Introdução: No mundo especula-se que 15 a 20 milhões tenham infecção crônica pelo HDV. No Brasil, a área endêmica de hepatite Delta corresponde aos estados da Amazônia Ocidental, incluindo Rondônia. Hepatite Delta é a mais grave e com mais rápida evolução para cirrose dentre as hepatites virais. Poucos estudos avaliaram os aspectos epidemiológicos, clínicos e laboratoriais de uma coorte de pacientes em nosso país e no mundo. Objetivos: Em uma coorte de pacientes acompanhados em um serviço de referência: 1. Avaliar as características demográficas, epidemiológicas e clínicas; 2. Avaliar a frequência de doença hepática avançada; 3. Avaliar as características da população atendida com idade <=18 anos; 4. Avaliar a acurácia de escores não invasivos (razão AST/ALT, APRI e FIB-4) na determinação dos diferentes graus de fibrose. Métodos: Trata-se de um estudo transversal, descritivo, de uma coorte de pacientes retrospectivamente identificadas no ambulatório especializado em hepatites virais, pertencente ao Centro de Pesquisa em Medicina Tropical do Estado de Rondônia (CEPEM), situado na cidade de Porto Velho, com diagnóstico de infecção pelo HDV. Foram incluídos todos os pacientes com diagnóstico dessa infecção por sorologia (ELISA) ou por biologia molecular (HDV-RNA reagente), matriculados e atendidos neste serviço entre novembro de 1996 a março de 2015. Resultados: Dentre 4.101 pacientes diagnosticado com HBV, 224 (5,5%) apresentavam coinfecção com o HDV, e 205 foram incluídos nas análises. Dentre eles, 132 (64,4%) eram do sexo masculino, com idade média de 35,1 anos. O contato familiar foi o fator de exposição para infecção pelo VHB/VHD mais frequente. A determinação do genótipo do HDV foi obtida em 78 pacientes, destes 74 (94,9%) eram genótipo III e 4 (5,1%) genótipo I. Noventa e dois (44,9%) pacientes apresentavam evidência de doença hepática avançada. Dentre os pacientes incluídos 22 (10,7%) tinham idade <= 18 anos, sendo que 6 (27,3%) apresentavam sinais e sintomas de doença hepática avançada ou fulminante à primeira consulta. Métodos não invasivos foram calculados e comparados à biópsia hepática em 50 pacientes. A razão AST/ALT não teve valor significativo para avaliar fibrose em nenhum dos estágios. APRI e FIB-4 tiveram melhor desempenho para avaliar fibrose significativa (>=F2), com acurácia de 86 e 80, respectivamente. Conclusões: 1. O HDV representa importante agravo de saúde pública em Rondônia com frequência expressiva entre pessoas do sexo masculino e população indígena; 2. A presença da infecção pelo HDV esteve associada a expressivo número de complicações hepáticas e foi frequente causa de óbito na população analisada, particularmente entre adultos jovens; 3. Entre pacientes com idade <= 18 anos a hepatite delta esteve associada a significante morbidade e mortalidade e a falta de adesão dessa população pareceu contribuir para esse tipo de desfecho; 4. A utilização dos métodos não invasivos (APRI e FIB-4) foi capaz de identificar pacientes com fibrose significativa entre indivíduos infectados com HDV na Amazônia brasileira, podendo, apesar de todas as limitações destes métodos servir como alternativa para avaliação de fibrose hepática significativa, na ausência de outros métodos mais efetivos / Introduction: In the world, it is speculated that 15 to 20 million people have chronic HDV infection. In Brazil, the endemic area of hepatitis Delta corresponds to the states of the Western Amazon, including Rondônia. Hepatitis Delta is the most serious and most rapidly evolving cirrhosis among viral hepatitis. Few studies have evaluated the epidemiological, clinical, and laboratory aspects of a cohort of patients in our country and around the world. Objectives: In a cohort of patients followed at a referral service: 1. Evaluate demographic, epidemiological and clinical characteristics; 2. Assess the frequency of advanced liver disease; 3. Evaluate the characteristics of the population served with age <=18 years; 4. To evaluate the accuracy of non-invasive scores (AST/ALT ratio, APRI and FIB-4) in determining the different degrees of fibrosis. Methods: This is a cross-sectional, descriptive study of a cohort of patients retrospectively identified in the ambulatory specialized in viral hepatitis, belonging to the Research Center of Tropical Medicine of Rondônia State (CEPEM), located in the city of Porto Velho. All patients diagnosed with this serological method (ELISA) or molecular biology (HDV-RNA), enrolled in this service between November 1996 and March 2015, were included. Results: Out of 4,101 patients diagnosed with infection by HBV, 224 (5.5%) had coinfection with the hepatitis delta virus, and 205 were included in the analyzes. Among them, 132 (64.4%) were males, with a mean age at the time of enrollment of 35.1 years. Family contact was the most frequent exposure factor for HBV/HDV infection. It was identified seventy-eight patients (94.9%) of genotype III and four (5.1%) of genotype I. Ninety-two (44.9%) patients had evidence of advanced liver disease. Among the patients included, 22 (10.7%) were aged <= 18 years, and 6 (27.3%) had signs and symptoms of advanced or fulminant liver disease at the first visit. Noninvasive methods were calculated and compared to liver biopsy in 50 patients. The AST/ALT ratio had no significant value for evaluating fibrosis in any of the stages. APRI and FIB-4 had better performance to evaluate significant fibrosis (>=F2), with the accuracy of 86 and 80 respectively. Conclusions: 1. The hepatitis delta virus represents an important public health problem in the State of Rondônia, affecting both adults and children, with significant frequency among males and the indigenous population; 2. The presence of HDV infection was associated with a significant number of hepatic complications and was a frequent cause of death in the analyzed population, particularly among young adults; 3. Among patients aged <= 18 years, delta hepatitis was associated with significant morbidity and mortality and the lack of adherence of this population to follow-up seemed to contribute to this type of outcome; 4. The use of the non-invasive APRI and FIB-4 methods were able to identify patients with significant fibrosis among individuals infected with HDV in the Brazilian Amazon, although all limitations of these methods may serve as an alternative for the evaluation of significant hepatic fibrosis in the absence of other more effective methods

De nos jours, les capteurs capacitifs sont largement utilisés dans la mesure de grandeurs physiques telles que le déplacement, l’humidité, la pression, etc. Cette large diffusion est principalement due au développement des technologies MEMS qui ont permis de réduire leur coût, leur taille et leur consommation. Pour mesurer ces variations de capacité, des interfaces de conditionnement électronique ont été développées afin d’obtenir un signal électrique exploitable tel qu’une tension, un courant, un temps, une fréquence ou directement une sortie numérique. C’est dans ce cadre que se positionne l’objectif de cette thèse ; étudier la faisabilité d’une mesure capacitive à sortie numérique à partir d’un pont actif, une architecture développée et brevetée par l’équipe Conception et Test de Microsystèmes du LIRMM pour le conditionnement de capteurs résistifs basse consommation. La conversion numérique utilisée est une modulation Sigma-Delta 1 bit du 1er ordre, relativement facile à implémenter, et donc bien adaptée à l’intégration, à la faible consommation et à la réalisation d’interfaces génériques. Pour le retour 1 bit, deux structures de contre réaction ont été proposées : une contre-réaction résistive et une capacitive. Les résultats théoriques sont comparés à des résultats de simulations et à des mesures obtenues à partir des prototypes fabriqués en technologie CMOS 0,35μm d’Austria MicroSystem (AMS). / Nowadays, capacitive sensors are widely used in the measurement of physical quantities such as displacement, humidity, pressure, etc. This wide dissemination is mainly due to the development of MEMS technologies that have reduced their cost, size and consumption. To measure these capacitance changes, sensor electronic interfaces have been developed to obtain an exploitable electrical signal such as voltage, current, time, frequency or directly a digital output. It is in this framework that the aim of this thesis is positioned ; to study the feasibility of a capacitive measurement with digital output from an active bridge, an architecture developed and patented by the Design and Test Microsystems team of LIRMM for conditioning low power resistive sensors. The digital conversion used is a one-bit first-order Sigma-Delta modulation that is relatively easy to implement, and is well adapted to integration, low power consumption and realization of generic sensor interfaces. Two feedback architectures have been proposed: a resistive feedback and a capacitive. The theoretical results are compared with the results of simulations and measurements obtained from prototypes fabricated using a 0.35μm CMOS technology from Austria MicroSystem (AMS).

Neste trabalho, aplicamos um modelo de regressão binária com erros de medição na variável explicativa para analisar sistemas de medição do tipo atributo. Para isto, utilizamos o modelo logístico com erros na variável, para o qual obtemos as estimativas de máxima verossimilhança via o algoritmo EM e a matriz de informação de Fisher observada. Além disso, fizemos um estudo de simulação para compararmos o método analítico e os modelos logístico sem erros na variável (ingênuo) e logístico com erros na variável. Finalmente, aplicamos nossa metodologia para avaliarmos um sistema de medição passa/não passa da maior montadora de motores Diesel (MWM International). / In this work, we apply a study of binary regression model with errors-in-variable to analyze attributive measurement systems. For this, we use the logistic model with errors-in-variable to obtain parameter estimates of maximum likelihood through EM algorithm and the observed Fisher information matrix. In addition we do a simulation study to compare analytic method and the logistic model with and without measurement errors-in-variable. Finally, we apply our methodology to evaluate a attributive measurement system for the largest Diesel motor company of the world (MWM International).

Les sécheresses des années 1970 accentuées dans les années 1980 et les aménagements hydroagricoles ont eu pour conséquence une certaine dégradation des ressources naturelles du delta intérieur du fleuve Niger (DIN). Cette dégradation des ressources naturelles associées à la pression croissante de la population sur le milieu a conduit à une gestion conflictuelle de ces ressources. De plus, le système d’exploitation actuel des ressources et le fonctionnement hydrologique font du DIN un écosystème complexe à gérer. Dans ces travaux, nous adoptons une approche intégrée et pluridisciplinaire pour aborder la problématique de gestion des ressources du DIN. L’approche mobilise l’hydrologie, la sociologie, l’agronomie et l’économie. L’analyse des données hydrologiques a permis de mettre en évidence une différence significative entre les dates de passage des maximums des fleuves Niger et Bani qui alimentent le DIN. Cette différence impacte les calendriers des principaux systèmes de production contribuant ainsi à exacerber les conflits. Les stratégies de gestion élaborées avec les parties prenantes, allient des pratiques de sécurisation et de maîtrise de l’eau, d’intensification, de régénération des ressources, de renforcement des capacités et des incitations économiques. Par ailleurs, dans un contexte de variabilité climatique accrue, nous avons analysé les perceptions d’un échantillon de pêcheurs, d’éleveurs et de cultivateurs sur la prévision du climat et sur l’intérêt des prévisions climatiques et des crues. Il ressort que les besoins en information climatique des usagers d’une plaine inondable comme le DIN se rapportent surtout aux dates de début de saison, de passage des maximums de crue, de la date d’arrivée des crues et des hauteurs maximales de crue. L’intérêt économique simulé de l’information climatique pour un système agraire de riziculture inondée présente un gain moyen de 10%. Par contre le coût des éventuelles erreurs de prévision serait particulièrement élevé pour les producteurs avec un déficit moyen sur le revenu de 24%. / The droughts of the 1970s intensified in the 1980s and the development of irrigation schemes upstream of the Inner Niger Delta in Mali (IND) have resulted in the degradation of natural resources. This degradation of natural resources associated with the increasing population pressure on the environment has led to a more conflictive management of these resources. In addition, the current operating system of resources and the hydrological functioning of the IND make the management of the ecosystem more complex.In this work, we adopt an integrated and multidisciplinary approach to address the IND resource management issues. The approach mobilizes hydrology, sociology, agronomy and economy.The analysis of hydrological data has highlighted a significant difference between the maximum passing dates of the two rivers that supply the IND. This difference impacts the schedules of the main production systems thus contributing to exacerbate conflict. The management strategies developed with stakeholders combine the practices of security and water control, intensification, resource regeneration, capacity building and economic incentives. Moreover, in a context of increased climate variability, we analyzed the perceptions of a sample of fishermen, herders and farmers on climate prediction and their interest of climate and flood forecasts.. It appears that the need for climate information of floodplain users as IND relate mainly to the onset date of rainy season, flood maximum passaging date, the arrival of floods and flood peak heights.The simulated economic value of climate information for an agrarian system of flooded rice obtains an average gain of 10%. As against the cost of possible prediction errors is particularly high for producers with an average deficit on income of 24%.

Poon Fung Ting. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 152-166). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.ii / ABSTRACT --- p.iii / TABLE OF CONTENTS --- p.vi / LIST OF TABLES --- p.ix / LIST OF FIGURES --- p.x / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Research Questions --- p.1 / Chapter 1.2 --- Research Objectives --- p.3 / Chapter 1.3 --- Definitions --- p.4 / Chapter 1.4 --- Research Design --- p.9 / Chapter 1.5 --- Outline of the Thesis --- p.11 / Chapter CHAPTER 2 --- BACKGROUND OF THE STUDY AND THE LITERATURE REVIEW --- p.13 / Chapter 2.1 --- Introduction --- p.13 / Chapter 2.2 --- Background of the Study --- p.15 / Chapter 2.3 --- Literature Review --- p.28 / Chapter 2.4 --- Summary --- p.38 / Chapter CHAPTER 3 --- SPATIAL PATTERNS OF NON-HUKOU MIGRANTS IN THE PEARL RIVER DELTA --- p.41 / Chapter 3.1 --- Introduction --- p.41 / Chapter 3.2 --- Proportion of Non-hukou Migrants --- p.44 / Chapter 3.3 --- Distribution of Migrants --- p.47 / Chapter 3.4 --- Sources of Migrants --- p.50 / Chapter 3.5 --- The PRD as a Destination --- p.56 / Chapter 3.6 --- Gender Ratio of Non-hukou Migrants --- p.64 / Chapter 3.7 --- Spatial Patterns and Correlation of Migration Indicators --- p.67 / Chapter 3.8 --- Summary --- p.79 / Chapter CHAPTER 4 --- ANALYZING THE DETERMINANTS OF NON-HUKOU POPULATION IN COUNTY-LEVEL AREAS --- p.83 / Chapter 4.1 --- Introduction --- p.83 / Chapter 4.2 --- Method --- p.84 / Chapter 4.3 --- Variables --- p.86 / Chapter 4.4 --- The Results --- p.90 / Chapter 4.5 --- Summary --- p.102 / Chapter CHAPTER 5 --- IMPACTS OF NON-HUKOU MIGRANTS AND THE POLICY RESPONSES --- p.104 / Chapter 5.1 --- Introduction --- p.104 / Chapter 5.2 --- The Trend of Non-hukou Migrants in PRD --- p.106 / Chapter 5.3 --- Positive Impacts --- p.110 / Chapter 5.4 --- Negative Impacts --- p.115 / Chapter 5.5 --- Policy Responses --- p.121 / Chapter 5.6 --- Summary --- p.139 / Chapter CHAPTER 6 --- CONCLUSION --- p.142 / Chapter 6.1 --- Non-hukou Migration in PRD --- p.142 / Chapter 6.2 --- Policy Responses --- p.147 / Chapter 6.3 --- Suggestions for Further Research --- p.150 / REFERENCES --- p.152

Chez les vertébrés gnathostomes, le système immunitaire repose en grande partie sur les lymphocytes T qui se développent dans un organe conservé évolutivement : le thymus. Chez les mammifères, cet organe constitue une cible privilégiée pour les œstrogènes. La question soulevée ici est donc de savoir si c’est également le cas chez les poissons téléostéens. Dans ce but, la distribution des différents sous-types de récepteurs aux œstrogènes a d’abord été étudiée dans le contexte d’une description de l’anatomie fonctionnelle du microenvironnement thymique. Par la suite, l’expression de gènes relatifs à la fonction thymique et aux différents sous-types de lymphocyte T a été analysée dans le thymus, le rein-antérieur et la rate de bars exposés au 17ß-œstradiol. De plus, la capacité de flambée oxydative a été évaluée sur des leucocytes du rein-antérieur et de rate à la suite d’expositions in vivo et in vitro. Finalement, la variation du nombre de thymocytes a été examinée sur des bars capturés durant trois ans. La thèse fournit de nouvelles connaissances concernant l’évolution des fonctions immunomodulatrices des œstrogènes sur la différenciation des cellules T. En effet, en plus d’une organisation morpho-fonctionnelle fortement conservée, la distribution des sous-types de récepteurs aux œstrogènes ainsi que les effets œstrogéniques apparaissent conservés au cours de l’évolution. Nos résultats suggèrent que, chez le bar comme chez les mammifères, les œstrogènes (1) stimulent une voie alternative de maturation des lymphocytes T ayant des propriétés similaires aux cellules immunitaires innées, (2) augmentent la tolérance immunitaire et (3) régulent la plasticité du thymus. / Jawed vertebrates have developed an efficient adaptive immune system partly based on T lymphocytes. They develop in an evolutionarily conserved organ, the thymus. In mammals, endogenous oestrogens are well known to regulate thymus function and plasticity. The question is, therefore, whether this is also the case in lower vertebrates, such as teleosts. To achieve these aims, firstly the distribution of oestrogen receptor subtypes was investigated on the background of a detailed description of the functional anatomy of the thymic microenvironment. Secondly, thymic function- and T cell-related gene expression was analysed in the thymus, the head-kidney and the spleen of sea bass exposed to 17ß-oestradiol. Moreover, the oxidative burst capacity in the two latter organs was evaluated in vivo and in vitro in leucocytes of the head-kidney and spleen following exposure to oestrogen. Eventually, age- and size-dependent variations in thymocyte number were examined in sea bass caught at various time points over three years. The thesis provides new insights into the evolution of the immunomodulatory function of oestrogen with respect to the thymic and peripheral T cell differentiation in vertebrates. As a matter of fact, in addition to a highly conserved morpho-functional organisation, the distribution of oestrogen receptor subtypes as well as the oestrogenic effects appear to be evolutionarily conserved. Our results suggest that in sea bass, similar to mammals, oestrogen (1) stimulates a thymic alternative pathway of T cell maturation with innate-like properties, (2) enhances immune tolerance by promoting Treg differentiation, and (3) actively regulate thymic plasticity.

Submitted by Angela Maria de Oliveira (amolivei@uepg.br) on 2019-02-08T11:08:03Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Willian Ricardo.pdf: 8465496 bytes, checksum: a01921f9da37abb9909a79e5b398408c (MD5) / Made available in DSpace on 2019-02-08T11:08:03Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Willian Ricardo.pdf: 8465496 bytes, checksum: a01921f9da37abb9909a79e5b398408c (MD5) Previous issue date: 2018-08-24 / Turbinas hidráulicas usadas em usinas hidrelétricas podem apresentar desgastes por cavitação e trincas em sua operação, as quais em alguns casos reparadas por soldagem a arco elétrico, por ser um processo de menor custo em comparação à troca da turbina. O aço inoxidável martensítico A743 grau CA6NM é empregado em serviços que requerem boa resistência mecânica associada a resistência à corrosão, principalmente em equipamento para extração de petróleo nos rotores e componentes de turbinas hidráulicas. Este trabalho tem por escopo analisar a microestrutura formada após processo de soldagem TIG (Tungsten Inert Gas) de um aço ASTM A743 CA6NM, usando material de adição similar, avaliando a presença da estrutura ferrita delta, austenita retida e carbonetos. Variando as espessuras das amostras e parâmetros de soldagem como passe único de soldagem e multipasse, mantendo temperatura de pré-aquecimento e interpasse de150ºC. Estimando a influência dos parâmetros na microestrutura com a dureza dos cordões e da ZTA. Os experimentos revelaram que um único passe de solda é suficiente para a formação de ferrita delta na forma de rede ao longo do cordão de solda e nas regiões expostas a altas temperaturas na zona termicamente afetada (ZTA), assim como o perfil de durezas da seção transversal do cordão de solda apontam durezas que variam desde 344 ± 6 HV para a região fundida, passando por um pico de dureza de 379 ± 4 HV na ZTA e terminando no metal base com 290 ± 5 HV, na solda multipasse a origem das diferentes morfologias de ferrita é múltipla, havendo uma diferença da taxa de resfriamento nos cordões,sendo que entre a base e o topo da solda pode ser percebido acumulo de ferrita delta na região interpasse e no topo do ultimo cordão de solda e a variação de largura da ZTA pelos passes subsequentes, a morfologia da ferrita delta zona termicamente afetada (ZTA) na condição multipasse, assim como o perfil de durezas da seção transversal dos cordões de solda apontam durezas que variam desde 311 ± 24 HV para a região fundida, passando por um pico de dureza de 326 ± 33 HV na ZTA. / Hydraulic turbines used in hydroelectric plants may present wear by cavitation and cracks in their operation, and in some cases repaired by electric arc welding, being a process of lower cost compared to the turbine exchange. A743 grade martensitic stainless steel CA6NM is used in services that require good mechanical resistance associated with corrosion resistance, especially in oil extraction equipment, rotors and hydraulic turbine components. This work aims to analyze the microstructure formed after TIG (Tungsten Inert Gas) welding of an ASTM A743 CA6NM steel, using similar addition material, evaluating the presence of the delta ferrite, retained austenite and carbides structure. By varying the sample thicknesses and welding conditions as single pass welding and multipass, maintaining preheating temperature and interpass of 150ºC. Estimating the influence of the parameters in the microstructure with the hardness of the strands and the ZTA. The experiments revealed that a single soldering pass is sufficient for the formation of delta ferrite in the form of a net along the weld bead and in the regions exposed to high temperatures in the thermally affected zone (ZTA), as well as the hardness profile of the section cross section of the weld beads indicate hardness ranging from 344 ± 6 HV to the molten region, passing through a hardness peak of 379 ± 4 HV in the ZTA and ending in the base metal with 290 ± 5 HV, in the multipass weld the origin of the different In the present study, the ferrite morphologies are multiple, with a difference in the cooling rate in the cords, between the base and the top of the weld it is possible to detect the accumulation of delta ferrite in the interpass region and at the top of the last weld bead and the ZTA The thermally affected zone delta ferrite (ZTA) morphology in the multipass condition, as well as the cross section hardness profile of the weld beads, point to hardnesses that vary from 311 ± 24 HV for the molten region, passing through a hardness peak of 326 ± 33 HV in the ZTA.

A habilidade de prever mudanças morfológicas nas regiões costeiras é restringida pela falta de dados observacionais com suficiente resolução espacial e temporal. Com o desenvolvimento do sensoriamento remoto, esse problema pode ser minimizado, especialmente com o uso de câmeras de vídeo para o estudo de regiões costeiras. Os objetivos dessa tese são, através do uso de imagens de vídeo, (1) desenvolver um método robusto para extrair a localização da linha de costa; (2) analisar um conjunto de dados inéditos de 26 anos de imagens diárias; (3) caracterizar as escalas espaciais e temporais da variação da linha de costa em um local representativo, a praia de Duck, NC; (4) testar esse método em uma praia reflectiva e com cúspides, a praia de Massaguaçu localizada no litoral brasileiro; (5) descrever recentes observações de feições morfológicas de meso-escalas associadas a um canal de marés usando uma técnica óptica inovadora e documentar as taxas e padrões de migração dessas feições morfológicas em New River Inlet, NC. Um modelo foi desenvolvido, chamado ASLIM (Augmented ShoreLine Intensity Maxima) para extrair as posições da linha de costa baseado na intensidade máxima observada nas imagens de exposição (timex) através de um ajuste Gaussiano com um subsequente filtro Kalman filtro, este para reduzir incertezas e ruídos. O ASLIM quando comparado com dados do levantamentos batimétricos mostrou um boa correlação com coeficiente de 0.85, estatisticamente significativo). As ondas foram caracterizadas em termos da altura significativa e os componentes longitudinal e transversal do fluxo de energia da onda (Px e Py, respectivamente). Menos de 2\\% da altura da onda é explicada por escalas maiores do que um ano. 66\\% da variância foi explicada por períodos maiores do que o ciclo anual, apesar do fato das forçantes (ondas) serem dominadas por períodos curtos (menores que 20 dias). O primeiro modo da EOF para a variação da linha de costa contém 49\\% da variância e representou o movimento transversal da linha de costa. O segundo modo (26\\% da variância) está associado com a alternância de sinais de acresção em cada lado píer, enquanto que os modos mais altos (7\\% e 5.6\\%) descrevem os efeitos locais do píer. O píer apresentou uma influência significativa no comportamento da linha de costa, à qual estende-se a 500 metros ao norte e sul do píer, duas vezes mais do que os valores assumidos por estudos anteriores. O píer restringe o transporte longitudinal sazonal entre a parte sul (verão) e a parte norte (inverno), resultando em uma acumulação de sedimentos sazonalmente reversa no lado up-drift da deriva. Sinais de erosão foram encontrados ao lado down-drift do píer e que propagam-se 1200 m/ano para longe do píer. A linha de costa apresentou uma tendência à erosão apenas no lado norte do píer, esta erosão pode estar relacionada com a tendência de aumento do transporte longitudinal para o norte, que é bloqueado devido ao píer, gerando uma acumulação na parte sul do píer e erosão na parte norte. O método ASLIM também foi testado na Praia de Massaguaçu e mostrou ser uma valiosa ferramenta para investigar variabilidade da linha de costa. Nossas observações em New River Inlet (NC), revelaram um complexo de bancos de espraiamento e feições arenosas de meso-escalas que migraram em um padrão coerente horário onde nas regiões offshore migraram em direção contrária a desembocadura do rio enquanto que as feições na região próxima a costa, migraram em direção ao canal. Para quantificar de forma objetiva as taxas e padrões de migração um algoritmo foi desenvolvido (LLSA - Lagged Least Square Algorithm) usando sequências de imagens de exposição (timex). Esse método compara diferentes imagens que possuem diferentes intervalos de tempo, e encontra o intervalo (lag) onde essas imagens são similares. A taxa média de migração encontrada foi de 1.53 m/dia (com desvio padrão de 0.76 m/dia). 72\\% das taxas estimadas foram maiores que 1.0 m/dia, 31\\% foram maiores que 2 m/dia, e as taxas máximas encontradas foram 3.5 m/day, em 23 dias. As taxas de migração média longitudinais mostraram um nó em 110 metros da linha de costa que separa as feições que migram para longe do canal (offshore) e para a linha de costa. O padrão circular pareceu ser consistente com o fluxo residual esperado em um delta de maré vazante. Em conclusão, nossos resultados mostraram que o uso de câmeras de vídeo são uma ótima ferramenta para fornecer informações sobre a dinâmica de morfologias costeiras com alta resolução temporal e espacial, de curto à longo-prazo. / The ability to predict changes of the coastal morphology has been restricted by the lack of observational data in a sufficient spatial and temporal coverage. With the advent of remote sensing, the low spatial and temporal resolution could be overcome, especially with the development of video cameras to study nearshore environments. The goals of this thesis are, using remote sensing techniques, to (1) develop a robust method for extracting shoreline locations; (2) analyze a unique 16 and 26-year record of daily to hourly video images; (3) characterize the space-time scales of shoreline variability at a representative site at Duck, NC; (4) test this method at a reflective and cuspy beach at Massaguaçu Beach located at Brazilian coast; (5) describe recent observations of meso-scales morphology associated with tidal inlets using an innovative optical method and document rates and patterns of migration of these features at New River Inlet, NC. A model was developed, called ASLIM (Augmented ShoreLine Intensity Maxima) to extract the shoreline positions based on fitting the band of high light intensity in time exposure images to a local Gaussian fit with a subsequent Kalman filter to reduce noise and uncertainty. The ASLIM model showed good agreement with survey data (correlation coefficient of 0.85, significant at 95\\% confidence level). Wave forcing was characterized in terms of the significant wave height and the cross-shore and longshore components of wave energy flux. 66\\% of the shoreline variability was explained by periods longer than the annual cycle, despite the fact that wave forcing is dominated by shorter periods. The first EOF mode of shoreline variability contained 49\\% of the variance and represented the cross-shore movement (landward- seaward) of the shoreline. The second mode (26\\% of the variance) is associated with alternating accretion signals on either side of the pier, while the next two higher EOFs (7\\% and 5.6\\%) describe the local pier effects. The pier was found to have a significant influence on shoreline behavior that extends out to 500 meters, nearly twice the length scales assumed by previous studies. The pier restricts seasonal longshore transport from the south (summer) and north (winter) sides, resulting in a seasonally-reversing sediment accumulation on the up-drift side. Erosion signals on the down-drift side of the pier were found propagate away from the pier at 1200 m/year. A shoreline erosion trend that was found only on the north side of the pier may be related to the trend found in the alongshore transport, that it is increasing toward the north and is being blocked by the pier. The ASLIM method was also tested at Massaguaçu Beach and showed to be a valuable tool to investigate shoreline variability processes. Our observations, at New Rivet Inlet (NC), revealed a complex set of swash bars and meso-scale sand banks that migrated in a coherent clockwise pattern with movement in offshore regions being away from the inlet mouth while nearshore migration was back toward the inlet. To quantify migration rates and patterns objectively based on sequences of time exposure images, a Lagged Least Squares Algorithm (LLSA) was developed that found the vector migration rate for which the suite of lagged images were most similar, computed on a tile-by-tile basis. The mean migration rate was found to be 1.53 m/day (standard deviation of 0.76 m/day). 72\\% percent of estimated rates were greater than 1.0 m/day, 31\\% percent were larger than 2.0 m/day, and the maximum rate round was 3.5 m/day, averaged over 23 days. Alongshore averages of cross-shore migration rates showed a node at 110 m from the shoreline that separates migration away from the inlet (offshore) from migration toward the inlet near the shore. The circular pattern of migration appeared to be consistent with expected residual flow on an ebb delta. In conclusion, our results showed that the use of video cameras are a useful tool for providing information about the dynamics of coastal morphologies with a high temporal and spatial resolution, from short to long-term.

Ce travail de thèse porte sur le développement d’une méthodologie efficace pour la conception analogique, des algorithmes et des outils correspondants qui peuvent être utilisés dans la conception dynamique de fonctions linéaires à temps continu. L’objectif principal est d’assurer que les performances pour un système complet peuvent être rapidement investiguées, mais avec une précision comparable aux évaluations au niveau transistor.Une première direction de recherche a impliqué le développement de la méthodologie de conception basée sur le processus d'optimisation automatique de cellules au niveau transistor et la synthèse de macro-modèles analogiques de haut niveau dans certains environnements comme Mathworks - Simulink, VHDL-AMS ou Verilog-A. Le processus d'extraction des macro-modèles se base sur un ensemble complet d'analyses (DC, AC, transitoire, paramétrique, Balance Harmonique) qui sont effectuées sur les schémas analogiques conçues à partir d’une technologie spécifique. Ensuite, l'extraction et le calcul d'une multitude de facteurs de mérite assure que les modèles comprennent les caractéristiques de bas niveau et peuvent être directement régénéré au cours de l'optimisation.L'algorithme d'optimisation utilise une méthode bayésienne, où l'espace d’évaluation est créé à partir d'un modèle de substitution (krigeage dans ce cas), et la sélection est effectuée en utilisant le critère d’amélioration (Expected Improvement - EI) sujet à des contraintes. Un outil de conception a été développé (SIMECT), qui a été intégré comme une boîte à outils Matlab, employant les algorithmes d’extraction des macro-modèles et d'optimisation automatique. / The aim of this thesis is to establish an efficient analog design methodology, the algorithms and the corresponding design tools which can be employed in the dynamic conception of linear continuous-time (CT) functions. The purpose is to assure that the performance figures for a complete system can be rapidly investigated, but with comparable accuracy to the transistor-level evaluations. A first research direction implied the development of the novel design methodology based on the automatic optimization process of transistor-level cells using a modified Bayesian Kriging approach and the synthesis of robust high-level analog behavioral models in environments like Mathworks – Simulink, VHDL-AMS or Verilog-A.The macro-model extraction process involves a complete set of analyses (DC, AC, transient, parametric, Harmonic Balance) which are performed on the analog schematics implemented on a specific technology process. Then, the extraction and calculus of a multitude of figures of merit assures that the models include the low-level characteristics and can be directly regenerated during the optimization process.The optimization algorithm uses a Bayesian method, where the evaluation space is created by the means of a Kriging surrogate model, and the selection is effectuated by using the expected improvement (EI) criterion subject to constraints.A conception tool was developed (SIMECT), which was integrated as a Matlab toolbox, including all the macro-models extraction and automatic optimization techniques.

La plasticité mitochondriale à l'égard de l'oxydation de substrats, et sa participation à la transition métabolique ont été étudiées dans deux conditions: l'exposition chronique à l'hypoxie et l'entraînement en endurance, connues comme modulatrices de la préférence de substrats. Ainsi l'affinité pour le palmitoyl carnitine est augmentée par l'hypoxie et la restriction calorique alors qu'au contraire le flux maximal de palmitoyl CoA (PCoA) semble freiné par l'hypoxie. Quant aux effets de l'entraînement, malgré une amélioration du temps limite de course à intensité sous-maximale et une augmentation des capacités oxydatives globales, nous ne retrouvons pas de facilitation de l'oxydation du PCoA. Par ailleurs, on observe une augmentation des messagers PPAR-delta et d'UCP-3 en réponse à une exposition aigue à l'hypoxie. Le rôle de PPAR-delta sur la modulation de l'utilisation de substrats par la mitochondrie a aussi été envisagé en utilisant un agoniste pharmacologique de PPAR-delta, le GW 742. Celui-ci, permet d'améliorer l'efficacité catalytique du complexe enzymatique CPT-1 tout en limitant l'oxydation du pyruvate, également diminuée dans les muscles oxydatifs au cours de la restriction calorique. Le traitement par GW 742, s'il limite l'altération de l'efficacité catalytique de CPT-1 observée en hypoxie, ne permet pas de rétablir, un niveau d'oxydation en PCoA similaire à celui observé en situation contrôle. Le GW 742 s'est aussi montré capable de restaurer le flux en PCoA altéré par l'entraînement, même si la fonction du transport CPT-1 reste limitante devant l'augmentation du potentiel oxydatif induit par l'entraînement. Par ailleurs, nous n'avons pas retrouvé de relation étroite entre les variations d'affinité en PCoA et la performance aérobie sous-maximale, pourtant influencée par la capacité à oxyder préférentiellement les lipides. Enfin, la diminution du flux en pyruvate associée à l'augmentation de l'utilisation des acides gras à longue chaîne observée lors du traitement par GW 742 ou au cours de la restriction calorique pose la question du rôle joué par une cible particulière de PPAR-delta sur la mitochondrie, la protéine découplante UCP-3. / Substrate oxidation and its contribution to metabolic shift, as markers of muscle plasticity have been studied under two specific condition, the prolonged exposure to ambient hypoxia, and endurance training, two conditions known as leading to changes in substrate use. Our result show that the affinity for palmitoyl carnitine is increased by both hypoxia and food restriction, whereas in contrast exposure to hypoxia slow down the palmitoyl CoA (PCoA) maximal use. On the other hand, endurance training led to enhanced physical performance and increased muscular oxidative capacities, but failed to enhance PCoA oxidation. The transcripts for PPAR-delta and UCP-3 increased in response to aucte exposure to hypoxia. Moreover, we studied the role played by PPAR-delta on the substrate use modulation, using new PPAR-delta agonist known as GW 742. In the present study, this new pharmacological substance has been shown to enhance the catalytic efficiency of CPT-1 and decrease the pyruvate oxidation. Moreover, GW 742 administration limits the hypoxia-induced decrease of CPT-1 activity, but failed to recover levels of PCoA oxidation similar to those observed in control conditions. GW 742 administration was able to suppress the effects of training on maximal PCoA oxidation, even if the functional CPT-1 activity remains limiting regarding the training-induced increase in oxidative capacity. On the other hand, we failed to show strong relationship between PCoA affinity and physical performance. Finally, the concomitant increase in long chain fatty acid oxidation and decrease in pyruvate oxidation resulting from either GW 742 use or food restriction, addresses the issue of the role played by the uncoupling protein UCP-3 on mitochondrial function