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The concept of exposure is central to chemical risk assessment and plays an important role in communicating to the public about the potential health risks of chemicals. Research on chemical risk perception has found some indication that the model lay people use to judge chemical exposure differs from that of toxicologists, thereby leading to different conclusions about chemical safety. This paper presents the results of a series of studies directed toward developing a model for understanding how lay people interpret the concept of chemical exposure. The results indicate that people's beliefs about chemical exposure (and its risks) are based on two broad categories of inferences. One category of inferences relates to the nature in which contact with a chemical has taken place, including the amount of a chemical involved and its potential health consequences. A second category of inferences about chemical exposure relates to the pragmatics of language interpretation, leading to beliefs about the motives and purposes behind chemical risk communication. Risk communicators are encouraged to consider how alternative models of exposure and language interpretation can lead to conflicting conclusions on the part of the public about chemical safety. 相似文献
987.
G Hirsch 《Physician executive》1999,25(2):30-35
Burnout is a state of physical, emotional, and mental exhaustion caused by long-term involvement in situations that are emotionally demanding. It is not stress, per se, that causes burnout, as many thrive in stressful, demanding careers. Rather, burnout results when stress continuously outweighs the sense of effectiveness, accomplishment, and reward. And, this fate is sealed when one feels helpless to effect significant change in the conditions that fuel the stress. Establishing an organizational environment that reduces the risk of physician burnout requires a new commitment of resources, one that can be challenging to justify to decision-makers with a strictly short-term, bottom line orientation. The key issues to consider in shaping a physician career management program include: (1) entry of new physician employees into the organization; (2) productivity measures; (3) responsiveness to safety concerns; (4) administrative and policy issues; and (5) variety and growth opportunities. 相似文献
988.
Planning authorities in Scotland are obliged to consult the public before finalising policies and proposals to be included in their development plans. Community councils are intended to operate as ‘the voice of a neighbourhood’ and this paper analyses an attempt by a regional planning authority to use community councils as a vehicle for consulting the public in the preparation of a structure plan for a rural area. The paper concludes that the attempt was unsuccessful because the community councils were not clear about the role they were expected to play; nor were they adequately prepared for their role. The authors believe, however, that the involvement of community councils has potential for promoting greater public participation in the preparation of development plans. 相似文献
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Incomplete covariate data is a common occurrence in many studies in which the outcome is survival time. With generalized linear models, when the missing covariates are categorical, a useful technique for obtaining parameter estimates is the EM by the method of weights proposed in Ibrahim (1990). In this article, we extend the EM by the method of weights to survival outcomes whose distributions may not fall in the class of generalized linear models. This method requires the estimation of the parameters of the distribution of the covariates. We present a clinical trials example with five covariates, four of which have some missing values. 相似文献