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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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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
Description
Autism Spectrum Disorder is a disorder that makes learning, socializing and daily living much more challenging for affected children and adults because of their atypical behaviors. A few examples of these behaviors are repetitive movements, impulsive actions, inability to communicate in a social setting, and many more. There is a

Autism Spectrum Disorder is a disorder that makes learning, socializing and daily living much more challenging for affected children and adults because of their atypical behaviors. A few examples of these behaviors are repetitive movements, impulsive actions, inability to communicate in a social setting, and many more. There is a stigma behind autism that is caused by those who are not well informed on the disorder. These people lack information, and in the past, it was assumed that the disorder is caused by "bad parenting." The parents are then afraid of social shame brought upon them by their child and neglect or avoid a diagnosis for their child's disorder. This becomes a vicious cycle that has negative effects on the affected individuals and their loved ones. Neglect of a diagnosis may also be caused by misinformation interpreted by the parents as their child develops. The parents do not realize this child developing outside of normal behavioral patterns. Years of research have been done to attempt to alleviate the symptoms of autism and cure the disorder. The Autism and Asperger's Program at ASU has developed a year-long dietary plan that increases supplementation to alleviate nutritional deficiencies in participants with autism. These deficiencies include vitamins, minerals, essential fatty acids, sulfate, carnitine, and digestive enzymes such as sucrase, maltase, and lactase. The participants were also put on a gluten-free casein-free diet toward the end of the study. To test the effectiveness of the treatment, the Severity of Autism Scale (SAS) and Social Responsiveness Scales (SRS) were used. The SAS tested the overall severity of ASD participants by rating them from one to ten, ten being "very severe" in terms of ASD symptoms. The results of this scale were compared at the beginning of the study (day 0) and at the end of the study (day 365). The SRS tested the social responsiveness of participants in the form of overall SRS and five subscales that included awareness, cognition, communication, motivation, and mannerisms. These results were also compared at the beginning and end of the study. After analysis of the data, there seemed to be no correlation between age and severity of autism/social responsiveness of participants. There was also no statistically significant data to suggest that there was a correlation between gender and severity of autism/social responsiveness of participants. However, there was statistically significant evidence that the treatment group did improve over the non-treatment/delayed treatment group in both the SAS and SRS. Neither age nor gender had a significant effect on the effectiveness of the treatment. These positive findings suggest that the integrated dietary
utritional therapy was beneficial, and future research on dietary treatments for autism and other disorders is recommended. This may also further discoveries of affected epigenomes with regards to nutritional treatments in disorders like ASD. The epigenome is the methylation and demethylation of the genome that mediates gene expression.
ContributorsGutgsell, Crystal Megan (Author) / Adams, James (Thesis director) / Pollard, Elena (Committee member) / School of Life Sciences (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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Description
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
Description
As part of a group project, myself and four teammates created an interactive children's storybook based off of the "Young Lady's Illustrated Primer" in Neal Stephenson's novel The Diamond Age. This electronic book is meant to be read aloud by a caregiver with their child, and is designed for reading

As part of a group project, myself and four teammates created an interactive children's storybook based off of the "Young Lady's Illustrated Primer" in Neal Stephenson's novel The Diamond Age. This electronic book is meant to be read aloud by a caregiver with their child, and is designed for reading over long distances through the use of real-time voice and video calling. While one part of the team focused on building the electronic book itself and writing the program, myself and two others wrote the story and I provided illustrations. Our Primer tells the story of a young princess named Charname (short for character name) who escapes from a tower and goes on a mission to save four companions to help her on her quest. The book is meant for reader-insertion, and teaches children problem-solving, teamwork, and critical thinking skills by presenting challenges for Princess Charname to solve. The Primer borrows techniques from modern video game design, focusing heavily on interactivity and feelings of agency through offering the child choices of how to proceed, similar to choose-your-own-adventure books. If brought to market, the medium lends itself well to expanded quests and storylines for the child to explore as they learn and grow. Additionally, resources are provided for the narrator to help create an engaging experience for the child, based off of research on parent-child cooperative reading and cooperative gameplay. The final version of the Primer included a website to run the program, a book-like computer to access the program online, and three complete story segments for the child and narrator to read together.
ContributorsLax, Amelia Ann Riedel (Author) / Dove-Viebahn, Aviva (Thesis director) / Wetzel, Jon (Committee member) / 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