Identification of acepromazine in hair: an illustration of the difficulties encountered in investigating drug-facilitated crimes

After a drug-facilitated sexual assault (DFSA), a woman was found in a drowsy state at home. She remembered having drunk an unknown beverage by the accused. Blood samples (collected 8 hours after the DFSA), two glasses, and a teaspoon seized by the police were analyzed. Acepromazine, a phenothiazine tranquilizer used in human and veterinary medicine, was detected in the residue of one of the glasses. In spite of acepromazine absence in the victim's blood, the possible use of acepromazine in the DFSA was reported to the police. Two weeks later, a suspect admitted having orally administered acepromazine to the victim. Using a liquid chromatography-tandem mass spectrometry method, this compound was subsequently detected (31 pg/mg) in a sample of the victim's hair collected a month and a half after the DFSA. A potential short elimination half-life in humans and/or the well-known in vitro degradation of acepromazine could explain the negative blood result. DFSA toxicological investigations are challenging and can be complicated when a rather unusual substance is concerned. In particular, special care should be taken when interpreting the results, taking into account elimination and/or instability data, when available.     

Classification and individualization of black ballpoint pen inks using principal component analysis of UV-vis absorption spectra

The technique of principal component analysis has been applied to the UV-vis spectra of inks obtained from a wide range of black ballpoint pens available in the UK market. Both the pen ink and material extracted from the ink line on paper have been examined. Here, principal component analysis characterised each spectrum within a group through the numerical loadings attached to the first few principal components. Analysis of the spectra from multiple measurements on the same brand of pen showed excellent reproducibility and clear discrimination between inks that was supported by statistical analysis. Indeed it was possible to discriminate between the pen ink and the ink line from all brands examined in this way, suggesting that the solvent extraction process may have an influence on these results. For the complete set of 25 pens, interpretation of the loadings for the first few principal components showed that both the pen inks and the extracted ink lines may be classified in an objective manner and in agreement with the results of parallel thin layer chromatography studies. Within each class almost all inks could be individualised. Further work has shown that principal component analysis may be used to identify a particular ink from a database of reference UV-vis spectra and a strategy for developing this approach is suggested.     

A Bayesian approach to estimate skeletal age-at-death utilizing dental wear

In the forensic context, teeth are often recovered in mass disasters, armed conflicts, and mass graves associated with human rights violations. Therefore, for victim identification, techniques utilizing the dentition to estimate the first parameters of identity (e.g., age) can be critical. This analysis was undertaken to apply a Bayesian statistical method, transition analysis, based on the Gompertz-Makeham (GM) hazard model, to estimate individual ages-at-death for Balkan populations utilizing dental wear. Dental wear phases were scored following Smith's eight-phase ordinal scoring method and chart. To estimate age, probability density functions for the posterior distributions of age for each tooth phase are calculated. Transition analysis was utilized to generate a mean age-of-transition from one dental wear phase to the next. The age estimates are based on the calculated age distribution from the GM hazard analysis and the ages-of-transition. To estimate the age-at-death for an individual, the highest posterior density region for each phase is calculated. By using a Bayesian statistical approach to estimate age, the population's age distribution is taken into account. Therefore, the age estimates are reliable for the Balkan populations, regardless of population or sex differences. The results showed that a vast amount of interpersonal variation in dental wear exists within the current sample and that this method may be most useful for classifying unknown individuals into broad age cohorts rather than small age ranges.     

Assessing the (eco)macroeconomic performance index of India: A data envelopment analysis approach

The prime objective of this article is to construct a robust macroeconomic performance (MEP) index of the Indian economy using the data envelopment analysis (DEA) approach. Seven major macro indicators, namely, economic growth, employment rate, terms of trade, inflation rate, fiscal deficit, pollution, and climate change are used to compute MEP and Eco‐MEP indices of the Indian economy from 1980–1981 to 2018–2019. Overall, both the MEP and Eco‐MEP index scores have quite similar best performing years worst performing years, and have also captured the major events that affected adversely the Indian economy during the past decades. The trend in the overall performance of the Indian economy was better in the 1980s and the 1990s but has deteriorated since 2000. The autoregressive distributed lag bounds testing approaches to cointegration methods are used to test the robustness/utility of these indices. The estimated results show that MEP and Eco‐MEP have a positive impact on private investment, foreign investment inflows, foreign direct investment, and a negative effect on the current account deficit. Hence, the suggested composite MEP index is stable, robust and truly captures the economic performance of India. The constructed MEP composite index may be used by foreign investors, rating agencies, private investors, and policymakers for their planning and decision‐making processes.     

A solid-phase microextraction method for the detection of ignitable liquids in fire debris

A solid-phase microextraction (SPME) procedure involving direct contact between the SPME fibers and the solid matrix and subsequent gas chromatography/mass spectrometric analysis for the detection of accelerants in fire debris is described. The extraction performances of six fibers (100 mum polydimethylsiloxane, 65 mum polydimethylsiloxane-divinylbenzene, 85 mum polyacrylate, 85 mum carboxen-polydimethylsiloxane, 70 mum Carbowax-divinylbenzene, and 50/30 mum divinylbenzene-Carboxen-polydimethylsiloxane) were investigated by directly immersing the fibers into gasoline, kerosene, and diesel fuel. For simulated fire debris, in the direct contact extraction method, the SPME fiber was kept in contact with the fire debris matrix during extraction by penetrating plastic bags wrapping the sample. This method gave comparable results to the headspace SPME method in the extraction of gasoline and kerosene, and gave an improved recovery of low-volatile components in the extraction of diesel fuel from fire debris. The results demonstrate that this procedure is suitable as a simple and rapid screening method for detecting ignitable liquids in fire debris packed in plastic bags.     

Hair analysis to document non-fatal pesticide intoxication cases

We reported two non-fatal cases of intoxication with pesticides namely alachlor and carbofuran. Hair stand samples were collected from two men approximately 1 year after alachlor intoxication for case 1, and 14 days after the last exposure for case 2. Hair analysis was performed using a liquid chromatography-tandem mass spectrometry method. In case 1, alachlor was detected in the 5 analysed hair segments (concentrations between 12 and 136 pg/mg) and its metabolites were not detected. In case 2, carbofuran and its main metabolite (3-hydroxycarbofuran) were detected in the hair strand (global analysis) at the concentrations of 207 and 164 pg/mg, respectively. However, additional data are required in order to interpret such results.     

Application of discriminant analysis to differentiate between incorporation of cocaine and its congeners into hair and contamination

The requirement to differentiate between incorporation and external contamination of drugs into hair is undisputed, in particular when dealing with compounds which are administered by sniffing or inhalation (e.g. cocaine). With the aim of making this discrimination, hair samples from cocaine (COC) users (group IN) and seized cocaine samples (group OUT) were compared regarding the parameters benzoylecgonine (BZE), ecgonine methyl ester (EME), ecgonine (ECG), anhydroecgonine methyl ester (AEME), cocaethylene (CE) and norcocaine (NCOC). Since most of these compounds may be minor by-products of COC or be formed by biotransformation or chemical degradation, the stability of each substance was carefully examined. COC was found to be converted into significant amounts of BZE, EME and ECG even under mild extraction conditions, while traces of NCOC proved to be a ubiquitous by-product of COC. Cocaine positive hairs and seized cocaine samples (diluted to relevant concentrations) were equally preprocessed and analyzed by LC-MS-MS. Out of the metabolites listed above, NCOC, CE and AEME (each normalised to COC) were significantly increased in the incorporation group (i.e. hair samples from cocaine users). Based on this approach, a statistical discriminant analysis enabled us to make a prediction (and estimation of uncertainty) for each cocaine positive hair sample as to its likelihood of belonging to the group of cocaine users or of being contaminated.     

退休政策的经济学分析及调整

退休政策通过影响劳动力的投入和养老负担对社会产出和就业人口、退休人口的福利水平产生影响，因此要对退休政策进行调整须进行较为充分的经济论证。研究对单人经济的退休年龄分析显示：存在一个基于个人一生效用最大化的“最佳”退休年龄，可合理平衡一生总产出和退休后的休闲。同理，一个多人经济社会也存在一个平均的“最佳”退休年龄。研究的结论如下：现有的退休年龄政策背景下，中国将面临日益沉重的养老负担，说明中国的退休年龄政策亟须调整；延迟退休年龄至少在长期对就业无负面影响，且可增加GDP:将暂时多余的社保基金用于金融投资无助于社会养老负担的缓解，养老金空账运行并无问题。为完善中国的退休政策，研究提出适时延长退休年龄、提高养老金标准和降低养老保险费率、对职工上缴的养老保险实施记账等建议。     

模糊立法语言的语义学分析

法律以语言文字为载体。尽管法律人竭力为法律概念设定边界,但是大部分法律概念的内涵或外延依然是模糊的。在法律的创制过程中,合理使用模糊语言不但不会损害法律的明确性,相反倒可能有助于在不确定中寻求到确定性。