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11.
This study investigated the role of odorant cues used during host‐habitat location by the generalist parasitoid, Nasonia vitripennis Walker. Nasonia vitripennis is a common parasitoid of Dipteran pupae found in association with decaying carrion. Behavioral assays were used to investigate the host‐habitat searching behavior under different scenarios. First, we demonstrated N. vitripennis to be significantly attracted toward odorant cues associated with decaying meat. The biological activity of nine of the volatile molecules constituting the odor of decaying meat was tested on the searching behavior of parasitoid females through two complementary chemoecological approaches: electroantennography (EAG) and olfactometry bioassays. Butanoic acid and butan‐1‐ol elicited high olfactory responses, but no attraction was induced by these two chemicals. Behavioral assays showed that, among the VOCs tested, methyldisulfanylmethane (DMDS) was the only volatile chemical to induce attraction in N. vitripennis.  相似文献   
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Most forensic studies are focused on Diptera pattern colonization while neglecting Coleoptera succession. So far, little information is available on the postmortem colonization by beetles and the decomposition process they initiate under temperate biogeoclimatic countries. These beetles have, however, been referred to as being part of the entomofaunal colonization of a dead body. Forensic entomologists need increased databases detailing the distribution, ecology, and phenology of necrophagous insects, including staphylinids (Coleoptera, Staphylinidae). While pig carcasses are commonly used in forensic entomology studies to surrogate human decomposition and to investigate the entomofaunal succession, very few works have been conducted in Europe on large carcasses. Our work reports the monitoring of the presence of adult rove beetles (Coleoptera, Staphylinidae) on decaying pig carcasses in a forest biotope during four seasons (spring, summer, fall, and winter). A total of 23 genera comprising 60 species of rove beetles were collected from pig carcasses.  相似文献   
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ABSTRACT

This article uses Transaction Cost Economics (TCE) to help characterize, explain, and ultimately reduce the cost growth that plagues many of today's major investments in military capabilities. There is mounting evidence of a systematic bias in initial cost estimates of new weapon systems purchased by the U.S. military. Unrealistically low cost estimates result in cost overruns. Fixing cost overruns can substantially impact public budgets and military readiness. Cost estimates serve a dual function: first, as an integral part of the decision-making process to evaluate military purchases/investments, and second, as a baseline for future defense budgets. In the first case, underestimating costs can result in too many new weapon program starts and excessive investments in those systems. In the second case, unrealistically low cost estimates result in overly optimistic budgets. Budgets planned on the basis of optimistic cost estimates create the illusion of more resources available than actually exist. Two factors are often blamed for unrealistically low cost estimates: bad incentives (psychological and political-economic explanations), and bad forecasts (methodological explanations). While briefly exploring the former, the focus of this study is on cost estimating methodology. Conventional public cost estimating techniques focus on the production costs of public purchases (input costs, learning curves, economies of scale and scope, etc.). The goal of this article is to improve cost estimates by expanding conventional cost estimating methodology to include TCE considerations. The primary insight of TCE is that correctly forecasting economic production costs of government purchases or acquisitions is necessary, but not sufficient. TCE emphasizes another set of costs—coordination and motivation costs (search and information costs; decision, contracting, and incentive costs; measurement, monitoring, and enforcement costs, etc.). This study encourages public officials and cost analysts to capture these costs and to understand key characteristics of public-private transactions (uncertainty, complexity, frequency, asset specificity, and market contestability) to generate more complete and reliable cost estimates and improve public sector purchases.  相似文献   
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This paper draws its conclusions from a multidisciplinary studyof the refugee determination process in Canada, the aim of whichwas to examine the strengths and weaknesses of the system andto explore means of improving it through an in-depth analysisof the diversity of attitudes and perceptions of different actorsinvolved in the process. The basic hypothesis is that the legitimacyof the action of the Immigration and Refugee Board (hereafterIRB) is challenged because of a series of disagreements on theway it operates. Using interviews with former Board members,as well as with other professional actors of the system (lawyers,NGO workers, interpreters, health professionals), we try tounderstand better the parameters of the problems facing theIRB on three sets of issues: the appointment and renewal ofBoard members; the relationships between Board members withinthe IRB; the evaluation of the evidence by Board members. Allissues relate mainly to the principles of independence and impartialityof the IRB, as an expert administrative tribunal. In particular,using the idea of ‘critical space’ as a conceptualframework, this study tries to ascertain more precisely howcritical spaces within the IRB were being used in order to fostera common culture of independence and impartiality within theinstitution, or not. This study covers the period 1989-2002:it signals reforms accomplished since and suggests more meansfor improvement.  相似文献   
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The International Society for Forensic Genetics (ISFG) has established a Paternity Testing Commission (PTC) with the purpose of formulating international recommendations concerning genetic investigations in paternity testing. The PTC recommends that paternity testing be performed in accordance with the ISO 17025 standards. The ISO 17025 standards are general standards for testing laboratories and the PTC offers explanations and recommendations concerning selected areas of special importance to paternity testing.  相似文献   
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Flies of the Calliphoridae Family are the most forensically important insects because of their abundance on the decedent during the first minutes following death. Necrophagous insects are attracted at a distance by a decomposing body, through the use of volatile chemical cues. We tested the possible attractive role of some volatile organic chemicals (VOCs) released by decaying cadavers, on male and female of Lucilia sericata Meigen (Diptera: Calliphoridae). Two complementary approaches were used. Electroantennography (EAG) allowed identifying the semiochemicals that are detected by the olfactory system of L. sericata. Dose-response tests with EAG showed that dimethyl disulfide (DMDS) and butan-1-ol elicited the highest responses. Behavioral assays showed that, among the VOCs tested, DMDS and butan-1-ol are attractive for L. sericata, while the other VOCs are repulsive or do not cause any behavior. Our results may have potential implications in a better understanding of attractiveness of blowflies toward a corpse.  相似文献   
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Gelineau  Francois; Belanger  Eric 《Publius》2005,35(3):407-424
Are federal incumbents punished for national and/or provincialeconomic performance, and are provincial incumbents held accountablefor the state of the provincial and/or national economy? Usinga pooled cross-sectional time-series analysis of electoral resultsand macroeconomic data for 1953–2001, this article exploresthe extent to which provincial and federal incumbents in Canadianelections are affected more by national or provincial economicconditions. The results of the analysis suggest that federalincumbents would not gain many votes by claiming credit forthe economic prosperity of any particular province when, onaverage, national economic conditions are deteriorating. Theresults further suggest that provincial incumbents are not heldaccountable for economic conditions in their provinces, butare rather punished for national economic deterioration whenthe incumbent federal party is of the same partisan family.  相似文献   
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