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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.
171

Estudo comparativo da oxigenação de hidrocarbonetos com ferroclorinas e ferroporfirinas como catalisadores em meio homogêneo e heterogeneizados / Comparative study of hydrocarbon oxygenation with ironchlorins and ironporphyrins as catalysts in homogeneous and heterogeneizated systems

Minorin, Tatiana Stedile 07 March 2008 (has links)
Neste trabalho, foram estudadas a oxidação do cicloexano e a epoxidação do (Z)- cicloocteno com iodosilbenzeno (PhIO) e H2O2 como oxidantes, comparando as FeIIIclorinas pentafluorossubstituídas com as FeIIIporfirinas, [Fe(TFPCMG)]Cl, [Fe(TFPCMGCH3)]Cl2, [Fe(TFPP)]Cl e [Fe(TF4TMAPP)](CF3SO3)5 como catalisadores em meio homogêneo e suportadas via ligação iônica e/ou covalente em matrizes de sílica quimicamente modificada. No caso do substrato (Z)-cicloocteno, os metalocomplexos utilizados levaram a rendimentos elevados para formação do ciclooctenóxido, tanto em meio homogêneo quanto heterogêneo, quando PhIO foi utilizado como oxidante. A atividade catalítica foi mantida mesmo após três reciclagens sucessivas. Com o H2O2 como oxidante, os rendimentos foram menores exceto com o metanol, quando se observa um aumento nos rendimentos de epoxidação, porque favorece a formação do intermediário ativo FeIIIhidroperóxido. Já os sistemas heterogeneizados apresentam desempenho bastante inferior quando comparado aos catalisadores em solução. Os melhores rendimentos foram observados com DCE um solvente mais viscoso que aumenta o tempo de vida da gaiola do solvente favorecendo o processo biomimético. Os catalisadores imobilizados foram caracterizados por espectroscopias UV-Vis e de RPE. Estas técnicas deram informações do estado de oxidação e de spin do metal, bem como a geometria do macrociclo na superfície da matriz sólida. Os resultados catalíticos puderam ser explicados pela natureza dos grupos funcionais que ligam o metalocomplexo à sílica, bem como, pelas informações fornecidas pela técnica de RPE quanto ao estado de oxidação do ferro e à geometria dos metalocomplexos imobilizados, dando consistência aos mecanismos propostos nos processos de oxidação. / In this work, the cyclohexane oxidation and the (Z)-cyclooctene epoxidation with iodosylbenzene (PhIO) e H2O2 as oxidants were studied. A comparison between fluorinated FeIIIchlorins and FeIIIporphyrins, [Fe(TFPCMG)]Cl, [Fe(TFPCMGCH3)]Cl2, [Fe(TFPP)]Cl, [Fe(TF4TMAPP)](CF3SO3)5 as catalysts was made either in solution or supported in silica matrices via eletrostatic interaction and/or covalent bonds. In the case of (Z)-cyclooctene epoxidation by PhIO, all the studied metallocomplexes achieved high yields for the epoxide production in both homogeneous and heterogeneous systems. The catalytic activity was maintained even after three successive recyclings. On the other hand, when H2O2 was used as oxidant the yields were lower. Differently, raised yields of epoxidation were observed when using methanol as solvent due to favored formation of the active intermediate FeIIIhydroperoxide. The performance of the heterogeneous systems was significantly lower than that of the catalysts in solution. The best yields were observed with DCE, a viscous solvent that probably raises the shelf life of the solvent cage favoring the biomimetic process. The supported systems were characterized by EPR and UV-Vis spectroscopies. These techniques gave information about the oxidation state and the metal spin, as well as the macrocycle geometry on the solid matrix surface. The catalytic results were explained by the nature of the functional groups that bound the metallocomplex to the silica matrix. In addition, the information obtained by the EPR technique regarding the state of oxidation of iron and the geometry of the supported metallocomplexes gave consistence to the proposed mechanisms in the oxidation processes.
172

Características do desempenho no WISC-III em crianças com dislexia do desenvolvimento / Characteristics of the WISC-III performance in children with developmental dyslexia

Carvalho, Mariana Kisse Sato 22 March 2013 (has links)
Esta pesquisa teve como objetivo analisar e comparar o desempenho no WISC-III de crianças com dislexia do desenvolvimento com o de dois grupos controle, a fim de verificar a existência de características específicas no desempenho desta escala no grupo com dislexia. Ao todo foram 57 sujeitos, divididos entre o grupo dos disléxicos (n=20), o grupo controle 1 (GC1) formado por crianças sem queixa de dificuldade escolar da mesma idade cronológica e série dos disléxicos (n=21), e grupo controle 2 (GC2) formado por alunos do segundo ano do Ensino Fundamental, que ainda estavam no processo inicial de aprendizagem da leitura e da escrita (n=16). Os dados do grupo dos disléxicos foram coletados a partir dos registros da Clínica Psicológica da Universidade Estadual de Londrina, em que constava o diagnóstico de dislexia no período de 2006 a 2011. Para o delineamento dos grupos controle, levou-se em consideração também a escola em que os disléxicos estavam matriculados na época da avaliação (estadual, municipal e particular). Para análise estatística, foi utilizado o programa SPSS para Windows, sendo que a significância adotada foi menor que 0,05. Quanto aos resultados, o grupo dos disléxicos, quando comparado aos dois grupos controle, teve pior desempenho nas Escalas de Resistência à Distração e Velocidade de Processamento. Pesquisas mostram que os disléxicos geralmente apresentam baixo desempenho em alguns subtestes, descrito como perfil ACID. Nesta pesquisa, o grupo dos disléxicos teve desempenho menor que os dois grupos controle nos subtestes Dígitos, Código e Procurar Símbolos, mas este dado não foi encontrado no subteste Aritmética. O desempenho dos disléxicos também foi menor nos subtestes Informação e Semelhanças, mas apenas em comparação ao GC1, o que sugere que esse resultado seja devido à dificuldade escolar do disléxico vivenciada através dos anos. Comparando-se as escolas, os alunos da escola particular tiveram melhor desempenho no subteste Códigos e pior desempenho no subteste Armar Objetos apenas em relação aos alunos da escola estadual. Como o grupo da escola particular foi muito pequeno, acredita-se que isso seja uma variação referente a este grupo específico de alunos. Quanto à comparação entre os disléxicos do sexo feminino e masculino, e com e sem TDAH, não foram encontradas diferenças estatisticamente significativas no desempenho dos subtestes. Concluindo, os dados da pesquisa coincidem com algumas pesquisas feitas de que parece haver um perfil dos disléxicos, que possuem menor desempenho nos subtestes que avaliam atenção visual e memória de trabalho. Entretanto, ao contrário dessas pesquisas, acredita-se que o menor desempenho no subteste Informação não seja uma característica peculiar dos disléxicos, mas sim consequência de sua dificuldade escolar / This study aimed to analyze and compare the performance on WISC-III in children with developmental dyslexia with the two control groups in order to check for specific performance characteristics of this scale in the group with dyslexia. Altogether, there were 57 subjects, divided between the group of dyslexics (n = 20), the control group 1 (GC1) formed by children without school difficulties of the same chronological age and grade of dyslexics (n = 21) and control group 2 (CG2) formed by students of the second year of elementary school, that were still in the initial process of reading and writing (n= 16). Data from the group of dyslexics were collected from the records of the Psychological Clinic at the Universidade Estadual de Londrina, which appeared the diagnosis of dyslexia in the period from 2006 to 2011. For the design of the control groups, the school that dyslexics were enrolled at the time of assessment (state, municipal and private) was considered. Statistical analysis was performed using the SPSS program for Windows, and the significance adopted was less than 0.05. As for the results, the group of dyslexics when compared to control groups had lower performance in sub scales Freedom from Distractibility and Processing Speed. Research shows that dyslexics often have low performance on some subtests, described as ACID profile. In this study, the dyslexic group had lower performance than the two control groups on Digit Span, Coding and Symbol Search, but this finding was not found in the Arithmetic subtest. The performance of dyslexics was also lower in Information and Similarities subtests, but only compared to the GC1, suggesting that this result is due to the difficulty of dyslexic school experienced through the years. Comparing schools, students in private schools performed better on subtest Coding and poorer performance on subtest Object Assembly only in relation to students of state school. As the private school group was very small, it is believed that this is a variation regarding this particular group of students. Regarding the comparison between dyslexics female and male, and with and without ADHD, there were no statistically significant differences. In conclusion, the survey data coincide with some research done that there seems to be a profile of dyslexics, who have lower performance in the tests that assess visual attention and working memory. However, unlike these studies, it is believed that the lower performance in the Information subtest is not a peculiar characteristic of dyslexics, but a consequence of their school difficulties
173

III-Sb-based solar cells and their integration on Si / Cellules solaires à base d'antimoniures et leur intégration sur Si

Tournet, Julie 21 March 2019 (has links)
Les matériaux III-Sb ont prouvé leur potentiel pour la réalisation de composants opto-électroniques dans des domaines aussi variés que les télécommunications ou l'environnement. Cependant, ils restent une filière quasi-inexplorée pour les systèmes photovoltaïques classiques. Dans ce projet de recherche, nous voulons démontrer que les composants à base d'antimoniures sont des candidats prometteurs pour des cellules solaires à haute efficacité et bas coût. Leurs avantages sont multiples : non seulement offrent-ils un large panel d'alliages accordés en maille et des jonctions tunnel à basse résistivité, mais ils permettent aussi une croissance directe sur substrat de Si. Nous étudions donc les briques élémentaires d'une cellule solaire multi-jonction intégrée sur Si. Tout d'abord, nous développons la croissance et fabrication de cellules homo-épitaxiales en GaSb. Les caractéristiques tension-intensité (J-V) mesurées sont proches de l'état de l'art avec une efficacité sous un soleil de 5.9 %. Puis, nous intégrons une cellule à simple jonction GaSb sur un substrat de Si par épitaxie par jet moléculaire (EJM). Les analyses de diffraction X (DRX) et de microscopie à force atomique (AFM) montrent des propriétés de structure et morphologie proches de celles reportées pour des buffers métamorphiques similaires dans la littérature. Nous adaptons alors la configuration de la cellule pour éviter la haute densité de défauts à l'interface GaSb/Si. La cellule hétéro-épitaxiale a une efficacité réduite de 0.6 %. Ce résultat est néanmoins proche des dernières avancées sur les cellules GaSb sur GaAs, et ce, malgré un désaccord de maille plus important. Enfin, nous étudions l'épitaxie d'AlInAsSb. Cet alliage pourrait en théorie atteindre une grande gamme d'énergies de bande interdite tout en restant accordé sur GaSb. Néanmoins, il souffre d'une lacune de miscibilité importante, le rendant sujet à la ségrégation de phase. Il n'y a que peu de mentions de l'AlInAsSb dans la littérature, et toutes rapportent des conditions de croissance instables et des énergies de bande interdite plus basses qu'attendues. Nous réussissons à produire des couches de bonne qualité d'AlInAsSb dont la composition en Al varie de 0.25 à 0.75 et ne présentant aucun signe macroscopique de décomposition de phase. Toutefois, l'observation au microscope à transmission électronique (TEM) révèle des fluctuations de composition nanométriques. Les données de photoluminescence (PL) sont étudiées pour déterminer les propriétés électroniques de l'alliage. Les mesures d'efficacité quantique (QE) montrent que la sous-cellule du haut limite la performance de la cellule tandem. Des modélisations numériques des courbes J-V et QE sont utilisées pour identifier des pistes d'amélioration pour chaque brique élémentaire. / III-Sb materials have demonstrated their potential for multiple opto-electronic devices, with applications stretching from communications to environment. However, they remain an almost unexplored segment for classical photovoltaic systems. In this research, we intend to demonstrate that III-Sb-based devices are promising candidates for high-efficiency, low-cost solar cells. Their benefits are two-fold: not only do they offer a wide range of lattice-matched alloys and low-resistivity tunnel junctions, but they also enable direct growth on Si substrates. We thus investigate the building blocks of a GaSb-based multi-junction solar cell integrated onto Si. First, we develop the photovoltaic growth and processing by fabricating homo-epitaxial GaSb cells. Intensity-voltage (J-V) measurements approach the state of the art with 1-sun efficiency of 5.9%. Then, we integrate a GaSb single-junction cell on a Si substrate by molecular beam epitaxy (MBE). X-ray diffraction (XRD) and atomic force microscopy (AFM) analysis show structural and morphological properties close to the best reported in the literature for similar metamorphic buffers. We further adapt the cell configuration to circumvent the high defect density at the GaSb/Si interface. The heteroepitaxial cell results in a reduced efficiency of 0.6%. Nevertheless, this performance is close the most recent advancements on GaSb heteroepitaxial cells on GaAs, despite a much larger mismatch. Last, we investigate the epitaxy of AlInAsSb. This alloy could in theory reach the widest range of bandgap energies while being lattice-matched to GaSb. However, it presents a large miscibility gap, making it vulnerable to phase segregation. AlInAsSb only counts few experimental reports in the literature, all referring to unoptimized growth conditions and abnormally low bandgap energies. We successfully grow good-quality layers with Al composition x_{Al} ranging from 0.25 to 0.75, showing no macroscopic sign of decomposition. Yet, transmission electron microscopy (TEM) observations point to nanometric fluctuations of the quaternary composition. Photoluminescence (PL) data is studied to determine the alloy's electronic properties. We eventually propose and fabricate a tandem cell structure, resulting in 5.2% efficiency. Quantum Efficiency (QE) measurements reveal that the top subcell is limiting the tandem performance. Numerical fits to both J-V and QE data indicate improvement paths for each building block.
174

FORMAS REDUZIDAS DO WISC-III: CARACTERÍSTICAS PSICOMÉTRICAS DE QUATRO MODELOS / SHORT FORMS OF THE WISC-III: PSYCHOMETRIC CHARACTERISTICS OF FOUR MODELS

Vechia, Shana Gularte Della 18 February 2011 (has links)
Made available in DSpace on 2016-03-22T17:26:30Z (GMT). No. of bitstreams: 1 DissMestrado Shana.pdf: 338004 bytes, checksum: 8c419b368591b3616b89b27429a39387 (MD5) Previous issue date: 2011-02-18 / This study aim of this study was to verify the Short Form of Wechsler Intelligence Scale for Children third edition (WISC-III) most appropriate for use in the Brazilian context and to present the psychometric characteristics of four models with two, for and eight subtests. The test takes about 90 minutes of application, a long time considered for evaluation. Short Forms can reduce the time of application and interpretation of results, facilitating its use in contexts where the intelligence assessment is secondary or in cases of search. But they are not suitable for classification of intelligence, or clinical purposes. The study was based in the standardization sample to the Brazilian context (n = 801). The reliability coefficients ranged from 0.81 to 0.94 and the validity of 0.66 to 0.93. Such coefficients were significant and acceptable, suggesting that the four Short Forms can be used for a quick estimate of IQ Total / O objetivo deste estudo foi verificar qual a Forma Reduzida da Escala de Inteligência Wechsler para Crianças terceira edição (WISC-III) é mais adequada para a utilização no contexto brasileiro e apresentar as características psicométricas de quatro modelos com dois, quatro e oito subtestes. O teste leva em média 90 minutos de aplicação, um tempo considerado extenso para avaliação. As Formas Reduzidas podem diminuir o tempo de aplicação e interpretação dos resultados, facilitando sua utilização em contextos onde a avaliação da inteligência é secundária ou em casos de pesquisa. O estudo foi baseado na amostra de padronização do instrumento ao contexto brasileiro (n=801). Os coeficientes de fidedignidade variaram de 0,81 a 0,94 e os de validade corrigida de 0,66 a 0,93. Tais coeficientes foram significativos e aceitáveis, sugerindo que as quatro Formas Reduzidas podem ser utilizadas para uma estimativa rápida do QI Total. Contudo, dos modelos estudados, a FR4 formada por Completar Figuras, Informação, Cubos e Vocabulário é a mais indicada para a utilização em função dos índices de validade, fidedignidade e redução de tempo
175

Purification and refolding of a novel dipeptidyl peptidase III

Jansson, Lennie January 2019 (has links)
There is a continuous search for novel enzymes to complement the abilities of today’s commercially available enzyme and find tailor-fit alternatives to suit the diverse array of bio-based industries. One application could be to increase biogas yield by finding substrate degrading proteases that can be added to the anaerobic digestion process and survive degradation themselves. A novel enzyme identified as a hypothetical dipeptidyl peptidase III, a zinc dependent metallo-protease, was found by a metaproteogenomics approach to be produced by the microorganisms of a thermophilic biogas process. The aim of this study was to express and refold a recombinant variant of the novel DPP III to its active form after production in inclusion bodies in Escherichia Coli. Assaying of refolding conditions was performed by stepwise dialysis and drip dilution. Nine attempts were performed based on findings in literature, although no other variant of DPP III has earlier been successfully refolded from inclusion bodies. The study resulted in a limited set of conditions of temperature, volumes, metal ions, salts and other additives being tested in the refolding buffers. Enzyme refolding and activation was monitored by the hydrolysis of the DPP III fluorescent substrate Arg-Arg β-naphthylamide trihydrochloride, alongside with measurements of protein concentration and SDS-PAGE. The novel DPP III was successfully purified but no definite strategy of producing correctly folded protein was found.
176

Estudo potenciométrico sobre a formação de complexos no sistema ferro (III)/azoteto, em meio não totalmente aquoso / Potentiometric study on the complexes formation in the iron (III)/azide system, in non totally aqueous medium

Pimenta, Adriano Cesar 28 April 2006 (has links)
Neste trabalho, a complexação do sistema ferro-III/azoteto em meio áqüeo-orgânico foi estudada para avaliar a formação dessas espécies sob diferentes forças iônicas: 1,00; 2,00 e 3,00 mol L-1 e em presença de diferentes solventes: tetraidrofurano, acetona e p-dioxano (T = 20 °C). Além disso, em meio contendo tetraidrofurano, as constantes de formação condicionais (b) foram determinadas sob diferentes percentagens deste solvente: 20, 30 e 40 % (v/v). O método empregado na determinação de tais constantes baseia-se na competição entre o metal e o íon hidrogênio pelo azoteto, no sistema tampão formado entre o ligante e o ácido azotídrico (N3-/HN3). Os parâmetros necessários para o cálculo das constantes de formação foram obtidos potenciometricamente por meio de variações de pH, provocadas pela complexação após a introdução do metal à célula. Tais parâmetros foram tratados preliminarmente pelo método de Leden e, posteriormente, refinados com alguns programas computacionais visando à caracterização das espécies e a determinação dos valores das constantes de formação globais dos complexos coexistentes no sistema Fe (III)/N3-. Os resultados mostraram evidências de que até quatro espécies complexas estáveis: [Fe(N3)]2+, [Fe(N3)2]+, [Fe(N3)3] e [Fe(N3)4]- podem coexistir tanto em meio contendo acetona quanto naquele contendo p-dioxano. Porém, em meio contendo tetraidrofurano, somente as três primeiras espécies foram detectadas (evidenciadas). Isto indica que uma maior competição entre o solvente orgânico e o ligante azoteto, na esfera de coordenação do íon metálico, ocorre em meios contendo tetraidrofurano, nestas condições estudadas. Verificou-se ainda que tanto a percentagem de solvente orgânico quanto a força iônica do meio têm forte influência na formação dos complexos sucessivos investigados, sendo que os complexos de maior estabilidade foram obtidos em soluções contendo 40 % (v/v) de tetraidrofurano e força iônica de 1,00 mol L-1. Diante dos resultados obtidos, observa-se que o método competitivo adotado neste trabalho, usualmente empregado em estudos realizados em meio totalmente aquoso, também se mostrou apropriado para a determinação das constantes de formação nas condições experimentais investigadas (meios áqüeos-orgânicos). / In this work, the system the iron-III/azide in aqueous-organic media was studied in order to evaluate the formation of complexes under different conditions: ionic strengths in the range of 1.00 to 3.00 mol L-1 and effect of the presence of organic solvents (tetrahydrofuran, acetone and p-dioxan) at T = 20 °C. Besides, in medium containing tetrahydrofuran, the conditional formation constants (b) were determined under different proportions of this solvent (20-40 %, v/v). The method used in the determination of these constants is based on the competition between the metal and the hydrogen ion for the azide, in the buffered system formed between the ligand and the azotidric acid (N3-/HN3). The parameters for the determination of the formation constant of each complexe were obtained by potentiometric measurements, through changes on the solution pH, caused by complexation due the iron ions added into the cell. These parameters were initially analysed by using the Leden method and, subsequently, refined by computational simulation in order to characterize the different complexes in the Fe (III)/N3- system, as well as to determine the value for the global constant of formation for each coexistent species. The results showed the possible coexistence of following four stable complexes: [Fe(N3)]2+, [Fe(N3)2]+, [Fe(N3)3] e [Fe(N3)4]- in aqueous medium containing acetone or p-dioxan. However, in the presence of tetrahydrofuran, the [Fe(N3)4]- was not evidenced. This indicates that a larger competition between the molecules of this organic solvent and the azide ligand, into the coordination sphere of the metallic ion occurs under these experimental conditions. Besides, the organic solvent proportion and the experimental medium are important parameters affecting the formation of these complexes. It was observed that iron complexes with higher stability were produced in the presence of 40 % (v/v) tetrahydrofuran and 1.00 mol L-1 ionic strength. Before the obtained results, it is observed that the competitive method adopted in this work, usually employed in studies accomplished in totally aqueous medium, it was also shown appropriate for the determination of the formation constants in the experimental conditions (aqueous-organic media) investigated.
177

Avaliação dos efeitos da subfração Acetato de etila III de Vemonia scorpioides em modelo de melanoma murino in vivo e in vitro / Vernonia scorpioides ethyl acetate III subfraction effect evaluation in model of in vivo and in vitro murine melanoma

Carrenho, Luise Zozula Blind 18 September 2009 (has links)
Vernonia Scorpioides tem sido utilizada popularmente no Brasil para tratar problemas de pele e úlceras crônicas, como as úlceras de perna decorrentes de diabetes. No presente estudo foi investigado o efeito da subfração acetato de etila III obtida do extrato bruto das folhas de Vernonia scorpioides in vitro, onde células de melanoma murino B16F10 foram submetidas à tratamento com várias concentrações no período de 24, 48, 72 e 96 horas, com o propósito de analisar a citotoxicidade da subfração frente às células. Percebemos uma alta citotoxicidade da subfração matando as células nas concentrações acima de 5 μg/ml, as células que receberam o tratamento de 1 g/ml não sofreram morte celular total. A morte celular foi elucidada com laranja de acridina e brometo de etídio. Um estudo mais detalhado das células foi feito com microscopia eletrônica. No estudo in vivo foi investigada a ação da subfração acetato de etila III na concentração de 5mg/Kg em camundongos C57BL6 com o objetivo de verificar a ação da subfração, sete dias de tratamento após dez dias da inoculação, tratamento profilático em dose única no primeiro dia da inoculação e tratamento precoce após 48 horas da inoculação com intervalos de dois dias. Os animais receberam via subcutânea, na região lombar dorsal 1,5 x 105 células de melanoma B16F10. Percebemos que o local em que a subfração acetato de etila III consegue disseminar-se pela massa tumoral ocorre a morte do tumor, extensa área de necrose é observada, quanto mais cedo e precoce o tratamento melhor o comportamento da massa tumoral a subfração acetato de etila III, o único órgão que reage é o baço se apresenta muito reativo proporcionalmente ao tamanho do tumor, os demais órgão não apresentam lesões, a subfração não causou nefrocitotoxicidade e hepatotoxicidade aparente. / Vernonia scorpioides has been tradionally used in Brazil in order to treat skin disorders and chronic wounds, such as leg ulcers in result to diabetes. The present study investigated the ethyl acetate III subfraction effect obtained from fresh leaves of Vernonia scorpioides in vitro, where B16F10 murine melanoma cells were submitted to treatment with several concentrations during 24, 48, 72 and 96 hours, to analyze citotoxicity subfraction before the cells. A high citotoxicity level of subfraction could be noticed killing cells above 5 μg/ml concentration, the cells which received 1 g/ml treatment have not suffered total cellular death. This death was elucidated with acridine orange/ethidium bromide staining, a deeper study of the cells was performed with electron microscopy, the action of ethyl acetate III subfraction in the 5mg/Kg concentration in C57BL6 mice was investigated in the in vivo study so that it is possible to verify the action of the subfraction seven days of treatment after ten days of inoculation, single dose of prophylactic treatment on the first day of inoculation and precocious treatment after 48 hours of inoculation with 48-hour intervals. The animals received subcutaneously 1,5 x 105 B16F10 murine melanoma cells. Tumor death is noticeable in the area where the ethyl acetate III subfraction could disseminate inside, a comprehensive necrosed area was observed, the sooner and more precocious the treatment the better the tumor will react to the ethyl acetate III subfraction, the only organ that reacts is the spleen which presents itself very reactive to the size of the tumor, the other organs do not display wounds, the subfraction did not cause apparent nefrotoxicity and hepatoxicity.
178

Estudo de incorporações de impurezas doadoras em estruturas semicondutoras III-V crescidas por epitaxia por feixes moleculares. / Study of incorporations of donor impurities in III-V semiconductor structures grown by molecular beam epitaxy.

Notari, Airton Carlos 29 April 1993 (has links)
Amostras de Semicondutores III-V foram crescidas usando a técnica de Epitaxia por feixes Moleculares. As propriedades elétricas das estruturas de GaAs com dopagem planar com Silício foram investigadas, e também a saturação e a difusão do Silício nestas amostras. As propriedades ópticas e elétricas das estruturas dopadas planarmente com Selênio foram analisadas, usando as técnicas de Capacitância-voltagem e a de Tunelamento resonante. As propriedades elétricas dos poços quânticos a base de InGaAs/GaAs foram investigadas, em função da posição da impureza planarmente dopada com Silício. / III-V semiconductor samples were grown using the Molecular beam epitaxy technique, the electrical properties of the GaAs structures planar doped with silicon were investigated as well as the Silicon saturation and diffusion in these samles. The optcal and electrical properties of structures planar doped with Selenium were analyzed using the Capacitance Voltage and resonant Tunneling techniques. The electrical properties of InGaAs/ GaAs based quantum wells were investigated as a function of the planar doped with Silicon impurity position.
179

Intégration de matériaux III-V à base d’arséniures et d’antimoniures pour la réalisation de transistors TriGate et NW à haute mobilité / Integration of III-V materials with arsenides and antimonides for the production of TriGate transistors and high mobility NWFET

Cerba, Tiphaine 24 October 2018 (has links)
La miniaturisation des transistors a progressé par noeud technologique avec l’introduction successive de nouveaux matériaux (high k) et de nouvelles architectures (FinFET, NWFET). Pour les noeuds technologiques avancés, une nouvelle rupture en matériau est envisagée pour remplacer le Silicium du canal de conduction par des matériaux à forte mobilité (2D, III-V). Les matériaux III-V sont de bons candidats pour répondre à cette problématique grâce à leur forte mobilité de type n (InGaAs, InAs, InSb) ou de type p (GaSb). Au cours de cette thèse, un intérêt particulier a été porté au couple de matériaux InAs/GaSb, qui offre un avantagesupplémentaire de par son accord de paramètre de maille permettant d’accéder dans une même structure à des couches de mobilités n et p. La croissance de matériau III-V directement sur substrat (001)-Si 300mm est aujourd’hui un challenge d’intérêt majeur pour proposer des procédés compatibles avec les plateformes industriels CMOS. Ces croissances restent complexes à cause de la formation de défauts : parois d’antiphase, dislocations, fissures ; générées respectivement par la différence depolarité, de paramètre de maille et de coefficient d’expansion thermique, entre le Silicium et les matériaux III-V. Dans cette thèse nous présentons une première démonstration de croissance par MOVPE de GaSb directement sur substrat (001)-Si nominal 300mm compatible avec les plateformes industrielles CMOS. Les couches de GaSb présentent une rugosité de surface sub-1nm, et une qualité cristalline au niveau de l’état de l’art en MBE. La croissance d’une couche d’InAs a ensuite permis la réalisation d’un démonstrateur FinFET à canaux multiples d’InAs. Ce derniera été élaboré via une technique lithographique alternative à haute résolution basée sur l’utilisation de copolymère à bloc. Ce procédé simple pour réaliser des canaux de conduction permet d’accéder à une forte densité de fils, de faibles dimensions, et en seulement cinq étapes de fabrication. / The transistors’s miniaturization evolved through technological nodes with the successive introduction of new materials (high k) and new architectures (FinFET, NWFET). For the advanced technological nodes, a new break in material is considered to replace the silicon of the conduction channel with high mobility materials (2D, III-V). III-V materials are good candidates to address a solution to this problem thanks to their n-type (InGaAs, InAs, InSb)or p-type (GaSb) high mobility. During this PhD, a particular interest has been given to the InAs/GaSb pair of materials, which offers an additional advantage by its lattice parameter agreement making it possible to access n-type and p-type high mobility layers in the same structure.Nowadays, the growth of III-V materials directly on (001) -Si 300mm substrates is a challenge of major interest to develop industrial platforms compatible processes. These growths remain complex because of defects formation: antiphase boundaries, dislocations, cracks; generated respectively by the difference in polarity, lattice mismatch and difference in thermal expansion coefficient, between the silicon and III-V materials. In this PhD, we present a first demonstration of GaSb growth by MOVPE directly on nominal (001) -Si 300mm substrate compatible with industrial platforms. The GaSb layers have a sub-1nm surface roughness, and an equal to MBE state of the art crystalline quality. The growth of a InAs layer then allowed the realization of an InAs FinFET multi-channel demonstrator. The latter was developed via a high resolution alternative lithographic technique based on the use of block copolymer. This simple method for producing conduction channels makes it possible to access a high density of wires, of small dimensions, and in only five manufacturingsteps.
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Avaliação da qualidade de vida em adultos com deformidade dentofacial de Classe III / Quality of life evaluation in adults with Class III dentofacial deformity

Valladares Neto, José 09 August 2013 (has links)
Objetivo: avaliar a qualidade de vida (QV) de adultos com deformidade dentofacial de Classe III e fatores associados. Material e Métodos: estudo caso-controle com 84 adultos-jovens, sendo 42 com deformidade dentofacial de Classe III e 42 com oclusão normal e face harmoniosa, pareados por frequência quanto à idade, sexo, cor da pele, índice de massa corporal e estado civil. A QV foi avaliada pela escala visual analógica (EVA) e pelos questionários SF-36, OHIP-14, PIDAQ e OQLQ. A complexidade da maloclusão foi determinada pelo índice de discrepância (DI) do Board Americano de Ortodontia e ângulo ANB. Resultados: a avaliação da consistência interna dos questionários foi boa / excelente (alfa de Cronbach entre 0,807 e 0,941) e da reprodutibilidade satisfatória [erro sistemático ausente (P = 0,4825, IC 95% = -4,54 a 2,31) e o erro casual, aceitável (Dalberg = 3,309)]. O SF-36 não mostrou diferença estatística entre os grupos (P = 0,2240), enquanto a EVA (P < 0,03), OHIP-14 (P < 0.0001), PIDAC (P < 0.0001) e OQLQ (P < 0.0001) mostraram diferença estatisticamente significante. Os domínios acompanharam a mesma tendência das escalas. A correlação mais forte entre os questionários ocorreu entre os de condição-específica: PIDAQ e OQLQ (P < 0,05, rs = 0,6683). Não houve correlação significativa do SF-36 com o OHIP-14, PIDAQ e OQLQ (P > 0.05), exceto com a EVA (P < 0,05, rs = 0,4677). O DI e o ângulo ANB tiveram correlação significativa e moderada entre si (P < 0,001, rs = -0,4677). A análise de regressão logística simples não mostrou associação entre o impacto da QV e fatores sociodemográficos, índice de massa corporal e a complexidade da maloclusão para o grupo caso. Conclusão: a deformidade dentofacial de Classe III apresentou impacto negativo da QV relacionada à saúde bucal e não foi identificado fator associado. As avaliações psicométrica e morfológica do paciente tendem a ser independentes entre si. / Aim: To assess quality of life (QoL) of adults with Class III dentofacial deformity and associated factors. Material and Methods: A case-control study with 84 young adults, 42 with Class III dentofacial deformity and 42 with normal occlusion and harmonious face matched for age, sex, color of skin, body mass index, and marital status. QoL was assessed by visual analog scale (VAS) and the SF-36, OHIP-14, and PIDAQ OQLQ questionnaires. The complexity of malocclusion was determined by the discrepancy index (DI) of the American Board of Orthodontics and ANB angle. Results: The internal consistency of the questionnaire was good/excellent (Cronbach\'s alpha between 0.807 and 0.941), and satisfactory reproducibility [systematic error absent (P = 0.4825, 95% CI = -4.54 to 2.31) and the acceptable random error (Dalberg = 3.309)]. The SF-36 showed no statistical difference between the groups (P = 0.2240), while the EVA (P < 0,03), OHIP-14 (P < 0.0001), PIDAC (P < 0.0001) and OQLQ (P < 0.0001) showed a statistically significant difference. The domains followed the same trend of the scales. The strongest correlation between the questionnaires occurred between condition-specific: PIDAQ and OQLQ (P < 0.05, rs = 0.6683). There was no significant correlation of the SF-36 with the OHIP-14, PIDAQ and OQLQ (P > 0.05), except with VAS (P < 0,05, rs = 0,4677). The DI and ANB had moderate and significant correlation between them (P < 0.001, rs = -0.4677). The analysis of simple logistic regression found no association between QOL and the impact of age, sex, color of skin, body mass index, marital status and complexity of malocclusion for the case group. Conclusion: Class III dentofacial deformity showed negative impact of oral health-related QoL and associated factor was not identified. The psychometric and morphological evaluation of the patient suggested independence between them.

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