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71.
The probability of illness caused by very low doses of pathogens cannot generally be tested due to the numbers of subjects that would be needed, though such assessments of illness dose response are needed to evaluate drinking water standards. A predictive Bayesian dose-response assessment method was proposed previously to assess the unconditional probability of illness from available information and avoid the inconsistencies of confidence-based approaches. However, the method uses knowledge of the conditional dose-response form, and this form is not well established for the illness endpoint. A conditional parametric dose-response function for gastroenteric illness is proposed here based on simple numerical models of self-organized host-pathogen systems and probabilistic arguments. In the models, illnesses terminate when the host evolves by processes of natural selection to a self-organized critical value of wellness. A generalized beta-Poisson illness dose-response form emerges for the population as a whole. Use of this form is demonstrated in a predictive Bayesian dose-response assessment for cryptosporidiosis. Results suggest that a maximum allowable dose of 5.0 x 10(-7) oocysts/exposure (e.g., 2.5 x 10(-7) oocysts/L water) would correspond with the original goals of the U.S. Environmental Protection Agency Surface Water Treatment Rule, considering only primary illnesses resulting from Poisson-distributed pathogen counts. This estimate should be revised to account for non-Poisson distributions of Cryptosporidium parvum in drinking water and total response, considering secondary illness propagation in the population.  相似文献   
72.
Summary. Possible health hazards from mobile phones arise from the use of the phones themselves and via the base stations that relay signals. Except for an increase in traffic accidents induced by the use of mobile phones in cars the evidence for a health hazard is at most indirect, but it cannot be entirely dismissed; the phones have not been widely used for sufficiently long for direct epidemiological studies to have high sensitivity for detecting any induced incidence of cancer, for example. The background and evidence are briefly reviewed and the steps taken in the UK to make information widely available described.  相似文献   
73.
The Alchian and Allen theorem predicts that it will be harder to find "good" apples in the State of Washington, a prime apple-growing region, than in, say, New York City, where the addition of shipping charges makes "bad" apples comparatively more expensive. We recast the theorem as a testable proposition by explicitly taking the supply side into account and identifying plausible scenarios in which a fixed cost either has no effect on the relative prices of high and low quality grades of the same good in distant markets or, indeed, causes more of the bad apples to be shipped out.  相似文献   
74.
1. Research shows that many emergency workers are affected physically and emotionally by critical incident stress. 2. Debriefings conducted by trained team members are an effective method to mitigate the impact of critical incident stress. A debriefing is a structured, time-limited group intervention. 3. Cooperation among community agencies is essential for the development and effective functioning of a critical incident stress debriefing team. 4. Several teams in Illinois have organized to form a Critical Incident Stress Debriefing Network. The Illinois network is part of an international organization composed of critical incident stress debriefing providers.  相似文献   
75.
Research on gambling has the double mandate of public service and the advancement of science. This paper is meant to carry forward that mandate. Latent in research on the causes of problem gambling is the policy insight that these causes represent different types of phenomena and are unequally mutable to practitioners' efforts to prevent and/or treat problem gambling. By making the issue of mutability manifest in research, findings from research would have more policy relevance and practical import. Data from a 1989 Iowa survey on lottery play and problem gambling are analyzed to illustrate this point. 1,226 respondents were contacted by phone and phone interviews were completed with 1,011 of these 1,226 eligible respondents. With multiple regression, we assessed the contributions of mutable and immutable variables to the explained variance in problem gambling. The results show mutable correlates explain enough variance in problem gambling to recommend their consideration in treatment/prevention. The results also suggest a social as well as a psychological etiology to problem gambling. Future research should, however, do a more complete comparison of social and psychological causes of problem gambling.This research was partially supported by the Iowa Department of Human Services and the National Institute of Mental Health (1 R01 MH50369-01A1). The authors wish to thank Willis Goudy, anonymous readers and the editor of this journal for helpful comments.  相似文献   
76.
This study examines the relationships among personal coping resources, social support, external coping resources, job stressors and job strains in a sample of 110 American Telephone and Telegraph employees undergoing a major organizational restructuring. The study expanded on a model suggested by Ashford (1988) by defining another category of coping resources that employees may draw upon to deal with the stressors and strains which occur during major organizational changes. External coping resources were defined as those which provided employees with a sense of 'vicarious control' in stressful situations. Results indicated that personal coping resources, social support and external coping resources had a direct effect upon job stressor and strain levels. No 'buffering' effect of these coplng resources was found. Hierarchical regression analyses indicated that external coping resources added to the prediction of job stressors and strains even when pertonal coping resources and social support were entered first into the prediction questions.  相似文献   
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79.
Childhood parental loss and adult depression   总被引:2,自引:0,他引:2  
Previous research demonstrates convincingly that childhood parental deaths and parental divorces have implications for adult well-being as defined by levels of depression, educational attainment, early age at marriage, and risk of divorce. What this research has failed to examine are the interconnections among these outcomes. Specifically, are the socioeconomic and marital outcomes of parental loss implicated in the observed higher levels of depression? This analysis takes a first step in answering this question. Using data from a sample of 1,755 married men and women, I estimated regression models which examine the extent to which adult socioeconomic status and current marital quality mediate and/or modify the loss-depression relationship. Parental divorce was strongly related to socioeconomic and marital outcomes. Furthermore, current marital quality contributed importantly to understanding the higher levels of depressed mood observed among persons from divorced homes. Parental death was much more weakly related to socioeconomic and marital outcomes, and these outcomes played little role in explaining its relationship to depression. Finally, all of these relationships were stronger among women than men. These findings support the utility of life-course approaches to understanding adult mental health.  相似文献   
80.
This paper describes specific transference and counter-transference issues that commonly emerge in therapeutic work with adolescents and parents who are in the midst of family transitions such as divorce and remarriage. Psychoanalytic understanding and definitions of transference and countertransference are applied to short-term family-centered cases in which the parent-adolescent relationship is at particular risk. Case vignettes are presented in order to illustrate how transference and countertransference may guide or interfere with clinical interventions that are especially indicated with adolescents whose family structure has changed. Such interventions as well as the use of consultation are briefly described.At the time this paper was prepared, Ms. Springer was Associate Director and a senior clinician at the Center for the Family in Transition in Corte Madera, California. Funds for the research and clinical work that provided the basis for this paper were supplied by grants from the San Francisco Foudation. An earlier version of this paper was presented at the 66th Annual Meeting of the American Orthopsychiatry Association, New York City, March 31–April 4, 1989.  相似文献   
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