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801.
The cultural context in which rural farm children are raised has a significant effect on their lives. Researchers have traditionally viewed rural environments from a deficit perspective. Yet many children demonstrate resilience even in the face of significant adversity. This article focuses on strengths of rural farming communities in providing a cultural context that supports healthy development in children. It also notes practice considerations for child welfare in small agricultural communities.  相似文献   
802.
A wide range of data are obtained with self-report. Information obtained from persons using substances is generally reliable and valid, however, many studies show that some proportion of self-reports regarding substance use are inaccurate. This study examines self-reported response distortion in adolescents who received a brief intervention to reduce their smoking. Findings indicate that age and ethnicity of respondent may influence reported response distortion. Factors that appear to influence under- and over-reporting include social desirability and fear of repercussion. Response distortion does not appear to affect rated usefulness of the intervention, nor does intervention type appear to influence whether respondents thought the researcher wanted them to report less use. Results point to the need for further research regarding adolescents and response distortion.  相似文献   
803.
We investigate how inequalities in political participation are shaped across generations by considering the influence of family background-in particular, parents' education and political involvement-on political participation. We pursue this issue, first, for individuals, investigating the effects of parental characteristics on the participatory profile of their offspring. Then, we use what we have learned to understand how group differences in political participation-between women and men and among Latinos, African Americans, and Anglo Whites-are rooted in the legacy of class and political background and in experiences throughout the life cycle. They are co-authors of The Private Roots of Public Action: Gender, Equality, and Political Participation (Cambridge: Harvard University Press, 2001) which was the co-writer of the Victoria Schuck Award of the American Political Science Association for the best book on gender and politics of its year.  相似文献   
804.
805.
Given a random sample(X1, Y1), …,(Xn, Yn) from a bivariate (BV) absolutely continuous c.d.f. H (x, y), we consider rank tests for the null hypothesis of interchangeability H0: H(x, y). Three linear rank test statistics, Wilcoxon (WN), sum of squared ranks (SSRN) and Savage (SN), are described in Section 1. In Section 2, asymptotic relative efficiency (ARE) comparisons of the three types of tests are made for Morgenstern (Plackett, 1965) and Moran (1969)BV alternatives with marginal distributions satisfying G(x) = F(x/θ) for some θ≠ 1. Both gamma and lognormal marginal distributions are used.  相似文献   
806.
In some areas where oxygenated fuel programs have been implemented, there have been widespread complaints of non-specific health effects attributed to the gasoline. There are a number of hypotheses that can account for this apparent association. This paper examines the hypothesis that the use of oxy-fuel (either oxygenated gasoline or reformulated gasoline) results in exposure of the general population to one or more chemicals at concentrations that cause toxicologic injury. Although several oxygenates can be used in oxy-fuels, this analysis focuses on MTBE because it is the most widely used oxygenate and because the database of relevant toxicologic data is greatest for this oxygenate. The causal assessment is based on an evaluation of the qualitative and quantitative plausibility that oxygenated fuel-related exposures have toxicological effects, and the epidemiologic studies that directly test the hypothesis that the use of oxygenated fuels causes adverse health effects. The plausibility that chemical exposures related to oxy-fuel use cause toxicological effects is very low. This determination is based on consideration of the exposure-response and time-action profiles for relevant toxicological effects of MTBE in animals, experimental MTBE exposure studies in humans, and the possibility that the addition of MTBE to gasoline results in toxicologically significant qualitative and/or quantitative changes in gasoline-related exposures. Similarly, the epidemiologic studies of oxy-fuel exposed cohorts do not support a causal relationship between oxy-fuel use and adverse health effects. Although the data are insufficient to rule the possibility of unique sensitivity in a small segment of the population, the strength of the evidence and the availability of other more plausible explanations for the health complaints reported in association with oxy-fuels support a high degree of confidence in the conclusion that MTBE-containing oxygenated fuels are not the cause of acute toxicity in the general population.  相似文献   
807.
Puerto Rican children are more likely to have asthma than children in any other racial/ethnic group in the United States, yet little research has examined the factors contributing to childhood asthma among Puerto Ricans. Using data from a representative sample of mainland Puerto Rican children, the present study investigates the relationship between preterm birth and early-childhood asthma (i.e., in the first years of life). The roles of other risk factors (i.e., socioeconomic and demographic characteristics, environmental conditions, and maternal health behavior) in the development of asthma in early childhood also are considered. The analysis reveals a relatively high rate of asthma for preterm children as well as differences between term and preterm children in the risk factors for early-childhood asthma. Measures of socioeconomic status and the cleanliness of the home environment are related to asthma for term, but not preterm, children; in contrast, demographic characteristics and maternal health behavior are important risk factors for asthma among preterm children.  相似文献   
808.
Differential life experiences associated with race may critically affect the balance between physical and psychological well-being. This study investigated an age-related and disease-related symptom, restless sleep, among older African American and white members of two sociodemographically matched cohorts, community-dwelling older adults and older adults with chronic renal failure undergoing maintenance dialysis therapy. Sleep behaviors reflect age-dependent and disease-dependent homeostatic and circadian state regulation but are also socioculturally patterned. As hypothesized, restless sleep was significantly more characteristic of the older adults in the chronic disease cohort. With non-renal health conditions, depressed mood, perceived health, medication use, and sociodemographic variables controlled, however, African Americans were significantly less likely than whites in the chronic disease cohort to report restless sleep. African American and white patients differed in their expression of public and private religiousness, which in turn were associated, respectively, with depressed mood and restless sleep complaint. In addition, we suggest that differences for African American and white patients in the environmental exposure of chronic dialysis therapy, including African Americans' greater social integration within the dialysis treatment setting, contributed to their being less at risk than their white peers for subjective perception of sleep decay, a marker of overall well-being.  相似文献   
809.
810.
The purpose of this study was to determine whether a theory-based framework could be used to deductively identify and understand the characteristics of motivational leaders of physical activity groups for older adults. Participants were 23 older adults (mean age = 78.5 +/- 8.0 years, 65% women). An interview-guide approach was employed to elicit older adults' thoughts on important characteristics of physical activity group leaders. The data suggested that effective leaders are those whom the participants feel are properly qualified, are able to develop a personal bond with participants, and can use their knowledge and the group to demonstrate collective accomplishments. It was concluded that the findings could be used to extend the leadership activities beyond the traditional technical performance and individual feedback to include activities of social integration. Furthermore, the conceptual framework identified can serve as a valuable tool in guiding future researchers in their examination of leadership in physical activity groups for older adults.  相似文献   
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