Can computed tomography replace or supplement autopsy?

Postmortem computed tomography (PMCT) has been integrated into the practice of many forensic pathologists. To evaluate the utility of PMCT in supplementing and/or supplanting medicolegal autopsy, we conducted a prospective double-blind comparison of abnormal findings reported by the autopsy pathologist with those reported by a radiologist reviewing the PMCT. We reviewed 890 cases: 167 with blunt force injury (BFI), 63 with pediatric trauma (under 5 years), 203 firearm injuries, and 457 drug poisoning deaths. Autopsy and radiology reports were coded using the Abbreviated Injury Scale and abnormal findings and cause of death (COD) were compared for congruence in consensus conferences with novel pathologists and radiologists. Overall sensitivity for recognizing abnormal findings was 71% for PMCT and 74.6% for autopsy. Sensitivities for PMCT/autopsy were 74%/73.1% for BFI, 61.5%/71.4% for pediatric trauma, 84.9%/83.7% for firearm injuries, and 56.5%/66.4% for drug poisoning deaths. COD assigned by reviewing PMCT/autopsy was correct in 88%/95.8% of BFI cases, 99%/99.5% of firearm fatalities, 82.5%/98.5% of pediatric trauma deaths, and 84%/100% of drug poisoning deaths of individuals younger than 50. Both autopsy and PMCT were imperfect in recognizing injuries. However, both methods identified the most important findings and are sufficient to establish COD in cases of BFI, pediatric trauma, firearm injuries and drug poisoning in individuals younger than 50. Ideally, all forensic pathologists would have access to a CT scanner and a consulting radiologist. This would allow a flexible approach that meets the diagnostic needs of each case and best serves decedents' families and other stakeholders.     

Assessing the ‘Gold Standard’ of party policy placements: Is computerized replication possible?

The Comparative Manifestos Project (CMP) offers data on party policy positions based on a coding scheme of 56 categories. To what extent can we replicate the CMP coding results by using computerized topical coding of digitalised manifestos? Both human and computer coding have a number of strengths and weaknesses so that the combination of strengths could help to arrive at both valid and reliable party policy placements, in particular the measurement of policy movements over time. More than 1500 digitalised party manifestos in 20 democracies in the period 1960–2009 are re-coded with a computerized CMP-compatible coding scheme in order to assess the differences with human coding using exactly the same issue categories and the same left–right scale.The analysis shows that it is possible to use computer coding in order to locate the potential weakness of the human coding and the other way around. It also illustrates that the validity and reliability of policy placements is a function of the conceptualisation and operationalisation of issues, of the size of documents and of scale construction. Computerized cross-validation of the CMP-coding results offers a new and powerful tool to assess its reliability.     

脚步声识别技术研究进展

得益于高性能计算机和深度学习算法的不断进步,生物特征识别技术得到快速发展。脚步声识别技术利用人行走时发出的声音或震动信号实现行走人的身份识别,具有隐蔽性、非接触式、不易被伪造和无需被识别人配合等优点,是一种非常有潜力的生物特征识别技术。本文概述了脚步声识别系统的组成部分、基本概念以及脚步声识别系统的性能评价指标,总结了脚步声识别技术中的信号采集方法及其使用的仪器设备、降噪和端点检测信号预处理关键技术、时频域和声学特征参数提取、各种模式识别方法在脚步声识别技术中的应用等方面的研究成果。最后,系统地分析了脚步声识别技术研究中尚未解决的问题,探讨了该研究领域需要进一步探索的热点问题和未来的发展趋势。     

Complete mitochondrial genome sequences for 265 African American and U.S. “Hispanic” individuals

Entire mitochondrial genome (mtGenome) sequences of 265 unrelated African American and U.S. “Hispanic” individuals were generated.     

Precedents,Progress, and Prospects in Political Event Data

The past decade has seen a renaissance in the development of political event data sets. This has been due to at least three sets of factors. First, there have been technological changes that have reduced the cost of producing event data, including the availability of information on the Web, the development of specialized systems for automated coding, and the development of machine-assisted systems that reduce the cost of human coding. Second, event data have become much more elaborate than the original state-centric data sets such as WEIS and COPDAB, with a far greater emphasis on substate and nonstate actors, and in some data sets, the incorporation of geospatial information. Finally, there have been major institutional investments, such as support for a number of Uppsala and PRIO data sets, the DARPA ICEWS Asian and global data sets, and various political violence data sets from the US government. This article will first review the major new contributions, with a focus on those represented in this special issue, discuss some of the open problems in the existing data and finally discuss prospects for future development, including the enhanced use of open-source natural language processing tools, standardizing the coding taxonomies, and prospects for near-real-time coding systems.     

中国朝鲜族线粒体DNA编码区序列多态性

目的调查中国朝鲜族群体线粒体DNA（mtDNA）编码区内5个部位 3954～4506nt、5218～5974nt、7942～871Int、10296～10653nt 及14496～14867nt的序列多态性。方法采用PCR产物直接测序方法,对212名中国朝鲜族（吉林省延边地区）无关个体进行序列多态性变化和单倍型分布调查。结果在212名无关个体中,共分出148种单倍型。遗传变异度为0．9931,耦合概率为0．0116。测序结果与Anderson标准序列比较,共检测出109个变异位点,其中79个已收录于MITOMAP。结论mtDNA编码区多态性联合应用可以提高mtDNA的个体识别能力。町为相关遗传学研究提供基础数据资料。     

Forensic Informativity of ~3000 bp of Coding Sequence of Domestic Dog mtDNA

The discriminatory power of the noncoding control region (CR) of domestic dog mitochondrial DNA alone is relatively low. The extent to which the discriminatory power could be increased by analyzing additional highly variable coding regions of the mitochondrial genome (mtGenome) was therefore investigated. Genetic variability across the mtGenome was evaluated by phylogenetic analysis, and the three most variable ~1 kb coding regions identified. We then sampled 100 Swedish dogs to represent breeds in accordance with their frequency in the Swedish population. A previously published dataset of 59 dog mtGenomes collected in the United States was also analyzed. Inclusion of the three coding regions increased the exclusion capacity considerably for the Swedish sample, from 0.920 for the CR alone to 0.964 for all four regions. The number of mtDNA types among all 159 dogs increased from 41 to 72, the four most frequent CR haplotypes being resolved into 22 different haplotypes.     

Analytical Thresholds and Sensitivity: Establishing RFU Thresholds for Forensic DNA Analysis,

Determining appropriate analytical thresholds (ATs) for forensic DNA analysis is critical to maximize allele detection. In this study, six methods to determine ATs for forensic DNA purposes were examined and compared. Four of the methods rely on analysis of the baseline noise of a number of negatives, while two utilize the relationship between relative fluorescence unit signal and DNA input in the polymerase chain reaction (PCR) derived from a dilution series ranging from 1 to 0.06 ng. Results showed that when a substantial mass of DNA (i.e., >1 ng) was amplified, the baseline noise increased, suggesting the application of an AT derived from negatives should only be applied to samples with low levels of DNA. Further, the number and intensity of these noise peaks increased with increasing injection times, indicating that to maximize the ability to detect alleles, ATs should be validated for each post‐PCR procedure employed.     

信息理论与编码课程教学形式的整合应用

该文首先叙述了板书教学、多媒体教学、网络教学这三种教学形式的优缺点,提出教学形式的选择或整合应当结合具体教学内容。其次,提出了在“信息理论与编码”课程中将三种教学形式整合应用的方法。     

Do Juries Meet Our Expectations?

Surveys of public opinion indicate that people have high expectations for juries. When it comes to serious crimes, most people want errors of convicting the innocent (false positives) or acquitting the guilty (false negatives) to fall well below 10%. Using expected utility theory, Bayes' Theorem, signal detection theory, and empirical evidence from detection studies of medical decision making, eyewitness testimony, and weather forecasting, we argue that the frequency of mistakes probably far exceeds these tolerable levels. We are not arguing against the use of juries. Rather, we point out that a closer look at jury decisions reveals a serious gap between what we expect from juries and what probably occurs. When deciding issues of guilt and/or punishing convicted criminals, we as a society should recognize and acknowledge the abundance of error.