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381.
Ming-Te Wang Angela Chow Jessica Lauren Degol Jacquelynne Sue Eccles 《Journal of youth and adolescence》2017,46(8):1821-1838
Students’ motivational beliefs about learning physical science are critical for achieving positive educational outcomes. In this study, we incorporated expectancy-value theory to capture the heterogeneity of adolescents’ motivational trajectories in physics and chemistry from seventh to twelfth grade and linked these trajectories to science-related outcomes. We used a cross-sequential design based on three different cohorts of adolescents (N?=?699; 51.5?% female; 95?% European American; M ages for youngest, middle, and oldest cohorts at the first wave?=?13.2, 14.1, and 15.3 years) coming from ten public secondary schools. Although many studies claim that physical science motivation declines on average over time, we identified seven differential motivational trajectories of ability self-concept and task values, and found associations of these trajectories with science achievement, advanced science course taking, and science career aspirations. Adolescents’ ability self-concept and task values in physics and chemistry were also positively related and interlinked over time. Examining how students’ motivational beliefs about physical science develop in secondary school offers insight into the capacity of different groups of students to successfully adapt to their changing educational environments. 相似文献
382.
Jessica Steinberg 《Journal of Gender Studies》2017,26(6):702-713
This paper examines perceptions of lower-class female prostitutes in eighteenth-century London. This study challenges the prevailing argument that these perceptions fundamentally changed from ‘lusty whores’ to victims of poverty. An examination of Bridewell records, sermons, pamphlets, and the newspaper press, reveals that commentators believed that lust, poverty, and greed collectively explained what drove women to prostitution. Commentators recognized that, unable to make ends meet, many women turned to prostitution to survive, while also suggesting that others turned to prostitution because they believed they could gain considerable wealth by doing so. These same commentators asserted that some women were unusually lustful and that only prostitution would satisfy their insatiable desires. The simultaneous depiction of prostitutes in contradictory ways suggests that prostitution was not offensive to Georgian Britons solely because it involved women exchanging sexual favours for money, but because prostitution transgressed Britons’ deepest sensibilities about morality. 相似文献
383.
Jessica M. McLamb M.S. Lara D. Adams M.S. Mark F. Kavlick Ph.D. 《Journal of forensic sciences》2020,65(6):1828-1834
A wet-vacuum-based collection method with the M-Vac® was compared to a wet-swabbing collection method by examining the recovery of diluted blood on 22 substrates of varying porosity. The wet-vacuum method yielded more total nuclear DNA than wet-swabbing on 18 porous substrates, recovering on average 12 times more DNA. However, both methods yielded comparable amounts of total DNA on two porous and two nonporous substrates. In no instance did wet-swabbing significantly recover more DNA. The wet-vacuum method also successfully collected additional DNA on previously swabbed substrates. Mitochondrial DNA yields were assessed, and outcomes were generally similar to the nuclear DNA outcomes described above. Results demonstrate that wet-vacuuming may serve as an alternative collection method to swabbing on difficult porous substrates and could potentially recover additional DNA on previously swabbed substrates. However, swabbing remains the preferred collection method on substrates with visible stains and/or nonporous surfaces for reasons of convenience, simplicity, and lower cost relative to the wet-vacuum method. 相似文献
384.
Journal of Chinese Political Science - Xi Jinping’s efforts to recentralize political power have triggered a debate over if these changes will destroy the “authoritarian... 相似文献
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388.
Jessica L. Hamilton Jonathan P. Stange Evan M. Kleiman Elissa J. Hamlat Lyn Y. Abramson Lauren B. Alloy 《Journal of youth and adolescence》2014,43(5):824-833
Early pubertal timing has been found to confer risk for the occurrence of interpersonal stressful events during adolescence. However, pre-existing vulnerabilities may exacerbate the effects of early pubertal timing on the occurrence of stressors. Thus, the current study prospectively examined whether cognitive vulnerabilities amplified the effects of early pubertal timing on interpersonal stress generation. In a diverse sample of 310 adolescents (M age = 12.83 years, 55 % female; 53 % African American), early pubertal timing predicted higher levels of interpersonal dependent events among adolescents with more negative cognitive style and rumination, but not among adolescents with lower levels of these cognitive vulnerabilities. These findings suggest that cognitive vulnerabilities may heighten the risk of generating interpersonal stress for adolescents who undergo early pubertal maturation, which may subsequently place adolescents at greater risk for the development of psychopathology. 相似文献
389.
Both substance use and obesity are prevalent among youth. As youth age, substance use rates increase and over the past three
decades, obesity rates among youth have tripled. While these two factors have both short- and long-term health impacts, little
research has explored how substance use and obesity among youth may be related. This study explores the bi-directional longitudinal
relationships between substance use and body composition. Participants (N = 704; 50.7% female) were mostly white (86.4%) with
a baseline mean age of 14.7 years. Objectively measured body composition was used to calculate body mass index z-scores (BMI
z-score) and percent body fat. Cross-lagged structural equation models, accounting for clustering at the school level, were
run to determine the longitudinal association between body composition and self-reported substance use (alcohol, cigarette,
and marijuana), adjusting for socio-demographic characteristics, pubertal status, and weight satisfaction. Baseline alcohol
use predicted decreased BMI z-score at follow-up and a similar association with percent body fat approached significance.
Baseline cigarette use predicted increased percent body fat. No longitudinal associations were seen between baseline body
composition and future substance use. Our results suggest that substance use contributes to subsequent body composition; however,
body composition does not contribute to subsequent substance use. Continued research that explores these relationships longitudinally
is greatly needed. 相似文献
390.
From 2000-2005, Somerville, MA, experienced a number of youth overdoses and suicides. The community response followed CDC recommendations for contagion containment. A community coalition, Somerville Cares About Prevention, became a pivotal convener of community partners and a local research organization, the Institute for Community Health, provided needed expertise in surveillance and analysis. Mayoral leadership provided the impetus for action while community activists connected those at risk with mental health resources. Using a variety of data sources (including death certificates, youth risk surveys, 911 call data, and hospital discharges) overdose and suicide activity were monitored. Rates of suicide and overdose for 10-24-year-olds were higher than in previous years. Using case investigation methods, the majority of suicide victims were found to be linked through common peer groups and substance abuse. Subsequent community action steps included: a community-based trauma response team, improved media relationships, focus groups for suicide survivors, and prevention trainings to community stakeholders. Youth suicide and overdose activity subsided in May of 2005. The community partnerships were critical elements for developing a response to this public health crisis. This collaborative approach to suicide contagion used existing resources and provides important lessons learned for other communities facing similar circumstances. 相似文献