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Mitochondrial DNA (mtDNA) analysis of forensic samples typically is performed when the quantity and quality of DNA are insufficient for nuclear DNA analysis or when maternal relatives may be the only reference source. Many of the steps required in the analytical process are both lengthy and labor intensive. Therefore, improvements in the process that reduce labor without compromising the quality of the data are desirable. The current procedure requires purification of the amplicons by centrifugal filtration after PCR and prior to cycle sequencing. Because this method requires several manipulations to perform, alternate cleanup procedures were investigated. These include the use of 1) Qiagen QlAquick PCR Purification columns, 2) Concert Rapid PCR Purification columns, and 3) ExoSAP-IT reagent. When the yield of purified amplicons, quality of the sequence profile, and ease of assay were evaluated, the use of ExoSAP-IT reagent for post-amplification purification was chosen to replace the filtration method. 相似文献
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The purpose of this research was to examine gender and body mass, as factors linked to perceived experiences within the peer appearance culture. The sample included 215 girls and 200 boys who were either in 7th grade or 10th grade. Students provided self-reports on experiences in three domains: appearance culture among friends (appearance conversations and diet/muscle talk), peer evaluations (peer appearance pressure, appearance teasing, and vicarious peer teasing), and peer acceptance concerns (appearance-based acceptance, peer appearance comparison). The results indicated that although girls reported more appearance conversations, boys perceived more appearance pressure and teasing. Boys also admitted that they talked with friends about muscle building at a rate greater than girls talked about dieting. BMI showed distinct gender patterns. BMI was a key attribute that unified the experiences within the appearance culture for overweight girls. Among the boys, BMI was associated with differentiated experiences for underweight and overweight participants.Associate Professor in Educational Psychology at the University of Washington. She is a developmental psychologist specializing in the contributions of peers to body image and social-emotional well-being during adolescence. Research interests include body image during adolescence and gender differences.Doctoral student at the University of Washington in Human Development and Cognition. Her research focuses on the social-emotional development of adolescents, academic and appearance social comparisons, and issues related to gender and science. Research interests include body image during adolescence, gender differences, social comparison, and academic competence. 相似文献
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In this article we examine the impact of devolution on electoralpolitics in Scotland and Wales. After reviewing the electoralhistory of the two territories, we set out the result for the1999 and 2003 devolved elections, noting the substantial differencesbetween voting patterns in these elections from those for theUK parliament. We then go on to consider the main reasons whyvoting patterns differ across the two types of poll. The paperconcludes by summarizing the main findings and then consideringboth the implications of the findings for future devolved electionsand the potential contribution of the study of such electionsto broader theories of voting behavior. 相似文献
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Abstract: An industry-specific plan for the heavy engineering industry was introduced by the federal Labor government in 1986. It is an important subject for several reasons. Heavy engineering is a vital industry but receives little publicity. The manner of the plan's introduction is representative of Labor's priorities in its first period of office. The plan's character was exemplary in its forward-looking emphasis on reconstruction. Finally, the adverse bureaucratic environment in which the plan operated provides salutary lessons for cost-efficient and workable industry policy in the future. 相似文献
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