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981.
This research contributes to an understanding of the relationship between climate change, economic impacts and migration. We model the long-term relationship (up to 45 years of projection) between demographic dynamics—particularly migration—driven by changes in the performance of the economy due to climate changes in the Northeast region of Brazil. The region is of particular relevance to the study of climate change impacts given its large human population (28% of Brazil’s population) and high levels of impoverishment, having an extensive semi-dry area which will be severely impacted by growing temperatures. Ultimately, the integrated model generates state- and municipal-level migration scenarios based on climate change impacts on the primary economic sectors and their articulations with other sectors. Results suggest that the predicted climate changes will impact severely the agriculture sector in the region, acting as a potential migration push factor to other regions in the country. Finally, we discuss how the increased vulnerability of some groups, particularly migrants, can be factored into Brazilian public policy and planning.  相似文献   
982.
This study tests theoretical arguments about gender differences in scientific knowledge and environmental concern using 8 years of Gallup data on climate change knowledge and concern in the US general public. Contrary to expectations from scientific literacy research, women convey greater assessed scientific knowledge of climate change than do men. Consistent with much existing sociology of science research, women underestimate their climate change knowledge more than do men. Also, women express slightly greater concern about climate change than do men, and this gender divide is not accounted for by differences in key values and beliefs or in the social roles that men and women differentially perform in society. Modest yet enduring gender differences on climate change knowledge and concern within the US general public suggest several avenues for future research, which are explored in the conclusion.  相似文献   
983.
Recent developments in educational transitions research suggest a decomposition of qualitative dimensions within educational levels that are (nearly) universal. However, research on long-term trends of social stratification in the structurally tracked educational system of the Netherlands has not been published previously. In the Netherlands, the secondary educational level is divided into four hierarchical tracks which each lead to different options for subsequent educational decisions. A rapid increase of participation in the higher tracks over time however, may have changed the background-specific distribution of early track placement. This paper improves upon previous research on educational inequality by incorporating a long-term perspective into tracking research. The secondary level of the Dutch educational system is decomposed into its four tracks, using a time frame that covers cohorts that entered secondary education between 1946 and 1998. The application of multinomial logit regressions reveals that the choice of a secondary track is strongly depending on social background features, measured as education of the parents and occupational status of the father. We found linear downward trends of effects for fathers’ occupation in the intermediate tracks for the cohorts that entered secondary education between WWII and the 90s. The effects of parental education also decrease after WWII, but the trend is curvilinear and not enduring. Unexpectedly, the effects almost reach their previous level in the youngest cohort. Our results furthermore suggest that a controversial reform of the educational system in 1968 neither triggered nor accelerated equalization of secondary education, although it resulted in a growth of participation in senior general education (HAVO).  相似文献   
984.
This study introduces the Satisfaction with Life Scale adapted for Children (SWLS-C) and presents psychometric findings regarding its validation. The SWLS-C was adapted from the Satisfaction with Life Scale (SWLS; Diener et al. 1985), which is one of the most commonly used measures to assess satisfaction with life in adults. Three subject matter experts adapted the SWLS by changing the wording of the item stem and response format in order to make it more understandable for children. A stratified random sample of 1,233 students (48% girls) in grades 4–7 (mean age 11 years and 7 months) provided data on the SWLS-C and measures of optimism, self-concept, self-efficacy, depression, emphatic concern, and perspective taking. The SWLS-C demonstrated a unidimensional factor structure and high internal consistency. Furthermore, differential item functioning and differential scale functioning analyses indicated that the SWLS-C measures satisfaction with life in the same way for different groups of children (i.e., with regard to gender, first language learned at home—English vs. other language(s) than English—and across different grades) at the item and at the scale level. Associations between scores on the SWLS-C and demographic variables were statistically non-significant or of small effect size. In addition, the SWLS-C showed evidence of convergent and discriminant validity in relation to the other measures. Our results indicate that the SWLS-C is a psychometrically sound instrument that demonstrated evidence of construct validity for this age group. Limitations and future directions are discussed.  相似文献   
985.
Using behavioral self-regulation processes may facilitate exercise among older women with heart disease. Data from women in a heart disease-management program (n = 658, mean 73 years), was used to explore associations among exercise self-regulation components (i.e., choosing to improve exercise and observing, judging, and reacting to one's behavior) and exercise capacity. General linear models showed that choosing exercise predicted higher exercise self-regulation scores postprogram and 8 months later. In turn, these scores predicted greater improvements in exercise capacity concurrently and 8 months later. Interaction analyses revealed that the effect of self-regulation on exercise capacity was stronger among women who chose to work on exercise.  相似文献   
986.
Students recruited from psychology undergraduate university populations are commonly used in psychology research, including gambling studies. However, the extent to which the use of this subpopulation produces findings that can be extrapolated to other groups is questionable. The present study was designed to compare results from university-recruited psychology student gamblers to those obtained from a sample of gamblers recruited from the general population that also included students. An online survey measuring gambling behavior and Internet gambling, attitudes and knowledge about gambling and problem gambling severity was posted on websites accessed by gamblers. Participants were recruited from two sources, a psychology undergraduate university population (n = 461) and online websites (n = 4,801). Results showed university-recruited students differed significantly from both adults and students recruited from the general population in respect to demographic variables and gambling behavior. Psychology undergraduate students were younger, more likely to be female, and had lower incomes. When relevant demographic variables were controlled, psychology undergraduate students were found to gamble less frequently, at different times, and to be at lower-risk for gambling-related problems, but had more irrational beliefs and more negative attitudes towards gambling than gamblers recruited from the general population. Results suggest that caution should be used in extrapolating findings from research using university-recruited psychology student gamblers to wide community populations due to differences related to gambling thoughts, attitudes and behaviors.  相似文献   
987.
The fifth revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) is scheduled for publication in 2013. It will include several changes to the diagnosis of pathological gambling: the name of the disorder will be altered, the threshold for diagnosis will decrease, and one criterion will be removed. This paper reviews the rationale for these changes and addresses how they may impact diagnosis and treatment of the disorder, as well as potential for future research in the field.  相似文献   
988.
Cognitive perspectives on gambling propose that biased thinking plays a significant role in sustaining gambling participation and, in vulnerable individuals, gambling problems. One prominent set of cognitive biases include illusions of control involving beliefs that it is possible to influence random gaming events. Sociologists have reported that (some) gamblers believe that it is possible to throw dice in different ways to achieve gaming outcomes (e.g., ‘dice-setting’ in craps). However, experimental demonstrations of these phenomena are lacking. Here, we asked regular gamblers to roll a computer-simulated, but fair, 6 sided die for monetary prizes. Gamblers allowed the die to roll for longer when attempting to win higher value bets, and when attempting to hit high winning numbers. This behaviour was exaggerated in gamblers motivated to keep gambling following the experience of almost-winning in gambling games. These results suggest that gambling cognitive biases find expression in the motor behaviour of rolling dice for monetary prizes, possibly reflecting embodied substrates.  相似文献   
989.
Pollen specialization by solitary bees in an urban landscape   总被引:1,自引:1,他引:0  
Many polylectic bee species are known to specialize locally on one or a few pollen types to increase foraging efficiency. What is relatively unknown is how different landscapes influence foraging decisions, and whether habitat alteration, such as that resulting from urbanization, influences broad-scale foraging activities of bees. This study evaluates the type and diversity of pollen collected by two solitary bees that are common in Toronto, Ontario, Canada, the native Osmia pumila and the exotic O. caerulescens, sampled in trap nests set up in urban parks and gardens. We found that the dominant pollen in every successful brood cell was either of one widespread, cosmopolitan lawn-invasive plant species (Trifolium repens) or one of two wind-pollinated tree genera (Quercus spp. and Betula spp.). In combination, these three represented more than 90 % of all pollen collected by each bee species. Despite considerable overlap in the dominant pollen types collected by each bee species, the exotic O. caerulescens was significantly more specialized than the native O. pumila. Brood cells with Betula as the dominant pollen type were more pollen species-rich than those cells having Trifolium or Quercus as dominant, perhaps a result of the comparatively low protein content in Betula pollen.  相似文献   
990.
The percentage of female-headed African American families has increased significantly since the 1960s. It is now estimated that over half of all African American children will grow up in a female-headed household. This article examines factors related to the formation of these households as well as the challenges associated with these households. Policies and programs that have been implemented to treat these families are examined.  相似文献   
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