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781.
T Karlsmark H K Thomsen L Danielsen O Aalund O Nielsen K G Nielsen I K Genefke 《Forensic science international》1988,39(2):175-188
In order to establish pathological evidence in dermis for distinguishing between sequelae of electrical torture and those of other superficial injuries, the skin of eleven fully anaesthetized Danish Landrace pigs have been exposed to heat and electrical energy from either 50 Hz alternating current (a.c.) or direct current (d.c.) via 12 mm large contact knobs or via a pointed 0.5 mm large electrode (only 50 Hz a.c.). The lesions have been examined from 1 to 126 days after the injury. While heat lesions exposed to energy lower than 60 joule only gave minor changes, heat lesions exposed to more than 60 joule showed changes in both collagen fibres (basophilic or eosinophilic fibres without any birefringence or coarse cross-striation in polarized light, respectively) and dermal cells (granular cytoplasm). Areas exposed to 50 Hz a.c. via 0.5 mm. electrode showed basophilic collagen fibres and in a few biopsies on day 7 calcium salts on collagen fibres. Using 12 mm large electrodes the changes were minor, but basophilic and eosinophilic collagen fibres with no birefringence or with fine/coarse cross-striation respectively were seen. Even cells with 'vesicular nuclei' were seen on day 1 and 2 after the injury. The changes in the anode area showed resemblance to that of heat lesions (basophilic collagen fibres). Eosinophilic collagen fibres with fine densely spaced cross-striation in polarized light and 'vesicular nuclei' as well as collagen fibres with calcium salts were seen in the cathode lesions. It is concluded that the dermal changes in the cathode area are specific for electrical injury from day 1 to 14. However, earlier studies have demonstrated dermal changes specific for electrical injury at day 0 and the presence of calcified collagen fibres up to 2 months after injury. The dermal changes in anode lesions were non specific and could not be differentiated from those found in heat lesions. Alternating current lesions (50 Hz) were specific from day 1 to day 7, when the pointed electrode was used, but only in a few days when the energy was transferred via the 12-mm electrodes. 相似文献
782.
The polymorphism of the human vitamin D binding protein (Gc system) was investigated in a total of 149 sera from unrelated healthy Egyptians residing in Tanta City, Gharbiya Governorate, Nile Delta of Egypt, using isoelectric focusing (IEF) in thin-layer polyacrylamide gel followed by immunoblotting. The estimated gene frequencies were Gc1s = 0.540, Gc1f = 0.242 and Gc2 = 0.218. 相似文献
783.
Naoise Mac Giollabhui Johanna Nielsen Sam Seidman Thomas M. Olino Lyn Y. Abramson Lauren B. Alloy 《Journal of youth and adolescence》2018,47(10):2129-2142
Hopelessness is implicated in multiple psychological disorders. Little is known, however, about the trajectory of hopelessness during adolescence or how emergent future orientation may influence its trajectory. Parallel process latent growth curve modelling tested whether (i) trajectories of future orientation and hopelessness and (ii) within-individual change in future orientation and hopelessness were related. The study was comprised of 472 adolescents [52% female, 47% Caucasian, 47% received free lunch] recruited at ages 12–13 who completed measures of future orientation and hopelessness at five annual assessments. The results indicate that a general decline in hopelessness across adolescence occurs quicker for those experiencing faster development of future orientation, when controlling for age, sex, low socio-economic status in addition to stressful life events in childhood and adolescence. Stressful childhood life events were associated with worse future orientation at baseline and negative life events experienced during adolescence were associated with both an increase in the trajectory of hopelessness as well as a decrease in the trajectory of future orientation. This study provides compelling evidence that the development of future orientation during adolescence is associated with a faster decline in hopelessness. 相似文献
784.
Sevgi Bayram Özdemir Shuyan Sun Liliia Korol Metin Özdemir Håkan Stattin 《Journal of youth and adolescence》2018,47(6):1151-1163
Research on ethnic victimization to date has done little to identify the reasons why adolescents victimize their peers due to their ethnic background. To address this limitation, we examined: (1) the extent to which prejudiced attitudes within adolescents’ close and larger social networks determine their engagement in ethnic harassment, and (2) the extent to which classroom ethnic diversity plays a role in any such link. Our sample included 902 Swedish adolescents (M age ?=?14.40, SD?=?.95; 50.3% girls). We found that Swedish adolescents who held negative attitudes toward immigrants or who were surrounded by prejudiced peers were more likely to be involved in ethnic harassment, particularly in classrooms with high ethnic diversity. Adolescents in classrooms with a high anti-immigrant climate were more likely to harass their immigrant peers. These findings suggest that prejudiced beliefs in youth social networks put young people at risk of engaging in ethnic harassment, particularly in ethnically diverse classrooms. 相似文献
785.
Laura M. Padilla-Walker Sarah M. Coyne Savannah L. Kroff Madison K. Memmott-Elison 《Journal of youth and adolescence》2018,47(2):445-459
The goal of the current study was to examine the protective role that maternal media monitoring might have for adolescents. This was done by considering whether styles of media monitoring either directly reduced media use, or whether they buffered the associations between aggressive media use and adolescents’ prosocial behavior, aggression, and delinquency. Participants were 681 adolescents from two cities in the United States (51% female; 73% white), and their mothers, who provided data at two different time points, 2 years apart (when adolescents were roughly ages 13 and 15). Mixture modeling results revealed that mothers used four different styles of media monitoring made up of combinations of active and restrictive monitoring as well as forms of co-use. Styles that included active monitoring and connective co-use (i.e., engaging in media with the intent to connect with children) were directly associated with less media use, and moderated links between adolescents’ media use and behavioral outcomes concurrently but not longitudinally. The discussion was focused on the strength of considering multiple strategies of media monitoring together, and how this approach can inform future research in the area of parental media monitoring. 相似文献
786.
AliceAnn Crandall Brianna M. Magnusson M. Lelinneth B. Novilla 《Journal of youth and adolescence》2018,47(4):793-806
Adolescent self-regulation is increasingly seen as an important predictor of sexual risk-taking behaviors, but little is understood about how changes in self-regulation affect later sexual risk-taking. Family financial stress may affect the development of self-regulation and later engagement in sexual risk-taking. We examined whether family financial stress influences self-regulation in early adolescence (age 13) and growth in self-regulation throughout adolescence (from age 13–17 years). We then assessed the effects of family financial stress, baseline self-regulation, and the development of self-regulation on adolescent sexual risk-taking behaviors at age 18 years. Using a curve-of-factors model, we examined these relationships in a 6-year longitudinal study of 470 adolescents (52% female) and their parents from a large northwestern city in the United States. Results indicated that family financial stress was negatively associated with baseline self-regulation but not with growth in self-regulation throughout adolescence. Both baseline self-regulation and growth in self-regulation were predictive of decreased likelihood of engaging in sexual risk-taking. Family financial stress was not predictive of later sexual risk-taking. Intervening to support the development of self-regulation in adolescence may be especially protective against later sexual risk-taking. 相似文献
787.
Using interview and survey data, we argue there are three types of places in the rural United States, and that their social and economic conditions help us understand emerging political trends, including the rural support for Donald Trump. More rural votes were cast for the Republican presidential candidate in 2016 than in other recent elections, yet shifts to Republican votes were greatest in places undergoing the most significant economic transitions. Work in rural communities has been a source of pride and cultural identity for people as well as places, but many feel the new economy is not working for them. 相似文献
788.
Ian Scoones Marc Edelman Saturnino M. Borras Jr. Ruth Hall Wendy Wolford Ben White 《The Journal of peasant studies》2018,45(1):1-20
A new political moment is underway. Although there are significant differences in how this is constituted in different places, one manifestation of the new moment is the rise of distinct forms of authoritarian populism. In this opening paper of the JPS Forum series on ‘Authoritarian Populism and the Rural World’, we explore the relationship between these new forms of politics and rural areas around the world. We ask how rural transformations have contributed to deepening regressive national politics, and how rural areas shape and are shaped by these politics. We propose a global agenda for research, debate and action, which we call the Emancipatory Rural Politics Initiative (ERPI, www.iss.nl/erpi). This centres on understanding the contemporary conjuncture, working to confront authoritarian populism through the analysis of and support for alternatives. 相似文献
789.
Steven W. Hemelt Nathaniel L. Schwartz Susan M. Dynarski 《Journal of policy analysis and management》2020,39(3):686-719
Dual-credit courses expose high school students to college-level content and provide the opportunity to earn college credits, in part to smooth the transition to college. With the Tennessee Department of Education, we conduct the first randomized controlled trial of the effects of dual-credit math coursework on a range of high school and college outcomes. We find that the dual-credit advanced algebra course alters students’ subsequent high school math course-taking, reducing enrollment in remedial math and boosting enrollment in precalculus and Advanced Placement math courses. We fail to detect an effect of the dual-credit math course on overall rates of college enrollment. However, the course induces some students to choose four-year universities instead of two-year colleges, particularly for those in the middle of the math achievement distribution and those first exposed to the opportunity to take the course in eleventh rather than twelfth grade. We see limited evidence of improvements in early math performance during college. 相似文献
790.
Drew M. Anderson Katharine M. Broton Sara Goldrick-Rab Robert Kelchen 《Journal of policy analysis and management》2020,39(3):720-739
We conduct the first long-term experimental evaluation of a need-based financial aid program, the privately funded Wisconsin Scholars Grant. Over multiple cohorts, the program failed to increase degree completion and graduate school enrollment up to 10 years after matriculation. The program did reduce time-to-degree for some students and modestly increased the number of STEM degrees earned. The lack of robust effects raises important questions about the conditions necessary for financial aid to benefit students. 相似文献