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Johnson MH 《Journal of law and medicine》2002,9(4):399-413
How a society regulates Assisted Reproduction Technologies (ART) depends on cultural context. The challenge for the regulatory regime is to balance protection for patients and society with freedom for medico-scientific creativity. Neither an exclusively market-regulated nor a peer-regulated approach is realistic politically, or desirable socially, ethically and legally. Legitimate social issues that go beyond the exclusive expertise of doctors and scientists or market choice by patients need to be accommodated within the regulatory regime. Within this context, four key issues are discussed: the lack of a shared social ethic that helps the needs of the community to be balanced against those of its individual members; the negative impact of intrusive external regulation on scientists and doctors; the requirement for doctors and scientists to review their professional structures reflectively and critically if they are to be entrusted with peer-regulation; and the desirability of constructive dialogue between regulators and regulated rather than the use of coercion and criminal sanctions. 相似文献
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One of the most important longstanding problems in the field of forensic medicine is the determination of the time of death upon the discovery of a possible homicide victim. With a majority of homicide victims discovered within the first 48h, it is critically important to be able to determine time of death quickly, and with accuracy and precision. Current methods of determining postmortem interval (PMI) vary, but none can provide better than an 8-h window time estimate. In this paper, the potential application of single-cell gel electrophoresis (SCGE), also known as the comet assay, to evaluate postmortem cell death processes, specifically nuclear DNA fragmentation, is assessed. Upon the death of an organism, internal nucleases contained within the cells should cause chromosomal DNA to degrade into increasingly smaller fragments over time, and if these fragments can be isolated and visualized, the fragmentation should prove to be measurable and quantifiable. An original study providing proof of the concept of postmortem DNA fragmentation between early and late time periods was conducted using human leukocytes. With an established trend seen in the leukocyte results, this study was then expanded using a porcine animal model, over a longer time period, with more frequent time-points evaluated. DNA degradation in all samples was revealed by SCGE and quantified by the use of DNA-specific quantitative stains, as measured by digital camera affixed to a microscope. The comet 'tail-moment' gave a measure of the proportion of fragmented to non-fragmented DNA, while the 'tail-length' provided the relative size of degraded DNA fragments. In both models, an increase in DNA fragmentation was found to correlate with an increased PMI from 0 to 56h postmortem, as evaluated by comet-tail-moment and by comet-tail-length, with tail-length providing the strongest statistical correlation, based upon regression analysis. The postmortem DNA fragmentation observed in this study, reveals a sequential, time-dependent process with the potential for use as a predictor of PMI in homicide cases. 相似文献
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The ultimatum game is a standard instrument for laboratory experimentalists.It has been replicated in a large number of environments andpoints to special considerations for fairness. Although it hasbeen popular in the experimental community, researchers havenot harnessed all the statistical power they should to evaluatethe dynamics at work in this type of a bargaining game. Thisresearch uses two planned treatments, the first involving asignaling condition concerning a subject's "type," and the seconda price effect built into the structure of the game. We findthat there are no significant main effects as a result of thesignaling condition of a subject's type, but that there arestrong effects as a result of the different payoff parameters.Using a variety of multivariate models we find important, nonobviousinteractions with the gender of the subjects. The lesson thatwe take away from this research is that experimentalists canlearn more from data collected in the tightly controlled laboratoryenvironment by using statistical techniques that complementtheir research designs. 相似文献
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Greenspoon SA Yeung SH Johnson KR Chu WK Rhee HN McGuckian AB Crouse CA Chiesl TN Barron AE Scherer JR Ban JD Mathies RA 《Journal of forensic sciences》2008,53(4):828-837
Miniaturization of capillary electrophoresis onto a microchip for forensic short tandem repeat analysis is the initial step in the process of producing a fully integrated and automated analysis system. A prototype of the Berkeley microfabricated capillary array electrophoresis device was installed at the Virginia Department of Forensic Science for testing. Instrument performance was verified by PowerPlex 16 System profiling of single source, sensitivity series, mixture, and casework samples. Mock sexual assault samples were successfully analyzed using the PowerPlex Y System. Resolution was assessed using the TH01, CSF1PO, TPOX, and Amelogenin loci and demonstrated to be comparable with commercial systems along with the instrument precision. Successful replacement of the Hjerten capillary coating method with a dynamic coating polymer was performed. The accurate and rapid typing of forensic samples demonstrates the successful technology transfer of this device into a practitioner laboratory and its potential for advancing high-throughput forensic typing. 相似文献
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This field study reports on a cross-site evaluation of dependency courts in communities receiving federal funding to implement the Greenbook initiative, a multisite demonstration for community improvement of coordinated responses to families victimized by domestic violence and child maltreatment. This article focuses on the dependency court, where child maltreatment cases are heard, specifically court participation in collaborative activities and court practice improvements. Findings indicate that perceptions of judicial leadership varied considerably by site. Cross-training appeared to increase over time, particularly with court staff. Collaborative efforts emerged across the Greenbook initiative with regard to the courts, and some innovative practices appeared within Greenbook sites, such as separate case plans for perpetrators and victims of violence in families, reducing the likelihood of controversial failure to protect charges. Results also highlight challenges inherent in changing court practices. Research and practice implications are discussed, focusing on relevance to other communities attempting to work collaboratively with the court system. 相似文献