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Item Open Access Investigations Into Selective Laser Melting of Silicon Carbide-Silicon Dioxide Ceramic Composites(2024-08-01) Brownlee, Sean; Liu, Yingtao; Garg, Jivtesh; Billings, ChristopherThis investigative thesis explores the potential of leveraging Selective Laser Melting (SLM) with silicon-based ceramic substrates to form three-dimensional silicon-based glass-ceramic composite parts. A Selective Laser Processing (SLP) machine was developed to conduct experimental research. The machine was utilized to study the effects of silicon dioxide (SiO2) additive in silicon carbide (SiC) substrates as well as the effect of Scanning Energy (SED) on resulting fabricated line widths and fabricated line uniformity. Preliminary and experimental fabricated line width prediction models as functions of SED, substrate SiC content, and scale of SiO2 particulate additive in the substrate were created. The machine was also utilized to study the effects of SED and scanning strategy on defect formation in fabricated square specimens. It was found that by SLM, melt pool formation and melt pool solidification occurred in substrates containing primarily SiC. Additionally, successful bonding of joints, common in SLM of three-dimensional components, was demonstrated. The exact chemical composition of the final fabricated specimens remained unclear; however, some evidence pointed to the subversion of sublimation of SiC in standard atmosphere under rapid heating and cooling cycles. The results provide a platform for future investigations in SLM of SiC and can be used as an impetus for increasing efforts to account for and control the process parameters involved. It is expected that with increased experimental, theoretical, and numerical modeling, as well as increased control of process parameters, the fabrication of three-dimensional components by SLM is possible using SiC substrates.It was found that by SLM, melt pool formation and melt pool solidification does occur in substrates containing primarily SiC. also, successful bonding of joints, common in SLM of three-dimensional components, was demonstrated. The exact chemical composition of the final fabricated specimens remains unclear; however, evidence pointed to the subversion of sublimation of SiC in standard atmosphere under rapid heating and cooling cycles. The results provide a platform for future investigations in SLM of SiC and provide an impetus for increasing efforts to account for and control the process parameters involved. It is expected that with increased experimental, theoretical, and numerical modeling, as well as increased control of process parameters, the fabrication of three-dimensional components by SLM is possible using SiC substrates.Item Open Access Fantastic Herbals and Where to Find Them: Contextualizing and Expanding the Alchemical Herbal Tradition(2024-08-01) Beasley, Bryce; Vermij, Rienk; Magruder, Kerry; Endres, BillA collection of 38 herbal manuscripts have remained all but hidden to scholars in the shadow of the Italian Alps. Despite several texts analyzing specific texts (Leporace, 1952, Lupo 1982, Ragazzini 1983, Toresella 1985, Pezzella 2007 and Bruzzone 2015, 2019) and one pioneering work which synthesizes a large portion of them as united in the corpus (Segre 2000), the “alchemical herbal tradition” has so far escaped examination through methodologies employed in the history of science, medicine and magic. The 98 alchemical herbs described in the tradition demonstrate a complex and nuanced medieval approach to astrology, natural and vernacular magic, botanical medicine, religion and alchemy. However, there is far less of this final category than one might expect to find in a manuscript tradition named after the discipline. The present work adds 14 alchemical herbals to the 24 manuscripts examined by Vera Segre’s foundational census of the tradition in an effort to improve the body of evidence available for analysis and comparison. In addition to using existing frameworks and methodologies from the history of medical botany, we find that these manuscripts can be better understood by applying terms such as magiferous and natural magic, placing them squarely within their cultural and intellectual contexts of the Italian Quattrocento. By analyzing individual plants across the full collection of manuscripts, changes in their medical uses, occult properties, and fantastic illustrations can be traced to provide better understanding of the lived histories of their manuscripts and owners. This is a preliminary study examining the theoretical foundations underpinning this large and varied collection of herbals, with the aim of one day understanding who the supposed alchemists were that created these enigmatic codices.Item Open Access Characterizing the Effects of Land Cover Changes on the Spatiotemporal and Microphysical Properties of Convective Cells in Houston, Texas(2024-08-02) Omitusa, Oluwafemi; Bodine, David; Kirstetter, Pierre Emmanuel; Lebo, ZacharyThis study examines the behavior and microphysical properties of convective cells across different environments in the Houston metropolitan area during summer 2022. Using KHGX NEXRAD radar observations of 22,372 cell tracks, convective properties were analyzed across upwind, urban, and downwind regions. The upwind region, dominated by coastal processes, exhibited peak cell initiation during early morning hours (80% of total cells) with smaller (42.5 km²), less intense (36 dBZ) cells. The urban region showed approximately double the number of initiated cells per unit land area compared to upwind and 4–5 times more than downwind regions. Urban-influenced cells displayed greater variability in hydrometeor characteristics, larger mean raindrop sizes (ZDR ∼ 1.8 dB), and higher liquid water content (KDP ∼ 1.4 deg/km). Despite more frequent initiation, urban cells had lower precipitation efficiency. The downwind region demonstrated the highest precipitation efficiency (30 mm/cell) despite lower cell density. Analysis of cell lifecycles revealed distinct patterns across regions. Urban impacts persisted downstream, with cells maintaining higher intensities through mature and dissipating stages. Upwind cells showed more uniform microphysical characteristics throughout their lifecycle, while downwind cells exhibited extended vertical development of ice particles during the developing and mature stages. This research advances understanding of how urban environments alter precipitation formation mechanisms and how the combined effects of sea breeze and urban heat island influence the spatiotemporal evolution of convective storms. It also highlights the need for further investigation into the combined effects of sea breeze and urban heat island on convective storm evolution.Item Open Access NBA TICKET PACKAGE OPTIMIZATION, A CASE STUDY OF THE CLEVELAND CAVALIERS(2024-08-01) Levicki, Benjamin; Nicholson, Charles; Shehab, Randa; Beattie, MatthewThe purpose of this study is to create a genetic algorithm to further enhance the current half season ticket packaging process in the event industry through a case study with the Cleveland Cavaliers of the National Basketball Association. The focus of this study is on the integration of machine learning and heuristic methods to simulate the human decision making currently taking place across the industry. This study will cover the methodologies being proposed for the overall, integrated approach. The methods that we cover in this study surround the tiering of events using K-Medoids and the makeup of the genetic algorithm that was implemented to solve for optimal half season packages using the Cleveland Cavaliers home schedule. Then, using the interaction between these two methodologies, we analyze the results in collaboration with domain experts from the Cavaliers. This study will show how the usage of machine learning paired with a genetic algorithm can affectively simulate and improve upon the current process for determining half season ticket packages. Furthermore, future improvements, such as the addition of predictive analytics and fan behavior are explored to supplement this work and lead to future areas of research and development.Item Open Access Killer Queers: A Content Analysis of Queer Serial Killers in the News(2024-08-01) Reynolds, Broghan; Hope, Trina; Shrap, Susan; Kroutter, PaulThis study examines how offenses by queer serial killers were addressed by law enforcement through the eyes of the media. The analysis focuses on infamous serial killers John Wayne Gacy and Jeffrey Dahmer to analyze how the criminal justice system handled their cases through news article documentation. The study aims to explore how the media shapes the narrative surrounding queer identities when they become offenders. The study discusses how homophobia serves as a driving force for upholding negative stereotypes of an entire community. The content analysis shows how the media responded to the serial killers in terms of their sexual identities.Item Open Access Additive Manufacturing of Ti-64 Using Selective Laser Melting(2024-08-01) Nimmo, Caylin; Billings, Christopher; Liu, Yingtao; Siddique, ZahedSelective Laser Melting (SLM) is an Additive Manufacturing (AM) process that is seeing adoption in many engineering industries, namely in biomedical, automotive, and aerospace applications. In this work, the capabilities of the General Electric (GE) Additive Concept M2 Series 5 Titanium Ti-64 Grade 23 SLM printer are characterized in a preliminary study to guide future research and processes at the Sooner Additive Manufacturing Laboratory (SAML). Ti-64 (90% titanium, 6% aluminum, 4% vanadium by weight) AM has become more accessible in the last decade and is of particular interest to the United States Air Force for fabricating replacement parts for aging aircraft. This work focuses on reviewing the Powder Bed Fusion (PBF) process and determining the bulk tensile properties of horizontally printed specimens using GE’s provided parameters while expanding the capabilities of the SAML to prepare it for additional testing. As printed samples were compared to all 3 of the Stress Relief (SR) options provided by GE alongside a study to evaluate the potential for shot peening using resources readily available in the laboratory. Samples were evaluated using Digital Image Correlation (DIC) during the loading processes and a universal testing system. Samples were shown to present properties similar to that of the provided GE specifications, but fell short of the published values for as printed and SR3 samples for the Balanced Parameter 114. In-house polishing processes were expanded to successfully present Ti-64 grain structures under optical microscopy and Scanning Electron Microscopy (SEM) by decreasing the final polishing particle size to 0.02 μm and including additional particle sizes during preparation (9 μm, 6 μm, 3 μm, 1 μm, 0.05 μm, 0.02 μm). Future work should and will include a larger sample size for each specimen type and utilize ASTM E8M specimens.Item Open Access Cannibalistic Society: Studying social behavior and learning under high social risk(2024-08-01) Gatch, Laura; Stein, Laura; Bentz, Alexandra; Hung, Keng-Lou James; Fuenzalida, Luz-EugeniaRisks of sociality, including competition and conspecific aggression, are particularly pronounced in venomous invertebrates such as arachnids. Spiders show a wide range of sociality, with differing levels of cannibalism and other types of social aggression. To have the greatest chance of surviving interactions with conspecifics, spiders must learn to assess and respond to risk. One of the major ways risk assessment is studied in spiders is via venom metering, in which spiders choose how much venom to use based on prey and predator characteristics. While venom metering in response to prey acquisition and predator defense is well-studied, less is known about its use in conspecific interactions. In Chapter 1, I discuss that due to the wide range of both sociality and venom found in spiders, they are poised to be an excellent system for testing questions regarding whether and how venom use relates to the evolution of social behavior and, in return, whether social behavior influences venom use and evolution. I focus primarily on the widow spiders, Latrodectus, as a strong model for testing these hypotheses, and my hypotheses in Chapter 2. In Chapter 2, I test for the presence of aversion learning, a risk-management tool, in Latrodectus mactans juveniles. Although no aversion learning was evident from the results, there were potential signs of other, nonassociative learning types. The results indicate that aversion learning is not utilized by juvenile L. mactans to reduce the risk of cannibalism in the social environment, leaving the question of how L. mactans maintains sociality while mitigating risk open. Given that successful responses to risk are vital for maintaining sociality, comparative analysis of spider taxa in which venom metering and sociality vary can provide valuable insights into the evolution and maintenance of social behavior under risk.Item Open Access Impact of Assimilating Lower Atmospheric Boundary Layer Observations from Uncrewed Aerial Systems on Short-Term Probabilistic Predictions of a Tornadic Supercell Event(2024-08-01) Tweedie, Jordan; Yussouf, Nusrat; Xue, Ming; Klein, PetraOne limitation of convective-scale NWP ensemble modeling systems is the inadequate representation of the pre-convective and near-convective environment in the model, particularly in the lower level (0–2 km) of the atmospheric boundary layer (BL). This limitation is largely due to the unavailability of thermodynamic and kinematic BL observations with high spatial and temporal resolutions. This study aims to assess the impact of assimilating the emerging Uncrewed Aerial System (UAS) lower atmospheric BL measurements in convective-scale ensemble modeling systems. The case used to conduct the study is the violent EF4 24–25 March 2023 Rolling Fork tornado event. The event was sampled using various instrumentation during the PERiLS 2023 field campaign, including three CopterSonde UAS instruments located at three separate, stationary profiling sites near the Arkansas/Louisiana/Mississippi border. The CopterSondes collected lower atmospheric BL observations every 15–30 minutes, with cadence depending on storm motion and other environmental factors. Several retrospective experiments are conducted using the National Severe Storm Laboratory’s Warn-on-Forecast (WoFS) data assimilation and modeling system to assimilate temperature, dewpoint temperature, u-, and v-wind components from the CopterSonde in addition to all other routinely available observations in the baseline WoFS. Results indicate that assimilating the CopterSonde observations more accurately predict the evolution of the Rolling Fork tornadic supercell and its shape, intensity, location, and associated low-level updraft helicity (UH). Assimilating those observations more realistically represented the extent of low-level moisture advection and the strength of horizontal winds as they evolve throughout the observation period, thus limiting northward and westward displacement and better locating the most intense parts of the supercell. Even with the limited dataset, the CopterSonde UAS observations show promise in analyzing the storm environment and predicting the probability of severe thunderstorms with higher accuracy in the model. However, while the results from this single case study with only three profiling sites give us glimmers of hope, the results cannot be generalized. More studies need to be performed to assess the robustness of these results by assimilating a network of UAS BL measurements over a diverse set of cases in a convective-scale ensemble DA and prediction system.Item Open Access Evolution and Taxonomy of the Dryadoideae(2024-08-01) Monaghan, Leann; Moore, Abigail; Lupia, Richard; Souza, LaraDryadoideae is one of three subfamilies within Rosaceae (the rose family) whose genera largely preside in the western part of North America. It contains mountain mahogany (Cercocarpus), mountain misery (Chamaebatia), cliff-rose (Purshia), and mountain avens (Dryas); many of these taxa house nitrogen-fixing bacteria belonging to the genus Frankia. There is also a long fossil record of these plants dating back to the Tertiary period. Morphological variation within Cercocarpus is of particular interest due to the presence of many high-quality leaf fossils. The precise relationships among and within the genera within Dryadoideae are not well-understood due to limitations in previous genetic data used and their conflicting phylogenetic hypotheses. The aim of this study is to resolve phylogenetic relationships within the subfamily, with an emphasis on Cercocarpus and Purshia, using hundreds of highly conserved and low-copy nuclear loci through target-capture (HybSeq) sequencing using the Angiosperm 353 baits and to morphologically compare leaves of extant and extinct species of Cercocarpus. Overall, in both genetic and morphological analyses, C. mojadensis and C. pringlei are most closely related. The subfamily Dryadoideae is strongly supported, and Purshia, Cercocarpus, and Chamaebatia were monophyletic. More data is needed to parse out how exactly the species in both Cercocarpus and Purshia are related. The morphological analyses offer some insight on how the Cercocarpus species relate to each other morphologically but would benefit from increased sampling.Item Open Access INFLUENCE OF FREESTREAM REYNOLDS NUMBER ON UNSTEADY REFLECTED NORMAL SHOCKWAVE-BOUNDARY LAYER INTERACTIONS IN SHOCK TUBE EXPERIMENTS(2024-08-01) Bicak, Adam; Ozawa, Hiroshi; Parthasarathy, Ramkumar; Vedula, PrakashShockwaves can sharply increase the temperature and pressure of a gas in a reliable and near-instantaneous manner, leading to their utility of producing desirable conditions for the study of chemical combustion and high-speed gas dynamics. Shock tubes effectively produce regions of high-pressure, high-temperature gas by generating shockwaves that reflect off of the end of the driven section and form a reflected shockwave. Though the flow conditions after this sequence are typically assumed to be steady, phenomena such as the growth and interaction of the boundary layer with the reflected shockwave cause non-ideal fluctuations in these parameters. The effect of the Reynolds number of the flow behind the incident shockwave on these flow phenomena was studied using a newly built test section added to the shock tube facility of the High-Speed Aerothermodynamics Laboratory at the University of Oklahoma. High-speed schlieren imaging and pointwise pressure measurements were used to assess the reflected normal shockwave/boundary layer interaction (SBLI) and pressure fluctuations present in the flow. It was found that increasing the freestream Reynolds number helped decrease the size of the shockwave bifurcation formed from the SBLI while also reducing the amount of pressure fluctuations in the region behind the reflected shockwave. These trends persisted across experiments performed at three distinct shock Mach numbers.Item Open Access Synthesis of Folic Acid Conjugated Graphene Quantum Dot-Hexagonal Boron Nitride Nanocomposites for Targeted Cancer Cell Detection(2024-08-01) Nelson, Serana; Rouf, Tahrima; Wilhelm, Stefan; Tang, QinggongThe field of nanomedicine has evolved exponentially over the last decade with the development of new imagining modalities, nanoparticle types, and drug delivery systems aimed at treating and diagnosing cancer. Unfortunately, the paradigm for cancer diagnosis and treatment remains incomplete; there is a need for versatile and modular nanomaterials that act as contrast agents for the detection and characterization of pathologies. In this study, folic acid-conjugated graphene quantum dot-hexagonal boron nitride nanocomposites (FA-GQBNs) were synthesized for use as surface enhanced Raman spectroscopy (SERS) labels. Raman spectroscopy is a robust, label-free, spectroscopic technique that provides a molecular fingerprint and is commonly used for identifying unknown samples or compounds. Graphene quantum dots (GQDs) were synthesized from rice and bonded to hexagonal boron nitride (HBN) through electrostatic interactions. Next, graphene quantum dot-hexagonal boron nitride nanocomposites (GQBNs) are efficiently, inexpensively, and quickly synthesized using a bottom-up green synthesis strategy. Finally, to specifically and selectively target the folate receptor overexpressed on breast and gynecological cancer cells, folic acid (FA) was precisely conjugated to GQBNs to form FA-GQBNs. The synthesized nanocomposites were characterized using SEM, TEM, DLS, UV-Vis spectroscopy, FTIR, and Raman. The GQBNs were shown to increase cell proliferation by up to 36% when compared to the cell only group in cell viability assays while exhibiting superior optical and fluorescent properties and the FA-GQBNs were proven to be biocompatible. The FA-GQBNs were extensively characterized and their use as in vitro SERS labels as well as fluorescent labels explored. Understanding the properties and interactions of these nanocomposites provides a foundation for developing cancer therapeutics, drug delivery systems, wound-healing hydrogels, neurological treatments, and surface enhanced Raman spectroscopy nanoparticles that could be applied in the field of nanomedicine.Item Embargo Transient Brain-Wide Co-Activation Patterns in Infant Resting State Electroencephalography(2024-08-01) Nkurumeh, KC; Ding, Lei; Javier, Jo; Khanmohammadi, SinaThis study investigates the temporal brain dynamics in resting-state infant electroencephalography (EEG) by utilizing cortical co-activation patterns (cCAPs). Analyzing data from 49 infants in a longitudinal study, k-means clustering was applied on source level EEG data to reveal cCAPs which had short-lived lifetimes, recurrent and structured transitions, and unique spatial arrangements. These cCAPs described spontaneous brain activity as transitions between states of increasing levels of whole-brain activation. Additionally, the temporal dynamics revealed that the cCAPs representing states of high activation (whole-brain activity above the mean level of activation) were rare, whereas cCAPs representing brain states below the mean level of activation persisted for the majority of the time. Linear mixed effect models (LMEs) were used to examine the effect of infant age. In response to increasing infant age, the occurrence rate increased while the lifetime and normalized magnitude of activation decreased. Interestingly, the high activation cCAPs started off as rare events yet as age increased their occurrence became more common. The temporal and transitional characteristics of identified cCAPs in this study mirror prior results found in adults, indicating, firstly, a developmental continuity in brain activity organization from infancy to adulthood and, secondly, the ability of cCAP-based analysis to detect such continuities. The consistency of these findings across adult and infant age groups and their sensitivity to differences in infant age may prove useful in understanding neurodevelopmental trajectories and identifying biomarkers of typical and atypical infant neuropsychological development.Item Embargo THE IMPACT OF THE LIGHTS OUT TEXAS ADVISORY CAMPAIGN ON NIGHT SKY BRIGHTNESS AND BIRD COLLISION FATALITIES(2024-08-01) Trankina, Grace; Kelly, Jeff; Horton, Kyle; Bridge, EliLight pollution caused by artificial light at night (ALAN) is accelerating across the globe. ALAN interferes with biological processes such as nocturnal bird migration in several ways including mortality through bird window collisions. Some cities have started light reduction advisory campaigns during migration seasons to combat the adverse effects of ALAN on birds, but there has yet to be quantification of sky brightness reduction during these advisories. For chapter 1, I measured night sky brightness (NSB) in metro Dallas and Houston, Texas using Sky Quality Meters (SQMs) on 12 Lights Out, Texas advisory participant building rooftops to document the efficacy of the program. Though I found these cities are brightly lit compared to their rural counterparts, I did not find significant difference in light pollution reduction during the advisory. In chapter 2, I address if changes in regional night sky brightness impact the number of nightly fatalities documented. I present generalized linear mixed models assessing nightly nocturnal fatalities in the cities of Dallas and Houston during the 2022-2023 Lights Out, Texas monitoring season as compared to regional migration traffic rate and local atmospheric conditions including weather, lunar, and night sky brightness (NSB). Migration traffic rate has the strongest positive relationship with bird window fatalities across cities and seasons. Occasionally, weather variables that are conducive to bird migration in the spring and fall were also positively related to fatalities. Moon illumination percent was also consistently negatively associated with bird fatalities across cities and seasons. While these mechanisms are unclear, I hypothesize a more complex relationship between natural light, artificial light, and glass is at play. While NSB was not a significant variable in the models, the Lights Out, Texas campaign retains potential for effectiveness at the window scale. More research is needed on scales and complex interactions at which these variables influence bird mortality.Item Restricted (Re)-Placing the Music Salon(2024-08-01) Lunday, Breanna; Johnson, Jake; Yamane, Maxwell; Luong, VivianMusic salons have been a topic of interest amongst several fields of scholarship, including musicology, for many years. However, as these social gatherings move online due to the COVID-19 pandemic, I believe they are changing. In fact, both their characteristics and our relationships with music salons are changing. Due to these changes, we may not be able to recognize them where they have nestled themselves within the World Wide Web. This thesis aims to redefine our definitions of music salons and music salon culture by studying salons within the last 100 years that we might find “unusual.” These uncommon salon scenarios include the Deep Deuce neighborhood of Oklahoma City, Oklahoma, during the mid-1900s and the second wave of black metal music in early 1990s Norway. Exploring, becoming comfortable with, and embracing the unusual is a stepping stone in the journey of keeping up with today’s online salon culture.Item Open Access THE DEVELOPMENT OF A NEW KA-BAND NEAR-FIELD PLANAR MEASUREMENT SYSTEM FOR A DIGITAL PHASED ARRAY RADAR(2024-08-01) Moncada Calmet, Luis Felipe; Salazar Cerreño, Jorge Luis; Filley, Timothy; Zhang, YanA near-field planar scanner is an electromechanical system whose objective is to obtain the far-field pattern of a mostly directive antenna by recording its electromagnetic fields in the near-field region by taking measurements at different points on an imaginary finite plane in front of the antenna under test, the collected data are then mathematically processed to obtain the far-field patterns. Near-field planar scanners are an excellent solution to the various limitations involved in far-field measurement. This type of system does not require an extremely large anechoic chamber to avoid external and self-interference in a controlled environment and does not require the AUT to rotate or move in any direction, making this system ideal for measuring array antennas. Currently the use of array antennas is proliferating, so the need for affordable systems to test and calibrate them is essential. The objective of this thesis is to provide the design and assembly steps of a low-budget, customizable, open-source near-field planar scanner. This thesis discusses the mathematical equations and theoretical foundations of near-field planar scanners. It also explains our proposed hardware and software design, highlighting the most important considerations. This work also discusses the process to perform an antenna measurement using the present system taking advantage of all its capabilities and finally, this thesis presents the accuracy and correct operation of the proposed scanner.Item Open Access PRESERVICE MUSIC TEACHER PERCEPTIONS OF EXPERIENCES AND SELF-EFFICACY WITH MUSIC TECHNOLOGY IN OKLAHOMA(2024-08-01) Sellars, Maxwell; Pennello, Eric; Baumgartner, Christopher; Easter II, LonnieThe purpose of this quantitative study was to examine preservice music teachers’ perception of their experiences and self-efficacy with music technology in Oklahoma music teacher preparation programs. Specifically, I aimed to answer (a) what experiences preservice music teachers had with music technology during their undergraduate program, (b) the various ways that preservice music teachers were provided opportunities to explore the implementation of music technology in their coursework, field experiences, and student teaching, and (c) how efficacious preservice music teachers felt about utilizing music technology in their future classrooms. Preservice music teachers (N = 53) across multiple universities in Oklahoma were contacted to complete an online survey regarding music technology preparation, self-efficacy, and preservice music teachers' planned future implementation of music technology. Results from this study indicated differences among multiple variables regarding preparedness, confidence in future use, and self-efficacy regarding music technology opportunities and integration into their undergraduate coursework. Overall, preservice music teachers felt unprepared to teach using music technology post-graduation and lacked confidence in teaching music technology. However, preservice music teachers agreed their music technology skills increased after gaining professional teaching experience. Implications for music teacher preparation programs, music teacher educators, and inservice music teachers are discussed.Item Open Access Creating Grid-Based Machine Learning Severe Weather Guidance for Watch-to-Warning Lead Times in the Warn-on-Forecast System(2024-08-01) Varga, Samuel; Potvin, Corey; Homeyer, Cameron; Flora, Montgomery; Hill, AaronThe Warn-on-Forecast System (WoFS) is a rapidly updating convection-allowing ensemble focused on providing numerical guidance at watch-to-warning lead times (0-6 hours). Previous studies (e.g., Flora et al. 2021; Clark and Loken 2022) have incorporated machine learning (ML) to take advantage of the unique benefits of the WoFS and produce skillful guidance for severe weather hazards at lead times of 0-3 hours. This study evaluates the use of multiple ML architectures to produce 2-6 hour severe weather guidance using data from the WoFS. This represents the first use of machine learning to produce WoFS-based guidance at these lead times and the first use of deep learning to produce severe weather guidance using WoFS data. Predictors are created using WoFS forecasts from the 2018-2023 Hazardous Weather Testbed Spring Forecasting Experiments. Data from forecast hours 2 through 6 are processed into predictors of multiple scales, incorporating both storm and environmental fields. We utilize three ML architectures: logistic regression, histogram-based gradient boosting trees, and U-nets. These models are trained to predict severe wind, severe hail, tornadoes, or any-severe hazard during the 2-6 hour window. Target data comes from the NOAA Storm Events database. The four-hour ML guidance is compared to rigorous baselines consisting of optimized Neighborhood Maximum Ensemble Probabilities for each hazard. All ML methods evaluated outperform the NMEP baselines with tree-based methods achieving the highest performance of the traditional architectures. The largest improvement occurs for severe wind, followed by severe hail, tornado, and any-severe. Feature ablation shows that skill primarily comes from the intrastorm predictors and that the inclusion of multi-scale features exhibits little effect on skill. Despite the inclusion of additional features, the U-nets are unable to surpass the skill of the tree-based architectures. Similar to prior studies, this work shows the benefits of using the WoFS and ML to produce skillful guidance during the watch-to-warning period.Item Open Access An Examination of the Behavior of a Giant Hail-Producing Supercell in Oklahoma on 23 May 2011 Using Data from Five Doppler Radars(2024-08-01) Swinney, Leah; Bluestein, Howard; Snyder, Jeffrey; Bodine, DavidDual-polarization radar observations are valuable for identifying the location and evolution of hail in supercells. This study presents an analysis of a supercell that produced remarkably large hail [6 inches (15.24 cm) in diameter, setting a state record for Oklahoma at the time] on 23 May 2011 in the southwestern part of the state. This analysis uses data from three X-band, ground-based, mobile Doppler radars – RaXPol, MWR-05XP, and NOXP – each positioned generally to the southeast of the storm’s updraft in close proximity to each other, in addition to observations from two WSR-88Ds, KFDR located in Frederick, Oklahoma and KOUN located in Norman, Oklahoma. Of the five radars, all but the MWR-05XP and KFDR had polarimetric capabilities; the MWR-05XP, however, had rapid-scan, hybrid, phased-array technology. The investigation provides an in-depth examination of the storm's evolution, combining data analyses from all three mobile radars and the two stationary WSR-88D radars. The results of polarimetric variable comparisons, multi-Doppler wind analyses, and dual-frequency analyses will be presented. The main goal of this study is to contribute to an improved understanding of the transformation of hydrometeors, particularly hail, from their initial generation within the updraft to their eventual descent to the ground in a historic storm. A secondary goal is to document a failed attempt at tornadogenesis which was associated with a funnel cloud and examine why a tornado did not form.Item Open Access Activation of Interferon Through Glycated Chitosan Administration(2024-08-01) Unkel, Malayna; Chen, Wei; Acar, Handan; Tang, QinggongN-dihydrogalactochitosan (GC) is a novel immunoadjuvant with unique physiochemical properties that poses significant improvements upon its parent molecule, chitosan. Its potent immune stimulation properties make it promising in the world of vaccinations, with already proven reduction of morbidity in COVID studies. The key to generating immunity against intracellular pathogens is to generate a type I/II interferon (IFN) response. GC stimulates the desired IFN responses while other currently used adjuvants such as MF-59 often fail to do so. For comparison purposes, the immune response specific to GC stimulation needs to be understood. It has been previously demonstrated that application of GC in combination with photothermal therapy reduces mortality in cancer treatment studies. Furthermore, intranasal application of GC in combination with recombinant viral proteins has reduced COVID-19 mortality in mice. The fundamental question remains: Is GC acting as a physical barrier, or is GC stimulating a local type I IFN response which in turn activates antiviral pathways in the respiratory epithelium? Building on previously found GC immune activations, now presented are the results of gene activation and interferon activation in in vivo studies over time. This provides insight into the specific mechanisms by which GC succeeds at inducing anti-tumor and anti-viral immunological responses.Item Open Access Diurnal Effects of Exercise on Markers of Muscle Damage in College-Age Healthy Individuals(2024-08-02) Khurelbaatar, Chinguun; Black, Christopher; Pincu, Yair; Larson, RebeccaThe primary aim of this study was to examine differences in muscle damage markers (maximal voluntary isometric contraction, range of motion, soreness, swelling, thickness, urinary titin) between a morning group and an evening group. A secondary aim was to determine a correlation between pre-exercise urinary titin concentrations and performance metrics of muscle damage, serving as a predictor of muscle damage. 28 participants were recruited and randomized into two groups (14 each). Participants either arrived at 7:00 am or 5:00 pm and were instructed to perform 3 sets of 10 eccentric bicep curls at 120% of their established one repetition concentric maximum. MVC was assessed before and after to ensure a 40% decline. ROM, DOMS, swelling, and thickness were assessed before and immediately post-exercise. Performance metrics of muscle damage were assessed, 24, 48, 72 and 96-hours post exercise, and urinary titin was measured 96 hours post-exercise to capture peak concentrations. The primary findings were that time of day did not affect the degree of muscle damage, nor baseline measures of pre-exercise urinary titin. Although post-exercise urinary titin concentrations could not be quantified due to extremely high concentrations that exceeded the assay’s top limit of detection, it is clear that the muscle damaging protocol utilized in this project resulted in exaggerated urinary titin response. In the future, we plan to further explore the urinary titin response to damaging exercise and the potential diurnal variations in this response.