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931.
An original test-system for the preliminary quantitative and qualitative evaluation of isolated DNA is proposed by the polymerase chain reaction in real time (PCR-RT) based on the TaqMan technology. This test-system permits to simultaneously measure the amount of DNA in the sample, identify the genetic gender, and detect PCR inhibitors. The method has been approbated in the practical work of forensic medical experts.  相似文献   
932.
This study investigated the value of antemortem (AM) and postmortem (PM) radiographs of the claviculae and C3-T4 vertebrae to identify skeletons of missing U.S. soldiers from past military operations. In total, 12 field-recovered skeletons and AM chest radiographs of 1460 individuals were used. For each skeleton, examiners analyzed an array of AM chest radiographs (up to 1000 individuals) and attempted to identify the correct PM/AM radiographic match. When examiners were able to compare all images within a single test, only true-positive identifications were made. When AM radiographs were presented one-at-a-time, in sequential order, and without examiners having knowledge of array size, erroneous identifications resulted but they were almost exclusively made by untrained examiners (accuracy = 35% vs. 90% for trained examiners). This study demonstrates the value of chest radiographs for the identification of disarticulated and even eroded skeletons, but only when methods are wielded by trained examiners.  相似文献   
933.
The successful identification of human skeletal remains relies on proven diagnostic techniques for sex determination. This research utilized 608 individuals from South Africa (420 men, 188 women) to conduct a blind nonmetric determination of sex from three features of the distal humerus: olecranon fossa shape, angle of the medial epicondyle, and trochlear extension. A scoring system between males and females was implemented, and the aggregate score of the three features determined the estimated sex of the skeletal element in question. With all features combined, black and white South Africans were categorized successfully as either male or female 75.5% (77% accuracy rate for females, 74% accuracy rate for males). This classification rate is lower than what was found in previous studies, but suggests that characteristics of the distal humerus are still quite valuable when estimating skeletal sex. More research is needed to assess reasons for the differential expression of these traits in different populations and to determine whether the method is nonpopulation specific.  相似文献   
934.
935.
Self-control theory (Gottfredson and Hirschi 1990) argues that individuals with similar attributes tend to ‘end up together’ (i.e., homophily) because of the tendency to select friends based on self-control. Studies documenting homophily in peer groups interpret the correlation between self-control, peer delinquency, and self-reported delinquency as evidence that self-control is an influential factor in friendship formation. However, past studies are limited because they do not directly test the hypothesis that self-control influences friendship selection, nor do they account for other mechanisms that may influence decisions. As a result, it is unclear whether the correlation between individual and peer behavior is the result of selection based on self-control or alternative mechanisms. To address this gap in the literature this study employs exponential random graph modeling to test hypotheses derived from self-control theory using approximately 63,000 respondents from 59 schools from the National Longitudinal Survey of Adolescent Health (Add Health). In contrast to the predictions made by Gottfredson and Hirschi (1990), and the conclusions drawn from prior research, there is little evidence that self-control influences friendship selection. The findings are embedded in past work on the relationship between self-control and peer relationships, and implications for future research are discussed.  相似文献   
936.
What should be done to advance the study of public administration? A strong argument is advanced by outgoing PAR managing editor Jos C. N. Raadschelders that the field benefits significantly from greater attention to ontology and epistemology. To be sure, empirical, evidence‐based research has its place, but its basis and the meaning of findings seldom are questioned. Why? Many public administration scholars seek “scientificness” through a disciplinary type of methodology. However, working within an inherently interdisciplinary field, public administration scholars cannot reduce the complex, wicked problems of society and government to mere empirical measurement. The author lays out five critical challenges confronting today’s public administration—both its study and research—requiring the field’s urgent attention in order to meet the comprehensive and rapidly expanding needs of specialists and generalists, practitioners and academicians, as well as the general public.  相似文献   
937.
938.
This article considers a referendum which was held in the Republic of Ireland in 2004 involving a proposal to qualify the existing universal constitutional entitlement to birthright citizenship. Existing analysis of this referendum reflects dominant trends in citizenship scholarship. It does so by framing the issue in terms of two opposing perspectives – one particularistic (exclusive) and one universalistic (inclusive) – and positing the question of the ‘politics’ of citizenship as a trade-off between these diverging models. This article argues, however, that Rob (R.B.J.) Walker's notion of the constituent subject of (sovereign) politics challenges this dualistic framework as the necessary starting point for discussions about citizenship. It does so by problematizing the premise upon which it is based which is the taken-for-granted autonomous existence of persons (individuals) who are understood to be connected to, but ultimately separate from, ‘the state.’ This article concludes with reflections on what an alternative framework for exploring citizenship (based specifically on a historicization of subjectivity in relation to sovereignty) might look like. It suggests that this provides us with a different starting point to the prevalent form of a timeless dialectic of inclusion and exclusion, particularism and universalism, polis and cosmopolis currently determined by the boundaries of the Irish state.  相似文献   
939.
Claims to human rights protection made by displaced persons are displaced from the universe of humanity and rendered ineffective by the geopolitical character of modern international human rights law, in favour of the protection of citizens' rights claims. In response, there is increasing interest in leveraging respect for and protection of the rights of displaced persons through extension of the rights enjoyed and supposedly borne by emplaced citizens. However, it is a mistake to assume that humans as citizens bear human rights or that the freedoms that they may be able to extend beyond state boundaries are universalisable. The extension of the right to citizenship functions to displace questions of human rights themselves. The question of the human in rights is in fact always displaced, as long as the human subject is acted upon as if it could possess rights. In paying attention to the critical perspectives with which displaced persons confront the citizen, she or he may come to appreciate the fact that the universality of human rights is served where one does not claim to have rights but, rather, actively engages, without limits, with others in the struggle for rights and their respect.  相似文献   
940.
Adolescents’ friendships with other-sex peers serve important developmental functions, but they may also facilitate engagement in problem behavior. This study examines the unique contributions of other-sex friendships and friends’ behavior to alcohol use, smoking, and initiation of sexual intercourse among late adolescent girls and boys. A total of 320 adolescents (53% girls; 33% racial/ethnic minorities) provided sociometric nominations of friendships annually in grades 10–12. Friendship networks were derived using social network analysis in each grade. Adolescents and their friends also reported on their alcohol use, smoking, and sexual debut at each assessment. After controlling for demographics, previous problem behavior, and friends’ behavior, other-sex friendships in 10th grade were associated with initiation of smoking among girls over the following year, and other-sex friendships in 11th grade were linked with lower levels of subsequent alcohol use among boys. Additionally, friends’ smoking and sexual experience in 10th grade predicted the same behaviors for all adolescents over the following year. Other-sex friendships thus appear to serve as a risk context for adolescent girls’ smoking and a protective context for adolescent boys’ drinking. Promoting mixed-gender activities and friendships among older high school students may be helpful in reducing males’ alcohol use, but may need to incorporate additional components to prevent increases in females’ smoking.  相似文献   
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