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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.
131

Mechanisms and pathways for proton transfer in cytochrome-c oxidase

Ädelroth, Pia. January 1998 (has links)
Thesis (doctoral)--Göteborg University, 1998. / Added t.p. with thesis statement inserted. Includes bibliographical references.
132

Wohnen mit Geschichte die Appartements Friedrich Wilhelms IV. von Preussen in historischen Residenzen der Hohenzollern

Meiner, Jörg January 2004 (has links)
Zugl.: Berlin, Humboldt-Univ., Diss., 2004
133

Structure-function relationships within cytochrome C oxidase and complex I a dissertation /

Lemma-Gray, Patrizia. January 2008 (has links)
Dissertation (Ph.D.) --University of Texas Graduate School of Biomedical Sciences at San Antonio, 2008. / Vita. Includes bibliographical references.
134

Diagnostic Utility of WISC-IV General Abilities Index and Cognitive Proficiency Index Difference Scores among Children with ADHD

January 2010 (has links)
abstract: The Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) General Abilities Index (GAI) and Cognitive Proficiency Index (CPI) have been advanced as possible diagnostic markers of Attention-Deficit Hyperactivity Disorder (ADHD). Diagnostic utility statistics were used to test the ability of GAI-CPI difference scores to identify children with ADHD. Participants included an ADHD sample (n = 78), a referred but non-diagnosed hospital sample (n = 66), and a simulated sample with virtually identical psychometric characteristics as the WISC-IV 2,200 child standardization sample. Receiver Operating Characteristic (ROC) analyses were computed to determine the utility of GAI-CPI difference scores to identify children with ADHD. The GAI-CPI discrepancy method had an AUC of .64, 95% CI [0.58, 0.71] for the ADHD sample compared to the simulated normative sample and an AUC of .46, 95% CI [0.37, 0.56] for the ADHD sample compared to the referred but non-diagnosed hospital sample. These AUC scores indicate that the GAI-CPI discrepancy method has low accuracy. / Dissertation/Thesis / M.A. Educational Psychology 2010
135

Factor Structure of the Wechsler Intelligence Scales for Children-Fourth Edition Among Referred Native American Students

January 2011 (has links)
abstract: The Native American population is severely underrepresented in empirical test validity research despite being overrepresented in special education programs and at an increased risk for special educational evaluation. This study is the first to investigate the structural validity of the Wechsler Intelligence Scale for Children - Fourth Edition (WISC-IV) with a Native American sample. The structural validity of the WISC-IV was investigated using the core subtest scores of 176, six-to-sixteen-year-old Native American children referred for a psychoeducational evaluation. The exploratory factor analysis procedures reported in the WISC-IV technical manual were replicated with the current sample. Congruence coefficients were used to measure the similarity between the derived factor structure and the normative factor structure. The Schmid-Leiman orthogonalization procedure was used to study the role of the higher-order general ability factor. Results support the structural validity of the first-order and higher-order factors of the WISC-IV within this sample. The normative first-order factor structure was replicated in this sample, and the Schmid-Leiman procedure identified a higher-order general ability factor that accounted for the greatest amount of common variance (70%) and total variance (37%). The results support the structural validity of the WISC-IV within a referred Native American sample. The outcome also suggests that interpretation of the WISC-IV scores should focus on the global ability factor. / Dissertation/Thesis / Ph.D. Educational Psychology 2011
136

Modernização, ordenamento do território e desigualdade socioespacial às margens do reservatório de Corumbá IV : a perspectiva das comunidades rurais tradicionais

Mejia, Lidia 11 1900 (has links)
Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Humanas, Departamento de Geografia, 2007. / Submitted by Luanna Maia (luanna@bce.unb.br) on 2009-03-06T15:24:37Z No. of bitstreams: 1 Dissertacao Lidia Mejia 29_11.pdf: 2383033 bytes, checksum: 83aa22d08d044ea08f2fe7d9ce6c354c (MD5) / Approved for entry into archive by Luanna Maia(luanna@bce.unb.br) on 2009-03-06T16:09:06Z (GMT) No. of bitstreams: 1 Dissertacao Lidia Mejia 29_11.pdf: 2383033 bytes, checksum: 83aa22d08d044ea08f2fe7d9ce6c354c (MD5) / Made available in DSpace on 2009-03-06T16:09:06Z (GMT). No. of bitstreams: 1 Dissertacao Lidia Mejia 29_11.pdf: 2383033 bytes, checksum: 83aa22d08d044ea08f2fe7d9ce6c354c (MD5) / A construção de barragens e usinas hidrelétricas auxilia o desenvolvimento econômico das nações há mais de um século. O controle e regularização de vazões, a irrigação, o abastecimento de água e a geração de energia elétrica estão entre os diversos usos de barragens. O desenvolvimento industrial foi implantado tardiamente no Brasil, provocando migrações e acelerando o crescimento urbano. Este fenômeno veio acompanhado, nas últimas décadas, de exigências do setor tecnológico agrícola. Um processo que tem gerado demandas cada vez maiores por abastecimento de água e energia. Com a finalidade de responder a esta crescente necessidade, em Goiás, estado localizado no centrooeste do País, foi construída a Usina Hidrelétrica de Corumbá IV. Trata-se de um dos grandes empreendimentos voltados para o desenvolvimento e a infraestrutura regional, sobretudo para o Distrito Federal, vizinho à região. Contudo, seu projeto, divulgado como inovador, tem causado polêmicas desde os primeiros passos da concessão. Por outro lado, a obra da usina e o armazenamento do reservatório têm provocado significativas alterações nos municípios de sua área de influência, em particular as comunidades rurais tradicionais. Assim, a dissertação tem por objetivo analisar os efeitos sócio-espaciais do reservatório hidrelétrico de Corumbá IV, dando ênfase ao ordenamento territorial dos municípios lindeiros. Achados indicam que há limitações e contradições inerentes ao ordenamento territorial e desenvolvimento sustentável que condicionam o alcance do acordo social que contemple a heterogeneidade dos usos dos recursos e dos territórios. Ao analisar a perspectiva da comunidade tradicional sobre o empreendimento, constatou-se com esta pesquisa, a persistência de um modelo de desenvolvimento cujas transformações econômicas não são acompanhadas de novas alternativas que possam representar uma melhoria na qualidade de vida com a inserção de comunidades tradicionais aos processos de produção contemporâneos. ___________________________________________________________________________________________ABSTRACT / The construction of dams and hydroelectric power plants has promoted the economic development of nations for more than a century. The control and stabilization of spillways, irrigation, water provision and electric power generation are among the several uses of dams. The industrial development was implanted late in Brazil, provoking migrations and accelerating the urban growth. This phenomenon came accompanied, in the last decades, by demands from the agricultural technological sector; a process that has caused a greater demand for water and energy supply. As a response to this increasing need, in Goiás, a state located in the central-west of the country, it was built Corumbá Hydroelectric Power Plant IV. It is one of the greatest undertakings directed to the development and the regional infrastructure, above all for the Federal District, which is near this region. However, its project, though considered innovative, has caused polemics since its concession. Moreover, the construction works of the power plant and its reservoir have been provoking significant changes in the nearby districts, particularly in the traditional rural communities. Thus, the goal of this dissertation is to analyze the socio-spatial effects of the hydroelectric reservoir of Corumbá IV, giving emphasis to the land use planning of surrounding districts. Findings indicate that there are limitations and inherent contradictions to land use planning and sustainable development which submit to certain conditions the scope of social agreement that should promote the heterogeneous use of the resources and the land. When analyzing the community's traditional perspective about the undertaking, it was verified with this research, the persistence of a development model whose economic transformations are not accompanied by new alternatives which should represent an improvement in life quality with the inclusion of traditional communities to the processes of contemporary production.
137

Desenvolvimento de catalisadores a base de estanho(IV), para produção de ésteres metílicos de ácidos graxos, via transesterificação e esterificação / Development of tin-based catalysts to produce methyl esters of fatty acid via transesterification and esterification.

Serra, Tatiana Maciel 29 March 2010 (has links)
The catalytic activity of metal complex exhibiting Lewis acid character (dibutyltin diacetate, dibutyltin dilaurate, butylstannoic acid and di-n-butyl-oxostannane) was investigated. These catalytic complexes have been tested in the alcoholysis of soybean and castor oils, aiming to obtain a mixture of fatty acid alkyl esters, called biodiesel. In the transesterification experiments of vegetable oils, the reactions were performed using three types of reactors. The first one consisted in a glass reactor connected to a reflux condenser (RVCR). The second device consisted of a stainless steel reactor (RP), hermetically sealed, fitted with a pressure gauge and a temperature controller. The third one was adapted to be used on a microwave system. On the last two reactor systems, the alcoholysis of triglycerides was also developed at vigorous conditions, at temperatures ranging from 80 °C and 150 °C. Comparing all reactions, the results show that the most reactive catalysts using the RVCR on the methanolysis of soybean oil are DBTDA and DBTDL with comparable performances. However, in the same reaction conditions, very low yields were observed using castor oil, and no generalizations could be pointed out. When RP were employed, better yields were obtained. When the temperature raise from 80 to 150 ºC, all catalytic systems display similar performances, indicating that temperature and solubility have significant influences on these type of catalytic systems. Very low reaction yield were observed when the microwave reactor was employed. This observation must be due to the very low rate of stirring performed on this type of reactor. In a second part of this work, it was evaluated the performance of catalysts based on tin oxide (SnO2), sulfated or not, in transesterification or esterification reactions of soybean oil and its fatty acids derivatives, respectively, in the presence of methanol. The low activity verified on these systems must be related to their structural characteristics. / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Neste trabalho foi investigada a atividade catalítica de quatro complexos metálicos exibindo caráter ácido de Lewis: dibutildiacetato de estanho, dibutildilaurato de estanho, óxido de dibutil estanho e ácido butilestanóico. Esses complexos catalíticos foram testados na alcoólise do óleo de soja e de mamona, visando a obtenção de uma mistura de ésteres alquílicos de ácidos graxos, denominada biodiesel. Nos experimentos de transesterificação dos óleos vegetais, as reações foram realizadas em três tipos de reatores. O primeiro equipamento foi composto de um reator de vidro acoplado a um condensador de refluxo (RVCR). O segundo equipamento foi composto de um reator de aço inox (RP), hermeticamente fechado, equipado com um manômetro e um controlador de temperatura. O terceiro reator empregado era adaptado para ser utilizado em um sistema de microondas. Nos dois últimos sistemas de reatores, a alcoólise dos triglicerídeos foi desenvolvida em condições mais enérgicas de reação, em temperaturas que variaram entre 80 °C e 150 °C. Comparando-se todas as reações, os resultados obtidos indicam que o emprego do RVCR na metanólise do óleo de soja, os catalisadores mais ativos são o DBTDA e o DBTDL com desempenhos comparáveis. Por outro lado, empregando-se o óleo de mamona, nessa condição reacional, os rendimentos foram muito baixos, não permitindo obter generalizações. Quando do uso do RP, rendimentos superiores aos observados com o RVCR são obtidos e à medida que a temperatura aumenta de 80 a 150 ºC as reatividades dos sistemas catalíticos tornam se bastante semelhantes, indicando que fatores como temperatura e solubilidade têm influência significativa nesse tipo de sistemas catalíticos. Com o emprego do reator microondas, os rendimentos reacionais foram inferiores, provavelmente devido à baixa velocidade de agitação que tal reator pode realizar. Numa segunda parte do trabalho, foi realizado um estudo do desempenho de catalisadores a base de óxido de estanho (SnO2), sulfatado ou não, em reações de transesterificação ou esterificação de óleo de soja e seus ácidos graxos, respectivamente, na presença de metanol. A baixa atividade dos catalisadores foi relacionada às características texturais dos mesmos.
138

Caracterização molecular e demografia histórica de populações do camarão sete-barbas - Xiphopenaeus Kroyeri - (Heller 1889) do sudoeste do Atlântico por meio de polimorfismos de microssatélites e do gene COI

Piergiorge, Rafael Mina January 2013 (has links)
Made available in DSpace on 2015-11-18T13:19:30Z (GMT). No. of bitstreams: 2 rafael_piergiorge_ioc_mest_2013.pdf: 1065627 bytes, checksum: 76cbdb2a4d850d707ebf2b5a419be9ee (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2015-04-14 / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil / Xiphopenaeus kroyeri (Heller, 1862) é uma das espécies brasileiras mais importantes comercialmente, sendo explotada em toda a costa, principalmente nas regiões Sul e Sudeste. A partir da década de 60 sua explotação apresentou um grande crescimento, com oscilações até a década de 80. No entanto, após a década de 80 ocorreu um grande declínio na captura e, no período de 1990-1994, estão registrados os mais baixos valores das últimas décadas. Desde então o recurso encontra-se no limite de sustentabilidade. Em 2006, foram identificadas duas espécies crípticas em Xiphopenaeus no Atlântico. Entretanto, os órgãos responsáveis desconsideram essa informação, o que provavelmente acarretará consequências graves para uma ou ambas as espécies. O presente trabalho teve como objetivo: (1) ajustar as condições de amplificação de loci EPIC e caracterizar populações das duas espécies; (2) realizar análise populacional e demográfica histórica de Xiphopenaeus sp. I, em dez pontos ao longo da costa, através de polimorfismos do gene COI; e (3) ajustar as condições de amplificação de loci microssatélites e analisar quatro populações do Brasil. Apesar de resultarem em amplificações, os marcadores EPIC foram monofórmicos nas duas espécies. Em relação ao marcador COI, oito novos haplótipos foram observados para Xiphopenaeus sp. I e cinco para Xiphopenaeus sp. II, totalizando quinze e oito haplótipos descritos, respectivamente. Apesar da identificação de novos haplótipos, o sistema de identificação molecular descrito para a identificação das espécies, continua válido As análises de \0444 apontaram que a população de Caracas (Venezuela) é geneticamente diferenciada das localidades brasileiras, enquanto que, no Brasil, Poças é diferente de Ubatuba, Santos e Cananéia. Por meio de análises de variância, confirmou-se a existência de uma separação pela ressurgência próxima de Cabo Frio. Foi verificado também que Xiphopenaeus sp. I sofreu expansão há 99,57 mil anos, provavelmente na última glaciação. Com microssatélites, apenas as análises de variância resultaram em valores significativos. Ao fim do estudo, os dados obtidos foram agrupados com informações prévias e foi construída uma distribuição consensual para a espécie. Todos esses resultados trazem importantes contribuições para o manejo de Xiphopenaeus spp, pois, além da existência de duas espécies, Xiphopenaeus sp. I é constituída por pelo menos oito estoques geneticamente diferenciados. Este é o primeiro trabalho a realizar uma amostragem tão ampla em um estudo populacional da espécie. Além disso, os dados produzidos servirão como parâmetro de comparação para outros estudos de organismos marinhos da região / Xiphopenaeus kroyeri (Heller, 1862), is one of Brazil's most important c ommercial species being exploited across the coast mostly in the South and Southeast. From the 60's its exploitation showed large growth, with fluctuations up to the 80, but after the 80's there was a huge decline in the catch and in the period 1990-1994, are recorded the lowest values of decades. Since then t he resource is within the limits of sustainability. In 2006 were identified two cryptic species in Xiphopenaeus in the Atlantic. However, the agencies responsible disrega rd this information, which probably will result in consequences for one or bot h species. This study focus to: (1) optimize the amplification conditions of EPIC loci and characterize populations of the two species, (2) perform analysis of historical dem ographic and population Xiphopenaeus sp. I, in ten points along the coast, through COI gene polymorphisms, and (3) standardize the amplification conditions of microsatellite loci and analyze four populations of Brazil. Despite the amplifications, EPIC markers were monomorphic in both species. In COI marker, eight new haplotypes w ere observed for Xiphopenaeus sp. I and five Xiphopenaeus sp. II, totaling three eight haplotypes. Even with the identification of new haplotypes, the identificatio n system described for molecular identification of species remains valid. The Φ analysis showed that Venezuela is differentiated from Brazilian localities, while in Brazil Poças is different from Ubatuba, Santos and Cananéia. Through variance analysis was confirmed the existence of a separation next of the upwelling in Cabo Frio. We a lso noticed that Xiphopenaeus sp. I expanded on 99,570 years ago, probably in the las t glaciation. Using microsatellites markers, the variance analysis was the only with si gnificants values. At the end of this study, the data were clustered with previous i nformations and the consensus distribution was constructed for the species. All t hese results supply contributions to management of Xiphopenaeus spp., because beyond the existence of two species, Xiphopenaeus sp. I consists of at least eight genetically diffe rent stocks. This is the first work to perform as wide a sampling in a study population of the species. In addition, the data produced will serve as a point o f reference for other studies of marine organisms in the region.
139

Território usado e a produção social do turismo na Usina Hidrelétrica Corumbá IV

Castro, Marinez Caetano de 28 March 2014 (has links)
Dissertação (mestrado)—Universidade de Brasília, Programa de Pós-Graduação em Geografia, 2014. / Submitted by Raquel Viana (raquelviana@bce.unb.br) on 2014-09-10T20:18:05Z No. of bitstreams: 1 2014_MarinezCaetanodeCastro.pdf: 16413521 bytes, checksum: b038c7f8ad7b46abcd59701af67756e4 (MD5) / Approved for entry into archive by Raquel Viana(raquelviana@bce.unb.br) on 2014-09-10T20:19:40Z (GMT) No. of bitstreams: 1 2014_MarinezCaetanodeCastro.pdf: 16413521 bytes, checksum: b038c7f8ad7b46abcd59701af67756e4 (MD5) / Made available in DSpace on 2014-09-10T20:19:40Z (GMT). No. of bitstreams: 1 2014_MarinezCaetanodeCastro.pdf: 16413521 bytes, checksum: b038c7f8ad7b46abcd59701af67756e4 (MD5) / O reservatório da Usina Hidrelétrica Corumbá IV é tratado, neste mestrado, com foco na dinâmica social do turismo, na perspectiva do território usado e de noções geográficas discutidas por Milton Santos, a saber: 1. Formas-conteúdo: arranjo ordenado de objetos formais que guardam uma essência; 2. Função: que traz o sentido das formas turísticas analisadas; 3. Estrutura: inter-relação dos elementos avaliados com o todo que os envolvem; 4. Processo: ação contínua que se desenvolve em relação a um resultado esperado, implica mudança socioespacial ligada à atividade avaliada e tempo de permanência. A abordagem metodológica foi construída no intuito de captar o movimento do objeto que buscamos compreender, a partir da análise das categorias co-presença, da interação (vizinhança) e das normas, todas vinculadas ao debate sobre o turismo, neste caso, no reservatório da UHE Corumbá IV. Tais categorias aplicadas ao estudo de caso possibilitaram enxergar os conflitos sociais de uso do território e as contradições processuais existentes nas interfaces dos usos múltiplos da água com o turismo e particularmente sobre o turismo, contradições estas, das quais o Estado se apresenta aquém de suas possibilidades e das necessidades territoriais, sobretudo nos locais averiguados neste estudo. O método de análise foi desenvolvido com base no pensamento dialético, para identificação das contradições dos diferentes aspectos de uma mesma realidade do território, bem como as interfaces dos usos existentes com o turismo. Com o objetivo de analisar a dinâmica de uso do território a partir do turismo, os principais procedimentos metodológicos foram, entrevistas de campo, campo exploratório, análise de relatório e cartografia temática. ______________________________________________________________________________ ABSTRACT / The reservoir of Corumbá IV hydroelectric dam (UHE Corumbá IV) is discussed in this master´s degree focusing in the social dynamics of tourism from the used territory viewpoint and geographical notions studied by Milton Santos, namely: 1. Forms-Content: ordered arrangement of formal objects that keep an essence; 2. Function: it brings the meaning of touristic forms analyzed; 3. Structure: interrelationship of the elements assessed with all involving; 4. Process: continuous action that develops in a direction expected result, implying sociospatial changes linked to evaluated activity and time duration. The methodological approach was developed starting from capture the meaning of the object that we search to understand, from the categorical analysis of the co-presence, interaction (neighborhood) and the rules, all connected to the discussion about the tourism, in this instance the reservoir of UHE Corumbá IV. These categories applied to the study case allow seeing the social conflicts of territory’s use and the procedural contradictions, existing at the interfaces of water multiple uses for tourism and especially on tourism, such contradictions, of which the State is presented below their potential and territorials needs, especially in the investigated places in this study. The method of analysis has been developed based on dialectical thought, to identify contradictions of different aspects of the same territory’s reality , as well as the interfaces of the tourism with its uses. With the goal to analyze the dynamics of the tourism territory’s use for tourism, the main methodological procedures were field interviews, field exploration, analysis, reporting and thematic cartography.
140

Structural Characterization and Optical Properties of Group IV Semiconductor Alloys

January 2014 (has links)
abstract: ABSTRACT This thesis focuses on structural characterizations and optical properties of Si, Ge based semiconductor alloys. Two material systems are characterized: Si-based III-V/IV alloys, which represent a possible pathway to augment the optical performance of elemental silicon as a solar cell absorber layer, and Ge-based Ge1-ySny and Ge1-x-ySixSny systems which are applicable to long wavelength optoelectronics. Electron microscopy is the primary tool used to study structural properties. Electron Energy Loss spectroscopy (EELS), Ellipsometry, Photoluminescence and Raman Spectroscopy are combined to investigate electronic band structures and bonding properties. The experiments are closely coupled with structural and property modeling and theory. A series of III-V-IV alloys have been synthesized by the reaction of M(SiH3)3 (M = P, As) with Al atoms from a Knudsen cell. In the AlPSi3 system, bonding configurations and elemental distributions are characterized by scanning transmission electron microscopy (STEM)/EELS and correlated with bulk optical behavior. The incorporation of N was achieved by addition of N(SiH3)3 into the reaction mixture yielding [Al(As1-xNx)]ySi5-2yalloys. A critical point analysis of spectroscopic ellipsometry data reveals the existence of direct optical transitions at energies as low as 2.5 eV, well below the lowest direct absorption edge of Si at 3.3 eV. The compositional dependence of the lowest direct gap and indirect gap in Ge1-ySny alloys extracted from room temperature photoluminescence indicates a crossover concentration of yc =0.073, much lower than virtual crystal approximation but agrees well with large atomic supercells predictions. A series of Ge-rich Ge1-x-ySixSny samples with a fixed 3-4% Si content and progressively increasing Sn content in the 4-10% range are grown and characterized by electron microscopy and photoluminescence. The ternary represents an attractive alternative to Ge1-ySny for applications in IR optoelectronic technologies. / Dissertation/Thesis / Ph.D. Physics 2014

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