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The stress response facilitates our ability to deal effectively with threatening situations, but exposure to severe or chronic stressors can lead to undesirable neural, physiological, and behavioral outcomes. Chronic stress is associated with structural changes in the rat hippocampus, with corresponding deficits in learning and memory. Recent studies have uncovered

The stress response facilitates our ability to deal effectively with threatening situations, but exposure to severe or chronic stressors can lead to undesirable neural, physiological, and behavioral outcomes. Chronic stress is associated with structural changes in the rat hippocampus, with corresponding deficits in learning and memory. Recent studies have uncovered an inherent neuroplasticity that allows the hippocampus to recover from these stress-induced neural changes. Underlying mechanisms likely involve several different cellular and molecular pathways. In order to gain a more comprehensive understanding of these pathways, we investigated differences in protein expression throughout the timeline of chronic stress and recovery. Male Sprague-Dawley rats were randomly assigned to chronic restraint stress for 6hr/d/10d or 6hr/d/21d, stress for 6hr/d/21d followed by a recovery period of no stress for 10 or 21 days, or a control group. The proteome from the hippocampus of these rats was sequenced using liquid chromatography tandem mass spectrometry (LC-MS/MS) and analyzed. We hypothesized that chronic stress alters interneuronal signaling in the hippocampus by enhancing or attenuating the expression of proteins responsible for synaptic plasticity (functional) and neuronal structure (morphology). So far we have found that structural proteins, such as alpha-internexin, homer protein homolog 3, neurofilament light, and vimentin were significantly altered by chronic stress and recovery. In contrast, proteins necessary for or associated with myelination such as 2',3'-cyclic-nucleotide 3'-phosphodiesterase, myelin-associated glycoprotein, myelin basic protein S, and myelin proteolipid protein were significantly downregulated by chronic stress. Collectively, these results will provide a resource for further investigations into the mechanisms of the brain's recovery from chronic stress.
ContributorsKachemov, Marketta Marilyn (Author) / Orchinik, Miles (Thesis director) / Pirrotte, Patrick (Committee member) / Conrad, Cheryl (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Historically, studies of condition-dependent signals in animals have been male-centric, but recent work suggests that female ornaments can also communicate individual quality (e.g., disease state, fecundity). There has been a surge of interest in how urbanization alters signaling traits, but we know little about if and how cities affect signal

Historically, studies of condition-dependent signals in animals have been male-centric, but recent work suggests that female ornaments can also communicate individual quality (e.g., disease state, fecundity). There has been a surge of interest in how urbanization alters signaling traits, but we know little about if and how cities affect signal expression in female animals. We measured carotenoid-based plumage coloration and coccidian (Isospora spp) parasite burden in desert and city populations of house finches to examine urban impacts on male and female health and attractiveness. In earlier work, we showed that male house finches are less colorful and more parasitized in the city, and we again detected that pattern in this study for males. However, though city females are also less colorful than their rural counterparts, we found that rural females were more parasitized. Also, regardless of sex and unlike rural birds, more colorful birds in the city were more heavily infected with coccidia. These results show that urban environments can disrupt signal honesty in female animals and highlight the need for more studies on how cities affect disease and condition-dependent traits in both male and female animals.
ContributorsSykes, Brooke Emma (Author) / McGraw, Kevin (Thesis director) / Sweazea, Karen (Committee member) / Hutton, Pierce (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
Background: Noninvasive MRI methods that can accurately detect subtle brain changes are highly desirable when studying disease-modifying interventions. Texture analysis is a novel imaging technique which utilizes the extraction of a large number of image features with high specificity and predictive power. In this investigation, we use texture analysis to

Background: Noninvasive MRI methods that can accurately detect subtle brain changes are highly desirable when studying disease-modifying interventions. Texture analysis is a novel imaging technique which utilizes the extraction of a large number of image features with high specificity and predictive power. In this investigation, we use texture analysis to assess and classify age-related changes in the right and left hippocampal regions, the areas known to show some of the earliest change in Alzheimer's disease (AD). Apolipoprotein E (APOE)'s e4 allele confers an increased risk for AD, so studying differences in APOE e4 carriers may help to ascertain subtle brain changes before there has been an obvious change in behavior. We examined texture analysis measures that predict age-related changes, which reflect atrophy in a group of cognitively normal individuals. We hypothesized that the APOE e4 carriers would exhibit significant age-related differences in texture features compared to non-carriers, so that the predictive texture features hold promise for early assessment of AD. Methods: 120 normal adults between the ages of 32 and 90 were recruited for this neuroimaging study from a larger parent study at Mayo Clinic Arizona studying longitudinal cognitive functioning (Caselli et al., 2009). As part of the parent study, the participants were genotyped for APOE genetic polymorphisms and received comprehensive cognitive testing every two years, on average. Neuroimaging was done at Barrow Neurological Institute and a 3D T1-weighted magnetic resonance image was obtained during scanning that allowed for subsequent texture analysis processing. Voxel-based features of the appearance, structure, and arrangement of these regions of interest were extracted utilizing the Mayo Clinic Python Texture Analysis Pipeline (pyTAP). Algorithms applied in feature extraction included Grey-Level Co-Occurrence Matrix (GLCM), Gabor Filter Banks (GFB), Local Binary Patterns (LBP), Discrete Orthogonal Stockwell Transform (DOST), and Laplacian-of-Gaussian Histograms (LoGH). Principal component (PC) analysis was used to reduce the dimensionality of the algorithmically selected features to 13 PCs. A stepwise forward regression model was used to determine the effect of APOE status (APOE e4 carriers vs. noncarriers), and the texture feature principal components on age (as a continuous variable). After identification of 5 significant predictors of age in the model, the individual feature coefficients of those principal components were examined to determine which features contributed most significantly to the prediction of an aging brain. Results: 70 texture features were extracted for the two regions of interest in each participant's scan. The texture features were coded as 70 initial components andwere rotated to generate 13 principal components (PC) that contributed 75% of the variance in the dataset by scree plot analysis. The forward stepwise regression model used in this exploratory study significantly predicted age, accounting for approximately 40% of the variance in the data. The regression model revealed 5 significant regressors (2 right PC's, APOE status, and 2 left PC by APOE interactions). Finally, the specific texture features that contributed to each significant PCs were identified. Conclusion: Analysis of image texture features resulted in a statistical model that was able to detect subtle changes in brain integrity associated with age in a group of participants who are cognitively normal, but have an increased risk of developing AD based on the presence of the APOE e4 phenotype. This is an important finding, given that detecting subtle changes in regions vulnerable to the effects of AD in patients could allow certain texture features to serve as noninvasive, sensitive biomarkers predictive of AD. Even with only a small number of patients, the ability for us to determine sensitive imaging biomarkers could facilitate great improvement in speed of detection and effectiveness of AD interventions..
ContributorsSilva, Annelise Michelle (Author) / Baxter, Leslie (Thesis director) / McBeath, Michael (Committee member) / Presson, Clark (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
Physician-assisted suicide occurs when a physician facilitates a patient's death by prescribing a lethal medication that they understand will be used for the purpose of ending the patient's life. It is a highly contentious subject and, with the recent addition of California to the list of states that allow physician-assisted

Physician-assisted suicide occurs when a physician facilitates a patient's death by prescribing a lethal medication that they understand will be used for the purpose of ending the patient's life. It is a highly contentious subject and, with the recent addition of California to the list of states that allow physician-assisted suicide, is an increasingly relevant subject. Physician-assisted suicide is rarely framed as a healthcare experience, despite being a choice in the process of end-of-life care. The research seeks to bring together the debates about physician-assisted suicide with conversations about health care experiences. The experiences and perspectives of young people are particularly valuable to evaluate now, as their voices will soon be the leaders in the debate over physician-assisted suicide. Within this research, there is an underlying theme of independence of individuals that is present through both the literature review and the body of data collected and analyzed. The study found that there was no significant relationship between the quality of a person's healthcare and their perspectives about physician-assisted suicide.
ContributorsMoeur, Katherine Elizabeth (Author) / Brian, Jennifer (Thesis director) / Graff, Sarah (Committee member) / Stevenson, Christine (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
Aquatic macroinvertebrates can be key contributors to nitrogen (N) and phosphorus (P) cycling in streams. Though they exhibit intense control via trophic interactions and nutrient conversion, they may be influenced by other environmental factors that can determine total excretion-derived N, P, and N:P. Garden Canyon and Ramsey Canyon, two streams

Aquatic macroinvertebrates can be key contributors to nitrogen (N) and phosphorus (P) cycling in streams. Though they exhibit intense control via trophic interactions and nutrient conversion, they may be influenced by other environmental factors that can determine total excretion-derived N, P, and N:P. Garden Canyon and Ramsey Canyon, two streams in the Huachuca Mountain Range in Southern Arizona, USA, host similar insect communities, but only Garden Canyon experiences a seasonal P limitation due to the co-precipitation of phosphate with calcium carbonate (CaCO3) in its benthic substrate (Corman et al. 2015). I performed an analysis of excretion rates of aquatic insects living in these streams to test if the P limitation is reflected in rates that insects recycle nutrients. A lower mean N:P of all insect excretion rates in Garden provides evidence for an ecosystem-scale effect, though the differences in N:P of excretion rates by individual taxa between streams did not support the hypothesis. Attributing excretion rates to actual insect densities in three years reveals that natural-occurring fluctuations in excretion rates can operate on the same magnitude as fluctuations in abundances and causes steep differences in nutrient conversion between streams. Lastly, I found that since these streams support immense insect diversity, they receive excretion-derived N and P from taxa in many different functional feeding groups, which illustrates ecosystem resilience and uniqueness.
ContributorsSanders, Ashley Marie (Author) / Sabo, John (Thesis director) / Cease, Arianne (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Students Organize for Syria (SOS) is the student led initiative for Syria. With 18 registered chapters across the United States, this student organization is targeting a multidimensional cause by different means. Though it is now a national movement, it started off with one group at Arizona State University, with one

Students Organize for Syria (SOS) is the student led initiative for Syria. With 18 registered chapters across the United States, this student organization is targeting a multidimensional cause by different means. Though it is now a national movement, it started off with one group at Arizona State University, with one student. Zana Alattar, founder and student director of SOS, tells the story of how she took an ASU organization, Save Our Syrian Freedom (SOS Freedom), to the national level as SOS. As a pre-medical student, she also combines her work in human rights with her future in healthcare. After all, health and human rights have long maintained a synergistic relationship.
ContributorsAlattar, Zana (Author) / Graff, Sarah (Thesis director) / McClurg, Sharolyn (Committee member) / School of Molecular Sciences (Contributor) / School of Social Transformation (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
Leonardo's anatomical studies of the heart demonstrate the dependency of form and function on one another and that their combined activity leads to a comprehensive understanding of the cardiovascular system. While Leonardo was able to make incredible deductions regarding the heart's anatomy and physiology through the concepts of form and

Leonardo's anatomical studies of the heart demonstrate the dependency of form and function on one another and that their combined activity leads to a comprehensive understanding of the cardiovascular system. While Leonardo was able to make incredible deductions regarding the heart's anatomy and physiology through the concepts of form and function, it is evident that his preconceptions hindered him from realizing the full scope of his individual findings. In this paper, I will evaluate the perception of anatomy, the manner in which anatomical knowledge was acquired, and the resultant traditional understanding of the cardiovascular system during Leonardo's lifetime. Leonardo's drawings of the heart will then be analyzed to determine what conclusions he was able to make regarding the heart's anatomy and physiology. Finally, I will compare Leonardo's findings to the modern understanding of the cardiovascular system. Because Leonardo's anatomical studies were hidden from the world for so long, many of his conclusions regarding the heart did not come to light before other individuals had already begun to reach them on their own. Although he made incredible leaps in the understanding of the cardiovascular system, he made little contribution to modern cardiology. Now Leonardo's work can only be examined retrospectively to determine the accuracies and inaccuracies of Leonardo's conclusions in comparison to our modern understanding.
ContributorsMulligan, Kelly Suzanne (Author) / Codell, Julie (Thesis director) / Martin, Thomas (Committee member) / School of Art (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
Many bacteria actively import environmental DNA and incorporate it into their genomes. This behavior, referred to as transformation, has been described in many species from diverse taxonomic backgrounds. Transformation is expected to carry some selective advantages similar to those postulated for meiotic sex in eukaryotes. However, the accumulation of loss-of-function

Many bacteria actively import environmental DNA and incorporate it into their genomes. This behavior, referred to as transformation, has been described in many species from diverse taxonomic backgrounds. Transformation is expected to carry some selective advantages similar to those postulated for meiotic sex in eukaryotes. However, the accumulation of loss-of-function alleles at transformation loci and an increased mutational load from recombining with DNA from dead cells create additional costs to transformation. These costs have been shown to outweigh many of the benefits of recombination under a variety of likely parameters. We investigate an additional proposed benefit of sexual recombination, the Red Queen hypothesis, as it relates to bacterial transformation. Here we describe a computational model showing that host-pathogen coevolution may provide a large selective benefit to transformation and allow transforming cells to invade an environment dominated by otherwise equal non-transformers. Furthermore, we observe that host-pathogen dynamics cause the selection pressure on transformation to vary extensively in time, explaining the tight regulation and wide variety of rates observed in naturally competent bacteria. Host-pathogen dynamics may explain the evolution and maintenance of natural competence despite its associated costs.
ContributorsPalmer, Nathan David (Author) / Cartwright, Reed (Thesis director) / Wang, Xuan (Committee member) / Sievert, Chris (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
This study investigates how the patient-provider relationship between lesbian, gay, and bisexual women and their healthcare providers influences their access to, utilization of, and experiences within healthcare environments. Nineteen participants, ages 18 to 34, were recruited using convenience and snowball sampling. Interviews were conducted inquiring about their health history and

This study investigates how the patient-provider relationship between lesbian, gay, and bisexual women and their healthcare providers influences their access to, utilization of, and experiences within healthcare environments. Nineteen participants, ages 18 to 34, were recruited using convenience and snowball sampling. Interviews were conducted inquiring about their health history and their experiences within the healthcare system in the context of their sexual orientation. The data collected from these interviews was used to create an analysis of the healthcare experiences of those who identify as queer. Although the original intention of the project was to chronicle the experiences of LGB women specifically, there were four non-binary gender respondents who contributed interviews. In an effort to not privilege any orientation over another, the respondents were collectively referred to as queer, given the inclusive and an encompassing nature of the term. The general conclusion of this study is that respondents most often experienced heterosexism rather than outright homophobia when accessing healthcare. If heterosexism was present within the healthcare setting, it made respondents feel uncomfortable with their providers and less likely to inform them of their sexuality even if it was medically relevant to their health outcomes. Gender, race, and,socioeconomic differences also had an effect on the patient-provider relationship. Non-binary respondents acknowledged the need for inclusion of more gender options outside of male or female on the reporting forms often seen in medical offices. By doing so, medical professionals are acknowledging their awareness and knowledge of people outside of the binary gender system, thus improving the experience of these patients. While race and socioeconomic status were less relevant to the context of this study, it was found that these factors have an affect on the patient-provider relationship. There are many suggestions for providers to improve the experiences of queer patients within the healthcare setting. This includes nonverbal indications of acknowledgement and acceptance, such as signs in the office that indicate it to be a queer friendly space. This will help in eliminating the fear and miscommunication that can often happen when a queer patient sees a practitioner for the first time. In addition, better education on medically relevant topics to queer patients, is necessary in order to eliminate disparities in health outcomes. This is particularly evident in trans health, where specialized education is necessary in order to decrease poor health outcomes in trans patients. Future directions of this study necessitate a closer look on how race and socioeconomic status have an effect on a queer patient's relationship with their provider.
Created2016-05
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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

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