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1.
National Park of Tijuca in Rio de Janeiro (Brazil) is about 3,300 ha and considered the largest urban forest in the world. Its floristic composition is typical of Atlantic Rain Forest. The reserve is being altered because of fire occurrences and urban expansion. This study identified locations and causes of forest fires, and makes management recommendations to restore damaged areas. From 1991 to 2000, forest firefighters recorded an average of 75-fire occurrences/year. Identified causes included hot air balloons (24%), intentional (24%), rubbish burning (21%) and religious practices (17%). Primary fuels included invasive grasses and ferns. Although hot air balloons destroyed larger areas of forest in each occurrence, a greater number of fires started in the invasive vegetation along roads that bisect the forest. In response to recurrent forests, invasive vegetation has spread gradually into the forest increasing forest degradation. To decrease fire damage, sites with high fire frequencies and density of invasive vegetation were planted with less flammable species. Results indicate that fire frequency decreased and density of invasive vegetation declined. This approach appears to prevent fire incidence, reduce the need for fire fighting, and preserve existing biodiversity.  相似文献   
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Latina female (n= 97) and Latino male (n= 69) college students (M age = 21.4 years) completed self‐report surveys regarding family of origin experiences, including sexual communication with parents while growing up. Latino parents of this comparatively highly educated sample tended to use direct rather than indirect strategies for communicating about sexuality with their children. Young women reported higher levels of sexual communication with mothers while growing up than did young men, and respondents reported less communication with fathers than mothers. Among young women, sexual communication with mother was positively associated with non‐Mexican origin and negatively associated with having older brothers living at home. In contrast, maternal education was positively associated with mother‐son communication about sex. Paternal education and the absence of older brothers positively predicted communication with both sons and daughters. The analyses provide novel information regarding sexual communication in Latino families and suggest directions for future research.  相似文献   
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The relation between personality and subjective well-being (SWB) remains involved in a considerable ambiguity and the numerous studies conducted have neglected an approach at a more detailed level of analysis. This study explores the idea that neuroticism, extraversion and conscientiousness facets predict differentially each SWB component. A battery of self-report questionnaires was used to assess personality and SWB in 398 teachers of primary and high schools. Findings of a cross-sectional study showed that neuroticism, extraversion and conscientiousness facets contributed to significantly explain the variance in positive affect, negative affect and life satisfaction. Moreover, these facets predicted differentially each of the three SWB components. At same time, this study corroborates two important premises: the specificity of facets as discrete traits and the independence of the three SWB components.  相似文献   
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The linkages between self‐regulation in childhood, risk proneness in early adolescence, and risky sexual behavior in mid‐adolescence were examined in a cohort of children (N=518) from the National Longitudinal Survey of Youth. The possible mediating role of two early adolescent variables (substance use and negative peer pressure) was also examined. Self‐regulation was assessed by maternal report at ages 8–9, and risk proneness, comprising aspects of sensation seeking and decision making, was assessed by adolescent self‐report at ages 12–13. Structural equation models predicting risky sexual behavior at ages 16–17 indicated that self‐regulation operated partly through early adolescent substance use, whereas risk proneness operated through early adolescent substance use and negative peer pressure. The overall model did not differ significantly for boys and girls, although there were gender differences in the strength of particular paths. These long‐term longitudinal results support the importance of early self‐regulation and risk proneness in setting the stage for adolescent sexual risk taking and implicate substance use and negative peer pressure as processes through which risk proneness and poor self‐regulation lead to risky sexual behavior.  相似文献   
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The authors examined relations among different measures of acculturation, and between acculturation and sexual behavior, in a sample of female Cuban American college students (n=61, M age = 18.4 years) who completed self-report surveys. In the first set of analyses, weak to moderate associations emerged among 4 measures of acculturation (birthplace, childhood language use, current language use, and ethnic identity), suggesting that inconsistent findings from prior research may have resulted from measurement limitations. In multivariate analyses, the authors examined predictors of sexual behavior and found that 1 aspect of acculturation (higher levels of ethnic identity) and background characteristics (being older and less religious) were associated with voluntary sexual intercourse. Moreover, higher levels on a sexual risk composite were associated with being born in the United States, more ethnically identified, older, and less religious. These analyses highlight the need for specificity in assessing acculturation in a college student population and support the need to examine cultural factors directly in sexuality research.  相似文献   
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This article estimates the value of a statistical life (VSL) for Chile under the hedonic wage method while accounting for individual risk preferences. Two alternative measures of risk aversion are used. First, risk aversion is directly measured using survey measures of preferences over hypothetical gambles, and second, over observed individual behaviors that may proxy for risk preferences, such as smoking status, are used. I reconcile the results with a theoretical model of economic behavior that predicts how the wage‐risk tradeoff changes as risk aversion differs across individuals. The VSL estimates range between 0.61 and 8.68 million dollars. The results using smoking behavior as a proxy for risk attitudes are consistent with previous findings. However, directly measuring risk aversion corrects the wage‐risk tradeoff estimation bias in the opposite direction. The results are robust to other observed measures of risk aversion such as drinking behavior and stock investments. Results suggest that, consistent with the literature that connects smoking behavior with labor market outcomes, smoking status could be capturing poor health productivity effect in addition to purely risk preferences.  相似文献   
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In this paper, we extend the censored linear regression model with normal errors to Student-t errors. A simple EM-type algorithm for iteratively computing maximum-likelihood estimates of the parameters is presented. To examine the performance of the proposed model, case-deletion and local influence techniques are developed to show its robust aspect against outlying and influential observations. This is done by the analysis of the sensitivity of the EM estimates under some usual perturbation schemes in the model or data and by inspecting some proposed diagnostic graphics. The efficacy of the method is verified through the analysis of simulated data sets and modelling a real data set first analysed under normal errors. The proposed algorithm and methods are implemented in the R package CensRegMod.  相似文献   
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