The UA Master's Theses Collection provides open access to masters theses and reports produced at the University of Arizona, including theses submitted online from 2005-present and theses from 1895-2005 that were digitized from microfilm and print holdings, in addition to master's reports from the College of Architecture, Planning and Landscape Architecture from 1966 onwards. The collection includes hundreds of titles not available in ProQuest.

We have digitized the entire backfile of master's theses and doctoral dissertations that have been submitted to the University of Arizona Libraries - since 1895! If you can't find the item you want in the repository and would like to check its digitization status, please contact us.

The UA Master's Theses collection is not comprehensive; master's theses from 1993-2015 were only received and archived by the UA Library and ProQuest if the student chose to pay the optional archiving fee. The Library does not have copies of many master's theses submitted during this time period. Some academic departments may keep copies of theses submitted to their programs. Colleges and departments wishing to archive master's theses not available in the University Libraries are encouraged to contact us at repository@u.library.arizona.edu.


Please refer to the Dissertations and Theses in the UA Libraries guide for more details about UA Theses and Dissertations, and to find materials that are not available online. Email repository@u.library.arizona.edu with your questions about UA Theses and Dissertations.

Recent Submissions

  • Quantifying X-ray Diffraction Reconstruction Fidelity

    Luo, Bobing (The University of Arizona., 2022)
    With increasing transport security awareness and the demand for threat detection, X-ray diffraction (XRD) technology is developing continuously [1]. X-ray diffraction imaging refers to the method of using X-rays, namely beams with photon energy between 1keV to 150keV , to detect the scattered light from the interaction between objects with different materials and X-ray photons, to infer the type of material by measuring momentum transfer of photons. Unlike computed tomography (CT), X-ray diffraction not only provides the spatial distribution of objects, but also the molecular material composition. As such X-ray diffraction requires complex computations and a challenging measurement. A variety of XRD reconstruction algorithm have been developed, such as state-of-the-art Group Total Variation. The goal of this work is to quantify XRD reconstruction algorithm performance with respect to signal-to-noise ratio (SNR), material categories and collimation/coding schemes.
  • Conifer Resilience Following Wildfire and Drought in Southeastern Arizona Sky Islands

    Falk, Donald A.; Fule, Miles; Mcguire, Luke; Predick, Katie (The University of Arizona., 2022)
    Wildfire size, severity, and frequency have been increasing in the Southwestern US since the mid-1980s as a direct result of anthropogenic climate change and land management practices. Significantly, high severity burn area in Arizona and New Mexico has been increasing at a rate of about 1,000 ha per year since 1985. This increase in more frequent, higher severity wildfire, combined with two decades of drought, threatens the persistence, regeneration, and resilience of conifer trees in the dry pine forests of Southern Arizona’s sky islands. Failure of conifers to recover may result in ecosystem conversion, where forested areas are replaced by oak or shrub woodlands. Here we report on radial tree growth, conifer regeneration, and community composition in the Santa Catalina Mountains (SCM) following wildfires in 2002, 2003 and 2020. For our tree growth analysis, we found a striking resilience to both drought and wildfire in three dominant conifers. Pines that burned at high and low severity in particular showed non-significant positive growth trajectories following wildfire exposure in 2003. Douglas-fir growth was more climate-dependent and less fire-dependent than Pinus growth. For areas that burned only in the earlier fires, conifer regeneration over the 17–18-year interval was found in the majority of burned plots, although density varied greatly. Community composition analysis in these areas found some loss of conifer overstory dominance in areas burned at high severity; in general, these were replaced mainly by Aspen (Populus tremuloides) in higher elevation stands, not deciduous or evergreen oaks. Community composition analysis for areas that burned in the most recent fire showed wide variability and may be seen as a starting point for future trajectories of change in Southwestern forests under the influence of changing climate and fire regimes.
  • Mortality Thresholds of Juvenile Trees to Drought and Heatwaves: Implications for Forest Regeneration Across a Landscape Gradient

    Falk, Donald A.; Breshears, David D.; Lalor, Alexandra Rose; Loehman, Rachel A.; Triepke, Francis Jack (The University of Arizona., 2022)
    Tree loss is increasing rapidly due to drought- and heat- related mortality and intensifying fire activity. Consequently, the fate of many forests depends on the ability of juvenile trees to establish following exposure to heightened climate anomalies. Climate extremes, such as droughts and heatwaves, are increasing in frequency and severity, and tree survival in mountainous regions must contend with these landscape-level climate episodes. Recent research focuses on how mortality of individual tree species may be driven by drought and heatwaves, but how mortality from protracted drought and associated warming would vary among multiple species spanning an elevational gradient given concurrent variation in climate, ecohydrology, and physiology remains unclear. We address this question by implementing a growth chamber study, imposing extreme drought with and without a compounding heatwave, for five species that span elevations across a semiarid elevational gradient in the southwestern United States. Overall, the length of a progressive drought required to trigger mortality differed by up to 20 weeks among species, whereas inclusion of a heatwave hastened mortality by about one week. Lower elevation species that grow in warmer ambient conditions died earlier (Pinus ponderosa in 10 weeks, Pinus edulis in 14 weeks) than did higher elevation species from cooler ambient conditions (Picea engelmannii and Pseudotsuga menziesii in 19 weeks, and Pinus flexilis in 30 weeks). When exposed to a heatwave atop drought, mortality advanced significantly only for species from cooler ambient conditions (Pinus flexilis: 2.7 weeks earlier; Pseudotsuga menziesii: 2.0 weeks earlier). Cooler ambient temperatures and associated differences in ecohydrology-related soil evaporation may have provided a buffer against moisture loss during drought, potentially overriding expected differences in drought tolerance due to tree physiology. Our study suggests that droughts will play a leading role in juvenile tree mortality and will most directly impact species at warmer climate thresholds, with heatwaves atop drought potentially exacerbating mortality especially of high elevation species. These responses are relevant for assessing the potential success of both natural and managed reforestation, as differential juvenile survival following episodic extreme events will determine future landscape-scale vegetation trajectories under changing climate.
  • Phenology of Lesser Long-Nosed Bats and their Food Plants

    Steidl, Robert J.; Arnold, A. Elizabeth; Walker, John-Lee S.; Prudic, Kathleen L. (The University of Arizona., 2022)
    Lesser long-nosed bats (Leptonycteris yerbabuenae) are important pollinators and seasonal residents along the U.S-Mexico border. Because they feed on flowering and fruiting plants, they are vulnerable to phenological shifts in those species. To evaluate synchrony between bats and their key food plants, we characterized seasonal abundance of bats and flowering and fruiting phenology of food plants at roosts in 2010, 2011, and 2021. Although phenology of bats and their food plants was generally consistent across years, we observed modest changes in aspects of flowering and fruiting of saguaro (Carnegiea gigantea) and organ pipe cacti (Stenocereus thurberi). At maternity roosts, bat abundance was synchronized more tightly with flowering phenology of saguaros in 2021 than in 2010-11. At post-maternity transient roosts, bat abundance was synchronized less tightly with flowering phenology of agaves (Agave palmeri) in 2021 than in 2010-11. We complemented these analyses by improving methods for non-invasive genetic sampling of this species. Specifically, we developed a two-step amplification approach to analyze microsatellite loci and identify individual bats via DNA extracted from fecal samples. As a proof of concept, five highly polymorphic microsatellite loci distinguished 434 individuals reliably. The probability of two closely related individuals having the same genotype at all five loci was 0.003, and the overall probability of identity was 7.5E-09. Addition of a multiplex step added minimal cost, improved amplification success, and conserved DNA extracts. Repeated analyses showed genotyping error was <2%. We explore the benefits and limits of our approaches for population studies of lesser long-nosed bats and other species that provide key ecosystem services and are commonly of conservation concern.
  • An Investigation of Acid Mist Formation and Suppression Mechanisms in Copper EW Plants

    Zhang, Jinhong; Roa, Therese; Tenorio, Victor; Waqas, Muhammad; Heath, Gail (The University of Arizona., 2022)
    During the copper electrowinning (EW) process, oxygen gas is produced on the anode and forms bubbles which rise to the surface bursting at the air/solution interface. Acid mist is released and negatively impacts workers’ health while also corroding equipment and tank house surroundings. Although there are several ways of reducing acid mist, adding anti-mist agents is the most economical method currently in use to suppress acid mist. However, the search for an environmentally friendly mist suppressant is greatly hindered by the fact that the acid mist formation as well as suppression mechanism is not fully understood. In the present research, the physical-chemical properties of the electrolyte (density, surface tension, viscosity) are characterized, particularly the effects of changing temperature and surfactant concentration. A High-Speed Video Camera (HSVC) is utilized to study the bubbles’ burst/rupture process at the solution/air interface at varying bubble diameters. The findings not only hope to clarify the mechanisms of acid mist formation and suppression but additionally help with the search for and application of an environmentally friendly anti-mist agent for copper electrowinning.
  • Coahuilteco Language Reclamation Program

    Silva, Wilson De Lima DL; Acosta, Miguel R.; Zepeda, Odelia; Harley, Heidi (The University of Arizona., 2022)
    The Coahuilteco language had been dormant for approximately 200 years. It was documented by two Franciscan priests, Gabriel De Vegara (1730) Cuadernillo de los Indios Pajalates and Bartholomé Garcia (1760). Manual para administrator los santos sacraments de penitencia, eucharistia, extrema-uncion, y matimonio: dar gracias despues de comulgar y ayudar a bien morir. These documents represent the limited corpus of the language. These documents were analyzed and described by two American linguists John Reed Swanton (1940) and Rudolph C. Troike (1959-2015). Their analyses and descriptions of the language posed many problems (reading and interpreting linguistic jargon) for the community of lineal descendants attempting to awaken and reclaim the language. Troike (p.c.2016) provided the community with valuable insights and decoding keys to help the community interpret the linguistic jargon; thus, helping the community answer the question of ‘‘How do we facilitate the teaching and learning of the scholarly research of the heritage language to the community?” Further knowledge of teaching the scholarly material has been provided by Wilson De Lima Silva (p.c.2022).
  • Clínica Integral Almas: Tackling the Social Determinants of Health while Cultivating a Community of Care in Rural Guarijío-Makurawe Communities of Sonora, México

    Graeter, Stefanie; Resendiz , Dasy Jazmin; Cordova-Marks, Felina; Rivera Cohen, Aracely; Vasquez-Leon, Marcela (The University of Arizona., 2022)
    The Mexican health system is fragmented into sub-systems and levels of care, including private and public services, which create inequalities in access and quality of services and treatment in rural and Indigenous communities. In addition, the COVID-19 pandemic has exacerbated the lack of medical and healthcare services (Gomez, 2011 and Doubova et al., 2022). This project aimed to explore how Clínica Integral Almas (CIA), a rural Sonoran non-profit clinic run by a team of Mexican healthcare providers, has addressed the social determinants of health, and has provided services to Guarijío-Makurawe communities of thirteen villages and surrounding municipalities in Álamos. Over the course of two months, eighteen semi-structured interviews and multiple field observations were conducted with Mexican physicians (n=4), patients (n=5), Clínica Integral Almas staff (n=2), community health workers (n=4), and U.S and Mexican healthcare workers (n=3). Patients and community health workers included Guarijío-Makurawe individuals, an Indigenous group from north-central México. Patients, doctors, and staff included Álamos non-Guarijío-Makurawe participants. Lastly, healthcare workers included participants from México and the US. With non-governmental medical healthcare resources and expertise, the cultivation of care, accompaniment, and the use of traditional medicine, Clínica Integral Almas (CIA) physicians and community health workers have been able to address, many of the social determinants of health that can lead to negative health outcomes in rural communities of Álamos, Sonora, México.
  • Dance Education in the US: What is Known about the Field, and How Do We Go About Improving It?

    Smith, Eric D.; Liu, Yao; Burross, Heidi Legg; Pope, Elizabeth J. (The University of Arizona., 2023)
    Dance education seeks to develop students’ dance abilities and performance through effective pedagogical techniques. This literature review examines the current status of K-12 dance education in the United States, including the development of dance education, the importance of dance education, current problems in American dance education, and current solutions to the problems. Through the review of these areas, three factors in dance education take principal focus: curriculum, teaching methods, and assessment. Based on prior research, I propose a model to examine the relationships between these three factors in an effort to holistically improve dance education and offer suggestions on how to test the proposed model.
  • Clinical Implications of Community Attitudes and Beliefs about Sleep: An Examination of Excessive Daytime Sleepiness and Fatigue

    Grandner, Michael; Featherston, Breanna; Fox, Rina S.; Fernandez, Fabian (The University of Arizona., 2022)
    Background: Excessive daytime sleepiness (EDS) and severe fatigue are two widely prevalent, yet undervalued and undertreated clinical conditions. The disparity in their treatment is surprising given their respective multidimensional physiological effects. This may be explained due to the known effects that public attitudes and beliefs can have on utilizing healthcare. Therefore, this study aims to analyze if one’s beliefs and attitudes about sleep and sleep treatment impact one’s own sleep health, or vice versa.Methods: N = 28 participants presenting with excessive daytime sleepiness (ESS ≥ 10) were recruited from the community. Participants were administered an Epworth Sleepiness Scale and Fatigue Severity Scale at baseline, as well as a survey about a wide range of beliefs and attitudes about both common strategies to ameliorate daytime sleepiness, as well as seeking medical care about sleepiness. Participants reported whether they Strongly Agree (SA), Agree (A), Disagree (D), or Strongly Disagree (SD) with each respective statement. Ordinal logistic regressions examined agreement associated with baseline sleepiness and fatigue, adjusted for age, sex, and race/ethnicity. Nominal significance was determined as p<0.05. Results: Individuals with higher levels of baseline daytime sleepiness were more likely to agree that taking medication (both prescription and/or over-the-counter), napping, and “power[ing] through” are good strategies to alleviate sleepiness symptoms during the day. However, only higher fatigue severity was associated with the endorsement of statements relating to seeking treatment, particularly that they already have spoken with a clinician about their symptoms. Conclusions: Some beliefs and attitudes about sleep were correlated with higher levels of daytime sleepiness and fatigue, especially those related to “powering through” daytime sleepiness and advocacy for medication. Similarly, there is a discrepancy in seeking treatment for sleep problems between those with high EDS levels versus those with high fatigue levels. Therefore, attitudes and beliefs, and possibly presence of respective conditions/symptoms, can potentially affect treatment utilization and/or efficacy. This fact confirms the importance for clinicians and researchers to pay attention to their own patient’s attitudes and beliefs about health. This also emphasizes the need for an increase in public health education about sleep and sleep health.
  • Combination of Immune Checkpoint Inhibitors in Urothelial Carcinoma: PD-1/PD-L1 and CTLA-4

    Zavros, Yana; Chipollini, Juan; Ogbuji, Chizitaram Vanessa; Lybarger, Lonnie; Recio-Boiles, Alejandro; Mochel, Jonathan (The University of Arizona., 2022)
    Urothelial carcinoma is the most common form of bladder cancer and is the variant with the most immunogenic response. This makes urothelial carcinoma an appropriate candidate for immunotherapy in the form of immune checkpoint inhibitors. Immune checkpoint inhibitors are antibodies directed against immune checkpoint-related molecules expressed on tumor-infiltrating lymphocytes. There have been multiple studies on the role of the immune checkpoint molecule, PD-1 on T-cells and its interaction with the ligand PD-L1. Moreover, CTLA-4 is a different checkpoint also expressed on T-cells in urothelial carcinoma. The blockade of CTLA4 can lead to the reactivation of lymphocytes by preventing apoptosis and anergy. The only FDA-Approved immune checkpoint inhibitors for metastatic urothelial carcinoma target the PD-1/PD-L1 pathway. However, the overall response rate and progression-free survival rates of these drugs are not sufficient in the patient population. In this review, the current immune checkpoint inhibition (ICI) treatment landscape is explored with an emphasis on combination therapy in the form of PD-1/PD-L1 with CTLA-4. Investigation of the current literature on ICI in in-vivo experiments shows a decrease in tumor volumes and size when PD-1/PD-L1 is blocked, and this result is replicated in CTLA-4 blockade. However, there are limited preclinical models testing tumor response in combination blockade of CTLA-4 in the presence of PD-1/PD-L1 blockade. In this review, a proposal on canine organoid bladder samples as a complement to transgenic mice for preclinical drug testing is also explored. We anticipate this review to be a foundation for a deeper experimental investigation into combination therapy in the form of PD-1/PD-L1 and CTLA-4 blockade in metastatic urothelial carcinoma.
  • Non-Invasive Hand Free Control of a Robotic Arm

    Fuglevand, Andrew; Gin, Derek Martin; Eggers, Erika; Toosizadeh, Nima (The University of Arizona., 2022)
    Thousands of spinal injuries occur every year, resulting in total or partial quadriplegia. This debilitation robs people of their autonomy, in addition to the large financial cost of care and lost work. Some devices to return some autonomy exist, however, most of them require some movement or involve pre-programmed actions for a set environment. This experimental study seeks to design and compare novel methods of controlling a robotic arm pointer to a baseline, hand-controlled, mode. The modalities compared include a heads-position using a motion sensor to directly map the tip of the robotic arm to the position of the head, head velocity to create a vector to control the direction and speed based on the position of the head, and voice control which causes the tip to move in a singular direction or stop based on specific vocal input. Head position was found to be similar to hand control, performing significantly better than head velocity and voice control when observing movement time to target and throughput. Path length saw no significant differences between baseline and the three experimental modalities, and the NASA TLX showed a noteworthy dislike for head velocity mode. While this study lacks any form of gripping mechanism, it lays the groundwork for head position mode to be a novel method of control, for individuals with partially or totally limited body movement.
  • Study of Bubble Size Distribution in Electrowinning of Copper and an Improvement in Acid Mist Suppression

    Zhang, Jinhong; Danishwar, Muhammad; Waqas, Muhammad; Tenorio, Victor (The University of Arizona., 2022)
    In the final step of the hydrometallurgical production procedures for metals like copper, zinc, and nickel, an acid mist is produced during the electrowinning process. On the anode during electrowinning, oxygen bubbles develop. Small acid-containing liquid droplets are created when these bubbles pop at the interface of the solution and the air, becoming airborne and spreading throughout the workplace. These "acid mist" droplets present a serious health risk to the workers. Additionally, it causes severe structural and equipment corrosion, which costs the sector millions of dollars annually. Little quantitative data on the production of acid mist and the factors influencing its amount was available prior to this study. Theoretical analysis of the origin of acid mist shows that, contrary to what is usually believed, the acid mist is almost entirely produced from airborne jet droplets. Jet drops are produced when a liquid jet that forms when the bubble cavity collapses disintegrate. Furthermore, despite the fact that it was widely known that the size of the electrolytically created bubbles was proportional to the amount of acid mist, no systematic measurements had been done to characterize bubble size and its correlation with material and process variables. The current study looks into the factors that determine the number of jet drops produced and bubble size. The relationship between the number of jet drops and bubble size and the mechanisms that cause the acid mist to form. For measuring the size of oxygen bubbles created on the anode during copper electrowinning, a method is developed. The bubbles are photographed in high resolution using a microscopic camera and extremely bright light source. Regardless of the operating conditions, it is discovered that bubbles are produced in a wide size distribution, with a mean diameter of cumulative 80% of the bubbles (P80) was 16 µm. The solution temperature was changed to determine its influence on bubble size. According to experimental data, the diameter of the jet drops produced during copper electrowinning can range from roughly 0.1 mm to 5 mm. Small plastic balls and beads that float are frequently employed in industry to suppress acid mist. Due to their greater buoyancy and greater coverage of the solution surface, spherical-shaped floating barriers minimize acid mist the most when compared to single-layered floating barriers. The lower density allows these to be more buoyant in the solution and more effectively intercept acid mist. Hydrophilic floating objects, on average, reduced the weight loss of bulk solution to about 83% and hydrophobic floating objects were only able to reduce the weight loss to 56% over the course of 60 minutes. The suppression of acid mist is significantly affected by the addition of hydrophilic floating coverage.
  • Mammography Compliance for Arizona and New Mexico Hispanic and American Indian Women, 2016-2018

    Harris, Robin; Seanez, Carol; Gachupin, Francine; Nuño, Tomas (The University of Arizona., 2022)
    IntroductionHispanics and American Indians (AI) experience lower breast cancer incidence than non-Hispanic White (NHW) women but experience later-stage diagnoses and lower survival rates. Findings suggest that more screening is needed to enhance early detection. This research aims to describe current breast cancer screening utilization for Hispanic and AI women living in the Southwestern United States. Aim 1 examines mammography compliance for these women by age and race/ethnic group. Aim 2 identifies factors associated with compliance for women between 50-74 years. MethodsSample-weighted 2016 and 2018 Behavioral Risk Factor Surveillance System (BRFSS) for Arizona and New Mexico was used to assess the United States Preventative Services Task Force (USPSTF) compliance for breast cancer screening and compared to other national compliance recommendations. Unadjusted and adjusted logistic regressions were used to calculate odds ratios (OR) and 95% confidence intervals (CI) to evaluate associations between mammography compliance and covariates by racial and ethnic group. Analyses were restricted to women 40 years and older and included only Hispanic, AI, and NHW women (n=12,830). Covariates were checked for collinearity. Potential confounding was evaluated utilizing the 10% change rule. ResultsNHW women reported the highest frequency of ever having a mammogram (93.5%) compared to Hispanic (85.7%) and AI (83.6%) women. Overall, 75.1% of Hispanic women 50-74 years of age reported a mammogram in the past two years (USPSTF compliant) compared to 73.9% of NHW and 71.0% of AI women. For women aged 40-49, 57.2% of NHW women reported mammograms in the past two years, compared to 54.5% of Hispanic and 45.3% of AI women. As for women greater than 75 years of age, 63.0% of Hispanic women 50-74 years of age reported a mammogram in the past two years compared to 60.4% of NHW and 55.5% of AI women. Among women 50-74 years of age, Hispanic, AI and NHW who reported having visited a doctor in the past 12 months had greater odds of being USPSTF mammography compliant than those who were not (OR=4.2, CI 2.4-7.2, OR=2.9, CI 1.4-5.6 and OR=3.2, CI 2.5-4.1, respectively). The same was seen for AI and NHW women who reported having current medical insurance (AI OR= 9.6, CI 3.7-25.0 and NHW OR=1.9, CI 1.1-3.9). A sensitivity analysis conducted by state returned consistent results for current medical insurance and visiting a health care provider in the past 12 months. State differences were not statistically significant. ConclusionOverall, 74% of women ages 50-74 were USPSTF compliant. Having visited a health care provider in the past 12 months was essential for compliance for all included racial/ethnic groups. However, AI and NHW women had statistically significant differences for ‘having a personal doctor,’ suggesting unique challenges faced by racial/ethnic groups when deciding to receive a mammogram.
  • The Impact of Right Atrial Pressure on Outcomes in Patients Undergoing Transjugular Intrahepatic Portosystemic Shunt

    Fallon, Michael B.; Bommena, Shoma; Knox, Kenneth; VanWagner, Lisa B. (The University of Arizona., 2022)
    Background and Aims: Single-center studies in patients undergoing transjugular intrahepatic portosystemic shunt (TIPS) suggest that elevated right atrial pressure (RAP) may influence survival. We assessed the impact of pre-TIPS RAP on outcomes using the Advancing Liver Therapeutic Approaches (ALTA) database.Approach and Results: 883 patients in ALTA multicenter TIPS database from 2010-2015 from 9 centers with measured pre-TIPS RAP were included. Primary outcome was mortality. Secondary outcomes were 48-hour post-TIPS complications, post-TIPS portal hypertension complications, and post-TIPS inpatient admission for heart failure (HF). Adjusted Cox Proportional hazards and competing risk model with liver transplant as a competing risk were used to assess RAP association with mortality. Restricted cubic splines were used to model non-linear relationship. Logistic regression was used to assess RAP association with secondary outcomes. Pre-TIPS RAP was independently associated with overall mortality (sHR 1.04 per mmHg, 95% CI 1.01, 1.08, P=0.009) and composite 48-hour complications. RAP was a predictor of TIPS dysfunction with increased odds of post-90-day paracentesis in outpatient TIPS, hospital admissions for renal dysfunction and HF. Pre-TIPS RAP was positively associated with MELD, BMI, Native American and Black race, and lower platelets. Conclusions: Pre-TIPS RAP is an independent risk factor for overall mortality following TIPS insertion. Higher pre-TIPS RAP increased the odds of early complications and overall portal hypertensive complications as potential mechanisms for the mortality impact.
  • Secreted Frizzled Related Protein 4 (SFRP4) Modulates Cell Proliferation by Promoting Migration in Colon Cancer Tumorigenesis In Vitro

    Nfonsam, Valentine; Herman, Sara Elana; Heimark, Ron L.; Nelson, Mark A. (The University of Arizona., 2022)
    Background Colon cancer (CC) is one of the most common cancers diagnosed in the United States. Despite the decline of overall incidences, the number of early-onset colon cancer (EOCC, [age < 50]) cases continues to rise at an alarming rate. EOCC tends to have more aggressive features, often diagnosed at a more advanced stage, and is associated with a poorer prognosis. Previous genomic studies identify EOCC as a unique disease with specific differentially expressed genes compared to late-onset colon cancer (LOCC). Secreted Frizzle Related Protein 4 (SFRP4) was significantly overexpressed in EOCC (p < 0.01, log2 fold change 3.97) and correlated with poor survival (p < 0.05) as well as increased tumor aggression. However, the role of SFRP4 of CC tumorigenesis, especially in those younger than 50 years, is not well understood. Therefore, the aim of this study was to evaluate the role of SFRP4 in CC tumorigenesis by modulating SFRP4 levels in vitro and determine how it affects proliferation and migration.Methods Cell lines were profiled for SFRP4 to choose an appropriate in vitro model to evaluate the role SFRP4 on CC tumorigenesis. A single cell line, Caco-2 (low SFRP4 expression), was chosen for proliferation and migration studies in vitro. Results Cell proliferation was decreased in Caco-2 cells upon treatment with human recombinant SFRP4 (rhSFRP) after 72 h (p <0.001). Transwell migration assay revealed significant increase in motility of Caco-2 cells after 24 h upon treatment with SFRP4. Conclusion Overexpression of SFRP4 modulates proliferation by promoting migration in Caco-2 cells, likely inducing epithelial-mesenchymal transition, which increases metastatic potential.
  • Cavitation and cavitation damage

    Rogers, W. L.; Wang, Shih-cheng, 1938- (The University of Arizona., 1965)
  • Monolithic Three-Mirror Anastigmat Telescope

    Kim, Daewook; Han, Yuqiao; Choi, Heejoo; Kupinski, Meredith (The University of Arizona., 2023)
    This thesis presents the design of a near-infrared (near-IR) three-mirror anastigmat telescope with a focal length of 38,675.1 ??, an entrance pupil diameter of 1,933.75 ??, and a 0.12° full field-of-view (FoV). This diffraction-limited telescope has a RMS spot radius of 36.6 μm (similar to the radius of Airy disk) to satisfy the design resolution requirements of the IR telescope. Designed specifically for near-IR sensing, the system benchmarked a widely known module of an IR detector, called the Near-Infrared Camera (NIRCam) detector, with ten Teledyne HgCdTe H2RG detectors. The NIRCam detector was assumed in this TMA design study, similar to the James Webb Space Telescope case. This three-mirror telescope design contains only two substrates, one consisting of two mirror surfaces with different radii of curvature. Consequently, the structure of this robust telescope design is straightforward and it is therefore easy to manufacture and align. The starting point for the optical design of this telescope was the Vera C. Rubin Observatory (a.k.a. Large Synoptic Survey Telescope), a three-mirror anastigmat system combined with more refractive lenses and a color filters. Importantly, the specifications of these three mirrors were changed to achieve the goal of aberration balancing. To determine the tolerances of the optical design, the M2 mirror substrate was misaligned with respect to the M1/M3 monolithic mirror, and the realistic maximum error was evaluated. As a result, in the range of 36.6 ?? root mean square (RMS) spot radius for the three degrees of freedom (DoF), the calculated tolerances were 0.0072° for X-rotation, 43 µ? for Y-translation, and 7.6 µ? for Z-translation. This result confirmed that the required machining accuracy to build the proposed telescope is within the advanced optical fabrication (e.g., diamond turning) and modern integration capabilities.
  • Efficacy of Chlorine and Peracetic Acid to Reduce Shiga Toxin-Producing Escherichia Coli and Impact of Simultaneous Nitrogen-Based Fertilizer Use on Microbial Die-Off in Preharvest Agricultural Water

    Rock, Channah; Scott, Zoe; Cooper, Kerry; Gerba, Charles (The University of Arizona., 2023)
    Several foodborne disease outbreaks in the United States have been linked to the consumption of various types of leafy greens in which irrigation water was suspected as the potential source of contamination. To reduce potential produce contamination from agricultural water, the U.S. Food and Drug Administration (FDA) has proposed regulations/metrics which would require growers to assess their agricultural water systems. In some cases, this would mean monitoring their water quality and taking corrective action, by way of antimicrobial treatments, when agricultural waters are deemed as a “reasonably likely foreseeable hazard”. Additionally, the Arizona and California Leafy Greens Marketing Agreements (AZ/CA LGMA) require growers utilizing surface water for overhead irrigation to treat their water within 21 days of harvest to meet acceptable risk indicators; generic Escherichia coli (E. coli) (non-detect per 100mL) and Total Coliform bacteria (<99 MPN/100mL). For many growers, this will be the first time that water quality data may necessitate them to use an antimicrobial treatment before irrigation can be applied safely. Additionally, growers are faced with a myriad of options related to antimicrobial water treatment with very little guidance on the most appropriate treatment option for their ranch, or the requirements needed for successful implementation. With limited guidance, water treatment decisions are likely to be unsuccessful and expend both excess time and money while seeing little to no reduction in potential pathogen loading in an agricultural water source and thus little to no reduction in microbiological risk. To provide guidance on antimicrobial agricultural water treatment options available to industry, the efficacy of two antimicrobial treatments Peroxyacetic Acid (PAA) and Calcium Hypochlorite (Cl) were tested, in triplicate. Tests were executed for various rates of each antimicrobial product (sanitizer), 6 & 8 PPM for PAA and 2 & 4 PPM for Cl. For each sanitizer at each PPM, tests were conducted at temperatures 12°C and 32°C. To evaluate sanitization efficacy, the team measured the reduction of a 109 CFU/mL cocktail of Shiga toxin-producing E. coli (STEC) strains (ATCC MP-9 and 43895) in four water sources from across the southwestern United States (Yuma and Maricopa, AZ, Uvalde and Edinburgh, TX). Four different water sources were used to gauge if water quality impacted sanitization efficacy. The experimental design was based on an EPA/FDA protocol to assess the efficacy of an antimicrobial product to reduce foodborne bacteria in pre-harvest agricultural water (https://www.fda.gov/media/140640/download) . This protocol dictates that STEC cocktail be added to agricultural water then equilibrated at either temperature (12°C or 32°C); post equilibration, each sanitizer, for each concentration, is injected into the mixed solution. The appointed contact time (1 or 5 minutes) is given and then the solution is neutralized and evaluated. To further growers’ comprehension of best management practices for successful antimicrobial treatment application, the impact of two nitrogen-based fertilizers (UAN32 and CAN17) on the efficacy of Sodium Hypochlorite 6% (chlorine) and PAA against naturally occurring coliforms was also evaluated. The first study provides evidence that chlorine meets EPA’s required 3-log reduction of pathogens in order to receive label approval. At a one-minute contact time, the chlorine treatment resulted in log reduction values (LRVs) ranging from 3.24 to 6.15 regardless of temperature, dose/PPM, or water source. PAA however did not perform as well with LRVs ranged from 0.0 to 1.10 with higher reduction occurring at the higher temperature and dose of PAA. When the contact time of PAA treatment was increased to five minutes, LRVs increased and ranges from 1.5 to 5.4 were observed; the efficacy of the sanitizer increased with increased solution temperature. Furthermore, the addition of nitrogen-based fertilizer to the water source in tandem with treatment application significantly affected the antimicrobial capabilities of chlorine. For chlorine, when applied unaccompanied an average log reduction of 3 logs was seen. However, LRVs decreased on average by 1.34 logs when fertilizer was introduced: with the greatest reduction in efficacy resulting in a nearly 2-log decrease. Contrarily, combined application of PAA and either fertilizer showed little to no interaction with a 0.4 log increase in disinfection efficacy when UAN32 was used. Results indicate that a prolonged contact time may be needed to meet regulations when PAA is used as an antimicrobial treatment. As well, growers must be cautious when applying fertilizer conjointly with antimicrobial treatment to their agricultural waters to ensure compliance with new proposed food safety metrics.
  • Structural and Diffusion MRI to Study the Effects of Hypertension in Rat Brain Macrostructure and Microstructure

    Trouard, Theodore; Wiskoski, Haley Elizabeth; Hutchinson, Elizabeth; Chen, Nan-kuei (The University of Arizona., 2023)
    Hypertension (HTN) is associated with an increased risk of cardiovascular disease (CVD) and cognitive decline in aging humans, with onset occurring around middle age, and responsible for roughly 7 million deaths worldwide, annually. Prior research has also shown that mid-life HTN is associated with negative effects on brain structure and function in late life. Therefore, it is important to study the symptoms of HTN on the central nervous system as the disease progresses with age, and specifically how this may affect neurological anatomy, development, and function. Animal models are an integral tool in preclinical, translational research of the human body, facilitating greater understanding, treatment, and prevention of diseases such as HTN. The Fischer-344 Cyp1a1-Ren2 transgenic xenobiotic-inducible rat model is an appreciable strain in studies of HTN due to the fact that the induction of increased blood pressure, as induced via the administration of dietary molecule Indole-3-Carbinol (I3C), is reversible, controllable, and dose-dependent in magnitude. The purpose of this study was to investigate the longitudinal effects of induced HTN in macrostructural and microstructural neuroanatomy of F344 Cyp1a1-Ren2 transgenic rats through the use of noninvasive diffusion-weighted MRI (dMRI) and imaging analyses. Results of this study show that even in the face of sustained increases in blood pressure and end-organ damage in the heart and kidney, a majority of the brain remained unaffected in terms of volume and microstructural characteristics. This indicates the presence of an intrinsic, protective mechanism of the brain in this model, forestalling the onset of detrimental effects of HTN on brain structure and function.
  • Gender Identity and Expression in Drum Corps Performance: An Ethnographic Study of Performers' Experiences

    Gubner, Jennie; Frew, Johnathan; Alexander, Kathryn; Mora, Amalia (The University of Arizona., 2023)
    This project seeks to understand how gender is constructed, performed, and experienced through participation in drum corps. Drum corps is a North American youth performing arts practice in which musicians and dancers perform themed marching band shows throughout the United States and are judged competitively against one another. The data used in this project comes from four weeks of ethnographic fieldwork with the Blue Knights drum corps during the summer of 2022. Personal accounts from the corps’ members and staff, fieldwork photographs, and the author’s observations are analyzed in this project to explore performers’ experiences with gender in drum corps.

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