More than 30,000 theses and dissertations produced at the University of Arizona are included in the UA Theses and Dissertations collections. These items are available open access, and are full-text searchable. A small percentage of items are under embargo (restricted).

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Recent Submissions

  • Conservation Easements in the Madrean Archipelago: Landscape-Scale Strategy or Random Acts of Conservation?

    Rawoot, Damian Nabil (The University of Arizona., 2017)
    In mixed-jurisdiction landscapes of the Intermountain West, unprotected wildlands in private and State Trust ownership buffer protected areas, support ecosystem and watershed processes, and maintain landscape connectivity, while their subdivision and development, results in losses of habitat and biodiversity, fragmentation, and isolation of neighboring protected areas. In recent decades, conservation easements (CEs) have emerged as the primary tool for protecting private lands, but as private agreements, there is no explicit expectation that land protected provides these conservation values. With this dependence on CEs, identifying their conservation outcomes is critical to understanding their role in landscape-scale conservation efforts. Focusing on the Madrean Archipelago in Arizona and New Mexico, I conducted a mixed methods study assessing the spatial pattern of existing CEs relative to grasslands, riparian areas, and distance from protected areas, and completed stakeholder interviews to identify any process underlying these spatial patterns. Results show that more than 10% of private wildlands in the region are in CEs. They exhibited a strong affinity towards grasslands (almost 20% of private grassland area is in CEs) and protected areas (more than 80% of CEs lie within 1 km of a protected area) but tend to avoid riparian areas. Interviews revealed a moderate level of consistency between the spatial patterns identified and stakeholder objectives. These results suggest that CEs in the Madrean Archipelago do support landscape-scale conservation outcomes, in part because stakeholders engaged in establishing them are prioritizing resources and values with landscape-scale significance. They also affirm the need for more access to spatial data on CEs to better integrate them into regional conservation planning efforts.
  • Exploring the Success and Defeat of Ronda Rousey: A Content Analysis of Twitter and Newspaper Coverage from 2014-2016

    Mikelonis, Ashley (The University of Arizona., 2017)
    Scholarly research has analyzed how female athletes use their social media platforms and how they are represented in news media coverage. However, no scholarly literature has specifically looked at Ronda Rousey, an American mixed martial artist. The current study used a quantitative content analysis to examine how Rousey has utilized her Twitter account as well as how local and national newspapers in the United States framed coverage of Rousey between 2014 to 2016. For the tweets, content, referring to pictures that Rousey posted, was the most popular category; the second most prevalent category was promotional, referring to tweets that promoted upcoming events or sponsorships. Rousey mainly used her Twitter to post pictures of herself and promote her personal brand. For the newspaper articles, the most frequently used frames were agency, powerless, and goals and ambitions. Two new frames emerged from the current study – fame, referring to Rousey’s film career, and relations, referring to Rousey’s personal life and relationships. The newspapers were predominantly neutral in their coverage of Rousey throughout the three-year study period. This case study is important because it found that Rousey was framed in a way that differed from previous research. The findings in this study demonstrate that Rousey was not marginalized in newspaper coverage or portrayed in a negative manner, as other female athletes have been in the past. Rather than focusing on her appearance or sexuality, the news coverage highlighted Rousey’s success and athletic achievements.
  • Murakami Haruki: A Serious Literature Writer Under the Cover of Pop Culture

    Li, Chengyuan (The University of Arizona., 2017)
    As a famous contemporary writer, Murakami Haruki has a wide-reaching influence throughout the world, especially in East Asia. In my thesis, I intend to analyze his novels and short stories from 1979 to 2014. In doing so, I will reveal why Murakami Haruki is so popular in Asia, particularly China. This analysis will demonstrate that East Asian public culture has been undergoing changes during the past 20 years. I will analyze four of Murakami’s works: Wild Sheep Chase (1982), Norwegian Wood (1987), to The Wind-up Bird Chronicle (1995), and finishing with Colorless Tsukuru Tazaki And His Year Of Pilgrimage (2013). Though the evolution of his works, Murakami makes it clear that Japanese society has been under transformation since World War II. After the end of the war, this society changed from a capitalist to cosmopolitan one. I will also discuss how his novels are associated with China, as well as his works’ adaptation in China and among Chinese readers. Since becoming famous, Murakami’s work has been highly criticized. These criticisms has come primarily from Komori Yōichi, Fujii Shozo, Kuroko Kazuo and Kato Norihiro. By discussing these critics, I want to reveal the true meaning for Murakami to be a writer and why I consider him as a serious literature writer under the cover of pop culture.
  • Assessing the Habitat of Coccidioides Posadasii, the Valley Fever Pathogen: A Study of Environmental Variables and Human Incidence Data in Arizona

    Mann, Sarina N. (The University of Arizona., 2017)
    Coccidioidomycosis, or Valley Fever, is an infectious disease caused by inhalation of soil-dwelling fungus Coccidioides posadasii spores in the Lower Sonoran Life Zone (LSLZ) in Arizona. In the context of climate change, the habitat of environmentally-mediated infectious diseases, such as Valley Fever, are expected to change. Connections have been drawn between climate and Valley Fever infection. The operational scale of the organism is still unknown. Here, we use climatic variables, including precipitation, soil moisture, and temperature. We use PRISM precipitation and temperature data, and Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) as a measure of soil moisture for the entire state of Arizona, divided into 126 primary care areas (PCA). These data are analyzed and regressed with Valley Fever incidence to determine the effects of climatic variability on disease distribution and timing. This study confirms that Valley Fever occurrence is clustered in the LSLZ. Seasonal Valley Fever outbreak was found to be variable year-to-year based on climatic variability. The inconclusive regression analyses indicate that the operational scale of Coccidioides is smaller than the PCA region. All variables are related to Valley Fever infection, but one variable was not found to hold more predictive power than others.
  • Fast Automatic Segmentation of Thalamic Nuclei

    Thomas, Francis Tyson (The University of Arizona., 2017)
    Fast, automated segmentation of the thalamic nuclei in the brain has long been desired as it provides for direct visualization of the target for certain procedures like Deep Brain Stimulation (DBS) that target a specific nucleus. It is also beneficial in the study of other pathologies that pertain to different nuclei. In this thesis, a novel approach to fast automated segmentation of thalamic nuclei called Shortened Template and THalamus for Optimal Multi Atlas Segmentation (ST THOMAS) was developed using the multi-atlas segmentation approach. It was designed with a focus on robustness and speed by making use of an averaged template for registration and cropping the inputs and the template. The performance of ST THOMAS was first evaluated on 7T MRI data by comparing with manual delineation (ground truth) by an expert neuroradiologist. Dice coefficients and Volumetric Similarity Indices were used as metrics. To extend the applicability of this method, 3T MRI data were also evaluated. Finally, applications to real time ventralintermideiate (VIM) nucleus targeting for DBS and study of the effects of alcoholism are demonstrated.
  • Lyapunov-Based Control of Coupled Translational-Rotational Close-Proximity Spacecraft Dynamics and Docking

    Wenn, Chad (The University of Arizona., 2017)
    This work presents a non-linear control strategy for the docking of two spacecraft in a leader-follower orbit pattern. The chief craft is assumed to be in a circular orbit around a celestial body. The deputy craft is assumed to have a separation distance from the chief that is small compared to the orbital radius of the chief. Furthermore, the relative dynamics of these crafts can be described by the Hill-Clohessy-Wiltshire equations. The control strategy developed is able to regulate the relative translational distance and velocity of the docking feature points on the two craft with globally asymptotic stability. Furthermore, the control strategy is able to regulate the relative rotational velocity and relative attitude, between the two craft, to that which it is required for successful docking. The rotational control is achieved with “almost” globally asymptotic stability, inclusive of an infinitesimally small unstable manifold. Other researchers in this field have shown that this unstable manifold is easily avoided using advanced control methods. These control laws are developed using Lyapunov’s Direct Method, and have asymptotic stability claims per the use of the Mukherjee-Chen theorem. Numerical Monte-Carlo simulation shows asymptotic stability for a subset of the domain of convergence for the developed control laws. Un-modeled torques and accelerations are later imposed on the system. The control laws are then augmented with integral feedback terms, and the closed loop system, with the augmented control laws, retains the asymptotic stability claims.
  • Application of Industrial Wastewater Effluent in Growth of Algae -- Effects of Heavy Metals on the Growth Rate, Fatty Acid and Lipid Content of Chlorella Sorokiniana and Scenedesmus Obliquus

    Udeozor, Jude Onyeka (The University of Arizona., 2017)
    Growing interest in biofuel production from non-fossil fuel sources has resulted in several studies exploring different raw material sources as feedstock, including many algae species, for large-scale production of biofuel. Algae are promising feedstock due to advantages such as its short growth cycle, high biomass production, and lipid content. However, there are still challenges to overcome in order to use algae for commercial biofuel production. One of these challenges is the requirement for a large quantity of water and nutrients needed for growing large quantities of the algae. This work explores a potential solution to this challenge by studying the possibility of using industrial wastewater to grow algae for biofuel production. However, many industrial wastewaters, including effluents from semiconductor processing plants, are known to contain heavy metals that are toxic to humans and the environment. In this work, the effects of four of such metals ions, As(V), As(III), Ga(III), and In(III) on Chlorella sorokiniana and Scenedesmus obliquus strains were studied. In particular, the heavy metal toxicity on the strains, effects on its growth rate, biomass yield, lipid content and fatty acid methyl esters (FAME) were studied. Also, the effect of controlling pH on growth rate, biomass yield, lipid content, and FAME was studied for Chlorella sorokiniana in the presence of Ga(III). The results of the study confirmed the toxicity of these metals on both strains. However, Ga(III) and In(III) had the highest effect, while As(V) showed the least toxicity to the strains, with Chlorella sorokiniana withstanding concentrations of As(V) as high as 140mg/L. The heavy metals were slightly more toxic to Scenedesmus obliquus compared to Chlorella sorokiniana. In addition, the heavy metals reduced the growth rate of both strains. High percent changes in growth rate (more than 50%) were seen in cultures containing Ga(III) and In(III). Furthermore, concentration measurements with Inductively Coupled Plasma Optical Emission Spectrometer (ICP) before, during, and at the end of the growth period, showed that Scenedesmus obliquus adsorbed higher amounts of the heavy metals compared to Chlorella sorokiniana. Microalgae biosorption of heavy metals limits its end use, hence making Scenedesmus obliquus a less favorable option for this study, but may be a better choice for wastewater treatment applications. The effects of the four metals on the lipid content and FAME profile of Chlorella sorokiniana were studied. The result showed an increase in Chlorella sorokiniana lipid content in the presence of In(III), but a decrease in the presence of As(V) and As(III). The heavy metals had effects on the strain’s FAME compositions. The fatty acid composition included C16:0, C16:1, C16:2, C16:3, C18:0, C18:1, ω-6, C18:2, ω-6, and C18:3, ω-3 accounting for more than 97% of the total FAME composition. Furthermore, controlling the pH of the culture in the presence of Ga(III) at 6.5 led to higher adsorption of the heavy metal, increase in lipid content, but no significant change in FAME composition.
  • Study, Evaluation, and Applications of MRI Contrast Agents that Work Based on CEST and T2-EX Mechanisms

    Daryaei, Iman (The University of Arizona., 2017)
    MRI is a powerful imaging method that offers several advantages including non-ionizing radiation, significant depth of penetration, and great spatial resolution. Current demand for precision medicine and the movement toward personalized medicine have encouraged researchers in the field of medical imaging to develop MRI-based techniques. Various techniques are now available for molecular imaging by MRI. MRI started by utilizing T1 relaxation properties of molecules but soon after other relaxation mechanisms such as T2 and recently Chemical Exchange Saturation Transfer (CEST) were developed. Each of those MRI techniques offers advantages and disadvantages such as differences in experimental procedures, complexity of the method, selectivity and specificity of signals, and translation into clinical applications. We have been developing MRI techniques and responsive contrast agents for CEST MRI in the Pagel laboratory (Contrast Agent and Molecular Imaging Laboratory, also called CAMEL) for the past decade. We have mainly utilized MRI techniques and responsive contrast agents to detect and measure cancer biomarkers. Detection of the activity of enzymes and measurement of pH have been our main focus, and we have developed catalyCEST MRI probes and techniques for the detection of the activity of enzymes and acidoCEST for the measurement of pH. My research started with investigation on paramagnetic agents as potential CEST MRI probes (paraCEST) and continued with an investigation on diamagnetic agents (diaCEST). I completed several projects in which I prepared and evaluated paraCEST and diaCEST contrast agents for the detection of DT-diaphorase, and alkaline phosphatase enzymes, respectively. Although CEST MRI was my main activity in CAMEL, I started a new direction in CAMEL after encountering a series of observations that were unexplainable with CEST MRI. Through my research, I introduced a new class of responsive contrast agents based on the T2-Exchange (T2-Ex) relaxation mechanism. I employed the T2-Ex mechanism to evaluate responsive contrast agents for the detection of nitric oxide biomolecule and nitroreductase enzyme. My research activities in the CAMEL group resulted in one review paper, one book chapter, two published research articles, and two submitted research manuscripts at the time of preparing my PhD dissertation. In addition to my projects, I was involved in another project that focused on nanocapsule drug delivery, which resulted in a second author publication.
  • Generalizability of Universal Screening Measures for Behavioral and Emotional Risk

    Tanner, Nicholas Andrew (The University of Arizona., 2017)
    Data derived from universal screening procedures are increasingly utilized by schools to identify and provide additional supports to students at-risk of behavioral and emotional concerns. As screening has the potential to be resource intensive, effort has been placed on the development of efficient screening procedures, namely brief behavior rating scales. This study utilized classical test theory and generalizability theory to examine the extent to which differences among students, raters, occasions, and screening measures affect the meaningfulness of data derived from universal screening procedures. Teacher pairs from three middle school classrooms completed two brief behavior rating scales during fall and spring screening administrations for all students in their respective classrooms. Correlation coefficients examining interrater reliability, test-retest reliability, and concurrent validity were generally strong. Generalizability analyses indicated that the majority of variance in teacher ratings were attributable to student differences across all score comparisons, but differences between teacher ratings for particular students accounted for relatively large percentages of error variance among student behavior ratings. Although decision studies showed that increasing the number of screening occasions resulted in more generalizable data, the impact of increasing the number of raters resulted in more efficient screening procedures.
  • Chemical and Microbial Processes for Rhodium Recovery

    Zhu, Kechen (The University of Arizona., 2017)
    This is the first report that demonstrates the ability of anaerobic methanogenic granular sludge to reduce Rh(III) to Rh(0). Recovery of rhodium(Rh) during anaerobic incubations under abiotic and biotic condition with different electron donors was studied. H2 and formate reduced Rh(III) to Rh(0) nanoparticles(NPs) in the absence of microorganisms. However, the presence of microorganism was crucial for Rh(III) reduction with ethanol. Results of X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) confirmed the formation of Rh(0) NPs and indicated the localization and morphology of the formed Rh(0) NPs varied with electron donor utilized. Rh(III) reduction with H2 and ethanol obeyed 1st order kinetics. Rh(III) caused a moderate inhibition to methanogenesis. Rh(III) reduction often ceased before coming to completion but this effect is not due to unfavorable thermodynamics. A hypothesis was developed which ascribes the biological reduction of Rh(III) with ethanol as being due to the biological formation of H2 (that subsequently chemically reacts with Rh). The results obtained indicate the potential of utilizing anaerobic granular sludge bioreactor technology as a practical and promising option in Rh(III) recovery.
  • Han Opera as a Public Institution in Modern Wuhan

    Long, Lingqian (The University of Arizona., 2017)
    Wuhan Han Opera Theater (WHOT, formerly Han Opera) is a 400-year old regional opera based in Wuhan, in Hubei Province, in China. WHOT’s recent designation as a public institution under China's neoliberal creative economy initiative to enter the global market has necessitated its transformation from a cultural institution (wenhua jigou) into a creative industry (wehua chanye). As such, WHOT must now create adaptive strategies, alter traditional conventions of performance, infrastructure, education and community presence, reconstitute traditional social functions at the national level, and most importantly, manage a relationship with the government that is entirely novel for both. In the summer of 2016, WHOT participated in two government-led projects: Opera into Campuses and the Chinese National Arts Fund. These programs were the focus of my ethnographic fieldwork, to identify possible effects of the creative economy initiative on a traditional musical institution. Specifically, inquiry was made as to whether and how creative musical and organizational adaptations were being decided, implemented and executed, and as to how the outcomes of these adaptations were being evaluated. Despite using an ethnographic approach, findings from the preliminary study were found to be much more broadly generalizable and applicable across disciplines than expected. As a result, this thesis makes the following arguments: for modernization of an institution of traditional music to be effective, a relationship must exist whereby the transitioning institution is given creative license to generate continued socio-cultural productivity through its creative class ("talent") in joint cooperation with, rather than dependence on, government agencies. The goal must be to revitalize rather than simply preserve such an institution, and to avoid cultural attrition of unique musical qualities of the institution.
  • Human Rights on the U.S.-Mexico Border: The Work of Cultivating Imagined Empathy

    Araibi, Reyna Imad (The University of Arizona., 2015)
    As thousands of undocumented migrants continue to die and disappear in the borderlands of the U.S., human rights NGOs are struggling to mobilize a socially and geographically distant American audience to see this crisis as a human rights matter and act upon it with according urgency and gravity. But why, in the face of immense human suffering on the border, have we not recognized this as a human rights crisis? Furthermore, how can human rights NGOs working on the border address this debilitating challenge? This thesis draws on the historical development of human rights concepts in 18th century Europe as well as on contemporary discourse around ethical humanitarian communication to argue that suffering is only seen as a human rights issue when feelings of imagined empathy are cultivated within distant audiences. Imagined empathy is cultivated through particular practices of representing suffering, practices that focus on the individual autonomy and emotion of the subject, enabling viewers to see themselves in community with the otherwise distant "other". The work of human rights NGOs trying to use human rights to affect social and political change is to, in their positions as witnesses and partners with primary communities, represent suffering to cultivate imagined empathy. The question then remains, what are the specific practices of representation that cultivate imagined empathy and why are they so fundamental to human rights NGO communication?
  • Insect Behavior Determines Plant Distribution in Alpine Habitat

    Alexandre, Nicolas M. (The University of Arizona., 2015)
    Specialist leaf-mining fly Scaptomyza nigrita is a major herbivore of its host plant Cardamine cordifolia. Host plants are found along a gradient from sun-exposed bog to deep spruce shade habitat where herbivory decreases as shade increases. Prior studies have failed to support the hypothesis that plant quality determines plant distribution. A series of outdoor cage experiments utilizing a factorial design tested whether herbivore choice may instead drive plant distribution. It was found that adult female S. nigrita exhibited a significant preference for feeding and ovipositing on C. cordifolia leaves exposed to light, regardless of habitat origin of plant, leaf width, or presence of prior herbivore damage. This study does not support the phytocentric explanation that host plant distribution is determined by herbivore preference for plants based on their quality. My findings instead support the hypothesis that herbivores drive plant distributions into the shade by creating enemy-free space for host plants through their preference for light.
  • Regional Planning Solutions to Changing the Culture of Water Consumption in Phoenix, Arizona

    Clark, Janine Genevieve (The University of Arizona., 2015)
    Arizona has put time and effort into drought preparation—with water banking, surface water storage, and laws to dictate water planning for future developments. However, these securities are stretched thin and weakened by the wake of Arizona's rapid development. In this paper I will focus on the state catalyst for growth, and precedent for political decisions: Phoenix. With a political-economic foundation rooted in a culture of consumption, Phoenix has enabled boundless growth within its impermanent borders—gaining population and short-term economic benefits, while losing its unique desert identity. If adjustments are not made to current means of allocation and rates of demand, Phoenix will face a supply gap in the future. These issues are compounded by climate change, which threatens the longevity of surface water supplies. This paper will outline the strengths and highlight the shortfalls of previous water policies and projects, then discuss threats to available supplies. Embodying a desert identity and embracing conservation in both the urbanized area and economy will be key to the future success of Phoenix, as the necessary changes in policies that link water and land use planning will not be possible without an engaged public base.
  • Chemical Transformations Supported by the [Re₆(μ₃-Se)₈]²⁺ Cluster Core

    Corbin, William C. (The University of Arizona., 2015)
    Hexanuclear transition metal clusters are a distinct class of chemical compounds that have some very interesting chemical and physical properties. Of recent interest in this field has been the [Re₆(μ₃-Se)₈]²⁺ cluster core. This Lewis acidic cluster core contains six substitutable coordination sites, and site differentiation can be accessed through protecting group ligands. The Lewis acidity has been shown to activate unsaturated cluster-bound ligands, and the expanded atom-like structure and high symmetry of the cluster core has potential use in synthesizing some fascinating and novel hybrid materials. Little work has been performed in establishing the scope of these chemical transformations. The work herein describes the efforts and successes of such work. Chapter 1 provides the essential background required for understanding the [Re₆(μ₃-Se)₈]²⁺ cluster core's synthesis, properties, and currently known research directions and successes. This chapter first introduces hexanuclear clusters in a general format, then focuses on the established catalytic and material capabilities that have been determined using this specific cluster core. Chapter 2 discusses the synthesis, characterization, and hydrogen-bonded assemblies formed from [Re₆(μ₃-Se)₈]²⁺ cluster-isonicotinic acid cluster complexes. These complexes have potential uses as hybrid inorganic/organic linkers for the generation of luminescent Lewis acidic metal-organic frameworks (MOFs). Prospective applications of such materials include catalysis, separations, and gas storage. Chapter 3 focuses on the novel chemistry of [Re₆(μ₃-Se)₈]²⁺ cluster-activated CH₃CN with N-based nucleophiles to form acetamidines. These ligands are of interest due to their use in medicinal chemistry, CO₂/CS₂ sequestration, and the formation of synthetically-relevant species. Quantitative yields are obtained and single-crystal XRD analyses reveal specific stereochemical outcomes. Trifluoroacetic acid (TFA) in a cluster-amidine CH₃CN solution removes the ligand as the acetamidinium TFA salt, and the starting cluster solvate is reproduced making a recyclable catalyst. Chapter 4 expands on a project similar to that of chapter 3, except that O-based nucleophiles are utilized for specific cluster isomers. The newly formed ligands, imino esters, are of interest in organic synthesis as valuable starting materials for the generation of β-lactams and heterocycles. ³¹P NMR and single–crystal XRD reveal Z stereochemistry is preferred in the cis isomer, but conflicting results for the hexasubstituted isomer leave stereochemical analyses unresolved. Chapter 5 attempts to incorporate the chemistry established in chapters 2-4 to provide some fresh and interesting research outlooks possible with the [Re₆(μ₃-Se)₈]²⁺ cluster core. Incorporation of the cluster into MOFs is discussed, and the possibility of post-synthetic modifications for metal sequestration, catalysis, and sensing is explained. Appendix A provides all the NMR data obtained for synthesized materials with peak picks and integrations provided. Appendix B entails all crystallographic information for structures determined after syntheses. Appendix C provide high-resolution mass spectra.
  • A Computational Framework to Determine the Mechanical Properties of Ocular Tissues and a Parametric Study on their Effects on the Biomechanical Response of Lamina Cribrosa

    Ayyalasomayajula, Avinash (The University of Arizona., 2015)
    As is the case with many ocular neuropathies, primary open-angle glaucoma (POAG) leads to an irreversible damage to the visual field. Loss of visual field first occurs in the peripheral vision and slowly propagates towards the middle. Although there are differences in its rate of incidence, glaucoma is projected to be the leading cause of blindness, second only to cataract, affecting significant percentage of populations across different age, race/ethnic groups. A hallmark of POAG is the dysfunction of retinal ganglion cells (RGCs) which connect to the axons which, in turn, relay the visual information from the eye to the brain. Previous research has shown that axonal density in the optic nerve head (ONH) is greatly reduced due to chronically elevated intraocular pressure (IOP). IOP-lowering treatment has been shown to reduce the visual field loss, and continues to be the dominant treatment methodology for glaucoma. Previous research has shown that the biomechanics of the lamina cribrosa (LC) - a highly porous tissue through which the axons carrying the visual information exit the eye, is important in influencing the viability of the RGCs. In a normal eye, the LC is primarily made up of collagen of types I, III, and IV which encompass (specifically, arranged circularly) the axon shafts and the blood vessels (1). In addition to elevated IOP, changes in the material properties of ocular tissues in and around the ONH region, which include peripapillary sclera and LC, could affect its biomechanics, which could be a result of changing microstructure and morphology of these tissues, and may contribute to POAG. The current work is aimed at creating computational models to incorporate the complex nature of ocular tissues, and develop computational techniques to characterize the variation in the material properties of ocular tissues (which include the tissue moduli, fiber orientation, permeability etc.), and study the effects they have on the biomechanical response of the LC region.
  • Developing Content for an Online Virtual Interactive Simulation Case for Cultural Competency of Nursing Students in Caring for Puerto Ricans in New York City: A Community Based Participatory Research Approach

    Mathew, Lilly (The University of Arizona., 2015)
    With growing cultural diversity in the United States (U.S.), health disparities continue to exist among many ethnic minority populations impacting the U.S. economy. Health disparities are health differences that are noted in a particular cultural group in respect to higher rates of diseases and deaths in comparison to others. These cultural groups have common attributes and can be based on race, ethnicity, disability, sexual orientation, income, residential location and many others. One such example is individuals of Puerto Rican heritage, the second largest Hispanic group living in the U.S. mainland. Puerto Ricans are identified to have multiple health disparities in comparison to other Hispanic and non-Hispanic population groups living in the U.S. Among other factors, common cultural health care beliefs and practices of individuals impact health outcomes. Healthcare professionals like nurses are expected to provide culturally competent care to vulnerable populations with known health disparities. Culturally competent care refers to delivering care congruent with patients' cultural beliefs and practices. Therefore, it is important to educate health professionals regarding caring for vulnerable populations. The purpose of this community-based participatory research (CBPR) study was to develop content for an educational tool, an online virtual interactive simulation (OVIS) case for developing cultural competency of nursing students in caring for the Puerto Rican population of New York City (NYC). The content development for OVIS was guided by the framework for Cultural Competency Simulation Experiences (CCSE), which was developed as a part of this dissertation. The CCSE framework guided the content development of OVIS using a CBPR approach. A community advisory board was developed which consisted of cultural, clinical and educational experts, residing in New York and Puerto Rico.
  • Causes and Consequences of Plant Responses to Environmental Change over Physiological, Ecological, and Evolutionary Time

    Sloat, Lindsey Leigh (The University of Arizona., 2015)
    Assessing how environmental change affects plants is increasingly important as terrestrial ecologists attempt to predict future patterns from current processes. However, this challenge is complicated because plant communities can respond to environmental variation at different, but overlapping scales. Additionally, both patterns and the processes that drive them are sensitive to the methods that scientists use to study them. Consequently, a variety of experimental and theoretical approaches are necessary to improve our understanding of how organisms, communities, and ecosystems will respond to future change. Collectively, the studies in this thesis employ a diverse array of approaches to test important ecological theories, including long-term observational studies, manipulative experiments, and analyses that leverage both local and global datasets. The Enquist lab has been measuring subalpine meadow carbon fluxes and climate variables at the Rocky Mountain Biological Laboratory (RMBL), for over 13 years at the time of this writing. Examining correlations between climate and carbon flux over this time has led to the identification of interesting patterns between snowmelt, precipitation events, and rates of carbon exchange. Despite the longer growing season, early snowmelt dates ultimately result in lower productivity in these systems. Pairing this study with the results of a soil moisture manipulation experiment aided in the discovery that the strength and duration of the foresummer drought was directly related to rates of carbon exchange and biomass accumulation in these systems. Thus, integrating long-term observational work with an experimental manipulation served to link pattern and process in a way that was not possible with either study alone. The studies in this thesis range in scale from sub-organismal (chapter 3), to community ecosystem (chapters 1 and 2), to continental (chapter 4). Across all scales afunctional trait ecology approach contributes a holistic view of how these changes may impact organismal, ecosystem, and evolutionary responses to environmental variation. Plants are frequently faced with fundamental performance tradeoffs, which arise due to physical, chemical, genetic/evolutionary, and/or ecological constraints. As a result, functional trait measurements can reflect ecological strategies or resource acquisition strategies. Functional ecology offers a promising approach to linking the attributes of individuals to and communities to ecosystem processes. Understanding how individuals, communities, and ecosystems will respond to environmental change is a fundamental question in ecology. I address this topic using a variety of novel experimental methods and statistical techniques. I use a functional ecology approach by considering not only the species in a community, but also the distribution of functional traits that those species represent. It is in this way that I test ecological hypotheses regarding plant responses to environmental change over physiological, ecological, and evolutionary time scales.
  • A Study to Examine the Feasibility of an Integrative Approach to Interventions in Reducing Anxiety

    Parmar, Rajni (The University of Arizona., 2015)
    Background: Magnetic resonance imaging (MRI) related anxiety is a multidimensional phenomenon with symptoms that include claustrophobia, fear of being hurt, fear of the unknown, and fear about results, and often causes patients to move during their MRI examination resulting in motion artifacts leading to the need for repeat scans and translating into poor quality of care, increasing costs, and declining workflow efficiency. Although most facilities performing MRIs use various techniques in an attempt to reduce anxiety, new interventions are needed to improve patient support. Objective: The purpose of this feasibility study in patients undergoing MRI was to (1) determine recruitment rates; (2) determine adherence to touch and foot massage interventions; (3) determine provider and participant's acceptability of physical presence, human touch or foot massage interventions; and (4) examine the effects of touch or foot massage interventions as compared to physical presence during MRI on anxiety. Methods: A quasi-experimental design was used for this feasibility study where the interventions were foot massage and touch. For the control group, the researcher remained in the room with the patient. Recruitment of the sample (N=60) was done from the Center for Neurosciences (CNS). In addition to measuring provider and participant acceptability, anxiety was assessed using a single item verbally administered anxiety rating (VAR) scale. Results: Recruitment of participants from the CNS generated a recruitment rate of 78.2%. There were no barriers to the application of the intervention protocol. The overall mean value of effectiveness was 8.53, SD = 2.4. There was a significant difference among the three groups in terms of effectiveness of the intervention F=15.19(2, 57), p < .001. The MRI technologist felt that these interventions were helpful to the participants in keeping them calm and they did not disrupt the workflow or increase or decrease the length of the scan. Multilevel Modeling analysis revealed that the foot massage intervention had a significant contribution in the model (β= -1.35, SE=.63, p < 0.01). Effect of the touch intervention was not significant. Conclusion: The use of foot massage or touch is feasible in the MRI setting. Patients' comments indicate acceptability of an integrative approach to interventions.
  • AdaptiSPECT: a Preclinical Imaging System

    Chaix, Cécile (The University of Arizona., 2015)
    This dissertation addresses the design, development, calibration and performance evaluation of a pre-clinical imaging system called AdaptiSPECT. Single-Photon Emission Computed Tomography (SPECT) systems are powerful tools for multiple applications in small-animal research, ranging from drug discovery to fundamental biology. Traditionally, pinhole SPECT systems are designed with fixed imaging characteristics in terms of sensitivity, resolution and size of the field of view, that are dictated by the hardware configuration of the system. The SPECT system described in this dissertation can change its hardware configuration in response to the subject data it is acquiring in order to improve the imaging performance. We employed 16 modular gamma-ray detectors, each of which consists of a NaI:Tl scintillation crystal, a fused silica lightguide, and an array of 9 PMTs. The camera is designed to work with maximum-likelihood position estimation methods. These detectors are arranged into 2 rings of 8 detectors around an adjustable pinhole aperture. The aperture itself comprises three cylinders of different diameters, each with pinholes of different diameters. The three aperture cylinders are stacked together along the imager axis, and selection of the appropriate ring of pinholes is carried out by translating the entire aperture assembly. In addition, some sections of the aperture are fitted with shutters to open or close additional pinholes that increase sensitivity. We reviewed the method used to calibrate AdaptiSPECT, and proposed a new interpolation scheme specific to adaptive SPECT imaging systems where the detectors can move to multiple locations, that yields system matrices for any configuration employed during adaptive imaging. We evaluated the performances of AdaptiSPECT for various configurations. The magnification of the system ranges from 1.2 to 11.1. The corresponding resolution ranges from 3.2 mm to 0.6 mm, and the corresponding transaxial field-of-view ranges from 84 mm to 10 mm. The sensitivity of the system varies from 220 cps/MBq to 340 cps/MBq for various configurations. Imaging of a mouse injected with a bone radiotracer revealed the finer structures that can be acquired at higher magnifications, and illustrated the ability to conveniently image with a variety of magnifications during the same study. In summary, we have brought the concept of an adaptive SPECT imaging system as it was originally described by Barrett et al. in 2008 to life. We have engineered a system that can switch configurations with speed, precision, and repeatability suitable to carry out adaptive imaging studies on small animals, thus opening the door to a new research and medical imaging paradigm in which the imager hardware is adjusted on the fly to maximize task-performance for a specific patient, not, as currently, an ensemble of patients.

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