A Study of the Background Levels of Male DNA on Underpants Worn by Females

This study is the first to examine the background level of male DNA on underpants worn by females in the absence of sexual contact. Here, we examined 103 samples from the inside front of underpants from 85 female volunteers. Samples were examined for the presence of male DNA using NGM SElect and PowerPlex Y23 kits. Only five samples gave a “complete” Y-STR profile, even though 83.5% of our volunteers cohabited with a male. In all cases where a partner reference sample was available, the Y-STR profile matched the cohabiting partner. We have demonstrated that a Y-STR profile is not expected on the inside front of underpants worn by females after social contact alone. The results of this study are informative for evaluating the significance of a Y-STR profile on underpants in cases of alleged sexual assault.     

Sample Mining and Data Mining: Combined Real-Time and Retrospective Approaches for the Identification of Emerging Novel Psychoactive Substances

Novel psychoactive substances (NPS) are synthetic drugs that pose serious public health and safety concerns. A multitude of NPS have been identified in the United States, often implicated in forensic investigations. The most common and effective manner for identifying NPS is by use of mass spectrometry and the true utility lies within nontargeted acquisition techniques. During this study, a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) assay was developed, validated, and implemented for forensic toxicology testing. A SCIEX TripleTOF™ 5600 + with SWATH^® acquisition was used. Resulting data were compared against an extensive library database containing more than 800 compounds. The LC-QTOF-MS assay was applied to the reanalysis of biological sample extracts to discover emergent NPS. More than 3,000 sample extracts were analyzed, and more than 20 emerging NPS were detected for the first time. Among these were isopropyl-U-47700, 3,4-methylenedioxy-U-47700, fluorofuranylfentanyl, N-methyl norfentanyl, 2F-deschloroketamine, 3,4-methylenedioxy-alpha-PHP, eutylone, and N-ethyl hexedrone.     

Evaluation of Suspected Counterfeit Pharmaceutical Tablets Declared to Contain Controlled Substances Using Handheld Raman Spectrometers

This study describes the performance of handheld Raman devices for determining whether suspect pharmaceutical tablets declared to contain controlled substances were consistent with authentic (CWA) or not consistent with authentic (NCWA) tablets using a simple, rapid, field-friendly method capable of being used by nonexperts. Twenty-five authentic products and 84 known NCWA tablets were examined using three “parent” devices for a total of 327 analyses. On average, the parent devices yielded a true pass rate of 100%, a true fail rate of 98.4%, a false pass rate of 1.6%, and a false fail rate of 0%. The methods/libraries were then transferred to 13 identical “daughter” devices, which were used to examine 10 suspect finished dosage forms in duplicate (six known NCWA tablets and four authentic tablets) for a total of 260 measurements. On average, the daughter devices had a true pass rate of 100%, a true fail rate of 95.5%, a false pass rate of 4.5%, and a false fail rate of 0.0%. These data demonstrate that the parent–daughter electronic transfer method was successful, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices. The methods can then be used to (i) prioritize samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify active ingredients and (ii) help support the interdiction of dangerous tablets at ports of entry, thereby preventing them from reaching the supply chain.     

新冠肺炎疫情期间公安法医应当加强尸体甄别和个体防护

因鉴定体制特点,公安法医除参与尸体有关的现场勘查工作外,还需进行尸体检验工作。在此过程中,可能面对很多风险,受伤和中毒等事件时有发生。然而,国内公安法医对新冠肺炎等传染病流行期间死亡的尸体如何甄别进行尸体检验鉴定,对现场勘查及尸体检验工作的防护只有少量规定,且内容不够详尽。本文对法医在现场勘查中遇到的尸体及尸体检验中实验室建设、职业现状、风险评估及防范措施等进行了论述。最后,建议出台相关的制度规定等具体约束规范措施,以保障公安法医现场勘查及尸体检验工作的顺利进行,以解除基层鉴定机构和鉴定人的后顾之忧。     

法医精神病鉴定内容架构及评定要点解析

法医精神病鉴定在刑事、民事和行政三大诉讼领域中,以鉴定意见的证据形式发挥着重要作用。然而,与其重要性不相匹配的是,法医精神病鉴定学科发展尚不完善、专业发育尚不成熟,尚不能满足社会和民众的期盼和要求,甚至引发负面评价。为进一步促进法医精神病鉴定规范化、标准化建设。以法医精神病鉴定人的视角,结合法医精神病鉴定的内容架构,重点阐述法医精神病鉴定主要项目及其作用、评定要点,尤其聚焦刑事责任能力评定,阐明当前存在分歧和困难;简要介绍法医精神病鉴定人执业要求、法医精神病鉴定质量控制;以及简述法医精神病鉴定与临床精神医学实践的区别与联系。     

法医精神病鉴定质量控制对策研究

法医精神病鉴定是一种经验型或技能型鉴定类型,大多数鉴定项目只能依靠鉴定人的经验进行判断,质量控制更显重要。遗憾的是,目前该专业并未像其他法医类鉴定那样实行认证认可制度,质量控制手段不多。为有效保障鉴定质量,必须围绕鉴定意见形成过程的各个阶段或环节进行过程控制与监督,重点关注“人、机、料、法、环”等要素。为此,建议在该行业内逐步恢复认证认可制度,完善质量体系建设,运用好各种内外部质量控制方法,严格把关鉴定人准入,实行鉴定人执业分类管理、强化鉴定人执业能力考核,以规范行业鉴定活动,维护行业司法鉴定的公信力。     

红外光谱法用于安钠咖中咖啡因和苯甲酸钠快速定性和定量分析

目的 建立安钠咖样品中咖啡因和苯甲酸钠快速定性和定量分析的红外光谱方法.方法 采用高纯度咖啡因和苯甲酸钠混合制样的方法制备定性和定量建模样品,通过分析混合样品的红外光谱图,确定安钠咖样品中咖啡因和苯甲酸钠的特征吸收峰.采用偏最小二乘法(partial least squares,PLS)建立红外光谱定量模型.结果 通过...     

冠状病毒感染性疾病尸体检验相关病原学检测回顾与展望

冠状病毒曾经给世界带来两次严重的人类间大流行,包括严重急性呼吸综合征(severe acute re?spiratory syndrome,SARS)和中东呼吸综合征(Middle East respiratory syndrome,MERS),2019年岁末新型冠状病毒肺炎(coronavirus disease 2...     

A study of user data integrity during acquisition of Android devices

At the time of this writing, Android devices are widely used, and many studies considering methods of forensic acquisition of data from Android devices have been conducted. Similarly, a diverse collection of smartphone forensic tools has also been introduced. However, studies conducted thus far do not normally guarantee data integrity required for digital forensic investigations. Therefore, this work uses a previously proposed method of Android device acquisition utilizing ‘Recovery Mode’. This work evaluates Android Recovery Mode variables that potentially compromise data integrity at the time of data acquisition. Based on the conducted analysis, an Android data acquisition tool that ensures the integrity of acquired data is developed, which is demonstrated in a case study to test tool's ability to preserve data integrity.     

根据颈椎CT片特征指标进行同一认定的研究

目的选择颈椎CT片上的特征指标,建立逐步回归方程,探讨其在法医学同一认定中的应用价值。方法收集130名被检查者颈椎CT片各1张,70名被检查者不同次颈椎CT影像片各2张。选择并测量颈椎CT片上的13项指标值,分别计算被检查者随机分组后相同测量指标的组间差值,以及同一人不同次测量指标间的差值,运用二分类logistic逐步回归分析,建立各项指标的一元回归方程和多项指标的多元回归方程,并对方程进行盲测检验。结果建立的13个一元方程中同一认定的准确率在69.0%~90.4%之间;建立的4个多元回归方程的准确率在90.4%~96.7%之间,盲测准确率为100%。结论本文在CT片上选择的13项特征指标可以用于同一认定,使用时应尽可能选用多元指标以得到更准确的结果。