Identification of furosemide in hair in a post‐mortem case by UHPLC‐MS/MS with guidance on interpretation

Testing for drugs in hair raises several difficulties. Among them is the interpretation of the final concentration(s). In a post‐mortem case, analyses revealed the presence of furosemide (12 ng/mL) in femoral blood, although it was not part of the victim's treatment. The prosecutor requested our laboratory to undertake an additional analysis in hair to obtain information about the use of furosemide. A specific method was therefore developed and validated to identify and quantify furosemide in hair by UHPLC‐MS/MS. After decontamination of 30 mg of hair, incubation in acidic condition, extraction with ethyl acetate, the samples were analyzed by UHPLC‐MS/MS. Furosemide was found in the victim's hair at 225 pg/mg. However, it was not possible to interpret this concentration due to the absence of data in the literature. Therefore, the authors performed a controlled study in two parts. In order to establish the basis of interpretation, several volunteers were tested (four after a single 20 mg administration and twenty‐four under daily treatment). The first part indicated that a single dose is not detectable in hair using our method. The second part demonstrated concentrations ranging from 5 to 1110 pg/mg with no correlation between dosage and hair concentrations. The decedent's hair result was interpreted as repeated exposures. In the case of furosemide analysis, hair can provide information about its presence but cannot give information about dosage or frequency of use.     

Characterization and differentiation of aluminum powders used in improvised explosive devices – Part 1: Proof of concept of the utility of particle micromorphometry

Aluminum (Al) powders are commonly used in improvised explosive devices as metallic fuels, a component of explosive mixtures. These powders can be obtained readily from industrial‐scale and consumer products, and produced using unsophisticated “kitchen chemistry” techniques. This research demonstrates the potential of automated particle micromorphometry for comparisons between known source and questioned Al powders recovered from IEDs, as well as for insight into the method of Al powder manufacture. Al powder samples were obtained from legitimate manufacturers, and 56 samples were produced “in‐house” from Al‐containing spray paints and ball‐milled Al foils. Transmitted light microscope images of Al powder particles were acquired using an automated stage with automated z‐focus; 17 size and shape parameters were measured for all particles. Approximately 37,000–2,500,000 particles/sample were analyzed using an open‐source statistical package with customized code. Dimensionality reduction was required for processing the large datasets: eight of the 17 measured variables were selected based on inspection of the correlation matrix. Data from four subsamples from each of the 56 samples produced using “in‐house” methods were analyzed using ANOVA to assess the within‐ and between‐sample variation. High within‐sample variation was noted; however, ANOVA and post‐hoc Tukey's honestly significant difference (HSD) tests demonstrated that the between‐sample variation was substantially larger than the within‐sample variation. Each sample could be differentiated from all other samples in the test set. Future experiments will focus on ways to reduce the within‐sample variation, and additional statistical and microanalytical methods to classify sources and confidently constrain the method of Al powder manufacture.     

Firearm examination: Examiner judgments and computer‐based comparisons

Forensic firearm examination provides the court of law with information about the source of fired cartridge cases. We assessed the validity of source decisions of a computer‐based method and of 73 firearm examiners who compared breechface and firing pin impressions of 48 comparison sets. We also compared the computer‐based method's comparison scores with the examiners' degree‐of‐support judgments and assessed the validity of the latter. The true‐positive rate (sensitivity) and true‐negative rate (specificity) of the computer‐based method (for the comparison of both the breechface and firing pin impressions) were 94.4% and at least 91.7%, respectively. For the examiners, the true‐positive rate was at least 95.3% and the true‐negative rate was at least 86.2%. The validity of the source decisions improved when the evaluations of breechface and firing pin impressions were combined and for the examiners also when the perceived difficulty of the comparison decreased. The examiners were reluctant to provide source decisions for "difficult" comparisons even though their source decisions were mostly correct. The correlation between the computer‐based method's comparison scores and the examiners' degree‐of‐support judgments was low for the same‐source comparisons to negligible for the different‐source comparisons. Combining the outcomes of computer‐based methods with the judgments of examiners could increase the validity of firearm examinations. The examiners' numerical degree‐of‐support judgments for their source decisions were not well‐calibrated and showed clear signs of overconfidence. We suggest studying the merits of performance feedback to calibrate these judgments.     

Bruise dating using deep learning

The bruise dating can have important medicolegal implications in family violence and violence against women cases. However, studies show that the medical specialist has 50% accuracy in classifying a bruise by age, mainly due to the variability of the images and the color of the bruise. This research proposes a model, based on deep convolutional neural networks, for bruise dating using only images, by age ranges, ranging from 0–2 days to 17–30 days, and images of healthy skin. A 2140 experimental bruise photograph dataset was constructed, for which a data capture protocol and a preprocessing procedure are proposed. Similarly, 20 classification models were trained with the Inception V3, Resnet50, MobileNet, and MnasNet architectures, where combinations of learning transfer, cross‐validation, and data augmentation were used. Numerical experiments show that classification models based on MnasNet have better results, reaching 97.00% precision and sensitivity, and 99.50% specificity, exceeding 40% precision reported in the literature. Also, it was observed that the precision of the model decreases with the age of the bruise.     

Integration without Reunification

The United States, the third actor in what is still too often perceived as a bilateral and 'internal' dispute, will likely continue to prevent the direst of scenarios from taking place in cross-Strait relations: Taiwan independence, Taiwan's forced absorption by China, or even war. This outside constraint as well as the rapid development of multiple relations across the Strait hopefully will narrow the options available to Beijing and Taipei in the future. Nevertheless, while economic integration and cultural affinities may ease the development of a form of political integration, a formal unification that would solve the sovereignty issue and result in the dissolution of the Republic of China seems unlikely, even after the People's Republic of China democratises. More likely, a particular formula recognising that Taiwan is part of China but not 'mainland China' may be worked out by the two governments when Beijing eventually finds it to be both an interest and politically acceptable to formalise the 'integration without reunification' situation.     

“同舟共济”与适应性变革:经济增长、权力转移及中美关系

由于经济增长的差异,新兴市场日益崛起,亚太地区日益崛起,其中中国崛起尤为瞩目。纵观权力转移历史、理论与现实,中国积极寻求融入当前美国主导的国际制度安排,在战略上是正确的,中国成为这一制度的得利较多者,也是满意者和维护者。因此综合长期战略和当前金融危机冲击下的策略,除了积极推动美国对当前制度进行适应性变革外,对于美国目前的困境,中国应该量力积极帮助,共同促进全球经济早日复苏和全球善治,与美国"同舟共济"符合中国战略利益,中国需要战略规划;同时,需要面向未来,准备好美国经济复苏后的策略变化。美国凭其发达的金融业在全球财富再分配中占领制高点,金融业的发展意味着可以在财富的再分配中获得竞争优势,因此中国需要大力发展现代金融业。     

静态资源关系观及其批判

最近几十年里,关于人类资源关系的辩论越来越激烈。学者们大致形成了两个对立的流派。资源悲观主义认为,人类资源关系是零和的,一个人群消耗的资源增加了,其他群体可能得到的资源就会减少。因此,随着资源越来越匮乏,人类资源冲突会愈演愈烈。资源乐观主义认为,人类资源关系是非零和的,资源冲突能够避免。悲观主义和乐观主义尽管尖锐对立,但有共同缺陷——都是静态理论,对资源关系的解释力有限。对此,本文提出了动态的资源关系理论,能够更好地解释人类资源关系。     

Intimate Partner Violence and Psychological Distress among Young Couples: Analysis of the Moderating Effect of Social Support

Young adults are more likely to experience intimate partner violence (IPV) than older adults. Little is known about the effect of confiding to others about sustained violence on the mental health of victims. The objective of this study was to explore the links between IPV, help-seeking behaviors and psychological distress by gender in a sample of 233 young couples.Our results indicate the frequency of sustained psychological violence, but not physical violence, was positively associated to distress. For women, seeking help from a greater number of confidents moderated the association between violence and psychological distress. For men, results showed that frequencies of physical and psychological violence were both positively linked to distress. However, unlike women, social support had no buffering effect on men’s distress. These findings increase our understanding of the effects of social support on young adults’ distress following episodes of IPV.     

人力资源管理思想:三个里程碑及其在中国的升华

人力资源管理实践历程中三个标志性实验成果昭示了人力资源管理思想演变的客观规律,是人力资源管理思想嬗变过程中的三大里程碑。科学管理实验使人力资源管理从自发管理走向自觉管理、科学管理和制度管理;霍桑实验系统发现了提高生产效率的社会心理因素,使人力资源管理从技术管理走向社会管理、行为管理和心理管理;职业生涯实验显示员工职业发展也是现代企业管理目标,现代企业目标和员工职业发展目标共存共长。三次实验的思想脉络、理论构造、功能机制有机对接、联动传承并推向纵深,成为人力资源管理历史上三个具有划时代意义的丰碑。科学人才观提出的"以人为本"的思想和理念是人力资源管理思想在当代中国的发展和升华。