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1.
Kruk Menno R.; Halász József; Meelis Wout; Haller József 《Canadian Metallurgical Quarterly》2004,118(5):1062
Aggressive behavior induces an adrenocortical stress response, and sudden stressors often precipitate violent behavior. Experiments in rats revealed a fast, mutual, positive feedback between the adrenocortical stress response and a brain mechanism controlling aggression. Stimulation of the aggressive area in the hypothalamus rapidly activated the adrenocortical response, even in the absence of an opponent and fighting. Hypothalamic aggression, in turn, was rapidly facilitated by a corticosterone injection in rats in which the natural adrenocortical stress response was prevented by adrenalectomy. The rapidity of both effects points to a fast, mutual, positive feedback of the controlling mechanisms within the time frame of a single conflict. Such a mutual facilitation may contribute to the precipitation and escalation of violent behavior under stressful conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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0.89dtex细旦涤纶短纤维工艺优化探讨 总被引:2,自引:1,他引:1
介绍了纺制 0 89dtex× 3 8mm细旦涤纶短纤维的工艺技术特点 ,着重讨论了熔体温度、纺丝速度、冷却条件等工艺对原丝性能及产品质量的影响 相似文献
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阐述了建筑给排水工程师在实际工作中除必须满足国家有关强制性规范外 ,还应采取一系列针对性技术措施 ,以使住宅的环境性能得到良好的控制 ,以提高住宅的品质。 相似文献
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Kahler Christopher W.; Read Jennifer P.; Wood Mark D.; Palfai Tibor P. 《Canadian Metallurgical Quarterly》2003,17(3):226
Structural equation modeling was used to test the mediational role of social environmental selection on alcohol use in cross-sectional samples of 447 students from a rural state university and 421 students from an urban private university. Results showed that male gender, White ethnicity, and sensation seeking were uniquely associated with greater alcohol use. Mediational analyses indicated that socioenvironmental factors (i.e., Greek involvement, friends' approval of drinking/getting drunk) were positively associated with alcohol use and significantly accounted for parts of the effects of ethnicity and sensation seeking, but not gender, on alcohol use. Results suggest that White students and those high on sensation seeking may drink more heavily in college, in part because they select social environments in which alcohol use is encouraged. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In this paper we present some preliminary results about the coupling of shallow water equations for free surface flows and Darcy equation for groundwater flows. A suitable set of interface conditions is discussed: the Beavers and Joseph formula for the bottom stress is used. An iterative algorithm to solve the coupled problem is proposed and some numerical results are presented. 相似文献
8.
A. Yu. Luchka 《Cybernetics and Systems Analysis》2003,39(6):880-888
A modified variational-gradient method is proposed and substantiated for quasilinear operator equations in a Hilbert space. 相似文献
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During the day, there are considerable variations in the climatic factors prevailing in these regions. This is especially so during the 24-hour daily cycle of the long, hot and dry summer (mid-May to midOctober). Such climatic conditions have had a considerable impact on the daily living pattern of family life in the same season, particularly in the urban areas. During the same 24-hour cycle, they have compelled the inhabitants to shift their living activities both vertically in section and horizontally in plan; they do this in pursuit of more acceptable, if not, desirable internal thermal environmental ambience. 相似文献
10.
农业重组微生物生物安全研究进展 总被引:2,自引:2,他引:0
综述了近年来农业重组微生物的研究现状和进展 ,详细介绍农业重组微生物环境释放的监控方法以及对环境的冲击作用 ,对一些有关生物安全研究的热点问题进行了探讨 相似文献