Open Research Oklahoma (Oklahoma State Univ.)
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Effects of eastern redcedar on prescribed fire and fire modeling in cross timbers forests
No full textEastern redcedar (Juniperus virginiana; ERC) has encroached into Cross Timbers forests, an ecotone historically dominated by post oak (Quercus stellata) and blackjack oak (Q. marilandica) and the transition from the eastern deciduous forest to the Great Plains. Since the early 20th century, less fire has caused shifts toward fire intolerant species, altering site conditions. ERC presence can result in increased fuel load and has become an important management focus. Cross Timbers forests historically relied on fire for continued oak dominance, so increased fuel loading due to ERC is pertinent for management. Mechanical treatment of large ERC is necessary since ERC is less susceptible to fire mortality at larger sizes. We performed a forest and fuels inventory followed by common mechanical treatments of ERC in Oklahoma Cross Timbers forests. We followed this with a prescribed burn to assess how forest, fuels, and ERC management conditions affect fire behavior. The presence of dead, dry ERC fuels resulted in increased flame lengths and more severe fire behavior while removal of ERC fuels lowered fire behavior. Untreated stands of ERC encroached Cross Timbers forests may have lower flame lengths and fire severity due to the loss of fine fuels associated with heavy ERC encroachment. ERC treatment affects fire behavior. Furthermore, there is a lack of studies on fire prediction in ERC encroached forests. Our fuels and prescribed fire weather conditions data were used to model simulated fire conditions in FlamMap and BehavePlus. A visually best match fuel model from Scott and Burgan (2005), a custom fuel model using our fuels data, and the currently used model to predict fire behavior in ERC encroached Cross Timbers forests were compared. Overall, fire programs performed poorly at predicting site specific flame lengths but in limited cases, fuel models could be associated with ERC treatment to predict fire behavior on average and at a landscape scale. ERC in Cross Timbers forests alter fire behavior, and depending on management goals, treatments can negatively affect fire behavior and forest structure. Fire modeling of fuel types incorporating ERC encroachment needs further development
Impact of plant growth regulators on freeze tolerance of bermudagrass and evaluation of new putting green-type bermudagrass genotypes
No full textThere is a demand to improve winter survivability and performance of putting green-type bermudagrass [Cynodon dactylon (L.) Pers.× Cynodon transvaalensis Burtt-Davy] in the U.S. transitional climatic zone. To address this challenge, three studies were conducted to evaluate the effect of plant growth regulators (PGR) on freeze tolerance and assess the performance of putting green type bermudagrasses developed by Oklahoma State University (OSU). In controlled-environment trials, paclobutrazol (PBZ; 0.52 kg a.i. ha⁻¹) significantly enhanced post-freeze recovery, viable rhizome dry weight, turf quality and chlorophyll content. Genotypic variation was evident, with OSU1629 and ‘Tahoma 31’ [OKC1131] exhibiting superior regrowth after exposure to -9°C to -11°C in one of the two experimental runs. A parallel study tested abscisic acid (ABA; 0.11 kg a.i. ha⁻¹) and prohexadione calcium (Pro-Ca; 0.64 kg a.i. ha⁻¹) on ‘TifEagle’ bermudagrass. The findings revealed that ABA combined with 4-week acclimation before the freeze test reduced LT50 (lethal temperature for 50% survival) by 3.5°C , accelerated recovery after -8°C exposure, and increased rhizome biomass. This study also indicates that sufficient acclimation periods are critical for maximizing freeze resilience. Concurrently, field evaluations of OSU’s experimental genotypes against standards (‘TifEagle’, ‘Tahoma 31’) highlighted 11×8 matched ‘TifEagle’ in ball roll distance and showed early green-up similar to the cold-hardy standard (‘Tahoma 31’). Although ‘TifEagle’ maintained the highest turf performance index (TPI), it was susceptible to winterkill. In contrast, the experimental genotype 11×8 demonstrated comparable or improved turf quality ratings, making it a competitive performer. Collectively, these findings indicate that the application of PGRs like PBZ and ABA with an adequate acclimation period may enhance winter resilience by increasing recovery rate and freeze stress adaptation. The identification of elite experimental genotypes like 11×8 expands genetic resources for cold-tolerant putting surfaces, offering actionable insights for turfgrass management and breeding programs in the regions where existing ultradwarf bermudagrass cultivars are susceptible to winterkill
Quantifying human behavior in hybrid automation systems using a stochastic approach
No full textThe use of hybrid autonomous systems has provides a breakthrough in the design of complex systems in several domains, as it highlights the strength of humans and automation in these systems. However, limited research has focused on developing hybrid autonomous systems, leading to longstanding automation-induced cognitive and performance issues observed in the realm of Human-Automation Interaction. To rectify this, it is imperative to understand the dynamics in task efficiency and human transition behavior within existing adaptive-automated systems. Additionally, modeling these human-automation dynamics via a stochastic approach is essential as it captures inherent human variability within autonomous systems.
Therefore, this research explores individual and contextual factors that influence interaction dynamics and performance variability and assesses human transition behavior between automation levels given these factors. The evaluation of these factors involved participants completing a set of tasks in a simulated flight environment and implementing an adaptive automation under varying automation reliability. Additionally, the study entailed the development of a Markovian model, a stochastic model, to quantify the human transition behavior between automation levels in complex systems.
Findings from this research offer the potential to identify key design factors relevant in the design of automated systems, and how these factors could ultimately contribute to human-transition behavior in a hybrid-automated system. Ultimately, the inferences of this study could inform designers on how to effectively determine the appropriate automation level for a system to enhance performance, user engagement, and user satisfaction, with the goal of creating a user-centered hybrid automated system
Interpersonal comparison, trait competitiveness, and eating disorder symptomatology among adults with and without eating disorders
No full textEating disorders are deadly mental illnesses with high personal and societal costs, underscoring the need for greater understanding and more effective interventions. Research suggests that individuals with eating disorders endorse greater competitiveness and maladaptive comparisons compared to their healthy counterparts. This study evaluated differences in competitiveness, eating disorder related comparisons (i.e., food-, body-, and exercise comparisons), and eating disorder symptomatology among individuals with and without eating disorders and between those with restrictive eating disorders and other types of eating disorders. After eliminating probable fraudsters and bots, a total of 783 individuals completed the study. Results suggest that eating disorder comparisons most strongly predicted eating disorder symptoms, and individuals with eating disorders endorsed higher rates of comparison and competitiveness compared to healthy participants with or without an eating disorder history. There were no differences among individuals with restrictive eating disorders compared to those diagnosed with other eating disorders. This suggests that maladaptive interpersonal processes could play a role in the etiology and maintenance of ED symptoms and should be investigated further
Navigating queerness in conservative classrooms: The experiences of queer teachers in Oklahoma public schools
No full textThis study explores the lived experiences of queer teachers in Oklahoma public schools. Grounded in narrative inquiry and informed by queer theory and critical pedagogy, this qualitative study centers the stories of educators whose identities are often marginalized in public education systems. In a state marked by increasingly hostile legislation and conservative cultural norms, queer teachers navigate a constant negotiation of visibility, safety, and professional legitimacy. Data were collected through semi-structured interviews with queer-identified public school teachers across various Oklahoma districts. Participants were invited to share stories about their teaching lives, identity navigation, and interactions with school culture and policy. Using thematic analysis rooted in in vivo and descriptive coding, interview data were examined to identify patterns, tensions, and shared moments of resistance and resilience. Findings reveal the ongoing emotional and professional labor required to survive as a queer teacher in environments that often prioritize compliance and silence over inclusion and care. Central themes include fear of retaliation, lack of policy enforcement, informal networks of support, and the deep internal negotiations that come with balancing authenticity and professional risk. Participants’ stories illuminate how queer teachers resist normative expectations, build community, and create meaning in their practice despite institutional barriers. This study does not treat queerness as a liability or deficit but instead affirms it as a site of insight, critique, and transformative possibility. By listening closely to those who work inside the system while existing outside its dominant norms, this research highlights the urgent need for more inclusive school climates, not only for queer students but for the educators who serve them. This project contributes to the growing body of literature on LGBTQ+ educators and calls on school leaders and policymakers to reimagine educational environments that honor the full humanity of their staff
Genome-wide association studies (GWAS) for germination efficiency, drought resistance, and growth traits in common bermudagrass
No full textCommon bermudagrass [Cynodon dactylon (L.) Pers. var. dactylon] is a vital warm-season perennial grass species with great economic and ecological values for use as turf, forage, and soil conservation and remediation. Seeding offers significant economic advantages over vegetative propagation for establishing bermudagrass. However, the adoption of seeded cultivars is limited by slow germination speed and low germination rates. In addition, adaptive traits such as establishment rate, winter hardiness, and drought resistance are key targets for breeders seeking to improve bermudagrass performance. However, the molecular resources necessary to develop improved and resilient seeded bermudagrass cultivars remain underexplored. Accordingly, the objectives of this study were to quantify genetic variance and to identify genetic variants controlling germination efficiency, establishment rate, winter hardiness, and drought resistance. A diverse panel of 216 genotypes was formed for genome-wide association studies (GWAS). Seed germination traits (germination potential, rate, final percentage) were phenotyped over two runs in a randomized complete block design (RCBD) with three replications. Field evaluation for establishment rate, spring green-up, and drought response traits were conducted in a replicated field trial with RCBD over two seasons (2023 and 2024) in Stillwater, OK. Substantial phenotypic and genetic variation were observed across traits, with reliability estimates for germination traits ranged from low to high (0.23-0.82), the reliability estimate for establishment rate was high (0.64), the estimate for spring green-up was moderate (0.55), and the estimates for drought response traits ranged from low to high (0.12-0.63). The panel was sequenced, and 21,810 high quality single nucleotide polymorphisms (SNPs) were used for association mapping. GWAS identified 38 marker-trait associations (MTAs) for germination traits, 23 MTAs for establishment rate, 13 MTAs for spring green-up and 28 MTAs for drought response traits, accounting for phenotypic variance up to 64.32%. The results of this study add valuable information of genetic mechanisms for germination efficiency, establishment rate, spring green-up and drought resistance, providing specific sequences for marker-assisted breeding to develop new common bermudagrass cultivar with improved germination, establishment, winter hardiness, and drought resistance
Insurance in the aftermath: A qualitative content analysis examining the emergency management cycle and insurance issues across three U.S. circuit courts
No full textFrom the 1980s to today, the United States has experienced an increase from an average of 3.3 to 23 billion-dollar disaster events each year. As natural extreme events continue to challenge communities, the intersection of legal liability and insurance issues becomes increasingly important in disaster management. However, applying legal liability and insurance laws during various phases of the emergency management cycle remains ambiguous. This dissertation aims to shed light on the legal and insurance issues that arise at all stages of disaster management and develop policy recommendations that can address identified gaps or inconsistencies in the application of insurance and liability frameworks within emergency management by asking: (1) What legal liability issues have been addressed in court cases related to the emergency management cycle in the 5th, 8th and 10th U.S. Circuit Courts of Appeals? (2) How have the courts interpreted and applied relevant insurance laws and policies in these cases? By understanding how the court system reviews insurance policies following disasters and identifying significant issues within the law in these areas, regulations can be implemented to address the disparities, allowing greater risk transference or the development of public-private partnerships and risk-sharing programs to close the disaster insurance gap that currently exists in the U.S. To achieve these objectives, a Qualitative Content Analysis (QCA) was conducted reviewing 63 cases, which identified 65 codes, organized into 10 distinct categories, and further grouped into three overarching themes: (1) private insurance issues, (2) government-backed insurance issues, and (3) public policy and human factors. Key issues include standardized policy language, accurate and reliable claims processing, and reforming problematic policy sections to reduce litigation. The Federal Tort Claims Act and government immunity raise questions about the need to balance government accountability with the need for emergency managers to have the flexibility to manage disaster events appropriately. Policymakers must address these challenges while ensuring that insurance and emergency management systems work together to provide timely and effective recovery support
Integrating undergraduate mathematics concepts into secondary mathematics lessons to promote advanced mathematical thinking
No full textResearch has documented that there are many ways to support students’ conceptual learning of mathematics. As Peter Liljedahl described in his book, Building Thinking Classrooms, mathematical learning is achieved by creating a “thinking classroom.” The process by which a thinking classroom is established is based on years of research by Liljedahl and his colleagues. These scholars have identified the characteristics of the optimal environment to promote students’ mathematical learning. One of these characteristics is the availability of high quality instructional and curricular resources. Currently there is a deficit of such resources in secondary mathematics classrooms. The central focus of this thesis is to address this need by presenting a series of mathematical tasks designed to engage secondary students in advanced mathematical thinking. For each task I (1) discuss the principles that informed its design, (2) present the task and its solution, (3) describe my expectations for how the task might support students’ learning, and (4) reflect on my implementation of the task in a classroom setting if applicable
Sensory experience: A qualitative analysis of the behavioral influence of multi-sensory cues in retail
No full textBrick-and-mortar retail stores have experienced growing competition from online retailers in recent years. Multi-sensory retail design has become a topic of interest, as it allows retailers to create unique and memorable experiences that engage the senses, experiences that online competitors cannot make. However, existing research on retail sensory design has focused on individual sensory cues, specifically visual cues, rather than exploring how multiple sensory cues interact together. Therefore, there is a critical need to understand how multi-sensory cues influence consumers' responses and behavior. The purpose of this study is to explore how multi-sensory cues—color, lighting, music, and scent—in retail environments influence consumer emotions, perceptions, and behavior through the lens of the Stimulus-Organism-Response (S-O-R) theory. The study recruited 25 participants from a midwestern university. Participants were immersed in a virtual retail store designed with a white interior, warm lighting, lavender scent, and classical music playing in the background. Data was collected through in-depth qualitative interviews about their experience and thematically analyzed. Findings revealed that a harmonious combination of sensory cues enhanced emotional responses. Positive emotions such as calmness, comfort, curiosity, enjoyment, and happiness were associated with satisfaction, intent to spend more time, and intent to purchase. The sensory cues also influenced positive perceptions of a clean, comfortable, inviting, and relaxing environment. These perceptions also positively influenced satisfaction, time spent, and intent to purchase. The perception of a relaxing environment made participants feel calmer, slowed down their pace, reduced sensory overload, and made people feel more in control of their purchasing decisions. While this study provides valuable insights, these findings are based on a virtual retail environment. Additionally, retail brands communicate their identity through the design of the store. Therefore, these insights should be validated in physical stores and aligned with the brand’s identity before implementation. Overall, this study contributes to the limited body of literature on multi-sensory retail design and provides a foundation for future studies, designers, and retailers aiming to create unique, engaging, and memorable retail environments that emotionally connect with consumers to enhance behavioral responses