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41.
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   
42.
This paper examines the determinants of base pay and total incentive compensation packages of CEOs of biopharmaceutical firms that have recently gone public, and whether human capital and agency factors affect the market’s response to the initial public offering. We find that in terms of net proceeds, the IPO market appears to reward the firms that have founder-CEOs and CEOs with higher incentive compensation. CEOs with prior venture capital experience are associated with receiving higher incentive compensation, while CEOs with a greater ownership interest in the firm receive lower incentive compensation but higher salaries. CEOs of firms with a greater percentage of insiders are associated with lower salaries. The results should add to our understanding related to human capital and agency theories, as well as help firms and investors better understand and structure CEO compensation.  相似文献   
43.
Recently there has been a great deal of interest in studying monetary policy under model uncertainty. We point out that different assumptions about the uncertainty may result in drastically different “robust” policy recommendations. Therefore, we develop new methods to analyze uncertainty about the parameters of a model, the lag specification, the serial correlation of shocks, and the effects of real‐time data in one coherent structure. We consider both parametric and nonparametric specifications of this structure and use them to estimate the uncertainty in a small model of the U.S. economy. We then use our estimates to compute robust Bayesian and minimax monetary policy rules, which are designed to perform well in the face of uncertainty. Our results suggest that the aggressiveness recently found in robust policy rules is likely to be caused by overemphasizing uncertainty about economic dynamics at low frequencies. (JEL: E52, C32, D81)  相似文献   
44.
This paper relates a review of the English language literature on quality costing and traces its historical development; it provides authoritative reading on the subject. The review also has a focus on collection and use of quality-costing methods, quantitative cost data and the role and views of accountants in the task of quality-cost collection and reporting. Amongst the main findings is the preoccupation with the prevention – appraisal – failure categorization of quality costs and lack of guidance on definitions. The considerable impact of the American quality profession on the development of quality costing is pointed out along with the increasingly positive stance of accountants.  相似文献   
45.
This study uses a modified health belief model (HBM) within a socio-economic framework to evaluate the influence of awareness and knowledge on actions to reduce aflatoxin (AF) contamination in groundnuts (peanuts). Data were collected in 2002 through a self-administered questionnaire from a sample of 367 individuals. Socio-economic factors affecting perceptions, awareness, knowledge, and action were examined using structural equation modeling. The perceived benefits of good quality groundnuts and/or groundnut products were the most important determinants of awareness and knowledge of AF among agricultural and health professionals in Ghana. Awareness, in turn, had a significant causal effect on the professionals’ decisions to take actions to increase the level of awareness of AF in the society. Demographic factors, such as gender and level of education significantly influenced knowledge of AF and the perception of the benefits of good quality groundnut. Type of profession had a significant influence on awareness and perceived seriousness of the AF problem. Education was a significant determinant of awareness of AF in groundnuts. The study generates important information for policy decision making when considering resource allocation to reduce food contamination in developing economies.  相似文献   
46.
Food insufficiency is a significant problem in the United States, and poor African American women with children are at especially high risk. An inadequate household food supply can potentially affect the well-being of household members, but it is difficult to distinguish the effects of food insufficiency from risk factors for poor health that are also common among the food insufficient, such as poverty. We examined food insufficiency and physical and mental health among African American and white women (n = 676) who were welfare recipients in 1997. Controlling for common risk factors, women who reported food insufficiency in both 1997 and 1998 were more likely to report fair or poor health at the later date. Food insufficiency in 1998 was significantly associated with meeting the diagnostic screening criteria for recent major depression. Food insufficiency at both times and in 1998 only was related to women's sense of mastery. These findings add to growing evidence that household food insufficiency is associated with poor physical and mental health.  相似文献   
47.
Where strength training has been used in conjunction with functional-task training in older people, not only have there been improvements in leg strength but also improved function has been measured (e.g., Skelton & McLaughlin, 1996). Many studies use participants from care homes rather than community dwellers. We investigated changes in leg power, balance, and functional mobility in community-dwelling sedentary men and women over 70 years of age (n = 6 for training group [TR]; n = 10 for control group [CN]). Progressive training took place over 24 weeks using seated and nonseated exercise. For TR, leg power increased 40%, from 108 +/- 40 to 141 +/- 53 W (p < .01); dynamic balance increased 48%, from 22.3 +/- 7.9 to 33.1 +/- 6.1 cm (p < .01; functional reach); and functional mobility increased 12%, from 7.46 +/- 1.32 to 6.54 +/- 1.41 s (p < .05; timed walk). CN showed no significant change. In conclusion, a community-based exercise program led to large improvements in leg-extensor power, dynamic balance, and functional mobility.  相似文献   
48.
Effective targeted and community HIV/STD prevention programs   总被引:1,自引:0,他引:1  
Community interventions and interventions targeting specific groups at risk of STDs/HIV have demonstrated significant impacts on sexual behavior, particularly condom use and safer sex. The scientific evidence suggests the factors that make these interventions particularly effective include the establishment of community, including business and CBO partnerships; maintainance of the intervention post-research funding; and buy-in by the community or target group. The modification of risky normative beliefs through the use of opinion leaders and role models, and through intervention delivery by peer educators, is an important facet of such interventions. Interventions delivered by health professionals, absent a community base, appear to be unsuccessful. Where cultures or subcultures are targeted, the close involvement of such groups in the design and delivery of messages is critical to their success. Diffusion of interventions through existing social networks further extends the intervention into the community and acts to reinforce and maintain changes in peer norms toward safer sexual behavior. The available data confirm that community or medical infrastructure-based interventions are effective in changing sexual behavior and can reach a wider range of the population than face-to-face programs if they incorporate peer educators as role models in modifying norms, and if diffusion of the intervention is integral to the design.  相似文献   
49.
Work-related musculoskeletal injuries represent a major source of work disability. While many employers recognize the importance of workplace disability management approaches and are assuming greater responsibility for preventing and minimizing work-related disability, questions about the effectiveness of these interventions exist. The purposes of this article are to: 1) describe the essential components of workplace disability management programs related to musculoskeletal injuries; 2) review the literature on disability management practices based on research evidence by focussing on workplace-based interventions and the role of the workplace; and 3) provide recommendations for disability management in the prevention and reduction of disability, and the rehabilitation of injured workers with musculoskeletal work injuries. The literature suggests that employer participation, a supportive work climate and cooperation between labour and management are crucial factors in facilitating return to work. Given the complexity of the disability management process and the numbers of individuals involved, it is essential that all workplace parties work together to achieve the goal of safe and early return to work.  相似文献   
50.
In planning and implementing programs to treat substance abuse, it is important to understand which factors influence post-treatment abstinence.This article identifies and analyzes several variables important in predicting the likelihood of abstinence among substance abuse clients. The data used in this study was collected from 1,350 clients treated for alcohol or drug abuse in residential, halfway house, or outpatient facilities in Tennessee. We analyzed 22 variables as possible treatment outcome predictors by using two statistical procedures: stepwise logistic regression analysis and Quick, Unbiased, Efficient, Statistical Tree (QUEST) analysis, a tree-structured classification algorithm analysis. We found one pretreatment, five in-treatment, and three post-treatment variables to be significant predictors of treatment outcome: previous treatment history, perceived helpfulness of the treatment, simultaneous treatment for mental health, number of days in treatment,completion of treatment, special skills training during treatment, obtaining healthcare services for major physical health problem after treatment, living with someone using alcohol or drugs post treatment, and arrest record since treatment.  相似文献   
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