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Portland State University

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Examining The Interaction Between Calcium Supplement Use, Demographics, And Lifestyle Factors On Bone Health Of Women, Vix J. Talbot Jun 2024

Examining The Interaction Between Calcium Supplement Use, Demographics, And Lifestyle Factors On Bone Health Of Women, Vix J. Talbot

University Honors Theses

Osteoporosis is a condition which poses a significant health threat, particularly among women during the menopause transition, where accelerated bone loss increases fracture risk. Calcium supplementation has been shown to be an important intervention to mitigate bone mineral density (BMD) decline during this and other periods of life. However, the efficacy of calcium supplementation is influenced by various individual factors, including demographics and lifestyle habits. This study investigates the interaction between calcium supplement use, and several interaction terms on bone health in women. Multiple linear regression analysis is employed to assess the impact of these factors on BMD. Data from …


Henna Chatbot Capstone Review, Kobe Norcross Jun 2024

Henna Chatbot Capstone Review, Kobe Norcross

University Honors Theses

This thesis reviews the development of the Henna Chatbot, an AI-powered DEI consultant designed to provide personalized feedback to organizations. Sponsored by DEI consultant Arsh Haque, the project aims to address gaps in current DEI software, which often lacks team-specific feedback. The Henna Chatbot leverages GPT-3.5 Turbo to create an affordable SaaS platform where organizations can train Henna with their DEI values, and Henna will help organizations stay aligned with those values. The project spanned twenty weeks and was completed by a team of eight computer science students at Portland State University. The development process followed Agile methodologies, emphasizing effective …


Microplastic Pollution In Stormwater: Preliminary Findings From The Oregon Coast, Jazmine R. Compton Jun 2024

Microplastic Pollution In Stormwater: Preliminary Findings From The Oregon Coast, Jazmine R. Compton

University Honors Theses

Microplastics have become ubiquitous in marine environments and pose a risk to ecosystem, organismal, and human health. Stormwater runoff has been suggested to be a major contributor to marine microplastic pollution. This project aims to quantify the average concentration of microplastics in stormwater in a community on the Oregon Coast. To accomplish this, stormwater samples were collected from five sites in Cannon Beach, Oregon, and one sample was analyzed using a dissection microscope. Using this technique, the number, size, and composition of the microplastic particles were determined. The calculated concentration of microplastics in the stormwater sample was 12.21 MPs/L, and …


Student Perceptions: How Stem Students Value Belonging Interventions, Elizabeth A. Runkel Baez Jun 2024

Student Perceptions: How Stem Students Value Belonging Interventions, Elizabeth A. Runkel Baez

University Honors Theses

With the prioritization of increasing Science, Technology, Engineering, and Mathematics (STEM) graduates in the United States, researchers have become increasingly interested in how to promote STEM students’ sense of belonging. Sense of belonging is considered a marker of persistence in STEM. Facilitated ‘belonging interventions’ are one way to strengthen a sense of belonging amongst STEM students. How students respond to, value, and understand these belonging interventions is relatively understudied. In this study, focus groups were conducted with STEM students from a single university to investigate how they value an in-class belonging activity. Qualitative thematic coding of focus group responses revealed …


Piloting A Drain Gauge As A Method Of Measuring Runoff From Ecoroofs In Portland, Trinity Perrin Jun 2024

Piloting A Drain Gauge As A Method Of Measuring Runoff From Ecoroofs In Portland, Trinity Perrin

University Honors Theses

The following paper will be exploring a pilot methodology of a drain gauge system I built that’s used to calculate stormwater runoff from ecoroofs in Portland, Oregon. The drain gauge is a less studied technique for measuring ecoroof runoff, but holds high potential for developing better monitoring and management of ecoroofs within the city of Portland. What separates this stormwater runoff capturing device apart from other stormwater runoff calculation techniques is its adaptable design and simple installation. The drain weir can be placed in any roof drain that an ecoroof has been installed simply by placing it into a roof …


The Institutional Challenges Of A Quantified Self Study An Attempt To Ascertain How Data Collected From A Mobile Device Can Be An Indicator Of Personal Mental Health Over Time., Julian E. Lazaras Jun 2024

The Institutional Challenges Of A Quantified Self Study An Attempt To Ascertain How Data Collected From A Mobile Device Can Be An Indicator Of Personal Mental Health Over Time., Julian E. Lazaras

University Honors Theses

The adoption of an application of new technology always comes with a bias, this is never more true for the case of human behavioral analytics within higher education. While movements such as the quantified self movement make strides to reinterpret the realm of data analytics, psychology, and computer science, there are inevitably limitations to the adoption and application of such approaches within the standard realm of research. Herein is presented a case where an effort to evaluate the prospect of use of mobile phone data as secondary indicators of personal mental health through the lens of data analysis was put …


Cards With Class: Formalizing A Simplified Collectible Card Game, Dan Ha Jun 2024

Cards With Class: Formalizing A Simplified Collectible Card Game, Dan Ha

University Honors Theses

Collectible card games (CCGs) have been a wildly popular game genre since the release of Wizards of the Coast’s Magic: The Gathering. These games revolve around their thousands of cards and the hundreds of thousands of interactions they can create with their many effects. For designers, it is an incredibly demanding task to ensure that every single card works properly and that each card’s text unambiguously conveys its intended behavior in all cases. The task only grows more difficult over time as the number of cards in the game grows and card effects become more complex or experimental. If the …


Development Of A Two-Photon Imaging System, Jesseca Hollenbaugh Jun 2024

Development Of A Two-Photon Imaging System, Jesseca Hollenbaugh

University Honors Theses

The objective of this project was to convert a Sarastro 2000 confocal laser scanning microscope (CLSM) into a system capable of far-field two-photon excitation (TPE) imaging for the use of the PSU Biology department. TPE microscopy operates on the ability of fluorophores to accept two photons each with half the energy of a desired transition in a single quantum event via a virtual energy state and then emit a higher energy photon upon relaxation. This is preferable to single-photon excitation (SPE) imaging due to lower photon imaging, causing less damage to delicate biological samples, as well as the inherent localization …


Auditory Ace Mobile Application Capstone Review, Makayla Smith Jun 2024

Auditory Ace Mobile Application Capstone Review, Makayla Smith

University Honors Theses

This paper describes the development process and outcomes of my 2023-2024 Capstone Project, Auditory Ace, a self-directed auditory training mobile application for individuals with cochlear implants. Recognizing the limitations of current market offerings, Dr. Timothy Anderson created a Capstone project proposal to develop an accessible auditory training mobile application. The Capstone team that took on this proposal consisted of Darya Haines, Dustin Huynh, Jordan Nguyen, Nihar Koppolu, Scott Thorkelson, Sienna Day, and myself, Layla Smith. This paper is structured to follow the Agile software development methodology, which we used to develop Auditory Ace, reviewing in detail every major choice we …


The Cascading Effects Of Database Design, Liam C. Mccracken Jun 2024

The Cascading Effects Of Database Design, Liam C. Mccracken

University Honors Theses

This paper details how a relational database influenced the design of the rest of a software project. The software project in question is WonderTix, an open-source ticketing and donation platform for the use of Portland Playhouse under continuous development by teams of Portland State students as their computer science capstone project. The paper, a capstone review thesis, examines WonderTix as an instantiation of the Model-View-Controller design pattern, noting how the model, a relational database based on the SQL standard, influenced the design of the view and controller components. This influence is explored from three angles. First, when the implementation of …


Lang2views Capstone: The Importance Of A Conscientious Team Lead, Joseph D. Wornath Jun 2024

Lang2views Capstone: The Importance Of A Conscientious Team Lead, Joseph D. Wornath

University Honors Theses

This review essay reflects the Lang2views capstone project from the perspective of a team lead. The Lang2views capstone project was a web-based user interface designed to simplify how the Lang2views corporation localizes videos into other languages for their clients. Our capstone group was split into three subgroups: front-end, back-end, and DevOps. The strategy for completing the project went through a major change midway through development wherein we changed our software development methodology from a more rigid Waterfall-type approach to a more flexible Agile methodology. Because of this, many of the initially planned features had to be reevaluated as out of …


Remediating History – A Review Of Restoration For Creeks Polluted From Historical Mining Sites, With The Red Boy Mine As A Primary Case Study, Kara Atiyeh Jun 2024

Remediating History – A Review Of Restoration For Creeks Polluted From Historical Mining Sites, With The Red Boy Mine As A Primary Case Study, Kara Atiyeh

University Honors Theses

I conducted a literature review to examine the key aspects of restoring watersheds affected by pollution from historical mining. This review is then applied to a case study discussion of the Red Boy Mine and Clear Creek remediation project in Granite, Oregon. The goal of this discussion is to explore how an analysis of site conditions along with current literature on management practices can help guide these projects. Thousands of abandoned hard rock mines remain throughout the country, and many pose serious environmental health effects. Heavy metals like cadmium, nickel, and copper are brought to the surface from mining activity, …


Virtual Field Environments Capstone Software Review, Ashton Sawyer Jun 2024

Virtual Field Environments Capstone Software Review, Ashton Sawyer

University Honors Theses

This is a review of the Virtual Field Environments computer science capstone project, sponsored by geology professor Rick Hugo. The tool aims to create and render VFEs, interactable 360° environments hosted on the web that are used as virtual field trips for K-12 students. This essay discusses the development process, including understanding requirements, tool and technology selection, problem-solving, and decision-making strategies. It also highlights the differences between the capstone and the other core computer science courses, and how those differences help to prepare students for the workforce. The project was completed over the course of twenty weeks by a team …


The Lewis Acidity Of Imidazole-Derived Diaryliodonium Zwitterions, Cyrus Rose May 2024

The Lewis Acidity Of Imidazole-Derived Diaryliodonium Zwitterions, Cyrus Rose

University Honors Theses

Diaryliodonium salts can be used as effective aryl-transfer agents in reactions to form novel molecules with diverse applications including pharmaceuticals and agrochemicals without using harsh reaction conditions and transition metal reagents. In recent years, interest in the applications of the Lewis acidity of iodonium ion catalysts has increased. Despite this, the quantification of the Lewis acidities of diaryliodonium salts are scarce. Even rarer, there has not been much study into the Lewis acidities of zwitterionic diaryliodonium salts. For zwitterions, there is no counter anion that would come into consideration in regard to its Lewis acidity. To expand the understanding of …


Extended Producer Responsibility: Successes, Failures, And The Future Of Oregon Recycling, Zoe Vandal May 2024

Extended Producer Responsibility: Successes, Failures, And The Future Of Oregon Recycling, Zoe Vandal

University Honors Theses

Extended Producer Responsibility (EPR) is a waste management program used globally to improve the recovery, recycling, and management of solid waste materials. There are three types of EPR programs defined by their target materials: electronic and electrical waste (WEEE) EPR, hazardous waste EPR, and packaging EPR. Europe has implemented all three types with relative success. The US has implemented WEEE EPR and hazardous waste EPR and is currently in the process of implementing packaging EPR on a state scale in Oregon, California, Colorado, Maine, and Maryland with 10 more bills being introduced in 2024 alone. Oregon’s EPR program will be …


Spectroscopic End Point Detection With An Electron Beam Evaporator, Ryan Mcgraw Mar 2024

Spectroscopic End Point Detection With An Electron Beam Evaporator, Ryan Mcgraw

University Honors Theses

Spectroscopic end point detection is a common tool used for measuring slope changes in wavelength intensity. Using algorithms able to apply this concept, coatings will be able to be dynamically measured in real time and stopped at the appropriate level to ensure process uniformity. It is currently applied to reductive processes such as etching, where the surface will start to be eaten away, creating a plasma. When the entire amount of a material on a substrate has been eaten away, the plasma will change color as it is beginning to etch a different material. Using a spectrometer, this point where …


Birkhoff Summation Of Irrational Rotations: A Surprising Result For The Golden Mean, Heather Moore Mar 2024

Birkhoff Summation Of Irrational Rotations: A Surprising Result For The Golden Mean, Heather Moore

University Honors Theses

This thesis presents a surprising result that the difference in a certain sums of constant rotations by the golden mean approaches exactly 1/5. Specifically, we focus on the Birkhoff sums of these rotations, with the number of terms equal to squared Fibonacci numbers. The proof relies on the properties of continued fraction approximants, Vajda's identity and the explicit formula for the Fibonacci numbers.


Understanding Waveguides In Resonance, Pieter Johannes Daniel Vandenberge Mar 2024

Understanding Waveguides In Resonance, Pieter Johannes Daniel Vandenberge

Dissertations and Theses

Several important classes of modern optical waveguides, including anti-resonant reflecting and photonic bandgap fibers, make use of geometries that guide energy in low refractive index material, a property that makes them of significant interest in numerous applications, notably including high-power delivery and guidance. These waveguides frequently exhibit resonance phenomena, in which their ability to propagate an input signal is sharply curtailed at particular operating frequencies. In this work we detail new advances in understanding these resonance effects and their implications for numerical modeling of these structures.

Part 1 focuses on the fields of slab waveguides, relatively simple structures for which …


Supply Is Not Limulus: Research Review Of Horseshoe Crab Conservation In The Face Of Intense Pharmaceutical Demand, Zoya Galeev Mar 2024

Supply Is Not Limulus: Research Review Of Horseshoe Crab Conservation In The Face Of Intense Pharmaceutical Demand, Zoya Galeev

University Honors Theses

Horseshoe crabs are being used by the pharmaceutical industry to conduct endotoxin tests using LAL derived from the organism’s blood to ensure safe medical practice. Their annual collection and bleeding, while not always leading to mortality, affects horseshoe crab behavior and health. This research seeks to understand how the American horseshoe crab, L. polyphemus, is being used by pharmaceutical agencies and the implications that their harvesting has on the industry and the conservation of the species. Studies were collected from the past decade across two databases, Web of Science (WOS) and PubMed, to assess present conservation techniques to reduce …


Mmwave Rat Optimization: Mac Layer Initial Access Design And Transport Layer Integration, Suresh Srinivasan Feb 2024

Mmwave Rat Optimization: Mac Layer Initial Access Design And Transport Layer Integration, Suresh Srinivasan

Dissertations and Theses

MmWave Radio Access Technology (RAT) is a promising technology for wireless communication due its large bandwidth and is already being deployed in 5G cellular and emerging WiFi technologies. MmWave systems use highly directional beams with narrow beamwidths to overcome the high path loss associated with their frequency bands. A mmWave radio can be used either in a standalone mode (where all radios use the same technology) or simultaneously with other technologies such as LTE and low frequency WiFi in a communication mode commonly referred to as integrated mode. This thesis proposes two methods to optimize mmWave RAT performance in both …


How Are Oregon's Rural Indigenous Communities Overcoming Water Access Issues?, Tyren John Thompson Dec 2023

How Are Oregon's Rural Indigenous Communities Overcoming Water Access Issues?, Tyren John Thompson

Dissertations and Theses

This study investigates how water insecurity affects Indigenous communities in Grand Ronde, Warm Springs, and Umatilla, Oregon, through loss of clean drinking water, access to culturally significant foods, and exposure to pollution. Each community offers innovative solutions drawing on their Indigenous knowledge to overcome water supply challenges. Communities with more resources are better equipped to cope with water insecurity and environmental degradation.


Tiny Drifters Amidst Global Change: Examining Environmental Drivers, Trophic Impacts, And Management Strategies Of Estuarine Plankton Communities In The Anthropocene, Taylor Nicole Dodrill Dec 2023

Tiny Drifters Amidst Global Change: Examining Environmental Drivers, Trophic Impacts, And Management Strategies Of Estuarine Plankton Communities In The Anthropocene, Taylor Nicole Dodrill

Dissertations and Theses

Plankton productivity supports estuarine food webs, and has been tied to the success of fisheries, macroinvertebrates, and cultured shellfish yields. Climate change and alterations to nutrient loads are thought to be influencing plankton assemblages, with toxin-producing harmful algal blooms (HABs) on the rise and nutritional quality of plankton declining globally. These shifts in plankton communities may contribute to low biomass yields and toxin-based closures of important fisheries. The objectives of this dissertation are to identify environmental drivers, trophic impacts, and management strategies to understand and respond to changing estuarine plankton communities. To address these objectives, I used a combination of …


The Discovery Of Diverse Picophytoplankton Populations In The Columbia And Willamette Rivers Using Flow Cytometry, Kylee Brevick Dec 2023

The Discovery Of Diverse Picophytoplankton Populations In The Columbia And Willamette Rivers Using Flow Cytometry, Kylee Brevick

Chemistry Undergraduate Departmental Honors Theses

As important primary producers, picophytoplankton determine the flow of carbon and energy in aquatic ecosystems. Picocyanobacteria are one picophytoplankton group known to be dominant in oceans and lakes, but they are still poorly understood in river systems. This project examined picophytoplankton communities in two distinct river systems: the Columbia and Willamette Rivers in Portland, Oregon. I aimed to characterize and quantify the picophytoplankton populations in the context of the environmental conditions of the two rivers. I used flow cytometry to detect cells based on their relative size and pigment fluorescence. I sampled nearly weekly for ten months to capture population …


The Effects Of Salt Marsh Restoration On The Hydrology Of Salt Marsh Channels, Isis Kontas Dec 2023

The Effects Of Salt Marsh Restoration On The Hydrology Of Salt Marsh Channels, Isis Kontas

University Honors Theses

Salt marshes produce many ecosystem services, from water purification to protection from hurricanes. Despite their benefits, salt marshes have been impacted negatively by human activities. There are many salt marsh restoration projects that intend to bring back all ecological functions and services. Quantifiable measurements are needed to evaluate the effectiveness of such restoration efforts. Earlier work by Reagan Thomas demonstrated what happens to the hydrology of salt marsh channels when they are adjacent to restored salt marshes. This study builds on Thomas’ work and uses the sinuosity of channels as a quantitative, representative metric of salt marsh hydrology restoration effectiveness. …


How Beavers (Castor Canadensis) Affect Habitat Availability For Two Native Oregon Turtles: Actinemys Marmorata And Chrysemys Picta Bellii, Rodé Krige Dec 2023

How Beavers (Castor Canadensis) Affect Habitat Availability For Two Native Oregon Turtles: Actinemys Marmorata And Chrysemys Picta Bellii, Rodé Krige

University Honors Theses

Oregon is home to two native freshwater turtle species: the northwestern pond turtle and the western painted turtle. Both turtles are Oregon conservation strategy species with a status rating of sensitive, indicating declining populations. Oregon’s decline in these turtle’s populations is thought to be predominantly due to loss and degradation of habitat that results from development and urbanization. Beavers’ ability to dam streams and create ponds may be creating habitat usable by turtles, but the relationship is under-studied. This study assessed water temperature, basking habitat, and overall turtle habitat suitability at beaver-dammed and control ponds in Portland, Oregon. Average basking …


Energy Auction With Non-Relational Persistence, Michael Ramez Howard Nov 2023

Energy Auction With Non-Relational Persistence, Michael Ramez Howard

Dissertations and Theses

As the current landscape for electric vehicles changes, options for remote charging are expanding to keep up. In the United States alone, sales of electric vehicles grew 85% from 2020 until hitting 450,000 units by the end of 2021. While these growing sales are encouraging, commercial charging stations have a long way to go before they are as ubiquitous as gasoline stations are today. The peer-to-peer energy auction helps fill the gap in underserved areas by allowing private homeowners to share their charging facilities with other electric vehicle drivers. The auction framework wraps existing charging outlets with a Cloud-connected microcontroller. …


Tidal Bed Stress Asymmetry And Sediment Transport In Estuaries, Austin Scott Hudson Nov 2023

Tidal Bed Stress Asymmetry And Sediment Transport In Estuaries, Austin Scott Hudson

Dissertations and Theses

Rivers and estuaries provide numerous ecological, economic, and cultural resources. The value of these resources is greatly influenced by sediment transport processes, which can be affected by human activities and climate variability. A key driver of sediment transport in tidal rivers and estuaries is tidal asymmetry of velocity and bed stress, which can manifest from both non-linear tidal interactions and linear interactions among astronomical tidal constituents.

In this study, an analytical framework is developed to examine and describe the dynamics of bed stress asymmetry in semidiurnal, diurnal, and mixed-tide estuaries (Chapter 1). While tidal velocity asymmetry has been previously analyzed, …


Forest Generating Functions Of Directed Graphs, Ewan Joaquin Kummel Nov 2023

Forest Generating Functions Of Directed Graphs, Ewan Joaquin Kummel

Dissertations and Theses

A spanning forest polynomial is a multivariate generating function whose variables are indexed over both the vertex and edge sets of a given directed graph. In this thesis, we establish a general framework to study spanning forest polynomials, associating them with a generalized Laplacian matrix and studying its properties. We introduce a novel proof of the famous matrix-tree theorem and show how this extends to a parametric generalization of the all-minors matrix-forest theorem. As an application, we derive explicit formulas for the recently introduced class of directed threshold graphs.

We prove that multivariate forest polynomials are, in general, irreducible and …


Cognitive Engagement During Group Learning Activities In Chemistry Courses: An Analysis Of Student Discourse, Safaa Youssef El-Mansy Nov 2023

Cognitive Engagement During Group Learning Activities In Chemistry Courses: An Analysis Of Student Discourse, Safaa Youssef El-Mansy

Dissertations and Theses

As educators, our goal is to help our students be successful, but in order to accomplish this, we need to understand what factors contribute to student success. One factor, small-group active learning, has been correlated to improved academic outcomes; however, the magnitude of this improvement can vary across different courses, different types of group work, and even across courses that use the same group work structure. Therefore, it is important to understand what aspects of group work contribute to its effectiveness. The work presented in this dissertation investigated one specific aspect: students’ cognitive engagement. This was done by analyzing the …


Using Biometrics, Behavioral Observations, And Multiple Molecular Techniques To Assess The Impacts Of Changes In Temperature And Salinity On The Common Bay Mussel (Mytilus Trossulus), Casey Martin Nov 2023

Using Biometrics, Behavioral Observations, And Multiple Molecular Techniques To Assess The Impacts Of Changes In Temperature And Salinity On The Common Bay Mussel (Mytilus Trossulus), Casey Martin

Dissertations and Theses

The intertidal zone is a place of rapid and frequent change that is home to a variety of creatures who are essential to the integrity of the habitat. Mussels are robust sessile bivalves that anchor to the rocks of the intertidal. The prominent species on the Oregon Coast, the Common Bay Mussel (Mytilus trossulus), plays an essential role as a coastal food source, water column filter, and barrier to prevent erosion due to wave action. Mytilus trossulus withstands daily shifts in temperature, salinity, and tide, as well as seasonal changes. Global climate change due to excess carbon emissions …