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121.
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   
122.
1963年2月下旬,毛主席题词“向雷锋同志学习”。3月5日,《人民日报》、《解放军报》、《中国青年报》等报刊发表以后,全国青年乃至全国军民热烈响应,迅速掀起了学雷锋活动的高潮。在毛主席题词之后,总政首长亲自向中共中央其他常委写报告,请求题词,在《解放军报》上刊登。刘少奇、周恩来、朱德、邓小平等同志陆续题了词。《解放军报》于3月6日首先刊载题词手迹后,进一步推动了全国学雷锋活动热潮。在中央常委题词过程中,周总理的一件事给我很大教育,至今印象很深。那段时间,我在解放军报社工作,正值上夜班。在周总理的…  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   
125.
In many countries it is left to the discretion of the court to accept or reject conclusions based on sampling procedures as applied to the total drug exhibit. As an alternative to this subjective approach, a statistical basis is presented using binomial and hypergeometric distributions to determine a lower limit for the proportion of units in a population which contains a drug, at a given confidence level. A method for calculating the total weight of a drug present in a population within a given confidence interval is also presented. In the event of no failures (all units sampled contain a drug), a sample size of six or seven units is generally sufficient to state that a proportion of at least 0.70 of the population contains a drug at a confidence level of at least 90%. When failures do occur in the sample, point estimation is used as the basis for selecting the appropriate sample size.  相似文献   
126.
A case of the sudden death of a 14-month-old girl due to massive hemorrhage in a primitive neuroectodermal tumor (PNET) is presented along with a review of the relevant literature. PNET is a rare, malignant brain neoplasm occurring predominantly in children.  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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