Les optiques multicouches pour rayons-X sont généralement constituées de centaines de périodes de couches alternées. L'épaisseur d'une période est de quelques nanomètres. Une multicouche est souvent déposée sur un substrat de silicium avec une taille typique de 60 × 60 × (60~300) mm3. Le rapport de dimensions (~107) entre la taille de l'optique et de l'épaisseur de l'empilement est très élevé et il peut conduire à un très grand nombre d'éléments (~1016). Certains éléments spéciaux avec fonctions de couche sont disponibles dans ANSYS (de 2011), ce qui signifie que les propriétés de chaque couche peuvent être définies. Par l'utilisation des éléments nommés « layer-functioned », le modèle d'analyse thermique-structurelle a été mise en œuvre pour les optiques multicouches. Le nombre d'éléments est réduit par un facteur supérieur à 30 et le nombre effectif de sous-couches gérables par les ordinateurs actuels augmente beaucoup. Basé sur la modèle d'éléments finis de l'optique multicouche, la distribution tridimensionnelle non-uniforme de température peut être simulée avec des paramètres variables de charge thermique, de conditions de refroidissement, de propriétés des matériaux, de géométries du substrat et des films de revêtement. Les contraintes et déformations thermiques peuvent être résolues quantitativement.Des miroirs à réflexion totale et des monochromateurs multicouches refroidis à l'eau et à l'azote liquide ont été étudiés avec des paramètres typiques de charge thermique, de refroidissement et de géométrie. Les effets de refroidissement de l'optique et de la charge thermique du faisceau de rayons-X ont été décrits. Il est montré que les influences de la température sur le revêtement et la déformation sont négligeables. La contrainte dans le substrat n'est que légèrement augmentée (<0.1%). Cependant, des fortes contraintes sont induites dans les couches en raison de la différence de CTE, ce qui peut être critique pour la survie de l'optique. Pour la condition de refroidissement à l'eau, la couche est sous contrainte de compression de plusieurs dizaines de MPa, ce qui est normalement inférieur à la résistance du matériau de la couche. Pour la condition de refroidissement à l'azote liquide, cependant, une grosse contrainte de traction de plusieurs centaines de MPa apparait dans la couche lorsque l'optique est refroidie jusqu'à la température de l'azote liquide (80 K). Cette contrainte de traction peut dépasser la résistance à la traction (UTS) pour certains types de matériaux de couche. La contrainte thermique dans l'optique multicouche dépend de la différence de CTE entre le matériau de la couche et le matériau du substrat, mais elle est indépendante de la différence des CTE entre les différentes sous-couches. En principe, pour minimiser la contrainte thermique, le matériau de revêtement doit avoir un CTE proche de celle du substrat, un module de Young et un coefficient de Poisson plus petits. En outre, une grande résistance du matériau de la couche est bénéfique pour sa capacité à résister à la contrainte thermique.Pour obtenir des informations appropriées sur le comportement des multicouches sous l'influence de la charge thermique, des propriétés telles que le module de Young, le ratio entre CTE et module de Poisson des multicouches sont déterminés indirectement en mesurant la variation de la courbure due au changement de température. Des couches simples de B4C, Pd et Cr et des multicouches [Pd/B4C] d'épaisseurs de l'ordre du nanomètre sont préparées et mesurées. Les résultats expérimentaux montrent que tous les matériaux étudiés présentent un CTE et/ou un module de Young inférieur par rapport aux données dans la littérature. Cela est particulièrement vrai pour les couches minces de B4C. Par conséquent, la contrainte thermique réelle et la contrainte dans les couches de revêtement d'un miroir ou de multicouches optiques sont sensiblement plus petites que les résultats calculés avec les propriétés des matériaux massifs. / Multilayer optics for X-rays typically consists of hundreds of periods of alternating sub-layers coated on a silicon substrate. The thickness of one period of sub-layers is a few nanometers. The silicon substrate is typically a block of 60 mm large, 60 mm wide and 60 to 300 mm long. The high aspect ratio (~107) between the size of the optics and the thickness of the multilayer can lead to a very large number of elements (~1016) for the numerical simulation (by FEA). Some special layer-functioned elements have been developed recently (in 2011) in ANSYS, which means the properties of each layer can be explicitly defined. In this work, the thermal-structural analysis model has been implemented for multilayer optics by use of these layer-functioned elements. The number of meshed elements is considerably reduced by a factor of more than 30 and the number of sub-layers feasible for the present computers is increased significantly. Based on the finite element model of multilayer optics, the non-uniform three-dimensional temperature distribution can be simulated with variable heat load parameters, cooling conditions, material properties and geometries of the substrate and the coating films. The thermal stress and deformation can be solved quantitatively.Single layer coated mirrors and multilayer monochromators cooled by water or liquid-nitrogen are studied with typical parameters of heat-load, cooling, and geometry. The effects of cooling-down of the optics and the X-ray beam heat-load are described. It is shown that the influences from the coating on temperature and deformation are negligible. The stress in the substrate is only slightly increased (<0.1%). However, large layer stresses are induced due to the different thermal expansion coefficients (CTE) between the layer and substrate materials, which are the critical issues for the survival of the optics. For the water cooling condition, the layer is under compressive stress of tens of MPa which is normally less than the strength of the layer material. For the liquid-nitrogen cooling condition, however, large tensile stress of several hundreds of MPa is formed in the layer as the optics is cooled more than 200 K down to the liquid-nitrogen temperature (80K). This tensile stress can exceed the ultimate tensile strength (UTS) for some kinds of layer materials. The thermal stress in multilayer optics depends on the difference in CTE between the layer material and the substrate material, but it is independent on the CTE difference between different sub-layers. In principle, to minimize the thermal stress, the coating material should have a CTE closer to that of the substrate, smaller Young's modulus and Poisson's ratio. Moreover, a higher strength of the layer material is beneficial for its ability to withstand the thermal stress.To acquire appropriate information about the behaviour of thin multilayer films under the influence of thermal loading, material properties such as Young's modulus, Poisson's ratio and CTE, of thin multilayer films are determined indirectly by measuring the curvature change due to uniform temperature change. B4C, Pd and Cr single layers and [Pd/B4C] multilayers of thicknesses in the nanometer range are prepared and measured. The experimental results show that all of the studied materials exhibit lower CTE and/or Young's modulus than expected from bulk data in the literature. This is particularly true for the thin B4C films. Therefore, the real thermal stress and strain in the coating layers of a mirror or multilayer optics are significantly smaller than the calculated results with bulk material properties.results with bulk material properties.

Resumo: O experimento teve por objetivo determinar o efeito da temperatura ambiente e da idade da ave sobre o valor energético do milho. Foram utilizados 288 pintos de corte da linhagem Cobb distribuídos em delineamento experimental inteiramente casualizado com esquema de parcelas subdivididas no tempo, sendo as três temperaturas de criação (fria: 18ºC; termoneutra: 25ºC e quente: 33ºC) as parcelas e as três idades de avaliação (inicial: 11 a 14; crescimento: 25 a 28 e final: 39 a 42 dias) as subparcelas, com seis repetições de seis aves cada. A ração basal para o experimento foi formulada à base de milho e farelo de soja e a dieta teste obtida com substituição de parte da ração basal pelo alimento teste: 40% do milho + 60% da ração basal. Foram calculados os coeficientes de metabolizabilidade aparente e verdadeira da matéria seca, do nitrogênio, do extrato etéreo da dieta teste e os valores de energia metabolizável aparente e verdadeira (EMA e EMV); e corrigidas pelo balanço de nitrogênio do milho (EMAn e EMVn), em kcal/kg, com base na matéria natural. Foram encontrados valores médios de EMAn do milho, para aves criadas em temperatura fria, termoneutra e quente de 3322, 3279 e 3233 kcal/kg, respectivamente, e para as fases de criação inicial, crescimento e final de 3215, 3218 e 3400 kcal/kg, respectivamente. Os valores de energia metabolizável do milho, os balanços e os coeficientes de metabolizabilidade dos nutrientes da dieta teste aumentam com a idade do frango de corte, porém as energias metabolizáveis do milho não foram afetadas pela temperatura ambiente. Os balanços e os coeficientes de metabolizabilidade dos nutrientes da dieta teste foram reduzidos em estresse por calor para aves na fase de crescimento e final / Abstract: The aim of this study was to evaluate the effects of environmental temperature and age of broilers chicks on energy value of corn. Two hundred and eighty-eight Cobb chicks were distributed in a complete randomized design with a splitplot arrangement with six replication of six chicks each, the main plots were the three temperatures (cold: 18°C; thermoneutral: 25°C and hot: 33°C) and age was the secondary plot (initial: 11 to 14, growing: 25 to 28 and final: 39 to 42 days). The basal diet was based on corn and soybean meal. The test diet was produced by replacing the basal diet for test food: 40% of corn + 60% of the basal diet. The coefficient of apparent and true metabolizability of dry matter, nitrogen, ether extract of the test diet and apparent and true metabolizable energies (AME and TME) of corn were calculated and energy values were corrected for nitrogen balance (AMEn and TMEn) of corn, in kcal/kg, as fed basis. The mean values of AMEn observed for broilers chicks in cold, thermoneutral and hot temperature of 3322, 3279 and 3233 kcal/kg, respectively, and the phases initial, growing and final of 3215, 3218 and 3400 kcal/ kg, respectively. The metabolizable energy values of corn, the balance and coefficients of metabolizability of the nutrients of the test diet increased with the age of broiler; however the metabolizable energies were not affected by environmental temperature. The balance and coefficients of metabolizability of the nutrients of the test diet were decreased by heat stress for broiler in the growing and final phase / Orientador: José Roberto Sartori / Coorientador: José Henrique Stringhini / Banca: Antonio Celso Pezzato / Banca: Elisabeth Gonzales / Banca: Valquiria Cação da Cruz / Banca: Nadja Susuna Mogyca Leandro / Doutor

Submitted by (edna.saturno@ufrpe.br) on 2017-04-11T13:06:26Z No. of bitstreams: 1 Florival Protassio da Silva Filho.pdf: 4158399 bytes, checksum: ac4a23673ccfbed069aa0598ebed5c9d (MD5) / Made available in DSpace on 2017-04-11T13:06:26Z (GMT). No. of bitstreams: 1 Florival Protassio da Silva Filho.pdf: 4158399 bytes, checksum: ac4a23673ccfbed069aa0598ebed5c9d (MD5) Previous issue date: 2009-02-26 / This research aimed to investigate the influence of sheep’s coat color on heat toleranceftorage, intake during the and performance of Santa Inês breed. The experiment was conducted in summer season at the Agreste region of Pernambuco State, Brazil.It was used a split-plot amangement in a complete randomized experimental design for the following response variables: retal temperature, respiration rate, body surface and skyn temperature. These measurements were performed both during the morning and afternoon. Sweating rate was measured in the afternoon. Heat tolerance index of the animals was avaliated weekely in a completel randomized design. Forage intake was estimated. The environment was monitorated daily by a meteorological station installed close to the experimental paddock and the thermal confort index was calculated. White sheeps showed a small superiority their heat tolerance than the others but his performance did not differ from sheep with chestnut and black hair coat colors. / Os objetivos deste trabalho foram verificar a influência da cor do pelame na tolerância ao calor, consumo a pasto e ganho de peso de ovinos da raça Santa Inês de três diferentes cores de pelame (branca, castanha e preta). O experimento foi conduzido de janeiro a março de 2008 na Fazenda Riachão, localizada no município de Sairé, região agreste de Pernambuco. Os parâmetros fisiológicos temperatura retal (TR), frequência respiratória (FR), temperatura de pele (TPL) e temperatura da superfície do pelame (TSP), foram avaliados duas vezes por semana nos períodos da manhã e tarde durante oito semanas em esquema de parcela sub-subdividida. A taxa de sudação foi mensurada à tarde, uma vez a cada semana em esquema de parcela subdividida. O índice de tolerância ao calor dos animais foi avaliado uma vez por semana durante oito semanas com três tratamentos e sete repetições. Estimou-se o consumo a pasto e o ganho de peso foi avaliado por intermédio de pesagens semanais durante todo o período experimental. O ambiente foi monitorado diariamente por intermédio de uma estação meteorológica instalada ao lado do piquete experimental e índices de conforto foram calculados. O delineamento experimental nos três estudos foi inteiramente casualizado. Ovinos brancos apresentaram pequena superioridade na tolerância ao calor que os castanhos e pretos, mas isso não se refletiu no desempenho produtivo dos animais.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-26T11:26:40Z No. of bitstreams: 2 Dissertação - Thiago Nogueira Marins - 2016.pdf: 2347239 bytes, checksum: da0924ffa0d060e2454b33e1e8002115 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-26T11:27:18Z (GMT) No. of bitstreams: 2 Dissertação - Thiago Nogueira Marins - 2016.pdf: 2347239 bytes, checksum: da0924ffa0d060e2454b33e1e8002115 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-09-26T11:27:18Z (GMT). No. of bitstreams: 2 Dissertação - Thiago Nogueira Marins - 2016.pdf: 2347239 bytes, checksum: da0924ffa0d060e2454b33e1e8002115 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Heat stress is one of the most important factors with negative impact on the animal productivity in tropical countries. This longitudinal study was designed to describe the physiological response and the metabolic profile of Girolando (Holsteins X Gir, 3/4, 5/8 and 7/8) cows raised in a tropical region during the transition and voluntary waiting period (VWP). Twenty cows were selected using the following criteria: well distributed black and white coat, parity between two and seven, milk yeld between 18 and 22 L / day. The temperature-humidity index (THI) and black globe temperature and humidity index (BGT) of the micro environment were measured daily. Cows were clinically evaluated and submitted to blood collection in intervals distributed between three weeks before parturition until 60 days after calving (12 evaluations / cow). Physical examination included rectal temperature (RT), heart and respiratory rate (HR and RR) measured in the morning (6-8h) and afternoon (14-16h). RT and RR were used to calculate the Benezra Comfort Index (BCI). Metabolic profile was assessed by measurement of glucose, non-esterified fatty acid (NEFA), βhydroxybutyrate (βHBA), triglycerides, cholesterol, HDL, total serum protein, albumin, immune globulin, urea, creatinine, AST, GGT, calcium, phosphorus and magnesium. From 8-16h, throughout all the evaluation period, the average values of THI ranged from 73.5 and 78.7 and BGHI between 81.8 and 88.2. The variables HR, RR, RT and BCI differ (P <0.05) between morning and afternoon throughout the study period. Means glucose concentrations were similar in antepartum, decreased on the day of calving, reaching the lowest concentration on the 5th day postpartum. NEFA’s highest value was found on the day of parturition, and decreased, while βHBA decreased until the week before calving and increased on the calving day and after. The concentrations of triglycerides decreased, but cholesterol and HDL increased from the calving day. Total protein concentrations and immunoglobulin decreased from the second antepartum week and increased from the 2nd day postpartum. Urea increased on the week close to calving, but creatinine decreased postpartum. AST and GGT reached the highest value in the beginning of the postpartum period. Ca and P showed lower values on the calving day and Mg decreased during the early postpartum period, returning to the previous levels on the 10th day postpartum. In conclusion, thermal conditions and physiological differences during transition and VWP influence the evaluation of physical and metabolic variables. / O estresse térmico é um dos mais importantes fatores que influenciam negativamente a produtividade animal, em países de clima tropical. Esse estudo observacional longitudinal foi desenvolvido com o objetivo de descrever a resposta fisiológica e o perfil metabólico de vacas Girolando, criadas em região de clima tropical, durante os períodos de transição e espera voluntário. Foram avaliadas 20 vacas da raça Girolando, com grau de sangue 3/4, 5/8 e 7/8, pelagem preta e branca, entre duas e sete lactações e produção de 18 a 22 L/dia. O índice de temperatura e umidade (THI) e o índice de temperatura de globo e umidade (ITGU) do microclima da propriedade foram mensurados diariamente. As vacas foram avaliadas clinicamente e submetidas a colheita de sangue em intervalos de tempo distribuídos entre as três semanas antes do parto até o 60º dia pós-parto, perfazendo o total de 12 avaliações/vaca. Nos dias de avaliação, a Temperatura Retal, Frequência Cardíaca e Frequência Respiratória (TR, FC e FR) eram aferidas de manhã (6-8h) e a tarde (14-16h). A TR e FR foram utilizadas para cálculo do Índice de Conforto de Benezra (ICB) e o perfil metabólico foi avaliado pela mensuração das concentrações de glicose, ácido graxos não esterificado (AGNE), β hidroxibutirato (βHB), triglicerídeos, colesterol, HDL, proteína sérica total, albumina, imunoglobulina, ureia, creatinina, AST, GGT, cálcio, fósforo e magnésio. No período de 8 as 16h, durante todo o período de avaliação, os valores médios de THI variaram de 73,5 e 78,7 e de ITGU entre 81,8 e 88,2. As variáveis FC, FR e TR, e o ICB diferiram (P < 0,05) entre manhã e tarde, durante todo o período de estudo. As concentrações médias de glicose foram semelhantes no pré-parto, com queda no dia do parto e menor concentração no 5° dia pós-parto. Para AGNE o maior valor foi verificado no dia do parto, com posterior decréscimo, enquanto o βHB decresceu até a semana anterior ao parto e aumentou tanto no dia do parto quanto após. A partir do dia do parto, a concentração de triglicerídeos decresceu, mas as de colesterol e HDL aumentaram. As concentrações de proteína total e imunoglobulina caíram a partir da segunda semana pré-parto e aumentaram a partir do 2º dia pós-parto. A ureia aumentou com a proximidade do parto, e a creatinina houve decréscimo no pós-parto. O AST e GGT tiveram maiores concentrações no período pós-parto. O Ca e P tiveram menores valores no dia do parto; para Mg verificou-se queda no pós-parto imediato com retorno das concentrações anteriores no 10º dia pósparto. Portanto, conclui-se que os índices térmicos e o período fisiológico influenciam na avaliação das variáveis físicas e metabólicas.

Orientador: Maria Isabel Rodrigues / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-12T12:57:26Z (GMT). No. of bitstreams: 1 Colla_Eliane_D.pdf: 1516516 bytes, checksum: 2ea39d8d8dd66d24b6ec65db5dedeea9 (MD5) Previous issue date: 2008 / Resumo: A trealose é um agente natural de proteção em células de leveduras, fungos, bactérias, insetos e plantas, tendo sido indicada como componente essencial para a manutenção da viabilidade celular sob condições de estresse. Em função das diversas possibilidades de aplicação, especialmente em produtos de alto valor agregado como cosméticos e produtos farmacêuticos, onde pode exercer a função de estabilização e de proteção, a produção da trealose tem motivado inúmeras pesquisas. O objetivo principal deste trabalho foi selecionar leveduras potencialmente produtoras de trealose e otimizar as condições de produção utilizando meios de cultivo alternativos para a redução dos custos do processo. A primeira etapa consistiu na seleção de leveduras potencialmente produtoras de trealose, na qual foram testadas cepas isoladas de flores e frutos coletados no Cerrado (GO), Pantanal (MS), Floresta Amazônica (AM) e Mata Atlântica (SP), e também cepas isoladas de dornas de fermentação alcoólica de usinas produtoras de etanol do estado de São Paulo. A partir da gama de leveduras testadas, foram selecionadas duas cepas potencialmente produtoras de trealose, identificadas como Rhodotorula dairenensis e Rhodosporidium paludigenum, ambas isoladas de flores coletadas no bioma Cerrado. Na segunda etapa do estudo foi realizada a otimização do crescimento celular das leveduras citadas, uma vez que a trealose é um produto intracelular. Utilizou-se uma estratégia seqüencial de planejamento experimental, onde inicialmente foram avaliados os efeitos das concentrações de melaço, água de maceração de milho e extrato de levedura comercial Prodex Lac®, pH e temperatura de cultivo, sobre o crescimento celular de ambas leveduras, através de um planejamento fracionário. Posteriormente, um Delineamento Composto Central Rotacional (DCCR) foi utilizado para a otimização das condições de crescimento celular. Para a levedura Rhodotorula dairenensis estas condições corresponderam a 50g/L de melaço e 50g/L de água de maceração de milho, temperatura de cultivo de 30ºC e pH inicial de 5,5, obtendo-se resultados de massa seca de aproximadamente 19 g/L. Para Rhodosporidium paludigenum a massa seca atingiu 31 g/L em meio de cultivo contendo 50 g/L de melaço e 140 g/L de água de maceração de milho, a 25ºC e pH inicial de 5,5. Nestas condições, realizou-se o estudo da produção da trealose sob condições de estresse térmico onde as variáveis estudadas foram a temperatura (33-47ºC) e o tempo de exposição (60-120 minutos) dos cultivos ao estresse térmico, pela técnica de DCCR. Ambas cepas estudadas foram negativamente afetadas pelo acréscimo da temperatura de estresse térmico dentro da faixa estudada. Em temperaturas superiores a 40ºC houve diminuição do crescimento celular e viabilidade celular e, conseqüentemente, dos resultados de trealose. Para a levedura Rhodotorula dairenensis, o máximo rendimento de trealose intracelular obtido foi de aproximadamente 18% (g trealose/100g massa seca) em condições de temperatura de 34 a 35ºC e 70 - 90 minutos para o tempo de exposição ao estresse térmico. A cepa Rhodosporidium paludigenum apresentou rendimentos de aproximadamente 14 a 16% (g trealose/100g massa seca) na faixa de temperatura entre 35 e 40ºC, em qualquer tempo de exposição na faixa estudada (60 - 120 minutos) / Abstract: Trehalose is a natural cell-protecting agent that has been isolated and characterized from a large variety of plants, insects, fungi and bacteria, and many studies indicate that this disaccharide is an essential component for maintaining cell viability under stress conditions. Due to the potential application of trehalose, especially in cosmetics and pharmaceuticals fields, the interest of many research groups into the development of economically feasible production systems has increased in recent years. The present study reports on the screening for high trehalose production by yeasts and the optimization of the conditions for trehalose production using an industrial medium composed by molasses and corn steep liquor, to reduce costs of the cultivation medium. Initially, a technical screening was applied to select yeasts with a potential for trehalose production; strains isolated from pollen of flowers and fruits collected in different microhabitats in Brazil, and from alcoholic fermentation tanks were tested. Two potentially producing strains were selected and identified as Rhodotorula dairenensis and Rhodosporidium paludigenum, both isolated from flowers collected in Cerrado. Sequentially, a study for the cell growth optimization of the selected yeasts was performed, since trehalose is an intracellular product. A sequential strategy of experimental design was used; initially, the effects of the concentrations of sugar cane molasses, corn steep liquor and a commercial yeast extract Prodex Lac SD®, and of pH and temperature on the biomass were studied using a fractional design, which was followed by a central composite rotatable design (CCRD). For the yeast Rhodotorula dairenensis, the optimum values for cell growth were 50 g/L for the molasses and corn steep liquor concentrations, initial pH of 5.5 and temperature of 30 ºC, with no yeast extract, reaching values around 19 g/L for biomass. For the yeast Rhodosporidium paludigenum, biomass concentration obtained was 31 g/L in cultivation medium containing 50 g/L of molasses and 140g/L of corn steep liquor, initial pH of 5.5 and temperature of 25 ºC, with no yeast extract. Under these conditions, the production of trehalose was studied using a CCRD to optimize the temperature (33 to 47 ºC) and exposition time (60 to 120 minutes) of the cultures to the thermal stress. For both strains studied, the variable temperature presented a negative effect on trehalose accumulation, in the range studied. In conditions of temperature above 40 ºC there was a decrease of the cell growth and cell viability and, consequently, a decrease of trehalose yields. For the yeast Rhodotorula dairenensis the maximum intracellular trehalose content reached was 18% (g trehalose/100g dry cell) at temperatures of 34 and 35 ºC and between 70 and 90 min of exposition time to the thermal stress. For the strain Rhodosporidium paludigenum the statistical methodology led to maximum contents of intracellular trehalose in the range of 14 -16% (g trehalose/100g dry cell) under thermal stress temperatures of 35 - 40 ºC in all exposition time to the thermal stress in the range studied / Doutorado / Doutor em Engenharia de Alimentos

Les inflorescences de riz sont sensibles au froid et à la chaleur ce qui se traduit par une stérilité des épillets à floraison. Ce n'est cependant pas directement la température de l'air qui est en cause mais la température des tissus à des stades de développement précis. Les stratégies pour faire face au stress thermique sont : 1) la tolérance physiologique d'une variété particulière; 2) l'échappement temporel au stress par l'ajustement de la phénologie et de l'heure de l'anthèse (TOA); 3) l'évitement du stress par le microclimat généré par la culture. Cette thèse a pour but de caractériser l'effet des composantes climatiques sur 2) et 3), et pour ce, le même essai a été mené au champ sur quatre variétés de riz irrigué cultivées dans quatre environnements climatiques contrastés (Philippines, 2 saisons aux Sénégal, France). Bien que peu de différences variétales aient été observées au sein de chaque site, il existe une grande variabilité de l'heure de l'anthèse et de la différence de température (TD) entre panicule (Tp) et air (Tair) en réponse à l'environnement. La durée de l'anthèse est stable et limitée à environ 2 heures par jour, alors que l'heure de l'anthèse varie de 3.4 à 6.75 heure solaire. Au moment de l'anthèse, TD observée varie entre +2 et -9.5°C. TOA et TD sont principalement caractérisés par Tair et VPD (Vapour Pressure Deficit) observés antérieurement (TOA) ou pendant (TD) l'anthèse. De plus, il existe une corrélation significative entre la stérilité (chaud ou froid) observée à maturité et Tp aux stades sensibles. Ces résultats montrent qu'en termes de risque de stérilité paniculaire pour le riz irrigué à floraison, un climat moyennement chaud et humide est plus dangereux qu'un climat très chaud mais sec car un fort VPD favorise la transpiration de la canopée et des panicules. TOA et TD ont ensuite été intégrés au modèle de culture RIDEV V.2 (qui prédit la stérilité) et les simulations de TD ont été comparées aux résultats d'un autre modèle de Tp (IM2PACT) développé indépendamment au Japon. Ces deux modèles s'avèrent robustes, et de futures collaborations mèneront à une validation complète de chaque modèle voire une intégration de ceux-ci à un nouvel outil en vues d'étudier l'impact des changements climatiques sur les cultures.Les résultats de cette étude permettront dans un futur proche 1) d'aider les sélectionneurs en apportant de nouveaux traits d'intérêts, et 2) de définir un zonage des territoires à haut risque de stress thermique pour le riz irrigué, pour des scénarios climatiques actuels et anticipés. Des études complémentaires seront nécessaires pour permettre l'application de cette approche aux systèmes non irrigués. / At the reproductive stage, rice spikelets are sensitive to cold and to heat which can lead to spikelet sterility. However, it is not the air temperature but the temperature of the sensitive organ itself during some specific sensitive stages that is involved. There are three different strategies to cope with thermal stress: 1) physiological tolerance of a particular variety; 2) temporal escape of the stress thanks to phenology and time of day of anthesis (TOA) adjustments; 3) stress avoidance through microclimate generated by crop architecture and transpiration. This PhD aims to characterize the effect of environment on 2) and 3) and to attain this goal, the same experiment was conducted with four rice varieties irrigated and grown in four different climatic environments (Philippines, Senegal two seasons, France). Even though few varietal differences were observed within a site, a great variability of TOA and difference of temperature (TD) between panicle (Tp) and air (Tair) exists in response to the environment. Anthesis duration is stable and limited to 2 hours per day, whereas time of onset of anthesis varied between 3.4 to 6.75 hours after sunrise. During anthesis, observed TD varied between +2.5 and -9.5°C. TOA and TD are mostly explained with Tair and VPD (Vapour Pressure Deficit) observed before (TOA) or during (TD) anthesis. A significant correlation between spikelet sterility (due to cold or heat) and Tp at sensitive stages was established across sites and varieties. Those results showed that for irrigated rice, humid and moderately hot environments are more subject to heat stress sterility than very hot but dry environments, because panicle and canopy transpiration are favored by high VPD. Ultimately, RIDEV V.2 crop model (predicting spikelet sterility) was developed to integrate the previous results and Tp simulations were compared to another Tp model (IM2PACT) simulations, developed independently with a different approach in Japan. Those two models are robust and future collaborations will lead to complete model validations and maybe integration in a new modeling tool to answer the need in evaluating the impact of different climate change scenarios and the adaptation of crop response to those changes.In a short term, the results of this study will enable to 1) help breeders providing them new interest traits for thermal tolerance, and 2) define geographic zoning for high heat stress risk for irrigated rice, for present and future climate change scenarios. Complementary studies are needed to apply this approach to non irrigated system.

Dans le contexte de réchauffement climatique, le maintien des rendements est un enjeu majeur pour la filière viticole. L'augmentation des températures impacte négativement certaines phases clés du développement reproducteur en induisant notamment des phénomènes de coulure ou de pertes précoces d'inflorescence. L'altération du bilan carboné pourrait être un facteur majeur des diminutions de rendements en réponse aux températures élevées et l'évaluation de cette hypothèse permettrait d'ajuster les pratiques pour limiter les effets du réchauffement climatique. Si l'implication du bilan de carbone chez les plantes annuelles semble être à la base des baisses de rendement observées ces dernières années, les choses sont beaucoup moins claires chez des pérennes comme la vigne du fait des très nombreux co-facteurs possible ainsi que de la difficulté à expérimenter dans des conditions totalement contrôlées. Afin de s'affranchir de ces contraintes, notre étude a été réalisée en conditions contrôlées sur la Microvigne, un mutant naturel insensible à l'acide gibberelique et un nouveau modèle d'étude pour la génétique et la physiologie de la vigne. Ce mutant présente un phénotype nain et une floraison et fructification continues le long de l'axe proleptique. L'approche utilisée dans cette étude a consisté à (i) développer un cadre d'analyse adapté à la Microvigne; (ii) décrire l'impact de l'élévation de la température, sur les développements végétatif et reproducteur de la vigne, et plus particulièrement l'avortement des stades précoces du développement reproducteur; (iii) caractériser les changements du bilan de carbone de la Microvigne induits par la contrainte thermique, et enfin (iv) évaluer l'implication potentielle du bilan de carbone dans les phénomènes d'avortement précoces en réponse au stress thermique. Ce travail a permis de mettre en évidence des phénomènes d'avortement complet d'inflorescences en réponse à l'élévation des températures. Par ailleurs, nous avons pu montrer un rôle du statut carboné dans ce phénomène, soit via les teneurs totales en carbohydrates, soit via l'état global des réserves à l'échelle de la plante. Ce travail montre les potentialités su modèle Microvigne et ouvre de nouvelles perspectives pour l'analyse des effets des contraintes abiotiques sur le développement végétatif et reproducteur de la vigne. / Global warming is likely to be a major issue for grapevine yield sustainability in the next years. A common hypothesis is that long-term elevated temperatures may cause the failure of key phases of reproductive development, through their negative impact on carbon balance. However, testing the specific role of plant carbon status on yield elaboration under elevated temperatures is difficult on perennial crops, such as grapevine, and when environment fluctuates. To overcome these difficulties, the present work was conducted under fully controlled environment using a natural, giberrelic acid insensitive mutant of grapevine called Microvine, as a new model for grapevine genetics and physiological studies. This mutant present a dwarf stature and lack of juvenile characteristics leading to the continuous flowering and fruiting even during the first year after sowing. The present study was aimed at (i) developing a framework of analysis for Microvine; (ii) describing vegetative and reproductive developments responses to temperature elevation at whole plant level, and more precisely on early reproductive development abortions; (iii) characterizing grapevine carbon balance responses to temperature; and finally (iv) evaluating carbon balance implication in temperature-dependent early reproductive development abortions. This work shows that complete inflorescence abortions observed in response to temperature were related to carbon status, either expressed though total carbohydrate, or through the level of reserves at the whole plant level. This study opens the way to use Microvine as model to address the impact of climate warming on grapevine vegetative and reproductive developments.

Les éléments génétiques transposables (ET) sont des séquences d’ADN capables de se déplacer dans tous lesgénomes sous certaines conditions. Les ET ont des structures et des modes de transposition qui lesdifférencient en plusieurs groupes. Les éléments de la famille mariner sont ubiquistes ; lorsqu’ils sont actifs, ilsproduisent une transposase qui coupe l’élément et l’insère dans un autre locus. Des fragments d’éléments detype mariner (MLE) ont été précédemment identifiés chez la diatomée marine Amphora acutiuscula et ils semblaientactifs en condition de stress thermiques. Les diatomées sont caractérisées par une paroi siliceuse ornementée et,dans le milieu marin, elles jouent un rôle primordial dans les chaînes alimentaires.Dans le présent travail, par des méthodes de biologie moléculaire et de bioinformatique, nous avons recherché et caractérisé des MLE complets, et précisé leur activité en conditions de chocs thermiques et métalliques (cuivre et zinc). L’analyse des séquences amplifiées a mis en évidence la présence de MLE particuliers chez cette diatomée qui code une transposase ayant une triade catalytique DD43D jamais décrite jusqu’à présent.L’analyse phylogénétique place les MLE de diatomées dans une sousfamille différente mais proche de celle desMLE de plantes. Parmi les nombreuses copies de MLEprésentes dans le génome d’A. acutiuscula, certaines sont exprimées lorsque la diatomée est placée pendant 2 à 5 heures à unetempérature inférieure à sa température de culture. Par contre, l’expression des MLE n’a pas été mise en évidence chez cette espèce soumise aux stress métalliques appliqués. / Transposable elements (TE) are DNA sequences able to move in all genomes depending on conditions. TE have different structures and transposition mechanisms. Tc1-mariner elements are ubiquist ; when they are active, they produce a transposase which cuts and inserts the element into another locus. Fragments of mariner-like elements (MLE) hadpreviously been identified in the marine diatom Amphora acutiuscula and they seemed active under thermal stress. Diatoms are characterized by a siliceous ornamented cell wall and, in the ocean, they play a major role in trophic networks.In this work, with biomolecular and bioinformatic methods, we have searched for and characterized full length MLE, and precised their activity under thermal and metal (copper and zinc) stresses. The analyse of the DNA sequences obtained highlighted that MLE in diatoms are particular and that they encode a transposase which has a DD43D catalytic triad neverso far depicted. The phylogenetic analyse arranged diatom MLE in a subfamily different and close to that of plant MLE. Among the numerous MLE copies present in the genome of A.acutiuscula, some were expressed when the microalga was put at a lower temperature than the culture temperature for 2 to 5 hours. Conversely, metal stresses we applied did notinduce MLE expression in this species.

O aquecimento global é uma realidade e seus efeitos são bastante estudados atualmente. No entanto, pouca atenção tem-se dado para as alterações que ocorrem com invertebrados marinhos em decorrência dessa alteração climática. Sabe-se que uma das alterações que ocorrem em consequência do aumento da temperatura da água do mar, é o aumento do aparecimento de doenças no ambiente marinho. Para tanto, é importante que se avalie sua resposta imune inata frente a esse fator estressor. Os ouriços-do-mar foram escolhidos como modelo por serem considerados bons biondicadores ambientais, além de serem filogeneticamente próximos aos cordados, partilhando com estes, amplo repertório de genes e receptores envolvidos no sistema imune inato. O presente trabalho avaliou a resposta imune inata de ouriços-do-mar antárticos (S. neumayeri) e tropicais (L. variegatus e E. lucunter) frente ao estresse térmico por diferentes temperaturas e períodos de exposição. No que se refere aos ouriços-do-mar tropicais, foram estudadas duas espécies, uma que habita regiões menos submetidas a variações de marés (L. variegatus) e outra constantemente exposta a variações de maré (E. lucunter). Constatou-se uma diferença entre a resposta ao estresse térmico nas três espécies estudadas. A espécie antártica demonstrou alterações mais significativas de aumento na porcentagem de esferulócitos vermelhos (EV) e da capacidade fagocítica no período agudo de exposição (24h) quando submetidos a temperaturas intermediárias. Por outro lado, a espécie tropical E. lucunter apresentou alteração somente na porcentagem de EV no período de exposição crônico (7 e 14 dias) a temperaturas altas, enquanto que L. variegatus apresentou alteração neste tipo celular em todas as temperaturas experimentais e períodos avaliados, além de uma importante redução da capacidade fagocítica nos mesmos períodos que foi diretamente proporcional ao aumento da temperatura. Buscando compreender tais diferenças entre animais que habitam uma mesma região, verificou-se que a espécie L. variegatus apresentou alteração na adesão e espraiamento celular, no citoesqueleto de actina dos amebócitos fagocíticos (AF), na migração celular sem adição de substância quimiotática e na resposta quimiotática frente a leveduras S. cerevisiae, além de diminuição do estresse oxidativo em elevadas temperaturas. Constatou-se também que os AF desta espécie apresentaram alterações morfométricas importantes, como diminuição na circunferência celular e alteração na área de espraiamento. Por outro lado, a espécie E. lucunter não apresentou alteração em nenhum parâmetro analisado. Conclui-se, assim, que o estresse térmico atua de maneiras diferentes em espécies polares e tropicais de ouriços-do-mar. No entanto, os mecanismos moleculares pelos quais a espécie E. lucunter apresenta maior termotolerância em comparação à espécie L. variegatus permanecem imcompreendidos e merecem ser estudados. / Global warming is a reality and its effects are widely studied today. However, little attention has been given to the changes that occur to marine invertebrates due to this climate change. It is known that one of the changes that occur as a result of the seawater temperature rise is the increased occurrence of diseases in the marine environment. Therefore, it is important to evaluate the innate immune response against this stressor. The sea urchins were chosen as a model for being considered good environmental bioindicators, and are phylogenetically close to chordates, sharing with them large repertoire of genes and receptors involved in the innate immune system. This study evaluated the innate immune response of Antarctic (S. neumayeri) and tropical (L. variegatus and E. lucunter) sea urchins against thermal stress by different temperatures and exposure periods. With regard to tropical sea urchins, two species, one that inhabits sites less subject to tidal variations (L. variegatus) and the other constantly exposed to tidal oscilations (E. lucunter) were studied. A difference between the response to thermal stress in the three species was observed. The Antarctic species showed more significant changes regarding increase of the percentage of red spherule cells and phagocytic capacity in acute exposure period (24 h) when subjected to mild temperatures. On the other hand, tropical species E. lucunter presented only change in the percentage of red spherule cells during chronic exposure (7 and 14 days) at extreme temperatures, while L. variegatus showed a change in this cell type in all experimental temperatures and exposure periods evaluated, as well as a significant reduction in phagocytic capacity in the same periods that was directly proportional to the temperature increase. Trying to understand the differences between animals that inhabit the same region , it was found that the species L. variegatus showed changes in cell adhesion and spreading, actin cytoskeleton of phagocytic amoebocytes, cell migration without the addition of chemotactic substance and chemotactic response against yeasts S. cerevisiae, besides a reduction of oxidative stress at elevated temperatures. It was also found that the phagocytic amoebocyte of this species showed significant morphological changes, such as reduction in cell circunference and change in the area of spreading. On the other hand, the species E. lucunter presented no change in any parameter analyzed. Thus, it is concluded that the thermal stress acts differently in polar and tropical species of sea urchins. However, the molecular mechanisms by which the species E. lucunter shows higher thermotolerance compared to the species L. variegatus remain obscure and deserve to be studied.

This thesis deals with automotive headlamps, focusing on layout of temparature field and its influence on thermal stress of used materials, describes their history, kinds and ongoing research. Thesis shortly describes light and its characteristics, heat and heat transfer and means of temperature measurement. Main part of the tesis is dedicated to measuring front headlamp serving as a fog light, concretely measuring temperature field and illuminance depending of ambient temperature. Thesis contains everything from the first preparations, creation of measuring circuit, programming of measuring to processing acquired data. Thesis also compares cooler used for cooling luxmeter sensor, the comparision is between measured values and created simulation.