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101.
A tank car derailment in northern California in 1991 spilled metam sodium into the Sacramento River, and released its breakdown product, methyl isothiocyanate (MITC), into the air. This paper describes the risk evaluation process used. Over 240 individuals reported symptoms such as eye and throat irritation, dizziness, and shortness of breath. Reference exposure levels (RELs) for 1 hr were developed for MITC and compared to exposure concentrations. Ocular irritation in cats was the most sensitive endpoint reported. The no observed adverse effect level (NOAEL), divided by an uncertainty factor (UF) of 100, produced an REL of 0.5 ppb of MITC in air to prevent discomfort. An REL to prevent disability was estimated to be 40 ppb. An REL to prevent life-threatening injury was estimated to be 150 ppb. Measured MITC levels ranged from 0.2-37 ppb and estimated peak levels ranged from 140-1600 ppb. The usefulness of RELs for emergency planning is discussed.  相似文献   
102.
A class of decisions, asset mix decisions made by pension fund managers, which exhibit characteristics of both programmed and strategic choices is examined in this paper. The decisions are classified using the scheme developed by Mintzberg et al., (1976) to highlight the circumstances under which strategic decisions may be programmed. The types of strategic decisions which lend themselves to programming are considered. The advantages and disadvantages of programming strategic decisions are also discussed.  相似文献   
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Several themes in Wirth's “Urbanism as a Way of Life” generate the prediction that alcohol use (versus nonuse) will be more widespread among residents of urban areas. Multiple regression analysis of data from two recent national polls (1966, 1968) reveals support for this prediction. With eight other key sociological variables simultaneously controlled, the greater the urbanism of a community (measured in terms of community size), the greater the proportion of alcohol users it contains. To make certain that this association is due to urban conditions (as opposed to merely the absence of rural forces which encourage abstinence), the effects of rural forces are reduced by omitting the most rural categories of the community size measure of urbanism, and the data are reexamined. The association still persists, basically because of the larger proportion of middle to upper status, white, and Protestant alcohol users in the more urban areas.  相似文献   
105.
Abstract The eruption of the volcano on Tristan da Cunha in 1961 and the subsequent arrival of the island population in the United Kingdom provided a unique opportunity for studying the health of this formerly isolated community. During their stay, while the facilities and services of modern medicine were made available to them, investigations of many facets of their general biology were made under the auspices of the Medical Research Council, co-ordinated by Dr. H. E. Lewis. Analysis of their demographic history was essential to understand many features of their disease pattern, and the results of this analysis are presented here. They are of interest in that they not only show some consistent trends in the common variables of demography, but also demonstrate biological principles, some perhaps for the first time in man, which may be fundamental in the process of colonization as a biological phenomenon, e.g. the initial difficulty of establishment of a population in a new area, the curious demographic structure that may emerge in its earliest years, the bottleneck effect of population-size reduction, the founder principle.  相似文献   
106.
Anecdotal reports have suggested that the use and abuse of methamphetamine is increasing in the United States. To date, however, few scholarly works have explored the prevalence and correlates of methamphetamine use in the United States. To address this limitation, a secondary analysis was undertaken with data collected through the Arrestee Drug Abuse Monitoring (ADAM) Program. An examination of methamphetamine-positive rates among ADAM arrestees interviewed between 1991 and 2001 identified that its use is concentrated within the Western part of the United States. Supplementary analyses of Sacramento arrestees indicated that 71% were diagnosed as needing some form of alcohol or other drug treatment. Compared to those arrestees who were detected methamphetamine-negative, methamphetamine-positive arrestees in Sacramento were three times as likely to be white and to have been diagnosed in need of drug treatment. Implications for drug control policy are discussed.  相似文献   
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108.
Risk acceptance criteria in the form of limit lines are investigated in the context of prospect theory. This theory departs from utility theory in several respects, an important one being the use of weights other than probabilities in the evaluation of the expected impact of uncertain outcomes. Hypothetical functions reflecting certain attitudes toward consequences and rare events are developed and combined to produce several limit lines.  相似文献   
109.
A method of therapy for families with an acting out adolescent or young adult is presented, as is a rationale for the method. The aim of the approach is to alter the underlying problem of immaturity that is hypothesized to exist in these families. Emphasis is placed on working with the parents in a systematic way over an extended period of time. As progress is made by the parents, an emotional crisis is created in the adolescent that can then be used by him as the basis for extensive change. The therapy of the parents proceeds in phases: 1) preparation for a long-term effort; 2) rethinking and objectively evaluating the nature of the relationship with the adolescent in specific areas; 3) translation of the newly gained perspective into action positions vis-à-vis the adolescent; and 4) non-child-focused therapy.  相似文献   
110.
An increasing body of evidence now suggests the involvement of mitochondrial abnormalities in the etiology of neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer disease. In this Perspective, we describe a recent study that shows that treatment of human patients with the antioxidant coenzyme Q(10'), which functions in concert with certain mitochondrial enzymes, reduced the worsening of symptoms associated with PD. These findings are consistent with the hypothesis that mitochondrial dysfunction plays a role in the pathogenesis of PD and that treatments that target mitochondrial biochemistry might ameliorate the functional decline observed in patients suffering from PD.  相似文献   
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