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Item type:Item, Access status: Open Access , Characterization of freshwater macroplastic-associated bacterial communities using 16S rDNA sequencing(2026) Sharma, ShreyaPlastic pollution has become a major concern across all ecosystems, especially in freshwater environments. Freshwater bodies such as rivers, lakes, and streams serve as hotspots for accumulation of plastic waste, providing an interface for colonization and further succession of a self-sustaining microbial consortium known as the "plastisphere". In this study, plastisphere communities were sampled from individual and rafted, purposefully deployed and pre-existing polyethylene (PET), polypropylene (PP), polystyrene (PS) substrates during June, July and August 2025 at Arcadia Lake, Edmond, OK, USA. The microbial communities collected were further characterized using 16S rDNA metabarcoding. Wood substrates were also sampled to represent naturally occurring microbial communities. Our research supports primary influences of substrate type and sampling time on the progression of the plastisphere. Alpha diversity analysis revealed that PET and PP showed similar levels of microbial diversity while PS was similar to wood. Family Leptolyngbyaceae was the most abundant family on all substrates across the sampling duration. Substrate preference was observed in families Rhodobacteraceae and Nostocaceae for PET and PP when compared to PS and wood. Additionally, Cyanobiaceae and Deinococcaceae were abundant on PS compared to other plastic substrates. Wood was enriched with Beijerinckiaceae for all three months. Across the sampling period, the abundance of Leptolyngbyaceae on PET and PP was highest in June and lowest in August while Nostocaceae was recovered to be abundant in July and August. Rhodobacteraceae was abundant in June on all the samples compared to June and July. Beta diversity analysis further supported our alpha diversity findings. Weighted UniFrac ANOVA analysis revealed significant results for individual factors such as substrate, collection date and combination factors substrate+collection date and substrate+single/rafts. Additionally, ANOVA analysis for combination factor substrate+artificial/naturals was recovered to be significant for all beta diversity measures including Bray-Curtis, Jaccard, UniFrac and wUniFrac. Finally, PERMANOVA analysis demonstrated significant results for substrate and collection date (time) establishing the importance of time in shaping plastisphere microbial communities along with substrate. Although numerous studies have shown the influence of a variety of factors on plastisphere succession, there is still a need to characterize the "global" plastisphere community while simultaneously determining the driving factors involved in shaping microbial succession among these communities. Abbreviations: PET-polyethylene terephthalate; PP-polypropylene; PS-polystyrene; ANOVA-analysis of variance; PERMANOVA- permutational multivariate analysis of variance.Item type:Item, Access status: Open Access , All posers must die: the paradoxical relationship between the self and community in 19th century American literature and hardcore music(2026) Pierce, WesleyThe American Romantic period is a literary space that holds a high level of academic significance. Hardcore music genres Punk, Thrash Metal, and Groove Metal all represent aspects of the cultural time period that they occupy. The tendency to view these artistic mediums as separate presents the concern: how are they the same? Hardcore music is a reiteration of Romantic period sentiment due to its use of social satire and shared celebratory language; Hardcore music highlights that the tension between the Dark Romantics and Transcendentalists is actually the solution to the questions that they pose. F.O. Matthiessen, David Reynolds, and Robert Pattinson discuss how the significance of this literary period is rooted in the synthesis of political writings, reform cultures, frontier humor, and philosophical texts; this synthesis creates the binary opposition of the Dark Romantics and the Transcendentalists. This synthesis of ideas continues as the themes of this period blend with various musical styles, like Folk and Blues, to create the foundations of Hardcore music. The understanding that these ideas are carried from proto-Romantic creatives to proto-Hardcore musicians furthers the significance of Hawthorne, Whitman, and Melville. The methods employed in this thesis is comparative analysis of these authors and musicians Woody Guthrie, Robert Johnson, the Circle Jerks, Black Flag, Metallica, Pantera, and Corrosion of Conformity. These artists confirm that these themes are so culturally significant that they show up in places that are often unexpected. These findings illustrate not only the impact of 19th century authors, but allows for further eras of study. Further areas for research include Romantic period connections to Riot Grrrl Punk, Indigenous Metal, and Gothic literatures ties to the Emo music scene, and how Hip-Hop functions similarly.Item type:Item, Access status: Open Access , Developing a new dataset and method for the interpretation of firearms evidence(2026) Klaus, NathanFirearms evidence has long been utilized in investigations and in the courtroom. Emerging technologies have made the examination of firearms evidence, namely expended cartridge cases, an easier process. Recent technologies enable the use of computer algorithms to provide quantitative comparisons. However, many of the cartridge case datasets used to develop these algorithms are limited in number and scope, in particular insufficient accounting for variability expected to occur within markings produced by a single firearm. The goal of this research was to develop a new dataset consisting of 31 HiPoint C9 firearms with 17 cartridge cases fired from each. These cartridges were scanned using the Cadre Forensic TopMatch 3D instrument and assigned similarity scores by the TopMatch 3D algorithm. These similarity scores were then analyzed using both kernel density estimation and generalized linear mixed models. Kernel density estimation had difficulties due to the low distribution of scores among firearms tested. GLMM, however, offered a means by which a percentage probability of same- or different-source conclusion could be assigned to similarity scores of a model of firearm. This method has the potential to be expanded to other firearms and offer some quantification to the field of forensic firearms analysis.Item type:Item, Access status: Open Access , Unpredictable indulgence: how childhood unpredictability and deprivation influence adult materialism(2026) Hinman, Eileen V.Evolutionary mismatch perspectives suggest that some behaviors that benefitted humans in evolutionary contexts may be maladaptive in modern society. One example is spending behavior, which previous research has found to vary by life history strategy. Life history theory is an evolutionary theory that proposes that the levels of harshness and unpredictability in childhood environments shape behavior throughout life. Recently, researchers have incorporated the threat-deprivation model of childhood adversity to better understand the individual and interacting long-term effects of adverse experiences. While this integration of evolutionary and developmental perspectives opens a wealth of potential research paths to better understand the intricacies of how people function in modern society, inconsistencies in measurement and methodology have resulted in diverse findings. This project seeks to contribute to this growing body of work by expanding on previous findings concerning spending behavior and life history strategy, as well as comparing different measurements of unpredictability and deprivation. In line with the results of previous studies, I propose that individuals with high levels of childhood deprivation and unpredictability will have a greater desire to conspicuously consume, while individuals who experienced low levels of each will result in a greater desire to save money. Analysis found that in the economic threat condition, low levels of deprivation predicted higher levels of saving when unpredictability was low, but not when it was high. Future research can continue to delve into the nuances of dimensional measures as well as explore the role of threat in adult behavior.Item type:Item, Access status: Open Access , Your poker face under pressure: autonomic nervous system arousal as a moderator of the relationship between expressive suppression and facial affect sensitivity(2026) Anderson, KalaExpressive suppression is an emotion regulation strategy that involves inhibiting the outward expression of emotion and can influence both the experience and perception of emotions (Gross, 1998a). Research suggests that expressive suppression impairs facial affect sensitivity, or the ability to accurately identify emotions in others' facial expressions (Schneider, Hempel, & Lynch, 2013). The present study investigates the impact of expressive suppression on university students' facial affect recognition and whether autonomic nervous system (ANS) arousal moderates this relationship. Participants completed a facial effect recognition task involving gradually morphed expressions ranging from neutral to full emotional intensity. During the task, participants were instructed to either suppress their expressions or maintain a natural, relaxed expression. ANS arousal was induced via cold pressor intervention, and heart rate was measured using electrocardiography (ECG). Response time, accuracy, and heart rate change over time were assessed using multiple analyses of variance. Although results were not significant, several outcomes trend in the hypothesized direction, suggesting that a more robust sample is necessary to fully investigate the role of ANS arousal on the relationship between expressive suppression and facial affect sensitivity.