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Maîtrise de l'assemblage et des exigences fonctionnelles des systèmes hyperstatiques déformables : application aux outils de mesures pour forage pétrolier / Control of assemblies and functional requirements of overcontrained mecanisms of deformable parts : application on measurement tools for oil drillingRouetbi, Oussama 24 May 2017 (has links)
Ces travaux de recherche sont réalisés dans le cadre d’une thèse CIFRE en collaboration entre Schlumberger et le LURPA de l’ENS Cachan. Schlumberger est une entreprise de service pétrolier. Elle développe des outils de mesures fonctionnant sous des conditions sévères de température et pression élevées mais aussi des effets dynamiques tels que des accélérations produisant des chocs entre les différentes pièces.L’objectif de la thèse est de déployer de nouvelles règles de cotation, pour des assemblages hyperstatiques déformables, basées sur la méthode CLIC et les normes ISO. La déformation des pièces dépend considérablement des défauts géométriques. Nous avons donc couplé des modèles de chaînes de cotes 3D avec des modèles RdM de type poutre afin d’optimiser les tolérances. Ces modèles doivent permettre la prise en compte des jeux d’assemblage dans les liaisons, la rigidité des pièces et les différents types de contact entre les sous-ensembles des outils étudiés.Ces modèles multi-physiques ont permis de caractériser le comportement mécanique en fonction des écarts géométriques des pièces. Enfin, pour des études plus complexes, des modélisations et simulations éléments finis, sur Abaqus, ont été réalisés puis validées par une campagne expérimentale de comportement au choc. / This research is carried out within a CIFRE doctoral thesis in collaboration between Schlumberger and the LURPA of ENS Cachan. Schlumberger is an oil service company. It develops measurement tools operating under severe conditions of high temperature and pressure but also dynamic effects such as accelerations producing shocks between the different parts.The objective of the thesis is to deploy new dimensioning and tolerancing rules for deformable hyperstatic assemblies, based on the CLIC method and the ISO standards. The deformation of the parts greatly depends on the geometrical defects. We have coupled 3D dimension chains with beam models to optimize tolerances. These models must allow the taking into account of the assembly clearances between parts, their rigidity and the different types of contact between the subassemblies of the studied tools.These multi-physical models allowed to characterize the mechanical behavior as a function of the geometrical deviations of parts. Finally, for more complex studies, finite element models and simulations on Abaqus were carried out and then validated by an experimental campaign of impact behavior.
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Identification des mécanismes physiopathologiques de la dystrophie facioscapulohumérale : rôle de la mitochondrie et du stress oxydant / Identification of pathophysiological mecanisms of facioscapulohumeral muscular dystrophy : involvement of mitochondria and oxidant stressTurki, Ahmed 06 December 2012 (has links)
La dystrophie facioscapulohumérale (FSHD) est une dystrophie musculaire autosomique dominante, dégénérative et progressive. Les traitements élaborés jusqu'à présent n'ont pas réussi à améliorer le quotidien des patients FSHD. Plusieurs études se sont focalisées sur les mécanismes moléculaires de cette pathologie, néanmoins plusieurs d'entre elles sont contradictoires. La vision actuelle de la FSHD est celle d'une pathologie due à un mécanisme épigénétique complexe et les mécanismes moléculaires responsables de cette pathologie sont encore mal connus. Plusieurs analyses comparatives des profils d'expression des ARNm et des protéines de muscles de patients atteints de FSHD et de contrôles ont permis de montrer que plusieurs gènes impliqués dans le stress oxydant sont dérégulés de façon spécifique dans les muscles FSHD. Nos travaux ont permis de montrer dans la FSHD, aussi bien au niveau systémique, musculaire et cellulaire (cultures primaires musculaires) une augmentation des dommages oxydatifs qui se traduisent par une augmentation des peroxydes lipidiques et protéines oxydées, associés à une altération des défenses antioxydantes. Ce stress oxydant dans les biopsies musculaires et cultures primaires musculaires est associé à un dysfonctionnement mitochondrial. Des analyses plus fines sur l'action des espèces réactives de l'oxygène et leurs sources pourraient contribuer à une meilleure compréhension des bases physiopathologiques de la FSHD et permettre la sélection de thérapeutiques adaptées aux anomalies des patients FSHD. / Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal inherited muscular dystrophy. Actually no treatment led to improve the quality of life. Many studies have been focused on the molecular mechanisms of this disease, several of them were contradictory. The present view of the FSHD seems to be due to a complex epigenetic mechanism. Actually, no gene has been identified. Several comparative studies permit the identification of many genes involved in oxidative stress, deregulated in FSHD myoblasts and biopsies in comparison to healthy ones. Analysis of oxidative stress markers show that patients with FSHD present increased oxidative damage in blood as well as in biopsy muscle and muscular primary cell culture associated with altered antioxidant enzyme defenses. Oxidative stress is also associated with mitochondrial dysfunction. Complementary studies focusing in pathway of reactive oxygen species would contribute to a better understanding of pathophysiological bases of FSHD in order to establish a very helpful therapeutics for FSHD patients.
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Stimulation magnétique transcranienne du cortex moteur a visée antalgique : recherche clinique, approche des mécanismes, effet placebo, valeur pédictive / Transcranial magnetic stimulation of motor cortex for pain relief : clinical research, approach to mechanisms, placebo effect, predictive valueAndré-Obadia, Nathalie 02 December 2013 (has links)
La stimulation magnétique répétitive transcrânienne (rTMS) du cortex moteur à visée antalgique réunit deux conditions extrêmement intéressantes: un accès non invasif à une cible corticale éloquente et, par la modulation de son activité, la possibilité d'influencer le transfert et l'intégration du message nociceptif. L'objectif de cette thèse est d'évaluer comment une approche de recherche clinique permet à la fois de progresser dans la compréhension des mécanismes qui sous-tendent l'effet antalgique de la rTMS et d'optimiser cet effet chez le patient. Une première étude paramétrique, concernant la technique de stimulation, a montré que l'orientation du courant était cruciale pour le développement d'un effet antalgique, l'orientation la plus favorable étant celle activant des interneurones corticaux. Nous n'avons toutefois pas objectivé de modification spécifique d'une composante sensorielle de la douleur en rapport avec cet effet local, ni une influence liée au caractère somatotopique de la stimulation. Ainsi, l'efficacité de la stimulation ne semble pas tributaire de sa localisation en regard de la représentation corticale du territoire douloureux. L'action sur la composante sensorielle de la douleur n'expliquant pas à elle seule l'effet antalgique de la rTMS, nous avons analysé les interactions entre effet antalgique et effet placebo : la rTMS a une efficacité propre, indépendante de l'effet placebo et lorsqu'elle est efficace, elle majore l'effet d'une séance placebo réalisée par la suite, par un phénomène de conditionnement. La rTMS active facilite les mécanismes de contrôle central de la douleur grâce à ses connexions à distance et à son action sur les systèmes endorphiniques, également impliqués dans l'effet antalgique du placebo. A la lumière de ces résultats, nous avons analysé les critères cliniques sur lesquels reposent l'efficacité à long terme des procédures de stimulation épidurale antalgique du cortex moteur et la valeur prédictive de la rTMS: l'efficacité de la rTMS apparaît comme un marqueur utile pour prédire l'efficacité au long cours de la stimulation corticale épidurale, lorsque la douleur est évaluée non seulement dans sa dimension sensorielle pure mais également à travers son retentissement psychologique global. L'ensemble de ces travaux suggère une action multiple de la rTMS s'exerçant probablement dans les 3 sphères (sensori-discriminative, affective et cognitive) qui sous- tendent la perception et le vécu de la douleur chronique / Repetitive transcranial magnetic stimulation (rTMS) of the motor cortex allows a non- invasive access to an eloquent cortical area and, by the modulation of its activity, the possible interference with central integration of pain. ln this thesis we have applied clinical research methods to enhance the understanding of the mechanisms of pain relief by rTMS and to optimize its clinical effect in chronic pain patients. A first parametrical study, concerning technical aspects of the stimulation, showed the crucial role of current orientation to increase the magnitude of analgesic effects, a postero-anterior orientation promoting interneuronal activation being superior to a latero-medial direction. We found neither a selective modification of sensorial component of pain nor a somatotopic effect of the stimulation: indeed, rTMS analgesic efficacy was not dependent upon stimulation being applied to the cortical representation of the painful territory. The impossibility to explain the whole analgesic effect of rTMS by an isolated modulation of sensory components of pain prompted us to study the interactions between real and placebo rTMS analgesic effects. Active rTMS has a specific analgesic effect, and, when efficacious, it was able to enhance the placebo effect of subsequent sham stimulation. The value of rTMS to adequately predict the long-term efficacy of invasive motor cortex epidural stimulation (surgically implanted MCS) was assessed in a further study. The analgesic efficacy of single-point rTMS proved to be useful to predict the long-term outcome of surgically implanted MCS, provided that such outcome assessment was not exclusively founded on pain intensity but also on the psychological consequences of chronic pain. These results suggest that rTMS exerts its analgesic effects at multiple levels, and probably modifies the 3 different spheres (sensori-discriminative, affective and cognitive) at the origin of perception and consequences of chronic pain in daily life
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Organizações Patológicas e Equilíbrio Psíquico em Pacientes Diabéticos Tipo 2 / Pathological Organizations and Psychological Balance in Patients with Type II DiabetesHeleno, Maria Geralda Viana 13 December 2000 (has links)
Através da prática clínica, notamos em alguns pacientes diabéticos uma resistência paralisadora crônica que impede o tratamento. Eles parecem não se darem conta do que se passa com eles e vivem como se o não tratamento fosse algo bom. Sentem-se protegidos e têm a convicção de que nada irá acontecer-lhes. Eles garantem que não sentem nada, nenhum sinal de complicação aguda ou crônica. Pensamos que esta proteção perversa pode ser compreendida a partir do estudo das organizações patológicas. Elas oferecem grande resistência a mudanças e a experiências de dependência de objeto. Os objetivos desta pesquisa foram: (1) avaliar o grau de eficácia adaptativa e os episódios de crise; (2) avaliar a dinâmica emocional e o equilíbrio adaptativo do ego, visando a compreensão do sistema tensional inconsciente principal, que pode identificar, ou não, a presença das organizações patológicas; (3) correlacionar o grau de eficácia adaptativa com a presença ou não das organizações patológicas; (4) correlacionar o grau de equilíbrio adaptativo do ego com a intensidade da ação das organizações patológicas e (5) correlacionar a qualidade do controle glicêmico com a presença ou não das organizações patológicas. Os instrumentos utilizados foram a Escala Diagnóstica Adaptativa Operacionalizada - EDAO e O Teste das Relações Objetais de Phillipson - TRO. O controle da glicemia foi determinado através de exames de laboratório. Foram sujeitos desta pesquisa 30 pacientes diabéticos do tipo 2, amostra representativa e imparcial de uma população de 113 pacientes diabéticos atendidos no primeiro semestre de 1999 na Liga dos estudantes para o atendimento do pacientes diabético - LIGA, do Centro de Diabetes da Universidade Federal de São Paulo - UNIFESP. Os sujeitos, de ambos os sexos, tinham idade entre 44 e 62 anos e foram divididos em dois grupos. O grupo I era formado por 15 pacientes com bom controle glicêmico e o grupo II, por 15 pacientes com mau controle. Os dois grupos foram controlados por seis meses, durante os quais as recomendações da Sociedade Brasileira de Diabetes - SBD(1999) foram utilizadas para determinar a qualidade do controle glicêmico. A partir deste critério os grupos foram definidos. Os pacientes com glicose plasmática de jejum (GJ) < 126 mg/dl e Glicose Casual (GC) < 200 mg/dl foram considerados de bom controle e formaram o Grupo I. Acima ou igual a estes valores, Grupo II, de mau controle. Os resultados mostraram que existe forte correlação entre a eficácia adaptativa e o equilíbrio interno do ego com a qualidade do controle glicêmico. Assim, quanto melhor o nível da adaptação, melhor o controle glicêmico. Da mesma forma, quando as relações de objeto tendem à adaptação ou são positivas, melhor o controle glicêmico. Quanto à presença das organizações patológicas, a análise através da EDAO e do TRO mostrou que no Grupo I, de bom controle, não foi observada a presença destas organizações. Estes pacientes apresentavam respostas que, cumulativamente, geravam a melhora ou manutenção da eficácia adaptativa. O equilíbrio do mundo interno gerava a possibilidade de adaptação às situações. No Grupo II, de mau controle, pôde-se observar a presença e a intensidade das organizações patológicas. Estes pacientes apresentavam respostas que impediam qualquer tipo de progresso, reduzindo de forma significativa a eficácia adaptativa. No TRO, da mesma forma, observou-se no Grupo II a imobilização ou paralisação frente às situações, fenômeno característico das organizações patológicas. / We observed, through clinical practice, that some diabetes patients presented a chronic paralyzing resistance which blocks treatment. They do not seem to realize what is going on with them and live as if the treatment were not a beneficial thing. They feel protected and are sure that nothing will happen to them. They assure that they do not feel anything, any signs of either acute or chronic complications. We think that such wicked protection can be understood from the study of the pathological organizations. These organizations offer great resistance to changes and object-dependant experiences. The purposes of this study were: (1) to assess the level of adaptive effectiveness and the crisis episodes; (2) assess the emotional dynamics and the adaptive balance of the ego, aiming at understanding the main unconscious stressing system, which might identify the presence or absence of pathological organizations; (3) to correlate the level of adaptive effectiveness with the presence or absence of pathological organizations; (4) to correlate the level of adaptive balance of the ego with the intensity of action of the pathological organizations; and (5) to correlate the quality of the control of glycemia with the presence or absence of pathological organizations. The instruments used were the Adaptive Operational Diagnostic Scale (Escala Diagnóstica Adaptativa Operacionalizada EDAO) and the Phillipson Object Relations Test (Teste das Relações Objetais de Phillipson TRO). The control of glycemia was determined by laboratory tests. Along this study, 30 Type II diabetes patients were observed, which represents a significant and impartial sample from a population of 113 diabetes patients treated during the first half of 1999 at the Students league for the treatment of diabetes patients (LIGA), from the Diabetes Center of Universidade Federal de São Paulo - UNIFESP. The patients, from both genders, were aged from 44 to 62 and were divided into two groups. Group I had 15 patients with a good control of glycemia whereas Group II had 15 patients with a bad one. Both groups were controlled for six months, along which they applied the recommendations from the Brazilian Society for Diabetes (Sociedade Brasileira de Diabetes SBD - 1999) in order to determine the quality of the control of glycemia. From this criterion the groups were defined. Patients with Plasmatic Fast Glucose (GJ) < 126 mg/dl and Casual Glucose (GC) < 200 mg/dl were considered as having a good control and so they were part of Group I. Figures above or equal to these values were included in Group II, as having a bad control. The results showed that there is a strong correlation between the adaptive effectiveness and the internal balance of the ego with the quality of the control of glycemia. Therefore, the higher the level of adaptation, the better the control of glycemia. Likewise, whenever the object relations either tend to adaptation or are positive, the better the control of glycemia. As for the presence of pathological organizations, the analysis through EDAO and TRO showed that in Group I, with a good control, such organizations were not observed. These patients presented responses which, on a cumulative basis, generated either the improvement or maintenance of the adaptive effectiveness. The balance of the inner world generated the possibility of adaptation to situations. In Group II, with a bad control, we observed the presence and intensity of pathological organizations. These patients presented responses that blocked any type of progress, thus significantly the adaptive effectiveness. In TRO, likewise, we observed that in Group II the immobilization or paralysis before situations, which is a typical phenomenon of pathological organizations.
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Etude de l'impact des paramètres de protection périphérique et environnementaux de composants de puissance en carbure de silicium en vue de leur montée en tension / Study of the Impact of the Peripheral Protection and of the Environmental Parameters on SiC Power Devices Performance for Higher Voltage RatingWei, Lumei 19 July 2017 (has links)
Actuellement, la majorité des composants à semi-conducteur pour l'électronique de puissance est réalisée à partir de silicium. Afin de répondre aux nouvelles contraintes électriques et thermiques imposées par la montée en tension et en densité de puissance des convertisseurs d'énergie électrique, une solution repose sur l'emploi d'un semi-conducteur à large bande interdite tel que le carbure de silicium (SiC), du fait de son champ électrique critique (EC) environ dix fois plus élevé que celui du silicium et de sa capacité à fonctionner à des températures supérieures à 200 °C. Une revue des nombreuses publications concernant des diodes en SiC de tenue en tension élevée, voire leur disponibilité commerciale (jusqu'à 10 kV), est présentée, qui montre les progrès réalisés grâce aux efforts portés sur l'amélioration du matériau et l'optimisation de la protection périphérique des composants. L'étape de passivation primaire reste une étape critique très souvent mentionnée. Beaucoup moins de travaux prennent en considération l'impact des matériaux de passivation secondaire et d'encapsulation. L'objectif de cette thèse est de contribuer à une meilleure connaissance des paramètres et des mécanismes de rupture impactant la tenue en tension à l'état bloqué de l'ensemble que forment la puce et son l'environnement isolant électrique. Ainsi, une étude expérimentale de l'influence de différents paramètres liés au semi-conducteur ainsi qu'aux matériaux de passivation et d'encapsulation présents en surface de la puce a été menée, à l'aide de diodes en SiC-4H avec protection périphérique par poche implantée, réalisées par la société IBS, dans le cadre du projet de recherche 'FilSiC'. Dans un premier temps, une étude par simulation numérique de l'ensemble de la structure (SiC, électrodes métalliques, isolants) a été effectuée à l'aide du logiciel Sentaurus Device (Synopsys). Elle a permis de quantifier les contraintes en champ électrique dans toute la structure pour une tension appliquée donnée, et leur sensibilité aux caractéristiques des matériaux isolants prises en compte. Cette étude a également servi au choix des paramètres liés au substrat épitaxié et à la géométrie latérale et en surface des diodes (les paramètres technologiques étant fixés par ailleurs), pertinents pour l'étude expérimentale de leur tension de rupture, dans une gamme de 1 kV à 6 kV. En parallèle, la caractérisation électrique, au sein de structures Métal-Isolant-Semi-conducteur, du matériau de passivation primaire utilisé (dépôt épais de dioxyde de silicium), dans une gamme de température jusqu'à 300 °C, a permis de déterminer ses propriétés électriques, dont la rigidité diélectrique. Le travail a ensuite porté sur la caractérisation à température ambiante de la tension de rupture de la structure complète des différentes diodes fabriquées, effectuée sous vide et sous azote à la pression atmosphérique. Les comportements expérimentaux visualisés sous vide au moment du claquage, et couplés aux informations issues des simulations, ont notamment permis d'estimer les valeurs des champs maximaux induits dans les différents matériaux isolants, et de corréler leur impact avec les valeurs de rigidité diélectrique connues pour ces isolants. Les résultats complémentaires sous azote ont permis de confirmer certains paramètres technologiques et mécanismes mis en jeu lors du claquage des diodes d'autre part. Plusieurs conclusions utiles pour l'optimisation des paramètres technologiques (épitaxie et poche) et des couches isolantes de passivation et d'encapsulation (épaisseur, permittivité) de la diode 'haute tension' en SiC ont pu être dégagées de ces travaux. / Nowadays, most of the semiconductor devices used in power electronics are silicon (Si) based devices. In order to meet the new electrical and thermal constraints induced by the demand in rising both the operating voltage and the power density of the electrical energy converters, the use of wide band gap semiconductors such as silicon carbide (SiC) may represent an adequate solution, thanks to their critical electric field (EC) which is about ten times higher than that of Si and to their ability of operating at temperatures beyond 200 °C. A state-of-the-art on the readily (commercially) available high voltage SiC diodes (10kV or higher) is presented, highlighting the progress made in improving the materials themselves as well as their peripheral protection. However, regarding the die insulating materials, the studies mainly focus on the primary passivation step, which was often mentioned as the most critical one. Obviously much less work is carried out on the impact of the secondary passivation and encapsulation materials. The goal of this study is to contribute to a better knowledge of the mechanisms involved in the SiC chips and electrically insulating environment breakdown while in a blocking state, as well as to the identification of the most relevant parameters acting on these phenomena. Thus, a study of the correlated properties of the semiconductor and the passivation and encapsulation materials present on the surface of the chip was carried out on SiC-4H bipolar diodes protected by junction termination extension (JTE), supplied by IBS society, within the framework of the 'FilSiC' research project. First, a numerical simulation study of the entire structure (SiC and insulating materials) was carried out using the Sentaurus Device software (Synopsys). This allowed for quantifying the electric field stresses throughout the structure for a given applied voltage as well as their dependence on the properties of the considered insulating materials. This study was equally used for choosing the appropriate parameters of the epitaxial substrate and for designing the lateral and the surface geometry of the diodes (the technological parameters being fixed elsewhere), in view of the subsequent experimental study of their breakdown voltage in the 1kV-6kV range. Concurrently, the electrical characterization of the primary passivation material used (thick silicon dioxide layer) was performed by using MIS (metal-insulator-semiconductor) type structures, in a temperature range of up to 300 °C. This allowed to determine its main electrical properties, particularly the dielectric breakdown voltage. The work then focused on the room-temperature characterization of the breakdown voltage of the full structures built around the different manufactured diodes. The tests were carried out both under high vacuum conditions and under nitrogen at atmospheric pressure. The behavior of the different study cases observed under vacuum conditions during the breakdown, coupled with the simulation results, allowed to determine the values of the maximum electric fields induced in the different insulating materials and to correlate them to their known dielectric breakdown values. On the other hand, additional results obtained under nitrogen atmosphere confirmed some technological parameters and mechanisms at play during the breakdown of the diodes. Several guidelines for the optimization of these technological parameters (epitaxy and JTE) and of the insulating passivation and encapsulation layers (thickness, permittivity) of the "high voltage" SiC diode were derived from this study.
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Analysis and evaluation of economic policy instruments for environmental control in Mexico / Analyse et évolution des instruments de politique économique pour le contrôle environnemental au MexiqueRuiz Arredondo, José Vicente 17 May 2016 (has links)
La présente thèse analyse les principaux aspects du défi de la durabilité des ressources en eau au Mexique avec l'objectif de contribuer à la littérature économique et d'alimenter par les faits l'élaboration de politiques. Elle est composée de trois chapitres. Le premier chapitre analyse la distorsion causée par les subventions à l'électricité et leurs effets sur la surexploitation des nappes phréatiques. Il contribue à la littérature en fournissant des estimations sur les élasticités prix-croisés liées à la demande d'eau d'irrigation au Mexique. Les résultats montrent que les changements dans le prix de l'eau souterraine affectent la quantité d'eau pompée ainsi que la répartition du travail et des engrais. Le deuxième chapitre étudie les effets des inspections environnementales sur l'extraction illégale de l'eau dans les municipalités mexicaines. Les résultats montrent que le programme d'inspection mené par l'agence de l'eau au Mexique a un impact sur le nombre d'irrigants ne possédant pas de concession valide. Toutefois, des efforts supplémentaires sont nécessaires pour améliorer la capacité des bureaux régionaux et permettre au programme d'avoir un effet substantiel sur la durabilité de l'eau. Enfin, le troisième chapitre aborde certaines des préoccupations liées au changement climatique en analysant les effets des périodes de sécheresse et des inondations sur la migration interne au Mexique. Les résultats montrent que la sécheresse comme les inondations agissent comme facteurs d'incitation à la migration interne. En outre, les écarts de revenu, les homicides, et le niveau d'éducation sont des facteurs clés pour la migration interne. / The sustainability or water resources in Mexico is challenged, among other things, by inadequate regulation tools, limited enforcement capacity, and the uncertainty related to climate change. This thesis analyses key aspects of these challenges with the overall objective of contributing to the economic literature and providing inputs for evidence based policy making. The thesis is composed of three chapters. The first chapter looks at the mechanisms regulating groundwater extraction. In particular, it analyses the distortion caused by electricity subsidies and their effects on groundwater overdraft. It contributes to the existing literature by providing estimates on cross-price elasticities related to irrigation water demand in Mexico. The results of this chapter show that changes in the price of ground water not only affect the amount of water pumped, but also the allocation of labour and fertilizers. The second chapter studies the effects of environmental inspections on illegal water extraction across Mexican municipalities. Results show that the main inspection program led by Mexico's water agency does have an impact on the number of irrigators extracting water without a valid concession. However, further efforts improving the capacity of regional offices are required for this program to have a substantive effect on water sustainability. Finally, the third chapter addresses some of the concerns related to climate change by analyzing the effects of droughts and floods on internal migration trends in Mexico. Results show that both droughts and floods act as push factors for internal migration. In addition, results also show that income differential, murders, and educational attainments are key drivers for internal migration in the country.
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Organizações Patológicas e Equilíbrio Psíquico em Pacientes Diabéticos Tipo 2 / Pathological Organizations and Psychological Balance in Patients with Type II DiabetesMaria Geralda Viana Heleno 13 December 2000 (has links)
Através da prática clínica, notamos em alguns pacientes diabéticos uma resistência paralisadora crônica que impede o tratamento. Eles parecem não se darem conta do que se passa com eles e vivem como se o não tratamento fosse algo bom. Sentem-se protegidos e têm a convicção de que nada irá acontecer-lhes. Eles garantem que não sentem nada, nenhum sinal de complicação aguda ou crônica. Pensamos que esta proteção perversa pode ser compreendida a partir do estudo das organizações patológicas. Elas oferecem grande resistência a mudanças e a experiências de dependência de objeto. Os objetivos desta pesquisa foram: (1) avaliar o grau de eficácia adaptativa e os episódios de crise; (2) avaliar a dinâmica emocional e o equilíbrio adaptativo do ego, visando a compreensão do sistema tensional inconsciente principal, que pode identificar, ou não, a presença das organizações patológicas; (3) correlacionar o grau de eficácia adaptativa com a presença ou não das organizações patológicas; (4) correlacionar o grau de equilíbrio adaptativo do ego com a intensidade da ação das organizações patológicas e (5) correlacionar a qualidade do controle glicêmico com a presença ou não das organizações patológicas. Os instrumentos utilizados foram a Escala Diagnóstica Adaptativa Operacionalizada - EDAO e O Teste das Relações Objetais de Phillipson - TRO. O controle da glicemia foi determinado através de exames de laboratório. Foram sujeitos desta pesquisa 30 pacientes diabéticos do tipo 2, amostra representativa e imparcial de uma população de 113 pacientes diabéticos atendidos no primeiro semestre de 1999 na Liga dos estudantes para o atendimento do pacientes diabético - LIGA, do Centro de Diabetes da Universidade Federal de São Paulo - UNIFESP. Os sujeitos, de ambos os sexos, tinham idade entre 44 e 62 anos e foram divididos em dois grupos. O grupo I era formado por 15 pacientes com bom controle glicêmico e o grupo II, por 15 pacientes com mau controle. Os dois grupos foram controlados por seis meses, durante os quais as recomendações da Sociedade Brasileira de Diabetes - SBD(1999) foram utilizadas para determinar a qualidade do controle glicêmico. A partir deste critério os grupos foram definidos. Os pacientes com glicose plasmática de jejum (GJ) < 126 mg/dl e Glicose Casual (GC) < 200 mg/dl foram considerados de bom controle e formaram o Grupo I. Acima ou igual a estes valores, Grupo II, de mau controle. Os resultados mostraram que existe forte correlação entre a eficácia adaptativa e o equilíbrio interno do ego com a qualidade do controle glicêmico. Assim, quanto melhor o nível da adaptação, melhor o controle glicêmico. Da mesma forma, quando as relações de objeto tendem à adaptação ou são positivas, melhor o controle glicêmico. Quanto à presença das organizações patológicas, a análise através da EDAO e do TRO mostrou que no Grupo I, de bom controle, não foi observada a presença destas organizações. Estes pacientes apresentavam respostas que, cumulativamente, geravam a melhora ou manutenção da eficácia adaptativa. O equilíbrio do mundo interno gerava a possibilidade de adaptação às situações. No Grupo II, de mau controle, pôde-se observar a presença e a intensidade das organizações patológicas. Estes pacientes apresentavam respostas que impediam qualquer tipo de progresso, reduzindo de forma significativa a eficácia adaptativa. No TRO, da mesma forma, observou-se no Grupo II a imobilização ou paralisação frente às situações, fenômeno característico das organizações patológicas. / We observed, through clinical practice, that some diabetes patients presented a chronic paralyzing resistance which blocks treatment. They do not seem to realize what is going on with them and live as if the treatment were not a beneficial thing. They feel protected and are sure that nothing will happen to them. They assure that they do not feel anything, any signs of either acute or chronic complications. We think that such wicked protection can be understood from the study of the pathological organizations. These organizations offer great resistance to changes and object-dependant experiences. The purposes of this study were: (1) to assess the level of adaptive effectiveness and the crisis episodes; (2) assess the emotional dynamics and the adaptive balance of the ego, aiming at understanding the main unconscious stressing system, which might identify the presence or absence of pathological organizations; (3) to correlate the level of adaptive effectiveness with the presence or absence of pathological organizations; (4) to correlate the level of adaptive balance of the ego with the intensity of action of the pathological organizations; and (5) to correlate the quality of the control of glycemia with the presence or absence of pathological organizations. The instruments used were the Adaptive Operational Diagnostic Scale (Escala Diagnóstica Adaptativa Operacionalizada EDAO) and the Phillipson Object Relations Test (Teste das Relações Objetais de Phillipson TRO). The control of glycemia was determined by laboratory tests. Along this study, 30 Type II diabetes patients were observed, which represents a significant and impartial sample from a population of 113 diabetes patients treated during the first half of 1999 at the Students league for the treatment of diabetes patients (LIGA), from the Diabetes Center of Universidade Federal de São Paulo - UNIFESP. The patients, from both genders, were aged from 44 to 62 and were divided into two groups. Group I had 15 patients with a good control of glycemia whereas Group II had 15 patients with a bad one. Both groups were controlled for six months, along which they applied the recommendations from the Brazilian Society for Diabetes (Sociedade Brasileira de Diabetes SBD - 1999) in order to determine the quality of the control of glycemia. From this criterion the groups were defined. Patients with Plasmatic Fast Glucose (GJ) < 126 mg/dl and Casual Glucose (GC) < 200 mg/dl were considered as having a good control and so they were part of Group I. Figures above or equal to these values were included in Group II, as having a bad control. The results showed that there is a strong correlation between the adaptive effectiveness and the internal balance of the ego with the quality of the control of glycemia. Therefore, the higher the level of adaptation, the better the control of glycemia. Likewise, whenever the object relations either tend to adaptation or are positive, the better the control of glycemia. As for the presence of pathological organizations, the analysis through EDAO and TRO showed that in Group I, with a good control, such organizations were not observed. These patients presented responses which, on a cumulative basis, generated either the improvement or maintenance of the adaptive effectiveness. The balance of the inner world generated the possibility of adaptation to situations. In Group II, with a bad control, we observed the presence and intensity of pathological organizations. These patients presented responses that blocked any type of progress, thus significantly the adaptive effectiveness. In TRO, likewise, we observed that in Group II the immobilization or paralysis before situations, which is a typical phenomenon of pathological organizations.
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Multiwavelength study of the flaring activity of the supermassive black hole Sgr A* at the center of the Milky Way / Etudes multi-longueurs d'onde de l'activité du trou noir supermassif SGR A* au centre de notre galaxieMossoux, Emmanuelle 29 September 2016 (has links)
Sgr A*, le trou noir supermassif le plus proche de nous, émet une luminosité quiescente très faible ainsi que des éruptions en infrarouge proche (NIR), rayons X et radio. Cette thèse a pour but d'étudier l'effet du passage de DSO/G2 près de Sgr A* sur les éruptions. J'ai utilisé et amélioré trois méthodes pour l'étude en rayons X : les blocs Bayésiens en deux passes pour détecter les éruptions avec une certaine probabilité, le lissage des courbes de lumières pour diminuer le bruit de Poisson et la méthode de Monte Carlo par chaînes de Markov pour l'ajustement des spectres des éruptions. J'ai contraint les paramètres physiques de la source pour une des 3 éruptions détectées en rayons X en 2011 et pour 3 éruptions détectées en rayons X et NIR durant la campagne multi-longueurs d'onde de février-avril 2014. L'activité en rayons X et NIR de février-avril 2014 correspond à celle observée avant le passage de DSO/G2 près de Sgr A*. J'ai calculé le taux d'éruption intrinsèque en rayons X de Sgr A* en 1999-2015 et détecté une plus faible activité à partir du 28 octobre 2013. L'énergie stockée pendant cette période peut expliquer la plus forte activité observée du 30 août au 9 septembre 2014. / Sgr A*, the closest supermassive black hole, is an extremely low luminosity black hole emitting flares in near-infrared (NIR), X-rays and radio. The goal of this Ph.D. is to study the impact of the pericenter passage of the Dusty S-cluster Object DSO/G2 close to Sgr A* on the flaring activity. I used and improved three methods for the study in X-rays: the two-steps Bayesian blocks method to detect flares with a given false detection probability, the light curve smoothing to reduce the Poisson noise and the Monte Carlo Markov chains method for the fitting of the flare spectra. I constrained the physical parameters of the flaring region for one of the three X-ray flares detected in 2011 and for three NIR/X-ray flares detected during the 2014 Feb.-Apr. multiwavelength campaign. The X-ray and NIR activity during the 2014 Feb.-Apr. is not different from those observed before the DSO/G2 pericenter passage. I computed the intrinsic flaring rate in X-rays from Sgr A* in 1999-2015 and I detected a smaller flaring activity beginning on 2013 Oct. 28. The energy saved during this time period could explain the largest activity observed from 2014 Aug. 30 to Sept. 9.
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Etude multi-échelle des mécanismes d'élaboration de revêtements d'alliage zinc-nickel à base d'électrolytes alcalins : germination, complexation et structures cristallines / Multi-scale approach of alkaline zinc-nickel electroplating mechanisms : nucleation, complexation and crystallographic structureFedi, Baptiste 17 March 2016 (has links)
Les travaux présentés dans ce mémoire ont pour but d’approfondir la compréhension des mécanismes d’élaboration de revêtements électrolytiques de zinc-nickel obtenus à partir d’électrolytes alcalins. Les dépôts de zinc-nickel contenant entre 12% et 16%de nickel, connus pour leur performances anti-corrosion, nécessitent l’utilisation d’agents complexants afin de d’obtenir des formes solubles et réductibles du nickel dans un électrolyte à base de zincates à haut pH. Une étude des mécanismes de complexation a permis d’améliorer la compréhension du rôle respectif des agents complexants et de leurs interactions sur la stabilité des mélanges, ainsi que sur la morphologie de la structure cristalline des revêtements obtenus. Les phases cristallines d’alliages de zinc-nickel électro déposés,contenant entre 1% et 20% de nickel ont été quantifiés par déconvolution de courbes d’oxydation potentio dynamique et par DRX. Cette approche donne accès à une cartographie précise des phases d’alliages obtenus en fonction de la teneur en nickel du dépôt. La stabilité thermique des différentes phases à également pu être évaluée et quantifiée par cette méthode. La formulation des électrolytes ainsi que les paramètres des procédés peuvent modifier les cinétiques de germination des revêtements. Une étude fondamentale des mécanismes de germination par chrono ampérométrie couplée à des méthodes d’identification paramétrique a permis de quantifier l’évolution de certains paramètres de germination d’éléments simples en fonction du potentiel d’électrodéposition. L’étude de la germination d’alliage a mis en évidence que des réactions de décomplexation d’espèces modifient les cinétiques de nucléation, sans permettre d’aboutir à un modèle descriptif complet. / The present work aims to deepen the understanding of the mechanisms of zinc-nickelelectrodeposition in alkaline baths. Zinc-nickel deposits containing between 12% and 16%nickel known for their anti-corrosion performance. Complexing agents are required toobtain soluble and reactive nickel forms, and to stabilize the electrolytes. A study ofthe complexing mechanisms has improved the understanding of their respective role andbehavior, and their influence on the stability and the morphology and crystalline structureof the coatings obtained. The crystalline phases of electroplated zinc-nickel alloys in therange from 1% to 20% nickel content were quantified by deconvolution of potentiodynamicoxidation curves and XRD. This approach has led to a precise mapping of the alloyphases obtained as a function of the nickel content. The thermal stability of the differentphases has also been evaluated and quantified by this method. The formulation of theelectrolytes and the process parameters may modify the kinetics of coating germination. Afundamental study of the mechanisms of germination by chronoamperometry coupled witha parametric identification allows the quantification of parameter evolution in relation tonucleation phenomenon of simple elements. The study of alloy germination has shownthat decomplexing reactions are able to modify nucleation kinetics, without achieving acomplete comprehensive modeling.
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