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991.
Li‐Chen Hsu 《决策行为杂志》2008,21(2):151-167
Experiments on three two‐person threshold public good provision games, namely, the simultaneous, sequential, and dictator games, are conducted to explore the motives behind giving. Players who move simultaneously are endowed with equal bargaining power, and players who move first are endowed with more bargaining power than players who move subsequently. Dictators are indubitably endowed with complete bargaining power. Since the differences between the bargaining powers of two players increase from the simultaneous to the sequential to the dictator game, comparisons among games allow us to trace whether the contribution behavior is motivated by fairness or is simply due to the strategic concern. The experimental evidence shows that the strategic concern explains the overall contribution behavior better than the motive of fairness. However, in the final round 26% of the dictators share the threshold evenly with their opponents, suggesting that some subjects do play fairly. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
992.
在中央领导的亲切关怀下,在国家宗教事务局的关心帮助下,中国道教协会会所及中国道教学院校舍建设工程已完成了前期各项准备工作,于2008年11月20日上午在北京举行奠基仪式. 相似文献
993.
Li Liu 《Journal of community & applied social psychology》2008,18(3):233-252
This study explores the social representation of quality of life (QOL) in the Chinese socio‐cultural context. The data were collected by 16 open‐ended individual interviews. The study shows that the social representation of QOL embedded deeply in the collective memory of Chinese society is generated from, and organized around, the central thema of ‘having’/‘being’. ‘Having’ and ‘being’ are both antinomic and dialogically interdependent. ‘Having’ gives priority to how subject instrumentalizes object as resources to be possessed and consumed. It is manifested in the possessions of money, food, housing and car. The possessions are not only simply the material things but also the objects of symbolic significance. ‘Being’ prioritizes the authentic relationship between subject and object. It is manifested in rootedness, connectedness, participation and freedom. These provide a sense of belonging, commitment, direction and purpose and involve the establishment and maintenance of the union between the self and others, and between the individual and the outside world. On the other hand, neither ‘having’ nor ‘being’ exists in its pure form. Rather, they co‐exist dynamically, in rival or complementary ways, and each calls the possibility of the other into play. It is the synthesis of opposites between ‘having’ and ‘being’ that the social representation of QOL is generated and structured. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
994.
995.
Wang Z Pan Y Li W Jiang H Chatzimanolis L Chang J Gong Z Liu L 《Learning & memory (Cold Spring Harbor, N.Y.)》2008,15(3):133-142
The role of the foraging (for) gene, which encodes a cyclic guanosine-3',5'-monophosphate (cGMP)-dependent protein kinase (PKG), in food-search behavior in Drosophila has been intensively studied. However, its functions in other complex behaviors have not been well-characterized. Here, we show experimentally in Drosophila that the for gene is required in the operant visual learning paradigm. Visual pattern memory was normal in a natural variant rover (for(R)) but was impaired in another natural variant sitter (for(S)), which has a lower PKG level. Memory defects in for(S) flies could be rescued by either constitutive or adult-limited expression of for in the fan-shaped body. Interestingly, we showed that such rescue also occurred when for was expressed in the ellipsoid body. Additionally, expression of for in the fifth layer of the fan-shaped body restored sufficient memory for the pattern parameter "elevation" but not for "contour orientation," whereas expression of for in the ellipsoid body restored sufficient memory for both parameters. Our study defines a Drosophila model for further understanding the role of cGMP-PKG signaling in associative learning/memory and the neural circuit underlying this for-dependent visual pattern memory. 相似文献
996.
Liu YF Chen HI Yu L Kuo YM Wu FS Chuang JI Liao PC Jen CJ 《Neurobiology of learning and memory》2008,90(1):81-89
Cognitive functions usually involve various synaptic proteins and neurotrophic factors in the hippocampus. However, whether treadmill exercise can improve learning and memory by upregulating some of these molecules remain unraveled. To address this question, male BALB/c mice were divided into control and exercise groups, the latter group went through 4 weeks of treadmill exercise training. At the end of exercise training period, they were either tested for passive avoidance (PA) performance or sacrificed for quantifying the hippocampal levels of brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B (TrkB, the BDNF receptor), synaptotagmin (a Ca2+-dependent synaptic vesicle protein), and SNAP-25 (a presynaptic vesicular fusion protein). Our results showed that treadmill exercise training (1) increased the retention latency without affecting the fear acquisition in the PA test, (2) transiently increased the hippocampal BDNF level at 1, 2, and 4 h after the completion of exercise training, and (3) persistently increased the hippocampal protein levels of full-length TrkB, phosphorylated TrkB and synaptotagmin, but not truncated TrkB or SNAP-25. Moreover, the protein expression level of full-length TrkB or synaptotagmin was positively correlated with PA performance in mice. Finally, inhibition of TrkB signaling by K252a abolished the exercise-facilitated PA performance and upregulation of TrkB and synaptotagmin. Taken together, these data suggest that the upregulation of TrkB and synaptotagmin in the hippocampus contributes to the exercise-facilitated aversive memory. 相似文献
997.
当今,命题模态逻辑作为一种标准的形式工具,已被广泛应用于计算机科学和人工智能的各个领域.然而,与命题模态逻辑不同,通常的一阶模态逻辑语言的表达力是不充分的,这是许多重要问题背后的原因所在,这些重要问题包括:模态逻辑中没能出现与经典逻辑相媲美的赫伯兰(Herbrand)定理、非严格指称问题、同一性问题、罗素的限定摹状词理论、动态逻辑的指派表达等等.美国当代逻辑学家、证明论专家菲汀(M.C.Fitting)充分认识到通常的一阶模态逻辑表达力不充分所产生的弊端,他通过把谓词抽象引入通常的一阶模态逻辑的语形和语义,以一种极其简单和自然的形式加强了一阶模态语言的表达力,从而使上述问题迎刃而解.本文首先介绍谓词抽象的基本思想及其简史,然后重点阐述谓词抽象在模态赫伯兰定理以及其他领域的重要作用. 相似文献
998.
政治对于哲学家往往有一种难以拒斥的诱惑,在古代希腊和中国都是如此,哲学家对于政治有一种无法割舍的介入冲动.政治和哲学作为两种活动是难以割舍的一对,无论是患难与共的兄弟还是不同戴天的冤家,这在现代和当代哲学中依然是一个重要的问题. 相似文献
999.
在当今社会,各个国家经济发展中,资源在国民经济发展中的作用日益突出。由于资源本身就是处于特定社会条件之下,处于一个国家的特定的产权制度安排之中,因而,一个国家的资源产权制度安排状况,特别是所有权与经营权关系的安排状况,对于经济发展以及社会发展具有极其重要的作用和 相似文献
1000.
We used visual search to explore whether attention could be guided by Kanizsa-type subjective contours and by subjective contours induced by line ends. Unlike in previous experiments, we compared search performance with subjective contours against performance with real, luminance contours, and we had observers search for orientations or shapes produced by subjective contours, rather than searching for the presence of the contours themselves. Visual search for one orientation or shape among distractors of another orientation or shape was efficient when the items were defined by luminance contours. Search was much less efficient among items defined by Kanizsa-type subjective contours. Search remained efficient when the items were defined by subjective contours induced by line ends. The difference between Kanizsa-type subjective contour and subjective contours induced by line ends is consistent with physiological evidence suggesting that the brain mechanisms underlying the perception of these two kinds of subjective contours may be different. 相似文献