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871.
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Baby monitor     
Pinker S 《Time》2001,158(7):33
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Product tampering, as detailed by the Federal Anti-Tampering Act of 1983 (1), is a felony punishable by both fine and imprisonment. The rationale for product tampering ranges from pranks and attention seeking acts to extortion, terrorism, and homicide. One such case submitted for analysis involved four medical syringes found in a supermarket and suspected of being used to tamper with various products. One of the syringes was found piercing a pear while the other three syringes were found with needles exposed in other parts of the supermarket. Microscopic analysis was used to collect residue from the syringe barrels and the pear. A multidiscipline approach involving SLM, PLM, including microchemical analysis, FTIR, and GC/MS analyses, performed on the residual liquid found in the syringe barrels and in the suspect pear, confirmed the presence of cocaine. This multidisciplinary approach is often necessary when there is a possible health risk to the public and rapid response is important. With this approach, it was quickly determined which drugs or poisons were used in this tampering.  相似文献   
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Variation in the mitochondrial DNA (mtDNA) control region as detected by sequence-specific oligonucleotide (SSO) probes is described for 2282 individuals from African-American, European-American, and Hispanic subpopulations from five broadly defined regions of North America (Northeast, Southeast, Central, Northwest, Southwest). Population diversity estimates were uniformly high for all subpopulations and for each major ethnic group. Only the Pennsylvania Hispanic group was remarkable with respect to its mitochondrial DNA types, having both six low frequency population specific types (ranging from 1.2-8.6%) and three high frequency shared types (10-20% each). There was no statistically significant subpopulation heterogeneity present within any of the three major groups at either the subpopulation level or the regional level (p > 0.01). However, statistically significant heterogeneity was measured when comparing the three major groups to each other, with the variance component attributable to this large division accounting for 18.60% of the total variance (p < 0.001). Overall mtDNA is a satisfactory forensic typing locus within broadly defined African-American, European-American, and Hispanic groups from North America, based on the high diversity estimates and absence of heterogeneity, as characterized by SSO typing.  相似文献   
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When the anterior thoracic wall is within the hypostatic area, postmortem lividity in the region of the nipples and their immediate vicinity is less intense or absent. Where hypostatic skin haemorrhages (so-called vibices) are present, these are also found outside the areola of the nipple only. This phenomenon is visible not only externally, but is particularly pronounced on the cut surface. A possible explanation may be the different distribution pattern of connective tissue, smooth muscles and blood vessels inside and outside the areola mammae. Based on 13 cases from the forensic autopsy material--mostly drug related deaths--the macromorphological findings and their histological correlates are presented.  相似文献   
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The authors tested whether use of an electro shock weapon (stun gun) leaves marks on skin which can be found in an exterior examination. On pig skin such marks could not be produced postmortally. An experiment on one of the authors caused reddish skin marks which persisted for about 2 h. Inability to act as promised by the weapons' manufacturers did not occur in our experiments, exactly as previously described by other authors. Use of an air tester which shoots barbed electrodes ought to produce bleedings if the electrodes actually penetrate the skin.  相似文献   
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