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In motorcycle accidents involving two riders, medicolegal identification of the driver is necessary when one or both riders die. It is particularly important in the latter case, because the survivor almost always insists that he or she was not driving. One characteristic injury that distinguishes the driver from the passenger is inguinal contusion-laceration (accompanied internally by pelvic fracture). This injury, caused by collision of the pelvis with the fuel tank, identifies the driver.  相似文献   
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Kindergarten policy varies widely both across and within states. Over the past decade, a number of states have instituted a full‐day kindergarten requirement and others are considering it as a way to increase educational achievement. Many parents also support full‐day kindergarten as a source of child care. This paper uses the Early Child Longitudinal Study–Kindergarten Class of 1998–1999 to evaluate the efficacy of this policy. In ordinary least squares, probit, county fixed effects, and instrumental variables models, we find that there are initial benefits for students and the mothers of students who attend full‐day kindergarten, but that these differences largely evaporate by third grade. Contrary to claims by some advocates, attending full‐day kindergarten is found to have no additional benefit for students in families with income below the poverty threshold. © 2006 by the Association for Public Policy Analysis and Management  相似文献   
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In the statistical interpretation of forensic glass evidence it is standard practice to make the assumption of homogeneity of the refractive index (RI) of the source glass, or of localized homogeneity. However, the work of Locke and Hayes showed that, for toughened windscreen glass, this assumption might not be true. This work is well cited, but there appears to have been little follow-on published research. Furthermore, the toughening process is something known to affect the refractive index, and is a process that float glass does not undergo. Float glass is a major component of casework in New Zealand and for that reason it would be interesting to know whether the findings of Locke and Hayes apply when dealing with float glass. In this paper we describe an experiment similar to that of Locke and Hayes, systematically examining the variation of RI in a pane of float window glass. It was found that, although there were no systematic differences in refractive index, there were observable differences across the pane.  相似文献   
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Family courts and child welfare agencies across the country are charged with protecting the safety of our children. That mission has become more challenging with increasing federal legislation and decreasing funding. In Buffalo, N.Y., the Family Court and the Department of Social Services have teamed up to respond to this challenge. With minimal additional staffing and resources, they have led a collaboration of agencies and service providers to change the way business is done in child welfare. By engaging each other in an interagency system change effort, the amount of time children spend in foster care has been reduced. The collaboration has been able to accomplish in a relatively short time what no agency had previously been able to accomplish on its own. The beneficiaries have been the children and families of Erie County.  相似文献   
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