Digital Commons Network^™

Characterizing Rainfall Variability Within A Series Of Storms Over Northern California In February 2017, Parker Jan Malek

Dissertations and Theses

In February 2017, a series of storms with associated atmospheric rivers (ARs) made landfall in the US state of California, dropping large amounts of precipitation over the Sierra Nevada Mountains and their western foothills. The rainfall from these ARs, long, narrow bands of water vapor that transport large amounts of water vapor from the tropics to the mid-latitudes, instigated the near-failure of the Oroville Dam located at the southeastern edge of the Feather watershed outside the city of Oroville in the state's Central Valley. This case study provides a synoptic and mesoscale diagnosis of the drivers of rainfall pulses that …

Influence Of Inselbergs On Bat Diversity In Afrotropical Ecosystems, Amanda Lee Grunwald

Dissertations and Theses

Humans are altering biological communities on local to global scales, driving profound changes in biodiversity and ecosystem functioning. However, significant gaps and biases in biodiversity data hinder our understanding of ecosystem interactions, making it challenging to develop effective, data-driven policies to protect remaining biodiversity. Bats, the second most species-rich groups of mammals, have a global distribution, and perform a broad array of vital ecosystem functions. Their diversity peaks in the tropics, where they often constitute more than 50% of mammal species diversity. The Afrotropics host substantial bat diversity, yet have historically been perceived as having lower species richness compared to …

Layout-Aware Quantum Circuitry And Algorithmic Extensions To Grover's Algorithm, Ali Al-Bayaty

Dissertations and Theses

Lov K. Grover introduced, in 1996, Grover's algorithm as a quantum search algorithm to find all solutions for quantum oracles representing classical problems. My research observed that the Grover diffusion operator of Grover's algorithm gives wrong solutions when Boolean oracles are designed in some logical structures. Therefore, I invented the new "controlled-diffusion operator" for Boolean oracles as a new approach for Grover's algorithm that always correctly solves the problem of Grover's algorithm.

Another important problem in quantum computing is designing reliable and cost-effective quantum gates using reversible binary logic. In classical logic design, the stage of logic design can be …

Model Explanations For Gender And Ethnicity Bias Mitigation In Ai-Generated Narratives, Martha Otisi Dimgba

Dissertations and Theses

Large Language Models (LLMs) are increasingly utilized in diverse applications, ranging from professional content creation to decision-making systems. However, their outputs often amplify the biases present in their training data, perpetuating stereotypes and reinforcing societal inequities, particularly regarding gender and ethnicity. Such biases can cause tangible harm, especially for underrepresented groups, and require awareness and effective mitigation strategies.

This work explores gender and ethnicity representation in narratives created by generative AI describing 25 occupational fields defined by the U.S. Bureau of Labor Statistics. We examine three large language models (LLMs)--Llama 3.1 70B Instruct, Claude 3.5 Sonnet, and GPT 4.0 Turbo. …

Culturable Microbial Communities In Root Nodules Of Red Alder (Alnus Rubra Bong.) And Scotch Broom (Cytisus Scoparius L.): Patterns Of Diversity And Composition, Felisha (Fay) Rene Pooler

Dissertations and Theses

Endophytes are a hyper diverse group of bacterial or fungal organisms residing within plant tissues without causing visible symptoms of disease. While their overall diversity and ecological functions are not well-understood, some endophytes can provide a range of important benefits to their host such as enhanced growth and increased tolerance to environmental stress. Nitrogen-fixing bacteria residing within nodules--specialized structures on the roots of legumes and actinorhizal plants--play an integral role in the plant microbiome by facilitating nitrogen availability in nutrient-poor environments. Remarkably, the patterns of diversity including both bacterial and fungal endophytes in root nodules are virtually known, except in …

The Role Of Homocysteine Redox Chemistry In Biomolecular Mechanisms, Megha Gupta

Dissertations and Theses

Homocysteine at elevated levels is a well-known independent risk factor for cardiovascular disease. However, it is still unclear, after large scale clinical trials, involving tens of thousands of patients, whether homocysteine is a disease mediator or marker. The disconnect between the basic science showing the association of homocysteine with cardiovascular disease and the outcomes of clinical trials based on vitamin therapy for homocysteine lowering, highlights the need for insights into the molecular mechanisms linking homocysteine to cardiovascular disease and other pathologies. For example, elevated homocysteine levels have also been associated with risk for stroke, venous thromboembolism, Alzheimer's disease, neural tube …

Uncovering Moral Injury At Work: The Development And Initial Validation Of The Moral Injury At Work Scale (Miws), Megan J. Snoeyink

Dissertations and Theses

Employees frequently encounter situations at work that present moral or ethical dilemmas. Consequently, they may engage in immoral actions, witness moral violations, or fail to intervene when their coworkers behave immorally. Repeated exposure to such moral challenges can lead to moral injury--the damage to one's moral code and self-image resulting from witnessing, failing to prevent, or participating in what is perceived as an immoral act. Despite the potential for moral injury in workplace contexts, research has yet to adequately explore or measure this phenomenon. This dissertation addresses this gap by developing and validating the Moral Injury at Work Scale (MIWS). …

Becoming A Learner: An Autoethnography, Joshua Dickinson

Dissertations and Theses

It is well understood that attitudes toward language learning impact outcomes. This thesis uses autoethnography to explore the author's experiences learning German, in-class and independently, examining the interplay between motivation, attitudes, and the learning environment. I analyze personal journals and notes, employing graphic storytelling to illustrate their emotional journey. This paper draws upon existing literature on second language acquisition, particularly focusing on Dörnyei's L2 Motivational Self System and Ushioda's person-in-context approach. The study reveals how personal beliefs, self-doubt, and the limitations of traditional classroom settings impacted my motivation and ultimately, how reflection facilitated a renewed commitment to learning. In conclusion, …

Monitoring And Modeling Legacy Tree Response To Restoration Treatments In The Klamath Mountains, Oregon, Usa, Isaac Joseph Ball

Dissertations and Theses

Climate change and its disruption of historical drought and wildfire patterns pose a substantial threat to forest health in the western United States. This threat is compounded by past management practices like fire suppression. The largest, oldest, and most ecologically valuable trees are particularly vulnerable, making their conservation a key objective of climate-adaptive forest management. Restoration treatments such as mechanical thinning have been shown to enhance tree growth and drought resilience in dry conifer forests, but long-term monitoring is necessary to understand their sustained effects. This study used dendroecological tree-ring analysis to investigate the effects of thinning on the growth, …

Navigating The Neoliberal Assemblage: The Role Of A Nonprofit Organization Shaping Disaster Governance And Community Resilience, Andrew Michael Russo

Dissertations and Theses

This dissertation examines the evolving role of Nonprofits Active in Disasters ("NADs") in disaster governance through a case study of the Cascade Relief Team, a nonprofit organization responding to the 2020 Echo Mountain Complex Fire in Oregon. Utilizing governmentality and assemblage theory frameworks, the study investigates how CRT navigates the complex interplay between neoliberal rationalities, community needs, and disaster response practices.

The research reveals CRT's multifaceted role in shaping disaster knowledge, mediating between official frameworks and local realities, and influencing the formation of resilient subjectivities. While CRT's practices often align with neoliberal approaches to disaster management, emphasizing individual responsibility and …

Investigating Environmental Controls On Temperature Dynamics In An Urban Stream, Matthew Cullen Yates

Dissertations and Theses

Water temperature is a critical environmental variable influencing aquatic ecosystems. This study investigated the factors controlling stream temperature and thermal stratification in Rock Creek (RC) and Bethany Lake, an urbanized watershed featuring an in-line irrigation pond and buried wastewater infrastructure. Previous research suggested that subsurface water flow might drive temperature shifts in Rock Creek during summer periods when flow from Bethany Lake ceases. From 2023 to 2024, continuous temperature and stage monitoring, combined with statistical methods including principal component analysis and random forest regression, were used to evaluate seasonal temperature dynamics and their controlling factors. Results confirmed that seasonal reversals …

Commensality In The Eateries Of Roman Pompeii, Amaya Yolanda Eckersley

Dissertations and Theses

Despite a nearly 300-year excavation history at Pompeii and many identified eating and drinking establishments, social behavior in these public or semi-public spaces has eluded significant research. Elite Roman literature is the traditional guideline for understanding Roman mealtimes and what they meant for social behavior. This literature, however, fails to accurately represent its sub-elite inhabitants. These sub-elites of Rome largely had their meals prepared outside of their homes. Pompeii is no exception and provides a massive boon for researchers willing to consider archaeological evidence. The buildings and evidence buried at Pompeii have ultimately shown a wide array of tabernae related …

Shock Effects Including Maskelynite Formation In Three Shergottite Meteorites From Mars, George Ayeh Anim

Dissertations and Theses

Martian meteorites result from large impact events on the surface of Mars that cause intense shock metamorphism. This study examines the shock metamorphic features of three shergottite meteorites, Dho 019, NWA 12241, and NWA 15628, to better understand shock impact events. The research uses petrographic analysis, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and electron backscatter diffraction (EBSD) to analyze the meteorites. A key focus of this research is the formation of maskelynite, a glass with plagioclase composition, whose formation mechanism has been the substance of debate among researchers. This study proposes that maskelynite forms through a transient intermediary …

A Critical Appraisal Of Poverty In The Context Of Nature-Based Communities: Selected Cases From The Philippines, Carla Edith Gonzales Jimena

Dissertations and Theses

The Philippines is considered one of the wealthiest countries in both Southeast Asia and the world when measured by biodiversity, mineral resources and natural resources. It is also one of the most highly mineralized countries on earth. However, despite these natural endowments, when measured by established economic and human development indices the Philippines remains poor. Using critical perspectives derived from Marxist tradition, William Chambliss' theory of law and its dialectical nature, Immanuel Wallerstein's World Systems Theory, and Fred Block's structural mechanism of the state, this study aimed to critically appraise the persistence of poverty in nature-based communities in the Philippines. …

Photocathodes From Aerobic Oxidation Of Tellurorhodamines, Amelia Jellison

Dissertations and Theses

Growing environmental concerns have facilitated an increased need for renewable energy. Solar energy is an excellent source of renewable energy, however current dye-sensitized solar cells are not efficient enough for commercial use. This thesis attempts to create a novel dye-sensitized cathode to increase the efficiency of dye-sensitized solar cells.

Dye-sensitized cathodes could lower the energy level on the cathode and thereby increase the overall efficiency of the solar cell, however until now it has not been attempted. A tellurorhodamine dye with a mesityl ring was chosen as the dye for its ability to aerobically oxidize in the presence of light. …

Experiences Of Minority Workers: A Three-Study Dissertation Evaluating Recruitment And Workplace Experiences For Minority Workers, Jennifer Saucedo

Dissertations and Theses

Through a series of three manuscripts, the dissertation explores the experiences of minority groups across different points of the employee life cycle. As minority employees often face a negative set of unique stressors inside and outside of work, this series of papers attempt to further our understanding of minority experiences during the organizational stages of recruitment and retention. The first manuscript tests the effects of recruitment material on pre-hire applicant outcomes for minorities by integrating literature on realistic job previews (RJPs) and diversity recruitment. The experimental study finds that leader diversity testimonials that provide a mix of positive and negative …

Displaced: An Ethnography Of Language And Identity Loss, Ariel Caroline Wilsey-Gopp

Dissertations and Theses

Through ethnography and personal narrative, I explore the language and identity loss of one person, my father, in order to understand the complex issues surrounding the effects of symbolic and structural violence on language and identity development. Through personal narrative, fieldwork, and interviews, I tell the story of one person, born in wartime during Nazi occupied Serbia, and follow the guiding questions: how does language get lost and what are the effects? Drawing on methodology set forth by empirical ethnographical work as well as more recent theory around epigenetics and trauma, my research synthesizes into focus three pillars of understanding …

Youth Experiences Of Participation, Inclusion, And Influence Within A Youth-Serving Organization Implementing Participatory Processes, Rhen M. Miles

Dissertations and Theses

The youth development field has undergone shifts and reconstructions in how youth are conceived, impacting the approaches of youth-serving programs attempting to facilitate learning, growth, and engagement. Evolving views inform how policymakers, funders, and youth-serving agencies perceive and relate with youth. In turn, these dynamics influence how youth learn to think about themselves, others, and the world. Dominant discourse regarding youth development has been shifting from a deficit-based to an asset-based lens, with the proliferation of Positive Youth Development (PYD) frameworks, which seek to cultivate internal strengths and positive developmental outcomes rather than just prevent negative behaviors and outcomes. Despite …

"I'Ll Just Say It's Been A Racist Process": The Power Dynamics Within And Outside Diversity Requirement Classrooms At A Minority-Serving Institution, Kazusa Seko

Dissertations and Theses

U.S. higher educational institutions have increasingly implemented diversity requirements; however, institutional power dynamics during the implementation process and in a classroom after the implementation should be more highlighted. This study aims to understand the implementation of a diversity requirement during the implementation process and faculty and student experiences within required diversity courses at Portland State University (PSU) by analyzing one-on-one semi-structured interviews. PSU is a minority-serving educational institution that implemented a diversity requirement, the Race and Ethnic Studies Requirement (RESR), in Fall 2022. These data are analyzed through Critical Race Theory (CRT) lenses--introducing Okun's (2021) white supremacy culture in an …

Structural Earthquake Resiliency Of Rocking Core Systems With Floor Enabled Recentering, S. Taban Hajimirza

Dissertations and Theses

The growing need for structural earthquake resiliency, coupled with increasing demands for environmentally sustainable construction, has driven architects and engineers to emphasize the importance of earthquake-resistant mass timber multistory construction in regions prone to high seismic activity. With advancements in building technologies, cross-laminated timber (CLT) has emerged at the forefront of this movement by unlocking new potentials for urban development.

Motivated by the aforementioned demands, this PhD dissertation investigated lateral behavior and earthquake response of a novel lateral force-resisting structural system, known as Floor Recentering Rocking Core (FLR-ROCR). FLR-ROCR is a low-damage recentering mass-timber system that leverages restoring interactions between …

Tree-Equity And Environmental Justice Discourses Among Urban Forestry Professionals In Portland: Current Impacts And Future Implications, Axcelle Deone Bell

Dissertations and Theses

Urban tree equity is critical for addressing environmental justice and mitigating the effects of climate change in cities. This study investigates how professionals in Portland's urban forestry sector conceptualize and implement tree equity, focusing on equity and justice discourses. Through 27 semi-structured interviews with 29 professionals from government agencies and NGOs, I examine how these discourses shape decisions regarding tree planting, distribution, and maintenance, particularly in underserved communities. The analysis draws on political ecology, systems dynamics, and structuration theory to explore the systemic barriers perpetuating inequities in tree canopy distribution. The findings reveal tensions between different approaches to equity, such …

Forest Fires Increase Mid-Winter Snowmelt In The Western Oregon Cascades, Sage Ebel

Dissertations and Theses

As the spatiotemporal overlap between burned forests, seasonal snow, extreme precipitation, and mid-winter warming continues to increase with climate change, it is critical we quantify the impacts of forest fires and rain-on-snow (ROS) on mid-winter snowmelt and snow-water resources. In the Pacific Northwest, the release of large volumes of meltwater to downstream receiving water from already vulnerable snowpacks can have catastrophic consequences. I show that forest fires doubled mid-winter snowmelt proportions as compared to unburned reference sites, using a novel network of snow monitoring and micrometeorological stations installed across an elevational and forest type gradient in a burned watershed in …

Integrative Approaches To Climate Resilience Planning: Application Of A Plan Evaluation Framework, Maulsri Jha

Dissertations and Theses

In the last two decades, urban governments have streamlined and prioritized the creation and implementation of climate resilience plans to cater to the communities' vulnerabilities. Existing research illustrates that there is a gap in understanding how, or if, empirical (evidence-based) data are incorporated into the design and implementation of such plans and the extent to which their inclusion impacts outcomes in terms of vulnerability reduction. There is also a gap in the systematic study of their outcomes in terms of community resilience, and whether equity and environmental justice are promoted as priorities.

The purpose of the research is to understand …

Turbulent Structures In Coupled Wind-Wave Flows, Cerrina Mouchref

Dissertations and Theses

The interactions between wind and waves in offshore environments are complex and have yet to be fully understood. Analyzing these interactions is motivated by an increased interest in climate modeling and the deployment of offshore construction, such as offshore wind farms. In this study, experiments are performed in a wind tunnel using particle image velocimetry (PIV) to analyze wind-wave interactions over various wave and wind speeds. The addition of the wave, a moving boundary, leads to the use of Reynolds triple decomposition in order to separate the turbulent and wave-phase coherent fluctuations. A curvilinear coordinate system was used to analyze …

Recruitment, Reprogramming, And Function Of Trpv1+ Sensory Nerves In The Development And Progression Of Head And Neck Cancer, Anthony Restaino

Dissertations and Theses

Head and neck squamous cell carcinomas (HNSCC) are an epithelial cancer prevalent across the world and are divided into two subcategories: human papillomavirus-mediated (HPV+) and carcinogen-mediated (HPV-) HNSCC. These subgroups have distinct patient populations, divergent responses to therapy, and prognoses, however the foundational mechanisms that facilitate these differences are not well understood or defined. Recently, the presence and function of sensory neurons within the tumor environment of various solid tumors has been identified and investigated. Herein, we identify differences in the presence of TRPV1+ sensory neurons and neuron structures in the tumor environment of HPV+ and HPV- HNSCC, correlating with …

Unveiling Universal Mental Health Screening: School Psychologists’ Perspectives, Practices, And The Role Of Demographics, Gracie Taylor Hansen

Dissertations and Theses

The critical need to address mental health problems among children, combined with the increasing emphasis on universal mental health screening in school settings, underscores the importance of understanding demographic influences on these measures. This study examined the impact of demographic variables, particularly race and ethnicity, on the use, reliability, and validity of universal mental health screening tools. The Behavior Assessment System for Children, Third Edition Behavioral and Emotional Screening System (BASC-3 BESS) was used to collect screening data. Utilizing a mixed-methods approach, the research comprised two components. First, a survey, developed by the researcher, was administered to school psychologists to …

Perceptions Of Artificial Intelligence Use To Enhance Feedback For Preservice Teachers During Field Experiences, Betsy Schamber

Dissertations and Theses

University supervisors (USs) play a key role in providing feedback for preservice teachers (PSTs). Although artificial intelligence (AI)’s use in providing feedback in educational settings had been explored, its use for feedback for PSTs’ field experience remained unknown. The first case study herein explores PSTs’ perceptions of AI-assisted feedback for field experiences. Findings highlighted PSTs’ perceptions of AI as a catalyst for new idea generation. While AI provided a starting point, the ending output still needed to reflect PSTs’ personalities. Similarly, PSTs valued the human element of feedback, noting how USs’ lived experiences provided an added value. In K–12 classrooms, …

The Role Of Grades On Learning In Higher Education, Kindra Schneider

Dissertations and Theses

This study examines grading in higher education from two distinct perspectives: graduate students’ perceptions of a grading scheme that utilizes rubrics and self-assessment and instructors’ perceptions of academic freedom in grading. The first study examined graduate students’ perspectives on a grading scheme utilizing rubrics and self-assessment. Data from focus groups and journals revealed four main themes: the importance of clear expectations, enhanced synergy between rubrics and self-assessment when transparency increased, bias towards rubrics based on more exposure, and mixed feelings surrounding perceptions of self-assessment and its influence on learning. The second study investigated non-tenured faculty’s perceptions of academic freedom in …

Social Anxiety And Cannabis Use Context, Brooke Beckius

Dissertations and Theses

Cannabis use is highly prevalent among young adults in the United States, with many experiencing associated problems. Social anxiety has been identified as a significant risk factor for cannabis use and related consequences; however, it remains unclear whether cannabis facilitates or inhibits social engagement among socially anxious individuals. Solitary cannabis use is consistently linked to use-related problems, but the term “solitary use” may encompass distinct contexts—such as social preparatory use, use to aid sleep, or use while spending time alone. The present study aimed to examine how cannabis use influences social engagement among socially anxious individuals and test how specific …

Will This Be Graded? A Multiple Case Study Analysis Of High School Principals’ And Teachers’ Grading Beliefs, Adam Rudebusch

Dissertations and Theses

This dissertation examined the beliefs and perceptions of high school teachers and principals in two rural, Midwestern states to discover what they believed about the purpose and process of determining students’ grades. The aim of the research was to discover the discrepancies between stakeholders’ beliefs about grading and the implications of these discrepancies for policy and practice. A qualitative approach involving one focus group comprised of four principals, one focus group of four teachers, and two follow-up interviews with individual teachers was used to discover teachers’ and principal’s beliefs surrounding grades. Protocols included both direct questions and vignettes that allowed …