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901.
本文认为:"消极的社会保障"是指主要发挥"保障基本生活,保持社会稳定"功能的社会保障,"积极的社会保障"则是指在发挥前者功能的基础上进一步发挥"增加人民福祉,促进社会和谐"功能的社会保障.文章从发展阶段、社会公平、制度建设的角度提出改善民生必须特别重视加强社会保障体系的建设,实现从"消极的社会保障"向"积极的社会保障"的战略性转变.  相似文献   
902.
This study extends previous research by proposing an integrative model that examines the mediating processes underlying the relationship between leader support and employee OCB. Data were collected from 323 employees and their immediate supervisors in seven Taiwanese companies. Results showed that supervisor support influenced the employees’ OCB indirectly through two cognitive processes (job satisfaction and person–organization fit) and one affective process(job tension).  相似文献   
903.
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   
904.
不规范何以立,不规范难创新,默顿提出普遍性、公有性、无私利性和有条理的怀疑性构成了现代科学规范,科研失范行为一般指科研工作者在从事科研工作中为了实现自己的利益目标而违背科学界和学术界所公认的科学研究道德规范的行为,本文对各种科研示范行为进行分类,从政治、经济、体制等方面深度分析了科研失范的诱发原因,并有针对性的提出若干防范对策,从而捍卫科学殿堂的圣洁性。  相似文献   
905.
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   
906.
907.
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   
908.
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   
909.
Invertebrates are valuable models for increasing our understanding of the effects of ethanol on the nervous system, but most studies on invertebrates and ethanol have focused on the effects of ethanol on locomotor behavior. In this work we investigate the influence of an acute dose of ethanol on appetitive olfactory learning in the honey bee (Apis mellifera), a model system for learning and memory. Adult worker honey bees were fed a range of doses (2.5%, 5%, 10%, or 25%) of ethanol and then conditioned to associate an odor with a sucrose reward using either a simple or differential conditioning paradigm. Consumption of ethanol before conditioning significantly reduced both the rate of acquisition and the asymptotic strength of the association. Honey bees also exhibited a dose dependent reduction in arousal/attention during conditioning. Consumption of ethanol after conditioning did not affect recall 24h later. The observed deficits in acquisition were not due to the affect of ethanol on gustatory sensitivity or motor function. However, honey bees given higher doses of ethanol had difficulty discriminating amongst different odors suggesting that ethanol consumption influences olfactory processing. Taken together, these results demonstrate that an acute dose of ethanol affects appetitive learning and olfactory perception in the honey bee.  相似文献   
910.
The DFC Intelligence predicts worldwide online game revenues will reach $9.8 billion by 2009, making online gaming a mainstream recreational activity. Understanding online game player personality traits is therefore important. This study researches the relationship between personality traits and life satisfaction in online game players. Taipei, Taiwan, is the study location, with questionnaire surveys conducted in cyber cafe shops. Multiple regression analysis studies the causal relationship between personality traits and life satisfaction in online game players. The result shows that neuroticism has significant negative influence on life satisfaction. Both openness and conscientiousness have significant positive influence on life satisfaction. Finally, implications for leisure practice and further research are discussed.  相似文献   
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