人离体肝组织胺类产生与死亡时间和环境温度的关系

目的探讨在不同环境温度下,人离体肝组织中有机胺类产生量随死亡时间变化的规律,为某些碎尸案的死亡时间推断提供参考资料。方法应用高效液相色谱仪外标法,动态检测人离体肝组织中组胺、腐胺、尸胺和未腐败氨基酸含量。结果在8℃、15℃、23℃和32℃环境下,有机胺类产生量分别于人死后肝脏即刻离体69h、54h、40h和33h趋于最大值,并且在到达峰值之前,各温度组离体肝组织中有机胺类生成量均与死亡时间成正比关系。结论人离体肝组织中有机胺类产生量与死亡时间和环境温度在一定范围内均呈正相关。     

《23—6Ⅱ》《快干RCP》锈转化保护剂的研究

《23-6带锈防锈剂》和《快干RCP锈转化保护剂》均是新型的钢铁表面处理剂和防蚀剂,它能直接涂盖于钢铁表面而不需预先除锈,它能于氧化铁(铁锈)互相作用、生成稳定的螯合物,使铁锈转化为稳定、坚实的覆盖层,对钢铁构件起保护作用。《23-6》曾获湖北省重大科技成果二等奖和国家科技进步二等奖,在此基础上研制的《快干RCP》已通过省级鉴定。经中国专利局文献检索证明,“国内外未见完全相同产品,经中国船检局认可颁发船用产品证书”。《快干RCP锈转化保护剂》是继《23-6Ⅱ带锈防锈剂》之后,研制出的新产品。     

A comparison of three automated DNA purification methods in Forensic casework

Manual Chelex^®-100 and organic extractions (phenol/chloroform) are used as routine methods at the Swedish National Laboratory of Forensic Science, SKL. The aim of this study was to find an automated DNA purification system to replace the organic method. The following methods were evaluated and compared to each other and to the organic method used routinely; BioRobot^® EZ1 with EZ1 DNA Investigator Kit and Card (Qiagen), iPrep™ Purification Instrument with iPrep™ ChargeSwitch^® Forensic Kit and Card (Invitrogen), Magnatrix™ 1200 Workstation with the Magnatrix™ gDNA Blood Kit Forensic and two different protocols; Forensic protocol A and B (Magnetic Biosolutions). Blood on fats, cotton swabs, moist snuff, paper towels and leather, post-mortem blood and muscle tissue were extracted with the different methods. DNA concentration and quality of the electropherograms were examined. Individual comparisons between the four extraction methods showed that iPrep™ and Magnatrix™ 1200 gave significantly lower mean quantities compared to BioRobot^® EZ1 and the organic extraction method (p < 0.05). There were no significant differences between the latter two. BioRobot^® EZ1 generated the best results and is in the process of being validated for routine analysis at SKL.     

Moistened hands do not necessarily allude to high quality fingerprints: the relationship between palmar moisture and fingerprint donorship

We explored the quality distribution of ninhydrin-developed prints on A4 bond paper in two groups of individuals, in Israel and in India. While the quality distributions of the developed marks in both countries had some dissimilarities, both groups showed the expected bell-shape distribution, with the majority of the donors belonging to the central zone, defined as "average" or "good." Attempt was made to correlate between a physiological feature, palmar moisture, and the fingerprint donorship. As a rule, high fingermark quality could be associated with sweating hands, but there were individuals with moist palms whose fingermarks had a low score and vice versa. This finding supports the logical but hitherto unproven assumption that besides the amount of palmar sweat, the other physiological factor governing the prints' quality is the total amount of substrate, amino acids in this case, in the latent deposits, which depends on the substrate concentration in the sweat.     

核酸及蛋白质在死亡时间推断中的应用

死亡时间(postmortem interval,PMI)推断一直是法医学研究的重点与难点.机体死亡后,组织细胞发生自溶,核酸等大分子物质发生降解,其中DNA含量呈逐渐下降趋势,与PMI具有一定的线性关系,管家基因β-actin、GAPDH mRNA具有一定的稳定性,也可作为内参照进行PMI推测.本文综述了目前DNA、...     

Waxing grave about adipocere: soft tissue change in an aquatic context

When postmortem environmental conditions are "just right," according to the "Goldilocks Phenomenon," soft tissues (and associated fatty acids) are converted into and preserved as adipocere. To better understand this conversion process and the development of adipocere three human cadavers were immersed in outside, water-filled pits for over 3 months to observe adipocere formation in an underwater context simulating actual field conditions. Recordings of environmental conditions showed that temperatures were between 21 degrees C and 45 degrees C, a range sufficient for the growth of Clostridium perfringens. Chemical analysis of liquid and tissue samples revealed an increase in palmitic acid and decrease in oleic acid. This study tracked the remarkable gross morphological changes that can occur in human bodies subjected to an aquatic postmortem environment. The results support the "Goldilocks Phenomenon" and substantiate previous findings that the presence of bacteria and water is crucial for adipocere to form.     

Alternative fuels in fire debris analysis: biodiesel basics

Alternative fuels are becoming more prominent on the market today and, soon, fire debris analysts will start seeing them in liquid samples or in fire debris samples. Biodiesel fuel is one of the most common alternative fuels and is now readily available in many parts of the United States and around the world. This article introduces biodiesel to fire debris analysts. Biodiesel fuel is manufactured from vegetable oils and/or animal oils/fats. It is composed of fatty acid methyl esters (FAMEs) and is sold pure or as a blend with diesel fuel. When present in fire debris samples, it is recommended to extract the debris using passive headspace concentration on activated charcoal, possibly followed by a solvent extraction. The gas chromatographic analysis of the extract is first carried out with the same program as for regular ignitable liquid residues, and second with a program adapted to the analysis of FAMEs.     

Free Fatty Acids Composition in Adipocere of the Kwäday Dän Ts’ìnchí Ancient Remains Found in a Glacier*

Abstract: Adipocere is a postmortem decomposition product consisting of mostly a mixture of free fatty acids (FFAs) that are formed because of the hydrolysis of triglycerides in adipose tissues. This article describes a simple and robust method for the extraction, identification, and quantification of FFA commonly found in adipocere using gas chromatography–mass spectrometry (GC/MS). This method was applied to analyze tissues from Kwäday Dän Ts’ìnchí, ancient remains discovered in a retreating glacier in the Tatshenshini‐Alsek Park, British Columbia, Canada in August 1999. The lyophilized tissues were grinded and extracted with hexane. The trimethylsilyl fatty acid derivatives were analyzed by GC/MS, and the relative abundances of myristic acid, palmitic acid, oleic acid, and stearic acid were determined. Milligram per gram levels of saturated fatty acids were found in the tissues of the ancient remains, while the levels of unsaturated fatty acids, such as palmitoleic acid, were found to be negligible. The results provided further evidence of the existence of adipocere found during forensic examination of the Kwäday Dän Ts’ìnchí ancient remains.     

检察机关行使职务犯罪侦查权重述

当前,纪检监察机关和检察机关作为两大"主力"的多元反腐败机制存在较多不足,以致实效欠佳,且一些普遍性做法不完全符合现行法律、法规的规定。职务犯罪侦查权的本质是法律监督,可依循激活存量的思路,理顺二者的职能范围,使各安其所、各司其职,并完善相关配套机制和措施。目前,我们应以《人民检察院组织法》修改为契机,适度拓展检察职能。如此,既有利于实现反腐倡廉、建设法治化国家,也有利于实现依法执政、建设现代化中国。