Relevant bibliographies by topics / Significant molecules

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Significant molecules'

Author: Grafiati
Published: 18 May 2024

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Journal articles on the topic "Significant molecules"

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Boldyreva, Yulia V., Ilya A. Lebedev, Ekaterina V. Zakharchuk, Javid F. Garaev, Sofia V. Adamchuk, and Arthur M. Smilyanin. "Oligopeptides as Biochemically Significant Molecules." Journal of Ural Medical Academic Science 18, no. 2 (2021): 138–46. http://dx.doi.org/10.22138/2500-0918-2021-18-2-138-146.

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Peptides are a class of organic substances consisting of two or more amino acid residues connected to each other by peptide bonds —C(O)NH—. Peptides were first mentioned in 1900 by the German organic chemist G. E. Fischer. He assumed that peptides consist of a chain of amino acids connected by a certain type of bond. In 1902, he was able to prove the presence of a peptide bond, and by 1905 he had developed a general method that allows synthesizing peptides in the laboratory. Friedrich Engels said the most succinctly about proteins: «Life is a way of existence of protein bodies...». It follows from this that if there are protein molecules, there is an organism’s life and, conversely, there are no proteins — the organism is not viable. Probably, this fact served as an incentive for further study of peptides. So, in the middle of the last century, an opinion appeared among scientists about a new class of chemically active substances-cytomedins (biologically active peptides, regulatory peptides, peptide bioregulators (PB)). These molecules will be discussed in this paper.
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van den Berg, C. M. G. "Voltammetry of of biological significant molecules." TrAC Trends in Analytical Chemistry 12, no. 7 (August 1993): x. http://dx.doi.org/10.1016/0165-9936(93)87011-l.

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Hilt, J. Zachary, and Mark E. Byrne. "Configurational biomimesis in drug delivery: molecular imprinting of biologically significant molecules." Advanced Drug Delivery Reviews 56, no. 11 (September 2004): 1599–620. http://dx.doi.org/10.1016/j.addr.2004.04.002.

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Pandey, Padmaker, Anamika Pandey, Shruti Singh, and Nikhil Kant Shukla. "Self Assembled Monolayers and Carbon Nanotubes: A Significant Tool’s for Modification of Electrode Surface." Sensor Letters 18, no. 9 (September 1, 2020): 669–85. http://dx.doi.org/10.1166/sl.2020.4280.

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A compromising and well-organized model system is needed for investigating the molecular behaviour of biomolecules as many transduction processes and biological recognition occur at biological surfaces. The application of techniques in interfacial surfaces like one molecule thick films has made a feasible and significant tool for modern scientific studies. Self Assembling Monolayers (SAMs) technology is a very useful means for producing monomolecular films of various biological molecules on different substrates. Carbon Nanotubes (CNTs) have length-to-diameter aspect ratio property which provides a large surface-to-volume ratio, making it an intensely capable material for biomolecular attachments. The incorporation of Carbon Nanotubes (CNTs) with biological systems forming functional assemblies has shown an explored area of research. Organo-sulfur mainly alkanethiol (CnH2n+1–SH) molecules get adsorbed onto CNTs. This phenomenon has grabbed a lot of attention because Self Assembling Monolayers (SAMs) of organo-sulfur compound acts as an example system for understanding important chemical, physical or biological processes.
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Uday, R. V. Sriram, Rajdip Misra, Annaram Harika, Sandip Dolui, Achintya Saha, Uttam Pal, V. Ravichandiran, and Nakul C. Maiti. "Dabrafenib, idelalisib and nintedanib act as significant allosteric modulator for dengue NS3 protease." PLOS ONE 16, no. 9 (September 10, 2021): e0257206. http://dx.doi.org/10.1371/journal.pone.0257206.

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Dengue virus (DENV) encodes a unique protease (NS3/NS2B) essential for its maturation and infectivity and, it has become a key target for anti-viral drug design to treat dengue and other flavivirus related infections. Present investigation established that some of the drug molecules currently used mainly in cancer treatment are susceptible to bind non-active site (allosteric site/ cavity) of the NS3 protease enzyme of dengue virus. Computational screening and molecular docking analysis found that dabrafenib, idelalisib and nintedanib can bind at the allosteric site of the enzyme. The binding of the molecules to the allosteric site found to be stabilized via pi-cation and hydrophobic interactions, hydrogen-bond formation and π-stacking interaction with the molecules. Several interacting residues of the enzyme were common in all the five serotypes. However, the interaction/stabilizing forces were not uniformly distributed; the π-stacking was dominated with DENV3 proteases, whereas, a charged/ionic interaction was the major force behind interaction with DENV2 type proteases. In the allosteric cavity of protease from DENV1, the residues Lys73, Lys74, Thr118, Glu120, Val123, Asn152 and Ala164 were involved in active interaction with the three molecules (dabrafenib, idelalisib and nintedanib). Molecular dynamics (MD) analysis further revealed that the molecules on binding to NS3 protease caused significant changes in structural fluctuation and gained enhanced stability. Most importantly, the binding of the molecules effectively perturbed the protein conformation. These changes in the protein conformation and dynamics could generate allosteric modulation and thus may attenuate/alter the NS3 protease functionality and mobility at the active site. Experimental studies may strengthen the notion whether the binding reduce/enhance the catalytic activity of the enzyme, however, it is beyond the scope of this study.
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S, Aravinth, Prakash Joshi, and Partha Pratim Mondal. "Detection of fortunate molecules induce particle resolution shift (PAR-shift) toward single-molecule limit in SMLM: A technique for resolving molecular clusters in cellular system." Review of Scientific Instruments 93, no. 9 (September 1, 2022): 093704. http://dx.doi.org/10.1063/5.0101009.

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Molecules capable of emitting a large number of photons (also known as fortunate molecules) are crucial for achieving a resolution close to single molecule limit (the actual size of a single molecule). We propose a long-exposure single molecule localization microscopy (leSMLM) technique that enables detection of fortunate molecules, which is based on the fact that detecting a relatively small subset of molecules with large photon emission increases its localization precision [Formula: see text]. Fortunate molecules have the ability to emit a large burst of photons over a prolonged time ([Formula: see text] average blinking lifetime). So, a long exposure time allows the time window necessary to detect these elite molecules. The technique involves the detection of fortunate molecules to generate enough statistics for a quality reconstruction of the target protein distribution in a cellular system. Studies show a significant PArticle Resolution Shift (PAR-shift) of about 6 and 11 nm toward single-molecule-limit (far from diffraction-limit) for an exposure time window of 60 and 90 ms, respectively. In addition, a significant decrease in the fraction of fortunate molecules (single molecules with small localization precision) is observed. Specifically, 8.33% and 3.43% molecules are found to emit in 30–60 ms and >60 ms, respectively, when compared to single molecule localization microscopy (SMLM). The long exposure has enabled better visualization of the Dendra2HA molecular cluster, resolving sub-clusters within a large cluster. Thus, the proposed technique leSMLM facilitates a better study of cluster formation in fixed samples. Overall, leSMLM technique offers a spatial resolution improvement of ~ 10 nm compared to traditional SMLM at the cost of marginally poor temporal resolution.
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Cheng, Yaming. "Analyze molecular interaction for mixture of argon and particles with different sizes." Theoretical and Natural Science 18, no. 1 (December 8, 2023): 30–37. http://dx.doi.org/10.54254/2753-8818/18/20230290.

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This article elaborates on molecular dynamics simulation, which is a technology that supports us in analyzing the structure and dynamics of materials and their properties at a microscopic level. In this article, the molecular dynamics simulation develops on Lennard-Jones potential. The simulation is based on the fundamental understanding between Argon-Argon molecules. The application for running molecular dynamics simulation is Moldy. The Argon particles size is changed by altering van der Waals radius from Lennard-Jones potential parameters, and the mixture of Argon and different sizes particles will be simulated by Moldy. The average potential energy is collected and compared. It discusses how the size of particles affect the average potential energy. Moreover, the trend of potential energy respects to timesteps for each molecule is depicted and compared graphicly by Gnuplot. It discusses how the potential energy changes according to timesteps for different sizes particles. In the end, the result is collected and summarized. It discovers that potential energy increases slowly when particles sizes increase, and the potential energy decreases significantly when particles sizes decrease. In addition, it founds out that molecules with different sizes have a noticeable change initially. Oddly, there is no observation of significant changes in the potential energy of the original molecule. Moreover, the initial decrease for molecules that increase in size is not as significant as that for molecules that decrease in size.
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ABADIR, G. B., K. WALUS, R. F. B. TURNER, and D. L. PULFREY. "BIOMOLECULAR SENSING USING CARBON NANOTUBES: A SIMULATION STUDY." International Journal of High Speed Electronics and Systems 18, no. 04 (December 2008): 879–87. http://dx.doi.org/10.1142/s0129156408005849.

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A simulation study using molecular dynamics and the density-functional-theory/non-equilibrium-Green's-function approach has been carried out to investigate the potential of carbon nanotubes (CNT) as molecular-scale biosensors. Single molecules of each of two amino acids (isoleucine and asparagine) were used as the target molecules in two separate simulations. The results show a significant suppression of the local density of states (LDOS) in both cases, with a distinct response for each molecule. This is promising for the prospect of CNT-based single-molecule sensors that might depend on the LDOS, e.g., devices that respond to changes in either conductance or electroluminescence.
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Chappell, Sarah, Carly Brooke, Richard J. Nichols, Laurence J. Kershaw Cook, Malcolm Halcrow, Jens Ulstrup, and Simon J. Higgins. "Evidence for a hopping mechanism in metal|single molecule|metal junctions involving conjugated metal–terpyridyl complexes; potential-dependent conductances of complexes [M(pyterpy)2]2+ (M = Co and Fe; pyterpy = 4′-(pyridin-4-yl)-2,2′:6′,2′′-terpyridine) in ionic liquid." Faraday Discussions 193 (2016): 113–31. http://dx.doi.org/10.1039/c6fd00080k.

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Extensive studies of various families of conjugated molecules in metal|molecule|metal junctions suggest that the mechanism of conductance is usually tunnelling for molecular lengths < ca. 4 nm, and that for longer molecules, coherence is lost as a hopping element becomes more significant. In this work we present evidence that, for a family of conjugated, redox-active metal complexes, hopping may be a significant factor for even the shortest molecule studied (ca. 1 nm between contact atoms). The length dependence of conductance for two series of such complexes which differ essentially in the number of conjugated 1,4-C6H4- rings in the structures has been studied, and it is found that the junction conductances vary linearly with molecular length, consistent with a hopping mechanism, whereas there is significant deviation from linearity in plots of log(conductance) vs. length that would be characteristic of tunnelling, and the slopes of the log(conductance)–length plots are much smaller than expected for an oligophenyl system. Moreover, the conductances of molecular junctions involving the redox–active molecules, [M(pyterpy)2]2+/3+ (M = Co, Fe) have been studied as a function of electrochemical potential in ionic liquid electrolyte, and the conductance–overpotential relationship is found to fit well with the Kuznetsov–Ulstrup relationship, which is essentially a hopping description.
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Medcraft, Chris, and Melanie Schnell. "A Comparative Study of Two Bicyclic Ethers, Eucalyptol and 1,4-Cineole, by Broadband Rotational Spectroscopy." Zeitschrift für Physikalische Chemie 230, no. 1 (January 28, 2016): 1–14. http://dx.doi.org/10.1515/zpch-2015-0643.

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AbstractThe rotational spectra of the two structurally related molecules, 1,4-cineole and 1,8-cineole (eucalyptol), were measured between 2–8.5 GHz with chirped pulse Fourier transform microwave spectroscopy. The structures of these two molecules only differ in the connectivity of an ether functional group. This results in a significant change in the three dimensional structure of the molecule and consequently large differences in the rotational spectra. Only one conformer of each molecule was detected in the molecular jet and no line splittings due to internal rotations were detected. A substitution structure (
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Dissertations / Theses on the topic "Significant molecules"

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Peppe, Salvatore. "Some unusual, astronomically significant organic molecules." Title page, contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09php4241.pdf.

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Appendix inside back cover. "June 2002" Bibliography: leaves 157-168. Experimental and theoretical studies were carried out on a number of unusual organic molecules of potential astronomical significance. The experimental work was corroborated by various theoretical approaches and by utilising computer-based quantum chemical calculations. Various covalently bound, anionic and neutral oxocarbon species were formed and studied. Additionally, two analogous heterocumulenic systems were investigated. Some isomers of either system, when energised, were shown to undergo gas-phase rearrangement processes.
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Morisawa, Yusuke. "Spectroscopic study of some chemically significant molecules in molecular clouds." 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/144599.

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Ray, Samapika. "Study to explore inclusion complexations and assorted interactions of some industrially and biologically significant molecules in diverse systems." Thesis, University of North Bengal, 2022. http://ir.nbu.ac.in/handle/123456789/4789.

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Barman, Siti. "Investigation on solvation behaviour and host guest inclusion complexes of some significant molecules with diverse cyclic compounds." Thesis, University of North Bengal, 2017. http://ir.nbu.ac.in/handle/123456789/2588.

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Dutta, Ashutosh. "Exploration of diversified interactions of some significant compounds prevalent in several environments by physicochemical contrivance." Thesis, University of North Bengal, 2018. http://ir.nbu.ac.in/handle/123456789/2787.

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Day, G. M., T. G. Cooper, A. Cruz-Cabeza, K. E. Hejczyk, H. L. Ammon, S. X. M. Boerrigter, J. S. Tan, et al. "Significant progress in predicting the crystal structures of small organic molecules ¿ a report on the fourth blind test." International Union of Crystallography, 2009. http://hdl.handle.net/10454/4748.

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We report on the organization and outcome of the fourth blind test of crystal structure prediction, an international collaborative project organized to evaluate the present state in computational methods of predicting the crystal structures of small organic molecules. There were 14 research groups which took part, using a variety of methods to generate and rank the most likely crystal structures for four target systems: three single-component crystal structures and a 1:1 cocrystal. Participants were challenged to predict the crystal structures of the four systems, given only their molecular diagrams, while the recently determined but as-yet unpublished crystal structures were withheld by an independent referee. Three predictions were allowed for each system. The results demonstrate a dramatic improvement in rates of success over previous blind tests; in total, there were 13 successful predictions and, for each of the four targets, at least two groups correctly predicted the observed crystal structure. The successes include one participating group who correctly predicted all four crystal structures as their first ranked choice, albeit at a considerable computational expense. The results reflect important improvements in modelling methods and suggest that, at least for the small and fairly rigid types of molecules included in this blind test, such calculations can be constructively applied to help understand crystallization and polymorphism of organic molecules.
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Campanher, Carlos Henrique. "A aprendizagem significativa crítica aplicada ao ensino da constante de Avogadro e o Mol." Universidade Federal do Pampa, 2016. http://dspace.unipampa.edu.br:8080/xmlui/handle/riu/1038.

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O presente trabalho foi elaborado com o objetivo de abordar o ensino da Constante de Avogadro e o número de moléculas, tendo como desafio, contextualizar o ensino da estequiometria, de uma forma que seja significativa. Partindo do princípio que o ensino através de metodologias tradicionais, com um alto número de aulas expositivas e com programas curriculares totalmente conteudistas, causam a desmotivação dos alunos. Estes são aspectos que tornam o processo de ensino - aprendizagem de Química menos interessante, desmotivando o aluno. Como uma proposta, que possa vir a contribuir com uma mudança de rota, a aprendizagem significativa crítica, apresenta-se como uma nova prática de ensino da estequiometria. Os procedimentos didáticos utilizados visam promover a reflexão sobre problemas contemporâneos do aluno e contribuir para a reflexão, do estudante no processo de ensino/aprendizagem da Química e a formação de um indivíduo crítico. A aplicação da proposta foi realizada com uma turma de 2º ano do Ensino Médio de uma escola da rede estadual de ensino, localizado no município de Santiago, no estado do Rio Grande do Sul, na Região Sul do Brasil, durante os meses de março, abril e maio de 2014. A investigação consistiu em efetivar uma prática considerada diferenciada para aquela realidade escolar que pudesse contribuir para a melhoria do ensino/aprendizagem de Química e para a eficácia de metodologias variadas através da elaboração de um material didático mediado pelo uso da pesquisa, com a construção de mapas conceituais, seminários, vídeos, aulas práticas não convencionais e a interlocução professor - aluno. Embasando esta proposta, a teoria da aprendizagem significativa e a teoria da aprendizagem significativa crítica de Ausubel e Moreira respectivamente. A análise da pesquisa foi feita a partir dos resultados obtidos com a aplicação destas metodologias em uma das turmas e sua comparação com os resultados obtidos em outra turma na qual não foram implementadas as metodologias. Os alunos que participaram desta proposta, mostraram um interesse maior na aprendizagem, obtendo um aproveitamento maior em relação a qualidade do material produzido. A aprendizagem de forma significativa crítica, trouxe uma vontade maior de aprender por parte do aluno do que a metodologia clássica.
This work was done in order to address the teaching of the Avogadro constant and the number of molecules, with the challenge to contextualize the teaching of stoichiometry, in a way that is meaningful. Assuming that teaching through traditional methods, with a high number of lectures and fully conteudistas curricula, cause demotivation of students. These are aspects make the teaching process - Chemistry learning less interesting, discouraging the student. As a proposal, which may contribute to a change of route, the significant critical learning, it presents itself as a new teaching practice stoichiometry. Didactic procedures used aim to promote reflection on contemporary student problems and contribute to the reflection, the student in the teaching / learning of chemistry and the formation of a critical individual. The implementation of the proposal was held with a group of 2nd year of high school a school state schools located in the city of Santiago, in the state of Rio Grande do Sul, in southern Brazil, during the months of March, April and May 2014. the investigation was to carry out a considered differentiated practice for that school reality that could contribute to the improvement of the teaching / learning of chemistry and the effectiveness of different methodologies by developing educational material mediated by the use of search with the construction of concept maps, seminars, videos, unconventional practical classes and teacher dialogue - student. Basing this proposal, the theory of meaningful learning and critical theory of meaningful learning of Ausubel and Moreira respectively. The analysis of the research was done from the results obtained from the application of these methodologies in one of the classes and their comparison with the results obtained in another class in which the methods were not implemented. Students, who participated in this proposal, have shown greater interest in learning, getting better use in relation to quality of material produced. Learning significant critically, brought a greater desire to learn from the student than the classical methodology.
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Muneer, Saiqa. "Novel nanoformulations and nanosensors for bioactive molecules of biomedical significance." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/213224/1/Saiqa_Muneer_Thesis.pdf.

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This thesis demonstrates novel nanosensors and nanomaterials for the sensitive detection of bioactive molecules (antibody therapeutics and antibiotics) in complex biological matrices utilizing thiol chemistry for label-free SERS detection. In addition to biomedical analysis, formulation development of dry powder inhalers overcomes the issues of adverse effects associated with parenteral or oral route of drug administration. It is expected to accomplish the key requisites like aerosolization properties, physicochemical characteristics, biocompatibility, and biodegradation with minimal side effects. Therefore, this study provided a motivation to address current advancement of detection techniques and development of novel drug delivery systems for the bioactive molecules.
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Tascilar, Metin. "Clinical significance of molecular markers in pancreatic cancer." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2002. http://dare.uva.nl/document/61858.

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ZHANG, XIN. "Surface functionalization of bioactive glasses with natural molecules of biological significance." Doctoral thesis, Politecnico di Torino, 2014. http://hdl.handle.net/11583/2535899.

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Natural or artificial materials used for replacement or supplement the functions of living tissues, termed as biomaterials, may be bioinert (i.e. alumina and zorconia,) resorbable (i.e. tricalcium phosphate), bioactive (i.e. hydroxyapatite, bioactive glasses, and glass-ceramics) or porous for tissue ingrowth (i.e. hydroxyapatite-coated metals). Among all the biomaterials, bioactive glass and glass-ceramics are widely used in orthopedic and dental applications and are being developed for tissue engineering. However, to a large extent, the behavior and overall performance of biomaterials are governed by surface properties. Surface modifications therefore provide unique possibilities to control the subsequent surface interaction and response which are required for particular application. By tailoring the material surface, a wide portfolio of additional functionalities is enabled to overcome material deficiencies while maintaining its bulk material properties. As a consequence, the surface functionalization of materials has become pivotal for academic research as well as industrial product development. Plant-derived polyphenols are compounds possessing one or more aromatic rings with one or more hydroxyl groups. They are broadly distributed in the plant kingdom and are the most abundant secondary metabolites of plants, with more than 8,000 phenolic structures currently known, ranging from simple molecules such as phenolic acids to highly polymerized substances such as tannins. Numerous researches and investigation reported the notable biological activities of polyphenol, such as cardiovascular protection, cancer prevention and treatment, antiaging activity as well as applications in Alzheimer’s disease, oral health, immune function diabetes and other neurodegenerative disorders. Till now, a number of previous investigations provide a number of surface functionalization techniques and make it possible to graft various kinds of biomolecules such as proteins, growth factors and enzymes to the surface of bioactive glass and glass-ceramics. However, very few researches have been focused on the coupling of natural bioactive polyphenols on surface of bioactive glass and glass-ceramics. As a conclusion, the aim of this thesis is to combine bioactive glasses and glass-ceramics with natural polyphenols, in this case they are grape polyphenol and tea polyphenol extracted from grape skin and green tea respectively, in order to make it possible to immobilize biomolecules as well as prepare smart biomaterials with both typical inorganic activity and specific biological benefits from natural molecule. This thesis can be divided into five chapters. The first chapter introduces the composition, chemical structure, biological properties and potential applications of plant polyphenols. In chapter II, the extraction methods and analysis techniques involved in polyphenol investigation are reviewed. Chapter III mainly illustrated the structure, property and biomedical application of biomaterials as well as methodologies and evaluation of surface functionalization. Materials and techniques related to this thesis are demonstrated in chapter IV. The last chapter, also the core chapter of this thesis, describes the results and discussions in five separate sections: i) surface functionalization of SCNA and CEL2 with gallic acid; ii) surface functionalization of SCNA and CEL2 with polyphenol extracted from grape skin; iii) surface functionalization of SCNA and CEL2 with polyphenol extracted from green tea; iv) surface functionalization of SC-45 with gallic acid and buffered gallic acid and v) surface functionalization of SC-45 with folic acid.
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Books on the topic "Significant molecules"

1

Smyth, W. Franklin. Voltammetric determination of molecules of biological significance. Chichester, West Sussex, England: New York, 1992.

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Doggett, Thad H. Menstruation: Origin and evolutionary significance. New York: Vantage Press, 1995.

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Jochen, Klein, Löffelholz Konrad, and International Cholinergic Symposium (9th : 1995 : Mainz, Rhineland-Palatinate, Germany), eds. Cholinergic mechanisms: From molecular biology to clinical significance. Amsterdam: Elsevier, 1996.

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Symposium on Mechanisms and Biological Significance of Pulsatile Hormone Secretion (1999 : London, England), ed. Mechanisms and biological significance of pulsatile hormone release. Chichester, West Sussex, England: Wiley, 2000.

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Z, Langer S., ed. Serotonin receptor subtypes: Pharmacological significance and clinical implications. Basel: Karger, 1992.

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Emel, Arinç, Schenkman John B, Hodgson Ernest 1932-, and NATO Advanced Study Institute on Molecular Aspects of Drug Metabolizing Enzymes (1993 : Kus̜adası, Turkey), eds. Molecular aspects of oxidative drug metabolizing enzymes: Their significance in environmental toxicology, chemical carcinogenesis, and health. Berlin: Springer-Verlag, 1995.

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NATO Advanced Study Institute on Molecular Aspects of Drug Metabolizing Enzymes (1993 Kuşadası, Turkey). Molecular aspects of oxidative drug metabolizing enzymes: Their significance in environmental toxicology, chemical carcinogenesis, and health. Berlin: Springer-Verlag,in cooperation with NATO Scientific Affairs Division, 1995.

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Cherdanceva, Tat'yana, Vladimir Klimechev, and Igor' Bobrov. Pathological and molecular biological analysis of renal cell carcinoma. Diagnosis and prognosis. ru: INFRA-M Academic Publishing LLC., 2020. http://dx.doi.org/10.12737/1020785.

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The monograph is devoted to the study of pathomorphological and molecular-biological characteristics of renal cell carcinoma and peritumoral zone depending on the degree of malignancy, and determine prognostic significance of criteria for predicting the postoperative survival of patients. Of interest to urologists, oncologists, pathologists, researchers, graduate students, dealing with the diagnosis of renal cell carcinoma and subsequent prediction of postoperative survival of patients.
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Puhal'skiy, Vitaliy. Introduction to Genetics. ru: INFRA-M Academic Publishing LLC., 2021. http://dx.doi.org/10.12737/1019851.

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The textbook outlines the cytological foundations of heredity, the regularities of Mendelian genetics, the chromosomal theory of heredity, the basics of molecular genetics and genetic engineering, the patterns of inheritance during distant hybridization, polyplodia and mutagenesis. Special attention is paid to the heterosis and genetics of populations. A significant part of the data is presented in the form of figures, diagrams, graphs and tables that facilitate the understanding of the material presented. Meets the requirements of the federal state educational standards of higher education of the latest generation. For students of higher educational institutions studying in agronomic specialties.
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European Symposium on Calcified Tissues (20th 1987 Sirmione, Italy). XX European Symposium on Calcified Tissues, Sirmione, Italy, October 4-8, 1987: Abstracts, including Satellite Workshop on Molecular and Cell Biology and Satellite Workshop on Biology and Regulation of Bone Metabolism : Clinical Significance. New York: Springer International, 1987.

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Book chapters on the topic "Significant molecules"

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Onaga, Geoffrey, and Kerstin Wydra. "Recent understanding on molecular mechanisms of plant abiotic stress response and tolerance." In Molecular breeding in wheat, maize and sorghum: strategies for improving abiotic stress tolerance and yield, 1–23. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789245431.0001.

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Abstract This chapter provides an overview of the recent significant perspectives on molecules involved in response and tolerance to drought and salinity, the 2 major abiotic stresses affecting crop production, and highlights major molecular components identified in major cereals.
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Wang, Joseph. "Adsorptive Stripping Voltammetric Studies of Biologically-Significant Compounds." In Redox Chemistry and Interfacial Behavior of Biological Molecules, 469–78. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4615-9534-2_35.

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Patriarche, G. J., J. M. Kauffmann, and J. C. Viré. "Modified Electrodes used to Elucidate Electrochemical Behaviors of Biologically Significant Molecules." In Redox Chemistry and Interfacial Behavior of Biological Molecules, 479–98. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4615-9534-2_36.

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Borcoman, Edith, and Christophe Le Tourneau. "Novel Immune Oncology Targets Beyond PD-1/PD-L1 in Head and Neck Cancer." In Critical Issues in Head and Neck Oncology, 51–61. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-23175-9_5.

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AbstractAnti-PD-1 immune checkpoint inhibitors have recently revolutionized the treatment of recurrent and/or metastatic head and neck squamous cell carcinoma (HNSCC) patients, both in the first and second recurrent and metastatic settings. However, not all patients respond to PD-1 blockade, nor derive prolonged benefit from these immunotherapies, requiring further development of immune-oncology strategies beyond PD-1/PD-L1 inhibitors. There has been an important therapeutic development with the evaluation of many new immune checkpoints molecules and other type of immunomodulatory molecules, along with combinations of these new agents with PD-1/PD-L1 inhibitors, but very few of these strategies have shown significant anti-tumor activity as single agent in HNSCC patients, and further results are awaited from ongoing trials. All randomized trials assessing novel immune-oncology drugs in combination with an anti-PD1/PD-L1 agents have failed so far in HNSCC patients. Many other immune-oncology drugs are still in early clinical development and will hopefully improve HNSCC patient outcomes.
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"Biologically Significant Molecules." In The Electron Capture Detector and the Study of Reactions with Thermal Electrons, 296–328. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2004. http://dx.doi.org/10.1002/0471659894.ch12.

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Mingos, D. M. P. "Band theory." In Essentials of Inorganic Chemistry 2. Oxford University Press, 1998. http://dx.doi.org/10.1093/hesc/9780198559184.003.0002.

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This chapter examines band theory, which extends the molecular orbital theory ideas which were developed for simple molecules to infinite solids. It is particularly useful for discussing the electrical conductivity and magnetic properties of compounds where the interactions between the individual components, be they atoms or molecules, are significant. The chapter then briefly reviews the basic concepts underlying a molecular orbital analysis of the bonding in a simple diatomic molecule derived from second row atoms. As the two atoms of the diatomic molecule which are initially a long distance apart are brought together, molecular orbitals which are delocalized over the whole molecule are generated by the overlap of symmetry-matching atomic orbitals. The chapter then looks at metallic radii and densities, doped semiconductors, graphite, photoconductivity, and transition metal oxides.
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Singh, Rohit, and Avneet Kaur. "Substituted Azoles as Non-Nucleoside Reverse Transcriptase Inhibitors Activity." In Strategies for the Synthesis of Heterocycles and Their Applications. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.110758.

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This Review article gives an overview of substituted azole based synthetic medicine and their significance application in treating various ailments. The chemical reactions of azoles with other heterocyclic compounds/chemical reagents produce a lot of new substituted molecules, which have plentiful biological actions and potential pharmaceutical applications. Azoles is considered a major class of heterocyclics and worldwide researchers have put great efforts in studying this nucleus in order to design and synthesize various new derived of imidazole and hybrid molecules with the identification of their significant role in many classes of drugs such as antiviral including anti-HIV. Azoles has inspiring molecular geometric structure that offers a suitable skeleton to build newer chemical entities which has encouraged medicinal chemists to design and synthesis of novel and effective molecule as potential therapeutic agents. However, there is an urgent need to study the mechanism of action at molecular level of several pharmacological actions resulting from azoles scaffold through modern methods to furnish safer and effective new molecules for the treatment of various diseases.
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Carney, S. L. "Proteoglycans." In Carbohydrate Analysis, 125–80. Oxford University PressOxford, 1994. http://dx.doi.org/10.1093/oso/9780199634491.003.0004.

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Abstract Proteoglycans, by definition, are conjugates of protein and glycosaminoglycan which are found largely in connective tissue. Their major role is to provide swelling pressure in these tissues by virtue of a Donnan osmotic effect due to the high fixed negative charge found on these molecules. Proteoglycans by their very nature are related to glycoproteins, but are generally differentiated from this class of molecule because of their distinct glycosaminoglycan component. In glycoproteins, generally the sugar moiety composes only a small percentage of the molecular mass, the sugars are relatively small, generally uncharged (with the exception of sialic acid residues), and frequently highly branched. In contrast, glycosaminoglycans from proteo glycan are large, linear molecules which are highly charged, containing both carboxylic acid and sulfate ester groups, and comprise generally a significant proportion of the total molecular mass.
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Atkins, Peter, George Ratcliffe, Mark Wormald, and Julio de Paula. "Vibrational spectroscopy." In Physical Chemistry for the Life Sciences. Oxford University Press, 2023. http://dx.doi.org/10.1093/hesc/9780198830108.003.0054.

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This chapter concerns vibrational spectroscopy. All molecules are capable of vibrating, and complicated molecules may do so in many different ways. The spectroscopic observation of the vibrations of molecules is used in this chapter to explore the stiffness of bonds and the rigidity of macromolecular structure. The core principles are explored by considering the single mode of vibration of a diatomic molecule, and then the principles are extended to the numerous modes of vibration of biochemically significant macromolecules. The chapter introduces techniques which have been developed specifically for the study of proteins and, by incorporating microscopes into the spectrometer, of sampling regions containing only a few molecules.
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Witten, T., and P. Pincus. "Surfactants." In Structured Fluids, 173–212. Oxford University PressOxford, 2004. http://dx.doi.org/10.1093/oso/9780198526889.003.0007.

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Abstract In the previous chapter we saw that the boundary of a liquid is responsible for significant, controllable forces—capillary forces. In this chapter we encounter an enormous expansion of that control through the use of “amphiphilic” molecules. An amphiphilic molecule contains a part that by itself would be soluble in the liquid and another part that would be insoluble in it. The insoluble parts have a more favorable free energy when they are away from the liquid; thus these molecules tend to concentrate at the liquid boundary. Because they influence surfaces and other boundaries, these molecules are called surfactants.
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Conference papers on the topic "Significant molecules"

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Barnes, M. D., W. B. Whitten, J. M. Ramsey, and S. Arnold. "Photophysics of Surfactant Molecules in Microdroplets." In Laser Applications to Chemical and Environmental Analysis. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/lacea.1996.lwb.6.

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Over the last several years, the study of fluorescence properties in both time and frequency domain of atoms in micron-sized optical cavities has held considerable interest in the physics and quantum optics communities. In addition to fascinating purely scientific aspects of the phenomenon of cavity quantum electrodynamics (QED), the ability to modify molecular fluorescence properties in a microcavity offers potentially significant sensitivity advantages for ultrasensitive - or, single molecule - fluorescence detection. For example, two important quantities which limit sensitivity in single molecule fluorescence detection - the saturated absorption rate and the integrated fluorescence yield - can be significantly increased by enhancing the fluorescence decay rate. We have shown previously that fluorescence decay rates1 as well as the integrated fluorescence yield2 of rhodamine 6G can be significantly enhanced in glycerol microdroplets. However, exploitation of these effects in order to gain sensitivity in single molecule fluorescence detection is nontrivial for at least two important reasons. First, the magnitude of decay rate enhancement depends on the position of the molecule within the droplet; molecules near the center of the droplet are not coupled to high Q resonances while molecules near the surface may strongly interact with cavity resonances associated with droplet. Thus, diffusion limits the amount of time a given molecule may interact with the resonances thereby limiting the fluorescence decay rate. Second, the fluorescence decay rate depends on the orientation of the transition moment with respect to the cavity "axis"; e.g., the surface normal for spherical cavities.
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Lermer, N., M. D. Barnes, C.-Y. Kung, W. B. Whitten, and J. M. Ramsey. "Detection of Single Molecules in Microcavities." In Laser Applications to Chemical and Environmental Analysis. Washington, D.C.: Optica Publishing Group, 1998. http://dx.doi.org/10.1364/lacea.1998.lma.3.

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A significant limitation in the detection and spectroscopy of individual dye molecules in liquid room temperature samples is the loss of fluorescence signal through chromophore photobleaching. Although often considered a fundamental restriction on sensitivity, it has been shown that the probability per excitation cycle of photobleaching may be reduced by enhancing the spontaneous emission rate of the chromophore located inside a microdroplet, which acts as a optical cavity. Studies of glycerol microdroplets containing R6G dye molecules, and levitated in a three-dimensional electrodynamic trap, have demonstrated a significant enhancement of both the fluorescence decay rate [1] and the total fluorescence yield [2] of the chromophore. Modification of the emission rate is greatest for molecules located near the surface of small (< 10 μm) microdroplets, where the influence of the droplet cavity modes of the droplet is most significant. To exploit this surface sensitivity, surfactant forms of rhodamine dyes were recently studied [3]. Fluorescence emission of the dye molecules, constrained to the droplet surface and with fixed transition moments perpendicular to the surface normal, were shown to be significantly enhanced at small droplet sizes. Additionally, at larger droplet sizes corresponding to higher droplet Q’s, preferential emission into the cavity modes was observed, however the detection of fluorescence photons was delayed by the storage time of the cavity, which may be on the same order as the fluorescence lifetime. These measurements, performed on relatively concentrated dye solutions, suggest that microcavity effects may be exploited to greatly enhance single molecule detection sensitivity in glycerol microdroplets. Furthermore, the large cavity storage time of the high-Q droplets opens the possibility for re-excitation of the molecule following emission into the droplet resonance, and subsequent stimulated emission, that is, single-molecule lasing.
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Xu, Dongyan, Deyu Li, and Yongsheng Leng. "Molecular Dynamics Simulations of Water and Ion Structures Near Charged Surfaces." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-42536.

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Extensive research has been devoted to nanofluidics in the past decade because of its potential applications in single molecule sensing and manipulations. Fundamental studies have attracted significant attention in this research field since the success of nanofluidic devices depends on a thorough understanding of the fluidic, ionic, and molecular behavior in highly confined nano-environments. In this paper, we report on molecular dynamics simulations of the effect of surface charge densities on the ion distribution and the water density profile close to a charged surface. We demonstrate that surface charges not only interact with mobile ions in the electrolyte, but also interact with water molecules due to their polarizability, and hence influence the orientation of water molecules in the near wall region. For the first time, we show that as the surface charge density increases, the water molecules within ∼ 5 Å of the {100} silicon surface will evolve from one layer into two layers. Meanwhile, the orientation of the water molecules is more aligned instead of randomly distributed. This layering effect may have important implications on electroosmotic flow through nanochannels and heat transfer across the solid-liquid interface.
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Costes, M., C. Naulin, N. Ghanem, and G. Dorthe. "Reactions between neutral species without a significant barrier: The C + NO and C+ N2O reactions." In The 50th international meeting of physical chemistry: Molecules and grains in space. AIP, 1994. http://dx.doi.org/10.1063/1.46566.

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Brewer, Bryson, Yandong Gao, and Deyu Li. "A Study of Small Molecule Absorption in Polydimethylsiloxane." In ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/mnhmt2012-75105.

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While polydimethylsiloxane (PDMS) has proven to be a popular material in the construction of microfluidic devices, the polymer network structure of PDMS makes it permeable to some molecules. This feature can be problematic for applications where thin PDMS walls are used to separate two different molecular streams or cell populations. Therefore, a better understanding of factors affecting small molecule absorption in PDMS is important for better design and operation of microfluidic devices. We report on studies of various factors in the absorption of fluorescent dyes in PDMS. Results show significant effects of thermal aging of PDMS on the absorption of the hydrophobic molecule Nile Red. In addition, the short-term hydrophobic recovery of the PDMS devices after being plasma bonded to a glass slide was investigated. Furthermore, we have tested the effects of aspiration and flushing, which show that the wetting property (hydrophilic or hydrophobic) of the flushing solvents can significantly affect the absorption of the Nile Red dye. Finally, parallel tests of PDMS absorption of fluorescein isothiocyanate (FITC) were conducted with no absorption observed.
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Cheng, L. T. "Organic Nonlinear Materials for Frequency Conversion: Property Trade-off and Recent Applications." In Compact Blue-Green Lasers. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/cbgl.1992.thd2.

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Frequency doubling of short wavelength diode lasers has significant technological applications in imaging and optical recording. One of the major hurdles towards achieving efficient doubling remains to develop highly nonlinear materials with appropriate linear optical properties such as birefringence and transparency. One approach is to engineer materials by doping or grafting nonlinear organic molecules into transparent polymeric matrixes. Second-order nonlinearity is obtained by the acentric alignment of these molecules along their dipole moments under an external electric field. With this approach, several molecular properties are important, including large molecular dipole moment and hyperpolarizability inner product (μβμ) as well as very low absorption at the first and second harmonic wavelengths of diode lasers (near 800 and 400 nm). An established guideline in identifying organic molecules with large hyperpolarizabilities is by the presence of low-lying strong charge-transfer (CT) electronic transitions. However, such an approach is in conflict with the requirement of transparency.
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Xu, Dongyan, Deyu Li, Yongsheng Leng, and Yunfei Chen. "Molecular Dynamics Simulation of Water and Ion Profiles Near Charged (100) and (111) Silicon Surfaces." In ASME 2008 First International Conference on Micro/Nanoscale Heat Transfer. ASMEDC, 2008. http://dx.doi.org/10.1115/mnht2008-52248.

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Fundamental studies in nanofluidics have attracted significant attention in the past decade since the success of nanofluidic devices depends on a thorough understanding of the fluidic, ionic, and molecular behaviors in highly confined nano-environments. In this work, molecular dynamics simulations of the effect of surface charge densities on the ion and water distribution in the near wall region has been performed for both (100) and (111) silicon surfaces. We demonstrate that surface charges not only interact with mobile ions in the electrolyte, but also interact with water molecules due to their polarizability and hence influence the orientation of water molecules close to the charged surface. It is shown that as the surface charge density increases, water molecules within ∼ 5 Å from the (100) silicon surface can evolve from one layer into two layers and meanwhile, the orientation of water molecules is more aligned instead of randomly distributed. However, no extra water layer is observed near a (111) silicon surface even under a surface charge density of as high as −0.2034 C/m2. The above phenomenon may be related to the different surface atom densities of (100) and (111) silicon surfaces.
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Kessler, Travis, Eric R. Sacia, Alexis T. Bell, and J. Hunter Mack. "Predicting the Cetane Number of Furanic Biofuel Candidates Using an Improved Artificial Neural Network Based on Molecular Structure." In ASME 2016 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/icef2016-9383.

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The next generation of alternative fuels is being investigated through advanced chemical and biological production techniques for the purpose of finding suitable replacements to diesel and gasoline while lowering production costs and increasing process yields. Chemical conversion of biomass to fuels provides a plethora of pathways with a variety of fuel molecules, both novel and traditional, which may be targeted. In the search for new fuels, an initial, intuition-driven evaluation of fuel compounds with desired properties is required. Due to the high cost and significant production time needed to synthesize these materials at a scale sufficient for exhaustive testing, a predictive model would allow chemists to preemptively screen fuel properties of potentially desirable fuel candidates. Recent work has shown that predictive models, in this case artificial neural networks (ANN’s) analyzing quantitative structure property relationships (QSPR’s), can predict the cetane number (CN) of a proposed fuel molecule with relatively small error. A fuel’s CN is a measure of its ignition quality, typically defined using prescribed ASTM standards and a cetane testing engine. Alternatively, the analogous derived cetane number (DCN), obtained using an Ignition Quality Tester (IQT), is a direct measurement alternative to the CN that uses an empirical inverse relationship to the ignition delay found in the constant volume combustion chamber apparatus. DCN data points acquired using an IQT were utilized for model validation and expansion of the experimental database used in this study. The present work improves on an existing model by optimizing the model architecture along with the key learning variables of the ANN and by making the model more generalizable to a wider variety of fuel candidate types, specifically the class of furans and furan derivatives, by including specific molecules for the model to incorporate. The new molecules considered include tetrahydrofuran, 2-methylfuran, 2-methyltetrahydrofuran, 5,5′-(furan-2-ylmethylene)bis(2-methylfuran), 5,5′-((tetrahydrofuran-2-yl)methylene)bis(2-methyltetrahydrofuran), tris(5-methylfuran-2-yl)methane, and tris(5-methyltetrahydrofuran-2-yl)methane. Model architecture adjustments improved the overall root-mean-squared error (RMSE) of the base database predictions by 5.54%. Additionally, through the targeted database expansion, it is shown that the predicted cetane number of the furan-based molecules improves on average by 49.21% (3.74 CN units) and significantly for a few of the individual molecules. This indicates that a selected subset of representative molecules can be used to extend the model’s predictive accuracy to new molecular classes. The approach, bolstered by the improvements presented in this paper, enables chemists to focus on promising molecules by eliminating less favorable candidates in relation to their ignition quality.
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Willey, K. F., V. Vorsa, and N. Winograd. "Molecular Photoionization and Chemical Imaging." In Laser Applications to Chemical and Environmental Analysis. Washington, D.C.: Optica Publishing Group, 1998. http://dx.doi.org/10.1364/lacea.1998.ltub.4.

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It is now possible to desorb a variety of organic molecules from surfaces using a tightly focused energetic ion beam. The molecules are detected as secondary ions using time-of-flight mass spectrometry, and may be spatially resolved by rastoring the ion beam over a larger area. A chemically resolved image is then acquired by examining the intensity of a particular mass as a function of x,y position. Presently, liquid metal ion sources using 25 KeV Ga+ ion projectiles can be focused to a spot of less than 20 nm in diameter. The limiting factor for molecule-specific imaging is sensitivity. The ion dose must be kept less than 1% of the total number of surface molecules to prevent chemical damage. Moreover, the ionization probability of desorbed molecules is generally less than 1 in 104. Since the molecules desorb from the first layer and since there are at most 4 × 106 molecules per square micron (depending on size of course), the signal rapidly approaches zero as the spatial resolution or beam probe size is reduced below 1 micron.1 Here we investigate the use of high intensity 100 fs laser pulses to photoionize the desorbed neutral molecules in an attempt to increase the measurement efficiency of this type of experiment. Our model system is dopamine, an important neurotransmitter that has aromatic character, but is subject to significant fragmentation using ns laser pulses. The results suggest that this approach can indeed expand the performance of mass-spectrometry based imaging experiments and can open new applications in bioimaging.
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Ivontsin, L. A., E. V. Mashkovtseva, and Y. R. Nartsissov. "STRUCTURAL PECULIARITIES OF THE FOF1 -ATP SYNTHASE PROTON HALF-CHANNELS IN MEMBRANES WITH DIFFERENT LIPID COMPOSITIONS." In X Международная конференция молодых ученых: биоинформатиков, биотехнологов, биофизиков, вирусологов и молекулярных биологов — 2023. Novosibirsk State University, 2023. http://dx.doi.org/10.25205/978-5-4437-1526-1-158.

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Molecular dynamics simulations were used to study the membrane lipid composition influence on the proton half-channels structure of Fo F1 -ATP synthase. A possible network of polar amino acid residues and water molecules, which have a significant effect on proton transport, were described. The effect of cardiolipins on the structural dynamics of amino acid side chains and protein hydration was evaluated.
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Reports on the topic "Significant molecules"

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Rizzo, T. R. Spectroscopic probes of vibrationally excited molecules at chemically significant energies. Office of Scientific and Technical Information (OSTI), April 1993. http://dx.doi.org/10.2172/6666734.

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Rizzo, T. R. Spectroscopic probes of vibrationally excited molecules at chemically significant energies. Office of Scientific and Technical Information (OSTI), March 1992. http://dx.doi.org/10.2172/5444957.

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Rizzo, T. R. Spectroscopic probes of vibrationally excited molecules at chemically significant energies. Progress report, August 15, 1991--August 14, 1992. Office of Scientific and Technical Information (OSTI), March 1992. http://dx.doi.org/10.2172/10134925.

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Rizzo, T. R. Spectroscopic probes of vibrationally excited molecules at chemically significant energies. Progress report, August 15, 1992--August 14, 1993. Office of Scientific and Technical Information (OSTI), April 1993. http://dx.doi.org/10.2172/10142638.

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Kapulnik, Yoram, and Donald A. Phillips. Isoflavonoid Regulation of Root Bacteria. United States Department of Agriculture, January 1996. http://dx.doi.org/10.32747/1996.7570561.bard.

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The overall objective of this project was to develop a conceptual framework for enhancing root colonization by beneficial bacteria. To accomplish this aim we tested the hypothesis that production and excretion of the plant phytoalexin medicarpin can be used for creation of a special niche along the legume roots, where beneficial microorganism, such as rhizobium, will have a selective advantage. On the Israeli side it was shown that higher medicarpin levels are exuded following the application of Rhizobium meliloti to the rhizosphere but the specific biochemical pathway governing medicarpin production was not induced significantly enough to support a constant production and excretion of this molecule to the rhizosphere. Furthermore, pathogenic bacteria and chemical elicitors were found to induce higher levels of this phytoalexin and it became important to test its natural abundance in field grown plants. On the US side, the occurrence of flavonoids and nucleosides in agricultural soils has been evaluated and biologically significant quantities of these molecules were identified. A more virulent Agrobacterium tumefaciens strain was isolated from alfalfa (Medicago sativa L.) which forms tumors on a wide range of plant species. This isolate contains genes that increase competitive colonization abilities on roots by reducing the accumulation of alfalfa isoflavonoids in the bacterial cells. Following gene tagging efforts the US lab found that mutation in the bacterial efflux pump operons of this isolate reduced its competitive abilities. This results support our original hypothesis that detoxification activity of isoflavenoids molecules, based on bacterial gene(s), is an important selection mechanism in the rhizosphere. In addition, we focused on biotin as a regulatory element in the rhizosphere to support growth of some rhizosphere microorganisms and designed a bacterial gene construct carrying the biotin-binding protein, streptavidin. Expressing this gene in tobacco roots did not affect the biotin level but its expression in alfalfa was lethal. In conclusion, the collaborative combination of basic and applied approaches toward the understanding of rhizosphere activity yielded new knowledge related to the colonization of roots by beneficial microorganisms in the presence of biological active molecules exuded from the plant roots.
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López-Valverde, Nansi, Javier Aragoneses, Antonio López-Valverde, Cinthia Rodríguez, and Juan Manuel Aragoneses. Role in the osseointegration of titanium dental implants, of bioactive surfaces based on biomolecules: A systematic review and meta-analysis of in vivo studies. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, June 2022. http://dx.doi.org/10.37766/inplasy2022.6.0076.

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Review question / Objective: Does the bioactive surface of titanium dental implants, based on biomolecules, influence osseointegration?. The aim of our study was to evaluate the role and efficacy of bioactive surfaces in osseointegration. Our review study limited the research interest to titanium dental implants coated with a biomolecule, i.e., an organic molecule produced by a living organism. Condition being studied: In recent years, much attention has been paid to topographical modifications of dental implant surfaces, as well as to their coating with biologically active substances.a bioactive surface is one capable of achieving faster and higher quality osseointegration, shortening waiting times and solving situations of poor bone quality. Molecules that can be applied for bioactive purposes include bioceramics, ions and biomolecules. Collagen and bone morphogenetic protein have been suggested as bone stimulating agents. Biofunctionalization of the implant surface with a biomimetic active peptide has also been shown to result in a significant increase in bone-to-implant ratios and an increase in peri-implant bone density.
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Gafni, Yedidya, and Vitaly Citovsky. Molecular interactions of TYLCV capsid protein during assembly of viral particles. United States Department of Agriculture, April 2007. http://dx.doi.org/10.32747/2007.7587233.bard.

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Tomato yellow leaf curl geminivirus (TYLCV) is a major pathogen of cultivated tomato, causing up to 100% crop loss in many parts of the world. The present proposal, a continuation of a BARD-funded project, expanded our understanding of the molecular mechanisms by which CP molecules, as well as its pre-coat partner V2, interact with each other (CP), with the viral genome, and with cellular proteins during assembly and movement of the infectious virions. Specifically, two major objectives were proposed: I. To study in detail the molecular interactions between CP molecules and between CP and ssDNA leading to assembly of infectious TYLCV virions. II. To study the roles of host cell factors in TYLCV assembly. Our research toward these goals has produced the following major achievements: • Characterization of the CP nuclear shuttling interactor, karyopherin alpha 1, its pattern of expression and the putative involvement of auxin in regulation of its expression. (#1 in our list of publication, Mizrachy, Dabush et al. 2004). • Identify a single amino acid in the capsid protein’s sequence that is critical for normal virus life-cycle. (#2 in our list of publications, Yaakov, Levy et al. in preparation). • Development of monoclonal antibodies with high specificity to the capsid protein of TYLCV. (#3 in our list of publications, Solmensky, Zrachya et al. in press). • Generation of Tomato plants resistant to TYLCV by expressing transgene coding for siRNA targeted at the TYLCV CP. (#4 in our list of publications, Zrachya, Kumar et al. in press). •These research findings provided significant insights into (i) the molecular interactions of TYLCV capsid protein with the host cell nuclear shuttling receptor, and (ii) the mechanism by which TYLCV V2 is involved in the silencing of PTGS and contributes to the virus pathogenicity effect. Furthermore, the obtained knowledge helped us to develop specific strategies to attenuate TYLCV infection, for example, by blocking viral entry into and/or exit out of the host cell nucleus via siRNA as we showed in our publication recently (# 4 in our list of publications). Finally, in addition to the study of TYLCV nuclear import and export, our research contributed to our understanding of general mechanisms for nucleocytoplasmic shuttling of proteins and nucleic acids in plant cells. Also integration for stable transformation of ssDNA mediated by our model pathogen Agrobacterium tumefaciens led to identification of plant specific proteins involved.
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Ron, Eliora, and Eugene Eugene Nester. Global functional genomics of plant cell transformation by agrobacterium. United States Department of Agriculture, March 2009. http://dx.doi.org/10.32747/2009.7695860.bard.

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The aim of this study was to carry out a global functional genomics analysis of plant cell transformation by Agrobacterium in order to define and characterize the physiology of Agrobacterium in the acidic environment of a wounded plant. We planed to study the proteome and transcriptome of Agrobacterium in response to a change in pH, from 7.2 to 5.5 and identify genes and circuits directly involved in this change. Bacteria-plant interactions involve a large number of global regulatory systems, which are essential for protection against new stressful conditions. The interaction of bacteria with their hosts has been previously studied by genetic-physiological methods. We wanted to make use of the new capabilities to study these interactions on a global scale, using transcription analysis (transcriptomics, microarrays) and proteomics (2D gel electrophoresis and mass spectrometry). The results provided extensive data on the functional genomics under conditions that partially mimic plant infection and – in addition - revealed some surprising and significant data. Thus, we identified the genes whose expression is modulated when Agrobacterium is grown under the acidic conditions found in the rhizosphere (pH 5.5), an essential environmental factor in Agrobacterium – plant interactions essential for induction of the virulence program by plant signal molecules. Among the 45 genes whose expression was significantly elevated, of special interest is the two-component chromosomally encoded system, ChvG/I which is involved in regulating acid inducible genes. A second exciting system under acid and ChvG/Icontrol is a secretion system for proteins, T6SS, encoded by 14 genes which appears to be important for Rhizobium leguminosarum nodule formation and nitrogen fixation and for virulence of Agrobacterium. The proteome analysis revealed that gamma aminobutyric acid (GABA), a metabolite secreted by wounded plants, induces the synthesis of an Agrobacterium lactonase which degrades the quorum sensing signal, N-acyl homoserine lactone (AHL), resulting in attenuation of virulence. In addition, through a transcriptomic analysis of Agrobacterium growing at the pH of the rhizosphere (pH=5.5), we demonstrated that salicylic acid (SA) a well-studied plant signal molecule important in plant defense, attenuates Agrobacterium virulence in two distinct ways - by down regulating the synthesis of the virulence (vir) genes required for the processing and transfer of the T-DNA and by inducing the same lactonase, which in turn degrades the AHL. Thus, GABA and SA with different molecular structures, induce the expression of these same genes. The identification of genes whose expression is modulated by conditions that mimic plant infection, as well as the identification of regulatory molecules that help control the early stages of infection, advance our understanding of this complex bacterial-plant interaction and has immediate potential applications to modify it. We expect that the data generated by our research will be used to develop novel strategies for the control of crown gall disease. Moreover, these results will also provide the basis for future biotechnological approaches that will use genetic manipulations to improve bacterial-plant interactions, leading to more efficient DNA transfer to recalcitrant plants and robust symbiosis. These advances will, in turn, contribute to plant protection by introducing genes for resistance against other bacteria, pests and environmental stress.
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9

Citovsky, Vitaly, and Yedidya Gafni. Viral and Host Cell Determinants of Nuclear Import and Export of the Tomato Yellow Leaf Curl Virus in Tomato Plants. United States Department of Agriculture, August 2002. http://dx.doi.org/10.32747/2002.7585200.bard.

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Tomato yellow leaf curl geminivirus (TYLCV) is a major pathogen of cultivated tomato, causing up to 100% crop loss in many parts of the world. In Israel, where TYLCV epidemics have been recorded since the 1960' s, this viral disease is well known and has been of economic significance ever since. In recent years, TYLCV outbreaks also occurred in the "New World" - Cuba, The Dominican Republic, and in the USA, in Florida, Georgia and Louisiana. Thus, TYLCV substantially hinders tomato growth throughout the world. Surprisingly, however, little is known about the molecular mechanisms of TYLCV interaction with the host tomato cells. The present proposal, a continuation of the project supported by BARD from 1994, expanded our understanding of the molecular mechanisms by which TYLCV enters the host cell nucleus for replication and transcription and exits it for the subsequent cell-to-cell spread. Our project sought two objectives: I. To study the roles of the viral capsid protein (CP) and host cell factors in TYLCV nuclear import. II. To study the roles of CP and host cell factors in TYLCV nuclear export. Our research toward these goals have produced the following major achievements: . Developed a one-hybrid assay for protein nuclear export and import (#3 in the List of Publications). . Identified a functional nuclear export signal (NES) in the capsid protein (CP) of TYLCV (#3 in the List of Publications). . Discovered homotypic interactions between intact TYLCV CP molecules and analyzed these interactions using deletion mutagenesis of TYLCV CP (#5 in the List of Publications). . Showed developmental and tissue-specific expression of the host factor required for nuclear import of TYLCV CP, tomato karyopherin alpha 1, in transgenic tomato plants (#14 in the List of Publications). . By analogy to nuclear import of TYLCV ,identified an Arabidopsis VIPI protein that participates in nuclear import of Agrobacterium T -complexes via the karyopherin alpha pathway (#4,6, and 8 in the List of Publications). These research findings provided significant insights into (i) the molecular pathway of TYLCV entry into the host cell nucleus, and (ii) the mechanism by which TYLCV is exported from the nucleus for the cell-to-cell spread of infection. Furthermore, the obtained knowledge will help to develop specific strategies to attenuate TYLCV infection, for example, by blocking viral entry into and/or exit out of the host cell nucleus. Also, as much of our findings is relevant to all geminiviruses, new anti- TYLCV approaches developed based on the results of our research will be useful to combat other members of the Geminivirus family. Finally, in addition to the study of TYLCV nuclear import and export, our research contributed to our understanding of general mechanisms for nucleocytoplasmic shuttling of proteins and nucleic acids in plant cells.
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10

Spiegel, Yitzhak, Michael McClure, Itzhak Kahane, and B. M. Zuckerman. Characterization of the Phytophagous Nematode Surface Coat to Provide New Strategies for Biocontrol. United States Department of Agriculture, November 1995. http://dx.doi.org/10.32747/1995.7613015.bard.

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Chemical composition and biological role of the surface coat (SC) of the root-knot nematodes, Meloidogyne spp. are described. SC proteins of M. incognita race 3 infective juveniles (J2) were characterized by electrophoresis and western blotting of extracts from radioiodine and biotin-labelled nematodes. J2 labelled with radioiodine and biotin released 125I and biotin-labelled molecules into water after 20 hours incubation, indicating that SC proteins may be loosely attached to the nematode. Antiserum to the principal protein reacted with the surface of live J2 and with surface proteins previously separated by electrophoresis. Human red blood cells (HRBC) adhered to J2 of several tylenchid nematodes over the entire nematode body. HRBC adhered also to nylon fibers coated with SC extracted from M. javanica J2; binding was Ca++/Mg++ dependent, and decreased when the nylon fibers were coated with bovine serum albumin, or pre-incubated with fucose and mannose. These experiments support a working hypothesis that RBC adhesion involves carbohydrate moieties of HRBC and carbohydrate-recognition domain(s) (CRD) distributed on the nematode surface. To our knowledge, this is the first report of a surface CRD i the phylum Nematoda. Gold-conjugated lectins and neoglycoproteins combined with silver enhancement have been used for the detection of carbohydrates and CRD, respectively, on the SC of M. javanica J2. Biotin reagents were used to trace surface proteins, specifically, on live J2. The labile and transitory nature of the SC was demonstrated by the dynamics of HRBC adherence to detergent-treated J2, J2 at different ages or fresh-hatched J2 held at various temperatures. SC recovery was demonstrated also by a SDS-PAGE profile. Monoclonal antibodies developed to a cuticular protein of M. incognita J2 gave a slight, but significant reduction in attachment of Pasteuria penetrans spores. Spore attachment as affected by several enzymes was inconsistent: alcian blue, which specifically blocks sulfyl groups, had no afffect on spore attachment. Treatment with cationized ferritin alone or catonized ferritin following monoclonal antibody caused significant decreases in spore attachment. Those results suggest a role in attachment by negatively charged groups.
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