Forensic Applicability of Femur Subtrochanteric Shape to Ancestry Assessment in Thai and White American Males

Ancestry assessment from the postcranial skeleton presents a significant challenge to forensic anthropologists. However, metric dimensions of the femur subtrochanteric region are believed to distinguish between individuals of Asian and non‐Asian descent. This study tests the discriminatory power of subtrochanteric shape using modern samples of 128 Thai and 77 White American males. Results indicate that the samples' platymeric index distributions are significantly different (p ≤ 0.001), with the Thai platymeric index range generally lower and the White American range generally higher. While the application of ancestry assessment methods developed from Native American subtrochanteric data results in low correct classification rates for the Thai sample (50.8–57.8%), adapting these methods to the current samples leads to better classification. The Thai data may be more useful in forensic analysis than previously published subtrochanteric data derived from Native American samples. Adapting methods to include appropriate geographic and contemporaneous populations increases the accuracy of femur subtrochanteric ancestry methods.     

Population variation in femur subtrochanteric shape

Use of proximal femur shape to determine ancestry has appeal, but its validity is problematic because of unaddressed issues associated with skeletal plasticity, within- and between-population variation, sample selection, and interobserver error. In this paper, I inspect within- and between-group variation in proximal femur shape using five groups (American Blacks, American Whites, Hispanics, Native Americans, and Polynesians), and examine the affect of three environmental variables (subsistence strategy, physical terrain, and geographical region). Finally. I consider the validity of using the proximal femur to assess ancestry. The results show that there is significant within-group variation in proximal femur shape. Among Native Americans, both geographical location and subsistence strategy have a significant affect on proximal femur shape. Nevertheless, this study generally verifies the assertion that the proximal femur can be used reliably to distinguish Native Americans from American Blacks and Whites, but its precision may be reduced in some geographical regions.     

Size and Shape Differences in the Distal Femur and Proximal Tibia between Normal Weight and Obese American Whites

This study tests for differences in articular and diaphyseal size and shape of the distal femur and proximal tibia between normal weight and obese individuals, and discusses the effects of obesity on the patterns of sexual dimorphism and secular change in the skeletal morphology of the knee. Measurements of the femur and tibia were recorded for 143 American White adult males and females born in the 20th century. The sample was divided into normal and obese weight categories based on the body mass index. Results show differences between normal weight and obese individuals in the size and shape of the femoral shaft and the medial side of the knee joint, none of which affect the pattern of sexual dimorphism. While changes in skeletal morphology associated with obesity may be observed in recent secular changes, its role is still unclear because of the relatively recent increase in obesity prevalence.     

Evaluation of Purkait's triangle method for determining sexual dimorphism

The identification of sex from the skeleton is an important demographic assessment in medicolegal investigations. Rama Purkait developed a method for estimating sex using measurements from a triangle defined by three points on the proximal end of the femur using skeletal material from Bhopal, India. This method was tested with measurements on 200 Indo-European and African American adult femora from the Terry collection using discriminant function analysis to determine if Purkait's method was valuable for determining sex in Americans. A side-by-side analysis was conducted of Purkait's "triangle method" and the maximum diameter of the femoral head to determine their relative value in assessing sexual dimorphism. In the study sample a single variable from Purkait's method provided 85.5% prediction accuracy, similar to 87% for the head diameter. Combining threshold values for a single variable from Purkait's method and the femoral head diameter raised the predictability to greater than 90% for both sexes.     

利用中国汉族成人股骨上端CR片特征判定年龄

目的探讨中国汉族成人股骨上端CR片的特征随年龄变化的规律,以推断年龄。方法 277例中国汉族成人骨盆正位CR片,其中男性139例,年龄范围18-83岁,女性138例,年龄范围18-85岁,选取股骨上端的股骨头、股骨颈、大转子内的骨小梁及股骨上端髓腔高度四项指标,观察不同年龄各指标的变化进行统计分析。结果成人股骨头、股骨颈骨小梁变化和股骨上端髓腔高度是影响45岁以下年龄变化的重要因素,股骨大转子影响较小。四项指标对45岁以上年龄组均是影响年龄变化的重要因素。利用以上指标建立的回归方程能很好的反映成人股骨上端的增龄性变化,预测骨龄较为准确。结论利用成人股骨头、股骨颈、股骨大转子内骨小梁的改变及股骨上端髓腔高度变化可推断年龄。     

The Use of Femoral Neck Axis Length to Estimate Sex and Ancestry

Having multiple reliable methods of estimating sex and ancestry from various skeletal features increases the likelihood of identifying skeletal remains. Femoral neck axis length (FNAL), as measured in living individuals, has been shown to vary by sex and ancestry. FNAL has not, however, been previously measured directly from skeletonized remains and investigated for its potential use in forensic anthropological applications. This research proposes a method for measuring FNAL from skeletal remains, determines the reliability and repeatability of the measurement, and assesses the validity of FNAL in sex and ancestry estimation. Results showed low interobserver error in the measurement of FNAL (TEM = 0.33 mm, R = 0.99). Significant differences in FNAL were found between sexes as well as between American Black, American White, and Native American groups. FNAL can correctly classify sex in ~86% of all cases and is considered valuable to sex estimation. The value of FNAL to ancestry estimation, however, is considered limited.     

The correctional melting pot: Race, ethnicity, citizenship, and prison violence

The United States prison population is becoming more diverse and comprised of increasingly more violent inmates. Although race has been cited as a risk factor for inmate violence, most prior research had narrowly investigated White/Black differences in inmate misconduct. Using a sample of 1,005 inmates from the southwestern U.S., the current study explored racial, ethnic, and citizenship correlates among male and female prisoners. Negative binomial regression models indicated that net of controls, Hispanics and Native Americans were the most violent male prisoners, while African Americans and Native Americans were the most violent female inmates. The current study was admittedly modest in scope; however, the findings were couched within a broader, imperative sociological framework that lamented the increasing interplay between communities and prison and the role of prison as a social institution.     

A Quantitative Assessment of Zygomatic Projection for Ancestry Estimation

Anterior zygomatic projection (ZP) is historically referenced as a useful trait in ancestry estimation, particularly when differentiating between Native Americans and U.S. Whites and Blacks. However, methods of assessing ZP vary, are susceptible to multiple interpretations, and have not been quantitatively validated. This study uses 228 3D surface scans of U.S. Whites, U.S. Blacks, and Native Americans to quantitatively test the ZP methods published by Rhine in 1990 (Skeletal attribution of race: methods for forensic anthropology, Albuquerque, NM, Maxwell Museum of Anthropology, 1990) and Bass in 1995 (Human osteology: a laboratory and field manual, Columbia, MO: Missouri Archaeological Society, 1995). Two ZP angles and two distances, representing method interpretations, were collected and analyzed via ANOVA and discriminant function analyses. Although significant ancestry differences were found across all variables, only the Bass inferior zygomatic distance successfully differentiated the pooled Native American group from pooled U.S. Whites/Blacks (73.7% correct). Arctic Native Americans, displaying the most projecting zygomas, are driving group differences. Significant overlap in measurement distributions were observed between groups in all variables, indicating limited forensic utility.     

Racial variation in the proximal and distal femur: heritability and forensic utility.

The femur has been studied successfully by physical anthropologists for many years. Such traits as femoral head diameter and bicondylar width have been examined extensively and are of great value to forensic anthropologists and other skeletal biologists in sex identification. A number of studies over the past decade by the author and his former students have shown marked racial differences in the shape of the proximal femur and in at least one trait of the distal femur--intercondylar notch height. Anterior-posterior (AP) diameter of the proximal femur is much greater among Whites and Blacks than among East Asians and American Indians. Blacks have slightly greater intercondylar notch height than Whites. Other features, such as torsion, also differ between the major geographic racial populations. Current analysis suggests that the East Polynesians fall close to the American Indians and East Asians in the degree of flatness of the proximal femur. One study has tracked the degree of change in flatness during individual development, and finds little change within major populations from the youngest to the oldest individuals. Temporal changes within populations are likewise minimal. Two studies have examined sex differences within populations, which are also found to be very slight. Racial differences, on the other hand, are quite significant, and individuals of admixed ancestry fall intermediate between the two parental populations. Such suggestions of high heritability in the shape of the proximal and distal femur make these traits very useful in assessing ancestry in forensic contexts.     

The Attitudes of Minority Inmates Towards Recreation Programs As a Rehabilitative Tool

The purpose of this study was to determine the attitudes of three Oregon State Penitentiary minority inmate groups—Blacks, Hispanics and Native Americans—towards the Recreation program as a rehabilitative tool. Two other purposes were to (1) determine significant differences among group attitudes, and (2) determine the degree to which each group accepted/rejected rehabilitation achievement. A survey questionnaire of fifty items representing rehabilitation achievement in three areas (program management, facility/equipment provision, and habits/participation) validated by Delphi technique, was utilized. A one-way ANOVA was applied for data analysis and hypothesis testing. Where significance was achieved at the .05 level or beyond the Student-Newman-Keuls' post-test was used. The Chi-Square technique was also used to determine the degree of rehabilitation achievement among the three groups. Findings regarding rehabilitation achievement indicated that (a) Black attitudes were significantly different from Native American and Hispanic attitudes through program management, (b) Blacks' attitudes were significantly different from Native Americans through facility/equipment provision and (c) Black and Hispanic attitudes were significantly different from Native Americans through personal habits/participation. The concept of rehabilitation achievement for the recreation program was rejected by Hispanics and Native Americans while Blacks were evenly split in their responses.     

A study of sexual dimorphism in the femur among North Indians

Determination of sex of unknown skeleton remains is the most important step in the identification process. Racial and regional differences in the populations create and maintain specificity in their dimorphic characteristics. Moreover, considering continued secular changes in the population structure, constant revision of osteometric standards becomes mandatory. In an effort to establish osteometric standards for the femur of contemporary North Indian populations, 122 adult femora of known sex (M: 94; F: 28) were collected in the Department of Forensic Medicine, IMS, BHU, Varanasi. Eight standard parameters were measured and analyzed by discriminant function analysis using SPSS 16. The accuracy of sex prediction ranged from 70.5% to 83.6% with single variables. In stepwise analysis, epicondylar breadth, proximal breadth, and antero-posterior diameter of the lateral condyle were found to be the most discriminating variables providing an accuracy of 90.2%. The results clearly indicate the importance of the ends of femur in the determination of sex.     

A comprehensive regression tree to estimate body weight from the skeleton

The purpose of this research is to estimate actual body weight (in particular obesity) from the human skeleton. Known individuals (total n=187) were studied from the Bass Collection from the University of Tennessee, Knoxville. This research combines bone density, cross-sectional geometry of the femur and skeletal pathologies. Bone mineral density was calculated for the proximal femur. Three-dimensional bone surface models were created from computed tomographic scans. Cross-sectional geometry of the femur was calculated at five locations along the diaphysis. The pathologies analyzed were heel spurs, diffuse idiopathic skeletal hyperostosis (DISH), and tibial osteoarthritis. The best regression tree model included only four variables. The first split to estimate body weight was the minimum moment of inertia (I(y) ) at the distal femur, the second was midshaft width, then anteroposterior thickness at the proximal slice and the final split was the degree of DISH (SD 17.1-31.0 kg). The ability to estimate body weight from the skeleton is one more useful tool for the osteologist.     

The impact of race on criminal justice ideology: An examination of high school students

Research suggests that differences exist in the criminal justice ideology of Black and White Americans. For example, adult African Americans are more likely than their White counterparts to support criminal justice measures that address the root causes of crime. There has, however, been limited interest in exploring the criminal justice ideology of juveniles. Using survey data collected from 1,398 rural and suburban public high school students, the present study examined the influence of race on the criminal justice ideology of juveniles. The findings suggested that while Black teenagers are significantly more likely to hold a liberal crime control ideology and White teenagers are significantly more likely to hold a conservative ideology, confidence in the justice system to be fair strongly influences the beliefs of both groups.     

Use of bone trabeculae to establish positive identification

Radiographic examination of 42 adult distal left femora and 38 proximal left tibiae revealed that no two bones were identical in the pattern and appearance of the trabeculae. In each case, a minimum of four distinct osseous features was easily visible on radiograph. The results indicate that radiolucencies and radiodensities in the distal femur and proximal tibia are valid individualizing features for establishing a positive personal identification in human remains.     

Race and Officer Decision Making: Examining Differences in Arrest Outcomes between Black and White Officers

Since the 1960s, one of the major reform efforts in law enforcement has been to increase the number of Black Americans within police agencies and on patrol in the streets. The general premise behind these efforts has been that increased diversity will improve police–community relations and will decrease biased police behavior, particularly against Black citizens. Policies seeking to reform policing through increasing the numbers of African American officers have been implemented with little empirical evidence that an officer's race (or ethnicity) is actually related to their behavior towards citizens, in particular arrest decisions. Using data from systematic social observations of police–citizen encounters in Cincinnati, OH, this study examines the influence of officer race on arrest outcomes, focusing on the behavior of Black officers. Findings suggest that officer race has direct influence on arrest outcomes and there are substantive differences between White and Black officers in the decision to arrest. In general, White officers in our study were more likely to arrest suspects than Black officers, but Black suspects were more likely to be arrested when the decision maker was a Black officer.     

应用膝关节MRI T_2加权脂肪抑制像推断活体年龄

目的探索膝关节MRI T2加权脂肪抑制像(T2-FS)在法医年龄推断中的应用价值,建立安全可靠的四川汉族年龄推断方法。方法收集膝关节MRI 324例(男性170例,女性154例),年龄范围为10~30岁。采用西门子1.5T磁共振仪摄片,MRI参数:T2-FS TSE序列,矢状位。将股骨远端、胫骨近端骨骺发育分为6个等级并赋分,分析各指标性别差异及年龄相关性,建立年龄推断回归模型。结果男女性股骨远端、胫骨近端MRI等级与年龄呈正相关性,股骨远端与年龄的相关性男性0.687,女性0.661;胫骨近端与年龄的相关性男性0.684,女性0.488。股骨远端骨骺完全闭合,骺线消失的最小年龄男性18.42岁,女性19.36岁;胫骨近端男性骺线消失的最小年龄为16.93岁,女性为14.68岁。股骨远端等级1~3、5、6和胫骨近端等级1~3、5年龄分布性别差异不显著。分别建立男女年龄推断模型,男性年龄推断平均绝对误差(MAD)=2.90岁;女性年龄推断MAD=3.30岁。结论膝关节MRI T2-FS影像可作为活体年龄推断的指标之一,股骨远端等级6可作为判断18岁的指标之一。     

四川省阿坝地区藏族青少年膝关节骨发育趋势

目的探讨四川省藏族青少年膝关节骨发育趋势,更新利用膝关节骨龄推断我国藏族青少年活体年龄的数据资料。方法在我国四川省阿坝地区调查483例14~19周岁藏族男、女性青少年膝关节X线片,选取股骨远端、胫骨近端及腓骨近端骨骺作为骨骼发育指标,观察骨骺发育情况,并运用SPSS 16.0统计学软件计算出青少年膝关节骨骺闭合年龄的描述性数据。结果膝关节中,闭合最早的骨骺是股骨远端骨骺,闭合最晚的是腓骨近端骨骺,其中女性青少年膝关节骨骺发育较男性提前约1岁左右。结论应用于法医学活体骨龄鉴定的藏族青少年相关数据资料应定期更新。本研究结果可为法医学、人类学及临床医学等相关学科在进行骨龄评价时提供参考。     

REASSESSING TRENDS IN BLACK VIOLENT CRIME, 1980–2008: SORTING OUT THE “HISPANIC EFFECT” IN UNIFORM CRIME REPORTS ARRESTS,NATIONAL CRIME VICTIMIZATION SURVEY OFFENDER ESTIMATES,AND U.S. PRISONER COUNTS*

Recent studies suggest a decline in the relative Black effect on violent crime in recent decades and interpret this decline as resulting from greater upward mobility among African Americans during the past several decades. However, other assessments of racial stratification in American society suggest at least as much durability as change in Black social mobility since the 1980s. Our goal is to assess how patterns of racial disparity in violent crime and incarceration have changed from 1980 to 2008. We argue that prior studies showing a shrinking Black share of violent crime might be in error because of reliance on White and Black national crime statistics that are confounded with Hispanic offenders, whose numbers have been increasing rapidly and whose violence rates are higher than that of Whites but lower than that of Blacks. Using 1980–2008 California and New York arrest data to adjust for this “Hispanic effect” in national Uniform Crime Reports (UCR) and National Crime Victimization Survey (NCVS) data, we assess whether the observed national decline in racial disparities in violent crime is an artifact of the growth in Hispanic populations and offenders. Results suggest that little overall change has occurred in the Black share of violent offending in both UCR and NCVS estimates during the last 30 years. In addition, racial imbalances in arrest versus incarceration levels across the index violent crimes are both small and comparably sized across the study period. We conclude by discussing the consistency of these findings with trends in economic and social integration of Blacks in American society during the past 50 years.     

Estimating sex of the human skeleton based on metrics of the sternum

Estimating the sex of skeletal remains is critical in creating the biological profile of an adult individual. Previous research has shown that analyzing the sternum may lead to an accurate estimation of sex based on studies performed on various populations around the globe, such as Indian, European, African, Canadian and North American. The motivation of the current study is to develop classification functions and sectioning points for use in forensic investigations in the United States. The majority of previously published methods are population specific, meaning the data would not prove useful in the United States. For this study, sternal measurements were collected from the William M. Bass Donated Skeletal Collection located at The University of Tennessee, Knoxville following the metric definitions provided by Schwartz and Bass. This collection consists of recent skeletal remains with known age at death, ancestry and sex. Material for the present study consisted of 410 human sterna: 285 male (256 American White/29 American Black) and 125 female (120 American White/5 American Black). Previous studies analyze the applicability of Hyrtl's law in the estimation of sex. This law follows that the mesosternum is greater than twice the length of the manubrium in males and in females the length of the manubrium is greater than half the length of the mesosternum. In this study, comparisons of the proportion of the length of the manubrium to the length of the mesosternum were performed to determine if Hrytl's law is applicable in an American population. Comparisons of these measurements between individuals identified as American Black and American White were analyzed to determine whether this method could be used on both population groups. Further, discriminant function analysis was used to estimate sex and provide a population specific classification function for use in the United States. The discriminate function analysis produced an overall cross-validation classification rate of 84.12% for sex estimation. The cross-validation classification rate for males and females was 80.00% and 88.24%, respectively.