83 resultados para SLP
Resumo:
The results demonstrate that Gads plays a key role in linking the adapter LAT to SLP-76 in response to weak activation of GPVI and CLEC-2 whereas LAT is required for full activation over a wider range of agonist concentrations. These results reveal the presence of a Gads-independent pathway of platelet activation downstream of LAT.
Resumo:
GPVI activates platelets through an ITAM pathway by activation of Src and Syk kinases leading to activation of PLCy2. CLEC-2 has been shown to activate platelets using an ITAM-like sequence in its cytoplasmic tail that is also dependent on Src and Syk kinases, but shows a partial rather than an absolute dependence on adapter SLP-76 for activation of PLCy2. The aim of this thesis is to understand some of the key differences in these signalling pathways. GPVI is in complex with FcRwhich contains the ITAM sequence (Yxx(L/I)x6−12Yxx(L/I)). These two tyrosines provide a docking site for the tandem-SH2 domains of Syk. In this thesis I show that CLEC-2 signalling through Syk is mediated by phosphorylation of the CLEC-2 YxxL sequence, receptor dimerisation and cross-linking by the Syk SH2 domains. I also show that the differential requirement for SLP-76 is not mediated by Gads. Both signalling pathways also show partial dependency for LAT. I also show that a novel protein, G6f, is not able to substitute for LAT in this signalling pathway and also exclude the LAT-family proteins PAG, LIME, LAX and NTAL as potential LAT replacements in platelet activation by GPVI. These results extend our understanding of platelet activation by CLEC-2.
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Variability and trends in seasonal and interannual ice area export out of the Laptev Sea between 1992 and 2011 are investigated using satellite-based sea ice drift and concentration data. We found an average total winter (Octo- ber to May) ice area transport across the northern and east- ern Laptev Sea boundaries (NB and EB) of 3.48 × 10 5 km 2 . The average transport across the NB (2.87 × 10 5 km 2 ) is thereby higher than across the EB (0.61 × 10 5 km 2 ), with a less pronounced seasonal cycle. The total Laptev Sea ice area flux significantly increased over the last decades (0.85 × 10 5 km 2 decade − 1 , p> 0 . 95), dominated by increas- ing export through the EB (0.55 × 10 5 km 2 decade − 1 , p> 0 . 90), while the increase in export across the NB is smaller (0.3 × 10 5 km 2 decade − 1 ) and statistically not significant. The strong coupling between across-boundary SLP gradient and ice drift velocity indicates that monthly variations in ice area flux are primarily controlled by changes in geostrophic wind velocities, although the Laptev Sea ice circulation shows no clear relationship with large-scale atmospheric in- dices. Also there is no evidence of increasing wind velocities that could explain the overall positive trends in ice export. The increased transport rates are rather the consequence of a changing ice cover such as thinning and/or a decrease in con- centration. The use of a back-propagation method revealed that most of the ice that is incorporated into the Transpolar Drift is formed during freeze-up and originates from the cen- tral and western part of the Laptev Sea, while the exchange with the East Siberian Sea is dominated by ice coming from the central and southeastern Laptev Sea. Furthermore, our re- sults imply that years of high ice export in late winter (Febru- ary to May) have a thinning effect on the ice cover, which in turn preconditions the occurence of negative sea ice extent anomalies in summer.
Resumo:
This study analyzes and discusses data taken from oceanic and atmospheric measurements performed simultaneously at the Brazil-Malvinas Confluence (BMC) region in the southwestern Atlantic Ocean. This area is one of the most dynamical frontal regions of the world ocean. Data were collected during four research cruises in the region once a year in consecutive years between 2004 and 2007. Very few studies have addressed the importance of studying the air-sea coupling at the BMC region. Lateral temperature gradients at the study region were as high as 0.3 degrees C km(-1) at the surface and subsurface. In the oceanic boundary layer, the vertical temperature gradient reached 0.08 degrees C m(-1) at 500 m depth. Our results show that the marine atmospheric boundary layer (MABL) at the BMC region is modulated by the strong sea surface temperature (SST) gradients present at the sea surface. The mean MABL structure is thicker over the warmside of the BMC where Brazil Current (BC) waters predominate. The opposite occurs over the coldside of the confluence where waters from the Malvinas (Falkland) Current (MC) are found. The warmside of the confluence presented systematically higher MABL top height compared to the coldside. This type of modulation at the synoptic scale is consistent to what happens in other frontal regions of the world ocean, where the MABL adjusts itself to modifications along the SST gradients. Over warm waters at the BMC region, the MABL static instability and turbulence were increased while winds at the lower portion of the MABL were strong. Over the coldside of the BC/MC front an opposite behavior is found: the MABL is thinner and more stable. Our results suggest that the sea-level pressure (SLP) was also modulated locally, together with static stability vertical mixing mechanism, by the surface condition during all cruises. SST gradients at the BMC region modulate the synoptic atmospheric pressure gradient. Postfrontal and prefrontal conditions produce opposite thermal advections in the MABL that lead to different pressure intensification patterns across the confluence.
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Este trabalho é uma contribuição para o conhecimento de metodologias de projeto de estruturas de material composto, aplicando métodos de otimização estrutural a cascas laminadas e apresentando uma estratégia em dois níveis. No primeiro nível é realizada a minimização da flexibilidade da estrutura, tendo como variável de projeto a orientação de cada lâmina da estrutura. Utiliza-se Programação Linear Seqüencial (SLP) e direção de tensão principal para otimização da orientação. No segundo nível minimiza-se o volume de cada lâmina, usando a flexibilidade total da estrutura como restrição e a densidade relativa como variável de projeto, também através de SLP. Para evitar aparecimento de áreas com densidades intermediárias, utiliza-se um Método de Continuação, dividindo o nível de otimização topológica em duas ou mais etapas. As formulações desenvolvidas permitem a solução de problemas com múltiplos casos de carregamento. Para a solução da equação de equilíbrio de casca laminada, utiliza-se um elemento finito de casca degenerado de oito nós com integração explícita na direção da espessura. A implementação desse elemento é feita de modo a facilitar a obtenção das derivadas da matriz de rigidez, necessárias na linearização das funções objetivo e restrições. Evita-se assim o uso de derivadas numéricas. Resultados para vários tipos de estrutura são apresentados, incluindo comparações entre diferentes carregamentos, condições de contorno, número de lâminas, espessuras, etc. As soluções obtidas, formas de análise e possíveis aplicações são discutidas.
Resumo:
Este estudo teve como objetivo avaliar se o Sistema de Gestão Logística e Patrimonial (SLP) desenvolvido pela Administração Nacional do SESC, atende às necessidades de suas Administrações Regionais, apontando elementos positivos e negativos. Envolvendo as áreas de logística de suprimentos, logística interna e gestão de bens móveis pennanentes, o estudo teve também como objetivo estabelecer metodologia de avaliação, visto que não se encontrou caso similar aplicado em organizações prestadoras de serviços. A metodologia tratou de aspectos gerais relacionados a maior significância das atividades de recursos humanos, a eficiência das tarefas e a qualidade e segurança das infonnações, tudo resultado da utilização de tecnologia de infonnação. De fonna mais específica, a metodologia tratou de pontos focais das áreas que compõem o estudo: infonnação, cadastro, processamento, monitoramento, recebimento e planejamento. Incluiu-se ainda no método, avaliação sobre a necessidade de desenvolvimento de módulo de logística de distribuição no SLP. Os resultados do estudo evidenciaram que o SLP atende às necessidades das Administrações Regionais do SESC, que a necessidade de desenvolvimento do módulo de logística de distribuição deve ser melhor analisada e que a metodologia se mostrou viável e deve ser motivo de novas pesquisas em organizações prestadoras de serviços, inclusive no SESC, visto que o modelo gera impactos no gerenciamento da atividade logística e patrimonial.
Resumo:
A aplicação de técnicas para o desenvolvimento de soluções para problemas existentes dentro dos setores produtivos tornam-se cada vez mais necessária, devido às constantes modificações tecnológicas, econômicas e sociais experimentadas pelas empresas. Dentre essas técnicas destaca-se o SLP (Systematic Layout Planning - Planejamento Sistemático de Layout), que traz resultados positivos na reestuturação de layouts fabris. No presente trabalho, apresentam-se diferentes opções de layouts, suas aplicações, vantagens e desvantagens, bem como sua utilização no contexto do SLP. Para tanto, realizou-se um estudo de caso utilizando o SLP Planejamento Sistemático de Layout em setor de pintura do ramo metal-mecânico. Os resultados obtidos revelam-se através do re-arranjo de postos de trabalho com redução no fluxo de linha de acordo com a aproximação de postos por afinidades e um melhor controle de produção, através de um melhor seqüênciamento da linha. Essa alteração também possibilitou uma melhor organização espacial dos pontos de trabalho e um incremento da capacidade produtiva dentro da empresa. A metologia adotada pode ser utilizada como ferramenta de melhoria nos demais setores, tanto da própria empresa, como de outras que se assemelham ao processo produtivo descrito neste estudo de caso.
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Este trabalho aborda o projeto otimizado de transdutores eletro-mecânicos baseados no fenô- meno da piezeletricidade e submetidos a não-linearidade geométrica. Para este m, é proposta uma formulação de equilíbrio para descrever o movimento nito de um corpo piezelétrico e a sua discretização por meio do método dos Elementos Finitos. Problemas de equilíbrio com pontos limites podem ser corretamente simulados com a abordagem de solução proposta, pois questões como a imposição de comprimento de arco em problemas acoplados são discutidas. Diferentes métodos de controle de arco são discutidos e é proposta a consideração do método dos Deslocamentos Generalizados como um tipo de controle de comprimento de arco da família das restrições ortogonais. A formulação de otimização proposta consiste na maximização de componentes do vetor de estado de alguns pontos da estrutura (portas de saída) com restrição de volume e valores de algumas posições do vetor de estado. A análise de sensibilidade proposta, baseada na abordagem adjunta, é su cientemente geral para permitir o projeto de atuadores e sensores e permite a aplicação de condições de contorno essenciais não-homogêneas, como é o caso da diferença de potencial. O método das Assíntotas Móveis Generalizadas (GMMA) é utilizado conjuntamente com a tradicional Programação Linear Sequencial (SLP) para a solução do problema de otimização e suas implementações são discutidas em detalhes. Resultados mostrando a in uência da não-linearidade geométrica e/ou rigidez externa nãolinear no projeto de transdutores piezelétricos são apresentados e discutidos.
Resumo:
A correta utilização do espaço físico de uma fábrica é fator importante para o seu bom funcionamento, já que estabelece a sua organização fundamental, bem como os padrões de fluxo de materiais e informações, com efeitos que se farão presentes no longo prazo. A fim de sistematizar um adequado planejamento de layout, métodos para planejamento do macro-espaço, como o SLP (Systematic Layout Planning – Planejamento Sistemático de Layout), podem auxiliar no desenvolvimento de alternativas de layout. Contudo, devido à geração de soluções sub-ótimas com benefícios e desvantagens diferentes, o processo decisório da melhor alternativa de layout torna-se crítico para garantir a eficiência e flexibilidade de empresas frente aos diferentes cenários de mercado. O objetivo principal desta dissertação é a utilização de ferramentas de apoio à decisão multicritério em sistemáticas de planejamento de layout. A metodologia de análise multicritério proposta foi colocada em prática na seleção de alternativas de layout em uma empresa do ramo automotivo, que necessita ampliar seu parque fabril de modo a possibilitar a incorporação de novos equipamentos e otimização do fluxo de materiais. Nove alternativas de macro-layout diferentes foram geradas sendo avaliada a melhor alternativa geral em relação a sete critérios de avaliação.
Resumo:
Neospora caninum is a coccidian parasite that causes disease in captive and domesticated animals and has been found in wild animals such as cervids. Sera from 150 cervids of the genus Mazama, were collected from 31 captive herds and 16 zoos from different Brazilian regions and analyzed by indirect fluorescent antibody test for anti-N. caninum antibodies. Positive reactions were found in 42% (63) of the samples and the titers varied from 50 to 51,200. of the 86 cervids from the captive herds, 38 (44.2%) had anti N. caninum antibodies and of the 64 samples from the zoo, 25 (39.1%) were positive. No significant difference (p > 0.05) was found for the occurrence values observed between the animals from captive herds and zoos as well as within the values documented for each one of the species analyzed. Therefore, the results indicate that the agent is prevalent from cervids in captivity in Brazil. (c) 2005 Elsevier B.V. All rights reserved.
Resumo:
Sera obtained from pampas-deer (Ozotoceros bezoarticus) captured in two different Brazilian environments were analyzed for the presence of anti-Neospora caninum antibodies by the indirect fluorescent antibody test (IFAT). Samples were collected from 23 animals from a savanna area in the National Park of Emas, in the state of Goias, Brazil. This area is surrounded by cultivated lands and allows very little contact between wild and domestic animals. Another batch of samples was collected from 16 animals from the Pantanal region, in the state of Mato Grosso, Brazil. This area is a flood plain where domestic animals have intensive contact with cervids. The 39 samples were analyzed (IFAT >= 1:50), and the values for the occurrences found in the animals from each region were compared by the test for comparison of two proportions. of the 39 cervids examined, 38.46% (15) had anti-N. caninum antibodies. Three (13%) of the 23 samples from the National Park of Emas. and 12 (75%) of the 16 samples from the Pantanal were positive, with significant differences between regions (p < 0.001). These results suggested that the presence of domestic animals, mainly dogs and cattle, may be responsible for the greater occurrence of N. caninum in the Pantanal cervids.Thus, as a recommendation of the Conservation Units that care for the pampas-deer, attention should be taken to carefully monitor the flow of diseases between the domestic animals and this species. (c) 2005 Elsevier B.V. All rights reserved.
Resumo:
Nasoendoscopy is an important tool for assessing velopharyngeal function. The purpose of this study was to analyze velar and pharyngeal wall movement and velopharyngeal gap during nasoendoscopic evaluation of the velopharynx before and during diagnostic therapy. Nasoendoscopic recordings of 10 children with operated cleft lip and palate were analyzed according to the International Working Group Guidelines. Ratings of movement of velum and pharyngeal walls, and size, location and shape of gaps were analyzed by 3 speech-language pathologists (SLPs). Imaging was obtained during repetitions of the syllable /pa/ during a single nasoendoscopic evaluation: (a) before diagnostic therapy, and (b) after the children were instructed to impound and increase intraoral air pressure (diagnostic therapy). Once the patients impounded and directed air pressure orally, the displacement of the velum, right, left and posterior pharyngeal walls increased 40, 70, 80, and 10%, respectively. Statistical significance for displacement was found only for right and left lateral pharyngeal walls. Reduction in gap size was observed for 30% of the patients and other 40% of the gaps disappeared. Changes in gap size were found to be statistically significant between the two conditions. In nasoendoscopic assessment, the full potential of velopharyngeal displacement may not be completely elicited when the patient is asked only to repeat a speech stimulus. Optimization of information can be done with the use of diagnostic therapy's strategies to manipulate VP function. Assuring the participation of the SLP to conduct diagnostic therapy is essential for management of velopharyngeal dysfunction.
Resumo:
Software Product Line (SPL) consists of a software development paradigm, whose main focus is to identify features common and variability among applications in a specific domain. An LPS is designed to attend all products requirements from its product family. These requirements and LPS may have changes over time due to several factors, such as evolution of product requirements, evolution of the market, evolution of SLP process, evolution of the technologies used to develop the products. To handle these changes, LPS should be modified and evolve in order to not become obsolete, and adapt itself to new requirements. The Changes Impact Analysis is an activity that understand and identify what consequences these changes are cause on LPS. Impact Analysis on LPS may be supported by traceability relationships, which identify relationships between artefacts created during all phases of software development. Despite the solutions of change impact analysis based on traceability for software, there is a lack of solutions for assessing the change impact analysis based on traceability for LPS, since existing solutions do not include estimates specific to the artefacts of LPS. Thus, this paper proposes a process of change impact analysis and an tool for assessing the change impact through traceability of artefacts in LPS. For this purpose, we specified a process of change impact analysis that considers artifacts produced during the development of LPS. We have also implemented a tool which allows estimating and identifying artefacts and products of LPS affected from changes in other products, changes in class, changes in features, changes between releases of LPS and artefacts related to changes in core assets and variability. Finally, the results were evaluated through metrics
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A combined methodology consisting of successive linear programming (SLP) and a simple genetic algorithm (SGA) solves the reactive planning problem. The problem is divided into operating and planning subproblems; the operating subproblem, which is a nonlinear, ill-conditioned and nonconvex problem, consists of determining the voltage control and the adjustment of reactive sources. The planning subproblem consists of obtaining the optimal reactive source expansion considering operational, economical and physical characteristics of the system. SLP solves the optimal reactive dispatch problem related to real variables, while SGA is used to determine the necessary adjustments of both the binary and discrete variables existing in the modelling problem. Once the set of candidate busbars has been defined, the program implemented gives the location and size of the reactive sources needed, if any, to maintain the operating and security constraints.
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This paper presents the Benders decomposition technique and Branch and Bound algorithm used in the reactive power planning in electric energy systems. The Benders decomposition separates the planning problem into two subproblems: an investment subproblem (master) and the operation subproblem (slave), which are solved alternately. The operation subproblem is solved using a successive linear programming (SLP) algorithm while the investment subproblem, which is an integer linear programming (ILP) problem with discrete variables, is resolved using a Branch and Bound algorithm especially developed to resolve this type of problem.