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21.
The effect of various stain carriers on the quality and quantity of DNA extracted from dried bloodstains 总被引:1,自引:0,他引:1
Bloodstains were made with 200 microliters blood on each of 11 different common substrates to examine the effect of the stain carrier on the amount and quality of DNA recoverable. High-molecular-weight DNA was extracted from all samples after 2 days. The yield of DNA from each sample varied considerably, not only between the different stain carriers but also within a given category. With a DNA yield of up to 10 micrograms, paper, glass, nylon, wood, smooth leather and wool gave the best results, followed by blue denim and wallpaper (up to 6 micrograms), cotton fabric and carpeting (up to 4 micrograms) and suede (up to 2 micrograms). For several stain carriers the DNA-containing solution was contaminated by chemical substances, which in the case of the blue denim, suede, and carpet samples inhibited the digestion of the DNA with restriction enzymes and prevented DNA typing. The different textures of the stain carriers tested and (as for varying yields on the same carrier) the differing degree of loss of DNA during extraction and the physiological variation in the number of leukocytes in human blood are discussed as possible reasons for the wide range of variation in the amounts of DNA it was possible to extract. 相似文献
22.
Rebecca Emerson Stephen G. Hall Anna Zalewska-Mitura 《Economic Change and Restructuring》1997,30(2-3):75-90
With new technically advanced methods and computers at our disposal, the efficient market hypothesis is once again being debated. At the same time, we are witnessing an unprecedented growth in both existing and new financial markets. These new markets are often in economies which have just recently embraced free market economics; we term these stock markets infant markets. Such stock markets are obviously not efficient in allocating the supply of savings to productive capital. We do not test whether or not these infant markets are informationally efficient, but instead examine whether and how they are becoming more efficient. We propose modelling the excess returns of individual securities using a multi-factor model with time-varying coefficients and generalised auto-regressive conditional heteroskedastic (GARCH) errors. If the markets are becoming more informationally efficient or the agents are learning, we would expect this to manifest itself as the time-varying coefficients becoming more stable as time increases. We test our model using data on four Bulgarian shares. First, we estimate an AR(2) model and a GARCH-M(1,1) model for the shares. Then, we estimated our AR(2) model with time varying coefficients and GARCH type errors. We find varying levels of efficiency and varying speeds of movement towards efficiency within our sample of four shares. 相似文献
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The Tax Reform Act of 1986 rewrote the federal income tax code, bringing it closer to policy professionals' vision of what constitutes an equitable and efficient income tax. Research on tax compliance suggests the law might have affected taxpayer compliance in three ways: by reducing opportunities to overstate deductions, by changing perceptions of fairness, and by altering tax liabilities. Changes in taxpayer perceptions, attitudes, and noncompliance intentions were examined in three bodies of survey data, each containing pre-and post-reform data from independent samples of the same population. The results show an improved normative climate for taxpayer compliance and point to both the feasibility and the importance of examining the effects of substantive tax policies on taxpayer perceptions, attitudes, and behavioral intentions. 相似文献
26.
The formation of adequate mental health systems within prisons has accelerated as a result of successful class action lawsuits. Our recent national survey questioned all state correctional departments about the existence of standards in each system, compliance with such standards, prevalence of class action lawsuits involving the issue of providing adequate mental health services for inmates, issues related to consent decrees, available mental health resources within the correctional system, and the administrative structure of the mental health system. Our purpose was to identify those factors correlated with certified class action lawsuits involving issues related to mental health services. Twenty-one states were involved in such litigation. Only the presence of psychiatric hospitals operated by the department of corrections correlated with the presence of certified class action lawsuits involving mental health services. Prison systems larger than 15,000 inmates were at higher risk for such litigation. Smaller systems having psychiatric hospitals run by the state mental health agency appeared to be at less risk for such litigation. 相似文献
27.
W D Haglund D G Reichert D T Reay 《The American journal of forensic medicine and pathology》1990,11(1):35-43
The Green River Murder Investigation in King County, Washington, is currently the longest active serial murder investigation in U.S. history. During its course, over 26 separate scenes with from one to five victims each have been processed. The experience of the authors is presented in order to acquaint other agencies with techniques of outdoor scene processing that have evolved during recovery of remains from Green River and other skeletal cases. 相似文献
28.
Australian policy‐makers continue to rely on municipal amalgamation as the main engine of structural reform in local government, despite strong evidence that it diminishes participation and representation without improving service efficiency. Several promising, but neglected alternative models of structural reform have been developed, including ad hoc resource sharing models, Regional Organisations of Councils, virtual local government, and agency models. In an encouraging response to the recent policy of enforced council amalgamations in NSW, the Shires Association of NSW (2004) has recently proposed a ‘Joint Board model’ of local governance and invited comment on this model. This article takes up this challenge and seeks to place the Joint Board model in conceptual context and evaluate its characteristics and simulated cost savings. 相似文献
29.
Brian Rosebury 《Ratio juris》2003,16(1):37-55
This paper challenges recent influential arguments which would encourage legislators and courts to give weight to an assessment of the "evaluative judgements" expressed by the emotions which motivate crimes. While accepting the claim of Kahan and Nussbaum and others that emotions, other than moods, have intentional objects ("the cognitive conception"), and are not mere impulses which bypass cognition ("the mechanistic conception"), it suggests the following criticisms of their analysis. First, the concept of an emotional "evaluative judgement" tends to elide the distinction between (misleadingly named) "judgements" that are merely the sense of an emotion, and do not have the character of acts, and deliberative emotional judgements that do resemble acts and so properly fall within the corrective scope of the law. Second, intentional emotions are empowered by pre–intentional psychological resources which are less amenable than intentional states to the agent's conscious supervision: The traditional recognition of "infirmity" in mitigation of crimes uncharacteristic of the criminal's overall conduct towards others is justified by the unpredictable action of these pre–intentional elements and can survive the abandonment of the mechanistic conception of emotion. 相似文献
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