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931.
J. S. Evans L. R. Rhomberg P. L. Williams A. M. Wilson & S. J. S. Baird 《Risk analysis》2001,21(4):697-718
Ethylene oxide is a gas produced in large quantities in the United States that is used primarily as a chemical intermediate in the production of ethylene glycol, propylene glycol, non-ionic surfactants, ethanolamines, glycol ethers, and other chemicals. It has been well established that ethylene oxide can induce cancer, genetic, reproductive and developmental, and acute health effects in animals. The U.S. Environmental Protection Agency is currently developing both a cancer potency factor and a reference concentration (RfC) for ethylene oxide. This study used the rich database on the reproductive and developmental effects of ethylene oxide to develop a probabilistic characterization of possible regulatory thresholds for ethylene oxide. This analysis was based on the standard regulatory approach for noncancer risk assessment, but involved several innovative elements, such as: (1) the use of advanced statistical methods to account for correlations in developmental outcomes among littermates and allow for simultaneous control of covariates (such as litter size); (2) the application of a probabilistic approach for characterizing the uncertainty in extrapolating the animal results to humans; and (3) the use of a quantitative approach to account for the variation in heterogeneity among the human population. This article presents several classes of results, including: (1) probabilistic characterizations of ED10s for two quantal reproductive outcomes-resorption and fetal death, (2) probabilistic characterizations of one developmental outcome-the dose expected to yield a 5% reduction in fetal (or pup) weight, (3) estimates of the RfCs that would result from using these values in the standard regulatory approach for noncancer risk assessment, and (4) a probabilistic characterization of the level of ethylene oxide exposure that would be expected to yield a 1/1,000 increase in the risk of reproductive or developmental outcomes in exposed human populations. 相似文献
932.
Efficiency of environmental surveillance of poliovirus circulation was studied using simulation models. First, three transmission models were defined for describing different scenarios of poliovirus infections in a large unstructured population. Second, environmental factors, such as the total volume of the sewage network and losses of viruses, were modeled for computing the virus output at the sewage sampling site. Third, the effect of sampling and laboratory procedures was accounted for in the probability of detection, given the amount of polioviruses in a specimen. The simulation model can be used for theoretical assessments of the likely efficiency of environmental surveillance, compared with acute flaccid paralysis (AFP) surveillance. Under reasonable assumptions in a vaccinated population, the AFP surveillance can be outperformed if the poliovirus outbreak is not large. However, this depends on the assumed case-to-infection ratio and on the sampling frequency of the sewage water specimens. Increasing the latter will lead to a higher detection probability, which will further enhance the method based on environmental surveillance. 相似文献
933.
This article describes how the effectiveness of risk communication is determined by the interaction between emotional and informative elements. An experiment is described that examined the role of negative emotion in communication about CO2 risks. This experiment was based on the elaboration likelihood model and the related heuristic systematic model of attitude formation. The results indicated that inducing fear of CO2 risks leads to systematic processing of information about energy conservation as a risk-reducing strategy. In turn, this results in more favorable attitudes toward energy conservation if strong arguments are provided. Individual differences in concern seem to have similar effects. 相似文献
934.
Variable precision rough set theory and data discretisation: an application to corporate failure prediction 总被引:1,自引:0,他引:1
Since the seminal work of Pawlak (International Journal of Information and Computer Science, 11 (1982) 341–356) rough set theory (RST) has evolved into a rule-based decision-making technique. To date, however, relatively little empirical research has been conducted on the efficacy of the rough set approach in the context of business and finance applications. This paper extends previous research by employing a development of RST, namely the variable precision rough sets (VPRS) model, in an experiment to predict between failed and non-failed UK companies. It also utilizes the FUSINTER discretisation method which neglates the influence of an ‘expert’ opinion. The results of the VPRS analysis are compared to those generated by the classical logit and multivariate discriminant analysis, together with more closely related non-parametric decision tree methods. It is concluded that VPRS is a promising addition to existing methods in that it is a practical tool, which generates explicit probabilistic rules from a given information system, with the rules offering the decision maker informative insights into classification problems. 相似文献
935.
A national membership survey of Hemlock Society USA was conducted by Fox and Kamakahi (1995). Respondents (N=6398) were asked a variety of questions, but in this paper we perform a longitudinal analysis of the characteristics of Hemlock Society USA members. Hemlock Society USA members are divided into three 5-year cohorts: Early Joiners (11 or more years of membership), Middle Joiners (6 to 10 years membership), and Late Joiners (5 or fewer years of membership). Differences between cohorts are examined and extrapolations made regarding Hemlock Society USA and the Right-to-Die Movement. A series of one-way ANOVAs were used with Scheme post-hoc comparisons as heuristic tools for assessing between-cohort differences. Late Joiners are different from earlier members, but are more like other Hemlock Society USA members than the adult U.S. population at large. Hemlock Society USA members are essentially societal "elites" (based on socio-demographic variables) who work in social environments that are decidedly split on the issue of voluntary suicide and euthanasia. 相似文献
936.
937.
The ISO 9000 series of quality management systems standards and the more recent ISO 14000 environmental management systems standards have generated much controversy among practitioners. Although ISO 9000 has become a de facto requirement for many firms, its effects are poorly understood, and similarly the value and domain of applicability of ISO 14000 have been questioned. This paper reports on an exploratory study into the global spread of ISO 14000. We interviewed practitioners worldwide to identify factors that they believe explain differences between national ISO 14000 certification counts. We then collected quantititive data for these factors and, using regression analysis, we found that exports, environmental attitudes (combined with economic development), and ISO 9000 certification count were significant. The fact that ISO 9000 appears as an important factor explaining diffusion of ISO 14000 certifications suggests that the drivers behind the two have significant overlap. This indicates that, although ISO 14000 is an environmental standard, many of the factors driving national certification patterns are not at all environmental in nature, and that ISO 14000 therefore needs to be studied from a broader perspective than from a purely environmental point of view. 相似文献
938.
Beyond products: new strategic imperatives for developing competencies in dynamic environments 总被引:1,自引:0,他引:1
Sally W. Fowler Adelaide Wilcox King Sarah J. Marsh Bart Victor 《Journal of Engineering and Technology Management》2000,17(3-4)
Strategy research has often taken a product-centered perspective. When firms compete in environments characterized by accelerating product life cycles, mass customization, and technological discontinuities, a product-centered perspective on strategy may help explain a firm’s current competitive advantage. However, this perspective adds little guidance in making strategies that create competitive advantage in the future. In this paper, we present a perspective in which dynamic environments require firms to focus on (1) building market-driven, technological, and integration competencies, not a stream of product improvements, and (2) decoupling these competencies from current products in order to create and exploit new opportunities. We discuss the perspective of products as a temporary integration of market and technology trajectories. Research propositions are presented and future implications are discussed. 相似文献
939.
Jürgen Fabian 《Organisationsberatung, Supervision, Coaching》2000,7(3):252-260
Development of head masters by group coaching In discussion on school development, a central role is attributed to the head masters. Beside these expectations concerning an innovative activity, the head masters act for the maintaining of the everyday school functioning in the context of very different and partly conflicting expectations. Coaching may give a support by refering immediately to the everyday work of the head masters. This article focusses on group coaching, outlines the special procedure in group coaching and compares it with other forms of personal development of head masters. 相似文献
940.
Violence against psychiatric staff seems to be on the increase. Such abuse can lead to mental health consequences for the staff and a reluctance to be closely involved with patients. Few Swedish investigations have examined violence against mental nurses and psychiatrists, or undertaken comparative studies between them. In this study we examined the extent, nature and determinants (i.e. risk factors) of violence against psychiatric nurses (n = 731) and psychiatrists (n = 320) working in the eight health care districts of Stockholm. These caregivers were assessed cross-sectionally by means of a questionnaire covering various areas (e.g. violence and work environment). The majority of the participants (85%) reported having been exposed to violence during their careers, with 57% being victimized in the past 12 months. Physical violence was common, and factors such as negative attitudes to work and diminished sense of autonomy were associated with an increased vulnerability to violence. Nurses and psychiatrists did not differ in violence variables. In spite of the weaknesses of the design (cross-sectional self-selecting sample), this study corroborates previous findings and identifies personal factors associated with violence that have received little attention in the literature (e.g. lack of respect for the organization of care). 相似文献