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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.
121

Mesures de la luminosité absolue à l'expérience LHCb / Absolute luminosity measurements at LHCb

Hopchev, Plamen 25 November 2011 (has links)
Les mesures de la luminosité intégrée pour les expériences auprés de collisionneur ont un intérêt majeur. Ces mesures participent à la détermination des sections efficaces de production des processus étudiés, elles quantifient également les performances de l'accélérateur et des expériences. Deux méthodes ont été utilisées par l'expérience LHCb pour déterminer la mesure de la luminosité absolue enregistrée durant la campagne 2010 de prise de données des collisions proton-proton à une énergie de 7 TeV dans le centre de masse: outre la méthode classique applelée "Van der Meer scan" une nouvelle technique est développée permettant une détermination directe des paramètres de chaque faisceau en localisant les interactions faisceau-faisceau et les interactions faisceau-gaz résiduel. Cette méthode n'est possible que grace à la résolution du détecteur de vertex de LHCb et sa proximité avec la zone des faisceaux de protons et les paramètres tels la position, les angles et les largeurs des faisceaux peuvent être mesurés. Les deux methodes sont décrites et leurs résultats discutés. De plus les techniques utilisées pour étendre les mesures de luminosité absolue à l'ensemble de la prise de données 2010 sont décrites. / Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the 2010 LHC run at a centre-of-mass energy of 7 TeV. In addition to the classic ``van der Meer'' scan method a novel technique has been developed which allows a direct imaging of the individual beams to be made by measuring both proton-gas and proton-proton interactions. The beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. We describe both methods and compare the two results. In addition, we present the techniques used to transport the absolute luminosity measurement to the full data-taking period.
122

New tests and test methodologies for scan cell internal faults

Yang, Fan 01 December 2009 (has links)
Semiconductor industry goals for the quality of shipped products continue to get higher to satisfy customer requirements. Higher quality of shipped electronic devices can only be obtained by thorough tests of the manufactured components. Scan chains are universally used in large industrial designs in order to cost effectively test manufactured electronic devices. They contain nearly half of the logic transistors in large industrial designs. Yet, faults in the scan cells are not directly targeted by the existing tests. The main objective of this thesis is to investigate the detectability of the faults internal to scan cells. In this thesis, we analyze the detection of line stuck-at, transistor stuck-on, resistive opens and bridging faults in scan cells. Both synchronous and asynchronous scan cells are considered. We define the notion of half-speed flush test and demonstrate that such new tests increase coverage of internal faults in scan cells. A new set of flush tests is proposed and such tests are applied at higher temperatures to detect scan cell internal opens with a wider range of resistances. We also propose new scan based tests to further increase the coverage of those opens. The proposed tests are shown to achieve the maximum possible coverage of opens in transistors internal to scan cells. For an asynchronous scan cell considered, two new flush tests are added to cover the faults that are not detected by the tests for synchronous scan cells. An analysis of detection of a set of scan cell internal bridging faults is described. Both zero-resistance and nonzero-resistance bridging fault models are considered. We show that the detection of some zero-resistance non-feedback bridging faults requires two-pattern tests. We classify the undetectable faults based on the reasons for their undetectability. We also propose an enhanced logic BIST architecture that accomplishes the new flush tests we propose to detect scan cell internal opens. The effectiveness of these new methods to detect scan cell internal faults is demonstrated by experimental results using some standard scan cells from a large industrial design.
123

Two-photon absorption studies in organic compounds and polymers / Estudos de absorção de dois fótons em moléculas orgânicas e polímeros

Dipold, Jessica 17 April 2019 (has links)
High two-photon absorption (2PA) cross-section materials have been frequently studied during the latest years due to the wide variety of technological applications, such as two-photon absorption microscopy (2PM) and microfabrication. The characterization of new materials with high nonlinearities is, therefore, indispensable to develop new applications and improve previously existing ones. Here, three different groups of novel organic compounds had their nonlinearities characterized through two-photon absorption measurements: fluorenone based compounds, which are usually used in two-photon absorption microscopy; BF2-naphthyridine (BODIPY) complexes, which have a wide range of applications, from solar cells to photodynamic therapy; and binaphthalene-based polymers, with structures built to generate large nonlinearities through inherent chirality. All compounds had their two-photon absorption spectra studied through absorptive Z-Scan, with density functional theory (DFT) calculations made to interpret the results for the first two groups of compounds, and polarization controlled measurements made for the polymers. The highest 2PA cross-section presented by the fluorenone-based compounds was of 224 GM at 710 nm, large and within the wavelength range for 2PM applications; for the BODIPYs, the largest observed cross-section was of 268 GM at 990 nm, of the same order of magnitude of more complex compounds; and 680 GM at 1100 nm for the polymer, showing a high cross-section as expected from its structure. The desired applications for the studied molecules were shown valid, and their characterization gave a better understanding of how to increase their nonlinearities depending on the compound manufacture. / Materiais com grande seção de choque de absorção de dois fótons (2PA) tem sido estudados com frequência nos últimos anos graças a ampla variedade de aplicações tecnológicas, tais como microscopia por absorção de dois fótons (2PM) e microfabricação. A caracterização de materiais com altas não-linearidades é, portanto, indispensável para o desenvolvimento de novas aplicações e para o aprimoramento das técnicas já existentes. Aqui, três diferentes grupos de novos compostos orgânicos tiveram suas não-linearidades caracterizadas através de medidas de 2PA: compostos baseados em fluorenona, geralmente utilizados em 2PM; compostos baseados em BF2-naftiridina (BODIPY), que possuem grande variedade de aplicações, desde células solares até terapia fotodinâmica; e polímeros baseados em binaftaleno, com estruturas sintetizadas para gerar altas não-linearidades através de sua quiralidade inerente. Para caracterizar o espectro de 2PA de todos os compostos a técnica de Z-Scan absortiva foi utilizada, com cálculos de funcional densidade (DFT) realizados para corroborar os resultados obtidos para os dois primeiros grupos de compostos, e medidas com controle de polarização foram realizados para o estudo dos polímeros. A maior seção de choque obtida para as fluorenonas foi de 224 GM em 710 nm, alta e dentro do comprimento de onda necessário para as aplicações de 2PM; para os BODIPYs, a maior seção de choque observada foi de 268 GM em 990 nm, da mesma ordem de magnitude que compostos mais complexos que os estudados; e 680 GM em 1100 nm para o polímero, mostrando um valor alto como esperado por sua estrutura. Com isso, demonstramos que as moléculas estudadas possuem as aplicações desejadas, e sua caracterização permitiu uma melhor compreensão de como aumentar suas não-linearidades dependendo da engenharia dos compostos.
124

"Estudo das contribuições térmica e eletrônica na variação do índice de refração de materiais dopados com íons emissores" / Study of thermal and electronic contribution to the refractive index variation of materials doped with ions emiters

Djalmir Nestor Messias 16 February 2006 (has links)
Neste trabalho estudamos as propriedades térmicas e óticas de íons emissores usando as técnicas de lente térmica e z-scan, resolvidas no tempo. Foram obtidos o espectro fototérmico de lente térmica de amostras dopadas com Yb3+ e diversos outros parâmetros fototérmicos. Foi também realizado um estudo dos efeitos da saturação da não linearidade ótica sobre a determinação das propriedades eletrônicas em sólidos dopados com Cr3+, utilizando a técnica de z-scan. A seguir a mesma técnica foi aplicada na obtenção do parâmetro de upconversion em materiais dopados com Nd3+ e Cr3+ (com excitação ressonante e não ressonante ao nível laser emissor). Empregando a integral de difração foram investigados os efeitos do processo de upconversion Auger sobre a refração não linear. Os resultados experimentais e numéricos mostraram uma excelente concordância. Também foi investigado o comportamento temporal da população do nível emissor na fase de excitação, demonstrando assim uma forma alternativa de obter o parâmetro de upconversion. Finalmente, usando a técnica de z-scan obtivemos a forma de linha da não linearidade ótica de uma amostra dopada com Yb3+ onde demonstramos que a contribuição mais importante para a não linearidade do íon advém de transições no UV, mesmo estando o íon sob excitação ressonante ao nível emissor. / In this work we have studied the thermal and optical properties of emitters ions by using the thermal lens and z-scan time resolved techniques. It was obtained the thermal lens photothermal spectra of Yb3+ doped samples, and several other photothermal parameters. Also, it was done a study on the optical nonlinearity saturation effects over the determination of the optical properties in Cr3+ doped solids, using the z-scan technique. In the sequence the same technique was used in order to obtain the upconversion parameter in Nd3+ and Cr3+ doped materials (with excitation resonant and non resonant to the emitter level). Employing the diffraction integral, the effects of Auger upconversion process on the nonlinear refraction were investigated. The experimental and numerical results agree very well. It was also investigated the temporal behavior of the emitter level population during the excitation process, showing an alternative way to obtain the upconvertion parameter. Finally, by using the z-scan technique we have obtained the optical nonlinear lineshape of a Yb3+ doped sample, and demonstrated that the major contribution to the optical non linearity arises from the UV transitions, even when the emitter level of the ion is under resonant excitation.
125

Espectroscopia de lente térmica e de lente de população em sólidos dopados com íons terras-raras / Spectroscopy of thermal and population lens in rare-earth doped solids

Sandro Marcio Lima 25 February 2003 (has links)
As técnicas de lente térmica (LT) e \"Z-scan\" foram usadas para estudar as propriedades termo-óticas (difusividade térmica, condutividade térmica, taxa de variação do caminho ótico em função da temperatura e eficiência quântica de fluorescência) e não-lineares (partes real e imaginária do índice de refração não-linear, diferença de polarizabilidade e da seção de choque de absorção entre os estados excitado e fundamental, respectivamente) de sólidos dopados com Neodímio e Cromo. Uma nova extensão da técnica de LT foi proposta para determinar a eficiência quântica de fluorescência sem necessitar de amostra referência, como é feito na maioria dos métodos fototérmicos. Além disso, ambas técnicas foram usadas como espectroscopia, ou seja, a LT foi usada para estudar a forma de linha do calor gerado no material quando a excitação é feita próximo da banda de absorção do material, possibilitando assim a determinação da eficiência de transferência entre a matriz e o íon dopante, e a técnica \"Z-scan\" foi adaptada para medir a forma de linha do índice de refração não-linear próximo das linhas de emissão laser nos cristais dopados com Cromo. / The Thermal Lens (TL) and Z-scan technique were used to study the thermo-optical (thermal diffusivity, thermal conductivity, temperature coefficient of the optical path length change and fluorescence quantum efficiency) and nonlinear optical (parts real and imaginary of the refractive index, polarizability difference and absorption cross section between the excited and ground states, respectively) properties of Neodymium and Chromium doped solids. A new extension of the TL technique was proposed to determine the fluorescence quantum efficiency without measuring a reference sample, as done by any photothermal method Moreover, both techniques were used as an spectroscopy one, i. e., the TL was used to study the line shape of the heat created in material when the excitation is done near at the host absorption band, allowing the determination of the energy transfer efficiency between the host and the dopant ion, and the 2-scan technique was adapted to measure the line shape of the nonlinear refractive index near the laser lines in Chromium doped crystals.
126

Papel do ômega-3 nas características físico-químicas da HDL e LDL e possível associação com medidas Z-scan em indivíduos adultos / Role of omega-3 on HDL and LDL physicochemical characteristics and possible association with Z-scan measurements in adults

Maria Camila Pruper de Freitas 07 August 2015 (has links)
Introdução: O aumento na prevalência das doenças cardiovasculares alerta para a necessidade de estratégias eficazes e de baixo custo como medidas preventivas na redução dos fatores de risco, morbidades e óbitos decorrentes de eventos coronarianos. As modificações no estilo de vida são as primeiras alternativas a serem adotadas. Nesse contexto, a dieta ocupa lugar de destaque e os benefícios dos ácidos graxos poli-insaturados ômega-3 na saúde cardiovascular são amplamente reconhecidos. As doenças cardiovasculares são influenciadas por diversos fatores de risco e o desequilíbrio na concentração plasmática das lipoproteínas é um fator de risco independente no desenvolvimento da doença cardiovascular aterosclerótica. Entretanto, há evidências de que as subfrações lipoproteicas podem influenciar o risco cardiovascular de maneira diferenciada, dependendo das características físico-químicas e funcionalidade de cada partícula. O desenvolvimento de novas técnicas, capazes de identificar esses parâmetros, tem sido foco de grande interesse científico. Objetivo: Avaliar o papel do ômega-3 sobre as características físico-químicas da LDL e HDL e possível associação entre medidas Z-scan e marcadores cardiometabólicos em indivíduos adultos. Metodologia: A partir de uma subamostra do estudo CARDIONUTRI (estudo clínico, randomizado, controlado e duplo cego com seguimento de 8 semanas) foram selecionados 36 indivíduos do Grupo Ômega-3 (3,0g/dia de óleo de peixe - 1,11g de EPA + 0,69g de DHA) e 27 do Grupo Placebo (3,0g/dia de óleo mineral). Foram monitorados o perfil clínico, antecedentes familiares, consumo alimentar, atividade física e antropometria. Amostras de sangue foram coletadas após 12 horas de jejum para avaliação das concentrações plasmáticas de CT, TAG, HDL-C, LDL-C, APOAI, APOB, PON1 e glicose. O tamanho da HDL e LDL foi analisado pelo método padronizado Lipoprint®. O conteúdo de LDL(-) foi determinado por ELISA. As medidas Z-scan foram determinadas por meio da difusividade térmica e absorção linear da LDL (1,0 mg/dL de proteína), isolada por ultracentrifugação. Todos as variáveis do estudo foram avaliadas no momento basal e após 8 semanas de intervenção. A adesão à intervenção foi monitorada pela contagem de cápsulas e percentual dos ácidos graxos plasmáticos. Para avaliar a associação das medidas Z-Scan aos marcadores cardiometabólicos, os dados obtidos no momento basal foram submetidos à Análise de Componentes Principais. Resultados: A idade média dos participantes do estudo foi de 51,5 (10,5) anos. A suplementação com ômega-3 promoveu redução significativa de CT, TAG, não-HDL, HDLPEQUENA e LDL(-), além de aumento significativo de HDL-C e HDLGRANDE. O ômega-3 foi mais eficaz na redução dos TAG (29,2 por cento ) quando comparado ao placebo (2,9 por cento ). O Grupo Ômega-3 apresentou aumento de HDLGRANDE (16,9 por cento ) e redução de HDLPEQUENA (-16,3 por cento ) ao final da intervenção, com diferença significativa quando comparado ao Grupo Placebo que apresentou redução de HDLGRANDE (-4,8 por cento ) e aumento de HDLPEQUENA (17,7 por cento ). Não foram observadas diferenças nas medidas Z-scan após a intervenção, porém as medidas se associaram positivamente a Componentes Principais com padrões cardioprotetores da amostra e negativamente a padrões aterogênicos. Conclusão: O ômega-3 demonstrou efeito positivo no perfil lipídico e propriedades aterogênicas das subfrações lipoproteicas. A suplementação com ômega-3 não modificou as medidas Z-scan, no entanto, a técnica demonstrou ser uma ferramenta capaz de se associar a padrões aterogênicos e antiaterogênicos monitorados no presente estudo / Introduction: The increased of cardiovascular disease prevalence draws attention to the need to adopt effective and inexpensive strategies as preventive measures to reduce risk factors, morbidity and deaths from coronary events. Lifestyle modification is indicated as first alternative to be adopted. In this context the diet stands out and omega-3 polyunsaturated fatty acids benefits on cardiovascular health are largely recognized. Cardiovascular diseases are influenced by several risk factors and the plasma imbalance lipoprotein is considered a crucial independent risk factor. However, there is evidence of the influence of lipoprotein subfractions in cardiovascular risk, based on the physicochemical characteristics of these particles. The development of new techniques able to identify those parameters has been the focus of great scientific interest. Objective: To evaluate the role of omega-3 on HDL and LDL physicochemical characteristics and possible association between Z-scan measurements and cardiometabolic markers in adults. Methods: From a subsample of the study CARDIONUTRI (clinical, randomized, controlled, double blind study with 8-week follow-up) were selected 36 individuals from the Omega-3 Group (3.0g/day of fish oil - 1,11g EPA + 0.69g DHA) and 27 individuals from the Placebo Group (3.0g/day of mineral oil). The clinical profile, family history, dietary intake, physical activity and anthropometry were monitored. Blood samples were collected after 12 hours of fasting to evaluate plasma concentrations of TC, TAG, HDL-C, LDL-C, APOAI, APOB, PON1 and glucose. The HDL and LDL size was analyzed by the standard method Lipoprint®. The levels of LDL (-) was determined by ELISA. The Z-scan measurements were determined by thermal diffusivity and linear absorption of LDL (1.0 mg / dL protein) isolated by ultracentrifugation. All study variables were evaluated at baseline and after 8 weeks of intervention. The intervention accession was monitored by capsule count and percentage of plasma fatty acids. To evaluate the association of the Z-Scan measurements to cardiometabolic markers, the data collected at baseline were subjected to Principal Component Analysis. Results: The average age of individuals were 51.5 (10.5) years. The omega-3 supplementation promoted a significant decreased of TC, TAG, non-HDL, small HDL and LDL(-), and significantly increased HDL-C and large HDL. The omega-3 was more effective in reducing the TAG (29.2 per cent ) when compared to placebo (2.9 per cent ). The Omega-3 Group increased large HDL (16.9 per cent ) and decreased small HDL (-16.3 per cent ) after the intervention, with significant difference when compared to the Placebo Group that decreased large HDL (-4.8 per cent ) and increased small HDL (17.7 per cent ). There were no differences in Z-scan measurements with the interventions, but were observed positively associated the Z-scan measurements with the anti-atherogenic sample patterns and negatively associated with atherogenic sample patterns when the sample was standardized from the Principal Components Analysis. Conclusion: The omega-3 demonstrated positive effect on the lipid profile and atherogenic lipoprotein subfractions. Supplementation with omega-3 did not modify the Z-scan measurements, however, the technique proved to be a tool that can be associated with atherogenic and anti-atherogenic sample patterns monitored in this study.
127

Modélisation de la réponse au traitement en oncologie : exemples en radiothérapie et en thérapies ciblées / Treatment response modeling in oncology : examples in radiotherapy and targeted therapies

Berment, Perrine 06 July 2016 (has links)
Cette thèse présente des travaux de modélisation mathématiquede la réponse au traitement en oncologie appliquée à trois pathologies différentes.La première partie traite du cas des GIST et de la réponse à la thérapie ciblée.Deux modèles sont décrits afin d’étudier différents critères de suivie del’évolution tumorale. La deuxième partie porte sur les tumeurs colorectales etla réponse à la radiothérapie. Un premier modèle d’équations aux dérivées partielles,couplé à un modèle décrivant l’examen du PET-scan, est mis en place,puis il est simplifié afin de rendre la phase de calibration plus rapide. Cetteméthode est testée sur deux cas cliniques.La dernière partie traite des tumeurs ORL sous radiothérapie. Une méthodede personnalisation du modèle, similaire à celle de la partie précédente, est miseen place et est testée sur six cas cliniques. / We first present two mathematical models to simulate the evolution and theresponse to treatments of GIST.Then, we study colorectal tumors and radiotherapy response. We present apartial differential equations model to simulate the tumor evolution, the responseto radiotherapy and the PET-scan. We introduce a simplification of thefirst model to develope a calibration technic based on medical images of thetumor. Two applications on clinical cases are presented.To finish, a similar method is adapted to ORL tumors and response to radiotherapyand tested on six clinical cases.
128

Bases génétiques de l’adaptation du moustique tigre Aedes albopictus à de nouveaux environnements : une approche sans à priori reposant sur les éléments transposables / Adaption genetics of the Asian tiger mosquito Aedes albopictus toward new environments : a without a priori approach based on transposable elements

Goubert, Clément 04 December 2015 (has links)
Le moustigre tigre Aedes albopictus, un des vecteurs de la Dengue et du Chikungunya, est une espèce invasive qui a colonisé le monde entier en 30 ans à partir de son berceau asiatique. Les éventuelles bases génétiques de ce succès sont inconnues. Afin d’étudier l’ampleur de la différenciation génétique entre populations asiatiques et européennes et la part prise par la sélection naturelle dans cette différenciation, nous avons développé de nouveaux marqueurs génétiques reposant sur le polymorphisme d’insertion des éléments transposables. Pour cela, nous avons dans un premier temps conçu un outil bioinformatique –dnaPipeTE— nous permettant de dresser le portrait de la fraction répétée du génome d’Ae. albopictus à partir d’une faible proportion des lectures brutes issues d’un projet de séquençage en cours. Le polymorphisme d’insertion de cinq des familles d’ET décrites a ensuite été étudié par la technique de transposon display couplée à du séquençage Illumina, chez 140 individus issus de trois populations vietnamiennes et cinq populations européennes. L’immense majorité des 128 000 marqueurs analysés montre une différenciation génétique très faible entre Europe et Asie. Nous avons néanmoins pu mettre en évidence un centaine d’insertions ayant des fréquences extrêmement différentes entre ces continents. La majorité d’entre elles ségrège à forte fréquence en Europe, suggérant une adaptation du moustique à son environnement tempéré / The Asian tiger mosquito, one of the main vectors of Dengue and Chikungunya, is an invasive species that colonized the world during the last 30 years from its cradle in Asia. Whether this success has an underlying genetic basis remains to be investigated. In order to study the extent of the genetic differentiation between Asian and European populations and the contribution of natural selection to this differentiation, we developed new genetic markers based on transposable elements insertion polymorphism. We first conceived a bioinformatic pipeline –dnaPipeTE— that allowed to grasp a comprehensive picture of the repetitive fraction of the Tiger’s genome through the analysis of a low proportion of raw reads from a ongoing sequencing project. The insertion polymorphism of five transposable element families was then studied by Illumina based transposon display, in 140 individuals from three Vietnamese populations and five European populations. The vast majority of the 128,000 markers showed a very low genetic differentiation between Europe and Asia. However 92 of them displayed extreme frequency differences between the continents. The majority of them segregate at high frequencies in Europe, a pattern suggestive of adaptive evolution towards temperate environments
129

Génomique de l'adaptation de Globodera pallida aux résistances de la pomme de terre et conséquences sur les traits d'histoire de vie du nématode / Genomics of Globodera pallida adaptation to potato resistances and consequences on the nematode life-history traits

Eoche-Bosy, Delphine 23 November 2016 (has links)
L’étude des modifications phénotypiques et génomiques associées à l’adaptation des pathogènes aux résistances est une étape fondamentale pour mieux comprendre et anticiper le phénomène de contournement des résistances. Le nématode à kyste Globodera pallida est un important pathogène de la pomme de terre, vis-à-vis duquel un QTL majeur de résistance, GpaVvrn, a été identifié chez Solanum vernei. Cependant, la capacité des populations de G. pallida à s’adapter à cette résistance en quelques générations seulement a été mise en évidence par évolution expérimentale. Dans ce contexte, ce travail de thèse avait pour objectifs (1) d’étudier les traits d’histoire de vie du nématode impactés par l’adaptation, afin de tester l’existence éventuelle d’un coût de virulence, et (2) d’identifier les régions génomiques impliquées dans l’adaptation, par une approche originale combinant évolution expérimentale et scans génomiques sur des lignées virulentes et avirulentes. Contre toute attente, nous avons montré que l’adaptation à la résistance issue de S. vernei entraînait une augmentation de la fitness des individus virulents sur hôte sensible. Nous avons également pu identifier des régions génomiques candidates à l’adaptation à la résistance de la plante hôte, contenant des gènes codant pour des effecteurs, et notamment des SPRYSECs, connus chez les nématodes à kyste pour être impliqués dans la suppression des défenses des plantes mais aussi dans la virulence du nématode. À terme, ces résultats s’avéreront utiles pour la conception de stratégies durables de déploiement de variétés de pommes de terre résistantes. / Studying phenotypic and genomic modifications associated with pathogen adaptation to resistance is a crucial step to better understand and anticipate resistance breakdown. The cyst nematode Globodera pallida is an important pest of potato crops, for which a major resistance QTL, GpaVvrn, has been identified in Solanum vernei. However, the capability of G. pallida populations to adapt to this resistance in only few generations has been highlighted through experimental evolution. In this context, the purposes of this work were (1) to study the nematode life-history traits impacted by adaptation, in order to test for potential existence of a virulence cost, and (2) to identify genomic regions involved in adaptation, through an original approach combining experimental evolution and genome scans on virulent and avirulent lineages. Unexpectedly, we highlighted that adaptation to resistance from S. vernei leads to an increase of virulent individual’s fitness on susceptible host. We were also able to pinpoint candidate genomic regions to adaptation to host plant resistance, containing genes encoding effectors, and especially SPRYSECs, known in cyst nematodes to be involved in suppression of host defense but also in nematode virulence. These results will ultimately be useful in order to conceive sustainable strategies of use of potato resistant cultivars
130

Zkoumání souvislostí mezi pokrytím poruch a testovatelností elektronických systémů / Investigating of Relations between Fault-Coverage and Testability of Electronic Systems

Rumplík, Michal January 2010 (has links)
This work deals with testability analysis of digital circuits and fault coverage. It contains a desription of digital systems, their diagnosis, a description of tools for generating and applying tests and sets of benchmark circuits. It describes the testing of circuits and experimentation in tool TASTE for testability analysis and commercial tool for generating and applying tests. The experiments are focused on increase the testability of circuits.

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