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261.
Health Risk Assessment of a Modern Municipal Waste Incinerator   总被引:2,自引:0,他引:2  
During the modernization of the municipal waste incinerator (MWI, maximum capacity of 180,000 tons per year) of Metropolitan Grenoble (405,000 inhabitants), in France, a risk assessment was conducted, based on four tracer pollutants: two volatile organic compounds (benzene and 1, 1, 1 trichloroethane) and two heavy metals (nickel and cadmium, measured in particles). A Gaussian plume dispersion model, applied to maximum emissions measured at the MWI stacks, was used to estimate the distribution of these pollutants in the atmosphere throughout the metropolitan area. A random sample telephone survey (570 subjects) gathered data on time-activity patterns, according to demographic characteristics of the population. Life-long exposure was assessed as a time-weighted average of ambient air concentrations. Inhalation alone was considered because, in the Grenoble urban setting, other routes of exposure are not likely. A Monte Carlo simulation was used to describe probability distributions of exposures and risks. The median of the life-long personal exposures distribution to MWI benzene was 3.2·10–5 g/m3 (20th and 80th percentiles = 1.5·10–5 and 6.5·10–5 g/m3), yielding a 2.6·10–10 carcinogenic risk (1.2·10–10–5.4·10–10). For nickel, the corresponding life-time exposure and cancer risk were 1.8·10–4 g/m3 (0.9.10–4 – 3.6·10–4 g/m3) and 8.6·10–8 (4.3·10–8–17.3·10–8); for cadmium they were respectively 8.3·10–6 g/m3 (4.0·10–6–17.6·10–6) and 1.5·10–8 (7.2·10–9–3.1·10–8). Inhalation exposure to cadmium emitted by the MWI represented less than 1% of the WHO Air Quality Guideline (5 ng/m3), while there was a margin of exposure of more than 109 between the NOAEL (150 ppm) and exposure estimates to trichloroethane. Neither dioxins nor mercury, a volatile metal, were measured. This could lessen the attributable life-long risks estimated. The minute (VOCs and cadmium) to moderate (nickel) exposure and risk estimates are in accord with other studies on modern MWIs meeting recent emission regulations, however.  相似文献   
262.
This paper describes and evaluates “As luck would have it,” an awareness program completed by retailers in Quebec Province. This program, which is presented as a two-hour awareness promotion workshop, aimed to inform retailers about excessive gambling. More specifically, it provided answers to the following questions: (1) What is chance and randomness? (2) Is there a link between misunderstanding the concept of chance and excessive gambling? (3) How does one recognise the symptoms of this disorder? (4) How should retailers intervene if they decide to do so? Results showed that retailers developed a better understanding of problem gambling, could recognise its main symptoms, felt more capable of coping with excessive gamblers, and of choosing the most appropriate moment to do so. In the follow-up phase, retailers who had attended the workshop reported that they approached a problem gambler significantly more often than the retailers who had not attended the workshop, and had discussed how to help problem gamblers significantly more often. The practical implications of these results are briefly discussed.  相似文献   
263.
This article describes the third phase of a research study undertaken within a Canadian provincial regional health authority to explore and analyze mental health services and other resources used by rural consumers after discharge from inpatient mental health programs. The focus of this article is the qualitative research findings obtained from mental health service providers and members of allied agencies. This article will discuss the literature on rural consumers' access and use of mental health programs and services; describe the context and method used to conduct the focus groups with rural service providers; characterize access and use problems from the service providers' perspectives; and suggest strategies to address these problems.  相似文献   
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Conventional approaches for inference about efficiency in parametric stochastic frontier (PSF) models are based on percentiles of the estimated distribution of the one-sided error term, conditional on the composite error. When used as prediction intervals, coverage is poor when the signal-to-noise ratio is low, but improves slowly as sample size increases. We show that prediction intervals estimated by bagging yield much better coverages than the conventional approach, even with low signal-to-noise ratios. We also present a bootstrap method that gives confidence interval estimates for (conditional) expectations of efficiency, and which have good coverage properties that improve with sample size. In addition, researchers who estimate PSF models typically reject models, samples, or both when residuals have skewness in the “wrong” direction, i.e., in a direction that would seem to indicate absence of inefficiency. We show that correctly specified models can generate samples with “wrongly” skewed residuals, even when the variance of the inefficiency process is nonzero. Both our bagging and bootstrap methods provide useful information about inefficiency and model parameters irrespective of whether residuals have skewness in the desired direction.  相似文献   
267.
Peleg (1978) presents a necessary and sufficient condition for the non-emptiness of the core, by considering quota games. The purpose of this paper is to present a similar result for the non-emptiness of another solution concept introduced by Rubinstein (1980) and called the stability set. Received: 25 January 1999/Accepted: 6 July 1999  相似文献   
268.
Empirical studies of ambiguity aversion often use measures that are not grounded in theory. This paper shows how a theoretically-founded measure of ambiguity aversion can be derived from Hansen and Sargent’s theory of multiplier preferences. Multiplier preferences are used in macroeconomics to capture model uncertainty. At the micro level, they have not been applied yet, because they do not permit ambiguity seeking, which is usually observed for a substantial proportion of subjects. We give a preference foundation for (extended) multiplier preferences accommodating both ambiguity aversion and ambiguity seeking and we propose a simple method to measure them using matching probabilities. We illustrate our method in two large representative samples (Dutch and American) and obtain the first micro estimates of multiplier preferences.  相似文献   
269.
This study, based on quantitative and qualitative surveys conducted from July 2004 to September 2005, examines the perceptions of Hanoi consumers and their reactions to the Avian Influenza epizootic (H5N1). Hanoi consumers clearly link the risk of human contamination by the virus to the preparation and ingestion of poultry. During the first crisis, consumers reacted quickly and intensely (74% of them had already stopped eating poultry in January 2004). Nevertheless, once the crisis abated, they quickly resumed their consumption of poultry. This behavior corresponds to the pattern described by empirical studies of other crises, such as BSE. What is more surprising is the speed with which the different steps of this common pattern succeeded one another. It may be explained by a rapid decrease in risk anxiety. A logit model shows that, soon after the beginning of the crisis, AI risk anxiety was tempered by confidence in the information and recommendations issued by the government concerning AI and, in the long term, by a high perceived self-efficiency to deal with AI. Indeed, not only has poultry consumption been affected in terms of the quantity consumed, but alternative ways of selecting and preparing poultry have also been adopted as anti-risk practices. Risk communication strategies should take this into account, and rely on a previous assessment of consumer practices adopted to deal with the risk.  相似文献   
270.
This article aims to investigate parental influence on high-risk behavior by young people. Although research on the topic of perception of risk demonstrates that it is socially constructed, the role of the family in this construction has rarely been studied. Using a French national survey of more than 1,200 young drivers between the ages of 18 and 25, and their parents, we attempt to understand the transmission of risk within families. Our econometric study shows that parents influence both the practices and representations of their children. When parental norms and values are transmitted, they are by no means accepted in a wholly passive way. Indeed, the parental model is in competition with other models that originate from both inside the family (brothers and sisters) and outside it (instructors). Furthermore, parental influence decreases over time as young people become more experienced drivers and construct their own identity with regard to risk.  相似文献   
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