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271.
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
272.
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
273.
In order to better understand why some children retaliate when they feel provoked and others do not, the present study identified “pacifistically-oriented” children who made negative interpretations in response to unambiguous provocations, yet did not endorse revenge goals, and compared them to “revenge-seeking” children who also made negative interpretations but did endorse revenge goals. Groups were identified based on seventh graders’ (N?=?367; 54.77% male; 22.89% racial/ethnic minority) responses to hypothetical situations in which a peer excluded and insulted them. Comparing these groups revealed that Pacifists endorsed relationship-maintaining goals and emotion regulation goals more highly than Revenge-Seekers. Revenge-Seekers reported more anger and endorsed beliefs about negative reciprocity and aggression being legitimate more highly than Pacifists. Additionally, Revenge-Seekers were more disrespect sensitive than were Pacifists, based on a measure of vigilance for signs of disrespect and expectations that others would disrespect them. Together these findings point to social-cognitive and emotion-related processes that may inhibit revenge-seeking in unambiguous provocation situations, even when children interpret the peer’s behavior quite negatively. 相似文献
274.
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
275.
Greenlee Jill S. Nteta Tatishe M. Rhodes Jesse H. Sharrow Elizabeth A. 《Political Behavior》2020,42(3):655-695
Political Behavior - Throughout her 2016 U.S. presidential campaign, Democratic Party nominee Hillary Clinton crafted messages intended to appeal to fathers of daughters and to highlight the... 相似文献
276.
Public Choice - Numerous studies—operating with diverse model specifications, samples and empirical measures—suggest different economic, social, cultural, demographic, institutional and... 相似文献
277.
The U.S. electric power sector has experienced a substantial shift of the generation mix since the turn of the century, moving from heavy reliance on coal‐powered generation to one drawing more from natural gas and, more recently, renewables. This transition has been forged by a mix of macroeconomic factors (recession and recovery); technological breakthroughs (horizontal drilling coupled with hydraulic fracturing; improvements in natural gas plant efficiency); clean energy policies at federal, state, and local levels of government; and private sector demands for carbon‐free energy sources. These factors have combined to reduce carbon emissions from electric power generation substantially this century. In this article we examine the extent of this transition, its causes, as well as the distinct American institutional factors steering it, including energy and environmental federalism, electoral politics, and the political economy of clean energy policy enactment and resistance. 相似文献
278.
Steven Roberts 《Journal of Gender Studies》2018,27(3):274-287
AbstractDrawing on a seven-year longitudinal qualitative study in England, this paper presents evidence of how engagement with housework and childcare is regular and normalized for contemporary working-class young adult men. I explain this development with reference to inclusive masculinity theory, but supplement this by incorporating Mannheim’s concept of social generation, as recently adopted by scholars of youth sociology. The paper thus further augments other research that has documented considerable change in the construction and performance of contemporary masculinities – such as an opening up of gendered behaviours and a decrease (but not erasure) of homophobia – among young men across multiple contexts in English-speaking countries. 相似文献
279.
Although the use of truth and reconciliation commissions (TRCs) has grown considerably over the last 3 decades, there is still
much that we do not know concerning the choice and the structuring of TRCs. While the literature has focused primarily on
the effects of TRCs, we examine the domestic and the international factors influencing the choice of a commission in sub-Saharan
Africa from 1974 to 2003 using pooled cross-sectional time series. We find that states which adopted a TRC prior to South
Africa were generally repressive centralized regimes which used the truth commission as political cover. However, since South
Africa’s TRC, democratizing states have been more likely to adopt a truth commission as a form of transitional justice.
相似文献
Lilian A. BarriaEmail: |
280.
Stephanie H. Parade Esther M. Leerkes A. Nayena Blankson 《Journal of youth and adolescence》2010,39(2):127-137
The current study examined the process by which attachment to parents influences satisfaction with and ease in forming friendships
at college. One hundred seventy-two female college freshmen completed a measure of parental attachment security the summer
before their first semester of college (July 2006) and measures to assess satisfaction with and ease in forming close relationships
at the end of their first semester (December 2006). Students ranged in age from 18 to 20 years (M = 18.09, SD = 0.33) and were diverse in their racial makeup (30% racial minority). Consistent with predictions derived from
attachment theory, secure attachment to parents was positively associated with ease in forming friendships among racial minority
and white participants and satisfaction with friendships among minority participants. Moreover, indirect effects of parental
attachment security on relationship outcomes through social anxiety were significant for minority participants but not for
white participants. Findings may be useful in the development of retention programs targeted at incoming university freshmen,
particularly minority students. 相似文献