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971.
The study concerns 124 alcoholics compulsorily committed to a locked ward at Runnagården, a coercive treatment setting in mid-Sweden. Three groups are compared: 57 patients were admitted before and 29 were admitted after the implementation of an introductory Alcoholics Anonymous-oriented program on the ward. Another 38 patients were admitted after the changes in legislation, which resulted in a longer duration of compulsory care. The groups were compared as to the number of days spent on the locked unit and the number of times they absconded. With the implementation of the program, a significant reduction was observed in the time needed on the locked ward, while the number of abscondence incidents showed a weaker tendency to decrease. After the legislative changes were made, the same factors increased. Multivariate regression was used to check confounding background factors. In conclusion, the introduction of an Alcoholics Anonymous-oriented program in a coercive treatment setting reduced the time spent on a locked ward without increasing the number of times patients absconded. Increase in length of coercion increased both the time spent at the locked ward and the number of times absconded.  相似文献   
972.
The U.S. Environmental Protection Agency (USEPA) guidelines for cancer risk assessment recognize that some chemical carcinogens may have a site-specific mode of action (MOA) involving mutation and cell-killing-induced hyperplasia. The guidelines recommend that for such dual MOA (DMOA) carcinogens, judgment should be used to compare and assess results using separate "linear" (genotoxic) versus "nonlinear" (nongenotoxic) approaches to low-level risk extrapolation. Because the guidelines allow this only when evidence supports reliable risk extrapolation using a validated mechanistic model, they effectively prevent addressing MOA uncertainty when data do not fully validate such a model but otherwise clearly support a DMOA. An adjustment-factor approach is proposed to address this gap, analogous to reference-dose procedures used for classic toxicity endpoints. By this method, even when a "nonlinear" toxicokinetic model cannot be fully validated, the effect of DMOA uncertainty on low-dose risk can be addressed. Application of the proposed approach was illustrated for the case of risk extrapolation from bioassay data on rat nasal tumors induced by chronic lifetime exposure to naphthalene. Bioassay data, toxicokinetic data, and pharmacokinetic analyses were determined to indicate that naphthalene is almost certainly a DMOA carcinogen. Plausibility bounds on rat-tumor-type-specific DMOA-related uncertainty were obtained using a mechanistic two-stage cancer risk model adapted to reflect the empirical link between genotoxic and cytotoxic effects of the most potent identified genotoxic naphthalene metabolites, 1,2- and 1,4-naphthoquinone. Bound-specific adjustment factors were then used to reduce naphthalene risk estimated by linear extrapolation (under the default genotoxic MOA assumption), to account for the DMOA exhibited by this compound.  相似文献   
973.
Much of the research on globalization conceives of the global economy as structured by networks among places, while separately organizational research has examined the role of networks among firms in structuring competition, collaboration, and cooperation. In both cases, position and centrality within the network confers certain advantages and disadvantages, the distribution of which defines a hierarchy. In this article, I explore the idea of dual networks of world cities and firms, then use Breiger's approach to define two such networks: one among 313 world cities, another among 100 advanced producer service firms. Comparison of the degree of inequality in the hierarchies implied by these networks suggest that world city hierarchies are steeper than firm hierarchies (that is there is greater inequality among cities). Thus, even under conditions of footloose global capitalism, place still matters: where a producer is located has more impact than who provides support services.  相似文献   
974.
This paper examines the relationship between assimilation and discriminatory practices encountered by Hispanic-Americans. Theories of intergroup relations have typically assumed that as members of minority ethnic groups assimilate to a dominant group, they perceive and experience lower degrees of discrimination directed against them. In reviewing theories of majority–minority relations, we have called this the “assimilationist” model. This view has been opposed by some scholars who argue that as minority ethnics assimilate and become more knowledgeable of the larger society, they perceive and experience higher levels of discrimination against them and their group. We have termed this the “conflict model” of interethnic relations. Using data from the 2002 National Survey of Latinos, conducted by the Pew Hispanic Center, we test opposing hypotheses based on these two models. Our findings, while exploratory, largely support the assimilationist model, with a few contradictory results. We discuss these findings and their implications for understanding the current situation of Hispanics in the United States.  相似文献   
975.
The success of the Global Polio Eradication Initiative promises to bring large benefits, including sustained improvements in quality of life (i.e., cases of paralytic disease and deaths avoided) and costs saved from cessation of vaccination. Obtaining and maintaining these benefits requires that policymakers manage the transition from the current massive use of oral poliovirus vaccine (OPV) to a world without OPV and free of the risks of potential future reintroductions of live polioviruses. This article describes the analytical journey that began in 2001 with a retrospective case study on polio risk management and led to development of dynamic integrated risk, economic, and decision analysis tools to inform global policies for managing the risks of polio. This analytical journey has provided several key insights and lessons learned that will be useful to future analysts involved in similar complex decision-making processes.  相似文献   
976.
该文在 1 997年的中国投入产出表的基础上作适当修改 ,编制出信息产业投入产出表 ,据此建立模型并计算出带动度和带动度系数。通过对信息产业进行研究 ,该文认为信息产业已成为国民经济的第二主导产业 ,对国民经济其他各部门总产品变动的影响很大 ,而且还有着很大的发展空间  相似文献   
977.
Empowerment has become a widely used management term in the last decade or so, though, in practical terms, it shares the ambiguity of its predecessors in the HRM tradition. This paper sets out to unravel the web of meaning surrounding empowerment to show what a contested concept it is, and hence why its application in organizational settings is fraught with misunderstanding and tension. It does so by taking an approach that contributes to the examination of HRM discourse and management rhetoric. To demonstrate the ambiguity of empowerment as a concept, the paper reviews the various ways in which the term has been used across non-management disciplines (women, minority groups, education, community care, politics), culminating with a review of the use of empowerment in contemporary management theory. The paper concludes that organizations and managers have chosen to coin a phrase which is open to different, sometimes contradictory, meanings and which, when applied, evokes both subjective attitudes and objective behaviour, means different things in varying contexts, and is affected fundamentally by individual differences in perception and experience. Unless organizations offer clear operational definitions when using empowerment, instead of purely acquiescing to a vague and seductive version of the concept, they are abdicating responsibility for the unpredictable consequences that result.  相似文献   
978.
This study analyses critically the latest existence of non-monetary accounting: its uses today, its advantages and disadvantages, and the inevitable trends of a move away from total reliance on monetary accounting, especially now with the development of integrated information systems in modern enterprises.  相似文献   
979.
980.
i , i = 1, 2, ..., k be k independent exponential populations with different unknown location parameters θ i , i = 1, 2, ..., k and common known scale parameter σ. Let Y i denote the smallest observation based on a random sample of size n from the i-th population. Suppose a subset of the given k population is selected using the subset selection procedure according to which the population π i is selected iff Y i Y (1)d, where Y (1) is the largest of the Y i 's and d is some suitable constant. The estimation of the location parameters associated with the selected populations is considered for the squared error loss. It is observed that the natural estimator dominates the unbiased estimator. It is also shown that the natural estimator itself is inadmissible and a class of improved estimators that dominate the natural estimator is obtained. The improved estimators are consistent and their risks are shown to be O(kn −2). As a special case, we obtain the coresponding results for the estimation of θ(1), the parameter associated with Y (1). Received: January 6, 1998; revised version: July 11, 2000  相似文献   
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