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Portland State University

Theses/Dissertations

2016

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Articles 31 - 60 of 64

Full-Text Articles in Physical Sciences and Mathematics

Assessment Of A Mycorrhizal Fungi Application To Treat Stormwater In An Urban Bioswale, Alaina Diane Melville Jul 2016

Assessment Of A Mycorrhizal Fungi Application To Treat Stormwater In An Urban Bioswale, Alaina Diane Melville

Dissertations and Theses

This study assessed the effect of an application of mycorrhizal fungi to stormwater filter media on urban bioswale soil and stormwater in an infiltration-based bioswale aged 20 years with established vegetation. The study tested the use of commercially available general purpose biotic soil blend PermaMatrix® BSP Foundation as a treatment to enhance Earthlite stormwater filter media amelioration of zinc, copper, and phosphorus in an ecologically engineered structure designed to collect and infiltrate urban stormwater runoff before it entered the nearby Willamette River.

These results show that the application of PermaMatrix® BSP Foundation biotic soil amendment to Earthlite …


Clear Creek Estuary Restoration: Establishing An Ecological Monitoring Program And Baseline Conditions, Christine Butler-Minor Jul 2016

Clear Creek Estuary Restoration: Establishing An Ecological Monitoring Program And Baseline Conditions, Christine Butler-Minor

Environmental Science and Management Professional Master's Project Reports

Monitoring habitat conditions in the Clear Creek Estuary before the completion of the Bucklin Hill Bridge Project is a critical part of this ecosystem restoration planning and execution. The Clear Creek Trail Alliance (CCTA) is working with local partners to monitor the effects of the estuary restoration. In a wider effort to characterize salmonid habitat suitability of the estuary prior to the bridge replacement, CCTA would like to gather data related to water quality, beach/bank elevations, vegetation in the vicinity, and invertebrate diversity in the estuary. The development and implementation of this Clear Creek Estuary monitoring project provides an opportunity …


Biomimetic Tools In Oxidative Metabolism: Characterization Of Reactive Metabolites From Antithyroid Drugs, Kudzanai Chipiso Jun 2016

Biomimetic Tools In Oxidative Metabolism: Characterization Of Reactive Metabolites From Antithyroid Drugs, Kudzanai Chipiso

Dissertations and Theses

Toxicities of sulfur-based drugs have been attributed to formation of highly reactive sulfur oxo-acids and depletion of glutathione by the formation of reactive metabolites. Metabolic activation of these sulfur centers to conceivably toxic reactive metabolites (RMs) that can covalently modify proteins is considered the initial step in drug-induced toxicity. Despite considerable effort and research, detection and characterization of these RMs during drug development and therapy remains a challenge. Methimazole (MMI) and 6-propyl-2-thiouracil (PTU) are two commonly used antithyroid, sulfur-based drugs. Though effective, these drugs are associated with idiosyncratic toxicity. PTU has acquired a black box warning and physicians are calling …


Connecting To Nature, Community, And Self: A Conservation Corps Approach To Re-Engaging At-Risk Youth In Science Education, Sara Jo Linden Jun 2016

Connecting To Nature, Community, And Self: A Conservation Corps Approach To Re-Engaging At-Risk Youth In Science Education, Sara Jo Linden

Dissertations and Theses

The social and environmental challenges of the coming decades will require that individuals possess environmental literacy: the understanding of natural systems combined with a sense of care for the earth, and the confidence and competency to act on its behalf. At the same time, disengaged youth need education environments that foster belonging and promote affective outcomes. The youth conservation corps model provides a natural context for engaging academically at-risk youth in environmental science education, while fostering connection to nature and student self-efficacy in ways that are experiential, relevant, and relationship-based. The focus of this study was a conservation corps program …


Large Length Scale Capillary Fluidics: From Jumping Bubbles To Drinking In Space, Andrew Paul Wollman Jun 2016

Large Length Scale Capillary Fluidics: From Jumping Bubbles To Drinking In Space, Andrew Paul Wollman

Dissertations and Theses

In orbit, finding the "bottom" of your coffee cup is a non-trivial task. Subtle forces often masked by gravity influence the containment and transport of fluids aboard spacecraft, often in surprising non-intuitive ways. Terrestrial experience with capillary forces is typically relegated to the micro-scale, but engineering community exposure to large length scale capillary fluidics critical to spacecraft fluid management design is low indeed. Low-cost drop towers and fast-to-flight International Space Station (ISS) experiments are increasing designer exposure to this fresh field of study. This work first provides a wide variety of drop tower tests that demonstrate fundamental and applied capillary …


Investigating The Potential Of Land Use Modifications To Mitigate The Respiratory Health Impacts Of No2: A Case Study In The Portland-Vancouver Metropolitan Area, Meenakshi Rao Jun 2016

Investigating The Potential Of Land Use Modifications To Mitigate The Respiratory Health Impacts Of No2: A Case Study In The Portland-Vancouver Metropolitan Area, Meenakshi Rao

Dissertations and Theses

The health impacts of urban air pollution are a growing concern in our rapidly urbanizing world. Urban air pollutants show high intra-urban spatial variability linked to urban land use and land cover (LULC). This correlation of air pollutants with LULC is widely recognized; LULC data is an integral input into a wide range of models, especially land use regression models developed by epidemiologists to study the impact of air pollution on human health. Given the demonstrated links between LULC and urban air pollution, and between urban air pollution and health, an interesting question arises: what is the potential of LULC …


The Terroir Of Pinot Noir Wine In The Willamette Valley, Oregon : A Broad Analysis Of Vineyard Soils, Grape Juice And Wine Chemistry, Kathryn Nora Barnard Jun 2016

The Terroir Of Pinot Noir Wine In The Willamette Valley, Oregon : A Broad Analysis Of Vineyard Soils, Grape Juice And Wine Chemistry, Kathryn Nora Barnard

Dissertations and Theses

Terroir is determined by a combination of factors in the vineyard including the grape varietal, geology and soil, soil hydrology, physiography, and climate. Although most studies have examined regional differences in wine flavors and associated provenance of wine based on chemistry, few have examined the chemistry of the soil and the ability to trace that chemistry to grape juice and, finally, to the wine. This dissertation examines what soil physical and chemical differences specific to this region might influence grape juice chemistry and wine chemistry.

Wine-grapes in the Willamette Valley, Oregon, are grown on three major soil parent materials: volcanic, …


Photoemission Electron Microscopy For Analysis Of Dielectric Structures And The Goos-Hänchen Shift, Theodore Axel Stenmark Jun 2016

Photoemission Electron Microscopy For Analysis Of Dielectric Structures And The Goos-Hänchen Shift, Theodore Axel Stenmark

Dissertations and Theses

Photoemission Electron Microscopy (PEEM) is a versatile tool that relies on the photoelectric effect to produce high-resolution electron images. Ultrafast pulse lasers allow for multi-photon PEEM where multiple visible or IR photons excite a single electron in a nonlinear process. The photoelectron yield in both cases is related to the near-field region of electromagnetic fields at the surface of the sample. We use this ability here to analyze wave propagation in a linear dielectric waveguide with wavelengths of 410 nm and 780 nm. The propagation constant of the waveguide can be extracted from interference patterns created by light propagating in …


Relationships That Extend Beyond The Fence-Line: Private Landowner Attitudes And Interest In Conservation Easements, Ashley Lyn Vizek May 2016

Relationships That Extend Beyond The Fence-Line: Private Landowner Attitudes And Interest In Conservation Easements, Ashley Lyn Vizek

Dissertations and Theses

Private land conservation provides an opportunity to address problems of habitat fragmentation and biodiversity loss caused by an increase in the development and parcelization of private land. Conservation easements (CEs) are an innovative tool used by land trusts to protect significant natural qualities of private land in perpetuity, while also allowing the land to remain in private ownership. Traditionally, property represents an individualistic relationship, however, CEs redefine this relationship by seeking to maximize the overlap in private and public goods in property. In this study, I explore the relationship between the common good and private property through an analysis of …


Factors Driving The Concentration Of Ephemeral Flow, Gretchen Anne Guyer May 2016

Factors Driving The Concentration Of Ephemeral Flow, Gretchen Anne Guyer

Dissertations and Theses

In spite of decades of related research, stream channel initiation is still not well understood. Current theories of channel initiation are grounded in research conducted by Montgomery and Dietrich, largely in the transport limited, temperate, humid climate of the Pacific Northwest, USA. This field data driven work concluded that the drainage area required for channel initiation is directly correlated to the slope of the contributing area. However, there are a host of related variables that have yet to be examined in the field. This study revisits the slope-area relationship focusing on ephemeral overland flow in headwaters of both the Pacific …


The Effects Of Phosphonic Acids In Dye-Sensitized Solar Cells, Keith Edward James May 2016

The Effects Of Phosphonic Acids In Dye-Sensitized Solar Cells, Keith Edward James

Dissertations and Theses

Novel methods for the construction of dye-sensitized solar cells (DSSCs) were developed. A thin dense underlayer of TiO2 was applied on fluorine-doped tin oxide (FTO) glass using as a precursor Tyzor AA-105. Subsequently a mesoporous film of P-25 TiO2 was applied by spreading a suspension uniformly over the surface of the underlayer and allowing the plate to slowly dry while resting on a level surface. After sintering at 500° C slides were treated with TCPP as a sensitizing dye and assembled into DSSCs. A novel method was used to seal the cells; strips of Parafilm® were used as …


Green Roofs And Urban Biodiversity: Their Role As Invertebrate Habitat And The Effect Of Design On Beetle Community, Sydney Marie Gonsalves May 2016

Green Roofs And Urban Biodiversity: Their Role As Invertebrate Habitat And The Effect Of Design On Beetle Community, Sydney Marie Gonsalves

Dissertations and Theses

With over half the world's population now living in cities, urban areas represent one of earth's few ecosystems that are increasing in extent, and are sites of altered biogeochemical cycles, habitat fragmentation, and changes in biodiversity. However, urban green spaces, including green roofs, can also provide important pools of biodiversity and contribute to regional gamma diversity, while novel species assemblages can enhance some ecosystem services. Green roofs may also mitigate species loss in urban areas and have been shown to support a surprising diversity of invertebrates, including rare and endangered species. In the first part of this study I reviewed …


An Investigation Of Invasion: Boater Knowledge Concerning Aquatic Invasive Species And The Influence Of The New Zealand Mud Snail On Benthic Food Webs, Samuel Anthony Cimino May 2016

An Investigation Of Invasion: Boater Knowledge Concerning Aquatic Invasive Species And The Influence Of The New Zealand Mud Snail On Benthic Food Webs, Samuel Anthony Cimino

Dissertations and Theses

Invasive species are second only to habitat loss as a leading cause of native species displacement and the management of invasive species costs hundreds of billions annually. Invasion is often conceptualized as a series of stages (Transport, Introduction, Establishment, and Spread), which encourages ecologists to isolate factors that might enable a species to pass from one stage to another and therefore guide prevention or impact management. This thesis addresses each stage of invasion and attempts to determine where management might succeed in preventing invasion or minimizing impacts. The transport and introduction of aquatic invasive species (AIS) was analyzed by conducting …


Accuracy Of Wave Speeds Computed From The Dpg And Hdg Methods For Electromagnetic And Acoustic Waves, Nicole Michelle Olivares May 2016

Accuracy Of Wave Speeds Computed From The Dpg And Hdg Methods For Electromagnetic And Acoustic Waves, Nicole Michelle Olivares

Dissertations and Theses

We study two finite element methods for solving time-harmonic electromagnetic and acoustic problems: the discontinuous Petrov-Galerkin (DPG) method and the hybrid discontinuous Galerkin (HDG) method.

The DPG method for the Helmholtz equation is studied using a test space normed by a modified graph norm. The modification scales one of the terms in the graph norm by an arbitrary positive scaling parameter. We find that, as the parameter approaches zero, better results are obtained, under some circumstances. A dispersion analysis on the multiple interacting stencils that form the DPG method shows that the discrete wavenumbers of the method are complex, explaining …


Physics-Based Imaging Methods For Terahertz Nondestructive Evaluation Applications, Gabriel Paul Kniffin May 2016

Physics-Based Imaging Methods For Terahertz Nondestructive Evaluation Applications, Gabriel Paul Kniffin

Dissertations and Theses

Lying between the microwave and far infrared (IR) regions, the "terahertz gap" is a relatively unexplored frequency band in the electromagnetic spectrum that exhibits a unique combination of properties from its neighbors. Like in IR, many materials have characteristic absorption spectra in the terahertz (THz) band, facilitating the spectroscopic "fingerprinting" of compounds such as drugs and explosives. In addition, non-polar dielectric materials such as clothing, paper, and plastic are transparent to THz, just as they are to microwaves and millimeter waves. These factors, combined with sub-millimeter wavelengths and non-ionizing energy levels, makes sensing in the THz band uniquely suited for …


Investigations Of An "Objectness" Measure For Object Localization, Lewis Richard James Coates May 2016

Investigations Of An "Objectness" Measure For Object Localization, Lewis Richard James Coates

Dissertations and Theses

Object localization is the task of locating objects in an image, typically by finding bounding boxes that isolate those objects. Identifying objects in images that have not had regions of interest labeled by humans often requires object localization to be performed first. The sliding window method is a common naïve approach, wherein the image is covered with bounding boxes of different sizes that form windows in the image. An object classifier is then run on each of these windows to determine if each given window contains a given object. However, because object classification algorithms tend to be computationally expensive, it …


On The Variability Of Pacific Ocean Tides At Seasonal To Decadal Time Scales: Observed Vs Modelled, Adam Thomas Devlin May 2016

On The Variability Of Pacific Ocean Tides At Seasonal To Decadal Time Scales: Observed Vs Modelled, Adam Thomas Devlin

Dissertations and Theses

Ocean tides worldwide have exhibited secular changes in the past century, simultaneous with a global secular rise in mean sea level (MSL). The combination of these two factors contributes to higher water levels, and may increase threats to coastal regions and populations over the next century. Equally as important as these long-term changes are the short-term fluctuations in sea levels and tidal properties. These fluctuations may interact to yield locally extreme water level events, especially when combined with storm surge. This study, presented in three parts, examines the relationships between tidal anomalies and MSL anomalies on yearly and monthly timescales, …


Tree Graphs And Orthogonal Spanning Tree Decompositions, James Raymond Mahoney May 2016

Tree Graphs And Orthogonal Spanning Tree Decompositions, James Raymond Mahoney

Dissertations and Theses

Given a graph G, we construct T(G), called the tree graph of G. The vertices of T(G) are the spanning trees of G, with edges between vertices when their respective spanning trees differ only by a single edge. In this paper we detail many new results concerning tree graphs, involving topics such as clique decomposition, planarity, and automorphism groups. We also investigate and present a number of new results on orthogonal tree decompositions of complete graphs.


Introducing Complex Systems Analysis In High School Mathematics Using System Dynamics Modeling: A Potential Game-Changer For Mathematics Instruction, Diana Marie Fisher May 2016

Introducing Complex Systems Analysis In High School Mathematics Using System Dynamics Modeling: A Potential Game-Changer For Mathematics Instruction, Diana Marie Fisher

Dissertations and Theses

Complex systems abound on this planet, in the composition of the human body, in ecosystems, in social interaction, in political decision-making, and more. Analytical methods allowing us to better understand how these systems operate and, consequently, to have a chance to intervene and change the undesirable behavior of some of the more pernicious systems have developed and continue to be enhanced via quickly changing technology. Some of these analytical methods are accessible by pre-college students, but have not been widely used at that level of education. Jay Forrester, the founder of one of the methodologies, System Dynamics (SD), used to …


The Foundations Of Network Dynamics In An Rna Recombinase System, Jessica Anne Mellor Yeates May 2016

The Foundations Of Network Dynamics In An Rna Recombinase System, Jessica Anne Mellor Yeates

Dissertations and Theses

How life originated from physical and chemical processes is one of the great questions still unanswered today. Studies towards this effort have transitioned from the notion of a single self-replicating entity to the idea that a network of interacting molecules made this initial biological leap. In order to understand the chemical kinetic and thermodynamic mechanisms that could engender pre-life type networks we present an empirical characterization of a network of RNA recombinase molecules. We begin with 1-, 2-, and 3-molecular ensembles and provide a game theoretic analysis to describe the frequency dependent dynamics of competing and cooperating RNA genotypes. This …


Discrete Stability Of Dpg Methods, Ammar Harb May 2016

Discrete Stability Of Dpg Methods, Ammar Harb

Dissertations and Theses

This dissertation presents a duality theorem of the Aubin-Nitsche type for discontinuous Petrov Galerkin (DPG) methods. This explains the numerically observed higher convergence rates in weaker norms. Considering the specific example of the mild-weak (or primal) DPG method for the Laplace equation, two further results are obtained. First, for triangular meshes, the DPG method continues to be solvable even when the test space degree is reduced, provided it is odd. Second, a non-conforming method of analysis is developed to explain the numerically observed convergence rates for a test space of reduced degree. Finally, for rectangular meshes, the test space is …


Identifying Relationships Between Scientific Datasets, Abdussalam Alawini May 2016

Identifying Relationships Between Scientific Datasets, Abdussalam Alawini

Dissertations and Theses

Scientific datasets associated with a research project can proliferate over time as a result of activities such as sharing datasets among collaborators, extending existing datasets with new measurements, and extracting subsets of data for analysis. As such datasets begin to accumulate, it becomes increasingly difficult for a scientist to keep track of their derivation history, which complicates data sharing, provenance tracking, and scientific reproducibility. Understanding what relationships exist between datasets can help scientists recall their original derivation history. For instance, if dataset A is contained in dataset B, then the connection between A and B could be that A was …


A Chemistry Neutral Flow Battery Performance Model Development, Validation, And Application, Alasdair James Crawford Apr 2016

A Chemistry Neutral Flow Battery Performance Model Development, Validation, And Application, Alasdair James Crawford

Dissertations and Theses

A physical model for redox flow batteries is developed to estimate performance for any chemistry using parameters such as electrolyte conductivity and kinetic rate constants. The model returns the performance as a function of flow rate, current density, and state of charge. Two different models are developed to estimate the current density distribution throughout the electrode in order to evaluate physical performance of the battery. This is done using electrochemical parameters such as conductivity and kinetic rate constant. The models are analytical in order to produce a computationally cheap algorithm that can be used in optimization routines. This allows for …


Arsenic Mobilization From Silicic Volcanic Rocks In The Southern Willamette Valley, Gabriela Ribeiro De Sena Ferreira Mar 2016

Arsenic Mobilization From Silicic Volcanic Rocks In The Southern Willamette Valley, Gabriela Ribeiro De Sena Ferreira

Dissertations and Theses

Volcanic tuffs and tuffaceous sediments are frequently associated with elevated As groundwater concentrations even though their bulk As contents (~ 5 mg kg-1; Savoie, 2013) are only marginally greater than the average crustal abundance of 4.8 mg g-1 (Rudnick & Gao, 2003). Thus, As mobilization must be facilitated by conditions particular to these rocks. Alkaline desorption, anionic competition, reactive glass dissolution, and reductive dissolution of iron oxides are proposed processes of As release from volcanic rocks. Geogenic As contamination of groundwater in the southern Willamette Valley in western Oregon has been well-documented since the early 1960s, and …


Pharmaceutical Contaminants As Stressors On Rocky Intertidal And Estuarine Organisms: A Case Study Of Fluoxetine, Joseph Richard Peters Mar 2016

Pharmaceutical Contaminants As Stressors On Rocky Intertidal And Estuarine Organisms: A Case Study Of Fluoxetine, Joseph Richard Peters

Dissertations and Theses

Contaminants such as pharmaceuticals are of increasing concern due to their ubiquitous use and persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals on marine life, despite widespread detection of these contaminants in the marine environment. Of the existing studies, the majority assess the negative effects of pharmaceuticals over an exposure period of 30 days or less and focus on cellular and subcellular biomarkers. Longer studies are required to determine if chronic contaminant exposure poses risks to marine life at environmentally relevant concentrations. Also scarce in the literature is examination of whole organism effects …


Field Geology And Petrologic Investigation Of The Strawberry Volcanics, Northeast Oregon, Arron Richard Steiner Feb 2016

Field Geology And Petrologic Investigation Of The Strawberry Volcanics, Northeast Oregon, Arron Richard Steiner

Dissertations and Theses

The Strawberry Volcanics of Northeast Oregon are a group of geochemically related lavas with a diverse chemical range (basalt to rhyolite) that erupted between 16.2 and 12.5 Ma and co-erupted with the large, (~200,000 km3) Middle Miocene tholeiitic lavas of the Columbia River Basalt Group (CRBG), which erupted near and geographically surround the Strawberry Volcanics. The rhyolitic lavas of the Strawberry Volcanics produced the oldest 40Ar/39Ar ages measured in this study with ages ranging from 16.2 Ma to 14.6 Ma, and have an estimated total erupted volume of 100 km3. The mafic and intermediate lavas of the Strawberry Volcanics include …


One-Dimensional Nanostructure And Sensing Applications: Tin Dioxide Nanowires And Carbon Nanotubes, Hoang Anh Tran Feb 2016

One-Dimensional Nanostructure And Sensing Applications: Tin Dioxide Nanowires And Carbon Nanotubes, Hoang Anh Tran

Dissertations and Theses

The key challenge for a nanomaterial based sensor is how to synthesize in bulk quantity and fabricate an actual device with insightful understanding of operational mechanisms during performance. I report here effective, controllable methods that exploit the concepts of the "green approach" to synthesize two different one-dimensional nanostructures, including tin oxide nanowires and carbon nanotubes. The syntheses are followed by product characterization and sensing device fabrications as well as sensor performance understanding at the molecular level. Sensor-analyte response and recovery kinetics are also presented.

The first part of the thesis describes bulk-scale synthesis and characterization of tin oxide nanowires by …


Slope Failure Detection Through Multi-Temporal Lidar Data And Geotechnical Soils Analysis Of The Deep-Seated Madrone Landslide, Coast Range, Oregon, Michael Scott Marshall Jan 2016

Slope Failure Detection Through Multi-Temporal Lidar Data And Geotechnical Soils Analysis Of The Deep-Seated Madrone Landslide, Coast Range, Oregon, Michael Scott Marshall

Dissertations and Theses

Landslide hazard assessment of densely forested, remote, and difficult to access areas can be rapidly accomplished with airborne light detection and ranging (lidar) data. An evaluation of geomorphic change by lidar-derived digital elevation models (DEMs) coupled with geotechnical soils analysis, aerial photographs, ground measurements, precipitation data, and numerical modeling can provide valuable insight to the reactivation process of unstable landslides. A landslide was selected based on previous work by Mickleson (2011) and Burns et al. (2010) that identified the Madrone Landslide with significant volumetric changes. This study expands on previous work though an evaluation of the timing and causation of …


Greenroof Study: Final Report, An Assessment Of Greenroof Design And Maintenance In Portland, Oregon: 2011 – 2013, Windy Carney Beck Jan 2016

Greenroof Study: Final Report, An Assessment Of Greenroof Design And Maintenance In Portland, Oregon: 2011 – 2013, Windy Carney Beck

Environmental Science and Management Professional Master's Project Reports

In 1999 the City of Portland (City) began to require that stormwater management facilities (SMF) be built when private property is newly developed or redeveloped (City Code Chapter 17.38). Proper maintenance and upkeep of SMFs is essential to ensuring they function appropriately. The City's Maintenance Inspection Program (MIP) is tasked with inspecting stormwater management facilities on private properties in order to ensure that they are being properly operated and maintained and to meet provisions of the City's NPDES Municipal Separated Storm Sewer System (MS4) permit.

Greenroofs are one type of SMF that are installed to satisfy this requirement. Understanding the …


Assessment Of Tmdl Implementation And Water Quality Status And Trends In Amazon Creek And Coyote Creek Watersheds, Stosh Zydek Jan 2016

Assessment Of Tmdl Implementation And Water Quality Status And Trends In Amazon Creek And Coyote Creek Watersheds, Stosh Zydek

Environmental Science and Management Professional Master's Project Reports

In this project, I analyzed the status and trends of water quality data describing fecal bacteria (E. coli) and DO in the Amazon and Coyote Creek watersheds of the Southern Willamette Valley, Oregon. I also examined TMDL implementation plans produced by DMAs, determined if and how implementation activities corresponded to changes in water quality, compared management and planning of DMAs in the watersheds, discussed aspects of the current TMDL, and compared state regulations and standards in other states. I concluded by making management recommendations to better facilitate future status and trend analysis.

Amazon Creek, Amazon Diversion Channel, A-3 …