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51.
Karolina Nowak M.Sc. Paweł Szpot Ph.D. Marcin Zawadzki Ph.D. 《Journal of forensic sciences》2020,65(5):1784-1790
We present results of our study on the stability of 4-chloromethcathinone (4-CMC) in authentic postmortem peripheral blood and vitreous humor samples. The stability of 4-CMC was determined in postmortem blood samples (for a period of 90 days) and vitreous humor (30 days) at three different temperatures: −15°C, +4°C, and + 23°C. The analyses were carried out using ultra-high-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). In both materials, the lowest 4-CMC stability was demonstrated at room temperature. The blood samples stored in a freezer (−15°C) showed stability for the entire study period (90 days), while in the case of the vitreous humor sample stored at the same temperature the concentration of the substance decreased by 53% after 30 days. The study carried out in authentic postmortem blood and vitreous humor samples confirms the previous reports of 4-CMC instability in biological material. Authors suggest that the biological material should be stored frozen until analyses are carried out as soon as possible after collection of the material. 相似文献
52.
Peter E. Mulherin 《澳大利亚政治与历史杂志》2020,66(4):633-645
The decision to go to war in Australia remains the prerogative of the Executive. The lack of parliamentary authorisation of perhaps the most significant decision a democracy can make has seen sustained, but unsuccessful, efforts to reform legislation. In the wake of the costly invasion and occupation of Iraq in 2003, repeated calls for legislative reform of Australia's war powers have failed to find traction amongst Coalition and Australian Labor Party (ALP) leadership. Lamenting the lack of transparency and accountability in the current system, those favouring legislative reform would see authorisation of combat missions placed in the hands of Parliament. However, given the lack of support from either of the major parties, any legislative reform remains unlikely. Given this impasse, this article argues that a compromise option, in the form of a new war-powers convention, may be a small step towards democratising the decision of going to war. While not legally binding, this constitutional convention would represent an agreement by the major parties that overseas combat operations will be properly debated in Parliament. 相似文献
53.
Journal of Youth and Adolescence - 相似文献
54.
LORRAINE VAN BLERK JONATHAN MENDEL ANDREA RODRIGUEZ FERNANDO L. FERNANDES IRENE RIZZINI 《Bulletin of Latin American research》2019,38(3):284-299
Sport's transformative potential is known to support marginalised children, to deal with traumatic experiences and instil positive values; yet hosting mega sporting events (MSEs) can have negative impacts. Drawing on participatory research with favela‐based children during the 2014 World Cup in Brazil, this article argues that MSEs bring a macro‐securitisation of urban life, which causes considerable harm. This paper also suggests that the inclusion of children's voices in advocacy debates can challenge top‐down securitisation and might allow MSEs to foster further positive social transformation. Therefore, juxtaposed with causing harm, macro‐securitisations can open opportunities for children to take action and have their voices heard. 相似文献
55.
Anne L. Schneider 《Journal of policy analysis and management》2020,39(1):288-292
56.
Victor A. Albert 《Bulletin of Latin American research》2021,40(1):84-99
Brazil's Movimento de Trabalhadores Sem Teto (MTST, Homeless Workers' Movement) has grown dramatically in recent years. This growth was partly provided for by the use of a large government housing programme, Minha Casa Minha Vida (MCMV, My House My Life), which allowed the MTST to construct housing for its members and swell its ranks with thousands of new members. Yet some have argued that the MCMV programme used by the MTST may compromise the autonomy of civil society organisations. This article, by contrast, argues that while the MCMV programme encouraged bureaucratic practices, it also helped to promote the cultural politics of the MTST. 相似文献
57.
58.
This study developed a composite machine learning algorithm for attribution of materials of forensic interest (like ammonium nitrate) to original sources. k-nearest neighbor and random forest models were used for source elimination and classification, respectively, in a two-step, composite algorithm based on particle color, size/shape, and trace element concentration features. Novel approaches for simulation to supplement within-source reference features based on empirically measured multi-lot analyses, an improved hold-one-lot-out method for cross-validation, an assessment of the likelihood of the presence of a reference sample, fusion of the source probabilities from the respective classification models, and the calculation of metrics for assessing ensemble sourcing performance are described. Excellent sourcing predictions were obtained; the sourcing algorithm identified the correct source as the top choice 89% of the time, and the correct source was identified to be an average of 2.7 times more likely than the most likely incorrect source. 相似文献
59.
This paper examines the power to prorogue (or suspend) Parliament following the 2019 prorogation controversy in the UK. We outline the legal basis of prerogative-based prorogation, survey its uses in the UK and other Westminster systems, and compare it with equivalent rules in other European parliamentary democracies. The comparative perspective highlights the outlier status of the UK among comparable European democracies. In the UK, the absence of explicit legal limits on the use of prorogation gives the executive exceptional scope to employ the power for political purposes to sidestep Parliament. We conclude by discussing the implications of these findings for current discussions about the desirability of reforming the UK’s prorogation rules and placing express legal limits on the executive’s power. 相似文献
60.