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Full-Text Articles in Physical Sciences and Mathematics

Centering Equity In Oregon’S 100 Year Water Vision: A Student-Led Policy Paper Prepared By The Oregon Water Stories Team At Portland State University, Clare T. Mcclellan, Sadie Boyers, Victoria Cali De Leon, Tony Cole, Laura Cowley-Martinson, Shersten Finley, Dustin Lanker, Julia Seydel, Aakash Nath Upraity, Janet Cowal, Melissa Haeffner Jan 2020

Centering Equity In Oregon’S 100 Year Water Vision: A Student-Led Policy Paper Prepared By The Oregon Water Stories Team At Portland State University, Clare T. Mcclellan, Sadie Boyers, Victoria Cali De Leon, Tony Cole, Laura Cowley-Martinson, Shersten Finley, Dustin Lanker, Julia Seydel, Aakash Nath Upraity, Janet Cowal, Melissa Haeffner

Environmental Science and Management Faculty Publications and Presentations

The purpose of this report is to provide evidence for the need to further intentionally incorporate equity into Oregon’s 100 Year Water Vision. Four case studies contextualize this need and highlight the variety of water issues throughout the state, supported by linguistic analyses of local newspapers. As Oregon policy-makers are responsible for ensuring working water systems for all Oregonians, we also suggest implementable criteria for the evaluation of equity in water issues and decision-making. This student-led and interdisciplinary report comes from the Haeffner-Cowal Oregon Water Stories research lab at Portland State University.


Pine Rosin As A Toxic Cannabis Extract Adulterant, Jiries Meehan-Attrash, Robert Strongin Jan 2020

Pine Rosin As A Toxic Cannabis Extract Adulterant, Jiries Meehan-Attrash, Robert Strongin

Chemistry Faculty Publications and Presentations

Pine rosin (colophony) has been identified as a new adulterant in cannabis oil. Its inhalation toxicity poses a significant health concern to users. For example, pine rosin fumes are released during soldering, and have been cited as a causative agent of occupational asthma. Symptoms also include desquamation of bronchial epithelium, which has also been observed in EVALI patients. The sample analyzed herein was acquired from a cannabis industry source, also contains medium chain triglycerides and oleamide, the latter of which is a hypnotic that is commonly found in the synthetic marijuana product Spice, or K2. A combination of NMR and …


Modeling Spatiotemporal Patterns Of Pm2.5 At The Sub-Neighborhood Scale Using Low-Cost Sensor Networks, Philip Jeffrey Orlando Jan 2020

Modeling Spatiotemporal Patterns Of Pm2.5 At The Sub-Neighborhood Scale Using Low-Cost Sensor Networks, Philip Jeffrey Orlando

Dissertations and Theses

Epidemiological research has demonstrated an adverse relationship between fine particulate matter (PM2.5) and human health. While PM2.5 continues to pose a significant global health risk, there is still the need to further characterize exposures at the intra-urban scale. Land use regression is a statistical modeling technique which is used to predict air pollution concentrations at high resolution from a limited number of monitoring sites. However, the existing regulatory monitoring networks are typically not dense enough to apply these techniques. We explored the potential of using low-cost PM2.5 sensor networks to overcome the limitations of the existing …


Applications Of Triplet-Photosensitizers And Development Of Photochemical Methods, Luke V. Lutkus Jan 2020

Applications Of Triplet-Photosensitizers And Development Of Photochemical Methods, Luke V. Lutkus

Dissertations and Theses

Photochemistry focuses on various aspects of the interaction of light with molecules. This work entails new methodology for fundamental measurements of photochemistry along with novel applications of triplet-photosensitizers. Herein described are two separate methodologies developed for the determination of the quantum yield. A method for the singlet oxygen quantum yield was developed that utilizes the reaction between singlet oxygen and dimethyl sulfoxide (DMSO) to produce dimethyl sulfone. The rate of the reaction is measured by the pressure decrease that results from the consumption of oxygen from the headspace of a sealed system. It was found that the rate of pressure …


Microplastics In Aquatic Organisms: Improving Understanding And Identifying Research Directions For The Next Decade, Elise F. Granek, Susanne Brander, E. B. Holland Jan 2020

Microplastics In Aquatic Organisms: Improving Understanding And Identifying Research Directions For The Next Decade, Elise F. Granek, Susanne Brander, E. B. Holland

Environmental Science and Management Faculty Publications and Presentations

The study of environmental microplastics has increased over the past decade, with hundreds of new studies and resultant papers on the presence, fate, and sources of microplastics in marine and freshwater systems (Fig. 1). Despite the explosion of interest in the topic and in comparison to the research on the presence of microplastics in marine or fresh waters, there have been notably fewer studies on the extent to which these debris items are ingested by aquatic organisms and far fewer on the potential consequences, or response to their presence in organismal guts, tissues, and food webs. Even less research has …


Statistical Analysis Of Social Network Change, Teresa D. Schmidt Jan 2020

Statistical Analysis Of Social Network Change, Teresa D. Schmidt

Systems Science Friday Noon Seminar Series

We explore two statistical methods that infer social network structures and statistically test those structures for change over time: regression-based differential network analysis (R-DNA) and information theory-based differential network analysis (I-DNA). RDNA is adapted from bioinformatics and I-DNA employs reconstructability analysis. Both methods are used to analyze Medicaid claims data from one-year periods before and after the formation of the Health Share of Oregon Coordinated Care Organization (CCO). We hypothesized that Health Share’s CCO formation would be followed by several changes in the healthcare delivery network.

Application of R-DNA and I-DNA to claims data involves three steps: (a) the inference …


Geochemical Response To Thermal Energy Storage In The Columbia River Basalt Aquifer System Beneath The Portland Basin, Oregon, Ellen Elizabeth Svadlenak Jan 2020

Geochemical Response To Thermal Energy Storage In The Columbia River Basalt Aquifer System Beneath The Portland Basin, Oregon, Ellen Elizabeth Svadlenak

Dissertations and Theses

Deep direct use thermal energy storage (TES) is a low carbon emission method of geothermal energy storage and supply for large-scale residential, commercial, and manufacturing heating and cooling. The process entails repeated cycles of hot- or cold-water injection, storage, and extraction from slow groundwater flow zones within the deeper layers of an aquifer system. Though a promising technology, TES cycles may increase mineral dissolution and precipitation reactions, particularly at elevated temperatures. The ensuing mass transfer can form scale in heat exchange systems and alter aquifer porosity and permeability, processes that can reduce the operational efficiency of a TES system.

Within …


Glacial Meltwater Modeling To Simulate Lake Water Budget (1996-2013) In Taylor Valley, Antarctica, Julian Michael Cross Jan 2020

Glacial Meltwater Modeling To Simulate Lake Water Budget (1996-2013) In Taylor Valley, Antarctica, Julian Michael Cross

Dissertations and Theses

The McMurdo Dry Valleys (MDV), the largest ice-free region (4,500 km2) in Antarctica, are a polar desert with an average annual temperature of -18ºC. In Taylor Valley, one of the MDV, closed-basin, perennially ice-covered lakes occupy the valley floor. Their water balance is controlled by inflow from glacial meltwater runoff and loss due to sublimation, making them sensitive indicators of climate. In this study, a physically-based model of glacier meltwater and lake ice sublimation is adapted to explain modern (1996 to 2013) lake-level variations. Meltwater model results were improved by the inclusion of MODIS remotely-sensed albedo measurements (E …


Stars Annual Report, 2020, Campus Sustainability Office Jan 2020

Stars Annual Report, 2020, Campus Sustainability Office

Campus Sustainability Office Publications, Reports and Presentations

The Campus Sustainability Office (CSO) compiles information from departments across campus annually to complete the STARS Report. The score is based on the number of points received across five categories: Academics, Engagement, Operations, and Planning & Administration, and Innovation & Leadership. PSU has maintained a Gold rating since the institution began reporting in 2011 and is within the top 40 of over 400 reporting institutions. This summary includes improvement opportunities to assist our efforts to eventually become a STARS Platinum institution. For more information on improvement opportunities please contact Amanda Wolf at wolf@pdx.edu


Utility Summary Fiscal Year 2020, Campus Sustainability Office Jan 2020

Utility Summary Fiscal Year 2020, Campus Sustainability Office

Campus Sustainability Office Publications, Reports and Presentations

Energy usage listed by building.


Real-Time Evaluation Of City–University Partnerships For Sustainability And Resilience, Liliana Elizabeth Caughman, Lauren Withycombe Keeler, Fletcher Beaudoin Jan 2020

Real-Time Evaluation Of City–University Partnerships For Sustainability And Resilience, Liliana Elizabeth Caughman, Lauren Withycombe Keeler, Fletcher Beaudoin

Institute for Sustainable Solutions Publications and Presentations

Cities face many challenges in their efforts to create more sustainable and resilient urban environments for their residents. Among these challenges is the structure of city administrations themselves. Partnerships between cities and universities are one way that cities can address some of the internal structural barriers to transformation. However, city–university partnerships do not necessarily generate transformative outcomes, and relationships between cities and universities are complicated by history, politics, and the structures the partnerships are attempting to overcome. In this paper, focus groups and trial evaluations from five city–university partnerships in three countries are used to develop a formative evaluation tool …


A Basilosaurid Archaeocete (Cetacea, Pelagiceti) From The Late Eocene Of Oregon, Usa, Mark D. Uhen, David Taylor Jan 2020

A Basilosaurid Archaeocete (Cetacea, Pelagiceti) From The Late Eocene Of Oregon, Usa, Mark D. Uhen, David Taylor

Geology Faculty Publications and Presentations

Background: Basilosaurid archaeocetes are known from the Late Eocene of virtually all coastlines bearing coeval marine rocks except the North Pacific Basin, until now. Here we report on three consecutive posterior thoracic vertebrae of a large, basilosaurid archaeocete from a Late Eocene horizon in the Keasey Formation in Oregon.

Methods: These vertebrae were morphologically and morphometrically compared to other vertebrae of similar age from around the world.

Results: The specimens were determined to be different from all currently named species of fossil cetacean, but most similar to those found in the Gulf Coast region of North America. …


The Role Of Warm, Dry Summers And Variation In Snowpack On Phytoplankton Dynamics In Mountain Lakes, Isabella A. Olesky, Whitney S. Beck, Roderick W. Lammers, Cara E. Steger, Codie Wilson, Kyle R. Christianson, Kim Vincent, Gunnar Forrest Johnson, Pieter T.J. Johnson, Jill S. Baron Jan 2020

The Role Of Warm, Dry Summers And Variation In Snowpack On Phytoplankton Dynamics In Mountain Lakes, Isabella A. Olesky, Whitney S. Beck, Roderick W. Lammers, Cara E. Steger, Codie Wilson, Kyle R. Christianson, Kim Vincent, Gunnar Forrest Johnson, Pieter T.J. Johnson, Jill S. Baron

Geology Faculty Publications and Presentations

Climate change is altering biogeochemical, metabolic, and ecological functions in lakes across the globe. Historically, mountain lakes in temperate regions have been unproductive because of brief ice-free seasons, a snowmelt-driven hydrograph, cold temperatures, and steep topography with low vegetation and soil cover. We tested the relative importance of winter and summer weather, watershed characteristics, and water chemistry as drivers of phytoplankton dynamics. Using boosted regression tree models for 28 mountain lakes in Colorado, we examined regional, intraseasonal, and interannual drivers of variability in chlorophyll a as a proxy for lake phytoplankton. Phytoplankton biomass was inversely related to the maximum snow …


A Primer On Laplacian Dynamics In Directed Graphs, J. J. P. Veerman, R. Lyons Jan 2020

A Primer On Laplacian Dynamics In Directed Graphs, J. J. P. Veerman, R. Lyons

Mathematics and Statistics Faculty Publications and Presentations

We analyze the asymptotic behavior of general first order Laplacian processes on digraphs. The most important ones of these are diffusion and consensus with both continuous and discrete time. We treat diffusion and consensus as dual processes. This is the first complete exposition of this material in a single work.


Storm Tide Amplification And Habitat Changes Due To Urbanization Of A Lagoonal Estuary, Philip Orton, Eric W. Sanderson, Stefan Talke, Mario Giampieri, Kytt Macmanus Jan 2020

Storm Tide Amplification And Habitat Changes Due To Urbanization Of A Lagoonal Estuary, Philip Orton, Eric W. Sanderson, Stefan Talke, Mario Giampieri, Kytt Macmanus

Civil and Environmental Engineering Faculty Publications and Presentations

In recent centuries, human activities have greatly modified the geomorphology of coastal regions. However, studies of historical and possible future changes in coastal flood extremes typically ignore the influence of geomorphic change. Here, we quantify the influence of 20th-century man-made changes to Jamaica Bay, New York City, on present-day storm tides. We develop and validate a hydrodynamic model for the 1870s based on detailed maps of bathymetry, seabed characteristics, topography, and tide observations for use alongside a present-day model. Predominantly through dredging, landfill, and inlet stabilization, the average water depth of the bay increased from 1.7 to 4.5 m, tidal …


Numerical Results For Adaptive (Negative Norm) Constrained First Order System Least Squares Formulations, Andreas Schafelner, Panayot S. Vassilevski Jan 2020

Numerical Results For Adaptive (Negative Norm) Constrained First Order System Least Squares Formulations, Andreas Schafelner, Panayot S. Vassilevski

Mathematics and Statistics Faculty Publications and Presentations

We perform a follow-up computational study of the recently proposed space–time first order system least squares ( FOSLS ) method subject to constraints referred to as CFOSLS where we now combine it with the new capability we have developed, namely, parallel adaptive mesh refinement (AMR) in 4D. The AMR is needed to alleviate the high memory demand in the combined space time domain and also allows general (4D) meshes that better follow the physics in space–time. With an extensive set of computational experiments, performed in parallel, we demonstrate the feasibility of the combined space–time AMR approach in both two space …


Strategies For Urban Pollinator Management Using Habitat Monitoring And Restoration Planning In Portland Oregon, Fiona Smeaton Jan 2020

Strategies For Urban Pollinator Management Using Habitat Monitoring And Restoration Planning In Portland Oregon, Fiona Smeaton

Environmental Science and Management Professional Master's Project Reports

Loss of habitat is a major factor in the decline of insect pollinators. Much of this loss can be attributed to monoculture farming, which is prevalent in Oregon. Depending on the crop, this approach to agriculture can create food deserts for native pollinators and presents dangerous exposures to pesticides. The resulting loss of habitat creates an opportunity for research on urban pollinator restoration. Many untapped land sources in urban environments may be improved to support a diverse abundance of pollinators. In this case study I wanted to understand what native bees and other insect pollinators could be observed at varied …


Collecting Plant Phenology Data In Imperiled Oregon White Oak Ecosystems: Analysis And Recommendations For Metro, Kirsten Wright Jan 2020

Collecting Plant Phenology Data In Imperiled Oregon White Oak Ecosystems: Analysis And Recommendations For Metro, Kirsten Wright

Environmental Science and Management Professional Master's Project Reports

Imperiled Oregon white oak ecosystems are a regional conservation priority due to the rich biodiversity they support, including rare and endemic species such as Oregon state-listed endangered pale larkspur (Delphinium leucophaeum). Previously dominant in the Pacific Northwest, upland prairie and oak woodlands are now under significant threat, with only 2% remaining in the Willamette Valley in small fragments.

Over the past 150 years, conversion to agriculture, urban development and fire suppression have dramatically reduced and degraded Oregon white oak habitat. Climate change has now emerged as an additional threat, causing observable shifts in plant phenology. In fragile oak …


Characterization Of Retinol Stabilized In Phosphatidylcholine Vesicles With And Without Antioxidants, Yekaterina G. Chmykh, Jay Nadeau Jan 2020

Characterization Of Retinol Stabilized In Phosphatidylcholine Vesicles With And Without Antioxidants, Yekaterina G. Chmykh, Jay Nadeau

Physics Faculty Publications and Presentations

Retinol stability has been reported to be improved by encapsulation in liposomes, both with and without cholesterol. However, this improvement is limited because of lipid peroxidation. In this study, we compare the stability of retinol in phosphatidylcholine liposomes under ultraviolet (UV) light or standard room air, with and without the addition of antioxidants. Both butylated hydroxytoluene (BHT) and a proprietary mix (StoppOx) improved the shelf stability from vesicles, including within the aqueous layer. Fluorescence lifetimes were equally heterogeneous. Under UV irradiation, StoppOx protected retinol for significantly longer than BHT and via different mechanisms. This suggests that natural antioxidants work well …


Membraneless H2o2 Fuel Cells Driven By Metallophthalocyanine Electrocatalysts, Bao Nguyen, Neal Kuperman, Gary Goncher, Raj Solanski Jan 2020

Membraneless H2o2 Fuel Cells Driven By Metallophthalocyanine Electrocatalysts, Bao Nguyen, Neal Kuperman, Gary Goncher, Raj Solanski

Physics Faculty Publications and Presentations

One-compartment hydrogen peroxide fuel cells with Co, Cu, and Fe phthalocyanine (PC) and iron nitride (FexN) as cathodes and Ni anode have been investigated as sustainable energy sources. The cells were operated under acidic conditions and at room temperature. The potentials for onset of the catalytic currents in these cells were determined via cyclic voltammograms. The reduction current onset potentials of FePC, CoPC, CuPC and FexN were 0.56 V, 0.42 V, 0.51 V and 0.57 V, respectively. Potentialcurrent linear sweep voltammetry was utilized to determine the open circuit potentials (OCP) and the power densities the fuel cells. The OCPs for …


Enhancing Final Image Contrast In Off-Axis Digital Holography Using Residual Fringes, Manuel Bedrossian, Kent Wallace, Eugene Serabyn, Chris Lindensmith, Jay Nadeau Jan 2020

Enhancing Final Image Contrast In Off-Axis Digital Holography Using Residual Fringes, Manuel Bedrossian, Kent Wallace, Eugene Serabyn, Chris Lindensmith, Jay Nadeau

Physics Faculty Publications and Presentations

We show that background fringe-pattern subtraction is a useful technique for removing static noise from off-axis holographic reconstructions and can enhance image contrast in volumetric reconstructions by an order of magnitude in the case for instruments with relatively stable fringes. We demonstrate the fundamental principle of this technique and introduce some practical considerations that must be made when implementing this scheme, such as quantifying fringe stability. This work also shows an experimental verification of the background fringe subtraction scheme using various biological samples.


Onset And Cause Of Increased Seismic Activity Near Pecos, West Texas, United States, From Observations At The Lajitas Txar Seismic Array, Clive Frohlich, Chris Hayward, Julia Rosenblit, Chastity Aiken, Peter Henning, Alexandros Savvaidis, Casee Lemons, Elizabeth Horne, Multiple Additional Authors Jan 2020

Onset And Cause Of Increased Seismic Activity Near Pecos, West Texas, United States, From Observations At The Lajitas Txar Seismic Array, Clive Frohlich, Chris Hayward, Julia Rosenblit, Chastity Aiken, Peter Henning, Alexandros Savvaidis, Casee Lemons, Elizabeth Horne, Multiple Additional Authors

Geology Faculty Publications and Presentations

In recent years, numerous small earthquakes have occurred near the town of Pecos in West Texas; however, when this activity began and whether it was caused by increased petroleum industry activity has been uncertain because prior to 2017 there were few permanent seismograph stations in the region. We identify and locate earthquakes using data recorded since 2000 at TXAR, a sensitive 10‐station seismic array situated about 240 km south of Pecos. We thus show that in 2007, one earthquake occurred near Pecos, in 2009 several more occurred, and subsequently, activity has increased considerably, with more than 2000 events identified in …


Deuterium Excess And 17o-Excess Variability In Meteoric Water Across The Pacific Northwest, Usa, John Bershaw, Dougal Hansen, Andrew Schauer Jan 2020

Deuterium Excess And 17o-Excess Variability In Meteoric Water Across The Pacific Northwest, Usa, John Bershaw, Dougal Hansen, Andrew Schauer

Geology Faculty Publications and Presentations

High-precision triple oxygen isotope analysis of water has given rise to a novel second-order parameter, 17O-excess (often denoted as δ17O), which describes the deviation from a reference relationship between δ18O and δ17O. This tracer, like deuterium excess (d-excess), is affected by kinetic fractionation (diffusion) during phase changes within the hydrologic cycle. However, unlike d-excess, 17O-excess is present in paleowater proxy minerals and is not thought to vary significantly with temperature. This makes it a promising tool in paleoclimate research, particularly in relatively arid continental regions where traditional approaches have produced equivocal results. …


Predicted Responses Of Beaches, Bays, And Inner-Shelf Sand Supplies To Potential Sea Level Rise (0.5-1.0 M) In Three Small Littoral Subcells In The High-Wave-Energy Northern Oregon Coast, Usa, Curt D. Peterson, Debra Lee Doyle, Charles L. Rosenfeld, Kara E. P. Kingen Jan 2020

Predicted Responses Of Beaches, Bays, And Inner-Shelf Sand Supplies To Potential Sea Level Rise (0.5-1.0 M) In Three Small Littoral Subcells In The High-Wave-Energy Northern Oregon Coast, Usa, Curt D. Peterson, Debra Lee Doyle, Charles L. Rosenfeld, Kara E. P. Kingen

Geology Faculty Publications and Presentations

Three small subcells (Nehalem, Tillamook, and Netarts) totaling ~55 km shoreline length in the high-wave energy northern Oregon coast are evaluated for potential beach sand loss from sea level rise (SLR) of 0.5–1.0 m during the next century. The predicted erosion is based on beach sand displacement from the narrow beaches (average ~120 m width) to increased submarine accommodation spaces in the innermost-shelf (to 30 m water depth) and in the subcell estuaries (Tillamook Bay, Netarts Bay, and Nehalem Bay), following predicted near-future SLR. Beach sand sources from local rivers, paleo-shelf deposits, and/or sea cliff retreat are discriminated by distinctive …


Boron Trifluoride Etherate Promoted Microwave Assisted Synthesis Of Antimalarial Acridones, Papireddy Kancharla, Rozalia A. Dodean, Yuexin Li, Jane X. Kelly Jan 2020

Boron Trifluoride Etherate Promoted Microwave Assisted Synthesis Of Antimalarial Acridones, Papireddy Kancharla, Rozalia A. Dodean, Yuexin Li, Jane X. Kelly

Chemistry Faculty Publications and Presentations

A microwave-assisted, rapid and efficient method using boron trifluoride etherate (BF3.Et2O) for the synthesis of acridones, via an intramolecular acylation of N-phenylanthranilic acid derivatives, has been developed. The reaction proceeds under solvent-free conditions, tolerates a wide range of functional groups, and provides rapid access to a range of acridones in good to excellent yields. Several of the synthesized acridones exhibited potent antimalarial activities against CQ sensitive and multi-drug resistant (MDR) parasites.


A Simple Predictive Model For Estimating Relative E-Cigarette Toxic Carbonyl Levels, Shawna Vreeke, Xijing Zhu, Robert Strongin Jan 2020

A Simple Predictive Model For Estimating Relative E-Cigarette Toxic Carbonyl Levels, Shawna Vreeke, Xijing Zhu, Robert Strongin

Chemistry Faculty Publications and Presentations

E-cigarette devices are wide ranging, leading to significant differences in levels of toxic carbonyls in their respective aerosols. Power can be a useful method in predicting relative toxin concentrations within the same device, but does not correlate well to inter-device levels. Herein, we have developed a simple mathematical model utilizing parameters of an e-cigarette’s coil and wick in order to predict relative levels of e-liquid solvent degradation. Model 1, which is coil length/(wick surface area*wraps), performed in the moderate-to-substantial range as a predictive tool (R2 = 0.69). Twelve devices, spanning a range of coil and wick styles, were analyzed. Model …


Daily Stream Samples Reveal Highly Complex Pesticide Occurrence And Potential Toxicity To Aquatic Life, Julia E. Norman, Barbara J. Mahler, Lisa H. Nowell, Peter C. Van Metre, Mark W. Sandstrom, Mark A. Corbin, Yaorong Qian, James F. Pankow, Wentai Luo, Nicholas B. Fitzgerald, Multiple Additional Authors Jan 2020

Daily Stream Samples Reveal Highly Complex Pesticide Occurrence And Potential Toxicity To Aquatic Life, Julia E. Norman, Barbara J. Mahler, Lisa H. Nowell, Peter C. Van Metre, Mark W. Sandstrom, Mark A. Corbin, Yaorong Qian, James F. Pankow, Wentai Luo, Nicholas B. Fitzgerald, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

Transient, acutely toxic concentrations of pesticides in streams can go undetected by fixed-interval sampling programs. Here we compare temporal patterns in occurrence of current-use pesticides in daily composite samples to those in weekly composite and weekly discrete samples of surface water from 14 small stream sites. Samples were collected over 10–14 weeks at 7 stream sites in each of the Midwestern and Southeastern United States. Samples were analyzed for over 200 pesticides and degradates by direct aqueous injection liquid chromatography with tandem mass spectrometry. Nearly 2 and 3 times as many unique pesticides were detected in daily samples as in …


Assessment Of Multi-Stressors On Compositional Turnover Of Diatom, Invertebrate And Fish Assemblages Along An Urban Gradient In Pacific Northwest Streams (Usa), Ian Waite, Yangdong Pan, Patrick M. Edwards Jan 2020

Assessment Of Multi-Stressors On Compositional Turnover Of Diatom, Invertebrate And Fish Assemblages Along An Urban Gradient In Pacific Northwest Streams (Usa), Ian Waite, Yangdong Pan, Patrick M. Edwards

Environmental Science and Management Faculty Publications and Presentations

This study is part of the regional stream-quality assessment (RSQA) conducted by the U.S. Geological Survey (USGS) National Water Quality Assessment (NAWQA) project. The purpose of this study is to examine small streams along land-use and stressor gradients at the regional scale and to evaluate the relative importance of instream stressors on diatom, macroinvertebrate, and fish assemblages. In 2015, the RSQA project assessed stream quality in 82 wadeable streams that were selected along an urban land-use gradient in the Pacific Northwest Region (PNW) of the United States. This study evaluates the effects of four major categories of measured instream stressors …


Microplastic Exposure By Razor Clam Recreational Harvester-Consumers Along A Sparsely Populated Coastline, Britta Baechler, Scott J. Mazzone, Elise F. Granek, Max Nielsen-Pincus, Susanne Brander Jan 2020

Microplastic Exposure By Razor Clam Recreational Harvester-Consumers Along A Sparsely Populated Coastline, Britta Baechler, Scott J. Mazzone, Elise F. Granek, Max Nielsen-Pincus, Susanne Brander

Environmental Science and Management Faculty Publications and Presentations

Microplastics (MPs) are anthropogenic contaminants found in coastal and marine environments worldwide. Pacific razor clams (Siliqua patula), important for local indigenous culture, economy, gastronomy and food security along the United States West Coast, are subjected to myriad environmental stressors including predation, storm events, disease, toxins, and MPs. This study aimed to determine MP burdens in Olympic Coast, Washington Pacific razor clams and estimate annual MP exposure of recreational razor clam harvester-consumers from eating this species. We quantified suspected MP burdens in Pacific razor clams collected from eight tribal, recreational, and commercial harvest areas on the Olympic Coast in April 2018. …


Chronic Chemogenetic Stimulation Of The Nucleus Accumbens Produces Lasting Reductions In Binge Drinking And Ameliorates Alcohol-Related Morphological And Transcriptional Changes, Dar'ya Y. Pozhidayeva, Sean Farris, Calla Goeke, Evan Firsick, Kayla G. Townsley, Marina Guizzetti, Angela Ozburn Jan 2020

Chronic Chemogenetic Stimulation Of The Nucleus Accumbens Produces Lasting Reductions In Binge Drinking And Ameliorates Alcohol-Related Morphological And Transcriptional Changes, Dar'ya Y. Pozhidayeva, Sean Farris, Calla Goeke, Evan Firsick, Kayla G. Townsley, Marina Guizzetti, Angela Ozburn

Chemistry Faculty Publications and Presentations

Binge drinking is a dangerous pattern of behavior. We tested whether chronically manipulating nucleus accumbens (NAc) activity (via clozapine-N-oxide (CNO) and Designer Receptors Exclusively Activated by Designer Drugs (DREADD)) could produce lasting eects on ethanol binge-like drinking in mice selectively bred to drink to intoxication. We found chronically increasing NAc activity (4 weeks, via CNO and the excitatory DREADD, hM3Dq) decreased binge-like drinking, but did not observe CNO-induced changes in drinking with the inhibitory DREADD, hM4Di. The CNO/hM3Dq-induced reduction in ethanol drinking persisted for at least one week, suggesting adaptive neuroplasticity via transcriptional and epigenetic mechanisms. Therefore, we defined this …