Theses and Dissertations
This collection includes both ASU Theses and Dissertations, submitted by graduate students, and the Barrett, Honors College theses submitted by undergraduate students.
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- Creators: School of Life Sciences
Description
Mammary gland development in humans during puberty involves the enlargement of breast tissue, but this is not true in non-human primates. To identify potential causes of this difference, I examined variation in substitution rates across genes related to mammary development. Genes undergoing purifying selection show slower-than-average substitution rates, while genes undergoing positive selection show faster rates. These may be related to the difference between humans and other primates. Three genes were found to be accelerated were FOXF1, IGFBP5, and ATP2B2, but only the latter one was found in humans and it seems unlikely that it would be related to the differences between mammary gland development at puberty between humans and non-human primates.
ContributorsArroyo, Diana (Author) / Cartwright, Reed (Thesis director) / Wilson Sayres, Melissa (Committee member) / Schwartz, Rachel (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
A literature review summarizing the current status of conservation efforts of the Mojave Desert tortoise (Gopherus agassizii) including a brief overview of the Endangered Species Act (ESA) and its applicability to this species' conservation. A genetic and physiological comparison of the morphologically similar Mojave species with the Sonoran (Gopherus morafkai) species proceeded by an analysis of if and how the ESA should apply to the Sonoran population. Analysis of current plans and interagency cooperations followed by a multi-step proposal on how best to conserve the Sonoran population of Desert tortoise.
ContributorsKulik, Elise Chikako (Author) / Kusumi, Kenro (Thesis director) / Tollis, Marc (Committee member) / Wilson Sayres, Melissa (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
The goal of my study is to test the overarching hypothesis that art therapy is effective because it targets emotional dysregulation that often accompanies significant health stressors. By reducing the salience of illness-related stressors, art therapy may improve overall mood and recovery, particularly in patients with cancer. After consulting the primary literature and review papers to develop psychological and neural mechanisms at work in art therapy, I created a hypothetical experimental procedure to test these hypotheses to explain why art therapy is helpful to patients with chronic illness. Studies found that art therapy stimulates activity of multiple brain regions involved in memory retrieval and the arousal of emotions. I hypothesize that patients with chronic illness have a reduced capacity for emotion regulation, or difficulty recognizing, expressing or altering illness-related emotions (Gross & Barrett, 2011). Further I hypothesize that art therapy improves mood and therapeutic outcomes by acting on the emotion-processing regions of the limbic system, and thereby facilitating the healthy expression of emotion, emotional processing, and reappraisal. More mechanistically, I propose art therapy reduces the perception or salience of stressors by reducing amygdala activity leading to decreased activation of the hypothalamic-pituitary-adrenal (HPA) axis. The art therapy literature and my hypothesis about its mechanisms of action became the basis of my proposed study. To assess the effectiveness of art therapy in alleviating symptoms of chronic disease, I am specifically targeting patients with cancer who exhibit a lack of emotional regulation. Saliva is collected 3 times a week on the day of intervention: morning after waking, afternoon, and evening. Stress levels are tested using one-hour art therapy sessions over the course of 3 months. The Perceived Stress Scale (PSS) assesses an individual's perceived stress and feelings in past and present situations, for the control and intervention group. To measure improvement in overall mood, 10 one-hour art sessions are performed on patients over 10 weeks. A one-hour discussion analyzing the participants' artwork follows each art session. The Spielberger State-Trait Anxiety Inventory (STAI) assesses overall mood for the intervention and control groups. I created rationale and predictions based on the intended results of each experiment.
ContributorsAluri, Bineetha C. (Author) / Orchinik, Miles (Thesis director) / Davis, Mary (Committee member) / Essary, Alison (Committee member) / School of Life Sciences (Contributor) / School for the Science of Health Care Delivery (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Bats (order Chiroptera) are the longest lived mammals for their size, with particularly extreme longevity evolving in the family Vespertilionidae, or vesper bats. Because of this, researchers have proposed using bats to study ageing and cancer suppression. Here, we study gene duplications across mammalian genomes and show that, similar to previous findings in elephants, bats have experienced duplications of the tumor suppressor gene TP53, including five genomic copies in the genome of the little brown bat (Myotis lucifugus) and two copies in Brandt's bat (Myotis brandtii). These species can live 37 and 41 years, respectively, despite having an adult body mass of only ~7 grams. We use evolutionary genetics and next generation sequencing approaches to show that positive selection has acted on the TP53 locus across bats, and two recently duplicated TP53 gene copies in the little brown bat are both highly conserved and expressed, suggesting they are functional. We also report an extraordinary genomic copy number expansion of the tumor suppressor gene FBXO31 in the common ancestor of vesper bats which accelerated in the Myotis lineage, leading to 34\u201457 copies and the expression of 20 functional FBXO31 homologs in Brandt's bat. As FBXO31 directs the degradation of MDM2, which is a negative regulator of TP53, we suggest that increased expression of both FBXO31 and TP53 may be related to an enhanced DNA-damage response to genotoxic stress brought on by long lifespans and rapid metabolic rates in bats.
ContributorsSchneider-Utaka, Aika Kunigunda (Author) / Maley, Carlo (Thesis director) / Wilson Sayres, Melissa (Committee member) / Tollis, Marc (Committee member) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
This paper explores the idea of xenophilia and the circumstances under which it may occur. Xenophilia is the preference for an outgroup member over an ingroup member. This preference does not have to be amicable, and in fact can be exploitative under certain circumstances. Previous research indicates that xenophobia is much more common, but a few researchers have found support for the existence of xenophilia. To experimentally test the circumstances under which xenophilia might occur, I conducted a survey-based experiment on Amazon’s Mechanical Turk. This consisted of directed visualizations that manipulated participant goal (self-protection vs. mate acquisition) and the resources offered by both a fictitious outgroup and the hometown ingroup, followed by measures of ingroup/outgroup preference. I hypothesized that when the resource offered by the group addressed the participants’ goal, they would prefer the group with the “matched” resource—even if it was the outgroup providing that resource. My hypothesis was not supported, as the univariate analysis of variance for preference for the outgroup was not significant, F (2, 423) = .723, p = .486. This may have occurred because the goal manipulations were not strong enough to counteract the strong natural preference for ingroup members.
ContributorsDrury, Margaret E. (Author) / Neuberg, Steven (Thesis director) / Davis, Mary (Committee member) / Kenrick, Douglas (Committee member) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Cardiovascular disease is the leading cause of death in the United States, and classic risk factors only predict half of the variance of cases. In this study, parental overprotection and temperamental negative affectivity both significantly correlated with blood pressure and heart rate, which suggests the importance of examining early life factors when determining one's risk for CVD.
ContributorsCarter, Steven Cross (Author) / Luecken, Linda (Thesis director) / Presson, Clark (Committee member) / Davis, Mary (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor) / School of Life Sciences (Contributor)
Created2013-05
Description
Hepatocellular carcinoma (HCC) is the most common type of liver cancer and has been shown to have genetic factors that contribute to cancer susceptibility. These genetic factors can be studied using Genome-Wide association studies (GWAS), which allow for the assessment of associations between specific biologic markers. Through GWAS, associations can be analyzed to identify genetic components that contribute to the onset of HCC. This study uses an extended version of Pathways of Distinction analysis (PoDA) to identify the subset of SNPs within the Antigen Presentation and Processing Pathway that distinguish cases from controls. Further analysis was performed to explore SNP-SNP association differences between HCC cases and controls using R-squared values and p-values. Three SNPs show significant inter-SNP associations in both HCC cases and controls. Additionally, 4 SNPs showed significant SNP-SNP associations exclusively in the control data set, possibly suggesting that control pathways have a greater degree of genetic regulation and robustness that is lost in carcinogenesis. This result suggests that these SNP associations may contribute to HCC susceptibility.
ContributorsAghili, Ardesher Joshua (Author) / Buetow, Kenneth (Thesis director) / Wilson Sayres, Melissa (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
This work examines one dimension of the effect that complex human transport systems have on the spread of Chikungunya Virus (CHIKV) in the Caribbean from 2013 to 2015. CHIKV is transmitted by mosquitos and its novel spread through the Caribbean islands provided a chance to examine disease transmission through complex human transportation systems. Previous work by Cauchemez et al. had shown a simple distance-based model successfully predict CHIKV spread in the Caribbean using Markov chain Monte Carlo (MCMC) statistical methods. A MCMC simulation is used to evaluate different transportation methods (air travel, cruise ships, and local maritime traffic) for the primary transmission patterns through linear regression. Other metrics including population density to account for island size variation and dengue fever incidence rates as a proxy for vector control and health spending were included. Air travel and cruise travel were gathered from monthly passenger arrivals by island. Local maritime traffic is approximated with a gravity model proxy incorporating GDP-per-capita and distance and historic dengue rates were used for determine existing vector control measures for the islands. The Caribbean represents the largest cruise passenger market in the world, cruise ship arrivals were expected to show the strongest signal; however, the gravity model representing local traffic was the best predictor of infection routes. The early infected islands (<30 days) showed a heavy trend towards an alternate primary transmission but our consensus model able to predict the time until initial infection reporting with 94.5% accuracy for islands 30 days post initial reporting. This result can assist public health entities in enacting measures to mitigate future epidemics and provide a modelling basis for determining transmission modes in future CHIKV outbreaks.
ContributorsFries, Brendan F (Author) / Perrings, Charles (Thesis director) / Wilson Sayres, Melissa (Committee member) / Morin, Ben (Committee member) / School of Life Sciences (Contributor) / Department of Military Science (Contributor) / Barrett, The Honors College (Contributor)
Created2015-12
Description
Hand-coding systems of measuring facial expressions were developed to study and analyze human emotions, but they are time-intensive and thus seldom used. As technology has advanced, new computer software programs, such as Affectiva, were developed to code facial expressions automatically using artificial intelligence and machine learning. Since this technology is still new, Affectiva and its validity remain understudied, and no psychological research has been conducted to compare Affectiva computer coding and hand coding of children’s emotions. The purpose of this study was to compare hand and computer coding of children’s expressions of emotion during a videotaped parent-child interaction. The study answered the following questions: 1) Do hand and computer coding agree?; and 2) Are hand and computer coding in higher agreement for some emotions than others? The sample included 25 pairs of twins from the Arizona Twin Project. Facial expressions were coded from videotape by a trained and reliable human coder and using the software Affectiva. The results showed that hand and computer coded emotion were in agreement for positive, but not negative emotions. Changing the context of the interaction to elicit more negative emotion, and using the same indicators of each emotion in computer and hand coding are suggested to improve the comparison of computer and hand coding.
ContributorsKwok, Connie (Author) / Lemery-Chalfant, Kathryn (Thesis director) / Davis, Mary (Committee member) / Miadich, Samantha (Committee member) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The highly conserved Notch signaling pathway regulates cell-cell communication pathways, cell fate, cell determination, cell death, embryonic development, and adult tissue pathways in metazoans. The Notch receptors and ligands that bind to Notch are single pass, transmembrane proteins that communicate cell to cell via juxtacrine signaling. There are reports of the divergent function and localization of the Deltalike 3 (Dll3) ligand. In Mus musculus (an eutherin mammal) the DLL3 protein inhibits the Notch signaling pathway and is localized in the Golgi apparatus. In contrast, the DLL3 protein from zebrafish, Danio rerio (a teleost) activates Notch and is located on the cell surface. This study will focus on examining the evolutionary pathway/evolutionary similarities, localization, and function of the A. carolinensis dll3 gene in comparison to other vertebrate species. This is important because there is not much known about the evolutionary divergence of the DLL3 A. carolinensis protein, its function in Notch signaling, and its subcellular localization.
Evolutionary analysis of vertebrate DLL3 protein sequences using phylogenetic trees showed that D. rerio and A. carolinensis are more evolutionarily similar in comparison to M. musculus suggesting that they may have similar intracellular localization. However, immunofluorescence staining experiments showed that the A. carolinensis DLL3 protein co-localized significantly with an endoplasmic reticulum (ER) specific primary antibody. Since this protein is localized in the secretory system, similar to that of M. musculus DLL3, it suggests that its function is to inhibit the Notch signaling pathway. Protein sequence alignments were created that suggested that there is a region in the protein sequences where the lizard and mouse sequence are conserved, while the zebrafish sequence simultaneously varies. This region of the amino acid sequence could be responsible for the difference in localization and function of the protein in these two species.
Evolutionary analysis of vertebrate DLL3 protein sequences using phylogenetic trees showed that D. rerio and A. carolinensis are more evolutionarily similar in comparison to M. musculus suggesting that they may have similar intracellular localization. However, immunofluorescence staining experiments showed that the A. carolinensis DLL3 protein co-localized significantly with an endoplasmic reticulum (ER) specific primary antibody. Since this protein is localized in the secretory system, similar to that of M. musculus DLL3, it suggests that its function is to inhibit the Notch signaling pathway. Protein sequence alignments were created that suggested that there is a region in the protein sequences where the lizard and mouse sequence are conserved, while the zebrafish sequence simultaneously varies. This region of the amino acid sequence could be responsible for the difference in localization and function of the protein in these two species.
ContributorsBoschi, Alexis (Author) / Wilson-Rawls, Jeanne (Thesis director) / Newbern, Jason (Committee member) / Wilson Sayres, Melissa (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05