Quantitative Determination of Cannabinoids in Cannabis and Cannabis Products Using Ultra‐High‐Performance Supercritical Fluid Chromatography and Diode Array/Mass Spectrometric Detection

Ultra‐high‐performance supercritical fluid chromatography (UHPSFC ) is an efficient analytical technique and has not been fully employed for the analysis of cannabis. Here, a novel method was developed for the analysis of 30 cannabis plant extracts and preparations using UHPSFC /PDA ‐MS . Nine of the most abundant cannabinoids, viz . CBD , ?⁸‐THC , THCV , ?⁹‐THC , CBN , CBG , THCA ‐A, CBDA , and CBGA , were quantitatively determined (RSD s < 6.9%). Unlike GC methods, no derivatization or decarboxylation was required prior to UHPSFC analysis. The UHPSFC chromatographic separation of cannabinoids displayed an inverse elution order compared to UHPLC . Combining with PDA ‐MS , this orthogonality is valuable for discrimination of cannabinoids in complex matrices. The developed method was validated, and the quantification results were compared with a standard UHPLC method. The RSD s of these two methods were within ±13.0%. Finally, chemometric analysis including principal component analysis (PCA ) and partial least squares‐discriminant analysis (PLS ‐DA ) were used to differentiate between cannabis samples.     

Application of MALDI‐TOF MS for Estimating the Postmortem Interval in Rat Muscle Samples

Estimating the postmortem interval (PMI) is very important in the forensic sciences. Although many approaches have been used for estimating the PMI, accurate PMI calculations are still difficult. In this study, four Sprague Dawley (SD) rats were sacrificed by suffocation, and muscle samples were collected by dissection at various time intervals (0, 48, 96, and 144 h) after death. All samples were probed using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS) to obtain molecular images and data for principal component analysis (PCA). The results showed that the peaks at m/z 1511, 1543, 1564, 1586 clearly decreased in intensity from 0 to 144 h postmortem and that the time groups were separated from each other on the PCA score plot. The prediction model showed high recognition capability (95.93%) and cross‐validation (83.72%). Our work suggests that MALDI‐TOF MS can be used to determine the PMI.     

Effect of History and Context on Forensic Pathologist Interpretation of Photographs of Patterned Injury of the Skin

In a previous study, a survey‐based analysis of pathologist diagnoses of patterned injury was performed. Subjects were provided with photographs of “classic” injuries and asked to diagnose the lesion in the absence of history or context. There was a relatively low diagnostic consensus among respondents. A second survey suggested that the disparate answers were not due to a strong belief in different diagnoses, but instead reflected how the respondents dealt with ambiguity. A third survey was created that asked participants to evaluate patterned injuries of the skin, but provided history and contextual information. The addition of history and contextual information increased consensus from a median of 80% to 98% on a per‐question basis. Confidence increased from a median of 56%–92%. These results demonstrate the importance of history and context in medical diagnosis of patterned injuries of the skin.     

Feasibility of Canine Detection of Mass Storage Devices: A Study of Volatile Organic Compounds Emanating from Electronic Devices Using Solid Phase Microextraction

Detection of canines are well‐known to be valuable in the location of contraband, such as explosives or narcotics. More recently, canines have been trained and utilized in the detection of concealed mass storage devices that might contain evidence of illegal activity such as child pornography. To lay the analytical foundation for this detection work, research was carried out to determine the volatile organic compounds associated with mass storage devices (MSD) that could be used by trained canines for detection. Headspace analysis of a variety of electronic devices was performed using solid phase microextraction (SPME) with gas chromatography/mass spectrometry (GC/MS). Analyses found several volatile compounds common to SIM and SD cards, as well as USB drives, including 2‐propenenitrile, styrene, isophorone, hydroxycyclohexyl phenyl ketone, and 2‐furanmethanol, tetrahydro. Results indicated that mass storage devices do have a characteristic odor profile making detection with minimal false alerts feasible for trained canines.     

A Normative Approach to the Quistclose Trust

This is the first article to undertake a sustained analysis of normative justifications for the Quistclose trust. Whilst much of the existing writing on this topic has focused on the better classification of such trusts – for instance, whether they are express, resulting, constructive or sui generis – this article asks why the law should recognise a trust in addition to any underlying legal relationship. Four key justifications are addressed, based on respecting party intention, unconscionability, fairness, and the incentivisation of desirable transactions. It will be argued that: (i) there are difficulties with each of these justifications, although an intention‐focused explanation is probably the most convincing; and (ii) the existing law and commentary lacks coherence and consistency, as seen in the mismatch between normative and doctrinal analysis, and the failure to properly address the ramifications of the Quistclose trust during insolvency.     

视盘RNFL厚度改变与视野缺损的关系

目的探讨视网膜神经纤维层厚度与视野的关系及其在司法鉴定中的应用。方法采用GDx VCC和Octopus自动视野计对外伤视神经病变52例进行检查。按照视野有效值分组(组1-重伤组,组2-轻伤组,组3-轻微伤及以下组),统计其平均RNFL厚度,对各组的RNFL厚度进行方差分析;同时对平均RNFL厚度与视野指数(MD、MS、sLV)、视野有效值进行相关性及回归分析。结果组1的RNFL平均值36.300±8.456 95μm,组2的RNFL平均值53.647 4±15.453 06μm,组3的RNFL平均值60.903 6±9.535 14μm。通过方差分析,组1~3各组间差异显著,各组两两相比较差异显著。平均RNFL厚度与视野有效值、MS呈正相关(r=0.543、0.400,P0.05),平均RNFL厚度与MD、sLV呈负相关(r=-0.450、-0.440,P0.05)。平均RNFL厚度与视野有效值、MD、MS、sLV的直线回归方程分别为Y=0.967X+19.508、Y=0.095X-10.858、Y=0.175X+9.187、Y=-0.205X+20.215;二次项方程分别为Y=-0.037X~2+5.208X-93.795、Y=0.010X~2-1.325X+50.111、Y=-0.008X~2+1.103X-15.606、Y=0.004X~2-0.520X+22.232。结论 RNFL厚度检测具有客观评定视野的法医学价值,有望成为评估视野的一种客观、形态学新方法。     

应用膝关节MRI T_2加权脂肪抑制像推断活体年龄

目的探索膝关节MRI T2加权脂肪抑制像(T2-FS)在法医年龄推断中的应用价值,建立安全可靠的四川汉族年龄推断方法。方法收集膝关节MRI 324例(男性170例,女性154例),年龄范围为10~30岁。采用西门子1.5T磁共振仪摄片,MRI参数:T2-FS TSE序列,矢状位。将股骨远端、胫骨近端骨骺发育分为6个等级并赋分,分析各指标性别差异及年龄相关性,建立年龄推断回归模型。结果男女性股骨远端、胫骨近端MRI等级与年龄呈正相关性,股骨远端与年龄的相关性男性0.687,女性0.661;胫骨近端与年龄的相关性男性0.684,女性0.488。股骨远端骨骺完全闭合,骺线消失的最小年龄男性18.42岁,女性19.36岁;胫骨近端男性骺线消失的最小年龄为16.93岁,女性为14.68岁。股骨远端等级1~3、5、6和胫骨近端等级1~3、5年龄分布性别差异不显著。分别建立男女年龄推断模型,男性年龄推断平均绝对误差(MAD)=2.90岁;女性年龄推断MAD=3.30岁。结论膝关节MRI T2-FS影像可作为活体年龄推断的指标之一,股骨远端等级6可作为判断18岁的指标之一。     

HPLC-MS/MS法快速检测人体血液中的夹竹桃毒素

目的采用高效液相色谱-串联质谱法(HPLC-MS/MS)检测人体血液中夹竹桃苷、夹竹桃苷乙。方法采用乙腈沉淀蛋白法处理血液,HPLC-MS/MS法检测,采用MRM记录方式,保留时间和定性离子对定性,标准曲线法定量。结果夹竹桃苷、夹竹桃苷乙的检测限均在0.5ng/m L,线性范围在1ng/m L~1mg/m L,回收率为75.2%~95.7%。结论本方法操作简便,灵敏度高,可应用于中毒案件中人体血液中两种夹竹桃毒素(夹竹桃苷和夹竹桃苷乙)的快速检测。     

20723例亲子鉴定中19个STR基因座的突变分析

目的观察并分析肯定亲权关系的案件,探索STR基因座的突变规律。方法采用Goldeneye 20A试剂盒对20723例肯定亲权关系的案件筛选等位基因突变事件,统计各基因座的突变率和突变等位基因的来源、片段大小、突变步数及重复单位的增加或减少情况,分析突变相关因素的特点。结果 19个STR基因座共发现548例突变,观察到557个突变事件,基因座的突变率为0.07‰~2.23‰。父系突变与母系突变的比例为3.06∶1。突变以一步突变为主,增加与减少重复单位的情况相当;二步以上(含二步)突变更易出现重复单位减少。突变主要发生于中等位基因,重复单位增减比例相当,长等位基因突变中重复单位减少显著多于增加。父系突变出现重复单位增加与减少的比例相当,母系突变重复单位减少较增加多见。结论各基因座的突变率差异具有统计学意义,当出现1~2个基因座不符合遗传规律时,应当加测其他检测系统,并结合突变基因座的信息计算PI值,以进一步明确鉴定意见。