Mechanical, biochemical, and morphological changes in the heart from chronic food-restricted rats

Food restriction (FR) has been shown to induce important morphological changes in rat myocardium. However, its influence on myocardial performance is not completely defined. We examined the effects of chronic FR on cardiac muscle function and morphology. Sixty-day-old Wistar-Kyoto rats were fed a control (C) or a restricted diet (daily intake reduced to 50% of the amount of food consumed by the control group) for 90 days. Myocardial performance was studied in isolated left ventricular (LV) papillary muscle. Fragments of the LV free wall were analysed by light microscopy, and the ultrastructure of the myocardium was examined in the LV papillary muscle. The myocardial collagen concentration was also evaluated. FR decreased body weight (BW) and LV weight (LVW); the LVW/BW ratio was higher in the restricted group (C, 1.86 +/- 0.17 mg/g; FR, 2.19 +/- 0.31 mg/g; p < 0.01). In the FR animals, the cardiac fibers were polymorphic, some of them were of small diameter and others presented lateral infoldings; the ultrastructural alterations were focal and included reduction of sarcoplasmic content, absence and (or) disorganization of myofilaments and Z line, numerous electron dense and polymorphic mitochondria, and deep infoldings of the plasma membrane. The hydroxyproline concentration was higher in the FR animals (p < 0.01). FR prolonged the contraction and relaxation time of the papillary muscle and did not change its ability to contract and shorten. In conclusion, although a 90-day period of FR caused striking myocardial ultrastructural alterations and increased the collagen concentration, it only minimally affected the mechanical function.

Relativistic Archimedes law for fast moving bodies and the general-relativistic resolution of the submarine paradox

We investigate and solve in the context of general relativity the apparent paradox which appears when bodies floating in a background fluid are set in relativistic motion. Suppose some macroscopic body, say, a submarine designed to lie just in equilibrium when it rests (totally) immersed in a certain background fluid. The puzzle arises when different observers are asked to describe what is expected to happen when the submarine is given some high velocity parallel to the direction of the fluid surface. on the one hand, according to observers at rest with the fluid, the submarine would contract and, thus, sink as a consequence of the density increase. on the other hand, mariners at rest with the submarine using an analogous reasoning for the fluid elements would reach the opposite conclusion. The general relativistic extension of the Archimedes law for moving bodies shows that the submarine sinks. As an extra bonus, this problem suggests a new gedankenexperiment for the generalized second law of thermodynamics.

Diretrizes para implantação de sistemas de segurança e saúde do trabalho em empresas produtoras de baterias automotivas

O desenvolvimento de Sistemas de Gestão da Segurança e Saúde no Trabalho (SGSST) ganha um significado cada vez mais importante no desempenho das empresas, pois, por meio deles, é possível obter a promoção da saúde e satisfação dos trabalhadores e a redução dos riscos de acidentes. No entanto, para que um SGSST obtenha bons resultados, as empresas precisam estar atentas às dificuldades comumente encontradas durante o seu processo de implantação, procurando solucioná-las de maneira antecipada e estruturada. Pelo exposto, este trabalho tem como principal objetivo apresentar diretrizes, baseadas no referencial teórico e nos resultados dos estudos de caso realizados, para implantação de SGSSTs em empresas fabricantes de baterias automotivas. Para o seu desenvolvimento adotou-se o método de pesquisa qualitativa a partir da realização de dois estudos de caso em empresas fabricantes de baterias automotivas localizadas na cidade de Bauru. Os instrumentos de coleta de dados foram entrevistas semiestruturadas, análise de documentos e observação in loco. Ao final do artigo, são propostas diretrizes relacionadas aos seguintes elementos: alta direção, estratégia organizacional, cultura organizacional, departamento de Segurança e Saúde do Trabalho (SST), técnicos de SST, recursos humanos, treinamento, equipes multidisciplinares, comunicação interna, resistência à mudança, indicadores de desempenho, ferramentas gerenciais para solução de problemas de SST, gestão de projetos, recompensas e incentivos, e integração do sistema.

Incidência de acidentes do trabalho não-fatais em localidade do Sudeste do Brasil

Estimou-se a proporção de incidência de acidentes do trabalho na Cidade de Botucatu, São Paulo, Brasil, segundo sexo, idade, existência de contrato de trabalho e ocupações. Para tanto, foi realizado inquérito domiciliar em amostra aleatória sistemática por conglomerados (195 setores censitários). Coletaram-se informações de todos os moradores dos domicílios amostrados com idade maior que nove anos. Para aqueles que trabalhavam nos últimos noventa dias que precederam a entrevista, foram obtidas informações sobre ocupação, posição na ocupação, contrato de trabalho e ocorrência de acidentes. Foram estudados 9.626 domicílios residenciais (fração amostral de 0,26). A proporção de acidentes não-fatais no município foi de 3,3% (IC95%: 2,7-3,9), sendo maior em homens 4,5% (IC95%: 3,6-5,5), variando com o tipo de contrato de trabalho e grande grupo de ocupação. Comparando-se esses resultados com períodos anteriores, observa-se diminuição significativa do risco de acidentes na cidade.

Engaging environments: Tacit knowledge sharing on the shop floor

Purpose: The purpose of this paper is to identify factors that facilitate tacit knowledge sharing in unstructured work environments, such as those found in automated production lines. Design/methodology/approach: The study is based on a qualitative approach, and it draws data from a four-month field study at a blown-molded glass factory. Data collection techniques included interviews, informal conversations and on-site observations, and data were interpreted using content analysis. Findings: The results indicated that sharing of tacit knowledge is facilitated by an engaging environment. An engaging environment is supported by shared language and knowledge, which are developed through intense communication and a strong sense of collegiality and a social climate that is dominated by openness and trust. Other factors that contribute to the creation of an engaging environment include managerial efforts to provide appropriate work conditions and to communicate company goals, and HRM practices such as the provision of formal training, on-the-job training and incentives. Practical implications: This paper clarifies the scope of managerial actions that impact knowledge creation and sharing among blue-collar workers. Originality/value: Despite the acknowledgement of the importance of blue-collar workers' knowledge, both the knowledge management and operations management literatures have devoted limited attention to it. Studies related to knowledge management in unstructured working environments are also not abundant. © Emerald Group Publishing Limited.

Ensino apostilado na escola pública: tendência crescente nos municípios da região de São José do Rio Preto-SP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Implantação de sistemas de segurança e saúde no trabalho em empresas fabricantes de baterias automotivas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Herbert Marcuse: crítico da sociedade tecnocrática

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Vozes paulistas: as práticas do canto coral em São Paulo e suas relações com políticas públicas para a cultura

Pós-graduação em Música - IA

Recuperação da palha da cana-de-açúcar para a produção de energia elétrica e etanol celulósico

Pós-graduação em Engenharia Mecânica - FEIS

Transposição de metros clássicos em língua portuguesa: histórico e estudo do caso das Odes e elegias, de Magalhães de Azeredo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Location and contract pricing of distributed generation using a genetic algorithm

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Bilevel approach for optimal location and contract pricing of distributed generation in radial distribution systems using mixed-integer linear programming

In this study, a novel approach for the optimal location and contract pricing of distributed generation (DG) is presented. Such an approach is designed for a market environment in which the distribution company (DisCo) can buy energy either from the wholesale energy market or from the DG units within its network. The location and contract pricing of DG is determined by the interaction between the DisCo and the owner of the distributed generators. The DisCo intends to minimise the payments incurred in meeting the expected demand, whereas the owner of the DG intends to maximise the profits obtained from the energy sold to the DisCo. This two-agent relationship is modelled in a bilevel scheme. The upper-level optimisation is for determining the allocation and contract prices of the DG units, whereas the lower-level optimisation is for modelling the reaction of the DisCo. The bilevel programming problem is turned into an equivalent single-level mixed-integer linear optimisation problem using duality properties, which is then solved using commercially available software. Results show the robustness and efficiency of the proposed model compared with other existing models. As regards to contract pricing, the proposed approach allowed to find better solutions than those reported in previous works. © The Institution of Engineering and Technology 2013.