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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Rôle des lymphocytes T régulateurs humains dans l'échappement de la maladie associée à l'infection par le virus de l'hépatite C / Role of human regulatory T lymphocytes in the escape of liver disease related to hepatits C viral infection

Ouaguia, Laurissa 16 October 2015 (has links)
L’hépatite C est une pathologie hépatique caractérisée par un risque élevé de chronicité. Notre équipe a montré l’implication des lymphocytes T régulateurs naturels (Treg) et induits (iTreg) dans l’aggravation de cette pathologie. Cependant, l’impact direct du VHC sur ces 2 populations reste mal connu. Notre hypothèse est que le VHC pourrait aggraver l’environnement immunosuppresseur (i) en potentialisant le phénotype des Treg, (ii) en augmentant leur activité suppressive, (iii) en favorisant leur recrutement intra-hépatique et (iv) en induisant l’émergence d’iTreg. Dans la première partie de ma thèse, j’ai pu mettre confirmer une augmentation de la prévalence intrahépatique des Treg et des iTreg, corrélée à la progression de l’hépatite C vers le carcinome hépatocellulaire, chez un patient chroniquement infecté et suivi pendant 18 ans.Dans une deuxième partie, j’ai pu montrer que le VHC était capable (i) d’internaliser les Treg humains, (ii) de potentialiser leur phénotype régulateur, (iii) d’accroitre leur fonction suppressive, (iv) d’induire leur prolifération et la sécrétion de nombreux facteurs proinflammatoires, pouvant favoriser la chronicité de la maladie. Nous avons également suggéré que le VHC pourrait favoriser le recrutement intrahépatique des Treg.Dans la troisième partie, j’ai montré que le VHC favorisait l’émergence des iTreg, capables de supprimer la prolifération des cellules immunitaires, à partir des Tconv.Ces travaux montrent pour la première fois que le VHC pourrait favoriser l’instauration d’un microenvironnement immunosuppresseur et pourrait ainsi contribuer à la progression de la pathologie et à son l’échappement au système immunitaire. / Hepatitis C is characterized by a high risk of chronicity. Our team described the involvement of natural and induced regulatory T lymphocytes (Treg and iTreg) in the worsening of the disease. However, the specific impact of HCV on these 2 regulatory populations remains unclear. Our hypothesis is that HCV worsens the immunosuppressive environment by (i) promoting intrahepatic recruitment of Treg, (ii) increasing their suppressive phenotype and activity, and (iii) inducing the emergence of iTreg.In the first part of my thesis, I showed an increased intrahepatic frequency of Treg and iTreg correlated to the worsening of hepatitis C into cancer in a patient.In the second part, I showed for the first time that HCV was able (i) to internalize human Treg, (ii) potentiate their regulatory phenotype, (iii) increase their suppressive function, (iv) stimulate their proliferation and (v) induce the secretion of proinflammatory factors that can promote disease chronicity. I also showed that HCV increases the intrahepatic recruitment of Treg.In the third part, I showed that HCV can promote the emergence of iTreg which can efficiently suppress the immune response.My findings suggest that HCV promotes the intrahepatic recruitment of Treg cells, increases their regulatory phenotype and potentiates their suppressive activity. Very interestingly, I’ve also showed that HCV uptakes may promote hepatic inflammation by Treg cells. Finally, HCV seems to favor the emergence of induced regulatory cells. Taken together, these results strongly suggest that HCV increases the hepatic immunosuppressive environment and this may explain, at least partly, how the HCV escapes from the immune response.
42

Assessment of the vermicomposting process applied to sewage sludge by monitoring of the compost quality and immune responses of three earthworm species : Eisenia fetida, Eisenia andrei and Dendrobaena veneta / Évaluation du processus de lombricompostage appliqué aux boues d'épuration par le suivi de la qualité du compost et les réponses immunitaires de trois espèces de vers de terre : Eisenia fetida, Eisenia andrei et Dendrobaena Veneta

Rorat, Agnieszka 08 December 2015 (has links)
Le vermicompostage est une éco-biotechnologie relativement nouvelle qui utilise des vers de terre comme bioréacteurs naturels dans un procéssus de décomposition de la matière organique. En Europe, on utilise trois espèces d’annélides oligochètes : Eisenia fetida, Eisenia andrei et Dendrobaena veneta. Compte tenu des directives de l’Union Européenne portant sur le traitement des déchets, les contenus en métaux lourds, en composés chimiques divers et en microorganismes pathogènes des boues d’épuration ne permettent pas leur valorisation directe en agriculture. La qualité du produit obtenu après vermicompostage peut être évaluée en utilisant des paramètres agronomiques, tandis que des paramètres immunitaires et de défense mesurés chez les vers permettent d’apprécier l’impact des contaminants sur ces organismes du sol. Les objectifs de ce travail étaient: 1) apprécier l'influence des vers de terre sur la qualité du produit final dans le processus de lombricompostage, 2) examiner les mécanismes moléculaires et immunologiques mis en œuvre chez les lombrics au cours du lombricompostage de boues d'épuration urbaines, 3) de développer le compostage combiné au processus de lombricompostage. Les vers de terre utilisés dans les travaux présentés ont été classés en trois espèces grâce à la technique de barcoding moléculaire. Les fluorophores sélectionnés ont été testés comme les biomarqueurs spécifiques à l’espèce. Le contenu en riboflavine, le nombre de coelomocytes (amébocytes/éléocytes) et le niveau d’expression de gènes sélectionnés ont été utilisés comme biomarqueurs de stress permettant la bio-oisurvéillance du processus. La technique appliquée a conduit à évaluer les possibilités de valorisation des boues d'épuration. / Vermicomposting is a relatively new eco-biotechnology using earthworms as natural bioreactors in the process of decomposition of organic matter. Eisenia andrei, Eisenia fetida and Dendrobaena veneta are detrivorous organisms that enhance the decomposition of complex organic compounds and influence circulation of organic matter. This eco-technique is a non-expensive method of biodegradation of organic wastes, inter alia sewage sludge. Due to the high content of various pollutants, including heavy metals, chemicals and pathogenic microorganisms, sewage sludge cannot be directly used in agriculture. The quality of the product can be assessed using agronomic parameters, while immune and defense parameters can be measured as stress biomarkers. Aims of this work were: 1) to determine the influence of earthworms on the quality of the product obtained in vermicomposting process, 2) to investigate the molecular and immunological mechanisms occurring in earthworms during vermicomposting of municipal sewage sludge, 3) to develop the combined composting – vermicomposting process. Earthworms were segragated into three separate groups basing on DNA barcoding and selected fluorophores were tested as non-invasively retrieved biomarkers allowing distinction between morphologically similar composting earthworm species. Riboflavin, coelomocytes (amoebocytes/eleocytes) composition and particular gene expression levels were selected as biomarkers of stress useful in biomonitoring of the vermicomposting process. Applied technique has led to assess the possibilities of valorization of sewage sludge.
43

Etude du potentiel de valorisation de la Bauxaline® en matériaux de construction et de dépollution / Study of the potential of Bauxaline for building materials and depollution

Scribot, Cyril 26 April 2017 (has links)
Les boues rouges sont des sous-produits industriels issus de l’extraction d’alumine à partir de minerais de bauxite via le procédé Bayer. Le traitement de ces boues par filtre presse permet de réduire leur teneur en eau et d’obtenir un produit pelletable dénommé Bauxaline par l’usine Alteo de Gardanne, le tonnage annuel est de 300 000 t/an. Plusieurs applications ont été envisagées pour ce sous-produit industriel: matériaux de terres cuites, coulis, granulats légers et médias filtrants de dépollution. L’incorporation de la Bauxaline dans les matériaux de terres cuites vise la fabrication de tuiles. Les essais réalisés à l’échelle du laboratoire ont permis de mettre en évidence que l’argile naturelle est substituable par de la Bauxaline à hauteur de 30%. Ce taux de substitution permet de répondre aux exigences mécaniques et environnementales, aux contraintes sanitaires liées à la radioactivité naturelle de la Bauxaline. Aussi, l’incorporation de Bauxaline apporte une valeur ajoutée aux matériaux de terres cuites en permettant d’obtenir une teinte intéressante pour un fabricant de tuiles souhaitant élargir sa gamme. L’étude de formulation de coulis auto-compactants et de granulats légers a permis de démontrer la faisabilité aux niveaux mécaniques et environnementaux de l’incorporation de la Bauxaline avec des taux de substitution significatifs. La filière dépollution est également une voie intéressante : les granulés formulés à partir de Bauxaline présentent une bonne réactivité vis-à-vis des ions phosphates. Economiquement, cette piste de valorisation est aussi prometteuse : la Bauxaline constitue un matériau peu onéreux en comparaison aux médias filtrants du marché. / Red mud is an industrial by-product from the extraction of alumina from bauxite ores via the Bayer process. The treatment of these sludges with a filter press makes it possible to reduce their water content and to obtain an excavable product called Bauxaline by the Alteo de Gardanne plant, the annual tonnage is 300 000 t / year. Several applications have been considered for this industrial by-product: ceramic materials, grout, lightweight aggregates and depollution filter media. The incorporation of Bauxaline into the ceramic materials is aimed at the manufacture of tiles. Tests carried out on the scale of the laboratory made it possible to demonstrate that the natural clay is substitutable by Bauxaline for 30%. This substitution rate makes it possible to meet the mechanical and environmental requirements and the health constraints linked to the natural radioactivity of Bauxaline. Also, the incorporation of Bauxaline adds value to the materials of ceramic by allowing to obtain an interesting shade for a manufacturer of tiles wishing to widen its range. The study of the formulation of self-compacting grouts and light aggregates made it possible to demonstrate the feasibility at mechanical and environmental levels of the incorporation of Bauxaline with significant substitution rates. The process of depollution is also an interesting way: the granules formulated from Bauxaline have a good reactivity with respect to the phosphate ions. Economically, this upgrade path is also promising: the Bauxaline is a low-cost material compared to the filter media on the market.
44

Contribution à la valorisation des sédiments de dragage portuaire : technique routière, béton et granulats artificiels / Contribution to the valorisation of harbour dredging sediments : road construction, concrete and artificial aggregates

Azrar, Hassane 04 December 2014 (has links)
Face aux problématiques de gestion des sédiments de dragage portuaire, aujourd'hui, il apparait nécessaire de trouver des solutions potentielles de valorisation permettant de répondre efficacement à ces problématiques. La valorisation en génie civil, des sédiments des port de Saint Louis et de Dunkerque, présente une solution alternative à la gestion de ces matériaux. les travaux menés dans le cadre de cette thèse se focalisent d'une part, sur la valorisation des sédiments de Saint louis en technique routière et d'autre part, sur la valorisation des sédiments de Dunkerque en béton ainsi qu'en granulats artificiels. Après la caractérisation physico-chimique, minéralogique et mécanique, l'impact environnemental des sédiments bruts du Port de Saint Louis et le potentiel d'utilisation de ces matériaux en technique routière sont évalués. L'étude de formulation de matériaux, pour une utilisation en couche de fondation, s'est fondé sur une méthode expérimentale de détermination de compacité maximale. les mélanges granulaires optimaux remplissent les conditions d'utilisation en couche de fondation sont ensuite évalué au travers d'essais de lixiviation. La partie béton concerne la formulation des bétons à base de sédiment. Après la caractérisation de ces matériaux, trois bétons ont fait l'objet d'une étude de durabilité face à l'attaque sulfatique externe associé à une caractérisation non destructive en vue d'étudier l'influence d'incorporation des sédiments sur les propriétés des bétons. La partie granulats artificiels présente d'étude de faisabilité de granulats à base de sédiments, l'assiette granulaire et la technique de big-bag sont les deux méthodes de confection utilisées. / In front of problems of management of harbour dredging sediment, today, it appears necessary to find potential solutions of valosisation allowing to answer effectively these problems. the valorisation in civil engineering, of not immergeables sediments of ports of Dunkirk and Saint Louis, presents an alternative solution to the management of these materials. the works undertaken within the framework of this thesis are focused on the one hand, on the valorisation of Saint Louis sediment in road construction, and the other hand on the valorisation of Dunkirk sediment in concrete as well as artificials agregates. After physicochimical characterisation, mineralogical and mechanical, environmental impact of raw sediment of Saint Louis harbour and the potential use of these materials in road constuction are evaluated. the study of formulation of materials, for use in layer fondation, was based on an experimental method of determination of maximum compactness. The optimal granular mixtures fulfilling the terms of a use in a layer fondation are the evaluated through leaching tests. The concrete party concerns the formulation of the concretes containing Dunkerk sediment. After the characterisation of these materials, three concretes were the object of a durability study vis-a-vis the external sulphate attack associated with a not destructive characterisation in order to study the influence of incorporation of sediment on properties of concretes. The artificial aggregates party presents the feasibility study of aggregates with sediment, the granular plate and the big-bag technique are two making method used.
45

Évaluer la performance du lombricompostage des boues d'épuration en fonction des caractéristiques physico-chimiques de la boue et des espèces de vers de terre / Evaluate the performance of vermicomposting of sewage sludge according to physico-chimical characteristics of sludge and earthworm species

Suleiman, Hanine 15 December 2014 (has links)
Les boues d’épuration des eaux usées, produites en grandes quantités partout dans le monde, sont riches en matière organique et leur utilisation en tant que conditionneur de sol présente un intérêt potentiel. Cependant, la présence de polluants et notamment de contaminants non biodégradables tels que des métaux (Éléments Traces Métalliques: ETMs) peut limiter leur utilisation en agriculture et constitue un défi pour la protection de l'environnement. Le lombricompostage, processus biologique dans lequel des vers de terre sont utilisés pour accélérer la dégradation des déchets organiques, peut être appliqué aux boues. Des travaux ont montré que les vers peuvent accumuler certains ETMs et modifier leur biodisponibilité dans le compost. L'objectif principal de cette thèse est d'évaluer le lombricompostage en tant que processus de valorisation des boues d'épuration urbaines. Après une analyse bibliographique, des expérimentations en conditions contrôlées ont été réalisées afin d’évaluer l'efficacité du lombricompostage appliqué à différents boues (profils de contamination différents) et en utilisant différentes espèces de vers. Le compostage des boues en présence d’autres déchets a également été analysée. La qualité agronomique du compost a été évaluée de même que les capacités de tolérance de 3 espèces de vers et leur aptitude à accumuler plusieurs ETMs. Le traitement par lombricompostage a permis une réduction considérable de la masse du mélange traité et a considérablement changé les teneurs métalliques dans le compost obtenu. Globalement, le produit final présente des paramètres agronomiques acceptables au regard des normes de qualité en vigueur en France et en Pologne. / Large sewage sludge quantities are produced in wastewater plants, worldwide. Sewage sludge is rich in organic matter and its use as soil conditioner might be of interest. However, pollutants and especially non-biodegradable contaminants such as metallic trace elements (MTEs) are present in sludge. This may prevent the use of sewage sludge in agriculture and constitutes a challenge for environmental protection. Vermicomposting is an eco-friendly process in which earthworms are used to accelerate the degradation of organic wastes. Moreover, earthworms have shown an ability to accumulate MTEs and change the bioavailability of MTEs in compost. The main aim of this thesis was to evaluate the vermicomposting process applied to urban sewage sludge. After a bibliographic synthesis, experiments in controlled conditions have been performed in order to assess the effectiveness of vermicomposting applied to different sewage sludge (exhibiting contrasted contamination levels) and using different earthworm species. The mixing of different sewage sludge with other organic wastes has also been analyzed. The capacity of earthworms to accumulate several metals and their resistance to different contamination levels were also examined. Compost agronomic quality was assessed as well as the tolerance capabilities of three earthworm species and their ability to accumulate several MTEs. Vermicomposting treatment led to a significant reduction of the treated mixture weight and has significantly changed the content of several metals in the final product. Overall, vermicomposts were acceptable according to agronomic parameters and to compost quality norms in France and in Poland.
46

A comparison of traditional 6th - 8th grade middle schools and k - 8th grade academies in the areas of student achievement and school climate

Foley-Demby, Nikki L. 13 November 2014 (has links)
Researchers differ in their views of the structure of traditional middle and high schools in public education on student performance. They question the effectiveness of school and age level configuration, and its comparability with the age-appropriate cognitive, social and emotional development needs of students. Some believe that eliminating the traditional break between elementary and middle schools would enhance students' overall learning opportunities, particularly for ethnic minority and economically disadvantaged students and reduce the current disparity in student performance between traditional middle schools and K-8 academies. This research is founded on a study of (a) curricular and co-curricular richness of the core program; and (b) the organizational elements of the elementary and intermediate school configurations. This mixed-methods investigation utilized both quantitative and qualitative methods to develop the data. The quantitative method incorporated a comparison of six schools that were once either K-5 elementary schools or 6-8 traditional middle schools but were later reconfigured to encompass all grade levels making them K-8 Academies. The quantitative method was used to evaluate the quality of (a) student performance in mathematics and language arts as determined by state assessments (b) the school climate as perceived by the teachers, parents and community members. Creswell (2005) noted that the combination of quantitative and qualitative data gathering, analysis, and interviews strengthens the understanding of the problem and related research findings. Many school districts with 6-8 traditional middle schools have experienced students not making adequate progress and are considering changing their grade structure to K-8. DeJong and Craig (2002) list the reasons for this conversion to cause fewer transitions for students, to keep students in neighborhood schools, to reduce transportation costs, to improve safety, and to accommodate declining enrollment. The researcher hopes that, along with other current research, this study may serve to compel more school districts to consider adopting alternative grade configurations when students are not making adequate progress in the traditional 6-8 grade configuration. / text
47

Modelagem espacial da evapotranspiração utilizando Modelo de Duas Fontes em ambiente SIG para florestas e cana-de-açúcar / Spatial modeling of evapotranspiration using Two Source Model on GIS for forests and sugarcane

Bosquilia, Raoni Wainer Duarte 29 August 2016 (has links)
O presente trabalho avaliou diferentes parâmetros espaciais e temporais da evapotranspiração real (ETr) para três coberturas vegetais diferentes (cana-de-açúcar, floresta plantada e mata nativa) utilizando o Modelo de Duas Fontes (TSM) em ambiente SIG. Para a utilização do referido modelo, foi realizada uma adaptação do TSM aos padrões brasileiros e uma validação da estimativa de ETr com dados de balanços de chuva-vazão obtidos à campo em três bacias representativas na região de Corumbataí/SP, para dois anos hidrológicos completos. Desenvolveu-se também uma nova metodologia de integralização dos dados de ETr horários em mensais e anuais. Posteriormente, obteve-se a ETr para dois anos de estudo para áreas com cana-de-açúcar, floresta plantada e mata nativa. Avaliou-se como a evapotranspiração variou temporalmente e espacialmente, com a utilização dos parâmetros: altitude, declividade, faces de exposição do terreno, tipos de solo e biomas. Temporalmente, analisando os resultados mensais, sazonais e anuais, a cana-de-açúcar consumiu menos água do que a floresta plantada e a mata nativa. Para a altitude, concluiu-se que, quanto maior a altitude, maior a ETr anual. Quanto à declividade do terreno, concluiu-se que, quanto maior a declividade, maior foi a ETr anual. Quanto às faces de exposição do terreno, a face plana foi a que apresentou menor ETr. Para a mata nativa, as faces não apresentaram diferença; já para a floresta plantada, as faces norte e oeste consumiram mais água, enquanto para a cana-de-açúcar os maiores valores de ETr ocorreram na face oeste. Para os solos, as três coberturas vegetais apresentaram maior ETr em solos diferentes; porém o Neossolo Litólico apresentou altos consumos de água comumente entre todas as coberturas. Por fim, para a cultura da cana-de-açúcar, não foram obtidas diferenças significativas na estimativa de ET real anual quando plantada em áreas de Cerrado ou Mata Atlântica. Já para floresta plantada e mata nativa, houve variações significativas no consumo de água dessas coberturas, em áreas com esses biomas. / This study evaluated different spatial and temporal parameters of actual evapotranspiration (ETr) for three different vegetation cover (sugarcane, planted forest and native forest) using the Two Source Model (TSM) in a GIS environment. For the use of this model, was made an adaptation of TSM to Brazilian standards patterns and was made a validation of the estimated ETr with a rain-flow balance data obtained on the field in three representative watersheds in the region of Corumbataí/SP, Brazil, for two full years hydrological. It was developed a new methodology to convert hourly ETr to monthly and annually data. Later, was obtained the ETr for two years of study to areas with sugarcane, planted and natural forests and was evaluated how this evapotranspiration behaved temporally and spatially, using the parameters: altitude, slope, exposure faces of the terrain, soil types and biomes. Temporally, analyzing the monthly, seasonal and annual results, the sugarcane consumed less water than the planted and natural forests. For altitude, it was found that the higher the altitude, the greater the annual ETr. For the slope aspect, it was concluded that the higher the slope, the greater the annual ETr. As for the land exposure faces, the flat face showed the lowest ETr. For the native forest, the faces showed no difference. For the planted forest, north and west sides consumed more water, while for sugarcane higher ETr values were on the west face. For soils, the three vegetation covers showed higher ETr in different soils, but the Neossolo Litólico showed high water consumption common for all. Finally, for the sugarcane, were not obtained significant differences for the annual actual ET when planted in areas of Cerrado and Atlantic Forest. As for planted and natural forests, there were significant variations in water consumption by these covers on the area of the studied biomes.
48

O polimorfismo –251 A/T na região promotora do gene da interleucina 8 e o risco de câncer gástrico: estudo caso-controle / The polymorphism -251 A/T in the promoter region of the interleukin 8 gene and the risk of gastric cancer: case-control study

Felipe, Aledson Vitor [UNIFESP] 28 April 2010 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-28 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Introdução: A infecção por Helicobacter pylori está associada ao câncer gástrico (CG) não localizado na região da cárdia, no entanto, apenas uma pequena proporção das pessoas infectadas desenvolvem esta neoplasia. Estudos sobre cepas específicas dessa bactéria demonstram que os fatores genéticos e ambientais estão associados a esta carcinogênese. A Interleucina-8 (IL-8) desempenha um papel importante na inflamação da mucosa do estômago após a infecção por H. pylori. Estudos têm demonstrado que o polimorfismo da IL-8 pode aumentar o risco de CG. Objetivo: Investigar a associação entre o polimorfismo da IL-8, infecção por H. pylori, hábitos de vida e risco de CG. Casuística e métodos: Estudo caso-controle feito em pacientes com CG não-cárdia em comparação com indivíduos saudáveis na proporção de 1:2, respectivamente. O DNA foi extraído de leucócitos, purificado e a análise do polimorfismo foi feita pela técnica de PCR-RFLP e visualizado por eletroforese em gel de agarose a 5%. Infecção por H. pylori foi investigada pelos níveis séricos de anticorpos anti-H.pylori. Aspectos ambientais como tabagismo, etilismo e dieta foram investigados por questionário. Resultados: Um total de 312 indivíduos foi estudado, sendo 208 controles e 104 pacientes com câncer. Não houve diferença significante entre sexo ou idade, entre o grupo controle e os pacientes com CG. A proporção de pacientes infectados pelo H. pylori foi semelhante (p=0,15) entre os grupos controle (53,8%) e caso (45,2%). Menor frequência do genótipo AA foi encontrada no grupo com câncer (p = 0,01), sem diferença entre os alelos A e T. O tabagismo (p=0,001), acentuada ingestão de gordura (p=0,003) e baixa ingestão de legumes (p=0,02), foram mais frequentes no grupo caso. A análise de regressão logística multivariada demonstrou maior risco de CG em indivíduos com o genótipo heterozigoto AT (OR: 2,28 95%IC 1,16-4,49; p=0,02) e consumo excessivo de gordura (OR: 1,77 95%IC 1,12-2,92; p=0,03). Fumantes e ex-fumantes também demonstraram maior risco de CG quando comparados ao grupo controle (OR: 1,89 95%IC 1,41-3,11; p=0,01). Conclusões: A presença do genótipo AT está associada à elevação do risco de CG em aproximadamente duas vezes. O percentual de pacientes com CG infectados pelo H. pylori, diagnosticado pelos níveis de anticorpos séricos, não foi diferente do grupo controle na população estudada. Não observamos correlação entre a frequência alélica e o risco de CG. Indivíduos que consomem gorduras em excesso, ex-fumantes e fumantes têm maior risco de CG. / Background: Helicobacter pylori infection is associated with gastric cancer (GC) non-cardia, however, only a small proportion of infected people develop this cancer. Studies on specific strains of bacteria showed that the genetic and environmental factors are associated with this carcinogenesis. Interleukin-8 (IL-8) plays an important role in inflammation of the stomach mucosa after infection with H. pylori. Studies have shown that the polymorphism of IL-8 may increase the risk of GC. Objective: To investigate the association between polymorphism of IL-8, infection with H. pylori, lifestyle and risk of GC. Patients and methods: Case-control study done in patients with non-cardia GC compared with healthy subjects in the ratio 1:2, respectively. DNA was extracted from white blood cells, purified and polymorphism analysis was performed by PCR-RFLP and visualized by agarose gel electrophoresis to 5%. Infection with H. pylori was investigated by serum antibodies to H. pylori. Environmental issues such as smoking, alcohol consumption and diet were investigated by questionnaire. Results: A total of 312 individuals was studied, and 208 controls and 104 cancer patients. No significant differences between sex or age between the control group and patients with CG. The proportion of patients infected by H. pylori was similar (p=0.15) between the control group (53.8%) and case (45.2%). Lower frequency of AA genotype was found in the cancer group (p=0.01), however, no difference between alleles A and T. Cigarette smoking (p=0.001), sharp intake of fat (p=0.003) and low intake of vegetables (p=0.02) were more frequent in case group. A multivariate logistic regression analysis demonstrated a higher risk of GC in subjects with the heterozygous genotype AT (OR: 2.28 95% IC 1,16-4,49, p=0.02) and excessive consumption of fat (OR: 1 77 95% CI 1,12-2,92, p = 0.03). Smokers and former smokers also showed increased risk of GC compared to the control group (OR: 1.89 95% CI 1,41-3,11, p=0.01). Conclusions: The presence of the AT genotype is associated with increased risk of GC in about two times. The percentage of patients with GC infected with H. pylori, diagnosed by serum antibody levels was not different from the control group in the population. No correlations between allele frequency and risk of GC. Individuals who consume too much fat, ex-smokers and smokers have a higher risk of GC. / FAPESP: 08/05763 / TEDE / BV UNIFESP: Teses e dissertações
49

Modelagem espacial da evapotranspiração utilizando Modelo de Duas Fontes em ambiente SIG para florestas e cana-de-açúcar / Spatial modeling of evapotranspiration using Two Source Model on GIS for forests and sugarcane

Raoni Wainer Duarte Bosquilia 29 August 2016 (has links)
O presente trabalho avaliou diferentes parâmetros espaciais e temporais da evapotranspiração real (ETr) para três coberturas vegetais diferentes (cana-de-açúcar, floresta plantada e mata nativa) utilizando o Modelo de Duas Fontes (TSM) em ambiente SIG. Para a utilização do referido modelo, foi realizada uma adaptação do TSM aos padrões brasileiros e uma validação da estimativa de ETr com dados de balanços de chuva-vazão obtidos à campo em três bacias representativas na região de Corumbataí/SP, para dois anos hidrológicos completos. Desenvolveu-se também uma nova metodologia de integralização dos dados de ETr horários em mensais e anuais. Posteriormente, obteve-se a ETr para dois anos de estudo para áreas com cana-de-açúcar, floresta plantada e mata nativa. Avaliou-se como a evapotranspiração variou temporalmente e espacialmente, com a utilização dos parâmetros: altitude, declividade, faces de exposição do terreno, tipos de solo e biomas. Temporalmente, analisando os resultados mensais, sazonais e anuais, a cana-de-açúcar consumiu menos água do que a floresta plantada e a mata nativa. Para a altitude, concluiu-se que, quanto maior a altitude, maior a ETr anual. Quanto à declividade do terreno, concluiu-se que, quanto maior a declividade, maior foi a ETr anual. Quanto às faces de exposição do terreno, a face plana foi a que apresentou menor ETr. Para a mata nativa, as faces não apresentaram diferença; já para a floresta plantada, as faces norte e oeste consumiram mais água, enquanto para a cana-de-açúcar os maiores valores de ETr ocorreram na face oeste. Para os solos, as três coberturas vegetais apresentaram maior ETr em solos diferentes; porém o Neossolo Litólico apresentou altos consumos de água comumente entre todas as coberturas. Por fim, para a cultura da cana-de-açúcar, não foram obtidas diferenças significativas na estimativa de ET real anual quando plantada em áreas de Cerrado ou Mata Atlântica. Já para floresta plantada e mata nativa, houve variações significativas no consumo de água dessas coberturas, em áreas com esses biomas. / This study evaluated different spatial and temporal parameters of actual evapotranspiration (ETr) for three different vegetation cover (sugarcane, planted forest and native forest) using the Two Source Model (TSM) in a GIS environment. For the use of this model, was made an adaptation of TSM to Brazilian standards patterns and was made a validation of the estimated ETr with a rain-flow balance data obtained on the field in three representative watersheds in the region of Corumbataí/SP, Brazil, for two full years hydrological. It was developed a new methodology to convert hourly ETr to monthly and annually data. Later, was obtained the ETr for two years of study to areas with sugarcane, planted and natural forests and was evaluated how this evapotranspiration behaved temporally and spatially, using the parameters: altitude, slope, exposure faces of the terrain, soil types and biomes. Temporally, analyzing the monthly, seasonal and annual results, the sugarcane consumed less water than the planted and natural forests. For altitude, it was found that the higher the altitude, the greater the annual ETr. For the slope aspect, it was concluded that the higher the slope, the greater the annual ETr. As for the land exposure faces, the flat face showed the lowest ETr. For the native forest, the faces showed no difference. For the planted forest, north and west sides consumed more water, while for sugarcane higher ETr values were on the west face. For soils, the three vegetation covers showed higher ETr in different soils, but the Neossolo Litólico showed high water consumption common for all. Finally, for the sugarcane, were not obtained significant differences for the annual actual ET when planted in areas of Cerrado and Atlantic Forest. As for planted and natural forests, there were significant variations in water consumption by these covers on the area of the studied biomes.
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Analyse des produits lourds du pétrole par spectroscopie infrarouge / Analysis of heavy oils products by infrared spectroscopy

Laxalde, Jérémy 16 January 2012 (has links)
L’objectif de cette thèse était le développement d’une analyse rapide pour la caractérisation des produits lourds du pétrole. Des modèles de prédiction de propriétés des produits lourds ont été développés à partir des spectroscopies moyen-infrarouge (MIR) et proche infrarouge (PIR). Ce travail a principalement porté sur l’optimisation des modèles prédictifs des teneurs en composés saturés, aromatiques, résines et asphaltènes (SARA). Une optimisation simultanée par algorithmes génétiques du choix des prétraitements des données spectrales et des variables à sélectionner a été évaluée. Cette approchea permis de conduire au meilleur pouvoir prédictif des modèles PIR et a montré le potentiel d’interprétation des variables sélectionnées. Une étude de comparaison des modèles développés séparémentà partir des spectres MIR et PIR a ensuite été réalisée. La spectroscopie PIR s’est révélée être globalement plus performante dans le cadre de notre application. Il a également été démontré que la fusion de données spectroscopiques pouvait améliorer la qualité des prédictions. Au vu des résultats, ilsemble nécessaire que les modèles développés séparément à partir de ces spectroscopies conduisent à des performances similaires pour espérer une amélioration lors de la fusion des données spectrales. Le potentiel de l’interprétation des techniques de régression multiblock a également été confirmé pour identifier les informations spectrales spécifiques contenues dans les spectres MIR et PIR. Enfin, les modèles de prédiction de la densité, des teneurs en SARA, en carbone Conradson, en hydrogène, en soufre et en azote ont été jugées satisfaisantes pour une utilisation au laboratoire. / The aim of this study is to develop an alternative analysis for the characterisation of heavy oil products. Predictive chemometric models have been developed by mid-infrared (MIR) and near infrared (NIR) spectroscopies. This work has principally concerned the predictive model optimisation of saturate, aromatic, resin and asphalten contents (SARA). A simultaneous optimisation procedure of spectral data pre-processing methods and variable selection by genetic algorithms was evaluated. This approach has permitted to lead to the best NIR predictions and to show the interpretation potentialof selected variables. A comparative study of MIR and NIR spectroscopies for the development of heavy oil property predictive model was also performed. Results have shown that NIR spectroscopy was globally better for our application. It has been shown that spectroscopic data fusion can improve predictive power of models. The obtained results have shown that it seems however necessary that both spectroscopy, considered separately, have to lead to similar predictive power to expect an predictive power improvement when combining MIR and NIR. The interpretation potential of multiblock has been confirmed for the identification of MIR and NIR specific information. Finally, models developed for the prediction of density, contents of SARA, Conradson carbon, hydrogen, sulphur and nitrogen were judged satisfactory for an application at laboratory.

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