Report of Contributions
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LASNPA & WONP-NURT 2017 Report of Contributions https://indico.cern.ch/e/635057 LASNPA & … / Report of Contributions Estimation of volumetric dose dist … Contribution ID: 6 Type: Parallel Talk Estimation of volumetric dose distribution delivery deviations from dose planned in 131I hyperthyroidism treatment: preliminary results During more than 60 years of Hyperthyroidism radioiodine treatment has been no general agree- ment on the applied dose or calculus methodology. The EANM Dosimetry Committee recommend in 2013 an “Standard Operational Procedures for Pre-Therapeutic Dosimetry (SOP)” based on the assessment of the individual 131I uptake and kinetics. To estimate the 3D dose delivery deviations from prescribed dose during patient specific application of this SOP, a computer Matlab application was developed and verified. It was design to execute: radiopharmaceutical curve fitting, cumulated activity calculations, functional thyroid mass estimation, obtain the therapeutic planning activity to warranty the prescribed dose and produce the 3D planning dose map and related dosimetry parameters. 6 patients with 150-400Gy prescribed dose data planning (average 241,67Gy) were analyzed using the developed application. The developed system was verify successfully using a test image phantom and 6 known pharmacokinetics data. The program fitting results were com- pared with Microcal (TM) Origin (version 6.0), showing not statistical differences (p <0.01). The tridimensional thyroid volume cumulated activity and dose distributions were heterogeneous. 3D dose distribution showed standard deviations between 20.41-108.3Gy (18.01-27.08% of prescribed dose). The differences between maximum and minimum dose value per voxel/MBq were 74-129%, corresponding to 112Gy and 495Gy respectively for the total dose administrated. According to the result, between 50,2% and 71,4% of patient’s thyroid will be treat with a dose of DP±20% of planned dose, the rest will be overdose or sub dose. Conclusions: the 3D treatment planning dose distribution were completely no-homogenous, the significant difference observed should be study in the future more deeply in order to optimizedthe hyperthyroidism iodine treatment. Index Terms: optimization, patient’s specific treatment, I-131, Hyperthyroidism Primary authors: LÓPEZ DÍAZ, Adlin (Nuclear Medicine Department, Hospital “Hermanos Amei- jeiras”, Havana, Cuba); MIGUEL MARTÍN, Juan (Nuclear Medicine Department, Hospital “Hermanos Ameijeiras”, Havana, Cuba); FERNÁNDEZ, Viviana (Nuclear Medicine Department, Hospital “Her- manos Ameijeiras”, Havana, Cuba); PÉREZ, Amalia (National University of “San Martín”, Buenos Aires, Argentine) Presenter: LÓPEZ DÍAZ, Adlin (Nuclear Medicine Department, Hospital “Hermanos Ameijeiras”, Havana, Cuba) Session Classification: Parallel Session - MP Track Classification: Medical Physics September 26, 2021 Page 1 LASNPA & … / Report of Contributions Determination of transmission fac … Contribution ID: 10 Type: Poster Determination of transmission factors for an 85Kr beta radiation beam using an extrapolation chamber The 85Kr isotope is a beta-ray emitter (gas) with a half-life of 10.76 years. It is produced inthe fission of Uranium and Plutonium. The sources of this isotope are the nuclear tests, thenuclear reactors and the reprocessing of nuclear fuel. In the gas release events around reactors, the 85Kr may represent a major hazard. In beta emitters, in order to evaluate the absorbed dose rate at different tissue depths, it is necessary to determine the transmission factors. In this work,the preliminary results of the determination of transmission factors of the 85Kr source of a BSS2 beta secondary standard are presented. For this purpose, an extrapolation chamber was used. The results obtained are considered acceptable, and they are within the uncertainties, in comparison with the values provided by the source calibration certificate (PTB, Germany). The maximum difference between the results determined in this work and those from the calibration certificate was 3.8%. Primary authors: Mrs ORAMAS POLO, Ivón (Instituto de Pesquisas Energéticas e Nucleares, CNEN, SP, Brazil.); Dr CALDAS, Linda (Instituto de Pesquisas Energéticas e Nucleares, CNEN, SP, Brazil.) Presenter: Mrs ORAMAS POLO, Ivón (Instituto de Pesquisas Energéticas e Nucleares, CNEN, SP, Brazil.) Session Classification: Poster Session - MP Track Classification: Medical Physics September 26, 2021 Page 2 LASNPA & … / Report of Contributions The LUCID-2 detector Contribution ID: 12 Type: Parallel Talk The LUCID-2 detector Tuesday, 24 October 2017 10:30 (30 minutes) The LUCID-2 detector is the main online and offline luminosity provider of the ATLAS experiment. It provides over 100 different luminosity measurements from different algorithms for each ofthe 2808 LHC bunches. LUCID was entirely redesigned in preparation for LHC Run 2: both the detec- tor and the electronics were upgraded in order to cope with the challenging conditions expected at the LHC center of mass energy of 13 TeV with only 25 ns bunch-spacing. While LUCID-1 used gas as a Cherenkov medium, the LUCID-2 detector is in a new unique way using the quartz windows of small photomultipliers as the Cherenkov medium. The main challenge for a luminometer isto keep the efficiency constant during years of data-taking. LUCID-2 is using an innovative calibra- tion system based on radioactive 207 Bi sources deposited on the quartz window of the readout photomultipliers. This makes it possible to accurately monitor and control the gain of thephoto- multipliers so that the detector efficiency can be kept stable at a percent level. A description of the detector and its readout electronics will be given, as well as preliminary results on the ATLAS luminosity measurement and related systematic uncertainties. Primary author: CABRAS, Grazia (Universita e INFN, Bologna (IT)) Presenter: CABRAS, Grazia (Universita e INFN, Bologna (IT)) Session Classification: Parallel Sessions - HEP Track Classification: High Energy Physics, Astrophysics and Cosmology (covering Hadron Structure, Phases of Nuclear Matter, QCD, Precision Measurements with Nuclei, Fundamental Interactions and Neutrinos) September 26, 2021 Page 3 LASNPA & … / Report of Contributions Molecular structures in slow nucle … Contribution ID: 13 Type: Plenary Talk Molecular structures in slow nuclear collisions Friday, 27 October 2017 09:00 (30 minutes) I will report on a quantitative study of the sub-Coulomb fusion of astrophysically important heavy- ion collisions, such as 16O + 16O and 12C + 12C. It is carried out using wave-packet dynamics. The low-energy collision is described in the rotating center-of-mass frame within a nuclear molecular picture [1]. A collective Hamiltonian drives the time propagation of the wave-packet through the collective potential-energy landscape that is calculated with a realistic two-center shell model [2- 4]. Among other preliminary results, the theoretical sub-Coulomb fusion resonances for 12C + 12C seem to correspond well with observations. The method appears to be useful for expanding the cross-section predictions towards stellar energies. 1. W. Greiner, J.Y. Park & W. Scheid, in Nuclear Molecules, World Scientific Pub, Singapore, 1995. 2. A. Diaz-Torres & W. Scheid, Nucl. Phys. A 757 (2005) 373. 3. A. Diaz-Torres, L.R. Gasques & M. Wiescher, Phys. Lett. B 652 (2007) 255. 4. A. Diaz-Torres, Phys. Rev. Lett. 101 (2008) 122501. Primary author: Dr DIAZ-TORRES, Alexis (University of Surrey, United Kingdom) Presenter: Dr DIAZ-TORRES, Alexis (University of Surrey, United Kingdom) Session Classification: Plenary Talks Track Classification: Nuclear Structure, Nuclear Reactions and Exotic Nuclei September 26, 2021 Page 4 LASNPA & … / Report of Contributions Development of clinically based pr … Contribution ID: 14 Type: Parallel Talk Development of clinically based prediction models using machine learning and Bayesian statistics The massive development of photon radiation treatment techniques as well as the increase useof Hadron therapy has led to a difficult treatment evaluation since many parameters are in play. At the same time, there has been an increase of cancer clinical data generation in the form of clinical records and imaging data. As a response, biophysical models based on clinical data mining and machine learning are increasingly being developed, with the aim of evaluating clinical effects of radiotherapy treatments. In this work, the framework for developing generic clinically based models is shown and illus- trated with Bayesian statistics neurologic grade prediction models in order to exemplify the type of models that can be developed from a mathematical point of view. The models are based on clin- ical records of patients who underwent radiotherapy treatment due to glioblastoma which is an aggressive brain cancer. A first model requires as a parameter the neurologic grade of the patient before the treatment then predicts the grade after the treatment. A second, enhanced, model was developed with the aim of making the prediction more realistic and it uses the neurologic grade before the treatment as well, but it additionally depends on the Clinical Target Volume (CTV). Furthermore, with the aid of Bayesian statistic we were able to estimate the uncertainty of the predictions. These models provide the guidelines for exploration of medical cancer data generated during treat- ments in order to determine which parameters play an important role in the outcome of clinical effects. Primary authors: