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The Global ETD Search service is a free service for researchers
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Networked Digital Library of Theses and Dissertations.
Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
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Showing 21 to 29 of 29 (0.024 seconds)| 21 |
Avaliação da expressão de genes da via de Weimberg sobre o catabolismo de xilose na linhagem produtora de PHAMCL Pseudomonas sp. LFM046. / Evaluation of gene expression of the Weinberg pathway on the xylose catabolism in the de PHAMCL-producing strain Pseudomonas sp. LFM046.Sarmiento, Juan Camilo Roncallo 27 January 2017 (has links)
Polihidroxialcanoatos (PHA) são polímeros biodegradáveis, biocompatíveis e podem ser produzidos a partir de matérias primas renováveis. Pseudomonas sp. é capaz de produzir PHA com composição monomérica variada e com teor controlável, o que confere grande variedade de aplicações. Flux Balance Analysis (FBA) foi utilizado no ambiente Matlab pelo uso do software COBRA. Para a análise foi necessário construir um core de Pseudomonas pela modificação dum core de E. coli, e assim fosse possível obter um modelo mais aproximado. Como resultado foi gerada uma rede metabólica viável contendo os genes da via de Weimberg de C. crescentus no core construído. Paralelamente, a Pseudomonas sp. LFM046 foi repicada sucessivas vezes em meio mineral (MM). Testes simples foram feitos para verificar o perfil das colônias isoladas, além de amplificar e sequenciar o gene 16S rDNA. O resultado do BLAST foi uma identidade de 99% com o gene da Pseudomonas sp. IPT 046, confirmando que a bactéria pertence a género Pseudomonas e tem a capacidade de consumir xilose. / Polyhydroxyalkanoates (PHA) are biodegradable, biocompatible polymers and can be produced from renewable raw materials. Pseudomonas sp. is capable of producing PHA with varied monomer composition and with controllable content, which confers a great variety of applications. Flux Balance Analysis (FBA) was used in the Matlab environment by the use of COBRA software. For the analysis, it was necessary to construct a Pseudomonas core by modifying an E. coli core, so that a more approximate model could be obtained. As a result a viable metabolic network was generated containing the C. crescentus Weimberg pathway genes in the constructed core. In parallel, Pseudomonas sp. LFM046 was repeated successively in mineral medium (MM). Simple tests were done to verify the profile of the isolated colonies, in addition to amplifying and sequencing the 16S rDNA gene. The BLAST result was 99% identity with the Pseudomonas sp gene. IPT 046, confirming that the bacterium belongs to the genus Pseudomonas and has the ability to consume xylose.
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The Genetics of Systemic Lupus Erythematosus : The Specificity of IRF5 to SLE.Linga Reddy, MV Prasad January 2007 (has links)
<p>The breakdown of self-tolerance is the main driving force behind susceptibility to SLE. When this occurs, T and B cells are activated in an uncontrolled manner and produce autoantibodies against self fragmented DNA, RNA and sometimes other parts of the cell such as cardiolipin, phosphatidylserine, etc.</p><p>The mechanism behind the breakdown of self-tolerance may be genetic factors that are triggered by environmental factors. SLE is not caused by a single gene, but by many genes, and is thus a polygenic disease. So far only a few genes have been found to be associated with SLE including PDCD1, FcγRs, and PTPN22. The main aim of my thesis is to find susceptibility genes responsible for SLE.</p><p>Recently, a gene called IRF5 was found to be associated with SLE. In paper one, we performed a thorough study and confirmed its association to SLE. In addition, we found a few other SNPs in the gene that were associated to the disease. Among them, SNP rs2004640 is very strongly associated and was found to affect the splicing of the gene. Another SNP, rs2280714, correlated with overexpression of the gene, although SNP rs10954213 was much more highly correlated with expression adding to this, in paper two we found a few other SNPs that were associated to SLE and played crucial roles in gene function. An indel in exon 6, though not associated by itself, regulated which isoforms were expressed. Individuals with 2 repeats expressed isoforms V1 and V4, while individuals with 4 repeats expressed isoforms V5 and V6. SNP rs2070197 was also very strongly associated, but did not have a functional role. In paper three, the same polymorphisms were studied in a Mexican population, which showed an even stronger association when compared to a European population.</p><p>It is known that autoimmune diseases share susceptibility genes, therefore we wanted to see if the IRF5 gene is associated with any other autoimmune diseases. In papers four and five, we tested its association to RA (using three sets of patients and controls from Sweden, Argentina and Spain) and psoriasis (using a set of patients and controls from Sweden). Association was not found in either of the diseases. Therefore, we believe that this association may be SLE-specific.</p>
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The Genetics of Systemic Lupus Erythematosus : The Specificity of IRF5 to SLE.Linga Reddy, MV Prasad January 2007 (has links)
The breakdown of self-tolerance is the main driving force behind susceptibility to SLE. When this occurs, T and B cells are activated in an uncontrolled manner and produce autoantibodies against self fragmented DNA, RNA and sometimes other parts of the cell such as cardiolipin, phosphatidylserine, etc. The mechanism behind the breakdown of self-tolerance may be genetic factors that are triggered by environmental factors. SLE is not caused by a single gene, but by many genes, and is thus a polygenic disease. So far only a few genes have been found to be associated with SLE including PDCD1, FcγRs, and PTPN22. The main aim of my thesis is to find susceptibility genes responsible for SLE. Recently, a gene called IRF5 was found to be associated with SLE. In paper one, we performed a thorough study and confirmed its association to SLE. In addition, we found a few other SNPs in the gene that were associated to the disease. Among them, SNP rs2004640 is very strongly associated and was found to affect the splicing of the gene. Another SNP, rs2280714, correlated with overexpression of the gene, although SNP rs10954213 was much more highly correlated with expression adding to this, in paper two we found a few other SNPs that were associated to SLE and played crucial roles in gene function. An indel in exon 6, though not associated by itself, regulated which isoforms were expressed. Individuals with 2 repeats expressed isoforms V1 and V4, while individuals with 4 repeats expressed isoforms V5 and V6. SNP rs2070197 was also very strongly associated, but did not have a functional role. In paper three, the same polymorphisms were studied in a Mexican population, which showed an even stronger association when compared to a European population. It is known that autoimmune diseases share susceptibility genes, therefore we wanted to see if the IRF5 gene is associated with any other autoimmune diseases. In papers four and five, we tested its association to RA (using three sets of patients and controls from Sweden, Argentina and Spain) and psoriasis (using a set of patients and controls from Sweden). Association was not found in either of the diseases. Therefore, we believe that this association may be SLE-specific.
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The string quartets of Mieczysław Weinberg : a critical studyElphick, Daniel January 2016 (has links)
As attention on the music of Mieczysław Weinberg (1919-1996) has increased in the years after his death, so has the need for an analytical study of his musical style and language. This thesis surveys Weinberg’s changing style through a genre that spans almost his entire output: the string quartet. His close friendship and artistic affinity with Shostakovich helps make his music accessible to a wider audience, though closer examination reveals Weinberg’s individuality and a quite distinct language from that of his mentor. In support of this contention, a wide range of analytical approaches is deployed in this dissertation, along with a pragmatic methodology for presenting a holistic overview of Weinberg’s quartets. Weinberg’s quartet cycle occupies an important place in twentieth-century music, with parallels to Shostakovich, Bartók, and other Soviet composers, including Myaskovsky, Shebalin, Levitin, and Boris Chaykovsky; correspondences and distinctiveness are explored in the second chapter. The third chapter surveys Weinberg’s musical narratives, with recourse to theories from Kofi Agawu, Boris Asafiev, and Jacques Derrida. Form is the focus of the fourth chapter, where ideas from Mark Aranovsky, and James Hepokoski and Warren Darcy are deployed to highlight Weinberg’s problematising of traditional forms in his music. Chapter five explores Weinberg’s multi-faceted approach to harmony, with concepts expanded from Lev Mazel, Yury Kholopov, and the neo-Riemannian school of analysis. The picture that emerges is of Weinberg’s individuality and distinctive voice, manifested in a controlled experimentalism and a tendency towards extended lyricism. His affinity with better-known composers may prove an approachable entry-point for wider audiences, but many of the most striking elements in his quartet cycle are of his own invention. His quartets stand as an important contextual dimension for understanding Shostakovich’s cycle, and also for appreciating the broader repertoire of Soviet chamber music. As his centenary approaches, engagement with Weinberg’s music continues to increase: this thesis provides contexts and analysis-based conclusions to complement this ongoing revival.
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Weinbergböden in SachsenSohr, Antje, Scherer, Volker 23 March 2022 (has links)
Die Broschüre beschreibt die Vielfalt der Böden im sächsischen Weinanbaugebiet. Zahlreiche Profilaufnahmen erlauben einen Blick in die normalerweise dunklen Regionen. Außerdem wird auf die Bedeutung des Bodens als Schutzgut hingewiesen.
Redaktionsschluss: 15.01.2022
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Predictions of Effective Models in Neutrino PhysicsBergström, Johannes January 2011 (has links)
Experiments on neutrino oscillations have confirmed that neutrinos have small, but non-zero masses, and that the interacting neutrino states do not have definite masses, but are mixtures of such states.The seesaw models make up a group of popular models describing the small neutrino masses and the corresponding mixing.In these models, new, heavy fields are introduced and the neutrino masses are suppressed by the ratio between the electroweak scale and the large masses of the new fields. Usually, the new fields introduced have masses far above the electroweak scale, outside the reach of any foreseeable experiments, making these versions of seesaw models essentially untestable. However, there are also so-called low-scale seesaw models, where the new particles have masses above the electroweak scale, but within the reach of future experiments, such as the LHC.In quantum field theories, quantum corrections generally introduce an energy-scale dependence on all their parameters, described by the renormalization group equations. In this thesis, the energy-scale dependence of the neutrino parameters in two low-scale seesaw models, the low-scale type I and inverse seesaw models, are considered. Also, the question of whether the neutrinos are Majorana particles, \ie , their own antiparticles, has not been decided experimentally. Future experiments on neutrinoless double beta decay could confirm the Majorana nature of neutrinos. However, there could also be additional contributions to the decay, which are not directly related to neutrino masses. We have investigated the possible future bounds on the strength of such additional contributions to neutrinoless double beta decay, depending on the outcome of ongoing and planned experiments related to neutrino masses. / QC 20110812
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Renormalization in Field TheoriesSöderberg, Alexander January 2015 (has links)
Several different approaches to renormalization are studied. The Callan-Symanzik equation is derived and we study its beta functions. An effective potential for the Coleman-Weinberg model is studied to find that the beta function is positive and that spontaneous symmetry breaking will occur if we expand around the classical field. Lastly we renormalize a non-abelian gaugetheory to find that the beta function in QCD is negative.
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Models in Neutrino Physics : Numerical and Statistical StudiesBergström, Johannes January 2013 (has links)
The standard model of particle physics can excellently describe the vast majorityof data of particle physics experiments. However, in its simplest form, it cannot account for the fact that the neutrinos are massive particles and lepton flavorsmixed, as required by the observation of neutrino oscillations. Hence, the standardmodel must be extended in order to account for these observations, opening up thepossibility to explore new and interesting physical phenomena. There are numerous models proposed to accommodate massive neutrinos. Thesimplest of these are able to describe the observations using only a small numberof effective parameters. Furthermore, neutrinos are the only known existing particleswhich have the potential of being their own antiparticles, a possibility that isactively being investigated through experiments on neutrinoless double beta decay.In this thesis, we analyse these simple models using Bayesian inference and constraintsfrom neutrino-related experiments, and we also investigate the potential offuture experiments on neutrinoless double beta decay to probe other kinds of newphysics. In addition, more elaborate theoretical models of neutrino masses have beenproposed, with the seesaw models being a particularly popular group of models inwhich new heavy particles generate neutrino masses. We study low-scale seesawmodels, in particular the resulting energy-scale dependence of the neutrino parameters,which incorporate new particles with masses within the reach of current andfuture experiments, such as the LHC. / Standardmodellen för partikelfysik beskriver den stora majoriteten data från partikelfysikexperimentutmärkt. Den kan emellertid inte i sin enklaste form beskrivadet faktum att neutriner är massiva partiklar och leptonsmakerna är blandande,vilket krävs enligt observationerna av neutrinooscillationer. Därför måste standardmodellenutökas för att ta hänsyn till detta, vilket öppnar upp möjligheten att utforska nya och intressanta fysikaliska fenomen. Det finns många föreslagna modeller för massiva neutriner. De enklaste av dessakan beskriva observationerna med endast ett fåtal effektiva parametrar. Dessutom är neutriner de enda kända befintliga partiklar som har potentialen att vara sinaegna antipartiklar, en möjlighet som aktivt undersöks genom experiment på neutrinolöst dubbelt betasönderfall. I denna avhandling analyserar vi dessa enkla modellermed Bayesisk inferens och begränsningar från neutrinorelaterade experiment och undersöker även potentialen för framtida experiment på neutrinolöst dubbelt betasönderfall att bergänsa andra typer av ny fysik. Även mer avancerade teoretiska modeller för neutrinomassor har föreslagits, med seesawmodeller som en särskilt populär grupp av modeller där nya tunga partiklargenererar neutrinomassor. Vi studerar seesawmodeller vid låga energier, i synnerhetneutrinoparametrarnas resulterande energiberoende, vilka inkluderar nya partiklarmed massor inom räckh°all för nuvarande och framtida experiment såsom LHC. / <p>QC 20130830</p>
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Twentieth-century poetry and science : science in the poetry of Hugh MacDiarmid, Judith Wright, Edwin Morgan, and Miroslav HolubGibson, Donald January 2015 (has links)
The aim of this thesis is to arrive at a characterisation of twentieth century poetry and science by means of a detailed study of the work of four poets who engaged extensively with science and whose writing lives spanned the greater part of the period. The study of science in the work of the four chosen poets, Hugh MacDiarmid (1892 – 1978), Judith Wright (1915 – 2000), Edwin Morgan (1920 – 2010), and Miroslav Holub (1923 – 1998), is preceded by a literature survey and an initial theoretical chapter. This initial part of the thesis outlines the interdisciplinary history of the academic subject of poetry and science, addressing, amongst other things, the challenges presented by the episodes known as the ‘two cultures' and the ‘science wars'. Seeking to offer a perspective on poetry and science more aligned to scientific materialism than is typical in the interdiscipline, a systemic challenge to Thomas Kuhn's The Structure of Scientific Revolutions (1962) is put forward in the first chapter. Additionally, the founding work of poetry and science, I. A. Richards's Science and Poetry (1926), is assessed both in the context in which it was written, and from a contemporary viewpoint; and, as one way to understand science in poetry, a theory of the creative misreading of science is developed, loosely based on Harold Bloom's The Anxiety of Influence (1973). The detailed study of science in poetry commences in Chapter II with Hugh MacDiarmid's late work in English, dating from his period on the Shetland Island of Whalsay (1933 – 1941). The thesis in this chapter is that this work can be seen as a radical integration of poetry and science; this concept is considered in a variety of ways including through a computational model, originally suggested by Robert Crawford. The Australian poet Judith Wright, the subject of Chapter III, is less well known to poetry and science, but a detailed engagement with physics can be identified, including her use of four-dimensional imagery, which has considerable support from background evidence. Biology in her poetry is also studied in the light of recent work by John Holmes. In Chapter IV, science in the poetry of Edwin Morgan is discussed in terms of its origin and development, from the perspective of the mythologised science in his science fiction poetry, and from the ‘hard' technological perspective of his computer poems. Morgan's work is cast in relief by readings which are against the grain of some but not all of his published comments. The thesis rounds on its theme of materialism with the fifth and final chapter which studies the work of Miroslav Holub, a poet and practising scientist in communist-era Prague. Holub's work, it is argued, represents a rare and important literary expression of scientific materialism. The focus on materialism in the thesis is not mechanistic, nor exclusive of the domain of the imagination; instead it frames the contrast between the original science and the transformed poetic version. The thesis is drawn together in a short conclusion.
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