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181.
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A simple and rapid method for the analysis of carbohydrates in heroin samples by capillary electrophoresis utilizing a borate complexation method is described. Separations were performed using an uncoated fused silica capillary, 50 cm x 50 micro I.D. x 360 microm O.D. with an effective separation length of 9 cm. The system was run at 60 degrees C with an applied voltage of -8 kilovolts. Injection of each sample was for 1 sec at -50 mbar. UV detection was employed with the wavelength set at 195 nm. The background electrolyte consisted of 65 mM borate, pH 12.0. Samples and standards were prepared in the run buffer containing 2 mg/mL of mannose as an internal standard. Under these conditions a test mixture containing glucose, sucrose, lactose, mannitol and mannose as an internal standard was resolved within 5 min. The method was used to determine the concentration of carbohydrates in heroin seizure samples and synthetic heroin samples. The results were in good agreement with the reported values.  相似文献   
183.
This Article explores the evolution and interaction of the legal and cultural categories "food" and "drug" from the late nineteenth century to the present. The federal statutory definitions of "food" and "drug" have always been ambiguous and plastic, providing the FDA with significant regulatory flexibility. Nevertheless, the agency is not necessarily free to interpret the definitions however it chooses. "Food" and "drug" are not only product classes defined by food and drug law, but also fundamental cultural concepts. This Article demonstrates that the FDA, as well as Congress and the courts, have operated within a constraining cultural matrix that has limited their freedom to impose their preferred understandings of these categories on American society. Nonetheless, history also provides ample evidence that lawmakers possess substantial power to mold the legal categories of "food" and "drug" so as to advance desired policies. One explanation for this regulatory flexibility in the face of deep-seated cultural conceptions is the indeterminate nature of the extralegal notions of "food" and "drug." The terms, as commonly understood, embrace nebulous, overlapping, and constantly evolving realms. Moreover, the relationship between culture and law is not a one-way street with respect to these categories. Although the regulatory apparatus has always had to take into account the extralegal understandings of "food" and "drug," the law in turn has exerted significant influence over their meaning in broader culture.  相似文献   
184.
The recovery and identification of latent fingerprints from a crime scene are crucial to many investigations. The cyanoacrylate (superglue) fuming method (CFM), which develops fingerprints by growing a polymer coating over the print residue, is a powerful method but encounters severe limitations when prints are aged or exposed to harsh environmental conditions. We examine the aging process and how the changes that occur to a fingerprint residue over time influence the growth of polymer during development. We identify loss of initiator by erosion and degradation that, when coupled with a loss of water from the print residue, result in a decreased ability to polymerize ethylcyanoacrylate. Then, we present a methodology by which the ability of aged latent fingerprints to polymerize ethylcyanoacrylate is recovered. Two print enhancement agents, acetic acid and ammonia, are demonstrated to improve the growth of polymer from the print ridges by over an order of magnitude, while retaining the integrity of the print structure. Comparison between the two enhancement agents indicate that the enhancement occurs due to ridge coating by the ammonia or acetic acid and pH control of the latent print.  相似文献   
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Motor vehicle driver fatalities (≥18 years) from the files at Forensic Science South Australia were reviewed from January 2008 to December 2018 for cases in which either positive blood sample for methamphetamine (MA) or an illegal blood alcohol concentration (BAC) >0.05g/100 ml were found. Three hundred driver deaths were found with MA detected in 28 cases (age range 21–62 years; ave. 37.8 years; M:F 23:5). Hundred and fifteen cases with a BAC > 0.05 g/100 ml were identified (age range 18–67 years; ave 35.7 years; M:F 95:20). No change was found in numbers of MA cases, although alcohol cases showed a significant decline (p < 0.001). Drunk driving-related fatal crashes tended to occur in the evening (5 p.m. to 11 p.m.), while MA-related fatal crashes had a longer peak extending from late evening until late morning (11 p.m. to 8 a.m.). This study has demonstrated that while roadside breath testing, legislative changes, and increased monitoring have resulted in reduced levels of drunk driving, similar safety countermeasures have had negligible effects on MA use in drivers. Continued monitoring of MA use by drivers will, therefore, be necessary to assess the possible effects, or not, of new countermeasures.  相似文献   
188.
Research on comparative authoritarianism has tended to neglect spatial approaches to the politics of non-democratic states. This article argues that spatial theory offers a useful framework for exploring extraterritorial security practices designed to counter political opposition among migrant and exile communities. A case study of Uzbekistan explores how the state responded to the perceived security threats posed by rapidly growing communities of labor migrants and the activities of many political and religious activists in exile. The security services developed a network of extraterritorial intelligence and security mechanisms – including surveillance, detention, interrogation and forced returns – to pre-empt or respond to any perceived threats to the regime emanating from abroad. These security practices extended the state in complex ways beyond its borders, resulting in new “state spaces” that reproduced elements of domestic repression in other jurisdictions. The article suggests that such extraterritorial practices are typical of contemporary authoritarian regimes, as such states seek to manage the spatial challenges produced by mass global migration, international financial flows, and transnational processes of knowledge production.  相似文献   
189.
Suicidal acts of terrorism conducted by lone actors independently of overseas command and control networks currently dominate the European landscape. Intelligence suggests from a population of fifty-two attackers between 2012 and 2017, at least 75% had a history of chronic substance abuse. Almost exclusively, Muslims do not engage in 12-step recovery programmes like Alcoholics Anonymous. We hypothesize that as both an ideology and agent of socialization, Islamic fundamentalism provides a structurally equivalent alternative. Yet, it is a programme that inadvertently directs a minority of vulnerable men along a pathway towards isolation, obsession, resentment and finally martyrdom.  相似文献   
190.
Grant Havers's Leo Straus and Anglo-American Democracy: A Conservative Critique seriously misrepresents Strauss's thought, largely as a result of Havers's determination to use the history of political philosophy for partisan purposes of his own, unlike Strauss's determined and meticulous effort to learn fromthe greatest philosophic writers both ancient and modern.?  相似文献   
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