3 resultados para Tri-State Modulation and Control

em Bucknell University Digital Commons - Pensilvania - USA


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Semiempirical molecular orbital calculations have been performed for the first step in the alkaline hydrolysis of the neutral benzoylester of cocaine. Successes, failures, and limitations of these calculations are reviewed. A PM3 calculated transition state structure is compared with the PM3 calculated structure for the hapten used to induce catalytic antibodies for the hydrolysis of cocaine. Implications of these calculations for the computer–aided design of transition state analogs for the induction of catalytic antibodies are discussed.

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Evolutionary transitions between aquatic and terrestrial environments are common in vertebrate evolution. These transitions require major changes in most physiological functions, including feeding. Emydid turtles are ancestrally aquatic, with most species naturally feeding only in water, but some terrestrial species can modulate their feeding behavior appropriately for both media. In addition, many aquatic species can be induced to feed terrestrially. A comparison of feeding in both aquatic and terrestrial environments presents an excellent opportunity to investigate the evolution of terrestrial feeding from aquatic feeding, as well as a system within which to develop methods for studying major evolutionary transitions between environments. Individuals from eight species of emydid turtles (six aquatic, two terrestrial) were filmed while feeding underwater and on land. Bite kinematics were analyzed to determine whether aquatic turtles modulated their feeding behavior in a consistent and appropriate manner between environments. Aquatic turtles showed consistent changes between environments, taking longer bites and using more extensive motions of the jaw and hyoid when feeding on land. However, these motions differ from those shown by species that naturally feed in both environments and mostly do not seem to be appropriate for terrestrial feeding. For example, more extensive motions of the hyoid are only effective during underwater suction feeding. Emydids evolving to feed on land probably would have needed to evolve or learn to overcome many, but not all, aspects of the intrinsic emydid response to terrestrial feeding. Studies that investigate major evolutionary transitions must determine what responses to the new environment are shown by naïve individuals in order to fully understand the evolutionary patterns and processes associated with these transitions.

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This article offers an analysis of a struggle for control of a women’s development project in Nepal. The story of this struggle is worth telling, for it is rife with the gender politics and neo-colonial context that underscore much of what goes on in contemporary Nepal. In particular, my analysis helps to unravel some of the powerful discourses, threads of interest, and yet unintended effects inevitable under a regime of development aid. The analysis demonstrates that the employment of already available discursive figures of the imperialist feminist and the patriarchal third world man are central to the rhetorical strategies taken in the conflict. I argue that the trans-discursive or “borderland” nature of development in general and women’s development in particular result in different constructions of “development” goals, means and actors based not only on divergent cultural categories but on historically specific cultural politics. I argue further that the apolitical discourse of development serves to cloak its inherently political project of social and economic transformation, making conflicts such as the one that occurred in this case not only likely to occur but also likely to be misunderstood.