Stability Of Retinol In Liposomes As Measured By Fluorescence Lifetime Spectroscopy And Flim, Louis Sumrall, L. Smith, Elmukhtar Ehmed Alhatmi, Yekaterina G. Chmykh, D. Mitchell, Jay Nadeau

Physics Faculty Publications and Presentations

Retinol shows complex photophysical properties that make it potentially useful as an exogenous or endogenous probe of membrane microenvironment, but it has not been fully explored. In this study, we use bulk fluorescence lifetime measurements and fluorescence lifetime imaging microscopy (FLIM) to examine the stability of retinol in phosphatidylcholine (PC) multilamellar and unilamellar vesicles with and without cholesterol. We find that both light and exposure to ambient temperature and oxygen contribute to retinol degradation, with the addition of an antioxidant such as butylated hydroxytoluene (BHT) essential to provide stability, especially in the absence of cholesterol. With exposure to ultraviolet light …

A Hierarchical Decision Model To Evaluate Healthcare Organization's Readiness To Implement Clinical Decision Support Systems, Mohammed Oussama Laraichi

Dissertations and Theses

Clinical Decision Support Systems (CDSS) are essential tools for healthcare organizations as well as for healthcare providers to improve clinical care. However, successful implementation of CDSS can be challenging. Therefore, before implementing CDSS, it is crucial to assess the readiness of healthcare organizations to implement these tools.

Through a literature review, the first step of this research explores the concept of clinical decision support and CDSS, discussing their features, characteristics, and organizational hurdles to implementation. It also provides perspectives on CDSS adoption in the context of Information Systems and Health Technology. The review helped identify research gaps, objectives, and questions. …

Willow Abundance And Condition Mapping In Rocky Mountain National Park, Eric M. Nielsen

Institute for Natural Resources Publications

Riparian and wetland willow species have undergone serious declines in Rocky Mountain National Park as a consequence of a variety of environmental changes and, most recently, damage resulting from moose overpopulation. To address concerns about the long-term status of willows in the park, we developed remote sensing-based raster maps of riparian and wetland willow species presence, canopy cover percentage, canopy height, and leaf area index. All outputs were produced at 3-meter resolution, and represent willows as they existed in 2021. The mapping was performed via random forests classification and regression models trained on several hundred vegetation plots from a variety …

Developing A Sample-Efficient Analytical Pathway For A Qualitative Chemical Investigation Of Ancestral Chilkat Dyeing And Weaving Practices, Dario Gerlando Durastanti

Dissertations and Theses

The project goal is to identify the dyestuffs used in hand-woven Chilkat blankets from the collection of the Alaska State Museum and the Sheldon Jackson Museum. Chilkat weaving is practiced by Northwest coastal clans, particularly in Southeast Alaska since at least the early 19th century. Through this collaboration, 117 wool fibers from 23 Chilkat textiles, and 193 reference samples consisting of dyed fibers using both natural and synthetic dye sources, raw dye material, and dye bath aliquots were provided to the lab for reference characterization and identification. In these analyses, dyes were classified as being either natural or synthetic, subdivided …

A Gridded Co2 Emissions Inventory For Portland, Or, James E. Powell

Dissertations and Theses

Here we develop a new high resolution inventory of CO₂ emissions for the three Oregon counties which comprise the bulk of the City of Portland, Oregon, USA. Locally curated and long-running data collection efforts for on-road traffic activity and emission rates are used to model on-road emissions, and a new survey of the area's natural gas network informs the building energy model. The inventory estimates total emissions of CO₂ for each hour of the year 2018 in the on-road, residential, and commercial building sectors at 1 km² resolution. The onroad inventory compares to within 3% with an …

Implementing A Functional Logic Programming Language Via The Fair Scheme, Andrew Michael Jost

Dissertations and Theses

This document presents a new compiler for the Functional Logic programming language Curry based on a novel pull-tabbing evaluation strategy called the Fair Scheme. A simple version of the Fair Scheme is proven sound, complete, and optimal. An elaborated version is also developed, which supports narrowing computations and other features of Curry, such as constraint programming, equational constraints, and set functions.

The Fair Scheme is used to develop a new Curry system called Sprite, a high-quality, performant implementation whose aims are to promote practical uses of Curry and to serve as a laboratory for further research. An important aspect of …

Phytoplankton Community As An Indicator Of Cyanobacteria Harmful Algal Blooms In High Mountain Lakes, Victoria Elizabeth Avalos

Dissertations and Theses

Cyanobacteria blooms are a growing issue worldwide and can be harmful to both aquatic life and human health. Warm temperatures, nutrient loading, stable water columns, and selective grazing of zooplankton and phytoplankton can contribute to cyanobacteria bloom formation. In this study, I characterized the algal communities and water quality differences in two physiographically similar lakes with relatively little human influences, Odell and Crescent Lakes, Oregon, to better understand potential contributing factors to cyanobacteria harmful algal bloom formation (cyanobacteria bloom) in Odell Lake.

There are three hypotheses in this study:

1. If there was a cyanobacteria bloom in Odell Lake, but not …

Caspi: Collaborative Photon Processing For Active Single-Photon Imaging, Jongho Lee, Atul Ingle, Jenu V. Chacko, Kevin W. Eliceiri, Mohit Gupta

Computer Science Faculty Publications and Presentations

Image sensors capable of capturing individual photons have made tremendous progress in recent years. However, this technology faces a major limitation. Because they capture scene information at the individual photon level, the raw data is sparse and noisy. Here we propose CASPI: Collaborative Photon Processing for Active Single-Photon Imaging, a technology-agnostic, application-agnostic, and training-free photon processing pipeline for emerging high-resolution single-photon cameras. By collaboratively exploiting both local and non-local correlations in the spatio-temporal photon data cubes, CASPI estimates scene properties reliably even under very challenging lighting conditions. We demonstrate the versatility of CASPI with two applications: LiDAR imaging over a …

Divergence-Conforming Velocity And Vorticity Approximations For Incompressible Fluids Obtained With Minimal Facet Coupling, Jay Gopalakrishnan, Lukas Kogler, Philip L. Lederer, Joachim Schöberl

Mathematics and Statistics Faculty Publications and Presentations

We introduce two new lowest order methods, a mixed method, and a hybrid discontinuous Galerkin method, for the approximation of incompressible flows. Both methods use divergence-conforming linear Brezzi–Douglas–Marini space for approximating the velocity and the lowest order Raviart–Thomas space for approximating the vorticity. Our methods are based on the physically correct viscous stress tensor of the fluid, involving the symmetric gradient of velocity (rather than the gradient), provide exactly divergence-free discrete velocity solutions, and optimal error estimates that are also pressure robust. We explain how the methods are constructed using the minimal number of coupling degrees of freedom per facet. …

Evapotranspiration Of Residential Lawns Across The United States, Noortje H. Grijseels, Elizaveta Litvak, Meghan Avolio, Anika R. Bratt, Jeannine Cavender-Bares, Peter M. Groffman, Sarah E. Hobbie, Susannah B. Lerman, Jennifer L. Morse, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

Despite interest in the contribution of evapotranspiration (ET) of residential turfgrass lawns to household and municipal water budgets across the United States, the spatial and temporal variability of residential lawn ET across large scales is highly uncertain. We measured instantaneous ET (ET_inst) of lawns in 79 residential yards in six metropolitan areas: Baltimore, Boston, Miami, Minneapolis-St. Paul (mesic climates), Los Angeles and Phoenix (arid climates). Each yard had one of four landscape types and management practices: traditional lawn-dominated yards with high or low fertilizer input, yards with water-conserving features, and yards with wildlife-friendly features. We measured ET_{inst …}

A Pattern-Centered Analysis Of Adolescents' Concerns And Hopes About Future Crises: Differences In Ways Of Coping And Personal Adjustment, Melanie J. Zimmer-Gembeck, Katheryn L. Modecki, Ellen Skinner, Lara J. Farrell, Tanya Hawes

Psychology Faculty Publications and Presentations

Introduction

Many adolescents are concerned about global and future crises, such as the health of the planet or terrorism/safety. Yet, adolescents can also express hope about the future. Thus, asking adolescents about their concern and hope could yield subgroups with different ways of coping and personal adjustment.

Method

Australian adolescents (N = 863; age 10-16) completed surveys to report their concern (worry and anger) and hope about the planet, safety, jobs, income, housing, and technology, as well as their active and avoidant coping, depression, and life satisfaction.

Results

Four distinct subgroups were identified using cluster analysis: Hopeful (low on concern …

A Unified Understanding Of Minimum Lattice Thermal Conductivity, Yi Xia, Dale Gaines, Jiangang He, Koushik Pal, Zhi Li, Mercouri G. Kanatzidis, Vidvuds Ozolinš, Chris Wolverton

Mechanical and Materials Engineering Faculty Publications and Presentations

We propose a first-principles model of minimum lattice thermal conductivity based on a unified theoretical treatment of thermal transport in crystals and glasses.

Quantum Multi-Solution Bernoulli Search With Applications To Bitcoin’S Post-Quantum Security, Alexandru Cojocaru, Juan Garay, Fang Song, Petros Wallden

Computer Science Faculty Publications and Presentations

A proof of work (PoW) is an important cryptographic construct which enables a party to convince other parties that they have invested some effort in solving a computational task. Arguably, its main impact has been in the setting of cryptocurrencies such as Bitcoin and its underlying blockchain protocol, which have received significant attention in recent years due to its potential for various applications as well as for solving fundamental distributed computing questions in novel threat models. PoWs enable the linking of blocks in the blockchain data structure, and thus the problem of interest is the feasibility of obtaining a sequence …

Glacialwater: A Dynamic Microbial Medium, Gilda Varliero, Pedro H. Lebre, Andrew G. Fountain, Beat Frey, Alexandre M. Anesio, Don A. Cowan

Geology Faculty Publications and Presentations

Microbial communities and nutrient dynamics in glaciers and ice sheets continuously change as the hydrological conditions within and on the ice change. Glaciers and ice sheets can be considered bioreactors as microbiomes transform nutrients that enter these icy systems and alter the meltwater chemistry. Global warming is increasing meltwater discharge, affecting nutrient and cell export, and altering proglacial systems. In this review, we integrate the current understanding of glacial hydrology, microbial activity, and nutrient and carbon dynamics to highlight their interdependence and variability on daily and seasonal time scales, as well as their impact on proglacial environments.

Room 1: Getting Started With Oer, Cheryl Cuillier

Open Educational Resources Symposium

Are you new to open educational resources and want to learn more? This webinar covers the basics:

• Why high textbook costs are a problem for students
• How OER differ from free resources
• How Creative Commons licenses work
• Where to find OER
• What resources are available for customizing OER
• How to incorporate open pedagogy into a class

Presenter Cheryl Cuillier shares a wealth of resources to help kick-start your adoption, adaptation, or creation of OER.

Room 1: Beginners Welcome!

Zoom Link: https://linnbenton.zoom.us/j/92808750724

Global Water Level Variability Observed After The Hunga Tonga-Hunga Ha’Apai Volcanic Tsunami Of 2022, Adam Thomas Devlin, David A. Jay, Stefan Talke, Jiayi Pan

Civil and Environmental Engineering Faculty Publications and Presentations

The eruption of the Hunga Tonga-Hunga Ha'apai volcano on 15 January 2022 provided a rare opportunity to understand global tsunami impacts of explosive volcanism and to evaluate future hazards, including dangers from “volcanic meteotsunamis” (VMTs) induced by the atmospheric shock waves that followed the eruption. The propagation of the volcanic and marine tsunamis was analyzed using globally distributed 1 min measurements of air pressure and water level (WL) (from both tide gauges and deep-water buoys). The marine tsunami propagated primarily throughout the Pacific, reaching nearly 2 m at some locations, though most Pacific locations recorded maximums lower than 1 m. …

A Double Edged Blade: Contrasting Theories Of Dissection Within 16th Century Italy, Sarah Zdebski

Young Historians Conference

Up until the Middle Ages, dissection was largely nonexistent. Gory and unsettling to the modern eye, physicians and anatomists alike agreed that animal dissections and comparative anatomies were more than sufficient to map out the human body. When academic dissections did begin to occur with regularity, they were rigid and formal in nature, relying on inaccurate anatomical texts written over a millennia ago by the Greek physician Galen. Dissection was a visual exercise, conducted primarily in Italian universities to provide a gory illustration for the medical student. The established format for dissection at the beginning of the 16^th century …

Impacts Of Floodplain Restoration On Water Temperature And Macroinvertebrates In Whychus Creek, Oregon, Wesley Nathan Noone

Dissertations and Theses

Stream restoration is a proposed climate adaptation tool, however, outcomes of floodplain restoration on stream temperature have been debated. Despite a growing number of studies that investigated water temperature in restored streams, few have quantified thermal heterogeneity in new habitat types created by restored hydrogeomorphic processes and the impact of thermal diversity on the aquatic macroinvertebrate community. In this study, I evaluated three hypotheses: 1) restoration increases habitat diversity, 2) habitat diversity increases water temperature heterogeneity, and 3) restored reaches have more diverse macroinvertebrate communities. I collected a total of 40 macroinvertebrate samples and characterized environmental conditions in three reaches …

Faculty Senate Monthly Packet April 2023, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The April 3, 2023 Monthly packet includes the April agenda and appendices and the Faculty Senate minutes and attachments from the meeting held March 6, 2023.

Ce-Qual-W2 Performance Assessment Modeling 1979 Grh Flume Study, Logan Negherbon

Civil and Environmental Engineering Master's Project Reports

In an early review of numerical reservoir hydrodynamic models, the US Army Corps of Engineers developed a physical model at the US Army Waterways Experiment Station to assess the performance of modeling cold water underflow with numerous 2-dimensional and 3-dimensional numerical hydrodynamic models. Within this effort, the precursor for CE-QUAL-W2, the Laterally Averaged Reservoir Model, was defined and applied with limited success in representing the vertical velocity profile and outflow temperatures series collected from the physical model in the General Reservoir Hydrodynamics flume. CE-QUAL-W2 has since been modified from this early form in numerous ways including incorporation of higher order …

Detecting Fast Frequency Events In Power System: Development And Comparison Of Two Methods, Hussain A. Alghamdi, Midrar Adham, Umar Farooq, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

In power systems, frequency deviation from nominal value can occur due to reasons such as loss of generation, loss of load, or major faults in the grid. Such frequency fluctuations can lead to serious subsequent outages and damages to both end-user and utility equipment. Therefore, a proper frequency deviation detection methodology must be in place to effectively identify frequency events in a timely manner. This manuscript provides a comparative analysis between two frequency deviation detection algorithms. One is based on signal processing and statistical analysis. The other is a regression-based algorithm. Both of these algorithms have multiple adjustable parameters, making …

Cyclic Behavior Of Transitional Fine-Grained Soils In Northern Willamette Valley, Frank Jarman

Civil and Environmental Engineering Master's Project Reports

As discussed within studies from Idriss and Boulanger (2008) and Bray and Sancio (2006), the undrained cyclic shear behavior of low-plasticity fine-grained soils will transition between liquefaction (sand-like behavior) to cyclic softening (clay-like behavior) over a narrow range of plasticity index (PI). Despite not being sufficiently understood, the cyclic behavior of low plasticity silts has become an increasingly important field of study due to the significant impact it has on ground deformations and infrastructure failure in areas that are seismically active. Laboratory tests were performed on soils by third party consultants on a site located in the northern Willamette Valley, …

Longitudinal Changes In Alzheimer’S-Related Plasma Biomarkers And Brain Amyloid, Murat Bilgel, Abhay Moghekar, Henrik Zetterberg, Bruno Jedynak, Multiple Additional Authors

Mathematics and Statistics Faculty Publications and Presentations

Introduction Understanding longitudinal plasma biomarker trajectories relative to brain amyloid changes can help devise Alzheimer’s progression assessment strategies.

Methods We examined the temporal order of changes in plasma amyloid-β ratio (Aβ42/Aβ40), glial fibrillary acidic protein (GFAP), neurofilament light chain (NfL), and phosphorylated tau ratios (p-tau181/Aβ42, p-tau231/Aβ42) relative to 11C-Pittsburgh compound B (PiB) positron emission tomography (PET) cortical amyloid burden (PiB−/+). Participants (n = 199) were cognitively normal at index visit with a median 6.1-year follow-up.

Results PiB groups exhibited different rates of longitudinal change in Aβ42/Aβ40 (β = 5.41 × 10-4, SE = 1.95 × 10-4, p = 0.0073). …

Management Plan For The Western Painted Turtle At The Sandy River Delta In Troutdale, Oregon, Emma Scott

Environmental Science and Management Professional Master's Project Reports

This management plan has been prepared for the Lower Columbia Estuary Partnership and is intended to provide guidance for the improvement and protection of western painted turtle (Chrysemys picta bellii) habitat at the Sandy River Delta in Troutdale, Oregon. The Sandy River Delta is a 1500-acre natural area situated where the Columbia and Sandy Rivers meet. Its dynamic floodplain habitat supports a diverse assemblage of species, including the western painted turtle, an Oregon Conservation Strategy Species. A small, unknown number of western painted turtles utilize the wetland habitats of the Sandy River Delta, and the frequency in observations …

An Examination Of The Current Knowledge Of Contaminants In Mangroves: Hawaii And Globally, Geoffrey Szafranski

Environmental Science and Management Professional Master's Project Reports

The geographic range of mangrove forests is shifting quickly as they expand poleward in response to climate change while simultaneously being removed from their native extent to clear space for anthropogenic land-uses. Mangrove forests are also known to be sinks for anthropogenic contamination. Yet contamination research is under-researched in mangrove ecosystems, specifically the environmental fate, effect on biodiversity, and risk to human populations from contamination in the context of these changing conditions requires further research. The goal of this thesis is to address this data gap through analysis of contamination in the literature and through an investigational survey of mangrove …

Realization Of Multi-Valued Logic Using Optical Quantum Computing, Sophie Choe

Dissertations and Theses

Quantum computing is a paradigm of computing using physical systems, which operate according to quantum mechanical principles. Since 2017, functioning quantum processing units with limited capabilities are available on the cloud. There are two models of quantum computing in the literature: discrete variable and continuous variable models. The discrete variable model is an extension of the binary logic of digital computing with quantum bits |0⟩ and |1⟩ . In the continuous variable model, the quantum state space is infinite-dimensional and the quantum state is expressed with an infinite number of basis elements.

In the physical implementation of quantum computing, however, …

Studies On Bonding, Syntheses, And Applications Of Diarylhalonium Compounds, Shubhendu Karandikar

Dissertations and Theses

Organic compounds containing functionalized benzenoid rings have found tremendous applications in pharmaceuticals, agrochemicals, commodity chemicals, and beyond. As a result, development of methods for the synthesis of functionalized benzenoid rings has gained much attention from the synthetic community. Although many transition-metal mediated methods to functionalize benzenoid rings are known, there has been an upsurge of activity in developing protocols for decoration of benzenoid cores promoted by p-block elements. This excitement stems from the sustainability of earth-abundant elements and unique reactivity patterns observed within the p-block. Among these, transformations promoted by hypervalent halogen compounds, and especially, the diarylhalonium salts are very …

7-Deazaguanines In Dna: Functional And Structural Elucidation Of A Dna Modification System, Samanthi Herath Gedara, Andrew Gustafson, Dirk Iwata-Reuyl, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

The modified nucleosides 2′-deoxy-7-cyano- and 2′-deoxy-7-amido-7-deazaguanosine (dPreQ₀ and dADG, respectively) recently discovered in DNA are the products of the bacterial queuosine tRNA modification pathway and the dpd gene cluster, the latter of which encodes proteins that comprise the elaborate Dpd restriction–modification system present in diverse bacteria. Recent genetic studies implicated the dpdA, dpdB and dpdC genes as encoding proteins necessary for DNA modification, with dpdD–dpdK contributing to the restriction phenotype. Here we report the in vitro reconstitution of the Dpd modification machinery from Salmonella enterica serovar Montevideo, the elucidation of the roles of each protein and the X-ray …

Toward Efficient Rendering: A Neural Network Approach, Qiqi Hou

Dissertations and Theses

Physically-based image synthesis has attracted considerable attention due to its wide applications in visual effects, video games, design visualization, and simulation. However, obtaining visually satisfactory renderings with ray tracing algorithms often requires casting a large number of rays and thus takes a vast amount of computation. The extensive computational and memory requirements of ray tracing methods pose a challenge, especially when running these rendering algorithms on resource-constrained platforms, and impede their applications that require high resolutions and refresh rates. This thesis presents three methods to address the challenge of efficient rendering.

First, we present a hybrid rendering method to speed …

Tools For Quantifying Bacterial Motility Using Digital Holographic Microscopy As Applied To Studying The Simulated Microgravity Environment, Jacqueline Marie Acres

Dissertations and Theses

Digital holographic microcopy (DHM) is a label-free technique that has gained attention in recent years as a tool for volumetric imaging. One application of DHM is for the study of microbial motility with the advantage being that organisms may freely move within their environment. Images created from DHM are in the form of holograms. Holograms are time recordings showing XY information with the Z information contained within. Z information can be retrieved from the holograms directly through a variety of numerical techniques or through reconstruction. Datasets generated from DHM are large and processing remains a challenging task. Here, we show …