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71.
Beryllium is the strongest of the lightweight metals. Used primarily in military applications prior to the end of the Cold War, beryllium is finding new applications in many commercial products, including computers, telecommunication equipment, and consumer and automotive electronics. The use of beryllium in nondefense consumer applications is of concern because beryllium is toxic. Inhalation of beryllium dust or vapor causes a chronic lung disease in some individuals at concentrations as low as 0.01 microg/m3 in air. As beryllium enters wider commerce, it is prudent to ask what risks this might present to the general public and to workers downstream of the beryllium materials industry. We address this question by evaluating the potential for beryllium exposure from the manufacturing, use, recycle, and disposal of beryllium-containing products. Combining a market study with a qualitative exposure analysis, we determine which beryllium applications and life cycle phases have the largest exposure potential. Our analysis suggests that use and maintenance of the most common types of beryllium-containing products do not result in any obvious exposures of concern, and that maintenance activities result in greater exposures than product use. Product disposal has potential to present significant individual risks, but uncertainties concerning current and future routes of product disposal make it difficult to be definitive. Overall, additional exposure and dose-response data are needed to evaluate both the health significance of many exposure scenarios, and the adequacy of existing regulations to protect workers and the public. Although public exposures to beryllium and public awareness and concern regarding beryllium risks are currently low, beryllium risks have psychometric qualities that may lead to rapidly heightened public concern.  相似文献   
72.
To quantify the health benefits of environmental policies, economists generally require estimates of the reduced probability of illness or death. For policies that reduce exposure to carcinogenic substances, these estimates traditionally have been obtained through the linear extrapolation of experimental dose-response data to low-exposure scenarios as described in the U.S. Environmental Protection Agency's Guidelines for Carcinogen Risk Assessment (1986). In response to evolving scientific knowledge, EPA proposed revisions to the guidelines in 1996. Under the proposed revisions, dose-response relationships would not be estimated for carcinogens thought to exhibit nonlinear modes of action. Such a change in cancer-risk assessment methods and outputs will likely have serious consequences for how benefit-cost analyses of policies aimed at reducing cancer risks are conducted. Any tendency for reduced quantification of effects in environmental risk assessments, such as those contemplated in the revisions to EPA's cancer-risk assessment guidelines, impedes the ability of economic analysts to respond to increasing calls for benefit-cost analysis. This article examines the implications for benefit-cost analysis of carcinogenic exposures of the proposed changes to the 1986 Guidelines and proposes an approach for bounding dose-response relationships when no biologically based models are available. In spite of the more limited quantitative information provided in a carcinogen risk assessment under the proposed revisions to the guidelines, we argue that reasonable bounds on dose-response relationships can be estimated for low-level exposures to nonlinear carcinogens. This approach yields estimates of reduced illness for use in a benefit-cost analysis while incorporating evidence of nonlinearities in the dose-response relationship. As an illustration, the bounding approach is applied to the case of chloroform exposure.  相似文献   
73.
Assessing reoffense risk with juvenile sexual offenders   总被引:1,自引:0,他引:1  
This article summarizes a two-year study of juvenile sexual offenders in Washington. Both community-based and institution-based treatment programs were evaluated. A typical profile of the juvenile sexual offender is offered, as well as recidivism data from a mean 20-month follow-up period.  相似文献   
74.
Racial differences in urban neighboring   总被引:2,自引:0,他引:2  
Despite mixed expectations generated by existing theories and evidence, this analysis documents clear racial differences in urban neighboring behavior. Using data from a survey of Nashville, Tennessee, residents, we show that blacks interact with their neighbors more often than whites do, and in a greater variety of ways. The only noteworthy similarity between the two groups is the positive impact of neighboring on feelings of community affect. Overall, our results support the view that neighbor relations — like other kinds of informal participation — have helped blacks cope with constrained social opportunities and provided them with access to resources unavailable through formal institutional channels.Revised version of a paper presented at the annual meeting of the American Sociological Association, San Francisco, August 1989.  相似文献   
75.
Readers wishing to correspond with Mr. O’Connell may do so through the editorial office of the Journal.  相似文献   
76.
Differential participation after recruitment remains a black box in the social-movement and voluntary-association literatures. This paper identifies several dimensions of membership participation in a professional social-movement organization (SMO) with a national membership and analyzes the determinants of differential involvement in these forms. In general, members' ideological beliefs, social and organizational ties, perceptions about their SMO, and communication with SMO officials all predict participation across the various forms. Our findings extend previous work on differential participation in three ways. First, we statistically isolate cultural dimensions of postrecruitment participation and, in so doing, complement recent ethnographic research. Second, our findings suggest that the distinct dimensions of external and internal participation found by Knoke (1988) in a national sample of voluntary associations may not generalize to national SMOs studied individually. Third, our results indicate that models combining ideological and microstructural factors should explain the multiple forms of participation in SMOs lacking these distinct dimensions.  相似文献   
77.
Abstract Agroforestry, the practice of raising crops and trees together in ways that are mutually beneficial, provides farmers with an alternative to more conventional farming practices. In this paper, we apply Bourdieu's concepts of “field” and “habitus” in an attempt to better understand the practice of farming and the role that agroforestry may have in farming systems. Analysis is based on qualitative and quantitative interviews of farmers and other key informants in two regions, Fox‐Wyaconda Watershed in northeast Missouri and Scott County in southeast Missouri. Within the field of farming, farmers emphasized the importance of economic, family and rental relations. Important habitus considerations include different interpretations of what constitutes farming and what constitutes forestry. Based on Bourdieu's theoretical framework, we offer three alternative paths of social change that may lead to more widespread utilization of agroforestry.  相似文献   
78.
This paper reports on an evaluation of the Cornwall Young Carers project (jointly funded by social services and the Cornwall and Isles of Scilly Health Action Zone), conducted during the period 2000–2002. A diverse range of methodological approaches were adopted (comparative national statistics, local pilot study, monthly and quarterly data capturing instruments, and a service user focus group) in monitoring and evaluating the project's high level statements/outcomes. Four evaluative themes are discussed, namely: identification of young carers; assessment of young carers' needs; direct service provision; and partnership working. Recommendations and action steps are proposed with a view of informing future planning and service delivery, as well as developing an ethos of integrating evaluation into everyday practice for the Cornwall Young Carers Project. Overall, the project has made significant progress in meeting and exceeding its original targets. The fact that the project has been able to identify 202 new young carers over this period is a key milestone in demonstrating the critical need for the project's services. It is suggested that existing referrals are only the ‘tip of the iceberg’ for work with young carers in Cornwall.  相似文献   
79.
80.
In this paper, the history of atmospheric science is traced, from the earliest discussions from meteorologists, and the first meetings to describe this new research area. The development of atmospheric science proceeded in three phases with each phase being marked by the attempt to organize resources, and bring into the atmospheric science network, scientists from other fields. I argue here that this construction of a science provides evidence of the social nature of science as well as the importance of organizations to the creation of a science.  相似文献   
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