994 resultados para Return period
Resumo:
Within the skeletal muscle cell at the onset of muscular contraction, phosphocreatine (PCr) represents the most immediate reserve for the rephosphorylation of adenosine triphosphate (ATP). As a result, its concentration can be reduced to less than 30% of resting levels during intense exercise. As a fall in the level of PCr appears to adversely affect muscle contraction, and therefore power output in a subsequent bout, maximising the rate of PCr resynthesis during a brief recovery period will be of benefit to an athlete involved in activities which demand intermittent exercise. Although this resynthesis process simply involves the rephosphorylation of creatine by aerobically produced ATP (with the release of protons), it has both a fast and slow component, each proceeding at a rate that is controlled by different components of the creatine kinase equilibrium. The initial fast phase appears to proceed at a rate independent of muscle pH. Instead, its rate appears to be controlled by adenosine diphosphate (ADP) levels; either directly through its free cytosolic concentration, or indirectly, through its effect on the free energy of ATP hydrolysis. Once this fast phase of recovery is complete, there is a secondary slower phase that appears almost certainly rate-dependant on the return of the muscle cell to homeostatic intracellular pH. Given the importance of oxidative phosphorylation in this resynthesis process, those individuals with an elevated aerobic power should be able to resynthesise PCr at a more rapid rate than their sedentary counterparts. However, results from studies that have used phosphorus nuclear magnetic resonance (P-31-NMR) spectroscopy, have been somewhat inconsistent with respect to the relationship between aerobic power and PCr recovery following intense exercise. Because of the methodological constraints that appear to have limited a number of these studies, further research in this area is warranted.
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Objectives: The present study describes the natural history of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Prevotella intermedia over a 5-year period and the effect of a triclosan/copolymer dentifrice on these organisms in a normal adult population. Material and Methods: Subgingival plaque samples were collected from 504 adult volunteers. Probing pocket depths (PPD) and relative attachment levels were measured using an automated probe. Participants were matched for disease status (CPI), plaque index, age and gender, and allocated to receive either a triclosan/copolymer or placebo dentifrice. Re-examination and subgingival plaque sampling was repeated after 1, 2, 3, 4 and 5 years. P. gingivalis, A. actinomycetemcomitans and P. intermedia were detected and quantitated using an enzyme linked immunosorbent assay. Logistic regression and generalised linear modelling were used to analyse the data. Results: This 5-year longitudinal study showed considerable volatility in acquisition and loss (below the level of detection) of all three organisms in this population. Relatively few subjects had these organisms on multiple occasions. While P. gingivalis was related to loss of attachment and to PPD greater than or equal to3.5 mm, there was no relationship between A. actinomycetemcomitans or P. intermedia and disease progression over the 5 years of the study. Smokers with P. gingivalis had more PPD greater than or equal to3.5 mm than smokers without this organism. There was no significant effect of the triclosan dentifrice on P. gingivalis or A. actinomycetemcomitans . Subjects using triclosan were more likely to have P. intermedia than those not using the dentifrice; however this did not translate into these subjects having higher levels of P. intermedia and its presence was uniform showing no signs of increasing over the course of the study. Conclusion: The present 5-year longitudinal study has shown the transient nature of colonisation with P. gingivalis , A. actinomycetemcomitans and P. intermedia in a normal adult population. The use of a triclosan-containing dentifrice did not lead to an overgrowth of these organisms. The clinical effect of the dentifrice would appear to be independent of its antimicrobial properties.
Resumo:
Low temperature during panicle development in rice increases spikelet sterility. This effect is exacerbated by high rates of nitrogen (N) application in the field. Spikelet sterility induced by low temperature and N fertilisation was examined in glasshouse experiments to clarify the mechanisms involved. In two glasshouse experiments, 12-h periods of low (18/13degreesC) and high (28/23degreesC) day/night temperatures were imposed over periods of 5-7 days during panicle development, to determine the effects of low temperature and N fertilisation on spikelet sterility. In one experiment, 50% sunlight was imposed together with low temperature to investigate the additive effects of reduced solar radiation and low temperature. The effect of increased tillering due to N fertilisation was examined by a tiller removal treatment in the same experiment. Pollen grain number and spikelet sterility were recorded at heading and harvest, respectively. Although there was no significant effect of low temperature on spikelet sterility in the absence of applied N, low temperature greatly increased spikelet sterility as a result of a reduction in the number of engorged pollen grains per anther in the presence of applied N. Spikelet sterility was strongly correlated with the number of engorged pollen grains per anther. Low temperature during very early ( late stage of spikelet differentiation-pollen mother cell stage) and peak ( second meiotic division stage-early stage of extine formation) microspore development caused a severe reduction in engorged pollen production mainly as a result of reduced total pollen production. Unlike low temperature, the effect of shading was rather small. The increased tillering due to application of high rates of N, increased both spikelet number per plant and spikelet sterility under low temperature conditions. The removal of tillers as they appeared reduced the number of total spikelets per plant and maintained a large number of engorged pollen grains per anther which, in turn, reduced spikelet sterility. The number of engorged pollen grains per anther determined the numbers of intercepted and germinated pollen grains on the stigma. It is concluded that N increased tillering and spikelet number per plant and this, in turn, reduced the number of engorged pollen grains per anther, leading into increased spikelet sterility under low temperature condition.
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O objetivo deste artigo ?? apresentar um modelo alternativo de an??lise da efici??ncia dos programas de p??s-gradua????o acad??micos em Administra????o, Contabilidade e Turismo, vinculados ??s institui????es de ensino superior p??blicas e privadas. O estudo tem como base te??rica a efici??ncia e a otimiza????o de recursos, tomando como refer??ncia a maximiza????o do retorno, sujeito ??s limita????es de recursos. Como modelo anal??tico foi utilizada a An??lise Envolt??ria de Dados (DEA), enquanto t??cnica n??o param??trica de an??lise da efici??ncia relativa. Os resultados apontaram que os programas de p??s-gradua????o foram mais eficientes em 2006, seguido por 2004 e 2005, respectivamente. Notou- se ainda que, em m??dia, os programas vinculados ??s institui????es privadas de ensino foram mais eficientes que os da rede p??blica no tri??nio 2004/2006. Os gestores desses programas podem utilizar a an??lise da efici??ncia relativa como estrat??gia de benchmarking, adotando as melhores pr??ticas observadas nos programas eficientes, visando ?? maximiza????o da efici??ncia em sua gest??o.
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Introdução: Há cerca de duas décadas, a tuberculose (TB) foi considerada pela Organização Mundial de Saúde (OMS) como uma doença em estado de emergência em todo o mundo. Atualmente, apesar de todas as ações de controle da doença, ainda trata-se de um importante problema de saúde pública, apresentando forte relação com questões socioeconômicas, o que acarreta no maior adoecimento em grupos específicos, tais como a população privada de liberdade. Os dados de tuberculose em populações vulneráveis podem atingir índices ainda mais altos e por isso preocupante. Objetivos: Analisar as características clínicas e epidemiológicas associadas com os desfechos do tratamento da tuberculose na população privada de liberdade do Brasil, registrado no Sistema de Informação de Agravos de Notificação (SINAN), de 2007 a 2011; conhecer a taxa de incidência e de mortalidade por tuberculose na população privada de liberdade do Espírito Santo, de julho de 2009 a julho de 2010; e identificar as características clínicas e epidemiológicas dos casos diagnosticados de tuberculose na população privada de liberdade do Espírito Santo, de julho de 2009 a julho de 2010. Métodos: A população do estudo consistiu em presos diagnosticados com tuberculose identificados através do SINAN, entre janeiro de 2007 e dezembro de 2011 e dos casos diagnosticados de tuberculose na população prisional do Espírito Santo no período de 1º de julho de 2009 a 30 de junho de 2010. O teste de qui-quadrado de Pearson e o modelo de regressão polinomial foram utilizados na analise, além de estatística descritiva, por meio de tabelas e gráficos. Resultados: Em relação pacientes com TB na população privada de liberdade do Brasil, nota-se que os presos que abandonaram o tratamento eram mais jovens (P <0,001), com menor escolaridade (P <0,001) e maior probabilidade de alcoolismo (P < 0,001), eram mais propensos a ter TB recorrente ou recidiva (P < 0,001) e eles não estavam sob tratamento diretamente observado (TDO) (P < 0,001), comparados com aqueles que completaram o tratamento da tuberculose. Aqueles que morreram de tuberculose tendem a ter idade ⩾ 43 anos (P < 0,001) e alcoolistas (P < 0,001), também eram mais propensos a tipo de tratamento desconhecido (P <0,001) e apresentar tuberculose pulmonar e tuberculose extrapulmonar (TBEP). Presos que desenvolveram tuberculose multidroga resistente (TB-MDR) foram mais propensos a 9 experiência de recorrência de TB, retorno após abandono e transferência de local de tratamento. Além disso, observou-se 167 casos de tuberculose (taxa de incidência de 1962,6 por 100 mil presos) no Espírito Santo. O sexo masculino apresentou maior número de pacientes, assim como a faixa etária de 25 a 36 anos e a forma clínica pulmonar. Destaca-se que 109 (65,3%) pacientes tiveram alta por cura, ocorrendo dois óbitos durante o período, sendo a taxa de mortalidade por tuberculose de 11,7 por 100 mil presos. A maior incidência da tuberculose foi em pacientes localizados nas unidades prisionais da Região Metropolitana e um pequeno número de casos ocorreu em outros locais externos às unidades prisionais. Conclusão: Nossos resultados destacam a necessidade de melhorar as políticas de controle da TB nas penitenciárias, bem como os desfechos do tratamento de presos a fim de impedir a transmissão para outros presos, seus familiares e profissionais de saúde.
Resumo:
A presente dissertação investiga o atual estágio de manutenção das variedades dialetais da Itália setentrional no município de Santa Teresa, localizado na região serrana do Espírito Santo. Este trabalho se justifica porque, após 141 anos da chegada dos primeiros italianos a esse município, ainda não existem estudos que abordem questões relacionadas aos dialetos italianos da localidade. Considerando esse cenário, o objetivo deste estudo é oferecer um panorama da situação bilíngue português-dialeto italiano no município, com a identificação das áreas de maior ou menor uso do dialeto e ainda os fatores determinantes para a escolha linguística, os domínios de uso e as atitudes linguísticas dos falantes. Um segundo objetivo do estudo foi documentar algumas tradições orais italianas ainda presentes em Santa Teresa. Os dados foram coletados por meio de observação participante, questionário sociolinguístico e 146 entrevistas semiestruturadas, nas quais os informantes foram divididos por local de residência (zona rural e urbana) e em três faixas etárias (entre 08-30 anos, 31-60 e acima de 60 anos de idade). Os resultados encontrados revelam que o termo taliàn, que significa italiano nos dialetos da Itália setentrional (cf. BOERIO, 1856; RICCI, 1906 etc.), é usado pela maior parte dos falantes da faixa etária acima de 60 anos das zonas rural e urbana. Analisando diacronicamente o processo de uso do dialeto italiano através dos diferentes domínios, no período da infância dos informantes e na atualidade, é possível verificar a perda do dialeto no trajeto de vida dos falantes das faixas etárias de 31-60 anos e dos acima de 60 anos. Entre os informantes da faixa etária de 08-30 anos, verifica-se um quase completo monolinguismo português. Entre os informantes da faixa etária de 31-60 anos, o uso do dialeto italiano é fortemente influenciado pela idade do interlocutor: usam-no mais com seus avós do que com seus pais, e com seus pais mais do que com seus irmãos. Entretanto, nenhum informante desta faixa etária relatou usar o dialeto italiano com os filhos. Em resumo, o uso do dialeto italiano somente entre os membros mais idosos indica o processo de sua substituição pelo português e aponta que sua transmissão às gerações mais jovens está seriamente ameaçada. A análise das atitudes linguísticas dos informantes acima de 60 anos permitiu constatar o desprestígio e o preconceito em relação ao uso do dialeto no período da infância dos informantes. Por outro lado, os relatos em relação ao uso do dialeto na atualidade referem-se à associação da língua e da cultura de origem italiana com elementos positivos; à vontade explícita de manutenção do dialeto pelos adultos e idosos, à recuperação da língua de imigração pelos informantes de 08-30 anos. Aliás, entre os mais jovens, percebe-se uma tentativa de retorno às origens, de valorização da cultura e da língua dos antepassados.
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Companies’ decision to pay dividends to its shareholders is a topic that has received increasing attention in business finance. This paper provides an additional contribution to the development of this topic focusing on the analysis of the determinants of dividend policy by issuing companies in the Portuguese capital market. For this purpose, we use a set of financial and economic information specific to each firm to explain its dividend per share. The sample used in the empirical study contains 54 firms and it refers to the 2005-2009 period. Results suggest that net income, dividends per share paid in the previous financial year and return on assets all present a positive and statistically significant effect on dividends per share paid in a given financial year. Moreover, results show that Lintner’s (1956) model appears to be valid in explaining dividend policy by issuing companies in Euronext Lisbon.
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Work-related musculoskeletal disorders (WMSDs) are among the most costly health problems that society is facing today. Prevention involves investments and it is important for organizations to make a cost ebenefit analysis of ergonomic projects. Return on prevention is a recent concern in the domain of occupational safety and health (OSH). There are many studies concerning the return on the prevention of WMSDs, in terms of the benefits for the organization in which the preventive measures are implemented. However, it is also important to perform an analysis of the impact of each measure on society (externalities). A model to perform a financial and economic costebenefit analysis related to OSH projects was developed and it was applied in the case of the prevention of WMSDs in a Portuguese hospital. An analysis of the accidents and corresponding costs has been made in six of the services of the hospital. Financial and an economic costebenefit analysis have been made and the benefitecost ratio (B/C) has been calculated. While the B/C financial ratio, considering only the benefits to the hospital, is around 2, the economic B/C ratio, taking into account all the external benefits that have been quantified, is higher than 14. Relevance to industry: Both the economic and the financial B/C ratio are important support tools for decision makers in public and private organizations, helping them to define which preventive measures should be implemented, taking into account the costs involved and the resulting quantified benefits, for the organization, for the workers and for the society.
Resumo:
The purpose of this research is fourfold. First, to investigate whether the determinants of international equity investment differ between investors with different degrees of information, experience and sophistication. For this purpose, the determinants of international equity investment of institutional and noninstitutional investors from 20 OECD countries, in the period 2001-2009, were analysed and compared. The results show that there are significant differences in the determinants of international equity investment between institutional and noninstitutional investors. Particularly, noninstitutional investors exhibit a more pronounced preference for equities of geographical nearby, contiguous and more transparent countries than institutional investors, suggesting that the effect of information costs and familiarity on international equity investment is stronger for less informed, experienced and sophisticated investors. Moreover, the preference for more developed equity markets and the contrarian behaviour are more severe for noninstitutional investors. Hence, the heterogeneity of institutional and noninstitutional investors in international equity investment is not negligible and therefore should be taken into account. Second, to investigate whether the determinants of international bond investment differ between investors with different degrees of information, experience and sophistication. For this purpose, the determinants of international bond investment of institutional and noninstitutional investors from 20 OECD countries, in the period 2001-2009, were analysed and compared. The results show that there are few significant differences in the determinants of international bond investment between institutional and noninstitutional investors. Particularly, the preference for bonds of more transparent countries and the return chasing behaviour are more pronounced for noninstitutional investors, whereas the preference for bonds with lower risk diversification potential is more pronounced for institutional investors. Hence, not only the results for international bond investment do not allow to support (or reject) the argument that information costs and familiarity are more important for less informed, experienced and sophisticated investors, but also they are contrary to the idea that financial variables, namely return and risk diversification, are more important for more informed, experienced and sophisticated investors. Third, to investigate whether the determinants of international equity investment differ from the determinants of international bond investment. For this purpose, the determinants of both international equity and bond investment of institutional and noninstitutional investors from 20 OECD countries, in the period 2001-2009, were analysed and compared. The results show that, although the effect of information costs on international equity investment tends to be stronger than on international bond investment, the differences between assets are not usually statistically significant, especially when the influence of financial variables is taken into account. Hence, it is not possible to conclude that international equity investment is much more information intensive than international bond investment, as suggested by Gehrig (1993) and Portes, Rey and Oh (2001), among others. Fourth, to investigate whether the flight to quality phenomenon is also observable in international investment and whether the flight to quality phenomenon is more pronounced for more sophisticated than for less sophisticated investors. For this purpose, a two-factor and three-factor ANOVA models, respectively, were applied to the international equity and bond investment of institutional and noninstitutional investors from 20 OECD countries in the period 2001-2009. The results suggest that the flight to quality phenomenon is also observable in international investment, as a change from business cycle of expansion to recession causes investors to significantly decrease the average weight invested in more risky assets (equities) and increase the average weight invested in less risky assets (bonds). The results also show that the variation on the average weight assigned to each type of asset, due to changes in business cycles, is significantly stronger for institutional investors than for noninstitutional investors, thereby suggesting that the flight to quality phenomenon is more pronounced for more sophisticated than for less sophisticated investors.
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This study examines the relationship between the environmental performance and the financial performance of Portuguese corporations, based on a sample of 35 stocks listed in the Euronext Lisbon stock exchange, for the period from 2000 to 2004. Corporate environmental performance is measured by an analysis of the environmental information disclosed in 2003 corporate annual financial reports. Stock market-based measures, such as return, risk and risk-adjusted return measures, are used to evaluate corporate financial performance, for the 5 years observation period. We use the portfolio studies and contingency tables methodology to evaluate the relationship between corporate environmental disclosures and corporate stock market performance. The empirical results suggest that companies that do not disclose environmental information have a superior financial performance – as measured by return, risk and risk-adjusted return – than those that disclose environmental information. In particular, companies with better environmental reporting, which disclose qualitative and quantitative environmental information, are the ones with worse financial performance. Nevertheless the differences found in financial performance are not statistically significant. The empirical results are thus adverse to the more recent view of environmental performance as a competitive advantage, maybe due to the still relatively small importance of environmental issues to companies and investors.