1000 resultados para Eficiência global
Resumo:
We use aggregate GDP data and within-country income shares for theperiod 1970-1998 to assign a level of income to each person in theworld. We then estimate the gaussian kernel density function for theworldwide distribution of income. We compute world poverty rates byintegrating the density function below the poverty lines. The $1/daypoverty rate has fallen from 20% to 5% over the last twenty five years.The $2/day rate has fallen from 44% to 18%. There are between 300 and500 million less poor people in 1998 than there were in the 70s.We estimate global income inequality using seven different popularindexes: the Gini coefficient, the variance of log-income, two ofAtkinson s indexes, the Mean Logarithmic Deviation, the Theil indexand the coefficient of variation. All indexes show a reduction in globalincome inequality between 1980 and 1998. We also find that most globaldisparities can be accounted for by across-country, not within-country,inequalities. Within-country disparities have increased slightly duringthe sample period, but not nearly enough to offset the substantialreduction in across-country disparities. The across-country reductionsin inequality are driven mainly, but not fully, by the large growth rateof the incomes of the 1.2 billion Chinese citizens. Unless Africa startsgrowing in the near future, we project that income inequalities willstart rising again. If Africa does not start growing, then China, India,the OECD and the rest of middle-income and rich countries diverge awayfrom it, and global inequality will rise. Thus, the aggregate GDP growthof the African continent should be the priority of anyone concerned withincreasing global income inequality.
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Astrocytes are responsible for regulating extracellular levels of glutamate and potassium during neuronal activity. Glutamate clearance is handled by glutamate transporter subtypes glutamate transporter 1 and glutamate-aspartate transporter in astrocytes. DL-threo-beta-benzyloxyaspartate (TBOA) and dihydrokainate (DHK) are extensively used as inhibitors of glial glutamate transport activity. Using whole-cell recordings, we characterized the effects of both transporter inhibitors on afferent-evoked astrocyte currents in acute cortical slices of 3-week-old rats. When neuronal afferents were stimulated, passive astrocytes responded by a rapid inward current followed by a persistent tail current. The first current corresponded to a glutamate transporter current. This current was inhibited by both inhibitors and by tetrodotoxin. The tail current is an inward potassium current as it was blocked by barium. Besides inhibiting transporter currents, TBOA strongly enhanced the tail current. This effect was barium-sensitive and might be due to a rise in extracellular potassium level and increased glial potassium uptake. Unlike TBOA, DHK did not enhance the tail current but rather inhibited it. This result suggests that, in addition to inhibiting glutamate transport, DHK prevents astrocyte potassium uptake, possibly by blockade of inward-rectifier channels. This study revealed that, in brain slices, glutamate transporter inhibitors exert complex effects that cannot be attributed solely to glutamate transport inhibition.
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In this paper, we use a unique long-run dataset of regulatory constraints on capital account openness to explain stock market correlations. Since stock returns themselves are highly volatile, any examination of what drives correlations needs to focus on long runs of data. This is particularly true since some of the short-term changes in co-movements appear to reverse themselves (Delroy Hunter 2005). We argue that changes in the co-movement of indices have not been random. Rather, they are mainly driven by greater freedom to move funds from one country to another. In related work, Geert Bekaert and Campbell Harvey (2000) show that equity correlations increase after liberalization of capital markets, using a number of case studies from emerging countries. We examine this pattern systematically for the last century, and find it to be most pronounced in the recent past. We compare the importance of capital account openness with one main alternative explanation, the growing synchronization of economic fundamentals. We conclude that greater openness has been the single most important cause of growing correlations during the last quarter of a century, though increasingly correlated economic fundamentals also matter. In the conclusion, we offer some thoughts on why the effects of greater openness appear to be so much stronger today than they were during the last era of globalization before 1914.
Resumo:
Desde os primórdios da civilização as relações internacionais fazem parte das preocupações do homem. Quase simultaneamente às interrogações sobre a natureza e o alcance do poder dentro das comunidades, fossem impérios, reinos ou cidades-Estado, surgiram também as primeiras tentativas de demonstrar a natureza das relações internacionais. A mais famosa dessas teorias na Antiguidade foi a desenvolvida pelo grego Tucídides, na História da Guerra do Peloponeso.
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O ácaro Brevipalpus phoenicis é encontrado nos cafezais do Brasil desde a década de 50. Responsável por perdas indiretas por ser o vetor de uma doença virótica requer constantes medidas de controle, sendo a mais utilizada baseada na pulverização de acaricidas. Avaliou-se a mortalidade do ácaro B. phoenicis em função da cobertura de calda aplicada em plantas de café, com dois tipos de ramais utilizados em pulverizadores de jato transportado e quatro volumes de aplicação. O produto utilizado para o trabalho foi o acaricida abamectina (Vertimec 18 CE® na dose de 0,4 L/ha). Os tratamentos utilizados foram a aplicação do acaricida abamectina, nos volumes de 250, 400, 550 e 700 L/ha, com dois tipos de ramais de bicos. Em cada tratamento foram avaliadas a eficiência de controle de B. phoenicis, a deposição e a cobertura da calda nas plantas de café. O delineamento experimental utilizado foi em blocos casualizados, com oito tratamentos mais uma testemunha e quatro repetições. A análise estatística foi realizada no esquema fatorial 2x4+1. Verificou-se que não houve diferenças significativas no número de ácaros encontrados entre os tratamentos. Para a deposição de calda, observou-se um aumento em função do volume de aplicação, sendo que a parte superior das plantas apresentou maior deposição de produto. A duplicação dos ramais resultou em um aumento significativo da eficiência de controle de B. phoenicis comparado ao ramal convencional e à testemunha, independe do volume de aplicação entre os limites avaliados.
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PURPOSE: The objective was to explore whether a satellite-based navigation system, global positioning system used in differential mode (DGPS), could accurately assess the speed of running in humans. METHODS: A subject was equipped with a portable GPS receptor coupled to a receiver for differential corrections, while running outdoors on a straight asphalt road at 27 different speeds. Actual speed (reference method) was assessed by chronometry. RESULTS: The accuracy of speed prediction had a standard deviation (SD) of 0.08 km x h(-1) for walking, 0.11 km x h(-1) for running, yielding a coefficient of variation (SD/mean) of 1.38% and 0.82%, respectively. There was a highly significant linear relationship between actual and DGPS speed assessment (r2 = 0.999) with little bias in the prediction equation, because the slope of the regression line was close to unity (0.997). CONCLUSION: the DGPS technique appears to be a valid and inconspicuous tool for "on line" monitoring of the speed of displacement of individuals located on any field on earth, for prolonged periods of time and unlimited distance, but only in specific environmental conditions ("open sky"). Furthermore, the accuracy of speed assessment using the differential GPS mode was improved by a factor of 10 as compared to non-differential GPS.
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The rapid stopping of specific parts of movements is frequently required in daily life. Yet, whether selective inhibitory control of movements is mediated by a specific neural pathway or by the combination between a global stopping of all ongoing motor activity followed by the re-initiation of task-relevant movements remains unclear. To address this question, we applied time-wise statistical analyses of the topography, global field power and electrical sources of the event-related potentials to the global vs selective inhibition stimuli presented during a Go/NoGo task. Participants (n = 18) had to respond as fast as possible with their two hands to Go stimuli and to withhold the response from the two hands (global inhibition condition, GNG) or from only one hand (selective inhibition condition, SNG) when specific NoGo stimuli were presented. Behaviorally, we replicated previous evidence for slower response times in the SNG than in the Go condition. Electrophysiologically, there were two distinct phases of event-related potentials modulations between the GNG and the SNG conditions. At 110âeuro"150 ms post-stimulus onset, there was a difference in the strength of the electric field without concomitant topographic modulation, indicating the differential engagement of statistically indistinguishable configurations of neural generators for selective and global inhibitory control. At 150âeuro"200 ms, there was topographic modulation, indicating the engagement of distinct brain networks. Source estimations localized these effects within bilateral temporo-parieto-occipital and within parieto-central networks, respectively. Our results suggest that while both types of motor inhibitory control depend on global stopping mechanisms, selective and global inhibition still differ quantitatively at early attention-related processing phases.
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A economia digital suportada na Internet é hoje um poderoso instrumento para a realização de negócios e o turismo considerado a indústria do futuro pode adaptar este espaço como domínio de realização de venda/troca/ compra de produtos turísticos. O trabalho que ora se apresenta, tem como tema (Mercado Electrónico dos Serviços Turísticos e Viagens estudo de caso da presença de Cabo Verde e São Tomé e Príncipe como destino nos grandes operadores do mercado global). O trabalho está constituído por três capítulos, conclusão e recomendações. No primeiro capítulo, apresentamos as tendências actuais no comércio electrónico. No segundo capítulo, verificamos formas de funcionamento de grandes Agências de Viagens on-line, como a http://www.edreams.es, www.promovacances.com e http://www.exit.pt. A análise foi feita com base em alguns itens da tabela de James L. Horton, como: caracterização da agência, o público-alvo, o objectivo da página web, o conteúdo, o desenho e apresentação, a interactividade e o feedback. No terceiro e último capítulo, que constitui o estudo de caso do nosso trabalho verificamos as ofertas dos produtos e serviços turísticos de Cabo Verde e São Tomé e Príncipe, nas agências de viagens on-line de prestigio, www.edreams.es, www.promovacances.com e www.exit.pt, grandes operadores turísticos disponíveis na Internet. Primeiramente apresentamos as potencialidades turísticas de Cabo Verde e São Tomé e Príncipe, e confronta-las com a forma como aparecem nestas agências de viagens. Verificaremos, a forma de apresentação, os preços, os produtos e serviços oferecidos, a atractividade das ofertas, produtos especializados. A realização deste trabalho foi feito com base na pesquisa documental, análise do conteúdo como estatística paramétrica e conversas com profissionais da área do turismo. O trabalho foi desenvolvido nos meses de Março ao Julho de 2007.
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In this paper we argue that corporate social responsibility (CSR) to various stakeholders(customers, shareholders, employees, suppliers, and community) has a positive effect on globalbrand equity (BE). In addition, policies aimed at satisfying community interests help reinforcecredibility to social responsible polices with other stakeholders. We test these theoreticalcontentions using panel data comprised of 57 global brands originating from 10 countries (USA,Japan, South Korea, France, UK, Italy, Germany, Finland, Switzerland and the Netherlands) forthe period 2002 to 2008. Our findings show that CSR to each of the stakeholder groups has apositive impact on global BE. In addition, global brands that follow local social responsibilitypolicies over communities obtain strong positive benefits in terms of the generation of BE, as itenhances the positive effects of CSR to other stakeholders, particularly to customers. Therefore,for managers of global brands it is particularly productive for generating brand value to combineglobal strategies with the satisfaction of the interests of local communities.
Potencialidades do Campus Virtual Global Aplicações práticas da utilização da plataforma de educação
Resumo:
A utilização do Campus Virtual Global do Instituto Piaget como instrumento obrigatório no processo de aprendizagem. As ferramentas do Campus aproximam docentes e discentes, aumentam a cooperação, proporcionam maior participação dos alunos e propiciam o consequente desenvolvimento de competências. A nova ênfase do trabalho docente deixa para segundo plano o discurso de retórica e a exposição tradicional e centra-se nos alunos; o professor propõe tarefas e actividades contínuas, apoiadas em ferramentas que propiciam o diálogo socrático.
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Nessa nossa primeira abordagem à problemática ecológica propomos uma reflexão sobre as formas de relacionamento homem/natureza procurando a génese e relevância do pensamento ecológico bem como o seu papel fundamentador de uma proposta de educação para uma cidadania global – natural e social. Emergem da nossa análise as concepções de natureza-mãe-toda-poderosa, natureza passiva, natureza dinâmica e complexa, concepções estas que traduzem formas peculiares de relação homem-natureza (relações subordinação, de domínio, exploração, de diálogo, e equilíbrio) as quais suportam modelos de acção e intervenção humana na natureza e configuram os próprios modelos de desenvolvimento adoptados. A liberdade e a responsabilidade definidas pelo humanismo como as bases do agir humano são prolongadas pela ética ecológica a bem de uma sociedade mais harmónica e humanizada.
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The demand for accurate forecasting of the effects of global warming on biodiversity is growing, but current methods for forecasting have limitations. in this article, we compare and discuss the different uses of four forecasting methods: (1) models that consider species individually, (2) niche-theory models that group species by habitat (more specifically, by environmental conditions under which a species can persist or does persist), (3) general circulation models and coupled ocean-atmosphere-biosphere models, and (4) specics-area curve models that consider all species or large aggregates of species. After outlining the different uses and limitations of these methods, we make eight primary suggestions for improving forecasts. We find that greater use of the fossil record and of modern genetic studies would improve forecasting methods. We note a Quaternary conundrum: While current empirical and theoretical ecological results suggest that many species could be at risk from global warming, during the recent ice ages surprisingly few species became extinct. The potential resolution of this conundrum gives insights into the requirements for more accurate and reliable forecasting. Our eight suggestions also point to constructive synergies in the solution to the different problems.