Open Research Oklahoma (Oklahoma State Univ.)
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System identification of emergent dynamics in multi-agent systems
No full textMulti-agent systems, whether biological or engineered, exhibit robustness and adaptability through decentralized decision-making and local interaction rules. Understanding the underlying principles governing these systems is critical for both scientific discovery and engineering design.This dissertation investigates system identification in multi-agent systems from multiple perspectives. A heuristic test for emergence recognition is developed, grounded in a mathematical formulation, to characterize collective order from a macroscopic viewpoint. Flight trajectories of insects and birds are analyzed using graph-theoretic methods to estimate agent-to-agent connectivity. To further understand how these interactions depend on factors such as metric distance or topological neighbor order, a generalized interaction function identification framework is formulated. The analysis reveals species-specific behavioral trends such as distance-dependent attraction and velocity alignment, which provide insight into swarm coordination. Beyond biological systems, the framework is extended to analyze impulse responses in engineered systems, particularly spacecraft–debris collisions in low Earth orbit (LEO). By analyzing altitude deviations as impulse responses, a method for detecting debris impacts is proposed. Collectively, these findings advance the understanding of emergent dynamics in complex multi-agent systems and establish a unified methodology for identifying interaction mechanisms across different domains
Teacher understandings of and interactions with the English language proficiency assessment
No full textThis qualitative critical case study explores how K-12 educators in a Southern, urban school district understand and engage with English language proficiency assessment (ELPA) policies and practices. Using critical theory and incorporating frameworks of linguistic justice and test usefulness, the study explores how standardized language assessments operate as tools of norm enforcement, potentially marginalizing students whose linguistic repertoires or use of English fall outside standard norms. Data were collected through semi-structured interviews with seven educators working with multilingual learners, a focus group, and state and testing policy document analysis. Data were analyzed thematically, iteratively using inductive and deductive coding. The analysis was guided by theoretical lenses including critical inquiry, translanguaging, linguistic justice, and test usefulness.
Four central themes emerged: (1) tension between educator and policy definitions of proficiency; (2) reinforcement of unrealistic expectations through proficiency testing and placement; (3) educator critiques of and resistance to standardized assessment; and (4) enactment and justification of programming practices that support multilingual students. While participants challenged the adequacy of assessment tools, they simultaneously valued and justified the EL programs within their schools. Differing definitions of proficiency and significant challenges to the tenets of test usefulness provide evidence that standardized language assessments in schools may be actors of linguistic injustice. This research contributes to the growing body of research critiquing high-stakes language assessments and calls for a more equitable, contextually responsive approach to language proficiency assessment through modifications to testing, proficiency definitions, and the conceptualization of ELD programming
How lesbians perceive and navigate discrimination from their child’s school
No full textThis study aimed to understand how lesbian parents experience and navigate perceived discrimination from their child’s school in states that have laws against LGBTQ curriculum. Using an interpretivist case study approach and semi-structured qualitative interviews, I explored the experience of lesbian mothers and what they perceived as discrimination using Bronfenbrenner’s Ecological Systems Theory and Queer Theory. The findings revealed that lesbian mothers share five themes in which they report perceived discrimination, and use a direct, educational approach to combat the perceived discrimination. The five themes that emerged from analyzing the data are lesbian mothers wanting to be acknowledged and supported in schools, wanting school children to be exposed to diverse family structures (e.g., same-sex parent households), viewing political affiliations of school workers as a sign of approval or disapproval of same-sex relationships, wanting documents at schools to be representative of different family structures, and believing that educating people is the way to negate confusion of family structure
Stress in context: Discrimination, early adversity, and the rhythms of cortisol
No full textStress physiology develops through ongoing interaction with the environments people move through, leaving measurable signatures of both early adversity and current social experiences. Emerging adulthood is a period when these influences often converge, particularly for marginalized young adults who navigate developmental transitions alongside persistent exposure to discrimination. Guided by evolutionary-developmental models of stress calibration, the present study examined how early-life adversity, perceived discrimination, and emotional support relate to multi-day patterns of diurnal cortisol slope, a multi-day indicator of the stress system’s characteristic daily rhythm, reflecting accumulated environmental inputs. Seventy-three emerging adults of color (ages 18-25) completed laboratory surveys and a week-long, at-home protocol involving waking and bedtime salivary cortisol collection across three nonconsecutive days. Early adversity was assessed through Adverse Childhood Experiences (ACEs), past-year family stress, economic strain, and interpersonal trauma. Perceived discrimination was measured with a validated trait-level index capturing experiences of unfair treatment across social contexts. Emotional support was assessed across key relationships, including caregivers and best friends. Across analyses, early adversity, perceived discrimination, and emotional support each showed small and inconsistent associations with diurnal cortisol slope. Although none of the predictors reached statistical significance, the directional patterns were generally consistent with theoretical expectations: greater adversity and higher perceived discrimination tended to correspond with slightly flatter slopes, whereas higher emotional support was associated with somewhat steeper slopes. These trends were modest and should be interpreted cautiously given the study’s limited power to detect small effects typical of psychobiological research. Despite these limitations, the study demonstrates the value of a within-group approach and multi-day cortisol assessment for understanding how developmental history and social context shape daily stress physiology among emerging adults of color. The findings underscore that physiological patterns are not fixed markers of dysfunction but may reflect context-sensitive adaptations to environmental demands, offering a foundation for future work using larger samples and more fully powered designs
Grazing interactions: Cattle, goats, and fire in a changing landscape
No full textWoody plant encroachment threatens rangeland productivity globally, yet traditional management approaches using fire, herbicides, or mechanical removal provide only temporary control. My work evaluates a management framework that combines pyric herbivory (interaction between fire and grazing) with mixed-species grazing to address woody and invasive plant encroachment in tallgrass prairie rangelands. I reviewed ecological processes impacting woody encroachment and examine pyric herbivory coupled with mixed-species grazing as an alternative management strategy. This review synthesizes evidence for how cattle and goats create complementary disturbance through different dietary preferences, potentially enhancing woody plant control beyond single-species systems. Next, I examined patch selection behavior of cattle and goats in a pyric herbivory system across 6 pastures. Using GPS collar data, I found both livestock species selected recently burned patches, with selection decreasing as time since fire increased. While cattle selection was strongly influenced by burn season, goat selection showed greater variability, suggesting complementary grazing patterns that could enhance landscape-scale management. We then tested treatment effectiveness using paired exclosures across the same pastures to compare fire-only, cattle-only pyric herbivory, and cattle with goats pyric herbivory on three target plant species: Rubus spp., Lespedeza cuneata, and Rhus spp. Fire-only treatments allowed target species height and vertical obstruction to increase 41-183% over three years. Cattle-only pyric herbivory partially suppressed regrowth, while adding goats reversed growth trends, reducing height up to 28% and vertical obstruction up to 40%. Finally, I evaluated community-level vegetation responses, finding that adding goats increased grass cover by 14% but did not reduce total woody cover. Instead, goat browsing restructured the woody community, which decreased palatable species while inadvertently favoring browse-resistant species. These findings demonstrate that integrating goats with cattle in pyric herbivory systems enhances forage production and provides targeted control of species woody species, though not broad-scale woody plant reduction. This research provides evidence-based guidance for managers implementing mixed-species grazing strategies in rangelands
Optimizing plant biodiversity monitoring through environmental DNA
No full textEnvironmental DNA (eDNA) metabarcoding is an emerging tool for plant biodiversity monitoring, offering a non-invasive and scalable alternative to traditional field surveys. By amplifying and sequencing trace genetic material from environmental samples, eDNA enables detection of multiple taxa with minimal disturbance. Despite its widespread application in animal and microbial monitoring, plant-focused eDNA studies remain underdeveloped, comprising only a small fraction of total eDNA research.
Given the foundational role of plants in ecosystem function, improving methods for plant biodiversity monitoring is imperative. In particular, freshwater plant communities are undergoing significant biodiversity loss, and effective monitoring is critical for detecting changes and informing conservation strategies. Yet, standardized sampling designs are lacking, which risks introducing bias or inconsistency into biodiversity assessments. To fully realize the potential of eDNA for plant ecology, optimized and reliable field practices are essential. This study evaluates how vertical sampling position (surface vs. benthic) affects eDNA-based plant diversity estimates in freshwater lakes.
We analyzed 950 water samples collected from 22 lakes across Michigan, using surface (Smith-Root backpack samplers) and benthic (Van Dorn samplers) collection methods. DNA was extracted and amplified using primers targeting the plastid gene region rbcL, a widely used barcode for vascular plants. Species richness and Shannon diversity were calculated for aquatic, wetland, and terrestrial plant groups, and compared using Wilcoxon rank-sum tests.
Our results revealed no consistent differences in alpha diversity between surface and benthic samples across most lakes and plant groups. These findings suggest that single-depth sampling may often suffice for estimating local plant diversity, offering opportunities to streamline field protocols and reduce sampling effort.
By identifying conditions under which simplified sampling strategies yield comparable results, this study contributes to the scalability and cost-efficiency of plant eDNA monitoring programs. Future work should examine how depth influences beta diversity and community composition, and consider other spatial factors, such as distance from shore, that may differentially affect the detectability of aquatic versus terrestrial taxa. As environmental pressures intensify, flexible and robust tools like eDNAPlant Biology, Ecology and Evolutio
Digital dilemmas: Influence of peer pressure and attitude towards digital privacy in social media users
No full textIntroduction: Technology has become integral to day-to-day life in the digital era, particularly social media platforms such as Facebook, X, YouTube, and Instagram. They are now the most common way to connect billions of people worldwide. Social media has transformed how people communicate, share information, build communities, and foster global connections at our fingertips. (Bengtsson & Johansson, 2022). However, the widespread use of social media has also raised concerns regarding privacy, misinformation and fake news, online addiction, bullying and harassment, digital peer pressure, and mental health impacts (Dhiman, 2023). One of the rising concerns is the dilemma between digital peer pressure and digital privacy, where individuals struggle to balance social acceptance with protecting personal information (McClain, 2023). To address this issue, the current study examines the influence of digital peer pressure on the understanding and practices of digital privacy among social media users. It provides an understanding of the behaviors and attitudes of social media users.Method: A systematic survey questionnaire was developed to examine the understanding of digital peer pressure and digital privacy among social media users. The survey was created using Google Forms, an online data collection tool. The survey link was shared across various online and social media communities to reach a diverse participant pool. Data was collected from Individuals willing to participate in the survey voluntarily and directed to the survey link. The participants in the study were mostly between 18 and 44 years old, with the majority of them having an education level of at least a master's degree. The collected data was then analyzed using tools like MS Excel and Python.Results: The study findings reveal the influence of digital peer pressure on users' understanding of digital privacy practices. All users in the study prioritized social acceptance over privacy, with each having at least one social media platform. Many participants indicated that they agreed to the privacy policy without reading it and often shared personal information despite privacy concerns. Additionally, the study observed that many participants were aware of digital privacy, contributing to a somewhat improved social environment.Conclusion: The study highlights the need for increased awareness and education on digital privacy to help users manage the challenges of digital peer pressure. Addressing this issue is needed for creating a safe digital environment for all users
Mapping early-life stress-induced behavioral adaptations in adolescent rats
No full textIntroduction/ Objectives: Adverse childhood experiences (ACEs) are deviations from standard conditions requiring significant psychological and neurobehavioral adaptations and can be modeled in rats through limited bedding and nesting (LBN) for postpartum dams. LBN disrupts maternal care, leading to behavioral adaptations in adult offspring. Additionally, adolescence is a critical period for social development; however, few studies exist examining this time point. In this study, we investigated the impact of LBN on social preference in adolescent rat males and females.Methods: Female dams and their pups were exposed to either LBN conditions or normal bedding and nesting (naive) from postnatal day (PND) 2 to PND9. LBN conditions were normalized at PND10. Pups remained with their mothers until PND21, after which they were weaned and housed with same-sex littermates. At PND45, when rats reach adolescent age, social preference was assessed by measuring the amount of time an experimenter rat interacted with either a bystander rat or an inanimate object.Results: Our findings reveal that adolescent females exposed to LBN exhibited a significant preference for inanimate objects oversocial interaction with an unfamiliar bystander. In contrast, no significant differences were observed in social interactions with a familiar bystander, regardless of sex or stress condition.Conclusion: These results highlight sex-specific effects of early-life stress on social behavior and suggest adolescent females show preferential susceptibility to a disruption in social preference
Eyewitness testimony and gender in violent crimes
No full textThe present study experimentally investigates the effect of gender on the accuracy of eyewitness testimony. I ask whether feminine or masculine persons give a more accurate testimony after witnessing crimes with varying levels of violence and with female or male presenting victims. Participants are randomly assigned to a vignette that describes a crime that contains either no violence, threats present, or physical violence. The victim will either be male or female-presenting. Participants are then asked to recall details about the victim, perpetrator, and crime setting. It is expected that women will perform better in the violent condition than the threat or no violence condition. It is also expected that women will provide more accurate testimony overall, and women will provide more accurate details of victims who are also women.Sociolog
Gender-based investigation of 17 β hydroxysteroid dehydrogenase 13 in HCV-induced cirrhosis and hepatocellular carcinoma
No full textIntroduction/Objectives: Hepatitis C virus (HCV) infection- related inflammation, liver fibrosis and cirrhosis often lead to development of hepatocellular carcinoma (HCC). In the United States, 4.6 million people are infected with HCV. Studies show that chronic HCV infections are more prevalent in males and progress more rapidly to cirrhosis and cancer development as compared to females. In contrast, premenopausal females and women on hormone replacement therapy have been associated with lesssevere disease through all stages of HCV infection. Estrogen Receptor signaling is known to regulate inflammation and immunity. We have previously identified sex-based differences in the expression of estrogen receptors (ERs) in normal livers and dysregulated mRNA and protein expression of ER subtypes in both HCV-related cirrhosis and HCC suggesting a possible role in its pathogenesis. Given the United States opioid epidemic and high rates of intravenous drug use, Hepatitis C is an emerging disease among women of child-bearing age (and subsequently, pregnant women). Therefore, HCV-positive pregnant women with high levels estrogen may also be affected by modified behavior of HSDs. As such, our studies can apply to a broad group of people and demand further investigation. Our current study investigates the hydroxysteroid dehydrogenase enzyme family (HSD). HSDs contribute largely to the synthesis and degradation of steroid hormones such as testosterone and estrogen sex-hormones, as well as cholesterol and fatty acid metabolism. They have also been shown to confer involvement in carcinogenesis of extra-hepatic cancers affecting structures such as prostate, breast, and pancreas. Estrogen Receptor signaling is known to regulate inflammation and immunity. Chronic inflammation due to HCV infection in the liver may alter HSD enzyme regulation and alter hormone metabolism. Further, this pro-inflammatory state may contribute to the development of HCC which may be modulated by altered HSDs.Methods/Results: Our current study utilized proteomic analysis to determine sex-based differences in HSD protein expression in male and female HCV cirrhosis and Hepatocellular Carcinoma (HCC), with specific interest in 17 β Hydroxysteroid Dehydrogenase 13 (HSD17B13). We studied a total 65 liver tissues that included both sexes from HCV-related cirrhosis, HCC, and normal controls. Using proteomics analysis, clinical correlates, western blotting, and immunohistochemistry techniques, our studies showed that HSD17B13 is present in both males and females and that females with HCC and females with HCVinduced cirrhosis have statistically significantly higher levels of the enzyme as compared to healthy control females and male with HCV-induced cirrhosis, respectively. Clinical marker aspartate aminotransferase (AST) shows a significant and inverse relationship to HSD17B13 expression among the HCC cohort as well. HSD17B13 protein may serve as a sex-based biomarker in liver cirrhosis and cancer development.Conclusion: To the best of our knowledge this is the first report showing sex-based differences in HSD proteins in premalignant HCV-related cirrhosis. Further investigations with a larger group of patients may impress upon us new sex-based tailored clinical therapies in halting cirrhosis and HCC progression in males