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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
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The extent to which local life circumstances influence criminal activity has been the focus of much theoretical debate. Although empirical research has been initiated, it remains limited. Herein, we use data on 524 serious offenders from the California Youth Authority for a seven‐year post‐parole period to examine the relationship between changes in local life circumstances and criminal activity. We extend previous research by employing a statistical model that accounts for the joint distribution of violent and nonviolent crime during the late teens and twenties in order to present information on patterns of criminal activity during a newly recognized developmental period of the life course, “emerging adulthood.” 相似文献
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On the basis of the uncertainty management model, we argue here that when people are uncertain about an organization's trustworthiness, they may resolve the question how they should react toward the organization by relying on their perceptions of the organization's procedures. As a consequence, we predicted that the reactions of parents whose child was in a day care center would be strongly influenced by their perceptions of the procedures used by the organization that was responsible for their children's day care when the parents would be uncertain about the organization's trustworthiness. However, when parents would be certain that the organization could be trusted they would be less in need of procedural information, yielding less strong effects of perceived procedure on parents' reactions. The findings of a survey study corroborate this line of reasoning. In the discussion it is argued that these findings suggest that people especially rely on their perceptions of procedures when they are uncertain about important aspects of their lives, such as the trustworthiness of organizations that are responsible for their children's day care. 相似文献
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In this paper we examine one of the areas where there is a marked difference between Civil and Common contract law, that of the enforcement of liquidated damages and more particularly of penalty clauses. Common law judges are quite reluctant to enforce liquidated damages, especially if they believe that they include penalty clauses which are not enforceable. On the contrary, in almost all European contract laws liquidated damages are readily enforced, as are penalty clauses when they are not manifestly excessive. Although most law and economics scholars have criticized Common law courts for the non-enforcement of penalty clauses, there is a sizable minority of scholars who have defended the Common law “non-enforcement” policy on the ground that penalty clauses are inefficient because they hinder efficient breach. However, and despite the merits of the arguments advanced by advocates of the non-enforcement of penalty clauses, we believe that Common law’s rejection of penalty clauses is inefficient. We further show that the Civil law solution to the problem is not only comparatively more efficient, but that it can also appease the worries of those scholars who are afraid that efficient breaches will be deterred. The solution that Civil law systems give to the problem manages to enforce the parties’ wishes and to avoid deterring efficient breaches. However, we point out that in order for the Civil law systems to take advantage of this superiority, the interpretation of their Civil Codes should be guided by economic analysis and the respect to the wishes of the contracting parties. 相似文献
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D J WILLIAMS WILLIAM B. STREAN ENRIQUE GARCIA BENGOECHEA 《Juvenile & family court journal》2002,53(2):31-41
This article discusses relevant literature on the potential benefits of sport, recreation, and leisure, and how these benefits relate to rehabilitation of juveniles. Many professionals involved in juvenile rehabilitation believe sport and recreation are beneficial adjuncts to treatment programming; however, it can be difficult to structure sport and recreation in ways that directly correspond to treatment goals. The purpose of this article is to provide insights for professionals working with juveniles on how sport and recreation programming can be an effective means of helping to achieve rehabilitation goals. Attention is given to approaches, particularly the Teaching Games for Understanding model (Bunker & Thorpe, 1982), which can be used to effectively link recreation and sport to the rehabilitation process. 相似文献