SEM-EDX Analysis of Gunshot Residue on Pig Cranial Bone Following Decomposition and Maceration

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Description
Distinguishing between projectile and blunt force or sharp force trauma can be complicated by processes that result in fragmentation or loss of skeletal features. Postmortem processes that obscure skeletal features may result in the inability to properly determine the mechanism

Distinguishing between projectile and blunt force or sharp force trauma can be complicated by processes that result in fragmentation or loss of skeletal features. Postmortem processes that obscure skeletal features may result in the inability to properly determine the mechanism of trauma using morphology alone. The presence of gunshot residue (GSR) is indicative of a gunshot event and can be used to differentiate between etiologies of skeletal trauma. Primer GSR is composed of barium (Ba), antimony (Sb), and lead (Pb), which are vaporized during the firearm discharge and can be deposited in small quantities on surfaces within proximity of a gunshot event. Scanning Electron Microscopes with Energy Dispersive X-Ray Spectroscopy (SEM-EDX) have been used in the past to detect GSR on a variety of surfaces including bone. The purpose of this study is to determine the ability to detect GSR on bone tissue using SEM-EDX following warm-water maceration or decomposition.
Date Created
2019-05
Agent

Analysis of Sexual Dimorphism in Sub-adult Crania

Description
Forensic anthropologists rely on the validated sex determination methods that utilize post-cranial elements in adult remains, but, recently, research has been conducted to determine adult remain sex using just the skull. Similar research for sub-adult remains is lacking the robustness

Forensic anthropologists rely on the validated sex determination methods that utilize post-cranial elements in adult remains, but, recently, research has been conducted to determine adult remain sex using just the skull. Similar research for sub-adult remains is lacking the robustness and validation that adult determination methods possess. This study utilized 20 crania measurements taken from CT scans of child patients with known sexes at the Phoenix Children’s Hospital to investigate if a sex determination method could be produced. The measurements were assessed with a t-Test, Linear Discriminant Analysis, and Principle Component Analysis to determine if sexual dimorphism was detectable and if the predictive model had discriminant power when the sample size was categorized by age. The results revealed that a few measurements were dimorphic, but were not statistically significant to determine the sex of a sub-adult outside of the sample population. Future investigations will remove age group classification to observe if this model can predict age.
Date Created
2019-05
Agent

Facial Growth in Aging Adolescents: The Implications on Pediatric Craniofacial Surgery

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Description
This study examines the utility of diagnostic CT scans as sources of data to quantify facial growth in children. Subadults often suffer facial trauma arising from a variety of circumstances. Pediatric surgeons are then confronted with devising surgical pre- and

This study examines the utility of diagnostic CT scans as sources of data to quantify facial growth in children. Subadults often suffer facial trauma arising from a variety of circumstances. Pediatric surgeons are then confronted with devising surgical pre- and post-operative strategies that present numerous complications. One of these involves predicting how specific areas of a child's face will change with time. The proliferation of CT scans use in pre-operative planning throughout healthcare provides potential data for addressing many concerns, including those involving facial growth. To add to the burgeoning body of literature focusing on facial growth and provide insight anatomical variation this study used data derived from CT scans from Phoenix Children's Hospital. Quantitative data derived from CTs were used to examine normative growth and develop predictive equations that surgeons can use to visualize facial change for males and female patients.
Date Created
2018-12
Agent

Distinguishing Post Mortem Faunal Predation from Intentional Sharp Force Trauma

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Description
Due to the nature of animals, even domesticated pets, animal scavenging of human remains is an important taphonomic factor. This area of study has, however, been undercounted in the current literature. The purpose of this study was to begin the

Due to the nature of animals, even domesticated pets, animal scavenging of human remains is an important taphonomic factor. This area of study has, however, been undercounted in the current literature. The purpose of this study was to begin the first step in creating a taphonomic profile for urban / household animal scavenging as distinguishable from manmade tool marks. Using volunteered animals and regularly available tools, alterations were made on beef ribs in order to characterize the distinguishing profiles between the two groups. It was found that animal scavenging alterations, in the short term (20 minutes used in this study) have a distinctly different appearance than tool mark alterations. Animal scavenging has less visible alterations, consistent bite morphology across different species, and symmetrical cut marks along the midsection of the long bones. Ultimately, this study was a successful first step in furthering taphonomic alteration database research across various biomes and conditions.
Date Created
2018-05
Agent

Ancestry Estimation in Forensic Anthropology: Osteological vs. Molecular Methods and Social Implications

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Description
Ancestry estimation in forensic anthropology has been one of the most complex determinations to make from the human skeleton. There is a long history in biological anthropology using different morphological characteristics from the skull and other areas of the skeleton

Ancestry estimation in forensic anthropology has been one of the most complex determinations to make from the human skeleton. There is a long history in biological anthropology using different morphological characteristics from the skull and other areas of the skeleton but it remains a difficult estimation that always has some variability. Currently, more studies have been conducted in morphological and metric methods from the skull of ancestry estimation to better the accuracy of the determination. Since most forensic cases are not in the best condition, there also must be other estimation methods from other bones from the remains such as the cervical vertebrae and the femur. These methods have some degree of accuracy but are not as commonly used in forensic cases as the skull is. It seems that the best method for ancestry estimation is to use a combination of multiple methods, having multiple lines of evidence. With the advent of DNA, many researchers have started to study the use of DNA in ancestry estimation. Genetics can be used in ancestry estimation as certain populations have allele frequencies that can be quantified. Using ancestry informative markers (AIMS), DNA can be used to estimate the ancestry of an individual as well as the amount of admixture in the individual. Many different methods have been tested in genetic evaluation of ancestry and have been supported with good accuracy. However, DNA analysis is expensive and time consuming, putting more reliance on osteological methods. Social implications have had a tremendous impact on the fate of ancestry estimation in forensic anthropology. Anthropology has generally rejected the notion of races but it is still used in forensics due to how much it is inculcated into everyday society. Also, the overarching theme of admixture is becoming more prevalent in society. This causes the estimations in forensic anthropology to be extremely difficult. If more research into ancestry estimation does not continue, the determination will almost be impossible to be made.
Date Created
2016-12
Agent

Unification and Reorganization of the United States Medical Examiner and Coroner Systems

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Description
In 2009 the National Academy of Sciences issued a publication outlining current issues in forensic science as well as key recommendations to fix relevant problems in fields ranging from comparative forensics to the death investigation system itself. These relevant problems

In 2009 the National Academy of Sciences issued a publication outlining current issues in forensic science as well as key recommendations to fix relevant problems in fields ranging from comparative forensics to the death investigation system itself. These relevant problems stem partially from a lack of a unification amongst nationwide standards and practices. A lack of resources, funding, and qualified personnel has halted any real change in death investigation.1 Rather than allow the disparate, varied, and sometimes less qualified role of the Coroner to persist in tandem with a Medical Examiner System, it is recommended that the United States suspend the Coroner System in its entirety to allow for a nationwide Medical Examiner System as the new sole standard in death investigation. This transition is both necessary and feasible. Presently, there are a number of challenges facing the proposed unification of the medicolegal death investigation field to include funding; addressing medical school needs; facilities in both rural and populated communities; and overarching legislative issues connected to such a large endeavor. This recommendation proposes solutions to establish a unified Medical Examiner System. This proposal is based on the state of New Mexico's death investigation system and thus can integrate forensic pathology into the medical education while utilizing the knowledge of practicing forensic pathologists where Medical Examiner Systems can fuse with medical schools. Milestones will be achieved in stages over a 15 year time frame as the United States makes the transition to a unified centralized Medical Examiner System.
Date Created
2017-05