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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.
31

Estudo do dimorfismo sexual por meio de medidas cranianas / Study of sexual dimorphism through skull measurements

Oliveira, Osvaldo Fortes de 07 February 2010 (has links)
Orientador: Eduardo Daruge Junior / Dissertação (mestrado) - Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-16T05:25:40Z (GMT). No. of bitstreams: 1 Oliveira_OsvaldoFortesde_M.pdf: 1686263 bytes, checksum: 011e66d64852b8a5da91c8f32159b2ce (MD5) Previous issue date: 2010 / Resumo: Objetivo: Verificar se há presença de dimorfismo sexual para cada uma das medidas realizadas no crânio e observar qual das medidas são mais confiáveis para elaboração de um modelo matemático que possa ser aplicado na prática forense. Material e métodos: A amostra foi composta de 100 crânios humanos, sendo 50 de indivíduos do sexo masculino e 50 do sexo feminino, com idade no momento do óbito superior a 22 anos, procedentes do cemitério São Gonçalo, da prefeitura municipal de Cuiabá - Mato Grosso/Brasil. Foram realizadas medições com paquímetro digital e compasso de ponta curva entre as seguintes estruturas anatômicas do crânio: násio-lâmbda; násio-básio; glabela-lâmbda; glabela-ínio; glabela-bregma; básio-lâmbda; básio-bregma; zígio-zígio; eurio-eurio; mastóide-mastóide. Para verificar o erro sistemático intra-examinador foi utilizado o teste "t" pareado e para determinação do erro casual foi utilizado o cálculo de erro proposto por Dalhberg. Foi utilizado o teste t Student para comparar se existe diferença estatisticamente significante nas medidas entre os sexos. Foi utilizada a análise discriminante modelo stepwise para verificar qual das medidas realizadas é mais relevante para ser utilizada em um modelo matemático para diferenciar o sexo. Resultado: O valor médio das medidas realizadas foi sempre superior para o sexo masculino em relação ao sexo feminino, sendo que a distância eurio-eurio foi a única entre as medidas que apresentou-se sem significância após aplicação da estatística com teste t de Student. Conclusão: A distância zígio-zígio foi a que apresentou maior dimorfismo entre os sexos, onde foi possível a obtenção de uma função por análise discriminante juntamente com a distância básio-lâmbda com confiabilidade de 72% de acerto. / Abstract: Aim: To verify the presence of sexual dimorphism for each of the measurements made in the skull and see which of measures are more reliable for developing a mathematical model that can be used in forensic practice. Material and methods: The sample consisted of 100 human skulls of 50 individuals were male and 50 female subjects, age at death of more than 22 years, coming from the cemetery São Gonçalo, the municipal government of Cuiabá - Mato Grosso / Brazil . Measurements were taken with a digital caliper and caliper pliers of the following anatomical structures of the skull: Násio-lâmbda; násio-básio; glabela-lâmbda; glabela-ínio; glabela-bregma; básio-lâmbda; básio-bregma; zígio-zígio; eurio-eurio; mastóide-mastóide.To check the systematic error intrarater test was used to "t" test and to determine the random error was used to calculate error proposed by Dalhberg. It was used the Student t test to compare if exist a statistically significant difference in measures between the sexes. It was used the stepwise discriminant analysis model to verify which of the measures taken are more relevant to be used in mathematical model to differentiate the sex. Results: The average value of measurements was always higher for males compared to females, and the distance eurio-eurio was unique among the measures that showed no statistical significance after applying with the Student t test. Conclusion: The distance zigio-zigio showed the greatest dimorphism between the sexes, where it was / Mestrado / Odontologia Legal e Deontologia / Mestre em Biologia Buco-Dental
32

Genome-wide analysis for native thyroid hormone targets in developing brain and mechanisms of endocrine disruption at the thyroid hormone receptor

You, Seo-Hee 01 January 2007 (has links)
Thyroid hormone (TH) plays an important role in fetal brain development. Therefore, exogenous factors that interfere with TH signaling may exert potentially important adverse effects on brain development. However the specific roles of TH in brain development are poorly understood. The goal of this research is to delineate the mechanisms of TH and potential mechanisms of endocrine disruption at the TH receptor in the developing brain. The dissertation showed that PCBs can reduce the circulating levels of TH, but simultaneously exerted TH-like effects on TH-responsive genes in fetal brain. To determine whether a specific PCB metabolite, 4-OH-PCB106, could exert a direct agonistic effect on the TRβ1, we employed chromatin immunoprecipitation (ChIP). These studies demonstrate that 4-OH-PCB106 acts as an agonist in GH3 cells, and does not alter the ability of TRβ1 to physically interact with the TRE in the growth hormone (GH) promoter, or with SRC1/NCoR. Interestingly, 4-OH-PCB106 appears to exert actions on gene expression in GH3 cells predominantly through TR, as evidenced by a focused study using differential mRNA display in GH3 cells. A significant impediment in identifying the ability of PCBs to interact with TRs in vivo is that few direct gene targets of TH are known. Therefore, we employed ChIP-on-chip in combination with whole transcriptome expression analysis. We identified 526 direct TH gene targets and these revealed major signaling networks regulated by maternal TH during fetal brain development, including cell-fate specification, cell migration and synaptogenesis. This combination of approaches provides a new look at the role of TH in fetal brain development. In a summary, despite the great deal of research focused on the mechanism of TH action, we do not have comprehensive understanding of the role of TH and its modulators in the brain. Therefore it is important to identify genes that may be direct targets of TH action. This is the first large in vivo database for native TREs in the fetal brain before the onset of fetal thyroid function. Therefore the result will provide profound impact in study of mechanisms of TH as well as endocrine disruptors at the TR in developing brain.
33

Detection of saliva on combustible and electronic cigarettes using the SERATEC Amylase Test and subsequent DNA analysis

Zhang, Kangning 09 November 2019 (has links)
Saliva can be detected on items including cigarette butts, glassware, clothing, human skin and condoms, and the identification of saliva on these types of evidence may be important to provide linkages or investigative leads in forensic cases. Sometimes when the presence of saliva is indicated, the item will be sent for deoxyribonucleic acid (DNA) analysis and may be used for identification of individuals involved in a crime. The detection of saliva mostly depends on the activity and the presence of amylase. The SERATEC® Amylase Test (SERATEC GmbH, Goettingen, Germany) is a lateral flow immunochromatographic test that targets the presence of human α-Amylase using two monoclonal anti-human-α-Amylase antibodies. This study investigates the effectiveness of using the SERATEC® Amylase Test to detect amylase on cigarette butts and vaping devices. In addition, the possible correlation between the SERATEC® Amylase Test result and the amount of DNA extracted from cigarette butt samples is evaluated. Results indicated that the cigarettes and vaping devices tested had no inhibitory effect on the SERATEC® Amylase Test. The SERATEC® Amylase test was able to detect amylase from various brands of cigarettes, marijuana cigarettes, JUULpods™ (JUUL Labs™ Inc., San Francisco, CA) and an additional vaping device. Negative amylase test results (22 of 114 samples) may be attributable to personal smoking habits and the texture of the cigarette butt wrap paper or vaping device. DNA quantification results indicated that the majority of cellular material was retained on the wrap paper even after submersion in the SERATEC® Amylase Test buffer. It is recommended that the wrap paper from the cigarette filter and the remaining extract from preliminary testing be combined prior to DNA extraction in order to maximize total DNA recovered from a cigarette sample. The correlation between the SERATEC® Amylase Test result and the quantity of DNA extracted from the same source was not linear. The presence of saliva and DNA concentration are controlled by different factors, thus using the detection of saliva to predict the recoverability of DNA on cigarettes may be valuable in some situations, but is not precise.
34

Fractography of fresh vs. dry bones

Satish, Reshma 27 February 2021 (has links)
Limited experimentation has been conducted on fractography of fresh versus dry bones. The present project examined the presence of select fractographic features on wet and dry bone specimens over a time interval of 15 months. The experimental remains consisted of a total of 81 white-tailed deer (Odocoileus virginianus) long bones as a proxy for human long bones. A subsample of 15 long bones that were defleshed of most external soft tissue was subjected to blunt force trauma every 30 days for a total of three months. After these three months passed, a subsample of 15 bones was subjected to blunt force trauma every 90 days for the remaining 12 months. Following fracturing, the long bones were macerated and the fractures on the long bones were inspected, and observations were recorded and photographed. The author hypothesized that the presence (or absence) of fractographic features including hackle patterns, bone mirror, cantilever curls, and arrest ridges, on the fractured long bones would differ on fresh versus dry bones. Therefore, the difference in fractographic features found on the fresh versus dry bones would allow greater separation of perimortem from postmortem fractures. Other fracture characteristics such as fracture angle, fracture surface texture, fracture jaggedness, number of fragments produced, and type of fracture produced were also observed as part of the data collected in this research to potentially confirm the findings and results of previous studies conducted on differentiating between perimortem and postmortem trauma on bone. This study disproved the hypothesis by concluding that the presence (or absence) of fractographic features is not greatly affected by time exposure and therefore, does not aid in distinguishing between fresh bone and dry bone fractures. Fractographic features were present and absent on bone specimens during all postmortem intervals. The only statistically significant difference discovered was that bone hackle patterns are more commonly observed than cantilever curls on bones with a later PMI. Other general trends observed were that the number of bones showing bone hackle patterns increased over time and the number of bones showing bone mirror decreased over time. In addition, the results of the study revealed that the only fracture characteristic that showed a slightly significant difference with time of exposure was the fracture surface texture produced. The probability of a bone showing intermediate fracture surfaces is statistically significantly higher than a bone showing rough fracture surfaces when the represented PMI is fresh. The probability of a bone showing intermediate fracture surfaces is statistically significantly higher than a bone showing smooth fracture surfaces when the represented PMI is dry. The present study showed that the fracture characteristics including fracture angle, fracture type, number of fragments produced, and fracture jaggedness were not greatly influenced by exposure of time but, certain patterns and trends were recognized. The number of bones showing sharp fracture angles increased over time, while the number of bones showing intermediate fracture angles stayed stagnant. Bones showing comminuted fractures also increased with the progression of drying time. The average number of fragments produced were high during both fresh and dry PMIs and low throughout the transitional postmortem intervals. Bones showing jagged, intermediate, and not jagged broken ends increased with the progression of time however, not jagged broken ends only began to appear in the sample starting at a PMI of 90 days.
35

A Multidisciplinary Approach to Skeletal Trauma Research: Interdisciplinary Methods and Applications

Harden, Angela Lynn 01 September 2022 (has links)
No description available.
36

The effects of child abuse : a skeletal and soft tissue analysis

Reay, Heather 01 January 2002 (has links)
The maltreatment of children has been recorded in history as early as the first century B.C. when weak and infirm children of the Ceylonese were reported to tarnish the rest of the healthy population and were put to death. The medical implications of child maltreatment however, have been recognized for less than a century. Pioneered by John Caffey in 1946, the advances in medical science technology and the education of the medical community have served as an infallible ally against abuse. Early studies reported a direct correlation between infants with reported subdural hematomas also having unreported long bone fractures. These undeniable correlations lead to a trend in the investigations on the mechanisms of non-accidental injuries and their manifested outcomes. Certain injuries when unsupported by appropriate history, or the presence of multiple injuries in different stages of healing, warrant specific investigations and should raise suspicion of abuse. In addition to clinical and medical evaluation, a physical evaluation of height and weight may indicate overall health. This thesis will research, through a literature review of published sources and exploratory data analysis, the effects of child maltreatment on the juvenile skeleton.
37

Identification of shark species based on tooth striation patterns made on bone

Gill, Rebecca M. 26 February 2024 (has links)
Shark attacks on humans are increasing every year, and due to this fact, it is important to understand the damage that these predators can inflict on bone. The present study examined the striation patterns that shark teeth leave behind on bones during an attack or scavenging event and determined whether they can be used to identify the species of shark involved. The present study examined twelve different species of sharks including white shark (Carcharodon carcharias), tiger shark (Galeocerdo cuvier), and bull shark (Carcharhinus leucas), as there are high incidences of attacks reported of these species. Striations were made in dental wax using the teeth of these species, as well as nine others including blue shark (Prionace glauca), tawny nurse shark (Nebrius ferrugineus), blacktip reef shark (Carcharhinus melanopterus), dusky shark (Carcharhinus obscurus), java shark (Carcharhinus amboinensis), gray reef shark (Carcharhinus amblyrhynchos), sand tiger shark (Carcharias taurus), cookiecutter shark (Isistius brasiliensis), and lemon shark (Negaprion brevirostris), to compare morphologies, their serration patterns, and what striations would be left on bone. It was hypothesized that the striations left in the impressions would be distinct to each species and would provide another method to identify species implicated in attack and scavenging events on humans. The results of this study suggest a statistically significant difference between the patterns of serrations found between some species of sharks examined. The white shark and the tiger shark can be distinguished from the other species in the present study. Further research on this method should be conducted, so future scientists can identify species involved in predation events and scavenging using striation patterns.
38

Correlation between chainsaw type and tool marks in sectioned bone

Moore, Gregory 22 January 2016 (has links)
This research determined if the patterns resulting from different chainsaw chain types impacting bone leave tool marks are dissimilar enough from one another to determine which type of chainsaw was used in dismemberment mimicking homicide cases. Multiple styles of commercially available chainsaw chains were used. The long bones of adult white tailed deer (Odocoileus virginianus) were cut to produce false start cuts and complete sectioning to mimic typical human dismemberment. The cut areas were examined macroscopically and microscopically to note features common to each chain. The chains were compared to one another to note differences. It was proposed that each chainsaw would leave different tool marks. It was found that the style of tooth significantly affects the size of the exit chipping, size of the breakaway notch, angling of the kerf floor, and the mass of bone wastage produced. The most significant differences were produced with a standard tooth. The skip of the chainsaw did not create significant differences. This research has applications in forensic anthropology through the additional information on tool marks and the ability to identify specific tool types. The information is also useful to law enforcement investigations involving dismemberments.
39

Improving semen identification and quantitation using protein mass spectrometry

Niles, Sydney 17 June 2019 (has links)
Studies have highlighted a growing national problem regarding the number of untested Sexual Assault Kits (SAKs). A 2011 National Institute of Justice report revealed Los Angeles alone had 10,000 untested SAKs. This backlog has fueled the need for specific and efficient testing of SAK evidence. In traditional workflows, serology tests are used to indicate the presence of a targeted bodily fluid and prioritize samples for genetic analysis. However, given the lack of sensitivity and specificity of modern serological assays, current SAK workflows often skip serological identification altogether for a “direct to DNA” approach. While these Y-Screen workflows achieve rapid screening of samples for the presence of a detectible male contributor, they do not provide any serological information. As a result, samples lack what can be critical investigative context. Improved serological capabilities with enhanced sensitivity and specificity would provide greater confidence in results for the confirmatory identification of seminal fluid. At a minimum, forensic biologists should understand the limitations associated with traditional serological approaches to seminal fluid identification when processing SAK samples. Current serological techniques based on antigen-antibody binding have exhibited both sensitivity and specificity limitations. False positive results for semen can be obtained by non-target biological fluids such as breast milk, urine, and vaginal fluid, or by non-specific binding events. This study evaluates a promising emerging technique that combines high specificity protein biomarker detection with targeted mass spectrometry. This research targeted human-specific peptide markers for seminal fluid proteins and peptide standards to perform quantification of seminal fluid peptide targets using an Agilent 6495 mass spectrometer coupled to a 1290 series liquid chromatograph. This approach has shown to be both more specific and sensitive in identifying a bodily fluid compared to current immunological based approaches. Thus, this proteomic workflow was used to evaluate authentic false positive rates of current immunochromatographic techniques for seminal fluid identification. Self-collected vaginal swabs collected from participants not engaging in barrier-free vaginal intercourse with male partners were tested using various immunochromatographic assays designed to detect both semenogelin (Sg) (RSID™-Semen) and prostate specific antigen (PSA) (ABAcard® p30 Test and SERATEC® PSA Semiquant). Similarly, three seminal fluid biomarkers (semenogelin 1, semenogelin 2, and prostate specific antigen) were used for seminal fluid identification via mass spectrometry. Any samples producing positive results on any immunochromatographic assay were evaluated to determine whether the target protein was actually present at levels above the reported sensitivity limits of the lateral flow tests. Additionally, Sperm HY-LITER™ Express was used to microscopically confirm the absence of spermatozoa in all samples producing positive immunochromatographic results. In addition to using the quantitative proteomic assay to estimate the rate of authentic false positive results associated with lateral flow assays, this research sought to establish the correlation (or lack thereof) between absolute quantitation of seminal fluid markers and the ability to successfully generate DNA profiles. Self-collected post-coital swabs from donors engaging in barrier free vaginal intercourse with male partners over varied periods of time between 1-8 days after intercourse were collected. All samples were analyzed using the quantitative seminal fluid protein mass spectrometry assay, once again targeting SgI, SgII, and PSA. Both autosomal STR profiles (GlobalFiler™) and Y-STR profiles (Yfiler™ Plus) were subsequently generated. With regard to immunochromatographic assay false positive rates, a total of 17 false positives for semen were observed (n=150), 14 of which were consistent with PSA and 3 with Sg, for a corresponding total false positive rate of 9.3% and 2%, respectively (11.3% overall). These samples were all confirmed to be sperm negative with mass spectrometry and microscopic analysis. This data supports the use of current immunochromatographic assays for the presumptive detection of seminal fluid while also providing further support for the improved specificity of alternative serological approaches using mass spectrometry identification of biological targets. With regard to the relationship between quantitative levels of target seminal fluid peptides and the ability to generate STR profiles from vaginal swabs collected at various post coital intervals, a total of 61 post-coital samples were tested. Of these, 48 samples had a seminal fluid target greater than the limit of quantitation for the mass spectrometry assay and 26 produced an STR (n=9) and/or Y-STR (n=10) profile. A correlation between peptide quantitation and ability to generate a genetic profile was unable to be determined from this initial sample set. Overall, however, it has been demonstrated that the use of proteomic mass spectrometry for the identification of seminal fluid targets (with its enhanced sensitivity and specificity) would enable forensic practitioners to make better use of serological information during the analysis of challenging sexual assault samples.
40

Computational Methods for Age-at-Death Estimation Based on the Pubic Symphysis

Unknown Date (has links)
The identification of forensic cases often includes the use of skeletal elements to assess the age-at-death of an individual. The pubic symphysis is the preferred and most often used skeletal age indicator. Standard techniques, such as the Suchey-Brooks system, require that the morphology of the pubic symphysis is visually compared to shape characteristics typical for phases with associated age intervals. As individual factors accumulate during the aging process, estimating the age-at-death for older individuals becomes increasingly more difficult. In addition, methods based on visual inspection of the bones introduce some level of subjectivity and observer-related error. This research makes use of about 100 3D laser scans of the pubic symphysis of white male skeletons with known ages-at-death, and proposes several objective, quantitative methods for shape analysis that aim to provide a surface or outline measure of the shape of the scans that minimizes the age-estimation error. The proposed methods include the use of thin plate splines, two-dimensional Fourier, wavelet and elliptic Fourier analysis, and a technique that uses the radius of a best fitting circle (in 2D) or sphere (in 3D) as a measure of the curvature of a shape. In addition some refinement and partitioning techniques were implemented. The project investigates the relationship between the exact age-at-death and the different measures produced by each method. Also included are results of applying a recently proposed computational method, the SAH-Score, to new scan data and scan partitions. As a final result, the project proposes multivariate regression models that combine the measures with highest statistical significance to minimize the age estimation error (about 12 years) and maximize the adjusted R-squared value (over 55%). Furthermore, the results are subjected to two cross-validation analysis to test for the accuracy of the models when used in practice. / A Dissertation submitted to the Department of Scientific Computing in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester 2015. / November 3, 2015. / Includes bibliographical references. / Dennis Slice, Professor Directing Dissertation; Michael Creswell, University Representative; Bridget Algee-Hewitt, Committee Member; Peter Beerli, Committee Member; Xiaoqiang Wang, Committee Member.

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