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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the 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.
91

Développement et utilisation d'une puce de capture d'exons pour l'étude à large spectre de régions génomiques divergentes entre populations sympatriques de grand Corégone (Coregonus clupeaformis)

Gagnon-Hébert, François Olivier 19 April 2018 (has links)
Le processus biologique fondamental que représente la spéciation permet l’émergence d’une diversité fulgurante sur Terre. L’un des défis qui se posent actuellement pour les biologistes évolutionnistes est de comprendre les mécanismes moléculaires fondamentaux qui sous-tendent l’expression de cette diversité observée en milieu naturel. Advenant la colonisation d’un nouvel environnement par une espèce donnée, ces mécanismes peuvent se mettre en place rapidement afin de permettre une exploitation différentielle et indépendante des niches écologiques disponibles. La divergence entre populations exploitant différentes niches s’exprime alors, au niveau génétique, par l’établissement de barrières au flux génique de façon hétérogène à l’intérieur des génomes. La situation évolutive du grand corégone en Amérique du Nord correspond précisément à ce contexte. En effet, on retrouve en milieu lacustre des populations sympatriques de deux écotypes, soit la forme normale benthique et la forme naine limnétique, qui démontrent des signes évidents de divergence morphologique et génétique. Dans le cadre de cette récente divergence entre écotypes, nous avons utilisé les plus récents développements biotechnologiques afin d’identifier et caractériser les régions génomiques fortement différenciées entre écotypes de grand corégone. Les objectifs de la présente étude étaient de i) mettre au point une bio-puce de capture ciblée d’ADN génomique, ii) d'hybrider de l’ADN génomique de plusieurs corégones appartenant aux populations sympatriques à l’aide de la puce conçue, iii) d’assembler et annoter un maximum de gènes capturés et iv) de caractériser la nature et l’ampleur des régions génomiques de divergence entre nains et normaux. L'utilisation de cette technique a permis de capturer et d'assembler avec précision 2 728 gènes (~10% du génome) afin de procéder à une étude à large spectre des différences génétiques entre les deux écotypes. Ce travail a permis d'identifier 267 marqueurs SNP, situés dans 210 gènes, fortement différenciés et potentiellement impliqués dans la divergence écologique qui s’exerce entre écotypes de grand corégone. Les résultats suggèrent que la régulation de l’expression des gènes et un ensemble de mutations, chacune de faible effet, interviennent tôt dans le processus de spéciation chez le corégone, par opposition aux mutations structurales qui modifient la séquence codante des gènes. / The fundamental process of speciation allows the emergence of an astonishing diversity on Earth. One of the main challenges in evolutionary biology is to understand and document the fundamental molecular mechanisms underlying this diversity observed in nature. The establishment of these mechanisms can be extremely rapid when a species colonizes new environments, which gives birth to niche specialization. On the genetic level, this population divergence appears by the emergence of heterogeneous barriers to gene flow in the genome. Lake Whitefish species pairs in North America represent a good model to study the ongoing process of speciation given its particular evolutionary situation. Various lakes in northeastern North America harbor sympatric populations of dwarf (limnetic) and normal (benthic) whitefish showing clear signs of morphological and genetic divergence. In this study, we have taken advantage of recent biotechnological developments in order to identify and document genomic regions of divergence between whitefish ecotypes. The objectives were to i) develop an exon capture chip, ii) enrich and capture genomic regions from multiple samples in natural populations, iii) assemble and annotate a maximum of captured genes and, ultimately, iv) document the extent of genetic differentiation between whitefish ecotypes. This new approach available with the technology of sequence capture allowed us to specifically capture and assemble 2,728 genes (~10% of the genome) to document on a large scale the extent of genetic differentiation between both ecotypes. In total, 267 SNP loci, located in 210 genes, were significantly divergent. This vast array of genes associated to many different biological processes potentially and partly explains the ecological divergence between whitefish ecotypes. Results suggest a greater role of regulation of gene expression and the role of many changes, each of small effect, as explaining early divergence between dwarf and normal whitefish, compared to functional mutations in the protein coding regions.
92

Paganini au piano : Franz Liszt, Ferruccio Busoni, Michael Zadora, Mark Hambourg, Ignaz Friedman et la « grande manière » / Paganini at the piano : Franz Liszt, Ferruccio Busoni, Michael Zadora, Mark Hambourg, Ignaz Friedman and the « grand manner »

Filipec, Goran 15 November 2018 (has links)
Dans l’art de la musique instrumentale, il y a certainement eu des moments de développement extraordinaires. La plus grande révolution dans le domaine du violon aura probablement été Paganini, avec ses innovations dans le cadre de la technique, de la texture et des effets timbriques du violon. Dans le domaine du piano, Liszt, suite à sa rencontre avec le violon assimilateur et imitateur du Génois, reforma son jeu et reconçut le pianisme de l’époque. Dans cette mission, il fut accompagné par des améliorations techniques à l’instrument. L’art du jeu du piano, qui hérita de Paganini le côté assimilateur et imitateur, qui abandonna le salon et s’installa dans les grandes salles, fut reconnu comme la « grande manière » ou le « grand style ». Ces termes, provenant principalement de l’art de Liszt, qui fut apparemment son premier représentant, se réfèrent à un style pianistique particulier, basé sur de grands effets acoustiques et de nouvelles techniques d’exécution. Le corpus de l’étude est constitué des œuvres de Liszt d’après Paganini, telles que les Études d’exécution transcendante d’après Paganini, les Grandes Études de Paganini, La Grande Fantaisie de bravoure sur La Clochette et les œuvres en relation avec Paganini des générations suivantes de pianistes de la « grande manière ». Celles-ci incluent les versions des études de Liszt réalisées par Ferruccio Busoni, son Introduzione e Capriccio (Paganinesco), les arrangements des Caprices de Paganini par Michael Zadora, les Variations sur un thème de Paganini de Mark Hambourg et les Études d’après un thème de Paganini op. 47b d’Ignaz Friedman. L’étude tente de tracer la « grande manière » dans les formes pianistiques appliquées dans les œuvres citées ainsi que d’identifier les particularités du « pianisme » des auteurs concernés. / In the art of instrumental music there were moments of extraordinary evolution. The greatest revolution in the domain of the violin was probably the appearance of Paganini and his innovations in the technique, the texture of violin writings and the exploitation of the timbrical effects of the instrument. In the domain of the piano, Liszt, after having heard the assimilating and imitating violin of the Genovese, reformed his playing and transformed the pianism of his époque. In that mission, he was accompanied by technical improvements of the instrument. The art of piano playing, which inherited from Paganini the assimilating and imitating tendencies and left the salon in favor of big halls, was recognized as the “grand manner” or the “grand style” grand style’, first represented by Liszt. These terms, mainly originating from the conceptual grandeur of his art, refer to a particular pianistic style, based on big acoustic effects and new techniques of execution. The corpus of the present study is constituted by the works after Paganini by Liszt, including the Études d’exécution transcendante d’après Paganini, the Grandes études de Paganini, La Grande fantaisie de bravoure sur La Clochette, and the works related to Paganini of the following generations of pianists of the « grand manner”. These include the arrangements of Liszt’s studies of Busoni, the Introduzione e Capriccio paganinesco, the Variations sur un thème de Paganini of Mark Hambourg and the Paganini-Studies op. 47b of Ignaz Friedman. The study tempts to trace the “grand manner” in the pianistic forms applied in the cited works, and to identify the specificities of the pianism of the concerned authors.
93

Grand Prix České Republiky / Grand Prix Czech Republic

Pleva, Dominik January 2011 (has links)
Major case of this project is design of new headquarters of Czech Grand prix in Brno. As an design I worked with car aerodynamic design and technology. With ideas of speed, hi technology etc. was designed whole project.
94

Génomique de la spéciation chez le Grand Corégone (Coregonus clupeaformis) : caractérisation des bases génomiques associées à la différenciation phénotypique

Rougeux, Clément 16 April 2019 (has links)
L'évolution répétée et indépendante de la différenciation phénotypique entre espèces divergentes, suggérant des pressions sélectives similaires, constitue un contexte propice à l'étude de l'architecture génomique de la spéciation parallèle. L'objectif principal de cette thèse est d'apporter des éléments de réponses concernant les bases génomiques impliquées dans la différenciation phénotypique, et leur influence sur l’évolution de la divergence entre deux complexes d'espèces apparentés, le Grand Corégone (Coregonus clupeaformis) et le Corégone Lavaret (C. lavaretus). Plus précisément, il était nécessaire d'élucider l'origine du polymorphisme de chacune des populations, le rôle de cette variation génétique, son maintient durant la divergence et la différenciation phénotypique entre paires d'espèces. Une analyse génomique a permis de réaliser des inférences démographiques historiques, mettant en évidence la contribution simultanée de processus démographiques et sélectifs qui ont façonné les paysages génomiques de différenciation entre paires d'espèces. Ensuite, une analyse transcriptomique a permis d'identifier des bases polygéniques partagées impliquées dans la différenciation phénotypique parallèle entre paires d'espèces. De plus, ces bases polygéniques indiquent une forte rétention du polymorphisme ancestral sous l’action de la sélection divergente. Finalement, un parallélisme de régions d’ADN différentiellement méthylées entre espèces a été identifié. Bien que cette méthylation repose sur des bases génomiques, ces régions différentiellement méthylées sont associées à une différenciation transcriptionnelle entre espèces des complexes d'espèces du Corégone Lavaret et du Grand Corégone. Ces travaux montrent que la sélection naturelle est contrainte par certains génotypes permettant d'acquérir un parallélisme phénotypique de façon indépendante, et agir sur du polymorphisme ancestral, notamment dans un contexte de spéciation parallèle. Enfin, cette thèse permet de lever le voile et de contribuer à la compréhension des mécanismes génomiques associés à la divergence adaptative pouvant mener à la spéciation écologique, notamment en utilisant une approche intégrative. / Repeated evolution of phenotypic differentiation between diverging species pairs provides an ideal context for the study of the genomic architecture of parallel speciation. The main objective of this thesis is to provide evidence concerning the genomic bases involved in phenotypic differentiation, and their influence on the evolutionary potential of species complexes belonging to two related lineages, the Lake Whitefish (Coregonus clupeaformis) and European Whitefish (C. lavaretus). Specificaly, it is necessary to elucidate the origin of the genetic polymorphism of each population from both whitefish lineages, and to which extend this polymorphism was involved in the genetic divergence and phenotypic differentiation between species pairs. A genome-wide analysis allowed to infer the divergence history combining the effects of historical demograhy and selective pressure that collectively shape the genomic landscape of differentiation between species pairs. Then, transcriptomic analyses revealed parallel polygenic bases involved in the phenotypic differentiation of species pairs, and such genes were enriched in shared ancestral polymorphism. Finaly, a parallel differential methylation level has been identified between species. Although this methylation is genomicaly based, these differentially methylated regions are associated with a transcriptional differentiation between the limnetic and benthic species. This work shows that selection is constrained by some genotypes which could lead to an independent parallel phenotypic aquisition, but also act on the maintainance of ancestral genetic polymorphism, particularly in a context of parallel speciation. This thesis allows to highlight and to contribute to the understanding of the genomic mechanisms generating biodiversity, notably by using an integrative approach.
95

Evaluation of unconfined aquifer parameters using a successive line relaxation finite difference model.

Rebuck, Ernest Charles,1944- January 1972 (has links)
A finite difference model was developed specifically for analyzing the Grand Island, Nebraska aquifer test. Time-drawdown data for the aquifer test were fitted by least squares to an exponential type equation. To facilitate calibration of the model, interpolated distance-drawdown profiles also were fitted to an exponential type equation. The treatment of aquifer boundaries and the assumption of isotropic aquifer conditions affected the model computed water table profile. The effect was significant enough as to defy making accurate estimates of saturated hydraulic conductivity and specific yield. When the analysis was extended to long time periods of discharge, problems with the boundaries, particularly the distance to the lateral constant head boundary, led to unrealistic estimates of pumping level. The finite difference technique has its greatest application as a research method for analyzing short-duration aquifer tests provided that the aquifer conditions are well defined, measurements of pumping level are available and drawdown measurements have been secured for at least two observation wells within close proximity of the discharge well. Because of difficulties in maintaining convergence and model stability, the finite difference model reviewed in this study is too cumbersome to be considered a practical, field method for the analysis of unconfined aquifer parameters.
96

Yanawant: Paiute Places and Landscapes in the Arizona Strip Volume One of the Arizona Strip Landscapes and Place Name Study

Stoffle, Richard W., Van Vlack, Kathleen, Carroll, Alex, Chmara-Huff, Fletcher, Martinez, Aja January 2005 (has links)
This report is the product of a study funded by the Bureau of Land Management (BLM) entitled, The Arizona Strip Cultural Landscape and Place Name Study. The study has five main objectives: (1) to provide an overview of American Indian Cultural Landscapes and their relevance for federal agency practices, (2) to describe the ethnographic, historic, and cultural bases for Southern Paiute communities’ access to particular sites within the Arizona Strip, (3) to identify Southern Paiute place names, trails, and stories associated with selected cultural landscape sites within the Arizona Strip, (4) to include descriptions of the cultural significance of natural resources and physical environmental features at selected cultural landscape sites, and (5) to determine the need for future studies based on gaps identified in the historic and ethnographic record. The study is intended to serve as a foundation for identifying and managing Native American resources, cultural sites and cultural landscapes on the Arizona Strip. This report is focused on direct interviews with Southern Paiute people at places in the Arizona Strip. These locations were chosen to represent kinds of places that are culturally significant to Southern Paiute people. These include rock art sites, archaeology sites, springs, rivers, canyons, mountains, lava flows, and areas with special vistas. These places were chosen by representatives of the involved tribes, Arizona Strip BLM staff, and the project director at the Bureau of Applied Research in Anthropology at the University of Arizona. This is a first study of its kind funded by the Arizona Strip and so a study goal was to see what kinds of contemporary cultural importance would be assigned by Indian people to kinds of places. It was thus impossible to go to all places of cultural significance in the Arizona Strip so the study lays a foundation for more comprehensive studies in the future.
97

LDK miškų ūkis XVI a / The forestry of the Grand Duchy of Lithuania in the sixteenth century

Daukšas, Mantas 10 June 2011 (has links)
Lietuva visais laikais garsėjo savo miškais. Nepražengiamos girios stebindavo į mūsų kraštą negausiai užklydusius svetimšalius. Savo prisiminimuose apie Lietuvos Didžiąją Kunigaikštystę jie sutartinai akcentuodavo stulbinamą girių didumą bei žvėrių įvairovę. Iš visų miško teikiamų dovanų žmogui galėtume išskirti medžius. Mediena buvo nepamainomas šilumos šaltinis, pagrindinė statybinė medžiaga. XVI amžiuje, Vakarų Europoje smarkiai išaugus medienos gaminių poreikiui, miškas, jo gaminiai Lietuvoje po truputį tapo viena iš pagrindinių eksporto prekių. / Lithuania has always been famous for own forests. Rarely foreigners who for some reason had a possibility to see our nature were surprised by its heavy forests. In the memories of Grand Ducky of Lithuania they were always highlighting the shocking immensity of the forests and the big variety of animals. Out of all the gifts offered by the forest we should distinguish the trees. The wood was invaluable source of heat as well as the main building material. In the sixteenth century in Western Europe the demand for wood products increased which led to increase of Lithuania‘s wood export. Wood became the main export product.
98

Proton decay matrix elements from lattice QCD

Cooney, Paul January 2010 (has links)
We present results for the matrix elements relevant for proton decay in Grand Unified Theories (GUTs), using two methods. In the indirect method, we rely on an effective field theory description of proton decay, where we need to estimate two low energy constants. We then relate these low energy constants to the proton decay matrix elements using leading order chiral perturbation theory. In the direct method, we calculate the required matrix elements directly; this is computationally more expensive, but the calculation has no systematic error from the use of chiral perturbation theory. The calculations are performed with 2+1 flavors of domain wall fermions on lattices of size 163 × 32 and 243 × 64 with a fifth dimension of length 16. We work at fixed inverse lattice spacing, a−1 = 1.73(3) GeV, leading to physical volumes of (1.8 fm)3 and (2.7 fm)3 for the 163 × 32 and 243 × 64 lattices respectively. In the first four chapters we present the background theory. We start with a brief review of the standard model and the motivation for GUTs. We show that GUTs must lead to proton decay, and that the proton lifetime is an experimentally testable prediction which can be used to constrain GUT parameters, or rule out classes of GUT which predict a minimum lifetime shorter than the experimental minimum bound. We then review continuum and lattice QCD, including outlines of the lattice methods used to calculate the proton decay matrix elements. In the last three chapters we present the results and analysis. We calculate the nucleon and pion two–point correlation functions, and determine their ground state masses and amplitudes. These quantities will then be used to calculate the matrix elements using the indirect and direct methods outlined above. The matrix elements can then be combined with experimental bounds on the proton lifetime to bound parameters of individual GUTs.
99

Unification in Particle Physics

Jansson, Henrik January 2016 (has links)
During the twentieth century, particle physics developed into a cornerstone of modern physics, culminating in the Standard Model. Even though this theory has proved to be of extraordinary power, it is still incomplete in several respects. It is our aim in this bachelor thesis to discuss some possible theories beyond the Standard Model, the main focus being on Grand Unified Theories, while also taking a look at attempts of further unication via discrete family symmetry. At the heart of all these theories lies the concept of local gauge invariance, which is introduced as a fundamental principle, followed by an overview of the Standard Model itself. No theory has so far managed to unify all elementary particles and their interactions, but some interesting features are highlighted. We also give a hint at some possible paths to go in the future in the quest for a unication in particle physics. / Under 1900-talet utvecklades partikelfysiken till en av de fundamentala teorierna inom fysiken, och kom att sammanfattas i den s.k. Standardmodellen. Även om denna modell rönt exceptionella framgånger vad gäller beskrivningen av elementarpartiklar och deras växelverkan, är den fortfarande ofullständig på flera sätt. Syftet med denna kandidatuppsats är att diskutera möjliga teorier bortom Standardmodellen såsom Storförenande Teorier och diskreta familjesymmetrier vars avsikt är att koppla samman de tre familjerna av fermioner i Standardmodellen. Men först introduceras idén om lokal gaugeinvarians, vilken ligger till grund for dessa teorier, varpå en översikt av Standardmodellen följer. Ingen teori har ännu lyckats ge en helt tillfredsställande bild av elementarpartiklar och deras interaktion, men en del intressanta egenskaper hos föreslagna teorier belyses i denna uppsats. Slutligen ges en del spekulativa förslag på väger att gå i framtida försök till föreningar inom partikelfysiken.
100

Säkerhetspolitisk bristvara? : en kartläggning av svensk säkerhetsstrategi efter Försvarsbeslut 15

Jändel, Kristoffer January 2017 (has links)
This study examines the Swedish defense bill from 2015 to work out if the content can be considered as an official national security strategy of Sweden and if it can be considered a balanced strategy.  The main conclusion of the study is that the defense bill contains information about the basic strategic components of ends, means, ways and context at the security strategy level. What is lacking is an analysis of the means available to Sweden. The study find that the strategy of the bill contains the elements of a security strategy. There is need of descriptions and analysis of the Swedish interior strategic context as well as the political, diplomatic, economic and strategic communications means available, and how they are to be deployed by the Swedish government to produce desired ends. The balance between end, ways, means and context in the Swedish security strategy is varying from reasonably good to non-existing, depending on the measured area.

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