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41.
Adolescents who do not conform to weight ideals are vulnerable to disapproval and victimization from peers in school. But, missing from the literature is a prospective examination of weight status and feelings of loneliness that might come from those experiences. Using data from the Québec Longitudinal Study of Child Development, we filled that gap by examining the prospective associations between loneliness and weight status when the sample was aged 10–13 years. At ages 10, 12, and 13 years, 1042 youth (572 females; 92% from French speaking homes) reported on their loneliness and were weighed and measured. Family income sufficiency was included in our analyses given its relationship with weight status, but also its possible link with loneliness during early adolescence. The findings showed that (1) weight status and loneliness were not associated concurrently; (2) weight status predicted increases in loneliness from ages 12 to 13 years; and (3) loneliness predicted increases in weight from ages 12 to 13 years among female adolescents, but weight loss among male adolescents. The fact that loneliness was involved in weight gain for females suggests that interventions focused on reducing loneliness and increasing connection with peers during early adolescence could help in reducing obesity.  相似文献   
42.
Friends provide important social contexts for student development. Research has shown that adolescent friends are similar to each other in their interest and values for different school subjects. Yet our current understanding does not extend to knowing whether selection, deselection, or socialization processes are responsible for this phenomena. Without this knowledge, it is very difficult for parents, teachers, and schools to know how and when to intervene. This study investigated selection, deselection, and socialization effects on adolescent students’ task values for academic (languages, math and science, and social sciences) and non-academic subject areas (the arts and physical education). A social network approach was used to examine two waves of annual data collected from school-based networks of adolescents in the first and second years of high school education in Finland (N?=?1419; female?=?48.6%; mean age at first measurement point?=?16). The results revealed that adolescents tended to select friends with similar levels of task values (friend selection) for the arts and physical education, but friends did not become more similar in these areas over time (friend socialization). In contrast, there was evidence of friend socialization, but not friend selection, for the academic school subjects. Across all subjects, differences in task values did not predict friendship dissolution (friend deselection). These findings suggest that to a significant extent, students make agentic choices in developing friendship with schoolmates based on their task values in non-academic subjects. The resultant friend contexts that individuals created, in turn, affected their task values in academic subject areas. These results shed light on the complexity of friend effect mechanisms on task values at the subject domain-specific level.  相似文献   
43.
Revisiting Adjusted ADA Scores for the U.S. Congress, 1947-2007   总被引:1,自引:0,他引:1  
Philip Habel Department of Political Science, Southern Illinois University Carbondale, Mailcode 4501, Carbondale, IL 62901 This paper replicates and extends Groseclose, Levitt, and Snyder,"Comparing Interest Group Scores Across Time and Chambers: AdjustedADA Scores for the U.S. Congress," which appeared in the AmericanPolitical Science Review (1999/93:33–50). We replicatethe most recent unpublished extension by Dr. Groseclose andresearch assistants for years 1947–1999, and then we extendthe analysis to include years 2000 through 2007. We make availableinflation-adjusted ADA scores from 1947 through 2007, allowingscholars to incorporate the most recent interest group scoresinto their analyses. Author's Note: Authors are listed alphabetically. The authorswish to thank Tim Groseclose for making available both the nominalADA scores from 1947 to 1999 and the Matlab program files usedin this analysis. SA gratefully acknowledges the support ofthe Hoover Institution during her time there as the 2006–07W. Glenn Campbell and Rita Ricardo-Campbell National Fellowand the Robert Eckles Swain National Fellow. PH wishes to thankboth the Dirksen Congressional Center and the National ScienceFoundation, doctoral dissertation improvement division grant493469, for their generous support. He also wishes to acknowledgethe valuable research assistance of James Lewis, Joshua Mitchell,and Matt Bergbower. Special thanks to J. Tobin Grant, ScottMcClurg, and Wendy Tam Cho for their helpful feedback and assistance.All errors are the responsibility of the authors. Replicationmaterials and programs are available on the Political AnalysisWeb site.  相似文献   
44.
Few studies have examined risk factors of childhood and early adolescent depressive symptomatology trajectories. This study examined self-report depressive symptomatology across a 6-year time period from 2nd to 8th grade to identify latent groups of individuals with similar patterns of depressive phenomena in a sample of 951 children (440 girls, 511 boys). Analyses, using semiparametric group modeling (SGM), identified 5 trajectory groups for girls and boys: low depressed stables, low depressed risers, mildly depressed stables, moderately depressed changers, and moderately depressed risers. Individual risk factors, with the exception of shy/withdrawn behavior, were significantly different across trajectory group membership for boys and girls, as was low-income status for boys. Boys in the low depressed and mildly depressed stable trajectory groups had significantly higher levels of antisocial behavior, attention problems, and lower social competency compared to girls in similar groups. These results suggest that universal prevention programs implemented in early elementary school that target selected risk factors may be helpful in reducing future adolescent mental health problems, specifically depressive symptomatology.  相似文献   
45.
This study examined the effects of neighborhood context on juvenile recidivism to determine if neighborhoods influence the likelihood of reoffending. Although a large body of literature exists regarding the impact of environmental factors on delinquency, very little is known about the effects of these factors on juvenile recidivism. The sample analyzed includes 7,061 delinquent male juveniles committed to community-based programs in Philadelphia, of which 74% are Black, 13% Hispanic, and 11% White. Since sample youths were nested in neighborhoods, a hierarchical generalized linear model was employed to predict recidivism across three general categories of recidivism offenses: drug, violent, and property. Results indicate that predictors vary across the types of offenses and that drug offending differs from property and violent offending. Neighborhood-level factors were found to influence drug offense recidivism, but were not significant predictors of violent offenses, property offenses, or an aggregated recidivism measure, despite contrary expectations. Implications stemming from the finding that neighborhood context influences only juvenile drug recidivism are discussed.  相似文献   
46.
Sociometric nominations, social cognitive maps, and self-report questionnaires were completed in consecutive years by 327 students (56% girls) followed longitudinally from grade 7 to grade 8 to examine the stability of social standing in peer groups and correlates of changes in social standing. Social preference, perceived popularity, network centrality, and leadership were moderately stable from grade 7 to grade 8. Alcohol use and relational aggression in grade 7 predicted changes in social preference and centrality, respectively, between grade 7 and grade 8, but these effects were moderated by gender and ethnicity. Changes in social standing from grade 7 to grade 8 were unrelated to grade 8 physical aggression, relational aggression, and alcohol use after controlling for the grade 7 corollaries of these behaviors. Results are discussed in terms of their implications for understanding links between social standing and problem behaviors during adolescence.
Jennifer E. LansfordEmail:
  相似文献   
47.
It is becoming increasingly accepted, not least by the Prime Minister and opposition leadership, that the negotiation of a comprehensive trade relationship with the EU is necessary to prevent the UK economy falling off a ‘cliff edge’. This concern is shaping the UK's strategy towards negotiations with the EU and has provided at least part of the motivation for the UK to consider requesting a transition period to facilitate the Brexit process. But how accurate are these fears? What evidence is there for the existence of a ‘cliff edge’? How disastrous would it be for the UK to revert to trading with the EU on the same basis as most other countries in the world, namely according to World Trade Organisation rules? This article seeks to address these issues and it highlights a number of implications for policy makers which flow from understanding the available evidence a little more clearly.  相似文献   
48.
Are internalizing and externalizing behavior problems interrelated via mutually reinforcing relationships (with each behavior leading to increases over time in levels of the other behavior) or mutually suppressing relationships (with each behavior leading to decreases over time in levels of the other behavior)? Past research on the directionality of these relationships has led to ambiguous results, particularly in adolescence. Furthermore, the extent to which prior results will generalize to adolescents with low levels of cognitive abilities remains unknown. This second limit is particularly important, given that these adolescents are known to present higher levels of externalizing and internalizing behaviors than their peers with average-to-high levels of cognitive abilities, and that the mechanisms involved in the reciprocal relationships between these two types of behaviors may differ across both populations. This study examines the directionality of the longitudinal relationships between externalizing and internalizing behavior problems as rated by teachers across three measurement waves (corresponding to Grades 8–10) in matched samples of 138 adolescents (34.78?% girls) with low levels of cognitive abilities and 556 adolescents (44.88?% girls) with average-to-high levels of cognitive abilities. The results showed that the measurement structure was fully equivalent across time periods and groups of adolescents, revealing high levels of developmental stability in both types of problems, and moderately high levels of cross-sectional associations. Levels of both internalizing and externalizing behaviors were higher among adolescents with low levels of cognitive abilities relative to those with average-to-high levels of cognitive abilities. Finally, the predictive analyses revealed negative reciprocal longitudinal relationships (i.e., mutually suppressing relationships) between externalizing and internalizing problems, a result that was replicated within samples of adolescents with low, and average-to-high levels of cognitive ability.  相似文献   
49.
The past decade has witnessed an intensifying focus on the development of irrigation in sub-Saharan Africa. It follows a 20-year hiatus in the wake of disappointing irrigation performance during the 1970s and 1980s. Persistent low productivity in African agriculture and vulnerability of African food supplies to increasing instability in international commodity markets are driving pan-African agricultural investment initiatives, such as the Comprehensive Africa Agricultural Development Programme (CAADP), that identify as a priority the improvement in reliability of water control for agriculture. The paper argues that, for such initiatives to be effective, there needs to be a re-appraisal of current dynamics of irrigation development in sub-Saharan Africa, particularly with respect to the role of small-scale producers’ initiatives in expanding irrigation. The paper reviews the principal forms such initiatives take and argues that official narratives and statistics on African irrigation often underestimate the extent of such activities. The paper identifies five key characteristics which, it argues, contradict widely held assumptions that inform irrigation policy in Africa. The paper concludes by offering a definition of ‘farmer-led irrigation’ that embraces a range of interaction between producers and commercial, government and non-government agencies, and identifies priority areas for research on the growth potential and impact of such interactions and strategies for their future development.  相似文献   
50.
This article offers an overview of the literature on international democracy promotion in relation to the Middle East and North Africa (MENA). It draws on the criteria of process tracing to evaluate the mechanisms, processes and episodes of democratization associated with international democracy promotion in the region. It finds that the literature lacks a clear account of how international democracy promotion relates to conditions for democratization and could pay greater attention to the role of media in either supporting or counteracting democracy promotion activities which impact democratization processes in the region.  相似文献   
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