NATIONAL CENTRE FOR INFORMATION AND DOCUMENTATION
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ADVANCES IN BULGARIAN SCIENCE
Annual ○○○○○ 2011 SOFIA
Advances in Bulgarian Science
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CONTENTS
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Prognostic Models for Assessment of Risk of Central Sleep Apnoea in Patients with Chronic Heart Failure. Effects from the Non-Invasive Ventilation 5 Psychophysical and Electrophysiological Approaches in Search of New Evidence for Separate S-OFF Pathway in Human Visual System. Investigations with Healthy Volunteers and Patients with Glaucoma 13 Concerning Genetic Variability and Usable Isozyme Markers for Characterization of A. Mellifera L. Populations and B. Mori L. Breeds in Bulgaria 20 Immunomodulatory Effects of Selected Lactobacillus Strains Against Inflammation in Human Intestines 28 Immobilization of Trichosporon Cutaneum R57 Cells onto SiO /HPC 2 Hybrid Materials and Removal of Mn 2+ Ions 33 Inverse Field Source Problems in Biomagnetics 38
An Integral Solution for Telemedicine and Hospital Information System 47
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The Genomic Research Center a Long Story Told in Short 54 Molecular Photonics Laboratory for Ultrafast Science and Technology at
Sofia University St. Kliment Ohridski 64
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Sensor Effector Boot Module for a New Technology Spinal Patients Rehabilitation 70 Libraries with PLC Programming Modules 76 Prototype GIS for Analysis and Protection of the Bulgarian Archaeological
Heritage ArchGIS 85
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BULGARIAN VIPs 92
AWARDS 97
ARTICLES 101
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EVENTS 105
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Advances in Bulgarian Science
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MAIN OBJECTIVES NACID is: Ø The leading institution in the national information infrastructure in Bulgaria in the sphere of education, science and innovations. Ø National information center for academic recognition and mobility (ENIC-NARIC center for Bulgaria). Ø Contact point to the Directive 2005/36/ÅC on the recognition of professional qualifications and delegated coordinator for Bulgaria in Internal Market Information (IMI) system. PRIMARY FIELDS OF ACTIVITIES: Ø Processing and dissemination of bibliographic and reference data and analytical information in support of the policy in the sphere of education, science, technology and innovations. Ø Building and maintaining specialized databases. Ø Maintaining national stock and DB of dissertations, deposited manuscripts and other scientific publications in Bulgaria. Ø Organizing application of ENIC-NARIC network decisions in the field of academic recognition. Ø Realizing information assistance in procedures for academic and professional recognition. Ø Performing activities resulting from the functions of ENIC-NARIC center. Ø Furnishing citizens and contact points in the rest of the member states with information in connection with recognition of professional qualifications and rights for practicing regulated professions in conformity with the Directive 2005/36/ÅC. Ø Performing functions of institutional contact point of the EUs Seventh Framework Programme. INFORMATION PRODUCTS AND SERVICES q NACID offers a wide range of information products: subject profiles, paper reviews, subject bibliographic and reference information. q NACID offers a great variety of information services through its own databases and resources, as well as through information brokerage to external databases. Online access is provided to NACIDs own databases grouped in two basic information blocks: Bulgarian Science Databases Science and Industry Databases Ø SIRENA, R&D reports and dissertations; Ø Partnership for Innovation and Development; Ø Scientific and Technical Publications in Bulgaria; Ø Knowledge for Innovations and Development . Ø Register of the Scientific Degrees and Titles; Information brokerage and servicing from external databases gives access to over 1200 databases of the leading information centers, including STN International Germany, DIALOG USA, EBSCO, etc. q Library Services Central Research and Technical Library (CRTL) with library information complex in pedagogics is one of the largest Bulgarian libraries and main supplier of information in the field of science, education, pedagogics, engineer- ing, technology and economy with more than 4 million registered items, including books, periodicals, dissertations, publications on CD ROM, DVD. It offers: Lending of library materials; Electronic Document Delivery; Online access to the library catalogues since 1980; Interlibrary loan. Searching in electronic catalogues and databases; INTERNATIONAL ACTIVITY Represents the Republic of Bulgaria in international organizations on the subject of its activities. Joint actions and projects with related national information and documentation centers in the EU.
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National Scientific Programmes with European Dimensions
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NATIONAL SCIENTIFIC PROGRAMMES WITH EUROPEAN DIMENSIONS
PROGNOSTIC MODELS FOR ASSESSMENT OF RISK OF CENTRAL SLEEP APNOEA IN PATIENTS WITH CHRONIC HEART FAILURE. EFFECTS FROM THE NON-INVASIVE VENTILATION
Kiril Terziyski1, Zdravko Z. Taralov1, Anna Hristova1, Ilcho Ilchev2, Okan Aliman2, Stefan Kostianev1 1Pathophysiology Dept., Medical University of Plovdiv 2Cardiology Dept., Medical University of Plovdiv 15-A, Vasil Aprilov Blvd., 4002 Plovdiv, Bulgaria
Abstract rate; chronotropic incompetence and heart rate Central sleep apnoea - Cheyne-Stokes respi- variability analysis. ration (CSA-CSR) is among the most important Basic parameters from the mentioned inves- factors responsible for the high morbidity and tigations and their derivatives will be juxtaposed preterm mortality of patients with chronic heart to chemodynamics condition (ejection fraction, failure (CHF). It is present in 30-50% of CHF pa- functional capacity); sleep architecture (non- tients. Despite its significant contribution to the REM and REM), apnoea-hypopnoea index and prognosis of CHF and its high frequency, few desaturation characteristics (amplitude, duration, large scale investigations on its prediction and specific characteristics), quality of life, etc. early diagnosis are present. The main reason for Grounded on the acquired results, an integrative its underdiagnosing is the fact that its diagnosis system (panel of parameters) for CSA risk pre- needs expensive and labour-consuming poly- diction in CHF will be proposed. This panel will be somnographic investigation. The aim of the proj- followed-up after therapy with positive airway ect is to further investigate some recently repor- pressure and oxygen therapy, if needed. The ex- ted parameters, informative of CSA risk in CHF, as pected results would contribute to the early di- well as to look for new parameters with predic- agnostics and purposeful treatment of CSA-CSR tive capabilities, based on the up-to-date knowl- in CHF. edge on CSA pathogenesis. The following parameters of the cardiorespi- INTRODUCTION ratory system will be investigated following scru- The problem with the early functional diag- tinized analysis of its functional profile: nostics of central sleep apnea (CSA) in patients Characteristics of tidal volume dynamics with chronic heart failure (CHF) has been a mat- (cyclic pattern), exhaled CO , ventilatory equiva- ter of extreme interest worldwide since the turn 2 lents at rest, during exercise and sleep. of the century. The bulk of scientific publications Gas exchange response - oxygen uptake, on this problem has been published in the last 5 exhaled CO2, ventilation and ventilatory equiva- years. A considerable part of the authors lents on different stages of exercise testing (on- pointed out the significance of the problem and set, anaerobic threshold, recovery). the necessity for additional research on the topic Changes in heart rate and the equilibrium and particularly on the construction of predictive sympathetic-parasympathetic regulation of heart models for CSA. Currently, leading teams have
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been involved with achieving this goal. No such Its clinical significance is determined by its fre- research has been done in Bulgaria so far, which quency, the lack of routine screening and/or eas- puts the scientific community in the country in ily available diagnostic method and the negative an unfavorable position as compared to its Eu- impact on morbidity and mortality in CHF pa- ropean and global counterparts. tients. Cheyne-Stokes respiration is a type of peri- Frequency of CSA-CSR odic breathing defined, according to the Ameri- Sleep disordered breathing in CHF is quite can Academy of Sleep Medicine criteria, as: at common: CSA-CSR is present in 30-50% of the least 3 consecutive cycles of crescendo-decre- patients, depending on the definition used, and scendo breathing with cycle length approxi- obstructive sleep apnea (OSA) - in 20-40%.2 CSA mately 60 seconds and at least one of the fol- frequency in CHF varies with CHF severity.3 lowing: 5 or more central apneas or hypopneas Significance of CSA-CSR for the develop- per hour of sleep or duration of the cycles at ment and prognosis of CHF least 10 minutes.1 Negative impact of CSA-CSR on CHF is sup- CSA-CSR is a sign of respiratory instability, ported by multiple studies showing increased particularly characteristic during sleep, when res- morbidity and mortality in CHF with CSA, com- piratory control is predominantly metabolic, pared to CHF without CSA, given that CHF is of based on a negative feedback mechanism, involv- comparable severity. 4,5,6 In a study on 353 pa- 2 ing PaO2 and PaCO2. tients the CHF+CSA showed significantly lower The pathophysiology of CSA-CSR in CHF is survival in comparison to CHF without sleep presented on Fig. 1. apnea and CSA/OSA without CHF (2.5 vs 4.5 vs
PCWP - pulmocapillary wedge pressure; SAA - sympathetic-adrenal activation; FRC - func- tional residual capacity
Fig. 1. Pathogenesis of CSA-CSR in CHF (based on Naughton2)
Significance of the central sleep apnea - 6.5 years).4 These results are in concordance with Cheyne-Stokes respiration in chronic heart the opinion of Somers et al stating that cardio- failure vascular diseases and CSA are potentiating each CSA-CSR is the most common type of CSA.2 other.7 Sleep apnea is a known risk factor for
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○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ arterial hypertension and increased morbidity, clinical profile of patients with CSA is scarce. and probably for increased cardiovascular dis- On the one hand, the characteristic loud snoring ease mortality. 8,9 This fact implicates its treat- is absent, and on the other - subjective daytime ment even in mild cases, aiming to avoid the de- sleepiness may be absent 13. velopment of the stated concomitant diseases.8,9 Against the backdrop of increased mortality Ancoli-Israel et al give the same recommendation, and morbidity rate in patients with pointing out elderly CHF patients as a risk group CHF+CA+CSR, it goes without saying that a for SA. 4 timely diagnostics and therapy of patients with Pathophysiological mechanisms linking CSA SDB is paramount. As of today, the golden with worse prognosis in CHF include: hypoxemia, standard for diagnosis of the above-mentioned sympathetic-adrenal activation and sleep frag- conditions is laboratory polysomnography, which mentation with frequent arousals.4 Sympathetic- can determine the various SDB14. It is, though a adrenal activation during sleep decreases very expensive, labor-consuming, highly special- cardiomyocyte life, has arhythmogenic effect ized analysis, and besides that the laboratories at and worsens ventricular energetics 6, while fre- hand cannot handle the existing flow of patients quent desaturations and multiple arousals im- with CHF at the registered frequency of 1-2% pose structural changes in the heart and left- 11,15. and right- ventricular hypertrophy.4 CSA-CSR Therefore, a number of scientists declare the causes impairment in CHF patients physical ca- need of a screening method for prediction of pacity, which by confining their physical activity CSA-CSR in CHF 4,11,14. This is further justified by leads to further progression of the main condi- the fact that these patients show excellent tion. 3,10,11 therapeutic results to different modes of non-in- Irrespective of the mentioned facts, some au- vasive ventilation with positive airway pressure 16. thors propose the hypothesis that CSA-CSR in Standard parameters used in the assessment CHF is not solely pathophysiological, but also a of CHF severity (NYHA functional class and ejec- compensatory-adaptive mechanism, bringing the tion fraction) and the quality of life in these following arguments: a) adaptation to the patients (assessed by Minnesota Living With present hypoxemia; b) increase in the pulmonary Heart Failure Questionnaire - MLHFQ), do not dif- oxygen storage by the gradual increase in the fer between CHF patients with or without SDB endexpiratory volume during the crescendo pe- 10,11,13,14,17 and are not usable for a screening riod of ventilation; c) under hypoxic conditions, method. muscle contractility is improved in the presence In the ideal case, a predictive system for CSA- of alkalosis; d) the increased non-obstructive CSB would be based on parameters from tests, ventilatory effort during CSA increases cardiac which are a part of the diagnostic approach to stroke volume; d) 20-30 sec ventilatory pauses CHF, minimally involving additional financial or during CSA are sufficient to prevent fatigue in human resource. Such tests are cardiopulmonary myopathic respiratory muscles 12. exercise testing (CPET), heart rate variability Diagnostic problems in CSA-CSR (HRV) analysis, modern laboratory parameters - Methodological problems are mainly in the brain natriuretic peptide (BNP) and high sensitiv- distinguishing between central and obstructive ity C-reactive protein (hsCRP). phenomena, based solely on the data from At the moment, parameters that had proved breathing and thoracic and abdominal channels, their distinguishing capability (concerning the especially concerning clasification of hypopneas. presence of CSA) are the cyclic pattern of The modern approach to a more precise diagno- breathing at rest 3,18 and in the first 4 minutes sis involves non-invasive measurement of the of veloergometry3 , the slope of the relationship respiratory effort by pulse transit time measure- between ventilation and carbon dioxide (VE/ 10,13 11,15 5,17 ment, instead of the gold standard - esophageal VCO2 slope) during CPET , HRV , BNP . catheter. Shortcomings of their single use to predict CSA- Unlike the case in obstructive sleep apnea, CSR are their insufficient specificity and sensitiv-
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ity, especially in mild cases 11,17. Contradictory re- There is, however, a part of the CSA-CSR pa- sults reported by Roche et al show extremely tients, who do not respond so well to therapy high sensitivity (92.9%), specificity (94.1%) and and that imposes the search for other alterna- predictive power (93.3%) of periodic breathing tives, for example, therapy with oxygen, with bi- pattern during the early part of CPET 3. However, level positive airway pressure (BiPAP), adaptive we think that presence or absence of variations servo-ventilation (ÀSV). Comparative character-
in ventilation, oxygen uptake and CO2 output, as- istics of the different therapeutic approaches are sessed visually is too subjective to serve as a presented in Table 1. widely used screening method. Adequate management of CHF is also an im- We think that present data for the effect of portant factor in treating CSA-CSR. It is related CSA-CSB on the above-mentioned diagnostic to improving circulatory time, as well as to con- parameters justify the search for a multicompo- troller gain and plant gain lowering, by means of nent screening system, based on these and other decreased stimulation of the irritative and parameters (e.g. chronotropic parameters from juxtacapillary receptors, improved perfusion of CPET, hsCRP). The complex approach probably the respiratory muscles and the lungs, resulting would increase specificity and sensitivity of the in better ventilation/perfusion proportion. screening. SCIENTIFIC TASKS Therapeutic approaches for CSA-CSR In the current project we plan to explore an Therapy with applying positive air pressure in unsolved medical problem, connected with the the airways (Continuous Positive Airway Pressure early diagnostics of central sleep apnea in - CPAP) is the most profoundly explored thera- chronic heart failure. In conjunction with the peutic strategy for CSA-CSR in patients with implementation of this fundamental idea the CHF.2 Mechanisms responsible for the effect of project pursues the following specific scientific that treatment are yet to be fully clarified, but objectives: the following are assumed: 1) preventing the Task 1. Defining the possibilities of various narrowing in the pharyngeal area during CSA, cardio-pulmonary and clinical and laboratory in- hence preventing hyperventilation, 2) improved dicators for prediction of central sleep apnea - oxygenation due to increased lung volume, 3) Cheyne-Stokes respiration in patients with improved cardiac function as a result of de- chronic heart failure. For this purpose the fol- creased pre-load and after-load (as a conse- lowing investigations will be carried out: quence of intrathoracic pressure elevation and 1. A panel of preliminary tests to determine transmural pressure reduction), 4) decreased study participation eligibility of each patient, ac- work of the respiratory muscles 2,19. In a large cording to the defined inclusion/exclusion crite- study involving 258 subjects (CANPAP), followed ria, shown on Fig. 2. up for a period of 2 years, the beneficial effect 2. Full-night polysomnogrpahy for diagnosing of the ÑÐÀÐ treatment has been proven, regard- the presence of CSA-CSR and dividing the pa- ing ejection fraction (EF), physical capacity, qual- tients into different groups. ity of life and sympatic activity. Mortality, on the 3. Cardio-pulmonary exercise testing (CPET) other hand, is comparable between the patients, with gas exchange analysis. Cycling patterns in receiving CPAP therapy and the control group 20. tidal volume (V ), ventilation (V ), oxygen uptake T E
A consecutive post-hoc analysis of the results of (VO2), carbon dioxide output (VCO2) at rest and that study show a significant decrease in the in the first 4 minutes of exercise will be assessed. mortality rate in the sub-group where treatment Analysis of the ventilatory efficiency in the has resulted in lowering the AHI<15 and con- course of CPET - ventilatory equivalents for O 2
cludes that the good response to the CPAP (VEVO2) and CO2 (VEVCO2) at peak exercise therapy (AHI<15) is an indication for treatment and AT, slope of the relationship VE-VCO2 of such patients 21. (VEVCO2 slope), oxygen uptake efficiency slope (OUES) will be performed. The chronotropic in- competence during exercise will be presented by
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calculation and analysis of heart rate response sleep apnea - Cheyne-Stokes respiration therapy (HRResp), heart rate reserve (HRReserve) and on the quality of life, physical ability and the chronotropic index (CRI). Exercise capacity will main functional parameters. We will determine also be assessed. the effect of the therapy on quality of life, psy- 4. Heart rate variability (HRV) analysis for chological status, exercise capacity and evaluation of the frequency characteristics of polysomnographic parameters (apneahypopnea the pulse at rest and during sleep, with emphasis index (AHI), sleep quality parameters, etc.). on very low frequency band (VLF-bands). STUDY DESIGN 5. Brain natriuretic peptide (BNP) measure- A schematic representation of the study de- ment. sign is presented on Fig. 2. Task 2. Integrating single predictors into a EXPECTED EFFECT AND RESULTS unified system for screening of patients with At the end of the study it is expected to be chronic heart failure for concomitant central created: sleep apnea - Cheyne-Stokes respiration. We System for risk stratification of CSA in pa- plan to create panels of parameters following tients with CHF, allowing for early detection with- hierarchical principle with respect to their appli- out the need for performing polysomnography cability to the level of healthcare: as a screening method. 1. Ambulatory level - specialist in cardiology. Algorithm for application of this system in 2. Ambulatory level - general practitioner. ambulatory practice and in specialized laborato- 3. Hospital level. ries. After that, we will perform prospective study The system will include parameters reflecting of the positive and negative predictive value, breathing, circulation and reactive homeostasis of specificity and sensitivity of the model, applying the organism with respect to rest exercise and it to patient groups with different functional sleep. class of cardiac dysfunction. The created system will be introduced in car- Task 3. Gauging the effect from central diologists practice in the hospital, the region and
Fig. 2. Design of the study
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○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ eventually the whole country. It is anticipated [10] Meguro K., Adachi H., Oshima S. et al. Exercise Tolerance, Exercise Hyperpnea and Central Chemosen- that this will lead to reduction of morbidity and sitivity to Carbon Dioxide in Sleep Apnea Syndrome in mortality in patient population with CHF. The re- Heart Failure Patients. Circ J 2005; 69: 695 -699. sults of the study will be disseminated in other [11] Vazir A., Dayer M., Hastings P.C. et al. Can centers in the country and abroad. heart rate variation rule out sleep disordered breath- ing in heart failure? Eur Respir J 2006; 27: 571-577. We expect the results will serve for establish- [12] Solin P., Kaye D.M., Little P.J. et al. Impact of ing an information database for studying the sleep apnea on sympathetic nervous system activity in pathogenesis and therapeutic options of CSA- heart failure. Chest. 2003 Apr; 123(4):1119-26. [13] Arzt M., Harth M., Luchner A. et al. Enhanced CHF. ventilatory response to exercise in patients with CONCLUSION chronic heart failure and central sleep apnea. Circu- CSA-CSR is associated with worsened prog- lation. 2003; 107(15):1998-2003. [14] Ferrier K., Campbell A., Yee B. et al. Sleep-Dis- nosis and quality of life in patients with CHF and ordered Breathing Occurs Frequently in Stable Outpa- therefore should be diagnosed and treated tients With Congestive Heart Failure. Chest 2005; properly. Practically applicable screening is not 128:2116-2122. available at the moment and ideally would be [15] Tateishi O., Shouda T., Honda Y. et al. Apnea- Related Heart Its Clinical Utility in Failure Outpatients based on routine cardiological investigations. The Rate Variability and Congestive Heart. A.N.E. 2002; project aims at creating such a multidimensional 7(2):127-132. screening system which is expected to have sig- [16] Leung R.S. & Bradley T.D. State of the art: sleep apnea and cardiovascular disease. Am J Respir nificant health and economic impact. Crit Care Med. 2001; 164:2147-2165. References [17] Christ M., Sharkova Y., Fenske H. et al. Brain [1] Iber C., Ancoli-Israel S., Chesson A. et al. for natriuretic peptide for prediction of Cheyne-Stokes the American Academy of Sleep Medicine. The AASM respiration in heart failure patients. International Jour- Manual for the Scoring of Sleep and Associated nal of Cardiology 2007; 116:62-69. Events: Rules, Terminology and Technical Specifica- [18] Leite J.J., Mansur A.J., de Freitas H.F. et al. Peri- tions. Westchester: American Academy of Sleep Medi- odic breathing during incremental exercise predicts cine, 2007. mortality in patients with chronic heart failure evalu- [2] Naughton M.T. & Lorenzi-Filho G. Sleep in ated for cardiac transplantation. J Am Coll Cardiol Heart Failure. Progress in Cardiovascular Diseases 2003; 41:2175-81. 2009; 51 (4): 339-349. [19] Badr S. Central sleep apnea in patients with [3] Roche F., Maudoux D., Jamon Y. et al. Moni- congestive heart failure. Heart Fail Rev 2008; toring of ventilation during the early part of cardiop- 14(3):135-41. ulmonary exercise testing: The first step to detect [20] Bradley T.D., Logan A.G., Kimoff R.J. et al.; central sleep apnoea in chronic heart failure. Sleep CANPAP Investigators. Continuous positive airway Medicine 2008; 9: 411-417. pressure for central sleep apnea and heart failure. N [4] Ancoli-Israel S., DuHamel E.R., Stepnowsky C. Engl J Med 2005; 353(19):2025-33. et al. The Relationship between Congestive Heart Fail- [21] Arzt M., Floras J.S., Logan A.G. et al.; CANPAP ure, Sleep Apnea, and Mortality in Older Men. Chest Investigators. Suppression of central sleep apnea by 2003; 124:1400-1405. continuous positive airway pressure and transplant- [5] Carmona-Bernal C., Quintana-Gallego E., Villa- free survival in heart failure: a post hoc analysis of the Gil M. et al. Brain Natriuretic Peptide in Patients with Canadian Continuous Positive Airway Pressure for Congestive Heart Failure and Central Sleep Apnea. Patients with Central Sleep Apnea and Heart Failure Chest 2005; 127:1667-1673. Trial (CANPAP). Circulation 2007; 115(25):3173-80. [6] Mansfield D., Kaye D.M., La Rocca H.B. et al. [22] Arzt M., Schulz M., Schroll S. et al. Time course Raised Sympathetic Nerve Activity in Heart Failure and of continuous positive airway pressure effects on Central Sleep Apnea Is Due to Heart Failure Severity. central sleep apnoea in patients with chronic heart Circulation 2003; 107:1396-1400. failure. J. Sleep Res. 2009; 18:20-25. [7] Somers V.K. To sleep, perchance to breathe: [23] Seino Y., Imai H., Nakamoto T. et al.; CHF-HOT. implications for the failing heart. Am J. Respir Crit Clinical efficacy and cost-benefit analysis of noctur- Care Med 1999; 160:1077-1078 nal home oxygen therapy in patients with central [8] Nieto F.J., Young T., Lind B. et al. Association of sleep apnea caused by chronic heart failure. Circ J. sleep-disordered breathing, sleep apnea, and hyper- 2007 Nov; 71(11):1738-43. tension in a large community-based study. JAMA [24] Shigemitsu M., Nishio K., Kusuyama T. et al. 2000; 283:1829-1836. Nocturnal oxygen therapy prevents progress of con- [9] Peppard P., Young T., Palta M. et al. Prospec- gestive heart failure with central sleep apnea. Int J tive study of the association between sleep-disor- Cardiol. 2007 Feb 14; 115(3):354-60. dered breathing and hypertension. N Engl J Med [25] Toyama T., Seki R., Kasama S. et al. Effective- 2000; 342:1378-1384 ness of Nocturnal Home Oxygen Therapy to Improve
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Exercise Capacity, Cardiac Function and Cardiac Sym- øàíå (ÖÑÀ-×ÑÄ). Òÿ ñå ñðåùà ïðè 30-50% îò pathetic Nerve Activity in Patients With Chronic Heart ïàöèåíòèòå ñ ÕÑÍ. Âúïðåêè çíà÷åíèåòî é çà Failure and Central Sleep Apnea. Circ J 2009; 73: 299 ïðîãíîçàòà è âèñîêàòà é ÷åñòîòà, ìàëêî ñà ìà- - 304. ùàáíèòå ïðîó÷âàíèÿ, ïîñâåòåíè íà íåéíîòî ïðå- [26] Teschler H., Dohring J., Wang Y.M. et al. Adap- äâèæäàíå è ðàííî äèàãíîñòèöèðàíå. Îñíîâíàòà tive pressure support servo-ventilation: a novel treat- ïðè÷èíà çà íåäîñòàòú÷íîòî é äèàãíîñòèöèðàíå å, ÷å ment for Cheyne-Stokes respiration in heart failure. äèàãíîñòèêàòà é íàëàãà ñêúïî è òðóäîåìêî Am J Respir Crit Care Med 2001; 164(4):614-9. ïîëèñîìíîãðàôñêî èçñëåäâàíå. Öåëòà íà ïðîåêòà å [27] Pepperell J.C.T., Maskell N.A., Jones D.R. et al. âúç îñíîâà íà ñúâðåìåííèòå äàííè çà ïàòîãåíåçàòà A randomised controlled trial of adaptative ventila- íà ÖÑÀ â õîäà íà ÑÍ äà ñå ïðîó÷àò íÿêîè tion for Cheyne-Stokes breathing in heart failure. Am íàáåëÿçàíè âå÷å â ëèòåðàòóðàòà ïîêàçàòåëè, êàêòî J Respir Crit Care Med 2003; 168:1109-1114. è äà ñå ïîòúðñÿò íîâè ïàðàìåòðè, êîèòî íîñÿò [28] Philippe C., Stoica-Herman M., Drouot X. et al. èíôîðìàöèÿ çà ðèñêà îò ÖÑÀ ïðè ÕÑÍ. Compliance with and effectiveness of adaptive Îò ñòðàíà íà êàðäèîðåñïèðàòîðíàòà ñèñòåìà servoventilation versus continuous positive airway ñëåä ùàòåëåí àíàëèç íà íåéíèÿ ôóíêöèîíàëåí pressure in the treatment of Cheyne-Stokes respira- ïðîôèë, ùå ñå èçñëåäâàò: tion in heart failure over a six month period. Heart Îñîáåíîñòè â äèíàìèêàòà (öèêëè÷åí ïàòåðí) 2006; 92:337-42. íà äèõàòåëíèÿ îáåì, èçäèøàíèÿ CO2, âåíòèëà- [29] Szollosi I., Jones M., Morrell M.J. et al. Effect òîðíèòå åêâèâàëåíòè ïðè ïîêîé, íàòîâàðâàíå è ñúí. of CO2 inhalation on central sleep apnea and arous- Îòãîâîðúò íà ãàçîâàòà îáìÿíà - êèñëîðîäíà als from sleep. Respiration. 2004; 71(5):493-8. êîíñóìàöèÿ, èçäèøàí CO , âåíòèëàöèÿ è âåíòè- [30] Javaheri S. Acetazolamide Improves Central 2 Sleep Apnea in Heart Failure. Am J Respir Crit Care ëàòîðíè åêâèâàëåíòè íà ðàçëè÷íè åòàïè îò ôèçè- Med 2006; 173:234-237. ÷åñêîòî íàòîâàðâàíå (íà÷àëî, àíàåðîáåí ïðàã, âúçñòàíîâÿâàíå). ÏÐÎÃÍÎÑÒÈ×ÍÈ ÌÎÄÅËÈ ÇÀ ÎÖÅÍÊÀ ÍÀ Ïðîìåíè â êàðäèîôðåêâåíöèÿòà è ñúñòîÿíè- ÐÈÑÊÀ ÎÒ ÖÅÍÒÐÀËÍÀ ÑÚÍÍÀ ÀÏÍÅß ÏÐÈ åòî íà ñèìïàòèêóñîâî-ïàðàñèìïàòèêóñîâî ðåãóëè- ÁÎËÍÈ Ñ ÕÐÎÍÈ×ÍÀ ÑÚÐÄÅ×ÍÀ ðàíå íà ñúðäå÷íàòà ÷åñòîòà; õðîíîòðîïíàòà èíêîì- ÍÅÄÎÑÒÀÒÚ×ÍÎÑÒ. ÅÔÅÊÒÈ ÎÒ ïåòåíòíîñò è ÷åñòîòåí àíàëèç íà ïóëñîâàòà ÍÅÈÍÂÀÇÈÂÍÀÒÀ ÂÅÍÒÈËÀÖÈß âàðèàáèëíîñò. Îñíîâíèòå ïîêàçàòåëè îò òåçè èçñëåäâàíèÿ è Êèðèë Òåðçèéñêè1, Çäðàâêî Ç Òàðúëîâ1, òåõíèòå ïðîèçâîäíè ùå ñå ñúïîñòàâÿò ñúñ ñúñòîÿ- Àííà Õðèñòîâà1, Èë÷î Èë÷åâ2, íèåòî íà õåìîäèíàìèêàòà (ôðàêöèÿ íà èçòëàñêâà- Îêàí Àëèìàí2, Ñòåôàí Êîñòÿíåâ1 íå, ôóíêöèîíàëåí êàïàöèòåò); àðõèòåêòîíèêàòà íà ñúíÿ (íîí-ÐÅÌ è ÐÅÌ ôàçè), àïíåè÷íî-õèïîïíåè÷- 1Êàòåäðà Ïàòîôèçèîëîãèÿ, Ìåäèöèíñêè íèÿ èíäåêñ è õàðàêòåðèñòèêà íà äåñàòóðàöèèòå óíèâåðñèòåò - Ïëîâäèâ (òåæåñò, ïðîäúëæèòåëíîñò, ñïåöèôè÷íè îñîáåíîñ- 2Êàòåäðà Êàðäèîëîãèÿ, Ìåäèöèíñêè óíèâåðñèòåò - òè), êà÷åñòâîòî íà æèâîò íà ïàöèåíòèòå è äð. Âúç Ïëîâäèâ îñíîâà íà ïîëó÷åíèòå ðåçóëòàòè ùå ñå ïðåäëîæè áóë. Âàñèë Àïðèëîâ 15-À, 4002 Ïëîâäèâ èíòåãðèðàí ïàíåë (ñèñòåìà) îò ïîêàçàòåëè çà îò÷èòàíå íà ðèñêà îò ÖÑÀ ïðè ÕÑÍ. Òîé ùå áúäå Ðåçþìå ïðîñëåäåí è ñëåä ëå÷åíèå íà áîëíèòå ñ íåèíâàçèâ- Åäèí îò âàæíèòå ôàêòîðè çà âèñîêàòà ìîðáèä- íà âåíòèëàöèÿ è åâåíòóàëíî ñ êèñëîðîäîòåðàïèÿ. íîñò è ïðåæäåâðåìåííàòà ñìúðòíîñò ïðè áîëíèòå Ïîëó÷åíèòå ðåçóëòàòè îò ïðîó÷âàíåòî ùå ïîçâîëÿò ñ õðîíè÷íà ñúðäå÷íà íåäîñòàòú÷íîñò (ÕÑÍ) å äà ñå íàïðàâè êðà÷êà â ðàííàòà äèàãíîñòèêà è öåíòðàëíàòà ñúííà àïíåÿ-×åéí-Ñòîóêñîâîòî äè- öåëåíàñî÷åíî ëå÷åíèå íà ÖÑÀ-×ÑÄ ïðè ÕÑÍ.
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National Scientific Programmes with European Dimensions
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PSYCHOPHYSICAL AND ELECTROPHYSIOLOGICAL APPROACHES IN SEARCH OF NEW EVIDENCE FOR SEPARATE S-OFF PATHWAY IN HUMAN VISUAL SYSTEM. INVESTIGATIONS WITH HEALTHY VOLUNTEERS AND PATIENTS WITH GLAUCOMA
Kalina Racheva, Milena Mihaylova, Stilian Georgiev, Christina Christova, Ivan Hristov, Tsvetalin Totev, Dimitar Mitov Institute of Neurobiology, Bulgarian Academy of Sciences Acad. G. Bonchev Str., Bl. 23, 1113 Sofia, Bulgaria
Abstract S-ON and S-OFF channels received by Vassilev et A basic principle of the visual system organi- al. (2003). The data from this experiment, con- zation is information transmission about light ducted with both healthy volunteers and pa- changes along two different pathways - ON è tients suffering from glaucoma, will provide new OFF, transmitting signals for luminance increase opportunities to develop faster and more con- (increment) and luminance decrease (decre- venient clinical test for early diagnosis of glau- ment) respectively from the separate areas of coma, based on VEP changes in perception of S the retina. Daylight vision in primates (including cones selective stimuli. Creation of such a test is humans) is subserved by three types of cones, of exceptional importance, because standard di- short wavelength (S-cones), middle wavelength agnostic approaches are not sensitive in the ini- (M-cones) and long wavelength (L-cones). The tial stages of the disease, while early detection of segregation of the information from the M and glaucoma is essential in fighting its progression. L cones along ON and OFF pathways takes place as early as the cone-bipolar cell synapse. The INTRODUCTION existence of ON channel of short wavelength Vision is the main source of information sensitivity photoreceptors has also been proved, about the surrounding world for humans and while the existence of S-OFF channel is a matter higher primates. A basic principle of the visual of debate. The present project proposes to ex- system organization is information transmission tend a fundamental research, undertaken in the along two different pathway types - ON path- Processing of visual information laboratory, in way, transmitting signals for luminance increase search of new evidence about the existence of (increment) and OFF pathway, transmitting sig- S-OFF pathway. An interdisciplinary approach will nal for luminance decrease (decrement) respec- be applied combining psychophysical and tively from separate retinal areas. Daylight vision electrophysiological methods in conditions of se- in primates (including humans) is subserved by lective stimulation of shortwave sensitive cones. three types of photoreceptors, short wavelength Visual evoked potentials (VEP) will be recorded, (S), middle wavelength (M) and long wavelength using large size stimuli, covering the entire moni- (L) sensitive cones. The existence of S-ON bipo- tor screen, and a long stimulus duration, which lar cells (Mariani, 1984; Kouyama & Marshak, will allow separating onset from offset re- 1992; 1997) and ganglion cells (Dacey & Lee, sponses. The results obtained might be inter- 1994; Dacey, 1993) is well proved. However, the preted as electrophysiological evidence about existence of S-OFF bipolar and ganglion cells is the existence of separate S-OFF pathway. VEPs a matter of debates. According to most to blue brightness increment and decrement electrophysiological findings from the lateral stimuli with size consistent with the area of com- geniculate nucleus (LGN), S-OFF cells are en- plete spatial summation (Riccos area) will also countered much more rarely than S-ON cells (re- be registered. The results obtained will be an cently Smajda, Buzas, FitzGibbon, & Martin, 2006). electrophysiological correlate of psychophysical This asymmetry disappears in primary visual cor- data about differences in spatial summation in tex (Mullen, Dumoulin & Hess, 2008), a finding
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that has no explanation yet. Jankov (1988) recorded visually evoked cor- Contrary to the subcortical asymmetry of S- tical potentials (VECPs) to stimulus increments ON and S-OFF pathways, a number of psycho- applying Stiles two-color method of selective physical studies has shown that the visual sys- stimulation of the S and L-cones. VEPs to a red tem is equally sensitive to luminance increment light were of large amplitude and were clearly and decrement signals that stimulate selectively visible at both onset and offset of the stimulus. short wavelength sensitive cones. Offset components to violet light were recorded In the Institute of Neurobiology, BAS, series of rarely (with 2 of 14 subjects) and were always experiments were conducted in order to prove of small amplitude. the existence of separate S-OFF pathway Study of S-cones and their pathways is of (Vassilev, Zlatkova, Manahilov, Krumov, & great interest because short wavelength system Schaumberger, 2000; Vassilev, Mihaylova, Racheva, is morphologically, genetically, physiologically and Zlatkova, Anderson, 2003; Racheva, Vassilev, 2008, psychophysiologically distinct from the other 2009; Racheva, 2011). Spatial summation for S- two systems and it is the most sensitive to reti- cone ON and OFF signals as a function of retinal nal diseases. Several studies have demonstrated eccentricity was studied and a psychophysical that glaucoma is associated with disturbances in correlate of unequal density of S-ON and S-OFF blue color perception (Johnson, Adams, Casson, cells was found. For the first time data about Brandt, 1993; Horn, Jonas, Budde, Junemann, spatial summation of S-OFF stimuli at different Mardin, Korth, 2002; Aldebasi, Drasdo, Morgan, retinal eccentricity were shown. It was found North, 2003; Drance, Lakowski, Schulzer, Douglas, that spatial summation varied for increments 1981). and decrements along the retinal eccentricity in Primary open-angle glaucoma is a common a different way, suggesting that the underlying disease and is one of the most frequent causes mechanisms processing the S-ON and the S-OFF of blindness. Early diagnosis is crucial for com- stimuli are different. In subsequent experiments bating the disease progression. Routine screening reaction time (RT) to near-threshold stimuli was tests are able to detect only a part of the glau- measured. In order to avoid spatial contrast be- coma cases. The standard diagnosis tests like tween the test stimulus and the background subjective perimetry depend to a great extent they were of the same spatial size and over- on the patients cooperation. Moreover, these lapped each other. The results obtained showed tests are not sensitive in the early glaucoma that human visual system is more sensitive to stage (Vistamehr, Shelsta, Palmisano, et al., 2006; stimulus onset than to stimulus offset when Cockburn, 2000). In last years objective tech- duration of S-cone selective stimuli was shorter, niques for eye diagnosis have been developed probably as a result of the slow adaptation of (Horn et al., 2002; Crognale, 2002; Rodarte, Hood, the short-wavelength-sensitive system. Indeed, Yang et al., 2006; Tobimatsu, Celesia, 2006). One the response to the stimulus offset appeared of these approaches is the objective assessment when stimulus duration became longer. All these of visual functions through analysis of data might be interpreted as a result of the electrophysiological responses from the visual longer time constant of the blue cones system cortex, using the method of VEPs (Tobimatsu, (Hughes & DeMarco, 2003), rather than as a sus- Celesia, 2006, Aldebasi et al., 2006, Crognale, 2002, tained response of a system sensitive to the Sartucci, Murri, Orsini, Porciatti, 2001). stimulus presence. The response of the S-ON and Resent research (Bessler, Klee, Kellner & S-OFF cells in LGN is more probably sustained, Haueisen, 2010) analyzes VEPs recorded under while the response of neurons in magnocellular selective stimulation of the separate color chan- (M) geniculate layers is more probably transient nels using the silent substitution method. The (Reid & Shapley, 2002). If the type of the re- results obtained show impressive differences in sponse correlates with the time course of adap- the VEPs to a blue channel stimulation in pa- tation, than the adaptation of cells transmitting tients with glaucoma and age-matched healthy S-cone signals should be the slowest. subjects. However, the isoluminant stimulation
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National Scientific Programmes with European Dimensions
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Advances in Bulgarian Science
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isolumination. The present project proposes to 2008). Similar apparatus will be constructed for optimize the electrophysiological method for the purposes of the present experiments. The early diagnosis of glaucoma. VEP will be regis- source of the blue light will be a monitor and the tered using a small stimulus size which will ac- stimuli will be generated on its screen by a Visual curately reflect the specific retinal changes with Stimulus Generator VSG 2/3 of Cambridge Re- increasing eccentricity. Furthermore, instead of search Systems and Psycho program of the using the silent substitution method the short same company. The bright yellow component in wave system will be isolated by the method of the experiments will be provided by slide projec- Styles (Wyszecki & Stiles, 1982), which has proven tor. Both sources will be superimposed at the eye its efficiency in various studies. by a neutral semitransparent mirror. The flow of METHODS the slide projector will pass through a yellow Method of Styles. In the experiments pro- glass filter, practically not transparent in the posed a two-color threshold method of Stiles short-wave area of the visual spectrum. will be employed for selective stimulation of the The yellow background intensity in the ex- S-cones (Wyszecki & Stiles, 1982), i.e. the blue test periments proposed will be 360 cd/m2. Our pre- stimuli will be presented after adaptation to a vious experiments have shown that the thresh- bright yellow background. This method was old/background intensity curve reached a pla- modified previously by Vassilev et al. (2000) by teau above 300 cd/m2, thus becoming independ- adding a dim blue light to the background, thus ent of the background level (Vassilev et al., allowing presentation of both increments and 2003) (Fig. 2). This indicates that above 300 cd/ decrements. m2 saturation level of the M and L cones was
Fig. 1. Apparatus for S cones selective stimulation (from Vassilev et al., 2000)
Fig. 1 schematically describes the apparatus reached and test stimuli were detected by S- used in previous laboratory experiments cones only. M and L cones are sensitive to the (Vassilev et al. 2000, 2003, Racheva & Vassilev, yellow background and therefore the threshold
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National Scientific Programmes with European Dimensions
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ no longer depends on background intensity. analyzed by averaging the spectral power of sin- Therefore, 360 cd/m2 yellow background inten- gle-trial EEGs. Next scheme will show event-re- sity is bright enough to suppress M and L cone lated synchronization/ desynchronization. For sensitivities. extraction of time-locked activity associated with
Fig. 2. Increment threshold for a blue test stimulus as a function of the luminance of the yellow background component. The luminance of the blue background was fixed at 3 cd/m2. Data obtained at 0 and 15 deg from fovea. The test stimulus diameter was 0.5 deg in the fovea and 2 deg at the periphery. Vertical bars - the 95% confidence intervals. Arrows - the background inten- sity at which spatial summation was studied. Subject: KR. (Adapted from Vassilev et al., 2003)
Experimental procedures and conditions will stimulus presentation, each synchronized with be similar to those used in Vassilev et al. (2000, stimulus trial of EEG record will be filtered in 2003) and Racheva & Vassilev (2008). All ex- appropriate frequency range: delta, theta, alpha, periments will be performed in a dark room. and beta. Then the absolute value of the filtered Viewing will be monocular, with the right eye, activity before and after visual stimulus onset through the natural pupil. Observers will be will be averaged for all stimuli. The obtained adapted for 10 min in darkness and then to the curve can be interpreted in terms of event-re- background for 2 min. Blue luminance increments lated synchronization and desynchronization in and decrements will be used as test stimuli and selected frequency range. The last approach their spatial and temporal parameters will be dif- concerns the change of fractal dimension of EEG ferent and will vary depending on the experi- due to visual stimuli. Each synchronized with ment purpose. visual stimulus trial of EEG record will be divided Electroencephalograms (EEGs) will be re- into overlapping windows and for each window corded using a dense array of scalp electrodes the fractal dimension (FD) will be calculated by around the striate cortex. The EEG recording ep- Higuchi method. FD is parameter related to cou- och will depend on the stimulus duration and pling and decoupling of neuronal oscillators will start 500 ms prior the stimulus onset. An (Basar, 1983) due to sensory-motor and cognitive age-matched healthy subject group of approxi- information processing. Thus, for each stimulus mately the same number of participants will be new FD time-series will be calculated. The time- employed to compare their experimental data series will be averaged similar to the ERPs. with the group of patients with glaucoma. EXPECTED RESULTS AND IMPACT Several schemes will be used to test the cor- We expect that the results obtained from the relation between behavioral performance and proposed experiments would be of both theo- cortical activity. First, event-related potentials retical and practical importance. It is expected to (ERPs) will be extracted from the non-event-re- receive direct electrophysiological evidence about lated noise by averaging single-trial EEGs which the existence of separate S-OFF pathway and are time-locked to the event. Second, non-phase- thus to confirm our recent psychophysical data. locked (induced) oscillatory activity will be The new data would contribute to resolving the
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Advances in Bulgarian Science
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discussion whether the blue-yellow channel way and L- and M-cone Pathway in Glaucoma. Inves- tigative Ophthalmology & Visual Science, 51, 319-326. processing signals from S-cones is composed of [4] Brindley G. S. (1970). Physiology of the retina two separate neural mechanisms (S-ON and S- and visual pathways, 241-246. Second Edition. London: OFF pathways). The possible existence of sepa- Edward Arnolds. rate S-ON and S-OFF pathways in the human [5] Calkins, D. J., Tsukamoto, Y. & Sterling, P. (1998). Microstructure and mosaic of a blue-yellow visual system would also be important for un- Ganglion cell in the primate retina. The Journal of derstanding the principles of color vision, as well Neuroscience, 18(9), 3373 - 3385. as for optimization of current approaches in [6] Cockburn D. M. (2000). Diagnosis and man- agement of open angle glaucoma: suggested guide- medical practice and video technologies. lines for optometrists. Clin Exp Optom.;83:119-127. Moreover, early diagnosis of such socially im- [7] Crognale M. A. Development, maturation, and portant disease as glaucoma is essential in pre- aging of chromatic visual pathways: VEP results. J. Vis. 2002; 2:438-450. venting its progression. Because short wave [8] Crognale M. A., Switkes E., Rabin J., Schneck M. cones are less numerous, the blue system is most E., Haegerstromportnoy G., Adams A.J. Application of vulnerable for retinal diseases. In glaucoma early the spatiochromatic visual-evoked potential to detec- initial deficits in S-cones system stimulation could tion of congenital and acquired color-vision deficien- cies. J. Opt Soc Am A-Opt Image Sci Vis. 1993;10:1818- probably be manifested. Due to subcortical 1825. asymmetry in S-ON and S-OFF cells, it could be [9] Curcio, C. A., Allen, K. A., Sloan, K. R., Lerea, C. L., expected that glaucoma will affect first S-OFF Hurley, J. B., Klock, I. B. & Milam A. H. (1991). Distribu- tion and morphology of human cone photoreceptors pathway. As a result of the present project a stained with anti-blue opsin. The Journal of Compara- new faster non-invasive method for early glau- tive Neurology 312, 610 - 624. coma diagnosis, which can be used in clinical [10] Dacey, D. M., (1993). Morphology of a small field bistratified ganglion cell type in macaque and practice, is expected to be developed. The soft- human retina. Visual Neuroscience, 10, 1081 - 1098. ware developed during the project implementa- [11] Dacey, D. M. & Lee, B. B. (1994). The blue- tion will also enable to perform future research on opponent pathway in primate retina originates on the topic. from distinct bistratified ganglion cell type. Nature 367, 731 - 735. Individual participants in the present project [12] Drance S. M., Lakowski R., Schulzer M., Doug- will increase their scientific skills through mutual las G. R. (1981). Acquired color vision changes in glau- exchange of methodological approaches. During coma: use of 100-hue test and Pickford anomaloscope as predictors of glaucomatous field the project implementation workshops will take change. Arch Ophthalmol.; 99:829-831. place where project participants will report their [13] Georgiev S., Minchev Z., Christova Ch., activities. The results will be published in scientific Philipova D. EEG Fractal Dimension Measurement be- fore and after Human Auditory Stimulation. journals and will be reported on national and BIOAUTOMATION, 2009, 12, 70-81. international forums. The planned cooperation [14] Higuchi T. (1988). Approach to an Irregular with health care system units will enable future Time Series on the Basis of the Fractal Theory, Physica developments to be tested and used in medical D: Nonlinear Phenomena, 31, 277-283. [15] Horn F. K., Jonas J. B., Budde W. M., Junemann practice in a short time. A. M., Mardin C. Y., Korth M. (2002). Monitoring glau- Acknowledgment coma progression with visual evoked potentials of the This project is funded by the National Science blue-sensitive pathway. Invest Ophthalmol Vis Sci; 43:1828-1834. Fund at Ministry of Education, Youth and Science [16] Hughes, A., & DeMarco, P. J. (2003). Time with Contract DMU03-89/2011. course of adaptation to stimuli presented along car- dinal lines in color space. Journal of the Optical Soci- ety of America A, 20, 2216-2227. References [17] Jankov, E. (1988). New observations on the [1] Aldebasi Y. H., Drasdo N., Morgan J. E., North violet mechanism in man as revealed by the VECP. R. V. (2003). Cortical OFF-potentials from the S-cone Acta Physiologica and Pharmacologica Bulgarica, 14(1), pathway reveal neural damage in early glaucoma. Vi- 68-75. sion Res; 43:221-226. [18] Johnson C. A., Adams A. J., Casson E. J., Brandt [2] Basar E. (1983). Toward a Physical Approach J. D. (1993). Progression of early glaucomatous visual- to Integrative Physiology, American Journal of Physi- field loss as detected by blue-on-yellow and stand- ology, 245, R510-R533. ard white-on-white automated perimetry. Arch [3] Bessler P., Klee S., Kellner U., and Haueisen J. Ophthalmol.;111:651-656. (2010). Silent Substitution Stimulation of S-cone Path-
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[19] Kouyama, N. & Marshak, D. W. (1992). Bipo- ÏÑÈÕÎÔÈÇÈ×ÍÈ È ÅËÅÊÒÐÎÔÈÇÈÎËÎÃÈ×ÍÈ lar cells specific for blue cones in the macaque retina. ÏÎÄÕÎÄÈ Â ÒÚÐÑÅÍÅÒÎ ÍÀ ÍÎÂÈ The Journal of Neuroscience 12, 1233-1252. ÄÎÊÀÇÀÒÅËÑÒÂÀ ÇÀ ÑÚÙÅÑÒÂÓÂÀÍÅÒÎ ÍÀ [20] Kouyama, N. & Marshak, D. W. (1997). The ÎÒÄÅËÅÍ S-OFF ÏÚÒ Â ÇÐÈÒÅËÍÀÒÀ ÑÈÑÒÅÌÀ topographical relationship between two neuronal ÍÀ ×ÎÂÅÊ. ÈÇÑËÅÄÂÀÍÈß ÂÚÐÕÓ ÇÄÐÀÂÈ mosaics in the short wavelength-sensitive system of ÄÎÁÐÎÂÎËÖÈ È ÏÀÖÈÅÍÒÈ Ñ ÃËÀÓÊÎÌÀ the primate retina. Visual Neuroscience, 14, 159 - 167. [21] Mariani, A. P. (1984). Bipolar cells on monkey Êàëèíà Ðà÷åâà, Ìèëåíà Ìèõàéëîâà, Ñòèëèÿí retina selective for the cones likely to be blue-sensi- Ãåîðãèåâ, Õðèñòèíà Õðèñòîâà, Èâàí Õðèñòîâ, tive. Nature 308, 184-186. Öâåòàëèí Òîòåâ, Äèìèòúð Ìèòîâ [22] Mullen, K. T., Dumoulin, S. O., Hess, R. F. (2008). Èíñòèòóò ïî íåâðîáèîëîãèÿ, Áúëãàðñêà àêàäåìèÿ Color responses of the human lateral geniculate nu- íà íàóêèòå cleus: selective amplification of S-cone signals be- óë. Àêàä. Ã. Áîí÷åâ, áë. 23, 1113 Ñîôèÿ tween the lateral geniculate nucleon and primary visual cortex measured with high-field fMRI. Euro- Ðåçþìå pean Journal of Neuroscience, 28(9), 1911-1923. Îñíîâåí ïðèíöèï íà îðãàíèçàöèÿòà â çðèòåëíàòà [23] Racheva, K., Vassilev, À. (2008): Sensitivity to ñèñòåìà å ðàçäåëÿíåòî íà èíôîðìàöèÿòà çà ïðîìåíè stimulus onset and offset in the S-cone pathway. Vi- â ñâåòëèííàòà ñòèìóëàöèÿ ïî äâà îòäåëíè êàíàëà sion Research, 48, 1125-1136. ON è OFF, ïðîâåæäàùè ñèãíàëè ñúîòâåòíî çà óâåëè- ÷àâàíå (èíêðåìåíò) è íàìàëÿâàíå (äåêðåìåíò) íà [24] Racheva, K., Vassilev, À. (2009). Human S-cone îñâåòåíîñòòà îò îòäåëíèòå ó÷àñòúöè íà ðåòèíàòà. vision: effect of stimulus duration on the increment Äíåâíîòî çðåíèå ïðè ïðèìàòè (âêëþ÷èòåëíî è and decrement thresholds. Comptes rendus de ÷îâåê) ñå îñúùåñòâÿâà îò òðè âèäà ôîòîðåöåïòîðè lAcademie bulgare des Sciences, 62(1), 63-68. êúñîâúëíîâè (S), ñðåäíîâúëíîâè (M) è äúëãîâúëíî- [25] Reid, R. C. & Shapley R. M. (2002). Space and âè (L) êîëáè÷êè. Äîêàòî ðàçäåëÿíåòî íà èíôîðìàöè- time maps of cone photoreceptor signals in macaque ÿòà îò M è L êîëáè÷êèòå ïî ON è OFF ïúòèùà ñå lateral geniculate nucleus. The Journal of Neuro- èçâúðøâà îùå íà ðàííî íèâî ñèíàïñ Ì è L êîëáè÷êè science, 22(14), 6158 - 6175. áèïîëÿðíè êëåòêè, ïðè êúñíîâúëíîâèòå ôîòîðå- [26] Rodarte C., Hood D. C., Yang E. B., et al. The öåïòîðè å äîêàçàíî íàëè÷èåòî ñàìî íà ON êàíàë, à effects of glaucoma on the latency of the multifocal ñúùåñòâóâàíåòî íà OFF êàíàë å ñïîðíî.  íàñòîÿùèÿ visual evoked potential. Br J. Ophthalmol. 2006; ïðîåêò ñå ïðåäëàãà ïðîäúëæàâàíå íà ôóíäàìåíòàë- 90:1132-1136. íèòå èçñëåäâàíèÿ, çàïî÷íàòè â ëàáîðàòîðèÿ Ïðåðà- [27] Sartucci F., Murri L., Orsini C., Porciatti V. áîòêà íà çðèòåëíà èíôîðìàöèÿ, â òúðñåíå íà íîâè Equiluminant red-green and blue-yellow VEPs in mul- äîêàçàòåëñòâà çà íàëè÷èåòî íà S-OFF ïúò ïðè êúñî- tiple sclerosis. J. Clin Neurophysiol. 2001;18:583-591. âúëíîâàòà ñèñòåìà. Çà òàçè öåë ùå ñå èçïîëçâà [28] Stockman, A., Brainard, D. H. (2010). Color Vi- èíòåðäèñöèïëèíàðåí ïîäõîä, êîìáèíèðàù ïñèõîôè- sion Mechanisms. In Handbook of optics, Vol. III. Vi- çè÷íè è åëåêòðîôèçèîëîãè÷íè ìåòîäè, â óñëîâèÿòà sion and Vision Optics By Michael Bass, Casimer íà ñåëåêòèâíà ñòèìóëàöèÿ íà êúñîâúëíîâèòå êîëáè÷- DeCusatis, Jay M. Enoch, Vasudevan Lakshminarayanan, êè. Ùå ñå ðåãèñòðèðàò çðèòåëíî ïðåäèçâèêàíè ïîòåí- Guifang Li, Carolyn MacDonald, Eric Van Stryland, pp. öèàëè (ÇÏÏ) ïðè èçïîëçâàíåòî íà ãîëåìè ïî ðàçìåð 11.1-11.104. ñòèìóëè, çàåìàùè öåëèÿ åêðàí íà ìîíèòîðà. Ñòèìó- ëèòå ùå áúäàò ñ ãîëÿìà ïðîäúëæèòåëíîñò, êîåòî ùå [29] Szmajda B. A., Buzas, P., FitzGibbon, T. & Mar- ïîçâîëè îòäåëÿíåòî íà îòãîâîðèòå êúì âêëþ÷âàíå îò tin, P. R. (2006). Geniculocortical relay of blue-off sig- òåçè êúì èçêëþ÷âàíåòî íà ñòèìóëà. Ïîëó÷åíèòå ðå- nals in the primate visual system. PANS, 103(51), 19512- çóëòàòè ùå áúäàò ïðåêè åëåêòðîôèçèîëîãè÷íè äîêà- 19517. çàòåëñòâà çà ñúùåñòâóâàíåòî íà îòäåëåí S-OFF ïúò. [30] Tobimatsu S., Celesia G. G. Studies of human Âúâ âòîðèÿ åêñïåðèìåíò ùå áúäàò ðåãèñòðèðàíè ÇÏÏ visual pathophysiology with visual evoked potentials. ïðè ñèíè ÿðêîñòíè èíêðåìåíòíè è äåêðåìåíòíè Clin Neurophysiol. 2006; 117:1414-1433. ñòèìóëè ñ ðàçìåð, ñúîáðàçåí ñúñ çîíàòà íà ïúëíà [31] Vassilev, A. V., Zlatkova, M., Manahilov, V., ïðîñòðàíñòâåíà ñóìàöèÿ (çîíàòà íà Ðèêî). Ïîëó÷åíè- Krumov, K., & Schaumberger, M. (2000). Vision Re- òå ðåçóëòàòè ùå áúäàò åëåêòðîôèçèîëîãè÷åí êîðåëàò search, 40, 989 - 1000. íà ïñèõîôèçè÷íèòå äàííè çà ðàçëèêèòå â ïðîñòðàí- [32] Vassilev, À., Mihaylova, M., Racheva, K., Zlatkova, ñòâåíàòà ñóìàöèÿ â S-ON è S-OFF êàíàëèòå, ïîëó÷åíè M., Anderson, R. S. (2003): Spatial summation of S- îò Vassilev è ñúàâò. (2003). Äàííèòå îò òåçè åêñïåðè- cone ON and OFF signals: Effects of retinal eccentric- ìåíòè, ïðîâåäåíè êàêòî ñúñ çäðàâè äîáðîâîëöè, òàêà ity. Vision Research 43, 2875-2884. è ñ ïàöèåíòè, ñòðàäàùè îò ãëàóêîìà, ùå äàäàò íîâè [33] Vistamehr S., Shelsta H. N., Palmisano P. C., et âúçìîæíîñòè çà ðàçðàáîòâàíåòî íà ïî-áúðç è óäî- al. (2006). Glaucoma screening in a high-risk popula- áåí çà êëèíè÷íàòà ïðàêòèêà òåñò çà ðàííà äèàãíîñ- tion. J. Glaucoma; 15:534-540. òèêà íà ãëàóêîìà, îñíîâàí íà ïðîìåíèòå â ÇÏÏ ïðè [34] Wyszecki, G. & Stiles, W. S. (1982). Color sci- âúçïðèÿòèåòî íà ñåëåêòèâíè çà S-êîëáè÷êèòå ñòèìó- ence (2nd ed.). New York: John Wiley & Sons. ëè. Ñúçäàâàíåòî íà ïîäîáåí òåñò å îò èçêëþ÷èòåëíà [35] Ðà÷åâà Ê. (2011). Âðåìåâè è âàæíîñò ïîðàäè ôàêòà, ÷å ðàííàòà äèàãíîñòèêà íà ïðîñòðàíñòâåíè õàðàêòåðèñòèêè íà çðåíèåòî ïðè ãëàóêîìàòà å îò ðåøàâàùî çíà÷åíèå çà áîðáàòà ñ òî- âà çàáîëÿâàíå, à ñòàíäàðòíèòå äèàãíîñòè÷íè ïîäõî- èçáèðàòåëíà ñòèìóëàöèÿ íà êúñîâúëíîâèòå äè íå ñà ÷óâñòâèòåëíè â íà÷àëíèòå åòàïè íà çàáîëÿ- ôîòîðåöåïòîðè ó ÷îâåêà (äèñåðòàöèÿ). âàíåòî.
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Advances in Bulgarian Science
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CONCERNING GENETIC VARIABILITY AND USABLE ISOZYME MARKERS FOR CHARACTERIZATION OF A. MELLIFERA L. POPULATIONS AND B. MORI L. BREEDS IN BULGARIA
Teodora Staykova, Evgeniya Ivanova Plovdiv University Paisii Hilendarski, Department of Developmental Biology, Section of Genetics 24, Tzar Assen Str., 4000 Plovdiv, Bulgaria Phone: +359 261 549; Fax: +359 32 261 566 E-mail: [email protected]; [email protected]
Abstract importation of foreign bees. These activities have Genetic variability in different populations of had an impact on the genetic variability of the Bulgarian honey bee Apis mellifera from the all honey bees throughout the country. Although six main regions in the country have been stud- there are different studies concerning the degree ied using analysis of six enzymic systems corre- of genetic diversity of local Bulgarian honey bee, sponding to six loci (MDH 1, ME, EST 3, ALP, PGM they are mainly based on classical morphometry and HK). All of the studied loci were found to (Petrov 1990; 1995; 1996; 2000) and partially on be polymorphic. Three to six alleles were de- isoenzyme analysis (Ivanova et al., 2007; 2010a,b; tected for the different allozymic systems: three Ivanova and Bouga 2009). Even though some alleles - at MDH-1, ALP and HK loci; four alleles comparison between selectively reared in Bul- - at ME and PGM loci, and six - at EST-3 locus. garia lines have been done (Ivanova et al. 2010a; Genetic markers, usable for discrimination of Bul- 2011), genetic structures of honey bee po- garian honey bees were described in this study. pulations from all over the country have not A genetic analysis of three enzymic systems been compared yet and differencies between (PGM, MDH and HK) was conducted on 10 Bulgarian honey bees and other A. m. macedo- breeds of B. mori. Suitable isoenzyme markers nica populations are not enough clear. Hence, the were specified for evaluation of interbreed and present research focuses on: 1) detection of the intrabreed polymorphism and breed differentia- genetic variability among honey bee populations tion for this species. The phylogenetical relation- in Bulgaria and 2) search for genetic markers ships were studied. It was established that usable for discrimination of Bulgarian honey breeds E 27, Japanese 106 and Jena may be used bees. in future breeding programs as donor breeds as Utilization of isozyme markers provides the they are genetically distant from all others. opportunity to study genetic diversity of the mulberry silkworm (Chatterjee & Datta, 1992; INTRODUCTION Chatterjee et al., 1993; Eguchi, 1995), as well as to The most economically significant species of differentiate the various breeds (Abraham et al. insects Apis mellifera L. and Bombyx mori L. are 1992; Goldsmith 1995). Genetic resources of subject to purposeful selection activity and fun- more than 230 local and introduced breeds and damental scientific research in our country in the lines of Bombyx mori L., with various geographic recent years. origins have been maintained in Bulgaria. Their According to Ruttners morphometric analy- biodiversity has been studied mainly on the basis sis (1988), A. m. macedonica subspecies occur in of some main selection properties - qualitative Bulgaria but according to Petrov (1990), a native and quantitative. The isozyme polymorphism type, named as A. m. rodopica, exists in the with the breeds grown in Bulgaria is weakly country. Since 1930 honey bees in Bulgaria have studied. Their differentiation on the basis of iso- been studied for the selection purpose (Lazarov zyme markers has not been studied either. This 1935; 1936) and during the period 1971-1990 the research helped us to identify suitable isozyme local bee was threatened by queen breeding and markers to analyze the gene pool, genotypic
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Bulgarian populations. 2007, 2010a,b) and in Greece (Ivanova, 2010). Concerning ME locus, Dedej et al. (1996) re- Two more alleles of the same locus (PGM80 and ported no polymorphism in Greek populations, PGM125) were detected in the present study. but according to Bouga et al. (2005) this locus HK locus was found to be polymorphic with is polymorphic with two alleles in A. m. two alleles (HK100 and HK110) in A. m. mace- macedonica from Greece. In the present study, donica from Greece (Ivanova, 2010). In the four alleles of this locus were detected in Bul- present study a third allele - HK87 was found in garian populations. Bulgarian population and its frequency varied Three alleles of EST-3 locus were detected in between 0.007 and 0.027. A. m. macedonica from Greece (Bouga et al., All mentioned above private alleles in Bulgar- 2005; Ivanova, 2010), but in our research six ian populations (EST80, EST105, EST118, ALP90, PGM80, alleles were found. The alleles EST80, EST105 and PGM125 and HK87) could be used also for com- EST118 were detected only in Bulgarian honey bee parisons, discrimination and characterization of populations. Bulgarian honey bees. In this aspect, together Concerning the ALP polymorphism, two with the most frequent alleles (MDH100, ME100, alleles (ALP100 and ALP80) were detected in EST100, PGM100, HK100 and ALP80) they could be Greece (Bouga et al., 2005) and in Bulgaria useful as suitable genetic markers for selection (Ivanova et al., 2010a,b). In the present research, and conservation purposes. a third allele - ALP90 was observed and its fre- The mean number of alleles per locus varied quency varied between 0.0 and 0.136. from 2.5 (North West) to 3.7 (South East). The PGM locus was found to be polymorphic with estimated percentage of polymorphic loci two alleles (PGM100 and PGM114) in previously ranged from 50% (South West) to 83.3% studied populations from Bulgaria (Ivanova et al.,
Table 1. Number of samples studied (N) and data about the allele frequencies in the populations
Locus South West South Central South East North East North Central North West MDH-1 (N) 438 788 504 406 599 88 65 0.451 0.451 0.419 0.458 0.496 0.318 100 0.549 0.543 0.577 0.542 0.503 0.585 80 0 0.007 0.004 0 0.001 0.097 ME (N) 441 585 398 355 366 76 100 0.93 0.921 0.908 0.921 0.937 0.875 106 0.045 0.069 0.044 0.065 0.049 0.125 90 0.02 0.01 0.048 0.014 0.014 0 115 0.005 0 0 0 0 0 EST-3 (N) 442 758 480 372 527 69 80 0.008 0.036 0.011 0.02 0.013 0 100 0.974 0.923 0.953 0.952 0.956 0.949 88 0 0 0.005 0.007 0 0.029 118 0.016 0.022 0.004 0.013 0.011 0.022 94 0.002 0.015 0.014 0.008 0 0 105 0 0.005 0.013 0 0.019 0
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ALP (N) 386 618 385 318 550 68 80 0.517 0.513 0.403 0.539 0.585 0.537 100 0.47 0.47 0.461 0.418 0.408 0.463 90 0.013 0.017 0.136 0.042 0.006 0 PGM (N) 424 640 406 363 392 69 100 0.953 0.922 0.915 0.946 0.916 0.92 114 0.038 0.077 0.081 0.054 0.08 0.08 80 0 0 0.001 0 0 0 125 0.009 0.002 0.002 0 0.004 0 HK (N) 494 894 573 445 822 86 87 0.007 0.027 0.011 0.022 0.021 0.017 100 0.97 0.966 0.966 0.962 0.964 0.965 110 0.023 0.007 0.023 0.016 0.015 0.017
(South Central and North West). (Table 2). The The estimated mean FST value was 0.0068, observed and expected heterozygosity (Ho and which shows high level of genetic diversity within
He) ranged from 0.166 (North West) to 0.218 populations. The values of genetic distance (Nei, (North East) and from 0.224 (South West) to 1972) were calculated using the allele frequen- 0.264 (South East and North West), respectively cies (Table 1) and ranged from 0.001 to 0.008. (Table 2). There are significant deviations of In UPGMA dendrograms, North West and South genotype frequencies from Hardy-Weinberg ex- East populations were grouped separately. All pectations at most of the loci in most other populations were clustered together in populations (P ³ 0.01). Chi-Square (df: 1-6) tests two branches: first - North Central and North showed that the deviations were generally in East and second - South Central and South West favour of homozygotes. (Fig. 1).
Table 2. Observed and expected heterozygosity in the populations tested (Standard errors are included)
Population Mean Mean no. of Percent
sample size alleles per Polymorphic Ho He per locus locus loci(P=0.95) South West 437.5±14.2 3.2±0.3 50 0.21±0.094 0.224±0.089 South Central 713.8±48.7 3.3±0.3 83.3 0.203±0.079 0.254±0.082 South East 457.7±30.3 3.7±0.5 66.7 0.215±0.086 0.264±0.093 North East 376.5±17.9 3±0.4 66.7 0.218±0.089 0.241±0.087 North Central 542.7±67.2 3.2±0.2 66.7 0.18±0.07 0.237±0.083 North West 76±3.7 2.5±0.2 83.3 0.166±0.053 0.264±0.085
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Fig. 1. Relationships of honey bee populations studied as shown in UPGMA (Sneath and Sokal, 1973) dendrograms
Bombyx mori L. in the gene pool of the breeds Belopol 1/18, In two of the studied enzyme systems - Belopol 2/21 and Gergana 1 (Table 3). With
phosphoglucomutase and malate dehydroge- Kinshu, Jena and Å 27, allele Pgm À1 was missing. nase, we found out intrabreed and interbreed Pgm A was seen in the gene pool of all the 2 polymorphism (Table 3). We established inter- studied breeds, and with Gergana 2, M-6, Japa- breed polymorphism by means of hexokinase. nese 106 and Asahi this allele was fixed. Among Phosphoglucomutase from various organs of these breeds with established polymorphism, the
Table 3. Allele frequencies in breeds tested
Locus Breeds Pgm Mdh Hk A A A A A A A A 1 2 3 1 2 3 1 2 Belopol 1/18 0.038 0.438 0.525 0 1 0 0 1 Belopol 2/21 0.038 0.603 0.359 0 1 0 0 1 Gergana 1 0.265 0.500 0.235 0 1 0 0 1 Gergana 2 0 1 0 0 1 0 0 1 M-6 0 1 0 0 1 0 0 1 Japanese 106 0 1 0 0 1 0 1 0 Asahi 0 1 0 0.031 0.859 0.109 0 1 Kinshu 0 0.306 0.694 0.113 0.855 0.032 0 1 Jena 0 0.676 0.324 0 1 0 1 0 E 27 0 0.425 0.575 0 1 0 1 0
B. mori was determined by one locus for which highest frequency of allele Pgm À was estab- 1
a three-allelic polymorphism was described lished for Gergana 1, allele Pgm À2 - for Jena, and (Staykova, 2006; Staykova, 2008). With the allele Pgm À - for Kinshu. 3 breeds included in this study we established By means of electrophoresis in polyacryla- presence of all three alleles (Pgm A , A and A ) mide and cellulose acetate gel Marcato et al. 1 2 3
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(1990) found polymorphism by the loci coding (with Gergana 2, M-6 and Japanese 106) to 2.0 the phosphoglucose isomerase and mannose (with Kinshu). The degree of polymorphism (ac- phosphate isomerase, and lack of polymorphism cording to criteria 0.99) was highest for breed by the loci coding malate dehydrogenase, Kinshu (66.70%), and lowest - with Gergana 2, isocitrate dehydrogenase and other enzymes. M-6 and Japanese 106 (0%), where we observed Egorova and Nasirillaev (1993) reported the monomorphism in all studied loci. The estab- presence of MDH polymorphism at the lished heterozygosity (Ho) varied from 0.000 hemolymph of B. mori. For two of the breeds (with Gergana 2, M-6 and Japanese) to 0.151 studied by us we also found polymorphism on (with Kinshu). With all analyzed breeds with es- the malate dehydrogenase from the hemolymph tablished polymorphism the expected heterozy-
(Table 3). In the gene pool of the Japanese gosity (He) was higher than the one we ob- breeds Asahi and Kinshu we established the tained. The test for conformance to Hardy- presence of three alleles (Mdh A1, A2 and À3). In Weinberg equilibrium manifested significant dif- the gene pool of all other breeds, the Mdh A ferences between the obtained and expected 2 allele was fixed, which agrees with the estab- genotype frequencies, which were due to the es- lished by Marcato et al. (1990). tablished higher frequency of the homozygotes. Yanagawa (1978) studied the properties of The lower extent of established heterozygosity hexokinase from various tissues of the mulberry and the higher frequency of homozygote indi- silkworm (fat body, muscles, spermaries, midgut viduals were related to inbreeding effects. and Malpighian tubules) and established the tis- The average value of F (0.6131) calculated ST sue specificity in distribution of the multiple mo- on the basis of the established isozyme polymor- lecular forms. In the group of breeds of various phism showed that 61.31% of the genetic vari- origins studied in Bulgaria we established inter- ability was observed between different breeds, breed polymorphism by the hexokinase of the silk which also corresponded to the degree of inter- glands and the lack of intrabreed polymorphism breed differentiation, whereas 38.69% of the (Table 3). In the gene pool of Japanese 106, Jena genetic variability was intrabreed. The highest and E 27 we ascertained the presence of the Hê extent of interbreed variability was accounted by
A1 allele, whereas in the gene pool of all other hexokinase (1.000). breeds we ascertained the Hê A allele. On the grounds of the allele frequencies, the 2 The average number of alleles per locus cal- genetic distance by Nei (Nei, 1972) was also cal- culated by BIOSYS-1 (Table 4) varies from 1.0 culated, which was the base for constructing a
Table 4. Mean number of alleles per locus, proportion of polymorphic loci, observed (H ) and expected heterozygosity (H ) o e Percent Mean Mean no. of Polymorphi
Breeds sample size alleles per c loci Ho He per locus locus (P=0.99) Belopol 1/18 40.0 1.7±0.7 33.3 0.050 0.179 Belopol 2/21 39.0 1.7±0.7 33.3 0.060 0.171 Gergana 1 34.0 1.7±0.7 33.3 0.088 0.211 Gergana 2 30.0 1.0±0.0 0.0 0 0 M-6 30.0 1.0±0.0 0.0 0 0 Japanese 106 36.0 1.0±0.0 0.0 0 0 Asahi 32.0 1.7±0.7 33.3 0.052 0.084 Kinshu 31.0 2.0±0.6 66.7 0.151 0.231 Jena 34.0 1.3±0.3 33.3 0.078 0.148 E 27 40.0 1.3±0.3 33.3 0.050 0.165
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UPGMA dendrogram (Fig.2). It shows that ing the intrabreed polymorphism and establishing within the group of studied breeds two main the degree of intrabreed genetic variability. clusters were formed. In the first cluster the • The established isozyme markers could be breeds E 27, Japanese 106 and Jena were distrib- used in the future breeding and selection work uted, and in the other - all others. on creating initial populations and performing
Fig. 2. Relationships of studied breeds as shown in UPGMA (Sneath and Sokal, 1973) dendrograms
CONCLUSIONS interbreed hybridization. Concerning Apis mellifera, the obtained re- • Breeds E 27, Japanese 106 and Jena could sults in the present study give us the grounds to be included in selection programs as donor draw the flowing deductions: breeds, as they are genetically distant from all • The allozyme systems studied in this inves- others. tigation are useful for characterization of ge- Acknowledgments netic variability in honey bee populations and This work has been financed by Scientific Re- show a high level of genetic diversity within Bul- searches Fund at the Ministry of Education, garian populations. Youth and Science - contract DO 02-63/ • The indicated in this study allozyme genetic 11.12.2008. markers are appropriate for comparisons, dis- References crimination and characterization of Bulgarian honey bees and would be useful for selection [1] Abraham E.G., Nagaraju J., Datta R.K. 1992. Bio- chemical studies of amylases in the silkworm, Bombyx and conservation purposes. mori L.: Comparative analysis in the diapausing and The accomplished study for establishing suit- nondiapausing strains. Insect Biochemistry and Mo- able isozyme markers at valuation of the gene lecular Biology, 22, 687-873. [2] Bouga M., Kilias G., Harizanis P., Papasotiropoulos pool of the mulberry silkworm and the obtained V. and Alahiotis S. 2005. Allozyme variability and results give us the grounds to draw the flowing phylogenetic relationships in honey bee (Hymenop- deductions and conclusions: tera: Apidae: A. mellifera) populations from Greece and Cyprus. Biochemical Genetics, 43, 471-484. Hexokinase (ÍÊ) is a suitable marker for • [3] Chatterjee S.N., Datta R.K. 1992. Hierarchical analyzing interbreed polymorphism and breed clustering of 54 races and strain of mulberry silkworm, differentiation. Bombyx mori: Significance of biochemical parameters. * Phosphoglucomutase (PGM) and malate de- Theoretical Applications of Genetics, 85, 394J402. [4] Chatterjee S.N., Rao C., Chatterjee G.K., hydrogenase (MDH) are more suitable for study-
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Ashwath S.K., Patnaik, AK. 1993. Correlation between study of local Bulgarian bee. Works of Bulgarian yield and biochemical parameters in the mulberry silk- Naturalistic society, 6,156-158. worm, Bombyx mori L. Theoretical Applications of [21] Marcato S., Trevisan M., Cappellozza L., Bisol P. Genetics, 87, 385 - 391. 1990. Variabilita di sistemi gene-enzima, in razze di [5] Daevis B. 1964. Disc electrophoresis. Methods Bombyx mori (Lepidoptera, Bombycidae) utilizzate per and application to human serum proteins. Ann. N. Y. la produzione di seta. Estratto da Redia, LXXIII (2): Acad. Sci., 121 (4), 404-427. 595-608. [6] Dedej S., Basiolo A. and Piva R. 1996. [22] Nei M. 1972. Genetic distance between Morphometric and alloenzymatic characterisation in populations. The American Naturalist, 106, 283-291. the Albanian honeybee population Apis mellifera L. [23] Petrov P. 1990. Characteristic and taxonomy Apidologie, 27, 121-131. of Bulgarian honey bees. PhD Dissertation, Moscow [7] Eaton G.M., Brewer G.J., Tashian R.E. 1966. Hex- University Press, Moscow, USSR. pp 133. okinase isozyme patterns of human erythrocytes and [24] Petrov P. 1995. Bulgarian honey bee Apis leucocytes. Nature. 212 (5065): 944-946. mellifica rodopica and race standard. Agrarian Univer- [8] Egorova Ò., Nasirillaev Y. 1993. Polymorphic en- sity of Plovdiv, Scientific works, X (3), 317-319. zymes of silkworm and their using in the selection. [25] Petrov P. 1996. Possibilities for using some State committee of science and technics of quantitative characteristics in the taxonomy of Bul- Uzbekistan, GFNTI: 120. garian honey bees Apis mellifera rodopica. Size of the [9] Eguchi M., Takahama Y., Ikeda M., Horii S. 1988. forewing. Journal of Animal Sciences, 4, 75-77. A novel variant of acid phosphatase isozyme from [26] Petrov P. 2000. Biology of A. mellifera rodopica hemolymph of the silkworm, Bombyx mori. Jpn. J. Ge- drones. Journal of Animal Sciences, 5-6, 81-92. netics, 63, 149-157. [27] Shaw C., Prasad R. 1970. Starch gel electro- [10] Felsenstein J. 1993. PHYLIP (Phylogeny Infer- phoresis of enzymes - A compilation of Recipes. ence Package), Version 3.5C Distributed by the author. Biochem. Genet., 4, 297 - 320. Dept. of Genetics, Univ. of Washington, Seattle, W.A. [28] Sneath P.H.A., Sokal R.R. 1973. Numerical Tax- [11] Goldsmith M.R. 1995. Genetics of the silkworm: onomy - The principle and practice of numerical clas- revisiting an ancient model system. In: Molecular sification. W.H. Freeman and Co., San Francisco. Model Systems in the Lepidoptera (Goldsmith MR and [29] Spencer N., Hopkinson D.A., Harris H. 1964. Wilkins AS, editors), Cambridge University Press, New Phosphoglucomutase polymorphism in man. Nature, York. pp 21-76. 204, 742-745. [12] Ivanova E. 1996. Variability of Apis mellifera in [30] Staykova T. 2006. Genetic control of phos- Bulgaria - ontogenetic and population-genetic aspects, phoglucomutase in mulberry silkworm (Bombyx mori PhD Dissertation, University of Plovdiv, Bulgaria. L.). International Jubilee Scientific Conference Prob- [13] Ivanova E. 2010. Investigation on genetic vari- lems of maintenance and utilization of mulberry and ability in honeybee populations from Bulgaria, Greece silkworm genetic resources, September 25 - 29, 2006, and Serbia. Biotechnology & Biotechnological Equip- Vratza, Bulgaria, 197-201. ment, 24, 385-389. [31] Staykova T. 2008. Genetically-determined [14] Ivanova E. and Bouga M. 2009. Genetic vari- polymorphism of non-specific esterases and phos- ability in honey bee population from Northern Bul- phoglucomutase in eight introduced breeds of the garia. Proceedings of the 41st Congress Apimondia, 15- silkworm, Bombyx mori, raised in Bulgaria. 8pp. Jour- 20 September, 2009, Montpelier - France (http:// nal of Insect Science, 8:18, available online: www.apimondia.org/2009/proceedings.htm). insectscience.org/8.18. [15] Ivanova E., Bienkowska M. and Petrov P. 2011. [32] Staykova T., Grekov D., Panayotov M. 2004. Allozyme Polymorphism and Phylogenetic Relation- Electrophoretic analysis of non-specific esterases in ships in Apis mellifera Subspecies Selectively Reared silkworm (Bombyx mori L.) female genital organs and in Poland and Bulgaria. Folia biologica (Krakow), eggs. International Journal of Industrial Entomology, 59,(3-4), 121-126. doi:10.3409/fb59_3-4.09-13. 9 (1), 59-63. [16] Ivanova E., Petrov P., Bouga M., Emmanouel N., [33] Stoykova T., Popov P., Dimitrov B. 2003. Elec- Ivgin-Tunka R. and Kence M. 2010b. Genetic Variation trophoretic analysis of non-specific haemolymph in Honey Bee (Apis mellifera L.) Populations from Bul- esterases during silkworm (Bombyx mori L.) ontogen- garia. Journal of Apicultural Science, 54 (2), 49-60. esis. Sericologia, 43 (2), 153-162. [17] Ivanova E., Staykova T. and Bouga M. 2007. [34] Swofford D.L., Selander R.B. 1981. BIOSYS-1: A Allozyme variability in honey bee populations from computer program for the analysis of allelic variation some mountainous regions in southwest of Bulgaria. in genetics Rel. 1.0 Department of Genetics and De- Journal of Apicultural Research, 46 (I), 3-8. velopment, University of Illinois at Urbana-Champaign, [18] Ivanova E., Staykova T. and Petrov P. 2010a. Urbana, Illinois 60801, USA. Allozyme variability in populations of local Bulgarian [35] Wright S. 1965. The Interpretation of popula- honey bee. Biotechnology & Biotechnological Equip- tion structure by F-Statistics with special regard to ment, 24 (2), 371 - 374. systems of mating. Evolution, 19, 395 - 420. [19] Lazarov A. 1935. Length of the honey bee [36] Yanagawa H. 1978. Tissue distribution, proboscis, importance and approaches for its measur- purifications, and properties of multiple forms of hex- ing. Bee., 6,156-158. okinase in the silkworm, Bombyx mori. Insect Biochem- [20] Lazarov A. 1936. Brief contribution for the istry, 8 (4): 293-305.
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ÎÒÍÎÑÍÎ ÃÅÍÅÒÈ×ÍÀÒÀ ÈÇÌÅÍ×ÈÂÎÑÒ È (MDH 1, ME, EST 3, ALP, PGM è HK). Êîíñòàòèðàí å ÈÇÏÎËÇÂÀÍÈÒÅ ÃÅÍÅÒÈ×ÍÈ ÌÀÐÊÅÐÈ ÇÀ ïîëèìîðôèçúì ïî âñè÷êèòå øåñò èçñëåäâàíè ÕÀÐÀÊÒÅÐÈÇÈÐÀÍÅ ÍÀ ÏÎÏÓËÀÖÈÈ A. ëîêóñè, êàêòî ñëåäâà: òðè àëåëà - çà MDH-1, ALP è MELLIFERA L. È ÏÎÐÎÄÈ B. MORI L.  HK ëîêóñèòå; ÷åòèðè - çà ME è PGM ëîêóñèòå è ÁÚËÃÀÐÈß øåñò - çà EST-3 ëîêóñà. Îò÷åòåíè ñà èçîåíçèìíè ãåíåòè÷íè ìàðêåðè, ïîäõîäÿùè çà èçïîëçâàíå ïðè Òåîäîðà Ñòàéêîâà, Åâãåíèÿ Èâàíîâà õàðàêòåðèçèðàíå íà áúëãàðñêèòå ìåäîíîñíè ï÷åëè. Ïëîâäèâñêè óíèâåðñèòåò Ïàèñèé Õèëåíäàðñêè, ×ðåç èçñëåäâàíå íà òðè èçîåíçèìíè ñèñòåìè Êàòåäðà Áèîëîãèÿ íà ðàçâèòèåòî, Ñåêöèÿ Ãåíåòèêà (PGM, MDH è HK) e ïðîâåäåí ãåíåòè÷åí àíàëèç íà óë. Öàð Àñåí 24, 4000 Ïëîâäèâ 10 ïîðîäè ÷åðíè÷åâà êîïðèíåíà ïåïåðóäà B. mori Òåë.: +359 261 549; Ôàêñ: +359 32 62 41 47 L. Óòî÷íåíè ñà ïîäõîäÿùè èçîåíçèìíè ìàðêåðè çà E-mail: [email protected]; geneiv@uni- îöåíêà íà âúòðåïîðîäíèÿ è ìåæäóïîðîäåí ïîëè- plovdiv.bg ìîðôèçúì è ïîðîäíàòà äèôåðåíöèàöèÿ ïðè òîçè âèä. Èçñëåäâàíè ñà ôèëîãåíåòè÷íèòå âðúçêè. Óñòà- Ðåçþìå íîâåíî å, ÷å ïîðîäèòå E 27, Japanese 106 è Jena ìîãàò Ïðîó÷åíà å ãåíåòè÷íàòà èçìåí÷èâîñò â ïîïóëà- äà ñå èçïîëçâàò â áúäåùè ñåëåêöèîííè ïðîãðàìè öèè ìåäîíîñíè ï÷åëè îò öÿëàòà ñòðàíà ÷ðåç èçî- êàòî äîíîðíè ïîðîäè, òúé êàòî ñà ãåíåòè÷íî îòäà- åíçèìåí àíàëèç ïî øåñò èçîåíçèìíè ñèñòåìè ëå÷åíè îò âñè÷êè îñòàíàëè.
IMMUNOMODULATORY EFFECTS OF SELECTED LACTOBACILLUS STRAINS AGAINST INFLAMMATION IN HUMAN INTESTINES
Zhechko Dimitrov LB-Bulgaricum Plc. R&D Center 12-A, Malashevska Str., 1000 Sofia, Bulgaria E-mail: [email protected]
Abstract plete the information about anti-inflammatory The aim of the present study was to evalu- potential of the strains, they were evaluated in ate the effect of LAB strains on IL-8 secretion in induction of IL-10 using macrophage cell line intestinal epithelia with/ without stimulation by model U-937. The strains B. longum Bif8, L. TNF-alpha. gasseri G8, E. faecalis E2 induced the production Intestinal epithelium is capable of releasing of IL-10 - 3.2, 2.1, and 0.2 ng/ml, respectively. some proinflammatory cytokines such as IL-8, es- It was proven that some LAB strains inhibit pecially when stimulated by cytokines like TNF- the secretion of IL-8 from epithelial cells. These alpha and IL-1. Some Lactic acid bacteria (LAB) strains will be included in products for further strains could modulate intestinal mucosal im- clinical trials of their anti-inflammatory effect. mune response playing anti-inflammatory role in INTRODUCTION the intestinal immune signaling. Intestinal epithelium is an important factor of A large number of strains with yoghurt and gut mucosal barrier, and participates in innate im- intestinal origin were evaluated in their ability to munity. Intestinal epithelia are capable of releas- reduce the production of IL-8 from human epi- ing some proinflammatory cytokines such as IL- thelium cell line Caco-2. The strains demonstrat- 8 when stimulated by cytokines like TNF-a, and ing the highest reduction of IL-8 after stimula- can response to enteric pathogens and release tion of epithelium cells with TNF-alpha were: B. some proinflammatory cytokines which in turn longum Bif8, L. gasseri G8, E. faecalis E2, L. direct the movement of inflammatory cells of bulgaricus B67, and S. thermophilus T43. It the lamina propria [8]. Probiotics, including should be noted the yoghurt origin of the latest bifidobacterium, lactobacillus play an essential two strains. The stimulation index of these role in the completeness of intestinal mucosa strains was between 0.6 and 0.8 in presence of barrier. For example, some probiotic strains could TNF-alpha, and between 0.94 and 1.07 without modulate intestinal mucosal immune response, co-stimulation with TNF-alpha. In order to com- some could play protective roles by inhibiting the
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National Scientific Programmes with European Dimensions
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ adhesion of pathogenic bacteria to intestinal washed three times with PBS pH 7.4, to remove epithelia [6]. The present study was to investi- culture medium and non-adherent cells. The bac- gate the effect of probiotics on IL-8 secretion of teria in culture medium were transferred into intestinal epithelium induced by TNF-a, and its individual wells respectively. TNF-a (10 ng/ml) possible mechanism. Additionally, selected LAB was added into each well of groups T and L 1 strains were evaluated in induction of IL-10 us- hour later. The supernatants were collected and ing macrophage cell line model U-937. centrifuged for measurement of IL-8 after 3 MATERIALS AND METHODS hours. Bacteria Different strains LAB, previously U-937 cells were grown in RPMI with 10% identified at strain level by help of pulsed field fetal calf serum. The cells were differentiated to gel electrophoresis [5], were provided by the macrophages by help of phorbol-myristate-ac- laboratory LBB collection in LB Bulgaricum PLC. etate (PMA) at final concentration of 1 mkg/ ml. The strains were grown at 37 in static, non-aer- The adhered macrophages were washed with ated BHI-agar to reach the mid-log phase. Bac- PBS pH 7.4 to remove PMA and non-adherent teria were harvested by centrifugation at 2 500 cells. The bacteria in culture medium were trans- g for 15 min at 20 . After two washes in sterile ferred into individual wells respectively. The PBS pH 7.4, at 25 , the bacteria were resuspended supernatants were collected and centrifuged for in PBS. Cell counts in the bacteria suspension measurement of IL-10 after 18 hours. were estimated by optical density at 600 nm IL-8 enzyme-linked immunosorbent as- absorbance (BioMerieux, Germany). Then the says IL-8 enzymelinked immunosorbent assays bacteria were added to the cell culture wells at (ELISA) were performed according to the manu- appropriate dilution to reach a final concentra- facturers instructions. In short, polyclonal goat tion of 108 cfu/ml of medium. anti-human IL-8 antibodies were used as captur- Cells and bacteria coculture Caco-2 cells ing antibodies, biotinylated polyclonal rabbit anti- were grown in DMEM with 10% fetal calf serum, human IL-8 antibodies as detecting antibodies. and divided into four groups: control, TNF-a Streptavidin-HRP and TMBS were added as color (group T in short), LAB group (group L). When indicator. Plates were read at 450 nm of wave- grown to confluence in single layer, cells were length right after color reaction was stopped
Fig. 1. Concentrations of IL-8 in each group (mean±SD). Natural interleukin-8 expression was seldom found in Caco-2 cells of the control group. When stimulated by TNF-a (10 ng/ml), Caco-2 cells se- creted a large number of IL-8, and the concentration of IL-8 in group T was significantly increased than that in control (P<0.001). However, there was some difference in the concentration of IL-8 among group T and L. There was less interleukin-8 secretion in Caco-2 cells when preincubated with selected LAB strains (group L) compared with group T (P=0.002, 0.01, respectively).
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Advances in Bulgarian Science
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with acid. All procedures were performed at pathogens [13]. Aberrance of gut microflora has room temperature. been reported in IBD and acute gastroenteritis [7, IL-10 enzyme-linked immunosorbent as- 16]. The aberrant microflora disregulates mu- says IL-10 enzymelinked immunosorbent assays cosal immune reaction. Invasion of some virulent (ELISA) were performed according to the manu- strains into epithelia could break down the integ- facturers instructions (Diaclone, USA). rity of intestinal mucosa, and induce inflamma- RESULTS AND DISCUSSION tory cell infiltration [18]. Some researchers found IL-8 secretion. Concentrations of IL-8 in that manipulating the normal intestinal flora us- supernatants of each group are shown in Figure ing probiotics had a beneficial effect on health 1. The concentration of IL-8 in control was only by altering the microbial environment, and some 172.2±42.1 ng/L. When stimulated by TNF-a, components of the flora could down-regulate Caco-2 cells secreted a large number of IL-8, and inflammation when supplemented to patients the concentration of IL-8 in group T was with gastrointestinal diseases [11, 17]. Some stud- 639.5±62.3 ng/L. However, when preincubated ies have been undergoing to explore the possi- with different LAB strains, Caco-2 cells produced ble mechanisms of probiotic action on gut epi- either the same quantity or less IL-8, compared thelium and mucosal immune system. In order to with group T. The concentrations of IL-8 were imitate the inflammatory condition of gut in vitro, 383.8±76.7 ng/L, 397.2±71.5 ng/L, 412.1±68.6 we used TNF-a to stimulate human colonic ad- ng/L, 492.1±56.6 ng/L, 511.4±55.4 ng/L in group enocarcinoma Caco-2 cells, which has basically L for the strains B. longum Bif8, L. gasseri G8, E. the same biological properties as normal colonic faecalis E2, L. bulgaricus B67, and S. thermophilus epithelia. As some probiotic strains could adhere T43, respectively. to human intestinal cell surface [2, 3], five Intestinal epithelia constitute mucosal barrier probiotic strains B. longum Bif8, L. gasseri G8, E. of the bowel, and participate in inflammatory or faecalis E2, L. bulgaricus B67, and S. thermophilus immune responses in gut [4, 10]. In some T43, inhibited the secretion of IL-8 in Caco-2 cells gastrointestinal infectious and inflammatory when stimulated with TNF-a one hour after conditions, such as inflammatory bowel disease coculture with the five probiotic strains. It indi- (IBD), acute gastroenteritis, inflammatory cells cated that the strains could trigger anti-inflam- including monocytes, lymphocytes, were activated matory pathways within the gut epithelium. The and accumulated in lamina propria. The cells se- epithelia attached to the strains showed immune crete excessive inflammatory products, such as hypo reaction to TNF-a, and produced less IL-8. TH1 type cytokines, chemokines and a lot of ac- IL-10 secretion. As the induction of the tive oxides. Overproduction of cytokines could cytokine IL-10 is recognized to be anti-inflamma- affect the biological action of epithelial cells. For tory, we evaluated the IL-10 induction effect by instance, TNF-a could induce epithelial cells to the five LAB strains, which previously demon- secrete IL-8, and express membrane Toll-like strated the best inhibition of the synthesis of IL- receptor 4 (TLR4) excessively [12, 20]. TLR4 could 8, on differentiated to macrophage U-937 cell enable intestinal epithelia hyper reactive in re- line. Concentrations of IL-10 in supernatants of sponse to lipopolysaccharides (LPS), the compo- each group are shown in Figure 2. nent of bacteria walls, and IL-8 had leukocytes When stimulated by the five LAB strains, U- chemotactic and stimulatory properties [1]. As 937 cells secreted a different quantity of IL-10. more inflammatory cells infiltrate, the inflamma- The concentration of IL-10 when U-937 cells tory reaction is therefore amplified. The normal were preincubated with the five previously se- flora of human gastrointestinal tract contains lected LAB strains, demonstrating the best inhibi- diverse populations of bacteria which play an tion of IL-8, was 3.2, 2.1, 0.2, 0.05, and 0.0 ng/ml essential role in the development of gut mucosal for the strains B. longum Bif8, L. gasseri G8, E. barrier and innate immunity. Some intestinal faecalis E2, L. bulgaricus B67, and S. thermophilus microflora could exert a protective role against T43, respectively.
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National Scientific Programmes with European Dimensions
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Fig. 2. Concentrations of IL-10 induction by the five best IL-8 inhibitors
CONCLUSIONS [5] Dimitrov Zh. Development of strain discrimina- The selected five LAB strains successfully in- tive AFLP for Bifidobacteria. Design of strain-specific markers. Biotechnology and Biotechnological Equip- hibited IL-8 secretion in intestinal epithelia in the ment, Special issue, 25/2011, in-press experiment. At present, some probiotic com- [6] Dimitrov Zh. Evaluation of cholesterol-reduc- pounds have been used in management of some tion activity of lactic acid bacteria and yeasts from diseases, such as maintenance therapy in IBD [9, fermented milks. Food science, engineering and tech- nologies, 2011, LVIII: 31-36 15]. Although the mechanism of probiotic action [7] Duchmann R., Kaiser I., Hermann E., Mayet W., has not been fully understood, the beneficial ef- Ewe K., Meyer zum Buschenfelde K.H. Tolerance ex- fects were consistent with an anti-inflammatory ists towards resident intestinal flora but is broken in active inflammatory bowel disease (IBD). Clin Exp state conferred by probiotics [14, 19]. These five Immunol 1995; 102: 448-455 LAB strains will be included in products for fur- [8] Gewirtz A.T., McCormick B., Neish A.S., Petasis ther clinical trials of their anti-inflammatory ef- N.A., Gronert K., Serhan C.N., Madara J.L. Pathogen-in- duced chemokine secretion from model intestinal epi- fect. thelium is inhibited by lipoxin A4 analogs. J. Clin In- vest 1998; 101: 1860-1869. References [9] Gionchetti P., Rizzello F., Venturi A., Brigidi P., [1] Aderem A., Ulevitch R.J. Toll-like receptors in the Matteuzzi D., Bazzocchi G., Poggioli G., Miglioli M., induction of the innate immune response. Nature Campieri M. Oral bacteriotherapy as maintenance 2000; 406: 782-787 treatment in patients with chronic pouchitis: a double- [2] Adlerberth I., Ahrne S., Johansson M.L., Molin G., blind, placebo-controlled trial. Gastroenterology 2000; Hanson L.A., Wold A.E. A mannose-specific adherence 119: 305-309 mechanism in Lactobacillus plantarum conferring [10] Gordon J.I., Hooper L.V., McNevin M.S., Wong M., binding to the human colonic cell line HT-29. Appl Bry L. Epithelial cell growth and differentiation. III. Environ Microbiol 1996; 62: 2244-2251 Promoting diversity in the intestine: conversations be- [3] Bernet M.F., Brassart D., Neeser J.R., Servin A.L. tween the microflora, epithelium, and diffuse GALT. Lactobacillus acidophilus LA 1 binds to cultured hu- Am J Physiol 1997; 273(3 Pt 1): G565-G570 man intestinal cell lines and inhibits cell attachment [11] Guandalini S. Use of Lactobacillus-GG in pae- and cell invasion by enterovirulent bacteria. Gut 1994; diatric Crohns disease. Dig Liver Dis 2002; 34 (Suppl 35: 483-489 2): S63-65 [4] Campbell N., Yio X.Y., So L.P., Li Y., Mayer L. The [12] Hausmann M., Kiessling S., Mestermann S., intestinal epithelial cell: processing and presentation Webb G., Spottl T., Andus T., Scholmerich J., Herfarth H., of antigen to the mucosal immune system. Immunol Ray K., Falk W., Rogler G. Toll-like receptors 2 and 4 are Rev 1999; 172: 315-324 up-regulated during intestinal inflammation. Gastro-
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enterology 2002; 122: 1987-2000 ÈÌÓÍÎÌÎÄÓËÈÐÀÙÈ ÅÔÅÊÒÈ ÍÀ [13] Isolauri E., Kirjavainen P.V., Salminen S. ÑÅËÅÊÒÈÐÀÍÈ ÙÀÌÎÂÅ ËÀÊÒÎÁÀÖÈËÈ Probiotics: a role in the treatment of intestinal infec- ÑÐÅÙÓ ÈÍÔËÀÌÀÖÈÈ Â ÈÍÒÅÑÒÈÍÀËÍÈß tion and inflammation? Gut 2002; 50 (Suppl 3): III54- ÒÐÀÊÒ 59 [14] Madsen K.L., Doyle J.S., Jewell L.D., Tavernini Æå÷êî Äèìèòðîâ M.M., Fedorak R.N. Lactobacillus species prevents coli- ÅëÁè Áóëãàðèêóì ÅÀÄ, Íàó÷íîèçñëåäîâàòåëñêè tis in interleukin 10 gene-deficient mice. Gastroenter- öåíòúð ology 1999; 116: 1107-1114 óë. Ìàëàøåâñêà ¹ 12-À, 1000 Ñîôèÿ [15] Malin M., Suomalainen H., Saxelin M., Isolauri E. Promotion of IgA immune response in patients with Ðåçþìå Crohns disease by oral bacteriotherapy with Lactoba- Öåëòà íà èçñëåäâàíåòî å äà ñå îöåíè åôåêòà íà cillus GG. Ann Nutr Metab 1996; 40: 137-145 ùàìîâå ëàêòîáàöèëè âúðõó ñåêðåöèÿòà íà èí- [16] Masseret E., Boudeau J., Colombel J.F., Neut C., òåðëåâêèí 8 (IL-8) îò èíòåñòèíàëíèÿ åïèòåë ñ è áåç Desreumaux P., Joly B., Cortot A., Darfeuille-Michaud A. ñòèìóëèðàíå ñ òóìîð-íåêðîçèñ àëôà (TNF-alpha). Genetically related Escherichia coli strains associated Èíòåñòèíàëíèÿò åïèòåë å ñïîñîáåí äà ñèíòåçèðà with Crohns disease. Gut 2001; 48: 320-325 íÿêîè ïðîèíôëàìàòîðíè öèòîêèíè êàòî IL-8, [17] Rembacken B.J., Snelling A.M., Hawkey P.M., îñîáåíî â ïðèñúñòâèå íà TNF-alpha è IL-1. Íÿêîè Chalmers D.M., Axon A.T. Non-pathogenic Escherichia ìëå÷íîêèñåëè áàêòåðèè (ÌÊÁ) ìîãàò äà ìîäóëè- coli versus mesalazine for the treatment of ulcerative ðàò èíòåñòèíàëíèÿ èìóíåí îòãîâîð, èãðàåéêè àíòè- colitis: a randomized trial. Lancet 1999; 354: 635-639 èíôëàìàòîðíà ðîëÿ. [18] Resta-Lenert S., Barrett K.E. Enteroinvasive  íàñòîÿùîòî èçñëåäâàíå ãîëÿìà ãðóïà ùàìîâå bacteria alter barrier and transport properties of hu- ñ èíòåñòèíàëåí è êèñåëîìëå÷åí ïðîèçõîä áÿõà man intestinal epithelium: role of iNOS and COX-2. èçïèòàíè ïî îòíîøåíèå ñïîñîáíîñòòà èì äà ïîíè- Gastroenterology 2002; 122: 1070-1087 æàâàò ïðîäóêöèÿòà íà IL-8 îò ÷îâåøêàòà åïèòåëíà [19] Shibolet O., Karmeli F., Eliakim R., Swennen E., êëåòú÷íà ëèíèÿ Caco-2. Ùàìîâåòå, êîèòî äåìîí- Brigidi P., Gionchetti P., Campieri M., Morgenstern S., ñòðèðàõà íàé-âèñîêà ðåäóêöèÿ íà ïðîäóêöèÿòà íà Rachmilewitz D. Variable response to probiotics in two IL-8 ñëåä ñòèìóëèðàíå íà åïèòåëíèòå êëåòêè ñ TNF- models of experimental colitis in rats. Inflamm Bowel alpha ñà: B. longum Bif8, L. gasseri G8, E. faecalis E2, L. Dis 2002; 8: 399-406 bulgaricus B67, è S. thermophilus T43. Òðÿáâà äà ñå [20] Wolfs T.G., Buurman W.A., van Schadewijk A., îòáåëåæè êèñåëîìëå÷íèÿò ïðîèçõîä íà ïîñëåäíèòå de Vries B., Daemen M.A., Hiemstra P.S., vant Veer C. äâà ùàìà. Ñòèìóëèðàùèÿò èíäåêñ íà ãîðåñïîìåíà- In vivo expression of Toll-like receptor 2 and 4 by re- òèòå ùàìîâå áå â äèàïàçîíà 0.6-0.8 â ïðèñúñòâèå íà nal epithelial cells: IFN-g and TNF-a mediated up- TNF-alpha, è ìåæäó 0.94 è 1.07 â îòñúñòâèå íà TNF- regulation during inflammation. J Immunol 2002; 168: alpha. Çà äà ñå äîïúëíè îöåíêàòà çà àíòèèíôëàìà- 1286-1293 òîðíèÿ ïîòåíöèàë íà ùàìîâåòå, òå áÿõà èçïèòàíè çà ñïîñîáíîñòòà èì äà èíäóöèðàò ïðîèçâîäñòâîòî íà IL-10 îò ìàêðîôàãîâàòà êëåòú÷íà ëèíèÿ U-937. Ùàìîâåòå B. longum Bif8, L. gasseri G8, E. faecalis E2 èíäóöèðàõà ñèíòåçà íà IL-10 - 3.2, 2.1, and 0.2 ng/ml, ñúîòâåòíî. Äîêàçàíî áå, ÷å íÿêîè ùàìîâå ÌÊÁ èíõèáèðàò ñåêðåòèðàíåòî íà IL-8 îò åïèòåëíè êëåòêè. Òåçè ùàìîâå ùå ñå âêëþ÷àò â ïðîäóêòè çà áúäåùè êëè- íè÷íè èçïèòàíèÿ íà òåõíèÿ àíòèèíôëàìàòîðåí åôåêò.
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National Scientific Programmes with European Dimensions
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IMMOBILIZATION OF TRICHOSPORON CUTANEUM R57 CELLS
ONTO SiO2/HPC HYBRID MATERIALS AND REMOVAL OF Mn2+ IONS
Nelly Georgieva, Dimitar Peshev, Nadezhda Rangelova, Nevena Lazarova, Tsvetelina Angelova University of Chemical Technology and Metallurgy 8, Kl. Ohridski Blvd., 1756 Sofia, Bulgaria Phone: +359 2 8163307; E-mail: [email protected]
Abstract effect. Exposure to high concentrations of man- New silica hybrid materials containing ganese leads to manganism, Parkinsons disease tetraethoxy siloxane (TEOS) as inorganic precur- and Alzheimers [1]. The importance of microbial sor and hydroxypropyl cellulose (HPC) as an or- activity in the remediation of Mn-contaminated ganic compound were prepared. The quantity of waters was frequently observed. Several strains organic substance was 5 and 50 wt% to silica. of Mn2+-oxidizing bacteria were used for treat- The structure of obtained hybrids was investi- ment of manganiferous mine waters [2]. Mariner gated by FT-IR and SEM analysis. The synthe- et al. [3] identified Mn2+-oxidizing fungi in addi- sized hybrid materials were applied as matrices tion to bacteria, useful for treatment of mine for cells immobilization by attachment of waters. filamentous yeast Trichosporon cutaneum R57. Metal remediation through common physico- This strain showed considerable ability to remove chemical techniques is not efficient in case of ef- manganese ions from aqueous solutions. The fluents containing complexing organic matter experimental data on the equilibrium specific and low metal contamination [4]. Microbial uptake with free strain cells were used to plot remediation of metal ions can be either catalytic the adsorption isotherm. Kinetic experiments on or non-catalytic. It precedes through four differ- biosorption of manganese ions with immobilized ent mechanisms, namely biosorption, bioaccumu- cells were performed at Mn2+ initial concentra- lation, redox reaction and complex formation [5]. tions 275 and 550 mg/L. These values were se- Bioremediation techniques include cellular se- lected based on the free strain cells perform- questration and accumulation, or extra-cellular ance shown by the adsorption isotherm. A precipitation. Microorganisms provide a large pseudo second order kinetic model was em- contact area that can interact with metals in the ployed to fit the experimental data. Higher spe- surrounding environment [6, 7]. The microbial cific uptake was established with immobilized biomass contains chemically active sites that are cells and higher content of HPC in the immobili- responsible for sequestering metals from the zation material. surrounding solution [4]. The heavy metal toler- ance of the microorganisms depends on their INTRODUCTION ability to sustain toxic ions by absorbtion to Heavy metal pollution due to anthropological metabolically less active compartments such as practices represents an important environmental cell walls or vacuoles, or by evolving an effective problem - more toxic metal ions are released in mechanism for ion extrusion outside of the cells the nature and disrupt the ecosystem. Manga- [8]. Living microorganisms have been effectively nese is an essential transition metal that is re- immobilized in silica sol-gel matrices, and success- quired by organisms ranging from simple bacte- fully used for preparation of heavy metal bio- ria to humans. Manganese function is a compo- sorbents [9-15]. High potential of Trihosporon nent of several enzymes involved in carbohy- cutaneum strain R57 for heavy metals removal - drate, lipid and protein metabolism. High copper, cadmium and chromium from contami- amounts of Cd2+, Cu2+ and Mn2+ ions have a toxic nated waters has been revealed in several previ-
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ous investigations [16-19]. The immobilization the specific heavy metal uptake, trough attachment on the surface of hybrid where q is the quantity of metal ions adsorbed matrices (although decreasing the specific rate by a given quantity of biosorbent (mg g-1) in of the process) has been shown to retain the time t (min); V is the volume of the liquid phase high strain biosorption capacity [19]. (L); C is the concentration of metal ions, mg L-1; - The goal of the present work is to study the C0 is the initial concentration of metal ions, mg L 1 properties of new SiO2/hydroxypropyl cellulose and m is the biosorbent dry weight (g). To de- hybrid matrices and their suitability for Trichos- termine the kinetic parameters for the adsorp- poron cutaneum strain R57 cell immobilization, tion of manganese ions by immobilized cells of aiming removal of manganese ions from waste the studied strain, the experimental data were waters. used to fit a pseudo second order kinetic model MATERIALS AND METHODS (Eq. (1)). Microorganisms and growth conditions Filamentous yeast strain Trichosporon (1) cutaneum R 57 maintained in the culture collec- tion of Bulgarian National Bank of Industrial Mi- The values for the equilibrium heavy metal
croorganisms and Cell Cultures under N2414 uptake qeq (metal uptake concentration at equi- was used in this study. The cultivation was car- librium, mg.g-1) and the specific adsorption rate -1 -1 ried out in a medium under conditions described constant kads (g mg min ) were determined elsewhere [7]. from the slope and the intercept of the plot t/q
Hybrid materials preparation versus t. The equilibrium parameter qeq, which is A pre-hydrolyzed solution of tetraethoxy a characteristic for the specific uptake capacity siloxane (TEOS) with H O and HCl was prepared, (i.e. the efficiency) of the biosorbent and the 2 then dissolved pectin was added and pH was rate constant provide tools for process evalua- adjusted to 7 by phosphate buffer. The molar tion and engineering. -3 ratio SiO2:H2O:C2H5OH:HCl was 1:2:8:1x10 . The Analytical measurements hybrids contained 5 and 50 wt% HPC to silica. Structural groups of the obtained hybrid ma- The hybrid materials were aged at room tem- terials were determinated by a Fourier Transform perature and used as matrices for cells immobi- infrared (FT-IR) spectroscopy with MATSON lization. 7000 Fourier Transforming Infra-Red spectrome- Cells immobilization and biosorption ex- ter using KBr tablets. Scanning electron micro- periments scopy (SEM) was employed to study the mor- Biosorption of manganese ions was per- phology of the obtained hybrids. SEM images formed in a batch system as described previously were taken with a Microscope LEO 1530, Gemini [19]. Immobilization of cells by attachment was at an acceleration voltage of 10 kV. The obtained carried out at the 6th hour of the strain cultiva- materials were covered with gold using BAL- tion when the hybrid materials were added to TEC/SCD 050 Sputter coater and subsequent the culture medium. In order to study the equi- degassing using Vacuum Pump Leybovac PT librium state and kinetics of biosorption by free 360/16 before the investigation. and immobilized cells, manganese ions were sup- Manganese ions concentration in the medium plied to the cultivated strain at the 24th hour of was measured by Prodigy High Dispersion ICP cultivation in the form of sulfates in concentra- Leeman Labs. After supplying manganese ions to
tions of 5 mM and 10 mM MnSO4. The cultiva- the cultivated strain, samples for ICP analysis tion experiments were carried out at 300C. were taken at every 5, 10, 15, 30, 60 and 120 min. The heavy metals biosorption was performed Before analysis, all samples were centrifuged to under vigorous stirring in order to restrict external remove the solids. diffusivity limitations. The experimental data for For microscope observations, the cells were the concentration of residual heavy metals in the washed twice with distilled water, stained with liquid phase at given time were used to calculate 2% solution of methylene blue for 20 min at
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○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ room temperature, washed again with distilled microheterogeneities are with average size water and dried for 24 hours at 37°Ñ. Further, ~0.5mm. The addition of 50 wt % HPC (Fig. 2, b) the samples were analyzed by using bright field led to formation of a homogeneous structure. microscope Olympus BX53, Camera SC30 (Ja- The hybrids have the so-called fracture struc- pan). ture, consisting of micro cracks, evenly distrib- RESULTS AND DISCUSSION uted in the matrix. The FT-IR spectra of the precursors and the obtained hybrids are illustrated in Fig.1. As it can be seen, the broad band at ~3400 cm-1 is due to Si-OH stretching on the surface of silanols hy- drogen and also due to vibration of Si-O-Si units [20-22]. The bands at 3210 cm-1 can be attrib- uted to silanol groups [20]. The band at ~1635 cm-1 can be attributed to vibration of H-O-H which interacts through hydrogen bonds with silanol groups. SiO network can be identified 2 with bands at around 1057 cm-1, 790 cm-1 and 460 cm-1 due to vibrations of Si-O-Si bonds [20]. The bands at ~940 cm-1 are attributed to Si-OH groups [21-24]. The main difference can be seen for the asymmetric bond at ~3260 cm-1 which becomes broader probably due to the formation of hydrogen bonding between organic and inor- ganic part [20-22].
Fig. 2. SEM images of SiO2/ HPC hybrid materials containing 5 wt% (1) and 50 wt% (2) cellulose ether
The equilibrium state during adsorption of manganese ions by free yeast cells was studied Fig. 1. FT-IR spectra of SiO derived from TEOS 2 in the range for the equilibrium concentration in (1), HPC (2) and obtained hybrids with 5 wt% the liquid phase, C , from 0 to 446 g/L. The ex- HPC (3) and 50 wt% (4) e perimental isotherm (Fig. 3) illustrates the de- The surface morphology and microstructure pendence of the equilibrium specific metal up- of the hybrid materials was observed by SEM take q on C . Up to concentration of 215 mg/ eq e (Fig. 2). From the SEM images it can be seen that L, the specific uptake increased monotonically. the hybrids containing 5 wt % cellulose ether For concentrations in the range from 215 to 380 have a smooth surface with wavy character and mg/L (from 5 to 8 mM) the function reaches heterogeneous inclusions, unevenly distributed in plateau and further increase in the ions concen- the main matrix. The formed tration in the liquid phase did not result in higher
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specific uptake. Additional adsorption was ob- morphology. The experimental data were fitted served at concentrations higher than 8 mM in to the second order Eq. (1). The results are sum- the liquid phase. marized in Table 1 and illustrated in Fig. 5.
Fig. 3. Experimental isotherm for biosorption of manganese ions by free cells of Fig. 5. Kinetics of manganese ions adsorption Trichosporon cutaneum strain R57 by immobilized Tr. cutaneum R57 cells
For industrial scale applications, it is very im- As it can be seen from Table 1, the correlation portant to immobilize the yeast cells on an inert coefficient, R values for the t/q vs. t plots are carrier while maintaining their activity. The feasi- sufficiently high in all cases (R>0.998), which bility of the proposed in this work materials and demonstrated the applicability of the second methodology for immobilization was proved by order kinetic model. The good model description series of kinetic experiments, which included im- is also supported by the observed negligible de- mobilization materials with 5% and 50 % con- viation between the measured equilibrium spe- tent of HPC at initial concentration of the Mn2+ cific uptake, exp , and the calculated one calc ions in the batch reactor 5 mM and 10 mM. qeq qeq
Fig. 4. Microscopic photographs of immobilized Tr. cutaneum R57 cells onto 50 wt% SiO2/ HPC hybrid materials; a- Control, b- in the presence of 5 mM MnSO , c- in the presence of 4
10 mM MnSO4. Bar is 20 µm As it can be concluded based on Fig. 4 and (less than 3%). indirectly from Fig. 3, the concentration of 5 mM A careful observation of the data presented can be considered as inhibitory threshold value. in Table 1, Figs. 3 and 5 reveals that the immobi- The concentration of 10 mM is moderate inhibi- lization of the cells not only retained but slightly tory value, since it was observed an abnormal increased their adsorption capacity. This effect is
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Table 1. Second order kinetic model parameters
Immobilizati C0,R on material mg l-1 min-1 mg g-1 mg g-1 HPC content, wt % %
5 275 0.9999 3.3366 1.308 1.3203 1.6 50 275 0.999 1.7049 1.5689 1.5357 2.2 5 550 0.9997 0.84946 2.8977 2.8158 2.9 50 550 0.9984 0.63087 3.3422 3.4376 2.8 more prominent with higher HPC content in the [3] Mariner R., Johnson D., Hallberg K. 2008. Char- acterisation of an attenuation system for the immobilization matrix (50% compared to 5%) remediation of Mn (II) contaminated waters. and higher initial concentration of the metal ions Hydrometallurgy 94:100-104. in the medium. [4] Gadd G., 1993. Interaction of fungi with toxic The biosorption process includes physico- metals. New Phytologist. 124:25-60. [5] Sujith P., Das A., Shashikant B., Bharathi L. 2011. chemical interactions between metal ions and Immobilization of manganese, cobalt and nickel by several anionic ligands present on the biomass deep-sea-sediment-microbial communities. Chem. such as carboxyl, phosphoryl, carbonyl and Ecol., 27 (3):189-206. [6] Pietrobelli J., Modenesk A., Espinoza-Quinones F., sulfhydryl groups. The results in this study Fagundes-Klen M., Kroumov A. 2009, Removal of cop- clearly supported the benefit of incorporating per ions by non-living aquatic macrophytes Egeria Trichosporon cutaneum strain R57 cells into the densa. - J. BioAutomation, 12:21-32. [7] Shah K., Nongkynrih J. 2007. Metal studied matrices for removal of manganese ions hyperaccumulation and bioremediation. Biologia from waste waters. Thus this study may be re- Plantarum, 51 (4):618-634. garded as an initial step in the development of [8] Hockertz S., Schmid J., Auling G. 1987. A specific technologies for bioremediation of waste water transport system for manganese in the filamentous fungus Aspergillus niger. J General Microbiol. polluted with heavy metals. 133:3513-3519. CONCLUSION [9] Alvarez G., Foglia M., Camporotondi D., The obtained encouraging results on enhanc- Tuttolomondo M., Desimone M., Diaz L. 2011. A func- tional material that combines the Cr(VI) reduction ing the biosorption capacity of the Tr. cutaneum activity of Burkholderia sp. with the adsorbent capac- R57 strain cells, the relatively high specific surface, ity of sol-gel materials. J. Mater. Chem. 21:6359-6364. appropriate physicochemical properties and me- [10] Soltmann U., Matys S., Kieszig G., Pompe W., Böttcher H. 2010. Algae-Silica Hybrid Materials for chanical stability of the synthesized hybrid ma- Biosorption of Heavy Metals. J. Water Resource and terials revealed the potential benefits from their Protection 2:115-122. application in industrial scale applications for [11] Çabuk A., Akar T., Tunali S., Tabak Ö. 2006 bioremediation of Mn2+ contaminated waste Biosorption characteristics of Bacillus sp. ATS-2 immo- bilized in silica gel for removal of Pb(II). Journal of waters. Hazardous Materials B 136:317-323. Acknowledgements [12] Menegario A., Smichowski P., Polla G. 2005. On- This work was supported by the National Sci- line preconcentration and speciation analysis of Cr(III) and Cr(VI) using bakers yeast cells immobilised on ence Fund (Ministry of Education of Bulgaria) controlled pore glass. Analytica Chimica Acta grant DDVU 02-96/20.12.2010. 546:244-250. [13] Chen J-P., Lin Y-Sh. 2007. Sol-gel-immobilized recombinant E. coli for biosorption of Cd2+. Journal of References the Chinese Institute of Chemical Engineers 38:235- [1] Barbulesku I., Rusu N., Rughinis R., Popa O., 243. Stefaniu A., Casarica A. 2010. Obtaining yeast biomass [14] de la Rosa G., Gardea-Torresdey J.L., Peralta- enriched with copper, zinc and manganese. Rom. Videa J.R., Herrera I., Contreras C. 2003. Use of silica- Biotechnol. Lett. 15:5008-14. immobilized humin for heavy metal removal from [2] Tebo B., Johnson H., McCarty J., Templeton A. aqueous solution under flow conditions Bioresource 2005. Geomicrobiology of manganese (II) oxidation. Technology 90:11-17. Trends Microbiol. 13:421-428. [15] Szilva J., Kuncova G., Patzak M., Dostalek P.
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1998. The Application of a Sol-Gel Technique to ÈÌÎÁÈËÈÇÈÐÀÍÅ ÍÀ TRICHOSPORON CUTANEUM R57 ÂÚÐÕÓ SiO Preparation of a Heavy Metal Biosorbent from Yeast 2/ Cells. J Sol-Gel Sci Technol 13:289-294. ÕÈÄÐÎÊÑÈÏÐÎÏÈËÖÅËÓËÎÇÀ ÕÈÁÐÈÄÍÈ [16] Georgieva N., 2008. Growth of Trichosporon ÌÀÒÅÐÈÀËÈ È ÎÒÑÒÐÀÍßÂÀÍÅ ÍÀ cutaneum R 57 in the presence of toxic concentration Mn2+ ÉÎÍÈ of cadmium and copper. Intern. J. Agr. and Biol. 10:325-328. Íåëè Ãåîðãèåâà, Äèìèòúð Ïåøåâ, Íàäåæäà [17] Georgieva N., Bryaskova R., Debuigne A., Ðàíãåëîâà, Íåâåíà Ëàçàðîâà, Öâåòåëèíà Detrembleur Ch. 2010. Cadmium and Copper Absorp- Àíãåëîâà tion Mediated by a Poly(vinyl alcohol)-b-Polyacry- Õèìèêîòåõíîëîãè÷åí è ìåòàëóðãè÷åí óíèâåðñèòåò lonitrile Based Micelle/ Trichosporon cutaneum Cell Áóë. Êë. Îõðèäñêè 8, 1756 Ñîôèÿ System, J. Appl. Polym. Sci, 116, (5):2970-2975. E-mail: [email protected] [18] Georgieva N., Peshev D., Rangelova N., Lazarova N. 2011. Effect of hexavalent chromium on growth of Ðåçþìå Trichosporon cutaneum R 57. J. Univ. Chem. Technol. Ñèíòåçèðàíè ñà íîâè õèáðèäíè ìàòåðèàëè, ñú- and Met., 46, 3:293-298. äúðæàùè òåòðàåòîêñè ñèëàí (TEOS), êàòî íåîðãà- [19] Rangelova N., Georgieva N., Peshev D., Yotova íè÷åí ïðåêóðñîð è õèäðîêñèïðîïèë öåëóëîçà L., Nenkova S. 2009. Immobilization of Trichosporon (HPC), êàòî îðãàíè÷åí êîìïîíåíò. Ñúîòíîøåíèåòî cutaneum R 57 cells onto methylcellulose/SiO2 hybrids íà îðãàíè÷íèÿ êîìïîíåíò áåøå 5 è 50 ìàñ. %. and biosorption of cadmium and copper ions. J. Ñòðóêòóðàòà íà ïîëó÷åíèòå õèáðèäè áå èçñëåäâàíà BioAutomation 13, 4:221-230. ñ ïîìîùòà íà èíôðà÷åðâåíà ñïåêòðîñêîïèÿ (FT-IR) [20] Rangelova N., Radev L., Nenkova S., Salvado è ñêàíèðàùà åëåêòðîííà ìèêðîñêîïèÿ (SEM). I.M., Fernandes M.H., Herzog M. 2011. Methylcellulose/ Ñèíòåçèðàíèòå õèáðèäíè ìàòåðèàëè áÿõà èçïîëç- SiO2 hybrids: sol-gel preparation and characterization âàíè êàòî íîñèòåëè çà êëåòú÷íà èìîáèëèçàöèÿ by XRD, FTIR and AFM. Cent Eur J Chem 9:112-118. ÷ðåç ïðèêðåïâàíå íà ôèëàìåíòîçíè äðîæäè Tri- [21] Rangelova N., Nenkova S., Chernev G., chosporon cutaneum R57. Òîçè ùàì å ïîêàçàë ñïî- Georgieva N., Yotova L., Salvado I., Herzog M. 2010. ñîáíîñò çà îòñòðàíÿâàíå íà ìàíãàíîâè éîíè. Îïèò- Synthesis, characterization and application of SiO2- íèòå äàííè çà ðàâíîâåñíàòà êîíöåíòðàöèÿ íà àä- methylcellulose hybrid materials; Nanoscience & ñîðáàòà ïðè èçïîëçâàíå íà ñâîáîäíè êëåòêè, êàòî Nanotechnology 10, eds. E. Balabanova, I. Dragieva, àäñîðáåíò, ñà èçïîëçâàíè çà ïîñòðîÿâàíå íà àä- Heron Press Sofia, 172-174. ñîðáöèîííàòà èçîòåðìà. Ïðîâåäåíè ñà êèíåòè÷íè [22] Kim J., Chang S., Kong S., Kim K., Kim J., Kim W. åêñïåðèìåíòè ïî áèîñîðáöèÿ íà ìàíãàíîâè éîíè 2009. Control of hydroxyl group content in silica par- ñ èìîáèëèçèðàíè êëåòêè ïðè íà÷àëíè êîíöåíòðà- ticle synthesized by the sol-precipitation process. Ce- öèè íà àäñîðáòèâà 275 è 550 mg/L. Òåçè ñòîé- ramics International 35:1015-1019. íîñòè ñà ïîäáðàíè âúç îñíîâà íà ïîâåäåíèåòî íà [23] Han Y., Taylor A., Mantle M., Knowles K. 2007. ñâîáîäíèòå êëåòêè, èëþñòðèðàíî ÷ðåç àäñîðáöèîí- Sol-gel-derived organic-inorganic hybrid materials. J íàòà èçîòåðìà. Êèíåòè÷íî óðàâíåíèå îò ïñåâäî- Non-Crystalline Solids 353:313-320. âòîðè ïîðÿäúê å èçïîëçâàíî çà îïèñàíèå íà îïèò- [24] Vinogradova E., Estrada M., Moreno A. 2006. íèòå äàííè. Óñòàíîâåíè ñà ïî-âèñîêè ñòîéíîñòè çà Colloidal aggregation phenomena: Spatial structuring êîíöåíòðàöèÿòà íà àäñîðáàòà ïðè èìîáèëèçèðàíè of TEOS-derived silica aerogels. J Colloid Interface Sci êëåòêè è ïðè ïî-âèñîêî ñúäúðæàíèå íà õèäðîêñè- 298:209-212. ïðîïèë öåëóëîçà â ìàòðèöèòå, èçïîëçâàíè çà èìî- áèëèçàöèÿ.
INVERSE FIELD SOURCE PROBLEMS IN BIOMAGNETICS
Iliana Marinova1, Valentin Mateev1, Àna Chakarova2 1Technical University of Sofia, Department of Electrical Apparatus 8, Kliment Ohridski Blvd., 1756 Sofia, Bulgaria 2National Specialized Hospital for Active Treatment of Oncology, Department of Radiotherapy 6, Plovdivsko pole Str., 1756 Sofia, Bulgaria Abstract cantly improved by new highly precise computa- Electromagnetic field distribution in biological tional models and field reconstruction strategies. structures is challenging multidisciplinary problem These problems can be broadly divided into two which may offer many new opportunities for main topics. First is the field of biomagnetic or medical diagnosis and therapy due to modern sci- bioelectric fields produced naturally into the bio- entific approaches. Investigation of electromag- logical structures. Second wide topic contains all netic fields, processes and phenomena is signifi- problems of interaction of outer electromagnetic
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Modeling of electromagnetic field distribu- to the complicated structure of the human body, tions in biological objects must be handled by consisting of organs with varying dimensions and modern numerical method covering all specific geometrically complicated shapes, all exhibiting anatomical properties of modeled application. different electrical properties, the major task Finite element method (FEM) is a powerful nu- from the simulations point of view is to achieve merical method capable to solve such complex a very fine spatial resolution in the computations. problems taking into account all characteristics Developed for computations 3D human model, and special features. Recent achievements of the containing all major anatomical systems and or- FEM give possibilities to model fully three-dimen- gans is presented in Fig. 2. sional, nonlinear, inhomogeneous, or anisotropy For computer modeling of electromagnetic multi-tissue, and multi-joint systems of biological fields distributions in human body the electro- structures. magnetic properties of live tissue have to be in- In this paper some new approaches and re- corporated into 3D geometrical models of hu- sults in determination of biomagnetic fields and man organs. The specific electromagnetic mate- biomagnetic interaction are presented. These re- rial properties are introduced for each tissue of searches are focused exclusively in the area of the developed model. Properties of tumor and inverse source and material properties recon- other specific tissues which may have great dis- struction in inaccessible for direct measurements persion due to many individual characteristics are regions. Results from computational techniques of special interest. These electromagnetic prop- are presented and discussed. erties are accurately measured and determinate for investigated cases [6-8].
Fig. 2. 3D human anatomy model with some of included organs and subsystems
3D HUMAN ANATOMY MODEL INVERSE SOURCE RECONSTRUCTION In order to achieve accurate field distribution PROBLEM FOR MCG results the realistic 3D geometry vector models Measurement of biologically produced mag- are developed. The data from modern medical netic fields was unknown before the invention imaging techniques, such as CT and MRI have of SQUIDs. This is because the fields in question been used for building of a precise three-dimen- are of such a small value, typically 1nT to less sional high-resolution anatomical model of the than 1pT. There are many magnetic fields which human body [4]. Recently, different techniques have been measured, ranging from the suscepti- have been utilized to convert automatically 3D bility of tissue to applied magnetic fields to ionic image data into 3D FEM models or into numeri- healing currents and those associated with neu- cal meshes suitable for FEM analysis [4-5]. Due ral or muscle activity. [9]
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MCG utilizes SQUIDs to measure the mag- netic fields produced in the heart by ionic current (1) flow arising from cardiac muscle contractions. Current MCG techniques have spatial resolutions (2) of 1-5mm but the time resolution is between 1- 5ms allowing real time imaging. The main prob- where G is 3D Greens function given by lem comes from the actual computing of the equation (3) current density. For every magnetic field re- corded there is infinite number of current densi- (3) ties that would give rise to such a field. Heart is where is the distance radius-vector between considered to be a much simpler shape which r coordinates of each measurement mesh nodes contains current sources. Actually heart volume and current source nodes, is investigated as magnetically homogenous, fine structure mesh where current sources or electric (4) dipoles are searched. A solution is then com- puted fitting certain boundary conditions (such where are coordinates of each as distribution having the least energy). In spite measurement mesh node; of these simplifications, an accurate current dis- are coordinates of current source tribution can be obtained. Here fast inverse approach for reconstruction nodes. of current sources by locally measured magnetic In order to realize the reconstruction ap- field data is presented. Results for reconstructed proach the whole body domain Ù is divided in el- current dipoles for heart volume according to ementary volumes . The magnetic the measured surface data are presented in Fig. field distribution is measured in n points over the 3-a-c. The magnetic field distributions were chest surface, Fig. 3. measured using SQUID biomagnetometer system For determination of field sources distribution containing 31 magnetic sensors. Complete SQUID (2) is transformed in system of linear equations (5). data set is presented at [9].
(a) Measured magnetic (b) reconstructed (c) voltage flux density data current densities distribution Fig. 3. Measured magnetic flux density, z-direction in chest region, reconstructed current density vectors in heart layer and corresponding voltage distribution in heart layer
The developed approach is suitable for cur- rent source distribution reconstruction in mag- (5) , netically homogenous, linear non-magnetic media ( ). Solution of (1) for magnetic vector where Y is the vector with measured values presented by (6) and (7). potential A is expressed by (2) Yi (6) ,
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(11) , (7) ,
where is given by equation (8) where B is magnetic flux density, , µ xj is magnetic permeability, is magnetic field in- (8) . H tensity. In elementary domain a constant current dV According to and introducing mag- density value is used X =const. sj netic vector potential by from (11) is determined with equation (9) by Greens A ci function for and . is obtained Gij i=1,...,n j=1,...,m
(9) . (12) . Finally is given by equation (10). ci
Using electric scalar potential Vå, (12) can also (10) , be expressed as
where (13) . is the normal direction vector with direction nj of ; The induced current density J satisfies the xsj e - direction vector between current source j Ohms law is eij - point to field measurements i - point; - radius vector between current source j - (14) . rij point to field measurements i - point. According to Ampere law can be written (15) . Accurate 3D images of the reconstructed current density within used initial data are pre- sented in Fig. 3. The magnetic field distributions The governing equation for magnetic vector were measured using SQUID biomagnetometer potential-electric scalar potential (A-V, A) formu- system containing 31 magnetic sensors [9]. Mag- lation is netic field flux density is measured in a moment of the T-wave. Current density vectors are re- constructed in a structural mesh of 10x10 nodes, (16) . with spacing 10mm, which presents a 2D quad- Three-dimensional harmonic and transient ratic plane in heart region, Fig. 3-b. electromagnetic problems with Zero value MODELING OF MRI GRADIENT FIELD IN- Dirichlet boundary condition for the free space TERACTION WITH THE HUMAN BODY boundary according FEM formulation are utilized Effects of low-frequency electromagnetic for the field analysis in human tissues. fields encountered specifically during MRI are The induced currents in tissue are expressed examined. The primary biological effect at typi- by (14). cal switching gradient frequency of 1kHz is non- Heating effect on the tissue can be calculated thermal peripheral nerve stimulation. These ef- with Joule heating Q. fects are successfully simulated with 3D human model. [10-11] (17) , Electromagnetic field distribution inside the where ñ=1/ó, is specific electrical resistance. conductive tissue region depends on the time Open magnetic circuit MRI system shown on varying magnetic flux density. The activation Fig.4 is investigated. A three-dimensional har- source is the electric field E induced in the tissues monic and transient magnetic problem according and expressed by using Faradays law FEM for magnetic vector potential-electric scalar
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National Scientific Programmes with European Dimensions
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(a) Open MRI system (b) Coil system Fig. 4. Open magnetic circuit of investigated MRI system main with correcting and gradient coils
(a) MVP - real part (b) MVP - imaginary part Fig. 5. Magnetic vector potential (MVP) distribution in 3D human model
(a) Magnetic flux density - real part (b) Magnetic flux density - imaginary part Fig. 6. Magnetic flux density distribution in 3D human model
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(a) Scalar electric potential - real part (b) Scalar electric potential - imaginary part Fig. 7. Scalar electric potential distribution in 3D human model
Fig. 8. Induced current density distribution in 3D human model
ELECTRIC ABLATION (17) , Electric ablation is used to destroy pathologic tissue by heating of the targeted tissue with di- where ó is specific electric conductivity, å - per- rectly applied electric current. For tumor treat- mittivity of investigated tissues. ments the electrical ablation is currently the The electric field E is determined by (18) most commonly used thermal ablation therapy (18) . applied in a clinical setting. Cryoablation, which is FEM is applied for analysis of electric field. another fairly common tumor ablation modality, Field sources are pair of electrodes, operating uses freezing instead of heat to kill tissue [12]. at constant frequency of 500kHz with rms volt- Current studies suggest that electrical ablation is age of 10kV. much better than chemotherapy alone [13]. Thermal field modeling Radiofrequency ablation and microwave ablation The thermal field at steady-state is governed are clinically used for minimally invasive treat- by the Poissons equation with respect to the ment of inoperable tumors of liver, as well as temperature T other organs such as lung, kidney and bone [14]. (19) , We develop a model for investigation of where Q is the heat source defined by elec- tumor liver ablation. The tissue regions and elec- tric field, i.e., by the solution of the electric field tromagnetic characteristics are determined and problem; incorporated in the model. The tissues are di- ë is the thermal conductivity. rectly heated by electrical ablation device and Heat source density Q defined by (20), the thermal conduction of tissues is dominating in the thermal process. The model is designed to (20) . use common properties of ablation devices cur- Coupled field problem rently applied in clinical practice. For tumor temperature determination a first- Electric field modeling order coupling between two field models (elec- The governing equation for electric field dis- tric and thermal) is made. The coupling of the tributions is the Laplace equation Eqn. 1 [5] with two fields is in one direction. The heat source respect to electric scalar potential V, depends on the results of the electric field
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National Scientific Programmes with European Dimensions
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Fig. 9. Architecture of the couple field problem solution
(a) 3D model (b) electric scalar potential (c) inside electric field (d) temperature distribution Fig. 10. Electric ablation model results: 3D model, electric scalar potential distribution in surface and cross-section area, temperature overheating distribution in liver and tumor area.
Results from coupled field modeling process Proposed applications, forward and inverse are presented in Fig.10. Electric scalar potential problems for them are very suitable for deter- distribution in 3D model surface is shown in mination of energy interaction optimization be- Fig.10-(b). Electric scalar potential distribution in tween biological structures and electromagnetic 3D model cross-section is shown in Fig.10-(c). devices which will be determined at different Treated tumor is a complexly shaped object with conditions and modes. maximal size of about 10-15mm. Final tempera- Three-dimensional adequate mathematical ture distribution in liver region is shown in Fig.10- models taking into account all essential features (d), where the treated tumor is heated to nearly of the processes at corresponding modes of 40° C above body temperature. Thermal impact electromagnetic device operation as well as me- in tissue between electrodes outside tumor vol- dia parameters of biological structure give possi- ume may also be observed in the top side of bility for factor and condition influence study liver. This negative effect must be minimized for over these fields, processes and phenomena. good electrical ablation treatment planning. Op- Quantitative results for electromagnetic and timal individual therapy strategy could be organ- thermal field distribution in inner organs can be ized including this kind of field modeling proce- easily made. Complete procedure of electromag- dure. netic field model building is applicable for device
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and process optimization due to a desired elec- Vol. 66, pp. 1075-1079. [9] Brauer, H., Ziolkowski, M., Haueisen, J., TEAM tromagnetic or corresponding thermal impact workshop problem 31: Reconstruction of Low Fre- over a known object. quency Currents Using Minimum Norm Least Squares Proposed approaches are envisaged to be on a Planar Surface. COMPUMAG 2001, Evian, Proc. developed on the base of the three-dimensional TEAM Workshop, pp. 66-67. [10] Glover, P., Interaction of MRI field gradients with models with application of up-to-date methods the human body, Phys. Med. Biol. 54, 2009, pp.99-115. and technologies in the area of numerical meth- [11] International Electrotechnical Commission. In- ods, signal and image processing, optimization, ternational standard: part 2. Particular requirements for the safety of magnetic resonance equipment for image reconstructions and visualization. The medical diagnosis. CEI/IEC 601-2-33. Geneve, Suisse: models developed could be applied for solving International Electrotechnical Commission; 1995. other problems in different scientific areas. The [12] Schramm1, W., Yang, D., Wood, B., Rattay, F., and Haemmerich, D., Contribution of Direct Heating, Ther- models and approaches must be generalized in mal Conduction and Perfusion during Radiofrequency theoretical aspect for solution of forward and and Microwave Ablation. The Open Biomedical Engi- inverse problems in electromagnetism and neering Journal, 2007, 1, pp. 47-52. bioelectromagnetism. [13] Livraghi, T., Mueller, P., Silverman, S., van Sonnenberg, E., McMullen, W., Solbiati, L., Editors. Tumor Acknowledgment Ablation: Principles and Practice. Springer, 2005. We wish to thank Prof. Jens Haueisen from [14] Mir, L. M., Orlowski, S. Mechanisms of electro- Technical University Ilmenau for providing MCG chemotheraphy. Advanced Drug Delivery Reviews, 35, 1999, pp. 107-118. data set used in this article. This research is supported by the National ÎÁÐÀÒÍÈ ÅËÅÊÒÐÎÌÀÃÍÈÒÍÈ ÇÀÄÀ×È Â Science Fund of the Ministry of Education and ÁÈÎÅËÅÊÒÐÎÌÀÃÍÅÒÈÇÌÀ Science under Contract D002-157/2008. Èëèàíà Ìàðèíîâà1, Âàëåíòèí Ìàòååâ1, 2 References Àíà ×àêúðîâà 1Òåõíè÷åñêè óíèâåðñèòåò - Ñîôèÿ, Êàòåäðà [1] Malmivuo J., R. Plonsey. Bioelectromagnetism, Eëåêòðè÷åñêè àïàðàòè Principles and Applications of Bioelectric and áóë. Êëèìåíò Îõðèäñêè ¹8, 1756 Ñîôèÿ Biomagnetic Fields. Oxford University Press, New York, 2Íàöèîíàëíà ñïåöèàëèçèðàíà áîëíèöà çà 1995. àêòèâíî ëå÷åíèå íà îíêîëîãè÷íè çàáîëÿâàíèÿ, [2] Ueno S., Biological effects of magnetic and Îòäåëåíèå ïî ðàäèîòåðàïèÿ electromagnetic fields. Plenum press, New York, 1996. óë. Ïëîâäèâñêî ïîëå ¹6, 1756 Ñîôèÿ [3] Marinova I., V. Mateev, I. Yatchev, L. Kuncheva, A. Chakarova. Optimization of Energy Interaction be- Ðåçþìå tween Biological Structures and Electromagnetic De- Îïðåäåëÿíåòî íà åëåêòðîìàãíèòíîòî ïîëå â vices. Advances in Bulgarian Science (ABS), Journal of áèîëîãè÷íèòå îáåêòè å âàæíà èíòåðäèñöèïëèíàðíà National Center for Information and Documentation çàäà÷à, ðåøàâàíåòî íà êîÿòî ìîæå äà ïðåäëîæè (NACID), Sofia, No.3, 2009, pp. 7-15. ìíîãî íîâè âúçìîæíîñòè çà ìåäèöèíñêà äèàãíîñ- [4] Zachow S., M. Zilske, H-C. Hege. 3D Reconstruc- òèêà è òåðàïèÿ áëàãîäàðåíèå íà ðàçðàáîòåíèòå tion of Individual Anatomy from Medical Image Data: íîâè ìåòîäè è ñðåäñòâà. Èçãðàæäàíåòî íà íîâè Segmentation and Geometry Proceedings of the 25th ïðåöèçíè èç÷èñëèòåëíè ìîäåëè è ïîäõîäè çà îá- CADFEM Users Meeting 2007, Congress Center Dres- ðàòíà ðåêîíñòðóêöèÿ íà ïîëåòà äàâàò âúçìîæíîñò den, Germany, November 21-23, 2007. çà èçñëåäâàíå íà ïîëåòà è ïðîöåñè ñ âèñîêà òî÷- [5] ANSYS Release 12.0 Documentation, 2009. íîñò. Òåçè çàäà÷è ìîãàò äà áúäàò ðàçäåëåíè íà äâà [6] Marinova I., V. Mateev, H. Endo, Y. Saito. îñíîâíè êëàñà. Ïúðâèÿò å îáëàñòòà áèîìàãíèòíèòå Modeling and Measurement System for Magnetic èëè áèîåëåêòðè÷åñêèòå ïîëåòà åñòåñòâåíî ñúçäàäå- Field Distributions in Biological Structures. Interna- íè â áèîëîãè÷íèòå îáåêòè. Âòîðèÿò îáøèðåí êëàñ tional Journal on Smart Sensing and Intelligent Sys- îáõâàùà âñè÷êè çàäà÷è íà âçàèìîäåéñòâèå íà áè- tems, Vol. 2, No. 2, June 2009, pp. 262-278. îëîãè÷íèòå îáåêòè ñ âúíøíè åëåêòðîìàãíèòíè [7] Marinova I., V. Mateev. Electromagnetic fields ïîëåòà.  ñòàòèÿòà ñà ïðåäñòàâåíè íÿêîè íîâè in human tissue. Proceedings of International Confer- ïîäõîäè è ðåçóëòàòè â èçñëåäâàíåòî íà åëåêòðî- ence on Computer, Electrical, and Systems Science, and ìàãíèòíîòî ïîëå â áèîëîãè÷íè îáåêòè. Òåçè èç- Engineering, 28-30 April, Rome, Italy, 2010, Vol. 64, pp. ñëåäâàíèÿ ñà ñúñðåäîòî÷åíè ïðåäèìíî â îáëàñòòà 196-201. íà îáðàòíèòå çàäà÷è çà îïðåäåëÿíå íà èçòî÷íèöè, [8] Marinova I., V. Mateev. Determination of Elec- ñâîéñòâà è ðàçïðåäåëåíèÿ íà åëåêòðîìàãíèòíè ïî- tromagnetic Properties of Human Tissues, Proceedings ëåòà â íåäîñòúïíè çà äèðåêòíî èçìåðâàíå îáëàñòè. of International Conference on Computational and Ïðåäñòàâåíè è äèñêóòèðàíè ñà ðåçóëòàòè îò Applied Mathematics, 28-30 June, Paris, France, 2010, ðàçãëåäàíèòå èç÷èñëèòåëíè ìåòîäè.
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AN INTEGRAL SOLUTION FOR TELEMEDICINE AND HOSPITAL INFORMATION SYSTEM
Ivan Evg. Ivanov, Vesselin Gueorguiev Technical University - Sofia 8, Kliment Ohridski Blvd., 1797 Sofia, Bulgaria E-mails: [email protected]; [email protected]
Abstract rectly to computer application with HMI. The aim of this paper is to present results Data are distributed, heterogeneous and obtained in the context of joint research with changeable- Hospital medical systems collect a Medical University Sofia about investigations, de- diverse variety of patient information repre- sign, organisation and future expansion of a hos- sented in many digitized or hard-written types. pital information system. This research is in the Creation and support of patients analyses li- area of e-Health and Telehealth and is oriented brary is a problem solved under presented to complex investigation of new concepts and project. methods for continuous acquisition of patients Data validity, security and protection - Data vital data, transmission, collection and binding of validity is very important to make decision-mak- that data for diagnostic and disease tracking ing process stable and safe. This includes time purposes as well as investigations on relevance validity and safety and security of delivery. Data of life quality and healthcare based on the e- access and privacy are very important and have Health technologies. to provide end-to-end security and validation in the system. INTRODUCTION Tracking patients when they are out of the The aim of this paper is to present results hospital - technical, medical and economical as- obtained in the context of the Medical data pect. acquisition, processing and collection for e-health IT problems of a) archiving and b) solutions joint research project for investigation, digitalisation of paper-based video-images. design, organisation and future expansion of a Improvement of analyses of medical video- hospital information system [1]. images. The research started with deep investigation Of course, this list cannot pretend to cover all of current status of hospital information sys- possible aspect of hospital information systems, tems on the territory of the Medical University solutions, problems and similar. The structure of Sofia and implementation of a pilot version of implemented intelligent hospital information sys- integrated solution. Elimination of the usual pa- tem is presented briefly at the end of this mate- per-based information exchange to e-health and rial. IT-based one is one of the major project topics. INTEGRATION OF AVAILABLE MEDICAL Medical University Sofia is a huge hospital APPARATUS AND SOFTWARE SYSTEMS IN complex situated on a large territory and has NEW SYSTEM tens of different clinics, laboratories and build- Starting with the investigation of how to in- ings. tegrate available equipment in one system we Results of this investigation and some of im- contacted directly vendors representatives for plemented solutions are discussed hereafter. We detailed technical data. The equipment includes focused on the following main problems: from very modern to 10-15 years old machines. Interface incompatibility between different Interfaces to humans and to other computers medical systems and apparatus - Medical sys- vary much. Computer interfaces include RS232 / tems from different vendors are incompatible. RS485 and Ethernet wired connections, floppy- Most of them are designed to transfer data di- disk data exchange and on-screen or printed
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output. Protocols are very different, too. All this wearable biosensors available on the market are stands as big challenge to the integration team. 1 or 3 lead ECG sensors, spirometers, pulse and We contacted technical groups supporting other blood pressure meters, thermometers, SPO2 me- hospitals and found that even products from ters and glucometers. All of these sensors were one and the same vendor are not fully compat- investigated [7]. ible on interface and protocol levels. As an ex- Three to two years ago these devices had ample DICOM-based image systems can be mainly a wired connection to a computer. Their shown. DICOM has variety of dialects and needs weight was not negligible, either. Today these additional processing to make all sources fully types of devices are greatly improved. They have compatible with all visualisation systems. WiFi or Bluetooth wireless communication capa- Data integration bilities. The weight is tens of grams. Power con- A hospital medical system collects a variety sumption is also much reduced. All this is a basis of patient information represented in many dig- for increasing the remote acquisition of human ital or hand-written types. All over the world, a vital data and doing some in situ pre-diagnostics huge number of standards of organisation and or pre-analysis. representation of the Electronic Health Record Basic structure of a remote data acquisi- exist (HER) [2, 3]. Unfortunately, many of them tion node depend on local law regulations and even in Eu- ropean Community they are not synchronised. Hospital data (not originally included in HER) are harder to track - they include information from many sources - diagnoses, many types of labo- ratory results, imaging results - X-ray / ultra- sound / scanners / Doppler, medications, consul- tations. These data are very distributed. In a large hospital like the Medical University Sofia original data are held on the laboratories and clinics Fig. 1. Typical structure of a vital data acquisi- servers. They have to be exchanged and bound tion node based on a smart phone in patients records. Such a database did not ex- ist before the beginning of this project. One of Today smart phones are equipped with the biggest problems was the fact that data are Bluetooth and/or WiFi communications. Depend- very changeable, the amount increased all the ing on the software platform and operating sys- time and the structure depends on uncontrolla- tem they can execute Java applets and/or C/C# ble variety of external (mostly human) factors. applications. Devices provided by different ven- Today, an information system based on unified dors support different communication protocols. generalised structure which covers all types of This requests the installation of additional com- available data is implemented in the MU Sofia munication drivers on the phone (over Bluetooth medical information system [4, 6]. or WiFi). The most common versions are based Tracking patients when they are out of on Bluetooth communication. Depending on the the hospital drivers not every sensor can be connected to One big objective of the presented project every smart phone. was to implement tracking patients when they Many providers offer closed multi-layer sys- finish the hospital phase of medication. Experi- tems which does not allow their sensors to be mentation field was clinic of pulmonary diseases. used with other systems and also excludes the Technological idea was to equip patients with possibility to extend the system with other sen- mobile sensors controllable via smart phones sors. When such providers do not offer a full list and to collect and transmit data using SMS and/ of sensors, remote patient support becomes lim- or data channels. Currently in the non-military ited to the available peripherals. areas of application the most common mobile/ Another problem is that some data acquisition
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○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ drivers are very aggressive and start to connect possibility to extend the system with other sen- and transmit acquired data to the upper system sors. When such providers do not offer a full list levels without user permission. This increases the of sensors, remote patient support becomes lim- exploitation price and lowers battery life. ited to the available peripherals. Fortunately today providers are starting to Another problem is that some data acquisi- sell their sensors with open source libraries or li- tion software for smart phones is very aggres- braries of modules configurable by the customer sive and starts to connect and transmit acquired (or IT personnel). We studied families of sensors data to the upper system levels without user provided by Intelesens Ltd., Medic4All, THOR permission. This increases the exploitation price Medical systems, Card Guard, Aerotel and AIT and lowers battery life. GmbH. Uninterrupted usage of any type of sensor A typical structure of a remote data acquisi- is impossible. Phones battery cannot last more tion node based on smart phone is shown on than 6 hours on intensive Bluetooth or WiFi com- Fig.1. It includes the most common available to- munication. Investigation oriented to sports con- day sensors for vital data. trol envisaged that this technology can be used Depending on the functionality of the sensors only for approximately short training processes. data can be received on demand or continuously Performance analysis of the computational (sessions with unlimited time length). power targeted smart phones envisaged that in Modern mobile phones have large memories case of ordinary load we can conclude that the and can save very big amounts of acquired data smart phones studied can run in real-time many autonomously. This reduces the need for perma- on-site analyses. nent connection to the hospital servers. Conclusions about medical and economical Typical layered system is shown on Fig. 2. aspects: Figure 2 presents a new element - a data From the very beginning of experiments, supervising medical doctors concluded that this remote control over their patients data helped them to prevent possible dangerous situations but this needs a lot of human effort. A system to control vital parameters is needed. It cannot be simple in/out of boundary control but com- plicated multi-variable decision-making system. Presently, some work is in progress but it still needs a lot of investigations. Instructions to patients about interpreting very simple raw data from sensors decreased number of hospital visits based on apprehen- Fig. 2. Layered structure of a vital data acqui- sions. Psychologically, patients felt much com- sition system fortable when they knew somebody keeps an eye on them. Thus hospital expenses were de- analysis module. Additionally a bi-directional con- creased. nection to the upper system layers provides the One important remark is that because of fi- possibilities to send commands to the phone- nancial limitations, the number of obtained sen- based system and to enhance the quality of sors is relatively low and the investigation was data acquisition. useful for experimental conclusions and future The following are our conclusions about tech- directions but is not enough representative for nical aspects: statistical purposes. Many providers offer closed multi-layer sys- DATA VALIDITY, SECURITY AND PROTEC- tems which does not allow their sensors to be TION used with other systems and also excludes the Developing and implementing hospital infor-
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mation systems including remote data acquisition film grain. This system is equipped with software requires strong data protection. But before this, for images post-processing. Some results are some other problems important for the patients presented in [8]. have to be resolved. First is data validity. Investi- A very important additional problem is the gating paper-based process we found that in size of a digital archive. For medium level Bulgar- many cases information is wrong or interpreted ian hospital (covering 30000-50000 people) inadequately or simply lost somewhere in docu- only DICOM library is more than 5-6 Tbs/year. ment paths. This is a well-known administrative Today, disk devices have huge capacities but nev- problem but here it is important because human ertheless increasing hospital data server with health depends on it. 10TB/year is problematic. Where the biggest problems are: A major problem of diagnosis methods based Remote data acquisition via smart phones on X-ray images is images quality. This applies to needs data validation and time stampings. Be- all diseases where one of the following changes cause sensors are worn by patients and acquisi- in image can be observed: changes with a small tion and communication software is run by them X-ray density, the appearance of shadows in the too, improper measurements and operations are image, soft shadows, structural formations with a common. certain shape (linear, circular or otherwise), etc. Inter-hospital data exchange is not always Pulmonary diseases are targeted here because in marked properly. Results for one patient can be many cases X-ray image is the only way to diag- assigned to other. This is a usual human error - nose in time diseases like peripheral lung cancer, to mark a box near the exact one or to change secondary tuberculosis, pulmonary embolism, some letter or digit. bronchiectasis, echinococcus of the lung, etc. The On the one hand, medical doctors are over- low quality of X-ray images is one of the reasons loaded and normally hate to go through deep for hypo- or hyper-diagnosis as a result of incor- and strong security system. From patients side, rect deciphering. This problem is even more pro- data protection and security are very important. nounced using the old type X-ray images (ana- These opposite restrictions make solutions hard log images). New digital X-ray machines do not to design. Currently, we think that only hardware increase the main quality of images. They are identification systems fast enough and easy to only faster and the image is better measurable. use can solve identification problems and access Digitalisation of medical images is a very hard rights, but even this opens a new domain of task. Our target was perception improvement of problems. processed X-ray images under elimination medi- Digitalisation of film and paper archives cal artifact: only after eliminating the possibility Designing the solution for integrated hospital of the occurrence of medical artifacts developed information system required us to think how to techniques and methods can be used for the transfer current archives in a digital form. Of purposes of computer-assisted diagnostics. The course, the problem for archive digitalisation has difference between human eyes and digital cam- existed for more than 20 years. The main prob- eras as a vision device is due mostly to different lem we had to solve was digitalisation of video color spaces and the specific properties of hu- imaging library. Investigation about possibilities man vision known as visual weight and ap- to digitise images of different types envisaged proximate color consistence [8]. As a result in that the on-hand solution to use flat-bed scan- many cases when human percepts X-rays as ners is not applicable. Available scanners for grayscale images, digital cameras produce color large X-ray pictures start from 15000 USD. Serv- image. In all these cases a conversion color-to- ices for film scanning are from 2 to 10 USD de- grayscale is needed. This is risky because meth- pending on picture and requirements. Financial ods for this conversion can produce artifacts and limitations directed us to design low-cost scan- some of them can be characterized as medical ners for all kinds of films and pictures. Their artifacts [9]. price is much lower and resolution is better than To improve the quality of the digitalized X-
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Now bandwidth of 1GB is possible and this guar- for all patients; fast access to disease history antees on-line diagnostics and data exchange and hospital archive. between sources, doctors terminals and storage Data analyses server servers. This is the core for future advances. Data Clinics server mining services will be positioned there. A hospi- It controls access over the local network, da- tal grid with specialised servers will be built on tabase consistency and tracks patients at home this basis. care. Fixed hospital network Acknowledgement Fixed clinical network provides connectivity This work is started and partially funded by for all machines and apparatus in the hospital Bulgarian NSF under D002/113-2008 and DRNF from one side and servers and personnels ter- 02/3-2009 projects.
Fig. 6. General structure of IHIS
minals from the other side. Additionally it guar- References antees better redundancy and offers possibility [1] Ivan E. Ivanov, Vesselin E. Gueorguiev. Medi- to control internal clinical networks loading. cal data acquisition, processing and collection for e Wireless medical sensor network health solutions - DAPSEpro, The International eHealth, Telemedicine and Health ICT Forum2008, Luxemburg, This network enables access for the medical April, 2008 personnel to data servers. Additionally, sensors [2] www.hl7.org and apparatus generating small amount of data [3] www.OpenEHR.org can be mobile on hospital territory. This guaran- [4] Ivan. E. Ivanov, V. Gueorguiev, V. Bodurski, E. Markov. Electronic Health Record: The State of The tees unbroken control when patients can carry Art, Computer Science2009, 05 - 06 November 2009, their vital data acquisition sensors or simply to Sofia, Bulgaria move patients over clinics without loss of con- [5] Ivan E. Ivanov, V. Gueorguiev, N. Balgzhiev, B. Kehayov. Software Architecture For Medical Informa- nectivity. tion Systems, Computer Science2009, 05 - 06 Novem- Management server ber 2009, Sofia, Bulgaria It controls all administrative processes, hosts [6] Nakov O., V. Gueorguiev, I. E. Ivanov, V. Trifonov. Methadata organization in Electronic Health all records about manipulations (total and asso- Record (in Bulgarian), Computer Engineering, 2, 2009 ciated to every patient), personnel and patients [7] Ivan Evg. Ivanov, Vesselin Gueorguiev, Velizar archive, etc. Based on this, doctors can do differ- Bodurski, Vencislav Trifonov. Telemedicine and Smart ent analyses and increase quality of medication. Phones as Medical Peripheral Devices (Computational Approaches), DESE 2010, London, UK, September 2010 Main database server [8] Vesselin E. Gueorguiev, Ivan E. Ivanov, The SAN network offers: on-line information Dessislava Georgieva. Digital Cameras as Low-cost
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Tools for Telemedicine and e-Health: Opportunities and Constraints, HEALTHINF 2011, Rome, Italy, January 2011 [9] M. Èadík, Perceptual evaluation of color-to- grayscale image conversions. Computer Graphics Fo- rum, vol. 27(7), pp.1745-1754, 2008.
ÈÍÒÅÃÐÈÐÀÍÎ ÐÅØÅÍÈÅ ÇÀ ÎÁÅÄÈÍÅÍÈÅ ÍÀ ÁÎËÍÈ×ÍÀ ÈÍÔÎÐÌÀÖÈÎÍÍÀ ÑÈÑÒÅÌÀ È ÒÅËÅÌÅÄÈÖÈÍÑÊÈ ÒÅÕÍÎËÎÃÈÈ
Èâàí Åâã. Èâàíîâ, Âåñåëèí Ãåîðãèåâ Òåõíè÷åñêè óíèâåðñèòåò - Ñîôèÿ Áóë. Êëèìåíò Îõðèäñêè ¹ 8, 1797 Ñîôèÿ
Ðåçþìå Ñòàòèÿòà ðàçãëåæäà ðåçóëòàòèòå, ïîëó÷åíè â ðàìêèòå íà ñúâìåñòåí ïðîåêò ìåæäó Òåõíè÷åñêè óíèâåðñèòåò - Ñîôèÿ è Ìåäèöèíñêè óíèâåðñèòåò - Ñîôèÿ. Ðàçãëåæäàò ñå íà÷àëíèòå ïðîó÷âàíèÿ, äè- çàéíà, îðãàíèçàöèÿòà è áúäåùîòî ðàçâèòèå íà áîë- íè÷íà èíôîðìàöèîííà ñèñòåìà. Òîâà ïðîó÷âàíå å â îáëàñòòà íà òåëåìåäèöèíàòà è íà åëåêòðîííîòî çäðàâåîïàçâàíå. Òî å îðèåíòèðàíî êúì øèðîêîìà- ùàáíî ïðîó÷âàíå íà íîâè êîíöåïöèè è ìåòîäè çà íåïðåêúñíàòî ñúáèðàíå íà äàííè çà æèçíåíèòå ïî- êàçàòåëè íà ïàöèåíòèòå, òÿõíîòî âàëèäèðàíå, ïðå- äàâàíå, îáðàáîòêà è ñúõðàíåíèå ñ äèàãíîñòè÷íè öåëè è çà ïðîñëåäÿâàíå íà çàáîëÿâàíèÿòà, êàêòî è çà ïðîó÷âàíå íà îòðàæåíèåòî íà íîâèòå åëåêòðîííè è èíôîðìàöèîííè òåõíîëîãèè âúðõó çäðàâåîïàç- àâàíåòî è ïîäîáðÿâàíåòî íà êà÷åñòâîòî íà æèâîò.
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BULGARIAN ADDED VALUE TO ERA
THE GENOMIC RESEARCH CENTER - A LONG STORY TOLD IN SHORT
Ivan Minkov Plovdiv University Paisii Hilendarski, Faculty of Biology 24, Tzar Assen Str., 4000 Plovdiv, Bulgaria
It is the idea what matters. If you want to of people in diverse research areas of Molecular accomplish something, you need a good idea. Biology. Also, we tried to select good quality re- Everything else is secondary. The University of searchers and only the most devoted survived. Plovdiv (UoP) has always been among the best After returning, people created their research Bulgarian universities. Nevertheless, Bulgarian sci- groups and this is how we founded the ence has long been centered in specialized re- Genomics Research Center (GRC) at the Faculty search centers, such as the Academy of Sciences of Biology, University of Plovdiv and recently a and the Agrarian Academy. This is one of the spin-off under the same name. largest gaps which should be filled in. This lack Times came when national financing started of collaboration between different groups and to rise, we participated in several EU programs faculties, as well as the lack of interdisciplinary for University teaching enhancement (TEMPUS), studies constitute considerable problems. My research programs including NATO and Swiss childhood dream from years ago was to de- National Science Fund, but our main success was velop a high quality research infrastructure at our participation in a number of Framework Pro- the University, with which to compete with the gram projects for which the GRC got a Pythago- big players in the game. For the last 20 years, we ras award (2009) as a regional centre with the have perused the idea of developing research in highest Framework Programs 6 participation. In- the fields of Molecular Biology and especially evitably we came to understand that we needed Plant Molecular Biology and Biochemistry - labo- a really large project to strengthen the capacity ratories, equipment, but most importantly - hu- of the Center with which concentrate our stud- man potential. I was lucky enough to under- ies in a more focused area. Systems Biology, and stand that humans come first - you may have especially Genomics and Bioinformatics, seemed funds and equipment but without trained per- like the logical choice for a topic for the project. sonnel you would still not succeed. The main breakthrough came when the GRC re- This idea has to be developed in the condi- ceived serious financing from the Bulgarian Na- tions of severe funds restrictions. We have tional Science Fund, one of the projects being started almost from scratch - as a Department aimed at establishing a regional center for of Plant Physiology with 5-6 people, obsolete and genomics and bioinformatics. Unfortunately, the old-fashioned equipment and shabby laborato- Fund literally broke and the center was not ries mainly used for teaching with methods from established as planned. 50 years ago. We had no other option but to The EU program REGPOT was an ideal choice send our people all over Europe for training and to make the dream come true. After several dif- research. This primarily led to the specialization ficult and highly competitive submissions (three
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○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ years consequently, which in itself is another tion of having more research funds than ever thrilling story), we have finally succeeded in se- before. Even better, this is one of the most excit- curing a project with the acronym BioSUPPORT ing research areas in biology and for the most from this program with real financing to back it developed research entity - the GRC. With this up. Just as an universitys findings are useless if financing, we are doomed to further expand kept within a department, so specialists knowl- hoping that this project and our efforts will edge is ineffective if not brought into a wider have a sustainable future. To secure this future, picture. In keeping with this thought, BioSUPPORT we hope to be able to establishing a Technology emphasizes that collaborative knowledge is a key Centre with the help of the Structural Funds, as in the future of the GRC and stresses that their well as a Technology Park with the help of in- biggest goal is to foster the integration of the dustry investment, with both structures compris- University into the wider stage of European re- ing almost the same researchers involved in search. The variety of successful and worthy BioSUPPORT. We hope that the Cooperative Pro- projects currently being conducted at the Uni- gram from the FP7 and future Horizon 2020 will versity is a strong indication of the need to work provide additional funding. together. BioSUPPORT emphatically endorses this Some of the main goals of establishing the focus, aiming to extend it beyond the confines of GRC were to consolidate our researchers in UoP, the Faculty and highlight the importance of net- in addition to researchers from groups at Facul- working to provide a reinforced web of success. ties of Physics and Chemistry, as well as to find Such a collaborative spirit will not only develop a common basis for collaboration. In this way, I the reputation of University of Plovdiv interna- hope to help transform the University in a center tionally, but will also facilitate knowledge trans- of excellence in one specific scientific field. For fer, as well as advance the field greatly. the last 20 years, this has been the area of sys- Now, the situation at the GRC at the UoP is tems biology. Along with food biotechnology, rather complicated. At a time when many coun- these were the best developed areas at the Uni- tries and institutions are making cuts, the Univer- versity, distinguishing it from other large Bulgar- sity of Plovdiv and the GRC are focused on ex- ian universities. The main aim of the project is to pansion. This inevitably leads to difficulties in se- reinforce the research infrastructure and human curing the necessary funding and resources. The potential in those areas and to consolidate sci- current situation in Bulgaria is not much differ- ence in these fields of study. Ideally, the project ent from that of many other European coun- would turn the University in one of the best re- tries. Over the last three years, the national re- search institutions in national research and devel- search financing has been cut considerably. As opment. Another long-term goal is to overcome mentioned above, the Genomics Research Centre the gap between education and research at the has won seven large projects from the Bulgar- University, especially in the field of natural sci- ian National Science Fund (BNSF) and, together ences. with financing from the Framework Programs, Young researchers and PhD students benefit has started extensive development of research most from the project and the center. Significant infrastructure and human potential in the area part of the financing from the REGPOT project of molecular biology and bioinformatics. This is for mobility, giving young people opportunity success is a direct result of the long-lasting proc- to work in some of the best research institutions ess of human potential consolidation, from the in Europe. This allowed them to participate in Department of Plant Physiology of 1989 with projects not possible in UoP, the results of which just 5-6 researchers to the GRC of today with they could then publish in good peer review re- over 40 people. search papers and now the GRC has a good sci- Thanks to the largest ever financing from FP7 entific record. Infrastructure development also as the BioSUPPORT project and despite the sig- benefits young researchers by mitigating the nificant restructuring of the BNSF during this brain drain of Bulgarian scientists in recent years. time, the UoP now is in the rather exciting posi- This brain drain from the GRC in UoP has been
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much lower over the last 10 years and this is for groups at the University. Nevertheless some old several reasons - good research infrastructure, connections were strengthened and collabora- better project-based salaries, and good human tion was extended to other research groups and atmosphere. research areas. One example is the strengthen- Systems Biology comprises a broad range of ing of our collaboration with Mugla University, inter-disciplinary research areas in biology and Turkey from insect taxonomy to insect molecu- constitutes the application of dynamic systems lar biology and plant physiology, as well as the theory to the field of molecular biology. It cov- participation of other research groups. Collabo- ers Genomics, Metabolomics, Proteomics, ration with the University of Angers, France was Bioinformatics and a wide range of genetics in- expanded with additional connections to partici- vestigations which, when implemented in the pate in other FP7 projects, in addition to a new area of crop studies and biomedical problems, research group from UoP - the Faculty of Phys- represent clear societal benefits. To a great ex- ics, now included in this collaboration. Addition- tent, Biotechnology is an implementation of the ally, we have improved our collaboration with Systems Biology. The region of Plovdiv has al- Groningen University considerably and one of ways been famous for its agriculture, crops the post docs from this partner was employed breeding and food industry development. Con- with a contract to UoP. The University of sequently, the development of food biotechnolo- Potsdam also supports the GRC in the field of gies is directly relevant to regional problems and metabolomics and is training a person to take development. This is the reason we received sup- over the Metabolomics and Proteomics Lab at port from the municipality and the regional gov- UoP, as well. A much more intensive exchange ernors office during the project submission and was conducted with the University of Alicante, execution. This support, in the form of commu- Spain and as a result, Prof. Antonio Canals was nity land provided for our idea to organize a appointed Doctor Honoris Causa of University Technology Park in the field of agriculture and of Plovdiv. The John Innes Centre, U.K. are also biotechnologies show clearly that we address very active in their participation in establishing some important societal needs of the region. the Center, taking part in introducing a new re- The most important task left before search area at UoP - Plant Derived Vaccines, as BioSUPPORT is finished is the organization of well as taking part in other collaborative several new labs, the structuring for which projects. The idea to create an association be- started immediately after first project finished. tween the UoP and some small and medium Those are the Laboratories of Metabolomics and enterprises (SMEs) like Komihris Ltd., MultiCoats Proteomics, Confocal Microscopy, Next Genera- Ltd., Biovet JSC with an idea of Technology Cen- tion Sequencing and Atomic Force Microscopy. tre establishment has also been proposed. Gen- Part of it is finalizing equipment purchase organ- erally speaking, all previous liaisons are substan- ized during the first period of the project. An- tially intensified. other important task is the continuation of the mobility missions until the completion of the The established research GRC infrastructure project. Experienced researchers from UoP will already stands as a solid, internationally recog- also to attend several international congresses nized entity, as evident from the Molecular Ba- and conferences. One task which was rather sis of Plant Stress research conference in Bul- underestimated during the first period was dis- garia at the end of 2011. This conference (http:/ semination of the results of the project, but /cmbps.bio.uni-plovdiv.bg/), with the scientific more work will be done on the subject. An im- organizer Prof. Tsanko Gechev from the UoP- portant task towards the projects end is ensur- GRC, attracted more than 120 participants rep- ing of sustainability of the obtained results. resenting 23 countries and five continents. There, Most of our 21 European partners and sup- distinguished speakers, some of them ISI highly porters of the project for establishing the GRC cited (such as Pof. Klaus Apel from the Boyce were also previous contacts of different research Thomson Institute, Ithaca, USA, and the European
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The young researchers and PhD students from the GRC during one project workshop
Plant Science Organization president Prof. Plant Stress dedicated to the conference. This Heribert Hirt), together with high profile young issue will contain peer reviewed papers based on researchers with papers in Nature and Science some of the best contributions delivered at the (Prof. Christophe Laloi, Dr. Francesco Licausi, Dr. conference. Thus, the meeting was also a great Hiroaki Fujii) delivered exciting lectures on the success from a publication point of view, as well. latest developments in stress physiology and One of the main focuses of the project and plant development. A number of PhD students the developed GRC is the area of Bioinformatics. also contributed with lectures and posters, ensur- The focus of the Bioinformatics Lab (http:// ing a good balance between experience and bioinfo.uni-plovdiv.bg/) is on the development of youth. new methods, algorithms and computational From a scientific point of view, the conference software for exploring and interpreting genomic was a great success. Participants not only pre- data in a framework of automated sequence sented their results, but were also able to inter- analysis. Current emphasis is on the small RNAs act with each other, exchange ideas, and even dis- (microRNAs and small interfering RNAs) in cuss future collaborations and mutual projects. plants and animals. Activities include analysis of The quality of the keynote lecturers, as well as small RNA libraries from deep-sequencing data, the impressive number of universities and re- expression regulation profiling, novel miRNA search institutes, attracted sponsors such as gene discovery and annotation and their targets, Thermo Scientific, Monsanto, LemnaTech, Sigma- as well as identification of stress-related small Aldrich, Illumina, Carl Zeiss, LKB, BASF, Conviron, RNAs. The lab provides comprehensive models Evogene, Merck Millipore, as well as several Bul- and publicly available computational tools inte- garian companies. The international peer re- grating various levels of genomic data analysis viewed journal Cellular and Molecular Life Sci- of small RNAs. It also hosts several publicly avail- ences (Impact Factor 7.09) will publish a multi- able original bioinformatics tools and services: author review Molecular Basis of Plant Stress, MicroInspector software - a scanning soft- where most of the keynote speakers will contrib- ware for detection of miRNAs target sites; ute particular topics. In addition, the Oxford open starPRO DB - promoter siRNA target sites access journal Annals of Botany PLANTS will database; publish a special issue titled Molecular Basis of miRPlan/CLUSTER/DUPLEX software - de
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novo identification of plant miRNAs from deep- develop. Together with the recent development sequencing data. of an entire new laboratory from scratch, it cer- MirTour - discovery of plant miRNA tainly becomes clear that the department has homologs in EST/GSS datasets; collaborative development at its heart. Indeed, BrachyBrowse - Brachypodium siRNAs visual after two decades of research excellence, the browser database. GRC plays a key part in its industry and even The lab is also used in the computational bi- today the department is still making great strides, ology classes of BSc, MSc and PhD-student as constantly developing its facilities and its special- well as them with a specialized Linux computer ists. room, including HP ProLeant remote servers with Which are the main areas and laboratories pre-installed bioinformatics software packages. that comprise the GRC? Below I will explain the As an infrastructure hub, a network center main areas in recent science which GRC is ad- (NC) is established. This facilitates collaboration dressing now and will develop also in the near between different workgroups by providing future, as well as some of the challenges faced webpage hosting, project management and issue along the way. Consult the table at the end of tracking systems, mail groups, etc. The NC con- the article for a summary explanation. sists of high-performance servers placed in a Plant Breeding Technologies for Drought renovated server room. Resistance An important emphasis of the GRCs develop- Global climate change is predicted to increase ment is its connection with the industry. One of variability of water supply dramatically, both in the benefits from our strong cooperation with spatially and in time, and will thus affect the SMEs and the food industry is the ability to ap- growth of crops. Several European regions are ply for financing together. In our current situa- already at severe risk of drought, extreme tem- tion, direct benefit from the SMEs and the indus- peratures, and of other types of abiotic stress try is difficult. On the one hand, the current eco- linked to water (e.g. as a result of periodic nomic crisis makes companies hesitant to invest flooding or salt stress). This technology will ad- in science in general, and on the other, there dress water stress affecting crop plants and will arent very many big biotech companies in Bul- develop agricultural plant varieties better garia to begin with. One strategy available to us equipped to withstand it, enhancing the produc- is to strive for an association between the UoP tion of biomass and bioproducts. It will target and several SMEs - Komihris Ltd, MultiCoats LTD commercially important crops using state-of the- (participant in the project), GRC Ltd (spin-off art knowledge on molecular and genetic proc- SME). We can then apply for Structural Funds esses involved in plant tolerance and adaptation Call subsidies with which to establish a Technol- to water stress, which are derived from some ogy Centre. Another approach is to initiate joint model plants (e. g. Resurrection plants) for use ventures with SMEs, such as our recent idea to in developing more robust crops with improved establish a testing laboratory via an action be- biomass yield productivity and quality traits un- tween the Faculty of Chemistry (UoP) and der adverse and/or erratic environmental condi- Komihris Ltd., (supporting SMEs for the tions. This technology is aimed at improving the Biosupport project submission) where the invest- agricultural production to better adapt it to the ment will come from the company and the ex- erratic, unpredictable conditions under the ef- pertise - from the University side. fects of climate change and should ideally in- The strengths of the Genomics Research volve active participation of European SMEs and Center (GRC) at UoP should now be evident. To industry, increasing its competitiveness. call that the research conducted at the GRC fo- Increasing the Food Quality and Safety cused would be doing the department some- via Production of Doubled Haploids and Hy- thing of an injustice. It covers vast areas of bio- brid Seeds science, concentrating on the food we eat, the High-precision breeding by combining dou- medications we take and the environment we bled haploids and marker-assisted selection,
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able. Existing protein production platforms are urrection plant, Haberlea rhodopensis. This is an expensive and have limited capacity and incredibly drought-resistant plant from which scalability. Transient expression platforms over- genome sequencing could provide a recipe for come these limitations by combining the advan- creation of highly drought-tolerant crops. tages of traditional protein production systems Cancer Research (Oncogenes Regulation) (containment, precise growth conditions) with Cancer is currently one of the leading causes speed, scalability and economy. Therefore, this of death and has caused many public health technology offers an innovative, scalable and concerns in the present. Latest research has sustainable platform for inexpensive production made important progress in illuminating one of of safe and effective biopharmaceuticals, ex- the molecular mechanisms and damaged genes ceeding the performance of current production involved in cancer. One such example is the dis- technologies. Importantly, harmonized interna- covery of microRNAs (miRNAs), leading to a sud- tional regulations would greatly improve the den escalation in research implicating these tiny prospect of commercialization of transient ex- RNA molecules as key factors in cancer biology. pression technologies. Recent studies indicate that miRNAs will most The research group involved in this biotech likely have a diagnostic, prognostic, and therapeu- company has an experience in different antigens tic value. Research has provided evidence for expression in plants using stable and transit ex- potential use of miRNA expression profiling as a pression which is a part of the EU FP7 project novel tool in cancer diagnosis. Currently, there PLAPROVA. are three commercially available molecular diag- De Novo Sequencing of Eukaryotic Geno- nostic tests for cancer based on microRNAs, all mes from Rosetta Genomics. The power of high-throughput DNA Molecular Studies of Schizophrenia and sequencing technologies is being harnessed by Autism fop Medical Practice Implementation researchers in order to address an increasingly Despite the apparent assumption that the diverse range of biological problems. The scale only suitable material for testing and validation and efficiency of modern sequencing provides of biomarkers associated with mental illness is unprecedented progress in many areas ranging the brain, a new direction in the search for from the analysis of genomes themselves to biomarkers for autism and schizophrenia is pro- how proteins interact with nucleic acids. This se- filing the expression of the non-protein encod- ries highlights the breadth of next-generation ing genes of micro RNA in cells from peripheral sequencing applications and the importance of blood. Micro RNA molecules are small regulatory the insights gained through these methods. RNA molecules that show a change in the pat- As part of the BioSUPPORT project, the GRC tern of expression in many diseases. The specific will obtain next-generation sequencing equip- micro RNA profile of bodily fluids such as pe- ment. This unique equipment will enable ripheral blood showed a high diagnostic value, sequencing and analysis of the genome of an which offers benefits such as a relatively non- individual person. Scientists will eventually be invasive diagnostic test. Micro RNA molecules as able to use genomic information to predict what potential biomarkers have objectively measur- diseases a person may suffer from throughout able biological characteristics that can be used as life, as well as attempt to either minimise the indicators of normal or pathological processes. impact of that disease or avoid it altogether Peripheral blood cells as a dynamic reflecting through the implementation of personalised, pre- system allow profiling of micro RNA expression, ventive medicine. Full genome sequencing will which makes possible their use as potential rapidly lead to Predictive and Personalised Medi- biomarkers. From this perspective, micro-RNA cine and will mark a significant leap forward in molecules are considered as a potential new the clinical genetic revolution. Moreover, we will class of biomarkers for many diseases including be able to sequence de-novo genomes of impor- disorders of the central nervous system (CNS). tant organisms. We intend to sequence one res- The use of these discoveries leads us to more
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The new laboratory of Plant Microspore Cultures established by the project number of scientists has increased mostly on the Creation of new varieties of vegetable crops basis of research grants and today the Faculty with a better nutritional value and content of of Biology employs around 50 people working in substances beneficial to health is the goal of this the field of Genomics, Systems Biology and lab. This technology is based on using Micro- Bioinformatics and affiliates around 40 more spore cultures, which can then be used for the researchers working in the field of food analysis production of dihaploid plants which can serve from the Faculty of Chemistry and Faculty of as the basis for breeding hybrid plants with de- Physics. sirable qualities. For this, purpose a new labora- Project from Bulgarian National Science tory for Plant Microspore Cultures was built. Fund (BNSF) - Developing a regional university The Laboratory is equipped with 2 laminar cabi- centre for teaching and research in the field of nets, an inverted microscope, a fluorescent micro- genomics and bioinformatics - coordination. scope, centrifuges, several thermostats, as well as Project from BNSF Developing a Labora- other lab necessities and consumables (supple- tory for Food Analysis- participant; coordinated mented by another project). The laboratory is by University of Food Technology. now fully functional and is producing microspore PLAPROVA - Plant Produced Vaccines - FP7 cultures from tomato, pepper and red beet. The Integrated Project - participant. primary purpose of the laboratory is to produce BIONET - CSA FP7 project - KBBE NCPs haploid and double haploid plants from agricul- Network - participant. Good influence for turally important species to be used by biotech BioSupport dissemination. companies for plant breeding. With this lab, the Experience of the Genomics Research Project will help Bulgarian Plant Biotechnology Center Ltd. Spin-off and its per se implementation of the Systems Green biotechnologies facilities Biology in agricultural practice.
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Table 1. Areas of research Excellence where the GRC can connect to the industry
Areas of Research Collaborative Entities Generated Marketing Excellence Leads (per Research Research/Academic Corporative Area of Interests) Plant Breeding Technolo- University of Plovdiv, Genomics Research Monsanto, Pioneer, Beyer gies for Drought Re- Dept. Plant Physiology Center Ltd. (Spin-off - Crops Science sistance and Molecular Biology; SME) Agrarian University, Plovdiv Doubled Haploid and University of Plovdiv, Genomics Research Bayer Crop Science, Hybrid seeds Production Dept. Plant Physiology Center Ltd. (Spin-off - Group Limagrain, KWS for Crop Plant Breeding and Molecular Biology SME) AG, Monsanto, DuPont, Syngenta Plant Breeding for Bio- Genomics Research Velboy Ltd., Bulgaria Biomass, Biofuel and mass and Biofuel (Pau- Center Ltd. (Spin-off - Timber Industry; Agri- lownia and Brachypodi- SME), Fruit Tree Insti- cultural Research um Breeding) tute Service (ARS) Novel Biodiversity Sour- University of Plovdiv, Agriculture Practice, FAO ces for Improving Food Vegetable Institute, Crops Quality Plovdiv Development of Tran- University of Plovdiv, Genomics Research World Pharmacy Com- sient Expression Systems Dept. Plant Physiology Center Ltd. (Spin-off - panies for Rapid Production of and Molecular Biology; SME) Biopharmaceuticals (Vac- Agrarian University, cines and Antibodies) Plovdiv De Novo Sequencing of University of Plovdiv, Genomics Research LGC, ServiceXS, BGI, 1000 Drought Tolerant Plants Genomics Research Center Ltd. (Spin-off - Genomes Project, Genomes Center SME) Welcome Trust Sanger Institute Cancer Research (Onco- University of Plovdiv, Genomics Research Rosetta Genomics genes Regulation) Genomics Research Center Ltd. (Spin-off - Center, Medical Univer- SME) sity, Plovdiv Molecular Basis of University of Plovdiv, Medical Practice, Indi- Schizophrenia and Au- Genomics Research vidual Medicine tism Center, Medical Univer- sity, Plovdiv Animal Cell Cultures University of Plovdiv, SIGMA Life Science Models for Medical Use Dept. Biology of Devel- opment; Medical Uni- versity, Plovdiv Analytical Methods for University of Plovdiv, Komihris Ltd. (SME) Food Industry Food Quality and Safety GRC, Food Technology Testing University Monitoring of Bioactive University of Plovdiv, Tsvetelina Ltd, Bulgaria, Nestlé Europe, Unilever Components in Func- Dept. of Biochemistry LB Bulgaricum Bulgaria, DMV Nutrition, tional Foods and Microbiology, Dept. DANONE Bulgaria, of Experimental Physics Biological Pest Control University of Plovdiv , Beneficial Insects Co. Symbiont Dept. Plant Physiology and Molecular Biology Bioinformatics University of Plovdiv, Genomics Research Rosetta Genomics Genomics Research Center Ltd. Spin-off Center
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MOLECULAR PHOTONICS LABORATORY FOR ULTRAFAST SCIENCE AND TECHNOLOGY AT SOFIA UNIVERSITY ST. KLIMENT OHRIDSKI
Ivan Buchvarov1, Ivan Petkov2, Anton Trifonov1 1Physics Department, Sofia University St. Kliment Ohridski 5, J. Bourchier Blvd., 1164 Sofia, Bulgaria 2Chemistry Department, Sofia University St. Kliment Ohridski 1, J. Bourchier Blvd., 1164 Sofia, Bulgaria
BASIC CONCEPTS AND MISSION velopment of new technologies. Furthermore, its Molecular Photonics is an emerging field of goal is to advance bio-research and photonics research located at a strategic crossroad where engineering - by focusing its intellectual, scientific, physics, chemistry, engineering and life science educational and industrial outreach efforts on meet. These four closely interacting areas pro- the rapid and directed development of molecu- vide a relevant multi-disciplinary background as lar photonics technology. In doing so, the first well as timely motivations for the development strategic roadmap for molecular photonics re- of molecular photonics at ultimate time and search in Bulgaria will be formulated. MPLUST space scales. Applied and technological as well will coordinate activities within three Sofia Uni- as exploratory and fundamental issues related versity departments and a number of foreign to light matter interaction in organic or inor- partners, and will devote efforts in building an ganic-organic hybrid systems at micro and nano- extensive network of relationships with other scale are now increasingly at the focus of re- universities, industrial partners, and other molecu- search in molecular photonics. lar photonics research groups abroad. While the The Molecular Photonics Laboratory for majority of MPLUST investigators are distin- Ultrafast Science and Technology (MPLUST) at guished for their substantial individual contribu- Sofia University is designed first and foremost to tions to organic photochemistry, laser physics, promote contemporary scientific research and molecular photonics, ultrafast spectroscopy, the education. We implement photon-based meth- establishment of this new research lab is ex- ods with femtosecond timing to record molecu- pected to greatly enhance their research poten- lar dynamics, which fully resolve the primary tial by placing an emphasis on the vertical inte- processes. A focus of the experimental and gration of knowledge. theoretical work is electron, proton and energy IMPORTANCE OF THE LABORATORY RE- transfer, which have fundamental importance for SEARCH FIELD the building blocks of life profound impact on The speed of the molecular dynamics is given the development of new photonics technologies. by the speed of elementary chemical processes With the laboratory equipment we are able to within the molecules. Dynamics is often classified excite coherently multiple electronic states and according to time scale. The focus of the effort to probe the evolution of the resulting electronic described here is on the ultrafast time scale of wave packet with femtosecond resolution. Addi- femtoseconds (1 fs = 10-15 s) to picoseconds tionally, the laboratory tools allow high degree of (1 ps = 10-12 s). This is a typical time scale of el- coherent control over the outcome of chemical ementary chemical reactions and of electronic reactions. and nuclear motions in molecules. Although The MPLUSTs mission is to perform there is an assumption that practical chemistry multidisciplinary research in the basic science and and biology occur on much longer time scales, technological applications of ultrashort laser these longer time scales are often reached by pulses, to educate students from a wide variety adding statistical probability to the short time of backgrounds in the field, and to spur the de- scale dynamics of molecules. Furthermore, bio-
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vides broad probing window, spanning from the Titanium:Sapphire based pump laser that pro- UV to the NIR spectral range. The white light (or vides a pulse train of femtosecond pulses (130 super-continuum) method is highly advanta- fs) with energy of 3.5 mJ at 800 nm, and repeti- geous over conventional (single wavelength) tion rate of 1 kHz. The output beam is divided pump-probe technique in its capability to capture into several fractions by the beam splitters. A and resolve reactant, intermediate and product portion of laser output (250-300 ìJ) feeds a states simultaneously. By measuring the pump- commercial non-collinear optical parametric am- probe spectra as a function of time one not only plifier (NOPA) to generate the pump pulses will obtain kinetic traces at multiple wavelengths while another small fraction of the laser output but also will monitor the complex spectral evo- (5 ìJ) is used to generate the white light (WL) lution. Local and interchromophore transitions for broadband probing. The output of the NOPA can be simultaneously detected, and detailed in- is compressed to have pulse durations as short formation such as spectral intensities and shifts, as 30 fs. The typical tuning range of the NOPA line shape and band width changes can be read- is 480-900 nm and its output can be used di- ily detected and analyzed. Induced excited state rectly to pump the sample. If pump pulses absorption (ESA) peaks are typical signals ap- deeper in the UV range are desired, an optional pearing in broadband pump-probe spectra; but frequency doubling of the NOPA output is used besides these, other contributions may also be to produce pump pulses with wavelength in the observed depending on the spectral range of ~240 - 450 nm range. In the real experiments, interest, such as stimulated emission from excited the generated pulses (NOPA output and its sec- states and ground state bleaching. On the one ond harmonic) are optimized by additional prism hand, the transient signals with varied compressors (not shown in the scheme) to com- spectroscopic origins might mix together, compli- pensate for group velocity dispersion. cate the spectra and add difficulties to the com- The changes in optical density are measured ponent assignments; on the other hand, however, by probing with a femtosecond white-light con- they offer more comprehensive spectral infor- tinuum (WLC) generated by tight focusing of a mation and thus reveal more detailed dynamic small fraction of the laser output into a thin processes. Sapphire or CaF2 monocrystal plate. By this Figure 1 is a schematic representation of the means, a usable probe source that covers the femtosecond broadband pump-probe experi- UV-VIS-NIR spectral range (from 300 to 900 mental setup. The laser source is a commercial nm) is achieved.
Fig. 1. Schematic representation of the UV-VIS-NIR broadband pump-probe experimental setup
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To improve sensitivity of the measurement, In this arrangement, the time resolution is transient absorption spectrometer implements around 100 fs, depending on the wavelength of dual-beam probe geometry and a digital lock-in the excitation pulses and sample optical thick- technique. The WLC is split into two beams ness. It is practically measured by the cross-cor- (probe and reference) and focused into the relation function between pump and probe sample using reflective optics. The probe beam pulses in a liquid or solid-state transparent me- passes trough excited volume of the sample and dia. The spectral resolution of the spectrograph the reference passes through the non-excited is 3-5 nm in the entire UV-VIS range. spot. After passing through the sample, both Femtosecond Pump-Repump-Probe Spec- probe and reference are spectrally dispersed by troscopy an imaging polychromator and simultaneously Many of the photo-induced chemical reac- detected on a TEC-cooled CCD. The signals are tions occur via series of elementary steps includ- collected in a two-step measurement cycle. In ing various short-lived intermediate species. The each step probe and reference signals are re- latter can show very similar absorption spectrum corded at certain conditions determined by the hindering the detailed understanding of complex state of the pump shutter (or chopper). The photo-chemical reactions by pump-probe change in optical density is obtained using the spectroscopy. The problem could be overcome standard formalism for pump-probe using the recently developed pump-repump- spectroscopy [3]: probe (PREP) technique [4]. This method is simi- lar to the pump-probe spectroscopy discussed I exc I 0 = − pr pr just above, but an additional third pulse is used OD log10 exc 0 (1) I ref I ref for excitation of the intermediates involved in where the lower index denotes the recorded the relaxation dynamics. Secondary excitation of probe (pr) and reference (ref) signal, respec- the short-lived species could change the reaction tively. The upper index characterizes the setting pathway yielding novel information on the re- of the shutter which controls the excitation laxation dynamics. The method also allows opti- beam: (ex): pump shutter is open; (0): pump cal manipulation of chemical reactions [4]. shutter is closed. The experimental set-up used for the PREP The recorded signals at each step are result experiments includes an extension of the com- from integration, typically for several 100 laser mercial UV-VIS-NIR femtosecond broadband pulses. The exact number of acquired laser shots pump-probe system described above. The neces- within a single two-step cycle is selectable and sary modification includes a source for second- will depend on the specific experimental condi- ary excitation of the sample and an additional tions. optical delay stage for precise control of the The WLC probe pulse passes through several relative delay of the secondary pulse, related to optical elements which introduce a chirp due to the first excitation pulse. In particular, the inter- the group velocity dispersion (GVD), i.e. its differ- mediate species involved in the electron ent spectral components accumulate different photodetachment of neat water and aqueous group delays. As a result, different spectral com- electrolytes are expected to show strong ab- ponents of the WLC pulse are interacting with sorption on the Ti:Sa laser wavelength of 800 the excited sample molecules at different delay nm. Therefore, in this experiment the secondary times. Before entering the sample the WLC excitation pulse is derived directly (typical energy spreads in time typically from several hundred fs of about 5 uJ) of the regenerative amplifier out- up to ps depending on thickness and the refrac- put. tion index dispersion of the passed optical ma- RESEARCH AREAS AND SCIENTIFIC terial. Independent measurements of the chirp PROJECTS of the WLC will be carried out to correct the The main research areas of the MPLUST are: pump-probe spectra for time-zero differences. electron transfer reactions in solutions; photo- induced dynamics in DNA; early-stage resonant
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energy transfer in lanthanide-organic complexes probe light sources, the spectrograph, the CCD as well as ultra fast temperature jumps in hy- detection array and some of the optical compo- drogen bonded systems. nents for steering the IR beams. Roadmap for the future development of Time-resolved fluorescence spectroscopy the research laboratory until 2015 (Femtosecond Fluorescence Up-Conversion The schematic of the main instruments and Spectroscopy) provides a powerful technique corresponding expansion in the methods for for investigating electronic properties of solids time resolved analysis available at the Laboratory and liquids. Several different techniques have are shown on Figure 2. been used for this purpose over the last four Development of UV-pump-IR-probe and decades. Streak cameras have been used suc- IR-pump-IR-probe spectroscopy will be a cessfully; however, their use is limited to the vis- powerful approach to elucidate the evolution of ible and very near-infrared spectral regions and molecular structures during ultrafast processes their usable time resolution in the synchroscan by monitoring vibrational marker modes in real mode at high repetition rate has been limited to time. This technique can monitor the site-specific about several picoseconds. Optical Kerr cells can interactions in hydrogen bonds and the conver- provide subpicosecond time resolution, but their sion between excited electronic states by inspec- low efficiency limits the technique to strong sig- tion of the fingerprint IR-active vibrations in con- nals. The well-established techniques for growth junction with quantum chemical calculations. of high quality nonlinear crystals allow measure- This spectroscopic technique is a straightforward ment of fluorescence time evolution with extension of the pump-probe method developed subpicosecond time resolution using fluores- in the first three years of the project. The fun- cence upconversion technique. The contempo- damental arrangement of the setup, i.e. the tem- rary state-of-the-art femtosecond upconversion poral sequence of the laser pulses and the de- spectrometers can provide time resolution of tection scheme will remain unchanged. The only <100 fs. However, dispersive elements in collec- components that need to be replaced are the tion optics prevented measurement of spectra
Fig. 2. Layout of the main time-resolved instruments and methodologies, available at MPLUST. The blocks are shaded in order to show the roadmap of the acquired equipments. The dark gray marks the equipment acquired during the establishing of the laboratory, light grey - instruments planned for the future.
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MADE IN BULGARIA WITH EUROPEAN SUPPORT
SENSOR EFFECTOR BOOT MODULE FOR A NEW TECHNOLOGY SPINAL PATIENTS REHABILITATION
Lidia Ilieva-Mitutsova1, Ivan Chavdarov2, Nikolay Serbenyuk3, Alexander Platonov3, Oleg Trifonov3, Viktor Yaroshevsky3 1Institute of Mechanics, Bulgarian Academy of Sciences Acad.G. Bonchev Str., bl.4, 1113 Sofia, Bulgaria 2Institute of system engineering and robotics, Bulgarian Academy of Sciences Acad.G. Bonchev Str., bl.1, 1113 Sofia, Bulgaria 3Keldysh Institute of Applied Mathematics, Russian Academy of Sciences 4 Miusskaya Sq., 125047 Moscow, Russia Abstract study of the problem and development of new In this paper we represent the development methods and devices for the support-locomotion of a mechatronic sensor effector boot module recuperation. One of the methods of restoring for effective rehabilitation of patients in the the support-locomotion functions is to affect early post-traumatic stage (1 month) after the the neurons of the spinal cord using the limb occurrence of a serious spinal-cord trauma or reception system as a natural communication poli-trauma. The module is optimised by size and channel. Foot receptor activation is applied for by weight and it can apply into independent that purpose. The objective of this study is to portable device with assurance for vertical posi- complete the following tasks: (i) to affect the tion in the bed of the immovable patients. extra receptors, which signals stimulate the cen- The device includes: a module for basing and tral locomotion generator located in the spinal fixation of the patients leg, a sensor SkinTouch cord; (ii) to affect the nerve endings in the bio- for measuring bio-electrical impedance in points logically active zones, stimulating functioning of of the foot skin, a mechanism for acupressure, a internal organs of a seriously disabled patient. carriage module for basing of a measuring sen- The start of the procedure during the early post- sor and a mechanism for acupressure, à module traumatic stage (after the occurrence of a spi- positioning of carriage module to various foot nal cord trauma or poli-trauma) is considered to points for the programme performance of the be appropriate for the decrease of atrophy procedures and PC controlled sensor and effector speed. Receptors stimulation is proposed at the elements connected to the physicians monitor. start of the recuperation procedure, only due to The studies are carried in Bulgarian Academy patients poor physical state. A method of of Sciences (BAS) - Russian Academy of Sciences acupressure and multi-point trajectory of area (RAS) collaboration advance to develop a new activation is selected for application, combined device for treatment of spinal patients and cre- with methods of reflexotherapy. ating new technologies of their rehabilitation. Technical solution of mechatronic sensor effector boot device INTRODUCTION The device includes: Serious disability and recent increase of a a module for basing and fixation of the number of spinal cord injuries imply a profound patients leg,
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a sensor SkinTouch for measuring bio- electrical impedance in points of the foot skin, a mechanism for acupressure, a carriage module for basing of a measur- ing sensor and a mechanism for acupressure, a module for a plane motion and position- ing of carriage module to various foot points for the programme performance of the procedures, PC controlled sensor and effector elements, connected to the physicians monitor. The mechanical modules are designed in In- stitute of mechanics, BAS. The specialized sensor SkinTouch for measuring bio-electrical imped- Fig. 1. General view of the module for basing ance in points of the foot skin is developed in of the patients leg the Institute of Applied Mathematics Keldish- RAN. of the foot are prepared fixations 3, which loca- The design, modelling and experimenting of tion is regulated longitudinally according to the the separate modules are presented below. foot size. The surface of the foot remains un- Design of a module for basing and fixa- covered for a direct contact to each point for tion of the patients leg measurement of the skin electrical resistance Requirements to module for basing and and acupressure. fixation of the patients leg A carriage module for basing of a measur- The designed module must meet the follow- ing sensor and a mechanism for acupressure ing requirements: Combined module - carriage (Fig. 2) com- 1. Sustainable basing the patients leg, which is prises carriage 1, to which module for in a bed. acupressure 2 and a measuring module 5 are 2. Accessibility to be ensured to maximum immovably attached. Two linear drives, by means number of points on the foot with the aim to of which a translation along axis Z is realised, are measure the bioelectrical resistance by means of included respectively in the modules joints. a specialized sensor. The respective useful contact pressure of an 3. Accessibility to maximum number of points electrode for measurement 4 is achieved by on the foot for automatic acupressure perform- ance according to a programme assignment, in- dividually for each patient. 4. Discomfort must not be created to the patient, and also not to influence the precision of the carried out measurements. 5. Basing to be possible at different patients feet sizes. 6. Safety of the patients to be ensured of the device activity at arising programme or mechani- Fig. 2. A carriage module for basing sensor cal reasons. and effector elements of device View of the module for basing and fixa- tion of the patients leg means of drive control and the external force The developed module includes the following (acupressure) is regulated by means of the ex- components: (Fig. 1): 1- heel support, 2 - foot ecutive mechanism 3. fixations, 3 - regulated foot fixing of the leg. A mechanism for acupressure The foot is based at support 1. The leg is The mechanism for acupressure includes fixed above the ankle joint and in the front part (Fig. 3) translation linear drive 1 and removable
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instrument with different number of pins 2 (Fig. a screw-carriage 9. 4). The drive 6 is fixed on the base-carriage 5 witch by means of the gear 7 activates the screw- carriage 9. It moves by itself the carriage module 9 along axis Y lead on the guide 8. It is necessary the translation run to be equal to the
width of the foot H2 . Lp ( 40 to 60mm.
Fig. 3. A mechanism for acupressure
Fig. 4. Effector instruments with different number of pins
Effector instruments with different number of pins are applying for receptor activation by Fig. 6. Basing of the patients leg for the the method of skin-deep multi-pins acupressure programme performance of the procedures combined with methods of reflexotherapy. Design of a module for a plane motion Fig. 6 shows basing of the patients leg on the and positioning of carriage module to vari- module with possibility for connection sensor ous foot points and effector instruments to various foot points Movement along axes X and Y is realised by for the programme performance of the proce- two mechanisms respectively (Fig. 5). dures. The mechanism for longitudinal translation X Development of the sensor SkinTouch includes: a foundation 1, a drive 2, a leading screw for measuring bio-electrical impedance in a 3 and a guide 4 for translation along axis X. It is skin point necessary the run of this translation to be equal Proof of the design necessity of a special-
to the length of the foot H1 . 110 to 150mm. ized sensor for measuring bio-electrical im- The mechanism for translation along axis Y pedance includes: a base-carriage 5, a drive 6, a gear 7 and The device measuring both the initial (pre- treatment) foot skin electro-conductivity, as well as the current one operating during the process of medical treatment, is of essential importance for the successful stimulation of patients foot. Such a sensor is needed to design a high-spatial resolution map of acupuncture points of a pa- tients foot, and the map should be used to analyze the results of the treatment. The com- plexity of the registration needed originates in the measurement of current extremely low val- ues. Note that current low value is due to the high ohm resistance of patients foot skin, and to the restriction of voltage applied to patients Fig. 5. A module for a plane motion and skin. That restriction is imposed to avoid not only positioning of the carriage injury or pain, but also data distortion due to the
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Fig. 7. Principal scheme of the measuring device SkinTouch
Fig. 8. General view of the device in the bed of the immovable patient
Fig. 9. 3D model of a mechatronic sensor effector boot device
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○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ are performed. Serbenyuk, O. Trifonov, V. Yaroshevskiy. A high sensi- tivity device for measuring bio-electrical impedance of View and modelling of the sensor effec- human skin. Proceed. of Inter. Conf. Advanced Prob- tor boot device lems in Mechanics 2010, July 1-5, St. Petersburg, 2010, Product Mechanical Desktop 2005 is applied on CD (2010), ISBN 5-98883-009-9. for creation of a virtual 3D model of the mod- [3] A. Ïëàòîíîâ, Þ. Ãåðàñèìåíêî, Ë. Èëèåâà- Ìèòóöîâà, Î. Íèêèòèí, Í. Ñåðáåíþê, Ä. Òðèôîíîâ, Â. ule. The program MSC. visual Nastran 4D 2002 ßðîøåâñêèé. Áèîìåõàòðîííûå ýëåìåíòû ñòèìóëÿ- for computer simulation is applied on the 3D òîðà ñòîïû ÷åëîâåêà. Ïðåïðèíòû ÈÏÌ èì. Ì. Â. model. Êåëäûøà, 2011, ¹38, 32 ñ. ISSN 2071-2898.
CONCLUSIONS ÑÅÍÇÎÐÍÎ-ÂÚÇÄÅÉÑÒÂÀÙ ÌÎÄÓË-ÎÁÓÂÊÀ Conclusions derived after modelling and ÇÀ ÍÎÂÀ ÒÅÕÍÎËÎÃÈß ÍÀ ÐÅÕÀÁÈËÈÒÀÖÈß simulation help successful realization of the pro- ÍÀ ÏÀÖÈÅÍÒÈ Ñ ÃÐÚÁÍÀ×ÍÎ-ÌÎÇÚ×ÍÀ ÏÀÒÎËÎÃÈß totype of the portable module for procedures with supporting and healing effect of patients in Ëèäèÿ Èëèåâà-Ìèòóöîâà1, Èâàí ×àâäàðîâ2, 3 the early stage after the occurrence of a spinal Íèêîëàé Ñåðáåíþê , Àëåêñàíäúð Ïëàòîíîâ3, Îëåã Òðèôîíîâ3, cord trauma or politrauma. 3 Âèêòîð ßðîøåâñêèé The following scientific and application results 1Èíñòèòóò ïî ìåõàíèêà, Áúëãàðñêà àêàäåìèÿ íà are expected: íàóêèòå 1. Measuring of the bioelectrical resistance to be óë.Àêàä. Ã. Áîí÷åâ, áë.4, 1113 Ñîôèÿ, Áúëãàðèÿ 2Èíñòèòóò ïî ñèñòåìíî èíæåíåðñòâî è ðîáîòèêà performed in the foot points for each individual óë.Àêàä. Ã. Áîí÷åâ, áë.4, 1113 Ñîôèÿ, Áúëãàðèÿ patient by means of a specialized sensor Skin 3Èíñòèòóò ïî ïðèëîæíà ìàòåìàòèêà Ì.Â.Êåëäèø, Touch. An individual chart of the acupuncture Ðóñêà àêàäåìèÿ íà íàóêèòå Ìèóñêàÿ ïë., 4, 125047 Ìîñêâà, Ðóñèÿ foot points of the patient is built up. 2. Planning and performing of treatments Ðåçþìå (acupresura) in definite points, along a defined Ïðåäñòàâåíà å ðàçðàáîòêàòà íà ìåõàòðîíåí ñåíçîðíî-âúçäåéñòâàù ìîäóë-îáóâêà çà åôåêòèâíà trajectory or an area on the foot. ðåõàáèëèòàöèÿ íà ïàöèåíòè â ðàííèÿ ïîñò-òðàâ- 3. Performing of a periodical estimation and ìàòè÷åí ñòàäèé (1 ìåñåö) ñëåä òåæêà ãðúáíà÷íî- control of the treatment results by means of ìîçú÷íà òðàâìà èëè ïîëèòðàâìà. Ìîäóëúò å îïòè- measuring of the bioelectrical resistance in defi- ìèçèðàí ïî ðàçìåðè è òåãëî, è ìîæå äà ñå ïðèëàãà êàòî íåçàâèñèì ïîðòàòèâåí óðåä, ïîñòàâåí âúâ âåð- nite foot points. The healing programme under- òèêàëíî ïîëîæåíèå â ëåãëîòî íà èìîáèëèçèðàíèÿ goes a consecutive variation if necessary. ïàöèåíò. The mechatronic sensor effector boot device Óðåäúò âêëþ÷âà: ìîäóë çà áàçèðàíå è ôèêñèðà- íå êðàêà íà ïàöèåíòà, ñåíçîð SkinTouch çà èçìåð- can be applied in the clinic practice after per- âàíå áèî-åëåêòðè÷íîòî ñúïðîòèâëåíèå â òî÷êà îò forming technical, laboratory and clinical experi- ïîâúðõíîñòòà íà ñòúïàëîòî, ìåõàíèçúì çà àêóïðå- ments. ñóðà, ìîäóë-êàðåòêà çà áàçèðàíå íà èçìåðèòåëíèÿ ñåíçîð è ìåõàíèçìà çà àêóïðåñóðà, ìîäóë çà ïîçèöèîíèðàíå íà ìîäóëà-êàðåòêà â ðàçëè÷íè References òî÷êè íà ñòúïàëîòî çà ïðîãðàìíî èçâúðøâàíå íà ïðîöåäóðèòå è ÐÑ çà óïðàâëåíèå íà ñåíçîðà è [1] Ilieva-Mitutsova L., Chavdarov I., Vitkov V., èçïúëíèòåëíèòå åëåìåíòè, ñâúðçàí ñ ìîíèòîðà íà Yaroshevsky V. A mechatronic module modeling for ëåêàðÿ. foot receptor activation. Proceed.of Inter. Conf Èçñëåäâàíèÿòà ñà ïðîâåäåíè â ñúòðóäíè÷åñòâî Engineering Mechanics 2011", May 9-12, 2011, Svratka, ìåæäó Áúëãàðñêà àêàäåìèÿ íà íàóêèòå è Ðóñêà Czech Republic, pp. 231-234, (ISBN 978-80-87012- àêàäåìèÿ íà íàóêèòå è ñà íàñî÷åíè çà ðàçâèòèå íà 33-8). íîâè ñðåäñòâà è òåõíîëîãèè çà ðåõàáèëèòàöèÿ íà [2] A. Platonov, V. Vitkov, L. Ilieva-Mitutsova, N. ïàöèåíòè ñ ãðúáíà÷íî-ìîçú÷íà ïàòîëîãèÿ.
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Simeon Trifonov, Head of Development Department AMK Drives and Controls, Ltd. 1, Gen. Nikolov Str., 5300 Gabrovo, Bulgaria
Together with the rapid development of PLC placed by their software analogues. Such are technologies, nowadays, the requirements for gearbox, cam gears, position-signalling mecha- short engineering and commissioning times are nisms, coupling and decoupling mechanisms and growing more and more. At the same time im- many others. Software analogues make the posed is the conflicting requirement for lower- work easier thanks to the good connection be- ing the ready products price. To meet these re- tween the servo-mechanisms (which have also a quirements, two interesting trends can be seen in predominant software part) and the controlling the field of automation. One of them is the per- system.). Comparison between the software and manent strive for increasing the software reali- the mechanical implementation of a simple, but zation of the part, controlling the motion, on the often used, mechanism - the gearbox. is shown account of the mechanical part (Fig. 1). This in the table (Table 1). trend makes sense, since the software can be changed and developed much easier than the The general part of the implementation is hardware. Another advantage here is that this usually related to the driving and controlling approach substantially reduces the price for de- part. It is therefore of great importance for the velopment of the product, as expenses are made controlling part to be well developed and only for software development, but no new ma- enough adaptive. Due to the presence of pow- terials are introduced. Correcting the design er- erful microprocessors today, it is possible the rors is also performed much easier. controlling part to be integrated in the control- Many machine structures can be easily re- ler, where the logic is. This, in a great extent, re-
Fig. 1. Trend for decreasing the mechanical part of the automation systems
Table 1. Comparison between the software and the mechanical implementation of a gearbox
Criterion Software implementation Mechanical implementation Reliability High, constant in time Depends on the make, decreases in time Possibility for varying the ratio Yes No Performance High, depends on the Limited, depends on microprocessor performance the material, make, ... Maintenance costs None Usually, yes
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Fig. 2. The trend for integration of the motion control in the PLC duces the overall costs of the system. It is there releasing the program modules; where the second trend in the field of automa- ability to work both with local access (for tion manifests - integration of the motion con- integrated in the servo-mechanisms programma- trol in the PLC itself (Fig. 2). ble controllers) and with external (accessible More and more the PLC manufacturers are through industrial interface); emphasizing on developing library modules for purpose dependent organization of the li- facilitating the quick implementation of applied brary modules in library files and groups. projects. Libraries make it possible for the ap- The AMK company offers a wide range of plied software developers to focus their efforts program modules for servo-mechanisms control. on the details, specific for the particular applica- Here are examined only few of them. tion, using multiple ready-made units - for giving Servo-mechanisms are often required to ro- commands to the servo-mechanisms, often used tate with definite speed, as also the acceleration algorithms and even ready-to-use technologies. ramp, or deceleration ramp, may appear to be The new generation of the AMK company more important. There are also applications controllers are based on the contemporary tech- where this is not enough and forming an S- nologies in the field and contemporary trends in shaped curve of acceleration and deceleration is the development of the contemporary automa- needed, and a jerk is set as well. tion engineering. Developed are libraries with li- For achieving this goal three different inter- brary modules which are meant mostly for the polators of speed are developed - VGEN, motion control. These libraries comply with the VGEN_A and VGEN_AJ. They calculate a posi- following requirements: tion set-point for the servo-mechanism (though to comprise most of the basic functions and here the position is of no importance) guaran- technologies - servo-mechanisms control, ratio teeing an exact set speed of rotation for the implementation (underdrive, overdrive), position- servo-motor. They have similar principles of ac- ing, synchronization of several servo-mechanisms, tion, thus only the most complex one shall be interpolation of complex profiles, synchronization examined - VGEN_AJ. of print marker, binary variables control, depend- The abbreviation AJ is derived from Accelera- ent on the servo-motor position, etc.; tion and Jerk. This interpolator generates (in- fast response (i.e. optimal code) of the li- terpolates) a speed with set by the user accel- brary modules; eration and jerk. Actually, this interpolator makes clear (maximum simplified) interface of the calculations on its output incremental position, as library modules; the increment, compared to the respective time in ability for changing parameters even after the positioning regulator (ID2 - SERCOS cycle
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time) causes rotation of the servo-motor with a of outputs. The action principle of this library speed diVelocity. Several accelerations for a module is shown in detail in Fig. 4. greater flexibility are also set - udAccel (spinning acceleration), udDecel (deceleration) and All the parameters can be changed during the udQDecel (fast deceleration). Several jerks cor- interpolation, as they get into effect timely, but respond there to these accelerations - udAccJerk, the following limitations must be concerned: udDecJerk and udQDecJerk. If the jerk value changes during a constant The library module allows to: acceleration, providing the set speed (or speed 0 generate an incremental position, according upon stopping) will be missed, a decreasing of to the speed, set by the entered parameter; the acceleration with proper (corrective) jerk set individual values of acceleration upon starts immediately (Fig. 5). reaching certain speed and stopping (reaching the speed 0); If the jerk changes during deceleration, fast (emergency) stopping with special, upon reaching the set, or zero speed (the phase, separate value for deceleration (usually greater when this jerk is active), it shall be neglected and than the others); the interpolator shall reach the target speed with setting an independent value for a jerk, cor- the current jerk value. responding to each of the above mentioned If the speed assignment, or the percentage accelerations; change of speed is changed during the accelera- percentage change of the set speed, tion, upon reaching the set speed, this change shall be considered, on condition that boStart = TRUE, boStop = FALSE and boQStop = FALSE. If the changed speed requires reverse acceleration (i.e. to lower speed), the change of direction shall be realized dependent on the set acceleration and jerk through the parameters udAccel and udAccJerk (Fig. 6) Actually, it is deceleration, but with values for acceleration and the jerk upon reaching given speed.
If during acceleration the input boStop is ac- tivated (state TRUE), VGEN_AJ processes first a phase with a jerk, set through the parameter udAccJerk, until it reduces the acceleration to 0 and then starts a deceleration according to the values, given for the parameters udDecel and udDecJerk. Fig. 3. Action principle of the speed generator More different is the behaviour of the inter- polator upon fast stop through activating the through a special input; input boQStop (state TRUE). In this case changing parameters during motion. VGEN_AJ reduces the current acceleration in- The principle of action is explained on Fig. 3. stantly, with the jerk value set by the parameter Relations between the jerk, acceleration, speed udQDecJerk. When the current acceleration and the resultant position are shown graphically. reaches 0, the stopping is performed in accord- To be able to cover multiple customer re- ance with the deceleration value, set through the quirements, the library module VGEN_AJ offers parameter udQDecel and jerk - udQDecJerk. a flexible control, dependent on the signals of The difference between the two ways of several inputs, and the interpolator state is iden- stopping is shown in Fig. 7. tified through proper states of a definite number
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Fig. 4. The library module VGEN_AJ action principle
Fig. 5. Jerk correction upon reaching the set speed
Fig. 6. Reaction of the interpolator VGEN_AJ upon changing the speed
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Fig. 7. Reaction upon normal and fast stopping
The two servo-mechanisms work in a position- control mode and the function of the library modules is to synchronize the motions, reading and interpolating the error within a given scope. The aim is to achieve good synchronization be- tween the transport device and the tool, so the processing of the material, moved by the trans- porting device, to be performed always in ac- cordance with the image, pre-printed on it.
The reasons for marker shifting in the most Fig. 8. Function block VGEN_AJ cases are as follows: inexact printing of the marker (respectively, In Fig. 8 shown is the functional unit the whole image); VGEN_AJ. inexact interrelation between the transport and the tool; Synchronization by print marker (Print Mark external influence on the marker position Control - PMC) is a task often assigned to the (e.g. at temperature changes, stretching the ma- contemporary driving and controlling techniques. terial, etc.). Some companies already provide ready-to-use so- The library modules adapt to the specific re- lutions, but they are rather partial than devised to quirements through giving input parameters, con- satisfy the user needs as a whole. Such applications trolling the synchronization process. The main are oriented mainly to realization on machines and parameters and their interrelation are shown on production lines for the packing industry. Fig. 10. In print marker control there are two motions - of the transporting device, and of the tool, as The used parameters are named in the way the first is synchronized with the latter (Fig. 9). they are defined in the library modules and have The PLC program, using the above described li- the following meaning: brary modules can reside in one of the servo- udModulo - size of the format [inc]; mechanisms PLC, or in autonomous PLC. In both udPmcDist - distance between the tool and cases for communication with the one, or the the sensor [inc]; two, external for the controller servo-mecha- udSetVal - distance between the beginning nisms, synchronous industrial interface is used. of the format and the sensor [inc];
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Fig. 9. Action principle of the print marker control
particular implementation, sometimes it is neces- sary to move the print marker reading sensor away by n formats. To keep the right order of corrections, in this case a FIFO-structure (First In - First Out) shall be used, in which they are memorized and processed in a proper moment, i.e. the calculated difference is compensated n formats later. This functionality is achieved by using two independent library modules - PM_DETECT (for reading the difference and Fig. 10. Parameters, used to synchronize the determining the correction) and PM_CORRECT print marker (for processing the correction), which communi- udCorrStart - beginning of the correction cate mutually through the structure [inc]; ST_CORR_FIFO (FIFO with the corrections) (Fig. udCorrStop - end of the correction [inc]; 11). udDetectWin - window (interval) in which it is expected a print marker to be found [inc]. The delay, by which the PM_CORRECT block The print marker detection is performed makes the corrections, is equal to the difference through a sensor. It reads the actual position of in the formats n between the tool and the print the marker on passing over it, and the error is marker: calculated as a difference between the read udPmsDist −1 value and the expected one. For better reliability, n = the marker reading is performed within an inter- udModulo val, set by the parameter udDetectWin. Thus the x = udPmsDist%udModulo possibility for wrong reading in a section with udSetVal = udModulo.(n +1) − x characteristics similar to those of the print marker, which is not a print marker, is limited. The Depending on which motion is leading and calculated difference is compensated within the which is subordinate, two different implementa- interval from udCorrStart to udCorrStop. tions of PMC can be specified: Due to the technological specificities of the leading tool, synchronization of the trans-
Fig. 11. Block diagram of a PMC
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porting belt (Fig. 12); tion lines, a great amount of unfit for use pro- duction shall be produced before measures are taken for removing the problem. For resolving this situation, the library module REF_RESET has been created. Its input parameters are the signals for found and missed print marker, generated by the library mod- ule PM_DETECT, as well as the maxi- mum allowed number of consecutively missed print markers. When reaching this number, the library module initiates a sequence for a new synchronization, and then the PMC operation continues Fig. 12. PMC - synchronizing the transport normally. This is possible, as far as the above-mentioned basic units for deter- The controller synchronizes the transportation mining the correction and processing have addi- belt by the print marker. The motion of the tool tional inputs for automatic referencing. They can is leading, as it can be performed with constant also be used for initial start-up of PMC. To fa- and with variable speed as well. cilitate the users, all these separate library mod- leading transporting belt, synchronization of ules are united in one module, and between the the tool (Fig. 13). modules are established connections (Fig. 14). The result is a complex library module PMC, which comprises all the necessary functionality. The PMC_BASE module is realized on the basis of PM_DETECT, PM_CORRECT and the necessary com- munication FIFO-structure between them.
Information from the sensor is sup- plied through the input parameters boPmSig and diPmOffs. The Boolean variable boPmSig is directly connected to the signal from it. Through diPmOffs the Fig. 13. PMC - synchronizing the tool difference between the discrete input
value diInVal(kT0) is set and the actual input value diInVal(T ) in the moment of boPmSig The controller synchronizes the tool by the registering an active front of the sensor signal. print marker. The motion of the transporting belt The relation between these values can be pre- is leading, as it can be performed with constant sented through the equation: and with variable speed as well. diInVal(T ) = diInVal(k.T ) + diPmOffs(k.T ) Sometimes, in real conditions, it happens the boPmSig 0 0 print marker not to be read because of a rather This way can be obtained precise information big shift that lets it out of the set window about the moment of reading the print marker udDetectWin or simply because of the fact, that by the sensor, though the PLC reads the input it was poorly printed. If the process gets variables in precisely set cycles. unsynchronized, due to comparatively high pro- To choose the PMC type, we use the Boolean ductivity of such a type of machines and produc-
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Fig. 14. Block diagram of the full PMC functionality variable boInvPmc. As seen in the figure, through this variable we choose the way, in which the fi- nal value of PMC_BASE shall be corrected - through summing up or subtraction. Another feature, to which attention shall be paid, is that through the library module SET_OFFSET an offset can be set, which can be useful during precise adjustment of the ma- chine. Representation of the complex library mod- ule PMC through the programming language Function Block Diagram (FBD), specified by the standard IEC61131-3, is shown on Fig. 15. Performing complex positioning profiles Fig. 15. Function block PMC, represented through contemporary servo-mechanisms is an through FBD often assigned application task. Thanks to the rapid development of the driving techniques motor; nowadays exact processing of these complex by the actual position, received from the profiles does not present such a great problem. encoder, coupled to some leading motion; However, for this purpose a proper interpolator virtual (fictive) generator of assignment. is needed which to generate the position as an The interpolator, on its part, based on data in assignment for the servo-mechanism, which in tabular form, interpolates a position which is fed to turn is set in a position-control mode. a servo-mechanism for execution. In the practice it The AMK company presents a tabular inter- is common between the servo-mechanism and the polator in the form of a library module for the output of the interpolator to be put other library programmable logic controllers (PLC). Its princi- modules, i.e. for realization of print marker control, ple of action is shown on Fig. 16. The aim is on for setting a ratio (electronic gear), etc. the output of the interpolator to be received a The library module has many input and out- position, corresponding to another position, called put variables for realising different modes and leading, according to the rule, described in a for satisfying multiple requirements, imposed by tabular form. the practice. Due to the fact, that similar interpo- The assignment to the interpolator is ob- lators in different literature sources are called tained through one of the following ways: CAM profile interpolator, the library module by the actual position of a servo-mechanism examined is named CAM_PROF (Fig. 17).
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Fig. 16. Action principle of the tabular interpolator
The interpolator can work with three types of tables: Y, XY and XYVA (polynomial). The interpolator action principle using Y-table is shown in Fig. 18. The Y-tables have the ability to receive great amount of information, because they store only y-values; moreover, they are easy to track due to their simple structure. Along with the described above advantages, there is a major disadvantage - the points concentration, dependent on the profile of the set curve, cannot be controlled, as the x-coordinates of the points are equidistant. Fig. 18. Action principle of interpolation by For instance, it is enough a linear section to be Y-table described by 2 points, but generally it shall not be, using a Y-table. too - reduced number of points (the memory volumes for the XY-table and for the Y-table are the same, but the number of points in a XY-ta- ble is twice as less due to setting the full coordi- nates) and the values are difficult to track due to the complicated structure. The parameters for XYVA-tables require more efforts to be determined. They are not suitable for manual generation. For this purpose integrated in the development environment of AMK editor of curves is used, called CAM Editor. Fig. 17. Function block CAM_PROF, repre- XYVA-tables have one basic advantage sented through FBD against the other types of tables - they describe the desired curve in the most precise manner, as interpolations are made through a polynomial of The interpolator action principle using XY-ta- 5-th order: ble is shown in Fig. 19. = + + 2 + 3 + 4 + 5 The XY-tables are good for describing more y(x) c0 c1.x c2.x c3.x c4.x c5.x complex curves, because the distance between This, however, predetermines there great dis- the points by the x-axis can vary. Thus, the re- advantage - long calculation time. They are not dundant points in the linear sections are avoided proper for any type of PLC, and mostly for those and more points are concentrated in the non-lin- which have great power for calculation, as well ear sections. The XY-tables have disadvantages as for arithmetic co-processors (e.g. x86).
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X = max_ new , Xnew Xact. Xmax_ act where:
Xact is the leading position in the current table; X is the leading position in the new table; new
Xmax_act is the resolution in the current table; X is the resolution in the new table. max_new At a synchronised switch of tables there is no loss of position. For this purpose a new external Fig. 19. Action principle of interpolation by logic must be created which to trigger the tables XY-table switch only on value TRUE on the respective out- put boInAck, boOpAck or boOutAck. The output The tabular interpolator CAM_PROF allows variable boOpAck (the same is true for boInAck for switching tables at any time of operation. and boOutAck) remains in TRUE for two cycles This gives a lot of new possibilities for the devel- (two calls) of CAM_PROF. opers of applied projects. The switch can be syn- The tables switch which is not agreed with chronous (upon exiting the current table) or the output variables boInAck, boOpAck è asynchronous (at any time). Moreover, com- boOutAck is called asynchronous. In this case pletely different tables can be switched - of dif- the interpolator takes the new leading position ferent type, number of elements uiNoElement, for a current one and continues the interpolation different resolution by x or by y, etc. At switch- by the new table. This, naturally, leads to a ing tables with different resolution, the new po- change in the relation between the leading and sition on the output of the interpolator is calcu- the interpolated motion. lated by the formula:
PROTOTYPE GIS FOR ANALYSIS AND PROTECTION OF THE BULGARIAN ARCHAEOLOGICAL HERITAGE - ARCHGIS
Stelian Dimitrov, Alexander Kotsev, Anton Popov, Georgi Nehrizov, Tsoni Tsonev Faculty of Geology and Geography, Sofia University St. Kliment Ohridski 15, Tsar Osvoboditel Blvd., 1504 Sofia, Bulgaria
The overall objective of the project Pro- tures, behaviours and conditions of modelled totype GIS for analysis and protection of sites. By doing so and in case of a possible fu- Bulgarian Archaeological heritage is to ture corporate solution of the proposed proto- elaborate a prototype geographic information type GIS, the system will provide the necessary system (GIS) for analysis and protection of the integrated information environment and relevant archaeological heritage in Bulgaria. Accomplish- tools for complex sites modelling. ment of this objective will fill the gap in docu- In relation with the overall objective, the fol- menting archaeological sites in the country, par- lowing specific objectives of the project are ticularly with regard to their spatial characteris- defined: tics and their environment. Development of a Extending the interdisciplinary relations and prototype GIS will be based on the principles of interinstitutional cooperation in solving complex the system approach to ensure the necessary research problems related to the development quantitative information about possible struc- and application of geoinformation technologies
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in archaeological research and protection of the Participants in the project also originate from archaeological heritage. the Centre for Underwater Archaeology in Development of a uniform methodology for Sozopol - CUA, which is the only institution in the solving the existing problems, based on com- country directly involved with promotion and monly agreed standards for identification and protection of the submerged archaeological her- codification of existing archaeological informa- itage in the country. tion as well as on common requirements for What are the main research tasks of the data quality and quantity, position and attributive project? precision of the data included. The proposed archaeological GIS, which is Optimization of the developed prototype subject to development within the proposed GIS after its testing against as many as possible project is actually the information fundament multi-proxy variations relevant to a concrete for the analysis and preservation of the archaeo- modelled territory logical heritage in the country. Creation of a logi- Demonstration of the functional capacity of cally consistent archaeological GIS will be of sig- the system in internet environment with the aim nificant benefit to the archaeological community, to communicate to the scientific community and government institutions and the wide public. The the public with the results achieved. reason is that it will enable high quality visuali- The project activities are carried out by scien- zation and most of all - analysis of the archaeo- tific consortium, in which the leading organiza- logical heritage in combination with its geo- tional role plays the Sofia University St. Kliment graphical environment. The link environment - Ohridski, represented by faculty, postgraduate statistically significant number of archaeological (PhD) and undergraduate students from the sites is new to Bulgarian archaeology and it will Cartography and GIS Department - CGIS (Fac- support the analyses in a completely new way. ulty of Geology and Geography). They will be Such a link will enable researchers to identify directly engaged with the formal project man- patterns in the spatial configuration of sites and agement, coordination of all activities and the the existing trends in the location and geographi- work of all participants. Apart from the leading cal characteristics. Integration of data based on functions in seven of the ten work packages, one a geographical principle will also ease field work PhD and one postgraduate student will also be through integration of the existing with new engaged in elaboration of GIS database and data by using GPS and other surveying tech- field work for data verification purposes. niques, such as total stations, etc. Lastly, the high The second partner on behalf of the Sofia quality cartographic visualization along with the University - Department of Archaeology (DA) ability to create 3-dimensional images and physi- will take part with two faculty members, one PhD cal models and mapping services through the student and one postgraduate student. The en- internet are of particular interest for museums, gagements within the project will be in prepara- since the produced products will ease communi- tion of five out of ten work packages. cation with the public and will create an innova- The National Archaeological Institute with tive environment for presentation of information Museum - NIAM-BAS is a partner of the project to a broad range of users. since this is the institution in charge of standardi- Research tasks which are addressed with this zation and documentation of archaeological in- project proposal are related to advantages for formation in accordance with the requirements the archaeological scientific agenda, which con- for maintenance of the archaeological map of temporary geographic information systems cre- Bulgaria in a digital form. Two researchers who ate. Research tasks in the project include the are directly involved in the AMB maintenance, following: development and improvement are part of this 1. Registration and documentation of ar- project proposal. The NIAM-BAS project team chaeological sites within their geographic set- will lead the development of three and partici- tings. The process of spatial registration, preser- pate in eight work packages. vation, manipulation and visualization of ar-
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fer of specialized knowledge; graphic environment will allow automatic calcu- Use of technologies that correspond to the lation of various characteristics of each point International and European standards for geo- within the territory where geographic data is information systems and exchange of spatial collected. The following thematic layers of geo- data, commonly known under the term graphical data will be elaborated for a decided interoperability1; part of the country in order to ensure the link- Ability to do spatial analyses and high qual- age of archaeology and their geographical envi- ity visualization of geographic data for archaeo- ronment: logical sites, along with their natural environment. Archaeological sites Information, which will be collected and sys- Digital elevation model tematized within the future Geographic informa- Slopes tion system, can be separated into two subordi- Aspects nated levels (partitions): Geological composition 1. Structured information from the previous Geomorphology experience and knowledge of the respective spe- Soils cialists. This partition may be called documental. Land cover 2. Data which correspond to the respective Contemporary infrastructure ontology, relations, attributes and rules for use. Other This way all these ontological and functional as- Internet users will have access to the geo- pects of the system will conceptually define graphic location and the basic functionality of every registered event. work with geographic data. The project will build Part of the activities included in the project up over the old version of the archaeological address the creation of a Geographic Informa- map of Bulgaria (AMB). The system will be cre- tion System (GIS) that exhibits better function- ated as an update of the outdated software ality in internet: easy access, registration of new from the late 90-s and add new types of infor- sites, updating of the information. An innovative mation, minimal content management capabilities, internet application will allow registration of data standard GIS functionality and architecture es- from a distance combined with regulated access pecially designed to encompass new features for the end-users. An electronic form will be de- and data. The successor of the AMB is to be veloped for these purposes. A new approach for designed to support both online and offline de- data entry online will be proposed to users. All ployment over a single code base, including de- this will be accomplished through the use of the ployment as portable application (on a flash available server GIS2 in combination with the use memory stick for example). This will enable it to of open source products which will enable pub- provide both online access to the full database, lishing data online. Doubtlessly the integration of and offline usage by field researchers for data spatial data into a server based GIS will improve entry and limited data inquiries (depending on management of the database of archaeological the amount of data carried). By completing the sites/events and will optimize the time for elec- fully automated synchronization for the offline tronic presentation of the required information. and the online instances the IS will be able to All necessary information will be available at the serve all the needs for data registration and re- NIAM-BAS website. porting of researchers working in distant regions Using the digital data for the modelled terri- where access to the online application may be tory as an environment will enable each site in difficult or impossible. the future to be precisely positioned through the Tight integration with the existing own GIS use of GPS coordinates along with other sources server side software will enable the online ver- of information. Using digital data for the geo- sion to be extended to provide additional serv-
1 The system should be in line particularly with the requirements of the European INSPIRE directive 2 ESRI ArchGIS server, available at NIAM-BAS.
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database are regulated by the statement of the tion of each registered site. Ministry of Culture3. The importance of the AMB was acknowledged by the Parliament. The newly Methodological scheme of the prototype GIS accepted law for the Cultural Heritage4 regu- for identification and protection of the archaeo- lates the role of the AMB in the process of reg- logical heritage, provided below, gives a clear istration of all the information coming from sys- overview of the logic in accomplishing the pro- tematic archaeological surveys into a single da- posed activities (Fig. 2). tabase. It is pointed out that the AMB as a na- tional database has to be managed by the Expected outcomes NIAM-BAS, National Institute for Preservation of The results of the project implementation will Cultural Heritage and the Ministry of Culture. strengthen the inter-institutional links between The methods for the field survey, with respect the Sofia University and the NIAM-BAS and will to the ability of integration of data within the create favourable conditions for accomplishment archaeological GIS, have to solve the following of future interdisciplinary research in the field of problems: archaeology based on mutual geoinformation Update of the available information of the technologies. The expected outcomes will also database; benefit the transfer of knowledge between spe- Field visits to archaeological sites that aim cialists in different areas (geography, cartography, their precise localization and position verification GIS, archaeology, archaeometry, cultural anthropol- with the use of a GPS and mobile GIS; ogy, tourism, etc.) as well as between the partici- Boundaries of the sites with greater sur- pants, other interested institutions and the public. faces defined by GPS coordinates; The expected outcomes can be summarized Update of the state of the sites and monu- into five major groups, each with a real world ments registered in the database; application: Shortlist of recommendations for preserva- 1. Effective organization of archaeological in-
Fig. 2. Methodological scheme of the proposed prototype GIS - ArchGIS
3 Order 26, published in the State Newspaper, issue 34, 1996 4 Published in the State Newspaper from 13. 03. 2009
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EQUAL IN EUROPEAN RESEARCH AREA
BULGARIAN VIPs
Prof. STEFAN KOSTIANEV, MD, DSc
Pathophysiology Department, Medical University - Plovdiv 15A, Vassil Aprilov Blvd., 4000 Plovdiv, Bulgaria Phone/Fax: +359 32 602 593; E-mail: [email protected]
Rector of Medical ganizations. He is the chief editor of the highest University Plovdiv; ranked medical journal in Bulgaria - Folia Medica. author of more than Prof. Kostianev has participated in scientific and 160 articles in peer-re- educational projects financed by the European viewed journals, took Research Fund, Tempus, The World Bank, Bulgar- part in writing over 10 ian Ministry of Education, Youth and Science, textbooks, educational Medical University - Plovdiv and in many clinical supplementary text- investigations. books and mono- His scientific interests are in the area of func- graphs. tional pulmonary diagnostics, pediatric respiratory physiology, blood-gas analysis and acid-base bal- ance, functional diagnostics software develop- Prof. DMSc Stefan Stoilov Kostianev, was born ment, physiology and pathophysiology of exer- in 1952 in Sofia. He graduates in medicine summa cise and sleep. cum laude in 1979 from Higher Medical Institute, Prof. Kostianev has published more than 160 Plovdiv. In the same year he becomes assistant articles in peer-reviewed journals and took part professor in Pathophysiology Dept. at HMI, Plovdiv, in writing over 10 textbooks, educational supple- where he has been working since then. Prof. mentary textbooks and monographs, and in con- Kostianev defended successfully his PhD thesis in structing national guidelines. He has been cited 1987, became associated professor in 1996, acquired more than 500 times in foreign and Bulgarian DMSc in 2004 and became full professor in 2006. journals. In 1999 he was elected as Vice Dean of the Medi- Numerous MSc and PhD theses were success- cal Faculty. He is head of Pathophysiology Dept. at fully defended under his scientific guidance. At the same faculty since 2004 and was elected as present he is a PhD advisor of 5 PhD students. Rector of Medical University - Plovdiv in July 2011. Hobbies: chess, guitar, sport, aphoristics; Mem- He specialized in elite scientific centers and ber of the Union of Independent Bulgarian Writ- laboratories abroad. Prof. Kostianev has taken ers. part in the leadership of numerous scientific or-
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Prof. IVAN MINKOV, DSc
Department of Plant Physiology and Molecular Biology and Genomics Research Center, Plovdiv University Paisii Hilendarski Phone: +359 32 261 555, Fax: +359 32 629 495, E-mail: [email protected]
Head of the Depart- lecular Biology and Plant Biotechnology. Over the ment of Plant Physiol- course of this project he visited a number of ogy and Molecular Bi- European Universities and created numerous ology, and the working collaborations, many of which still exist Genomics Research today. Many young researchers have been edu- Centre (GRC). Author cated and have defended their own PhD theses of 12 books, a number over these collaborations. of research papers, Areas of teaching and research experi- and 8 monographic ence book chapters in in- The main areas of teaching and research are ternational editions. Molecular Basis of Plant Stress Response - Professor in the area of Plant Molecular Biol- oxidative Stress in Higher Plants, Chloroplast De- ogy, Ivan Minkov has been the head of the De- velopment and Chlorophyll Synthesis, Plant partment of Plant Physiology and Molecular Bi- Microspore Cultures, Regulation of Nitrate Re- ology, as well as the Genomics Research Centre duction in Higher Plants, DNA markers in the tax- (GRC), University of Plovdiv (UoP) for the last 22 onomy of parasitic plants, Plant Transformation, years. With 18 defended PhD students, he made viroid RNA-proteins interaction, Bioinformatics - a major contribution to Molecular Biology and microRNA in genes regulation. Bioinformatics research at the University. He is a Publications leading scientist at UoP with a high publication Prof. Minkov has published 12 books, a record and strong participation in European re- number of research papers, as well as 8 mono- search programs. Prof. Minkov is a member of graphic book chapters in international editions. the Program Committee and National Contact Around 40 research papers are in peer review Point for the Seventh Framework Program. international journals with a combined total im- Education and career pact factor of about 85 and more than 520 ci- Prof. Minkov was born in 1949 in Plovdiv. He tations. Prof. Minkov also holds two patents for graduated from the University of Plovdiv in 1972 biologically active compounds for nitrates regu- as a MA in General Biology. In 1977 he defended lation in plants. his PhD thesis at the University of Plovdiv in the Teaching and research projects area of Plant Physiology and Biochemistry of In the period of 1996-2000, Prof. Minkov su- resurrection plants with high drought tolerance. pervised five TEMPUS projects for enhancing the Later, he specialized in the area of Chlorophyll higher education in the field of Molecular Biol- Biosynthesis in higher plants at the University of ogy and Plant Biotechnology. He later partici- Gothenburg, Sweden for a total period of 2 years, pated as a local coordinator in 7 projects in and later at the Institute for Photobiology, Minsk, Framework Program 6 (FP6) and 4 projects in Belorussia. After that he defended his Doctor of FP7. Presently, Prof. Minkov is a coordinator of a Sciences degree in the same field and was pro- large FP7 REGPOT project for developing re- moted to full professorship at the University of search infrastructure in the area of Systems Bi- Plovdiv shortly thereafter, in 1996. ology. Under his guidance, the Department and After 1989, Prof. Minkov started work on a the GRC also took part in projects from NATO research infrastructure in the field of Plant Mo- scientific program and Swiss National Science
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Fund. He also coordinated a number of projects Awards from the National Science Fund - and especially Prof. Minkov was awarded with the Pythago- one large project aimed at establishing a Ge- ras Award for the largest research financing in nome Research Centre. the period 2008-2010, and the Regional Centre Prof. Minkov has initiated two Bachelor de- headed by him was distinguished with a plaque grees at the Faculty of Biology - Molecular Biol- from the Ministry of Education and Sciences as ogy and Bioinformatics - both as a concept and a center with the highest FP6 participation as a material science with human and teaching (2009). potential.
Prof. IVAN PETKOV, DSc
Department of Organic Chemistry, Faculty of Chemistry, University of Sofia St. Kliment Ohridski Phone: +359 2 8161 442, E-mail: [email protected] sofia.bg
Head of the Depart- nonlinear optics, photonics; applied photochem- ment of Organic che- istry - dosimeters, solar indicators, sensors, solar mistry at University of cells, photoprotectors; intelligent organic com- Sofia. Leading Univer- pounds. sity Research Centre Prof. Ivan Petkov has participated in many for Nanoscience and projects. Part of these projects is held in part- Knowledge-based Ma- nership with international organizations such as: terials. University of Sofia - Pharmachim: Photopro- tector COMBRENOL for the cosmetics; Bulgarian Science Fund: Plastic gamma Prof. Ivan Petkov received his MSc degree in dosimeters; Composite materials for application the Faculty of Chemistry at University of Sofia in in the HIGH-TECH: immobilization of organic 1973 and a PhD degree at the Department of components in nano- and subnano molecule Organic Chemistry, Faculty of Chemistry, Univer- sieves; sity of Sofia St. Kliment Ohridski. He defended MAGATE: Plastic gamma dosimeters for his doctoral thesis on the topic of On the pho- foods; toinduced prototropic and metallotropic tautom- Programme Copernicus: Sensors for chem- erism of â-dicarbonyl compounds, their istry, medicine, and biology; metaloderivatives and nitrogen-containing ana- ÑÅÀ (France): Photochromic polymer films logues in 1981. with nonlinear optical properties; Prof. Ivan Petkov defended his DSc thesis University of Sofia: Modification of inor- Photochemical behaviour of â-dicarbonyl com- ganic glasses with sensitive organic compounds; pounds and derivatives of benzotiazole in 2003. Leading University Research Centre for He is currently leading the Department of Or- Nanoscience and Knowledge-based Materials; ganic Chemistry at University of Sofia. His scien- International project SENSIT EUREKA. tific interests are in the fields of organic synthe- He has above 120 publications, 4 books, 5 pat- sis, organic photochemistry; photochemical prop- ents. erties of organic compounds, dyes in solution, Member of European Photochemical Associa- polymer films, monolayers on different surfaces; tion, Inter-American Photochemical Association; photochromism, electrochromism, termochromism, Member of the Scientific Board of International radiochromism of organic compounds, derivatives Journal of Photoenergy; Chair holder, UNESCO and polymer films; photoelectrochemistry; pho- Chair in Sustainable Development and Ecological tovoltaic cells and effects; organic materials for Awareness.
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He specialized at: Department of Organic lar Photophysic and Photochemistry; visiting re- Chemistry, University of Amsterdam, The Nether- searcher in Centre DEtudes de Saclay, Electron- lands; Guest Professor in the University of ics and Nuclear Instrumentation Department, Tokoshima, Japan; visiting researcher in Centre Group for Organic Devices, Paris, France; Guest DEtudes de Saclay, Electronics and Nuclear In- Professor in Laval University, Department of strumentation Department, Group for Organic Physics, Quebec, Canada; Guest Professor in Re- Devices, Paris, France; Guest Professor in Univer- search Institute of Electronics, Shizuoka University, sity of Bordeaux, France, Department of Molecu- Hamamatzu, Japan.
Assoc. Prof. NELLY GEORGIEVA, PhD
Department of Biotechnology, University of Chemical Technology and Metallurgy, Sofia Phone +359 2 8163307, E-mail: [email protected]
Leader of research many, Halle-Wittenberg, Germany. projects; author of Areas of scientific interest: bioremediation of more than 60 manu- waste water containing phenol products and scripts in international heavy metals; immobilization and entrapment of scientific journals, two cells; probiotic and microbial food supplement, patents and more biobleaching of flax fibers with enzymes. than 30 papers and Assoc. Prof. Nelly Georgieva delivered lecture published contribu- courses on Microbiology for bachelor and mas- tions to international ter degree students and also Microbiology, Bio- congresses. chemistry and Biotechnology products in Ger- man language. She is an author of more than 60 Nelly Georgieva is an Associate Professor at manuscripts in international scientific journals, the University of Chemical Technology and Met- 2 patents and more than 30 papers and pub- allurgy, Sofia, Department of Biotechnology. She lished contributions to international congresses. graduated from Sofia University Kliment Assoc. Prof. Nelly Georgieva is the leader of Ohridski, Faculty of Biology in 1987. In 1997 she projects sponsored by the National Science Re- presented PhD thesis on Selection of methio- search Fund, Ministry of Education and Science - nine-enriched analogue-resistant mutants of Tri- Investigation on covalently bound yeast Can- chosporon cutaneum at the Institute of Micro- dida for biotransformation of furfural - 1994 biology of the Bulgarian Academy of Science. and Synthesis and application of nanomaterials From 1997 till 1999 she made postgraduate fel- by biofilm formation for waste water treatment lowship sponsored by DAAD Agency of Ger- - 2010.
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Assoc. Prof. ZHECHKO DIMITROV, PhD
LB-Bulgaricum Plc. R&D Center, 12-A, Malashevska Str., 1000 Sofia, Bulgaria E-mail: [email protected]
Head of the Cen- ies, Zhechko Dimitrov introduces or develops meth- tre for Research and ods to evaluate the probiotic effects of LAB at Development at LB laboratory level, making it possible to undertake Bulgaricum. Author of studies on probiotic properties of hundreds and over 40 scientific pub- thousands of strains, and thus to select those lications in foreign strains that possess the most prominent properties. and Bulgarian scien- The next stage with selected strains with benefi- tific journals and 5 cial human health effects are clinical trials. projects with external Main subject of research of Zhechko Dimitrov financing. are probiotic properties of LAB, such as: effects to Zhechko Panayotov human immune system, anticholesterolic effects, Dimitrov was born in 1966 in Shumen. He gradu- properties of some bioactive peptides to decrease ated Master degree from the University of Food high blood pressure and to utilize calcium from the Technologies in Plovdiv and graduated as an engi- food, and others. After testing for probiotic prop- neer-technologist in the specialty Microbiological erties, including clinical trials, probiotic products are and fermentation processes in 1994. From Octo- developed on the base of the selected probiotic ber 1994 until now he works at the Center for bacteria. In the areas of molecular biology and Research and Development at the state company probiotic effects Zhechko Dimitrov is author of LB Bulgaricum Plc (LB). In 1996 he became a re- over 40 scientific publications in foreign and Bul- search associate in the specialty Instrumental garian scientific journals with a total impact factor Analysis and in 1997 he created laboratory In- over 18.5, 5 projects with external financing to to- strumental Analysis, covering chromatographic tal about 2.6 million Euro, and three patent appli- and electrophoretic analyses. In 1998 he specialized cations. Zhechko Dimitrov has 4 scientific publica- in the Central Research Institute of the Corpora- tions in Advances in Bulgarian sciences journal. tion Meiji Milk in Japan. Between 1999 and 2002 Since the beginning of 2011 Zhechko Dimitrov is he introduced in Bulgaria DNA-based methods for head of the Centre for Research and Development typing of microorganisms such as pulse electro- at LB Bulgaricum. Over the next few years under phoresis, AFLP and Denaturing gradient gel electro- the leadership of Dr. Zhechko Dimitrov LB phoresis. The first two methods make it possible to Bulgaricums Research Centre will focus its efforts reliably identify and distinguish microbial individu- to introduce new research areas of technological als (strains), which is impossible with conventional research and health properties of LAB, as well to microbiological methods. The third method allows conduct clinical trials to definitively prove the characterizing the bacterial communities without probiotic properties. An important focus will be the the use of cultivation of representatives of various development of new probiotic products. Since the bacterial species. In 2007 Zhechko Dimitrov ac- beginning of 2011 the development of four new quired educational and scientific degree Doctor probiotic products containing specially selected in Molecular Biology at Bulgarian Academy of Sci- probiotic LAB was completed as a result of long ences - Institute of Molecular Biology. In the same research and innovation. Main types of the year he founded Laboratory Molecular Biology probiotic products will be: fresh dairy products with at LB. In 2009 he acquired the academic title of As- probiotics and prebiotics, dried products, cheeses sociated Professor in Bioactive substances at the fortified with bioactive peptides, drinks, capsules, etc. University of Food Technologies in Plovdiv. Much It is expected that the probiotic products devel- of the research work of Zhechko Dimitrov is aimed oped in LB Bulgaricum will be introduced on the at studying the health (probiotic) effects of lactic Bulgarian market in 2012 and from 2013 on foreign acid bacteria (LAB). In connection with these stud- markets.
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AWARDS
JOHN ATANASOFF AWARD FOR THE YEAR 2011
At an official ceremony in the beginning of ticipation are used in American companies October 2011 President Georgi Parvanov for the TrialPay Inc. and the Bank of America. Method ninth time bestowed John Atanasoff Award for decreasing the quantity of machine memory for achievements in the development of infor- necessary for self-education offered in his arti- mation society. The award is bearing the name of cle in 2008 has been approved and used by Ya- John Atanasoff - renowned scientist of Bulgar- hoo! Inc. ian origin and creator of the first digital elec- Diploma for applied projects and develop- tronic computer in the world. ments in the field of electronic management The award was established by President and information society in Bulgaria in 2011 Georgi Parvanov in 2003. It is adjudged every was adjudged for the second time. The Head of year to a young Bulgarian with considerable con- State handed it to Haralambi Haralambiev. He tribution to the development of computer and was born in 1985 and in 2009 graduated from information technologies and information society Sofia University St. Kliment Ohridski, faculty of in Bulgaria. mathematics and informatics, with bachelor de- The carrier of the John Atanasoff award for gree in discrete and algebraic structures. He has 2011 is Dr. Kuzman Ganchev. He was born in So- a number of national and international insignias fia in 1981. He graduated from Swarthmore College of honour in the field of informatics and com- - Pennsylvania with bachelor degree in computer puter sciences. In the recent years he heads the sciences, and was distinguished by special award applied research and development centre at for high performance. He got his MA from Univer- Musala Soft Company. Within the centre he is sity of Pennsylvania, where in 2010 he successfully responsible for 4 innovative projects having con- defended his PhD thesis in the field of machine tribution to the development of definite aspects learning with application of computer linguistics, on of information technologies at national and in- which he worked for several years. ternational level. Owing to his energetic activity In 2008/2009 he was a visiting fellow at the Musala SOFT Company received Pythagoras Institute for Parallel Processing of Information at award of the Ministry of Education, Youth and the Bulgarian Academy of Sciences. He con- Science for successful cooperation with scientific ducted a course in linear modules in machine and public organizations for 2010. learning for Masters program in artificial intelli- The Head of State also handed John gence at the Faculty of Mathematics and Atanasoff award for schoolchildren. This Informatics of Sofia University. year it was adjudged to Rumen Hristov, born in Since autumn 2010 he works for Google. 1993, a student at Nancho Popovich High He has publications in prestigious journals and School of Natural Sciences and Mathematics in was involved as a reviewer for authoritative pub- the city of Shumen. Among the distinctions he lications, as well as in the international confer- has won there are: the 2007 award of the city ence Recent Advances in Natural Language of Shumen for the student of the year in the Processing held in Bulgaria in September 2009. field of natural and mathematical sciences, He is the author of a software package for golden insignia for contribution to the youth in- machine learning which at present is used by the novation and information society; gold medal at Ontotext joint-stock company, Sofia for analysis the International Olympiad in mathematics in of biomedical texts. Other approaches and con- Thailand, gold medal at the International crete systems developed by him or with his par- Zhautikov Olympiad in mathematics, physics and
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informatics in the city of Almati, Kazakhstan, gold In his speech during the ceremony the Head medal and second place in the final ranking at of State expressed his content for validation of the International Olympiad in informatics in the initiative as a serious moral stimulus for Canada; gold medals at the Youth Balkan Olym- young people who dedicated themselves to sci- piad in informatics in Shumen, Belgrade and entific and applied research in the field of com- Bistritza (Romania), where he had highest score puter technologies, as well as for commitment to in the final ranking; silver medal at the Interna- it by Bulgarian universities, BAS, state institutions tional Olympiad in informatics in Cairo. He is and business. John Atanasoff award for schoolchildren win- ner for 2008 and 2009.
AWARDED WORKS AND SCIENTISTS IN THE COMPETITION FOR HIGH SCIENTIFIC ACHIEVEMENTS BY THE UNION OF SCIENTISTS IN BULGARIA IN 2011 FOR RESEARCH ACHIEVEMENTS IN DISSER- University St. Kl. Ohridski for his monograph TATION WORKS DEFENDED IN 2010 BY Founders of the Pchelin Church and an essay RESEARCHERS AGED UPTO 35 YEARS Spiritual Aspects of the Christian Art. Diploma for Research Achievements and Diploma Cash Prize Chief Assist. VIOLETA VALCHEVA RUSEVA, Dr. RAZVIGOR BORISLAVOV DARLENSKI PhD from the Institute of Microbiology at BAS from Tokuda Hospital for his dissertation Clini- for five articles in international journals in the cal-experimental Investigations on the Role of field of infectious microbiology Epidermal Barrier at Contact Skin Hypersensitiv- Assoc. Prof. NATALIYA DANAILOVA ity and Irritation. NIKOLOVA, PhD from Nikola Vaptzarov Naval Diploma for Research Achievements Academy - Varna, for 8 publications in the field KIRIL STOYANOV SHTEREV, PhD from the of qualitative analysis of solutions and of simu- Institute of Mechanics at BAS for his thesis Dig- lation modeling, published in prestigious refer- ital Modeling of Micro-flows of Compressible, enced international journals. Viscous, Heat-conducting Gas. FOR HIGH RESEARCH ACHIEVEMENTS OF SHAZIE YUMER YUSEIN-MYASHKOVA, PhD SCIENTISTS, MEMBERS OF THE UNION, from the Institute of Molecular Biology of BAS OVER 35 YEARS OLD for her dissertation Molecular-genetic Charac- teristics of hcIB Gene Coding the Histamine Diploma and Cash Prize Receptor in Drosophila. Prof. ZDRAVKO IVANOV LALCHEV, DSc YULIA RUSLANOVA ROMANOVA, PhD Head of Department at Sofia University St. Kl. from the Chair of Physical Chemistry at the Fac- Ohridski Faculty of Biology - for his monograph ulty of Chemistry of Sofia University St. Kl. Alveolar Surfactant and Neonatal Respiratory Ohridski for her dissertation Influence of the Distress Syndrome. Physiological Aspects and Environment on Geometry, Electronic Structure Modern Treatment and 32 scientific publications, and Magnetism of Polyaniline. from which 18 in journals with impact factor, connected with development and application of FOR HIGH RESEARCH ACHIEVEMENTS OF model systems in therapy of some types of pul- YOUNG SCIENTISTS, MEMBERS OF THE monary pathologies. UNION, UPTO 35 YEARS OLD Prof. ILZA KONSTANTINOVA PAZHEVA, DSc Diploma and Cash Prize from the Institute of Biophysics and Biophysical Theologian BLAGOVEST BLAGOEV VAR- Engineering of BAS - for 16 works in the field of BAKOV from the Faculty of Theology of Sofia computer-assisted research of the transport P-
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NACID IS HONORED WITH DIPLOMA FOR SUCCESSFULLY REALIZED PROJECT ON THE OPERATIONAL PROGRAM ADMINISTRATIVE CAPACITY
At the official ceremony in the Museum of consideration of applications, not exceeding 2 Archeology on November 29, 2011 National months; Centre for Information and Documentation Access to public information from the reg- (NACID) was honored with a Diploma for suc- ister of issued certificates and register of refus- cessfully realized project on the Operative Pro- als; gram Administrative Capacity. The project Electronic filing of documents for academic Optimization, integration and introduction of recognition of diplomas and possibility of getting electronic management of administrative and the certificate electronically; information services on acknowledgement of Monitoring on the Internet of the process diplomas for higher education and professional of processing of the filed documents by every qualifications obtained in the countries from the applicant - the course of consideration of the European region and third countries is one of application, the stage of the procedure, the deci- the six projects distinguished by the Managing sion taken on the application; Body. It was presented as a good practice at the Simplified checking of the academic status annual information event OPAK - main instru- of a foreign higher educational institution and le- ment for implementation of administrative re- gitimacy of the proposed by it education before form and electronic management. What we its final choice; have achieved, what we are proud of. Checking of the academic and qualification The project was realized during the period of status of candidates for the job in the relevant June 2009 - March 2011, and unquestionable organization on the part of employers; benefits for the citizens and business are: Access to current information on the new Accelerated administrative service on ac- site of NACID on procedures of acknowledge- knowledgement through a shortened time for ment in Bulgaria and abroad.
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ARTICLES RECENT PUBLICATIONS OF BULGARIAN SCIENTISTS
Title:Investigation of critical safety function Heat sink at low power and cold condition for Kozloduy Nuclear Power Plant WWER-1000/V320 Authors: Andreeva, M. , Pavlova, M. P., Groudev, P. P. Source: Annals of Nuclear Energy, In Press Available online (15 Nov. 2011) Author Affiliations: Institute for Nuclear Research and Nuclear Energy, 72, Tzarigradsko Shaussee Blvd. 72, 1784 Sofia, Bulgaria
ISSN: 0306-4549
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ Title:CFAR BI detector for mariner targets in time domain for bistatic forward scattering radar Authors: Kabakchiev, Chr.1, Garvanov, I.2, Cherniakov, M.3, Gashinova, M.3, Kabakchiev, A.4, Kiovtorov, V.4, Vladimirova, M.4, Daskalov, P.4 Source: Proceedings of SPIE - The International Society for Optical Engineering, Vol. 8008, (2011), Article number 80081U Author Affiliations: 1Faculty of Mathematics and Informatics, Sofia University St. Kliment Ohridski, Bulgaria; 2State University of Library Studies and Information Technologies, Sofia, Bulgaria; 3School of Electrical, Electronic and Computer Engineering, University of Birmingham, United Kingdom; 4Institute of Information and Communication Technologies, BAS, Sofia, Bulgaria.
ISSN: 0277-786X
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ Title:Photoelectron transport ability of chloroplast thylakoid membranes treated with NO donor SNP: Changes in flash oxygen evolution and chlorophyll fluorescence Authors: Vladkova, Radka1, Dobrikova, Anelia G. 1, Singh, Ranjeet2, Misra, Amarendra N. 2, Apostolova, Emilia1 Source: Nitric Oxide, Vol. 24, 2, (15 Mar. 2011), 84-90 Author Affiliations: 1Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Science, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria; 2Department of Biosciences and Biotechnology, School of Biotechnology, Fakir Mohan University, Jnan Bigyan Vihar, Balasore 756020, India. ISSN: 1089-8603
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Title:What have years of health10 insurance reforms brought about in Bulgaria? Re-appraising the Health Insurance Act of 1998 Authors: Atanasova, Elka1,2, Pavlova, Milena2, Velickovski, Robert1,2, Nikov, Bogomil1,2, Moutafova, Emanuela1, Groot, Wim2,3 Source: Health Policy, Vol. 102, 2-3, (Oct. 2011), 263-269 Author Affiliations: 1Department of Health Economics and Management, Faculty of Public Health, Medical University - Varna, Varna, Bulgaria; 2Department of Health Organisation, Policy, and Economics, Faculty of Health, Medicine and Life Sciences, CAPHRI, Maastricht University Medical Center, Maastricht University, The Netherlands; 3Top Institute Evidence-Based Education Research (TIER), Maastricht University, The Netherlands.
ISSN: 0168-8510
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ Title:Geographical situation of radio and television transmitters in Bulgaria Authors: Stefanova, Tereza Angelova Source: Procedia - Social and Behavioural Sciences, Vol. 19, (2011), 81-89 Author Affiliations: New Bulgarian University, 21, Montevideo Str., 1618 Sofia, Bulgaria
ISSN: 1877-0428
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ Title:PIN33 Economic Impact of the Antiretroviral Pharmacotherapy on Cost and HIV/AIDS Control in Bulgaria Authors: Dimitrova, M.1, Manova, M.1, Yancheva, N.2, Tcherveniakova, T.3, Stefanova, M.2, Petrova, G.1 Source: Value in Health, Vol. 14, 7, (Nov. 2011), A271 Author Affiliations: 1Medical University Sofia, Faculty of Pharmacy, Sofia, Bulgaria; 2University Hospital for active treatment of infectious and parasitic diseases, Sofia, Bulgaria; 3Hospital for Infectious and Parasitic Diseases, Sofia, Bulgaria.
ISSN: 1098-3015
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ Title:Evaluation of mobile learning system Authors: Georgieva, Evgeniya S., Smrikarov, Angel S., Georgiev, Tsvetozar S. Source: Procedia Computer Science, Vol. 3, (2011), 632-637 Author Affiliations: University of Ruse, 8, Studentska Str., 7017 Ruse, Bulgaria
ISSN: 1877-0509
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ Title:Oxygen isotopic evidence of residence and migration in a Greek colonial population on the Black Sea Authors: Keenleyside, Anne1, Schwarcz, Henry P.2, Panayotova, Kristina3 Source: Journal of Archaeological Science, Vol. 38, 10, (Oct. 2011), 2658-2666 Author Affiliations: 1Department of Anthropology, DNA Building Block C, Rm 224, 2140 East Bank Drive, Trent University, Peterborough, Ontario, Canada K9J 7B8; 2School of Geography and Earth Sciences, General Science Building, Rm 302, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada; 3Institute of Archaeology, Saborna Str. 2, 1000 Sofia, Bulgaria. ISSN: 0305-4403
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Title:Comparison of calculation models for determination of the mesopause temperature using SATI images Authors: Atanassov, Atanas Marinov Source: Advances in Space Research, Vol. 47, 11, (1 Jun. 2011), 1990-1998 Author Affiliations: Solar-Terrestrial Influences Institute, BAS, Department in Stara Zagora, P.O. Box 73, Bulgaria
ISSN: 0273-1177
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ Title:Solvent extraction of rosmarinic acid from lemon balm and concentration of extracts by nanofiltration: Effect of plant pre-treatment by supercritical carbon dioxide Authors: Peev, G.1, Penchev, P.2, Peshev, D.1, Angelov, G.2 Source: Chemical Engineering Research and Design, Vol. 89, 11, (Nov. 2011), 2236-2243 Author Affiliations: 1Department of Chemical Engineering, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria; 2Institute of Chemical Engineering, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria.
ISSN: 0263-8762
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ Title:Three dimensional linear motion transformation in a higher order dimensional space Authors: Tsankov, Y. Ts.1, Kazakoff, Al. B.2 Source: Applied Mathematical Modelling, Vol. 35, 12, (Dec. 2011), 5714-5740 Author Affiliations: 1Faculty of Mathematics and Informatics, Sofia University St. Kliment Ohridski, Bulgaria; 2Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 4, 1113 Sofia, Bulgaria.
ISSN: 0307-904X
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ISSN: 0176-4276
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ Title:On the equationsN-wave and soliton interactions in two and three dimensions Authors: Gerdjikov, V. S.1, Ivanov, R. I.2, Kyuldjiev, A.V.1 Source: Wave Motion, Vol. 48, 8, (Dec. 2011), 791-804 Author Affiliations: 1Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria; 2School of Mathematical Sciences, Dublin Institute of Technology, Kevin Str., Dublin 8, Ireland. ISSN: 0165-2125
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Advances in Bulgarian Science
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Title:Differentiabili ty of solutions of impulsive differential equations with respect to the impulsive perturbations Authors: Dishlieva, K. G. Source: Nonlinear Analysis-Real World Applications, Vol. 12, 6, (Dec. 2011), 3541-3551 Author Affiliations: Technical University, Sofia, Bulgaria
ISSN: 1468-1218
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ISSN: 0921-5107
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ISSN: 0734-242X
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ Title:A new metaldetector cations based on the combinedfor effect of photoinduced electron transfer and a light harvesting system Authors: Grabchev, Ivo1; Bosch, Paula2; Staneva, Dessislava3 Source: Journal of Photochemistry and Photobiology A-Chemistry, Vol. 222, 1, (Jun. 2011), 288-292 Author Affiliations: 1Sofia University St. Kliment Ohridski, Fac Med, 1407 Sofia, Bulgaria; 2CSIC, Inst Polymer Sci & Technol, Dept Photochem, E-28006 Madrid, Spain; 3University of Chemical Technology and Metallurgy, 1758 Sofia, Bulgaria.
ISSN: 1010-6030
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ISSN: 0378-8741
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E v e n t s
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E V E N T S
EUROPEAN RESEARCHERS NIGHT 2011
European Researchers Night was held in Bul- was to direct public attention to different garia for the sixth consecutive year - annual spheres of science: physics and technologies event which is held on the same day in the whole (2006); archeology and history (2007); biology, Europe. It was realized with financial support of chemistry and ecology (2008); astronomy the European Commission on the 7-th Frame- (2009). In 2010 the accent was made on re- work Programme for research and technological searchers role in science and industry for tech- development, subprogram People. nological development in promotion of EU poli- European researchers night was held on cies for improving economic growth and quality September 23, 2011 simultaneously in the cities of life. Events organized during previous years of Sofia, Plovdiv, Varna, Ruse, Stara Zagora and were very successful and highly appreciated by Burgas with various events. the public, especially by young people who were In Bulgaria the project European Researchers given various possibilities for participation. Night 2011" - RECSES (RÅsearchers in Ñhemistry In the context of the International Year of Supporting Economy and Society), was realized by Chemistry European Researchers Night 2011 in a consortium with participants: Sofia University St. Bulgaria was conducted under the motto: Re- Kl. Ohridski (coordinator), Young Talents Club, searchers and chemistry in support of Technical University - Sofia, Thracian University - economy and society. The year 2011 was the Stara Zagora, Information and improving teachers centenary from adjudging the Nobel Prize in qualification department, Angel Kanchev Univer- chemistry to Marie Sklodowska-Curie - the first sity of Ruse, Plovdiv University Paisii Hilendarski, woman Nobel Prize laureate and the first scien- Education Centre - Varna, Burgas Free University tist honored twice by Nobel Prize, which was the and GIS-Transfer Centre Foundation. occasion to mark womens contribution to sci- European Researchers Night Program 2011 ence. was realized with support from a number of or- 2011 ã. marked the 100-th anniversary from ganizations on the national and local level, such creation of a model of the atom by Rutherford as Union of Scientists in Bulgaria, Bulgarian Acad- - a discovery that changed our idea of the struc- emy of Sciences, National Polytechnic Museum, ture of the environment and had great influence Obekti magazine, AzBuki newspaper, etc. over advances in different human activities and During previous years intention of the team over the development of economy and quality of life in modern society. START OF BULGARIAN-SWISS RESEARCH PROGRAM 2011 - 2016
On October 27, 2011 Mrs. Petya Evtimova - ment of the EU, supporting efforts in decrease Deputy Minister of Education, Youth and Science, of economic and social inequities within the en- and HE Mrs. Regina Escher - the ambassador of larged EU by means of measures mutually the Swiss Confederation, opened an Information agreed upon by the parties. Bulgaria is among Day to mark the start of the Bulgarian-Swiss the countries that get the support. One of the Research Program 2011 - 2016. chosen fields for cooperation with Bulgaria is Swiss Confederation takes part in enlarge- research activity. For this purpose Bulgarian-
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Advances in Bulgarian Science
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Swiss Research Program (BSRP) was created. problems in four subject areas: Swiss national research foundation and Re- ecology: forestry, agriculture, land manage- search Department at the Ministry of Education, ment, waste utilization; Youth and Science (MEYS) are national organi- social sciences: social and human inequality zations which are responsible for the entire man- and regional inequities; agement and administration of the program. medicine: design and simulation of medicines; They are responsible for guarantying proper re- engineering: innovative construction design, alization of the program in accordance with its methods and materials. aims, principles and procedures. Projects carried out under the research pro- Bulgarian-Swiss Research Program meets the gram aim at strengthening the research coopera- needs of the Bulgarian research community in tion between Bulgaria and Switzerland. Particu- better international integration and cooperation. lar tasks of the Bulgarian-Swiss research Pro- It will be realized by means of mobilization of gram for achieving the goal are: the research capacity in Switzerland and Bulgaria promoting integration of Bulgarian re- and supporting research cooperation by means searchers into international networks; of joint research projects and non-recourse fi- facilitation of knowledge and know-how nancing. The projects will give chance to Bulgar- exchange among scientists. ian researchers together with scientists from Duration of the projects is up to 3 years and Switzerland under the form of consortiums to the research will be carried out in the participat- perform research activities directed to particular ing research centers in both countries.
FIRST SOFIA FESTIVAL OF SCIENCE
Sofia Festival of Science - a place where researchers came to Sofia - the creators of the boundaries between culture and science do not Large Hadron Collider (particle accelerator) at exist - was held on May 11-15, 2011 in the Doc- CERN Institute and ideologists of the experi- tors Garden in Sofia. The event is a part of the ments in it - Lyn Evans and Jim Virdee. Dr. Spiros Cultural calendar of the capital. Katsinelis from Greece disclosed the science in Sofia Festival of Science is organized by the dreaming - what is a sleep, what we know and British Council and Democritus Forum under the what we do not know about dreams. Mark patronage of the Ministry of Education, Youth Lewney from the United Kingdom told about and Science in partnership with the capital mu- physics through his acoustic show Rock Guitar nicipality. in 11 Dimensions. Frank Burnet, First Professor in A festival uniting different interesting events, Science Communication in the UK, revealed an varied publics, young and recognized scientists entirely unexpected cause to go out with friends from the country and abroad is organized for the for a drink. Hristo Kolev and Bozhidar Stefanov first time in Bulgaria. It will be held annually and impressed with their show Chemical Illusionism. will become a part of the international network. Partners of the Sofia Festival of Science are: In the era of the increasingly fast-paced Sofia University St Kl. Ohridski, Forestry University, technological development and continuous sci- Bulgarian Academy of Sciences, Union of Scien- entific discoveries the mankind is facing unpar- tists in Bulgaria, Polish Cultural Institute - Sofia, alleled challenges, and more and more solutions Bea Solutions, Programata Journal, Obekti Journal, are in the hands of researchers. On the other Dunkin Donuts, Ciela Publishing House, Roi Pub- hand, human understanding of basic notions lishing House, Microsoft, Go Green Communica- from the field of science is both right and obli- tions. Media partners are: Bulgarian National Tel- gation of every member of the modern demo- evision, iNews, NetInfo, az-deteto.com, BBC Knowl- cratic society. edge journal, Osem Journal, Bulgarian Science For the opening of the festival many foreign journal and newspaper Az-Buki.
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