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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.
271

Les effets du dalcetrapib, un inhibiteur de la protéine de transfert des esters de cholestérol (CETP), sur la structure et la fonction des lipoprotéines de haute densité (HDL) dans l’étude dal-PLAQUE2

Beaudet, Marie-Lou 10 1900 (has links)
No description available.
272

Utilisation des isotopes stables et radiogéniques du strontium pour tracer la provenance des bois : application à des épaves sous-marines / Use of stable and radiogenic strontium isotopes to trace the origin of woods : application to wood from shipwrecks

Hajj, Fadi 14 November 2017 (has links)
Au début des temps modernes (16ème - 18ème siècles), la construction de grands navires était primordiale pour le développement des rencontres culturelles dans ce qui est devenu l'âge de la découverte et de l'expansion européenne. L’Espagne était une des grandes puissances de l’époque. Le projet européen « ForSEAdiscovery » cherche dans ce contexte à répondre aux questions clés suivantes : les ressources forestières ibériques de l’époque soutenaient-elles la demande croissante de bois, ou bien ce bois était-il importé d’autres pays ? Si ces bois ne provenaient pas de l’Espagne, comment les réseaux de commerce étaient-ils organisés ? Ce projet aborde ces questions à travers un programme de recherche multidisciplinaire et innovant pour améliorer la compréhension de notre passé historique et de notre patrimoine culturel, et développer notre connaissance sur l'utilisation passée des ressources en bois pour la construction navale. L'objectif de cette thèse, qui s’insère dans ce projet, est d’identifier la provenance des bois utilisés dans la construction navale ibérique en utilisant des traceurs géochimiques. L’hypothèse est que les arbres se développant sur des roches et des sols contrastés possèdent des signatures géochimiques spécifiques héritées des roches. Les signatures isotopiques en strontium (87Sr/86Sr) peuvent notamment être des indicateurs de provenance géographique. Dans ce contexte, la démarche suivie dans la thèse a consisté à caractériser la signature isotopique en Sr dans des bois d'épaves de bateaux et dans les bois d’arbres actuels, les sols et roches prélevés dans les principaux peuplements forestiers espagnols pointés comme lieux de production des bois entre le 16ème - 18ème siècles. Les signatures en δ88/86Sr, traceur peu connu encore, ont également été caractérisées dans les échantillons. Les types et les âges des roches ont été caractérisés et les liens entre les rapports isotopiques 87Sr/86Sr et δ88/86Sr dans les roches, sols et arbres ont été étudiés sur les sites espagnols échantillonnés. La signature locale des sites espagnols potentiels de provenance de bois a été déterminée. Nos résultats mettent en évidence que le rapport isotopique 87Sr/86Sr dans les arbres reflète la signature de la fraction échangeable des sols sur lesquels ils croissent alors que le δ88/86Sr est affecté par le fractionnement, les isotopes légers (86Sr) étant préférentiellement incorporés dans les arbres laissant la fraction échangeable du sol enrichie avec les isotopes lourds (88Sr). Ce fractionnement observé pour les chênes, n’est pas marqué dans le bois des pins suggérant que le fractionnement isotopique durant le transfert du Sr entre le sol et l’arbre est dépendant de l’espèce. La contamination des bois d’épaves par les éléments marins a été identifiée. Le Sr marin se retrouve notamment sous forme adsorbée ou dans la structure des minéraux précipités dans les bois immergés. Différentes expériences d’extractions ont été testées et un protocole adapté a été développé pour extraire les éléments marins et retrouver la signature originelle du bois archéologique. Nous avons réussi à valider un protocole d’extraction et retrouver la signature originelle d’un échantillon de bois d’épave. Ce résultat souligne le potentiel et l’importance d’une nouvelle méthode combinant 87Sr/86Sr et δ88/86Sr pour des futures études de provenance de bois ou autres matériaux. Cependant, nos résultats indiquent également que beaucoup de nos échantillons de bois archéologiques n’ont pas conservé leur Sr originel. Partant de ce constat, des préconisations sont proposées pour améliorer la possibilité d’utilisation de ce traceur dans les études futures de provenance de bois archéologiques sous-marins / In the Early Modern Age (16th - 18th centuries), the construction of ocean-going ships was paramount to the development of cultural encounters in what became the Age of Discovery and European expansion. Spain was one of the biggest forces of that time. The European project “ForSEAdiscovery” seeks answers in this context to the following key questions: Could Spanish forest resources sustain the increasing demand of timber, or were the wood imported from elsewhere? If Spanish forests were not the only wood supplier, how were the trade networks organized? This project will address these questions through a multidisciplinary and innovative training research program to improve the understanding of our historical past, our cultural heritage, and our knowledge of the use of resources for shipbuilding. The objective of this PhD thesis, taking part of this project, is to identify the provenance of the Iberian shipbuilding wood using geochemical tracers. The hypothesis is that trees growing on contrasted rocks and soils have specific geochemical signatures, which can be an indicator of geographic provenance. In this context, the Sr isotopic signature (87Sr/86Sr) was characterized in shipwreck wood samples and wood from living trees, soils and rocks collected from the Spanish forest stands indicated as potential source of wood between the 16th - 18th centuries. The δ88/86Sr signatures were also characterized in the samples. The rock types and ages were characterized at the selected sites and the link between the 87Sr/86Sr and δ88/86Sr in rocks, soils and trees was studied on the sampled Spanish sites. The local signature of Spanish potential sites was determined for provenance of wood. Our results indicate that 87Sr/86Sr isotope ratios in trees reflect the signature of the corresponding soil exchangeable pool while δ88/86Sr was shown to be affected by mass-dependent fractionation with trees taking up lighter (86Sr) isotopes, leaving the soil exchangeable pool enriched with the heavier isotopes (88Sr). This fractionation observed for oak trees, was not found in pines suggesting that the isotopic fractionation during tree uptake is species dependent. The contamination of wood from shipwrecks by seawater elements was identified. Marine Sr was found to be adsorbed on the wood or included in the precipitated minerals in the waterlogged wood. Several extraction experiments were tested and an adapted protocol was developed to extract the seawater elements and retrieve the original signature of the archaeological wood. We succeeded to validate an extraction protocol and retrieve the original signature of one wood sample. This result underline the potential and importance of a new method combining 87Sr/86Sr and δ88/86Sr values for future provenance studies on wood or other materials. However, our results also indicated that most of our shipwreck wood samples did not conserve their original Sr. Therefore, preconizations were suggested in order to extend the use of this tracer in future provenance studies on archaeological wood from shipwrecks
273

RNA modifications and processing in cell homeostasis and in response to oxidative stress

Gkatza, Nikoletta A. January 2018 (has links)
RNA modifications and processing events are important modulators of global gene expression. Genomic mutations in the RNA methylase NSun2 and the alternative splicing factor Srsf2 are linked to neurological disorders and cancer in humans, respectively. NSun2 methylates cytosine-5 in most tRNAs and, to a lesser extent, other ncRNAs and mRNAs. Srsf2 is a critical component of the spliceosome and interacts with abundant ncRNAs that are methylated by NSun2. However, how precisely these processes effect homeostasis is largely unexplored. Therefore, the main aims of my PhD were (1) to dissect the molecular mechanisms of NSun2-mediated RNA methylation pathways that regulate cell survival under normal conditions and in response to oxidative stress, and (2) to investigate the importance of Srsf2 in stem cells using skin as a model system. In the context of RNA modifications, firstly I described how NSun2-expressing cells enrich for transcripts related to enhanced cell survival. Subsequently, by metabolically profiling wildtype and patient-derived dermal fibroblasts carrying loss-of-function mutations in the NSUN2 gene, I showed that the absence of NSun2 is synonymous to an energy-saving, low-translating and stressed cellular state. I further confirmed that lack of NSun2 was sufficient to instigate a cellular stress response, by monitoring BIRC5, a member of the inhibitor of apoptosis family. To further answer whether lack of NSun2 enhanced the susceptibility of patient cells to external stress stimuli, I next exposed them to oxidative stress and measured transcriptional and translational changes. I discovered that NSun2 is required to adapt global protein synthesis to the stress response, while NSun2-depleted cells failed to do so. This was concurrent with NSun2-depleted cells enriching for transcripts related to mRNA degradation and negative regulators of protein translation in response to stress. Generally, since loss of NSun2-driven methylation in tRNAs triggers their cleavage into small ncRNA fragments by angiogenin, I asked how angiogenin or tRNA-derived ncRNAs affect translation levels. In the presence of NSun2, angiogenin alone did not reduce global protein synthesis, yet tRNA fragmentation was required to modulate translation levels. Finally, to uncover how the lack of NSun2 influenced tRNA cleavage and methylation patterns in response to stress, I exposed wildtype and patient cells to sodium arsenite and measured the abundance of tRNA-derived fragments and occurrence of methylation events. With this I discovered unique tRNA fragmentation patterns and global RNA methylation profiles for wildtype and NSun2-depleted cells, that can account for the underlying molecular and phenotypical differences in response to stress. In the context of alternative splicing, and since the cellular functions of Srsf2 are largely unknown, I explored its role in cellular survival and differentiation. By conditionally deleting SRSF2 in two different stem cell populations of the mouse epidermis, I observed significant thickening of the epidermis, altered expression of cell proliferation and stem cell differentiation markers, and distorted hair follicle structures. Moreover, I demonstrated that lack of Srsf2 promotes skin regeneration following injury, thus strongly indicating that Srsf2 is required for normal skin development and regeneration after injury. In summary, my research suggests that NSun2-mediated RNA methylation pathways orchestrate transcriptional and translational programmes in response to external stress stimuli, and my studies are the first to show that the alternative splicing factor Srsf2 is required for stem cell differentiation in skin.
274

Forensic medicine in Scotland, 1914-39

Duvall, Nicholas January 2013 (has links)
This thesis examines the practice of forensic medicine in Scotland in the period 1914 to 1939. This was a time of significant dynamism for the discipline, in which it enjoyed a high public profile and played an important role in the investigation of crime. The project focuses in particular on medico-legal practice at an elite level, based in specialist departments in the universities of Edinburgh and Glasgow. As well as producing a significant amount of research and textbook material, and thus constituting authorities within the discipline, representatives of these institutions gave expert evidence in a number of high-profile trials. Thus, an examination of their work can show how medico-legal knowledge was constructed, presented and challenged. To this end, four main areas of forensic medical practice are analysed, including the post-mortem examination, the laboratory analysis of trace evidence, the investigation of shootings and the use of photography. The development of the techniques contained within these categories is charted, as is the range of situations to which they were applied and the various ways in which their use was challenged in court by hostile legal counsel. Sources including textbooks and journal articles, medical case reports, photograph albums and trial transcripts are used. A fifth section explores an area of the public face of the discipline, specifically the popular output of two of its most famous practitioners, Sydney Smith and John Glaister Jr. Both produced memoirs and newspaper serials after retirement. These are used to explore the ways they reflected on their careers and spun their legacies, portraying themselves as impartial servants of science and justice. The thesis argues that the place of forensic medicine in wider institutional, investigative and geographical networks was central to its existence. The discipline collaborated extensively, both with representatives of other areas of the medical profession and with external authorities, professions and trades. Means of communication, such as written reports and samples taken at autopsy, allowed experts in the universities to lend their expertise to the non-specialists in peripheries by providing expert opinions based on materials sent to them. The scrutiny of post-mortem reports produced by peripheral generalists allowed medico-legists’ expertise to be spread over a wide geographical area. The thesis also reflects on the ways in which medico-legists guarded against error. Techniques derived from other areas of medicine and science were not adopted for use in court until their reliability could be demonstrated satisfactorily, and controls and standards were built in to procedures.
275

Arc Crust-Magma Interaction in the Andean Southern Volcanic Zone from Thermobarometry, Mineral Composition, Radiogenic Isotope and Rare Earth Element Systematics of the Azufre-Planchon-Peteroa Volcanic Complex, Chile

Holbik, Sven P 23 May 2014 (has links)
The Andean Southern Volcanic Zone (SVZ) is a vast and complex continental arc that has been studied extensively to provide an understanding of arc-magma genesis, the origin and chemical evolution of the continental crust, and geochemical compositions of volcanic products. The present study focuses on distinguishing the magma/sub-arc crustal interaction of eruptive products from the Azufre-Planchon-Peteroa (APP 35°15’S) volcanic center and other major centers in the Central SVZ (CSVZ 37°S - 42°S), Transitional SVZ (TSVZ 34.3-37.0°S), and Northern SVZ (NSVZ 33°S - 34°30’S). New Hf and Nd isotopic and trace element data for SVZ centers are consistent with former studies that these magmas experienced variable depths of crystal fractionation, and that crustal assimilation is restricted to the lower crustal depths with an apparent role of garnet. Thermobarometric calculations applied to magma compositions constrain the depth of magma separation from mantle sources in all segments of the SVZ to(70-90 km). Magmatic separation at the APP complex occurs at an average depth of ~50 km which is confined to the mantle lithosphere and the base of the crust suggesting localized thermal abrasion both reservoirs. Thermobarometric calculations indicate that CSVZ primary magmas arise from a similar average depth of (~54 km) which confines magma separation to the asthenospheric mantle. The northwards along-arc Sr-Nd-Hf isotopic data and LREE enrichment accompanied with HREE depletion of SVZ mafic magmas correlates well with northward increasing crustal thickness and decreasing primary melt separation from mantle source regions indicating an increased involvement of lower crustal components in SVZ magma petrogenesis. The study concludes that the development of mature subduction zones over millions of years of continuous magmatism requires that mafic arc derived melts stagnate at lower crustal levels due to density similarities and emplace at lower crustal depths. Basaltic underplating creates localized hot zone environments below major magmatic centers. These regions of high temperature/partial melting, and equilibration with underplated mafic rocks provides the mechanism that controls trace element and isotopic variability of primary magmas of the TSVZ and NSVZ from their baseline CSVZ-like precursors.
276

Problematika přiměřeného protiplnění při výkupu akcií v právních systémech České a Slovenské republiky / The issue of adequate consideration by squeeze out in the legal systems of the Czech Republic and Slovakia

Šimo, Peter January 2008 (has links)
In the first chapter I define the concept of reasonable consideration by squeeze out on the basis of the Czech Republic, Slovakia and the European Union. In the second chapter are compared basis laws which regulate the purchase of participating securities in the Czech Republic and Slovakia, together with the EU legislation. The third chapter deals with the legislation for the surveys in compared countries. The fifth chapter deals with economic aspects of the determination of adequate consideration in connection with the views of experts in the field. The sixth chapter provides concrete examples of the determination of reasonable consideration in the Czech and Slovak Republic, including the major differences. The final chapter compares legislation in the Czech and Slovak Republics, and proposes ways to eliminate existing deficiencies.
277

Spider III: A multi-agent-based distributed computing system

Ruan, Jianhua, Yuh, Han-Shen, Wang, Koping 01 January 2002 (has links)
The project, Spider III, presents architecture and protocol of a multi-agent-based internet distributed computing system, which provides a convenient development and execution environment for transparent task distribution, load balancing, and fault tolerance. Spider is an on going distribution computing project in the Department of Computer Science, California State University San Bernardino. It was first proposed as an object-oriented distributed system by Han-Sheng Yuh in his master's thesis in 1997. It has been further developed by Koping Wang in his master's project, of where he made large contribution and implemented the Spider II System.
278

Virtualizace vstupních a výstupních operací v počítačových sítích / Virtualization of I/O Operations in Computer Networks

Remeš, Jan January 2017 (has links)
This work deals with virtualization of computer systems and network cards in high-speed computer networks, and describes implementation of the SR-IOV virtualization technology support in the COMBO network card platform. Various approaches towards network card virtualization are compared, and the benefits of the SR-IOV technology for high performance applications are described. The work gives overview of the COMBO platform and describes design and implementation of the SR-IOV technology support for the COMBO platform. The work concludes with measurement and analysis of the implemented technology performance in virtual machines. The result of this work is the COMBO cards' support for the SR-IOV technology, which makes it possible to use them in virtual machines with wire-speed performance preserved. This allows future COMBO cards to be used as accelerators in the networks utilizing the Network Function Virtualization.
279

Přímá volba slovenského prezidenta ve středoevropském kontextu / Direct election of Slovak president in central European context

Môcik, Tibor January 2016 (has links)
The topic of this diploma thesis is direct elections of the President of Slovak Republic in context of other Central European countries - particularly Czech Republic and Poland. The subject of my analysis were selected aspects of presidential election, which I analyzed in the third chapter (in case of Slovakia), dedicated to direct elections of Slovak president in 1999, 2004 and 2009; and in the fourth chapter, which is dedicated to last direct election. Among analyzed aspects (in case of Slovak presidential election) a trend of declining interest in the first round of elections was confirmed; also sooner claiming of candidacy, compared with previous elections. The latter fact is connected with longer and longer pre-election campaign, which is also more and more personal and offensive. The ratio of partisan and non-partisan candidates was in all elections about the same (approx. 3:2 in favor of partisan candidates). In the fifth chapter of the thesis I analyzed these aspects in case of direct presidential elections in Poland and Czech Republic. Then, I compared them. According to analysis, women in Poland almost were not standing for president at all (there were even fewer women candidates than in Slovakia), but in Poland we can see much higher number of very prominent candidates (especially former...
280

Studium relaxačních feroelektrických látek se spontánními polárními nanooblastmi / Studies of Relaxor Ferroelectrics with Spontaneous Polar Nanoregions

Ondrejkovič, Petr January 2017 (has links)
Title: Studies of Relaxor Ferroelectrics with Spontaneous Polar Nanoregions Author: Petr Ondrejkovič Institute: Institute of Physics of the Czech Academy of Sciences Supervisor: Ing. Jiří Hlinka, Ph.D., Institute of Physics of the Czech Academy of Sciences Abstract: The thesis is devoted to relaxor ferroelectrics with spontaneous polar nanoregions. We have investigated one of the canonical representatives, uniaxial strontium barium niobate, by means of neutron scattering, and also performed computer simulations with a model of a uniaxial ferroelectric with point defects. Neutron scattering studies of strontium barium niobate single crystals under a defined sequence of thermal and electric field treatments elucidate nature of distinct components of its transverse diffuse scattering. These components are associated mainly with the static ferroelectric nanodomain structure and the dynamic order-parameter (polarization) fluctuations. Moreover, high-resolution neutron backscattering experiments allowed us to resolve characteristic frequencies of the order-parameter fluctuations and prove that this component is caused by the same polar fluctuations that are responsible for the Vogel-Fulcher dielectric relaxation, the hallmark of relaxor ferroelectrics. The model system of a uniaxial ferroelectric with point...

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