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From Novice To Expert: Exploring The Relationship Between Information Literacy Threshold Concepts And Epistemological Development, Amanda L. Folk Jun 2025

From Novice To Expert: Exploring The Relationship Between Information Literacy Threshold Concepts And Epistemological Development, Amanda L. Folk

Communications in Information Literacy

The Framework for Information Literacy for Higher Education articulates the ways of thinking, knowing, and doing that are valued in the academic community. Prior to the Framework, several scholars explored the potential relationship between information literacy and epistemological development, or the ways in which learners develop their understanding of and positionality to knowledge creation. However, the intersections of information literacy and epistemological development have been underexamined in the era of the Framework. In this article, I analyze the Framework through the lens of two epistemological development models, the Epistemological Reflection Model (Baxter-Magolda, 1992) and Reflective Judgement Model (King …


Poa Annua Ecology, Biology, And Integrated Weed Management Practices In Turfgrass, David Ervin Jun 2025

Poa Annua Ecology, Biology, And Integrated Weed Management Practices In Turfgrass, David Ervin

Environmental Science and Management Faculty Publications and Presentations

Poa annua L. is one of the most widespread and troublesome weeds of turfgrass. It persists as both an annual and perennial and is adaptable to almost any static maintenance regime, including adaptation to mowing heights and evolution of herbicide resistance. This management guide is intended to provide stakeholders with a summary of new and existing knowledge on integrated Poa annua management. Here we review the basic biology and ecology, as well as practical integrated weed management (IWM) strategies developed for its control.


Indigenous Science And The Legacy Of Fire: Resilience, Fuels, Mosaics, And Eco-Cultural Landscapes In Oregon’S Coastal And Cascade Range, Julia Alcalá Jun 2025

Indigenous Science And The Legacy Of Fire: Resilience, Fuels, Mosaics, And Eco-Cultural Landscapes In Oregon’S Coastal And Cascade Range, Julia Alcalá

University Honors Theses

Most of Oregon's western Cascade and Coastal range is a landscape that has historically been considered devoid of mid to low-intensity fires by Western science. However, for time immemorial, Indigenous peoples have been stewarding the forests through the use of "good fire," creating diverse and heterogenous landscapes with mixed fire regimes, ranging from less than a decade to several centuries since the last fire, resulting in a mosaic of patchy forest, oak savannas, prairies, and wetlands. Yet centuries of Indigenous displacement, cultural assimilation, and suppression of cultural burning contributed to this prevailing belief. Despite that, in recent decades, Western scientists …


Surface Temperature Analysis Report: Kellogg Creek Restoration & Community Enhancement Project, Dalton Palin Jun 2025

Surface Temperature Analysis Report: Kellogg Creek Restoration & Community Enhancement Project, Dalton Palin

University Honors Theses

Kellogg Creek is located in the Kellogg-Mt Scott watershed which flows through downtown Milwaukie, Oregon into the Willamette River. At the confluence of Kellogg Creek and the Willamette River is the Kellogg Dam. This dam impedes salmon, steelhead, and lamprey movement up Kellogg Creek, which is known historically as a salmon and steelhead rearing and migrating habitat. A plan to remove Kellogg Dam and restore 14 acres of Kellogg Creek is in progress by North Clackamas Watersheds Council (NCWC) and partners. Water temperature studies in Kellogg Creek have been conducted for the past several years, this report analyzed thermal surface …


An Exposition Of "Probabilistic Polynomials And Hamming Nearest Neighbors", Vivek Srirama Jun 2025

An Exposition Of "Probabilistic Polynomials And Hamming Nearest Neighbors", Vivek Srirama

University Honors Theses

This paper is an exposition of the paper Probabilistic Polynomials and Hamming Nearest Neighbors by Josh Alman and Ryan Williams. It presents the findings of this paper in a more accessible format for Computer Science students earlier in their career who may not be as familiar with Computational Theory and its concepts as their PhD counterparts are. The paper assumes that the reader has a basic understanding of Algorithms and Complexity, typically obtained in an introductory level Algorithms course.

The paper by Alman and Williams analyzes a specific problem known as the Hamming Nearest Neighbor problem. All known solutions for …


Rebuilding Consent: Fear, Trust, And The Future Of Nuclear Energy, Austin Dunham Jun 2025

Rebuilding Consent: Fear, Trust, And The Future Of Nuclear Energy, Austin Dunham

University Honors Theses

This thesis traces the cultural and emotional roots of nuclear fear in the United States and explores how those inherited anxieties continue to shape public resistance to nuclear energy in the face of a worsening climate crisis. Drawing on personal narrative, risk perception theory, and the history of nuclear discourse - from Hiroshima to Chernobyl to today - the research examines how trust, rather than technology, remains the largest barrier to progress. By analyzing the stories we tell about energy, disaster, control, and overall perceived risk, this work asks what it would take for Americans to imagine nuclear energy not …


Raising The Roof For All: Integrating Companion Planting Ecology, Policy And Community In Portland's Green Roof Future, Zoe Edelman Jun 2025

Raising The Roof For All: Integrating Companion Planting Ecology, Policy And Community In Portland's Green Roof Future, Zoe Edelman

University Honors Theses

Green roofs, or ecoroofs, provide environmental and social benefits in urban areas. Ecoroofs manage stormwater by absorbing rainfall, reducing rooftop temperatures, supporting pollinators, and offering green space in densely developed cities. Portland, Oregon has adopted progressive policies that encourage green roof installation through incentives and building requirements. However, many ecoroofs in the city are underperforming due to poor maintenance, low public awareness, and limited access to rooftop spaces. This thesis explores whether companion planting can improve the ecological performance and long- term viability of extensive green roofs. A rooftop experiment at Portland State University tested the growth of radishes, with …


Early-Stage Detection Of Copper Ion Release From Bronze Corrosion Using Uv/Vis Spectroscopy And Hydrogel Sensing, Hibah Khan Jun 2025

Early-Stage Detection Of Copper Ion Release From Bronze Corrosion Using Uv/Vis Spectroscopy And Hydrogel Sensing, Hibah Khan

University Honors Theses

Detecting copper(I) (Cu⁺) release at early corrosion stages is important for preserving bronze heritage materials. This study investigated the use of neocuproine (NC), a Cu⁺-specific ligand, for simple and selective colorimetric detection of Cu⁺ in solution. NC reacts with Cu⁺ to form a Cu(NC)₂ complex, which produces a distinct orange-red color with peak absorbance at 455 nm. Solutions were prepared with varying concentrations of Cu⁺ generated by reducing Cu²⁺ with excess ascorbic acid. Ultraviolet/Visible (UV/Vis) spectroscopy was used to quantify absorbance changes. The absorbance at 455 nm increased linearly across the tested Cu⁺ concentration range (6.25–200 µM) with an R² …


Influencing Factors Of Angle-Of-Arrival Estimator Based On Deep Learning, Guohao Pang May 2025

Influencing Factors Of Angle-Of-Arrival Estimator Based On Deep Learning, Guohao Pang

Dissertations and Theses

Deep learning (DL)-based angle-of-arrival (AoA) estimation offers significant advantages over traditional signal processing methods, especially in complex and high-noise environments. However, situational complexity and differences in hardware can significantly impact the estimator's performance. It is therefore of interest to investigate the relationship between the performance of deep learning models and the variation of physical parameters such as the number of signal sources, the number of receiving antennas, and the signal-to-noise ratio (SNR). In this study, we investigate the impact of these variations on deep learning-based AoA estimation by systematically analyzing how the variations in the characteristics of the received signal …


Their Will Is Wealth: American Billionaires, Illiberal Capital, And Their Immunity To Federal Law, Conor Kawika Carroll May 2025

Their Will Is Wealth: American Billionaires, Illiberal Capital, And Their Immunity To Federal Law, Conor Kawika Carroll

Dissertations and Theses

Billionaires are inherently unique political actors. They, and their wealth, are a species apart. This rarity is measurable by quantifying relative consequences for actions made on behalf of that wealth. This thesis explores whether or not a billionaire's political power provides them with immunity to federal laws and regulations that govern wealth and its political use. The objective of this research is two-fold: to illustrate the scholarship gap regarding American billionaires and their relative immunity from federal law, and to instigate academia to study billionaires politically at increasing rates, providing more data for lawmakers regarding the most economically powerful political …


Advanced Machine Learning Techniques For Social Support Detection On Social Media, Olga Kolesnikova, Moein Shahiki Tash, Zahra Ahani, Ameeta Agrawal, Raúl Monroy, Grigori Sidorov May 2025

Advanced Machine Learning Techniques For Social Support Detection On Social Media, Olga Kolesnikova, Moein Shahiki Tash, Zahra Ahani, Ameeta Agrawal, Raúl Monroy, Grigori Sidorov

Computer Science Faculty Publications and Presentations

The widespread use of social media highlights the need to understand its impact, particularly the role of online social support. In this study, we present a dataset of YouTube comments, initially comprising 66,272 entries, which was refined to 42,695, with a subset of 10,000 comments selected for detailed analysis without additional filtering. The dataset is annotated for three classification tasks: (1) distinguishing supportive from non-supportive comments, (2) determining whether the support is directed at an individual or a group, and (3) further categorizing group support into six subtypes (Nation, LGBTQ, Black Community, Women, Religion, and Other). To address data imbalances …


Identifying Antimalarials That Disrupt Malaria Parasite Transmission When Fed To The Mosquito, Sarah N. Farrell, Anton Cozijnsen, Vanessa Mollard, Papireddy Kancharla, Rozalia A. Dodean, Jane X. Kelly, Geoffrey I. Mcfadden, Christopher D. Goodman May 2025

Identifying Antimalarials That Disrupt Malaria Parasite Transmission When Fed To The Mosquito, Sarah N. Farrell, Anton Cozijnsen, Vanessa Mollard, Papireddy Kancharla, Rozalia A. Dodean, Jane X. Kelly, Geoffrey I. Mcfadden, Christopher D. Goodman

Chemistry Faculty Publications and Presentations

A decade-long decline in malaria cases has plateaued, primarily due to parasite drug resistance and mosquito resistance to insecticides used in bed nets and indoor residual spraying. Here, we explore the innovative control strategy targeting Plasmodium with antimalarials during the mosquito stages. This strategy has the potential to reduce the risk of resistance emerging because a relatively small population of parasites within the mosquito is subject to selection. After validating mosquito feeding strategies, we screened a range of parasiticidal compounds by feeding them to mosquitoes already infected with mouse malaria (P. berghei). Three antimalarials showed activity against P. berghei in …


Restricted Nonlinear Simulations Of Flow Over Riblets: Characterizing Drag Reduction And Its Breakdown, Xiaowei Zhu, Bianca Fontanin Viggiano, Benjamin A. Minnick, Dennice Gayme May 2025

Restricted Nonlinear Simulations Of Flow Over Riblets: Characterizing Drag Reduction And Its Breakdown, Xiaowei Zhu, Bianca Fontanin Viggiano, Benjamin A. Minnick, Dennice Gayme

Mechanical and Materials Engineering Faculty Publications and Presentations

The restricted nonlinear (RNL) model is employed as low-order representation of turbulent flow over riblets at 𝑅𝑒𝜏 ≈ 395. Comparisons with direct numerical simulations (DNS) verify the ability of the model to accurately capture low-order statistics, as well as trends in drag-alteration and secondary motion as a function of riblet geometry and spacing. We demonstrate the ability of the RNL model to reproduce additional flow features by decomposing the roughness function to isolate contributions from the total stress and comparing its predictions to DNS data. An analysis of the spectra of Reynolds shear stress shows that the RNL model captures …


Helmholtz Cage: Software Development And Implementation For Cubesat Testing, Gustavo A. Cotom Lopez May 2025

Helmholtz Cage: Software Development And Implementation For Cubesat Testing, Gustavo A. Cotom Lopez

University Honors Theses

This paper details the successful development and deployment of a Helmholtz cage system, designed to produce precisely controlled magnetic fields for testing and calibration purposes. The core focus was on creating a robust, modular software architecture enabling independent current modulation on each axis, comprehensive serial communication between multiple microcontrollers, and real-time data acquisition from the MR3 magnetometer. All software components, including the serial communication drivers, control algorithms, command line interface, and calibration routines, were developed from the ground up. The system was fully operational upon completion: all hardware components functioned as intended, serial communication with each subsystem was reliable, and …


A Resource-Based Perspective Of Stem Career Development: A Latent Class Analysis, Erika Ann Schemmel May 2025

A Resource-Based Perspective Of Stem Career Development: A Latent Class Analysis, Erika Ann Schemmel

Dissertations and Theses

Through technological developments and the growing concerns around climate change, the need and demand for electric vehicles has been steadily increasing. A trained and qualified STEM workforce is required to meet these demands, yet standard STEM education may not be sufficient. The STEM development program centered in the present study is a collegiate workforce development program that provides North American students with training and hands-on experience in the engineering of electric vehicles. Drawing from central principles of COR theory, the present study explores the experiences of students within the program utilizing a resource-based perspective and a mixed-methods approach. First, the …


The Role Of Cultural Mathematical Caring Relations In Supporting Two Latina Undergraduates’ Rate Of Change Development Within A Constructivist Teaching Experiment: An Anti-Deficit Investigation Bridging Sensemaking And Cultural Experiences, Christopher Orlando Roman May 2025

The Role Of Cultural Mathematical Caring Relations In Supporting Two Latina Undergraduates’ Rate Of Change Development Within A Constructivist Teaching Experiment: An Anti-Deficit Investigation Bridging Sensemaking And Cultural Experiences, Christopher Orlando Roman

Dissertations and Theses

This study introduces cultural mathematical caring relations (CMCRs) as a framework that extends Hackenberg's mathematical caring relations by integrating two tenets of culturally relevant pedagogy: academic achievement and cultural competence. Framed within radical constructivism, CMCRs prioritize students' cognitive growth and development while affirming their cultural and experiential identities by embedding their funds of knowledge into the learning process. Through a constructivist teaching experiment with two Latina students, Yari and Jocelyn, this research investigates how working to establish and maintain CMCRs can influence Latin* students' rate of change development.

Findings illustrate that CMCRs supported the development of Yari and Jocelyn's rate …


Book Review Of, Participatory Engineering Of Algorithmic Socialtechnologies: An Extended Book Review Of David G. Robinson's Voices Inthe Code, Rajesh Venkatachalapathy May 2025

Book Review Of, Participatory Engineering Of Algorithmic Socialtechnologies: An Extended Book Review Of David G. Robinson's Voices Inthe Code, Rajesh Venkatachalapathy

Complex Systems Faculty Publications and Presentations

David G. Robinson’s Voices in the Code, reviewed here, approaches the issue of governance and regulation of algorithmic social technologies with a case study orientation that offers a grounding in the details, illuminating the fundamentally sociological and processual nature of modern governance issues that are mostly missed or left implicit in academic, regulatory, and legislative discussions. This important book urges us to design adaptive, malleable, and evolvable participatory organizational structures instead. Accepting the author’s invitation to carry the torch forward, this review builds on and extends the book’s arguments by presenting broad and transferable insights on regulation and governance …


Detecting And Analyzing Frequency Events In Power Systems Using Tunable Parameters-Based Algorithms: Development, Optimization, And Analysis, Hussain A. Alghamdi May 2025

Detecting And Analyzing Frequency Events In Power Systems Using Tunable Parameters-Based Algorithms: Development, Optimization, And Analysis, Hussain A. Alghamdi

Dissertations and Theses

This dissertation addresses the challenge of detecting frequency events in diverse power systems by enhancing existing frequency event detection methods through detection process modifications and developing unique tunable parameters. Since system characteristics differ across regions, frequency event detection algorithms must be customized by domain experts for each balancing area using tunable parameters. By optimizing these parameters for specific power system, the algorithms can accurately detect frequency events and can also be used for further analysis to determine trends in frequency events over time, ensuring system stability.

This dissertation focuses on the enhancement and optimization of frequency event detection algorithms. These …


Institutions, Indigenous Peoples, And The Structure Of Power In Columbia River Basin Salmon Governance, Christopher Michael Page May 2025

Institutions, Indigenous Peoples, And The Structure Of Power In Columbia River Basin Salmon Governance, Christopher Michael Page

Dissertations and Theses

As broad patterns of behavior influenced by norms and rules, institutions structure many aspects of modern society through coordination and the distribution of power. Due to the importance of common-pool natural resources to many aspects of society, they usually involve competition and lie at the intersection of multiple institutions. This combination of institutions, power disparities, and a competitive interest is what scholars have referred to as a "field." Fields can be complex, and the coordination among interests is generally done through a form of governance involving a wide array of laws, regulations, and actors. When at least one of these …


Deep Learning Classification Of Drainage Crossings Based On High-Resolution Dem-Derived Geomorphological Information, Michael Edidem, Bill Xu, Ruopu Li, Di Wu, Banafsheh Rekabdar, Guangxing Wang May 2025

Deep Learning Classification Of Drainage Crossings Based On High-Resolution Dem-Derived Geomorphological Information, Michael Edidem, Bill Xu, Ruopu Li, Di Wu, Banafsheh Rekabdar, Guangxing Wang

Computer Science Faculty Publications and Presentations

High-resolution digital elevation models (HRDEMs) from LiDAR and InSAR technologies have significantly improved the accuracies of mapping hydrographic features such as river boundaries, streamlines, and waterbodies over large areas. However, drainage crossings that facilitate the passage of drainage flows beneath roads are not often represented in HRDEMs, resulting in erratic or distorted hydrographic features. At present, drainage crossing datasets are largely missing or available with variable quality. While previous studies have investigated basic convolutional neural network (CNN) models for drainage crossing characterization, it remains unclear if advanced deep learning models will improve the accuracy of drainage crossing classification. Although HRDEM-derived …


Enabling New Synthetic Platforms For Aryne Synthesis With Aryl Thianthrenium Reagents, Riley Augustus Roberts May 2025

Enabling New Synthetic Platforms For Aryne Synthesis With Aryl Thianthrenium Reagents, Riley Augustus Roberts

Dissertations and Theses

The enormous importance of aromatic rings in organic molecules cannot be understated. Aromatic rings are present in the majority of pharmaceuticals, agrochemicals, and consumer products. The way in which these rings are arranged and substituted results in a molecule’s unique properties. Because of this, the current limitations of the chemical methods used to synthesize these molecules results in limited structural diversity and thus missed opportunities for the development of value-added products. To this end, this work demonstrates novel methods of aryne synthesis, aryl thianthrenium synthesis and a unique approach to structural scaffold hopping. The approaches presented herein allow for rapid …


Magma Evolution And Eruptive History Of Three Fingered Jack: A Mafic Composite Volcano In The Central High Cascades Of Oregon, Javaria Aziz May 2025

Magma Evolution And Eruptive History Of Three Fingered Jack: A Mafic Composite Volcano In The Central High Cascades Of Oregon, Javaria Aziz

Dissertations and Theses

The central High Cascades graben in Oregon has been a center for mafic volcanism since its initiation. Three Fingered Jack is one of the larger mafic composite cones in the graben, located 20km south of Mount Jefferson. Three Fingered Jack erupted between 142.1 - 150.8ka, based on Ar40/Ar39 age dates. This study provides stratigraphic, compositional and petrographic evidence to understand the eruptive history of Three Fingered Jack and the processes involved in generating compositionally diverse basaltic andesites here.

The basaltic andesites of Three Fingered Jack show three compositional trends of magma evolution: 1) enrichment, 2) depletion and …


Weak Formulation For Solving Inverse Problems In Reproducing Kernel Hilbert Spaces (With Applications To Learning Dynamical Systems), Victor William Rielly May 2025

Weak Formulation For Solving Inverse Problems In Reproducing Kernel Hilbert Spaces (With Applications To Learning Dynamical Systems), Victor William Rielly

Dissertations and Theses

We combine numerical and machine learning techniques to present a general framework for solving inverse problems using vector valued reproducing kernel Hilbert spaces in a variational formulation. We present this framework in two papers. In the first paper, we present an original state-of-the-art method derived in the context of our general framework for learning dynamical systems. In the second paper, we generalize the method from our first paper to arrive at the framework for solving inverse problems. Then we apply our general framework to the task of learning dynamical systems. In both papers we consider numerous applications of our methods …


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 May 2025

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 May 2025

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 …


Cuju: The Ancient Chinese Game That Held An Empire Together, Enzo H. Smith Apr 2025

Cuju: The Ancient Chinese Game That Held An Empire Together, Enzo H. Smith

Young Historians Conference

This paper explores how cuju, an ancient sport known as the predecessor of modern football, evolved from the Han to Song dynasties (206 BCE–1368 CE) as a unifying force in imperial China. Calling upon primary sources such as ancient cuju manuals and various art pieces suggests this sport's importance went beyond a leisurely practice. Using academic journals about Chinese history and the development of cuju from different academic fields and, most notably, the FIFA museum’s online exhibit of cuju, the reason cuju had such a strong place of value in Chinese society was apparent. Beginning as a combat exercise in …


The Roots Of Ethno-Political Strife In Ceylon: The Dividing Power Of British Colonialism, Audrey Francioch Apr 2025

The Roots Of Ethno-Political Strife In Ceylon: The Dividing Power Of British Colonialism, Audrey Francioch

Young Historians Conference

A bloody civil war has rocked Sri Lanka for decades, as the Sinhalese and Tamil populations fight each other for recognition, access, and control. Since the 1950s, each group has feared domination by the other, resulting in bitter battles on the ballots and in the streets to assert or retain power and subjugate the culture of the other. Each conflict perpetuates the vicious circle of retaliation and retribution through the generations, and the roots of this divide can be directly traced to the colonial occupation of the island in the 1800s. What began with the Dutch and became refined by …


Form Follows Function: An Analysis Of De Architectura And Its Influence, Weston Klein Apr 2025

Form Follows Function: An Analysis Of De Architectura And Its Influence, Weston Klein

Young Historians Conference

Over 2000 years ago, the Roman architect and engineer, Marcus Vitruvius Pollio, scribed De Architectura, a multi-volume work unearthed in the 15th century, in St. Gallen, Switzerland. As the only surviving architectural source from antiquity, the book has been indispensable in the study of Greco-Roman architecture, positioning Vitruvian and Greco-Roman architectural concepts in many ways as one in the same. Additionally, Vitruvian ideas, as expressed in De Architectura, regarding architectural form, materials, location, and process have been foundational to the evolution of Western architecture. This paper explores De Architectura’s impact on Western architectural theory and practice spanning the Early Middle …


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 Apr 2025

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 …


Estimated Amounts Of Terrestrial Carbon Mobilized And Sequestered By The 1980 Mount St. Helens Eruption, Washington State, Usa, Lizzet G. Reyes Apr 2025

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 …