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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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In the wake of the 1990 amendments to the Clean Air Act, localities across the United States initiated public information campaigns both to raise awareness of threats to air quality and to change behavior related to air pollution by recommending specific behavioral changes in the campaign messages. These campaigns are designed to reduce the health hazards associated with poor air quality and to avoid federal sanctions resulting from the failure to meet air quality standards. As in many other communities across the country, a coalition of government agencies and businesses initiated a public information campaign in the Atlanta metropolitan region to reduce certain targeted behaviors, mainly driving. A two‐stage model used to analyze data from a rolling sample survey shows that the centerpiece of the information campaign—air quality alerts—was effective in raising awareness and reducing driving in a segment of the population. When the overall information campaign was moderated by employers' participation in programs to improve air quality, drivers significantly reduced the number of miles they drove and the number of trips they took by car on days when air quality alerts were sounded. Public information campaigns can be successful in increasing awareness, but changing well‐established behaviors, such as driving, is likely to require institutional mediation to provide social contexts that support the behavioral change, as well. © 2003 by the Association for Public Policy Analysis and Management.  相似文献   
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Report of an unusual finding of bones on the shore of the Baltic Sea. Although the morphological findings appeared similar to a human foot skeleton, a quick identification as sea dog bone was possible.  相似文献   
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On the one hand the following case demonstrates the problems of finding a dead body in the bathroom and on the other hand the importance of postmortem x-ray examinations. The corpse of an 65-year-old woman was discovered in her bath tub. At the body's feet there was a hair dryer. Investigations concerning murder were negative, circumstances appeared to be unsuspicious. That was why a postmortem examination was not performed. -4 years later murder had to be considered. After manual strangling the deceased and the hair dryer were layed into the bath tub. The corpse was exhumed and taken to a forensic autopsy. It was found that the hyoid bone and the superior horn of the thyroid cartilage were both fractured on the right. Damages caused by the preparation itself were excluded by using serial roentgenographs. These observations in combination with histological findings and the results of further investigations convincingly supported the suspicion of strangling by hand.  相似文献   
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A new solid-phase extraction procedure for the determination of cocaine and benzoylecgonine in amniotic fluid, using high flow co-polymeric sorbents is reported. The recoveries of cocaine and benzoylecgonine within the range 0.1-1 mg/l were 95.7% and 50.3%, respectively. The use of high-flow sorbents allowed the easy extraction of amniotic fluid regardless of sample viscosity or physical nature. The use of these solid-phase columns provided many advantages over the more commonly used solvent extraction, including an increase in extraction speed and efficiency, reduced operator time, reduced solvent use and disposal volumes and exceptional extract quality. Further, the determination of amniotic fluid obtained from pregnant cocaine users may provide important information about handling of cocaine by the fetus at various gestational ages. The procedure was successfully applied to amniotic fluid from suspected cocaine abusers.  相似文献   
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Dilutions of 100 serum samples of various GM phenotypes were dotted onto a nitrocellulose membrane. The serum dot-blots were detected with peroxidase-labeled anti-G3M T monoclonal antibody (anti-G3M T MAb). Up to a 1 : 256 dilution could be G3M T-typed correctly. By use of anti-G3M T MAb and peroxidase-labeled anti-mouse IgG or the biotin-avidin system instead of use of labeled anti-G3M T MAb, up to a 1 : 512 or 1 : 1024, respectively, dilution was typable. As with previous work with G3M G MAb, the dot immunobinding (DIB) method for G3M T typing was found very simple and practical.  相似文献   
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