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.     

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.     

China's stance on the Google/Motorola merger: Implications for competition in intellectual property-intensive sectors

China's merger enforcement agency approved the Google/Motorola merger with conditions. This pattern of approval is not in full accordance with that in other jurisdictions, including the United States and the European Union, which made unconditional approvals. This contradiction attracted ample criticism; some critics believe that China's policy is designed to protect domestic industry. In investigating the Chinese merger agency's decision and the basis for its decision making, this article finds that much of the criticism is groundless and misleading because the critics have failed to incorporate all elements of the global value chain of mobile intelligent terminals into their analyses. The investigation also shows that, although the decision makers are less experienced, their decisions are based on Chinese competition law and market realities. It is important for international firms to be aware of this pattern in merger analysis.     

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。     

Understanding Parental Gatekeeping in Families with a Special Needs Child

Supporting the positive development of a special needs child is especially challenging when parents have separated or divorced. Invariably, there is an increased need for collaborative co‐parenting wherein information is shared and intervention plans can be implemented effectively. In this article, the evolving literature on parental gatekeeping is applied to families with special needs children, as it offers a useful model for understanding the strengths and liabilities of co‐parenting relationships. We describe some of the typical and unique gatekeeping dynamics that occur when children suffer from developmental, physical, and/or psychiatric syndromes that require specific treatment and specialized parenting skills. Examples of both restrictive and facilitative gatekeeping are described as they manifest in these families. Implications for decision making are also discussed.     

高压架空输电线走廊周边楼房电磁环境研究

对城乡交界处220kV/110kV高压架空输电线走廊模式发生变化后的三种架设形式进行了测试分析。结果表明,220kV/110kV四回路杆塔形式对周边楼房室内外环境影响较大,当两者相距60m以外时,楼房室内外工频电磁场环境将有较大改善;居民楼建筑结构对工频电磁场有一定衰减作用,其中工频电场衰减较大,工频磁场衰减较小。建议适当控制高压架空输电线走廊与居民区的距离。     

甲卡西酮对大鼠血浆代谢谱变化研究

目的 应用代谢组学技术研究腹腔注射甲卡西酮大鼠血浆代谢谱的变化,筛选出可用于甲卡西酮吸毒法医学鉴定的入体生物标志物.方法 SD大鼠随机分成低剂量甲卡西酮组(腹腔注射甲卡西酮溶液3mg/kg)、中剂量甲卡西酮组(腹腔注射甲卡西酮溶液12mg/kg)和对照组(腹腔注射等量生理盐水),注射3min后收集大鼠眼眶血,应用超高效...     

SPREADING THE WEALTH: THE EFFECT OF THE DISTRIBUTION OF INCOME AND RACE/ETHNICITY ACROSS HOUSEHOLDS AND NEIGHBORHOODS ON CITY CRIME TRAJECTORIES*

This study tests the effect of the composition and distribution of economic resources and race/ethnicity in cities, as well as how they are geographically distributed within these cities, on crime rates during a 30‐year period. Using data on 352 cities from 1970 to 2000 in metropolitan areas that experienced a large growth in population after World War II, this study theorizes that the effect of racial/ethnic or economic segregation on crime is stronger in cities in which race/ethnicity or income are more salient (because of greater heterogeneity or inequality). We test and find that higher levels of segregation in cities with high levels of racial/ethnic heterogeneity lead to particularly high overall levels of the types of crime studied here (aggravated assaults, robberies, burglaries, and motor vehicle thefts). Similarly, higher levels of economic segregation lead to much higher levels of crime in cities with higher levels of inequality.     

Laser desorption/ionization time-of-flight mass spectrometry of triacylglycerols and other components in fingermark samples

The chemical composition of fingermarks could potentially be important for determining investigative leads, placing individuals at the time of a crime, and has applications as biomarkers of disease. Fingermark samples containing triacylglycerols (TAGs) and other components were analyzed using laser desorption/ionization (LDI) time-of-flight mass spectrometry (TOF MS). Only LDI appeared to be useful for this application while conventional matrix-assisted LDI-TOF MS was not. Tandem MS was used to identify/confirm selected TAGs. A limited gender comparison, based on a simple t-distribution and peaks intensities, indicated that two TAGs showed gender specificity at the 95% confidence level and two others at 97.5% confidence. Because gender-related TAGs differences were most often close to the standard deviation of the measurements, the majority of the TAGs showed no gender specificity. Thus, LDI-TOF MS is not a reliable indicator of gender based on fingermark analysis. Cosmetic ingredients present in some samples were identified.