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The UA Dissertations Collection provides open access to dissertations produced at the University of Arizona, including dissertations submitted online from 2005-present, and dissertations from 1924-2006 that were digitized from paper and microfilm holdings.

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### Recent Submissions

• #### Secure Motion Claim Verification and Decision-Making for Vehicular Cyber-Physical Systems

Vehicular cyber-physical systems (CPSes) that integrate sensing, computing, control, and communication, together into various connected physical objects or infrastructures, have received significant interest in recent years. In a vehicular CPS, participating autonomous vehicles (AVs), which can be ground, aerial, or even marine, depend on reliable and secure vehicle-to-everything (V2X) communications to exchange useful information such as motion states (including positions, velocity, and acceleration), traffic conditions and road emergencies, etc. Acknowledging the correct V2X information can help system participants be aware of the environment and take proper action such as accelerating, brakes, or changing lanes, in order to enhance system safety, efficiency, as well as reduce energy cost. On the other hand, attackers have put numerous attention to contaminating the V2X communication for malicious purposes. Active malicious attackers may delay the V2X messages, or even spread messages containing false motion state information via V2X communication. For example, if one malicious vehicle claims accelerating but in fact slowing down, and meanwhile its following vehicle believes this claim, a severe collision may occur. However, traditional crypto-primitives can only guarantee the authenticity and integrity of these messages, but not the information truthfulness since attackers can modify it at the source. Also, stealthy attackers can send silent aerial vehicles (i.e. drones do not transmit anything.) to break the drone geofencing, aiming at illegally recording sensitive information. Thus, being able to securely verify motion states as well as determine the optimal response is of crucial importance in vehicular CPSes. Previous works that focus on locating/tracking AVs, either require sophisticated onboard hardware such as radar, lidar, and camera, or rely on centralized infrastructure (e.g. roadside units (RSUs)) to collect trustworthy information from honest neighbors. However, onboard sensors are usually very expensive. Honest neighbors as well as deploying RSUs for every local CPS cannot always be assumed. In this dissertation, we focus on developing a series of cost-effective secure schemes that achieves motion state verification, vehicle localization, tracking, and on-road decision-making, without the help of RSUs, expensive sensors, and honest neighbors, in a timely manner. We first motivate our research by introducing a message delay attack on the V2X communication channel. Then we propose a secure motion verification scheme for ground vehicles by utilizing the opportunistic reflection of the actively transmitted RF signal from vehicles. After that, an RF-based passive localization approach is proposed for a silent drone by exploiting the OFDM symbol properties in the signal reflection process. Fourthly, we propose a secure vehicle tracking scheme by examining the measurement residuals in an extended Kalman filter with the help of only one honest neighboring participant. Finally, a novel trust-aware decision-making framework based on utility-maximization and reinforcement learning is proposed, to help vehicles find the optimal action given the correct traffic information.
• #### Safe and Effective Opioid Prescribing Practices for Chronic Pain Patients

Background: Opioid addiction is a national crisis. A key factor of this crisis is the increasednumber of opioid prescriptions for chronic pain patients. The increased availability of opioid drugs has led to widespread misuse affecting millions of lives across the country. The devastating effects of prolonged opioid use have threatened public safety and have led to the need for a nationwide intervention. Despite the many factors contributing to the opioid crisis, new policies are needed to address educational gaps for chronic pain management, opioid prescribing practices, and opioid addiction. Purpose: This project aimed to determine if providing a brief educational session on evidence- based opioid prescribing practices for chronic pain patients will increase confidence in providers at an outpatient military clinic in Fort Sam Houston, Texas. Methods: This project used a quasi-experimental design with one group of participants. The KnowPain-12 survey questionnaire integrated with a 7-point Likert scale was used to anonymously measure each provider’s knowledge, attitude, and approach to managing chronic pain. All participants completed the KnowPain-12 survey questionnaire pre-intervention and post-intervention to measure knowledge gained. Results: There was an increase in total points for each participant after receiving the intervention. The most significant increase in points was noted with an eleven-point difference from pretest to posttest. Most of the responses favored the most appropriate choice, “Strongly Agree” or “Agree” for questions 2, 4, 6, 7, 8, 9, 12 and “Strongly Disagree” or “Disagree” for questions 1, 5, 10, and 11. Conclusion: This quality improvement (QI) project endeavored to provide an educational intervention to help providers appropriately prescribe opioids and manage chronic pain patients. There were positive results from the responses from the pre-intervention scores to the post- intervention scores. In addition, this QI project indicated that providing a well-rounded educational brief of evidence-based practices increased providers’ confidence of safe opioid prescribing to chronic pain patients.
• #### Increasing Provider Knowledge of Mental Health Apps

Purpose: The purpose of this quality improvement project was to educate psychiatric providers on mental health apps and improve competency in app evaluation. Background: Mental health apps offer the potential to increase access to care and improve health outcomes. Apps are especially promising for rural residents who face barriers to care and are more likely to die by suicide than their urban counterparts. While there are thousands of mental health apps available, the quality of apps varies dramatically. Some apps may contain harmful information, and others compromise patient privacy. Psychiatric providers need to know how to evaluate apps. Methods: A 20-minute training session was conducted targeting psychiatric providers in Northern Arizona. Attendees were provided education on mental health apps, in particular suicide prevention apps. A patient-centered teaching tool, developed by the primary investigator, was used to teach critical elements of app evaluation. After the training, attendees completed a survey to measure the success of the training. Results: Thirty-eight people attended the training. Of those, 13 consented to participate, including nine nurse practitioners, two physicians, and two non-clinical employees. Most participants work predominantly in outpatient behavioral health settings with patients who reside in rural areas. Participants reported that their knowledge of mental health apps increased after the training (p = 0.00338), and their comfort in app evaluation improved (p = 0.00512). An overarching theme emerged from participants’ responses to questions regarding the risks and benefits of mental health app use, which was safety. Participants stated that they plan to apply the knowledge gained during the training to their clinical practice. Conclusions: In an increasingly digital world, clinicians must know how to discern quality apps. This quality improvement project achieved all of the primary objectives. It also demonstrated that a patient-centered framework and teaching tool can successfully increase provider comfort in app evaluation. Future studies are needed to determine whether these initial positive findings are generalizable.
• #### Impact of a Brief Mindfulness Exercise on Practical Nursing Students’ Test Anxiety

Purpose: The purpose of this Doctor of Nursing Practice (DNP) project is to determine whether a brief, virtually delivered mindfulness-based intervention has an impact on the self-perceived levels of test anxiety in practical nursing students at GateWay community college in Phoenix, Arizona.Background: There is evidence in the current literature to support the use of a mindfulness exercise to alleviate stress and anxiety in students at varying levels of education. Nursing students face additional academic and testing stress which makes. The problem of test anxiety was identified and explored within practical nursing students. Methods: This quality improvement project used the Plan-Do-Study-Act cycle to implement a quasi-experimental pretest and posttest design intervention. First, the student’s baseline self-perceived test anxiety score was determined using a validated test anxiety scale. Secondly, a brief, virtual, mindfulness exercise was performed. Thirdly the test anxiety scale was administered again to determine if a change in self-perceived test anxiety levels occurred. Results: The pretest and posttest self-perceived test anxiety scale scores (n=14) were compared. The average pretest scores were 2.79, which are considered the high end of normal test anxiety. After the intervention the average score was 2.59 which is average test anxiety. Conclusions: The pretest and posttest comparisons demonstrated that a brief, virtually delivered mindfulness exercise reduced the self-perceived test anxiety scores of practical nursing students at GateWay community College in Phoenix, Arizona. This finding supports future exploration of how mindfulness can benefit nursing students.

• #### Experiences of Reproductive Health Among Transgender Men Following Surgical Gender Affirmation

Genital reconstruction is a hallmark gender affirmation procedure for a distinct subset of transgender men that require physical congruence with their expressed gender identity. Those that proceed with genital reconstruction are faced with a particularly finite set of decisions related to their physical body and emotional well-being, including the concession of their child-bearing potential. Current literature lacks a focus on the long-term implications of such outcomes, as well as an emphasis on fertility, biological parentage and non-infectious reproductive health concerns. The complex personal impact of dramatic gender affirming procedures remains an extraordinarily unmet need and was the focus of this research. The purpose of this study was to explore the experiences of reproductive health among child-bearing aged transgender men who underwent sterilizing genital reconstruction as a critical step in their gender affirmation journeys. A qualitative descriptive methodology, rooted in a complex adaptive systems (CAS) framework, allowed the principal investigator (PI) to support an environment of open dialogue to capture the holism of participants’ stories which could otherwise be deprioritized in pursuit of a linear and deterministic approach to data collection. Ten participants were recruited through social media and a leading reconstructive surgical practice for transgender persons. Each participant completed semi-structured, one-on-one interviews using videoconferencing and demographic questionnaires. Inductive data analysis, including affective coding, revealed thematic and categorical relationships which added a deeper emotional dimension to the subjective coding techniques. Six overarching themes of Gender Experience, Gender Affirmation, Fertility Concerns, Emotional Experiences, Health Care Provider Interactions and Communication were found. In addition to informing the narrative about the patterns and beliefs about fertility preservation, this study also expressed additional subcategory findings including self-acceptance, discovering one’s gender identity, and the complex impact of health care provider (HCP) interactions on this phenomenon of interest. These findings underscored the vital interdependency of research and practice and highlight opportunities for real-time advancements, as well as future endeavors to advance science and the standard of care for transgender patients.
• #### Parameter Characterization For Coating Thermo-Optic Noise and Coating Brownian Noise in Optical Cavities with Emphasis On Crystalline AIGaAs/GaAs Coatings

In this dissertation I describe methods for measuring material properties required for estimating noise in optical cavities from multi-layered optical coatings. This thesis is in two parts: The first part of the thesis describes an enhanced ringdown technique to test for amplitude-dependence of the mechanical loss in optical coatings. Ringdown methods for estimating the coating Brownian noise in a cavity rely on the the assumption that the loss is independent of oscillation amplitude. This allows experiments to artificially excite mechanical modes to amplitudes that are measurable by non-cavity means, such as optical levers and birefringence-based readouts. Here I describe the use of a GeNS system, read out by a low-noise Michelson interferometer to measure the amplitude dependence of loss in GaAs/Al$_{0.92}$Ga$_{0.08}$As multi-layer optical coatings on silica substrates in the range from just above the \textit{rms} thermal noise amplitude up to amplitudes typical of ringdown measurements: $10^{-1}-10^3$~picometers. These measurements set an upper limit on the amplitude dependence. I compare three crystalline coatings with varying levels of damage to determine if delaminated areas or other damage contributes to amplitude dependence. I compare the measured loss to a loss model consisting of coating thermo-elastic loss, coating bulk loss, coating shear loss, surface loss, substrate loss, edge loss and excess loss. I show that these measurements are limited by thermo-elastic and other losses associated primarily with bulk (volume-changing) coating deformations. The second part of this thesis describes methods for characterizing thermo-optic noise in single- and multi-layer coatings. I demonstrate that by measuring the wavelength shift with temperature, $\frac{\mr{d}\lambda}{\mr{d}T}$, of transmission spectra for single-layer coatings, we obtain a linear combination of $\alpha$ and $\beta$, the thermal expansion and thermo-optic coefficients of the coating. If the thermal expansion coefficient, $\alpha$, is already known, then our measurement gives $\beta$. I also demonstrate that by measuring $\frac{\mr{d}\lambda}{\mr{d}T}$ for multi-layer, high-reflectivity mirrors of the same type as in a cavity, we can calculate the cavity thermo-optic noise directly without the intermediate step of finding $\alpha$ and $\beta$ for the high and low index layer types respectively. We still need an estimate of the total coating thermal expansion coefficient $\alpha_c$, but the number of parameters needed is now reduced to 2, from 4 required previously. Finally, I show that by using lasers to measure the transmission changes on the band-edge of a high-reflectivity coating, we can get higher precision measurements but at the cost of reduced systematic accuracy.
• #### Profiling False ECG Crisis Alarms and Potential Causes

Background: The Joint Commission determines that clinical alarm systems are one of the highest patient safety issues. The Emergency Care Research Institute (ECRI) lists alarm overload as the 6th of the top 10 health technology hazards seen in healthcare technology-related issues. Despite the American Heart Association (AHA) recommendations for continuous Electrocardiographic (ECG) monitoring of hospitalized patients for heart rate and rhythm determination to diagnose arrhythmias, false arrhythmia alarms remain an issue for monitoring patients in the intensive care unit. Purpose: The purpose of this Doctoral of Nursing Practice (DNP) project was to determine the frequency, accuracy, and potential causes of false ECG crisis alarms. Methods: A retrospective quantitative descriptive study was conducted from an alarm database on a 12-bed adult intensive care unit within a hospital in the Southwest region of the United States. Results: The majority (95%) of crisis alarms in the intensive care units are false. The study showed high inter-rater reliability in false alarm determination. Out of 471 ECGs reviewed, 22 ECG alarms were true, two ECG alarms were undetermined, and 446 ECG alarms were false. The main non mutually exclusive causes of false alarms were artifacts (n=418, 93.7%), followed by low ECG amplitude (n = 264, 59.2%). Conclusion: The result of the project showed a high rate of false crisis alarms in the intensive care units. The findings of this project identified a need to develop quality alarm initiatives to decrease false ECG alarms and clinical alarm fatigue. This DNP project focused on evidence-based practice initiatives to address false crisis alarms.
• #### Critical Transcultural Competence Through Virtual Reality: Connecting Theories, Materials, and Practices

Despite growing interest in the cultural dimension of foreign language learning, the integration of culture and the promotion of intercultural competence into foreign language instruction are still not a priority for a majority of educators due to diverse reasons including demanding teaching duties, an already dense curriculum, and a lack of training. Additionally, in their classroom practices many educators are still relying on a definition of culture that does not reflect practical guidelines and curricular approaches set by scholars and professional organizations, perhaps because of outdated teaching resources. This suggests the need for teaching materials and professional development opportunities that enable educators to explore and experiment with new pedagogical resources that can promote a more updated conceptualization of culture. This three-article dissertation contributes to the existing scholarship on the teaching of culture in foreign language learning by proposing a novel framework for the teaching and learning of culture and by explaining how cutting-edge virtual reality materials can be used to promote culture from a critical and transcultural perspective. Data sources for this study included a nationwide survey with 197 participants, semi-structured interviews with 10 foreign language educators, and an eight-week online training and focus group interviews with seven foreign language educators of Italian. Article one explored US collegiate foreign language educators’ beliefs, practices, and the tools they use inside the classroom for the teaching and learning of culture. Article two proposed the “Critical Transcultural Competence” framework to support educators in the teaching of culture beyond essentialist views and limited intercultural perspectives and illustrated its application to virtual reality resources. Finally, article three is a mixed-methods case study investigating the development of pedagogical content knowledge regarding the proposed framework and its implementation in a lesson plan within a small group of collegiate Italian language instructors through a targeted online training. Altogether, the findings from the three articles suggest that although foreign language educators agree with the importance of exposing students to culture from a critical, not superficial, perspective, when looking at concrete classroom practices not enough time is devoted to culture to engage students in conversations that may lead to deeper understandings. The novel Critical Transcultural Competence framework, aimed at simplifying complex concepts by offering a set of principles for teaching and learning culture from a critical and transcultural perspective, proved useful in the online training. Nevertheless, some discrepancies were still noted between what educators believed and what they concretely did when putting their beliefs into practice in a lesson plan.
• #### Promoting Patient Safety During Intranasal Esketamine Administration

Purpose: Strengthen La Frontera psychiatric provider and nursing staff knowledge regarding intranasal esketamine therapy, promote safety of intranasal eskatamine administration at La Frontera, and increase intent to use a formal safety protocol during administration and patient monitoring. Background: Treatment-resistant depression affects nearly one-third of individuals diagnosed with major depressive disorder. Intranasal esketamine therapy is a new treatment available for individuals with treatment-resistant depression, and carries a significant risk profile, requiring administration and monitoring at designated clinics authorized to prescribe it. Presently, no standardized safety protocol exists to monitor patients during esketamine therapy sessions. Methods: This was a quality improvement project. The invited participants were 13 psychiatric providers and registered nurses at La Frontera in Phoenix, Arizona. The project design was an asynchronous educational PowerPoint presentation with pre- and post-presentation surveys delivered through Qualtrics via emailed hyperlink. Participation was voluntary and anonymous. Results: One invitee (n=1) participated in the intervention and submitted completed surveys. The sole participant indicated in their survey responses that their knowledge of intranasal esketamine therapy was enhanced. They further indicated a strong intent to use the proposed safety protocol were it to be implemented by La Frontera. 10 Conclusions: While the survey results indicate the participants’ knowledge of intranasal esketamine and intent to use a safety protocol was enhanced by the educational presentation, the small number of participants (n=1) made it very difficult to extrapolate any meaningful data regarding whether or not psychiatric providers and nurses at La Frontera found the educational presentation useful or informative, or whether a general sentiment in favor of adopting the safety protocol exists among La Frontera staff. This project provides an initial foundation for future research regarding the adoption of a standardized safety protocol among outpatient clinics administering intranasal esketamine. Further inquiries could help identify and overcome potential barriers, including alternative implementation strategies as well as modifications to the safety protocol to promote brevity.
• #### Controls on Land-Air Carbon and Water Exchange in Semiarid Ecosystems

Warming and rainfall intensification linked to climate change will alter water availability in drylands—arid and semiarid regions that cover 41% of the land surface, house over two billion people, and impact global carbon and water cycling. In these water-limited systems, episodic rainfall drives pulses of plant and soil activity that regulate ecosystem exchanges of water and carbon. Despite the outsize importance of pulse events on dryland carbon and water dynamics, prior frameworks have not considered how rising atmospheric demand and the intensification of rainfall modify pulse responses. Moreover, models of soil carbon emissions are largely based on studies from temperature-limited, mesic regions which may not reflect how soil moisture regulates respiration processes. These knowledge gaps limit our ability to assess how changing moisture availability in a warming climate will impact dryland carbon and water cycling. My dissertation addresses these gaps by using observations to confront models and advance the pulse framework of water-limited ecosystems. In Appendix A, I identify the dominant drivers of soil CO2 efflux in drylands and present a model that can capture efflux dynamics by considering interactions among temperature, moisture, and photosynthesis. In Appendix B, I integrate flux tower datasets to show that high atmospheric demand suppresses ecosystem photosynthesis more than respiration or evapotranspiration, which decreases the carbon uptake and water efficiency of rain pulses. In Appendix C, I use a rainfall manipulation experiment to conclude that precipitation intensification toward fewer, larger storms decreases seasonal soil CO2 efflux in a semiarid grassland. Together, these findings advance the pulse paradigm and indicate the potential for climate-mediated shifts in dryland carbon and water cycling.

• #### Targeting the Central Dogma to Inhibit Nodes of Convergence in Cancer

Cancer treatments often target singular oncoproteins in attempt to block one hallmark of cancer and stop tumor growth and progression. However, although these treatments are often initially effective, many cancer patients develop resistance and experience relapse due to redundant signaling or tumor heterogeneity. To avoid resistance mechanisms, cancer treatments must inhibit multiple hallmarks of cancer, and therefore multiple oncogenic signaling programs. One possible way to achieve this is to target nodes of convergence of oncogenic signaling, in which multiple oncogenic pathways depend on one protein for expression or signal proliferation. These nodes can be found within the central dogma processes that drive all cellular function. In this dissertation, this strategy is used to discover inhibitors of nodes involved in transcription, translation, and protein folding of oncogenes and oncoproteins. Targeting nodes of convergence may yield inhibitors that evade resistance mechanisms that plague current cancer therapies and provide superior clinical outcomes for cancer patients.
• #### Structure-Function Relationships and Advanced Data Analysis in Single Molecule Quantum Transport

Incorporating individual small organic molecules into electronic circuits has the potential to enable smaller and more efficient devices, while also providing an excellent experimental platform for investigating the fundamental physics and chemistry of quantum transport. Key to advancing both of these goals is the continued development of structure-function relationships that predictively connect molecular design to observed transport behavior. Despite their apparent simplicity, single-molecule systems often display complex interactions between different physical effects, and so structure-function relationships that account for these interconnections are an especially important, and relatively understudied, need for the field. A second major challenge for single-molecule transport research is that modern experimental platforms tend to produce large, stochastic, and high-dimensional datasets. Methods to robustly extract meaningful information from such datasets are thus required to fully probe the range of behaviors occurring in single-molecule circuits, and to understand how those behaviors relate back to molecular design. In this dissertation, I describe contributions to help address the need for both nuanced structure-function relationships and sophisticated data analysis strategies for single-molecule quantum transport research. The experimental platform I used to measure single-molecule charge transport is described in detail, along with the type of data it collects and the subtleties of how those data are processed. Motivated by those details, I describe my overall approach to analyzing single-molecule data and then introduce, validate, and utilize novel machine learning algorithms that I developed to address specific challenges. These include a novel segment clustering algorithm for reliably extracting molecular features and an original correlation-based framework for identifying meaningful rare events. Using some of these new tools, I then report single-molecule conductance measurements for two series of molecules that reveal previously unknown connections between different physical effects in metal/single-molecule/metal junctions. The first study focuses on energy-level alignment between the bridging molecule and the metal electrodes, and finds that linked effects determine the tunability of conductance for molecules with varying chemical substituents. Finally, in the second study I demonstrate how backbone conformation and metal/molecule electronic coupling, which are often approximated as independent, can in fact be strongly correlated in the case of fairly common structural components. Together, all of these advances in the collection, analysis, and interpretation of single-molecule transport data help to deepen our understanding of physical chemistry in nanoscopic systems.
• #### Symphony No. 2

Symphony No. 2 is an experiment in romanticism. The work is a composition in four movements, exploring orchestration, formal elements, styles of the 21st century inspired by those traditions of the classical and romantic periods, and thematic metamorphosis – the primary underpinning of the work. The duration of the composition is roughly 26 minutes, and it is written for a standard-sized orchestra.
• #### Characterization and Modeling of Deformable Mirrors for Extreme Adaptive Optics

In the next decade, multiple extremely large telescopes (ELTs) with the capability to directly image earth-like planets around other stars will begin operations. These planets are much fainter than their host stars, and successful detection and characterization will require extreme adaptive optics (ExAO) systems capable of creating and maintaining extremely high contrast regions in the focal plane (dark holes), in spite of atmospheric turbulence. To perform the wavefront correction needed to dig these dark holes, these systems will rely on deformable mirrors (DMs) with >10,000 actuators run at several kHz. The calibration and optimization of these DMs will be a key challenge to overcome to maximize the performance of these instruments. In this dissertation, we report the characterization of microelectromechanical systems (MEMS) and compact voice coil DMs for MagAO-X, a new ExAO system for the 6.5 m Magellan Clay telescope in Chile and pathfinder for the future Giant Magellan Telescope (GMT) ExAO instrument. We implement a number of focal-plane wavefront control strategies that use these integrated DMs to optimize the MagAO-X wavefront for high contrast imaging. Finally, we develop a model to capture the dynamics of the DM facesheet, employ estimation techniques to calibrate it against a MagAO-X DM, and integrate it with an AO simulation to assess the impact of DM dynamics on AO performance.
• #### Signal Processing of Seismic and Image Data for Planetary Exploration

The field of Earth and planetary sciences seeks to clarify the physical processes and properties of Solar System bodies and their surrounding space environments. Robotic space missions launched from Earth have been pivotal for advancing this knowledge. On Earth, planetary analog studies can also address the feasibility of Solar System investigations with significantly less complexity and cost. Here, I explore data acquired from spacecraft and planetary analog studies that examine wave phenomena from seismic and light sources. Specifically, I use these data to establish the properties of hydrated planetary bodies. The first part of this dissertation demonstrates how seismic events from Earth’s cryosphere provide an analog for the signals anticipated from a future mission to an icy moon (Appendices A-B). In particular, I examine data from terrestrial analogs of Jupiter’s satellite Europa, which bears a frozen crust, subsurface ocean, and represents a potentially habitable environment in the outer Solar System. I process high-frequency and broadband seismograms from the Greenland ice sheet to explore techniques that will maximize the scientific yield of a Europa Lander seismometer, an instrument concept currently under study by the National Aeronautics and Space Administration (NASA). In the last section (Appendix C), I investigate color images of asteroid Bennu acquired by NASA’s Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx). Bennu is a hydrated and carbon-bearing primitive asteroid and may be similar to the objects that delivered water to the early Earth. In each of these studies, I apply a standard toolbox of digital signal processing methods, which have broad utility when analyzing data returned by different instruments designed to sense distinct geophysical processes.
• #### Community Gardens and Neighborhood Safety: Enhancing Urban Spaces, Improving Health, and Reducing Crime Through Urban Agriculture

Background: Research has found that community garden participants consume more fruits and vegetables than nonparticipants and that gardens add beauty to neighborhoods and help participants generate social capital. Urban greenspaces have been associated with a variety of physical and psychosocial health benefits, from self-reported health to cardiovascular health. Research has repeatedly found that urban greenspace is associated with reductions in crime and increased perception of community safety, but few studies have assessed impacts of community gardens on crime rates. Objective: This project evaluated whether and how community gardens affect crime rates. Then, a theoretically grounded framework for communicating such findings to maximize impact and uptake among policymakers and practitioners is proposed. Methods: Aim I: To address questions raised by community representatives, I obtained crime data from the Tucson Police Department (TPD) for the years of 2009-2013. GIS data was later supplemented with primary data on garden cultivation status, collected from garden visits conducted in 2015. Eleven gardens observed to be under cultivation in 2015 were included in the analysis. This data was analyzed using differences-in-differences estimation to determine relative change in crime levels for neighborhoods into which gardens were introduced and adjacent areas. Aim II: To inform dissemination of findings for maximum impact on policy and practice, a theoretically grounded framework for dissemination is proposed. Aim III: The proposed framework for communicating research findings is pilot tested and to impact emerging practitioners’ approaches. Results: Aim I: Differences-in-differences estimation that that the installation of community gardens was associated with decreases in Total Crime, Motor Vehicle Theft, Assaults, Robbery, Sexual Assault, and Suspicious Activity. The installation of the gardens was associated with increases in Larceny, Narcotics, and Disorderly Conduct. Aim II: A policy brief and a lay journal article were then created in alignment with the framework to outreach to policy makers and practitioners of urban agriculture, respectively. Aim III: Two case studies are presented demonstrating how emerging practitioners applied these research findings to practice generating policy change relative to urban land use for community safety and vacant lot conversion, respectively. Conclusion: The introduction of community gardens was associated with decreases in violent crime rates, which is consistent with associations seen when other types of greenspace have been introduced into urban environments. These findings are important because they demonstrate the multi-pronged benefits of community gardens, yielding healthful foods, social capital and physical activity increases for gardeners, neighborhood beautification, and decreases in crime rates as well. These findings can be utilized to encourage policies that promote the practice of community gardening, or urban agriculture. Given disparities in access to greenspace, quality food environments, and exposure to crime, urban agriculture presents a promising approach to creating cross-cutting interventions to counteract health disparities.
• #### A Narrow Therapeutic Range: Public Health Role of Micronutrient Dietary Supplementation – Chronic Disease Prevention to Consumer Safety Risk

BACKGROUND: Micronutrients are essential chemical compounds required in small quantities by humans and other living organisms for tissue growth and development, immune function, disease prevention, and optimal health. Dietary supplements have recognized benefits for certain populations, such as folic acid and iodine for pregnant or lactating women, vitamin D for the elderly and persons who lack adequate sun exposure, and vitamin B12 for vegans. However, there is insufficient scientific evidence to justify their use for reasons other than pregnancy, lactation, or deficiency. There are also safety risks associated with micronutrient supplementation ranging from potential interaction with prescription drugs to toxicity from excessive use. This benefit-risk trade-off is further complicated by the economic value generated by dietary supplement manufacturing and sales in the United States, which exceeded \$46 Billion in 2020. OBJECTIVE: This dissertation examines the Janus-like quality of micronutrient dietary supplement use in three study manuscripts listed in the Appendix. They investigated three key research questions. Study 1: In the modified Sel/Cel Clinical Trial (“Modified Sel Trial”) conducted between 2001 and 2013, is the risk of colorectal adenoma recurrence in patients treated with selenium versus placebo meaningfully different when calculated on a per-protocol versus intention-to-treat basis? Study 2: For the Nurses’ Health Study II (NHSII) prospective cohort, was chromium, selenium, or zinc supplement intake associated with risk of incident endometriosis? Study 3: In the Quincy Biosciences v. Federal Trade Commission class action lawsuit settled in 2020, were Quincy Bioscience’s unplanned post hoc subgroup results for Prevagen®, a dietary supplement hereafter referred to as “Prevagen”, statistically significant versus placebo in a randomized clinical trial?
• #### Beyond Bed Nets: Exploring Household Malaria Prevention Methods and Health Outcomes in Western Kenya

Background: Malaria remains a leading cause of morbidity and mortality, especially among children, in sub-Saharan Africa. Globally, there were an estimated 229 million malaria cases in 2019. The World Health Organization (WHO) promotes integrated vector management to prevent malaria, which includes the use of long-lasting insecticide treated bed nets (LLINs), Indoor Residual Spraying (IRS), and environmental management. While LLINs and IRS have been shown to be highly effective in controlled conditions, there are still challenges with community acceptance and consistent use of these methods. People often implement multiple malaria prevention strategies and the choice of which strategies to use is influenced by myriad of individual, household, community, and global factors. The use of smoke-based malaria prevention methods, like mosquito coils, has been documented across sub-Saharan Africa. Several studies have documented the association between exposure to mosquito coils/burning biomass and respiratory illnesses, including acute lower respiratory infections (ALRIs), while other studies suggest they be protective against malaria. Methods: This study combined qualitative and quantitative methods to investigate the use of malaria prevention methods in two sites in western Kenya with disparate malaria transmission. In June 2015, focus groups on malaria prevention knowledge, attitudes, and practices were held with approximately 80 people across the two sites. Simultaneously, a cross-sectional study was conducted among 1,213 households in the same areas using cluster random sampling to 1) identify the types, frequency, and determinants of malaria prevention methods used and 2) identify the risk of acute lower respiratory infections (ALRI) and malaria in relation to smoke-based malaria prevention strategies. Results: Focus group participants perceived malaria as a serious issue, but they perceived benefits of mosquito control beyond malaria prevention (ex. having more comfortable sleep). Focus Group Discussions (FGD) and the household survey confirmed that households use multiple strategies, often concurrently, to control mosquitoes and to prevent malaria. While bed nets were the most frequently used malaria prevention method, nearly 20% of households used smoke-based prevention methods. The methods varied, however, significantly between the two sites. Households from the lowlands generally used more methods and more often than those in the highlands. In this study, prevalence of ALRI and malaria was 7.5% and 20.5%, respectively. ALRI was highest among adults aged 66 and older and children aged 2-4 years, and malaria was highest in children aged 5-11. The lowlands had significantly higher ALRI and malaria prevalence for all age groups. Exposure to high levels of smoke-based malaria prevention methods among children under 5 years was associated with 3.1 times the odds of ALRI compared to those with low exposure after controlling for other sources of smoke exposure. No significant association between smoke-based malaria prevention methods exposure and ALRI was found among individuals 5 years of age and older. Additionally, there was no association between the use of smoke-based malaria prevention methods and current malaria infection. Conclusions: The use of malaria prevention methods is driven by a myriad of individual, household, community, and sociocultural factors. Households use multiple methods of malaria prevention, often concurrently. While bed nets were reported to be widely used, people were also using potentially harmful methods to prevent malaria including burning biomass, mosquito coils, and man-made materials. Our study found an association between higher levels of smoke-based malaria prevention methods exposure and ALRI among children under 5 years. We found no association between current malaria infection and exposure to smoke-based malaria prevention methods, indicating the health risks of smoke-based methods may outweigh the benefits, especially among children. Removing smoke-based methods as a source of indoor air pollution (IAP) could help reduce overall risk for ALRI among young children, and the use of smoke-based prevention methods indoors should be explicitly discouraged due to the risk of respiratory illness.