Thesis (M.A.)--Texas State University--San Marcos, 2009. / Vita. Appendix: leaves 28-40. Includes bibliographical references (leaves 41-43). Also available on microfilm.

Thesis (M.A.) -- University of Tennessee, Knoxville, 2005. / Title from title page screen (viewed on Feb. 2, 2006). Thesis advisor: Lee Meadows Jantz. Vita. Includes bibliographical references.

Age-at-death estimation is a key component of creating a biological profile in forensic and bioarchaeological contexts, and the development of methods that utilize different skeletal elements or observe traits in a new manner are an important part of progress in the study of forensic anthropology. Use of the acetabulum for identifying age-at-death is among new methods being developed, and the recently published method by Calce (2012) was the focus of the present study. The present author analyzed a sample of 489 modern American individuals drawn from the William M. Bass Donated Skeletal Collection housed at the University of Tennessee and assigned each individual to a phase described by Calce (2012). The results of the present study show that use of this method correctly classified age-at-death 62.2% of the time. The performance of this method is low compared to the results of the initial study where Calce (2012) found the method to be 81% accurate. This suggests that the acetabulum is not as beneficial as an age-at-death indicator as previously considered, and that more research on the utility of the acetabulum as an age indicator is required.

Ancestry estimation for Hispanic Americans is increasing in importance as this minority population increases in the United States. Hispanics are historically an admixture of various geographic populations including European, Native American, and African. This combination of genes has caused many intermediate skeletal features that make identification of Hispanics a complicated process, especially when compared to Native Americans. "Hispanic" cannot efficiently encompass, as a term, the genotypic composition of multiple populations, as Hispanics from the Southwestern United States are historically a combination of Native American and European genes, whereas those from the Caribbean are historically an admixture of Native American, European, and African genes. While each of these regions can exhibit a certain combination of all three of these ancestral populations, each region has experienced a characteristic frequency of admixture. Southwest Hispanic populations are genotypically and phenotypically primarily comprised of Native American and European genes, resulting in an intermediate skeletal composition that prevents the distinct ancestry discrimination attainable by broad geographic groups. Previous dental morphological studies (Edgar 2013) have also presented results of intermediacy and particular difficulty separating these individuals from Native American and Asian groups; however, metric studies of the dentition of this population have yet to be investigated. Data were collected from n=569 dental casts from the James K. Economides collection which is housed at the Maxwell Museum in Albuquerque, New Mexico. Measurements included were the mesiodistal and buccolingual dimensions of the polar teeth of the morphogenetic field theory and the width and depth of the mandibular and maxillary arches. The morphogenetic field theory, as developed by Butler (1939) and adapted by Dahlberg (1945), represent the most stable teeth of the four fields of the dentition - incisors, canines, premolars, and molars. These "polar" teeth exhibit the least variation in crown size and shape. Significant differences were identified between ancestry groups and these were subsequently used to identify allocation rates between all groups and between particular sets, or groups, of ancestries. Discriminant function equations were developed as a tool for ancestry estimation. Success was greatest when both dental crown and arcade variables were pooled together in an analysis. Results of this study indicate odontometric analyses are useful in differentiating between Native Americans and European Americans, with classification rates ranging between 75.2% and 86.3%; however, much work must be conducted before application on Hispanic populations is possible. The Southwest Hispanic population exhibited greater phenotypic similarity to the European American population and had significantly lower success in allocation than between Southwest Hispanics and Native Americans. In cases where sex was known, successful allocation decreased, although females generally exhibited greater success than males. Potential utility is observed in this study when sex is unknown, and the development of a statistical methodology utilizing the dentition is proposed.

Multi-isotopic approaches have been used effectively to help provide estimated geographic origins for unidentified skeletal remains in cold case homicides and archaeological contexts, when DNA testing was not practical. Stable oxygen and strontium isotopes were used in the present study in order to determine their effectiveness of proveniencing human remains from Colombia and New England. Enamel hydroxyapatite was extracted from individual teeth (n=151) from individuals with known birthplaces for different regions of Colombia as well as the region of New England in the United States. All oxygen data is presented as a ratio of δ18O /δ16O (‰PDB). The results show significant geographical differences (p ≤ 0.001), between the Colombian and New England populations. The mean δ18O value for Colombia is -11.06 ± 1.28. The mean 87Sr/86Sr value for Colombia is 0.707391 ± 0.0016. The mean δ18O value of the samples from the United States is -7.42 ± 1.39. The mean 87Sr/86Sr value for the samples from the United States is 0.7099747 ± 0.0011. The oxygen and strontium ratios of the sample set have no significant differences within each geographic region. Additionally, a small subset of the immigrant community in Boston, MA is represented within the sample. There is a significant difference (p ≤ 0.002) in the population’s mean δ18O values. The establishment of this oxygen and strontium isoscape has the potential to provenience unidentified human remains recovered as a result of Colombia’s long-term internal conflict.

In forensic contexts, eliminating the ability for identification and/or discovery of victims is a priority for many individuals perpetrating a homicide. This can be achieved in a number of ways, but a common belief is that acidic products can accomplish both. The current study submerged twelve complete pig (Sus scrofa) heads in three different commercial products containing hydrochloric or sulfuric acid (n=4 for each product) in order to determine if complete liquefaction was possible. The product with 31.45% concentration of hydrochloric acid was able to liquefy each head in five days. Motor vehicle battery acid (37% concentration of sulfuric acid) was able to liquefy each head in five weeks. The product with the low concentration (5 – 10%) of hydrochloric acid was not able to remove the soft tissue, but did affect the structure and consistency of the bones and teeth. Some common chemicals therefore are effective tools in body disposal.

As forensic techniques employed in homicide investigation are refined, so are the methods by which perpetrators of these crimes attempt to eliminate evidence that could lead to their prosecution. Acid submersion is an increasingly popular method of body disposal due to its highly destructive effects upon organic tissues and their suitability for macroscopic analyses that could enable positive identification. Sixteen fleshed pig (Sus scrofa) forelimbs were submerged in hydrochloric acid, sulfuric acid, and sodium hydroxide (n = 2 per trial) under control conditions and heated to 40˚C or 100˚C, to determine whether dissolution of all tissues was possible quickly enough to ensure a practical method of disposal, and whether heating would accelerate this process. Hydrochloric acid (31-35%) under control conditions failed to dissolve all soft tissues, but destroyed all bones within 68 hours; at 40˚C the soft tissues still were not entirely dissolved, but all bones were destroyed within 24 hours. Sulfuric acid (93%) under control conditions destroyed all soft tissue within 52 hours and all bones within 28 days. Sulfuric acid at 40˚C destroyed all soft tissue in 2.75 hours and all bones within nine days; at 100˚C all soft tissues were destroyed within 0.75 hour and all bones within nine hours. Sodium hydroxide (20-30%) failed to dissolve the soft and hard tissues in all trials, but the rapidity of alterations observed was positively correlated to temperature. The present research indicates that these chemicals can destroy large, fleshed body parts and that this destruction can be accelerated through heating.

Blowflies (Diptera: Calliphoridae) are main colonizers of decomposing remains and any information on the influences of their lifecycle of growth and development are important to forensic entomologists when estimating postmortem interval during a medicolegal death investigation. Pupal survival of blowfly species, Lucilia sericata were studied at different developmental stages following pupation, white (0-12 hrs), young (24 hrs), medium (5 days), old (9 days) were submerged at various immersion intervals ranging from 1 hr to 120 hr (5 days) in different water types (fresh, salt, polluted, and drinking water). Control group (N= 100) were white pupae that were not submerged were also observed in order to compare the survival and eclosion rate. Two trials of the submergence process were conducted to observe the pupae survival. Data were analyzed using multiple logistic regressions in a 3-way interaction to determine if significant differences were seen between the water, time in water, and pupal stage. Dissolved inorganic nitrogen (DIN) of NH4+, NO2-, NO3-, and oP or DIP were analyzed to examine to determine if a correlation between the water types could be seen. DIN analyses exhibited similar NO2- + NO3- and NO3- in polluted and fresh water. The results show that as the pupae developmental age progressed, the pupae generally survived longer immersion intervals. The survival of white pupae decreased with the increase of submergence for all four water types, exhibiting a 100%mortality rate with pupae submerged longer than 24-36 hours. While pupae immersed in polluted water had similar survival rates in the white stage, the survival rate declined as the developmental age increased for pupae immersed in polluted water. Pupae immersed in salt and polluted water had earlier eclosion times when compared to other water groups, emerging at 36 hours from when the control group first emerged at day 12. Understanding the survival rate of submerged Lucilia sericata (Diperta: Calliphoridae) pupae will be potentially useful for criminal investigations by providing a better understanding of the survival of pupae submerged in different aquatic environments.

The positive identification of a decedent is paramount to a forensic investigation in which human remains have been recovered and must be identified. Due to increasing global mobility in the world's populations, it is not inconceivable that an individual might die far away from his or her home. Pinpointing an individual's geographic origin may contribute to definitive forensic identification of contemporary human skeletal remains in cases where dental records and other means of identification are either unavailable to law enforcement personnel or do not yield immediate results. Stable isotope analysis of biogenic tissues such as tooth enamel and bone mineral has become a well‐recognized and increasingly important method for determining the provenance of human remains, and it has been used successfully in bioarchaeological studies as well as forensic investigations. Both 18O and 2H stable isotope signatures are well established proxies as environmental indicators of climate (temperature) and source water and are therefore considered reliable indicators of geographic life trajectories of animals and humans. Similarly, 13C and 15N abundance data have distinguished dietary preferences in ancient human populations, and have been used to qualify 2H and 18O geolocational data that may be consistent with more than one location. Few if any studies have systematically investigated the multi-isotopic signatures in human tooth enamel and dentin from living individuals. Since 18O abundance values obtained from tooth enamel of late-erupting molars are a source of information on geographic origin of an individual during adolescence when crown formation takes place, it was hypothesized that: 1) the stable isotope abundance of 2H, 18O, and 13C in human tooth enamel and dentin is consistent with self-reported residential history and dietary preferences data, and 2) the isotopic variability evident between individuals with shared residential history and nutrient intake is quantifiable, and indicative of intra-individual variability. Two pilot studies were conducted to: 1) evaluate the feasibility of extracting and measuring the 2H composition of human tooth enamel and its suitability as a proxy for human geographic provenance, and 2) compare the isotopic abundance of isotopic abundance of 2H and 13C in human crown dentin collagen obtained from archaeological and modern teeth with the 18O and 13C isotopic composition of the corresponding tooth enamel carbonate. A protocol for preparing tooth enamel for 2H analysis was successfully devised and implemented; however, no correlation was observed between tooth enamel 2H abundance values as measured plotted against source water 2H abundance values. While unexpectedly low rates of hydrogen exchange within mineral hydroxyl groups were documented, and it was possible to analyze tooth enamel for its 2H isotopic composition, the seemingly fixed nature of 2H abundance in tooth enamel means that the 2H isotopic signature of tooth enamel cannot be used as an indicator of geographic provenance. Conversely, positive correlations between collagen 2H abundance values of primary dentin with 2H abundance values for source water and also with enamel 18O abundance values suggests that primary dentin collagen 2H values are linked to the isotopic composition of source water. Third molar tooth enamel was sampled from 10 living volunteers undergoing routine tooth extractions at University of Toronto affiliated dental clinics in Ontario, Canada. The mixed-sex group of patients was given questionnaires in which they provided detailed residential history and answered questions pertaining to dietary preferences (e.g., vegetarian) prior to donating all four third molars. Enamel was drilled from the crown of two third molars from each subject, chemically cleaned, and subjected to an acid digest before being analyzed for its 18O and 13C composition using Isotope Ratio Mass Spectrometry. Herewith, isotope abundance values are presented using the delta notation as delta values in per mil (‰). Mean d13CVPDB values for all samples ranged from -9.47 ‰ to -11.31 ‰ (pooled mean = -10.37 ‰), which suggested a persistent C4 plant dietary influence at the time the sampled tooth enamel was forming and is consistent with the typical North American diet. While inter-subject variation contributed the largest proportion of total d13C variability, differences were not significant. The pooled mean d18OVSMOW value for enamel samples was 24.39 ‰, while individual subject mean d18OVSMOW values ranged from 23.76 ‰ to 25.18 ‰. Marked offsets (0.01 ‰ - 0.51 ‰) in mean d18OVSMOW values for each pair of third molars were observed. While subject variation was significant (p=0.0034), neither diet nor sex significantly influenced the oxygen (or carbon) isotope data. Following conversion of d18OVSMOW values to d18OPhosphate values, drinking water values were calculated using the Daux et al. (2008) equation, and compared to their corresponding regional estimated annual average d18O values in precipitation retrieved from the Online Isotopes in Precipitation Calculator (OIPC) (Bowen 2014). Despite observed correlations between the drinking water d18OWater values and d18OOIPC values of four subjects, no statistically significant correlations were evident between the two limited data sets. However, when the isotopically similar d18O values of Toronto area residents were averaged and combined with the remaining Canadian data and the 18O data from 5 enamel samples analyzed in the 2H enamel pilot study, strong positive correlations were evident between d18OPhosphate valuesand d18OOIPC values (R2 = 0.87). Moreover, an equally strong linear relationship was observed between modeled annual precipitation 18O and calculated source water 18O (R2 = 0.87). Based on the d2H, d18O, and d13C values measured in tooth enamel and dentin, it is possible to infer and confirm geographic provenance and dietary intake. However, while enamel carbonate d13C values were consistent with self-reported dietary intake information and residential history, as could be expected vegetarians could not be distinguished from those who consumed meat without determining C/N isotopic ratios in dentin collagen. Further, the presence of strong linear relationships between the 18O composition of enamel carbonate and modeled source water 18O in the merged dataset illustrates the importance of considering site-specific isotopic complexities and using multi-isotope data obtained from multiple tissues when investigating the geographic origins of humans in an archaeological or forensic context. It is not possible to quantify intra-individual isotopic variability without sampling from larger, geographically diverse populations and controlling for as many variables as possible. The construction of regional databases containing 18O and 2H isotopic data obtained from a variety of environmental and human and faunal tissue samples, and the application of such data to individual cases in which geographic origins are desired, is recommended provided the following caveats are considered: 1) whenever possible, d18OPhosphate values should be used when comparing d18O values in tooth enamel with those in precipitation in order to avoid the unmitigated error associated with the application of carbonate conversion equations to enamel phosphate d18O data, 2) the continuous consumption of food sourced elsewhere is liable to affect the overall enamel carbonate d18O values, 3) d18O values in precipitation are not inclusive of the variety of postprecipitation and hydrological processes unique to a particular location, nor are they an accurate representation of the isotopically mixed nature of tap water sourced from distant reservoirs. Hence, extrapolations should be made with caution. Enamel sequential microsampling methods may be advisable for narrowing down a geographic timeline if the overlapping of isotopic signals at various points along the tooth’s longitudinal plane can be quantified and validated. While standardization of analytical methodology is critical to appropriate interpretations of the data, stable isotope profiling is not a standalone method and should be used in conjunction with other lines of evidence in determinations of human provenance.

xii, 57 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / The goals of this study are to assess a) the role of mass and velocity on the size of entrance wounds, b) the presence or absence and types of exit wounds, and c) the role of gender in choosing to commit suicide with a firearm. The results of an ANOVA revealed that the combination of a bullet’s mass and the relative velocity of the weapon is the most significant factor in entrance wound size. A logistic regression found that mass plays the most significant role in the presence of an exit wound. When considered separately, velocity had a more significant effect on exit type than did mass. The study also found that being male increases the odds that a firearm will be chosen to commit suicide. Handguns and the head were the most common choices for weapon and wound location, respectively, in both firearm suicides and homicides. / Committee in charge: Dr. John Lukacs, Chairperson; Dr. Andrew Karduna, Member; Dr. David Levin, Member