ISFG: Recommendations on biostatistics in paternity testing

The Paternity Testing Commission (PTC) of the International Society for Forensic Genetics has taken up the task of establishing the biostatistical recommendations in accordance with the ISO 17025 standards and a previous set of ISFG recommendations specific to the genetic investigations in paternity cases. In the initial set, the PTC recommended that biostatistical evaluations of paternity are based on a likelihood ratio principle – yielding the paternity index, PI. Here, we have made five supplementary biostatistical recommendations. The first recommendation clarifies and defines basic concepts of genetic hypotheses and calculation concerns needed to produce valid PIs. The second and third recommendations address issues associated with population genetics (allele probabilities, Y-chromosome markers, mtDNA, and population substructuring) and special circumstances (deficiency/reconstruction and immigration cases), respectively. The fourth recommendation considers strategies regarding genetic evidence against paternity. The fifth recommendation covers necessary documentation, reporting details and assumptions underlying calculations. The PTC strongly suggests that these recommendations should be adopted by all laboratories involved in paternity testing as the basis for their biostatistical analysis.     

海洛因来源鉴定的新方法

毒品来源的鉴定是指对毒品样品中包含的来源信息进行提取拜分析,这有助于打击毒品犯罪.海洛因是危害我国的主要毒品,它的来源鉴定更引起人们的关注.本文介绍了国际上研究海洛因来源的三种方法,即研究海洛因样品中的各种有机杂质及其相对比例;研究海洛因样品中的痕量无机元素;研究海洛因及吗啡的稳定同位素相对比值.第三种方法能够反映样品的地域性特点,因而在来源鉴定方面有突出的优势.气相色谱-燃烧-同位素比值质谱法是同位素比值测定方法中用于海洛因来源鉴定的最佳手段.这一技术还可用于其他微量物证(如炸药、药品、油品等)的来源鉴别,因而在法庭科学领域内显示了广阔的应用前景.     

Short term impact of Tribulus terrestris intake on doping control analysis of endogenous steroids

Tribulus terrestris is a nutritional supplement highly debated regarding its physiological and actual effects on the organism. The main claimed effect is an increase of testosterone anabolic and androgenic action through the activation of endogenous testosterone production. Even if this biological pathway is not entirely proven, T. terrestris is regularly used by athletes. Recently, the analysis of two female urine samples by GC/C/IRMS (gas chromatography/combustion/isotope-ratio-mass-spectrometry) conclusively revealed the administration of exogenous testosterone or its precursors, even if the testosterone glucuronide/epitestosterone glucuronide (T/E) ratio and steroid marker concentrations were below the cut-off values defined by World Anti-Doping Agency (WADA). To argue against this adverse analytical finding, the athletes recognized having used T. terrestris in their diet. In order to test this hypothesis, two female volunteers ingested 500 mg of T. terrestris, three times a day and for two consecutive days. All spot urines were collected during 48 h after the first intake. The (13)C/(12)C ratio of ketosteroids was determined by GC/C/IRMS, the T/E ratio and DHEA concentrations were measured by GC/MS and LH concentrations by radioimmunoassay. None of these parameters revealed a significant variation or increased above the WADA cut-off limits. Hence, the short-term treatment with T. terrestris showed no impact on the endogenous testosterone metabolism of the two subjects.     

夫妻一方对他方自杀而“见死不救”之刑事责任新探——从“宋福祥故意杀人案”之判决理由谈起

"罪刑法定原则"与"罪刑相适应原则"已经成为我国刑法的基本原则。"宋福祥故意杀人案"之判决理由欠缺合理性与合法性,夫妻一方对他方自杀而"见死不救"的不应当承担刑事责任。在刑事审判中,法官应"以事实为根据,以法律为准绳",以作出正当的个案裁判为己任,在审判中真正做到符合"罪刑法定原则"与"罪刑相适应原则",才能切实保障公民的合法权益,维护社会的和谐稳定,也才能真正实现依法治国。     

The Measurement of Stable Carbon Isotope Ratios of Eight Methamidophos Samples

Between December 2007 and January 2008, people suffered from food poisoning in the Japanese prefectures of Chiba and Hyogo after eating frozen dumplings (gyoza) produced in China, which had very high concentrations (1490–19,290 ppm) of methamidophos (O,S‐dimethyl phosphoramidothioate). Thus, we measured the stable carbon isotope ratio of methamidophos using GC/C/IRMS to identify the source. We analyzed seven methamidophos reagents and one Chinese agricultural methamidophos chemical (MTD600) that contained many impurities. The δ¹³C values of the seven methamidophos reagents and MTD600 ranged from ?49.23‰ to ?31.90‰, with an average SD of 0.20‰, very high precision. This difference (17.33‰) was very large compared with that in previous reports and may be attributable to the material itself and the chemical processing of methamidophos. Criminals can easily obtain pesticides such as methamidophos; therefore, it is very important to identify the pesticide source and distribution route using stable isotopic science in the future.     

Establishing the Limits of TrueAllele® Casework: A Validation Study

The limits of the expert system, TrueAllele^® Casework (TA), were explored using challenging mock casework profiles that included 17 single‐source and 18 two‐, 15 three‐ and 7 four‐person DNA mixtures. The sensitivity (ability to detect a minor contributor) of the TA analysis process was examined by challenging the system with mixture DNA samples that exhibited allelic and locus dropout and other stochastic effects. The specificity (ability to exclude nondonors) was rigorously tested by interrogating TA derived genotypes with 100 nondonor profiles. The accuracy with which TA estimated mixture weights of contributors to the two‐person mixtures was examined. Finally, first‐degree relatives of donors were used to assess the ability of the system to exclude close relatives. TA demonstrated great accuracy, sensitivity, and specificity. TA correctly assigned mixture weights and excluded nearly all first‐degree relatives. This study demonstrates the analysis power of the TrueAllele^® Casework system.     

我国汽车保险业务发展问题研究

近年来，我国汽车保险业务发展迅速，保费收入不断增长，车险业务保费收入占产险公司总保费收入的比重也连创新高。但在车险业务快速发展的同时，经营效益欠佳日益引起人们的关注，行业亏损已成为大家公认的看法，在此背景下，本文利用大量翔实的数据深入分析了我国车险业务的保费收入情况和赔付支出情况，并相应分析了我国车险业务经营亏损的原因及对策。     

实验性急性心肌梗死心肌K~+/Na~+、Mg~(2+)/Ca/~(2+)Zn~(2+)/Cu~(2+)比值变化的研究

用结扎家免左冠状动脉建立急性心肌梗死区的模型,探讨梗死区心肌中K~+/Na~+、Mg~(2+)/Ca/~(2+)、Zn~(2+)/Cu~(2+)比值的变化与急性心肌梗死发生时间的规律。结果提示:(1)K~+/Na~+、Mg~(2+)/Ca/~(2+)比值随心肌缺血时间延长呈进行性下降。K~+/Na~+比值在60min、120min实验组与对照组比较有显著性差异(P<0.01);(2)Zn~(2+)/Cu~(2+)比值各实验组与对照组比较无显著性差异(P>0.05),但实验组随缺血时间延长,Zn~(2+)/Cu~(2+)比值呈下降趋势,120min组比15min、30min、60min组降低约1/2(PC<0.01)。测定心肌梗死区K~+/Na~+、Mg~(2+)/Ca/~(2+)比值可以作为显示和判定急性心肌梗死的重要指标。     

根据足迹掌宽值推断体重公式的修正计算

目的为提高实战中对留痕人体重推断的准确率;方法根据足迹长宽的比值更能准确地反映人的胖瘦这一规律,提出修正计算公式m=2.5M/R进行初步实验检验;结果该方法是对原根据足迹掌宽值推断留痕人体重公式的补充,对偏离标准体态的人,用该公式修正使足迹掌宽值与体重的关系有了较为准确的反映。