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61.
62.
Validation of a 16-locus fluorescent multiplex system   总被引:24,自引:0,他引:24  
STR multiplexes have been indispensable for the efficient genotyping of forensic samples. The PowerPlex 16 System contains the coreCODIS loci, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, CSF1PO, FGA, THOI, TPOX, vWA, the sex determinant locus, amelogenin, and two pentanucleotide STR loci, Penta D and Penta E. This multiplex satisfies the locus requirements for most national databases and is the most efficient currently available system due to its single PCR amplification. To provide the groundwork for judicial acceptance, including the publication of primer sequences, and to evaluate laboratory-to-laboratory variation, a developmental validation for casework on this commercially available system was performed in 24 laboratories and produced the following conclusions. Amplification was reliable on a variety of thermal cyclers and product could be analyzed on either an ABI PRISM 310 Genetic Analyzer or an ABI PRISM 377 DNA Sequencer. Genotyping using single source samples was consistent between 0.25 and 2 ng of input DNA template with a few laboratories obtaining complete genotypes at 0.0625 ng. However, heterozygote allele imbalance (<60% peak height balance) caused by stochastic effects was observed at a rate of 13% with 0.125 ng DNA and 22% at 0.0625 ng DNA. Mixture analyses were done using a total of 1 ng of DNA template. Most alleles were detected in mixtures of 4 to 1 and some minor alleles were detected in mixtures of 19 to 1. Optimum amplification cycle number was dependent on the sensitivity of the detection instrument used and could also be adjusted to accommodate larger amounts of DNA on solid supports such as FTA paper. Reaction conditions including volume, annealing temperature, and concentrations of primer, AmpliTaq Gold, and magnesium were shown to be optimal yet robust enough to withstand moderate variations without affecting genotype analysis. Environmental, matrix and standard source analyses revealed an ability to obtain complete genotypes in all sample types except those exposed to 80 degrees C for 12-48 days. Finally, comparison of genotype results from the PowerPlex 16 System with other commercially available systems on non-probative reference and forensic samples showed consistent results.  相似文献   
63.
This paper examines a number of demographic aspects in congressional districts and states that played important roles in a series of Congressional votes on environmental issues in 2000. These characteristics include urbanization or population density, education, income, race, and employment. Our findings are mixed. While we find some evidence (at least in Senate votes) that population density is a positive predictor of “pro-environment” votes, we also find that things commensurate with the Environmental Kuznets Curve such as income, education, and lifestyle also play an important role in environmental voting.  相似文献   
64.
大学推进科研成果转化对促进社会经济发展和提升大学创新能力具有重要作用。为推进科研成果转化,大学要营造良好的校园文化,为教师和学生开展科研活动及转化成果提供保证。奥克兰大学在此方面做了如下工作:在学生中提倡创业精神,鼓励学生成为企业家;把教师和研究人员作为提升大学创新能力的主体;构建有利于科研成果转化的政策环境;组建专门服务公司。  相似文献   
65.
Digby Anderson 《Society》2002,39(3):34-41
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67.
Relationship schemas are core elements of personality that guide interpersonal functioning. The aim of this study is to examine stability and change in relationship schemas across two developmental epochs—adolescence and young adulthood—in the stories that people tell about their interactions with others. Using the Core Conflictual Relationship Theme Method, relationship themes were coded from semistructured interviews conducted in adolescence and again at age 25. The sample consisted of 40 participants in a longitudinal study of adolescent and young adult psychological development. There was considerable stability in the frequency with which particular themes were expressed in the narratives of adolescents and young adults. Significant changes from adolescence to young adulthood included a decrease in the perception of others as rejecting and of the self as opposing others. Young adults saw themselves and others more positively, and used a broader repertoire of themes in their relationship narratives than they had as adolescents. The basic continuity and particular changes in relationship schemas found in this study are consistent with knowledge about the adolescent-to-young-adult transition derived from other empirical and clinical findings. Relationship schemas may be rich units of study for learning about the development of interpersonal functioning.  相似文献   
68.
Allen  Stuart D.  Bray  Jeremy  Seaks  Terry G. 《Public Choice》1997,92(1-2):27-39
Previous studies have used probit or logit models to analyze two states of monetary policy (tighter or looser). In this paper we employ multinominal logit to permit Federal Reserve monetary policy to assume one of three alternative states (tighter, looser, or no change) as a function of three independent economic variables (unemployment, real growth, and inflation) and the amount of experience of the Board of Governors. The results indicate that the Federal Reserve reacted differently under Burns, Miller and Volcker and between Volcker's two operating procedures in the formulation of monetary policy.  相似文献   
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70.
The purpose of the pilot study was to examine the interrelationship between social support, risk-level, and safety actions for 2 groups of suicidal adolescents (50 attempters and 50 ideators), who had presented for an acute assessment at an outpatient mental health service. A social support model was proposed in which it was thought that information related to patients' social support would impact upon the types of risk-level and safety actions made by clinicians. Data was collected from a total of 100 patient files, utilizing the acute assessment reports (e.g., reports assessing risk of self-harm). Findings show that groups differed significantly on indices of negative support severity, positive support, and risk-level. Limited support was found for the proposed social support model. Limitations and implications for future research are discussed.  相似文献   
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