95 research outputs found
Redes em Ciência da Informação: evidências comportamentais dos pesquisadores e tendências evolutivas das redes de coautoria
The analysis of complex networks, in special of
the social networks, has being of interest to the
scientific community worldwide. Such interest is
due to its ability to represent complex problems
in an objective manner, allowing for a theoretical
and practical framework to study the characteristics,
properties and behavior of the elements
composing the problems. In the field of
Information Science, techniques of Social Network
Analysis have being used to analyze the
information flow inside communities as well as
the structure of scientific collaboration networks.
However, evolutional aspects that could
be help to predict the behavior of the authors
and, consequently, of the future structure have
been neglected. It is possible to compare Social
Network Analysis, disregarding its evolutional
aspect, with a photograph, which is naturally
static. Despite its importance, the photograph
cannot be so rich in details as a motion
picture, whose temporal elements ease the
context analysis and the construction of predicting
scenarios. This paper evidences the behavior
of researchers in the Information Science’s
field in Brazil, appealing to the evolutional
analysis of the coauthor network, forecasting
impacts on the structure of such networks in
the next few years
A geografia da produção de novos conhecimentos: A dinâmica do ‘quarteto científico’ no Brasil, 2000 a 2010
A literatura que analisa a distribuição espacial da produção científica e tecnológica no Brasil identifica que as diferenças na distribuição regional dos recursos científicos e tecnológicos são muito acentuadas no país. Este artigo visa contribuir para a discussão nessa órbita, analisando a dinâmica da evolução da produção de novos conhecimentos nos estados que mais contribuem para a produção científica nacional, a saber, São Paulo, Rio de Janeiro, Minas Gerais e Rio Grande do Sul (‘quarteto científico’) no período 2000 a 2010. Para tanto, foram realizadas tabulações de informações referentes a variáveis de resultado (produção bibliográfica) destes quatro estados no Diretório dos Grupos de Pesquisa no Brasil do Conselho Nacional de Desenvolvimento Científico e Tecnológico (DGP/CNPq). A hipótese específica desse trabalho é que, mesmo com políticas federais que visam à ampliação e à desconcentração da produção de novos conhecimentos, a sua produção está ainda fortemente ancorada no ‘quarteto’ em toda década dos 2000. Um dos principais resultados deste trabalho é a confirmação dessa hipótese, ao mesmo tempo em que é observada uma pequena desconcentração dessa produção de conhecimentos em direção tanto aos estados menos produtivos dentro do ‘quarteto’, quanto em direção ao restante do país. Finalmente, é identificada também uma concentração dessa produção científica em três grandes áreas do conhecimento (ciências agrárias, biológicas e da saúde), o que caracteriza uma extensão da hipótese proposta
Testosterone represses ubiquitin ligases atrogin-1 and Murf-1 expression in an androgen-sensitive rat skeletal muscle in vivo
Pires-Oliveira M, Maragno AL, Parreiras-E-Silva LT, Chiavegatti T, Gomes MD, Godinho RO. Testosterone represses ubiquitin ligases atrogin-1 and Murf-1 expression in an androgen-sensitive rat skeletal muscle in vivo. J Appl Physiol 108: 266-273, 2010. First published November 19, 2009; doi:10.1152/japplphysiol.00490.2009.-Skeletal muscle atrophy induced by denervation and metabolic diseases has been associated with increased ubiquitin ligase expression. in the present study, we evaluate the influence of androgens on muscle ubiquitin ligases atrogin-1/MAFbx/FBXO32 and Murf-1/Trim63 expression and its correlation with maintenance of muscle mass by using the testosterone-dependent fast-twitch levator ani muscle (LA) from normal or castrated adult male Wistar rats. Gene expression was determined by qRT-PCR and/or immunoblotting. Castration induced progressive loss of LA mass (30% of control, 90 days) and an exponential decrease of LA cytoplasm-to-nucleus ratio (nuclear domain; 22% of control after 60 days). Testosterone deprivation induced a 31-fold increase in LA atrogin-1 mRNA and an 18-fold increase in Murf-1 mRNA detected after 2 and 7 days of castration, respectively. Acute (24 h) testosterone administration fully repressed atrogin-1 and Murf-1 mRNA expression to control levels. Atrogin-1 protein was also increased by castration up to 170% after 30 days. Testosterone administration for 7 days restored atrogin-1 protein to control levels. in addition to the well known stimulus of protein synthesis, our results show that testosterone maintains muscle mass by repressing ubiquitin ligases, indicating that inhibition of ubiquitin-proteasome catabolic system is critical for trophic action of androgens in skeletal muscle. Besides, since neither castration nor androgen treatment had any effect on weight or ubiquitin ligases mRNA levels of extensor digitorum longus muscle, a fast-twitch muscle with low androgen sensitivity, our study shows that perineal muscle LA is a suitable in vivo model to evaluate regulation of muscle proteolysis, closely resembling human muscle responsiveness to androgens.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo, Dept Pharmacol, BR-04044020 São Paulo, BrazilUniv São Paulo, Fac Med Ribeirao Preto, Dept Biochem & Immunol, Ribeirao Preto, BrazilUniversidade Federal de São Paulo, Dept Pharmacol, BR-04044020 São Paulo, BrazilFAPESP: 05/59006-1FAPESP: 2006/58629-8Web of Scienc
Visualization of Information and Visual Methods as Strategic Tools to Project Management
O gerenciamento de projetos tem possibilitado melhores resultados e vantagem competitiva nas organizações. Os projetos, geralmente, são alimentados por uma vasta quantidade de informações que necessitam ser analisadas e seus significados extraídos para a solução de problemas. Manter um gerenciamento adequado e sistemático não é uma tarefa fácil execução e, muitas vezes, se torna uma barreira. Nessa perspectiva, surgem os métodos visuais e a visualização da informação como ferramentas estratégicas para mitigarem os problemas do gerenciamento de projetos. Por meio de métodos visuais e da visualização, as informações são descobertas e explicitadas, a equipe é coordenada e o volume de informações é tratado substancialmente. O objetivo desse estudo é analisar a influência dos métodos visuais e da visualização da informação nos fatores de gerenciamento de projetos: comunicação, demandas (restrições) e ciclo de vida. Com uma pesquisa descritiva e quantitativa, foi aplicado um questionário semiestruturado com escala do tipo likert, composto por cinco variáveis: ciclo de vida, demandas do projeto, comunicação, visualização da informação e métodos visuais. Foram aplicados 386 questionários a alunos de Pós-Graduação Lato Sensu em Gerenciamento de Projetos, Stricto Sensu em Sistemas de Informações e profissionais da área. Obteve-se 359 respondentes válidos e verificou-se que há o reconhecimento da importância dos métodos visuais e visualização da informação no gerenciamento do projeto, além da existência de relações incipientes.Project management offers better results and competitive possibilities in organizations. Projects are usually fed by a vast amount of information that needs to be analyzed for problem solving. Maintaining proper and systematic management is not a simple task and is often a barrier. From this perspective, visual methods and a vision of information appear as strategic tools to mitigate the problems of project management. Through visual and informational methods, as information is discovered and made explicit, a team of coordination and volume of information are substantially treated. The objective of the study is to analyze the influence of visual methods and information visualization on project management factors: communication, demands (restrictions) and life cycle. Through a descriptive and quantitative research, a semi structured questionnaire with a likert-like scale was applied, composed of five variables: life cycle, project demands, communication, information visualization and visual methods. 386 questionnaires were applied to MBA students in Project Management, graduate students in Information Systems and professionals in the area. Were obtained 359 valid respondents and we verify that there is recognition of the importance of visual methods and information without project management
CARACTERÍSTICAS DA INTERAÇÃO ENTRE UNIVERSIDADES/INSTITUTOS PÚBLICOS DE PESQUISA (IPPS) E EMPRESAS EM MINAS GERAIS SOB A PERSPECTIVA DE AMBOS OS AGENTES DO SISTEMA ESTADUAL DE INOVAÇÃO: NOTAS INTRODUTÓRIAS
Staff Knowledge and Attitudes Towards COVID-19 New Biosafety Practices at a Brazilian Dental School
Objective: To evaluate knowledge and attitudes towards biosafety recommendations during the COVID-19 pandemic at a Brazilian dental school. Material and Methods: A cross-sectional study was performed in 2020 with the clinical staff of a Brazilian dental school. The whole clinical staff was sent pre-tested self-administered online questionnaires about knowledge and attitudes towards the recommendations for biosafety in dental settings in the context of the COVID-19 pandemic. Descriptive statistical analyses were carried out for proportion calculation. Results: Disposable head covering caps, isolation gowns, and gloves were the most frequently reported personal protective equipment (PPE). The rates ranged from 52.9% to 88.5% for N95 respirators, from 68.6% to 92.6% for face shields, from 47.4% to 67.5% for conventional eye protection shields, and 45.1% to 77.4% for eye protection with solid side shields. Chlorhexidine gluconate was the most frequent mouthwash indicated before clinical dental care. The percentage of agreement to provide clinical care to patients with suspected COVID-19 varied from 23.5% to 50.0%. The percentage of respondents who agreed that bioaerosol-generating procedures should be avoided was higher than 74.5%. Less than 50% knew the correct sequence for doffing of PPE. Conclusion: This study revealed important gaps in knowledge and attitudes towards prevention and control measures against infection in dental environments in the context of COVID-19, indicating the need for improvements
Mapping agricultural intensification in the Brazilian savanna: a machine learning approach using harmonized data from Landsat Sentinel-2.
Agricultural intensification practices have been adopted in the Brazilian savanna (Cerrado), mainly in the transition between Cerrado and the Amazon Forest, to increase productivity while reducing pressure for new land clearing. Due to the growing demand for more sustainable practices, more accurate information on geospatial monitoring is required. Remote sensing products and artificial intelligence models for pixel-by-pixel classification have great potential. Therefore, we developed a methodological framework with spectral indices (Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), and Soil-Adjusted Vegetation Index (SAVI)) derived from the Harmonized Landsat Sentinel-2 (HLS) and machine learning algorithms (Random Forest (RF), Artificial Neural Networks (ANNs), and Extreme Gradient Boosting (XGBoost)) to map agricultural intensification considering three hierarchical levels, i.e., temporary crops (level 1), the number of crop cycles (level 2), and the crop types from the second season in double-crop systems (level 3) in the 2021-2022 crop growing season in the municipality of Sorriso, Mato Grosso State, Brazil. All models were statistically similar, with an overall accuracy between 85 and 99%. The NDVI was the most suitable index for discriminating cultures at all hierarchical levels. The RF-NDVI combination mapped best at level 1, while at levels 2 and 3, the best model was XGBoost-NDVI. Our results indicate the great potential of combining HLS data and machine learning to provide accurate geospatial information for decision-makers in monitoring agricultural intensification, with an aim toward the sustainable development of agriculture
A interação universidades/institutos públicos de pesquisa e empresas no Brasil: resultados comparativos entre o relacionamento com empresas nacionais e multinacionais
O objetivo deste artigo é investigar os padrões de interação de empresas nacionais e multinacionais localizadas no Brasil com universidades/institutospúblicos de pesquisa (IPPs) presentes no país. Para tanto, utilizou-se uma base de dados que envolve 319 questionários respondidos pelos responsáveis pelas atividades de pesquisa e desenvolvimento (P&D) e/ou pelas interações com universidades e IPPs em empresas localizadas no Brasil, as quais apresentavam interação com grupos de pesquisa sediados em universidades/IPPs brasileiros no ano de 2004.Tais informações foram avaliadas por meio de uma análise descritiva dos dados para verificar a existência de padrões distintos de interação universidade-empresapara empresas nacionais e multinacionais. As conclusões do trabalho sugerem que não existem diferenças significativas entre os padrões de cooperação de empresas nacionais e empresas multinacionais com universidades/IPPs brasileiros.The Brazilian industry & university/public research institutes’s interaction: comparative relashionship evidence between domestic and multinational companiesAbstract: The aim of this paper is to investigate the interaction patterns of national and multinational enterprises located in Brazil with universities/public research institutes (PRIs) in the country. To this end, we used a database involving 319 questionnaires answered by those responsible for the activities of research and development (R & D) and/or by interactions with universities and PRIs in enterprises located in Brazil, which interacted with research groups of Brazilian universities or PRIs in 2004. Such data were evaluated through a descriptive analysis to verify the existence of distinct patterns of university-industry interactions concerning national and multinationalenterprises. The conclusions of the study suggest that there are not significant differences between the cooperation patterns of national and multinational companies with Brazilian universities/PRIs.Key-words: multinational enterprises; national enterprises; university/industry interactions.JEL: L29; O10; O30
Hydrogen peroxide production regulates the mitochondrial function in insulin resistant muscle cells: Effect of catalase overexpression
AbstractThe mitochondrial redox state plays a central role in the link between mitochondrial overloading and insulin resistance. However, the mechanism by which the ROS induce insulin resistance in skeletal muscle cells is not completely understood. We examined the association between mitochondrial function and H2O2 production in insulin resistant cells. Our hypothesis is that the low mitochondrial oxygen consumption leads to elevated ROS production by a mechanism associated with reduced PGC1α transcription and low content of phosphorylated CREB. The cells were transfected with either the encoded sequence for catalase overexpression or the specific siRNA for catalase inhibition. After transfection, myotubes were incubated with palmitic acid (500μM) and the insulin response, as well as mitochondrial function and fatty acid metabolism, was determined. The low mitochondrial oxygen consumption led to elevated ROS production by a mechanism associated with β-oxidation of fatty acids. Rotenone was observed to reduce the ratio of ROS production. The elevated H2O2 production markedly decreased the PGC1α transcription, an effect that was accompanied by a reduced phosphorylation of Akt and CREB. The catalase transfection prevented the reduction in the phosphorylated level of Akt and upregulated the levels of phosphorylated CREB. The mitochondrial function was elevated and H2O2 production reduced, thus increasing the insulin sensitivity. The catalase overexpression improved mitochondrial respiration protecting the cells from fatty acid-induced, insulin resistance. This effect indicates that control of hydrogen peroxide production regulates the mitochondrial respiration preventing the insulin resistance in skeletal muscle cells by a mechanism associated with CREB phosphorylation and β-oxidation of fatty acids
Padronização da titulação da toxina épsilon de Clostridium perfringens tipo D em linhagem contínua de células como alternativa ao bioensaio animal
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