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91.
92.
High levels of non-authentic sequence data can be generated by traditional PCR-based methodologies when DNA is damaged, template numbers are small and/or the target amplification size too large. We therefore present an alternate methodology based on single primer extension (SPEX) amplification; that places no pre-defined size constraints on amplification and interacts with only one of the DNA strands at the target locus.  相似文献   
93.
Drug use histories were collected from 100 subjects recruited from the "dance scene" in and around Glasgow, Scotland. In addition, each subject donated a hair sample which was analyzed by gas chromatography/mass spectrometry (GC/MS) for amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MD MA) and 3,4-methylenedioxyethylamphetamine (MDEA). The hair samples were analyzed in two 6 cm segments or in full, ranging from 1.5 to 12 cm depending on the length of the hair. Approximately 10 mg of hair was ground to a fine powder before treatment with beta-glucuronidase/aryl sulfatase. A solid-phase extraction procedure was carried out followed by derivatization with pentafluoropropionic anhydride (PFPA). All extracts were analyzed by gas chromatography/mass spectrometry (GC/MS). Of the 139 segments analyzed, 77 (52.5%) were positive for at least one of the five amphetamines. The drug concentrations found in the hair were compared with the self-reported drug histories. A concordance of greater than 50% was found between the self-report data and levels detected in hair. However, no correlation was found between the reported number of "ecstasy" tablets consumed and the drug levels detected in hair. An increase in the average drug levels measured was observed from low to high use (number of "ecstasy" tablets/month). A large number of false negatives and a low number of false positives were observed.  相似文献   
94.
We have investigated the susceptibility of degraded human hair shaft samples to contamination by exogenous sources of DNA, including blood, saliva, skin cells, and purified DNA. The results indicate that on the whole hair shafts are either largely resistant to penetration by contaminant DNA, or extremely easy to successfully decontaminate. This pertains to samples that are both morphologically and biochemically degraded. We suggest that this resistance to the incorporation of contaminant DNA relates to the hydrophobic and impermeable nature of the keratin structures forming the hair shaft. Therefore, hair samples represent an important and underestimated source of DNA in both forensic and ancient DNA studies.  相似文献   
95.
This study examines the relationships between adult attachment orientations and the ability to seek social support as factors in mediating behavior. Data were collected on non violent offenders (n = 57) and college students (n = 89). The results indicated the non-normative group of nonviolent offenders reported being more securely attached and having more satisfaction with their social supports than the normative group of college students. Fewer college students reported being securely attached than the nonviolent offenders but had a larger number of social supports. In the insecure categories, nonviolent offenders reported being more dismissively attached whereas college students reported being preoccupied in their attachment orientation. The study suggests that attachment and social-support-seeking behaviors across different populations may be potential factors in designing counseling services that are used for risk classification and needs assessment.  相似文献   
96.
97.
Civic engagement and collaborative public management are concepts that are defined broadly, making theoretical explication challenging and practical application of empirical research difficult. In this article, the authors adopt definitions of civic engagement and collaborative public management that are centered on the citizen and the potential for active citizenship. Following a historical review of civic engagement in the United States, a conceptual model of five approaches to civic engagement is offered. Citizen-centered collaborative public management is enhanced through these approaches. The authors suggest the need for further empirical research on collaborative public management that is grounded in citizenship action.  相似文献   
98.
This study focuses on the role of family experience in adolescents' conception of the self in the context of friendship and dating relationships. Three issues are addressed: the extent of sex differences in adolescents' friendship and dating identity, how links between family experience and friendship and dating identity might differ for males and females, and whether mothers and fathers play distinctive roles in such development. A sample of Caucasian two-parent families, each including an adolescent who was a high school senior, was observed in a family interaction task designed to elicit the expression and coordination of a variety of points of view. Each adolescent was also given an interview assessing exploration and commitment in friendship and dating identity. Only one sex difference was found in identity, with females more committed in their conceptions of dating relationships than males. The key finding of the study concerns the distinctive patterns of family interaction associated with friendship and dating identity. For females, separateness in family interaction was related to their friendship identity exploration, whereas for males, the links between family interaction and exploration all involved connectedness. The different contingencies may reflect the interplay between different societal patterns of support and restriction of males' and females' exploration.This work was supported by grants from the National Institute of Child Health and Human Development (HD-92819 and HD-17983) and the Hogg Foundation for Mental Health and from the University Research Institute and the Institute of Human Development and Family Studies of the University of Texas at Austin.Received her Ph.D. in child psychology from the University of Minnesota. Research interests include the role of family and peer relationships in the development of individual and relational competence, and the interface of family, peer, and school contexts in the development of children and adolescents.Received his Ph.D. in child psychology from the University of Minnesota. Research interests include the role of the family in adolescent personality development and identity formation, career development, and adoptive family relationships.  相似文献   
99.
100.
Racial/ethnic differences in the prevalence and correlates of self-reported spousal violence in a community sample of Anglo, Black, and Mexican American adults are examined. Females, the formerly married, and Black females in particular (up to 60% of formerly married) were most likely to report both being beaten by and beating a spouse. Multivariate analyses controlling for demographic variables, financial stress, social desirability, sex role traditionalism and drinking quantity (and spouse's drinking among the currently married) did not eliminate the greater likelihood of reports of both beating and being beaten among married Black females. There was little consistent evidence to suggest greater violence propensity among Mexican American than Anglo respondents. The findings raise questions about simplistic socioeconomic status or financial stress explanations of observed racial/ethnic differences in spousal violence. Further, curvilinear effects of alcohol quantity and spouse drinking upon reported violence question simple disinhibition arguments and suggest the need for data regarding couple dynamics.  相似文献   
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