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81.
This study examines the amplification success rate of mitochondrial DNA from human head hair with respect to their potential for forensic application. Mitochondrial DNA was isolated using a Chelex-based extraction method and amplified using the LINEAR ARRAY duplex PCR system. The particular focus of this study was to characterize the morphological features of human head hair in order to further the understanding of the factors that influence amplification success rate in hair tissue using the LINEAR ARRAY duplex PCR system. 2554 head hairs from 132 individuals representing four population groups were amplified. The hair samples were characterized as follows: 1251 were identified microscopically as telogen hairs and 1303 were classified as hairs without roots (removed before extraction). Amplification success was assessed as a function of several independent variables: morphological characteristics; telogen root versus no root; donor age; scalp origin; use of cosmetic hair treatments; and race of the donor. The results show that a positive correlation exists between amplification success and the presence of a telogen root. Combining the amplification success with either the original or optimized protocol, telogen hairs result in an overall success rate of 77.5% compared with 65% for hairs with no roots. Controlling for telogen hairs, the findings indicate that the overall success rate is independent of cosmetic hair treatments; medulla structure; shaft length, diameter, and volume; and scalp origin. Conversely, the age of the donor, the race of the donor, and hair pigmentation all contribute to a variation in amplification success rate. 相似文献
82.
Katja Björklund Ph.D. Helinä Häkkänen‐Nyholm Ph.D. Lorraine Sheridan Ph.D. Karl Roberts Ph.D. Asko Tolvanen Ph.D. 《Journal of forensic sciences》2010,55(4):1008-1014
Abstract: Stalking behavior and victim–stalker relationship are often the principal known factors in a stalking case. Thus, they are of great importance when trying to identify factors contributing to stalking duration. The present study aims to identify distinct subgroups of stalking victims based on measures of behavioral stalking dimensions. These victim subgroups, stalking dimensions, and victim–stalker relationship are examined in relation to stalking duration. Using a sample of 137 university students, latent profile analysis (LPA) revealed five distinct victim subgroups based on stalker behavior dimensions: surveillance, low‐profile, social lurker, wide scope, and baseline stalkers. The subgroups were significantly related to stalking duration and explained a considerable amount of the variance along with the stalking dimensions and victim–stalker relationship. Connections to stalking literature and utility of person‐orientated methods in stalking research are discussed. 相似文献
83.
Helen Kemmitt Michael Dizon Karen Roberts Bianca Chouls 《Computer Law & Security Report》2010,26(6):655-658
This is the latest edition of Baker &; McKenzie's column on developments in EU law relating to IP, IT and telecommunications. This article summarises recent developments that are considered important for practitioners, students and academics in a wide range of information technology, e-commerce, telecommunications and intellectual property areas. It cannot be exhaustive but intends to address the important points. This is a hard copy reference guide, but links to outside web sites are included where possible. No responsibility is assumed for the accuracy of information contained in these links. 相似文献
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Forensic arthropod succession patterns are known to vary between regions. However, the northern habitats of the globe have been largely left unstudied. Three pig carcasses were studied outdoors in Whitehorse, Yukon Territory. Adult and immature insects were collected for identification and comparison. The dominant Diptera and Coleoptera species at all carcasses were Protophormia terraneovae (R‐D) (Fam: Calliphoridae) and Thanatophilus lapponicus (Herbst) (Fam: Silphidae), respectively. Rate of decomposition, patterns of Diptera and Coleoptera succession, and species dominance were shown to differ from previous studies in temperate regions, particularly as P. terraenovae showed complete dominance among blowfly species. Rate of decomposition through the first four stages was generally slow, and the last stage of decomposition was not observed at any carcass due to time constraints. It is concluded that biogeoclimatic range has a significant effect on insect presence and rate of decomposition, making it an important factor to consider when calculating a postmortem interval. 相似文献
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Shani R. Roberts Rhonda K. Lewis Chakema Carmack 《Journal of prevention & intervention in the community》2013,41(4):310-319
Over the past few decades researchers have begun to examine the importance of understanding positive youth development and the many contexts in which youth find themselves. The social contexts in which adolescent development occurs are varied and complex, particularly the development among African American youth. African American youth are faced with a number of challenges including living in single-parent homes, high teen pregnancy rates, and poor neighborhoods, yet many of these youth continue to thrive. The purpose of this study was to examine the relationship between family structure (single-parenting) and adolescent outcomes such as educational aspirations and sexual activity among African American adolescent youth aged 12–17. Approximately 462 African American youth were surveyed. A number of positive results emerged; for instance, there was a negative correlation between family structure and educational aspirations. The number of parents in the home did not interfere with youth wanting to complete high school and go on to college (r = ? .218, r² = .04, p < .05). The results also showed that as educational aspirations increased, the number of sexual partners decreased (r = ? .141, meaning that the more adolescents reported a desire to complete high school, they were less likely to report having sexual intercourse. These positive results should be promoted among African American youth so that those faced with these challenges will note that others have overcome and accomplished their goals. In this population educational aspirations were important. Limitations and future research are discussed. 相似文献
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Jamilia R. Sly Rhonda K. Lewis Shani R. Roberts Shoshana Wernick Felecia A. Lee Chris M. Kirk 《Journal of prevention & intervention in the community》2013,41(4):333-345
The purpose of this article was to assess the overall health behaviors of African American emerging adults who live in a Midwestern city. Two hundred participants, ages 18–25, completed a 129-item survey. Results indicate that African American emerging adults are engaged in relatively healthy behaviors (i.e., physical activity, low substance use). The results also showed that within the emerging adult developmental period, there are differences in behavior for those who are in the younger (18–20) versus those that are older (21–25) in the developmental period. Limitations, future research, and implications for practice will also be discussed. 相似文献
90.
Helene Helboe Pedersen 《West European politics》2013,36(4):896-910
What parties want – policy, office or votes – affects how they represent their voters, make strategic decisions and respond to external changes in society. What parties strive to accomplish is crucially important for what they do. Moreover, our knowledge of what parties want affects what we expect them to do. For instance, coalition theory assumes that parties have homogeneous goals, and hence are equally likely to join coalitions given the same circumstances. However, this article investigates this basic assumption of party goal homogeneity and finds that party goals do indeed diverge. The article demonstrates that party goals are influenced by party-specific factors such as party size, policy position and intra-party politics. It therefore suggests, further, that intra-party politics should be included more systematically in future studies of party behaviour. 相似文献