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461.
Peter M. Vallone Carolyn R. Hill Kristen E. Lewis Toni M. Diegoli Michael D. Coble John M. Butler 《Forensic Science International: Genetics Supplement Series》2009,2(1):29-30
Ongoing work at the U.S. National Institute of Standards and Technology has focused on the characterization of 26 autosomal STR loci for human identity testing. These 26 loci are in addition to the existing 13 U.S. core loci and those found in PowerPlex16 and Identifiler commercial STR typing kits. The amplification of the 26 loci has been optimized for degraded extracts in unique miniplex panels and also for reference samples as a single reaction 26plex assay. A study has been performed comparing genotypes obtained with the 26plex primers to those with miniplex panels for allele drop out and concordance. The forensic utility of the 26plex assay was evaluated for situations where additional loci are beneficial. The utility of this large multiplex was also tested in a case involving DNA extracted from degraded bone samples. The 26plex can serve as a low-cost assay (compared to commercially available kits) useful for both sorting comingled remains and providing additional markers for increased statistical support for samples that require “non-trio” family references for human identification. 相似文献
462.
Active research on a wide range of political contexts centers on ethnicity's role in collective action. Many theories posit that information flows more easily in ethnically homogeneous areas, facilitating collective action, because social networks among coethnics are denser. Although this characterization is ubiquitous, little empirical work assesses it. Through a novel field experiment in a matched pair of villages in rural Uganda, this article directly examines word‐of‐mouth information spread and its relationship to ethnic diversity and networks. As expected, information spread more widely in the homogeneous village. However, unexpectedly, the more diverse village's network is significantly denser. Using unusually detailed network data, we offer an explanation for why network density may hamper information dissemination in heterogeneous areas, showing why even slight hesitation to share information with people from other groups can have large aggregate effects. 相似文献
463.
The primary aim of this study was to explore motivations underpinning aggression among men detained within conditions of high security. Thirty men residing at a high secure psychiatric hospital completed self-report measures, including the Aggression Motivation Questionnaire, Revised EXPAGG and Barratt Impulsiveness Scale-IIr. The Historical items of the Historical, Clinical and Risk-Management (HCR-20) and the Psychopathy Checklist-Screening Version were rated. A subsample of participants agreed to complete a functional assessment on an aggressive incident that had occurred during their placement (n = 9). Increased psychopathy and impulsivity, and the presence of historical risk items were predicted to associate with higher levels of both aggression motivation and beliefs supportive of aggression. Young age at first violent incident and personality disorder related positively to aggression motivation. Thematic analysis conducted on the functional assessments identified social recognition, emotion regulation, communication and protection as functions underpinning aggression. Results are discussed with regards to their implication for violence treatment and assessment, with a focus on motivation recommended. 相似文献
464.
465.
Why do local officials in an authoritarian bureaucracy experiment with policy, even when directed not to do so by central‐level officials? This study suggests that policy experimentation in this institutional environment can best be understood as an interaction between the structure in which local officials are embedded and individual‐level personality attributes. Leveraging a new data set from a series of original surveys with local policy makers in mainland China, conducted between 2016 and 2018, we discern three baseline personality types: authoritarian, consultative, and entrepreneurial. We thereafter examine the individual‐level characteristics of local officials who will innovate irrespective of a centralization of bureaucratic power and interests, as currently experienced under Chinese President Xi Jinping. We find that local policy makers engage in policy innovation when they are more focused on resolving governance problems and that increased risk reduces but does not eliminate their willingness to innovate. Based on these findings, we contend that future studies of policy innovation should use an evolutionary framework to examine the interaction between preferences and selection pressures. 相似文献
466.
Lewis Zirogiannis 《Family Court Review》2001,39(3):334-343
Expert testimony on unsubstantiated social science syndromes such as the Parental Alienation Syndrome (PAS) has been increasingly admitted in courtrooms across the United States. This is a problem because a trier of fact is making a determination based on theories that are inaccurate or incorrect. To remedy this, the standards of admissibility for expert testimony must be heightened. The broad discretion given to trial judges in determining admissibility should be reevaluated and a new rule of evidence for social science testimony should be adopted. 相似文献
467.
468.
利用从猪传染性胃肠炎病毒(TGEV)Miler株(M5C)克隆建立的一株重组杆状病毒(R2-2)表达的重组TGEV钉状糖蛋白(S),建立了一种阻断酶联免疫吸附试验(ELISA)来检测猪群抗TGEV抗体。试验表明,用重组病毒R2-2接种sf9细胞(spodopterafrugiperda)所表达的重组蛋白量在接种后第72h达到最高值;该重组蛋白能与抗TGEVS蛋白A位点的单克隆抗体特异性结合。用阻断ELISA检测68份来自无TGEV感染或TGEV(Purduel5)免疫的仔猪或母猪血清,结果与TGEV蚀斑减数试验完全相符,灵敏度和特异性均为100%。同时检测来自TGEV试验免疫猪、美国部分地区猪群、我国进口猪以及我国国内猪群血清627份,阳性检出率分别为82.61%、61.62%、58.33%和29.10%;用中和试验(微量中和试验或病毒蚀斑减数试验)检测的TGE血清抗体阳性率分别为80.87%、59.60%、56.11%和30.60%,两种方法对抗TGEV抗体的检出率没有显著差异。 相似文献
469.
Catherine M. Cupples M.S. ; Jarrod R. Champagne M.S. ; Kristen E. Lewis M.S. ; Tracey Dawson Cruz Ph.D. 《Journal of forensic sciences》2009,54(1):103-107
Abstract: Screening methods capable of identifying DNA samples that will not yield short tandem repeat (STR) profiles are desired. In the past, quantitation methods have not been sensitive enough for this purpose. In this study, low level DNA samples were used to assess whether Quantifiler™ has a minimum quantitation value below which STR profiles would consistently fail to be detected. Buccal swabs were obtained and the DNA extracted, quantified, and serially diluted to concentrations ranging from 0.002 to 0.250 ng/μL. Samples were analyzed once with Quantifiler™, followed by Profiler Plus™ amplification and capillary electrophoresis analysis. An absolute minimum value below which STR results were unobtainable could not be defined. From the 96 low level samples tested, STR loci (including one full profile) were successfully amplified and detected from 27% of the samples "undetected" by Quantifiler™. However, no STR alleles were detected in 73% of these "undetected" samples, indicating that Quantifiler™ data may be useful for predicting STR typing success. 相似文献
470.
Lewis Husain 《当代中国》2016,25(99):438-452
Sub-national governments in China have substantial responsibility for policy development as well as for direct implementation of circumscribed policy options set out by higher levels of government, and much policy discourse emphasizes the importance of sub-national flexibility and creativity in policy implementation. Discourses of government innovation aim to encourage local initiative in policy formulation and solving of systemically-important policy problems, and policy experimentation/innovation are increasingly credited as important elements of the Chinese government toolbox in managing reform. Recent studies have tended to treat experimentation/innovation as systemic phenomena, and there are few analyses of how local governments respond to central ‘experimental’ policy frameworks and develop locally- or systemically-useful policy solutions. Given concerns around the capacity of local governments, this is highly relevant in understanding how locally-generated policy relates to systemic reform. The article presents a case study of a low tech and ‘second best’ reimbursement mechanism developed sub-nationally under the New Cooperative Medical Scheme, China’s rural health insurance framework, and its spread and incorporation into national policy. It argues for the importance of local government development of ‘appropriate’ policy mechanisms (jizhi) as underpinning central reforms and system adaptation. 相似文献