Physical Sciences and Mathematics Commons^™

Major Controls On Diagenesis In The Martin Bridge Formation: Wallowa Mountains, Oregon, Jane Lyra Eisenberg

Dissertations and Theses

Diagenetic alteration in carbonates has long frustrated scientists who wish to use their chemistry and/or texture to understand conditions at the time of deposition. Though indicators of diagenesis are well documented, their interpretation is not always straightforward. Despite the large volume of research on the subject, the positive identification and interpretation of diagenesis is a source of ongoing debate in the scientific community.

The goal of this study is to better understand the timing of, and controls on, diagenetic alteration in the Martin Bridge Formation (MBF), a Triassic-aged limestone that was altered following deposition. Thirty-nine samples of MBF with differing …

Convergence Analysis Of Some Tent-Based Schemes For Linear Hyperbolic Systems, Dow Drake, Jay Gopalakrishnan, Joachim Schöberl, Christoph Wintersteiger

Mathematics and Statistics Faculty Publications and Presentations

Finite element methods for symmetric linear hyperbolic systems using unstructured advancing fronts (satisfying a causality condition) are considered in this work. Convergence results and error bounds are obtained for mapped tent pitching schemes made with standard discontinuous Galerkin discretizations for spatial approximation on mapped tents. Techniques to study semidiscretization on mapped tents, design fully discrete schemes, prove local error bounds, prove stability on spacetime fronts, and bound error propagated through unstructured layers are developed.

Selenium Probes For The Detection Of Thioredoxin Reductase Activity, Tendai Joseph Mafireyi

Dissertations and Theses

The identification and quantification of proteins and enzymatic activity in living tissues frequently requires the use of invasive procedures such as biopsy. These techniques can inhibit measurements of protein levels in real-time, and the disruption of tissue can lead to the loss of important information concerning the spatial distribution and differential activities in various cell types. The use of small organic fluorescent probes that rely on activation or accumulation within a tissue embody robust methods of detection that address these issues. This dissertation describes the design, synthesis and evaluation of fluorescent probes that can detect the enzyme thioredoxin reductase (TrxR). …

Forest Fire Effects On The Temporal Variability Of Landscape Snow Albedo Relative To Burn Severity, Max Gersh

Dissertations and Theses

Snow-water storage is decreasing, while forest fires are increasing in duration, size, frequency, and intensity, due to climate change. Most forest fires occur in the seasonal snow zone, altering snow mass and energy balance for many years following fire. Following forest fires, Surface snow albedo (SSA) decreases, as light absorbing particles (LAP), particularly black carbon (BC) produced in forest fires get deposited throughout the snowpack, altering snowpack energy balance driving earlier snowmelt in burned forests. While SSA decreases, landscape snow albedo (LSA) increases following fire, as more of the snow-covered surface becomes visible beneath the burned forest canopy, brightening the …

Efficient Neuromorphic Algorithms For Gamma-Ray Spectrum Denoising And Radionuclide Identification, Merlin Phillip Carson

Dissertations and Theses

Radionuclide detection and identification are important tasks for deterring a potentially catastrophic nuclear event. Due to high levels of background radiation from both terrestrial and extraterrestrial sources, some form of noise reduction pre-processing is required for a gamma-ray spectrum prior to being analyzed by an identification algorithm so as to determine the identity of anomalous sources. This research focuses on the use of neuromorphic algorithms for the purpose of developing low power, accurate radionuclide identification devices that can filter out non-anomalous background radiation and other artifacts created by gamma-ray detector measurement equipment, along with identifying clandestine, radioactive material.

A sparse …

Catastrophic Beach Sand Losses Due To Erosion From Predicted Future Sea Level Rise (0.5–1.0 M), Based On Increasing Submarine Accommodation Spaces In The High-Wave-Energy Coast Of The Pacific Northwest, Washington, Oregon, And Northern California, Usa, Curt D. Peterson, Don Joseph Pettit, Kara E. P. Kingen, Sandy Vanderburgh, Chuck Rosenfeld

Geology Faculty Publications and Presentations

The U.S. Pacific Northwest (PNW) coastline (1000 km) has been analyzed for conditions that could impact beach erosion from potential near-future (100 year) sea level rise (SLR). Heavy mineral analysis of river, beach, and shelf samples (n = 105) establish the sources of the beach deposits. River bedload discharge and intervening estuarine sinks for river sand supplies (n = 31) were normalized to the one century time interval. Twenty-six subcell beaches (657 km in combined length) were surveyed (153 profiles) for beach sand widths (20–412 m) and sand cross-sectional areas (20–1810 m2 ) above wave-cut platforms and/or 0 m tidal …

Rotten Green Tests In Java, Pharo And Python, Vincent Aranega, Julien Delplanque, Matias Martinez, Andrew P. Black, Stéphane Ducasse, Anne Etien, Christopher Fuhrman, Guillermo Polito

Computer Science Faculty Publications and Presentations

Rotten Green Tests are tests that pass, but not because the assertions they contain are true: a rotten test passes because some or all of its assertions are not actually executed. The presence of a rotten green test is a test smell, and a bad one, because the existence of a test gives us false confidence that the code under test is valid, when in fact that code may not have been tested at all. This article reports on an empirical evaluation of the tests in a corpus of projects found in the wild. We selected approximately one hundred mature …

Rhyolite Stratigraphy Along Succor Creek: Insights Into The Eruptive History Of The Three Fingers And Mahogany Mountain Volcanic Field, Cassandra Caryl Black

Dissertations and Theses

The Mahogany Mountain and Three Fingers calderas with their associated tuffs, the tuff of Leslie Gulch and tuff of Spring Creek, respectively, were the centerpiece of a larger rhyolite center that developed in response to Columbia River Basalt volcanism as numerous other mid Miocene rhyolite centers in a corridor from Baker City in the north to northern Nevada. Previous studies suggest a two caldera model, while others advocated for a single large caldera producing solely the tuff of Leslie Gulch. This study refines the eruptive stratigraphy along the northeastern margin of this rhyolite field with important implications for the entire …

Investigation Of Environmental-Friendly, Membraneless Hydrogen Peroxide Fuel Cells, Bao Nguyen

Dissertations and Theses

Human-induced climate change is one of the biggest threats to humanity in the 21^st century. This is caused by the increase in greenhouse gas concentrations in the Earth's atmosphere. The burning of fossil fuels is the primary cause of climate change. This problem can be addressed by replacing fossil fuels with fuel sources that have clean by-products and are cost-effective. For the last few decades, hydrogen (H₂) has been extensively studied as an alternative to carbon-based fossil fuels. Currently, H₂ still has many shortcomings for commercial applications. The photocatalytic production of H₂ still suffers from …

Balanced Polymorphism Fuels Rapid Selection In An Invasive Crab Despite High Gene Flow And Low Genetic Diversity., C K. Tepolt, E D. Grosholz, Catherine E. De Rivera, G M. Ruiz

Environmental Science and Management Faculty Publications and Presentations

Adaptation across environmental gradients has been demonstrated in numerous systems with extensive dispersal, despite high gene flow and consequently low genetic structure. The speed and mechanisms by which such adaptation occurs remain poorly resolved, but are critical to understanding species spread and persistence in a changing world. Here, we investigate these mechanisms in the European green crab Carcinus maenas, a globally distributed invader. We focus on a northwestern Pacific population that spread across >12 degrees of latitude in 10 years from a single source, following its introduction 1,500 km, we examine genetic structure using 9,376 Single Nucleotide Polymorphisms (SNPs). We …

Simulating Dislocation Densities With Finite Element Analysis, Ja'nya Breeden, Dow Drake, Saurabh Puri

REU Final Reports

A one-dimensional set of nonlinear time-dependent partial differential equations developed by Acharya (2010) is studied to observe how differing levels of applied strain affect dislocation walls. The framework of this model consists of a convective and diffusive term which is used to develop a linear system of equations to test two methods of the finite element method. The linear system of partial differential equations is used to determine whether the standard or Discontinuous Galerkin method will be used. The Discontinuous Galerkin method is implemented to discretize the continuum model and the results of simulations involving zero and non-zero applied strain …

Forest Park Trail Monitoring, Adan Robles, Colton S. Maybee, Erin Dougherty

REU Final Reports

Forest Park, one of the largest public parks in the United States with over 40 trails to pick from when planning a hiking trip. One of the main problems this park has is that there are too many trails, and a lot of the trails extend over 3 miles. Due to these circumstances’ trails are not checked frequently and hikers are forced to hike trails in the area with no warnings of potential hazards they can encounter. In this paper I researched how Forest Park currently monitors its trails and then set up a goal to solve the problem. We …

Spatial Analysis Of Landscape Characteristics, Anthropogenic Factors, And Seasonality Effects On Water Quality In Portland, Oregon, Katherine Gelsey, Daniel Ramirez

REU Final Reports

Urban areas often struggle with deteriorated water quality as a result of complex interactions between landscape factors such as land cover, use, and management as well as climatic variables such as weather, precipitation, and atmospheric conditions. Green stormwater infrastructure (GSI) has been introduced as a strategy to reintroduce pre-development hydrological conditions in cities, but questions remain as to how GSI interacts with other landscape factors to affect water quality. We conducted a statistical analysis of six relevant water quality indicators in 131 water quality stations in four watersheds around Portland, Oregon using data from 2015 to 2021. Indiscriminate of station …

Digitally Reporting Trail Obstructions In Forest Park, Colton S. Maybee

REU Final Reports

The inclusion of technology on the trail can lead to better experiences for everyone involved in the hobby. Hikers can play a more prominent role in the maintenance of the trails by being able to provide better reports of obstructions while directly on the trail. This paper goes into the project of revamping the obstruction report system applied at Forest Park in Portland, Oregon. Most of my contributions to the project focus on mobile app development with some research into path planning algorithms related to the continuations of this project.

Client Access Feature Engineering For The Homeless Community Of The City Of Portland, Oswaldo Ceballos Jr

altREU Projects

Given the severity of homeless in many cities across the country, the project at hand attempts to assist a service provider organization called Central City Concern (CCC) with their mission of providing services to the community of Portland. These services include housing, recovery, health care, and jobs. With many different types of services available through the works of CCC, there exists an abundance of information and data pertaining to the individuals that interact with the CCC service system. The goal of this project is to perform an exploratory analysis and feature engineer the existing datasets CCC has collected over the …

E-Cigarette Fluids And Aerosol Residues Cause Oxidative Stress And An Inflammatory Response In Human Keratinocytes And 3d Skin Models., Careen Khachatoorian, Wentai Luo, Kevin J. Mcwhirter, James F. Pankow, Prue Talbot

Chemistry Faculty Publications and Presentations

Our goal was to evaluate the effects of EC refill fluids and EC exhaled aerosol residue (ECEAR) on cultured human keratinocytes and MatTek EpiDerm™, a 3D air liquid interface human skin model. Quantification of flavor chemicals and nicotine in Dewberry Cream and Churrios refill fluids was done using GC-MS. The dominant flavor chemicals were maltol, ethyl maltol, vanillin, ethyl vanillin, benzyl alcohol, and furaneol. Cytotoxicity was determined with the MTT and LDH assays, and inflammatory markers were quantified with ELISAs. Churrios was cytotoxic to keratinocytes in the MTT assay, and both fluids induced ROS production in the medium (ROS-Glo™) and …

Mechanistic Investigation Of Neuropeptide S-Nitrosylation By Nitric Oxide Moieties: A Kinetic And Thermodynamic Approach, Vusumuzi Leroy Sibanda

Dissertations and Theses

This dissertation focuses on providing quantitative insights regarding kinetic, thermodynamic and mechanistic parameters of neuropeptide S-nitrosylation by nitrous acid (HNO₂), peroxynitrite (ONOO^-) and S-nitroso-N-acetyl-D,L-penicillamine (SNAP) to produce S-nitrosothiols (SNOs). Peptide thiol stability and the formation of SNOs from neuropeptides; arginine vasopressin (AVP), somatostatin-14 (SST-14) and urotensin II (U-II) was studied. Investigations into the effects of temperature, copper chelators and pH on peptide thiol autoxidation show that AVP, SST-14 and U-II thiols have half-lives of 30, 44 and 28.2 mins respectively at physiologically relevant temperature and pH in the absence of metal chelators. Target peptide thiols were …

Automated Statistical Structural Testing Techniques And Applications, Yang Shi

Dissertations and Theses

Statistical structural testing(SST) is an effective testing technique that produces random test inputs from probability distributions. SST shows superiority in fault-revealing power over random testing and deterministic approaches since it heritages the merits from both of them. SST ensures testing thoroughness by setting up a probability lower-bound criterion for each structural cover element and test inputs that exercise a structural cover element sampled from the probability distribution, ensuring testing randomness. Despite the advantages, SST is not a widely used approach in practice. There are two major limitations. First, to construct probability distributions, a tester must understand the underlying software's structure, …

A Paleoseismic Study Of The Twin Lakes Fault, Mount Hood Fault Zone, Oregon, Charlie Carr, Ashley R. Streig

McNair Symposium

Recent geologic mapping on high-resolution topography from lidar has led to the discovery of a zone of active faults on Mount Hood. The Mt. Hood Fault Zone consists of four separate faults, and stretches ~55 km from south to north, and crosses the summit of Mount Hood. The focus of this study is the northern section of Twin Lakes Fault, which lies directly south of Mount Hood and adjacent to OR35 and the White River. Lidar topography reveals the west side down normal displacement on the Twin Lakes fault. The highest tectonic seismicity rates in the Mount Hood area occur …

Ronald E. Mcnair Scholars Program Profiles And Abstracts 2021, Mcnair Scholars Program

McNair Symposium

This is the complete event program and provides presentation abstracts and biographies of McNair scholars and their mentors.

Quantum Grover's Oracles With Symmetry Boolean Functions, Peng Gao

Dissertations and Theses

Quantum computing has become an important research field of computer science and engineering. Among many quantum algorithms, Grover's algorithm is one of the most famous ones. Designing an effective quantum oracle poses a challenging conundrum in circuit and system-level design for practical application realization of Grover's algorithm.

In this dissertation, we present a new method to build quantum oracles for Grover's algorithm to solve graph theory problems. We explore generalized Boolean symmetric functions with lattice diagrams to develop a low quantum cost and area efficient quantum oracle. We study two graph theory problems: cycle detection of undirected graphs and generalized …

Proximal Policy Optimization For Radiation Source Search, Philippe Erol Proctor

Dissertations and Theses

Rapid localization and search for lost nuclear sources in a given area of interest is an important task for the safety of society and the reduction of human harm. Detection, localization and identification are based upon the measured gamma radiation spectrum from a radiation detector. The nonlinear relationship of electromagnetic wave propagation paired with the probabilistic nature of gamma ray emission and background radiation from the environment leads to ambiguity in the estimation of a source's location. In the case of a single mobile detector, there are numerous challenges to overcome such as weak source activity, multiple sources, or the …

Information Security Maturity Model For Healthcare Organizations In The United States, Bridget Joan Barnes Page

Dissertations and Theses

This research provides a maturity model for information security for healthcare organizations in the United States. Healthcare organizations are faced with increasing threats to the security of their information systems. The maturity model identifies specific performance metrics, with relative importance measures, that can be used to enhance information security at healthcare organizations allowing them to focus scarce resources on mitigating the most important information security threat vectors. This generalizable, hierarchical decision model uses both qualitative and quantitative metrics based on objective goals. This model may be used as a baseline by which to measure individual organizational performance, to measure performance …

Microscopic Object Classification Through Passive Motion Observations With Holographic Microscopy, Christian Lindensmith, Jay Nadeau, Manuel Bedrossian, Louis Sumrall, J. Kent Wallace, Eugene Serabyn

Physics Faculty Publications and Presentations

Digital holographic microscopy provides the ability to observe throughout a volume that is large compared to its resolution element without the need to refocus through the volume. This capability enables simultaneous observations of large numbers of small objects within such a volume. We have constructed a microscope that can observe a volume 0.4 x 0.4 x 1.0 μm with submicrometer resolution for observation of microorganisms and minerals in liquid environments in earth and on potential planetary missions. Because environmental samples are likely to contain mixtures of inorganics and microorganisms that are of comparable sizes near the resolution limit of the …

Participatory Gis Mapping Highlights Indirect Use And Existence Values Of Coastal Resources And Marine Conservation Areas, Kaegan M. Scully‐Engelmeyer, Elise F. Granek, Max Nielsen-Pincus, Greg Brown

Environmental Science and Management Faculty Publications and Presentations

Consideration of social and cultural dimensions in coastal and marine planning has increased and ecosystem services provide important framing to investigate values and priorities associated with these systems. Research efforts in coastal communities offer insights on social dimensions of ocean and coastal management decisions, but questions remain about how demographics and geographic residence affect perceptions of marine resources and management. We conducted and analyzed a public participation geographic information system (PPGIS) mapping survey of Oregon residents to capture uses and perceived values of coastal and marine areas. We measured coastal values, explored regional differences in those values, and identified a …

Linear Nearest Neighbor Flocks With All Distinct Agents, R. G. Lyons, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

This paper analyzes the global dynamics of one-dimensional agent arrays with nearest neighbor linear couplings. The equations of motion are second-order linear ODE’s with constant coefficients. The novel part of this research is that the couplings are different for each distinct agent. We allow the forces to depend on the positions and velocity (damping terms) but the magnitudes of both the position and velocity couplings are different for each agent. We, also, do not assume that the forces are “Newtonian” (i.e. the force due to A on B equals the minus the force of B on A) as this assumption …

Marine Debris And Human Health: An Exposure Pathway Of Pops?, Katie Conlon

Urban Studies and Planning Faculty Publications and Presentations

Although there are not any direct studies linking persistent organic pollutants (POPs) accumulated on marine debris to human health, there are numerous studies showing human health impacts from repeated and high level POP exposure, as well as studies that show POPs accumulate on plastic debris in the marine environment. With this knowledge, there is a need for greater awareness of the risks of POP exposure for those who handle marine debris regularly, especially in contexts of higher exposure such as those working in marine debris concentrated areas. Amongst the scientific community, understanding of the exposure risk might be high, but …

Insight Into The Early Exhumation Of The Cycladic Blueschist Unit, Syros, Greece: Combined Application Of Zoned Garnet Geochronology, Thermodynamic Modeling, And Quartz Elastic Barometry, Jennifer S. Gorce, Mark J. Caddick, Ethan F. Baxter, Besim Dragovic, John C. Schumacher, Robert J. Bodnar, Jamie F. Kendall

Geology Faculty Publications and Presentations

Constraining conditions and mechanisms of the early stages of exhumation from within subduction zones is challenging. Although pressure, temperature, and age can be inferred from the exhumed rock record, it is generally difficult to derive each of these parameters from any single rock, thus demanding assumptions that diverse data from multiple samples can be safely combined into a single pressure-temperature-time (P-T-t) path that might then be used to infer tectonic context and mechanisms of exhumation. Here, we present new thermobarometric and geochronologic information preserved in a single sample from Syros, Greece, to deduce the …

Graphical Models In Reconstructability Analysis And Bayesian Networks, Marcus Harris, Martin Zwick

Systems Science Faculty Publications and Presentations

Reconstructability Analysis (RA) and Bayesian Networks (BN) are both probabilistic graphical modeling methodologies used in machine learning and artificial intelligence. There are RA models that are statistically equivalent to BN models and there are also models unique to RA and models unique to BN. The primary goal of this paper is to unify these two methodologies via a lattice of structures that offers an expanded set of models to represent complex systems more accurately or more simply. The conceptualization of this lattice also offers a framework for additional innovations beyond what is presented here. Specifically, this paper integrates RA and …

Exploring Linkages Between Landscape Patterns And Freshwater And Estuarine Bivalves In The Coast Range Of Oregon, Kaegan Michael Scully-Engelmeyer

Dissertations and Theses

Spatial configurations of landscape variables (biotic, abiotic, and socio-ecological) affect and are affected by ecological processes and species in watersheds. This dissertation explores relationships among landscape patterns, ecosystem processes and bivalve species dynamics in coastal watersheds in Oregon, USA. I approached this broad topic through two primary avenues of research: investigating cross-ecosystem threats from pesticide use in forestland management to downstream aquatic environments, and the landscape ecology of an at-risk freshwater mussel species.

Terrestrial land use activities present cross-ecosystem threats to riverine and marine species and processes. Specifically, pesticide runoff can disrupt hormonal, reproductive, and developmental processes in aquatic organisms, …