Physical Sciences and Mathematics Commons^™

Unremarkable To Remarkable Ai Agent: Exploring Boundaries Of Agent Intervention For Adults With And Without Cognitive Impairment, Mai Lee Chang, Samantha Reig, Alicia (Hyun Jin) Lee, Anna Huang, Hugo Simão, Nara Han, Neeta M. Khanuja, Abdullah Ubed Mohammad Ali, Rebekah Martinez, John Zimmerman, Jodi Forlizzi, Aaron Steinfeld

Computer Science Faculty Publications and Presentations

As the population of older adults increases, there is a growing need for support for them to age in place. This is exacerbated by the growing number of individuals struggling with cognitive decline and shrinking number of youth who provide care for them. Artificially intelligent agents could provide cognitive support to older adults experiencing memory problems, and they could help informal caregivers with coordination tasks. To better understand this possible future, we conducted a speed dating with storyboards study to reveal invisible social boundaries that might keep older adults and their caregivers from accepting and using agents. We found that …

Glacial-Interglacial And Millennial-Scale Changes In Nitrous Oxide Emissions Pathways And Source Regions, J. A. Menking, J. E. Lee, E. J. Brook, J. Schmitt, L. Soussaintjean, H. Fischer, J. Kaiser, A. Rice

Physics Faculty Publications and Presentations

During the transition from the Last Glacial Maximum (LGM) to the Holocene, the atmospheric N2O mole fraction increased by 80 nmol mol−1. Using ice core measurements of N2O isotopomer ratios, we show that this increase was driven by increases in both nitrification and denitrification, with the relative partitioning between both production pathways depending on the assumed isotopic end‐member source signatures. Similarly, we also attribute a 35 nmol mol−1 N2O mole fraction increase during the Heinrich Stadial 4/Dansgaard Oeschger 8 (HS4/DO8) millennial‐scale event to increases in both N2O production pathways. In contrast, the 25 nmol mol−1 N2O mole fraction decrease during …

Estimated Amounts Of Terrestrial Carbon Mobilized And Sequestered By The 1980 Mount St. Helens Eruption, Washington State, Usa, Lizzet G. Reyes

Dissertations and Theses

Volcanic eruptions significantly influence the geologic carbon cycle by emitting CO₂ and mobilizing terrestrial carbon pools. The 1980 Mount St. Helens (MSH) eruption offers a unique case study, triggering a massive landslide that displaced 2.7 km³ of sediment, buried 600 km² of forest, and disrupted regional carbon dynamics. Pre-eruption terrestrial carbon stocks, including aboveground biomass (AGB), dead biomass (D), and soil organic carbon (S), averaged 209.5 tC/ha. Post-eruption, total carbon density fell to 118.7 tC/ha, driven mainly by a 51% reduction in AGB, modest declines in D, and redistribution of S. Over 36 years, ecosystem recovery increased …

Assessing The Potential For A Novel Composite Integrative Passive Sampler (Cips) To Investigate Transboundary Movement Of Organic Chemicals In The Tijuana River Estuary., Zuying Feng, Flannery Mclamb, Damian Shea, Kesten Bozinovic, Chris Stransky, Richard M. Gersberg, Wenling Wang, Xiang Kong, Xin-Rui Xia, Miguel F. Vasquez, Mackenzie King, Goran Bozinovic

Center for Life in Extreme Environments Publications

Nearly all environmental monitoring and research of chemical exposure in the aquatic environment relies on grab sampling of water and/or sediment providing only a snapshot in time. Passive sampling of water provides a more representative estimate of exposure compared to grab sampling, but current passive samplers have a limited working range of chemical properties. We tested a novel Composite Integrative Passive Sampler (CIPS) that simultaneously accumulates both hydrophobic and hydrophilic chemicals in water in the Tijuana River Estuary (TRE) on the U.S.-Mexico border. Quantitative targeted analysis detected 169 of the 193 targeted chemicals, and 128 of them were detected in …

The Geologic History Of The Chehalis Forearc Basin, Washington State, Usa, Rud Lamb Moe

Dissertations and Theses

The Chehalis Basin, in southwest Washington, is one of a series of forearc basins between the Cascade Arc and the Coast Range in the Pacific Northwest. While the Seattle basin to the north, and the Portland-Tualatin basins to the south are both relatively well studied, the geologic evolution of basins in between is poorly constrained. The Chehalis basin is underlain by accreted Eocene oceanic basalt of the Crescent Formation. The basin fill consists of sedimentary rocks and volcanic rocks deposited throughout the Cenozoic. It has undergone N-S shortening driven by transpressional stress from oblique subduction of the Juan de Fuca …

Development Scenarios And Wildfire Risk In Central Oregon, Samantha Hall

Dissertations and Theses

Risk from natural hazards occurs where areas vulnerable to natural hazards and development intersect. Development in vulnerable areas is a societal choice that has a lasting impact as our built environment is relatively permanent. Development patterns that contribute to increased wildfire risk mostly occur within the wildland urban interface, a land use type where development is at the fringes or intercept of wildland areas and is more flammable due to surrounding vegetation, slope, local climate, and other factors. To understand how past and future development potentials may impact fire risk in wildfire prone areas, a case study of Deschutes County, …

Perceptions About Potential Microplastic Interventions: A Study On Knowledge, Concerns, And Willingness To Pay, Amanda Gannon, Elise F. Granek, Max Nielsen-Pincus, Luke Harkins

Environmental Science and Management Faculty Publications and Presentations

Among emerging contaminants, microplastics (MPs) are of particular concern due to their ubiquity across environments and the unique challenges posed by attempted removal. In-line washing machine filters are one potential tool for preemptively preventing a category of MPs from entering waterways. A sample of registered voters and environmental interest groups in Oregon were asked about their general knowledge and concerns surrounding microplastics, as well as their willingness to pay for high-efficiency washing machine filters. Findings show that less than a quarter of all respondents would be willing to pay full price for a high-efficiency filter, indicating a limited-scale early adopter …

Investigating Key Structures In Protective Scenes For Llms, Eben M. Weisman

University Honors Theses

This research delves into the realm of "protective scenes" within Large Language Models (LLMs), exploring their impact on bias mitigation, deception, and context preservation. The study investigates the use of roleplay prompting human-like behavior and reasoning in LLMs, focusing on the Character-LLM framework's concept of protective scenes with graduated levels of protection. By combining insights from psychology, cognitive science, and computational analysis, this research aims to develop a framework for understanding how protective scenes influence roleplay performance in LLMs, ultimately contributing to the development of more reliable and ethical AI systems.

Abiotic Variables Drive Different Aspects Of Fish Community Trait Variation And Species Richness Across The Continental United States, Alicia Mcgrew, Crysta Gantz, Brigid Wills, Benjamin Baiser, Sydne Record, Phoebe L. Zarnetske, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

Intraspecific trait variation (ITV) is an increasingly important aspect of biodiversity and can provide a more complete perspective on how abiotic and biotic processes affect individuals, species' niches and ultimately community-level structure than traditional uses of trait means. Body size serves as a proxy for a suite of traits that govern species' niches. Distributions of co-occurring species body sizes can inform niche overlap, relate to species richness and uncover mechanistic drivers of diversity. We leveraged individual-level body size (length) in freshwater fishes and environmental data from the National Ecological Observatory Network (NEON) for 17 lakes and streams in the contiguous …

Near Convexity And Generalized Differentiation, Nguyen Mau Nam, Nguyen Nang Thieu, Nguyen Dong Yen

Mathematics and Statistics Faculty Publications and Presentations

In this paper, we introduce the concept of nearly convex set-valued mappings and investigate fundamental properties of these mappings. Additionally, we establish a geometric approach for generalized differentiation of nearly convex set-valued mappings and nearly convex functions. Our contributions expand the current knowledge of nearly convex sets and functions, while providing several new results pertaining to nearly convex set-valued mappings.

Adaptive Resolution Of Fine Scales In Modes Of Microstructured Optical Fibers, Jay Gopalakrishnan, Jacob Grosek, Gabriel Pinochet-Soto, Pieter Vandenberge

Mathematics and Statistics Faculty Publications and Presentations

An adaptive algorithm for computing eigenmodes and propagation constants of optical fibers is proposed. The algorithm is built using a dual-weighted residual error estimator. The residuals are based on the eigensystem for leaky hybrid modes obtained from Maxwell equations truncated to a finite domain after a transformation by a perfectly matched layer. The adaptive algorithm is then applied to compute practically interesting modes for multiple fiber microstructures. Emerging microstructured optical fibers are characterized by complex geometrical features in their transverse cross section. Their leaky modes, useful for confining and propagating light in their cores, often exhibit fine-scale features. The adaptive …

Indigenous Futures: Decolonizing Conservation And Restoring Ecological Sovereignty, Jasmine Beach

University Honors Theses

This study examines how members of Indigenous-led conservation organizations perceive the ecological and social implications of colonial conservation ideologies in the context of contemporary grassroots strategies. By analyzing the ongoing impact of conservation frameworks in Kenya, this research highlights the role of Indigenous-led initiatives in advancing sustainable, community-driven alternatives. Using a Two-Eyed Seeing approach, which integrates Traditional Ecological Knowledge (TEK) with Western scientific methods, the study employs qualitative, semi-structured interviews with leaders from Zawadisha, KENVO, Wildlife Works, and CER-Kenya. Findings indicate that these organizations, particularly those led by women, actively restore biodiversity, enhance climate resilience, and challenge exclusionary conservation policies. …

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 …

Neural Visual Synthesis For Graphics, 4d Gaussians And Videos, Zhan Li

Dissertations and Theses

Efficient visual synthesis has played an indirect yet important role in the development of neural networks. Graphics processing units (GPUs) were initially designed for visual synthesis tasks such as rendering graphics. However, their parallel computing capabilities later made GPUs the ideal hardware for training neural networks. Since neural networks have greatly benefited from GPUs, a compelling question arises: How can neural networks, in turn, improve efficient visual synthesis?

Existing visual synthesis methods still require improvement for higher efficiency. For example, Monte Carlo rendering takes over 15 minutes to generate a megapixel frame at a high-quality setting on a GPU, as …

Next Arrival And Destination Prediction Via Spatiotemporal Embedding With Urban Geography And Human Mobility Data, Pengjiang Li, Zaitian Wang, Xinhao Zhang, Pengfei Wang, Kunpeng Liu

Computer Science Faculty Publications and Presentations

With the development of transportation networks, countless trajectory data are accumulated, and understanding human mobility from traffic data could be helpful for smart cities, urban computing, and urban planning. Extracting valuable insights from traffic data, such as taxi trajectories, can significantly improve residents’ daily lives. There are many studies on spatiotemporal data mining. As we know, arrival prediction or regional function detection encompasses important tasks for traffic management and urban planning. However, trajectory data are often mutilated because of personal privacy and hardware limitations, i.e., we usually can only obtain partial trajectory information. In this paper, we develop an embedding …

Extant Life Detection Using Label-Free Video Microscopy In Analog Aquatic Environments, Carl D. Snyder, Manuel Bedrossian, Casey Barr, Jody W. Deming, Chris A. Lindensmith, Christian Stenner, Jay L. Nadeau

Physics Faculty Publications and Presentations

The ability of microbial active motion, morphology, and optical properties to serve as biosignatures was investigated by in situ video microscopy in a wide range of extreme field sites where such imaging had not been performed previously. These sites allowed for sampling seawater, sea ice brines, cryopeg brines, hypersaline pools and seeps, hyperalkaline springs, and glaciovolcanic cave ice. In all samples except the cryopeg brine, active motion was observed without any sample treatment. Active motion was observed in the cryopeg brines when samples were subjected to a temperature gradient above in situ. In general, levels of motility were low in …

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. …

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 …

Lagging Brain Gene Expression Patterns Of Drosophila Melanogaster Young Adult Males Confound Comparisons Between Sexes, Flannery Mclamb, Zuying Feng, Jeanne P. Vu, Lindsey Griffin, Miguel F. Vasquez, Goran Bozinovic

Center for Life in Extreme Environments Publications

Many species, including fruit flies (Drosophila melanogaster), are sexually dimorphic. Phenotypic variation in morphology, physiology, and behavior can affect development, reproduction, health, and aging. Therefore, designating sex as a variable and sex-blocking should be considered when designing experiments. The brain regulates phenotypes throughout the lifespan by balancing survival and reproduction, and sex-specific development at each life stage is likely. Changes in morphology and physiology are governed by differential gene expression, a quantifiable molecular marker for age- and sex-specific variations. We assessed the fruit fly brain transcriptome at three adult ages for gene expression signatures of sex, age, and sex-by-age: 6698 …

Plural Water Narratives: An Environmental Justice Lens On A Systematic Review Of Q-Methodology Water Research, Melissa Haeffner, Alida Cantor, Janet Cowal, Andrea Bryant, Darius Mani Yaw, Kinna Je Palacios, Daniela Serna, Bryce Sprauer, Abigail Tran-Gruver

Environmental Science and Management Faculty Publications and Presentations

Environmental justice research has shown that people's experiences and perceptions of water differ because systematic inequalities shape the extent to which people access clean water and are exposed to water hazards. Q‐methodology is one technique that has been used to aggregate multifaceted subjective narratives and understand different perspectives on a topic. In this paper, we systematically review 77 case study articles applying Q‐methodology to water‐related topics, to inventory how people perceive their relationships with water. We create a classification system based on environmental justice theory to examine (1) distributive justice issues around alternative water sources and agricultural and urban water …

The Effects Of Imidacloprid And Polyester Microfibers On The Larval Development Of The Endangered Sunflower Star, Alexandra G. Tissot, Elise F. Granek, Fiona Curliss, Augustin Kalytiak-Davis, Jason Hodin, Michelle L. Hladik

Environmental Science and Management Faculty Publications and Presentations

Sea star wasting syndrome has affected numerous species of sea star, with populations of Pycnopodia helianthoides (Brandt, 1835) left most at risk. As their populations are struggling to recover, it is important to gain a better understanding of the impacts that the multiple stressors in their habitats can have on their populations. Contaminant stressors in particular are of increasing importance, because aquatic organisms can be exposed to a dynamic range of contaminants from nearby anthropogenic activity that may affect their future recovery efforts. This study is the first to quantify the effects of contaminant stressors on the larvae of P. …

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 …

Access To Arynes From Arenes Via Net Dehydrogenation: Scope, Synthetic Applications And Mechanistic Analysis, Riley A. Roberts, Bryan E. Metze, Nicole Javaly, Theresa M. Mccormick, David R. Stuart

Chemistry Faculty Publications and Presentations

Arynes undergo a wide range of chemical transformations making them versatile reactive intermediates for organic synthesis. Access to arynes has long been dominated by pre-functionalised reagents, e.g., the venerable o-trimethylsilylaryl triflates. However, a move toward developing methods to access arynes that are both mild and efficient has prompted research into aryl “onium” aryne precursors. Here, we leverage aryl “onium” species as in situ or isolated intermediates in a net dehydrogenation of simple arenes as a novel and efficient way to access arynes. We describe a unified strategy in which two different tactics are employed to access diversely substituted …

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 …

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. …

Understanding Anionic Hyperporphyrins: Tddft Calculations On Peripherally Deprotonated Meso-Tetrakis(4-Hydroxyphenyl)Porphyrin., Jeanet Conradie, Carl C. Wamser, Abhik Ghosh

Chemistry Faculty Publications and Presentations

Presented herein is a DFT/TDDFT study of -tetrakis(4-hydroxyphenyl)porphyrin (H[THPP]) and its Meso-deprotonated tetraanionic form; the latter was modeled as both a free tetraanion and with various counterions. Based on our calculations, the experimentally observed hyperporphyrin spectra are attributed to an admixture of phenol/phenoxide character into the a-type HOMO of tetraphenylporphyrin. The admixture results in an elevation of the orbital energy of the HOMO in relation to other frontier orbitals, which accounts for the observed spectral redshifts. The calculations underscore differences in the performance of different exchange-correlation functionals. Thus, while the popular hybrid functional B3LYP greatly exaggerates the redshift of …

Oregon State Rank Assessment For Transparent Milk-Vetch (Astragalus Daphanus Var. Diaphanus), Nora Dunkirk, Gabriel Campbell

Institute for Natural Resources Publications

Oregon state conservation status assessment for Transparent Milk-vetch (Astragalus daphanus var. diaphanus) using NatureServe methodology, 2025.

3F4 Hypergeometric Functions As A Sum Of A Product Of 1F2 Functions, Jack C. Straton

Physics Faculty Publications and Presentations

This paper shows that certain ₃F₄ hypergeometric functions can be expanded in sums of pair products of ₁F₂ functions. In special cases, the ₃F₄ hypergeometric functions reduce to ₂F₃ functions. Further special cases allow one to reduce the ₂F₃ functions to ₁F₂ functions, and the sums to products of ₀F₁ (Bessel) and ₁F₂ functions. The class of hypergeometric functions with summation theorems are thereby expanded beyond those expressible as pair-products of ₂F₁ functions, ₃F₂ functions, and generalized Whittaker functions, into …

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 …