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Balasubramaniam, Dharini. "Extension polymorphism." Thesis, University of St Andrews, 1998. http://hdl.handle.net/10023/13495.
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Any system that models a real world application has to evolve to be consistent with its changing domain. Dealing with evolution in an effective manner is particularly important for those systems that may store large amounts of data such as databases and persistent languages. In persistent programming systems, one of the important issues in dealing with evolution is the specification of code that will continue to work in a type safe way despite changes to type definitions. Polymorphism is one mechanism which allows code to work over many types. Inclusion polymorphism is often said to be a model of type evolution. However, observing type changes in persistent systems has shown that types most commonly exhibit additive evolution. Even though inclusion captures this pattern in the case of record types, it does not always do so for other type constructors. The confusion of subtyping, inheritance and evolution often leads to unsound or at best, dynamically typed systems. Existing solutions to this problem do not completely address the requirements of type evolution in persistent systems. The aim of this thesis is to develop a form of polymorphism that is suitable for modelling additive evolution in persistent systems. The proposed strategy is to study patterns of evolution for the most generally used type constructors in persistent languages and to define a new relation, called extension, which models these patterns. This relation is defined independent of any existing relations used for dealing with evolution. A programming language mechanism is then devised to provide polymorphism over this relation. The polymorphism thus defined is called extension polymorphism. This thesis presents work involving the design and definition of extension polymorphism and an implementation of a type checker for this polymorphism. A proof of soundness for a type system which supports extension polymorphism is also presented.
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McLure, Craig Anthony. "Duplication and polymorphism with particular reference to regulators of complement activation." University of Western Australia. Centre for Molecular Immunology and Instrumentation, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0103.
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[Truncated abstract] For the convenience of the reader, detailed figures and tables have been enlarged and compiled in Appendix 2, at the end of this thesis. This thesis is presented as an approach to identify, annotate and detect genomic duplication and polymorphism within large genomic regions. To demonstrate this, I have used as a model, the genomic region known as the Regulators of Complement Activation (RCA). The RCA complex is located on the long arm of chromosome 1 at position 1q32 and is a reservoir of complement regulatory proteins. The genes of the RCA share many similarities implying that all have arisen through multiple complex duplication events. My analysis of this region in the following chapters demonstrates the complexity of this duplication and identifies the many functional units within the RCA. It was my aim at the beginning of these studies to demonstrate an approach that could define the Ancestral Haplotypes (AHs) of the RCA gene cluster. To do this, extensive genomic analysis was required and the ever-increasing availability of genomic sequence has made this thesis possible. Each of the chapters serves to address the following aims set out at the beginning of this thesis: 1. Further characterise the relationship between the genes (Complement Control proteins-CCPs) and domains of the Regulators of Complement Activation (RCA). 2. Identify and examine the duplicated elements within the RCA. - 6 - 3. Examine the effects of retroviruses and other insertions and deletions (indels) in generating the divergence of duplicated genes. 4. Investigate the applicability of the Genomic Matching Technique (GMT) to define AH within the region. 5. Examine association of AHs with CCP implicated diseases. 6. Determine the GMT applicability in non-human species
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Li, Wenjing. "Nucléation non-photochimique induite par laser (NPLIN) : Contribution au mécanisme de nucléation à travers des études expérimentales sur le sulfathiazole, L-acide glutamique et la glycine et la modélisation de quelques petites molécules." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLC019.
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Cette thèse a pour but de démontrer la faisabilité de la technique de Nucléation non-Photochimique Induite par Laser (NPLIN) appliquée aux composés pharmaceutiques organiques. Avec nos résultats expérimentaux, ceux obtenus dans la littérature et calculs théoriques ab initio, nous avons discuté du mécanisme de la méthode NPLIN.Cette thèse a décrit en premier lieu, le nouveau montage expérimental semi-automatisé adapté aux exigences des études NPLIN développé à CentraleSupelec. Des expériences NPLIN sur le sulfathiazole (STZ), l-acid glutamique (LGA) et la glycine (GLY) sont menées pour étudier l’impact des paramètres du laser et de la sursaturation des solutions sur leur cristallisation. Les résultats expérimentaux montrent que la technique NPLIN permet d’obtenir des cristaux de STZ, LGA and GLY. L’efficacité de la nucléation croit avec l’augmentation de la densité d’énergie du laser et de la sursaturation. Un indice nouveau Ind50 a été défini correspondant au couple densité d’énergie/sursaturation où 50% nucléation est atteinte. Son comportement est discuté. Il est trouvé que le nombre cristaux STZ induits par laser dépend linéairement avec le temps d’irradiation. Une dépendance du polymorphe des cristaux induit par le laser avec la polarisation du faisceau laser est également découvert pour STZ et GLY. Un autre indice Det(A) est utilisé pour caractériser l’impact de la polarisation sur le polymorphisme. Des calculs théoriques ab initio par le logiciel Gaussian09 permettent de donner une estimation des énergies d’interaction des différents dimères pour des polymorphes de STZ, LGA, GLY, l-histidine (LH) et urée. L’empilement des molécules dans les clusters pré-existant est prédit en accord avec la détermination des énergies d’interaction. L’analyse de corrélation entre la symétrie d’empilement et des résultats expérimentaux souligne l’hypothèse de l’effet Kerr pour expliquer cet impact de la polarisation du faisceau laser sur le polymorphismeThis thesis concerns the demonstration of the feasibility of Non-Photochemical Laser Induced Nucleation (NPLIN) of some organic pharmaceutical compounds. Using our experimental results and those obtained in literature together with ab initio theoretical calculations we have been able to discuss the mechanism of the NPLIN method.This thesis presents a new experimental set-up developed at CentraleSupelec and dedicated to perform NPLIN experiments. NPLIN experiments on sulfathiazole (STZ), l-glutamic acid (LGA) and glycine (GLY) have been carried out to examine the impact of laser parameters and solution supersaturation on their crystallization. Experimental results show that crystals of STZ, LGA and GLY have been obtained by means of NPLIN. For these compounds, nucleation efficiency increases with laser power density and solution supersaturation. A new index Ind50 corresponding to the couple (energy density/supersaturation) where 50% of nucleation is teached, has been defined. Its behavior has been discussed. It was found that laser induced STZ crystal number depends almost linearly on exposure duration. Moreover, for STZ and GLY, a dependance of laser induced crystal polymorph on laser polarization has been found. Another new index Det(A), has been used for characterization of the impact of the polymorphism. Ab initio quantum computations using Gaussian09, provided an interaction energy estimate for different dimers in different polymorphs of STZ, LGA, GLY, l-histidine (LH) and urea. Packing mode in pre-existing clusters is predicted in agreement with interaction energy determinations. Correlation analysis between packing symmetry and experimental results, shed new light on the Kerr effect hypothesis relative to the impact of laser polarization on polymorphism
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Lamarche, François 1955. "Modelling polymorphism with categories." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75961.
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In this work we describe a category of domains, whose objects are in general categories instead of posets, such that J.-Y. Girard's category of qualitative domains and stable functions is contained in it as a full subcategory. We describe two ways of interpreting Martin-Lof type theory in this category, the first one allowing $ Sigma$ and $ Pi$, the second one only $ Pi$. Finally we show how to extend the second interpretation to a model of the theory of constructions.
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Bano, Anthony M. "Polymorphism in biomineral nanoparticles." Thesis, University of Warwick, 2012. http://wrap.warwick.ac.uk/49891/.
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Biomineralisation is the process by which living things produce hard mineral tissues with unique physical properties. The study of this process can help us produce biomimetic materials, reproducing such properties, with the study of nucleation and crystallisation of the materials being particularly important. I have used molecular simulation techniques to help gain a greater understanding of these processes, focussing particularly on identifying the conformations and solid phases available to nanoparticles of two biomineral compounds. The bones and teeth of mammals are made largely of calcium phosphates. I have used metadynamics to study nanoparticles of tricalcium phosphate (TCP) and have identified high and lower order configurations. To facilitate this work I reviewed the extant empirical potentials for calcium phosphate systems, selecting the most appropriate for TCP. Calcium carbonate, found in examples throughout the animal kingdom, has three crystalline polymorphs relevant to biomineralisation: calcite, aragonite and vaterite. While nanoparticles of calcite have been extensively studied the other polymorphs have been neglected to date. In this work I present a technique for predicting crystalline morphologies for all three polymorphs across a range of sizes, and compare the energetic ordering. In water the energetic ordering of the nanoparticles is heavily dependent on nanoparticle size. Furthermore, I present work calculating the surface enthalpies of a variety of calcium carbonate surfaces, many of which are negative. It appears that entropic penalty of ordered water is key to understanding the stability of nanocrystals. Also presented is an application of the nudged elastic band method to study transitions between nanoparticle crystal conformations. Between all three crystal polymorphs the nanoparticles passed through an amorphous region of phase space. These results have also been used to evaluate order parameters for use in metadynamics simulations.
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Wilkie, Susan Elizabeth. "DNA polymorphism in Allium." Thesis, University of Hertfordshire, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332242.
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Pidvysotska, N. I. "Polymorphism of Edwards syndrome." Thesis, БДМУ, 2017. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/17149.
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Maneggia, Paola. "Models of linear polymorphism." Thesis, University of Birmingham, 2004. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414964.
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Saraph, A. "Nucleotide polymorphism in schizophrenia." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2002. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2774.
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Zhang, Shuohao. "Supporting polymorphism in XML data." Online access for everyone, 2006. http://www.dissertations.wsu.edu./Dissertations/Summer2006/s%5Fzhang%5F071906.pdf.
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Ogbebor, Omokhaye P. "Studies on rabies virus polymorphism." Thesis, University of Ottawa (Canada), 2002. http://hdl.handle.net/10393/6079.
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Rabies viruses have very simple genomes made up of single-stranded, negative sense, non-segmented ribonucleic acid (RNA). Most, if not all RNA virus populations may exist as complex mixtures of genetic and phenotypic variants often referred to as quasispecies populations. A quantitative relative fitness assay has previously been used to demonstrate loss of fitness in RNA virus populations due to Muller's Ratchet and to show gains of fitness by natural selection during virus passages. Due to their mutation rates, rapid replication, large population sizes and controlled (variable or constant) host cells, RNA viruses are useful for examining evolutionary processes. This study uses rabies virus as a model to examine virus evolution and virus population biology. The fate of two closely related rabies virus variants (the Western Skunk and Eastern Artic Fox viruses), cloned using end-point dilution techniques, passaged by themselves and in competition to each other in mouse neuroblastoma (MNA) cells was investigated. (Abstract shortened by UMI.)
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Hafez, Ismail Mahmoud. "Lipid polymorphism and intracellular delivery." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0021/NQ56555.pdf.
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Wang, Wei. "Plasminogen polymorphism in dairy cattle." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26174.
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A genetic approach to lowering protease (plasmin) levels in milk, requires the presence of polymorphism of bovine plasminogen. This study was conducted to determine to what extent genetic polymorphism exists in dairy cattle. Bovine plasminogen was first purified from Holstein cow plasma by affinity chromatography on Lysine-Sepharose and antibodies to bovine plasminogen were raised by monthly intramuscular injection of the isolated bovine plasminogen into rabbits. For plasminogen phenotyping, blood samples were collected at random from 50 Holstein and Ayrshire cattle, and plasminogen was isolated from the plasma using lysine-Sepharose and then treated with neuraminidase. After separation by isoelectric focusing (pH 3.5-9.5) in polyacrylamide gels, Plasminogen polymorphs were detected immunologically using rabbit anti-bovine plasminogen antibodies. Additionally, the plasminogen isoforms were evaluated with a functional assay (caseinolytic overlay technique) after activation of the plasminogen with urokinase. Six plasminogen phenotypes were identified which represent products of 5 variant alleles. The 5 plasminogen variants were characterized based on their isoelectric points and designated PLG A$ sb2$ (pI 6.5 and 7.0), B$ sb2$ (pI 7.6 and 7.8), C$ sb1$ (pI 6.8), D$ sb2$ (pI 7.8 and 8.0), and E$ sb2$ (pI 6.8 and 7.0). PLG A$ sb2$ and PLG B$ sb2$ were the most common variants in these cattle. The 6 phenotypes were $ rm A sb2A sb2, B sb2B sb2, A sb2B sb2, B sb2C sb1, A sb2D sb2 and D sb2E sb2$. The phenotypic frequencies in Holstein and Ayrshire were very different, $ rm A sb2A sb2 and B sb2B sb2$ being respectively the most frequent phenotype. In addition, DNA polymorphism at bovine plasminogen gene was detected when genomic DNA was digested with the restriction enzyme Msp I and hybridized with mouse plasminogen cDNA. This is the first description of plasminogen polymorphism reported in dairy cattle. If different variants have altered activity, the detrimental effect
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Budd, Laura Elizabeth. "Polymorphism in small organic compounds." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/3967.
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The effect of temperature on the crystal structure of deuterated piperidine has been studied using neutron powder diffraction. Differential scanning calorimetry indicates that there are multiple phases accessible via changes in temperature however there is no evidence of this in the neutron powder diffraction study with only one phase observed in the range 2 – 250 K and under various crystallisation conditions. The effect of pressure up to 2.79 GPa has also been determined. The compression of the structure is facilitated through the closing up of voids in the structure and no phase transition is observed. Differential scanning calorimetry has shown N-methyl and N,N-dimethylformamide both exhibit a thermal event prior to melting. Low temperature neutron powder diffraction has shown these transitions are associated with the onset of methyl group rotation. Neutron powder diffraction studies show formamide exhibits remarkable polymorphism at ambient temperature and pressures between 0.1 GPa and 3.6 GPa, forming four new polymorphs. All the structures consist of N-H…O hydrogen bonded chains. The formation of the various polymorphs can be rationalised in terms of the orientation of the molecules within the hydrogen bonded chains and the resultant structures formed by further hydrogen bonds between the chains. This is in stark contrast to the effect of varying conditions of temperature where only one structure exists from 2 K right up to the melting point. The effect of temperature on the crystal structure of pyrazine in the range 8 – 315 K is described. At temperatures below 90 K the structure undergoes a phase transition to a previously uncharacterised phase, designated phase IV, which is closely related to the previously known phase I. The crystal structure of phase III has been determined at 315 K. The crystal structure of pyrazine has been determined at room temperature at pressures between 0.11 GPa and 9.36 GPa. At 0.94 GPa a transition from phase I to phase IV is observed. This is the same phase as observed at low temperatures. Crystal growth at 215 K results in the formation of two different phases of mesitylene; phase II and a new previously unknown phase designated phase IV. The structure of phase IV has been determined and found to be stable in the range 90 – 221 K. On cooling a crystal of deuterated mesitylene in phase II to 90 K a transition to phase III was observed and the resultant crystal structure is closely related to that of phase II.
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Fonseca, Gutierrez Maria del Carmen. "Genetic polymorphism in systemic sclerosis." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409294.
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Marshall, Karen Elizabeth. "Structural polymorphism of amyloidogenic peptides." Thesis, University of Sussex, 2010. http://sro.sussex.ac.uk/id/eprint/2447/.
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The folding of a protein from a linear chain of amino acids into its functional native state is one of the most widely investigated yet enigmatic events to take place in the natural world. An ever‐increasing number of proteins and peptides are known to fold, or “misfold”, into protease‐resistant amyloid fibrils that share a common cross‐β structure, despite having no apparent sequence homology. Self‐assembly of particular proteins or peptides into amyloid is believed to be the molecular basis of many diseases, including Alzheimer's Disease, Type II diabetes and the transmissible spongiform encephalopathies. More recent evidence suggests a functional, non‐pathogenic role for amyloid in certain organisms, which has inspired its use as a biomaterial. In order to understand these diseases and exploit amyloid for industrial use using a bottom‐up design approach, detailed knowledge of the assembly process and structure of amyloid is required. Many short peptides are known to assemble into amyloid‐like fibres in vitro that have very similar properties to those formed in vivo. These “model systems” can give deeper insight into what triggers, drives and influences self‐assembly. Furthermore, they can provide more detailed structural information than is often obtained from larger amyloid‐forming proteins. Using two short peptides (the yeast prion fragment GNNQQNY and the designed peptide KFFEAAAKKFFE), which form amyloid-like microcrystals that have been structurally characterised previously, the roles of particular residues in assembly and structure were investigated. Results reveal that aromatic residues are fundamental determinants of assembly and may contribute to polymorphic propensity. Furthermore, non‐aromatic sequence changes can have dramatic effects on fibril morphology both at a macromolecular level and in the underlying peptide packing arrangement. Structural variations were found between amyloid‐like fibres and microcrystals formed from the same peptide, which has implications for how to examine amyloid structure in the future. The balance of conditions required for proteins or peptides to adopt specific conformations is very fine. Polymorphism may be an inherent property of amyloidogenic proteins and peptides and detailing the structural intricacies of each form will be essential from both a biomedical and industrial perspective.
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Mitchell, John Edward. "Structural polymorphism in repeated DNA." Thesis, University of Portsmouth, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306945.
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Lundy, Zoe. "Functional consequences of MICA polymorphism." Thesis, University of Oxford, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.711616.
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Nguyen, Thi Yen. "Polymorphism of Organic Molecular Crystals." Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/18812.
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Die Kristallisation ist ein wichtiger Teilprozess bei der industriellen Herstellung vieler Materialien und Medikamente. Es ist jedoch ein vielschichtiger, physikalischer Vorgang, der noch nicht vollständig aufgeklärt ist.
Der Schwerpunkt dieser Arbeit liegt auf der Kristallisation von organischen, polymorphen Verbindungen aus unterschiedlichen Lösungsmitteln. Die Kristallisationsstudien wurden in einem akustischen Levitator mit Klimakammer, der den Einfluss von Temperatur, Feuchtigkeit und festen Oberflächen steuert, durchgeführt. Verschiedene analytische in-situ-Methoden und deren Kopplung kamen für die Analyse der Kristallisationsabläufe zum Einsatz. Als Unterstützung für die Interpretation der beobachteten Phänomene wurden unter äquivalenten Bedingungen Moleküldynamik-Simulationen vorgenommen.
Die Kristallisation der Modellverbindungen zeigte verschiedene spezifische Kristallisationspfade, die nicht dem klassischen Kristallisationsmodell entsprachen. Zunächst verdampfte das Lösungsmittel, was mit einer Konzentrationszunahme der Lösung und der Ausbildung von charakteristischen amorphen Phasen (Polyamorphismus) einherging, und schließlich trat die Kristallisation ein. Durch die oberflächenfreie Kristallisation wurde ausschließlich nur ein Polymorph ein- und derselben Verbindung als Kristallisationsprodukt isoliert. Die gezielte Wahl der Ausgangskonzentration und eines Lösungsmittels ermöglichte die Steuerung des Kristallisationsverlaufs hin zu einer gewünschten Kristallstruktur des untersuchten Materials.
Die Ergebnisse dieser Arbeit unterstützen das Verständnis über den komplexen Ablauf des Kristallisationsvorgangs, gleichzeitig zeigen sie weitere Ansätze auf, die Kristallisation zu untersuchen. Die neuen Erkenntnisse sind hilfreich bei der Optimierung der Herstellungsprozesse verschiedener Materialien.Crystallization is a complex process, which is used in different processes in the industrial production of various materials. The limited understanding about its fundamental mechanisms challenges the control of crystallization and influences the quality of the materials. The research of this work concentrates on the crystallization studies of organic model systems (active pharmaceutical ingredients) from different organic solvents in an acoustic levitator. This specific sample environment regulates the influence that solid surfaces, temperature, and humidity have on the crystallization process. The investigations were performed with in situ analytical techniques and theoretical simulations to gain a comprehensive insight into processes, occurring intermediates, and required reaction conditions. The results show that the model systems follow specific crystallization pathways different than those predicted by the classical nucleation theory. The crystallization proceeded via the evaporation of the solvent and the formation of characteristic amorphous phases (polyamorphism) into one crystalline structure of the compound. The targeted choice of the solvent and the concentration enabled the guidance of the pathways, therefore, resulting in the isolation of one desired crystalline structure. The findings are of great interest and they help explain the crystallization mechanisms on a molecular level, which is a fundamental contribution for the optimization of manufacturing processes.
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Lejeune, Julien. "Génétique et génomique des récepteurs de faible affinité pour le IgG - Implications pour le développement et l'analyse de la variabilité des effets des anticorps thérapeutiques." Thesis, Tours, 2010. http://www.theses.fr/2010TOUR3140/document.
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Les récepteurs Fc jouent un rôle important en permettant aux cellules de l’immunité d’interagir avec lesanticorps, notamment thérapeutiques. Dans cette thèse, nous montrons que des mécanismes de recombinaisonhomologue, de knock-in par insertion rétrovirale et de duplication segmentale ont permis l’acquisition chez lesPrimates (FCGR2A) puis chez les Hominidés (FCGR2C et FCGR3B) de gènes codant des récepteurs Fc ayantde nouvelles propriétés, tout en rendant instable ce cluster (variation de nombre de copies), et très complexeson analyse chez l’Homme. Grâce à une approche originale de pyroséquencage, nous sommes parvenus àétudier simultanément le polymorphisme allélique ORF/STOP du FCGR2C, ainsi que son nombre de copies.Nous avons ainsi révélé de nouveaux déséquilibres de liaison, s’ajoutant au déséquilibre FCGR3A-FCGR2Adont nous avons montré l’importance d’une prise en compte adaptée dans les études d’association avec laréponse aux anticorps thérapeutiques. Ces résultats devraient contribuer à améliorer le développement préclinique(pertinence des modèles animaux) et clinique (variabilité des effets) des anticorps thérapeutiquesFc receptors play an important allowing connexion between immune cells and antibody notably therapeutic. Inthis thesis, we have shown that homologous recombination events, knock-in by retroviral insertion andsegmental duplication led to the acquisition in primates (FCGR2A) then in Hominids (FCGR2C and FCGR3B)of genes coding for Fc receptors with new properties, led to genomic instability of the cluster (copy numbervariation) and to complex analysis in human. Through a original pyrosequencing approach, we have studiedsimultaneously ORF/STOP polymorphism and copy number variation of FCGR2C. We have also revealed newlinkage disequilibrium, additionnaly to FCGR3A-FCGR2A disequilibrium which we have shown theimportance of a suitable methdology in association studies with responses to therapeutic antibodies. Theseresults contribute to improve pre-clinical (of animal models) and clinical (variability effects) development oftherapeutic antibodies
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Genini, Sem. "Establishment of quick-methods to reveal DNA-polymorphisms single strand conformational polymorphism (SSCP) and heteroduplex analysis (HA) /." Zurich : Swiss Federal Institute of Technology, Department of Animal Sciences, Breeding Biology, 2002. http://e-collection.ethbib.ethz.ch/show?type=dipl&nr=50.
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Bilson, Richard C. "Implementing overload and polymorphism in Cforal." Waterloo, Ont. : University of Waterloo, [Dept. of Computer Science], 2003. http://etd.uwaterloo.ca/etd/rcbilson2003.pdf.
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Thesis (M.Math.)--University of Waterloo."A thesis presented to the University of Waterloo in fulfillment of the thesis requirement for the degree of Master of Mathematics in Computer Science". Includes bibliographical references.
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Svärd, Michael. "Crystal Polymorphism of Substituted Monocyclic Aromatics." Licentiate thesis, KTH, Chemical Engineering and Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10501.
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Bilson, Richard C. "Implementing Overloading and Polymorphism in Cforall." Thesis, University of Waterloo, 2003. http://hdl.handle.net/10012/1166.
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The programming language Cforall extends the C language with, among other things, overloading, parametric polymorphism, and functions that can return multiple values from a single call. This thesis presents an outline of the first implementation of the core Cforall language. An effective implementation of Cforall requires complete support for new language constructs while preserving the behaviour and efficiency of existing C programs. Analyzing the meaning of Cforall programs requires significantly more sophisticated techniques than are necessary for C programs; existing techniques for the analysis of overloading and polymorphism are adapted and extended to apply to Cforall. Three strategies for generating code for polymorphic programs are compared, using plain C as an intermediate representation. Finally, a realistic Cforall program is presented and characteristics of the generated C code are examined.
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Gracin, Sandra. "Solubility and polymorphism of molecular compounds /." Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-267.
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Keats, Clare J. "Crystallization and polymorphism of putative drugs." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404167.
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Atkinson, Kathryn. "The adaptive significance of plumage polymorphism." Thesis, University of Canterbury. Zoology, 2004. http://hdl.handle.net/10092/5813.
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Plumage polymorphism is displayed in a number of diverse species and therefore, is presumed to have evolved independently on multiple occasions. To date, no study has established whether any of the hypotheses proposed to explain its evolution in single species are relevant across all avian taxa. Using comparative analyses which included all species displaying a plumage polymorphism involving melanin pigmentation, I found no support for either sexual or apostatic selection being responsible for the evolution of plumage polymorphism. Weak support for a role for disruptive selection was indicated in certain species but not when all polymorphic species were considered together. Contrary to previous studies, this indicates that plumage polymorphism may not confer any selective advantage but may in fact be selectively neutral or perhaps simply a product of historical biogeographic processes. Many polymorphic species have clinal morph-ratio distributions. In the polymorphic New Zealand fantail, Rhipidura fuliginosa, I established that the black morph was more common in central parts of the South Island of New Zealand than in the South. This was not the pattern expected based on previous studies and no environmental factor was found to correlate with the distribution. Polymorphism may not confer a selective advantage to a species as a whole, but the fact that two or more often very differently coloured morphs can persist within a population suggests that balancing selection may be in operation. I demonstrated that black morph fantails suffered reduced feather damage over the course of the year and that black and pied fantails differed slightly in foraging behaviour. The benefits of black and white plumage whilst foraging were further elucidated through plumage manipulation experiments. Thus, a trade-off between feather wear and foraging between the two morphs of the fantail, produced due to the different selective advantages provided by their plumage colouration, seems likely to be part of the balancing selection mechanism responsible for maintaining the plumage polymorphism in this species. Plumage polymorphism may be better understood if the mechanisms controlling plumage evolution in general were unravelled. Therefore, I reconstructed plumage characters of the genus Rhipidura onto a molecular phylogeny that I created based on the cytochrome b gene. Species that were divergent in plumage were also found to be more genetically divergent. This suggested that, unlike in other genera, the plumage characters of the Rhipidura spp. may be a good estimator of phylogenentic relationships.
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Koesters, Nils B. "Investigating life-history polymorphism : modelling mites." Thesis, University of Stirling, 2005. http://hdl.handle.net/1893/21630.
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The thesis presents research on the life-history polymorphism in the mite Sancassania berlesei. Males of this species are andropolymorphic: there are two distinct male phenotypes. One, the fighter, develops a third thickened leg pair, with which it kills off other fighters and males which do not exhibit a third thickened leg pair, the non-fighters. A review of the life-history of S. berlesei is given, focussing on its general biology, diet, dispersal and mating behaviour. This is followed by a review of the andropolymorphism, and the current understanding of the mechanisms underlying it. The major conclusions from the experimental work presented in this thesis are that fighters primarily develop at low population densities; though the proportion of males becoming fighters at any given density may change over time. This change is likely to be due to condition-dependence. Data is presented to illuminate these matters and a model is developed linking fighter development to the costs of being a fighter (in terms of survival) and the benefits of being a fighter (in terms of fecundity). The sex ratio in S. berlesei is 1:1, and there is no evidence of density or frequency-dependent deviations from this. A delay in food supply at maturation delays the time of maximum fecundity of females for about seven days and lowers their overall egg output. Density-dependent effects reduce the overall daily fecundity of females in higher densities. Female survival is affected by density, food present and rearing conditions. Nearly all eggs laid by S. berlesei hatch regardless of the conditions. Eggs laid in very poor conditions hatched even earlier than the average time of between day three and four. At density two, animals do synchronise their frequency, when isolated together from egg stage. Poor conditions reverse female density-dependence from convex to concave with the lowest life expectancy at intermediate densities. The trade-off between survival and fecundity is the likely cause. Amalgamating the results from the previous experiments, the influence of stochastic population dynamics on male strategy was then modelled. The results indicate that the fighter morph development rule is sensitive to the probability of low population densities arising. When low densities occur, there is a selective advantage to being a fighter. With increasing probability of lower densities, becoming a fighter is more feasible. The ESS rule changes, while in a stable high density environment a density-dependent fighter rule is never selected for. This indicates an influence of stochastic population dynamics on life-history evolution. Modelling demographic stochasticity in the fighter rule shows some buffering effect of this form of stochasticity. The fighter morph determination rule is less sensitive to environmental stochasticity with a high frequency of low densities. Using an agent based model with diploid genetics, I show that under high densities a fighter male is less successful at passing on his genes than a non-fighter. At a density of one male, the fighter gains no advantage to developing the fighter phenotype (as he is not competing with other males). In this case, the advantage may arise through future increases in density (such as through immigration or maturation of offspring). The density-dependent fighter development rule is then switched within the model from density-dependent to frequency-dependent, and the model indicates, that even under the frequency-dependent rule a possible ratio of fighters to non-fighters could exist. The system does not reach this state due to condition-dependence in reality. Following on from the findings discussed above, that morph determination has a condition-dependent component, I develop an argument that relates the observed forms of morph determination (density-dependent and frequency-dependent) in three closely related species of mites via an underlying condition-dependence. It is shown that condition-dependence is likely the linking factor between frequency and density-dependence. This is shown to be possibly a rule for all species displaying polymorphism which includes physical alterations of their bodies.
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Lancaster, R. W. "Studies of polymorphism by physical methods." Thesis, University of East Anglia, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378885.
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Bartle, Elizabeth Anne. "The polymorphism of binary lipid mixtures." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305427.
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Hogan, J. L. "The polymorphism of headgroup methylated phosphatidylethanolamines." Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235235.
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Lai, Tsai-Ta Christopher. "Control of polymorphism in continuous crystallization." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104203.
Full textAbstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references.
Continuous manufacturing has gained significant interest in recent years as the ultra-lean mode of pharmaceutical production. Albeit the increasing number of studies on the process dynamics in continuous crystallization, in particular in yield improvement and impurity separation, the research community lacks the systematic understanding of the control of polymorphism in continuous crystallization. Variations in the polymorphism of the active pharmaceutical ingredient can undermine the bioavailability and the downstream processability of the drug substance. Thus, precise control of the drug polymorphism is pivotal for delivering quality drug products to the patients. In this thesis work, we aimed to develop a series of steps forward in understanding the polymorph dynamics in continuous crystallization, notably in mixed-suspension, mixed-product removal (MSMPR) crystallization. We first elucidated the major intrinsic and extrinsic factors which govern the process polymorphism in both monotropic and enantiotropic polymorphic compounds. Using the monotropic L-glutamic acid as the model compound, two temperature regimes each with distinctive kinetic and thermodynamic characteristics were identified. It is found that at high temperatures, the polymorph dynamics is mediated by the relative thermodynamics of the polymorphs. The most stable form is likely to be the dominant form at steady state. On the other hand, at low temperatures, the interplay of the crystal growth and nucleation kinetics is found to play an important role in determining the final polymorphism. Similar results were identified in the enantiotropic p-aminobenzoic acid system where three temperature regimes were identified. The additional regime is located near to the transition temperature where the chemical potential of the two polymorphs are identical. The steady state polymorphism is thereby determined by the kinetic energy barriers for the crystallization of the polymorphs. The study of polymorphism was also conducted in cooling-antisolvent crystallization and the effect of solvent composition on the polymorph dynamics was studied. In addition, the dynamic pathways connecting the startup states to the metastable steady states and the stable steady states were determined. The polymorphic transition between these steady states was observed and analyzed. The fundamental understanding of the kinetic competition and the governing dynamics in polymorphic crystallization forms the backbone for developing the polymorph control strategies in this thesis. Based on the polymorph dynamic studies, we designed MSMPR cascade systems to control the process polymorphism. In addition, systematic procedures are established to facilitate the design and optimization of continuous crystallization with the objectives to control polymorphism, optimize process yield and achieve the target crystal size distribution. The operational window is determined within which these control objectives are achieved. As there are increasing interests in transitioning pharmaceutical manufacturing from batch to continuous processing, the results in this thesis should develop a substantial position in the body of scientific literature.
by Tsai-Ta Christopher Lai.
Ph. D.
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Boyer, Stephan. "The kernel of ad hoc polymorphism." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/106072.
Full textAbstract:
Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (page 41).
Ad hoc polymorphism allows a value to take on multiple types, with a separate definition of the value provided for each type. We offer a new formalization of this old concept as a typed lambda calculus. Motivated by the aspiration of extending System F with ad hoc constraints, we introduce a new mechanism for implicit parameter passing. Putting these ideas together, we present a practical replacement for bounded type quantification with simpler metatheory.
by Stephan Boyer.
M. Eng.
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剛貴, 田中, and Goki Tanaka. "Structural polymorphism of alpha-synuclein fibrils." Thesis, https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB13115616/?lang=0, 2019. https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB13115616/?lang=0.
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Satarifard, Vahid. "Polymorphism of Biomembranes at the Nanoscale." Doctoral thesis, Humboldt-Universität zu Berlin, 2021. http://dx.doi.org/10.18452/22252.
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In dieser Arbeit untersuchen wir den Polymorphismus von Biomembranen im Nanometerbereich anhand von Computermodellen. In Kapitel drei werden auf Dissipative Particle Dynamis basierende molekulare Simulationen genutzt, um die Wechselwirkungen zwischen Membranen und Nanotropfen mit hohen Oberflächenspannungen in der Größenordnung von Milli Newton pro Meter zu untersuchen. Wir zeigen, dass Nanotropfen eine negative Linienspannung an der dreiphasigen Kontaktlinie mit der Membran aufweisen. Die negative Linienspannung führt zu einem spontanen Symmetriebruch des Membran-Tropfensystems und zur Bildung eines enggeschlossenen länglichen Membranhalses. In Kapitel vier untersuchen wir Nanotropfen mit niedrigen Grenzflächenspannungen in der Größenordnung von Mikro-Newton pro Meter. Eine Energieminimierung ermöglicht uns, eine Vielzahl von Parametern zu variieren und die Abhängigkeit der Membranbenet-zungsphänomene von der Grenzflächenspannung, der Biegesteifigkeit, der Linienspannung und der spontanen Krümmung systematisch zu bestimmen. Wir beobachten eine neue morphologische Transformation, die sowohl die Vesikel als auch das Tröpfchen betrifft und eine weiter Geometrie mit gebrochener Rotationssymmetrie. Schließlich bestimmen wir die Grenze zwischen symmetrischen und asymmetrischen Kontaktlinien innerhalb des dreidimensionalen Parameterraums bei verschwindender spontanen Krümmung. In Kapitel fünf verwenden wir molekulare Simulationen, um die morphologischen Transformationen einzelner Nanovesikel mit unterschiedlichem Grad an Asymmetrie zwischen den beiden Schichten der Doppelmembranen zu beobachten. Wir beginnen mit kugelförmigen Vesikeln, die ein bestimmtes Wasservolumen einschließen und aus einer bestimmten Gesamtzahl von Lipiden bestehen. Wenn ihr Volumen verringert wird, verwandeln sich die kugelförmigen Vesikel in eine Vielzahl von nicht kugelförmigen Formen. Dieser Polymorphismus kann durch Umverteilung weniger Lipide zwischen der inneren und äußeren Schicht der Membranen kontrolliert werden.In this thesis, we use computational methods to study polymorphism of biomembranes at the nanoscales. In chapter three, we use molecular simulations based on dissipative particle dynamics to investigate the interaction of membranes with nanodroplets at high interfacial tensions of the order of milli Newton per meter. We find that nanodroplets have negative line tension at the three phase contact line on the membrane. The negative line tension leads to spontaneous symmetry breaking of the membrane-droplet system and formation of a tight-lipped membrane neck. In chapter four, we study nanodroplets with low interfacial tensions of the order of micro Newton per meter. We use energy minimization, which allows us to explore a wide range of parameters and to systemati-cally determine the dependence of membrane wetting phenomena on interfacial tension, bending rigidity, line tension, and spontaneous curvature. We observe a new morphological transformation that involves both vesicles and droplets, leads to another regime with broken rotational symmetry. Finally, we determine the boundary between symmetric and asymmetric contact line geometries within the three-dimensional parameter space in vanishing spontaneous curvature. In chapter five, we use molecular simulations to monitor the morphological transformations of individual nanovesicles with different degrees of asymmetry between the two leaflets of the bilayer membranes. We start with the assembly of spherical vesicles that enclose a certain volume of water and contain a certain total number of lipids. When we reduce their volume, the spherical vesicles transform into a multitude of nonspherical shapes such as oblates and stomatocytes as well as prolates and dumbbells. This polymorphism can be controlled by redistributing a small fraction of lipids between the inner and outer leaflets of the bilayer membranes. As a consequence, the inner and the outer leaflets experience different mechanical tensions.
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Mackay, Elaine A. "Polymorphism of cadmium-induced mussel metallothioneins." Thesis, University of Aberdeen, 1990. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU024434.
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Metallothioneins are ubiquitous sulphur-rich heavy metal binding proteins whose biosynthesis is induced in response to a variety of agents, including heavy metals. A number of isoforms of metallothionein are known to be induced by heavy metals in the common mussel Mytilus edulis, and recently interest has centred on the nature of these proteins and their possible utility as pollution indicator agents. Cadmium-induced metallotheioneins were isolated from mussels by procedures which included gel permeation and anion-exchange chromatography. They were shown to comprise two molecular mass classes of 10 and 20KDa. The 10kDa class was resolved by anion-exchange into four components designated 10-I, 10-II, 1--III and 10-IV. The 20kDa class was similarly resolved into three components designated 20-I, 20-II and 20-III. The amino acid sequences of each of the components in both of the classes were determined. This involved digestion with a variety of proteinases and separation of the resulting peptides. The abundance of crysteines in these mussel metallotheioneins necessitated their derivatisation with methyl-p-nitrobenzenesulphonate to generate the S-methyl derivative of cysteine which has been found to be suitable for peptide mapping by HPLC and sequence analysis by automated methods. The components of the 20kDa class were shown to possess linked peptides consisting of 71 amino acids, which were distinct from the 72 amino acid peptides of the 10kDa class. It is suggested that the two monomers in the 20kDa proteins are linked via S-Cd-S bonding, i.e. a bridging cadmium ion. The various components within both classes exhibited homology, particularly with regard to the location of the cysteine residues, to metallothioneins from other species, including mammals. On the basis of this homology these proteins were classified as class I metallothioneins.
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Svärd, Michael. "Crystal polymorphism of substituted monocyclic aromatics /." Stockholm : Skolan för kemivetenskap, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10501.
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Hahn, Patrick Daniel. "Social control of polymorphism in Zootermopsis." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185916.
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The sex-specific effects of reproductives and of soldiers on the reproductivity (i.e., tendency to develop into replacement reproductives) of pseudergates of Zootermopsis nevadensis were studied. Reproductives inhibit reproductivity in pseudergates of their own sex only. Reproductives neither inhibit nor stimulate reproductivity in pseudergates of the opposite sex. Reproductives do not require the presence of a reproductive of the opposite sex to stimulate them to inhibit reproductivity in pseudergates. Soldiers had no effect on the reproductivity of pseudergates. The effects of group size and of the presence or absence of reproductives on the development of last-stage nymphs of Z. nevadensis were studied. The size of experimental groups had no effect on the rates of stationary molts or alate molts, suggesting that the correlation between colony size and the onset of alate production in nature may be spurious. The presence or absence of reproductives had no effect on the rate of stationary molts or alate molts, suggesting that in Z. nevadensis neither group size nor the presence of reproductives has any direct effect on alate determination. It is suggested that in Z. nevadensis a form of nutritional castration can delay the onset of alate development; that is to say, that the onset of alate development is determined by the ratio of nutrient-gathering castes to nutrient-receiving castes in the colony. I have found what I believe to be an extraordinary example of deception in Z. nevadensis and Zootermopsis angusticollis. This is the first reported example of caste mimicry in a social insect, and may explain why supernumerary replacement reproductives are common in Z. nevadensis and Z. angusticollis but not in Zootermopsis laticeps. The compositions of 41 field-collected colonies of Zootermopsis were given and the data were analyzed for trends. Most notably, supernumerary replacement reproductives were common in Z. nevadensis and in Z. angusticollis but have never been found in Z. laticeps, by us or by anybody else. These findings are in accordance with our hypothesis of "caste mimicry" in Z. nevadensis and Z. angusticollis.
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Mahmoudi, Abd-elrachid. "Etude génotypique et phénotypique des polymorphismes du récepteur du complément de type 1 (CR1,CD35) dans la maladie d’Alzheimer." Thesis, Reims, 2015. http://www.theses.fr/2015REIMM201/document.
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Les études d'association pangénomiques ont permis d'identifier de nouveaux loci, dont le gène CR1 comme associé au risque de maladie d'Alzheimer (MA). Le récepteur du complément de type 1 (CR1) est une glycoprotéine transmembranaire, présente notamment à la surface des érythrocytes (CR1E), mais également dans le plasma sous forme soluble (CR1s). Le CR1 peut prendre des formes fonctionnelles différentes, qui pourraient conférer des niveaux de risque différents, voire suggérer des mécanismes physiopathologiques de la MA. Si la relation entre CR1 et MA est aujourd'hui connue, son mécanisme reste énigmatique.L'objectif principal de cette thèse était de corréler aux données génétiques (single nucleotide polymorphisms, polymorphismes de longueur, polymorphismes de densité), des éléments phénotypiques acquis comme la densité du CR1E ou le CR1S. D'une part, notre étude a montré grâce à deux méthodes différentes, que la MA était associée à une densité basse de l'isoforme long de CR1 (CR1*2) et suggérait l'existence d'allèle silencieux de CR1. D'autre part, nous avons montré que même si les critères génétiques étaient respectés, certains phénotypes pourraient être acquis au cours de la maladie. Nos résultats suggèrent que la MA résulterait plus d'une insuffisance d'épuration des dépôts amyloïdes, que d'une réponse excessive dont la réaction inflammatoire serait délétère. Bien que cette recherche génotypique et phénotypique, à potentiel physiopathologique, nécessite des investigations à plus grande échelle, elle pourra ouvrir la voie à des nouvelles pistes thérapeutiques qui ne peuvent être envisagées aujourd'hui faute de vue claire du ou des mécanismes en causeGenome-wide association studies have identified new loci, including the CR1 gene, as being associated with Alzheimer's disease (AD) risk. The complement receptor type 1 (CR1) is a transmembrane glycoprotein found on the surface of erythrocytes (CR1E), and also in the plasma in soluble form (CR1s). CR1 can have different functional forms that may confer different risk levels, or even suggest pathophysiological mechanisms of AD. Indeed, the relation between CR1 and AD is now well established, the mechanism of this association remains to be elucidated.The main objective of this thesis was to correlate acquired phenotype elements, such as density of CR1E (number of CR1 antigenic sites per erythrocyte) or CR1s with genetic data (single nucleotide polymorphisms, length and density polymorphisms). Firstly, our study showed using two different methods that AD is associated with low density of the long CR1 isoform (CR1*2) and suggested the possible existence of silent CR1 alleles. Secondly, we showed that although genetic criteria were met, some phenotypes could be acquired during the course of the disease. Our findings suggest that AD stems more from insufficient clearance of amyloid deposits than from excessive response whose inflammatory reaction might be deleterious. Although this genetic and phenotypic study with pathophysiological potential still require further investigation on a larger scale, she could pave the way towards new therapeutic avenues that currently remain elusive in the absence of a clear overview of the mechanisms involved
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Afridi, Sarwat. "Influence de variants génétiques candidats sur des phenotypes liés au paludisme à Plasmodium falciparum et effet fonctionnel du polymorphisme NCR3-412 associés au paludisme." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4037.
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Le paludisme est une cause majeure de morbidité et de mortalité, plus particulièrement en Afrique sub-saharienne. De très nombreuses observations sont en faveur de l'existence de facteurs génétiques contrôlant le devenir de l'infection palustre. Il est très probable que certains variants génétiques de gènes candidats du paludisme affectent la résistance du paludisme à travers leur effet sur la réponse immunitaire acquise. Afin de vérifier cette hypothèse, nous avons étudié, dans une population vivant au Burkina Faso, des variants génétiques de HBB, IL4, IL12B, TNF, LTA, FCGR2A et NCR3 dont l'association avec des phénotypes liés à la résistance au paludisme a été publiée; nous avons évalué leur influence sur les niveaux d'IgG dirigés contre les antigènes de Plasmodium falciparum en utilisant un test d'association basé sur les familles. Ainsi, nous avons détecté, l'effet de l'hémoglobine C, FCGR2A-H131, le TNF-857T, et TNF1304A sur les niveaux des sous-classes d'IgG anti-P. falciparum. Ces résultats constituent une base utile pour des études ultérieures du contrôle génétique de la réponse immunitaire chez des individus vivant dans une zone d'endémie. Un autre projet a porté sur l'étude fonctionnelle du polymorphisme NCR3-412, dont nous avions montré l'association avec les accès palustres simples. Nos résultats basés sur des techniques moléculaires montrent l'effet de ce polymorphisme situé dans le promoteur sur la liaison de protéines nucléairesMalaria is the major cause of morbidity and mortality especially in the Sub-Saharan Africa. There is a growing body of evidence for genetic factors controlling the outcome of malaria infection. It is thought that some genetic variants of malaria candidate genes affect malaria resistance through their effect on the acquired immune response. In order to verify this hypothesis, we worked on genetic variants of HBB, IL4, IL12B, TNF, LTA, FCGR2A and NCR3, which have been associated with malaria resistance phenotypes, to determine their influence on levels of anti-P. falciparum IgG in urban population of Burkina Faso. Using family-based association analysis, we detected the effect of Hemoglobin C, FCGR2A-H131, TNF-857T, and TNF1304A on the levels of anti-P. falciparum IgG. This study can pave the way towards further comprehension of genetic control of an individual's immune response against malaria. Another project focused on functional study of polymorphism NCR3-412, which has already been associated to mild malaria. We investigated the functional effect of this polymorphism located in the promoter by using molecular techniques and showed the effect of this polymorphism on the binding of nuclear proteins
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Liu, Shuk Ming. "Single nucleotide polymorphism in human microsomal glutathione s-transferase gene and colorectal cancer /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202003%20LIU.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003.Includes bibliographical references (leaves 95-105). Also available in electronic version. Access restricted to campus users.
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Takeuchi, Izumi. "Theories of Parametric Polymorphism and Data Types." 京都大学 (Kyoto University), 2000. http://hdl.handle.net/2433/180905.
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Kabbage, Mehdi. "Amplified fragment length polymorphism in Mycosphaerella graminicola." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/255.
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Jobs, Magnus. "Technology development for genome and polymorphism analysis /." Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-413-5/.
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Jordan, Gabriele. "Polymorphism of normal colour vision in humans." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240178.
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Taylor, P. "Recursive domains, indexed category theory and polymorphism." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384532.
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Anwar, Ghazanfar Ali. "Genetic polymorphism in proinflammatory cytokines in bronchiectasis." Thesis, University of Newcastle Upon Tyne, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.576646.
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Bronchiectasis is a disease characterised by chronic bronchial sepsis and exerts considerable morbidity in those affected. In approximately 50% of cases the aetiology is unknown (idiopathic), raising the possibility of genetic predisposition. Cytokines such as IL-1, IL-6, IL-8 and TNFα are potent neutrophil recruiting molecules and are abundant in bronchiectatic secretions. Cytokine polymorph isms can lead to constitutively high production, and have been associated with a number of chronic inflammatory states. Hypothesis: Gene polymorph isms associated with high cytokine production predispose to idiopathic bronchiectasis (IB). Aims and objectives: To determine if high production alleles of cytokines IL-1β, IL6, IL8, TNF and IFNG are associated with idiopathic bronchiectasis (I B). Frequencies of these alleles were compared in patients with IB, bronchiectasis of known cause and normal controls. Allele frequencies in IB were also correlated with clinical markers of disease severity. Methods Following ethical approval, prospectively recruited patients underwent extensive clinical. phenotyping. IB was established as a diagnosis of exclusion. Allele frequencies for candidate genes were determined by PCR, with control allele frequencies available from local blood donors. Comparisons were made by Chi Square tests. Results: 189 patients (95f, 94m), mean (SO) age 66.11 (11.52) years were recruited including 82 (43%) idiopathies, No differences in the candidate allele frequencies were found between IB with 200+ controls and bronchiectasis of known cause group (n=1 06). Within idiopathic group, IL8+781T, IL6-174C, and IL1B-511T alleles were significantly associated with daily sputum production. In addition, IL8+781T and IL6-174C were associated with high exacerbation frequency and positive Pseudomonas aeruginosa culture. IL-1 B+3953T was significantly under- represented in those with daily sputum production and positive Pseudomonas status. Conclusions: Gene polymorphisms predisposing to high cytokine production were not found to be associated with lB. Several alleles were found to significantly associated with more severe disease. Independent confirmation is required in an adequately powered study.
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Atan, Deniz. "Cytokine gene polymorphism in non-infectious uveitis." Thesis, University of Bristol, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492470.
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Non-infectious uveitis is a blinding intraocular inflammatory disorder with an autoimmune pathogenesis. Like other autoimmune diseases, uveitis has multifactorial and polygenic aetiology. The results of this study have shown that polymorphisms of the ILIO and TNF genes influence the susceptibility and seventy of uveitis. These polymorphisms were either known to correlate with altered transcription levels, or linked with other polymorphisms positioned within regulatory conserved non-coding sequences. Thus the identification of specific genetic variants that confer susceptibility or resistance to uveitis has provided insights into the pathogenesis of uveitis, and might allow the prediction of patients who will have aggressive disease to allow tailoring of treatment to the individual.
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Smith, Judith Alexis. "Polymorphism, parasites and fitness in Soay sheep." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270757.
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Semple, Colin A. M. "Maintenance of inversion polymorphism in Drosophila melanogaster." Thesis, University of Edinburgh, 1994. http://hdl.handle.net/1842/11380.
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The work which is presented investigated the maintenance of inversion polymorphism in both real and simulated populations. Observations were made of a naturally occurring polymorphism for the common cosmopolitan inversion In(3R)P in populations of the fruit fly Drosophila melanogaster. Male mating success and larval to adult viability were estimated in both inbred and outbred populations of Californian flies. In addition, departures from random mating were sought. Computer simulation of the maintenance of inversion polymorphism was also undertaken. The modelling examined the development of associative overdominance due to deleterious recessive mutations. The relevance of experimental and simulated results is discussed with regard to the existing literature.