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171.
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
172.
A method has been developed for the rapid extraction of cocaine and benzoylecgonine from post-mortem blood and urine samples. Solid phase columns containing C8 packing material gave clean, emulsion free extracts from body fluids. The total time for each extraction was approx. 10 min and the system has the capacity for the simultaneous extraction of up to 10 samples. Urine can be extracted directly, blood samples were sonicated before extraction to allow for their easy passage through the columns. The method gave excellent recoveries of cocaine (98-100%) from spiked samples at concentrations of between 50 ng/ml and 10 micrograms/ml. Analysis of the extracts was by high performance liquid chromatography (HPLC). 相似文献
173.
This paper describes a simplified approach to calculating the Bayesian likelihood ratio for the case where two DNA single locus profiles are to be compared. It explains how the calculation allows for band shift and also for the variation in precision with molecular weight. A simple basic theory section explains the principles of the analysis but more detailed explanations are given in an advanced theory section. Experiments on substantial data collections are described which demonstrate the robustness of the method. 相似文献
174.
A small experiment is described which uses databases of Afro-Caribbeans and Caucasians to establish the quality of information that might be given to an investigator about the ethnic group of the donor of an unknown crime stain. The results show that the technique can provide qualified indications, but categoric conclusions are not, in general, feasible. An appraisal is given of the technique within the operational context. 相似文献
175.
Dorothy L. Espelage Kathleen C. Basile Ruth W. Leemis Tracy N. Hipp Jordan P. Davis 《Journal of youth and adolescence》2018,47(9):1880-1893
The Bully-Sexual Violence Pathway theory has indicated that bullying perpetration predicts sexual violence perpetration among males and females over time in middle school, and that homophobic name-calling perpetration moderates that association among males. In this study, the Bully-Sexual Violence Pathway theory was tested across early to late adolescence. Participants included 3549 students from four Midwestern middle schools and six high schools. Surveys were administered across six time points from Spring 2008 to Spring 2013. At baseline, the sample was 32.2% White, 46.2% African American, 5.4% Hispanic, and 10.2% other. The sample was 50.2% female. The findings reveal that late middle school homophobic name-calling perpetration increased the odds of perpetrating sexual violence in high school among early middle school bullying male and female perpetrators, while homophobic name-calling victimization decreased the odds of high school sexual violence perpetration among females. The prevention of bullying and homophobic name-calling in middle school may prevent later sexual violence perpetration. 相似文献
176.
Andre M. N. Renzaho Joseph Kihika Kamara Brian Stout Gilbert Kamanga 《Journal of Human Rights》2018,17(3):303-321
Child abuse and neglect are complex and polarizing issues in many low and middle income countries. We explore them through a situation analysis of child rights and protection in Uganda. A qualitative study, incorporating 10 focus group discussions (FGDs; N = 113) and 20 individual interviews was undertaken in Kampala, Uganda. Emerging themes were grouped into family and community-level factors; legal framework, structure and continuum of services, and human and financial resources. Violation of child rights was characterized by physical, emotional, and sexual abuse and exploitation; child neglect, homelessness, and child labor; dysfunctional families and abject poverty; and poor accommodation conditions; school drop-out due to economic hardship; early pregnancy, and social exclusion. Legal and regulatory factors included traditional harmful practices (including child sacrifice and witchcraft practices); forced marriage; and the perceived lack of the government's commitment to child protection. Without a strong legislation that protects children against abuse, promotes confidential reporting systems, and tackles domestic violence, children will still remain prone to various forms of abuses and exploitation. 相似文献
177.
Marcia M. Croft Maria I. Marshall Martins Odendo Christine Ndinya Naman N. Ondego Pamela Obura 《发展研究杂志》2018,54(4):758-775
Indigenous vegetables play an important role in Kenyan food security, but production is limited by poor seed quality. Traditionally, seeds have been traded through informal networks, but a new formal seed sector is emerging. This study assessed the relative potential for formal or informal seed systems to meet the need for high-quality indigenous vegetable seed. By evaluating determinants of farmers’ seed purchasing behaviour, we conclude that informal seed systems have greater potential to meet this need and should be strengthened. This study suggests that policy-makers should use context-specific data to guide decisions on seed policy. 相似文献
178.
Correlates of Childhood vs. Adolescence Internalizing Symptomatology from Infancy to Young Adulthood
John D. Haltigan Glenn I. Roisman Elizabeth Cauffman Cathryn Booth-LaForce 《Journal of youth and adolescence》2017,46(1):197-212
In light of its associations with child and adolescent health and well-being, there remains a need to better understand the etiological underpinnings and developmental course of internalizing symptomatology in children and adolescents. This study leveraged intensive longitudinal data (N?=?959; 49.6?% females) to test the hypothesis that internalizing symptoms in childhood may be driven more strongly by family experiences whereas internalizing symptoms in adolescence may derive more uniquely from familial loading for affective disorders (i.e., maternal depression). We evaluated the relative contributions of (a) family experiences (b) maternal depression, and (c) peer influences in testing this hypothesis. The results indicated that family predictors were more strongly correlated with childhood (relative to adolescent) internalizing symptoms. In contrast to previous findings, maternal depression also exhibited stronger associations with childhood internalizing symptoms. Although often overlooked in theories concerning potential differential origins of childhood vs. adolescent internalizing symptomatology, peer experiences explained unique variation in both childhood and adolescent internalizing problems. 相似文献
179.
No Need to Watch: How the Effects of Partisan Media Can Spread via Interpersonal Discussions 下载免费PDF全文
James N. Druckman Matthew S. Levendusky Audrey McLain 《American journal of political science》2018,62(1):99-112
To what extent do partisan media sources shape public opinion? On its face, it would appear that the impact of partisan media is limited, given that it attracts a relatively small audience. We argue, however, that its influence may extend beyond its direct audience via a two‐step communication flow. Specifically, those who watch and are impacted by partisan media outlets talk to and persuade others who did not watch. We present experimental results that demonstrate this process. We therefore show that previous studies may have significantly underestimated the effect of these outlets. We also illustrate that how the two‐step communication flow works is contingent upon the precise composition of the discussion group (e.g., is it consistent of all fellow partisans or a mix of partisans?). We conclude by highlighting what our results imply about the study of media, preference formation, and partisan polarization. 相似文献
180.
Previous studies have indicated homophily in depressive symptoms among adolescent friends, resulting from both peer selection
and socialization processes. However, developmental differences and the role of school transitions in these processes have
not been elucidated. A sample of 367 (51% female) adolescents was followed from 6th to 11th grade to investigate prospective
relationships between adolescents’ and their friends’ depressive symptoms in middle school and in high school. Results revealed
that students selected friends with similar levels of depressive symptoms after each school transition. Additionally, friends
appeared to socialize adolescents to become more similar in depressive affect in late middle school years. These findings
suggest normative selection effects after school transitions, followed by socialization effects in middle school, but not
high school. 相似文献