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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
This project details the synthesis and analysis of five analogs of model compound NEt-4IB (6-[ethyl(4-isobutoxy-3-isopropylphenyl)amino]nicotinic acid), that target the retinoid-X-receptor (RXR). These molecules were synthesized by substituting, adding, or removing substituents in the nitrogen-containing ring of NEt-4IB. The parent compound is a RXR partial agonist and has proven to be effective in the treatment of type II diabetes without the unwanted side effects seen with full agonists. Many of the current drugs used to treat type II diabetes are accompanied by adverse effects including increased triglyceride levels, weight gain, and hypoglycemia. Biological evaluation with KK-Ay (obese diabetic) model mice indicates that NEt-4IB may even be more effective than current drugs on the market, like pioglitazone. As a result, it is predicted that due to such structural similarity, the analogs synthesized for this work will perform equally, if not better than, NEt-4IB.
ContributorsMaiorella, Emma Lauren (Author) / Wagner, Carl (Thesis director) / Marshall, Pamela (Committee member) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
In humans, infections, disease, inflammation, and other injuries to specific tissues have been shown to cause delays in the onset of puberty. It is known that steroid hormones and insulin play a role in these delays, yet it is not understood what is happening with the immune system during this response. Similar results have been found in the fruit fly, Drosophila melanogaster, in which damage to adult precursor tissues triggers developmental delays. This project addresses the immune component of the injury response in Drosophila. The goal is to identify which immune response genes, if any, show a significant change in expression after injury. The general methodologies used were first inducing injury via a temperature- sensitive expression of cell death genes in wing precursor tissues, then examining changes in gene expression of immune response genes before and after injury using real-time PCR. The results show that injury increases the expression of genes Drs, CecA1, and Def while decreasing expression of Rel, Dpt, PGRP-LE, and Tl. The changes in immune gene expression following injury suggest the possibility of an immune component to the systemic injury response. These results can further be explored by using mutations of the immune genes to examine their direct effects on the systemic injury response. This research can eventually lead to preventative measures to protect against developmental delays due to infections and diseases in humans.
ContributorsDuprey, Deanna Jeanette (Author) / Hackney, Jennifer (Thesis director) / Marshall, Pamela (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor) / School of Social and Behavioral Sciences (Contributor)
Created2014-12
Description
Rainbowfish, Melanotaenia splendida, are a common freshwater species in tropical regions of the world. They are members of the Atheriniformes (Atherinomorpha), the silverside fishes, which are known for some unusual feeding behaviors. Their close relatives, the Cypriniformes, such as mollies, guppies, and mosquitofish, are well studied and exhibit innovative morphologies associated with feeding. The third member of the Atherinomorphs, the Beloniformes, contains the recognizably odd needlefish, halfbeaks, and flying fishes. As a group, it is fair to say that the Atherinomorpha contain some pretty unusual fishes. The purpose of this project was to gain a further understanding of the unique feeding kinematics of Atheriniform fishes using the rainbowfish as an exemplar species. Feeding kinematics were quantified using high speed video recording unrestrained feeding events. Three feeding events from five individuals were analyzed frame by frame, from the time of the mouth opening to mouth closing. The X,Y coordinates of seven specific points were used to calculate the following kinematic variables: cranial elevation, gape distance, premaxillary protrusion, and hyoid depression. The contribution of cranial elevation to the strike was inconsistent. At times the fish raised the head as they expanded the mouth for prey capture, and at other times they did not. Cranial elevation is theoretically important for expanding the head during suction prey capture. Hyoid depression was more consistent, and clearly contributed to expansion of the head elements. Premaxillary protrusion contributed strongly to the event, and the jaws are closed with the premaxilla still protruded, facilitating a ‘nipping’ style jaw closure. A nipping style of prey capture is much like the Cyprinodontiforms, however, in rainbowfish, the event was quicker, and appeared to rely heavily on suction. We used both cleared and stained specimens and CT scans to investigate the underlying morphology of rainbowfish. These images revealed nearly microscopic teeth on the exterior of the jaws, and other features associated with feeding on highly elusive prey (i.e. prey that are mobile and likely to be able to escape predation). Further examination revealed a surprisingly well developed set of pharyngeal jaws, secondary to the oral jaws. The structure of the pharyngeal jaws suggested that most of the prey processing occurred within the pharynx.
ContributorsLerma, Sarahi (Author) / Ferry, Lara A. (Thesis director) / Hackney Price, Jennifer (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor) / School of Social and Behavioral Sciences (Contributor)
Created2015-05
Description
In recent years, ecologists have begun to study the effects of urbanization on species diversity. While urban areas generally suffer decreased biodiversity, some species, termed “urban exploiters”, not only live in the city but depend on urban resources to thrive. It is hypothesized that urban exploiters may succeed in part due to phenotypic plasticity, in which organisms rapidly adjust their physiology or behavior to adapt to novel environmental contexts. In the city, it may be adaptive to display thermal plasticity, as the urban heat island effect caused by concrete and asphalt infrastructure prevents cooling at night. In this study, we observed the decorated cricket Gryllodes sigillatus, an invasive urban exploiter found in metropolitan Phoenix, in two separate experiments. We hypothesized that heat tolerance and activity are both plastic traits in this species. In Experiment 1, we predicted that knock-down time, a measure of heat tolerance, would be negatively affected by acclimation to a laboratory environment. Our results suggest that heat tolerance is affected by recent thermal regimes and that laboratory acclimation decreases knock-down time. In Experiment 2, we predicted that activity would increase with temperature until a point of extreme heat, at which point activity would decline. Statistical analysis for the second experiment reveals that activity decreases at 33°C, a natural urban extreme. This suggests either that 33°C is a thermal limit to physiology or that G. sigillatus is able to alter its behavior to exploit local thermal heterogeneity.
ContributorsVannan, Annika (Author) / Johnson, James Chadwick (Thesis director) / Angilletta, Michael (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor) / School of Social and Behavioral Sciences (Contributor)
Created2015-05
Description
Virtually all animals require relatively predictable developmental schedules in order to fulfill the cycle of life. Cell death and severe inflammation alter steroid hormone production and can disrupt the timing of developmental transitions such as puberty. In the fruit fly, Drosophila melanogaster, injury to wing precursor tissues has been shown to result in decreased steroid hormone levels and delay development. The effects of damage to other tissues have not yet been explored. Here, the larval salivary glands were damaged in order to observe how injuring these specific tissues affect the timing of developmental transitions. Damage was induced by tissue-specific, temperature sensitive activation of cell death genes. The results indicated that death to salivary gland cells accelerates the Drosophila time to adult eclosion and that the observed acceleration of development is age-dependent. Insight into the effects of injury on development in Drosophila can potentially lead to information about development in other organisms, including humans, following injury or chronic inflammation.
ContributorsRippere, Alicia Leann (Author) / Hackney, Jennifer (Thesis director) / Marshall, Pamela (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor)
Created2015-05
Description
Bexarotene (Targretin®) is an FDA approved drug used to treat cutaneous T-cell lymphoma (CTCL), as well as off-label treatments for various cancers and neurodegenerative diseases. Previous research has indicated that bexarotene has a specific affinity for retinoid X receptors (RXR), which allows bexarotene to act as a ligand-activated-transcription factor and in return control cell differentiation and proliferation. Bexarotene targets RXR homodimerization to drive transcription of tumor suppressing genes; however, adverse reactions occur simultaneously when bound to other nuclear receptors. In this study, we used novel bexarotene analogs throughout 5 iterations synthesized in the laboratory of Dr. Wagner to test for their potency and ability to bind RXR. The aim of our study is to quantitatively measure RXR homodimerization driven by bexarotene analogs using a yeast two-hybrid system. Our results suggests there to be several compounds with higher protein activity than bexarotene, particularly in generations 3.0 and 5.0. This higher affinity for RXR homodimers may help scientists identify a compound that will minimize adverse effects and toxicity of bexarotene and serve as a better cancer treatment alternative.
ContributorsSeto, David Hua (Author) / Marshall, Pamela (Thesis director) / Wagner, Carl (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor) / School of Social and Behavioral Sciences (Contributor)
Created2015-05
Description
TANKED is a novella set in a futuristic world in which fish have become the dominant species and humans are kept in bowls of air. This story follows five children (8-16 years old) on their escape attempt to find the Land Above. While light hearted in nature for the target audience of about 4th grade, the story does cover a variety of themes including religion, perseverance, and climate change. The sibling pair that serves as the two main characters work as a foil between the two ideals of this journey. The younger, Goldie, represents hope and is always optimistic about the escape working while the elder, Swimmy, deems herself as more of a “realist” and often points out the slim likelihood of the events working out in their favor. The strengths of this piece largely involve the characters and their dialogue while a weakness is the scenery descriptions and where the story ends. This story is not over, but instead will one day have a part two. Some difficulties encountered in this piece included the scale of the humans to the fish in scenes like the one in which the group rides the back of a dolphin as well as setting up the world in which people could accept this new world as a futuristic earth. Both of these issues were worked on, but can still persist in some readings of the novella. This project will be worked on in the future to adapt it into a screenplay to accentuate the strengths of the piece and complete the story.
ContributorsSnider, Natasha Rayne (Author) / Amparano Garcia, Julie (Thesis director) / LaCroix, Kristen (Committee member) / School of Mathematical and Natural Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
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