82 research outputs found

    Toxicity of copaiba extracts to armyworm (Spodoptera frugiperda)

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    The objective of this study was to evaluate the effects of methanolic extracts from leaves, peels, seeds and pulps from fruits of Copaifera langsdorffii on Spodoptera frugiperda. Extracts derived from leaves and fruit peels were more toxic to S. frugiperda than the others. Hence, they were added to the artificial diet and used in further experiments with the second instar larvae of the insect, which presented larval growth reduction, prolonged period of development, increased mortality, and lower fertility and fecundity of adults. Lower egg viability was also observed when the insect was treated with extracts of leaves and fruit peels in the larvae stage. Moreover, when subjected to ultrastructural analysis under a scanning electron microscope, such eggs showed abnormalities in the aeropylar and micropylar regions. Both extracts also increased the excretion of protein in the insect feces and inhibited trypsin activity in the in vitro test. Consequently, C. langsdorffii presents potential to be used in the development of new products to control the fall armyworm.Key words: Copaifera langsdorffii, natural products, trypsin inhibitor, botanical insecticide

    Differential information in large games with strategic complementarities

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    We study equilibrium in large games of strategic complementarities (GSC) with differential information. We define an appropriate notion of distributional Bayesian Nash equilibrium and prove its existence. Furthermore, we characterize order-theoretic properties of the equilibrium set, provide monotone comparative statics for ordered perturbations of the space of games, and provide explicit algorithms for computing extremal equilibria. We complement the paper with new results on the existence of Bayesian Nash equilibrium in the sense of Balder and Rustichini (J Econ Theory 62(2):385–393, 1994) or Kim and Yannelis (J Econ Theory 77(2):330–353, 1997) for large GSC and provide an analogous characterization of the equilibrium set as in the case of distributional Bayesian Nash equilibrium. Finally, we apply our results to riot games, beauty contests, and common value auctions. In all cases, standard existence and comparative statics tools in the theory of supermodular games for finite numbers of agents do not apply in general, and new constructions are required

    "Bomba hormonal": os riscos da contracepção de emergência na perspectiva dos balconistas de farmácias no Rio de Janeiro, Brasil

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    Resumo: A pesquisa objetivou conhecer a perspectiva dos balconistas de farmácias sobre a contracepção de emergência na Região Metropolitana do Rio de Janeiro, Brasil. O material empírico advém de pesquisa socioantropológica com vinte entrevistas semiestruturadas com balconistas dos sexos feminino (8) e masculino (12). Os entrevistados apresentam concepções negativas sobre a contracepção de emergência, enfatizando os riscos que ela pode provocar à saúde. O medicamento é considerado uma "bomba hormonal" que pode causar danos aos órgãos reprodutivos femininos e outros sistemas do corpo. Eles destacam os riscos do uso "descontrolado" ou "indiscriminado", especialmente por adolescentes e mulheres jovens. Por ser considerado "perigoso" aos corpos femininos, eles atribuem a responsabilidade de orientação e aconselhamento sobre o uso do método aos médicos ginecologistas e não aos farmacêuticos. Discute-se a necessidade de ampliação do debate público sobre contracepção de emergência no Brasil, incluindo-se os farmacêuticos e balconistas de farmácia, além dos profissionais de saúde e educadores

    Atomic spectrometry update – a review of advances in environmental analysis

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    Arthropod venom Hyaluronidases: biochemical properties and potential applications in medicine and biotechnology

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