Digital Commons Network^™

Online Decision Mamba, Trenton W. Ruf

Dissertations and Theses

Online in-context reinforcement learning enhances offline-trained policies through online fine-tuning. We introduce Online Decision Mamba (ODM), an architecture that replaces the attention mechanism in Online Decision Transformers (ODT) with the Mamba module to improve long-context sequence modeling and overall RL performance. We performed in-depth evaluations on MuJoCo (OpenAI Gym) and Atari benchmarks, comparing ODM against state-of-the-art offline and online baselines—including Decision Mamba (DM) and ODT. Our results show that ODM achieves competitive or superior performance, with particularly robust gains when initial datasets lack expert demonstrations. In the Qbert Atari environment, ODM shows context-length sensitivity similar to offline DM; however, we …

Spike Timing Depended Plasticity Produces Unsupervised Learning Of Synergistic Muscle Feedback In A Synthetical Neural Network, Mark Allen Pupkiewicz

Dissertations and Theses

This study investigates how type Ia feedback from muscle spindles can be organized into groups representing agonistic muscle pairs through Spike Timing Dependent Plasticity (STDP). A single degree of freedom joint is actuated with four biologically modeled muscles forming two agonistic pairs. In order to emulate the sensory dynamics of biological muscle spindles, sensors in the model record the active length and velocity states of each muscle, the two primary factors eliciting type Ia afferent responses. In biological networks, synapses from Ia sensory neurons frequently activate interneurons representing agonistic muscle sources. This research investigates whether this organization can emerge in …

Medicaid Funding And Health-Related Social Needs: A Policy Analysis, Passion Ilea

Dissertations and Theses

The U.S. has disproportionately high health care spending compared to other high-income nations and comparatively poor health outcomes. The Centers for Medicare and Medicaid Services (CMS) have recently increased emphasis on addressing Medicaid member social needs. CMS believes addressing health-related social needs (HRSN) may reduce costs and improve health outcomes for Medicaid members. CMS has begun to test theories regarding the impact of member HRSN on health care by designing federal mechanisms to address HRSN, such as in lieu of services and settings-funded services, and by encouraging state Medicaid programs to develop their own approaches, such as Flexible Services. Information …

In-Between Spaces: First-Generation College Immigrant Experiences, Silvina Alamo Sousa-Ransford

Dissertations and Theses

It is human nature to seek a sense of belonging, acceptance, and community. College students also share this desire for connection in higher education, but some face more barriers and challenges. This study examined the experiences of first-generation college students who are also immigrants. The goal was to understand how to best support students in college, including through academic advising, at a four-year research university in the Pacific Northwest. To gain insight into the students' experiences, I interviewed participants using narrative qualitative methods guided by the framework of sense of belonging and analyzed the data utilizing Bronfenbrenner's Ecological Model. The …

Flow Control Tactics For Photovoltaic Modules: Coherent Structure And Heat Shedding Amplification, Sarah Elizabeth Smith

Dissertations and Theses

Solar photovoltaic systems have become the fastest growing renewable technology in the last several years. However, large-scale systems are at the mercy of their external environments, where extreme heating and wind-flung debris impact their efficiency and useable life. The work in this dissertation presents studies aimed to both understand and mitigate for these effects by identifying the underlying physics which govern them. Exploring flow control as a tactic to combat environmental heating, collective work discusses the role of turbulent fluid dynamics within large-scale systems as pertains to convective heat transfer, turbulent structure formation, and particle-laden environments. Wind tunnel experiments on …

Digging Deeper With Deep Ram Networks, Andrew J. Wagner

Dissertations and Theses

While Deep Neural Networks (DNNs) have driven major breakthroughs in artificial intelligence, their internal complexity often makes their behavior hard to explain, resulting in the well-known “black box” dilemma. This thesis addresses the challenge of interpretability in DNNs and deep reinforcement learning (DRL) through two main contributions.

In Part I, we revisit and extend the use of Deep RAM Networks (DRNs) within the Arcade Learning Environment (ALE), showing that, with modern architectures and careful hyperparameter tuning, RAM-based agents can achieve performance competitive with established pixel-based baselines on Atari 2600 games, while offering additional advantages for research and analysis. We also …

Characterizing Meteorological Patterns For Oregon's Winter Elevated Pm2.5 Concentrations From 2000-2023, Arielle Golda Sherbak

Dissertations and Theses

Valleys and basins are uniquely susceptible to the buildup of air pollution during the wintertime due to cool, dense air pooling under favorable meteorological conditions, a common occurrence in the Intermountain West. In Oregon, wintertime anthropogenic air pollution is primarily from woodburning stoves and heaters and although efforts have been made to reduce wintertime pollution, stagnation events continue to result in decreased air quality. This analysis aims to understand the relationship between air pollution in six Oregon counties and the associated meteorology in the cool season (November-March) using a 2000-2023 climatology.

This is completed through a composite analysis using key …

An Evaluation Of Therapeutic Harm Reduction And Psilocybin-Assisted Therapy Within Oregon's Measure 109, Bodhi Norton

Dissertations and Theses

Despite psilocybin still being a Schedule I substance in the Federal Controlled Substance Act (OHA, 2022), Oregon voters passed Measure 109 in 2020, now codified into law as ORS457A, which allowed for the opening of psilocybin clinics for eligible clients. The passing of Measure 109 allowed for an adult-use model to be created, which is different from a therapeutic-use model. Advocates and Measure 109 framers employed the terms "harm reduction" and "mental health support" in order to secure the passing of Measure 109, but there is no specific definition of therapeutic harm reduction within M109 and ORS475A. To receive psilocybin …

Exploring Impacts Of Diversity Ideologies On Allyship (Intergroup Responsiveness), Fiona Nguyen

Dissertations and Theses

Colorblindness and multiculturalism are widely studied diversity ideologies that reflect prominent attitudes about how diversity should be understood and managed, as they can help predict individual behavior. Colorblindness proposes that distinct group identities should be ignored, and can be used to exclude minoritized groups and downplay racial minorities' experiences, whereas multiculturalism embraces and values group differences, can foster inclusive environments for minority groups, and leads to positive intergroup outcomes such as reduced prejudice. Despite much research dedicated to exploring the intergroup outcomes of diversity ideologies, few studies have examined their impacts on specific interpersonal interactions, particularly allyship. Research has defined …

Sex Worker Stigma, Morality And Ambivalent Sexism, Emily Kate Kinzel

Dissertations and Theses

Sex worker stigma has received limited attention in psychological research. Although stigma is often theorized to relate to moral concerns, the relationship between stigma and moral concerns has not been empirically established. This study aims to address these gaps by developing a measurement tool for attitudes towards sex workers--specifically an implicit association test (IAT)--and explore the relationships between sex worker stigma, moral concerns, and ambivalent sexism. Mock policy questions on the criminalization and punishment of sex workers were also included to approximate behavioral intentions of participants. A cross-sectional correlational study of 168 community members found evidence that both moral concerns …

What Kinds Of Experiences And Activities Contribute To College Students' Sense Of Purpose? A Mixed-Methods Study, Katlyn Rochelle Viers

Dissertations and Theses

For many young people, attending college is a core marker of the transition to emerging adulthood. Some students thrive in college while others become lost, confused, or seem to be just marking their time. Some researchers have hypothesized that one thing that can help students take advantage of their college experience is if they are firmly anchored in their own life goals and sense of purpose. The primary goal of this study is to contribute to knowledge about the role of a sense of purpose in college students' development, including not only its potential benefits to their academic functioning and …

The Effect Of Mesoscale Frontal Waves On Landfalling Atmospheric Rivers And Their Associated Precipitation Over The Green River Watershed, Washington, Joseph Michael Riedl

Dissertations and Theses

In this study, the effect of mesoscale frontal waves (MFWs) on extreme precipitation (EP) in the Upper Green River Watershed (UGRW), Washington is investigated. 205 EP days (>95th percentile) are identified in the UGRW between the years 1980 and 2021. To characterize the range of large-scale meteorological conditions associated with EP days, the self-organizing map (SOM) approach is used to cluster daily integrated water vapor transport (IVT) on EP days. To further diagnose the meteorological drivers, composites of several other diagnostic fields are constructed for each SOM node and the preceding days. Together, these results illustrate common orientations of …

Orphan Basalts: Understanding The Origins Of Unassigned Eastern Oregon Basalts, Angela Rae Stetson

Dissertations and Theses

For more than a century, scientists have studied the geologic stratigraphy of eastern Oregon, which chronicles a rich history of volcanic activity spanning millions of years. Recent and ongoing geologic mapping of the northeastern Harney Basin -- along a corridor east of Highway 395 between the towns of Burns and John Day -- provides a more detailed understanding of an area originally mapped only in reconnaissance during the 1960s. At that time, geologic units were poorly delineated, often with entire quadrangles mapped as a single unit. For example, over 90% of the Calamity Butte quadrangle was previously mapped as 'Tba' …

Industries, Self-Rated Health, And Status Characteristics: An Exploration Of Health In Industries At The Intersection Of Race/Ethnicity, Gender, And Disability, Emmanuel Legarreta

Dissertations and Theses

While industries, occupations, and health outcomes have been widely studied, research has neglected self-rated health (SRH) and the intersectionality of different status characteristics in various industries. Using an IPUMS version of the Current Population Survey, this study explores the possible relationships between industries and SRH. More specifically, it seeks to find if workers' disability status, racial minority status, or gender moderates (i.e., differentiates) the relationship between their industry and SRH. Findings show that certain industries are significant predictors of SRH, and that women with disabilities working in Mining and Construction, and Business and Repair Service have significantly worse SRH than …

The Living Dead On Mount Athos: Monastic Politics Of Escape, Patrick Reilly

Dissertations and Theses

The Monastic Republic of Mount Athos is a unique and confounding political entity - both Greek and multi-national, democratic and theocratic, autonomous and subject to the European Union - with more than a millennia of history and institutional memory. While Athos has been amply appreciated for its religious, historical and cultural significance, the political institutions which govern this community have been neglected in the modern era and merit greater attention. Similarly, while much of the recent English-language literature on the topic focuses on the near-death and miraculous resurrection of Mount Athos in the 20th century, this work also tends to …

Exploring Underrepresented Stem Undergraduates' Stem Identity Development: The Role Of Social Partners, Sandy Cerda-Lezama

Dissertations and Theses

This dissertation employs a three-study qualitative design to investigate the role of mentorship and social interaction in the identity development of racial minority undergraduate students in STEM disciplines. Grounded in Communities of Practice theory, this research amplifies student narratives to elucidate the relational and contextual factors that inform science identity, belonging, competence, and persistence in higher education. Study One draws upon interview data from fifteen participants in the BUILD program to analyze the role of recognition, particularly from expert scientists--in students' science identity development. This study aims to understand how racial and ethnic identity intersections influence the processes and impact …

Synoptic-Scale Meteorological Patterns Associated With Extreme Precipitation Over The Contiguous United States And Concomitant Seasonal And Regional Variability, Amy M. Johnson

Dissertations and Theses

Seasonal and spatial variations of synoptic-scale weather patterns concurrent to extreme precipitation days, defined as days above the seasonal 95th percentile of the daily precipitation distribution, are characterized over a 44-year period (1980-2023) for the Contiguous United States (CONUS). Using atmospheric reanalysis data and a grid-cell centered approach, we construct seasonal anomaly composite patterns for sea level-pressure (SLP), integrated water vapor transport, 500 hPa geopotential height (Z500), and 300 hPa wind speed. Atmospheric variables known to be important for extreme precipitation. By interpolating composites for each grid cell onto the same polar coordinate grid relative to the grid cell we …

Arbuscular Mycorrhizal Fungi As Key Drivers Of Plant Resilience: Mechanisms Of Stress Adaptation In Saline Environments, Rayna Elizabeth Koberstein

Dissertations and Theses

Arbuscular mycorrhizal fungi (AMF) play a critical role in mediating plant responses to environmental stress, yet their ecological significance in saline wetland restoration remains underexplored. This greenhouse experiment investigated the effects of salinity, root-zone barrier type (solid, mesh, none), and neighboring species identity on AMF colonization and physiological responses in three native estuarine plants: Carex densa, Juncus patens, and Scirpus microcarpus. Results demonstrated species-specific physiological responses to salinity, with Juncus patens showing greater resilience in maintaining photosynthetic efficiency (Fv/Fm) and percent cover at higher salinity levels, while Scirpus microcarpus exhibited a significant decline. Mesh barriers, which permitted …

From Model To Behavior: Methodological Challenges In Using Fuzzy Cognitive Maps To Represent Mental Models, Catherine Elizabeth Moore

Dissertations and Theses

This dissertation examines the use of Fuzzy cognitive maps (FCMs) as representations of mental models and how these representations connect to individual behavior. Fuzzy cognitive maps (FCMs) are semi-quantitative models that encode cause-and-effect structures as directed graphs. They are frequently used to represent individuals' knowledge structures/mental models and should in theory correlate to actions and decisions of individuals; however, this correlation has yet to be explored in a systematic manner. This dissertation represents the first step in experimental research on the connection between FCMs and individual behavior. It examines two theories of how humans use mental models, one based on …

Mechanistic Rationale For Toxic Aerosol Formation From Vaping And Dabbing With A Focus On Ketene Formation From Semi-Synthetic Cannabinoids, Kaelas Ryan Munger

Dissertations and Theses

Cannabis vaping is a relatively new route of administration that is increasingly common among youth and young adults. Cannabis vaping has been associated with cases of acute lung injury, especially among youth, and most often involves the heating and aerosolization of high-potency products having cannabinoid concentrations of ~ 50 % - 98 % w/w. Proponents argue that vaping is safer than smoking due to the characteristically lower temperatures and fewer plant materials. However, the extreme cannabinoid concentrations, along with non-natural formulations having undisclosed additives, require studies of the health effects of these products. Despite the popularity of cannabis concentrate vaping, …

Characterizing Secondary Flow Structures Over Scaled Solar Arrays And Investigating Impact Of System Yaw Angle, Katie Nicole Taylor

Dissertations and Theses

This study investigates Prandtl's secondary flows of the second kind within the turbulent boundary layer over a newly defined type of surface roughness, e-type, which is characterized by roughness elements that are elevated from the wall. This e- type roughness is modeled after photovoltaic (PV) solar panels and its study driven by establishing a more robust understanding into how flow moves through solar arrays as the demand for renewable energy continues to grow.

Wind tunnel experiments using particle image velocimetry (PIV) were conducted over a scaled array of panels and explored how shifting the yaw angle of the …

Developing Workflows For Passive Acoustic Detection Of Bedload Transport, Quinn Morgan

Dissertations and Theses

Bedload transport is defined as the amount of sediment, including gravel and rocks, traveling down stream. Monitoring bedload transport is important for river safety, hydrological studies and conservation efforts. Existing methods of directly measuring bedload transport (or bedload flux) involve lowering a collection device into a river and measuring the sediment collected; which can be expensive and time consuming. Hydroacoustic sensors, such as hydrophones, have had success tracking bedload flux remotely. This works by measuring the relatively high frequency of sediment impacts to map onto total bedload transported. No perfected method for detection of sediment generated noise (SGN) currently exists. …

Barriers Beyond Bars: Examining Experiences Of Students With Criminal Records, Anakin Rivera Ramirez

Dissertations and Theses

As educational opportunities, particularly prison education programs, continue to expand for incarcerated individuals, this study, which included two participants, one formerly incarcerated and one who pleaded guilty to avoid incarceration, suggests that those who plead guilty to avoid prison may enter college without the structured reintegration resources available to their incarcerated peers. While substantial research has explored the school-to-prison pipeline phenomenon in K-12 settings, fewer studies have examined its impact on students with criminal records navigating higher education. Grounded in Critical Race Theory (CRT) in education, this study seeks to understand the experiences of carceral system-impacted students of color in …

Impact Of Black Shale Weathering On Stream Water And Sediment Quality In Eastern Kentucky, Brett Hopt

Dissertations and Theses

Black shales contain high concentrations of trace elements in addition to their elevated organic carbon content. Once exposed at the surface, weathering processes release these elements into the environment, including many (e.g., As, Cu, Cd, Cr, U, Zn) that could pose threats to human and environmental health. Previous studies have focused on how these metals are incorporated into the soil column and their effects on crop nutrition. However, few studies have focused on the impact of natural weathering of black shales on local stream water chemistry and the transport and subsequent partitioning of these geogenic contaminants into stream environments.

This …

Stayin' Alive (Even Without Oxygen): Retinal Development In Austrofundulus Limnaeus, Carmen Zecilia Rodriguez

Dissertations and Theses

The vertebrate eye is one of the most metabolically active organs in the body and is particularly sensitive to environmental stressors such as oxygen deprivation. Understanding how eye development proceeds under such conditions can provide critical insights into mechanisms of cellular resilience, tissue organization, and developmental plasticity. The annual killifish Austrofundulus limnaeus represents a unique model for investigating these processes due to its remarkable tolerance to anoxia during embryogenesis. However, the wild-type form is heavily pigmented, limiting the effectiveness of traditional imaging techniques for studying eye development. This thesis characterizes eye development and anoxia resilience in both wild-type and melanin-deficient …

Fathers' Racial Differences In Perceived Workplace-Induced Stereotype Threat: Impacts On Sense Of Belonging, Job Satisfaction, And Turnover, Frances Evalyne Kealiimahiaiokalani Hampton

Dissertations and Theses

Black fathers (BFs) face unique workplace challenges due to racialized and gendered stereotypes that undermine their legitimacy as men, workers, and parents. Drawing on Stereotype Threat Theory (STT) and Stereotype Embodiment Theory (SET), this study examined how workplace-induced stereotype threat (WIST) affects BFs' job attitudes and turnover intentions (TIs). I hypothesized that BFs would report higher WIST than White fathers (WFs), and that WIST would mediate the effects of race-related perceptions on job satisfaction (JS), sense of belonging (SOB), and TIs. In addition, perceived organizational support (POS) was tested as a moderator on the relationships between WIST and these job-related …

Controlling The Curriculum: A Content Analysis Of Prageru's Children's Educational Material, Heather Katherine Costa

Dissertations and Theses

PragerU is a conservative media outlet founded by Dennis Prager in 2009 that aims to insert new conservative content into existing U.S. public school curricula. While conservative activist groups have attempted for decades to alter educational content and policy, PragerU is attempting to directly influence public school curricula by having their materials authorized for use in public schools.

This study utilizes qualitative content analysis to understand the meaning behind PragerU's content, using a sample of 39 videos, targeted at students in grades 6 and higher. The transcript data were analyzed to address two research questions: 1) What are the key …

Understanding Long Covid In National Community-Based Cohort: Symptom Clusters, Symptom Natural History, And Vaccine’S Role As A Prevention Tool, Yanhan Shen

Dissertations and Theses

BACKGROUND: Long COVID, or post-acute sequelae of SARS-CoV-2 infection (PASC), represents a growing public health concern with diverse symptom profiles, unclear risk factors, and evolving evidence on potential prevention strategies. Most studies of Long COVID have relied on electronic health records or convenience samples, which may underestimate mild or community-based cases and lack standardized follow-up, and often do not include pre-infection health information or complete infection histories. This dissertation leverages prospective data from a national community-based cohort to characterize the heterogeneity of Long COVID symptoms, assess symptom trajectories over time, and evaluate the effect of COVID-19 third dose vaccination on …

The Social And Political Identities Of Latine Republicans In The U.S., Gabriella M. Mota

Dissertations and Theses

Between the 2016 and 2024 presidential elections, support for Republican candidate Donald Trump among Latine voters increased from 29% to 42%. This rise has attracted interest given Trump's nativist rhetoric and policies that target Latine immigrants. Previous literature has examined the growing Republican partisanship among Latine Americans, focusing on the processes of assimilation and the effects of racial ideology on the partisanship of the Latine electorate. Although this research is gaining traction, the political attitudes of Latine Republicans remain understudied. This study explores how Latine Republicans manipulate ethnoracial attachments to justify their support for Donald Trump and the Republican Party. …

Adapting To Southwest Idaho's Shifting Wildfire Regime: Sustainable Collaboration As A Means To Socioecological Resilience, Olivia Awbrey

Dissertations and Theses

Community wildfire adaptation is happening at multiple scales across the western United States. A range of collaboratively formed groups have addressed compounding issues related to wildfire risk, forest health and land use. In Southwestern Idaho, place-based collaboratives emerging in the early 2000s have considered trade-offs between localized social and ecological needs as they approach wildfire adaptation from the bottom-up. More recently, regional partnerships have emerged that emphasize cross-boundary wildfire risk reduction to cover larger geographic areas for risk mitigation. In between these micro- and macro-scales of activity exist bridging agencies such as county and state-level programs that account for gaps …