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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   
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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   
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This article conducts an analysis of director’s liability in listed firms using modern finance theory. The paper describes how the use of special general clauses in Danish law regulates director’s liability. It is shown how risk and return combinations may assist in determining whether management has violated the business judgment rule. The analysis shows that this legal doctrine is optimal from an economic perspective. The article introduces the concept of “temporal relatively of the shareholder equality principle” which can be used to determine whether the interests of minority shareholders have been set aside. It is shown that the principle of shareholder equality must be subjected to both an ex ante, as well as an ex post assessment. Moreover, courts should be reluctant to interfere in situations where there has been an unequal distribution of gain (or loss) ex post. The theoretical arguments are illustrated by analyzing a leading Danish court case that involved the squeeze out of minority shareholders in the Danish telecom company. The paper also analyzes the incentive effects of derivate suits and suits commenced by individual shareholders. It is shown that the former creates a free rider problem whereas in the latter situation, shareholders are not fully able to internalize their externalities.  相似文献   
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Prevalence differences in depressive symptoms between the sexes typically emerge in adolescence, with symptoms more prevalent among girls. Some evidence suggests that variation in onset and progression of puberty might contribute to these differences. This study used a genetically informative, longitudinal (assessed at ages 12, 14, and 17) sample of Finnish adolescent twins (N = 1214, 51.6% female) to test whether etiological influences on depressive symptoms differ as a function of pubertal status. These tests were conducted separately by sex, and explored longitudinal relationships. Results indicated that pubertal development moderates environmental influences on depressive symptoms. These factors are more important on age 14 depressive symptoms among more developed girls relative to their less developed peers, but decrease in influence on age 17 depressive symptoms. The same effects are observed in boys, but are delayed, paralleling the delay in pubertal development in boys compared to girls. Thus, the importance of environmental influences on depressive symptoms during adolescence changes as a function of pubertal development, and the timing of this effect differs across the sexes.  相似文献   
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