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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Examining distal humerus morphological variation in Thai individuals using elliptical Fourier analysis

Blanton, Amelia Irene 20 February 2021 (has links)
Sexual dimorphism of the distal humerus has been used for the development of morphometric sex estimation methods in human identification. In particular, visual assessment of the olecranon fossa, trochlear shape, and medial epicondyle angle are variably successful in differentiating females and males in African, Asian, and European groups. However, the influence of other factors on the distal humerus has yet to be fully explored. This study utilizes elliptical Fourier analysis (EFA) to examine the shape of these three features for evidence of sexual dimorphism and the effects of age-at-death, stature, and humeral measurements in 261 modern Thai individuals (f=116; m=145), 20-97 years of age. Left humeri were measured, photographed, traced, and analyzed in SHAPE v. 1.3 for EFA. Chi-square, ANOVA, and principal component results indicate sexual dimorphism in the olecranon fossa and trochlear extension shapes, both of which are correlated with epicondylar breadth. Trochlear extension was also found to be correlated with minimum midshaft diameter, vertical head diameter, and stature. The medial epicondyle was not correlated with any of the other factors examined, and age was not correlated with any of the shapes. High rates of intra- and interobserver error were found in the tracings of the three features. While future research should assess methods that better capture the medial epicondyle and improve reliability, features of the distal humerus are sexually dimorphic and somewhat affected by stature and/or body size.
22

Using SPME and GC-MS to detect nicotine from teeth as an indicator for tobacco use

Muschal, Alexis 10 March 2022 (has links)
In the United States, 19.3% of adults use some form of tobacco. Nicotine is a compound that is present in tobacco. Nicotine also has been detected in the calculus of teeth of archaeological specimens. The teeth are often well-preserved in unidentified human remains and are resilient in terms of damage from physical or chemical degradation. Dental plaque and calculus form on teeth and can entrap many chemical traces of compounds to which teeth are exposed. Many studies have examined the calculus microscopically and chemically using various techniques to establish patterns in diet, behavior, and health. Forensic odontologists can assist in the identification of individuals using dental records, but some individuals may not have recent or relevant records. In addition, some skeletal remains might only include a partial mandible or maxillae or may consist of only disarticulated teeth. However, given their representation in the anthropological record and the persistence of dental calculus on teeth postmortem, analyzing teeth for behavioral indicators can provide anthropologists with significant information to assist with identifying an individual. For example, detecting the presence of nicotine from teeth can provide information about tobacco use habits of an individual. In this study, the hypothesis was tested whether nicotine can be detected from teeth. It was also hypothesized that different behaviors of use would yield different quantities of nicotine in calculus, and that some nicotine in lower but detectable quantities may still be present from the teeth of non-users. Eighty-two teeth from the Boston University Goldman School of Dentistry were collected from tobacco users and non-users, which were determined by anonymous survey. All teeth were analyzed using gas chromatography mass spectrometry. Three types of sample extraction were tested. Solid-phase microextraction (SPME) was used with two subgroups of the overall sample. For Sample Groups A (n=41) and B (n=18), teeth were heated at 80ºC for an hour in a 20 mL SPME vial. An 85 μm polyacrylate SPME fiber was exposed to the headspace of the vials for 15 minutes for teeth in group A and 30 minutes for teeth in group B. For sample group C (n=24), teeth were sonicated in 5 mL ethanol for 30 minutes. After sonication, the ethanol was pipetted into autosampler GC vials. All samples were analyzed on an Agilent Technologies 7890A Gas Chromatography system connected to and Agilent Technologies 5975C inert XL EI/CI Mass Spectrometer and data produced were analyzed using Agilent ChemStation Software. Gas chromatography –mass spectrometry parameters were consistent across all samples, with a solvent delay for the group C samples. Results indicated that while SPME is sensitive enough to detect spiked nicotine from prepared samples, the extraction method did not show any significant data which would identify users. For the samples which were extracted by sonication in methanol, there was an increased likelihood that teeth belonging to a user had a positive identification for nicotine. Of the sonicated samples, 63.6% of teeth from tobacco users showed a positive hit after sonication, while none of the non-user teeth had positive nicotine hits. However, the amount of nicotine detected from each sample does not necessarily reflect tobacco user behavior such as daily frequency, years of use, or type of tobacco.
23

The genetic prehistory of the lower Illinois River valley| An ancient DNA analysis of Yokem Mounds 1-5

Millward, Georgia Grunewald 29 December 2015 (has links)
<p> Yokem Mounds and its neighboring lower Illinois River valley sites were part of a dramatic cultural shift that occurred during the transition from the Late Woodland period (A.D. 400-1050) to the Mississippian period (A.D. 1050-1400) of Illinois prehistory. Evident changes in diet, burial treatment, and material culture accompanied this transition at Yokem Mounds. What remains unknown is whether the transition co-occurred with a population displacement by originators of the Mississippian culture, the Cahokians, or other Mississippian immigrants. My ancient DNA analysis of Yokem Mounds 1-5 tackled this question, as well as described other cultural behaviors in order to identify additional impacts of the Mississippian culture. </p><p> I typed the mitochondrial DNA of 21 Late Woodland and 23 Mississippian individuals and placed the results within the context of previous genetic studies of the lower Illinois River valley and other ancient Midwest populations. I determined that there was genetic continuity between the Late Woodland and Mississippian populations, both populations practiced patrilocal postmarital residence patterns, and neither had burial patterns organized by matrilines. The differences in maize consumption as determined by stable isotopic signatures amongst the Late Woodland population were not associated with matrilineal familial diet preference. The population genetic analysis identified genetic connections between Yokem Mounds and contemporaneous populations at Schild Cemetery, Orendorf, and Angel Mounds; but Yokem Mounds was significantly different from the Oneota population at Norris Farms #36. Additionally, <i>Mycobacterium tuberculosis</i> Complex DNA was recovered from eleven individuals from Yokem Mounds and Schild Cemetery. Notably, two of these individuals date to the Middle Woodland period (100 B.C.-A.D. 400), which is the earliest identification of <i>Mycobacterium tuberculosis</i> complex DNA in the lower Illinois River valley. Overall, this research further expands our understanding of Native American prehistory and the demographic changes that occurred prior to European contact.</p>
24

A Metric Investigation of the Cranial Base and Vertebrae Among Extant African Homininae| Discrimination Across Posturo-Locomotory Complexes

Lukaszek, David Alexander 11 May 2017 (has links)
<p>Abstract Cranial base angle, vertebral dimensions, vertebral curvature, and locomotive behavior differ among Homo, Pan, and Gorilla; but many distinctions are obfuscated by dimensional and behavioral overlap among the genera and their fossil relatives. To address these issues, cranial and vertebral measurements (suites) were examined among Homo, Gorilla, and Pan as representative hominines for their posture and locomotion or positional-locomotory complexes. An additional analysis considered Australopithecus afarensis (A.L. 288-1 and A.L. 333) for comparative purposes. Using size-adjusted values with applied Bonferroni adjusted alpha levels, significant results for both the Kruskal-Wallis H-test and Mann-Whitney U-tests indicated statistically significant differences among species for cranial base angle (p = 0.000) and vertebral body dimensions with coronal and sagittal facet orientation (p = 0.000 ? 0.003). Detected significance was present for thoracic and lumbar curvature (p = 0.000) and positional-locomotory complex (p = 0.000) among species, albeit only cranial base angle was significant for the Pan-Gorilla comparison. Moreover, post hoc Spearman?s rho tests indicated significant results (p = 0.000 ? 0.009) with strong positive and negative correlations throughout the column for each species. However, no pattern among vertebral measurements throughout the vertebral column was detected. Lastly, Multinomial Logistic Regression yielded a correct classification percentage with significant model fit (p = 0.000) of 86.4% for the cranial base, 82.8-97.0% for all subsequent vertebrae, and 80.3% for thoracic and lumbar curvature among species. Positional locomotory complexes were also significant (p = 0.000) and yielded a correct classification percentage of 82.2% among bipeds and the two modes of knuckle-walking practiced by Pan and Gorilla respectively. However, misclassifications between human and nonhuman primates for cranial base angle and calculated vertebral curvature suggest that these variables are not viable for assessing either genera or positional-locomotory complexes. Lastly, both Australopithecus afarensis specimens (A.L. 288-1 and A.L. 333) were incorrectly classified. The A.L. 288-1 specimen identified as Homo and the misclassification of A.L. 333 as Pan suggest either species or vertebra misidentification. Overall, the data indicate that both vertebral corpus dimensions and coronal and sagittal facet orientations differ significantly among hominine taxa and can distinguish species and their respective posturo-locomotory complex. As for the evolutionary implications, human bipedalism is distinct as related to cranial base angle and vertebral measurements; however significant differences between Pan and Gorilla suggest homoplasy among measurements and denote parallelism for the emergence of knuckle-walking.
25

Age estimation using the sternal end of the clavicle: a test of the Falys and Prangle (2014) archaeological method for forensic application

Price, Meghan D. 09 March 2017 (has links)
Age estimation is a critical component of the biological profile in forensic and bioarchaeological contexts. The majority of age estimation methods are most accurate for individuals of younger age cohorts, typically those under 40 years of age. Skeletal degeneration can vary greatly between individuals, making age estimation less accurate for adult individuals. While there are some methods that attempt to age older individuals accurately and precisely, more research must be conducted to expand the range of methods available. Falys and Prangle (2014) developed a method for estimating age in individuals over the age of 40 using three degenerative characteristics of the sternal end of the clavicle: (1) surface topography, (2) porosity, and (3) osteophyte formation. In order to test their method, a sample of 1,510 individuals of known sex and age, ranging from 20 to 101 years of age (males: n = 1112, mean = 50.57, SD = 18.015; females: n = 398, mean = 53.065, SD = 20.358), were drawn from the McCormick Collection and the William M. Bass Donated Skeletal Collection at the University of Tennessee. Due to the paucity of remains of other ancestries, only individuals of reported White ancestry were used in this study. The two estimation methods proposed in Falys and Prangle (2014), regression equation and composite score, were tested to see how well they perform when applied to a different sample population than the populations used to develop the method. When applied to the collected data, the regression equation produced age estimations that fell within the 95% confidence interval in 47.6% of the male sample and 57.4% of the female sample. Composite scores were calculated and compared to the corresponding age ranges provided in Falys and Prangle (2014). The composite scores of the male sample estimated the age of an individual more accurately than the composite scores of the female sample (male = 65.9%; female = 58.8%). The lowest estimation accuracy for both males and females was between 70-79 years of age (male = 46.0%; female = 51.4%). From 80-89 years of age, the accuracy increased for males (76.4%) and females (69.4%). The sample also included individuals under the age of 40 in order to test whether the inclusion of clavicles with recent epiphyseal union would affect the applicability of the Falys and Prangle (2014) method. Multiple regression equations were generated: (1) individuals over 20 years of age, (2) individuals over 30 years of age, and (3) individuals over 40 years of age. The results from the multiple regression analyses show comparable Pearson’s coefficients for the above mentioned equations (r = 0.690, r = 0.632, and r = 0.611, respectively). Spearman’s rank correlation coefficients indicated a correlation significant at the 0.01 level for all three components individually, as well as the composite score. Of the three components, surface topography was most strongly correlated with age for both males (r = 0.643) and females (r = 0.590). Unlike the findings of Falys and Prangle (2014), porosity was found to be the least correlated with age for both males (r = 0.474) and females (r = 0.514). In addition, when broken down into ten year intervals (40-49, 50-59, etc.), the correlation coefficients increase with advancing age. This suggests that the method becomes more accurate as the age of an individual increases. The inter-observer and intra-observer agreement tests produced very low agreement values. The low observer agreement indicates that the current scoring method is not a reliable, repeatable technique. However, when examined further, the observed trait values that differed between the tests primarily differed by one score. These results suggest that condensing the scores in order to account for more variation would likely increase the observer agreement. However, condensing the scores would result in larger age intervals, which nullifies the purpose of this method. The findings in the present study indicate that the sternal end of the clavicle has potential for use in age estimation in older individuals. Although the present study produced lower correlation coefficients than proposed by the original study in 2014, the correlations and age-at-transition test results suggest that the sternal end of the clavicle deteriorates in a predictable manner that, with more observation and understanding, could be used to accurately age older individuals more precisely than the large age intervals currently in use. Despite the correlations between the degeneration of the sternal end of the clavicle and the age-at-death, the error rates suggest it is not a reliable alternative to the current methods used.
26

The height of the pubic tubercle as an indicator of parturition

Aurigemma, Tracy Ann 12 March 2016 (has links)
Parity status is a supplemental element of the biological profile in forensic anthropology. The pelvis is thought to exhibit alterations to the bone from pregnancy. Two features of the pelvis have been studied for signs of parturition or past pregnancy. The features have been studied with varying results. They include the pubic bone (Bergfelder and Herrmann, 1980, Cox and Scott, 1992) and the preauricular sulcus (Houghton, 1974, Dee, 1981). Maass and Friedling (2014) also looked at the interosseous groove and the iliac tuberosity. This study was modeled on Snodgrass and Galloway (2003) that investigated whether or not parity status can be determined by analyzing several areas of the pubic bone for different traits. Snodgrass and Galloway assessed the dorsal surface of the pubic bone for pitting and measured the height of the pubic tubercle. They also rearticulated the pelves of each subject and measured the arcuate angle. For the current study, a sample of 75 females from the William M. Bass Skeletal Collection at the University of Tennessee, Knoxville was examined. The height of the pubic tubercle and its distance from the symphyseal face was measured bilaterally for each individual. Also, the dorsal surface of each pubic bone was visually assessed for the presence or absence of pitting. Data analysis was then conducted comparing each of these features with parity status. BMI was also calculated for each individual and compared with the three features listed above. There were no correlations found between height of the pubic tubercle, distance of the pubic tubercle, dorsal pitting and parity status. The lack of a correlation between any of the features and parity status make them unusable in forensic applications.
27

Intrinsic Properties of Bone as Predictors of Differential Survivorship

Golda, Stephanie DuPont 15 April 2019 (has links)
<p> Investigating intrinsic properties as determinants of bone survival has major implications in forensic anthropology. It is useful in the incomplete recovery of a skeleton to know if certain bones that are missing are those that are expected to be missing. Assuming complete recovery, individual skeletal parts should have different recovery probabilities. This research examines the differential survivorship of human skeletal remains based on intrinsic properties (density, size, and shape) of bone. Fifty skeletons from the William M. Bass Forensic Skeletal Collection at the University of Tennessee-Knoxville were measured to determine bone length (cm) and shape (sphere, disc, rod, or blade) for twenty skeletal elements. Density measures (HUs) of skeletal parts were recorded for 11 skeletons from the Texas State University Donated Skeletal Collection. These intrinsic variables were then compared to recovery frequencies from a forensic sample of Arizona-Sonoran desert border crossers (n=380). This study found a correlation between bone length and frequency (r<sub>S</sub>= 0.46) and significant differences in the mean recovery frequencies for shapes (p &lt; 0.05). Though no correlation was found for skeletal part density and frequency (r<sub>S</sub>= -0.21), structurally dense midshafts of long bones are recovered with a greater frequency than their corresponding epiphyseal ends (p &lt; 0.001). Furthermore, structurally dense crania have the highest survivorship potential (89%). This study substantiates differences in mean recovery frequencies for skeletal elements according to anatomical location (p &lt; 0.05). Anatomical regions and recovery frequencies were used to produce a simple taphonomic model. Educating law enforcement on the value and appearance of high survivorship bones in the taphonomic model is a recommendation to improve policy and practice.</p><p>
28

Assessing ancestry through nonmetric traits of the skull : a test of education and experience /

Wheat, Amber. January 1900 (has links)
Thesis (M.A.)--Texas State University--San Marcos, 2009. / Vita. Includes bibliographical references (leaves 46-49). Also available on microfilm.
29

Forensic anthropology : its contribution to forensic cases submitted to the University of Montana for analysis /

Byrne, Ana M. January 2006 (has links)
Thesis (M.A.)--University of Montana, 2006. / Mode of access: Internet. Title from title screen. Description based on contents viewed Oct. 26, 2006. Includes bibliographical references (leaves 37-40). Also available in print format.
30

The physical characterisation and composition of archaeological dental calculus

Cooper, Kayleigh Anne January 2017 (has links)
Dental calculus is a complex biological material that has been found to provide significant evidence of past population diet, health and habitual activity. It is composed of mineral phases, trace elements, organic species and can have inclusions such as starch granules and microfossils incorporated into its structure. This composition has been found to vary among individuals, although the reasons for this are poorly understood. Despite this, there is a wealth of knowledge that can be gained from analysing this biomineral, especially from archaeological remains. In past populations, the variables that affect composition, such as pharmaceuticals and diet are reduced compared to modern populations. As such the reliance on clinical studies that have investigated dental calculus from modern individuals, may be flawed when considering past populations. The focus of this study was to provide insight about the variation in physical characterisation and composition of archaeological dental calculus. Despite there being an abundance of archaeological dental calculus research, this is the first large scale compositional study of specimens from three separate past populations. In addition, this research is the first study to adopt a non-destructive to destructive approach to archaeological dental calculus analysis. As well, it is the first application of nanocomputed tomography to dental calculus from past populations. Consequently, this study demonstrates the first evidence of accumulation layering that has been detected using non- estructive nano-computed tomography. Furthermore, this research has identified three types of layering in archaeological dental calculus. Due to these findings, it is expected that this research will impact the future of dental calculus analysis, especially when considering dental calculus as a method of mapping an individual’s health, diet or lifestyle in the weeks or months prior to death. The overall results of this thesis demonstrate that some aspects of the morphological, mineralogical and elemental analysis of archaeological dental calculus are inconsistent with clinical literature. The results have also shown that there are some differences between the dental calculus from different archaeological populations which can be related to post-mortem burial conditions.

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