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Item Healthcare professionals and vaccine hesitancy: Approaches and barriers to discussions with patients(2024-07) Bolte, KristenVaccination remains the best way to protect against severe complications of the flu. However, hesitation towards flu vaccines is rising. This study explores healthcare providers perspectives on flu vaccine hesitancy, approaches to conversations about flu vaccines, and barriers they face when having conversations with flu vaccine hesitant patients. To conduct this research, a survey was sent out to various healthcare professionals asking about their experiences with flu vaccine hesitancy in their practice. 18 healthcare providers completed the survey. The findings showed that common approaches healthcare professionals utilize in their practice to address flu vaccine hesitancy include listening, providing patients with evidence, and respecting patients viewpoints. The findings also suggested that barriers to addressing flu vaccine hesitancy in the healthcare providers practice include limited health literacy, patient’s mind being made up before having a conversation with the provider, and a lack of time to hold conversations and address patient questions and concerns. The findings of this study implicate the need for patient-centered healthcare to improve patient/provider relationships and increase the amount of time providers are allowed to spend with their patients to address any patient questions and concerns about the flu vaccine and improve patient’s knowledge regarding flu vaccines.Item Biocontrol strategies to reduce foodborne pathogens in the food industry(2024-07) Bule, PunyaShiga-toxigenic Escherichia coli (STEC) O157:H7, and the big six non-O157 E. coli serogroups (O26, O45, O103, O111, O121, and O145) are the most significant foodborne pathogens, commensal to food animal gastrointestinal (GI) tract, and shed in their feces. They are responsible for numerous foodborne illnesses throughout the world. Similarly, Listeria monocytogenes is another pathogen that is a great threat to human health. The most common illness caused by Listeria monocytogenes is listeriosis. The foods that are commonly associated with the contamination of Listeria monocytogenes are Ready-to-Eat food products such as deli meats, hotdogs, and soft cheeses. Several antimicrobials have been used to resolve this problem; however, the issue of antimicrobial resistance (AMR) has arisen, and several natural biocontrol agents have been sought. One such alternative is the use of bacteriophages, which have garnered significant attention in the last two decades in reducing these major foodborne pathogens in the gut of animals as well as on food products. This study evaluates the efficacy of bacteriophages in correcting and preventing the attachment of E. coli to intestinal Caco-2 cells as well as their application on deli meat in reducing the contamination of Listeria monocytogenes. Specific bacteriophages targeting seven STEC serotypes were tested individually and in cocktails for both corrective and preventive treatments. Preventive treatments involved adding the phages before STEC inoculation, whereas corrective treatment involved adding phages after STEC inoculation and attachment to the cells. The results of this study indicated that preventive treatments were more effective than corrective treatments and cocktails are more effective in reducing STEC populations (almost undetectable) than the application of individual phage. Additionally, bacteriophages specific to Listeria monocytogenes were isolated from several environmental samples and were applied as preventive and corrective treatments on deli meat (ham). Similar to the intestinal cell study, the results of this study also showed that preventive treatments were better in reducing Listeria monocytogenes (P<0.05) on deli meat than corrective treatment. The findings of both studies suggested that bacteriophages could be used to reduce foodborne pathogens in both intestinal cells as well as on food products.Item Effects of culturally relevant design in virtual environments on Indigenous language learning(2024-07) Bazhaw Hyscher, AnnaThis study explores the relationship between Indigenous language acquisition and culturally relevant virtual learning environments. Utilizing a modified Stimulus-Organism-Response framework, the research compares the impact of culturally relevant and non-culturally relevant virtual environments on cognitive load, emotional responses, and language learning efficacy. Sixty participants experienced one of two virtual environments while learning vocabulary in Bodwéwadmimwen (the Potawatomi language). Data was collected through language assessments and surveys evaluating cognitive load, sense of presence, and emotional states (pleasure, arousal, and dominance). Results indicate that CRD environments significantly enhance emotional engagement, with participants reporting higher levels of pleasure and arousal compared to those in non-CRD settings. These emotional responses are crucial in fostering participants' willingness to engage with the learning environment, thus potentially improving language acquisition outcomes. However, no significant difference in cognitive load was observed between CRD and non-CRD environments, suggesting that the design's cultural relevance does not adversely impact the mental effort required for learning. The study's findings highlight the importance of incorporating cultural relevance in virtual learning environments to support Indigenous language preservation. By enhancing emotional engagement through culturally relevant design, these environments offer a promising approach to creating more effective and engaging educational experiences. The implications extend to the design of virtual reality-based educational tools, emphasizing the need for culturally sensitive approaches in developing instructional materials for endangered languages. This research underscores the importance of culturally relevant design in virtual learning environments and its potential to support Indigenous language preservation. By enhancing emotional engagement, these environments may offer more effective and engaging educational experiences. The study provides insights for future research and practical applications in the development of culturally sensitive educational tools and environments.Item Climatic challenges and adaptive behaviors: Analyzing the influence of temperature on movement and site selection in cattle and goats under pyric herbivory(2024-07) Budhathoki, SanchitaThe rangelands of the Southern Great Plains hold significant importance in the region's economy, agriculture, and conservation efforts. However, these rangelands are increasingly impacted by changing climatic conditions, which affect both the ecosystem and the animals that depend on it. Understanding the adaptive behaviors of livestock in response to these climatic changes is crucial for developing sustainable rangeland management practices. Our study aimed to (i) analyze the influence of weather parameters (air temperature and relative humidity) and species type on movement patterns of cattle and goats and (ii) assess how variations in air temperature alter the site selection behavior of these animals. We utilized GPS-telemetry data collected from thirteen cattle and nine goats during the growing season (April to September) from 2020 to 2022. Generalized additive mixed models (GAMMs) were employed, and Akaike Information Criterion (AICc) was used to select the best-fit model. The interaction between air temperature, relative humidity, and species type was the most significant predictor of movement distance (adjusted R² = 0.086). Notably, air temperature emerged as the primary factor influencing the distance moved, surpassing all other measured parameters. Results from resource selection function analysis revealed that time since fire significantly influenced site selection for both species compared to the other environmental variables we examined, with significant negative coefficients (-0.148 for cattle, p < 0.05; -0.089 for goats, p < 0.05). Both cattle and goats preferred woody vegetation and water sources as temperatures increased, with cattle showing a preference for shaded areas at approximately 28°C and goats at around 40°C. These findings emphasize the necessity for adaptive rangeland management strategies that account for species-specific thermoregulatory behaviors and incorporate fire regimes to bolster ecosystem resilience. The insights obtained from this study are instrumental in formulating sustainable rangeland management practices to address the challenges posed by changing climatic conditions, thereby ensuring the conservation and productivity of these vital ecosystems.Item Understanding the effects of warming on nitrogen cycling dynamics in a tropical forest(2024-07) Bartz, Parker M.Tropical forests have an exceptional capacity to sequester carbon, support biodiversity, and cycle nutrients. Ample soil nitrogen (N) in these forests allows high rates of primary production and rapid regeneration. Nitrogen is regulated by microbial communities, which can be free-living in the soil and leaf litter (asymbiotic) or in symbioses with certain trees. Climate warming is predicted to increase microbial N fixation and may alter the growth of N-fixing trees, which are major N inputs in tropical forests. To investigate the effects of warming on both the asymbiotic and symbiotic components of the N cycle in tropical forests, we analyzed soil and leaf litter samples as well as annual seedling census data from a warming field experiment in Puerto Rico. Amplicon sequencing of the 16S and nifH regions of our samples revealed that microbial community composition was significantly altered by warming. We found that asymbiotic N fixation rates were increased under warming, and this increase in fixation was partially mediated by the change in the N-fixing bacterial community, at least in the leaf litter. Nitrogen-fixing seedlings exhibited a higher growth rate than non-fixers under warming, and this growth advantage was absent under ambient conditions. The growth of N fixers was reduced by a higher proportion of neighboring N fixers, but this competitive effect was only significant under warming. Finally, seedling growth increased following hurricane disturbance before significantly decreasing, possibly because a flux of growth-supporting light and nutrients after the hurricane quickly dissipated. This growth increase and subsequent decrease was significantly exaggerated in N fixers under ambient conditions. These results tentatively indicate that the anticipated increase in N fixation under warming confers N fixers a growth advantage that alters neighborhood growth dynamics and growth response to hurricane disturbance. These effects of warming on both asymbiotic and symbiotic N fixers suggest that warming increases N flux from the atmosphere into this tropical forest, but it remains unclear how the other components of the N cycle are altered, including N mineralization. Future research should aim at understanding how climate change influences the full N cycle in tropical forests.Item From startup to stability in rural counties: An assessment of support organizations’ impact on small business creation and maturation(2024-07) Wynne, GaryA significant amount of research has demonstrated the importance of entrepreneurship for economic and community development in rural areas. Less established is what type of local support organizations can foster the birth and growth of these small businesses. Another unanswered question is whether the relationship between business outcomes and support organizations is similar between rural and urban locations. We test the general hypothesis that more local support organizations leads to higher business births and maturation (i.e. growing to a "Stage 2" business of 10+ employees) using panel data for all U.S. counties from 2015-2023. The dependent variables are aggregate 2-digit NAICS births for each county-year, and the independent variables of interest are 5 distinct 4-digit NAICS categories including religious organizations, grantmaking / giving services, social advocacy organizations, civic and social organizations, and business / professional organizations. The data comes from the Business Dynamics Research Consortium at Wisconsin and is compiled from Data Axle (which follows millions of U.S. businesses over time). Fixed effect panel Poisson models estimate the impact of the 5 distinct support organizations on births and maturation. These models include county and year fixed effects and control for the number of businesses started (in the same sector and overall) in the prior year as well as education, income, unemployment, and broadband adoption rates. The results show that some support organizations (grantmaking services, civic organizations) have positive impacts while others (religious, social advocacy) are typically negative. There are meaningful differences in results across metro, non-metro and "very rural" counties.Item Use of novel entomopathogenic Metarhizium strains for control of fall armyworm (Spodoptera frugiperda) in turfgrass(2024-07) Singla, RashmiEntomopathogenic fungi offer promising and environmentally friendly alternatives to chemical insecticides for pest management in turfgrasses. Commercialized entomopathogenic fungi registered for application to turfgrasses primarily use Beauveria bassiana GHA (Botanigard) or Metarhrizium brunneum F52 (Met52) as the active agents. Strain adaptation to local environments could improve the efficacy of biological control organisms. So, in 2014, 37 novel strains of entomopathogenic fungi were isolated from the soils of several horticultural sites in Oklahoma and assayed for virulence against waxworms and mealworms. The five most virulent strains which included four strains of M. robertsii (OK78, OK87, OK106A, and OK205) and one strain of M. lepidiotae (OK102) were selected for laboratory bioassays and field trials against black cutworm (Agrotis ipsilon), a turfgrass-defoliating caterpillar pest. In both laboratory bioassays and field trials these fungal strains caused high mortality (82.6%-to-90.6%) to black cutworms. Based on these results, the efficacy of each fungal strain against another turf pest, fall armyworm (FAW) (Spodoptera frugiperda) larvae, was assessed in laboratory bioassays and field trials. In 6 cm diameter laboratory bioassay cups, second instar FAW larvae (n=25 per treatment) were co-incubated with 1 g negative control sterile proso millet grains or sterile proso millet grains inoculated with each of the five native Metarhizium strains or with positive control M. brunneum F52. Mortality was assessed at 2-, 4-, 6-, and 8-days after-treatment (DAT). In field trials, screened, 46 cm diameter PVC corrals (n = 4 plots per treatment) on ‘Tyee’ bentgrass putting greens (OSU Turfgrass Research Center, Stillwater, OK) infested with 25 FAW eggs and inoculated with 10 g proso millet grains inoculum of each fungus or sterile proso millet seed control. One day prior, 4 plots were treated with bifenthrin (Talstar P at 0.2 fl. oz. per 1,000 sq. ft.). After 14 days, larval mortality (%) and turf damage ratings were evaluated. A high rate of mortality was observed in FAW larvae both in laboratory bioassays and field trials. The next objective of this study was to calculate LC50 (Lethal Concentration 50%), Mortality data were analyzed using probit analysis to determine the effective range of spore suspension concentrations per application for each strain. The LC50 values were as follows: OK78 - 4.2 x 10^5 conidia/mL, OK87 - 1.74 x 10^5 conidia/mL, OK102 - 2.82 x 10^5 conidia/mL OK106A - 6.31 x 10^5 conidia/mL, and OK205 - 3.63 x 10^5 conidia/mL. This study showcases the promising potential of these novel Metarhizium strains as effective biopesticides in turfgrass pest management.Item Foamability properties of low GWP refrigerant and oil mixtures(2024-07) Shepard, Kyle AllenOil-refrigerant mixture foaming is common in compressors found in many HVAC systems. Low-GWP refrigerants, particularly HFOs and blends, have under-studied foaming behavior and characterizing and understanding foaming behavior is necessary for the integration of new refrigerants in vapor compression cycles. In this work, an apparatus is designed and fabricated to study oil-refrigerant pairs in three manners: 1) physical foaming characterization, 2) measurement of dynamic surface tension between oil-refrigerant media, and 3) measurement of oil-refrigerant solubility data. Foaming is generated through pressure drop by charging and heating a chamber of refrigerant and oil and rapidly connecting it to a low-pressure chamber. Dynamic surface tension data is measured in post-processing via maximum bubble pressure tensiometry (MBPT). Foaming and dynamic surface tension experiments are visually recorded with a custom made, high-pressure sight glass which utilizes pressurized water to attain higher internal oil-refrigerant pressures. Physical characterization of foaming and bubbles is carried out in post-processing with camera-tracking software. Solubility is experimentally determined with a circulation loop containing a viscometer and a densitometer and thermodynamic correlations. The completed apparatus will be used to characterize the behavior of 11 pairs of refrigerant-lubricants including various viscosity grades of mineral oil, POE, PAG, and PVE lubricants paired with HFC and HFO refrigerants.Item Modeling recurrent turbidity impairments in Oklahoma and the impact of targeted best management practices on sediment concentrations(2024-07) Winrich, AbigailThe Clean Water Act mandates that states must maintain a water quality standard to ensure surface waters remain functional for aquatic life and safe for agricultural or recreation use. Water Bodies that exceed any of the defined standards must be reported as threatened or impaired semiannually to the USEPA per section 303(d). If listed, states must then develop and implement a watershed plan for the threatened or impaired waterbodies to reduce pollution and hopefully delist the waterbody. While the waterbody is impaired, states have access to funds set aside by Section 319 that provide funding for monitoring efforts and technical assistance and cost sharing for landowners. Management of non-point source pollution, such as turbidity, is achieved by implementing best management practices (BMPs), which are costly to install and maintain, making it imperative that they provide a lasting reduction in pollution. Turbidity is a leading impairment that largely stems from non-point source pollution, which are sources without easily identifiable outlets. This research analyzed Oklahoma’s 303(d) lists from 2002-2022 for recurrent turbidity impairments. Three case study watersheds were selected to determine potential causes for the list-delist-relist pattern. The Wewoka, Turkey, and Stillwater Creek watersheds were selected based on size, ecoregion, and documented management efforts. The watersheds were then modeled for the 21-year period using the Hydrologic and Water Quality System (OK.HAWQS). A baseline model was run to analyze historic sediment contributions in each watershed, which allowed us to investigate the impact of different land use types on sediment loss and find variations across watersheds in erodibility. The Grassland, Winter Wheat, and Pasture land uses in the Stillwater, Turkey, and Wewoka watersheds lost the most sediment, respectively. BMP scenarios were run for the land use contributing the most sediment in each watershed. Based on the most commonly implemented practices in Oklahoma, we chose enclosure fencing, conservation grazing, and no-till for Stillwater, Turkey, and Wewoka, respectively. These scenarios showed conservation grazing has a positive impact on sediment reduction, up to 50%, while no-till and fencing had a small to neutral impact on sediment loading. These results can be used to inform future management project ad assess the adequacy of current management techniques in a changing climate.Item Framing rural realities: Exploring youth perspectives of rural communities through photovoice(2024-07) Sewell, JaelynAround 60 million people, or one in five Americans call rural America home (Ratcliffe et al., 2016). Youth should be perceived as “the main pillar of any society” (Kushawa et al., 2022, p. 978). Therefore, investing in them, their leadership, and perspectives might improve vitality for rural communities’ long term. To better understand youth’s perceptions of their rural community, 15 secondary agricultural education students living in a rural, farm-dependent community were recruited to participate in a photovoice study. This study assessed the strengths, weaknesses, challenges, opportunities, and uniqueness of their communities. Data was collected through photographs, captions, a focus group with youth participants, and a one-on-one interview with the agricultural educator who helped facilitate the study. Transcripts were analyzed using Glaser’s constant comparative method (1965). The focus group data were analyzed using a combination of the Critical Consciousness Theory and the Community Capitals Framework (Emery & Flora, 2020). Findings revealed students were largely positive regarding their perceptions of their hometown. They described their hometown as a farming, agriculturally based community and appreciated the availability of educational opportunities. Weaknesses included issues with infrastructure like poor road conditions, dilapidated downtown builds, and abandoned homes. Although weaknesses were identified by students, they often saw opportunities in those weaknesses for improving their community. Students felt empowered to make changes in their community after participating in the photovoice study.Item Dynamic phasor-based framework for accelerated power system simulation via adaptive time stepping(2024-07) Ali, AhmadTransient analysis is essential for understanding the behavior of power systems under various contingencies. However, due to the size and complexity of power systems, coupled with their wide timescale dynamics, detailed transient analysis is often computationally prohibitive. Consequently, simplified device models are typically used for large-scale analysis.This thesis investigates the potential of dynamic phasor (DP) based modeling to accelerate simulation speeds while retaining detailed models. Various DP formulations exist in the literature, and this work aims to consolidate these methods and revisit the theoretical foundations of DP-based schemes. To accelerate transient analysis, we combine DP-based modeling with adaptive time-stepping in numerical integration. This approach achieves a computationally efficient simulation framework without losing detail while maintaining high numerical accuracy. Our analysis demonstrates that DP-based modeling can achieve varying levels of detail in simulations without requiring model-level modifications. To explore this framework, a simulation platform using the Julia programming language is developed. Numerical issues impacting the computational stability of the simulation are identified, and remedial strategies are presented. A validation case study using the single-machine infinite-bus system is conducted, with results compared to the electromagnetic transient simulation tool PSCAD and quasi-steady-state (QSS) simulation tool ANDES. An additional case study using the IEEE-14 bus system is performed. The results indicate that DP-based modeling achieves computational speeds comparable to QSS simulation tools, with highly accurate simulation results. This suggests that detailed information about system trajectories can be obtained using DP-based modeling framework with equal or less computational effort as compared to QSS simulation.Item Variation in external ear and head morphology of preserved North American deer mice (genus Peromyscus) and implications for auditory function(2024-07) Sergott, Casey ElizabethAn animal’s external head morphology is the starting point of auditory communication by receiving sounds from the environment and plays an especially important role in how an animal perceives and localizes sounds. Particularly, the presence of the external ear structure, or pinna, is essential to front/back and vertical discrimination of acoustic signals. The process of accurately perceiving the location of acoustic signals is not only reliant on morphology but also on deeper processing at the brainstem level. For the brain to assess the approximate location of a sound, it relies on the computation of two cues: interaural time differences (ITDs), which can be defined as the shift in arrival time of a particular sound at each of the pinnae, and interaural level differences (ILDs), or the shift in sound level of a particular sound at each of the pinnae (i.e., sounds coming from the left side of an individual are going to be perceived slightly quicker and as slightly louder at the left ear versus the right ear). Therefore, it is assumed that significant variability in head and pinna size and shape will also cause significant variability in the detection of acoustic signals. In this study, we focus on identifying differences in external head and pinna morphology in six species of North American deer mice (genus Peromyscus) to determine if there are differences in head morphology based on species distribution differences. We measured the dimensions of the head and pinna of over 1,200 preserved specimens of P. boylii, P. californicus, P. gossypinus, P. leucopus, P. maniculatus, and P. truei, followed by a series of head-related transfer functions (HRTFs) on several individuals to study the relationship between morphology and auditory function. Our results show the greatest variability in inter-pinna distance and pinna width across the six species with similar ITDs and ILDs, suggesting that differences in morphology may be more related to discriminating elevation of sounds, not differences in horizontal sound discrimination. Not only will this study contribute to existing research on external morphology and auditory function, but it will also provide invaluable insight into the use of preserved specimens in auditory research, an area that is currently understudied.Item Centipede nets improve fish sampling efficiency and reveal unseen diversity in a tropical eastern Pacific mangrove(2024-07) Scholten, Tanner EliDespite the broadly held view that mangrove forests provide crucial habitat to many species, including juvenile fishes, the lack of efficient methods for sampling within the complex structure of mangrove prop roots and pneumatophores has hampered our ability to study mangrove fishes, especially in turbid areas where visual sampling is not an option. Many studies of mangrove fish communities rely on the assumption that species captured in adjacent mudflats and open channels are also present within vegetated microhabitats. I conducted a multi-season study at six mangrove sites in the Gulf of Nicoya, Costa Rica to compare the performance of traditional fishing gears used in mangroves (cast nets and seines) with that of the centipede net—a commercial fishing technique used in mangrove areas in the South China Sea. Centipede nets captured more species and more unique species, and they had greater sample coverage than traditional gears. Sampling with centipede nets in combination with either cast nets or seines captured more species in fewer site visits than a conventional sampling regime using cast nets and seines. Sampling with all three gears yielded the highest estimates of true species richness, Shannon diversity, and Simpson diversity. Centipede nets performed well across a range of environmental conditions, but catch rates were negatively related to bank steepness, so samples may not be comparable across sites with extremely different steepness. The proportion of species caught exclusively in centipede nets was lower in the Gulf of Nicoya (22%) than in Dongzhai Harbor, China (32%), but this difference was likely driven by differences in study design. I recommend the use of centipede nets, whether in isolation or in combination with traditional techniques, to researchers seeking a comprehensive understanding of fish communities utilizing flooded mangrove habitats to guide effective conservation and management strategies.Item Village evacuated: Community impacts of the East Palestine, Ohio Train Derailment(2024-07) Scott, MadisonOn February 3rd of 2023, a Norfolk Southern train derailed in the town of East Palestine, Ohio, exposing residents to both smoke from the ensuing fires and the toxic chemicals being transported via railcar. Due to its small-town qualities and the prevalence of extended family histories within the town, East Palestine has become a fascinating case study of what happens when environmental dangers become omnipresent in a space to which people are deeply attached. To examine this, 24 interviews were conducted with residents of East Palestine and the nearby township of Darlington Pennsylvania, first responders, and activists involved in the community. To guide those conversations and analyze interview data, theories such as place and space, critical environmental justice, recreancy, and contested illness were utilized to provide a frame through which we look at the personal experiences of a variety of individuals who lived through the derailment, evacuation, and subsequent controlled burn. Using both inductive and deductive approaches, transcripts were coded into theoretical themes, and connections between those chosen theories were uncovered. Results demonstrate a myriad of both physical and mental health impacts, a community left divided, and the deterioration of trust in authority among community members who feel they have been left behind. The findings of these interviews not only draw a bleak picture of human experiences in the wake of industrial disaster, but also create a compelling argument for further exploration of this case and others with regards to how perpetrators are held responsible and how their actions deepen impacts felt by the communities they interact with in the long-term.Item Qualitative analysis of wellbeing among caregivers of children with incarcerated parents(2024-07) Russell, DiamondThis study investigates the experiences of caregivers of children with incarcerated parents, concentrating on the stressors, health outcomes, and coping mechanisms they encounter. Taking a qualitative approach with a 6-week support group, this research reveals an important view on the experiences of the participants outlined by the stress process model. The results in this study show that the caregivers within this population endure many challenges such as financial stress and stigma while also exhibiting significant resilience. Although this study had a small sample size and lacked in-depth demographic characteristics of the participants, it contributes to existing research by providing valuable insight about this unique caregiver population, emphasizing the need for support services, policy changes, and community awareness. This study emphasizes the vital role caregivers play and the significance of addressing their needs to assist in improving the outcomes of caregivers and the children/family they are caring for.Item Effects of planting date and variety on yield and quality of snap bean (Phaseolus vulgaris L.) in Oklahoma(2024-07) Richmond, Jessica M.Although numerous studies have evaluated snap bean (Phaseolus vulgaris L.) pod yield from once-over harvest systems and pod quality at progressing maturities in a given harvest season, few have evaluated yield and pod quality in different seasons of production within the same year and fewer still have evaluated yield and quality from pods harvested at the same pod maturity successively from the same plants. The aim of this study was to determine if snap bean yield or pod quality (pod color and sugar accumulation) differed between plants harvested multiple times in spring and fall planting seasons in north central Oklahoma. Nine snap bean cultivars, including seven green podded and two yellow podded cultivars, were chosen for field production in spring and fall production seasons of 2022 and 2023. Sequential harvest of pods from the same plants and at the same relative stage of pod development occurred weekly for a three week period. Pod yield, pod tristimulus color, and pod sugar concentration were measured. Total pod yield pooled across seasons and years was lower for ‘Sybaris’ at about 4,100 kg ha⁻¹ than for six of the other cultivars whose yield ranged from 7,000 to 8,600 kg ha⁻¹. While pod yield typically increased from 900 to 1,300 kg ha-1 in the first weekly harvest to 3,500 to 3,700 kg ha⁻¹ by the last weekly harvest in the spring season, during the fall season it either decreased in 2022 from 1,900 kg ha⁻¹ in the first weekly harvest to 690 kg ha⁻¹ by the last weekly harvest or remained the same in fall of 2023 at 2,600 to 3,000 kg ha⁻¹ at each weekly harvest, with the decrease in yield in fall, 2022 likely due to sub-optimal low temperatures during pod development. Tristimulus pod color differentiated yellow-podded from green-podded cultivars and while some differences in hue and chroma were evident within snap bean pod color groups, each cultivar maintained its color properties at each harvest across seasons and years of the study. We observed a decrease in total pod sugar concentration from the first to the last harvest from 145.5 to 107.2 mg gm⁻¹, for glucose from 48.4 to 33.0 mg gm⁻¹ and for fructose from 90.7 to 52.0 mg gm⁻¹. We also observed an apparent increase in sucrose concentration from 9.2 to 21.9 mg gm⁻¹ from the first to last pod harvest. Decreasing total and monomeric sugar concentrations, coupled with increasing sucrose concentration, have been documented for overmature snap bean pods which were deemed less desirable due to lower perceived sweetness. In terms of sugar concentration, later harvested snap bean pods in a successive harvest system, even though they were harvested at the same relative stage of maturity as earlier harvested pods, resembled over-mature pods from a once-over harvesting system, perhaps indicating that snap bean plant age influenced pod sugar concentration in a similar manner to pod age.Item Metabolic response of fire engine crew members during simulated fire task scenarios(2024-07) Perez, Rosie IbisFirefighters have a demanding and arduous job, where each task may put many lives at risk. To reduce this risk the National Fire Protection Association (NFPA) has a minimum standard of 12 METs or VO₂ of 42 ml/kg/min⁻¹ during a graded exercise test. The use of fire simulated scenarios is a way to replicate the tasks that firefighters face during their job and the associated metabolic demands in less harmful conditions. The purpose of the study was to determine the metabolic demands of fire engine crew members during fire simulated tasks. The following are major findings of the thesis. The average peak METs during Evolution A1 (pair) and Evolution A2 (crew) was 11.6 ± 2.9 and 10.9 ± 3.7. There was no difference in average peak METs or average peak VO₂ between evolution tasks (p > 0.05). The average peak METs for the individual tasks assessed ranged from 4.9 to 6.3 METs, and there was no significant difference between the individual tasks and average peak METs levels (p = 0.461) or between the individual tasks and average peak VO₂ (p = 0.525). There was no difference between the evolution scenarios METs to the NFPA minimum standard (p > 0.05). The METs achieved during the evolution tasks were consistent with the minimum standard of 12 METS recommended by the NFPA for injury reduction. The results of this study reinforce the necessity for adequate levels of aerobic fitness and the need to perform high intensity cardiovascular training when preparing firefighters to meet the metabolic demands of a fire scene.Item Effect of a phytogenic feed additive containing garlic, clove, and Capsicum oleoresin on the health and performance of newly-received, high-risk calves(2024-07) Owen, NatallyThis experiment assessed the effects of a phytogenic feed additive (PGA) containing garlic, clove, and Capsicum oleoresin on performance and health of high-risk, newly-received beef calves. Crossbred steers and bulls (n = 712; n = 371 steers; n = 341 bulls; initial body weight; BW = 239 ± 6.8 kg) were stratified by arrival sex and BW, then randomly allocated to experimental treatments (n = 9 pens per treatment; n = 24 to 29 calves per pen). Treatments included: 0 mg ⋅ steer⁻¹ ⋅ d⁻¹ of PGA (PGA0), 250 mg ⋅ steer ⁻¹ ⋅ d⁻¹ of PGA (PGA250), or 500 mg ⋅ steer⁻¹ ⋅ d⁻¹ of PGA (PGA500). No differences in BW existed throughout the experiment (P ≥ 0.20; PGA vs. PGA0 P ≥ 0.11). In the overall model, no differences (P ≥ 0.23) in ADG existed. However, when comparing calves receiving PGA to calves receiving PGA0, ADG tended to be greater in calves receiving PGA from d 0 to d 14 (P = 0.09). No differences in DMI existed throughout the experiment (P ≥ 0.27; PGA vs. PGA0 P ≥ 0.13). No differences in G:F existed between treatments (P ≥ 0.26), however when comparing calves receiving PGA to calves receiving PGA0, G:F tended to be greater in calves receiving PGA from d 0 through d 14 (P = 0.10). Steers receiving PGA500 were treated with an antimicrobial for bovine respiratory disease (BRD) less often than steers receiving PGA0, with PGA250 being intermediate. Steers receiving PGA were also treated once for BRD less often (P = 0.01) compared to steers receiving PGA0. The percentage of mortalities and the percentage of steers removed from the study were not different (P ≥ 0.16; PGA vs. PGA0 P ≥ 0.14); however, there tended to be more combined mortalities and removals for steers receiving PGA (P = 0.09). In summary, the reduction in antimicrobial treatments for BRD in cattle receiving PGA has the potential to reduce the overall use of antibiotics in beef production, but the impact of PGA on mortalities and removals needs investigated further.Item Analyzing the long-term trend of evaporative water loss at multi-purpose reservoirs in Oklahoma for sustainable water management(2024-07) Osei, KathyThis study examines the long-term trends of evaporative water losses at Lake Hefner and Canton Lake in Oklahoma from 1985 to 2018. Using a mixed-method approach, the research assesses annual and seasonal evaporation losses for both lakes and analyzes their correlation with various climatic factors. The findings reveal a statistically significant rise in evaporation rates, with Lake Hefner and Canton Lake experiencing annual increases of 0.31 mm and 0.42 mm, respectively. Notably, these increasing trends are more pronounced during the autumn and winter months, contrary to the expected summertime peaks. This unusual pattern is attributed to the thermal inertia of the lakes and the rising winter temperatures reported across the Western United States. The study further explores the profound impact of climate change, specifically the intensification of drought episodes in this region, such as those recorded in 2003, 2006, and 2011, which exacerbated evaporation rates. These findings underscore the increased vulnerability of water resources to climatic variability and the need for proactive solutions. In response, this thesis proposes adaptive management strategies within the framework of Integrated Water Resources Management (IWRM). It recommends the integration of evaporation suppression strategies into water management practices and the adoption of innovative technologies such as the application of wind-resistant monolayer films based on reservoir storage triggers. Policy recommendations are also discussed, emphasizing the need for robust measures that include regular evaporation monitoring and the use of financial incentives to adopt water-saving technologies. By addressing the localized impacts of climatic factors on evaporation and integrating these insights into reservoir management, this research contributes to the development of targeted strategies aimed at enhancing the sustainability of water resources in Oklahoma and similar environments globally.Item NASA’s FLDAs soil moisture data as an index for forage crop insurance and disaster protection programs(2024-07) Muyombo, Ephraim DibueDue to the difficulty of measuring forage yields, U.S. crop insurance and disaster programs targeted toward forage producers’ base payments on an index hoped to correlate with forage yields. This study explores using NASA’s soil moisture data, Famine Early Warning Systems Network Land Data Assimilation System (FLDAS), as a more accurate index for drought insurance and disaster programs compared to traditional indices like the United States Drought Monitor (USDM) and rainfall data as well as in-situ soil moisture data from the Oklahoma Mesonet. Correlation analysis revealed varying degrees of correlation between NASA’s volumetric water content (VWC) and Mesonet’s VWC and rainfall anomalies across different depths and regions. High correlations at 5 cm and 25cm depth were scattered around Oklahoma's central and western parts. Lower correlations were scattered in the eastern part of the state, urban areas, and vast irrigated regions. NASA’s VWC at 25 cm consistently showed the highest correlation with hay yield anomalies, particularly in June and July. Similarly, all variables showed their highest correlations during these critical months. Linear regression models reveal that NASA Fractional Available Water (FAW) (R² = 0.42), Mesonet FAW (R² = 0.41), NASA VWC at 5cm (R² = 0.44), NASA VWC at 25cm (R² = 0.45), USDM (R² = 0.29), and rainfall (R² = 0.31) soil moisture data are significant predictors of hay yield anomalies. Quadratic models explained up to 49% of the variance in yield anomalies. Mixed-effect models underscored the significance of NASA and Mesonet anomalies on hay yield, revealing strong relationships even when controlling for local environmental characteristics and annual weather patterns. Segmented regression models identified breakpoints in the soil moisture-yield relationship, highlighting the importance of non-linear effects in agricultural data analysis. Among all models, NASA FLDAS VWC at 25cm was consistently the best predictor. Incorporating NASA’s soil moisture data into crop insurance and disaster protection programs could improve financial support accuracy for farmers. Future research should validate these findings across diverse regions and assess the economic impacts of implementing this approach in insurance programs.