In the early part of the twentieth century, neoclassical economic theorists began to explore mathematical models of maximization. The theories of human behavior that they produced explored how optimal human agents, who were subject to no internal computational resource constraints of any kind, should make choices. During the second half of the twentieth century, empirical work laid bare the lim...

Development and projections in the field of PDAs and wireless communication architectures let us consider new applications which exploit short range and direct exchanges. In a close future we may imagine mobile users equipped with wireless PDAs dynamically and spontaneously exchanging rich information in an ad hoc manner. In such a context, a connection between two PDAs may be broken at any tim...

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There is disagreement in the literature about the exact nature of the phenomenon of empathy. There are emotional, cognitive, and conditioning views, applying in varying degrees across species. An adequate description of the ultimate and proximate mechanism can integrate these views. Proximately, the perception of an object's state activates the subject's corresponding representations, which in ...

Received 8/8/2012 Accepted 7/3/2013 (005796) 1 Departamento de Nutrição Básica e Experimental, Centro de Ciências da Saúde, Instituto de Nutrição Josué de Castro, Universidade Federal do Rio de Janeiro – UFRJ, Av. Brigadeiro Trompowisky, s/n, bloco J, 2o andar, sala 16, CEP 21941-902, Rio de Janeiro, RJ, Brazil, e-mail: [email protected] 2 Centro de Química de Alimentos e Nutrição Ap...

Rainbow trout, Oncorhynchus mykiss can be classified as the premier salmonid species. It is one of the most famous fish species in nature. At the same time, is also recognized and accepted as farmed fish species in many countries, because of its exceptional nutritive quality, rapid growth (Tekeliog, 2000) and exceptionally tolerant to environmental conditions (Simonovic, 2001). Worldwide produc...

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The dramatic decline in mortality rates during the nineteenth century put the countries of the world into an imbalanced stage of demographic transition. Developed societies adopted fertility control methods and achieved a balance in their annual rate of population growth, whilst developing countries and traditional societies are still confronted with the following serious hazards: 1. Poor healt...

In more than 95% of mammalian species, males provide little direct investment in the well-being of their offspring. Humans are one notable exception to this pattern and, to date, the factors that contributed to the evolution and the proximate expression of human paternal care are unexplained (T. H. Clutton-Brock, 1989). The nature, extent, and influence of human paternal investment on the physi...