The Stability of 4-Chloromethcathinone in Blood and Vitreous Humor

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.     

大型公用建筑火灾时人员应急疏散评价模型研究

应急疏散措施的优劣是评价大型公用建筑安全水平高低的重要标准之一。本文通过分析影响大型公用建筑应急疏散措施有效性的主要因素,参照相关法规及大型公用建筑应急疏散时各指标因素的层次,建立了大型公用建筑应急疏散评价模型。将该模型应用到某高校图书馆的应急疏散评价过程中,验证了模型的准确性,为建筑物火灾人员应急安全疏散提供了切实可行的参考依据。     

我国毒品泛滥的新动向

近50年来，毒品蔓延的范围已扩展到全世界五大洲200多个国家和地区，成为全球性的问题。联合国麻醉品管制署提供的资料显示，上世纪50年代，全球的吸毒人数约为910万，而目前已是2亿多人。我国毒品泛滥情况依然严重，毒品犯罪案件仍居高不下，毒品犯罪趋于国际化、网络化、隐蔽化，吸毒人员呈几何级数式增长，毒品消费市场的不断滋生扩大。本文详尽综述了近几年我国毒品泛滥的一些新情况和趋势。     

城市管理综合执法手段的合比例原则考察

城市管理综合执法手段的实质就是相对集中行政处罚权行使的具体方法、方式,有其丰富的表现形式,实践中由行政综合执法机关依法进行自由裁量。通过运用比例原则的三个子原则剖析实践中城市管理综合执法手段的行使,提出从立法、执法和司法三个方面来运用比例原则以对城市管理综合执法手段的行使进行有效控制。     

Comparative Politics and the Synthetic Control Method

In recent years, a widespread consensus has emerged about the necessity of establishing bridges between quantitative and qualitative approaches to empirical research in political science. In this article, we discuss the use of the synthetic control method as a way to bridge the quantitative/qualitative divide in comparative politics. The synthetic control method provides a systematic way to choose comparison units in comparative case studies. This systematization opens the door to precise quantitative inference in small‐sample comparative studies, without precluding the application of qualitative approaches. Borrowing the expression from Sidney Tarrow, the synthetic control method allows researchers to put “qualitative flesh on quantitative bones.” We illustrate the main ideas behind the synthetic control method by estimating the economic impact of the 1990 German reunification on West Germany.     

Comparative Analysis of the Chemical Profiles of 3,4-Methylenedioxymethamphetamine Based on Comprehensive Two-Dimensional Gas Chromatography-Time-of-Flight Mass Spectrometry (GC × GC-TOFMS)*

Abstract: The chemical profiling of illicit drugs is an important analytical tool to support the work of investigating and law enforcement authorities. In our work, comprehensive two‐dimensional gas chromatography–time‐of‐flight mass spectrometry (GC × GC‐TOFMS) combined with nontargeted, pixel‐based data analysis was adapted for the chemical profiling of 3,4‐methylenedioxymethamphetamine (MDMA). The validity and benefit of this approach was evaluated by analyzing a well‐investigated set of MDMA samples. Samples were prepared according to a harmonized extraction protocol to ensure the comparability of the chemical signatures. The nontargeted approach comprises preprocessing followed by analysis of variances as a fast filter algorithm for selection of a variable subset followed by partial least squares discriminant analysis for reduction to promising marker compounds for discrimination of the samples according to their chemical profile. Forty‐seven potential marker compounds were determined, covering most of the target impurities known from the harmonized one‐dimensional profiling as well as other compounds not previously elucidated.     

Driving Under the Influence of Synthetic Cannabinoid Receptor Agonist XLR‐11

The case of a 22‐year‐old male Caucasian driver is presented. He was involved in a traffic collision. At the roadside, he displayed blank stare and mellow speech with a barely audible voice. A DRE found low body temperature, rigid muscle tone, normal pulse, lack of horizontal and vertical gaze nystagmus, nonconvergence of the eyes, dilated pupil size, and normal Pupillary reaction to light. A standard toxicology DUID protocol was performed on the driver's whole blood including ELISA and GC‐MS drug screens with negative results. Additional drug screening was undertaken for bath salts and synthetic cannabinoid receptor agonists by LC‐MS/MS by a commercial laboratory and identified the synthetic cannabinoid receptor agonist XLR‐11 in the driver's blood. XLR‐11 was subsequently quantified at 1.34 ng/mL. This is the first documented case involving a driver operating a motor vehicle under the influence of the synthetic cannabinoid receptor agonist XLR‐11.     

Fatal intoxication involving 2-methyl AP-237

Novel synthetic opioids contribute considerably to the opioid epidemic, especially with the frequent emergence of structurally similar compounds. This case report describes a fatal intoxication involving 2-methyl AP-237. A 54-year-old Caucasian male was found deceased from an apparent drug overdose. A plastic container labeled “2MAP” and a cut straw were found in the decedent's backpack at the scene. A white substance found in the container tested positive for fentanyl by field testing. According to his medical history, the decedent was treated for a drug overdose 3 years prior to his death. With no diagnostic findings at autopsy, the case was submitted for toxicological analysis. An unknown substance was detected in peripheral blood and urine using gas chromatography with nitrogen phosphorous detection (GC-NPD). Further testing was conducted using gas chromatography–mass spectrometry (GC–MS) and liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) which confirmed the presence of 2-methyl AP-237 and potential metabolites in blood and urine. Quantitation by GC-NPD revealed concentrations of 2-methyl AP-237 in blood and urine at 480 ng/mL and 4200 ng/mL, respectively. The toxicological analysis also identified and quantitated alprazolam in the blood at 55 ng/mL. Additionally, the metabolism of 2-methyl AP-237 was investigated and three hydroxylated metabolites were identified in peripheral blood and urine. Limited literature is available for the detection and quantitation of 2-methyl AP-237 in postmortem specimens. Given the toxicological findings with unremarkable autopsy findings, this case is an example of a fatal intoxication involving 2-methyl AP-237.     

Rapid Identification of Synthetic Cannabinoids in Herbal Incenses with DART‐MS and NMR

The usage of herbal incenses containing synthetic cannabinoids has caused an increase in medical incidents and triggered legislations to ban these products throughout the world. Law enforcement agencies are experiencing sample backlogs due to the variety of the products and the addition of new and still‐legal compounds. In our study, proton nuclear magnetic resonance (NMR) spectroscopy was employed to promptly screen the synthetic cannabinoids after their rapid, direct detection on the herbs and in the powders by direct analysis in real time mass spectrometry (DART‐MS). A simple sample preparation protocol was employed on 50 mg of herbal sample matrices for quick NMR detection. Ten synthetic cannabinoids were discovered in fifteen herbal incenses. The combined DART‐MS and NMR methods can be used to quickly screen synthetic cannabinoids in powder and herbal samples, serving as a complementary approach to conventional GC‐MS or LC‐MS methods.