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91.
The concept of exposure is central to chemical risk assessment and plays an important role in communicating to the public about the potential health risks of chemicals. Research on chemical risk perception has found some indication that the model lay people use to judge chemical exposure differs from that of toxicologists, thereby leading to different conclusions about chemical safety. This paper presents the results of a series of studies directed toward developing a model for understanding how lay people interpret the concept of chemical exposure. The results indicate that people's beliefs about chemical exposure (and its risks) are based on two broad categories of inferences. One category of inferences relates to the nature in which contact with a chemical has taken place, including the amount of a chemical involved and its potential health consequences. A second category of inferences about chemical exposure relates to the pragmatics of language interpretation, leading to beliefs about the motives and purposes behind chemical risk communication. Risk communicators are encouraged to consider how alternative models of exposure and language interpretation can lead to conflicting conclusions on the part of the public about chemical safety.  相似文献   
92.
We examine the relative importance of tax rates and macroeconomic fluctuations in explaining the share of national adjusted gross income (AGI) reported by the top 0.5% of all taxpayers. Results indicate that cutting the top income or capital gains tax rate would increase the top AGI share but not by enough to increase revenues. The preponderance of evidence suggests that the top AGI share is affected more by the capital gains tax rate than by the income tax rate but that real gross domestic product fluctuations have even larger effects.  相似文献   
93.
Staphylococcus aureus is a gram-positive, enterotoxin-producing coccus. It is a hardy organism and known to survive over a wide range of water activities, pH values, and temperatures. The objective of this study was to model the survival or gradual inactivation of S. aureus ATCC 13565 in intermediate moisture foods (IMFs). Various initial concentrations (approximately 10(1), 10(2), 10(3), and 10(4) CFU/g) were used to inoculate three different IMFs (beefsteak, bread, and chicken pockets). Viable counts were determined up to 60 days using tryptic soy agar. Inoculum size did not influence the survival or gradual inactivation of S. aureus in these foods. The rate of change (increase or decrease) in log CFU/day was calculated for every consecutive pair of data points and by linear regression for each inactivation curve. Both consecutive pair and linear regression rates of change were fit to logistic distributions (with parameters alpha and beta) for each food. Based on the distribution parameters, survival or gradual inactivation of S. aureus was predicted by computer simulation. The simulations indicated an overall decline in S. aureus population over time, although a small fraction of samples in the consecutive pair simulation showed a slight population increase even after 60 days, consistent with the observed data. Simulation results were compared to predictions from other computer models. The models of Stewart et al., were fail-safe, predicting the possibility of significant growth only after > 3,000 days. The USDA pathogen modeling program predictions were found to be fail-dangerous, predicting declines at least four times faster than observed.  相似文献   
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St. Wolfgang College recently decided to change its health care plan. The administration took this action after just minimum consultation with the faculty. Consequently, the faculty is disheartened, seeing the action as a reflection of the college's top down decision making process and command culture. Faculty are in a quadary as to what they can do. Further, the administration of the college has largely rebuffed the faculty's efforts to increase its involvement in governance, rejecting a faculty reform effort. The college's president has a background primarily in administration at the secondary school level. Since assuming leadership he has focused on improving physical plant. He avows a mission of enhancing the college's academic reputation and has taken actions that he and the administration believe will achieve this goal, such as dismantling two year degree programs that primarily serve disadvantaged and minority students and providing extra funding to flagship programs.  相似文献   
97.
Measuring the impact of potentially controllable factors on the willingness of youth to undertake health risks is important to informed public health policy decisions. Typically the only data linking these factors with risk-taking behavior are retrospective. This study demonstrates, by means of a recent example, that there can be serious pitfalls in using even longitudinal retrospective data to draw conclusions about causal relations between potentially controllable factors and risk-taking behavior.  相似文献   
98.
The Beacon Art Center and Institute, located in an area of Florida experiencing rapid population growth, has enjoyed increases in membership,revenue and services. The Board of the Corporation and the Director must develop a long range strategic plan for the future of the organization. Ability to function is currently restricted by limited space, limited size of staff, and limited endowment. The center also faces potentially troublesome governance issues. The long run future of the art center must be addressed by the Board and the Director of the organization. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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HIGH SCHOOLS AND CRIME: A REPLICATION   总被引:1,自引:0,他引:1  
Using Cleveland data, we replicate Roncek and LoBosco's study of the effect of proximity to San Diego's high schools on crime in their surroundings. We also examine a major alternative hypothesis whether having other non-residential land uses in the schools' surroundings accounts for crime in these areas. Our findings closely parallel theirs. Proximity to public high schools only increases crime on city blocks which are immediately adjacent to the schools. Second, the size of a school's enrollment is not important for explaining crime in its surroundings. The analysis of non-residential effects supports Roncek and LoBosco's claim that crime effects are due solely to the presence of public high schools, although other land uses affect crime near private high schools. While there are differences in the exact magnitudes of the effects, the substance of their findings for San Diego generalizes well to a very different city. More generally, we argue that Wirth's early arguments about the effect of urbanism on impeding social control can be extended to the residential areas within the city.  相似文献   
100.
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