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11.

How robust is the welfare state when confronting open borders? To answer that question, we develop an evolutionary game-theoretic model combined with an ingroup–outgroup model. The simulations reveal that welfare states in general will transform into low-welfare societies unless the societies in time generate a sufficiently large amount of social recognition of the reciprocators in such a crisis. The recognition implies that the “always cooperators” in favour of supportive policies towards free riders need to step down and hand over privileges to those willing to reciprocate, namely the “willing punishers”. The open-border society is modelled by letting a small amount of random types enter the society each year. Interestingly, it is not the defectors who compromise high-welfare societies. Instead, it is the excessive presence of cooperators who crowd out the reciprocators, thus making society increasingly vulnerable to free riding. This accentuates the need for timely recognition and actions against the risk of moving towards a low-welfare society.

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THE advent of the year of the dragon finds Yiwu-a famous manufacturing and distribution center for small commodities-full of good cheer and anticipation for the coming year.  相似文献   
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This paper presents an overview of the organisation and the results of the collaborative exercises (CE) of the European DNA Profiling (EDNAP) Group's mitochondrial DNA population database project (EMPOP). The aim of the collaborative exercises was to determine whether uniformity of mtDNA sequencing results could be achieved among different laboratories. These were asked to sequence either the complete mtDNA control region or the two hypervariable regions HVI (16024-16365) and HVII (73-340) from DNA extracts, buccal swabs or bloodstains, proceeding in accordance with the protocol and strategies used in each individual laboratory. The results of the collaborative exercises were employed to identify possible sources of errors that could arise during the analysis and interpretation of mtDNA profiles. These findings were taken as a basis to tentatively make suitable arrangements for the construction of a high quality mtDNA database. One hundred fifty mtDNA profiles were submitted to the evaluating laboratory, and disaccording profiles were classified into four groups corresponding to the source of error: clerical errors, sample mix-ups, contaminations and discrepancies with respect to the mtDNA nomenclature. Overall, 14 disaccording haplotypes (16 individual errors) were observed. The errors included 10 clerical errors, 3 interpretation problems, 2 cases of sample mix-up and 1 case of point heteroplasmic mixture, where the 2 sequencing reactions brought inconsistent base calls. This corresponds to an error rate of 10.7% in a virtual mtDNA database consisting of the collaborative exercise results. However, this estimate is still conservative compared to conclusions drawn by authors of meanwhile numerous publications critically reviewing published mtDNA population databases. Our results and earlier published concerns strongly emphasize the need for appropriate safety regulations when mtDNA profiles are compiled for database purposes in order to accomplish the high standard required for mtDNA databases that are used in the forensic context.  相似文献   
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In this article, we discuss how farm conversions to wildlife habitats result in the reconfiguration of spatial and social relations on white-owned commercial farms in the Karoo region of the Eastern Cape in South Africa. Farmers and landowners justify such conversions stressing economic and ecological rationales. We illustrate how conversions are (also) a reaction to post-apartheid land reform and labour legislation policies, which white farmers and landowners perceive as a serious threat. They seek to legitimate their position in society and reassert their place on the land by claiming a new role as nature conservationists. We argue that game farms should be interpreted as economically and politically contested spaces for three reasons: (1) whereas landowners present the farm workers' displacement from game farms as the unintended by-product of a changing rural economy, the creation of ‘pristine’ wilderness seems designed to empty the land of farm dwellers who may lay claim to the land; (2) game farms further disconnect the historically developed links between farm dwellers and farms, denying them a place of residence and a base for multiple livelihood strategies; (3) this way the conversion process deepens farm dwellers' experiences of dispossession and challenges their sense of belonging. Game fences effectively define farm workers and dwellers as people out of place. These dynamics contrast government reform policies aimed at addressing historical injustices and protecting farm dwellers' tenure security.  相似文献   
15.
A total of 300 motorists were recruited at public places to answer a self-report questionnaire on a new community-based intervention to enhance road safety. The intervention consisted of a speed-displaying device that was mounted next to the road and was visible to both motorists and the public. The device gives feedback about the current speed of the motorist. The majority of motorists believed these devices influenced compliance with the speed limit. They indicated they approached locations with these devices more slowly than similar locations without such devices. Moreover, they slowed down if they were going faster than the speed limit. They also said that their reaction to the devices was not influenced by whether they were driving in a community where they had friends or in a community where nobody knew them. These results were consistent across gender, age, levels of education, and professions.  相似文献   
16.
The psychoactive properties of N,N-dimethyltryptamine (DMT) 1a are known to induce altered states of consciousness in humans. This particular attribute attracts great interest from a variety of scientific and also clandestine communities. Our recent research has confirmed that DMT reacts with dichloromethane (DCM), either as a result of work-up or storage to give a quaternary N-chloromethyl ammonium salt 2a. Furthermore, this was observed to undergo rearrangement during analysis using gas chromatography-mass spectrometry (GC-MS) with products including 3-(2-chloroethyl)indole 3 and 2-methyltetrahydro-beta-carboline 4 (2-Me-THBC). This study further investigates this so far unexplored area of solvent interactions by the exposure of DMT to other halogenated solvents including dibromomethane and 1,2-dichloroethane (DCE). The N-bromomethyl- and N-chloroethyl quaternary ammonium derivatives were subsequently characterised by ion trap GC-MS in electron and chemical ionisation tandem MS mode and by NMR spectroscopy. The DCE-derived derivative formed at least six rearrangement products in the total ion chromatogram. Identification of mass spectrometry generated by-products was verified by conventional or microwave-accelerated synthesis. The use of deuterated DCM and deuterated DMT 1b provided insights into the mechanism of the rearrangements. The presence of potentially characteristic marker molecules may allow the identification of solvents used during the manufacture of controlled substances, which is often neglected since these are considered inert.  相似文献   
17.
Claims of amnesia are frequently raised in criminal and civil cases. There is a consensus in the legal community that amnesia is easily faked and practically impossible to disprove, and that many who claim to be amnesic are malingering. The present studies compared, on a variety of memory tasks, subjects instructed to simulate amnesia with subjects who had memory impairments due to brain damage. The simulators displayed patterns of performance different from those of memory-impaired subjects. These results suggest that lay-people have inaccurate beliefs about the cognitive features of amnesia, and do not distinguish among etiologically distinct amnestic disorders. Tasks that exploit lay-people's inaccurate beliefs about amnesia appear promising for the detection of malingering.  相似文献   
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An Economic Analysis of Flexible Permit Trading in the Kyoto Protocol   总被引:2,自引:0,他引:2  
This paper evaluates the relative gains from augmenting or restricting several of the flexibility mechanisms of the Kyoto Protocol. A nonlinear programming model of international emissions trading is used to assess the net benefits of extending trading across time periods and across countries (Joint Implementation), and including the developing world (Clean Development Mechanism). The effect of limiting permit purchases (supplementarity) is also evaluated. The analysis is intended to help guide further climate negotiations by identifying flexibility mechanisms that contribute the most to enhancing the gains from greenhouse gas mitigation and identifying restrictions that detract the most from these gains.  相似文献   
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