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111.
M Moritz S Laborde SC Phang M Ahmadou M Durand A Fernandez 《African Journal of Aquatic Science》2016,41(1):99-108
African floodplains are an excellent example of coupled human–natural systems because they exhibit strong interactions among multiple social, ecological, and hydrological systems. The intra-annual and interannual variations in seasonal flooding have direct and indirect impacts on ecosystems and human lives and livelihoods. Coupled human and natural system (CHANS) is a broad conceptual framework that is used to study systems in which human and natural components interact. While there are other conceptual frameworks to study social-ecological systems, the CHANS framework offers a clear way of studying the interactions, called couplings, between human and natural systems. Core features of the framework are the following: human and natural systems are analytically separated; focus is on processes within and couplings between systems; and the goal is to build an integrative, quantitative model of the coupled system. This paper explains the conceptual framework of coupled systems, using the case study of the Logone floodplain in Cameroon. We compare the CHANS framework with other frameworks that have been used to study the same floodplain, and argue for its usefulness in the study of African floodplains. 相似文献
112.
The effects of selective ibotenate lesions of the complete hippocampus (CHip), the hippocampal ventral pole (VP), or the medial prefrontal cortex (mPFC) in male rats were assessed on several measures related to energy regulation (i.e., body weight gain, food intake, body adiposity, metabolic activity, general behavioral activity, conditioned appetitive responding). The testing conditions were designed to minimize the nonspecific debilitating effects of these surgeries on intake and body weight. Rats with CHip and VP lesions exhibited significantly greater weight gain and food intake compared with controls. Furthermore, CHip-lesioned rats, but not rats with VP lesions, showed elevated metabolic activity, general activity in the dark phase of the light-dark cycle, and greater conditioned appetitive behavior, compared with control rats without these brain lesions. In contrast, rats with mPFC lesions were not different from controls on any of these measures. These results indicate that hippocampal damage interferes with energy and body weight regulation, perhaps by disrupting higher-order learning and memory processes that contribute to the control of appetitive and consummatory behavior. 相似文献
113.
甘草黄酮类化合物对酪氨酸酶单酚酶的抑制 总被引:6,自引:4,他引:2
研究了甘草中四种黄酮类化合物甘草甙、异甘草素.葡萄糖芹菜甙、异甘草甙和甘草查耳酮甲对酪氨酸酶单酚酶活性的抑制。结果表明异甘草素-葡萄糖芹菜甙、异甘草甙和甘草查耳酮甲的IC50分别为0.072mM,,0.038mM,0.0258mM,它们都属于竞争性抑制剂,甘草甙没有抑制活性。研究表明,异甘草素.葡萄糖芹菜甙、异甘草甙和甘草查耳酮甲可以作为潜在的美白化妆品添加剂。 相似文献
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