3,385 research outputs found
Characterization of adult rat astrocyte cultures
Astrocytes, a major class of glial cells, regulate neurotransmitter systems, synaptic processing, ion homeostasis, antioxidant defenses and energy metabolism. Astrocyte cultures derived from rodent brains have been extensively used to characterize astrocytes’ biochemical, pharmacological and morphological properties. The aims of this study were to develop a protocol for routine preparation and to characterize a primary astrocyte culture from the brains of adult (90 days old) Wistar rats. For this we used enzymatic digestion (trypsin and papain) and mechanical dissociation. Medium exchange occurred from 24 h after obtaining a culture and after, twice a week up to reach the confluence (around the 4th to 5th week). Under basal conditions, adult astrocytes presented a polygonal to fusiform and flat morphology. Furthermore, approximately 95% the cells were positive for the main glial markers, including GFAP, glutamate transporters, glutamine synthetase and S100B. Moreover, the astrocytes were able to take up glucose and glutamate. Adult astrocytes were also able to respond to acute H2O2 exposure, which led to an increase in reactive oxygen species (ROS) levels and a decrease in glutamate uptake. The antioxidant compound resveratrol was able to protect adult astrocytes from oxidative damage. A response of adult astrocytes to an inflammatory stimulus with LPS was also observed. Changes in the actin cytoskeleton were induced in stimulated astrocytes, most likely by a mechanism dependent on MAPK and Rho A signaling pathways. Taken together, these findings indicate that the culture model described in this study exhibits the biochemical and physiological properties of astrocytes and may be useful for elucidating the mechanisms related to the adult brain, exploring changes between neonatal and adult astrocytes, as well as investigating compounds involved in cytotoxicity and cytoprotection
Aplicações ricas para Internet: proposta de Arquitetura de software na nuvem para atender ao Agronegócio
A UNILA, a Prefeitura Municipal de Foz do Iguaçu, a Alfândega da Receita Federal em Foz do Iguaçu, a Universidade Estadual do Oeste do Paraná (Unioeste) e o Instituto Federal do Paraná (IFPR) promoverão conjuntamente, este ano, a Semana Integrada do Servidor Público. O evento pretende ser um espaço de análise e discussão sobre o tema “Valorização e integração: contribuições e desafios do servidor público na atualidade”. As atividades serão realizadas entre os dias 22 e 27 de outubro. O lançamento da Semana foi realizado nesta segunda-feira (27), no auditório da UnioesteEste trabalho é uma proposta de solução para os problemas dos elevados custos em
infraestrutura de Tecnologia da Informação (TI) e de baixa usabilidade das aplicações de
software para monitoramento do agronegócio sendo voltado para profissionais da área de
TI que buscam uma arquitetura de software que proveja uma interface rica e amigável ao
usuário e ainda forneça os benefícios de estar hospedada na nuvem. No decorrer do
trabalho é apresentado as boas práticas para projetar uma arquitetura de software para
aplicação rica da internet na nuvem e os recursos providos pela especificação Java
Enterprise Edition (JEE) que podem ser usados para obter uma aplicação de alto
desempenho e várias tecnologias disponíveis para criar uma aplicação rica quando
utilizamos Java. É abordado ainda as formas adequadas de se projetar uma arquitetura
de software tais como uso de padrões de projetos, divisão da arquitetura em camadas e
reutilização de códigos por meio de classes genéricas. Este trabalho é recomendado para
quem deseja reduzir custos com aplicações we
Rendimiento de las herramientas de metal duro ISO P e ISO S en el torneado de AISI 4140 endurecido en condiciones seco y con MQL
The literature review shows few studies concerning the turning of hardened steels using carbide tools. A research in this case can provide a better understanding and an option of inserts with less cost than usually applied ceramic and CBN (cubic boron nitride) inserts. Thus, the objective is to investigate the tool-life of ISO P and ISO S grade coated carbide inserts and average roughness (Ra) of the machined surface generated with these tools in the hard turning of AISI 4140 steel under dry and minimum-quantity of lubrication (MQL) conditions. Comparing the ISO P and ISO S grades tool life in two different cutting speed levels (60 and 120 m/min), the higher cutting speed generated the lowest Ra values. Relating the lubri-cooling conditions, dry turning resulted in lower Ra values. When the tool nose wear does not change during the passes, the Ra remains constant. In addition, ISO S grade coated carbide insert has shown a possibility for this hard turning due to the low tool nose wear at a relatively high cutting speed.La revisión de la literatura muestra que existen pocos estudios sobre el torneado de los aceros endurecidos utilizando herramientas de metal duro. Una investigación en este caso puede proporcionar una mejor comprensión y la opción de reducir costo es usando los insertos de cerámica y CBN (nitruro de boro cúbico). Por tanto, el objetivo es investigar la vida útil de insertos de metal duro con recubrimiento calidades ISO P e ISO S y la rugosidad media (Ra) de la superficie mecanizada con estas herramientas en el torneado duro del acero AISI 4140 en las condiciones en seco y con una cantidad mínima de lubricante (MQL). En la comparación de la vida de las herramientas ISO P e ISO S en dos niveles de velocidades de corte (60 y 120 m/min), para la mayor velocidad de corte se generaron los valores más bajos de Ra. Al relacionar las condiciones de lubri-refrigeración, los valores más bajos de Ra resultaron con el torneado en seco. Cuando el desgaste de la punta de la herramienta no cambia durante los pases, el valor de Ra permanece constante. Además, el inserto de metal duro con recubrimiento calidad ISO S ha mostrado la posibilidad de usar en el torneado duro debido al bajo desgaste de la punta de la herramienta en una velocidad de corte relativamente alta
Multi-objective optimization of cutting parameters for finishing end milling Hardox® 450
Hardox®450 is pre-hardened structural steel with high hardness and mechanical strength, designed to resist under abrasion wear, cracks, and breakages. This material provides a longer service life for crushers, buckets, and gears due to its excellent mechanical properties, which result in low machinability. Moreover, the knowledge about machining this material is limited, justifying further investigation. Thus, this study aims to evaluate the influence of cutting speed (vc), axial depth of cut (ap), and feed per tooth (fz) on the machining forces and surface finish during the finishing end milling of Hardox®450 with a CVD-coated carbide tool. The experiment was planned and analyzed through a 3-factor, 3-level Box-Behnken Design. The analysis of variance showed that apwas the most significant parameter for all response variables considered in this study. A multiobjectiveoptimization was carried out to determine the ideal levels of cutting parameters, considering the lowest values of static and dynamic machining forces and average and total surface roughnesses. The model suggests that the best results are achieved with vc=89m/min, fz=0.1mm/tooth, and ap=0.212 mm.Even with efficient results, the predicted and measured response variables differed slightly (mainly due to tool wear)
MIGRAÇÃO DE TRABALHADORES NORDESTINOS A PARAUAPEBAS
Este artigo tem o objetivo de apresentar e discutir as relações de produção e trabalho carreadas a partir da migração de nordestinos rumo ao município de Parauapebas, no sudeste do Estado do Pará, os quais compõem significativamente pelo menos 70 mil atores sociais na dinâmica do território em questão, 60% deles como mão de obra em potencial. É possível entender como diferentes concepções de desenvolvimento na região e para a região amazônica, que historicamente é alvo de cobiça e marcada por conflitos, culminam na produção e na circulação do processo de acumulação capitalista, sem as quais haveria uma lacuna no elo entre as diversas instâncias que propiciam a migração de trabalhadores nordestinos em busca de emprego e de melhores condições de vida e seus respectivos papéis na divisão social e territorial do trabalho
Lei Aldir Blanc, política cultural imaterial e folia de reis em Santa Helena de Minas (MG)
The present study has as background the field of the immaterial Brazilian cultural heritage is expanding. Therefore, the article aims to analyze the impacts of the Aldir Blanc Law on immaterial cultural policy from one case: the promotion of a genealogical and socioanthropological research project of the Folia de Reis de Santa Helena de Minas. To this end, a methodology based on ethnography, interviews, analyses of documents and posts on social networks was mobilized. Based on a historical and socio-anthropological perspective, it was highlighted that the impacts were many, some unexpected and/or unplanned caused. So there has been a decentralisation of policies and resources. It is concluded, from the case analyzed, that the unexpected effects of the impact of the Law of this cultural policy could in future help to promote, safeguard and inventory Folia as a regional (and/or national) Brazilian cultural heritage.O presente estudo tem como pano de fundo o campo do patrimônio cultural brasileiro imaterial se encontra em expansão. Logo, o artigo tem por objetivo analisar os impactos da Lei Aldir Blanc na política cultural imaterial a partir de um caso: o fomento de um projeto de pesquisa genealógica e socioantropológica da Folia de Reis de Santa Helena de Minas. Para tanto foi mobilizada uma metodologia pautada na etnografia, em entrevistas, analises de documentos e de postagens em redes sociais. Com base numa perspectiva histórica e socioantropológica, destacou-se que os impactos foram muitos, alguns não esperados e/ou não planejados causados. Assim, houve uma descentralização das políticas e recursos. Conclui-se, a partir do caso analisado, que os efeitos não esperados do impacto da Lei dessa política cultural poderiam futuramente ajudar a promover, salvaguardar e inventariar a Folia como um patrimônio cultural regional (e/ou nacional) brasileiro
SAMBA: Stochastic Analytical Model with a Bayesian Approach
We develop and estimate a DSGE model for the Brazilian economy, to be used as part of the macroeconomic modeling framework at the Central Bank of Brazil. The model combines the building blocks of standard DSGE models (e.g., price and wage rigidities and adjustment costs) with the following features that better describe the Brazilian economy: (i) a fiscal authority pursuing an explicit target for the primary surplus; (ii) administered or regulated prices as part of consumer prices; (iii) external finance for imports, amplifying the effects of changes in external financial conditions on the economy; and (iv) imported goods used in the production function of differentiated goods. It also includes the presence of financially constrained households. We estimate the model with Bayesian techniques, using data starting in 1999, when inflation targeting was implemented. Model evaluation, based on impulse response functions, moment conditions, variance error decomposition and initial forecasting exercises, suggests that the model can be a useful tool for policy analysis and forecasting.
Information system of primary care: integrative review of literature
Objectives: To identify the scientific production on the Information System of Primary Care - SIAB, and critically analyze the scientific production outlining the themes relevant to their applicability to the service. Method: exploratory research descriptive, qualitative approach. The literature review was performed by the Virtual Health Library (VHL) in databases BDENF, SCIELO and LILACS. The descriptors used were: Information System, Primary Health and Family Health. We selected seven potential bibliographies. Results: After reading the articles revealed three categories: SIAB as a tool in the planning of health actions with primary care, use of SIAB professionals in primary health care, the difficulty of completing the farm SIAB. Conclusion: it was discovered the difficulty of understanding the relevance of the data, since they are not passed to reliably records information system, in spite of health professionals and community health workers know their importance
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