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Biological evidence is often found at crime scenes and can comprise of DNA from the victim(s) and perpetrator(s) to a crime as well as from individuals with no direct relationship to the incident. This can complicate analysis as DNA mixtures are one of the more difficult sources of biological evidence to interpret. Probabilistic genotyping (PG) has greatly aided in mixture analysis. However, even with PG, standard bulk mixture approaches do not always result in probative results as allele overlap, artifacts, or low-level minor contributors inevitably cause genotype information loss. Therefore, deconvolution of forensic DNA mixtures into their individual component DNA (geno)types is of great investigative value. In the present work, enhanced single cell DNA typing conditions consisting of reduced reaction volumes and increased PCR cycle number were optimized and paired with a simplified micro-manipulation technique resulting in a subsampling scheme referred to as direct single cell subsampling (DSCS). Furthermore, the PG systems STRmixTM and EuroForMix were validated for use with both standard bulk DNA mixtures as well as with 1-5 cells. The DSCS approach was applied to various complex mixture scenarios including equimolar 2-6 person mixtures, mixtures comprised of 1st degree relatives, mixtures in which a minor donor is virtually undetectable (~1:50), and mixtures that had been deposited for varying time periods resulting in a probative gain of information compared to the standard mixture methods. Specifically, with the 5- and 6- person complex mixtures analyzed, DSCS recovered highly probative LRs ( > 10^20) from donors that had returned non-probative LRs ( < 10^3) by standard methods. With familial mixtures, DSCS prevented the false inclusion of non-donor relatives seen with standard methods. This approach was further applied to Y-STR mixture analysis. The DSCS approach could permit forensic scientists to analyze and recover probative evidentiary information from complex mixtures with excessive overlapping alleles such as those seen with related individuals and large contributor numbers as well as from mixtures with marginally detectable minor donors. Requiring only basic equipment and materials, the DSCS approach can easily be implemented into a casework laboratory.

Latent print evidence collected from crime scenes are analyzed and compared by examiners using the ACE-V protocol (Analysis, Comparison, Evaluation-Verification) to identify potential suspects. However, smudged and poor-quality prints, usually deemed inconclusive, could be utilized for source association or discrimination based on the chemistry of the oils and sweat that comprises the latent print residue (LPR). For this research, LPRs were collected from various places on the face and analyzed via two-dimensional gas chromatography-mass spectrometry (2D GC-MS), one-dimensional (1D) GC-MS, and direct analysis in real time-high resolution mass spectrometry (DART-HRMS). LPR recovery with two common sample preparation methods, derivatization and non-derivatization, was examined when collected on a porous and non-porous substrate. The method that provided high correlation and low relative standard deviation for each substrate was used for subsequent studies. Then, the LPRs were investigated to observe if association to a source can be achieved in either 1D or 2D GC. Comparison methods of Pearson correlation coefficient (PCC), principal component analysis (PCA), hierarchical cluster analysis (HCA), and receiving operating characteristic (ROC) curves were used to test source association. An aging study was performed to analyze the change in latent print chemistry when simulating evidence storage for up to three months via 1D GC and DART-HRMS. During this time, a longevity study was conducted by collecting LPRs every two weeks to test the intra- and inter-variability of the recovered chemistry. Correlation and similarity metrics such as PCC, Spearman's rank correlation, and Euclidean distance were used to compare the monthly and weekly changes of the LPRs.

This thesis explores the extent to which forensic archaeology and forensic anthropology are utilised within Great Britain and to what extent they aid, or do not aid, medico-legal investigation of death. Chapter One introduces the topic and considers the need for an exploration of these issues. In Chapter Two, the differences between the American and British situations are examined and an explanation for the differences proposed, based on the development of the academic ‘parent’ disciplines during the last century. Chapter Three explores issues around accreditation and registration in the UK. The role of the courts in maintaining standards of expert evidence is examined. National and European schemes are considered. After considering the practitioners in this way, Chapter Four looks at the methods, and how the practitioners’ experience informs their choice of method. One specific topic for each discipline is discussed in depth and the complexity of choice illustrated. The difficulty in assessing the full scope for use of forensic archaeology and forensic anthropology are detailed in Chapter Five, with the marked lack of available research data. The problems inherent in media-derived data are considered. The scope for use of the two disciplines is discussed and illustrated with examples from the Media Derived Case List In Chapter Six, a complex multiple-burial multiple-murder case is discussed; and interviews across one police force area are discussed. These illustrate the use and usefulness of forensic archaeology in practice. Conclusions are drawn in Chapter Seven, and radical recommendations are made.

Thesis (DPhil) (Sociology and Social Anthropology))--University of Stellenbosch, 1967.

Secular change has been documented in a number of studies focused on cranial and postcranial morphometrics and nonmetric traits. However, to date, few studies have addressed the potential of temporal change occurring in the expression of cranial nonmetric traits utilized in ancestry estimation. This study examines the effect of secular change on the expression of 23 cranial and mandibular nonmetric traits frequently employed in ancestry estimation; with age-at-death, sex, and year-of-birth of each individual documented for data analysis. Data were collected from European American individuals from the Hamann-Todd Skeletal Collection (n=518) and from the William M. Bass Donated Skeletal Collection (n=602). Individuals were divided into birth-year cohorts as follows: Hamann-Todd Skeletal Collection: 1824-1849 (Cohort 1), 1850-1874 (Cohort 2), 1875-1899 (Cohort 3), and 1900-1924 (Cohort 4); William M. Bass Donated Skeletal Collection: 1900-1924 (Cohort 4), 1925-1949 (Cohort 5), and 1950-1987 (Cohort 6). Pearson’s chi-square analyses produced significant p-values (≤ 0.01) in 19 of the 23 traits between the six birth-year cohorts. Factor maps generated through correspondence analyses were used as visual representations of relative trait expression between the cohorts. Ordinal regression analyses assessed the degree of variation between each cohort in relation to Cohort 1 along with the influence of age-at-death and sex on trait expression. Overall, analyses of the data revealed that secular change has occurred in 11 of the 23 traits, including: anterior nasal spine (ANS), malar tubercle (MT), nasal bone contour (NBC), postbregmatic depression (PBD), supranasal suture (SPS), transverse palatine suture (TPS), zygomaticomaxillary suture (ZS), gonial angle flare (GAF), mandibular tori (MDT), and posterior ramus edge inversion (PREI). Change in trait expression occurred in both males and females in seven traits, including: ANS, MT, TPS, ZS, GAF, MDT, and PREI. Significant change in trait expression occurred predominately between Cohorts 3 and 4 (birth years ranging from 1875 to 1924) and Cohorts 4 and 5 (birth years ranging from 1900 to 1949). This study demonstrates that secular change in nonmetric cranial and mandibular traits has occurred over the last two centuries with the greatest change appearing at the turn of the twentieth century.

When considering what packaging material is optimal for a piece of biological evidence there are two vital things to consider: degradation and contamination (1). Biological evidence collected from a crime scene is brought to the laboratory, however, immediate testing upon arrival is highly unlikely (2). Therefore, the packaging must be suitable for transportation as well as storage. During the storage phase, if improper packaging is utilized, degradation and/or contamination could occur. General forensic practice is to dry biological samples before packaging, then package the evidence in a paper (breathable) container. This study investigated the use of kraft stock envelopes, plastic bags, glassine envelopes, Tyvek envelopes, evidence/syringe tubes, knife pouches, and Cap-Shure® plastic swab caps to package wet blood and semen samples. The packaging materials were evaluated in a humidity study, degradation study, and transfer study to determine if the biological specimen would remain intact and contained within the packaging. In the humidity study, it was determined that the kraft paper, glassine paper, and Tyvek® allowed for the passage of moisture, enabling the enclosed sample to readily dry. The plastic bag, evidence tube, and knife pouch created a difference in relative humidity above 20%, thus increasing the ambient moisture concentration the samples were exposed to. In the degradation study, all samples were positive for their respective biological substance when tested with screening, presumptive, and confirmatory methods, however, bacteria were observed on samples that were packaged in plastic bags evidence tubes, and plastic caps. Additionally, only one sample, packaged in an evidence tube, yielded a DNA degradation index that implied degradation had occurred. The packaging materials were also tested to determine if the biological fluid would transfer through them, permitting cross-contamination. The kraft paper and one glassine paper did not provide a true barrier, as blood transferred through the envelopes onto a surrounding surface. The Tyvek®, knife pouch, and plastic bag all kept the wet blood contained within the package and no transfer to the surrounding surfaces occurred, although bloodstains on the interior of the Tyvek® and knife pouch could be visualized from the exterior. Overall, Tyvek® envelopes were determined to be an optimal packaging material for wet biological samples when compared to the other packaging materials used in this limited study due to their relative strength, ability to allow fluids to air dry and the lack of penetration of wet blood to the exterior surface.

Of the 206 bones that compose an adult skeleton, only a select few are used in the estimation of sex and age. The best indicator of the sex of an adult skeleton is derived from several morphological features of the pelvis. In addition to the pelvis, characteristics of the sacrum, long bones, and skull have been used to estimate sex in adult remains. The most accurate indicators of age-at-death at the present time are related to features of the pubic bone, the auricular surface of the ilium, and the sternal end of the fourth rib. The current project assesses the utility of the sternum for estimating age and sex using two current methods. The two methods in question are those of Bongiovanni and Spradley (2012) for the estimation of sex and Sun et al., (1995) for the estimation of age. The data gathered at the Robert J. Terry Anatomical Skeletal Collection for this study is used to assess the validity and accuracy of the two different methods utilizing a North American population differing from that of Bongiovanni and Spradley (2012). Results showed a high congruence with the results of Bongiovanni and Spradley (2012) in which an overall classification rate of 81.1% was achieved. The cross-validation classifications for males and females were 79.9% and 83.6% respectively and an overall classification rate of 86.7% was achieved using total sternal length (TL). Results also demonstrate that the mean values of sternal index conform to Hyrtl's Law, however the range of values largely overlap, and demonstrates the law's unreliability for sex estimation. Results showed a lack of congruence with the Sun et al., (1995) method reaching a classification rate for exact age estimates of 14.4%. Overall, the utility of the human sternum for sex estimation seems promising and practically simple. The utility of the human sternum for age estimation merits further research into methods that might provide higher classification rates, however, at this time no methods seem worthwhile.

Introduction: Forensic pathologists may be asked to identify the race group or sex of a cranium of unknown origin. Race group refers to geographic ancestry and sex is biological sex. An analysis of the volumes and measurements of human paranasal sinuses, namely maxillary, ethmoid, sphenoid and frontal sinuses, in dried crania of different race and sex groups (European and Zulu male and female) was undertaken to search for a new improved approach of classifying crania according to race and sex. This anatomical assessment of the human paranasal sinuses identifies race and sex variations in the paranasal sinuses. Variations in paranasal sinus volumes and measurements may mean a variation in anatomical landmarks. The best combination of sinus measurements was selected to classify a cranium according to race group and sex making this research relevant to the field of forensic medicine. Objectives: To compare the paranasal sinus volumes and measurements of dried crania of European and Zulu descent with respect to race group and sex and to develop a method of classifying a cranium according to race group or sex by using dimensions of the paranasal sinuses. Methodology: Documented, cadaver derived, dried crania were obtained from the Raymond A. Dart Collection of Human Skeletons, housed at the School of Anatomical Sciences at the University of the Witwatersrand, Johannesburg, South Africa. Age, race and sex were recorded for each cranium within the collection and hence within the study sample. 26 Adult European crania; 13 male, 13 female. Age range 19-75yrs (mean 49.42yrs) and 27 Adult Zulu crania: 13 male, 14 female. Age range 16-90yrs (mean 40.16yrs) was selected for this study. An additional cranium of unknown origin was also analysed in the research. European crania were from descendants of Europe living in South Africa and Zulu crania were obtained from Zulu patients who were part of the Zulu tribe of South Africa. 53 crania with intact paranasal sinuses (106 individual sinuses for each of the maxillary, ethmoid, sphenoid and frontal sinuses) were studied. In addition, 2 sinuses from the unknown cranium were analysed. The dried crania of European and Zulu origin were assessed by helical, multislice computed tomography using 1mm coronal slices. The area for each slice was obtained by tracing the outline of each slice. A volume was calculated by the CT machine that totaled the slices for each sinus. Measurements of width, length and height were also assessed, as were other craniometrical measurements. Statistical analysis was performed for all European and Zulu male and female sinuses in respect of volumes and measurements. Further statistical analysis searched for classification patterns. In addition, forty patients' scans from the European and Zulu male and female groups in Southern Africa were also assessed. CT scans of 10 adult European males, 10 adult European females, 10 adult Zulu males and 10 adult Zulu females provided 40 pairs of maxillary, ethmoid, sphenoid and frontal sinuses for analysis. Europeans were South African persons of European descent and Zulus were from the Zulu tribe of Kwa Zulu Natal in South Africa. Results: The aim of identifying race and sex differences in this anatomical region is achieved. Significant race and sex variations were found in the European and Zulu, male and female groups when analysing the volumes and measurements of the paranasal sinuses. The very best combinations of classifiable measurements were described and are being put forward as a new tool in human forensic identification studies. The significant sex classification figure of 91.8% by combining ethmoid, sphenoid and frontal paranasal sinus measurements, is a new discovery for using a combination of the sinuses. The significant race classification figure of 95.9 % is an excellent classification figure for classification according to race. This was done using the measurements of maxillary, ethmoid and total distance across the sinuses. All this was achieved by using the measurements of the paranasal sinuses in a European and Zulu, male and female population. Conclusion: Forensic race and sex identification of crania is now possible using a combination of measurements from the paranasal sinuses. A new approach to classifying a cranium into an race or sex group is revealed by way of using a new combination of paranasal sinus measurements. This discovery is of importance to forensic medicine in the realm of identification as it provides a measurable way of assigning race or sex to a cranium within a particular region. Other studies based on other race groups may add further value. What is clear is that the paranasal sinuses are now of established value when assessing race or sex group of a unknown cranium. A new tool for forensic race and sex identification is provided to the armamentarium of the forensic pathologist and associated disciplines.