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911.
The Texas Commission on Environmental Quality (TCEQ) has developed an inhalation unit risk factor (URF) for 1,3-butadiene based on leukemia mortality in an updated epidemiological study on styrene-butadiene rubber production workers conducted by researchers at the University of Alabama at Birmingham. Exposure estimates were updated and an exposure estimate validation study as well as dose-response modeling were conducted by these researchers. This information was not available to the U.S. Environmental Protection Agency when it prepared its health assessment of 1,3-butadiene in 2002. An extensive analysis conducted by TCEQ discusses dose-response modeling, estimating risk for the general population from occupational workers, estimating risk for potentially sensitive subpopulations, effect of occupational exposure estimation error, and use of mortality rates to predict incidence. The URF is 5.0 × 10−7 per μg/m3 or 1.1 × 10−6 per ppb and is based on a Cox regression dose-response model using restricted continuous data with age as a covariate, and a linear low-dose extrapolation default approach using the 95% lower confidence limit as the point of departure. Age-dependent adjustment factors were applied to account for possible increased susceptibility for early life exposure. The air concentration at 1 in 100,000 excess leukemia mortality, the no-significant-risk level, is 20 μg/m3 (9.1 ppb), which is slightly lower than the TCEQ chronic reference value of 33 μg/m3 (15 ppb) protective of ovarian atrophy. These values will be used to evaluate ambient air monitoring data so the general public is protected against adverse health effects from chronic exposure to 1,3-butadiene.  相似文献   
912.
913.
Motion picture performance: A review and research agenda   总被引:1,自引:0,他引:1  
This paper provides a comprehensive literature review of empirical studies of motion picture performance published from 1977 to 2006 inclusive in the following five disciplines of the social sciences: strategy, organization theory, marketing, cultural economics and sociology. It introduces a novel framework which organizes the various dimensions and explanatory factors of movie performance into five distinct categories and underscores their relationships. The paper, which uses this model as a roadmap for discussions of film success, serves two complementary purposes. First, it clarifies the current state of the literature, stresses core contributions and exposes limitations in existing research by emphasizing hitherto neglected independent explanatory factors, dependent dimensions and correlations between them. Second, it introduces five conceptual, methodological and empirical suggestions for further cinema performance research aimed at addressing these limitations and, accordingly, at providing better accounts of motion picture performance in view of the fast-changing conditions of cinema production, marketing and consumption.  相似文献   
914.
Relative income differences are likely to lead to envy within a reference group. Envy in turn influences social behavior and individual performance. While positional concerns are apparent in daily life, empirical evidence is rare in the economic literature. This paper investigates the impact of the relative income position on individuals’ performance or productivity. As ?performance“ is difficult to measure we turn to soccer players whose performance has been well documented. The broad sample covers eight seasons of the German premier soccer league (Bundesliga) between 1995 and 2004, and includes 1040 players, a salary proxy and several performance variables. The results show that player performance is strongly affected by relative income position. A disadvantage in the relative income position reduces productivity. The larger the income differences within a team, the stronger are the effects of positional concern. Team composition also significantly affects behaviour.  相似文献   
915.
When using data envelopment analysis (DEA) as a benchmarking technique for nursing homes, it is essential to include measures of the quality of care. We survey applications where quality has been incorporated into DEA models and consider the concerns that arise when the results show that quality measures have been effectively ignored. Three modeling techniques are identified that address these concerns. Each of these techniques requires some input from management as to the proper emphasis to be placed on the quality aspect of performance. We report the results of a case study in which we apply these techniques to a DEA model of nursing home performance. We examine in depth not only the resulting efficiency scores, but also the benchmark sets and the weights given to the input and output measures. We find that two of the techniques are effective in insuring that DEA results discriminate between high and low quality performance.  相似文献   
916.
Latane and Darley developed a five-stage model to understand why people do and do not help other people in emergency situations. We extend their five-stage model to explore why people do and do not take action against climate change. We identify the factors that make climate change difficult to notice and ambiguous as an emergency; we explore barriers to taking responsibility for action; and we discuss the issues of efficacy and costs versus benefits that make action unlikely. The resulting analysis is useful on two levels. For educators and policy makers, the model suggests the most efficacious approaches to galvanizing action among U.S. citizens. For social scientists, the model provides a valuable framework for integrating research from diverse areas of psychology and suggests fruitful avenues for future empirical research.  相似文献   
917.
The author responds to reviews of his book, Planting Hatred, Sowing Pain: The Psychology of the Israeli-Palestinian Conflict. Reviewers argue that you cannot understand the psychology of this conflict from an objective perspective, without taking issues such as historical context and social justice in consideration. The author argues that this detachment is necessary in order to find a solution, since we need to move beyond an orientation to the past that amounts to a culpability paradigm, and into an orientation to the future and a resolution paradigm. Only after you achieve peace and build mutual trust, could the parties be ready to do soul searching and take responsibility for their past actions.  相似文献   
918.
This paper investigates the link between the optimal level of nonfinancial firms' short-term leverage and macroeconomic and idiosyncratic sources of uncertainty. We develop a structural model of a firm's value maximization problem that predicts a negative relationship between uncertainty and optimal levels of borrowing. This proposition is tested using a panel of nonfinancial U.S. firms drawn from the COMPUSTAT quarterly database covering the period 1993–2003. The estimates confirm that as either form of uncertainty increases, firms decrease their levels of short-term leverage. This effect is stronger for macroeconomic uncertainty than for idiosyncratic uncertainty. ( JEL C23, D8, D92, G32)  相似文献   
919.
Growing diversity within the US population accentuates the need for the development and implementation of culturally competent services in the field of child welfare. Despite this, few studies exist that examine the effectiveness of culturally sensitive interventions (CSIs) with ethnic minority populations, who are considerably more at risk of developing psychosocial problems including substance and alcohol abuse, delinquency, low academic achievement, and poor self-esteem. With the demand for evidence-based practice it is imperative that we examine the effectiveness of CSIs designed to prevent and treat youth problems. The main goal of this review was to systematically analyze the methodology of recent CSI research with populations of ethnic minority youth in order to evaluate each intervention's ability to adhere to existing standards of evidence-based practice. The fifteen CSI studies examined in this review illustrate progress in their attempt to adhere to the methodological rigor required of evidence-based practice. This review encourages the field of child welfare to position itself analogously with and embrace the movement toward building cultural competence by further investigating the effectiveness of culturally-sensitive interventions with ethnic minority youth.  相似文献   
920.
Companies are now investing in the new technologies of the 1990s. This article deals with the central question of why and how companies work together on technological innovation. First the author looks at the reality of technological innovation, and review reasons why companies might want to work together in this area. They then uncover the different types of collaboration involved in technological innovation. These forms are innovation networks, and they identify several success factors for innovation networks.  相似文献   
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