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21.
Recent studies demonstrating a concentration dependence of elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suggest that previous estimates of exposure for occupationally exposed cohorts may have underestimated actual exposure, resulting in a potential overestimate of the carcinogenic potency of TCDD in humans based on the mortality data for these cohorts. Using a database on U.S. chemical manufacturing workers potentially exposed to TCDD compiled by the National Institute for Occupational Safety and Health (NIOSH), we evaluated the impact of using a concentration- and age-dependent elimination model (CADM) (Aylward et al., 2005) on estimates of serum lipid area under the curve (AUC) for the NIOSH cohort. These data were used previously by Steenland et al. (2001) in combination with a first-order elimination model with an 8.7-year half-life to estimate cumulative serum lipid concentration (equivalent to AUC) for these workers for use in cancer dose-response assessment. Serum lipid TCDD measurements taken in 1988 for a subset of the cohort were combined with the NIOSH job exposure matrix and work histories to estimate dose rates per unit of exposure score. We evaluated the effect of choices in regression model (regression on untransformed vs. ln-transformed data and inclusion of a nonzero regression intercept) as well as the impact of choices of elimination models and parameters on estimated AUCs for the cohort. Central estimates for dose rate parameters derived from the serum-sampled subcohort were applied with the elimination models to time-specific exposure scores for the entire cohort to generate AUC estimates for all cohort members. Use of the CADM resulted in improved model fits to the serum sampling data compared to the first-order models. Dose rates varied by a factor of 50 among different combinations of elimination model, parameter sets, and regression models. Use of a CADM results in increases of up to five-fold in AUC estimates for the more highly exposed members of the cohort compared to estimates obtained using the first-order model with 8.7-year half-life. This degree of variation in the AUC estimates for this cohort would affect substantially the cancer potency estimates derived from the mortality data from this cohort. Such variability and uncertainty in the reconstructed serum lipid AUC estimates for this cohort, depending on elimination model, parameter set, and regression model, have not been described previously and are critical components in evaluating the dose-response data from the occupationally exposed populations.  相似文献   
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Young adults entering the job market are finding that, despite strong corporate profits, economic growth is not trickling down to worker earnings, and federal policies are moving from the notion of entitlement to one of blame (Uchitelle, 1996, Sec. 4, p. 1). Adolescence is becoming increasingly confusing, since for many Americans economic opportunity is more fantasy than reality. This article highlights the declining opportunity for young adults and points out the limitations of existing adult developmental theory, both of which call for altered treatment conceptualizations that include the clinician operating as an anthropologist and utilizing the concepts of relationship-differentiation and response/ability from Stone Center writings.  相似文献   
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Little documentation exists regarding the functioning of formalized adolescent groups as drug abuse prevention agents. Two studies are described that were conducted at high schools whose students are at high risk for drug abuse. Twenty-one schools were randomly assigned to one of three conditions: (a) standard care, (b) classroom drug abuse education only, or (c) classroom plus school-as-community. Results of the first study indicated that the school-as-community component--which involved weekly meetings and periodic events at seven schools--was implemented as planned, drug abused focused, and perceived as productive in discouraging drug abuse. In the second study, staff in the classroom plus school-as-community condition self-reported involvement in the greatest number of community activities across the school year, compared with staff from the other two conditions. These two studies support the feasibility of formalized groups of high-risk youth to promote drug-free events.  相似文献   
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European food retailers have increased their scale and scope while concentrating sales into large stores. Strategic implications include the need for scale to compete and organisational relationships to move from supply push to demand pull retailing. Consequences are different for private label and for branded manufacturers, who must respond to the demands of retail supply chains whilst retaining control of product development. Further concentration in both sectors is likely. Consumers are more mobile, but more captive to the retailer in store. Public policy makers are challenged to find new measures of retail power and both allow for innovation and ensure equitable shopping opportunities.  相似文献   
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This study focuses on levels of concern for hurricanes among individuals living along the Gulf Coast during the quiescent two‐year period following the exceptionally destructive 2005 hurricane season. A small study of risk perception and optimistic bias was conducted immediately following Hurricanes Katrina and Rita. Two years later, a follow‐up was done in which respondents were recontacted. This provided an opportunity to examine changes, and potential causal ordering, in risk perception and optimistic bias. The analysis uses 201 panel respondents who were matched across the two mail surveys. Measures included hurricane risk perception, optimistic bias for hurricane evacuation, past hurricane experience, and a small set of demographic variables (age, sex, income, and education). Paired t‐tests were used to compare scores across time. Hurricane risk perception declined and optimistic bias increased. Cross‐lagged correlations were used to test the potential causal ordering between risk perception and optimistic bias, with a weak effect suggesting the former affects the latter. Additional cross‐lagged analysis using structural equation modeling was used to look more closely at the components of optimistic bias (risk to self vs. risk to others). A significant and stronger potentially causal effect from risk perception to optimistic bias was found. Analysis of the experience and demographic variables’ effects on risk perception and optimistic bias, and their change, provided mixed results. The lessening of risk perception and increase in optimistic bias over the period of quiescence suggest that risk communicators and emergency managers should direct attention toward reversing these trends to increase disaster preparedness.  相似文献   
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An introduction is provided to this Social Development Quartet in which the articles focus on parent emotion socialization in the context of psychopathology and risk. In two articles, the samples of children and/or adolescents have a psychiatric diagnosis [oppositional defiant disorder (ODD) or depressive disorder]. The other two articles feature samples in which children and families have experienced serious risks [exposure to inter‐parental violence (IPV) or maternal incarceration]. The articles in this Social Development Quartet extend our knowledge of the impact of parental emotion socialization practices to contexts in which children and parents experience higher than normative risks. The work reported in these articles builds upon research on emotion socialization in normative contexts, illustrating the buffering effects of supportive parenting as well as its limits.  相似文献   
30.
Newspapers published by Roman Catholic dioceses represent a large and unexplored part of the religious publishing industry. This study attempts to shed light on the challenges these publications face by examining the readership of a diocesan newspaper in a large Catholic diocese in the Mid-Atlantic region of the United States. Based on a comprehensive survey of 24,278 Roman Catholic households from 27 parishes throughout the diocese, this study finds a large gap in readership and engagement between older and younger readers, raising important strategic and pastoral questions for the newspaper in the years to come.  相似文献   
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