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The Impact of Dietary Fibers and Environmental Xenobiotics on Metabolic Homeostasis Via the Gut Microbiota
No full textThe global rise in obesity and type 2 diabetes (T2D) is strongly linked to diet and environmental exposures that influence host metabolism and the gut microbiota. Dietary fibers, including beta-glucan, pectin, wheat dextrin, and resistant starch, are fermented by gut microbes into short-chain fatty acids that regulate energy balance and glucose homeostasis. However, fibers are heterogeneous in structure and function, and their independent effects on metabolism and the gut microbiota remain unclear. In parallel, environmental xenobiotics such as glyphosate, the most widely used herbicide, and chlorination agents used in drinking water, can disrupt microbial composition and promote inflammation, yet their long-term, sex-specific, and diet-dependent impacts on metabolic health are poorly defined.This dissertation examines how environmental factors shape host-microbiota interactions and contribute to metabolic disease. Chapter 1 reviews the role of the gut microbiota in regulating metabolic homeostasis. Chapter 2 investigates how distinct dietary fibers influence host metabolism through microbiota-mediated mechanisms. Chapter 3 explores the effects of glyphosate exposure on the gut microbiota and metabolic outcomes. Chapter 4 focuses on the impact of chlorinated drinking water on metabolic homeostasis through changes in the gut microbiota. Together, these studies provide new insight into how diet and environmental exposures modulate host-microbe interactions and impact metabolic health
Rediscovering Charles Samuel Bovy-Lysberg: A Journey Through Romantic Swiss Piano Works
No full textThis document explores the life and music of Charles Samuel Bovy-Lysberg (1821–1873), situating his work within the broader context of the Romantic era. Bovy-Lysberg’s compositions draw considerable inspiration from Frédéric Chopin and Franz Liszt as well as other composers including Felix Mendelssohn—an inheritance that emerges in his lyrical melodies, sophisticated harmonic language, and expressive piano writing. By weaving these influences into a distinctly personal style, Bovy-Lysberg’s music embodies quintessential Romantic ideals while showcasing an individuality that merits greater recognition.This study focuses on three of his works from an output of over 150 solo piano pieces, analyzing their melodic and structural elements in comparison with similar Romantic repertoire—such as Mendelssohn’s Songs Without Words, Chopin’s Nocturnes, and Liszt’s character pieces. By examining how Bovy-Lysberg’s music balances cantabile expression with technical virtuosity, this critical essay contends that his compositions belong alongside the widely performed Romantic piano canon. Through comparative analysis, this critical essay highlights the influence of Chopin’s, Liszt’s, and Mendelssohn’s pianistic innovations on Bovy-Lysberg’s writing, affirming his artistic contribution beyond his native Switzerland. Ultimately, this critical essay aims to reintroduce Bovy-Lysberg to modern scholarship, positioning him not as a Swiss composer with only regional significance, but as an overlooked Romantic figure whose music merits renewed attention
Experimental Investigation of Boundary-Layer Transition in High-Speed Two-Dimensional Boundary Layers
No full textThis dissertation focuses on Mack’s first- and second-mode instabilities in planarboundary layers. Experiments were first conducted on a flat plate in the Quiet Mach 4 Ludwieg Tube at the University of Arizona. Data showed presence of first-mode waves, but the amplitudes were too low to cause the boundary layer to transition. The frequency and wave angle of these first-mode waves agreed well with theory. No second-mode waves were detected in these experiments. The Reynolds number in this facility was too low to perform meaningful boundary-layer transition experiments.
As such, experiments were then conducted on a hollow cylinder in the Mach 5 Ludwieg Tube at the University of Arizona, which has a larger maximum Reynolds number. In this conventional wind tunnel, the transition from a laminar boundary layer to a turbulent boundary layer was observed. The unit Reynolds numbers for these experiments ranged from Re′ = 6.5 × 106m−1 to 18.5 × 106m−1. The experimental data show evidence of the first and second modes in this boundary layer, as predicted by linear stability theory. The main instrumentation used in the experiments were surface pressure transducers and Z-type schlieren imaging. The pressure data showed spectral content in frequency bands where linear stability theory (LST) predicts the second mode to exist. The second mode becomes unstable at the locations predicted by LST and the experimentally measured second-mode growth rates agree well with second-mode growth rates from LST. The first-mode waves did not produce a significant signal in the pressure data, which is expected since these waves are often difficult to detect with surface pressure sensors. However, wave angle calculations performed on the pressure data in the predicted first-mode frequency range showed an oblique wave angle that was consistent with the first-mode
wave angles of LST. First-mode structures were pronounced in the schlieren data and their shape and wavelength agree with LST amplitude reconstruction. The second-mode waves show some resemblance to the structures predicted by LST, but there are subtle differences as well. Nonlinear analysis of the pressure data was conducted to understand the ultimate breakdown mechanism. It appears that an interaction between low-frequency first-mode waves that starts around Rex = 2×106 is causing boundary-layer transition. The Reynolds transition number measured was
approximately Rex = 3.5 × 106
A HABITAT SUITABILITY ANALYSIS OF THE KIT FOX IN COLORADO
Full text linkAs human population continues to increase, cities will keep growing and more critical wildlife areas will be transformed for urban development. As this progresses and more wildlife species become endangered, conservationists will play a vital component in the future development expansions and help to maintain ecosystems. One of those already endangered species is the Kit Fox (Vulpes macrotis), which plays an important role in keeping Colorado’s ecosystem in balance. Due to urban development as well as other human factors such as roads/driving, the Kit Fox’s population continues to dwindle, placing them on the Colorado Threatened and Endangered List. This project conducts a suitability analysis within the state of Colorado to determine suitable locations for Kit Fox populations to be moved to for conservation efforts. Using a variety of different factors that pertain to the Kit Fox’s survival needs as inputs, both a binary and a weighted suitability method were conducted to find alternative suitable locations for the Kit Fox to thrive in within Colorado. Future conservationists and scientists can use the results from this study to assist with recommendations to move Kit Fox populations to restore their population numbers, remove them from the Colorado Threatened and Endangered List, and keep the Kit Fox from vanishing in Colorado.This item is part of the MS-GIST Master's Reports collection. For more information about items in this collection, please contact the UA Campus Repository at [email protected]
A SmallSat Approach to Deep-Space Exploration: The Enceladus Chirp Orbiter (ECHO)
No full textWith the recent advent of commercial space companies, there is increased interest in space exploration and spaceflight technologies. In planetary science, the field of astrobiology is becoming more popular as well. Astrobiologists aim to understand how life developed on Earth, and where habitable environments could exist elsewhere in the solar system and beyond. However, even with all of this interest in space exploration, very few spacecraft have traveled to the outer solar system. This is due to several reasons, but mainly due to the complexities and cost of large missions designed for deep space. Past deep-space missions have tended to be large and expensive; the science returns are incredible, but the price is discouraging. The Enceladus Chirp Orbiter (ECHO) has been designed to be a small, less-expensive orbiter for deep-space exploration, to shift away from the paradigm of large, heavy, and costly deep-space flagship missions. The main science goal of this mission is to use a novel chirp radar experiment (DARE, or the Differential Absorption Radar Experiment) to search for biomarkers in the plumes of the Saturnian moon, Enceladus. The work discussed here details a concept study for the ECHO mission. First, the science rationale for this mission will be discussed, as well as how the DARE instrument functions and its planned operations. Second, the spacecraft design and components will be defined. This will be accomplished through analysis of both off-the-shelf and custom hardware and software. Technologies are leveraged from prior NASA deep-space missions, as well as small satellite (SmallSat) missions,
especially those flown and tested on the University of Arizona’s low-Earth orbiting CatSat satellite. Third, a deployable K-band communications dish concept based on CatSat technologies and lab work will be discussed. Next, the trajectory analysis for the mission will be explored, leveraging from past missions to Saturn and beyond, as well as an opportune Jupiter gravity assist occurring in the late 2030’s and early 2040’s. Lastly, ongoing CatSat and LunaCat work, as well as future work to advance ECHO and the DARE technology will be discussed.Release after 08/21/202
Phenotypic Characterization of a New Rat Model of Catecholaminergic Polymorphic Ventricular Tachycardia Type 3
No full textA spectrum of inherited and acquired cardiovascular disease can cause sudden cardiac death from calcium (Ca2+)-dependent ventricular arrhythmias. These arrhythmias are largely driven by hyperactivity of the sarcoplasmic reticulum (SR) Ca2+ release channel, the cardiac ryanodine receptor (RyR2). Treatment options to attenuate arrhythmia are limited or of poor efficacy. Therefore, it remains a priority to understand molecular mechanisms underlying RyR2 hyperactivity in disease for improved therapeutic design. Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare type of arrhythmia that has a lethal phenotype associated with Ca2+ mishandling. The disease typically presents in juveniles as ventricular tachycardia and fibrillation after stress or exercise, which can lead to sudden cardiac death. Mutations associated with CPVT are typically in RyR2 or its accessory proteins. CPVT3 is a recently reported subtype of the condition associated with mutations in trans-2,3-enoyl-CoA reductase-like protein (TECRL). Little is known about the function of TECRL in the heart, other than its localization to the sarcoplasmic reticulum. It remains entirely unknown how mutations in TECRL lead to an arrhythmogenic phenotype associated with intracellular Ca2+ mishandling and RyR2 hyperactivity. Here, we developed a new rat model of CPVT3 using CRISPR-Cas9 to introduce a patient-asssociated TECRL mutation, the single nucleotide polymorphism c.331+1G?A. Our studies with homozygous TECRL-SNP rats revealed no global cardiac remodeling, typical of the CPVT phenotype. Importantly, the rat exhibits a strong arrhythmogenic phenotype, presenting with VTs after challenge with epinephrine and caffeine. In contrast to other types of CPVT, these rats also presented with premature ventricular contractions even at baseline conditions. Confocal microscopy revealed that TECRL-SNP leads to RyR2 hyperactivity and intracellular Ca2+ mishandling, although the molecular mechanism underlying this remains unclear. Overall, we demonstrate that the TECRL-SNP rat has a strong arrhythmogenic phenotype for future studies of CPVT3.Release after 10/02/202
Increasing Provider Awareness of Evidence-Based Screening Tools to Identify Insomnia
No full textBackground: Insomnia (poor sleep) is a highly prevalent patient-reported symptom that impactsnearly every health-related metric. In its persistent forms, patients may have symptoms meeting DSM-5-TR criteria for a sleep-wake disorder. As a symptom, it is often under-assessed, under-diagnosed, and under-treated, predisposing individuals to have persistent and worsening manifestations and subsequently develop physical health illnesses and mental health disorders. Standardized screening across diverse health conditions, such as insomnia, has been shown to improve recognition, diagnostic accuracy, tailored treatment planning, and patient outcomes. As the basis for standardized screening and the ISE intervention for this project, the ISI, a validated self-report questionnaire designed to assess the severity of insomnia symptoms in clinical practice, was implemented. Purpose: The aim of this quality improvement (QI) project was to evaluate an educationalintervention to motivate clinician use of a validated, evidence-based screening tool, the Insomnia Severity Index (ISI). The overall goal was to improve the identification of insomnia among clinic patients. The Insomnia Severity Education (ISE) intervention was designed to enhance healthcare provider outcomes of 1) insomnia screening knowledge, 2) confidence in using the ISI, and 3) intention to incorporate insomnia screening, specifically the ISI, into routine clinical practice.
Methods: An evaluative design utilizing pre- and post-intervention measures was employed toassess the effectiveness of the ISE intervention in enhancing provider knowledge of insomnia screening, confidence in using the ISI, and intention to incorporate insomnia screening, specifically the ISI, into clinical practice. Healthcare providers from a community health center in southern Arizona were invited to participate voluntarily, with three providers completing all components of the intervention. The link to the ISE intervention was distributed through the organization’s internal email system. Descriptive statistics were used to evaluate and interpret the survey data. Results: Post-intervention survey responses indicated increases in healthcare providers'knowledge of insomnia screening, confidence in using the ISI, and intent to implement the ISI in clinical practice. Descriptive statistics revealed positive shifts in all three domains, with providers reporting increased familiarity with the ISI and its clinical applications. The anonymous, self-matched pre- and post-surveys demonstrated that a brief, asynchronous educational intervention was effective in promoting awareness and readiness for practice change. Conclusions: The findings suggest that brief, asynchronous education can be an effectivestrategy for enhancing provider knowledge and confidence in screening for insomnia. The increase in intention to incorporate the ISI into clinical assessments highlights the potential of targeted educational interventions to support the adoption of evidence-based tools in everyday practice. These results support the feasibility and value of integrating insomnia screening into routine care through provider-focused education
Columnar to Equiaxed Transition in Spot Melt Electron Beam Powder Bed Fusion Scan Strategy and Utilization of Microstructure Informatics
No full textElectron beam powder bed fusion (EB-PBF) has significant potential for achieving controlled microstructural development in additively manufactured components while addressing anisotropic mechanical property limitations inherent to conventional powder bed fusion processes. This work evaluated the columnar-to-equiaxed transition behavior and microstructural refinement characteristics of spot melt scanning strategies in EB-PBF processing. IN718 specimens were processed using four distinct scanning patterns and subjected to comprehensive microstructure informatics analysis to examine relationships between processing parameters, thermal management, and resulting grain morphology characteristics. Specimens underwent systematic beam current and dwell time variations to investigate the influence of energy density on microstructural evolution mechanisms. In addition, traditional raster scanning was examined to provide context for comparison with the experimental spot melting approaches. Microstructural characterization was performed using electron backscatter diffraction (EBSD) combined with quantitative informatics methodologies, in which comprehensive statistical analysis of grain dimensions and aspect ratios was conducted to establish processing-structure relationships. Aspect ratio measurements for the spot melting specimens were found to vary by factors of two to four compared with traditional raster scanning results, demonstrating the effectiveness of temporal separation strategies for columnar-to-equiaxed transition control. Scanning pattern configuration did not indicate a significant impact on densification behavior when adequate energy density was maintained. Moreover, equiaxed microstructural development appeared predominantly in specimens with optimized temporal separation between adjacent melt events as confirmed through three-dimensional EBSD reconstruction analysis. The work presented provides systematic assessment of the relationship between spot melting processing conditions, resulting microstructural characteristics, and thermal management strategies, while offering insight into development pathways for improved mechanical isotropy in this technologically important manufacturing process
Vertical Radiative Cooling Enabled by Reflective Mirror Geometry and Spectrally Selective Physical Modeling
No full textRadiative cooling is a passive cooling method that can reduce electricity use by emitting heat into outer space through the atmospheric transparency window (8–13?µm). Most current designs use horizontal emitters, which are limited by rooftop space in cities. In contrast, vertical surfaces such as building façades are more abundant, but have received little attention due to fundamental physical limitations: they suffer from restricted sky exposure and increased absorption of thermal radiation from the ground and surrounding structures, which significantly reduce net cooling performance when analyzed using conventional models. In this study, we propose a new physical model for vertical radiative cooling, incorporating angular and spectral selectivity as well as geometrical view factor constraints. Based on this model, we design a vertical radiative cooling system that uses angularly and spectrally selective emitters, combined with a reflective mirror placed below the emitter. This design improves the effective emission angle and blocks thermal radiation from the ground. Simulation results show that under typical urban conditions like Phoenix, Arizona, USA (30 °C ambient, atmospheric transmittance ? = 0.8, parasitic heat coefficient h = 0.8?W/m²·K), the system can achieve a net cooling power of 16.13 W/m². We also show that with four vertical panels and one horizontal emitter, the system can deliver over 1 kW of total cooling power. Even without rooftop components, a vertical surface area of 62 m² is enough to reach kilowatt-level cooling. These results suggest that vertical radiative cooling is a practical and scalable solution for reducing cooling energy use in dense urban areas, enabled by a physics-based framework tailored to vertical emitter geometry
Guidelines for Asian Citrus Psyllid and Citrus Greening Disease Management in Commercial Citrus Production
No full textCitrus growers are essential to protecting Arizona’s citrus industry from the spread of HLB. Consistent monitoring for ACP and early disease symptoms, combined with timely and effective management practices, can significantly reduce the risk of infection. Reporting infected trees to the appropriate authorities and following recommended control strategies can help prevent the spread of both the vector and the disease. Cooperation of growers and pest control advisors is vital; HLB management is most successful when efforts are coordinated across regions. By staying informed and proactive, we can help preserve the health, productivity, and future of citrus groves across the state. Your actions make a lasting impact