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71.
Silphids in urban forests: Diversity and function   总被引:2,自引:0,他引:2  
Wolf  Jordan M.  Gibbs  James P. 《Urban Ecosystems》2004,7(4):371-384
Many ecologists have examined the process of how urbanization reduces biological diversity but rarely have its ecological consequences been assessed. We studied forest-dwelling burying beetles (Coleoptera: Silphidae)—a guild of insects that requires carrion to complete their life cycles—along an urban-rural gradient of land use in Maryland. Our objective was to determine how forest fragmentation associated with urbanization affects (1) beetle community diversity and structure and (2) the ecological function provided by these insects, that is, decomposition of vertebrate carcasses. Forest fragmentation strongly reduced burying beetle diversity and abundance, and did so far more pervasively than urbanization of the surrounding landscape. The likelihood that beetles interred experimental baits was a direct, positive function of burying beetle diversity. We conclude that loss of burying beetle diversity resulting from forest fragmentation could have important ecological consequences in urban forests.  相似文献   
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We re-evaluate Andreu and Spanos's findings in favour of trend stationarity by considering the extended Nelson-Plosser data set. This expanded (to 1988) data set includes a period of rather different behaviour compared with the original Nelson-Plosser data used by Andreou and Spanos. We find that Andreou and Spanos's models (with only minor adjustments) exhibit remarable stability over this extended period, and indicate that their conclusions are more robust than they have shown.  相似文献   
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The collapse of the USSR was accompanied by transformation of the South Caucasian latent ethnopolitical conflicts into local wars. Today the situation in the area of the conflicts is “neither war, nor peace”. Three unresolved conflicts of the South Caucasus can be considered as one of the most serious obstacles for establishing a regional security system.The article gives the general characteristics of these conflicts, the trends of their development, taking into account the time factor, and analyzes the behavioral models of the main players – de jure recognized and unrecognized de facto states of the South Caucasus. The basic objective of the main players should be to keep the situation on a level preventing the resumption of the armed conflicts. The attempts of forced resolution of the conflicts are fraught with destabilization of the situation not only in the area of any of these conflicts but in the whole region.  相似文献   
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Using findings from a study of the world of the wives of professional athletes, this article explores the complex motivations for and displays of trust, rapport, and group acceptance during ethnographic research. Episodic exchanges between a male ethnographer and female collaborators revealed subtle issues of gender and perceived relative worth. This article proposes the outsider strategy of “muted masculinity” as a means of exploring ethnographic issues in which the boundaries between insiders and outsiders are uncertain.  相似文献   
78.
Trade-Offs Between Formal Home Health Care and Informal Family CareGiving   总被引:2,自引:2,他引:0  
Using 1994 National Long Term Care Survey data, we estimated logistic regressions of formal and informal home health care use and hours. Home health care use and intensity were differentially impacted by chronic conditions, are higher for Medicaid enrollees and rural or small town residents, but lower for HMO enrollees. Decreases in the probability of home health care use increased informal instrumental activities of daily living (IADL) support four hours and decreased informal activities of daily living (ADL) support eight hours weekly. IADL caregiving substituted for formal care, but ADL caregiving declined with reductions in formal care. Public policy reducing formal home health care access may reduce informal ADL caregiving and increase informal IADL caregiving, producing net declines in support.  相似文献   
79.
Starting with its early twentieth century origins, the development of Labor Economics is traced to the present. We describe an intellectual revolution in which an earlier tra-dition that focused primarily on the institution of the labor union has been replaced by a perspective that emphasizes the various roles played by labor markets in an eco-nomic system. That earlier tradition contained very significant ideological elements, whereas its successor deals much more with the world of ideas. In the course of the debate, which still continues, ideas triumphed over ideology and created modern Labor Economics.  相似文献   
80.
This paper proposes a developmental framework for foster parents and outlines four distinct growth stages. Such a framework can be of value to program administrators who are required to assess foster parent development during the crucial matching process. To draw a distinction between each developmental stage, specific instrumental tasks and indicators are outlined.  相似文献   
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