SILVA, Ivilane Lima da. Estudo da qualidade de bife bovino submetido à tecnologia sous vide em escala de produção industrial. 2012. 95 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2012 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-10T14:52:27Z No. of bitstreams: 1 2012_dis_ilsilva.pdf: 989056 bytes, checksum: 0745e26a9deb3df7e91de941b1eae9ba (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-10T14:52:39Z (GMT) No. of bitstreams: 1 2012_dis_ilsilva.pdf: 989056 bytes, checksum: 0745e26a9deb3df7e91de941b1eae9ba (MD5) / Made available in DSpace on 2016-06-10T14:52:39Z (GMT). No. of bitstreams: 1 2012_dis_ilsilva.pdf: 989056 bytes, checksum: 0745e26a9deb3df7e91de941b1eae9ba (MD5) Previous issue date: 2012 / The aim of this study was to verify the quality of steak cattle processed in industrial scale using sous vide technology during the sequential steps of the process. Physico-chemical and microbiological analysis were performed with the bovine muscle steaks Supraspinatus in natura, Steaks were spicy and processed by sous vide technology (80°C/5 hours) and stored at 3°C for 0, 15, 30, 45 and 60 days for stability studies. It was also performed sensory evaluation of steaks during storage at 0 and 30 days at 3 ° C to verify the acceptance and the color, aroma, flavor, juiciness, texture, overall impression and attitude of purchase. The stability of sous vide bovine steak allowed to observe a few changes in parameters such as ash, protein, a *, b *, Chroma, Hue, and no changes in L *, moisture and fat during the storage time for 60 days at 3°C. There was no significant difference (p <0.05) between the characteristics of samples for flavor, juiciness, texture and overall impression, however significant difference (p> 0.05) was achieved for color and aroma. The responses for purchase intent showed that consumers rated the samples near the hedonic term (4) corresponding to "I would probably buy", with no significant difference (p> 0.05%) between samples. There were counts of aerobic mesophilic, coliform and fecal coliforms in natura steak, steak seasoned and Listeria monocytogenes in one of five collections of in natura steak, but these microorganisms were not found in any sample submitted to sous vide technology and for stability studies. Spores were detected in aerobic and anaerobic sous vide steak during storage. Thus, treatment (80 °C/5 hours) is not sufficient to make the food free of microorganisms capable of reproduction in the product in non-refrigerated storage conditions. Cooking sous vide a final product provided with a greater retention of nutrients (proteins, fat). The storage for 30 days at 3°C seems to have contributed to the change of the sensory characteristics of the samples. This indicates that the sous vide steaks may be stored successfully for 30 days at 3°C and sensory quality can be acceptable to consumers. The results of this study confirm the technological potential of the Supraspinatus muscle for the preparation of steak sous vide, and the viability of its production and marketing for human consumption. In general, the steak sous vide kept its properties during the storage, being an excellent source of nutrition, especially in regard to protein content. The sous vide technology presents itself as an excellent alternative to the meat market by adding value to the product and maintain their quality characteristics / Este trabalho teve como objetivo estudar a qualidade de bife bovino processado em escala industrial através de tecnologia sous vide durante as etapas sequenciais do processo. Foram realizadas análises físico-químicas e microbiológicas em bife de Músculo bovino Supraspinatus in natura, temperado e processado por tecnologia sous vide (80°C/5horas) e armazenados a 3°C durante 0, 15, 30, 45 e 60 dias, para estudo da estabilidade. Foi ainda realizada avaliação sensorial dos bifes durante armazenamento a 0 e 30 dias a 3°C para verificação da aceitação quanto a cor, aroma, sabor, suculência, textura, impressão global e atitude de compra. O estudo da estabilidade dos bifes bovinos sous vide permitiu observar poucas alterações para os parâmetros de cinzas, proteína, a*, b*, Chroma, Hue e nenhuma alteração para os parâmetros L*, umidade e gordura no decorrer do tempo de armazenamento por 60 dias a 3°C. Não houve diferença significativa (p<0,05) entre as amostras para características de sabor, suculência, textura e impressão global, contudo houve diferença significativa (p>0,05) dos parâmetros de cor e aroma. As respostas para a intenção de compra mostraram que os consumidores classificaram as amostras próximo ao termo hedônico (4) correspondente a “provavelmente compraria”, não havendo diferença significativa (p>0,05%) entre as amostras. Foram encontradas contagens de aeróbios mesófilos, coliformes fecais e coliformes totais no bife bovino in natura, bife bovino temperado e presença de Listeria monocytogenes em uma das cinco coletas de bife in natura, contudo estes micro-organismos não foram encontrados em nenhuma das amostras submetidas à tecnologia sous vide e durante estudo de estabilidade. Foram detectados esporos de aeróbios e anaeróbios nos bifes sous vide durante armazenamento. Desta forma, o tratamento (80°C/5 horas) não é suficiente para tornar o alimento isento de micro-organismos capazes de se reproduzir no produto em condições de estocagem não refrigerada. O cozimento sous vide proporcionou um produto final com uma maior retenção de nutrientes (proteína, gordura). O armazenamento por 30 dias a 3°C parece não ter contribuído para a alteração das características sensoriais das amostras. Isto indica que os bifes sous vide podem ser armazenado com sucesso até a 30 dias a 3°C e ser de qualidade sensorial aceitável para os consumidores. Os resultados deste estudo confirmam o potencial tecnológico do músculo Supraspinatus para a elaboração de bife sous vide, e sua viabilidade de produção e comercialização para consumo humano. De uma forma geral, o bife sous vide manteve suas propriedades ao longo do armazenamento, sendo uma excelente fonte de nutrientes, principalmente no que se refere ao teor de proteína. A tecnologia sous vide apresenta-se como uma excelente alternativa para o mercado de carne, por agregar valor ao produto e conservar suas características de qualidade.

OLIVEIRA, Ticiane Coelho Abreu de. Estudo da qualdiade microbiológica, química, físico-química e sensorial de cenoura (Daucus carot, L.) submetida à tecnologia Sous vide produzida em escala industrial. 2012. 98 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2012 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-28T16:00:36Z No. of bitstreams: 1 2012_dis_tcaoliveira.pdf: 741298 bytes, checksum: 355c053111b742e1184f6a1d19ca4110 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-28T16:00:50Z (GMT) No. of bitstreams: 1 2012_dis_tcaoliveira.pdf: 741298 bytes, checksum: 355c053111b742e1184f6a1d19ca4110 (MD5) / Made available in DSpace on 2016-06-28T16:00:50Z (GMT). No. of bitstreams: 1 2012_dis_tcaoliveira.pdf: 741298 bytes, checksum: 355c053111b742e1184f6a1d19ca4110 (MD5) Previous issue date: 2012 / The carrot is a crop rich in carotenoids, pro-vitamin A, minerals and carbohydrates, and is a food with high nutritional value. Brazil is among the five largest producers and consumers of carrot (Daucus carot L .) in the world, concentrating its production in the Southeast. In search of products more attractive, practical, nutritious and healt hy, the consumer's sous vide technology is an alternative technology for the industry in providing food ready for consumption. The sous vide consists in cooking food packaged in plastic vacuum -sealed, subjected to temperatures lower than 100°C for extended periods of time, chilled quickly and stored under refrigeration. The aim of this study was to evaluate the quality and shelf life of carrots ( Daucus carot L.) diced submitted to sous vide technology, produced on an industrial scale. The samples were subje cted to physical and chemical analysis and chemical, microbiological and with three replications, with five repetitions of the products, and soon after processing by 2, 4, 6 and 8 weeks of storage (3°C). Sensory analysis was carried out on days 0 and 4 weeks, with a repeat. The results indicated a significant difference of 5% (p ≤0.05) in carbohydrate, protein, ash, titratable acidity and chromaticity between the carrot fresh carrot and processed by sous vide technology at time 0. In times of 2, 4, 6 and 8 weeks of storage at 3°C difference was significant (p ≤ 0.05) only for protein and total acidity. In sensory analysis, no significant difference (p ≤ 0.05) in any of the attributes studied. It was also observed that the technology sous vide was effective in eliminating vegetative cells of micro-organisms pathogenic and spoilage, yet not been able to eliminate spores. The carrot processed by sous vide technology retains its nutritional characteristics, sensory, chemical and microbiologically stable for up to eight weeks of storage at 3ºC. / A cenoura é uma olerícola rica em carotenóides, pró-vitamina A, minerais e carboidratos, constituindo um alimento com alto valor nutritivo. O Brasil está entre os cinco maiores produtores e consumidores de cenoura (Daucus carot L.) do mundo, concentrando sua produção na região sudeste. Na busca de produtos mais atrativos, práticos, nutritivos e saudáveis pelo consumidor, a tecnologia sous vide surge como uma alternativa tecnológica para a indústria no fornecimento de pratos prontos para consumo. O sous vide consiste em cozinhar alimentos acondicionados em embalagens plásticas seladas à vácuo, submetidos a temperaturas inferiores à 100°C por longos períodos de tempo, resfriados rapidamente e armazenados sob refrigeração. O objetivo desse trabalho foi avaliar a qualidade e a vida de prateleira de cenouras (Daucus carot L.) cortadas em cubos submetida a tecnologia sous vide, produzida em escala industrial. As amostras foram submetidas as análises físico-químicas e químicas, com três repetições e microbiológicas, com cinco repetições, dos produtos, logo após o tecnologia e por 2, 4, 6 e 8 semanas de armazenamento refrigerado (3ºC). A análise sensorial foi realizada nos tempos de 0 e 4 semanas, com uma repetição. Os resultados indicaram que houve diferença significativa de 5% (p≤0,05) nos carboidratos, proteínas, cinzas, acidez total titulável e na cromaticidade entre a cenoura in natura e a cenoura processada por tecnologia sous vide no tempo 0. Nos tempos de 2, 4, 6 e 8 semanas de armazenamento a 3ºC houve diferença significativa (p≤0,05) apenas nas proteínas e acidez total titulável. Na análise sensorial, não houve diferença significativa (p≤0,05) em nenhum dos atributos estudado. Observou-se também que a tecnologia sous vide foi eficiente na eliminação de células vegetativas de micro-organismos deteriorantes e patogênicos, porém não foi capaz de eliminar esporos. A cenoura processada por tecnologia sous vide conservou suas características nutricionais, sensoriais, químicas e manteve-se estável microbiologicamente até oito semanas de armazenamento à 3ºC.

Submitted by Maike Costa (maiksebas@gmail.com) on 2017-09-06T13:54:32Z No. of bitstreams: 1 arquivototal.pdf: 2157440 bytes, checksum: 83fabc6da127189bb8336246add07f22 (MD5) / Made available in DSpace on 2017-09-06T13:54:32Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2157440 bytes, checksum: 83fabc6da127189bb8336246add07f22 (MD5) Previous issue date: 2015-10-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The sheep bracciola is a meat product made with the meat of the sheep neck, marinated and wrapped, popularly known as the steak turtleneck, which is presented as a choice of meat products derived from ovine. Considered a low commercial value meat, the use of marination and cooking method are alternatives to adding value and offering a differentiated product to the consumer market. This research aimed to develop and evaluate the microbiological quality, physico-chemical and sensory of sheep bracciola subjected to different types of cooking: sous vide, combined oven and autoclave. The microbiological evaluation were assessed total coliforms and thermotolerant, Staphylococcus aureus, sulphite-reducing Clostridium and presence / absence of Salmonella spp. The physicochemical evaluation, the following parameters were analyzed: yield, water holding capacity, cooking loss of weight, color, pH, Aa, texture and chemical composition. Sensory analysis was conducted by 12 panelists trained through a methodology based on the Quantitative Descriptive Analysis (QDA) in which the color attributes, presence of nerves, degree of hydration, sheep aroma, flavor sheep, salty, tenderness, juiciness and fibrousness were studied . The results of the microbiological analyzes revealed the absence of Salmonella spp. and low total coliform counts and thermotolerant, Staphylococcus aureus and sulphite-reducing Clostridium in the samples evaluated. The physical and chemical quality of sheep bracciola showed an excellent nutritional value, for each 100g of sheep bracciola presented an average of 73g of moisture, 1.6 g ash, 16.0 g of protein and 2.6 g of lipid. In the instrumental texture analysis, samples were highlighted subjected to cooking sous vide (70 ° C for 6h, 12h and 24h) and autoclave, the combined oven under the conditions used in this study, were not enough to make it soft , serving as an indicator for the selection of these samples in the sensory evaluation. The sample baked in an autoclave recorded the highest scores on the attributes studied in sensory analysis, highlighting the softness attribute. Thus, it is concluded that the samples ovine bracciola coupled with the use of cooking methods sous vide and the autoclave showed detachable nutritional value, high protein, low fat and high quality for their sensory softness. Also, because it is inexpensive raw material, the use of this by-product of slaughter can generate income for producers, leveraging the goat and sheep farming sector. / A bracciola ovina é um produto cárneo elaborado com a carne do pescoço ovino, marinado e enrolado, conhecido popularmente como bife a rolê, que se apresenta como uma opção de produtos cárneos derivados de ovinos. Como a carne de pescoço é considerada uma carne dura, o uso da marinação e o método de cocção representam alternativas para agregação de valor e a oferta de um produto diferenciado ao mercado consumidor. A presente pesquisa teve como objetivo elaborar e avaliar a qualidade microbiológica, físico-química e sensorial da bracciola ovina submetida a diferentes tipos de cocção: sous vide, forno combinado e autoclave. Na avaliação microbiológica foram realizadas contagens de coliformes totais e termotolerantes, Staphylococcus aureus, Clostridium sulfito-redutor e presença/ausência de Salmonella spp. Na avaliação físico-química foram analisados os seguintes parâmetros: rendimento, capacidade de retenção de água, a perda de peso por cocção, cor, pH, Aa, textura e composição centesimal. A análise sensorial foi conduzida por 12 provadores treinados através de metodologia fundamentada na Análise Descritiva Quantitativa (ADQ) em que os atributos de cor, presença de nervos, grau de hidratação, aroma ovino, sabor ovino, sabor salgado, maciez, suculência e fibrosidade foram estudados. Os resultados das análises microbiológicas revelaram ausência de Salmonella spp. e baixas contagens de Coliformes totais e termotolerantes, Staphylococcus aureus e Clostridium sulfito-redutor nas amostras avaliadas. Na qualidade físico-química, a bracciola obteve médias de 73% de umidade, 1,6% de cinzas, 16,0% de proteínas e 2,6% de lipídeos. Na análise de textura instrumental, destacaram-se as amostras submetidas a cocção por sous vide (70°C por 6h, 12h e 24h) e em autoclave, o forno combinado, nas condições utilizadas nesse estudo, não foram suficientes para torná-la macia, servindo como indicador para a escolha destas amostras na avaliação sensorial. A amostra cozida em autoclave obteve as maiores médias nos atributos estudados na análise sensorial, destacando-se no atributo maciez. Deste modo, conclui-se que foi possível o desenvolvimento de um novo produto, em que as amostras de bracciola ovina aliada ao uso dos métodos de cocção sous vide e autoclave apresentaram destacável qualidade sensorial por sua maciez e suculência. Além disso, por se tratar de matéria prima de baixo custo, o aproveitamento deste subproduto do abate pode gerar lucro para os produtores, alavancando o setor da caprinovinocultura.

Les glandes sous-maxillaires sécrètent au repos la majorité de la salive totale. Parmi ses principales substances la constituant, la salive contient également du glucose. Le but de ce travail de recherche est de tenter de comprendre le mécanisme de transport du glucose dans la salive. Des études immunohistochimiques ont été menées sur tissus sous-maxillaires humains. GLUT1, GLUT4 et SGLT1 ont été détectés au niveau des cellules ductales des glandes sous-maxillaires alors que les cellules acinaires semblent équipées principalement de GLUT1 et SGLT1. GLUT2, dans les cellules ductales humaines, semble présent de manière peu importante.Sur glandes sous-maxillaires de rats, les études d’immunohistochimie, de Western blot et de qRT-PCR ont révélé la présence de GLUT1, de GLUT4 et de SGLT1 au niveau des cellules ductales. Les cellules acinaires, quant à elles, révèlent la présence de GLUT1 et de SGLT1. Les études concernant la capture de glucose et le métabolisme de glucose sur glandes sous-maxillaires de rats ont indiqué que le glucose était transporté par les cellules ductales et les cellules acinaires. Cependant, les cellules ductales transportent plus rapidement le glucose et le métabolisent 2 à 3 fois plus que les cellules acinaires. Les cellules ductales, en présence d’agents inhibiteurs tels que la cytochalasine B ou la phloridzine, capturent moins de glucose par le biais de GLUT1 et SGLT1, respectivement. Dans les cellules acinaires, seule la cytochalasine B inhibe le transport du glucose. SGLT1 semble très peu fonctionnel au niveau des cellules acinaires. L’une des originalités de ce travail repose également sur la mise en évidence de la présence du transporteur GLUT4, insulino-dépendant, dans les cellules ductales de glandes sous-maxillaires. Sur anneaux ductaux, l’insuline a démontré sa capacité à stimuler la capture de glucose. Eu égard à leur localisation préférentiellement basolatérale, la présence de 3 transporteurs (GLUT1, GLUT4 et SGLT1) dans les cellules ductales et de 2 transporteurs (SGLT1 et GLUT1) dans les cellules acinaires devrait permettre à ces cellules de subvenir à leurs besoins métaboliques. Ceci est particulièrement important au niveau des cellules ductales où un remaniement majeur des flux ioniques nécessite un soutien métabolique conséquent, surtout en période prandiale. / Doctorat en Sciences dentaires / info:eu-repo/semantics/nonPublished

Ce travail s'inscrit dans la compréhension du comportement de la sous-surface d'une pièce présentant des hétérogénéités contrôlées, soumise à un chargement de type hertzien sans affecter l'intégrité de sa surface initiale. Le but est de qualifier le champ de contraintes en sous couche. Pratiquement, des défauts de forme cylindrique sont positionnés là où le champ de contraintes est maximal. Le contact est dimensionné pour pouvoir observer, par photoélasticimétrie, les évolutions du champ de contraintes et développer une modélisation numérique pour étudier le comportement statique puis dynamique. Il ressort que la présence d'un trou sur l'axe de symétrie z (x = 0) est le facteur prépondérant. Les caractéristiques qui permettent de diminuer la contrainte de cisaillement sur l'axe de symétrie sont celles qui conduisent à un renforcement de la contrainte de cisaillement maximale dans le massif. Cette dualité nous conduit à proposer un indicateur qui prend en compte, à la fois, la contrainte de cisaillement, l'aplomb du contact et l"évolution de la contrainte maximale dans le massif. La méthodologie de travail a été mise en oeuvre et validée. Les approches analytiques et expérimentales ont permis de valider les modélisations numériques qui sont seules à même de permettre l'étude de nombreux cas. Les perspectives sont nombreuses, avec des incursions possibles en structuration de sous-surfaces, perçage simple, frittage sélectif par laser. Ce doctorat a permis de traiter le cas des défauts circulaires. Dans un autre domaine, le soudage est également un cas d'intérêt pour l'étude du comportement des cordons de soudure présentant des défauts de type porosités ou inclusions. / This research concerns the understanding of the sub-surface behaviour of a component presenting controlled heterogeneities and subjected to a Hertzian type load. The purpose is to qualify the stress field in the subsurface. Practically, defects of cylindrical shape are located where the stress field is maximal in sub surface. The contact is sized to be able to observe, by photoelasticity, the stress field and to develop a numerical model to simulate the behaviour (static and dynamic) of the friction area. It is highlighted that the presence of a hole on the z axis of symmetry (x = 0) is the dominating factor. The characteristics which allow decreasing the shearing stress on the symmetry axis are the ones which lead to a strengthening of the maximal shearing stress in the whole volume. This duality drives us to propose an indicator which takes into account, at the same time, the shearing stress below the contact and the evolution of the maximal stress in the whole volume. The working methodology was implemented and validated. The analytical and experimental approaches allow validating the numeric model which is the only one able to allow the study of numerous configurations. The perspectives are numerous, with possible incursions in structuring of sub-surfaces, simple drilling and selective laser sintering.... In another domain, the welding process is also a case of interest for the study of the behaviour of weld seam presenting defects of porosities or inclusions types

Ce travail est divisé en deux parties: Dans la première partie, on présente un résultat d'intégration dans les espaces localement convexes valable pour une longe classe des fonctions non-convexes. Cela nous permet de récupérer l'enveloppe convexe fermée d'une fonction à partir du sous-différentiel convexe de cette fonction. Motivé par ce résultat, on introduit la classe des espaces ``Subdifferential Dense Primal Determined'' (SDPD). Ces espaces jouissent des conditions nécessaires permettant d'appliquer le résultat ci-dessus. On donne aussi une interprétation géométrique de ces espaces, appelée la Propriété Radon-Nikod'ym de Faces (FRNP). Dans la seconde partie, on étudie dans le contexte d'espaces d'Hilbert, la relation entre la lissité de la frontière d'un ensemble prox-régulier et la lissité de sa projection métrique. On montre que si un corps fermé possède une frontière $mathcal{C}^{p+1}$-lisse (avec $pgeq 1$), alors sa projection métrique est de classe $mathcal{C}^p$ dans le tube ouvert associé à sa fonction de prox-régularité. On établit également une version locale du même résultat reliant la lissité de la frontière autour d'un point à la prox-régularité en ce point. On étudie par ailleurs le cas où l'ensemble est lui-même une $mathcal{C}^{p+1}$-sous-variété. Finalement, on donne des réciproques de ces résultats. / This work is divided in two parts: In the first part, we present an integration result in locally convex spaces for a large class of nonconvex functions which enables us to recover the closed convex envelope of a function from its convex subdifferential. Motivated by this, we introduce the class of Subdifferential Dense Primal Determined (SDPD) spaces, which are those having the necessary condition which allows to use the above integration scheme, and we study several properties of it in the context of Banach spaces. We provide a geometric interpretation of it, called the Faces Radon-Nikod'ym property. In the second part, we study, in the context of Hilbert spaces, the relation between the smoothness of the boundary of a prox-regular set and the smoothness of its metric projection. We show that whenever a set is a closed body with a $mathcal{C}^{p+1}$-smooth boundary (with $pgeq 1$), then its metric projection is of class $mathcal{C}^{p}$ in the open tube associated to its prox-regular function. A local version of the same result is established as well, namely, when the smoothness of the boundary and the prox-regularity of the set are assumed only near a fixed point. We also study the case when the set is itself a $mathcal{C}^{p+1}$-submanifold. Finally, we provide converses for these results.

Le lointain infrarouge (16 µm < λ < 30 µm) est un domaine important pour des applications telles que la détection de large molécules organiques (dont les empreintes d'absorption tombe dans cette gamme de longueur d'onde) et pour la radio-astronomie (oscillateurs locaux pour la détection hétérodyne). Malheureusement, cette fenêtre de transparence atmosphérique, communément appelé la 4eme fenêtre de transparence, est un domaine quasi inexploré.Les LCQ sont des sources de lumière cohérentes, couvrant une gamme allant du moyen infrarouge jusqu'au THz, basées sur l'ingénierie de structures de bandes de matériaux semi-conducteurs. Ils démontrent d'excellentes performances dans le domaine du proche infrarouge mais leur efficacité diminue dans la 4ème fenêtre et au-delà.L'un des buts de cette thèse est le développement d'une nouvelle génération de LCQ capable de couvrir cette zone spectral avec de bonnes performances, en terme de puissance de sortie du dispositif et de température maximale d'opération. Un point clé dans cette optique est l'utilisation d'un nouveau système de matériaux pour ces longueurs d'onde : l'InAs/AlSb. L'avantage de cette solution réside dans sa très faible masse effective : 0,023 m0 (comparée à 0,043 m0 dans les puits d'InGaAs), qui permet d’obtenir un gain plus élevé, résultant dans l'amélioration significative des performances.Une autre approche fondamentalement différente réside dans le régime de couplage fort. L'utilisation d'un temps caractéristique ultra-rapide, associé aux oscillations de Rabi, peut permettre dans un premier temps de réaliser des sources électroluminescentes avec un meilleur rendement quantique (comparé à une transition inter-sous-bandes nue). Les pseudos particules qui découlent du régime de couplage fort dans les transitions inter-sous-bandes (appelés polaritons inter-sous-bandes) peuvent sous certaines limites se comporter comme des bosons. On entrevoit alors la possibilité de réaliser des sources cohérentes basées sur la relaxation d'un condensat polaritonique. / The far infrared (16 µm < λ < 30 µm) is an important area for applications such as detecting wide organic molecules (whose absorption fingerprints falls in this wavelength range) and for radio-astronomy (local oscillator for the heterodyne detection). Unfortunately, the atmospheric transparency window, commonly called the 4th transparency window is almost unexplored.QCL are coherent light sources, covering a range from infrared to THz, based on the engineering of band structures of semiconductors. They have excellent performances in the mid infrared but their effectiveness diminishes in the 4th window and beyond.One aim of this thesis is the development of a new generation of QCL able to cover this spectral region with good performance in terms of output power and maximum operating temperature. A key point in this context is the use of a new material system for these wavelengths: InAs / AlSb. The advantage of this solution is its very small effective mass : 0.023 m0 (compared to 0.043 m0 in the InGaAs wells), which provides a higher gain, resulting in significant performances improvement.Another fundamentally different approach lies in the strong coupling regime. Using an ultra-fast characteristic time associated with Rabi oscillations, can allow the realization of emitting sources with improved quantum efficiency (compared to an bare inter-subband transition). pseudo particles arising from the strong coupling regime in the inter-subband transitions (called polaritons inter-sub-bands) may under certain limits behave as bosons. One then sees the possibility of coherent sources based on the relaxation of a polariton condensate.

Pour améliorer la durabilité des voies ferrées, il a été introduit sur la LGV BPL (Bretagne- Pays de Loire), une couche bitumineuse sous ballast, destinée entre autre à diminuer l’amplitude des accélérations produites par le passage des TGV, ce qui est une cause majeure du tassement de ballast. Afin d'étudier les réponses dynamiques des différentes structures, trois sections avec sous couche bitumineuse, et une section avec sous couche granulaire de la voie BPL ont fait l’objet d’une instrumentation, avec suivi à distance des mesures. L’objectif de ce travail de thèse est d’analyser et de modéliser la réponse des sections instrumentées, et de comparer leur comportement durant la phase de montée en vitesse puis durant la phase d’exploitation commerciale. Les résultats ont indiqué un bon comportement des sections bitumineuses. La comparaison des accélérations obtenues sur les différentes sections a confirmé l’effet positif de la couche bitumineuse sur la stabilité de la voie. Sur la base des mesures de la phase de montée en vitesse, des modélisations de la réponse mécanique des sections de la LGV BPL à l’aide du logiciel ViscoRail ont confirmé la fiabilité du logiciel à reproduire le comportement mécanique des structures. Les mesures de température, de teneur en eau, et de tassements verticaux ont également confirmé le bon comportement saisonnier des structures bitumineuses. Enfin, une extension de ViscoRail est mise en place, pour comparer l’effet de différents types de semelles sous rail, linéaire et non linéaire, sur la réponse de la voie. / To improve railways durability, it has been introduced on the HSL BPL (Bretagne-Pays de Loire), a bituminous layer under ballast, intended among other things to reduce the amplitude of the accelerations produced by highspeed trains circulations, which is a major cause of ballast settlement. In order to study the dynamic responses of the different structures, three sections with bituminous underlayment, and a section with a granular sub-layer of BPL track were instrumented. Measurements are monitored remotely. The objective of this thesis is to analyze and model the response of the instrumented sections, and to compare their behavior during the speed up phase and during the commercial service phase. The results indicated good behavior of bituminous sections. The comparison of the accelerations obtained on different sections confirmed the positive effect of the asphalt concrete layer on the stability of the track. Based on the speed up phase measurements, modeling the mechanical response of the various HSL sections using ViscoRail has confirmed the software’s reliability to reproduce the mechanical behavior of railway structures. Temperature measurements, water content and vertical settlements have also confirmed the good seasonal behavior of bituminous structures. Finally, an extension of ViscoRail is put in place, to compare the influence of different types of rail pads, linear and nonlinear, on the response of the track.

Dans ce mémoire, on présente un espace de la géométrie hyperbolique, le bidisque. On y parle de la géométrie du bidisque et pour ce faire on expose en détail la géométrie du plan hyperbolique. Ensuite, on présente les groupes d’isométries du bidisque pour lesquels on décrit les groupes d’isométrie du plan hyperbolique. Enfin, on donne des conditions nécessaires et suffisantes pour que des sous-groupes cycliques d’isométries du bidisque soient discrets.

An experimental cell was built over the Saint-Tite-des-Caps landfill in order to evaluate the efficiency of a cover with capillary barrier effect (CCBE). The latter is composed of a layer of deinking by-products (DBP) installed over a capillary barrier, which is in turn composed of a layer of coarse sand over a layer of gravel. In order to monitor the performance of this system, lysimeters, tensiometers, water content probes, settlement plates and weather station were installed. Design parameters were selected in such a way that the diversion length (DL) would be attained right before the length of the CCBE (30 m). As for the design of the cell itself, the design of the lysimeters also depended on the unsaturated properties of the materials employed, in particular their hydraulic conductivity functions. The lysimeters were designed in order to remain functional at least during the study period. The water retention curves (WRC) of the materials composing the CCBE were determined in the laboratory. These results allowed obtaining the hydraulic conductivity functions (k-fct), which is the principal element, as far as optimisation of the design of the CCBE and of the lysimeters are concerned. Using the k-fcts, it is possible to evaluate the theoretical DL. Numerical simulations showed that the DL can be significantly altered by slight changes in the parameters used to describe the WRC and the k-fcts. For each material, the WRC was determined using various experimental methods; and they all gave slightly different parameters. This caused the significant variation in the DL. The DL determined based on field data allowed for the selection of the most representative WRC. Analysis of field data, made it possible to show the change in saturated hydraulic conductivity, ksat, of DBP decreased by nearly one order of magnitude, which affected its WRC and k-fct. Field monitoring also shows that the hydraulic barrier remains saturated and that the volume of water reaching the sand/gravel capillary barrier increased progressively, as one moves downslope. Data from the four tensiometers, placed along the sand/gravel interface, and the measured infiltration rates in the 3 lysimeters installed in the gravel layer show that the DL varied between 24 m and 29 m during the 2006 monitoring period. During some short periods in 2007, the DL was greater than the 30 m of the cell. The infiltration rate into the gravel layer at the toe of the slope was continuously lower than 3,0 x 10-9 m/s, i.e. lower than the more stringent standards of low permeability cover design (Règlement québécois sur l'enfouissement et l'incinération des matières résiduelles ). In order to quantify the amount of infiltrating water trough DBP and sand layers, several simulations were performed using by Visual HELP software. Infiltrations rates obtained thereof were used as boundary conditions in steady state simulations of the response of the capillary barrier system. Software SEEP/W and Hydrus were used in these simulations and allowed to check the exactness of the initial design hypotheses and assumptions. As the measured DL is somehow similar to the simulated DL, it was concluded that the design methodology was appropriate. The simulations results also show that much greater DL can be attained using such an alternative cover system, depending on the hydraulic properties of the materials.