SMART:自主研发的混合STR图谱分析系统

目的混合STR图谱的分析是法医遗传学领域的一个难题。目前国内大多数法医DNA实验室依靠人工方法分析混合STR图谱,费时费力,且拆分效果也多有主观性,难以满足日益增长的混合STR图谱分析的需求。本文介绍一套自主研发的混合STR图谱分析系统——SMART(STR Mixture Analysis and Resolution Tools),其能够实现对混合STR图谱的自动化分析,包括拆分混合STR图谱和计算似然比。方法SMART使用的STR峰高的概率模型,考虑了影子峰、降解、基因座特异性扩增效率、峰高变异、插入峰、峰丢失等因素。模型通过比较各个基因型集合拟合当前混合STR图谱的似然值大小来推断最有可能的基因型集合,采用了马尔可夫链蒙特卡洛(MCMC)算法进行求解。结果SMART可应用于不同试剂盒和遗传分析仪产生的数据。经使用ABI-3500XL遗传分析仪和Global Filer试剂盒测试,SMART能够实现对2~5人的混合STR图谱的分析,输出包括混合比例、混合图谱质量、各个贡献者单人的STR基因分型、似然比等多项结果。结论SMART作为一款自主研发的混合STR图谱分析系统,其基本涵盖了国外同类分析系统所具有的功能,技术性能指标达到国际先进水平,能够满足一线法医工作者对于混合STR图谱分析的多样化需求,提高混合STR图谱结果的利用率。     

Observer determination of the make,model, and year of questioned vehicles

Often, criminal acts involving a vehicle are caught on digital video surveillance systems. While potentially useful for an investigation, the recording conditions are typically less than optimal for the extraction of key information for the identification of the perpetrator, such as a license plate. Providing the make, model and year of a questioned vehicle is a common request for examiners, to narrow the field of potential suspect vehicles. This study seeks to compare the performance of a nonpeer-reviewed make, model, and year determination between two separate groups, specifically, trained forensic image examiners and nontrained individuals. Results show that even with varied image capture conditions and quality, the trained forensic image examiners more correctly and completely identified the test group of questioned vehicles make, model, and year.     

以共同育儿为业:跨越儿童抚育的家庭边界——以一个城市社区的“抱团养娃”实践为例

本文聚焦于城市化背景下的"抱团养娃"实践,深入探讨在抚育职责被"家庭化"的当下,抚育实践如何在一定程度上重新跨越"家庭"的边界。以社区共育为基点,妈妈们的努力既从私人层面上为在陌生城市中资源不足的小家庭找到更多社会支持,又在公共层面上带动孩子们以温度和情感重塑社区认同、黏合社会转型带来的制度缝隙,体现出独特的现实意义与支持力量。"以共同育儿为业"背后,是女性试图在既有的结构约束下找到被私人化的抚育照料重担与公共生活之间的连接点,在本研究中体现为共育支持网络的形成、共育友好空间的营造、亲子活动内容的生产和共育文化的建构四个方面。这为思考如何将"社会"重新带回抚育实践中提供了想象,也拓宽了对女性主体性的理解。     

江西省餐具、饮具集中消毒服务单位现状调查及分析

目的:了解江西省餐具、饮具集中消毒服务单位现状。方法:对江西省内所有持工商营业执照的餐具、饮具集中消毒服务单位开展问卷调查,并作统计分析。结果:江西省共有166家持证的餐具、饮具集中消毒服务单位,78.92%为私有制,90.96%的单位日产量在1万套以下。厂区选址和内环境合格率分别为14.46%、63.25%,生产车间装修合格率为57.83%,60.24%的单位采用全自动化生产设备。成品仓储、运输过程卫生合格率分别为38.55%、39.76%,生产记录、出厂检验、包装标识合格率依次为37.35%、54.22%、77.71%。结论:江西省餐具、饮具集中消毒服务单位以中小规模的私营单位为主,现场卫生问题突出,建议通过完善法律、前置卫生审核、强化主体责任意识、卫生质量控制等措施,改善行业现状。     

Development of an instrument for assessing the quality of forensic evidence and expert testimony from three feature-comparison methods: DNA,voice, and fingerprint analysis

In a context of rising violence and long-lasting impunity, in 2008, Mexico's criminal justice system underwent a radical change from an inquisitorial model to an adversarial one, to make it more effective, transparent, and expeditious. The new system tasked judges with publicly determining the admissibility of forensic evidence, as well as assessing its technical quality and probative value—tasks for which they currently receive little to no training. With the aim of contributing to the consolidation of the adversarial model, a comparative framework—in the form of a checklist—of the analysis of fingerprints, DNA samples, and voice recordings was created. To do so, a review of the academic literature, published reports, and guidelines was performed. The collected data were synthesized and submitted to a panel of Mexican judges, who provided feedback on its adequacy. The framework focuses on the steps on which quality assurance of forensic evidence depends, organized in five discrete stages that span from the collection of samples at the scene of a crime to the presentation of evidence at trial, specifying the main technical criteria experts should state to allow a decision maker to examine its accuracy and reliability. Differences and commonalities among the three methods were identified, particularly in terms of how qualitative and quantitative analyses are performed in each. Besides its potential usefulness as an aid for judicial decision-making, the checklist could be a valuable resource for training programs aimed at judges, as well as quality assurance programs.     

Empirical validation of a family-member prioritization approach to maximize statistical power in missing person cases

In order to prioritize the exhumation of the most informative reference relatives to increase the statistical power of a reference group, a conditional simulation approach for missing person identification that combines both exclusion and inclusion power in reference families has been previously developed. The aim of this study is to empirically validate this approach by comparing its predicted theoretical prioritization model with the observed changes in statistical power in real cases of our laboratory, in which new relatives had already been added. We conclude that this approach is a reliable tool to choose the most appropriate reference relatives to complete a family group and improve the identification power of a Missing Person (MP).     

193例持续性姿势-知觉性头晕患者中医证候研究

目的 通过因子分析探索持续性姿势-知觉性头晕（persistent postural-perceptual dizziness，PPPD）的中医证候特点。方法 采集193例PPPD病例症状、舌象、脉象，将每一症状、舌象、脉象作为一个统计变量，“有”则赋值为“1”、“无”则赋值为“0”，计算四诊信息的频数和频率，运用因子分析对高频症状、舌象及脉象进行非线性降维并提取公因子，得出病性、病位证素及中医证型并加以总结分析。结果 频率排名前3位症状的依次为头晕（90.67%）、心烦（54.40%）、倦怠乏力（51.30%），舌象中舌质频率最高者为舌质暗红（22.28%），舌苔频率最高者为白苔（31.09%），脉象频率最高者为滑脉（41.97%）。利用因子分析共提取13个公因子，累计贡献率为64.798%。整合相同的证素，共得到5个病性证素，依次是气滞（71.50%）、阴虚（24.35%）、血虚（22.28%）、气虚（17.10%）、痰湿（15.03%）；5个病位证素，依次是肝（93.26%）、肾（24.35%）、脾（16.58%）、心（0.52%）；6个中医证型，依次是肝郁气滞证（56.48%）、肝肾阴虚证（21.76%）、肝郁脾虚证（15.03%）、肾阴虚证（2.59%）、脾肾阴虚证（1.55%）、气血两虚证（0.52%）。结论 PPPD的病性证素以气滞为主，病位证素以肝为主，中医证型以肝郁气滞证为主。     

Discrimination and ethnic conflict: a dyadic analysis of politically-excluded groups in sub-Saharan Africa

ABSTRACT

The literature on political exclusion and conflict tends to treat grievance-based mechanisms with broad-brush strokes and does not differentiate between types of political exclusion. This study disaggregates politically-excluded groups into two subgroups: groups that experience political discrimination from the state, and groups without political power that are not explicitly discriminated against. We posit that discriminated groups are more likely to experience grievances and therefore are more prone to conflict than excluded groups that are not actively discriminated against. We further posit that the effect of discrimination on conflict is moderated by interactions with economic inequalities and the share of elites. Using dyadic data for 155 ethnic groups in 28 Sub-Saharan African countries, we find that among politically-excluded groups it is indeed discriminated groups that are responsible for most of the association between political exclusion and conflict. Groups that face active, intentional, and targeted discrimination by the state are significantly more likely to be involved in conflict than excluded groups who do not face this explicit form of discrimination. Additionally, we find that discriminated groups who also experience economic inequalities are less likely to engage in conflict, whilst an increased presence of elites within discriminated groups can precipitate the chances of conflict.     

Strategic rebels: a spatial econometric approach to rebel fighting durations in civil wars

ABSTRACT

Recent research on multi-actor civil wars highlights that rebel organizations condition their conflict behavior on that of other rebel organizations, with competition and free-riding constituting the core theoretical mechanisms. We provide a new actor-centric approach to explicitly model strategic interdependence in multi-actor civil wars. We argue that rebel organizations have incentives to remain mobilized until the end of a conflict to maintain their power to negotiate, power to spoil, power to enforce, and power to protect. This induces strategic complements that dominate duration dynamics in multi-actor conflicts. Based on a network game-theoretic model, we derive a spatial econometric framework that allows for a direct test of strategic interdependence. We find that the estimated duration interdependence is positive but partially offset in secessionist conflicts where the public goods nature of the incompatibility also induces strategic substitution effects.     

“UNUSUAL” TISSUES AND SAMPLE COLLECTION STRATEGIES ON EXHUMED BODIES

The choice of soft or hard tissues to be sampled in case of exhumation of corpses for identification purposes or family relationship testing is based on the degradation conditions of the corpse: the more the corpse is degraded, the less DNA is expected to be retrieved from soft tissue. Therefore, the choice of the "best" tissue samples usually falls on teeth and bones in these “difficult” cases, even though the DNA extraction procedure requires time and effort and it can often result in unexpected, negative results.We here present the results of a daily practice survey that shows that it is possible to obtain good results even on DNA extracted from tissues that appear to be less “appealing” to the examiner by performing “simple” corneal/scleral swabs along with cartilage.While DNA extracted from cartilage has been already described, to our knowledge there is no evidence of publications in the scientific literature dealing with cornea/sclera as a source of DNA in the forensic laboratory.The obtained results demonstrate that it may be advisable to consider other tissues which bear the potential of returning good profile results despite not appearing particularly useful and better control of contamination.