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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.
151

Carcinomes rénaux : caractérisation moléculaire et des voies métaboliques dépendant des mécanismes hypoxiques / Renal cell carcinoma : molecular characterization and metabolic pathways dependent on hypoxic mechanisms

Ambrosetti, Damien 18 December 2015 (has links)
Les carcinomes rénaux (RCC) sont subdivisés en plusieurs sous-types, définis selon des critères histologiques, phénotypiques et génétiques. Le diagnostic différentiel de ces tumeurs est primordial avec des conséquences pronostiques et thérapeutiques. Génétique et diagnostic : Nous avons étudié les données cliniques, histologiques, immunohistochimiques et génétiques d'une série de RCC papillaires (PRCC) de type 1 et 2. Une caractérisation génomique exhaustive complétée par NGS nous a permis de classer les PRCC de type 2 dans plusieurs groupes d'évolution variable. Nos résultats fournissent des informations inédites sur la pathogenèse des PRCC qui donnent des pistes pour un traitement personnalisé. Métabolisme, grade tumoral et phénotype : Dans une série de RCC à cellules claires (ccRCC), nous avons analysé les caractéristiques de ces tumeurs et l'expression des protéines impliquées dans le métabolisme et les isoformes de HIF. Cette étude nous a permis de mettre en évidence quantitativement une corrélation entre l'expression de MCT1, GLUT1 et CAXII et le grade de Fuhrman, et qualitativement une localisation périphérique de HIF2alpha et la co-localisation des protéines HIF2alpha et HAF. Stratégies théranostiques : Dans l’optique de définir les traitements les plus appropriés pour les patients atteints de RCC, nous avons fait un parallèle entre la sensibilité aux thérapies ciblées des patients (in vivo) et de cellules dérivées de la tumeur initiale (in vitro). Nous avons démontré que la réponse chez les patients et dans les cellules était équivalente et donc que des tests in vitro sont une piste pour définir des traitements personnalisés des patients atteints de ccRCC. / Renal carcinomas (RCC) are divided into several subtypes, defined by histological, genetic and phenotypic criteria. The differential diagnosis of these tumors is important with prognostic and therapeutic implications. Genetics and diagnosis: We studied the clinical, histological, immunohistochemical and genetic of papillary RCC (PRCC) type 1 and 2 cohort. An extensive genomic characterization completed by NGS has allowed us to classify type 2 PRCC in several groups of variable clinical evolution. Our results provide new information on the pathogenesis of PRCC that provide perspectives for personalized treatment. Metabolism, tumor grade and phenotype: In a series of clear cell RCC (ccRCC), we analyzed the characteristics of these tumors and the expression of proteins involved in the metabolism and isoforms of HIF. This study allowed us to demonstrate quantitative correlation between the expression of MCT1, GLUT1 and CA XII and Fuhrman grade, and qualitatively peripheral HIF2alpha localization and co-localization of proteins HIF2alpha and HAF. Theranostic strategies: In order to define the most appropriate treatment for patients with RCC, we made a parallel between sensitivity to targeted therapies of patients (in vivo), and cells derived from the original tumor (in vitro). We have demonstrated that the response in patients and in cells and was similar, thus in vitro assays are a way to define personalized treatment for ccRCC.
152

Erfarenheter från insatserna i Somalia under 1990-talet : kopplat till utvecklingen av den amerikanska doktrinen FM3-24

Carlbaum, Gustaf January 2012 (has links)
Den amerikanska doktrinen FM3-24 beskriver hur en operation inom COIN-konceptet kan genomföras och hur befälhavaren kan använda doktrinen som stöd i genomförande och planering av operationer.  Doktrinen är utvecklad med stöd av de lärdomar som amerikanska trupper dragit i 2000-talets konflikter i Irak och Afghanistan, och doktrinen används idag som stöd i de pågående insatserna. Under 1990-talets konflikt i Somalia fanns inte denna doktrin.  Syftet med uppsatsen är att undersöka om det kan spåras lärdomar redan från 1990-talets Somalia till utformandet av den nu utvecklade amerikanska doktrinen FM3-24.  Resultatet visar att likheter finns i hur operationer enligt FM3-24 skall genomföras, dock är olikheterna de som är mest tydliga. Många av de steg som beskrivs i doktrinen har under insatsen avvikit helt eller vartefter insatsen fortskred. En orsak till det kan vara att amerikanska trupper under början av 1990-talet inte hade samma erfarenhet av COIN-insatser som de hade när doktrinen under 2000-talet utvecklades. I slutet av studien presenteras tänkta ”lessons learned” som kan vara bidragande till doktrinens utformning.
153

The effect of forest management and plant dominant on nitrogen transformation in soils of acidified mountain spruce forests in the Bohemian Forest National Park

STAŇKOVÁ, Pavla January 2013 (has links)
The aim of this study was to compare and contrast mineral and microbial nitrogen concentrations in soils of semi-natural and natural mountain spruce forests in the Březník area, the Bohemian Forest National Park, under dead wood and four plant dominants with respect to different forest management after windstorm and bark beetle events applied in 1997.
154

Identificação e caracterização de possiveis marcadores moleculares em carcinoma renal de células claras

Pires, Lilian Campos [UNESP] 19 February 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-19Bitstream added on 2014-06-13T19:53:57Z : No. of bitstreams: 1 pires_lc_me_sjrp.pdf: 2393717 bytes, checksum: a2b9ac8071136c02761c529a8ecaecef (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os dados de seqüência genômicas humanas depositados em bancos públicos têm fornecido uma oportunidade sem precedentes para pesquisadores decifrarem a funcionalidade do genoma humano. Essas informações são extremamente valiosas na prevenção, diagnóstico e tratamento do câncer. O Cancer Genome Anatomy Project (CGAP), o Gene Expression Omnibus (GEO), o Genome Data Mining (GDM) e o Babelomics funtional analysis of genome-scale experiments representam quatro importantes ferramentas para o estudo da genética funcional. O objetivo do presente trabalho foi o de explorar bancos de dados públicos para selecionar e validar a expressão de genes relacionados com o desenvolvimento e a progressão de carcinoma renal de células claras (CRcc). Utilizando ferramentas de bioinformática foi analisada a expressão gênica diferencial entre duas bibliotecas de SAGE elaboradas a partir de tecidos renais normais e de CRcc. Os resultados obtidos demonstraram alterações na expressão de genes participantes de importantes vias metabólicas. Baseando-se nessas análises, os genes CDK7, CLDN1, CSTB, EPC2 e ZNF706 foram selecionados e a expressão gênica diferencial desses foi avaliada por PCR em tempo real em 35 amostras de pacientes portadores de CRcc em diferentes estágios de progressão da doença e 1 amostra metastática. Paralelamente, utilizando-se a metodologia de RaSH foram elaboradas bibliotecas subtrativas entre o tecido neoplásico e o tecidos normal, sendo selecionados os genes MATR3 e PITPNB. O ZNF706 apresentou super expressão em relação aos tecidos normais, nas amostras tumorais analisadas independentemente do grau de evolução tumoral. O mesmo comportamento foi apresentado pelo gene CSTB, sendo que os maiores níveis de expressão foram observados nas amostras de estágio III de progressão tumoral. O gene CDK7 apresentou níveis de expressão dependente do grau de evolução da... / The data of human genomic sequences available in public database have provided an unpredictable opportunity for researchers to decipher the utility of human genome. This information is extremely valuable in prevention, diagnosis and cancer treatment. The Cancer Genome Anatomy Project (CGAP), the Gene expression Omnibus (GEO), the Genome Data Mining (GDM) and the Babelomics Functional Analysis of Genome-Scale Experiments do represent four important tools for functional genetics studies. This work aimed to explore public database to select and validate expression of genes related to development and progression of Clear Cell Renal Cell Carcinoma (ccRCC). The differential gene expression of two SAGE libraries from normal renal tissues and ccRCC was analyzed using bioinformatics tools. The results showed altered gene expression pattern in genes that participate in important metabolic pathways. Based on these analysis, the genes CDK7, CLDN1, CSTB, EPC2 and ZNF706 were selected and their differential gene expression was evaluated by Real Time PCR in 35 tissue samples from patients with ccRCC in different stages of disease progression and one metastatic sample. Simultaneously through RaSH methodology were elaborated subtractive libraries between normal and neoplasic tissues so the genes MATR3 and PITPNB were selected. The ZNF706 presented over expression in tumor tissues independent of tumor progression grade. The same behavior was presented by CSTB where the higher expression levels were observed in samples from stage IV of tumor progression. The CDK7 gene presented expression levels dependent of disease evolution grade where the lowers levels were in stages I, II, III and presented over expression in samples from stage IV and retroperitoneal metastasis. This result shows a clear relationship between CDK7 expression and the aggressiveness of ccRCC and suggests that this gene... (Complete abstract click electronic access below)
155

Avaliação de candidatos a marcadores moleculares envolvidos no carcinoma renal de células claras

Valsechi, Marina Curado [UNESP] 18 February 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-18Bitstream added on 2014-06-13T19:12:52Z : No. of bitstreams: 1 valsechi_mc_me_sjrp_parcial.pdf: 574533 bytes, checksum: a4733296b652ce8ac3b0aa3af78e4e48 (MD5) Bitstreams deleted on 2015-01-16T10:37:46Z: valsechi_mc_me_sjrp_parcial.pdf,Bitstream added on 2015-01-16T10:38:34Z : No. of bitstreams: 1 000590383.pdf: 1465270 bytes, checksum: 6abb1c740c0eb28b1d1eb0e5696f75a3 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O tumor renal é a mais letal das doenças urológicas. É uma doença histologicamente heterogênea, sendo o carcinoma renal de células claras o subtipo histológico mais comum. Embora a nefrectomia e imunoterapia sejam tratamentos bem estabelecidos, aproximadamente 30% dos pacientes tratados são acometidos por metástases. Alterações na expressão gênica e na inativação transcricional, devido ao mecanismo de metilação, são evidentes em células cancerosas. A metilação do DNA é um evento epigenético intimamente relacionado com o silenciamento da expressão gênica, e está envolvida em vários processos, dentre eles, a carcinogênese. Dessa forma, este trabalho teve como objetivos investigar se os genes selecionados, GPC3, CRABP2, KTN1 e ADAM23 apresentam expressão alterada nas amostras tumorais, verificar se a expressão gênica está associada com a progressão tumoral, e analisar o padrão de metilação de ilhas CpGs. Os quatro genes selecionados foram validados pela técnica de PCR em Tempo Real. Para validação desses genes foram utilizadas 35 amostras de carcinoma renal de células claras e 35 amostras de córtex renal normal. Os genes GPC3, CRABP2, KTN1 e ADAM23 apresentaram redução de expressão significativa em amostras de carcinoma renal de células claras quando comparadas ao pool de amostras de córtex renal normal. Observou-se que a redução da expressão do gene ADAM23 está diretamente relacionada com o avanço do estadiamento tumoral. Foi observada uma freqüência elevada de hipermetilação do gene ADAM23, entretanto, não houve associação do padrão de metilação com os dados clínicos. A análise da expressão gênica e dos mecanismos responsáveis pela inativação transcricional dos genes CRABP2, KTN1 e ADAM23, estudados pela primeira vez em carcinoma renal, e GPC3, podem fornecer informações relevantes para o conhecimento e desenvolvimento do carcinoma renal de células claras. / The renal tumor, which is the most lethal of urological diseases, is a histologically heterogeneous disease, and the clear cell renal cell carcinoma the most common histological subtype. Although the treatment of nephrectomy and immunotherapy are established, approximately 30% of patients are affected by metastases. Changes in gene expression and transcriptional inactivation, due to the methylation mechanism are evident in cancer cells. The DNA methylation is an epigenetic event closely related to the silencing of gene expression, and is involved in several cases, including the carcinogenesis. The aim of this study was to investigate the gene expression of GPC3, CRABP2, KTN1 and ADAM23, check if gene expression was associated with tumor progression and analyze methylation pattern of CpG island. The four selected genes were validated by the quantitative RT-PCR. Thirty five samples of clear cell renal cell carcinoma and 35 samples of normal renal cortex were used for validation. The genes GPC3, CRABP2, KTN1 and ADAM23 showed significant reduction of expression in samples of clear cell renal cell carcinoma when compared to a pool of samples of normal renal cortex. It was observed that the lower expression of ADAM23 is directly related to the advancement of the tumor staging. Despite the high frequency of hypermethylation of ADAM23, there was no association with the methylation pattern of the clinical data. The analysis of gene expression and the mechanisms responsible for the transcriptional inactivation of genes CRABP2, KTN1 and ADAM23, first studied in clear cell renal cell carcinoma, and GPC3, may provide relevant information for the clear cell renal cell carcinoma understanding and development.
156

Implication du facteur développemental Lim1, un nouvel oncogène, dans le cancer du rein humain avancé / Involvement of the developmental factor Lim1, a new oncogene, in advanced human kidney cancer

Hamaidi, Imene 26 September 2017 (has links)
Le carcinome à cellules rénales claires métastatique (CCC) demeure résistant aux thérapies actuelles. Les travaux précédents ont montré des similitudes mécanistiques entre tumorigenèse et néphrogenèse. Parmi les cibles de la voie oncogénique Sonic Hedgehog-Gli, le facteur développemental Lim1 a été identifié comme un nouvel oncogène dans le CCC. Les études préliminaires suggèrent que Lim1 aurait un rôle dans l’invasion cellulaire. Aucun inhibiteur de Lim1 n’est disponible; l’ARN interférence reste l’outil le plus efficace et le plus spécifique pour l’extinction des gènes. Dans le but de développer un nouvel outil d’inhibition de Lim1 applicable en clinique, basée sur des siRNAs véhiculés par des systèmes nanométriques, une nouvelle génération de véhicules de siRNAs a été étudiée. Il s’agit de polymères diacétyléniques photo-polymérisables sous forme de nanofibres (PDA-Nf). Ces travaux démontrent le rôle invasif de Lim1 dans la dissémination métastatique et identifient les PDA-Nf comme un nouvel outil de délivrance de siRNAs très prometteur en clinique. L’avantage du ciblage de Lim1 avec cette approche, est l’absence de son expression à l’âge adulte. / Clear cell renal cell carcinoma (CCC) remains resistant to current therapies, despite the development of anti-angiogenic and the new immunotherapeutic approaches. Previous work of the laboratory has shown mechanistic similarities between tumorigenesis and nephrogenesis. Among the targets of the Sonic Hedgehog-Gli pathway which is found oncogenic in CCC, the developmental factor Lim1 has been identified as a new oncogene in CCC. Preliminary studies suggest that Lim1 would have a role in cell invasion. No Lim1 inhibitors are available; RNA interference remains the most effective and specific tool for gene silencing. In order to develop a new clinically applicable inhibition tool for Lim1, based on siRNAs carried by nanoparticles, a new generation of siRNA vehicles has been investigated. These are photo-polymerizable diacetylenic polymers in the form of nanofibers (PDA-Nf). These works demonstrate the invasive role of Lim1 in metastatic dissemination and identifies PDA-Nf as a new promising siRNA delivery tool in clinical practice. The advantage of targeting Lim1 with this nano-carrier approach is that Lim1 is not expressed in adulthood.
157

Identificação e caracterização de possiveis marcadores moleculares em carcinoma renal de células claras /

Pires, Lilian Campos. January 2009 (has links)
Resumo: Os dados de seqüência genômicas humanas depositados em bancos públicos têm fornecido uma oportunidade sem precedentes para pesquisadores decifrarem a funcionalidade do genoma humano. Essas informações são extremamente valiosas na prevenção, diagnóstico e tratamento do câncer. O Cancer Genome Anatomy Project (CGAP), o Gene Expression Omnibus (GEO), o Genome Data Mining (GDM) e o Babelomics funtional analysis of genome-scale experiments representam quatro importantes ferramentas para o estudo da genética funcional. O objetivo do presente trabalho foi o de explorar bancos de dados públicos para selecionar e validar a expressão de genes relacionados com o desenvolvimento e a progressão de carcinoma renal de células claras (CRcc). Utilizando ferramentas de bioinformática foi analisada a expressão gênica diferencial entre duas bibliotecas de SAGE elaboradas a partir de tecidos renais normais e de CRcc. Os resultados obtidos demonstraram alterações na expressão de genes participantes de importantes vias metabólicas. Baseando-se nessas análises, os genes CDK7, CLDN1, CSTB, EPC2 e ZNF706 foram selecionados e a expressão gênica diferencial desses foi avaliada por PCR em tempo real em 35 amostras de pacientes portadores de CRcc em diferentes estágios de progressão da doença e 1 amostra metastática. Paralelamente, utilizando-se a metodologia de RaSH foram elaboradas bibliotecas subtrativas entre o tecido neoplásico e o tecidos normal, sendo selecionados os genes MATR3 e PITPNB. O ZNF706 apresentou super expressão em relação aos tecidos normais, nas amostras tumorais analisadas independentemente do grau de evolução tumoral. O mesmo comportamento foi apresentado pelo gene CSTB, sendo que os maiores níveis de expressão foram observados nas amostras de estágio III de progressão tumoral. O gene CDK7 apresentou níveis de expressão dependente do grau de evolução da... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The data of human genomic sequences available in public database have provided an unpredictable opportunity for researchers to decipher the utility of human genome. This information is extremely valuable in prevention, diagnosis and cancer treatment. The Cancer Genome Anatomy Project (CGAP), the Gene expression Omnibus (GEO), the Genome Data Mining (GDM) and the Babelomics Functional Analysis of Genome-Scale Experiments do represent four important tools for functional genetics studies. This work aimed to explore public database to select and validate expression of genes related to development and progression of Clear Cell Renal Cell Carcinoma (ccRCC). The differential gene expression of two SAGE libraries from normal renal tissues and ccRCC was analyzed using bioinformatics tools. The results showed altered gene expression pattern in genes that participate in important metabolic pathways. Based on these analysis, the genes CDK7, CLDN1, CSTB, EPC2 and ZNF706 were selected and their differential gene expression was evaluated by Real Time PCR in 35 tissue samples from patients with ccRCC in different stages of disease progression and one metastatic sample. Simultaneously through RaSH methodology were elaborated subtractive libraries between normal and neoplasic tissues so the genes MATR3 and PITPNB were selected. The ZNF706 presented over expression in tumor tissues independent of tumor progression grade. The same behavior was presented by CSTB where the higher expression levels were observed in samples from stage IV of tumor progression. The CDK7 gene presented expression levels dependent of disease evolution grade where the lowers levels were in stages I, II, III and presented over expression in samples from stage IV and retroperitoneal metastasis. This result shows a clear relationship between CDK7 expression and the aggressiveness of ccRCC and suggests that this gene... (Complete abstract click electronic access below) / Orientador: Paulo Peitl Junior / Coorientador: Paula Rahal / Banca: Raphael Bessa Parmagiani / Banca: Sônia Maria Oliani / Mestre
158

Avaliação da contaminação do sequenciamento do genoma mitocondrial por inserções nucleares de origem mitocondrial (NUMTs) no carcinoma renal de células claras / Evaluation of the mitochondrial genome sequencing contamination by nuclear inserts of mitochondrial origin (NUMTs) in clear cell renal carcinoma

Cláudia Tarcila Gomes Sares 09 March 2018 (has links)
O carcinoma renal de células claras é o tumor renal maligno mais frequentemente diagnosticado nos adultos. Uma série de defeitos genéticos tem sido observada no tecido tumoral renal e tais achados podem estar envolvidos na gênese ou progressão desses tumores. Alterações metabólicas e genéticas da mitocôndria são fatores que contribuem para muitas doenças humanas, incluindo o câncer. Objetivo: Estabelecer método para extração mitocondrial sem contaminação pelo DNA nuclear; verificar se existe contaminação por inserções nucleares de origem mitocondrial (NUMTs) no sequenciamento do genoma mitocondrial no carcinoma renal de células claras. Métodos: Para o estudo foram selecionados quatro pacientes portadores de carcinoma renal de células claras. Após a cirurgia obtivemos de cada paciente um fragmento de tumor e um fragmento de parênquima renal sem comprometimento neoplásico, as amostras de cada paciente foram extraídas de forma que ao final pudéssemos obter quatro amostras de DNA, sendo duas com isolamento da mitocôndria e duas sem o isolamento da mitocôndria. As amostras obtidas foram submetidas às seguintes análises genéticas: Sequenciamento completo do mtDNA; Reação em cadeia da polimerase para avaliação da contaminação do mtDNA obtido com isolamento da organela por DNA nuclear; avaliação do número de cópias do mtDNA (depleção) e patogenicidade das mutações. Resultados: Com os resultados obtidos neste estudo podemos afirmar que é possível a realização da extração do DNA mitocondrial sem a contaminação do genoma nuclear; e que o DNA mitocondrial extraído de maneira clássica do DNA total não apresentou contaminação por inserções nucleares de origem mitocondrial (NUMTs). / Clear cell renal carcinoma is the most frequently diagnosed malignant renal tumor in adults. A number of genetic defects have been observed in renal tumor tissue and such findings may be involved in the genesis or progression of these tumors. Metabolic and genetic changes in mitochondria are contributing factors to many human diseases, including cancer. Objective: To establish a method for mitochondrial extraction without nuclear DNA contamination; check for contamination by nuclear inserts of mitochondrial origin (NUMTs) in the sequencing of the mitochondrial genome in clear cell renal carcinoma. Methods: Four patients with clear cell renal carcinoma were selected for the study. After surgery, we obtained from each patient a tumor fragment and a renal parenchyma fragment without neoplastic involvement, the samples from each patient were extracted so that in the end we could obtain four DNA samples, two with mitochondrial isolation and two without the mitochondria isolation of mitochondria. The obtained samples were submitted to the following genetic analyzes: Complete sequencing of mtDNA; Polymerase chain reaction to evaluate the contamination of mtDNA obtained with organelle isolation by nuclear DNA; evaluation of mtDNA copy number (depletion) and pathogenicity of mutations. Results: With the results obtained in this study we can affirm that it is possible to perform mitochondrial DNA extraction without contamination of the nuclear genome; and that the mitochondrial DNA extracted from the classical DNA of the total DNA was not contaminated by nuclear inserts of mitochondrial origin (NUMTs).
159

Efeito de diferentes soluções na limpeza sônica dos precipitados do ácido fluorídrico sobre a resistência de união entre uma cerâmica feldspática e um cimento resinoso / Effect of different media ultrasonic cleaning of the hydrofluoric acid precipitates on the bond strength between a feldspatic ceramic and a resin cement

Martins, Maria Elizabeth Marques Nogueira 27 February 2009 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-05T17:34:01Z No. of bitstreams: 1 mariaelizabethmarquesnogueiramartins.pdf: 1395365 bytes, checksum: 31ef7ad43e8f7a11b3fd9d2120cbdddf (MD5) / Approved for entry into archive by Diamantino Mayra (mayra.diamantino@ufjf.edu.br) on 2016-10-06T12:30:28Z (GMT) No. of bitstreams: 1 mariaelizabethmarquesnogueiramartins.pdf: 1395365 bytes, checksum: 31ef7ad43e8f7a11b3fd9d2120cbdddf (MD5) / Made available in DSpace on 2016-10-06T12:30:28Z (GMT). No. of bitstreams: 1 mariaelizabethmarquesnogueiramartins.pdf: 1395365 bytes, checksum: 31ef7ad43e8f7a11b3fd9d2120cbdddf (MD5) Previous issue date: 2009-02-27 / O objetivo deste trabalho foi avaliar a hipótese: diferentes soluções utilizadas na limpeza sônica dos precipitados do ácido fluorídrico influenciam os valores de resistência de união entre uma cerâmica feldspática e um cimento resinoso. Foram confeccionados 20 blocos cerâmicos (VITA VM7®), os quais foram duplicados em resina composta (W3D®). Os blocos foram aleatoriamente divididos em quatro grupos (n = 5): G1 – AFL 9,6% (Dentsply®) por 20 segundos seguido pela lavagem jato ar-água (60 segundos) e secagem (Controle); G2 – AFL 9,6% por 20 segundos + limpeza sônica (Vitasonic®) com água destilada por 4 minutos e secagem; G3 – AFL 9,6% por 20 segundos + limpeza sônica com acetona 99,5% e secagem; G4 – AFL 9,6% por 20 segundos + limpeza sônica com álcool 70% por 4 minutos e secagem. Posteriormente, cada bloco cerâmico, foi silanizado Porcelain Primer (Dentsply®) e unido, com o cimento resinoso Rely XTM ARC, ao seu correspondente de resina composta. Cada conjunto cerâmica-cimento-resina composta foi seccionado no sentido X e Y, obtendo-se amostras (áreas reduzidas e padronizadas), com 1,0 mm2 de área adesiva. As amostras foram fixadas em um paquímetro adaptado, que foi acoplado em uma máquina de ensaios universal (EMIC) com célula de carga de 10 Kgf, velocidade de 1,0 mm/minuto e submetidos ao ensaio de tração. Os dados foram submetidos à análise de variância (ANOVA) e ao teste de Tukey com níveis de significância de 5%. Os valores de resistência de união e os desvios-padrão (MPa) para os grupos foram: G1) 16,60 ± 0,52a; G2) 18,75 ± 0,37b; G3) 16,09 ± 0,92a e; G4)15,75 ± 1,38a. A limpeza sônica póscondicionamento resultou em diferenças significantes (p < 0.05) entre os grupos. Com base nos resultados obtidos foi possível concluir que a limpeza sônica dos precipitados do ácido fluorídrico com água destilada, aumentou os valores de resistência de união. A limpeza sônica não alterou os valores de resistência de união quando se utilizou como solução acetona 99,5% e álcool 70%. / The objective of this study was to evaluate the hypotheses: different ultrasonic cleaning media of the hydrofluoric acid precipitates influence the values of union resistance between ceramic feldspatic and resinous cement. Twenty blocks of Vita VM7 ceramic (VITA ® ) were obtained. The cementation surface of each block was duplicated in resin composite (W3D ® ). Ceramic blocks were randomly assigned in to 4 groups (n = 5/per group): G1 – etching with 9,6% AFL (Dentsply ® ) for 20s + rinsing with water spray for 60s + drying (Control); G2 – 9,6% AFL for 20s + rinsing with water spray for 60s + ultrasonic cleaning (Vitasonic ® ) in distilled water for 4 min + drying; G3 – 9,6% HF for 20s + rising with water spray for 60s + ultrasonic cleaning in acetone 99,5% 4 min + drying; G4 – 9,6% AFL for 20s + rinsing with water spray for 60s + ultrasonic cleaning in alcohol 70% for 4 min + drying . The ceramic blocks were silanized Porcelain Primer (Dentsply ® ) and cemented to the composite blocks using the resin cement RelyXTM ARC. The cemented blocks were sectioned in to axes (X and Y) with a diamond disk under coolant irrigation in order to obtain microbars with 1,0 mm² of bonding area. Each bar was attached to an adapted device and the microtensile test was performed using a universal testing machine (crosshead speed: 1 mm/min. The bond strengths and SD in Mpa were as follows: G1) 16,60 ± 0,52a; G2) 18,75 ± 0,37b; G3) 16,09 ± 0,92a e; G4)15,75 ± 1,38a. Utrasonic cleaning media after etching resulted in signifant difference among the groups (p < 0,05) (One-way ANOVA and Tuckey test). Only ultrasonic cleaning in distilled water demonstrated the highest bon strength with the tested resin-cement to feldspatic ceramic. Ultrasonic cleaning in acetone 99,5% and alcohol 70% did not affect the bond results.
160

La nouvelle méthode Heliosat-4 pour l’évaluation du rayonnement solaire au sol / The new method Heliosat-4 for the assessment of surface solar radiation

Qu, Zhipeng 29 October 2013 (has links)
Plusieurs méthodes existent pour évaluer de manière opérationnelle l'éclairement solaire au sol à partir d'images acquises par satellite. Durant sa thèse soutenue en 2009 à MINES ParisTech, Oumbe a conçu une nouvelle méthode, Heliosat-4, faisant appel à des modèles numériques du transfert radiatif et à des approximations d'exécution rapide. La présente thèse vise à consolider ces résultats et à effectuer la validation complète de la méthode Heliosat-4. Elle s'inscrit dans une collaboration scientifique internationale dans les projets européens MACC (Monitoring Atmosphere Composition and Climate) et MACC-II.Oumbe a proposé une approximation de l'équation de transfert radiatif s'écrivant alors comme un produit de l'éclairement par ciel clair par un terme d'extinction dû aux nuages. Nous avons établi que les erreurs liées à cette approximation sont très faibles dans les conditions usuelles et qu'elle peut donc être utilisée dans Heliosat-4, ce qui en facilitera l'implémentation informatique ainsi que son fonctionnement opérationnelle.La méthode Heliosat-4 est donc ainsi composé de deux modèles composés d'abaques : McClear pour l'éclairement par ciel clair et McCloud pour l'extinction cet éclairement due aux nuages. A l'aide de mesures in-situ d'éclairements direct et diffus de référence, nous avons analysé finement les performances de Heliosat-4 selon différentes conditions. La qualité de la première version pré-opérationnelle de Heliosat-4 est jugée satisfaisante car elle permet des estimations d'éclairement global avec une précision de l'ordre de celles des méthodes existantes mais des estimations des composantes directe et diffuse sensiblement de meilleure qualité. / Several methods have been developed to assess operationally the surface solar irradiance from satellite images. During his PhD thesis presented in 2009 at MINES ParisTech, Oumbe has designed a new method using numerical radiative transfer model and fast approximations. The present PhD thesis aimed at consolidating these results and validating Heliosat-4. This work is the international scientific collaboration framework of the European-funded projects MACC (Monitoring Atmosphere Composition and Climate) and MACC-II.As a foundation of Heliosat-4, Oumbe has proposed an approximation of the radiative transfer equation by a product of clear-sky irradiance and a term describing the cloud extinction. We have established that estimation errors due to this approximation are very small in usual conditions and that this approximation may be adopted. It allows a convenient modular development of Heliosat-4 and eases its future operational use.The Heliosat-4 method is then composed of two abacus-based models: McClear for the irradiance under clear-sky and McCloud for the irradiance extinction due to clouds. With in-situ reference measurements of direct and diffuse irradiance, we have carried out deep performance analysis of Heliosat-4, under different conditions. The quality of this first preoperational version of Heliosat-4 is judged satisfactory as it enables estimations of global irradiance with the same level of quality of other existing methods in literature but also estimations of direct and diffuse irradiances with a noticeable better quality.

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