The Power of Crowding for the Origins of Life
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Chemistry Grade Level 10 Units 1-15
COPPELL ISD SUBJECT YEAR AT A GLANCE GRADE HEMISTRY UNITS C LEVEL 1-15 10 Program Transfer Goals ● Ask questions, recognize and define problems, and propose solutions. ● Safely and ethically collect, analyze, and evaluate appropriate data. ● Utilize, create, and analyze models to understand the world. ● Make valid claims and informed decisions based on scientific evidence. ● Effectively communicate scientific reasoning to a target audience. PACING 1st 9 Weeks 2nd 9 Weeks 3rd 9 Weeks 4th 9 Weeks Unit 1 Unit 2 Unit 3 Unit 4 Unit 5 Unit 6 Unit Unit Unit Unit Unit Unit Unit Unit Unit 7 8 9 10 11 12 13 14 15 1.5 wks 2 wks 1.5 wks 2 wks 3 wks 5.5 wks 1.5 2 2.5 2 wks 2 2 2 wks 1.5 1.5 wks wks wks wks wks wks wks Assurances for a Guaranteed and Viable Curriculum Adherence to this scope and sequence affords every member of the learning community clarity on the knowledge and skills on which each learner should demonstrate proficiency. In order to deliver a guaranteed and viable curriculum, our team commits to and ensures the following understandings: Shared Accountability: Responding -
Prebiological Evolution and the Metabolic Origins of Life
Prebiological Evolution and the Andrew J. Pratt* Metabolic Origins of Life University of Canterbury Keywords Abiogenesis, origin of life, metabolism, hydrothermal, iron Abstract The chemoton model of cells posits three subsystems: metabolism, compartmentalization, and information. A specific model for the prebiological evolution of a reproducing system with rudimentary versions of these three interdependent subsystems is presented. This is based on the initial emergence and reproduction of autocatalytic networks in hydrothermal microcompartments containing iron sulfide. The driving force for life was catalysis of the dissipation of the intrinsic redox gradient of the planet. The codependence of life on iron and phosphate provides chemical constraints on the ordering of prebiological evolution. The initial protometabolism was based on positive feedback loops associated with in situ carbon fixation in which the initial protometabolites modified the catalytic capacity and mobility of metal-based catalysts, especially iron-sulfur centers. A number of selection mechanisms, including catalytic efficiency and specificity, hydrolytic stability, and selective solubilization, are proposed as key determinants for autocatalytic reproduction exploited in protometabolic evolution. This evolutionary process led from autocatalytic networks within preexisting compartments to discrete, reproducing, mobile vesicular protocells with the capacity to use soluble sugar phosphates and hence the opportunity to develop nucleic acids. Fidelity of information transfer in the reproduction of these increasingly complex autocatalytic networks is a key selection pressure in prebiological evolution that eventually leads to the selection of nucleic acids as a digital information subsystem and hence the emergence of fully functional chemotons capable of Darwinian evolution. 1 Introduction: Chemoton Subsystems and Evolutionary Pathways Living cells are autocatalytic entities that harness redox energy via the selective catalysis of biochemical transformations. -
A Chemical Engineering Perspective on the Origins of Life
Processes 2015, 3, 309-338; doi:10.3390/pr3020309 processesOPEN ACCESS ISSN 2227-9717 www.mdpi.com/journal/processes Article A Chemical Engineering Perspective on the Origins of Life Martha A. Grover *, Christine Y. He, Ming-Chien Hsieh and Sheng-Sheng Yu School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Dr. NW, Atlanta, GA 30032, USA; E-Mails: [email protected] (C.Y.H.); [email protected] (M.-C.H.); [email protected] (S.-S.Y.) * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +1-404-894-2878 or +1-404-894-2866. Academic Editor: Michael Henson Received: 29 January 2015 / Accepted: 19 April 2015 / Published: 5 May 2015 Abstract: Atoms and molecules assemble into materials, with the material structure determining the properties and ultimate function. Human-made materials and systems have achieved great complexity, such as the integrated circuit and the modern airplane. However, they still do not rival the adaptivity and robustness of biological systems. Understanding the reaction and assembly of molecules on the early Earth is a scientific grand challenge, and also can elucidate the design principles underlying biological materials and systems. This research requires understanding of chemical reactions, thermodynamics, fluid mechanics, heat and mass transfer, optimization, and control. Thus, the discipline of chemical engineering can play a central role in advancing the field. In this paper, an overview of research in the origins field is given, with particular emphasis on the origin of biopolymers and the role of chemical engineering phenomena. A case study is presented to highlight the importance of the environment and its coupling to the chemistry. -
Atomic and Molecular Laser-Induced Breakdown Spectroscopy of Selected Pharmaceuticals
Article Atomic and Molecular Laser-Induced Breakdown Spectroscopy of Selected Pharmaceuticals Pravin Kumar Tiwari 1,2, Nilesh Kumar Rai 3, Rohit Kumar 3, Christian G. Parigger 4 and Awadhesh Kumar Rai 2,* 1 Institute for Plasma Research, Gandhinagar, Gujarat-382428, India 2 Laser Spectroscopy Research Laboratory, Department of Physics, University of Allahabad, Prayagraj-211002, India 3 CMP Degree College, Department of Physics, University of Allahabad, Pragyagraj-211002, India 4 Physics and Astronomy Department, University of Tennessee, University of Tennessee Space Institute, Center for Laser Applications, 411 B.H. Goethert Parkway, Tullahoma, TN 37388-9700, USA * Correspondence: [email protected]; Tel.: +91-532-2460993 Received: 10 June 2019; Accepted: 10 July 2019; Published: 19 July 2019 Abstract: Laser-induced breakdown spectroscopy (LIBS) of pharmaceutical drugs that contain paracetamol was investigated in air and argon atmospheres. The characteristic neutral and ionic spectral lines of various elements and molecular signatures of CN violet and C2 Swan band systems were observed. The relative hardness of all drug samples was measured as well. Principal component analysis, a multivariate method, was applied in the data analysis for demarcation purposes of the drug samples. The CN violet and C2 Swan spectral radiances were investigated for evaluation of a possible correlation of the chemical and molecular structures of the pharmaceuticals. Complementary Raman and Fourier-transform-infrared spectroscopies were used to record the molecular spectra of the drug samples. The application of the above techniques for drug screening are important for the identification and mitigation of drugs that contain additives that may cause adverse side-effects. Keywords: paracetamol; laser-induced breakdown spectroscopy; cyanide; carbon swan bands; principal component analysis; Raman spectroscopy; Fourier-transform-infrared spectroscopy 1. -
Prebiotic Chemistry: Geochemical Context and Reaction Screening
Life 2013, 3, 331-345; doi:10.3390/life3020331 OPEN ACCESS life ISSN 2075-1729 www.mdpi.com/journal/life Article Prebiotic Chemistry: Geochemical Context and Reaction Screening Henderson James Cleaves II Earth Life Science Institute, Tokyo Institute of Technology, Institute for Advanced Study, Princeton, NJ 08540, USA; E-Mail: [email protected] Received: 12 April 2013; in revised form: 17 April 2013 / Accepted: 18 April 2013 / Published: 29 April 2013 Abstract: The origin of life on Earth is widely believed to have required the reactions of organic compounds and their self- and/or environmental organization. What those compounds were remains open to debate, as do the environment in and process or processes by which they became organized. Prebiotic chemistry is the systematic organized study of these phenomena. It is difficult to study poorly defined phenomena, and research has focused on producing compounds and structures familiar to contemporary biochemistry, which may or may not have been crucial for the origin of life. Given our ignorance, it may be instructive to explore the extreme regions of known and future investigations of prebiotic chemistry, where reactions fail, that will relate them to or exclude them from plausible environments where they could occur. Come critical parameters which most deserve investigation are discussed. Keywords: chemical evolution; prebiotic organic reactions-prebiotic reactions in the aqueous phase; prebiotic reactions in the solid state; energy sources on the primitive Earth; mineral catalysis 1. Introduction Prebiotic chemistry is the study of how organic compounds formed and self-organized for the origin of life on Earth and elsewhere [1]. -
4.2 Ionic Bonds Vocabulary: Ion – Polyatomic Ion – Ionic Bond – Ionic Compound – Chemical Formula – Subscript –
4.2 Ionic Bonds Vocabulary: Ion – Polyatomic ion – Ionic bond – Ionic compound – Chemical formula – Subscript – Crystal - An ion is an atom or group of atoms that has an electric charge. When a neutral atom loses a valence electron, it loses a negative charge. It becomes a positive ion. When a neutral atom gains an electron, it gains a negative charge and becomes a negative ion. Common Ions: Name Charge Symbol/Formula Lithium 1+ Li+ Sodium 1+ Na+ Potassium 1+ K+ Ammonium 1+ NH₄+ Calcium 2+ Ca²+ Magnesium 2+ Mg²+ Aluminum 3+ Al³+ Fluoride 1- F- Chloride 1- Cl- Iodide 1- I- Bicarbonate 1- HCO₃- Nitrate 1- NO₃- Oxide 2- O²- Sulfide 2- S²- Carbonate 2- CO₃²- Sulfate 2- SO₄²- Notice that some ions are made of several atoms. Ammonium is made of 1 nitrogen atom and 4 hydrogen atoms. Ions that are made of more than 1 atom are called polyatomic ions. Ionic bonds: When atoms that easily lose electrons react with atoms that easily gain electrons, valence electrons are transferred from one type to another. The transfer gives each type of atom a more stable arrangement of electrons. 1. Sodium has 1 valence electron. Chlorine has 7 valence electrons. 2. The valence electron of sodium is transferred to the chlorine atom. Both atoms become ions. Sodium atom becomes a positive ion (Na+) and chlorine becomes a negative ion (Cl-). 3. Oppositely charged particles attract, so the ions attract. An ionic bond is the attraction between 2 oppositely charged ions. The resulting compound is called an ionic compound. In an ionic compound, the total overall charge is zero because the total positive charges are equal to the total negative charges. -
Analysis of Multipolar Linear Paul Traps for Ion–Atom Ultracold Collision Experiments
atoms Article Analysis of Multipolar Linear Paul Traps for Ion–Atom Ultracold Collision Experiments M. Niranjan *, Anand Prakash and S. A. Rangwala * Raman Research Institute, C. V. Raman Avenue, Sadashivanagar, Bangalore 560080, India; [email protected] * Correspondence: [email protected] (M.N.); [email protected] (S.A.R.) Abstract: We evaluate the performance of multipole, linear Paul traps for the purpose of studying cold ion–atom collisions. A combination of numerical simulations and analysis based on the virial theorem is used to draw conclusions on the differences that result, by considering the trapping details of several multipole trap types. Starting with an analysis of how a low energy collision takes place between a fully compensated, ultracold trapped ion and an stationary atom, we show that a higher order multipole trap is, in principle, advantageous in terms of collisional heating. The virial analysis of multipole traps then follows, along with the computation of trapped ion trajectories in the quadrupole, hexapole, octopole and do-decapole radio frequency traps. A detailed analysis of the motion of trapped ions as a function of the amplitude, phase and stability of the ion’s motion is used to evaluate the experimental prospects for such traps. The present analysis has the virtue of providing definitive answers for the merits of the various configurations, using first principles. Keywords: ion trapping; ion–atom collisions; linear multipole traps; virial theorem Citation: Niranjan, M.; Prakash, A.; Rangwala, S.A. Analysis of Multipolar Linear Paul Traps for 1. Introduction Ion–Atom Ultracold Collision Linear multipole Paul trap configurations are emerging as a natural choice for a wide Experiments. -
Formose Reaction Controlled by a Copolymer of N,N-Dimethylacrylamide and 4-Vinylphenylboronic Acid
polymers Article Formose Reaction Controlled by a Copolymer of N,N-Dimethylacrylamide and 4-Vinylphenylboronic Acid Tomohiro Michitaka, Toru Imai and Akihito Hashidzume * ID Department of Macromolecular Science, Graduate School of Science, Osaka University, Osaka 560-0043, Japan; [email protected] (T.M.); [email protected] (T.I.) * Correspondence: [email protected]; Tel.: +81-6-6850-8174 Received: 8 October 2017; Accepted: 24 October 2017; Published: 25 October 2017 Abstract: The formose reaction is an oligomerization of formaldehyde under basic conditions, which produces a complicated mixture of monosaccharides and sugar alcohols. Selective formation of useful monosaccharides by the formose reaction has been an important challenge. In this study, we have investigated the formose reaction controlled by N,N-dimethylacrylamide/4-vinylphenylboronic acid copolymer (pDMA/VBA) and phenylboronic acid (PBA) because boronic acid compounds form esters with polyols, e.g., monosaccharides and sugar alcohols. We obtained time–conversion data in the presence of these boronic acid compounds, and characterized the products by liquid chromatography-mass spectroscopy and NMR measurements. pDMA/VBA and PBA decelerated the formose reaction because of the formation of boronic acid esters with products. It is noteworthy that the formose reaction in the presence of pDMA/VBA and PBA formed favorably six- and seven-carbon branched monosaccharides and sugar alcohols. Keywords: formose reaction; boronic acid compounds; N,N-dimethylacrylamide/4-vinylphenyl boronic acid copolymer; phenylboronic acid; monosaccharides; sugar alcohols 1. Introduction Carbohydrates are ubiquitous in our life and very important biological materials [1,2]. Carbohydrates can be divided into three categories based on their molecular weight; (1) low molecular weight saccharides, e.g., monosaccharides and disaccharides, (2) oligosaccharides, and (3) polysaccharides. -
Inferring Chemical Reaction Patterns Using Rule Composition in Graph Grammars Jakob L Andersen1,4, Christoph Flamm2*, Daniel Merkle1* and Peter F Stadler2,3,4,5,6,7
Andersen et al. Journal of Systems Chemistry 2013, 4:4 http://www.jsystchem.com/content/4/1/4 RESEARCH ARTICLE Open Access Inferring chemical reaction patterns using rule composition in graph grammars Jakob L Andersen1,4, Christoph Flamm2*, Daniel Merkle1* and Peter F Stadler2,3,4,5,6,7 Abstract Background: Modeling molecules as undirected graphs and chemical reactions as graph rewriting operations is a natural and convenient approach to modeling chemistry. Graph grammar rules are most naturally employed to model elementary reactions like merging, splitting, and isomerisation of molecules. It is often convenient, in particular in the analysis of larger systems, to summarize several subsequent reactions into a single composite chemical reaction. Results: We introduce a generic approach for composing graph grammar rules to define a chemically useful rule compositions. We iteratively apply these rule compositions to elementary transformations in order to automatically infer complex transformation patterns. As an application we automatically derive the overall reaction pattern of the Formose cycle, namely two carbonyl groups that can react with a bound glycolaldehyde to a second glycolaldehyde. Rule composition also can be used to study polymerization reactions as well as more complicated iterative reaction schemes. Terpenes and the polyketides, for instance, form two naturally occurring classes of compounds of utmost pharmaceutical interest that can be understood as “generalized polymers” consisting of five-carbon (isoprene) and two-carbon units, respectively. Conclusion: The framework of graph transformations provides a valuable set of tools to generate and investigate large networks of chemical networks. Within this formalism, rule composition is a canonical technique to obtain coarse-grained representations that reflect, in a natural way, “effective” reactions that are obtained by lumping together specific combinations of elementary reactions. -
Influence of Chirality on the Electromagnetic Wave Electrical and Computer Engineering
Influence of Chirality on the Electromagnetic Wave Propagation: Unbounded Media And Chirowaveguides Priyá Dilipa Gaunço Dessai Dissertation submitted to obtain the Master Degree in Electrical and Computer Engineering Jury President: Professor José Manuel Bioucas Dias Supervisor: Professor Carlos Manuel dos Reis Paiva Co- Supervisor: Professor António Luís da Silva Topa Member Professor Sérgio de Almeida Matos December 2011 Abstract When a chiral medium interacts with the polarization state of an electromag- netic plane wave and couples selectively with either the left or right circularly polarized component, we call this property the optical activity. Since the beginning of the 19th century, the study of complex materials has intensied, and the chiral and bi-isotropic (BI) media have generated one of the most interesting and challenging subjects in the electromagnetic research groups in terms of theoretical problems and potential applications. This dissertation addresses the theoretical interaction between waves and the chiral media. From the study of chiral structures it is possible to observe the eect of the polarization rotation, the propagation modes and the cuto frequencies. The reection and transmission coecients between a simple isotropic media (SIM) and chiral media are also analyzed, as well as the relation between the Brewster angle and the chiral parameter. The BI planar structures are also analyzed for a closed guide, the parallel-plate chirowaveguide, and for a semi-closed guide, the grounded chiroslab. From these structures -
Locally Enhanced and Tunable Optical Chirality in Helical Metamaterials
hv photonics Article Locally Enhanced and Tunable Optical Chirality in Helical Metamaterials Philipp Gutsche 1,*, Raquel Mäusle 1 and Sven Burger 1,2 1 Zuse Institute Berlin, Takustr. 7, 14195 Berlin, Germany; [email protected] (R.M.); [email protected] (S.B.) 2 JCMwave GmbH, Bolivarallee 22, 14050 Berlin, Germany * Correspondence: [email protected]; Tel.: +49-30-841-85-203 Received: 31 October 2016; Accepted: 18 November 2016; Published: 23 November 2016 Abstract: We report on a numerical study of optical chirality. Intertwined gold helices illuminated with plane waves concentrate right and left circularly polarized electromagnetic field energy to sub-wavelength regions. These spots of enhanced chirality can be smoothly shifted in position and magnitude by varying illumination parameters, allowing for the control of light-matter interactions on a nanometer scale. Keywords: metamaterials; optical chirality; computational nano-optics 1. Introduction Helical metamaterials strongly impact the optical response of incident circularly (CPL) and linearly polarized light. They serve as efficient circular polarizers [1] and are candidates for chiral near-field sources [2]. Both, advancement of fabrication techniques [3–5] and design which employs fundamental physical properties [6] have significantly increased the performance of these complex structures. Most experimental, numerical and theoretical studies focus on the far-field response of helical metamaterials. Nevertheless, near-field interaction of light and chiral matter is expected to be enhanced in chiral near-fields. Recently, the quantity of optical chirality has been introduced quantifying this phenomenon [7]. In the weak-coupling regime, the interplay of electromagnetic fields and chiral molecules, which are not superimposable with their mirror image, is directly proportional to this near-field measure [8]. -
Nitrogen-15 Magnetic Resonance Spectroscopy, I
VOL. 51, 1964 CHEMISTRY: LAMBERT, BINSCH, AND ROBERTS 735 11 Felsenfeld, G., G. Sandeen, and P. von Hippel, these PROCEEDINGS, 50, 644 (1963). 12Bollum, F. J., J. Cell. Comp. Physiol., 62 (Suppi. 1), 61 (1963); Von Borstel, R. C., D. M. Prescott, and F. J. Bollum, J. Cell Biol., 19, 72A (1963). 13 Huang, R. C., and J. Bonner, these PROCEEDINGS, 48, 216 (1962); Allfrey, V. G., V. C. Littau, and A. E. Mirsky, these PROCEEDINGS, 49, 414 (1963). 14 Baxill, G. W., and J. St. L. Philpot, Biochim. Biophys. Acta, 76, 223 (1963). NITROGEN-15 MAGNETIC RESONANCE SPECTROSCOPY, I. CHEMICAL SHIFTS* BY JOSEPH B. LAMBERT, GERHARD BINSCH, AND JOHN D. ROBERTS GATES AND CRELLIN LABORATORIES OF CHEMISTRY, t CALIFORNIA INSTITUTE OF TECHNOLOGY Communicated March 23, 1964 Except for the original determination' of nuclear moments, nitrogen magnetic resonance spectroscopy has been limited to the isotope of mass number 14. Al- though N14 is an abundant isotope, it possesses an electric quadrupole moment, which seriously broadens the resonances of nitrogen in all but the most sym- metrical of environments.2 Consequently, nitrogen n.m.r. spectroscopy has seen only limited use in the determination of organic structure. It might be expected that N15, which has a spin of 1/2 and no quadrupole moment, would be very useful, but the low natural abundance (0.36%) and the inherently low signal intensity (1.04 X 10-3 that of H' at constant field) have thus far precluded utilization of N15 in n.m.r. spectroscopy'3 Resonance signals from N'5 have now been obtained from a series of N"5-enriched (30-99%) compounds with a Varian model 4300B spectrometer operated at 6.08 Mc/sec and 14,100 gauss.