850 resultados para Open clusters and associations: individual: SL 639
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This commentary situates the second person account within a broader framework of ecological validity for experimental paradigms in social cognitive neuroscience. It then considers how individual differences at psychological and genetic levels can be integrated within the proposed framework.
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This paper discusses 226 earlier Neolithic pits found at Kilverstone in Norfolk. In particular, it focuses on the dynamics involved in the site's creation, investigating what had happened to the material found in the pits prior to deposition, and exploring the material connections (refitting sherds and flints) across the site. As a result of these material insights, it proved possible to shed important light on the character of that place in particular, and on the temporality of Neolithic deposition and occupation in general.
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Individual-based models (IBMs) can simulate the actions of individual animals as they interact with one another and the landscape in which they live. When used in spatially-explicit landscapes IBMs can show how populations change over time in response to management actions. For instance, IBMs are being used to design strategies of conservation and of the exploitation of fisheries, and for assessing the effects on populations of major construction projects and of novel agricultural chemicals. In such real world contexts, it becomes especially important to build IBMs in a principled fashion, and to approach calibration and evaluation systematically. We argue that insights from physiological and behavioural ecology offer a recipe for building realistic models, and that Approximate Bayesian Computation (ABC) is a promising technique for the calibration and evaluation of IBMs. IBMs are constructed primarily from knowledge about individuals. In ecological applications the relevant knowledge is found in physiological and behavioural ecology, and we approach these from an evolutionary perspective by taking into account how physiological and behavioural processes contribute to life histories, and how those life histories evolve. Evolutionary life history theory shows that, other things being equal, organisms should grow to sexual maturity as fast as possible, and then reproduce as fast as possible, while minimising per capita death rate. Physiological and behavioural ecology are largely built on these principles together with the laws of conservation of matter and energy. To complete construction of an IBM information is also needed on the effects of competitors, conspecifics and food scarcity; the maximum rates of ingestion, growth and reproduction, and life-history parameters. Using this knowledge about physiological and behavioural processes provides a principled way to build IBMs, but model parameters vary between species and are often difficult to measure. A common solution is to manually compare model outputs with observations from real landscapes and so to obtain parameters which produce acceptable fits of model to data. However, this procedure can be convoluted and lead to over-calibrated and thus inflexible models. Many formal statistical techniques are unsuitable for use with IBMs, but we argue that ABC offers a potential way forward. It can be used to calibrate and compare complex stochastic models and to assess the uncertainty in their predictions. We describe methods used to implement ABC in an accessible way and illustrate them with examples and discussion of recent studies. Although much progress has been made, theoretical issues remain, and some of these are outlined and discussed.
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Using the first-principles real-space linear muffin-tin orbital method within the atomic sphere approximation (RS-LMTO-ASA) we study hyperfine and local magnetic properties of substituted pure Fe and Fe-Cu clusters in an fcc Cu matrix. Spin and orbital contributions to magnetic moments, hyperfine fields and the Mossbauer isomer shifts at the Fe sites in Fe precipitates and Fe-Cu alloy clusters of sizes up to 60 Fe atoms embedded in the Cu matrix are calculated and the influence of the local environment on these properties is discussed.
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Este estudo analisa como a classe de acionistas afeta o valor das empresas brasileiras listadas na bolsa de valores no ponto de vista da governança corporativa. O trabalho examina a interação entre o valor das empresas e cinco tipos de concentrações acionárias comumente presente em mercados emergentes: famílias, agentes públicos, investidores estrangeiros, executivos e investidores financeiros nacionais. A análise empírica demonstra que o mix e a concentração de participação acionária afeta significativamente o valor das empresas. Utilizando uma compilação única de dados em painel de 2004 a 2008, a presente pesquisa também desenvolve hipóteses sobre o efeito da participação em grupos econômicos para o valor das empresas. A investigação encontra evidências de que, apesar de sua importância para o desenvolvimento de empresas brasileiras, o capital familiar, instituições públicas, e investidores estrangeiros estão cedendo lugar a monitores mais especializados e menos concentrados, como executivos e instituições financeiras nacionais. Estes resultados indicam que a governança corporativa no Brasil pode estar alcançando níveis de maturidade mais elevados. Adicionalmente, apesar de não haver indicação da existência de correlação entre a participação em grupos econômicos e o valor das empresas, os resultados indicam que a presença de um tipo específico de acionista em uma empresa do grupo facilita investimentos futuros desta classe de acionista em outras empresas do mesmo grupo, sinalizando que os interesses acionários são provavelmente perpetuados dentro de uma mesma rede de empresas. Finalmente, a pesquisa demonstra que enquanto o capital familiar prefere investir em empresas com ativa mobilidade do capital, investidores internacionais e instituições públicas procuram investimentos em equity com menor mobilidade de capital, o que lhes garante mais transparência com relação ao uso dos recursos e fundos das empresas.
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This paper considers challenges of Human Resource Management (HRM) in Open Innovation processes. It examines which strategies managers used to overcome these problems in the case of the Brazilian Oil and Gas company Petrobras. By conducting an inductive case study it develops a contextual model based on the use of grounded theory. It argues that the most important categories were to overcome problems of (a) the interpersonal relationship, (b) power shifting inside the organization, and (c) making people more valuable to the organization and shows how managers tackled these challenges. It contributes with a deep analysis of HRM challenges in Open Innovation that is important for a better understanding of management problems that can come along with Open Innovation processes.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The entropy of the states associated to the solutions of the equations of motion of the bosonic open string with combinations of Neumann and Dirichlet boundary conditions is given. Also, the entropy of the string in the states \A(i)] = alpha(-1)(i)\0] and \phi(a)]= alpha(-1)(a)\0] that describe the massless fields on the world-volume of the Dp-brane is computed. (C) 2002 Elsevier B.V. B.V. All rights reserved.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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In recent years, many researchers in the field of biomedical sciences have made successful use of mathematical models to study, in a quantitative way, a multitude of phenomena such as those found in disease dynamics, control of physiological systems, optimization of drug therapy, economics of the preventive medicine and many other applications. The availability of good dynamic models have been providing means for simulation and design of novel control strategies in the context of biological events. This work concerns a particular model related to HIV infection dynamics which is used to allow a comparative evaluation of schemes for treatment of AIDS patients. The mathematical model adopted in this work was proposed by Nowak & Bangham, 1996 and describes the dynamics of viral concentration in terms of interaction with CD4 cells and the cytotoxic T lymphocytes, which are responsible for the defense of the organism. Two conceptually distinct techniques for drug therapy are analyzed: Open Loop Treatment, where a priori fixed dosage is prescribed and Closed Loop Treatment, where the doses are adjusted according to results obtained by laboratory analysis. Simulation results show that the Closed Loop Scheme can achieve improved quality of the treatment in terms of reduction in the viral load and quantity of administered drugs, but with the inconvenience related to the necessity of frequent and periodic laboratory analysis.