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61.
During the analysis of "seized samples", suspected of containing 4-methylmethcathinone (mephedrone) and N-ethylcathinone (ethcathinone) additional compounds were observed in the GCMS chromatogram. These compounds were suspected to be the corresponding phenylacetone isomers of mephedrone and ethcathinone respectively. These isomers are referred to as iso-mephedrone and iso-ethcathinone, respectively. The identity of these compounds was verified by synthesising the isomers from known starting materials and comparing them with the compounds found in the seized samples. Analytical data, GCMS, NMR and IR on these compounds are provided. Possible explanations for the presence of these compounds in the seized samples are explored. Contaminated starting material is one suggestion. Rearrangement of the propiophenone based product to the phenylacetone based product is also suggested. The reaction of the α-bromopropiophenone with a primary amine can also lead to the phenylacetone based product. The presence of these isomeric compounds in seized samples could be used to compare different samples and attempt to establish a common origin. 相似文献
62.
Power JD McGlynn P Clarke K McDermott SD Kavanagh P O'Brien J 《Forensic science international》2011,212(1-3):6-12
The ring substituted methyl isomers of methcathinone, 2-, 3- and 4-methylmethcathinone were analysed. The 2- and 3-isomers were synthesized. The 4-methylmethcathinone isomer is also known as mephedrone and has been widely studied. We present GCMS, NMR and IR data for the three isomers. We show that the three isomers can be separated by GCMS and that the IR spectra for the three compounds can be used to distinguish between them. A seized sample was analysed and it was found to contain 4-methylmethcathinone and benzocaine. 相似文献
63.
This article explores the meanings of ownership and shareholding in the context of the 2007 run on Northern Rock, its subsequent nationalization in 2008, and the resulting legal challenge brought by former shareholders. Drawing on evidence from a range of sources outside traditional legal and official doctrine, and from original empirical research, it focuses on the perspective and voices of local small individual shareholders in relation to shareholding, bank failure, and government responses to financial crisis. It tells the story of these individual shareholders against differing conceptions of share ownership rights and responsibilities, and from various angles, to show the many different subjectivities of corporate shareholding and ownership of enterprise of which orthodox legal and economic models take scant account. It concludes on a note of historic persistence in demand for proprietary shares in banking institutions, despite the differing levels of understanding and tolerance of equity risk among shareholders that our research reveals. 相似文献
64.
A person who is liable to defensive harm has forfeited his rights against the imposition of the harm, and so is not wronged if that harm is imposed. A number of philosophers, most notably Jeff McMahan, argue for an instrumental account of liability, whereby a person is liable to defensive harm when he is either morally or culpably responsible for an unjust threat of harm to others, and when the imposition of defensive harm is necessary to avert the threatened unjust harm. Others may favour a purely noninstrumental account of liability: one that looks only to the past behaviour of the potentially liable person. We argue that both views are vulnerable to serious objections. Instead we develop and defend a new view of liability to defensive harm: the pluralist account. The pluralist account states that liability to defensive harm has at least two bases. First, if an attacker is morally or culpably responsible for an unjust attack then he has forfeited what we call his agency right, and in doing so he has made himself partially liable to defensive harm. Whether the attacker is fully liable to defensive harm depends, however, on whether the imposition of defensive harm would infringe a different right held by the attacker: his humanitarian right. Humanitarian rights are rights to be provided with urgently needed resources or to be protected from serious harms when others can do so at reasonably low cost. We argue the pluralist account avoids the objections to which the instrumental and noninstrumental views are vulnerable, coheres with our intuitive reactions in a wide range of cases, and sheds new light on the way different rights combine to determine a person??s liability to suffer harm. 相似文献
65.
Błachut D Wojtasiewicz K Krawczyk K Maurin J Szawkało J Czarnocki Z 《Forensic science international》2012,216(1-3):108-120
The synthesis of the designer drug 4-methylthioamphetamine (4-MTA) has been carried out using the well-known Leuckart reaction in four versions. The treatment of 4-methylthiophenylacetone with formamide, mixture of formamide/formic acid, ammonium formate, and mixture of ammonium formate and formic acid followed by acid hydrolysis brought about the formation of 4-MTA contaminated with a number of impurities. The gas chromatography mass-spectrometry (GC-MS) analysis of the reaction mixtures allowed identification of the most prominent impurities, such as diasteromers of N,N-di-[β-(4-methylthiophenyl)isopropyl]amine, N,N-di-[β-(4-methylthiophenyl)isopropyl]methylamine, N,N-di-[β-(4-methylthiophenyl)isopropyl]formamide, the Schiff bases derived from 4-MTA and 4-methylbenzaldehyde (benzaldimine) and 4-methylthiophenylacetone (ketimine) as well as some heterocycles: 4-methyl-5-(4'-methylthiophenyl)pyrimidine, 4-(4'-methylthiobenzyl)pyrimidine, 2,6-dimethyl-3,5-di-(4'-methylthiophenyl)pyridine, 2,4-dimethyl-3,5-di-(4'-methylthiophenyl)pyridine. The correctness of identification was confirmed by independent synthesis of these compounds. Each synthesized reference compound was characterized by means of MS, (1)H and (13)C NMR, and IR methods. The stereochemistry of (RR/SS) diasteromer of N,N-di-[β-(4-methylthiophenyl)isopropyl]amine was confirmed by a crystallographic method. 相似文献
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Ballistics imaging technology has received national attention as a potent tool for moving the law enforcement response to violent gun criminals forward by linking multiple crime scenes to one firearm. This study examines the impact of ballistics imaging technology on the productivity of the Boston Police Department's Ballistics Unit. Using negative binomial regression models to analyze times series data on ballistics matches, we find that ballistics imaging technology was associated with a more than sixfold increase in the monthly number of ballistics matches made by the Boston Police Department's Ballistics Unit. Cost-effectiveness estimates and qualitative evidence also suggest that ballistics imaging technology allows law enforcement agencies to make hits that would not have been possible using traditional ballistics methods. 相似文献
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Blind proficiency testing is ideal for testing crime laboratory personnel because the elements of analyst bias and anticipation are removed. However, sending proficiency tests through the laboratory system as real casework is difficult. The substantial challenges with preparing and administering blind tests may prevent laboratory managers from initiating blind testing. In 2015, the Harris County Institute of Forensic Sciences committed to improving its crime laboratory’s proficiency testing program by adding blind tests. The goal was to test the whole system, from evidence receipt to report release. With careful planning, trial-and-error, and ongoing assessment of available resources, not only was the program proven to be feasible, but there was also clear understanding of how to optimize our program. In this article, we share our experiences, lessons learned, and program details to assist other forensic service providers with developing their own blind testing programs, which would ultimately lead to improved quality assurance. 相似文献