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51.
Numerous laboratory experiments have investigated the performance of several processes for providing public goods through voluntary contributions. This research has been able to identify features of the institution or environment which are reliably likely to produce outcomes “close” to the free riding outcome or “substantially” greater than the pessimistic prediction of standard models. One such feature is the “marginal per-capita return” (MPCR) from the public good. Various authors have altered MPCR between groups or for an entire group at the same time. The experiments reported here address a different question, “What would happen if, within a group, some persons faced a ‘high’ MPCR while others faced a ‘low’ MPCR?”  相似文献   
52.
Data from a large sample of late adolescents was used to examine associations between family relationships (reported closeness to parents and siblings) and perceived social competence. Significant positive relationships were found between family bonds and the social competence measures, which included social self-esteem, instrumentality, expressiveness, shyness, and degree of satisfaction/ease in same- and opposite-sex peer relationships. There was no evidence of differential effects of sibling versus parent relationships upon adolescent social competence.This project was supported by NIMH Grant 5 R01 MH34570.Received Ph.D. from Northwestern University.  相似文献   
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Mitochondrial DNA (mtDNA) analysis of forensic samples typically is performed when the quantity and quality of DNA are insufficient for nuclear DNA analysis or when maternal relatives may be the only reference source. Many of the steps required in the analytical process are both lengthy and labor intensive. Therefore, improvements in the process that reduce labor without compromising the quality of the data are desirable. The current procedure requires purification of the amplicons by centrifugal filtration after PCR and prior to cycle sequencing. Because this method requires several manipulations to perform, alternate cleanup procedures were investigated. These include the use of 1) Qiagen QlAquick PCR Purification columns, 2) Concert Rapid PCR Purification columns, and 3) ExoSAP-IT reagent. When the yield of purified amplicons, quality of the sequence profile, and ease of assay were evaluated, the use of ExoSAP-IT reagent for post-amplification purification was chosen to replace the filtration method.  相似文献   
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The study was performed to distinguish fatal from non-fatal blood concentrations of morphine. For this purpose, blood levels of free morphine and total morphine (free morphine plus morphine conjugates) in 207 cases of heroin-related deaths were compared to those in 27 drivers surviving opiate intoxication. The majority of both survivors and non-survivors were found to show a concomitant use of depressants including alcohol or stimulants. Blood morphine levels in both groups varied widely, with a large area of overlap between survivors (free morphine: 0-128 ng/ml, total morphine: 10-2,110 ng/ml) and non-survivors (free morphine: 0-2,800 ng/ml, total morphine: 33-5,000 ng/ml). Five (18.5%) survivors and 87 (42.0%) non-survivors exhibit intoxication only by morphine. In these cases, too, both groups overlapped (survivors-free morphine: 28-93 ng/ml, total morphine: 230-1,451 ng/ml; non-survivors-free morphine: 0-2,800 ng/ml, total morphine: 119-4,660 ng/ml). Although the blood levels of free or total morphine do not allow a reliable prediction of survival versus non-survival, the ratio of free/total morphine may be a criterion to distinguish lethal versus survived intoxication. The mean of the ratio of free to total morphine for all lethal cases (N=207) was 0.293, for those that survived (N=27) 0.135, in cases of intoxication only by morphine 0.250 (N=87) and 0.080 (N=5), respectively. Applying a cut-off of 0.12 for free/total morphine and performing ROC analyses, fatal outcome can be predicted in 80% of the cases correctly, whereas 16% of the survivors were classified as dead. Nevertheless, in this study, all cases with a blood concentration of 200 ng/ml and more of free morphine displayed a fatal outcome.  相似文献   
57.
Over the past decade, clear evidence has been produced showing that effective constituency campaigning in British general elections can lead to better electoral performance. This evidence has challenged the received wisdom that only national campaigning is significant and that efforts at local level are meaningless rituals. Denver et al. have focused on the role of the national parties in strengthening local campaigns in target seats; Seyd and Whiteley, by contrast, have stressed the importance of local party membership. This article attempts to assess the relative electoral impact of national party co-ordination and constituency party membership and suggests that the impact of these two factors varies by party.  相似文献   
58.
Networks of local government support organisations (LGSOs) are critical to successful intergovernmental relations and effective local governance in democratic societies. Bulgaria had no such network of municipal associations when it began the transition from communist rule in the early 1990s. Using US and other external technical assistance, Bulgaria over the next decade overcame the impediments to collective action and established what appears to be an effective and sustainable system to back up its cities and towns. Important factors in mobilising support included a long‐term focus on institutional development, non‐partisanship, flexibility in implementation and a pragmatic orientation that focused on learning by doing. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
59.
In the wake of welfare reform efforts, alliances between governments and charities, and public preoccupation with “social capital,” it is useful to understand how welfare payments interact with charitable giving. Using Consumer Expenditure Survey data from the first quarter of 1999, this article estimates the impacts on charitable giving by individuals from receipt of welfare payments, as well as income, wealth, and a number of demographic variables. The data analysis suggests that charity is negatively associated with welfare receipt, while wealth, income, and age have positive impacts on giving. These findings have significant implications for public policy and nonprofit management.  相似文献   
60.
A substantial literature over the years has focused on the relationship between political alienation and ideology. Much of this research contends that conservatives are more alienated than liberals because philosophically they believe that the best government is that which governs least. A close reading of the literature, however, reveals little consistency in the empirical findings. Survey data from Norway, Sweden, and the United States are used to provide a more extensive and consistent test of the hypothesis. Ideology is defined as both left/right self-identification and policy preference on economic and "new political" issues. The evidence reveals that in Scandinavia higher levels of alienation are found among conservatives, whereas in the US the left has been consistently more alienated, except on "new politics" issues. The discrepancy between the citizen's preferred ideological orientation and that which the public perceives the government to take, is used to explain the different findings for the three countries and the shifts in the relationship between ideology and alienation across time.  相似文献   
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