Matching Items (9)
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- All Subjects: Forensics
- Creators: School of Mathematical and Natural Sciences
- Member of: Theses and Dissertations
Description
Bloodstain pattern analysis can provide telling evidence from a crime scene based on the clues left in the blood, but the field itself is highly problematic since the evidence extracted is dependent upon the interpretation of the analyst. Although some aspects of this type of analysis have been scientifically supported, most are not seen as positively accurate. Since certainty is the basis for acceptance of courtroom testimony, it is important that these unsettled aspects become more understood. This experiment examines the diameter of a weapon and how it affects its cast-off pattern. Weapons with four different diameters were used to generate 5 sample patterns under controlled conditions from each weapon diameter for a total of 20 patterns consisting of 3,367 droplets. The length and width of the pattern, the total number of droplets in the pattern, and the percentage of each droplet type (classified into low-velocity, medium-velocity, and high-velocity droplets) were recorded, averaged, and compared to each other individually using a t-test difference of two means assuming unequal variances. The results reveal that a higher percentage of droplets greater than 4 mm may indicate the use of a weapon with a wider diameter. The data also shows differences between the weapons that may be related to other factors besides the diameter of the weapon such as surface area or the curvature of the weapon. Still, more testing must be conducted to support these theories.
ContributorsBetz, Alexandra Marie (Author) / Kobojek, Kimberly (Thesis director) / Jacobson, David (Committee member) / School of Humanities, Arts, and Cultural Studies (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Women and people of color are some of the most underrepresented groups in the STEM field (science, technology, engineering, and mathematics). The purpose of this study was to uncover the barriers that undergraduate Hispanic women, as well as other women of color, face while pursuing an education in a STEM-related major at Arizona State University (ASU). In-depth interviews were conducted with 13 adult participants to dig deeper into the experiences of each woman and analyze how race and class overlap in each of the women's experiences. The concept of intersectionality was used to highlight various barriers such as perceptions of working versus middle-class students, the experience of being a first-generation college student, diversity campus-wide and in the classroom, effects of stereotyping, and impacts of mentorships. All women, no matter their gender, race, or socioeconomic status, faced struggles with stereotyping, marginalization, and isolation. Women in STEM majors at ASU performed better when provided with positive mentorships and grew aspirations to become a professional in the STEM field when encouraged and guided by someone who helped them build their scientific identities. Working-class women suffered from severe stress related to finances, family support, employment, and stereotyping. Reforming the culture of STEM fields in higher education will allow women to achieve success, further build their scientific identities, and increase the rate of women graduating with STEM degrees.
ContributorsValdivia, Lilianna Alina (Author) / Kim, Linda (Thesis director) / Camacho, Erika (Committee member) / School of Mathematical and Natural Sciences (Contributor) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Abstract Latent fingerprints are a critical component of the evidence that is captured and analyzed from crime scenes and presented for convictions in court. Although fingerprint science has been used for many years in forensics, it is not without many criticisms and critiques from those that believe it is too subjective. Researchers from many disciplines have tried to refute this claim by completing experiments that would eventually lead to a fingerprint aging technique as well as providing statistical models and mathematical support. In this literature review, the research that has been widely published and talked about in this field was reviewed and analyzed to determine what aspects of the experiments are benefitting the study of degradation. By carefully combing through the methods and results of each study, it can be determined where future focuses should be and what disciplines need to be exploited for knowledge. Lastly, an important aspect of the experiments in recent years have depended on the collaboration with statistics so this evidence was examined to identify what models are realistic in determining error rates and likelihood ratios to support latent fingerprint evidence in court. After a thorough review, it is seen that although large strides have been taken to study the degradation of fingerprints, the day where fingerprints will be able to be definitively aged may be ways away. The current experiments have provided methods such as three-dimensional and visual parameters that could potentially find the solution, but also uncovered methods such as immunolabeling and chemical composition that face major challenges. From the statistically point of view, researchers are very close in developing equations that exploit the likelihood ratios of similarity and even calculate the various possible error rates. The evidence found in this review shows that science is one step closer to the age determination of fingerprints.
ContributorsPorter, Lindsey Jordan (Author) / De Alcaraz Fossoul, Josep (Thesis director) / Mancenido, Michelle (Committee member) / School of Criminology and Criminal Justice (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
As human beings we go through the world interpreting – seeing a situation, gathering context, and making a decision on the meaning of the thing we just experienced. The philosopher Martin Heidegger calls this way of being hermeneutics – a practice of interpretation. This method of approach does not ignore a person’s bias, instead bias is highlighted, understood, and possibly even overcome. In the following pages the basic definition and process of hermeneutics will be discussed. Leading into the difference between calculative and meditative thought – scientific and philosophical – in order to later discuss the possibility and need to merge the two in the field of Forensic Science. Forensic Scientist uses hermeneutic thought by way of merging calculative and meditative thinking. In order to support this claim artistic renderings of ‘the pieces of an unknowable whole’ were created to literally illustrate this truth.
Forensic science is tasked with using calculative thinking with scientifically accepted methods of measurement and detection as well as the meditative task of applying their data to messy, real-world events. In order to support my supposition of forensic scientists being hermeneutical workers, three paintings were created. The three paintings can be considered a tryptic of sorts due to the context in which they are presented: forensic science. They each tell a story that is weaved within each other – spatter indicating violence long past, the empty void of a body gone, and the cold decomposition of a victim found. It is the forensic scientist that must interpret each piece separately and is tasked with finding how and why they are put together. The hermeneutical work of the forensic scientist interpreting a crime scene uses the same methods as one who interprets text. A forensic scientist opens possibilities of meaning in the same way that Martin Heidegger’s hermeneutic circle does. There is interplay between the interpreter (the forensic scientist) and the text (the crime scene), questions are formed (what happened here?) and responses are made (evidence found at the scene). This question and response outlook is what make the forensic scientist a hermeneutic thinker.
Forensic science is tasked with using calculative thinking with scientifically accepted methods of measurement and detection as well as the meditative task of applying their data to messy, real-world events. In order to support my supposition of forensic scientists being hermeneutical workers, three paintings were created. The three paintings can be considered a tryptic of sorts due to the context in which they are presented: forensic science. They each tell a story that is weaved within each other – spatter indicating violence long past, the empty void of a body gone, and the cold decomposition of a victim found. It is the forensic scientist that must interpret each piece separately and is tasked with finding how and why they are put together. The hermeneutical work of the forensic scientist interpreting a crime scene uses the same methods as one who interprets text. A forensic scientist opens possibilities of meaning in the same way that Martin Heidegger’s hermeneutic circle does. There is interplay between the interpreter (the forensic scientist) and the text (the crime scene), questions are formed (what happened here?) and responses are made (evidence found at the scene). This question and response outlook is what make the forensic scientist a hermeneutic thinker.
ContributorsCraig, Catherine Anne (Author) / Kobojek, Kimberly (Thesis director) / Watrous, Lisa (Committee member) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The effects that forensic-themed programs such as CSI: Crime Scene Investigation has on the public's understanding and expectations of the criminal justice system has been a main focus of study in recent years. This phenomenon was coined by the media and termed the "CSI Effect." This study aimed to research the correlations between age, gender, and program-watching habits on potential juries' evidence expectations in court. To do so, 70 people were surveyed and asked a series of demographic questions, as well as questions about how often they watch forensic-themed shows and their experience with the criminal justice system. They were given a mock crime scene scenario and asked about their scientific and non-scientific evidence expectations in this particular case. The most notable results showed that a longer exposure time to forensic-themed programs correlated to high evidence expectations. However, how often viewers watch forensic-themed programs did not seem to affect their evidence expectations. It was concluded that the higher evidence expectations by modern jurors may be due to a combination of the "CSI Effect" and the newly hypothesized "Tech Effect," instead of just being the consequence of the watching too much forensic-themed television.
ContributorsJones, Kristin Taylor (Author) / Kobojek, Kimberly (Thesis director) / Lafond, Sue (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor)
Created2014-05
Description
The current study looked at weight stereotype presence and whether certain types of medical professionals held this bias over others. This study also investigated if there was a relation between medical professionals' self-esteem and the presence of the weight stereotype. By having a sample consisting of registered nurses, physician assistants, and medical doctors data was then collected within each group to analyze for any significant differences between the three levels of medical professionals. Eleven participants were guided through participation in the Harvard Implicit Association Test, specifically testing for weight stereotype presence, followed by responses to 50 true/false statements on the Sorensen Self-Esteem Test to measure the self-esteem of each participant. The participants within this study were 11 medical professionals, between the ages of 25 and 59, with 6 women and 5 men. The resulting sample consisted of 6 registered nurses, 3 physician assistants, and 2 medical doctors all currently practicing medicine in the state of Arizona, with the exception of 1 participant who is practicing in Colorado. This study was conducted through Qualtrics, an online database through Arizona State University. Upon completion of the study, 3 different tests were run using the data collected. The first was a between-subjects effect test to determine if there was a difference in stereotype presence among the three levels of medical professionals. The second test was a correlation between stereotype presence and the self-esteem each medical professional displayed. The third was a between-subjects effect test looking at self-esteem differences among the three levels of medical professionals. None of the tests yielded significant results, suggesting that there is no difference in weight stereotype presence or self-esteem among the three groups of medical professionals. The data also suggests that there is no correlation between a medical professionals' self-esteem and weight stereotype presence. Suggestions for future research within this paper have discussed ways to improve the current study in order to create significant results.
ContributorsFisher, Bobbi Paige (Author) / Lewis, Stephen (Thesis director) / Edwards, Alison (Committee member) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
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 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.
ContributorsLittle, Cody Lee (Author) / Kobojek, Kimberly (Thesis director) / Falsetti, Anthony (Committee member) / Ball, Becky (Committee member) / School of Human Evolution and Social Change (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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 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.
ContributorsDowell, Kori Kalei (Author) / Falsetti, Anthony (Thesis director) / Kanthaswamy, Sreetharan (Committee member) / School of Human Evolution and Social Change (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
The subcategory of evidence deemed trace evidence is frequently seen in crime scenes, and while it is commonly the smallest evidence around, that doesn’t stop it from greatly contributing to the findings at the scene. Blood evidence may be categorized into this group in certain cases at crime scenes, especially in cases of transfer between two objects or people. In this study, the transfer of blood across both porous and non-porous substrates was examined to determine the persistence of blood across both substrates. The resulting stains after each trial of transfers were tested with a presumptive blood test commonly used in crime labs, the Kastle-Meyer test. Throughout all trials of the experiment, it was determined that blood on a non-porous surface typically dries faster as long as there isn’t a pooling effect, which hinders the ability for a stain to be continuously transferred and detected by Kastle-Meyer. Conversely, porous substrates are more likely to absorb and retain the blood in the material, allowing the blood to be released when pressure is applied, causing the stain to transfer more easily and result in a stain that will produce a positive Kastle-Meyer result.
ContributorsKincade, Morgan (Author) / Weidner, Lauren (Thesis director) / Kobojek, Kimberly (Committee member) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05