Patella sex determination by 3D statistical shape models and nonlinear classifiers

Sex determination is one of the essential steps in personal identification of an individual from skeletal remains. Most elements of the skeleton have been subjected to discriminant function analysis for sex estimation, but little work has been done in terms of the patella. This paper proposes a new sex determination method from the patella using a novel automated feature extraction technique. A dataset of 228 patellae (95 females and 133 males) was amassed from the William M. Bass Donated Skeletal Collection from the University of Tennessee and was subjected to noninvasive high resolution computed tomography (CT). After the CT data were segmented, a set of features was automatically extracted, normalized, and ranked. The segmentation process with surface smoothing minimizes the noise from enthesophytes and ultimately allows our methods to distinguish variations in patellar morphology. These features include geometric features, moments, principal axes, and principal components. A feature vector of dimension 45 for each subject was then constructed. A set of statistical and supervised neural network classification methods were used to classify the sex of the patellar feature vectors. Nonlinear classifiers such as neural networks have been used in previous research to analyze several medical diagnosis problems, including quantitative tissue characterization and automated chromosome classification. In this paper, different classification methods were compared. Classification success ranged from 83.77% average classification rate using labels from a Fuzzy C-Means (FCM) clustering step, to 90.3% for linear discriminant classification (LDC). We obtained results of 96.02% and 93.51% training and testing classification rates, respectively, using feed-forward backpropagation neural networks (NN). These promising results using newly developed features and the application of nonlinear classifiers encourage the usage of these methods in forensic anthropology for identifying the sex of an individual from incomplete skeletons retaining at least one patella.     

Genetic and chemical components analysis of Papaver setigerum naturalized in Korea

Of the 110 species of genus Papaver, only Papaver somniferum and P. setigerum are controlled poppies in Korea. All poppy samples share similar morphology therefore it is important to check if they contain controlled substances such as morphine and codeine for forensic purpose. Since the alkaloid content of Papaver plants varies according to their growing stage, chemical components analysis alone is not enough to identify exact species. In 2010, hundreds of poppy plants suspected to be P. somniferum were found in Jeju Island, South Korea. They had a slightly different but overall similar appearance to P. somniferum. Using GC-MS analysis, codeine, rhoeadine, papaverine, protopine, noscapine, setigeridine and trace amounts of morphine were detected in these samples. Although their chemical components were different from what has been described in literatures for P. setigerum, they could be assumed to be P. setigerum based on their morphological features and GC-MS results. Also, chromosome numbers using their seeds showed 2n=44 and the numbers were in accordance with those of P. setigerum. Nucleotide substitution or insertion/deletion of ITS (internal transcribed spacer), 18S rRNA (ribosomal RNA), rbcL (large subunit of ribulose 1,5-bisphosphate carboxylase), trnL-trnF IGS (intergenic spacer), trnL intron and psbA-trnH were assessed as universal genetic markers for P. setigerum. Also, genetic analysis using six target genes involved in the biosynthesis of benzylisoquinoline alkaloids, including TYDC (tyrosine/dopa decarboxylase), SAT (salutaridinol-7-O-acetyltransferase), BBE (berberine bridge enzyme), COR (codeinone reductase), CYP80B1 ((S)-N-methylcoclaurine 3'-hydroxylase) and NCS (norcoclaurine synthase) were tested as Papaver-specific genetic markers by the existence of their PCR products. From the results, the sequences of the 6 universal genetic markers and 6 Papaver-specific genetic markers for P. setigerum were identified and then Genbank accession numbers of them were registered in NCBI. Also, the trnL intron and psbA-trnH nucleic acid sequences of the 7 Papaver species were identified and registered.     

Sex determination from the talus of Koreans by discriminant function analysis

The aims of this study were to investigate the sex discriminating potential of the talus in Koreans and compare this with other analyses in different populations. Statistical analyses were performed using data from nine measurements acquired from 140 tali (70 men, 70 women). The talus of Koreans is dimorphic between sexes in all measurements (p < 0.01). Discriminant function equations were generated by univariate, multivariate, and stepwise methods with a range of accuracy from 67.1 to 87.1%. Stepwise equations of other populations did not discriminate the sex of the Korean sample as accurately as each equation's own accuracies. The variables with high accuracy in this study are useful for sex determination of Koreans on the basis of confirmation of population specificity.     

《未成年人社会调查报告》的证据法分析

《未成年人社会调查报告》具有相关性、专业性和科学性、应用性,属于专家证据。社会调查员应当出庭质证,接受双方当事人的询问。法官应当结合其它证据对《报告》的可信性进行审查,并综合全案对其证明力大小作出判断。     

Variation in Adult and Juvenile Arrest Rates: The Influence of City Size and Metropolitan Environment

Since the mid-1990s, the index crime rate has steadily decreased while the rate for Part II offenses has increased. The current study examines these differences from 1990 to 2004 using arrest rate data from the 35 largest cities in the state of Texas. Cluster regression analyses is employed to examine the effect of city size and city location, whether the city is part of a larger metropolitan area or “stand-alone,” to explain variation in juvenile and adult arrest rates by category of offense (violent, property, Part II) while controlling for the influence of social disorganization variables. Findings indicate that differences exist in the arrest rates for almost all types of offenses in mid-size versus very large cities. Contrasting adult versus juvenile arrest rates, city size and city location offer limited explanation for variation over time. Implications of these findings are discussed in the context of suggested policy and research directions.     

常见嗜尸性甲虫及蝇类虫体不同部位mtDNA的提取效果

目的探讨改良后十六烷基三甲基溴化铵(cetyltriethylammnonium bromide,CTAB)法对常见嗜尸性昆虫虫体不同部位mtDNA的提取效果。方法随机采集放置在呼和浩特地区室外草地家兔尸体上丽蝇科的丝光绿蝇[Lucilia sericata(Meigen)]、埋葬甲科的Nicrophorus fossor(Erichson)各13例,采用改良CTAB法分别提取每只昆虫头部、胸肌、腿部、翅膀4个部位的mtDNA,核酸蛋白测定仪检测DNA纯度及质量浓度,琼脂糖凝胶电泳检测其PCR产物,测定PCR产物序列,上传GenBank。结果 13例丝光绿蝇[Lu-cilia sericata(Meigen)]的胸肌均提取到了DNA,10例头部样本、6例腿部样本、4例翅膀样本得到DNA;13例Nicrophorus fossor(Erichson)胸肌DNA均提取成功,5例头部样本、8例腿部样本及3例翅膀样本提取出DNA。结论改良CTAB法可用于对嗜尸性昆虫胸肌及其他部位进行DNA的提取。     

Discrimination of Falls and Blows in Blunt Head Trauma: A Multi‐Criteria Approach

Abstract: In the discrimination of falls versus blows, the hat brim line (HBL) rule is mentioned in several textbooks as the most useful single criterion. Recent studies, however, have found that the HBL rule is only moderately valid and that its use on its own is not recommended. The purpose of this 6‐year retrospective study was to find additional individually useful criteria in the distinction of falls from blows. Overall, the following criteria were found to point toward blows: more than three lacerations, laceration length of 7 cm or more, comminuted or depressed calvarial fractures, lacerations or fractures located above the HBL, left‐side lateralization of lacerations or fractures, more than four facial contusions or lacerations, presence of ear lacerations, presence of facial fractures, and presence of postcranial osseous and/or visceral trauma. Based on the most discriminating criteria, a decision tree was constructed to be potentially applicable to future cases.     

Speech Watermarking: An Approach for the Forensic Analysis of Digital Telephonic Recordings*

Abstract: In this article, the authors discuss the problem of forensic authentication of digital audio recordings. Although forensic audio has been addressed in several articles, the existing approaches are focused on analog magnetic recordings, which are less prevalent because of the large amount of digital recorders available on the market (optical, solid state, hard disks, etc.). An approach based on digital signal processing that consists of spread spectrum techniques for speech watermarking is presented. This approach presents the advantage that the authentication is based on the signal itself rather than the recording format. Thus, it is valid for usual recording devices in police‐controlled telephone intercepts. In addition, our proposal allows for the introduction of relevant information such as the recording date and time and all the relevant data (this is not always possible with classical systems). Our experimental results reveal that the speech watermarking procedure does not interfere in a significant way with the posterior forensic speaker identification.