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81.
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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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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This article outlines the new regionalism movement and its metropolitanagenda, reviews federal efforts to promote new regionalism underISTEA and TEA–21, considers how the new federal policieschanged the role of metropolitan planning organizations (MPOs)in transportation planning by examining the MPO for the Louisvillemetropolis, and assesses the MPO process in Louisville. Thelocal decision of whether to build a new bridge across the OhioRiver was a major test of the enhanced MPO process. Federaltransportation policies enhanced regional coordination and cooperationin transportation planning in the Louisville metropolis resultingin a consensus plan to build two bridges across the Ohio River.However, the MPO process did not lead to the development ofa metropolitan-wide interest or perspective. Moreover, the newregionalist agenda was not advanced because sprawl was not afactor in the decision on whether and where to build the bridges.  相似文献   
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This paper explores the capacity of alternative theoretical perspectives to explain the self-reported criminality of black and white young adult females. When criminal involvement is regressed on the theory operation-alizations separately by race, a key difference emerges: For white women, significant effects are clustered in the social-psychological theory groups (bonding, attitudes, and maturation), but for the black women the social-psychological variables have only scattered and inconsistent eflects. Instead, for black women structural indicators emerge as the important predictors of criminal involvement.  相似文献   
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Most studies that consider the factors influencing the decision to leave an abusive relationship rely on retrospective, self-report data. In addition to the biased samples that are frequently obtained in such investigations, the methodological shortcomings of survey research limit its explanatory power, particularly when applied to such sensitive topics as family violence. This report introduces an alternative method for studying the decision to leave an abusive relationship. Forty-five men and 68 women were studied using an experimental computer game of an abuse-like relationship. The tendency to leave this relationship was measured under four differing conditions of severity and frequency of abuse. A logit analysis revealed that the frequency of abuse was more consequential to women's decisions to leave, while severity of abuse was more salient for men. In addition, the hypothesized model, including frequency of abuse, severity of abuse, and locus of control, fits well for women but not for men. The implications of these findings, as well as the validity and future application of experimental games, are discussed.  相似文献   
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Comparison of a suspected biter's dental arches with the patterned injury of a bite mark is especially difficult when the bite occurs in an anatomic location with a small radius of curvature or with complex or compound curves. The authors present two case reports in which human skin was used as a template for the reproduction of a bite. In one case the victim's skin was used; in the other, the skin of a anatomically similar person was used. The use of inked dental casts, photography, and transparent overlays significantly reduced the errors common to analysis of bite marks in these highly curved areas.  相似文献   
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