Discriminant function sexing of fragmentary and complete tibiae from medieval Croatian sites

Previous studies have demonstrated that populations differ from each other in size and proportion and that these differences can affect metric assessment of sex. This paper establishes standards for determining sex from fragmentary and complete tibiae in the medieval Croatian population. The sample is composed of 180 tibiae (96 males and 84 females) from six medieval archaeological sites in Croatia. Three of the sites were located in continental Croatia, three on the eastern Adriatic coast and its immediate hinterland. Six tibial dimensions were measured: (1) length of the tibia; (2) maximum epiphyseal breadth of the proximal tibia; (3) maximum epiphyseal breadth of the distal tibia; (4) maximum diameter of the tibia at the nutritient foramen; (5) transverse diameter of the tibia at the nutritient foramen; and (6) circumference of the tibia at the nutritient foramen. Unifactorial and multifactorial analyses were performed on the collected data. Six discriminant functions were generated, one using six variables, two using two variables, and three employing one variable. Results show that complete tibiae can be sexed with 92.2% accuracy. Slightly lower accuracies (91.7 and 87.8%) were achieved using a combination of two variables, while functions employing one variable were accurate from 85.6 to 81.7%. The results of this study show that the medieval Croatian tibia is a good skeletal component for determining sex. Standardized coefficients of the discriminant functions generated in this study support the results of previous studies that found that breadth dimensions provide better separation of the sexes than length.     

Discriminant function sexing of fragmentary femur of South African blacks

When fragmentary and incomplete bones are all that are available to the forensic anthropologist for use in sex determination, non-metric and metric sex discriminating parameters that have been derived from complete bones may be of little use. In such circumstances, sex discriminating metric methods that are of specific application to fragmentary bones will be more useful. Since such studies have not been systematically carried out in bones of South African blacks, the aim of this study was to begin to provide such data. Two hundred and twenty left femurs of black South Africans were obtained from the Raymond A. Dart Collection of African Skeleton, School of Anatomical Sciences, University of the Witwatersrand, South Africa. Five variables from the upper end of the femur and three variables from the lower end of the femur were measured and subjected to univariate and multivariate discriminant function analyses. The vertical head diameter and the medial condylar length were most successful in sex identification from the upper and lower ends of the femur respectively. The combined variables were more useful than the use of variables individually. Discriminant function score equations were derived for individual and combined variables from the upper and lower ends of the femur of the South African blacks.     

Discriminant function sexing of the mandible of indigenous South Africans

South Africa currently has a high homicide rate. This results in a large number of unidentified bodies being recovered each year, many of which are referred to the forensic examiner. This situation has resulted in considerable growth of forensic anthropological research devoted to devising standards for specific application in South African medico-legal investigations. The standards suitable for Black South Africans now encompass a wide variety of skeletal elements (e.g. cranium, humerus, pelvis, femur, patella, talus, calcaneus), each with differing degrees of accuracy. Apart from a preliminary investigation of the Zulu local population, however, we note that there appears to be no established metric mandible discriminant function standards for sex determination in this population. The purpose of the present study is to undertake a comprehensive analysis of sexual dimorphism in the mandible of Black South Africans, incorporating individuals from a selection of the larger local population groupings; the primary aim is to produce a series of metrical standards for the determination of sex. The sample analyzed comprises 225 non-pathological mandibles of Black South African individuals drawn from the R.A. Dart Collection. Nine linear measurements, obtained from mathematically transformed three-dimensional landmark data, are analyzed using basic univariate statistics and discriminant function analyses. All of the measurements examined are found to be sexually dimorphic; the dimensions of the ramus and corpus lengths are most dimorphic. The sex classification accuracy of the discriminant functions ranged from 70.7 to 77.3% for the univariate method, 81.8% for the stepwise method, and 63.6 to 84% for the direct method. We conclude that the mandible is a very useful element for sex determination in this population.     

Discriminant function sexing of the calcaneus of the South African whites

The skull and some postcranial elements, such as the humerus, femur, and tibia, have been used in their intact states for sex determination in forensic and archaeological cases. But, in practice, these bones are often recovered in fragmented states, which render them unsuitable for use in sex determination. The calcaneus is a compact bone that is able to withstand high tensile forces. Some of its parameters have been used for sex determination in American whites and blacks (1) and Italians (2). This bone has not been used for sex determination in the South African white population. Therefore, the aim of this study was to assess the degree of sexual dimorphism of the calcaneus of the South African white population sample, derive discriminant function score equations for use in sex determination, and determine the level of accuracy of its sex-determining ability. Nine parameters were measured on each pair of 53 male and 60 female calcanei of known South African white skeletons, obtained by a random sampling technique from the Raymond A. Dart Collection of Human Skeletons, School of Anatomical Sciences, University of the Witwatersrand, Johannesburg. Basic statistic and discriminant function analysis was performed on the acquired data. The basic statistics showed that all measured parameters were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The average accuracy of sex classification ranged from 73 to 86% for the univariate method, 81 to 91% for the stepwise method, and 82 to 92% for the direct method. It is concluded that the calcaneus is useful for sex determination in the South African white population.     

Stature estimation from fragmentary femora: a revision of the Steele method

The skeletal remains presented to forensic anthropologists are often fragmentary. Previously described methods of estimating stature from segments of long bones have not proved satisfactory because of the difficulty involved in identifying the precise anatomical landmarks by which they are defined. This study represents an assessment of the feasibility of stature estimation from fragmentary femora. A sample of 200 males and females, blacks and whites (total sample = 800), was obtained from the Terry Collection. New regression equations for the estimation of maximum femur length and stature from three well-defined and easy-to-measure segments of the femur are presented. This technique represents an improvement over methods currently in use for estimating stature from femur fragments; the location of the anatomical landmarks and the accuracy of the prediction are enhanced. The applicability of these formulae to a modern forensic sample is addressed with regard to secular trends in stature increase and changes in body segment proportions.     

Stature reconstruction using fragmentary femora in South Africans of European descent

It is well documented that the intact femur has the highest correlation with stature and as such has been widely used in the derivation of regression equations for stature estimation. As intact femur is not always present for analyses in forensic cases, it has become necessary to derive regression equations for the estimation of stature from fragments of this bone. Few studies have presented regression equations for stature estimation from fragments of the femur. Because these equations are population specific, it was the aim of this study to derive similar equations for estimation of stature and maximum length of femur from measurements of the femur of South Africans of European descent. A sample of 50 male and 50 female complete skeletons were obtained from the Raymond A. Dart Collection of Human Skeletons. Total skeletal height for each of the skeletons was calculated using the Fully's method. Six variables were measured on each femur which included the vertical neck diameter, upper breadth of femur, epicondylar breadth, bicondylar breadth, lateral condyle length, and medial condyle length. Regression equations for the estimation of stature are presented. The range of standard error of estimate for these equations (3.71-5.31) was slightly higher than those obtained for intact long bones (2.13-3.79). It is therefore suggested that in the absence of intact femur, regression equations derived from the present study can provide a reliable estimate of adult stature.     

Discriminant function analysis for sex assessment in pelvic girdle bones: sample from the contemporary Mexican population

Sex assessment of skeletal remains plays an important role in forensic anthropology. The pelvic bones are the most studied part of the postcranial skeleton for the assessment of sex. It is evident that a population-specific approach improves rates of accuracy within the group. The present study proposes a discriminant function method for the sex assessment of skeletal remains from a contemporary Mexican population. A total of 146 adult human pelvic bones (61 females and 85 males) from the skeletal series pertaining to the National Autonomous University of Mexico were evaluated. Twenty-four direct metrical parameters of coxal and sacral bones were measured and subsequently, sides and sex differences were evaluated, applying a stepwise discriminant function analysis. Coxal and sacra functions achieved accuracies of 99% and 87%, respectively. These analyses follow a population-specific approach; nevertheless, we consider that our results are applicable to any other Hispanic samples for purposes of forensic human identification.     

Mandibular ramus: an indicator for sex in fragmentary mandible

Mandible is the hardest and most durable bone of the skull exhibiting a high degree of sexual dimorphism. Especially ramus of mandible is subjected to greater stress than any other bone of the skull because of the process of mastication. This study has been performed to establish the osteometric standards for practical use in forensic context over Indian population using mandibular ramus. The sample consists of 116 mandibles of Northern Indian population (M:F; 92:24, mean age 37.4 years), collected from the Department of Forensic Medicine, IMS, BHU, Varanasi. Osteometric informations about five metric parameters (coronoid height, projective height, condylar height, and maximum breadth and minimum breadth of ramus) were taken with sliding calipers. These parameters were subjected to different discriminant function analysis using SPSS 16.0. All parameters showed significant sexual dimorphism (p < 0.001 in all cases) with an overall accuracy of 80.2%, and coronoid height was the single best parameter providing an accuracy of 74.1%.     

Sacroiliac joint bridging: simple and reliable criteria for sexing the skeleton

Vital to the study of past populations and an important phase in executing a forensic anthropological examination is the determination of skeleton sex. The aim of this study is to present an easy and reliable criterion for sexing the skeleton. The ilium and sacrum of 2845 skeletons were examined for new bone formation and for bridging/fusion in/across the sacroiliac joint. Sacroiliac joint bridging (SIB) was present in 12.27% of the males and 1.83% of the females. In 97% of the males bridging was extra-articular, whereas in all females bridging was intra-articular. In addition, computed tomograghy images of 81 in vivo individuals were examined for the same phenomenon. SIB was present in 34.2% of the males and 4.6% of the females. Bony spurs present on the ilium for a preliminary partial or full extra-articular bridging of the sacroiliac joint indicate a male skeleton. SIB presents an easy technique for sexing skeletons (especially in elderly individuals where the phenomenon of SIB becomes very common), as no prior knowledge, training, or equipment is required to apply the criterion.     

A metric method for sex determination using the proximal femur and fragmentary hipbone

The pubic bone is considered one of the best sources of information for determining sex using skeletal remains, but can be easily damaged postmortem. This problem has led to the development of nonpelvic methods for cases when the pubic bone is too damaged for analysis. We approached this problem from a different perspective. In this article, we present an approach using new measurements and angles of the proximal femur to recreate the variation in the pubic bone. With a sample from the Terry Collection (n > 300), we use these new variables along with other traditional measurements of the femur and hipbone to develop two logistic regression equations (femur and fragmentary hipbone, and femur only) that are not population specific. Tests on an independent sample (Grant Collection; n = 37-40) with a different pattern of sexual dimorphism resulted in an allocation accuracy of 95-97% with minimal difference by sex.     

The sexing of bloodstains by testosterone: total protein ratio determination

A simple method for the extraction of testosterone from bloodstains followed by its measurement by radioimmunoassay is described. Complete discrimination of males and females was achieved with measured bloodstains as small as 40 microliters. With stains of unknown volume the total protein content of the stain was determined as an internal reference level. Using the testosterone/protein ratio unequivocal identification was possible for 75% of the stains from males and 50% from females.     

Sex assessment from carpals bones: discriminant function analysis in a contemporary Mexican sample

Sex assessment is one of the first essential steps in human identification, in both medico-legal cases and bio-archaeological contexts. Fragmentary human remains compromised by different types of burial or physical insults may frustrate the use of the traditional sex estimation methods, such as the analysis of the skull and pelvis. Currently, the application of discriminant functions to sex unidentified skeletal remains is steadily increasing. However, several studies have demonstrated that, due to variation in size and patterns of sexual dimorphism, discriminant functions are population-specific. In this study, in order to improve sex assessment from skeletal remains and to establish population-specific discriminant functions, the diagnostic values of the carpal bones were considered. A sample of 136 individuals (78 males, 58 females) of known sex and age was analyzed. They belong to a contemporary identified collection from the Laboratory of Physical Anthropology, Faculty of Medicine, UNAM (Universidad Nacional Autónoma de México, Mexico City). The age of the individuals ranged between 25 and 85 years. Between four and nine measurements of each carpal bone were taken. Independent t-tests confirm that all carpals are sexually dimorphic. Univariate measurements produce accuracy levels that range from 61.8% to 90.8%. Classification accuracies ranged between 81.3% and 92.3% in the multivariate stepwise discriminant analysis. In addition, intra- and inter-observer error tests were performed. These indicated that replication of measurements was satisfactory for the same observer over time and between observers. These results suggest that carpal bones can be used for assessing sex in both forensic and bio-archaeological identification procedures and that bone dimensions are population specific.     

Robots,standards and the law: Rivalries between private standards and public policymaking for robot governance

This article explains the complex intertwinement between public and private regulators in the case of robot technology. Public policymaking ensures broad multi-stakeholder protected scope, but its abstractness often fails in intelligibility and applicability. Private standards, on the contrary, are more concrete and applicable, but most of the times they are voluntary and reflect industry interests. The ‘better regulation’ approach of the EU may increase the use of evidence to inform policy and lawmaking, and the involvement of different stakeholders. Current hard-lawmaking instruments do not appear to take advantage of the knowledge produced by standard-based regulations, virtually wasting their potential benefits. This fact affects the legal certainty with regards to a fast-paced changing environment like robotics. In this paper, we investigate the challenges of overlapping public/private regulatory initiatives that govern robot technologies in general, and in the concrete of healthcare robot technologies. We wonder until what extent robotics should be governed only by standards. We also reflect on how public policymaking could increase their technical understanding of robot technology to devise an applicable and comprehensive framework for this technology. In this respect, we propose different ways to integrate the technical know-how into policymaking (e.g., collecting the data/knowledge generated from the impact assessments in shared data repositories, and using it for evidence-based policies) and to strengthen the legitimacy of standards.     

Discriminant analysis of the mandible for sex determination

Seventeen measuring parameters were used to characterize 197 mandibles (109 males, 88 females) taken from the corpses of people 20-80 years of age from the Rhine-Main-Neckar area. The representative measuring parameters and discriminating functions of intact lower jaws and lower jaw fragments of most frequent fracture types were determined in this practice group by means of discriminating analysis. In the present research material it was possible to determine sex accurately from an intact lower jaw bone in 82.6% (m) and 79.5% (f) of the cases. Furthermore, our results show clearly that sex may even be determined from lower jaw fragments. The classification was correct, depending on the type of fragment, in 72.5%-81.7% (m) and 71.6%-79.5% (f) of the cases.     

Testing the effectiveness of two cranial base foramina for metric sex assessment of fragmentary remains

Sex differences in linear and area dimensions of the foramen ovale and external opening of the carotid canal were analyzed in a documented French sample (35 men and 32 women). The results demonstrated that a low level of sexual dimorphism is present in the cranial base foramina of this sample, with only two-thirds of the examined variables exhibiting statistically significant differences (p < 0.05) between the sexes. The cross-validated sex classification accuracy rates obtained for univariate and multivariate discriminant functions ranged from only 54.7 to 72.1%. In addition, measurements of the cranial base foramina were found to be difficult to record with precision, with intra-observer error percentages ranging from 2.35 to 4.23%. Error rates of this magnitude may result in the misallocation of specimens. Therefore, osteometric analysis of the foramen ovale and carotid canal external opening cannot be recommended as a useful method for cranial sex assessment in this population group.     

A simple and inexpensive molecular method for sexing and identification of the forensic samples of elephant origin

The population of the Asian elephant is being dramatically reduced due to poaching of the ivory from the male. As poaching occurs in remote forests, it often takes weeks or longer for it to be discovered and it is therefore often very difficult to determine the sex of the decomposed body. Data suggest that in the recent past, over 2000 male elephants have been poached in South India. We have developed a technique based on molecular markers to determine that the carcass is an elephant and that it is a male. Using DNA sequence information from Genbank, we have developed two primer pairs: one for the mitochondrial DNA (mtDNA) and the other for the sex-determining region of Y chromosome (SRY) gene of the Indian elephant. After PCR amplification of known elephant DNA, we found that the mtDNA was common in both males and females, whereas the SRY-specific amplicon was observed only in the male.     

ASTM standards for fire debris analysis: a review

The American Society for Testing and Materials (ASTM) recently updated its standards E 1387 and E 1618 for the analysis of fire debris. The changes in the classification of ignitable liquids are presented in this review. Furthermore, a new standard on extraction of fire debris with solid phase microextraction (SPME) was released. Advantages and drawbacks of this technique are presented and discussed. Also, the standard on cleanup by acid stripping has not been reapproved.Fire debris analysts that use the standards should be aware of these changes.     

TEMPO: A contemporary model for police education and training about mental illness

Given the increasing number of interactions between police and people with mental illnesses (PMI), there has been widespread interest in the development of education for police about how best to interact with PMI. This paper reflects the review of current practice in a variety of jurisdictions across Canada as well as in the United States (U.S.), the United Kingdom (U.K.) and Australia; it proposes a comprehensive model of learning based on the literature that addresses not only the content in the narrow sense but also the importance of broader contextual knowledge and understanding in developing effective education and training. Embedded in the principles articulated in the Mental Health Strategy for Canada, the TEMPO (Training and Education about Mental illness for Police Organizations) model is a multilevel learning strategy for Canadian police personnel. Learning objectives and key principles are articulated in order to ensure the model is applicable to a wide range of police agencies and individual jurisdictional needs. In addition to providing a firm basis of factual knowledge for police personnel, the resultant model embraces a human rights/anti-stigma philosophy, provides for a range of education appropriate to diverse police audiences, emphasizes a systems approach to police/mental health liaison activities and addresses issues related to the delivery and implementation of police education and training.