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Traditional pollen preparation techniques provide clear residues for pollen identification; however, such methods are time-consuming, requiring repeated centrifugation, heating, and digestion with high-concentration hazardous chemicals. Tobacco leaves can effectively trap environmental pollen due to hairy surface and terpene-rich exudates. A new tobacco sample processing method was developed by using different extraction chemistry with surfactant. Marlboro Gold cigarettes were employed as model samples for method development. Parameters critical for pollen extraction, which include number of cigarette sticks used, extraction solution, and extraction temperature, were optimized. By using 1% dishwashing detergent to treat three cigarettes at room temperature, the improved method was able to recover sufficient pollen for microscopic analysis in three repeated centrifuge-washing steps and omit hazardous chemicals involved in traditional methods. We focused on the pollen of common ragweed (Ambrosia artemisiifolia), a plant native to North America, as an indicator to differentiate genuine and counterfeit U.S. brand cigarettes. Results from analyzing randomly purchased genuine (authenticated by forensic examination) and known counterfeit Marlboro Gold provided by law enforcement revealed that a significant amount (39%) of Ambrosia were consistently present in all genuine samples, while counterfeit contained none or only trace count. Similar results were found in other counterfeit U.S. brand cigarettes (all seized in the U.S.) involved in this study as well. Lack of Ambrosia in cigarette strongly indicates the product was not originated in the United States.  相似文献   
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The human brain shows a very high density of functionally important structures. Even small lesions may therefore cause clinical symptoms. Penetrating gunshots to the head are presumed to cause immediate incapacitation by subsequent disturbance of cerebral functions. The authors discuss anatomical and functional principles of the terms action, capacity to act and incapacitation and report two illustrative cases with lack of incapacitation following gunshots to the head.  相似文献   
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This essay and review on criminal network analysis provides an introduction to the special issue “Human Capital and Social Capital in Criminal Networks”. It traces the history of the application of network analysis in the study of organized crime since the early 1970s. It argues that while criminal network analysis has brought a new level of methodological rigor to the study of organized crime, a number of limitations have become apparent. These include the problem of missing data and the challenges encountered in adequately capturing latent structures, individual characteristics of network members and socio-ecological conditions.  相似文献   
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