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181.
Postmortem stability of DNA 总被引:11,自引:0,他引:11
High-molecular-weight DNA was recovered postmortem in sufficient quantities from various human organ tissues as well as from blood, although not all organs were equally well suitable. Good DNA stability was found in brain cortex, lymph nodes and psoas muscle over a period of three weeks postmortem. Spleen and kidney showed good DNA stability up to five days postmortem but after longer periods, rapid degradation was observed. Yields of DNA from blood were not consistent because of the non homogeneity of samples. Blood clots were rich with DNA. Generally, the amount of degraded DNA correlated directly with the duration of the postmortem period. However in some cases, DNA degradation was already prominent after a short period. However in some cases, DNA degradation was already prominent after a short period. Case histories showed that high environmental temperature at the site of death and/or infectious diseases prior to death were the main factors for rapid autolysis. Gradual disappearance to complete loss of the long fragments (15-23 kb) was observed in DNA fingerprinting using the minisatellite probe 33.15. No extra-bands were noted, thus excluding erroneous conclusions. However, evidentiary value of older samples was lower. 相似文献
182.
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
183.
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
184.
Research suggests that fact checking corrections have only a limited impact on the spread of false rumors. However, research has not considered that fact-checking may be socially contingent, meaning there are social contexts in which truth may be more or less preferred. In particular, we argue that strong social connections between fact-checkers and rumor spreaders encourage the latter to prefer sharing accurate information, making them more likely to accept corrections. We test this argument on real corrections made on Twitter between Janurary 2012 and April, 2014. As hypothesized, we find that individuals who follow and are followed by the people who correct them are significantly more likely to accept the correction than individuals confronted by strangers. We then replicate our findings on new data drawn from November 2015 to February, 2016. These findings suggest that the underlying social structure is an important factor in the correction of misinformation. 相似文献
185.
Several developing countries are currently experiencing a significant fertility decline, however, academic economists have paid little attention to this transition. This paper seeks to explain the fertility transition by infant mortality, urbanisation, income, culture and educational attainment of females and males using annual data for 92 developing countries over the period 1960–2014. External instruments are used to deal with endogeneity. The results suggest that increasing per capita income, improved female education and increasing secularisation have been important determinants for declining fertility in the developing world. 相似文献
186.
The plural legal system in post-conflict Liberia expresses tensions between modern and customary institutions. This article seeks to understand how Liberians navigate choices in the plural legal system to address gender-based violence cases. By asking how and why people make the choices they do, we highlight how Liberians solve tensions between institutions, by creating flexible categories that allow them to pursue a course of action that does not compromise their ability to access social networks and resources. 相似文献
187.
Issar Daryanani Jessica L. Hamilton Brae Anne McArthur Laurence Steinberg Lyn Y. Abramson Lauren B. Alloy 《Journal of youth and adolescence》2017,46(1):213-227
Although research consistently suggests that adolescents in single-mother families are at increased risk for depression, the mechanisms that explain this relationship are unclear. In a community sample of adolescents (N?=?368; ages 12–16; 50?% female; 50?% White) and their mothers (42?% single), adolescents completed measures of depressive symptoms, rumination, and depressogenic inferential style at baseline and two yearly follow-ups. Mothers reported on stressful events that occurred in the child’s life from birth until baseline. Adolescents raised by single mothers, relative to partnered mothers, experienced more childhood stressors and higher rumination levels at 1-year follow-up. Additionally, higher rumination mediated the relationship between single motherhood and greater youth depressive symptoms at the 2-year follow-up. Clinical implications and developmental considerations are discussed. 相似文献
188.
Temitope B. Oriola 《冲突和恐怖主义研究》2017,40(2):99-121
The kidnapping of 276 girls at Government Secondary School Chibok, Borno State, Nigeria, on 14 April 2014 has brought into international prominence the organization Jama'atu Ahlis Suna Lidda'awati Wal Jihad or Boko Haram. This incident heralded a new trajectory in Boko Haram's tactics and strategies. This article focuses on Boko Haram's strategic deployment of sexual and gender-based violence (SGBV) against women. The gendered performativity of Boko Haram, its methodology for sourcing for women and young girls, and its concomitant utilitarian/instrumental approach vis-à-vis SGBV against women are analyzed against the backdrop of the political economy and patriarchal ideational infrastructure of the Nigerian society. The article argues that Boko Haram's deployment of SGBV against women is an extension of the “repertoire of violence” ingrained in the sociopolitical and cultural milieu of Boko Haram's primary area of operation. Boko Haram's instrumental approach to SGBV is fourfold and hinges on the sociobiological utility of women. Boko Haram construes women as the bearers of its future despite its brutality toward them. The consequence is a strategic plan for procreation of a new generation of children raised through the cyclical constellation of mass rape of women, consequent impregnation and kidnapping the offspring of such rapes. Overall, this article contributes to the burgeoning scholarly literature on Boko Haram's terrorist activities. 相似文献
189.
Frank B. Wilderson III 《Women & Performance》2017,27(1):104-111
This essay expands Saidiya Hartman's unflinching paradigmatic analysis in Scenes of Subjection of the modes of historical continuity in which Black women are barred from reciprocity, recognition, and incorporation ab initio (Hartman, Saidiya V. 1997. Scenes of Subjection: Terror, Slavery, and Self-Making in Nineteenth-Century America. New York: Oxford University Press.). By engaging the works of key Marxist feminist theorist Leopoldina Fortunati, I will demystify the ways in which these three homologies which non-Black women depend upon for the coherence of their complaint are parasitic on the flesh of Black women and men. 相似文献
190.
Scaling methods pioneered by Poole and Rosenthal (Am J Polit Sci 29(2):357–384, 1985) redefined how scholars think about and estimate the ideologies of representatives seated in the US Congress. Those methods also have been used to estimate citizens’ ideologies. Whereas studies evaluating Congress typically use a behavioral measure, roll call votes, to estimate where representatives stand on the left-right ideological spectrum, those of the public most often have relied on survey data of stated, rather than revealed, preferences. However, measures of individuals’ preferences and, accordingly, estimates of their ideal points, may differ in important ways based on how preferences are elicited. In this paper, we elicit the same individuals’ preferences on the same 10 issues using two different methods: standard survey responses measured on a Likert scale and a donation exercise wherein individuals are forced to divide $1.50 between interest groups with diametrically opposed policy preferences. Importantly, expressing extreme views is costless under the former, but not the latter, method. We find that the type of elicitation method used is a significant predictor of individuals’ ideal points, and that the elicitation effect is driven primarily by Democratic respondents. Under the donation method, the ideal points of Democrats in the aggregate shift left, particularly for those Democrats who are politically engaged. In contrast, wealthy Democrats’ ideal points shift to the right. We also document effects for Republicans and Independents and find that overall polarization is similar under both elicitation methods. We conclude with a discussion of our results, and the consequences and tradeoffs of each elicitation method. 相似文献