A novel method for cyanide quantification in human whole blood using ion chromatography with amperometric detection and its application to cyanide intoxication cases

Cyanide is a highly toxic agent that has been frequently used for suicide in South Korea. It is also used in various industrial fields, such as metal plating, in which many accidental cyanide intoxications have occurred. To overcome the disadvantages of conventional cyanide analysis methods, a simple and fast method for the analysis of cyanide in whole blood using ion chromatography (IC) with amperometric detection was developed in this study. Whole blood samples were deproteinized, diluted, and analyzed using an IC–amperometric detection system. The limits of detection and quantitation were 0.1 and 0.2 mg/L, respectively. The method showed good linearity in the range of 0.2 to 50 mg/L with R² > 0.99. The intra- and inter-assay precision and accuracy values were <10%. The established method was successfully applied to analyze whole blood samples from three cyanide intoxication cases.     

Observer determination of the make,model, and year of questioned vehicles

Often, criminal acts involving a vehicle are caught on digital video surveillance systems. While potentially useful for an investigation, the recording conditions are typically less than optimal for the extraction of key information for the identification of the perpetrator, such as a license plate. Providing the make, model and year of a questioned vehicle is a common request for examiners, to narrow the field of potential suspect vehicles. This study seeks to compare the performance of a nonpeer-reviewed make, model, and year determination between two separate groups, specifically, trained forensic image examiners and nontrained individuals. Results show that even with varied image capture conditions and quality, the trained forensic image examiners more correctly and completely identified the test group of questioned vehicles make, model, and year.     

Postmortem Computed Tomography in Firearm Homicides: A Retrospective Case Series,

Postmortem computed tomography (PMCT) is integrated into the evaluation of decedents in several American medical examiner offices and medicolegal death investigative centers in many other countries. We retrospectively investigated the value of PMCT in a series of firearm homicide cases from a statewide centralized medical examiner’s office that occurred during 2016. Autopsies were performed or supervised by board-certified forensic pathologists who reviewed the PMCT scans prior to autopsy. PMCT scans were re-evaluated by a forensic radiologist blinded to the autopsy findings and scored by body region (head–neck, thoracoabdominal, and extremities). Injury discrepancies were scored using a modified Goldman classification and analyzed with McNemar’s test. We included 60 males and 20 females (median age 31 years, range 3–73). Based on PMCT, 56 (79.1%) cases had injuries relevant to the cause of death in a single body region (24 head–neck region, 32 thoracoabdominal region). Out of these 56 cases, 9 had a missed major diagnosis by PMCT outside that region, including 6 extremity injuries visible during standard external examination. Yet all had evident lethal firearm injury. We showed that PMCT identifies major firearm injuries in homicide victims and excludes injuries related to the cause of death in other regions when a single body region is injured. Although PMCT has a known limited sensitivity for soft tissue and vascular pathology, it can be combined with external examination to potentially reduce or focus dissections in some of these cases depending on the circumstances and medicolegal needs.     

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.     

骨龄自动化评估的研究进展

骨龄是反映人体生长发育的一项重要指标,能够较为客观地反映个体生长发育水平及成熟度。传统的人工骨龄评估通常是将左手腕X线片与参考标准进行比较,从而获得相应的骨龄值,该方法既耗时又存在观察者间的差异。近年来,随着计算机科学的不断发展,促使骨龄评估开始由传统的人工评估向自动化评估转变。虽然骨龄自动化评估的研究已相当多,但大部分仍处于实验阶段。本文综述了近年来国内外学者在骨龄自动化评估方面的相关研究与进展,以期为相关研究人员提供参考与研究思路。     

比色法测定人参中人参总皂苷的含量

目的：建立人参中人参总皂苷的含量测定方法。方法：采用比色法测定。结果：比色法测定的线性范围为15．0～75．0μg，相关系数γ=0．9997；平均回收率为100．61％，RSD为1．51％(n=6)。结论：本法简便、准确、灵敏度高、重复性好，可用于人参药材及含人参制剂的含量测定。     

百草枯中毒分析检测方法的研究进展

本文介绍了最近20年来国内外有关生物检材中百草枯的提取、净化及定性定量分析检测方法的研究进展,从而为进一步研究百草枯中毒的分析检验方法提供参考。     

High performance liquid chromatographic determination of alcohols with reference to body distribution of methanol

A method has been developed on reverse phase high performance liquid chromatography for simultaneous determination of methyl, ethyl and isopropyl alcohols under refractive index detection using pure water as the mobile phase. A good separation has been achieved between these alcohols. Detector response was linear with a detection limit of 5 mg/100 ml. Recovery studies were performed by adding known amounts of methyl and ethyl alcohols to blood, lung and liver within the range 80–90%. The reproducibility of the results was always >90%. The quantitative distribution of methyl alcohol in postmortem body tissues and fluids has been reported in three cases of poisoning.     

契约的正义——读《法律、立法与自由》札记

通过对哈耶克自由主义法律理论的解读,笔者提出了一种理解契约正义的思想理路。即在自由主义的视域中,自由是正义的核心价值,正义实为对人的意志本身的评价,而不能从行为结果衡量,因此,不管缔约人追求的具体目的如何,我们应以缔约人意志的自由状态作为评价契约是否符合正义的基本标准;普遍的契约自由的实现有赖于法律的保障,缔约意志实为其内在动机与外在法律互动的结果,唯有以契约法为核心的私法具有保障契约自由普遍实现的功能品性,因此,所谓契约正义实为缔约人依私法自由缔约的契约本身。     

欧盟反倾销调查不同阶段关于产业损害认定的法律标准及证据规则

根据欧盟现有的反倾销立法及其实践,欧盟反倾销产业损害认定能否成立大致可以分成立案审查阶段、初裁前调查阶段、终裁前后续调查阶段和复审阶段等四个阶段.这四个阶段中,欧盟反倾销调查机构关于损害认定的法律标准的侧重点各不相同,而且在利害关系方证据材料的要求方面各具不同特点.欧盟产业损害调查各阶段法律标准和证据规则侧重点不同的做法并没有违反WTO《反倾销协定》之原则和精神,欧盟反倾销调查各阶段产业损害认定采用不同标准的做法值得我国借鉴.