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71.
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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Postmortem investigation is increasingly supported by Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). This led to the idea to implement a noninvasive or minimally invasive autopsy technique. Therefore, a minimally invasive angiography technique becomes necessary, in order to support the vascular cross section diagnostic. Preliminary experiments investigating different contrast agents for CT and MRI and their postmortem applicability have been performed using an ex-vivo porcine coronary model. MSCT and MRI angiography was performed in the porcine model. Three human corpses were investigated using minimally invasive MSCT angiography. Via the right femoral artery a plastic tube was advanced into the aortic arch. Using a flow adjustable pump the radiopaque contrast agent meglumine-ioxithalamate was injected. Subsequent MSCT scanning provided an excellent anatomic visualization of the human arterial system including intracranial and coronary arteries. Vascular pathologies such as calcification, stenosis and injury were detected. Limitations of the introduced approach are cases of major vessel injury and cases that show an advanced stage of decay.  相似文献   
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The development of numerical human models is a topic of current interdisciplinary research. In the field of automotive safety these models can be applied for the optimization of protection systems. In forensic research human models can be used for the investigation of injury mechanisms and for the prediction and reproduction of injury patterns. However, up to now human models have been validated on the basis of PMHS tests without considering the effects of muscle activity. This paper shows two experimental volunteer test set-ups for the generation of experimental validation data. In a pendulum set-up the influence of muscle activity on the human kinematics was investigated. A drop test set-up was developed for the analysis of the effects of muscle activity on impact response characteristics of muscle tissue. Experimental results, presented in this paper, can be used for the validation and optimization of active numerical human models.  相似文献   
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This paper seeks to contribute to the growing literature on the entrepreneurial university by mapping knowledge exchange relationships of entrepreneurial faculty in a comprehensive manner and also capturing faculty attitudes towards measures taken by the university administration to promote entrepreneurship. We report on an exploratory study of Sussex University, a medium-sized, research-oriented university, which launched technology transfer activities in the mid-1990s. Our results show that, in spite of a comparatively late start, a considerable number of researchers engage in knowledge exchange processes with industry and other non-academic partners. We present evidence that suggests faculty in the social sciences and humanities as well as natural sciences and engineering maintain links to industrial partners, including multinational corporations. Furthermore, our observations indicate that schools differ in the way their faculty engage in university–industry collaborations. Further differences can be observed with respect to faculty attitudes towards technology transfer and awareness of the university’s respective codes of practice.
Arianna MartinelliEmail:
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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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