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S?ntese e caracteriza??o de NiO-CGO para anodo e eletr?litos s?lidos e base de C?ria para SOFCCella, Beatriz 04 January 2009 (has links)
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Previous issue date: 2009-01-04 / The direct use of natural gas makes the Solid Oxide Fuel Cell (SOFC) potentially more competitive with the current energy conversions technologies. The Intermediate Temperature SOFC (IT-SOFC) offer several advantages over the High
Temperature SOFC (HT-SOFC), which includes better thermal compatibility among components, fast start with lower energy consumption, manufacture and operation cost reduction. The CeO2 based materials are alternatives to the Yttria Stabilized
Zirconia (YSZ) to application in SOFC, as they have higher ionic conductivity and less ohmic losses comparing to YSZ, and they can operate at lower temperatures (500-800?C). Ceria has been doped with a variety of cations, although, the Gd3+ has the ionic radius closest to the ideal one to form solid solution. These electrolytes based in ceria require special electrodes with a higher performance and chemical and termomechanical compatibility. In this work compounds of gadolinia-doped ceria, Ce1-xGdxO2-δ (x = 0,1; 0,2 and 0,3), used as electrolytes, were synthesized by polymeric precursors method, Pechini, as well as the composite material NiO - Ce0,9Gd0,1O1,95, used as anode, also attained by oxide mixture method, mixturing the powders of the both phases calcinated already. The materials were characterized by X ray diffraction, dilatometry and scanning electronic microscopy. The refinement of the diffraction data indicated that all the Ce1-xGdxO2-δ powders were crystallized in a
unique cubic phase with fluorite structure, and the composite synthesized by Pechini method produced smaller crystallite size in comparison with the same material attained by oxide mixture method. All the produced powders had nanometric
characteristics. The composite produced by Pechini method has microstructural characteristics that can increase the triple phase boundaries (TPB) in the anode, improving the cell efficiency, as well as reducing the mass transport mechanism
effect that provokes anode degradation / A utiliza??o direta do g?s natural torna a c?lula a combust?vel de ?xido s?lido (SOFC) potencialmente mais competitiva com as atuais tecnologias para convers?o de energia. A SOFC de temperatura intermedi?ria (IT-SOFC) oferece muitas
vantagens sobre a SOFC de alta temperatura (HT-SOFC), que incluem melhor compatibilidade t?rmica entre os componentes, partida r?pida com menos consumo energ?tico, redu??o de custos de obten??o e opera??o. Os materiais baseados em
CeO2 s?o alternativas aos eletr?litos de zirc?nia estabilizada com ?tria (YSZ) para aplica??es em SOFC, pois t?m condutividade i?nica maior e menores perdas ?hmicas em compara??o a YSZ, e podem operar a temperaturas mais baixas (500-800?C). C?ria tem sido dopada com uma variedade de c?tions, entretanto, o Gd3+ possui o raio i?nico mais pr?ximo do ideal para forma??o da solu??o s?lida. Esses
eletr?litos baseados em c?rio requerem eletrodos especiais com um alto desempenho e compatibilidade termomec?nica e qu?mica. Neste trabalho compostos c?ria dopada com gadol?nia, Ce1-xGdxO2-δ (x = 0,1; 0,2 e 0,3), utilizadas como
eletr?litos, foram sintetizados a partir do m?todo dos precursores polim?ricos, Pechini, assim como o material comp?sito NiO - Ce0,9Gd0,1O1,95, usado para anodo,
obtido tamb?m pelo m?todo de mistura dos ?xidos, p?s das duas fases j? calcinadas. Os materiais foram caracterizados atrav?s das t?cnicas de difra??o de raios X, dilatometria e microscopia eletr?nica de varredura. O refinamento dos dados
obtidos pela difra??o de raios X indicou que todos os p?s de Ce1-xGdxO2-δ cristalizaram em uma ?nica fase c?bica com estrutura fluorita, e que o comp?sito obtido por Pechini produziu menores tamanhos de cristalitos das fases em
compara??o com o p? sintetizado por mistura de ?xidos em uma mesma temperatura de calcina??o. Todos os p?s obtidos t?m caracter?sticas nanom?tricas. O comp?sito obtido por Pechini possui caracter?sticas microestruturais que podem
aumentar a fronteira de fase tripla (TPB) dentro do anodo, melhorando a efici?ncia da c?lula, assim como reduzir o efeito do mecanismo de transporte de massa que provoca degrada??o do anodo
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Estudo da influ?ncia da temperatura de brasagem nas uni?es zirc?nia/a?o inox 304 utilizando metaliza??o mec?nica / Study on the influence of brazing temperature in the joint zirconia/steel using mechanical metallizationCarneiro, Jaciane Mora?sa 30 July 2014 (has links)
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Previous issue date: 2014-07-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Metal-Ceramic (M/C) Zirconia-stainless steel interfaces have been processed through brazing techniques due to the excellent combination of properties such as high temperature stability, high corrosion resistance and good mechanical properties. However, some M/C interfaces show some defects, like porosity and cracks results in the degradation of the interfaces, leading even to its total rupture. Most of time, those defects are associated with an improper brazing parameters selection to the M/C system. In this work, ZrO2 Y-TZP and ZrO2 Mg - PSZ were joint with the stainless steel grade 304 by brazing using a eutectic silver-copper (Ag28Cu) interlayer alloy with different thermal cycles. Ceramic surfaces were previous mechanically metallized with titanium to improve adhesion of the system. The effect of temperature on the M/C interface was studied. SEM-EDS and 3 point flexural bend test were performed to evaluate morphology, chemical composition and mechanical resistance of the M/C interfaces. Lower thermal cycle temperatures produced better results of mechanical resistance, and more regular/ homogeneous reaction layers between braze alloy and metal-ceramic surfaces. Also was proved the AgCu braze alloy activation in situ by titanium / Interfaces metal/cer?mica zirc?nia/a?o inox processadas via brasagem v?m sendo utilizadas devido a sua combina??o de propriedades tais como: estabilidade em altas temperaturas, elevada resist?ncia ? corros?o e boas propriedades mec?nicas. Contudo, alguns pares apresentam problemas a n?vel da interface, como trincas, fissuras e porosidades, contribuindo assim para a deteriora??o do par metal/cer?mica, podendo at? conduzir ? ruptura total da interface. Esses defeitos na interface podem estar associados a uma sele??o menos criteriosa dos par?metros de brasagem para cada sistema. No presente trabalho utilizou-se a uni?o entre zirc?nia (Y-TZP e Mg PSZ) com a?o inox 304. Essas jun??es foram metalizadas mecanicamente com Ti e brasadas em diferentes ciclos t?rmicos utilizando liga de adi??o Ag-Cu. Microscopia Eletr?nica de Varredura (MEV) com microan?lise por espectroscopia de Energia Dispersiva (EDS) e teste de flex?o em 3 pontos foram empregadas para investigar as propriedades da uni?o zirc?nia/a?o. Os resultados revelaram que para menores temperaturas de brasagem houve uma melhor resist?ncia a flex?o e camadas de rea??o mais homog?neas entre a liga de adi??o e os pares metal/cer?mica. Ficou tamb?m comprovado a ativa??o in situ da liga de adi??o AgCu
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Estudo da viabilidade do processo de reciclagem do material descartado do sistema Zirkonzanh? de produ??o de pr?teses dent?riasSilva, Yankel Bruno Fontes 17 March 2014 (has links)
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Previous issue date: 2014-03-17 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / At present, the material of choice for performing aesthetic dental prosthetic work is in the ceramic. Among them, the ceramic base of stabilized zirconia with 3% yttria (3Y - TZP) stand out for having excellent physical and mechanical properties. During the machining of blocks of zirconia in the laboratory to prepare the various types of prostheses, much of the material is given off in the form of powder, which is subsequently discarded. The waste of this material results in financial loss, reflecting higher final cost treatment for patients, as well as damage to the environment, thanks to the processes involved in the manufacture and disposal of the ceramic. This research, pioneered the recycling of zirconium oxide powder obtained during milling of dental crowns and bridges, we highlight the social and environmental aspects and aims to establish a protocol for the reuse of waste (powder of zirconia Zirkonzahn? system) discarded to obtain a new block of compacted zirconia to maintain the same mechanical and microstructural properties of commercial high-cost imported material. To compare with the commercial material, samples were uniaxially (20 MPa) and isostatically (100 MPa), and its mechanical and microstructural characterization was performed through tests of density, porosity, dilatometry, X-ray diffraction (XRD), hardness, fracture toughness, resistance to fracture electron microscopy (SEM) and analysis of grain size. The results observed in the samples were isostatically pressed similiares those obtained with samples from the commercial material demonstrating the viability of the process / Na atualidade, o material de escolha para execu??o de trabalhos prot?ticos est?ticos em odontologia ? o cer?mico. Dentre eles, as cer?micas a base de zirc?nia estabilizada com 3% de ?tria (3Y-TZP) se destacam por apresentarem excelentes propriedades f?sicas e mec?nicas. Durante a usinagem dos blocos de zirc?nia em laborat?rio para preparo dos diversos tipos de pr?tese, grande parte do material ? desprendida na forma de p?, que posteriormente ? descartado. O desperd?cio deste material resulta em preju?zo financeiro, refletindo em elevado custo final no tratamento para os pacientes, al?m de preju?zo para o meio ambiente, devido aos processos envolvidos na fabrica??o e descarte da cer?mica. Esta pesquisa, pioneira na reciclagem do p? de ?xido de zirc?nia obtido durante a fresagem de coroas e pontes dent?rias, destaca-se nos aspectos social e ambiental e tem como objetivo, estabelecer um protocolo de reaproveitamento de res?duos (p? de zirc?nia do sistema Zirkonzahn?) descartados para a obten??o de um novo bloco de zirc?nia compactado que mantenha as mesmas propriedades mec?nicas e microestruturais do material comercial importado de alto custo. Para comparar com o material comercial, as amostras foram prensadas uniaxialmente (20 MPa) e isostaticamente (100 MPa), e sua caracteriza??o mec?nica e microestrutural foi realizada atrav?s dos ensaios de densidade, porosidade aparente, dilatometria, difra??o de raios X (DRX), microdureza, tenacidade a fratura, resist?ncia a fratura, microscopia eletr?nica de varredura (MEV) e an?lise de tamanho de gr?o. Os resultados constatados nas amostras prensadas isostaticamente foram similiares ?queles obtidos com as amostras do material comercial demostrando a viabilidade do processo
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Inquisi??o em Vila Rica setecentista: aspectos das pr?ticas inquisitoriais no per?odo compreendido entre 1711 e 1750Colen, Dalvan Charbaje 20 September 2017 (has links)
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Previous issue date: 2017 / Este trabalho se desenvolveu atrav?s de pesquisas e contribui??es com a tem?tica Inquisi??o e seus aspectos Inquisitoriais, na busca de abstrair a atua??o do Tribunal do Santo Of?cio em Vila Rica - Minas Gerais, seus desdobramentos e experi?ncias nas primeiras d?cadas do s?culo XVIII. Ter acesso a documentos prim?rios da Inquisi??o, no inicio da forma??o territorial de Vila Rica viabilizou compreender mais a realidade do Santo Of?cio, os seus interesses e como atuavam, tendo em vista o car?ter m?ltiplo de julgador, controlador e repressor, atuando aparentemente como ide?rio da manuten??o da f? Cat?lica. Assim, selecionou-se Vila Rica, por se tratar de uma das principais Vilas no per?odo colonial do Brasil. Logo, houve delimita??o do espa?o e tempo; vale relatar que o principal expoente Inquisitorial em Vila Rica eram os Crist?os-Novos (1711-1750). / Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o em Tecnologia, Sa?de e Sociedade, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / This work was developed through researches and contributions with the Inquisition and its Inquisitorial aspects, in the quest to abstract the actions of the Court of the Holy Office in Vila Rica - Minas Gerais, its developments and experiences in the first decades of the 18th century. Having access to primary documents of the Inquisition, at the beginning of the territorial formation of Vila Rica made it possible to understand more the reality of the Holy Office, its interests and how they acted, considering the multiple character of a judge, controller and repressor, apparently acting as maintenance of the Catholic faith. Thus, Vila Rica was selected because it is the main towns in the colonial period of Brazil. Therefore, there was delimitation of space and time; it is worth mentioning that the main Inquisitorial exponent in Vila Rica was the New-Christians (1711-1750).
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Desenvolvimento, sustentabilidade e conserva??o da biodiversidade na amaz?nia: a produ??o familiar agroextrativista em ?reas protegidas no sul do amap?Pican?o, Jos? Reinaldo Alves 04 December 2010 (has links)
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Previous issue date: 2010-12-04 / The establishment of Extractivism and Sustainable Development Reserves comes from an amazon forestry people resistance initiative. It means an option of natural resources management as protected areas for agroextractivism purposes. According to the institutional point of view, these lands, called Conservation Unity for Sustainable Exploration, belong to the government which grants the usufruct rights to the agroextractivist families
under a sharing territory administration agreement among government and rural communities. The main roles of these lands are both: to improve the dwellers wellbeing, and protecting the local biodiversity. Additionally, they also represent the start of this thesis theme entitled Development, sustainability, and biodiversity conservation in the Amazon region: the use of protected areas for agroextractivism domestic yield in south of Amap? state with the objective of analyzing the performance that each territory has been reaching in terms of the attributions proposed at the beginning, when they were created. Social, economics, and environment changes that occurred in the agroextractivist areas have been evaluated from two selected test sites, named Rio Cajari Extractivist Reserve and Rio Iratapuru Sustainable Reserve, both, localized in the south of Amap? state / A cria??o de Reservas Extrativistas e Reservas de Desenvolvimento Sustent?vel, surgem a partir do movimento de resist?ncia dos povos da floresta amaz?nica, e representa uma alternativa de gest?o dos recursos naturais sob a forma de ?reas protegidas destinadas ao agroextrativismo. Do ponto de vista institucional, esses espa?os territoriais s?o Unidades de Conserva??o de Uso Sustent?vel, pertencentes ao poder p?blico, que concede o direito de usufruto ?s fam?lias agroextrativistas, num processo gest?o compartilhada desses territ?rios entre o poder p?blico e as representa??es comunit?rias. Essas ?reas t?m duplo objetivo, promover a melhoria das condi??es de vida dos moradores e garantir a prote??o da biodiversidade local. Esses objetivos constituem o ponto de partida desta tese Desenvolvimento, sustentabilidade e conserva??o da biodiversidade na Amaz?nia: a produ??o familiar agroextrativista em ?reas protegidas no sul do Amap?, que busca analisar em que medida esses territ?rios est?o cumprindo com as finalidades para as quais foram criados. A pesquisa foi realizada na Reserva Extrativista do Rio Cajari e na Reserva de Desenvolvimento Sustent?vel do Rio Iratapuru, localizadas no sul do estado do Amap?, analisando as mudan?as sociais, econ?micas e ambientais, ocorridas nessas ?reas agroextrativistas
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Reserva extrativista do Rio Cajari: verso e reverso da territorializa??o no sul do Amap?Pican?o, Jos? Reinaldo Alves 08 March 2005 (has links)
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Previous issue date: 2005-03-08 / The creation of Extractive Reserves (RESEX s) emerges from the resistence movement of the forest people and represents an alternative administration of the naturel resources in the from of Conservation Units (UC). From the institutional point of view the RESEX s are UC s of direct use belong of the Brazilian State, which concedes the right of use to resident families through a legal concession, uhich in based an the principle of coadministration between state and community. The use of these areas is based on the paradigm of sustainable development. In the Extractive Reserve of Rio Cajari over time there has been an experience of confliting interests between the big capital and the local population, which led to noticiable changes of lifestyle of the rural extrativist. In this sense the essay Extractive Reserve of Rio Cajari: various aspects of land use and awnership in southem Amapa , wants to analyse the nuances in which the land grabbing happened and how it affected the day to day of life its in habitants / A cria??o das Reservas Extrativistas RESEXs, surge a partir do movimento de resist?ncia dos povos da floresta , e representa uma alternativa de gest?o dos recursos naturais sob a forma de Unidade de Conserva??o UC. Do ponto de vista institucional, as RESEXs s?o UCs de uso direto, pertencentes ? Uni?o, que concede o direito de usufruto ?s fam?lias residentes, atrav?s da Concess?o Real de Uso, que tem como base um Plano de Utiliza??o, calcado sobre o paradigma do desenvolvimento sustent?vel. Assim, esses espa?os se constituem em territ?rios das popula??es tradicionais , baseados no princ?pio a co-gest?o entre o Estado e as representa??es comunit?rias. Na Reserva Extrativista do Rio Cajari, no decorrer do processo de luta pela terra frente ao grande capital, bem como na co-gest?o do territ?rio conquistado, in?meros conflitos s?o vivenciados pela popula??o local, desencadeando um conjunto de situa??es que passaram a influenciar seu modo de vida, marcando indelevelmente o ethos do agroextrativista. Desse modo, com este trabalho Reserva Extrativista do Rio Cajari: verso e reverso da territorializa??o no sul do Amap?, procura-se analisar as nuances do processo de apropria??o territorial ocorrida na ?rea, bem como a dimens?o das mudan?as no estilo de vida da popula??o
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Metaliza??o mec?nica de ZrO2 com Ti para brasagem ZrO2/A?o com ligas de adi??o sem metal ativoSilva, Jo?o Moreno Vilas Boas de Souza 21 December 2011 (has links)
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Previous issue date: 2011-12-21 / Metal/ceramic interfaces using zirconia have dominated the industrial
applications in the last decade, due to the high mechanical strength and fracture
toughness of zirconia, especially at temperatures below 300 ?C. Also noteworthy is the
good ionic conductivity in high temperatures of this component. In this work joining
between ZrO2 Y-TZP and ZrO2 Mg-PSZ with austenitic stainless steel was studied.
These joints were brazed at high-vacuum after mechanical metallization with Ti using
filler alloys composed by Ag-Cu and Ag-Cu-Ni. The influence of the metallization, and
the affinity between the different groups (ceramic / filler alloys) was evaluated, in order
to achieve strong metal/ceramic joints. Evaluation of joints and interfaces, also the
characterization of base materials was implemented using various techniques, such as:
x-ray diffraction, leak test, three-point flexural test and scanning electron microscopy
with chemical analysis. The microstructural analysis revealed physical and chemical
bonds in the metal/ceramic interfaces, providing superior leak proof joints and stress
cracking, in order to a good joint in all brazed samples. Precipitation zones and reaction
layers with eutetic characteristics were observed between the steel and the filler metal / As interfaces metal/cer?micas utilizando zirc?nia t?m dominado as
aplica??es industriais na ?ltima d?cada, em virtude da alta resist?ncia
mec?nica e tenacidade ? fratura da zirc?nia, especialmente em temperaturas
abaixo de 300 ?C. Destaca-se tamb?m a boa condutividade i?nica em
temperaturas elevadas deste componente. No presente trabalho, estudou-se as uni?es
entre ZrO2 Y-TZP e ZrO2 Mg-PSZ com o a?o inox austen?tico 304. Estas jun??es foram
produzidas por brasagem a alto-v?cuo ap?s a metaliza??o mec?nica com Ti utilizandose
ligas de adi??o compostas por Ag-Cu e Ag-Cu-Ni. Avaliou-se a influ?ncia da
metaliza??o, bem como a afinidade entre os diversos grupos (cer?mica / liga de adi??o)
com o intuito de se conseguir a melhor uni?o metal/cer?mica. A avalia??o das uni?es e
interfaces, bem como a caracteriza??o dos materiais de base foi feita com recurso de
diversas t?cnicas, tais como: difra??o de raios-x, ensaios de estanqueidade, flex?o em 3-
pontos e microscopia eletr?nica de varredura com microan?lise por espectroscopia de
energia dispersiva de raios-x. A an?lise microestrutural revelou liga??es f?sicas e
qu?micas na interface metal/cer?mica, proporcionando boa estanqueidade e tens?o de
ruptura e, consequentemente, uma boa uni?o em todas as amostras brasadas. Foram
observadas zonas de precipita??o e camadas de rea??o com caracter?sticas eut?ticas
entre o a?o e o metal de adi??o
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Qualidade subjetiva do sono e queixa de ins?nia em pacientes com Acidente Vascular CerebralRocha, Patr?cia Cavalcanti da 12 December 2008 (has links)
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Previous issue date: 2008-12-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Brain injury can be associated with changes in the sleep-wake cycle. However, studies about sleep disturbances and their relationship with quality of sleep are scarce. Besides, it remains to be known how stroke affects the mechanisms of sleep. The aim of this study was to investigate quality of sleep, complaints of sleep disturbances and associated factors in stroke patients from the Physical Therapy services in Natal -RN. This was a cross-sectional descriptive study involving 70 individuals (aged 45-65 years), 40 patients (57 ? 7 years), 11 ? 9 months after injury, and 30 healthy individua ls (52 ? 6 years), evaluated with the Pittsburgh Sleep Quality Index (PSQI) and Sleep Habits Questionnaire. The data were analyzed by Chi-square test, t Student test and logistic regression. Poor quality sleep was found in 57,5% of the patients (6,3 ? 3,5) and was significantly higher than in the control population (3,9 ? 2,2) (t Student test, p=0,002). The patients showed significantly higher value of PSQI than controls: sleep latency (p=0,019), length of sleep (p=0,039) and dysfunction during the day (p=0,001). Regarding complaints of sleep disturbances (dyssomnias and parasomnias) analyzed by Chi-square test, the complaint of insomnia was the most prevalent (patients: 37,5%; healthy subjects: 6,7%; p=0,007). Regression analysis showed that sl eep latency (p=0,036) and complaint of insomnia (p=0,036) were associated with quality sleep. In addition, female gender (p=0,036) and complaint of broken sleep (p=0,003) were considered risk factors for the presence of insomnia. Our results show that stroke affects the homeostatic process of sleep. Shorter sleep latency and the absence of insomnia are considered protective factors for good sleep quality and this should be taken into consideration in the diagnostic and therapeutic strategies / A les?o cerebral pode estar associada a altera??es do ciclo sono-vig?lia. No entanto, estudos sobre dist?rbios do sono e suas rela??es com a qualidade de sono s?o raros. Al?m disso, ainda precisa ser conhecido como o Acidente Vascular Cerebral (AVC) afeta os mecanismos do sono. O objetivo deste estudo foi investigar a qualidade de sono, as queixas de dist?rbios do sono e os fatores associados nos pacientes com AVC de servi?os de Fisioterapia em Natal-RN. Este foi um estudo transversal e volvendo 70 indiv?duos (idade 45-65 anos) , 40 pacientes (57 ? 7 anos), 11 ? 9 meses ap?s a les?o, e 30 saud?veis (52 ? 6 anos), avaliados com o ?ndice de Qualidade de sono de Pittsburgh (IQSP) e o Question?rio de H?bitos do Sono. Os dados foram analisados atrav?s dos testes Qui-quadrado, t Student e da Regress?o Log?stica. Qualidade de sono ruim foi encontrada em 57,5% dos pacientes (6,3 ? 3,5) e foi significativamente maior do que na popula??o controle (3,9 ? 2,2) (teste t Student, p=0,002). Os pacientes apresentaram valor significativamente maior de IQSP do que os controles: lat?ncia para o sono ( p=0,019), dura??o do sono (p=0,039) e disfun??o durante o dia (p=0,001). Com rela??o ?s queixas de dist?rbios de sono (dissonias e parassonias) analisadas pelo Qui-quadrado, a queixa de ins?nia foi a mais prevalente (pacientes: 37,5%; saud?veis: 6,7%; p=0,007). A an?lise de regress?o mostrou que a lat?ncia para o sono (p=0,036) e a queixa de ins?nia (p=0,036) estiveram associadas com qualidade de sono. Al?m disso, o sexo feminino (p=0,036) e a queixa de sono fragmentado (p=0,003) foram considerados fatores de risco para a presen?a de ins?nia. Nossos resultados mostram que o AVC afeta o processo homeost?tico do sono. A menor lat?ncia para o sono e a aus?ncia de ins?nia s?o consideradas fatores de prote??o para a boa qualidade de sono e isso deve ser levado em considera??o nas estrat?gias diagn?stica e terap?utica.
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Otimiza??o de controladores Fuzzy Tipo-2 intervalares utilizando meta-heur?sticasCavalcante, M?rio S?rgio Freitas Ferreira 27 June 2017 (has links)
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Previous issue date: 2017-06-27 / Industrialmente, diversas estrat?gias e algoritmos de controle j? s?o utilizadas e registradas
na literatura. Entre as t?cnicas existentes, os controladores fuzzy destacam-se
pela sua capacidade de tratar de severas n?o linearidades presentes em plantas reais e por
conseguir representar o conhecimento especialista, que ? impreciso e inexato matematicamente.
Este trabalho estudou dois tipos de controladores fuzzy existentes, baseados
no modelo Sugeno, sendo fuzzy tipo-1, aqui classificado como fuzzy convencional, e o
fuzzy tipo-2. Devido a complexidade em sintonizar controladores fuzzy que apresentam
uma grande quantidade de par?metros, esse trabalho se prop?e a testar diferentes m?todos
de otimiza??o meta-heur?sticos para a sintonia de controladores. Para validar os controladores
obtidos foi utilizado um servo motor-DC da Quanser, um problema de controle
que requer precis?o e velocidade na corre??o do erro de segmento da refer?ncia. Com o
intuito de comparar o comportamento dos controladores, otimizou-se um controlador PI
para cada um dos sistemas. Para quantificar e qualificar cada controlador foram utilizados
tr?s ?ndices de avalia??o, ITEA, IEA e o ?ndice de Goodhart, este ?ltimo utilizado por
levar em considera??o tamb?m o sinal de controle aplicado na planta. Pela an?lise dos resultados
obtidos, o controlador fuzzy tipo-2 apresentou ganho significativo para o controle
dessa planta, quando otimizado com o m?todo PSO. Pelos resultados, pode-se tamb?m inferir
que o algoritmo das formigas n?o mostrou-se adequado para esse problema, com a
fun??o de avalia??o proposta. / Differents stategies and control algorithms are already tested and registered by industry.
Among the existing techniques, fuzzy controllers stand out for their ability to deal with
nonlinearities present in real plants. Another fuzzy also allows to best represent expert
knowledge, which is mathematically inaccurate. This proposal studied the two types of
fuzzy controllers, based on Sugeno Model, the fuzzy type-1 is classified as conventional
fuzzy and fuzzy type-2. In this study is used optimization techniques seeking to tune controllers
in order to solve one of the biggest problem in fuzzy logic, its tunning. Ant colony,
particle swarm and genetic algorithm are used and evaluated to this problem. A servo
motor-dc is used to validate fuzzys controllers and pi controller obtained by optimization
tecniques. In order to quantify and qualify each controller, three indices were used IEA,
ITEA and Goodhart index. The results obtained prove that the type-2 fuzzy controller presented
significant gain for the control of this plant, when optimized with the PSO method.
From the results, it can also be inferred that the ant algorithm was not adequate for this
problem, with the proposed evaluation function.
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Compara??o do potencial herbicida do glifosato e seus complexos met?licos atrav?s de estudo enzim?tico e de metab?litos em Glycine max e Brachiaria decumbens / Comparison of herbicide potential of glyphosate and its metal complexes by enzymatic and metabolites studies in Glycine max and Brachiaria decumbensSILVA, Soraia John da 20 August 2015 (has links)
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Previous issue date: 2015-08-20 / CAPES / The glyphosate, herbicide used in different countries, inhibits the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), blocking the synthesis of aromatic amino acids. With this, it still affects the activity of phenylalanine ammonia lyase (PAL) and the concentration of metabolites in plants. Its activity was first reported as a metal chelator. Therefore, to make use of this herbicide, may be formation of complexes with metals from soil, occurring change in the effectiveness of the product and loss of minerals. Thus, to avoid such problems,this study aimed to compare the effectiveness of three forms of glyphosate: purified, previously complexed with metals, and a commercial form (Roundup WG?). The effects of glyphosate complexes with copper, cobalt and nickel with different stoichiometries and different pH values on the in vitro activity of EPSPs were evaluated. Selected complex for the first experiment in vivo were Cu421 and Co821 (first number for pH and the latter two to stoichiometry glyphosate: metal). These complexes were used in the in vivo experiment I, as well as distilled water (control), purified Roundup and glyphosate on transgenic soybean and B. decumbens. In the following experiments (II and III), mineral oil was used in all treatments to reduce leaching of the compounds. The complex selected for continuation of this study was Cu421 due to its emphasis on the results obtained in the first experiment in vivo. When comparing the effect of the compounds in Falker Chlorophyll Index (ICF) of B. decumbens compared to control, there was fall of this index when using Roundup, Cu421 and purified glyphosate (the latter only in the second experiment). Later it was analyzed fresh mass accumulation and collected fresh material for determination of enzyme activities and N-NO3- levels. The complex Cu421 caused a more significant fresh mass reduction and still allowed the increase in the content of soluble nitrate in Brachiaria decumbens, probably due to the presence of nitrate in this complex. In the case of transgenic soybean there was no significant change in ICF. The use of Roundup and the complex did not change significantly the fresh mass accumul ation in this species. The application of the purified glyphosate, however, caused increase in mass accumulation and all treatments altered soybeans in nitrate content. In experiments with mineral oil in B. decumbens, the Cu421 complex inhibited significantly the EPSPs activity, as well as purified Roundup and glyphosate (the latter only in the experiment III). No inhibition occurred in transgenic soybean. All treatments in vivo stimulated PAL activity only on weed, which suggests that the increase in this activity is a consequence of the inhibition of EPSPs and other deleterious effects of compounds on susceptible plants. This study showed that especially Cu421 complex might be used effectively as a herbicide since it inhibits EPSPs, activates the PA,L reduces fresh mass accumulation and influences photosynthesis in the tested weed. Besides, the transgenic soybean showed little sensitive to this compound, which further increases the prospect of using the same as herbicide. / O glifosato, herbicida usado mundialmente, atua inibindo a enzima 5-enolpiruvil-chiquimato- 3-fosfato-sintase (EPSPs), bloqueando a s?ntese de amino?cidos arom?ticos. Com isso, ainda influencia a atividade de fenilalanina am?nia liase (PAL) e a concentra??o de metab?litos nas plantas. A sua primeira a??o reportada foi como agente quelante de metais. Portanto, ao fazer uso deste herbicida, pode haver forma??o de complexos com metais do solo, ocorrendo altera??o da efic?cia do produto e defici?ncia mineral. Assim, de modo a evitar tais problemas, este trabalho teve como objetivo, comparar a efici?ncia de tr?s formas de glifosato: purificado, previamente complexado com metais, e uma das suas formas comerciais (Roundup WG?). Os efeitos de complexos de glifosato com cobre, cobalto e n?quel, sintetizados sob diferentes estequiometrias e valores de pH, foram avaliados sobre a atividade in vitro de EPSPs. Os complexos selecionados para o primeiro experimento in vivo foram: Cu421 e Co821 (primeiro n?mero referente ao pH e os dois ?ltimos ? estequiometria glifosato:metal). Estes complexos foram usados no experimento in vivo I, assim como ?gua destilada (controle), Roundup e glifosato purificado, sobre soja transg?nica e Brachiaria decumbens. Nos experimentos seguintes utilizou-se ?leo mineral em todos os tratamentos para reduzir a lixivia??o dos compostos. O complexo selecionado para continua??o deste estudo foi o Cu421 devido a seu destaque nos resultados obtidos no primeiro experimento in vivo. Ao comparar o efeito dos compostos no ?ndice de Clorofila Falker (ICF) de B. decumbens em rela??o ao controle, observou-se queda deste ?ndice ao usar Roundup, Cu421 e glifosato purificado (este ?ltimo, somente no segundo experimento). Posteriormente foi analisado ac?mulo de massa fresca e coletado material fresco para determina??o das atividades enzim?ticas e dos teores N-NO3-. O complexo Cu421 foi o que provocou maior redu??o da massa fresca e ainda possibilitou o aumento no teor sol?vel de nitrato em B. decumbens, provavelmente devido ? presen?a de nitrato neste complexo. No caso da soja transg?nica n?o houve altera??o significativa de ICF. O uso de Roundup e dos complexos n?o alterou de forma significativa o ac?mulo de massa fresca nesta esp?cie. A aplica??o do glifosato purificado, entretanto, causou incremento no ac?mulo de massa e todos os tratamentos alteraram o teor de nitrato em soja. Nos experimentos com ?leo mineral em B. decumbens, o complexo Cu421 inibiu de forma significativa a atividade de EPSPs, assim como Roundup e glifosato purificado (este ?ltimo, somente no experimento III). Em soja transg?nica n?o houve inibi??o. Todos os tratamentos in vivo estimularam a atividade de PAL somente na gram?nea, permitindo sugerir que o aumento nesta atividade seja consequ?ncia da inibi??o de EPSPs e de outros efeitos delet?rios dos compostos sobre plantas suscept?veis. O presente estudo mostrou que principalmente o complexo Cu421 pode vir a ser utilizado de forma eficaz como herbicida, uma vez que inibe a EPSPs, ativa a PAL, reduz ac?mulo de massa fresca e influencia a fotoss?ntese na planta daninha testada. E, em contrapartida, a soja transg?nica mostrou-se pouco sens?vel a este composto, o que aumenta ainda mais a perspectiva do uso do mesmo como herbicida.
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