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161.
Amber R. Rose MSFS Monica Joshi PhD Marianne E. Staretz PhD Matthew Wood PhD Thomas A. Brettell PhD 《Journal of forensic sciences》2023,68(4):1148-1161
Aminoindanes are a class of novel psychoactive substances (NPSs) that have become more prevalent over the past decade. GC–MS is often utilized for identifying seized drugs and is well regarded for its ability to separate mixtures. However, certain aminoindanes have similar mass spectral data and require specific gas chromatographic stationary phases for separation. Derivatization is an alternative method that can be applied to GC–MS to enhance chromatographic results, providing more selective analysis in seized-drug identification. This study investigates derivatization techniques to provide options for forensic science laboratories in accurately identifying aminoindanes. Three derivatization reagents, N-methyl-bis(trifluoroacetamide) (MBTFA), heptafluorobutyric anhydride (HFBA), and ethyl chloroformate (ECF) were evaluated for the analysis of eight aminoindanes by GC–MS using two common gas chromatographic stationary phases, Rxi®-5Sil MS and Rxi®-1Sil MS. All three derivatization methods successfully isolated eight aminoindanes, including the isomers 4,5-methylenedioxy-2-aminoindane (4,5-MDAI), and 5,6-methylenedioxy-2-aminoindane (5,6-MDAI) that could not be differentiated prior to derivatization. Reduced peak tailing and increased abundance were observed after derivatization for all the compounds, and mass spectra of the derivatives contained individualizing fragment ions that allowed for further characterization of the aminoindanes. This excluded 4,5-MDAI and 5,6-MDAI as they shared the same characteristic ions and were only distinguishable by their retention times. All three derivatization techniques used in this study allow for successful characterization of the aminoindanes and give forensic science laboratories flexibility in their analysis approach when they encounter these compounds. 相似文献
162.
Hongwei Qiao PhD Litao Shao BS Jie Chen PhD Shan Jiang MS Mengxiang Su PhD Peipei Liu MS Bin Di PhD 《Journal of forensic sciences》2023,68(4):1277-1285
Caffeine is the most widely consumed psychoactive agent worldwide and has the potential for abuse, but studies monitoring caffeine abuse in China are scarce. This study aims to estimate the prevalence of caffeine abuse in northwest China and investigate the correlation between caffeine and other drugs in hair and nails using an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Fingernail clippings were collected from 376 participants in northwest China to detect caffeine and 13 other illicit psychoactive drugs and their metabolites. Paired hair and nail samples were collected from 39 participants to investigate the correlation between caffeine and other drugs in hair and nails. The samples were decontaminated, pulverized, and extracted by a high-throughput nail sample preparation method and analyzed by UPLC-MS/MS. The results showed a risk of caffeine abuse in northwest China, with concentrations ranging from 0.43 to 10.6 ng/mg for healthy volunteers, 0.49–246 ng/mg for caffeine abusers, and 0.25–363 ng/mg for drug addicts in community rehabilitation centers. Caffeine was detected together with other illicit psychoactive drugs and their metabolites. Furthermore, positive detection correlations were found between hair and nail samples. This study provides a current perspective on caffeine abuse in northwest China and demonstrates the practical use of UPLC-MS/MS for the simultaneous detection of caffeine and 13 illicit psychoactive drugs and their metabolites in hair and nails. The results highlight the potential of nails as a supplementary matrix when hair samples are unavailable and emphasize the need for handling caffeine carefully given its potential for abuse. 相似文献
163.
Pietro Zuccarello PhD Giulia Carnazza MSc Nunziata Barbera MD 《Journal of forensic sciences》2023,68(2):578-585
Vortioxetine is an antidepressant recently licensed in USA and EU for the treatment of major depressive disorder. Neither fatal case due to overdose nor data about postmortem concentrations on blood or other specimens have been reported. The aims of this study were the development and validation of a method for vortioxetine analysis by Liquid Chromatography Tandem Mass Spectrometry (LC–MS/MS) in postmortem samples and its application in an authentic case. The method was validated and applied on blood, vitreous humor, bile, brain, liver, kidney, and gastric content. After protein precipitation, the supernatant was directly injected into LC–MS/MS. Analysis was carried out by Multiple Reaction Monitoring (MRM) mode. The authentic case concerned a 38 years-old woman, affected by depression, who was found hanged at home. The method determined an acceptable sensitivity, selectivity, linearity, precision, and accuracy for all matrices. No interference was shown for all matrices. The matrices do not significantly reduce the peak intensity of vortioxetine. No carryover was shown. Toxicological analysis of the authentic case showed vortioxetine in blood (234 ng/ml), vitreous humor (10.5 ng/ml), brain (490 ng/g), lung (479 ng/g), liver (3751 ng/g), kidney (798 ng/g), bile (2267 ng/ml) and gastric content (253 ng/ml). Our case suggests that even at blood concentrations of vortioxetine equal to 234 ng/ml, the subject was able to stage and carry out the hanging. Vortioxetine concentrations found in the other cadaveric samples (biological fluids, organs, and gastric content) may be helpful to evaluate further similar comparable cases. 相似文献
164.
Pauline E. Leary PhD Koby L. Kizzire PhD Rebecca Chan Chao BS Michael Niedziejko BS Noah Martineau BS Brooke W. Kammrath PhD 《Journal of forensic sciences》2023,68(5):1601-1614
Potent synthetic opioids including fentanyl and its analogs are frequently encountered in the field and require detection and identification by first responders to maintain the safety of drug abusers, first responders, health-care providers, and the public at large. Due to the low concentration at which these substances may be encountered and the complicating matrices within which they may be dispersed, the use of portable gas chromatography–mass spectrometry (GC–MS) for their identification in the field offers great potential value. This research established that portable GC–MS is a useful method for the detection and identification of a large number of synthetic opioids, especially fentanyl and its analogs. In this study, 250 synthetic opioids and related substances including 210 fentanyl analogs were analyzed using portable GC–MS. It was concluded that 225 of the 250 (90.0%) opioids analyzed were successfully detected onboard at the time of analysis and identified as either the substance (55.2%) or an analog (34.8%). These outcomes have equivalent benefit for the field analysis of illicit drugs due to both initiating the same subsequent actions by first responders. 相似文献
165.
目的:检测X染色体上16个STR基因座的连锁不平衡情况,并对其遗传稳定性进行调查。方法从华东汉族群体选取女性无关个体500名、家系885个,提取血样DNA,利用自主研发的IDtyperX-16试剂盒对16个X-STR基因座进行多重PCR扩增和毛细管电泳分型,使用PowerMarker v3.25软件对基因座进行连锁不平衡检验,并分析各个基因座的突变率。结果16个X-STR基因座彼此之间不存在连锁不平衡现象;有10个基因座检见突变,其中DXS6809和DXS7132的突变率均高达0.0048。结论对于IDtyperX-16试剂盒中的16个X-STR基因座,在亲权鉴定中应用时可运用乘积原理计算似然率,但若遇到不符合遗传规律的情形(尤其是DXS6809、DXS7132基因座),应考虑存在突变的可能。 相似文献
166.
British local authorities and their partners are increasingly developing new ways of working together with local communities. The nature of this co-working, however, is complex, multi-faceted and little understood. This article argues for greater clarity of thinking on the topic, by analysing this co-working as a form of political co-governance, and drawing attention in particular to issues of scale and democracy. Using evidence from a study of 43 local authority areas, 16 authorities are identified where co-governance is practised, following three main types of approach: service-influencing, service-delivering and parish council developing. It is concluded that strengthening political co-governance is essential for a healthy democracy. 相似文献
167.
Zeger Van der Wal 《国际公共行政管理杂志》2013,36(14):1030-1043
In this article, we compare how administrative and political elites in The Netherlands, the European Union, and the United States perceive and prioritize four key public values—responsiveness, expertise, lawfulness, and transparency. Our data from 94 in-depth interviews show that political elites and administrative elites differ most in their perception and prioritization of expertise and transparency and less in responsiveness and lawfulness. Interestingly, these politico-administrative value differences largely hold across the institutional settings we study. Theorizing on our results, we formulate eight propositions for future studies. Our study contributes to public values research by using qualitative methodology and including politicians. 相似文献
168.
Hou Minyue 《Asian Journal of Political Science》2013,21(3):344-362
The Tiananmen events of June 1989 shattered the dream of a special relationship between China and Australia, making human rights one of the major issues to be addressed in their bilateral relations. Though differences emerged, they still needed manageable and constructive linkages because both of them were fully aware that confrontation could damage their common interests in economic prosperity and regional peace and stability. Consequently, the engagement in human rights was the mutual demand and pursuit between Beijing and Canberra. By means of engagement, Canberra expected that with the growth of China's economy and reform this moderate approach would bring about to China better conditions for more progress in human rights, though it might be at a slow speed. In the process of China's post-Tiananmen evolutionary human rights diplomacy changes, Australia was one of the countries to be won over by China in facilitating its policy implementation. Admittedly, China's bilateral dialogue approach and technical cooperation with Australia and some other Western countries contributed to the successive failure of the American attempt to take multilateral actions to pass an anti-China resolution in the UN Human Rights Commission (replaced by the UN Human Rights Council in March 2006). Meanwhile, China had to take such steps as responding to concerns on rights issues raised by its dialogue partners and accepting and implementing UN human rights instruments to maintain the engagement approach. Resultantly, the process of China's engagement with Australia and other Western states in human rights is also a process of its learning how to deal with Western pressure constructively and how to improve human rights at home. 相似文献
169.
Ramses Amer 《Asian Journal of Political Science》2013,21(2):109-125
This article examines the relevance of Zartman's “ripeness theory” to explain the resolution of the China‐Vietnam conflict. It analyses the core concepts of this theoretical approach to the study of conflict resolution, and evaluates the explanatory value of this approach for understanding the resolution of conflict in specific cases such as the China‐Vietnam conflict. The article identifies three core concepts in this theory, including “hurting stalemate”, “ripe moment”, and “ripe for resolution”. But from the analysis of the China‐Vietnam conflict, it could not discern any of these concepts or stages in the process of conflict resolution in this particular case. Thus, it concludes that Zartman's theoretical approach does not have an explanatory value for the case of the resolution of the Sino‐Vietnamese conflict. 相似文献
170.
Nathan Stocker 《Local Government Studies》2013,39(5):791-808
Local governments have two primary components: elected representatives and employed staff. The relationship between these two groups has significant impacts on local authority operation. Two key theoretical models used to characterise these relations, the well-established Politics/Administration Dichotomy and the recently conceived Complementarity Model, are employed here to explore relationships in New Zealand councils. Results show varying views regarding whether the separation of staff and elected representatives (councillors) is based on their respective roles or inputs. A role-based separation emphasises distinct ‘realms’, with elected representatives controlling policy making and staff controlling the implementation of policy. This approach supports a hegemonic relationship and embodies the Politics/Administration Dichotomy. On the other hand, an input-based separation emphasises the issues that each group should focus on, with councillors integrating community desires and staff contributing their technical expertise. The latter lends itself to interactive processes and is consistent with the Complementarity Model. Neither input nor role-based relationships are inherently superior; various empirical factors influence the suitability of each. This suggests that it is advantageous to have multiple theoretical models accounting for alternative local government relationship structures, but future research is needed to clarify the ‘best’ options for different contexts. 相似文献