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Providing information about the strength of different alcoholic beverages is a common component of alcohol abuse prevention programs. However, little is known about drinkers' knowledge of the strength of different alcoholic beverages. In the present study, 113 young adult drinkers responded to a questionnaire concerning the alcohol content of different types of malt beverages (beers, malt liquors), wines, fortified wines (port, sherry), and distilled spirits. The results indicated rates of correct responses well below 50 percent for each type of alcoholic beverage, with a substantial proportion of subjects either overestimating or underestimating alcohol content. Not a single subject reported correct alcohol content values for all four beverage types. There was a trend towards less accurate estimates of the alcohol content of strength were less accurate than those of men. The results are discussed in terms of prevention of alcohol abuse. 相似文献
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The joint persistence (JP) quantifies the environmental persistence of a parent compound and a selection of relevant transformation products. Here, the importance as well as the uncertainty of the JP in comparison to the persistence of the parent compound alone (primary persistence, PP) are investigated. To demonstrate the effect of transformation products on the environmental persistence of organic chemicals, three case studies of parent compounds (nonylphenol ethoxylates, perchloroethylene, atrazine) and transformation products are investigated in detail with a multimedia fate model. Comparison of the PP and JP values shows that transformation products can significantly increase the persistence. In addition to the point estimates of PP and JP, the associated uncertainties are investigated. For each of the case studies, the chemical-specific input parameters of all compounds are varied and the corresponding variance of the PP and JP is determined by Monte Carlo simulations. Interestingly, the higher number of input parameters required for the JP does not necessarily increase the uncertainty of the JP as compared to that of the PP alone. An exact mathematical expression specifying the contribution of each transformation product to the JP is given. When transformation products are grouped in different generations, it becomes discernible that the first generation increases the JP most; the later generations are of decreasing importance. Finally, the effect of incomplete knowledge of the transformation products and their properties on the JP results is discussed. For reliable JP estimates, knowledge of the first generation transformation products and their degradation rate constants is required. 相似文献
887.
Given only a random sample of observations, the usual estimator for the population mean is the sample mean. If additional information is provided it might be possible in some situations to obtain a better estimator. The situation considered here is when the variable whose mean is sought is composed of factors that are themselves observable. In the basic case, the variable can be expressed as the product of two, independent, more basic variables, but we also consider the case of more than two, the effect of correlation, and when there are observation costs. 相似文献
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Anthea Bill William Mitchell Martin Watts 《The Australian journal of social issues》2006,41(2):233-245
This paper employs the Labour Market Accounts framework to explore how employment growth and commuting patterns interacted to determine changes in the spatial distribution of unemployment in Statistical Local Areas within the NSW GMR over the period 1996–2001. Separate regression models (including control variables) for men and women provide estimates of the relative strength of the relationships between these labour market adjustment responses and the percentage local employment change. The results show that employment growth between 1996 and 2001 has elicited substantial changes in commuting behaviour. Men reveal greater in‐commuting and migration responsiveness to employment growth. Unemployment changes in local areas of the Greater Metropolitan Sydney region have been swamped by commuting responses, potentially posing problems for locally targeted employment strategies. 相似文献
889.
Martin G. kushler 《Evaluation and program planning》1983,6(2):115-119
In response to the complex and expensive Bonneville Power Administration (BPA) evaluation plan, this article attempts to identify some pragmatic issues and alternative approaches to conservation program evaluation. In particular, the need for simpler, lower-cost evaluation options and the importance of process evaluation to program management are emphasised. This is followed by the delineation of several key principles to be observed in conducting a more modest, but still methodologically sound and managerially useful, evaluation of energy conservation programs. 相似文献
890.
In this interview Graham Martin reflects on his long career in child and adolescent mental health. He shares his formative experiences with some of the pioneers in the field of attachment theory and the many varied ways that this information has influenced his work in the provision of care to children in hospital, health promotion, understanding the distress of suicidal youth, and his ongoing therapeutic work with families. 相似文献