Sexual dimorphism in the crania and mandibles of South African whites

Numerous studies have clearly demonstrated that skeletal characteristics vary by population. To date, there are no metric cranial criteria for South African whites. Therefore, the purpose of this study is to establish population specific standards for sex determination from the skull. A total of 12 standard cranial and five mandibular measurements were taken from 44 male and 47 female skeletons of known sex and race from the Pretoria and Dart collections. These were subjected to SPSS discriminant function analysis. Bizygomatic breadth was the most dimorphic dimension. Five functions were developed from the complete cranium, vault, face, mandible and bizygomatic breadth. Dimensions from the complete cranium provided the best accuracy. In the mandible, bigonial breadth was the most dimorphic of the measurements taken. Average accuracies ranged from 80% (bizygomatic breadth alone) to 86% (cranium). These accuracies are similar to those obtained by researchers on other groups (e.g., 84% in Japanese crania and about 86% in American whites and blacks). Diagnostic accuracy, however, is lower than that obtained from the South African femur and tibia.     

Sexual dimorphism in the subadult mandible: quantification using geometric morphometrics

There have been numerous attempts, with varying degrees of success, to differentiate males from females on the basis of the immature skeleton. We investigate here whether the mandible can discriminate immature individuals by sex; the techniques we apply are from the field of geometric morphometrics. The application of these methods in forensic anthropology is still relatively new; thus, an important aspect of this research is that it demonstrates potential applications in this discipline. The sample comprises 96 known age and sex subadult individuals; the three-dimensional coordinates of 38 landmarks are analyzed using the shape analysis software morphologika. Multivariate regressions indicated no significant sexual dimorphism in the subadult sample; this result is supported by poor cross-validated classification accuracy (59%). Our results suggest that the subadult mandible is not dimorphic (to the extent that dimorphism is not evident within the sample we studied); thus, sex determination using previously described criteria is likely to yield poor results.     

Identification of group affinity from cross-sectional contours of the human midfacial skeleton using digital morphometrics and 3D laser scanning technology

Identifying group affinity from human crania is a long-standing problem in forensic and physical anthropology. Many craniofacial differences used in forensic skeletal identification are difficult to quantify, although certain measurements of the midfacial skeleton have shown high predictive value for group classifications. This study presents a new method for analyzing midfacial shape variation between different geographic groups. Three-dimensional laser scan models of 90 crania from three populations were used to obtain cross-sectional midfacial contours defined by three standard craniometric landmarks. Elliptic Fourier transforms of the contours were used to extract Fourier coefficients for statistical analysis. After cross-validation, discriminant functions based on the Fourier coefficients provided an average of 86% correct classifications for crania from the three groups. The high rate of accuracy of this method indicates its usefulness for identifying group affinities among human skeletal remains and demonstrates the advantages of digital 3D model-based analysis in forensic research.     

Sexual Dimorphism of the Fetal Ilium: A 3D Geometric Morphometric Approach with Multislice Computed Tomography

Adult sexual dimorphism is well established. However, data regarding fetuses are sparse with contradictory results. Our study aimed to look for fetal sexual dimorphism. Multislice computed tomography (MSCT) examinations and three‐dimensional (3D) reconstructions were recorded on 93 fetal iliac bones aged between 21 and 40 weeks of amenorrhea (WA). The collection was divided into two age groups, with a cutoff at 30 WA. The 3D geometric morphometric analysis was based on outline analysis. We used elliptic Fourier analysis (EFA) because of the difficulty of landmark positioning. Step‐by‐step reconstructions allowed a better comprehension of the fine shape details. Principal component analysis (PCA) and linear discriminant analysis (LDA) were performed on the two age groups. Results did not show any difference between male and female shapes, in both age groups. We demonstrate the feasibility of outline analysis for immature shapes, but sexual dimorphism has not been established in our collection.     

Impacts of increasing volume of digital forensic data: A survey and future research challenges

A major challenge to digital forensic analysis is the ongoing growth in the volume of data seized and presented for analysis. This is a result of the continuing development of storage technology, including increased storage capacity in consumer devices and cloud storage services, and an increase in the number of devices seized per case. Consequently, this has led to increasing backlogs of evidence awaiting analysis, often many months to years, affecting even the largest digital forensic laboratories. Over the preceding years, there has been a variety of research undertaken in relation to the volume challenge. Solutions posed range from data mining, data reduction, increased processing power, distributed processing, artificial intelligence, and other innovative methods. This paper surveys the published research and the proposed solutions. It is concluded that there remains a need for further research with a focus on real world applicability of a method or methods to address the digital forensic data volume challenge.     

Virtual determination of sex: metric and nonmetric traits of the adult pelvis from 3D computed tomography models

Examination of the adult os coxae and sacrum is one of the most common methods of sex estimation from bone. Medical imaging, such as computed tomography (CT), provides the opportunity for three-dimensional (3D) imaging of the skeleton from clinical scans of known individuals in situ. In this study, a randomly selected subset of abdominopelvic CT-derived models were used to evaluate simple, repeatable metric methods of sex estimation based on a combination of obstetric measurements and the traditionally nonmetric Phenice-derived traits. A four-variable discriminant function for sex estimation was developed based on statistical analyses. Overall, the cross-validated accuracy of this method was 100%, with inter-observer error showing an average of only 2.2%. Comparative analysis was run on the data set using FORDISC 3.0. This study shows that current sex determination standards from the pelvis should be updated to include more in vivo data to increase the accuracy of identification.     

A new method of age estimation based on the changes in human non-collagenous proteins from dentin

The new method exploits the characteristic of staphylococcal protease V8, which specifically splits peptide bonds where l-glutamic or l-aspartic acid participate. Those peptide bonds where d-aspartic acid is present remain unsplit because of the stereospecifity of enzymes. In accordance with expectations, fewer peptide bonds are split by this protease at more advanced ages and larger peptide fragments are thus formed due to the higher content of d-amino acid residues in the proteins of older people. The samples of acid-extracted non-collagenous proteins from dentin were separated using high performance liquid chromatography after enzymatic hydrolysis. A peak with a retention time of 45.3 min was chosen and his enlarging area showed a linear correlation with increasing age. Although the linear correlation with age was proved, the scattering of values decreases the usefulness of the proposed method for age estimation.     

A new approach to amino acid racemization in enamel: testing of a less destructive sampling methodology

Aspartic acid racemization has been found to be an accurate measure of age at death for recent forensic material. This paper examines the practicality of using acid etching of the tooth surface to extract amino acids from the enamel for racemization analysis. By serial etching of the tooth and contamination of the teeth with bovine serum albumin prior to etching, the ability of etching to remove contamination was assessed. The destructiveness of the method was visualized and quantified using micro-computed tomography (micro-CT). By bleaching the teeth and by deeper etching it was possible to obtain more consistent values. While etching had little effect on the enamel at the macroscale, it did have an impact at the microscale. The quantities of enamel removed varied depending upon the tooth morphology, but were not large. Acid etching of enamel thus appears to be a promising new method for extracting proteins for amino acid racemization age estimation noninvasively.     

Morphometric Comparison of Clavicle Outlines from 3D Bone Scans and 2D Chest Radiographs: A Shortlisting Tool to Assist Radiographic Identification of Human Skeletons

This paper describes a computerized clavicle identification system primarily designed to resolve the identities of unaccounted‐for U.S. soldiers who fought in the Korean War. Elliptical Fourier analysis is used to quantify the clavicle outline shape from skeletons and postero‐anterior antemortem chest radiographs to rank individuals in terms of metric distance. Similar to leading fingerprint identification systems, shortlists of the top matching candidates are extracted for subsequent human visual assessment. Two independent tests of the computerized system using 17 field‐recovered skeletons and 409 chest radiographs demonstrate that true‐positive matches are captured within the top 5% of the sample 75% of the time. These results are outstanding given the eroded state of some field‐recovered skeletons and the faintness of the 1950's photofluorographs. These methods enhance the capability to resolve several hundred cold cases for which little circumstantial information exists and current DNA and dental record technologies cannot be applied.     

Sexual fantasy in paedophile offenders: Can any model explain satisfactorily new findings from a study of Internet and contact sexual offenders?

Purpose. There is widespread acceptance that sexual fantasy plays a role in sexual offences but little clarity as the nature of this relationship. This paper seeks to understand better the role of fantasy in offending behaviour through the study of sexual fantasy in Internet child pornography offenders when compared with contact offenders. Differences in the patterns of sexual fantasy associated with the different offender types are explored in order to understand how fantasy content is associated with contact offences with children and desisting from such direct acting out. Methods. Participants were all convicted of child sexual offences and recruited with the help of the probation and prison services. Out of these, 16 were Internet‐only offenders, 25 were contact offenders with no history of Internet offending and 10 were offenders with a mixed contact and Internet offending history. A variety of self‐completion questionnaires including fantasy were completed on an individual basis together with a detailed interview. Results. The most common sexual fantasies were typical adult‐male heterosexual fantasies though a variety of child‐oriented and other fantasies were also common. Contact offenders reported fewer girl‐oriented sexual fantasies although the groups did not differ in terms of terms of boy‐oriented fantasies. There was evidence that confrontational fantasies were commoner among contact offenders than Internet offenders. There are relationships between early sexual experiences and fantasy but peer sexual contacts seemed to be important rather than sexual abuse. Conclusion. Generally, the contact offenders seem to have less sexual fantasy pertinent to their offending than did Internet offenders. Fantasy deficit may be involved in contact offending against children.     

Drilling down into ethics: A thematic review of ethical considerations for the creation and use of 3D printed human remains in crime reconstruction

The existing literature contains some exploration of the ethics concerning human remains in forensic and virtual anthropology. However, previous work has stopped short of interrogating the underlying ethical concepts. The question of how people understand and apply these concepts in practice, and what it means to act ethically, remain underexplored. This thematic review explores the ethical considerations that contribute to the creation and use of 3D printed human remains for forensic purposes. The three main branches of ethical theory are outlined to explore how they may apply to forensic practice. Key themes relating to 3D printing human remains in forensic contexts were explored to better understand the ethics landscape, ethical challenges, and the current guidelines in place. Through this thematic review, nine ethics principles were identified as key principles for guiding best practice: anonymity, autonomy, beneficence, consent, context, justice, non-maleficence, proportionality, and transparency. It is suggested that these principles could be incorporated into adaptable guidelines going forward to support ethical practice. The findings also suggest that holistic ethics cognition training may have value in supporting forensic scientists in ethical decision-making, together with procedural and structural design that may promote best practice and reduce cognitive load.     

A case of tri-allelic pattern at locus D3S1358 on chromosome 3p21 inherited from paternal grandmother

We are reporting a case of tri-allelic inheritance at locus D3S1358 commonly used for genetic identification in forensic DNA testing. This case was encountered during routine paternity testing using commercial DNA profiling kits. The tri-allelic inheritance identified was probably a result of duplication at this locus, supported by the equal peak intensities and inheritance pattern from grandparent to child.     

A new approach to measuring time-lags in technology licensing: study of U.S. academic research institutions

This paper contributes to measurement of licensing performance of U.S. research institutions by suggesting an approach for identifying time-lags in the licensing process. Licensing is a multi-state process starting with a disclosure, and resulting in intermediate outcomes such as patents, licensing agreements, and licensing income. The time duration among these variables is critical in understanding which investment is responsible for which outcome. This study develops a statistic procedure estimating time-lag coefficients among licensing variables using an unstructured regression model (OLS). The procedure is applied to 46 U.S. academic research institutions using the licensing survey data from 1991 to 2007 by Association of University Technology Manager. The results present individual time-lag relationships between each pair of licensing variables.     

The size of the underground economy in Germany: a correction of the record and new evidence from the modified-cash-deposit-ratio approach

Based on the Ahumada et al. (Rev Income Wealth 53(2):363–371, 2007) critique we revise existing estimates of the size of the German underground economy. Among other things, it turns out that most of these estimates are untenable and that the tax pressure induced size of the German underground economy may be much lower than previously thought. To this extent, German policy and law makers have been misguided during the last three decades. Therefore, we introduce the Modified-Cash-Deposit-Ratio approach, which is not subject to the recent critique and apply it to Germany for the period 1960–2008.     

A method of human diaphorase locus 3 phenotyping in human semen by isoelectric focusing

A rapid method for the separation of diaphorase (DIA 3) isozymes in the pH range 6-8 is presented. Isoelectric focusing (IEF) of DIA 3 on 0.2 mm thick polyacrylamide gels took 60 min at 5 degrees C. Separated bands are sharp and common phenotypes are readily distinguishable. The method combines high resolution, speed, reproducibility and reagent economy with simplicity.     

A View to the Future: A Novel Approach for 3D–3D Superimposition and Quantification of Differences for Identification from Next‐Generation Video Surveillance Systems

Techniques of 2D–3D superimposition are widely used in cases of personal identification from video surveillance systems. However, the progressive improvement of 3D image acquisition technology will enable operators to perform also 3D–3D facial superimposition. This study aims at analyzing the possible applications of 3D–3D superimposition to personal identification, although from a theoretical point of view. Twenty subjects underwent a facial 3D scan by stereophotogrammetry twice at different time periods. Scans were superimposed two by two according to nine landmarks, and root‐mean‐square (RMS) value of point‐to‐point distances was calculated. When the two superimposed models belonged to the same individual, RMS value was 2.10 mm, while it was 4.47 mm in mismatches with a statistically significant difference (p < 0.0001). This experiment shows the potential of 3D–3D superimposition: Further studies are needed to ascertain technical limits which may occur in practice and to improve methods useful in the forensic practice.