Physical Sciences and Mathematics Commons^™

Toward Accurate And Efficient Computational Screening Of The Electronic Structure And Band Gaps Of Semiconductors, Linda Grabill

WWU Graduate School Collection

With increasing population, growing energy demands, and environmental concerns the search for greener energy resources has intensified in recent decades. For example, in the ongoing effort to harness solar energy, researchers have worked to identify and optimize the efficiency of semiconductors beyond traditional silicon photovoltaic materials.

In the development of new materials, synthetic chemists and materials scientists often look to computational chemistry to guide and understand experiments. In the case of semiconductors for solar energy conversion, this includes calculations of electronic band structure and band gap. The most precise computational approaches, such as density functional theory (DFT) are both time …

Teaching Environmental/Stem College Access Curriculum In Two Western Washington Title I Elementary Schools, Wendelin Dunlap

WWU Graduate School Collection

This study attempts to answer the question: What are the best methods for designing Environmental/STEM College Access Curriculum for Title I Classrooms? Participants were 98 5^th-grade classes at two Title I schools. The treatment was 15 hours of College Access Curriculum: 7 hours occurred at the North Cascades Institute’s Mountain School, eight hours in the students’ regular classrooms. The curriculum was taught by Western Washington University students trained as coaches. Data were gathered from elementary students (pre- and post-program surveys, retrospective questionnaire and open-ended question), coaches (essays and teacher evaluations) and teachers (feedback form).

Data gathered from elementary …

Development Of A Samarium Based Allylic Benzoate Elimination/Isomerization: Application To A Total Synthesis Of Honokiol, Alicia M. Wright

WWU Graduate School Collection

We have developed a new samarium diiodide-mediated elimination/isomerization reaction of benzoyl esters, capable of delivering olefinic products with high yield and selectivity depending on substrate structure and the additives used. The ability to selectively synthesize terminal, non-conjugated alkene substituents inspired us to use these optimized conditions in order to complete the total synthesis of the natural product, honokiol. Honokiol is a biaryl natural product isolated from magnolia trees that displays desirable oncological properties as evidenced by several biological studies in recent years. We found that our initially proposed pathway for completing the synthesis of honokiol was not a feasible route …

Wisdom Of The Ancient Forests: Stories In The Living Thread, Nick Sky

WWU Graduate School Collection

In this project I am using my life experiences as an evolving environmental educator to create a theoretical and content base for an educational approach that combines holistic natural history education and complexity education. This approach is necessarily transdisciplinary. This educational approach is designed to be implemented using methods that are field based, inquiry based, narrative based, and learning communities based. The implementation of this educational approach is designed to take place in the ancient forests of the Cascadia/PNW region of North America.

Key Words: Complexity, Experiential education, Ancient forest, Resilience, Holistic, Emotion, Natural history, Perception, Time, Values

The Deoxygenation And Hydrogenation Properties Of Noble Metal-Based Bimetallic Phosphide Catalysts, Paul M. Cochran

WWU Graduate School Collection

With increasing concern regarding the environmental impacts of fossil fuels, and the difficulty of extracting petroleum feedstocks, alternative liquid fuels are becoming more desirable. Bio-oil, which is oil derived from biomass, is a renewable source of liquid fuels. However, the high oxygen and water content of bio-oil results in high corrosivity and low energy density, making it unusable in the current liquid fuel infrastructure. The process of removing heteroatom impurities from oil is known as hydrotreating. Current hydrotreating catalysts are optimized for refinement of petroleum, and are not suitable for bio-oil deoxygenation. Transition metal phosphides (such as Ru₂P) …

Copper Indium Disulfide Nanocrystal Luminescent Solar Concentrators, Ryan I. (Ryan Isaac) Sumner

WWU Graduate School Collection

The sun is the most prominent renewable energy resource. Technologies such as photovoltaics (PVs) have yet to emerge as a cost effective alternative to non-renewable energy resources such as fossil fuels. Luminescent solar concentrators (LSC) possess the ability to lower the cost of solar energy by the reduction of the photovoltaic cell area and yet increase photovoltaic conversion efficiency. LSC’s offer an attractive approach to concentrating both specular and diffuse light, which eliminates expensive solar tracking methods. Luminophores for LSC applications are often dominated by reabsorption losses and absorb a small part of the solar spectrum, which prevents LSC’s from …

Spatial Variability Of Snow Chemistry Of High Altitude Glaciers In The Peruvian Andes, Lindsay K. Wallis

WWU Graduate School Collection

Atmospheric contaminants become incorporated in glaciers through both wet and dry deposition. Some of this particulate matter can act as a source of contamination to glacial streams, leading to a concern for the chemical contamination to cause downstream toxicity to aquatic organisms and toxicity to people ingesting that water. Other portions of this particulate matter, including black carbon, can decrease the amount of light reflected off the snow, thereby contributing to increased rates of glacial melting. These issues are especially of concern to tropical glaciers, which are receding rapidly and are relied on heavily to provide drinking water in the …

Modeling The Effects Of Forecasted Climate Change And Glacier Recession On Late Summer Streamflow In The Upper Nooksack River Basin, Ryan D. Murphy

WWU Graduate School Collection

Like many watersheds in the North Cascades range of Washington State, USA, streamflow in the Nooksack River is strongly influenced by precipitation and snowmelt in the spring and glacial ice melt in the warmer summer months. With a maritime climate and high relief containing approximately 34km² of glacial ice, the streamflow response in the Nooksack River basin is sensitive to increases in temperature. Climate projections from global climate models (GCMs) for the 21st Century indicate increases in temperature with variable changes to precipitation. The watershed is a valuable freshwater resource for regional municipalities, industry, and agriculture, and provides critical …

Black Cottonwood (Populus Trichocarpa) Nutrition In The Dewatered Lake Aldwell Reservoir On The Elwha River, Washington, Ezra H. Citron

WWU Graduate School Collection

Following dam removal on the Elwha River, WA, the ability of plants to access and uptake nutrients may be an important factor in ecosystem recovery. Foliage was collected in November 2014 from naturally-established black cottonwood (Populus trichocarpa) saplings growing in the dewatered Lake Aldwell reservoir sediments and adjacent forest. Analysis of variance was used to assess variability among reservoir sediment textures and the adjacent forest with respect to foliar macronutrient (N, P, K, Ca, Mg) and micronutrient (Fe, Mn, Zn, Cu, Ni) concentrations. Within the reservoir, foliar P, K, and Mn were higher, and foliar Ca was lower, …

Progress Toward Structural Studies Of A Circularly Permuted Human Hemoglobins Containing T-State Stabilizing Mutations, Rachel J. (Rachel Joy) Hubbard

WWU Graduate School Collection

Our research is focused on the production of a hemoglobin based oxygen carrier (HBOC) which can be used as a therapeutic in the event of acute blood loss. The administration of cell-free hemoglobin is associated with severe adverse effects due to dissociation of the tetrameric α₂β₂ complex into αβ heterodimers. Our approach to the design of an effective HBOC, is based on a recombinant circularly permuted human hemoglobin in which all of the subunits are linked in a single-chain fashion. This design would prevent the dissociation of the tetramer and allow for the biosynthesis of polymeric hemoglobins of defined mass. …

Water Quality And Algal Diversity Of Ten Lakes Along The Mountain Loop Highway, Washington, Katy Pfannenstein

WWU Graduate School Collection

Water quality parameters, watershed characteristics and algal diversity and abundance were compared in ten lakes along the Mountain Loop Highway in Washington State. Water samples were collected in July and August 2014 and analyzed for temperature, dissolved oxygen, alkalinity, conductivity, pH, turbidity, chlorophyll, total phosphorous, total nitrogen, soluble reactive phosphorous, nitrate + nitrite, silica, chloride, sulfate, total organic carbon, dissolved organic carbon and total and dissolved metals (aluminum, antimony, arsenic, barium, beryllium, cadmium, calcium, chromium, cobalt, copper, iron, lead, magnesium, manganese, molybdenum, nickel, potassium, selenium, silver, sodium, thallium, thorium, uranium, vanadium and zinc). The watershed characteristics measured were elevation, lake …

Ring-Closing Metathesis Reactions Of Acyloxysulfones: Synthesis Of Γ-Alkylidene Butenolides, Iris T. Phan

WWU Graduate School Collection

As we set out to investigate ring-closing methatesis reactions of acyloxysulfones, we discovered that treatment with triethylamine resulted in its quantitative conversion into the γ-alkylidene butenolides. γ-Alkylidene Butenolides are common to a number of biologically important natural products, and have been of great interest. To date, there has been no metathesis-based synthesis of γ-alkylidene butenolides making our approach the first. Development of the metathesis-based approach has allowed us to synthesize a variety of γ-alkylidene butenolides from the RCM products in high yields (69-100%). The elimination is proposed to proceed via an E1cb mechanism leading to (Z)-γ-alkylidene butenolides as …

Creating A Community Hub For Natural History Education In The Methow Valley And Beyond, Mary Kiesau

WWU Graduate School Collection

I created and integrated three different methods of natural history education for my final project of my Masters of Education in Environmental Education in order to further establish myself as a professional educator, communicator and naturalist, and to create ways for people who live in or have an affinity for the Methow Valley to be more observant, informed and connected with the natural world. Building on previous graduate coursework as well as professional work as an environmental educator and photographer, I created a new natural history education website and Facebook page with a wide variety of online resources, while also …

Synthesis & Reactivity Of Iron (Ii) Pyridinediimine Complexes For The Reduction Of Nitrite, Yubin Kwon

WWU Graduate School Collection

The activation of small molecules has been studied by the scientific field for many decades as it plays a key role in nature such as photosynthesis and respiration. Many of these reactions are catalyzed by metalloenzymes in nature where the transfer of electrons and protons are coupled for the reaction to move forward. Noncovalent interactions in the secondary coordination sphere of metalloenzymes play an important role in determining the activity and selectivity. Hydrogen bonds are the most common noncovalent interactions that metalloenzymes utilize to control the reactivity in the secondary coordination sphere. Therefore, it is important to develop compounds and …

Mineral Complexities As Evidence For Open-System Processes In Formation Of Intermediate Magmas Of The Mount Baker Volcanic Field, Northern Cascade Arc, Ricardo D. (Ricardo Daniel) Escobar-Burciaga

WWU Graduate School Collection

To better understand the complex history of open system differentiation in intermediate subduction zone magmas, complex crystal populations from andesites in the Mount Baker volcanic field (MBVF) in the northern Cascade arc were analyzed. Previous studies have suggested that open-system processes play a dominant role in the petrogenesis of these andesites; however, the studies relied heavily on bulk rock compositions and overlooked complex mineral textures and compositions. This study focuses on establishing mineral and crystal clot populations in four andesite flow units, from which co-crystallizing assemblages were identified. The flow units are the medium-K andesites of Swift Creek (asw …

Microzooplankton Grazing, Growth And Gross Growth Efficiency Are Affected By Pco2 Induced Changes In Phytoplankton Biology, Kelly Still

WWU Graduate School Collection

Accumulating evidence shows that ocean acidification (OA) alters surface ocean chemistry and, in turn, affects aspects of phytoplankton biology. However, very little research has been done to determine if OA-induced changes to phytoplankton morphology, physiology and biochemistry may indirectly affect microzooplankton, the primary consumers of phytoplankton. This is one of the first studies to explore how OA may indirectly affect microzooplankton ingestion, population growth and gross growth efficiency (GGE). I hypothesized 1) that the physiology, biochemistry and morphology of the phytoplankton Rhodomonas sp. would be directly affected by elevated pCO₂ and 2) that pCO₂-induced changes in Rhodomonas …

Fine-Scale Topoclimate Modeling And Climatic Treeline Prediction Of Great Basin Bristlecone Pine (Pinus Longaeva) In The American Southwest, Jamis M. Bruening

WWU Graduate School Collection

Great Basin bristlecone pine (Pinus longaeva) and foxtail pine (Pinus balfouriana) are valuable paleoclimate resources due to the climatic sensitivity of their annually-resolved rings. Recent treeline research has shown that growing season temperatures limit tree growth at and just below the upper treeline. In the Great Basin, the presence of precisely dated remnant wood above modern treeline shows that this ecotone shifts at centennial timescales tracking long-term changes in climate; in some areas during the Holocene climatic optimum treeline was 100 meters higher than at present. Such phenomena has motivated this analysis; regional treeline position models built exclusively from climate …

Development Of 2d And 3d Conductive Biomaterial Composites For Use As Electromechanical Actuators, Sean Severt

WWU Graduate School Collection

Flexible and conductive biocompatible materials are attractive candidates for a wide range of biomedical applications including implantable electrodes, tissue engineering, and controlled drug delivery. Here we demonstrated that chemical and electrochemical polymerization techniques can be combined to create highly versatile silk-conducting polymer (silk-CP) composites with enhanced conductivity and electrochemical stability. Interpenetrating silk-CP composites were first generated via in situ deposition of polypyrrole during chemical polymerization of pyrrole. These composites were sufficiently conductive to serve as working electrodes for electropolymerization, allowing an additional layer of CP to be deposited on the surface. This two-step technique expanded the range of available polymers …

Cluster Analysis As A Means Of Examining Topographically-Mediated Bristlecone Pine (Pinus Longaeva) Growth In The American Southwest, Tyler J. Tran

WWU Graduate School Collection

Tree-ring analysis can provide information about the surrounding environment of trees, as ring widths often reflect the variability of the factors that limit their growth. Great Basin bristlecone pine (Pinus longaeva D. K. Bailey) provides crucial tree-ring data to understand paleoclimate, but the growth signals can be difficult to interpret. The bristle- cone record could present a potentially confounding narrative because of its mixed growth signals; in many cases, not all trees at one site are limited by the same environmental variable. Trees that are sensitive to patterns in temperature tend to grow in the alpine upper treeline ecotone, and …

Emergent Contaminants And Effects On Field-Exposed Chinook Salmon And Cutthroat Trout In The Stillaguamish Watershed, Wa., Jody M. Pope

WWU Graduate School Collection

Contaminants of emerging concern (CECs) are chemical compounds that have no regulatory standards, are recently discovered in the natural environment due to improved analytical methods, and can potentially cause adverse effects to aquatic life. More specifically, CECs affecting fish communities include endocrine disrupting chemicals (EDCs), which can produce developmental abnormalities or alter the epigenome, potentially affecting survival and reproductive success. This study assessed CEC occurrence as well as toxicological and epigenetic responses of caged, hatchery-reared Chinook salmon (Oncorhynchus tshawytscha) and field-collected, wild, resident cutthroat trout (O. clarkii) at sites representing different land uses in the Stillaguamish River watershed, …

Exploring The Biofuel Potential Of Isochrysis Sp., John R. Williams Ii

WWU Graduate School Collection

A select few strains of marine microalgae, such as Isochrysis sp., produce high-melting (∼70 °C) lipids known as long-chain alkenones that detrimentally affect biodiesel fuel quality. A method has been developed for the production of an alkenone-free Isochrysis biodiesel. This material was prepared on sufficient scale to allow for extensive analysis according to ASTM standards. Results revealed that while cold flow improved by removal of these high-melting components, a cloud point was still unattainable due to the fuels dark pigment. Further effort in relating the presence of alkenones and the resulting cloud point of the biodiesel, led to decolorization of …

A Dynamic Bayesian Approach For Integrating Climate Change Into A Multi-Stressor Ecological Risk Assessment For The Mercury Contaminated South River And Upper Shenandoah River, Lara Gaasland-Tatro

WWU Graduate School Collection

Anthropogenic climate change is causing the earth to warm, and the consequences of warming will be on a continuum for species from extinction to thriving and expanding to larger ranges. There will be winners with climate change and there will be losers, and identifying species that management would benefit early makes management more effective. Environmental factors and contaminants complicate species responses to climate change. Sites with legacy contaminants, like mercury, that stay in the environment for extended periods will need to be managed for the mixed effects of climate change, environmental stressors and contaminants. In this study I use an …

Predicting Risk To Estuary Water Quality And Patterns Of Benthic Environmental Dna In Queensland, Australia Using Bayesian Networks, Scarlett E. Graham

WWU Graduate School Collection

Predictive modeling can inform natural resource management by demonstrating stressor-response pathways and quantifying the effects on selected endpoints. This study develops a risk assessment model using the Bayesian network-relative risk model (BN-RRM) approach, and, for the first time, incorporates eukaryote environmental DNA data as a measure of benthic community structure into an ecological risk assessment context. Environmental DNA sampling is a relatively new technique for biodiversity measurements that involves extracting DNA from environmental samples, sequencing a region of the 18s rDNA gene, and matching the sequences to organisms. Using a network of probability distributions, the BN-RRM model predicts risk to …

A Holocene Glaciolacustrine Record Of The Lyman Glacier And Implications For Glacier Fluctuations In The North Cascades, Washington, Harold N. Wershow

WWU Graduate School Collection

The Holocene glacial history of the North Cascades is poorly understood, in part because most existing records rely on moraine remnants and are therefore discontinuous. To develop a more complete record of Holocene fluctuations of North Cascades glaciers, we collected and analyzed glaciolacustrine sediments (i.e., rock flour) deposited over the past ~7800 years in Lyman Lake by the upstream Lyman Glacier. We combined these results with equilibrium-line altitude (ELA) reconstructions and glacier-climate modeling to quantify the climatic conditions that drove these fluctuations. Finally, we compared the Lyman Glacier’s continuous fluctuation record to existing glacier and climate records of the North …

Mechanisms Of Inverted Seismic Multiplets, Joel Brann

WWU Graduate School Collection

In seismology, multiplets are a series of earthquakes with similar waveforms that are thought to represent a repeating process occurring at the same location. A few studies have previously identified multiplets with waveforms that are inverted relative to one another; here termed inverted multiplets (IMs).For this study, several data sets were searched for additional examples of IMs, including earthquake swarms associated with a volcanic eruption (Mt. Spurr), a dike intrusion (Nechako Basin), dome building (Mt. St. Helens), and times of no volcanic or magmatic activity (Piton de la Fournaise [PDLF], Mt. Spurr). Source mechanisms are determined to describe what could …

Mapping Interactions Between The Type-Vi Secretion System Effector Tae1 And Its Putative Substrates Using Nmr Spectroscopy, Robert C. (Robert Corey) Henderson

WWU Graduate School Collection

Tae1 is an amidase produced by gram negative Pseudomonas bacteria that attacks the peptidoglycan layer in the cell walls of neighboring bacteria after secretion through the Type VI secretion system (T6S). The goal of our work is mapping interactions between the type-VI-secretion system effector Tae1 and its putative substrates using nuclear magnetic resonance (NMR) spectroscopy. Tae1 is amenable to NMR in that we are able to collect spectra with resolved, well defined peaks that can be assigned, thereby providing valuable structural information. We have assigned 89.2% of backbone atoms and 87.4% of sidechain atoms. Assignment of Tae1 was performed with …

Comprehensive Solution Structure Analysis Of Dna Duplexes Containing Chemical Base Alterations, Joanna Hoppins

WWU Graduate School Collection

Most types of chemical modifications of DNA bases are endogenous processes which are sensitive to the intracellular conditions. For example, the enzymatically catalyzed methylation of canonical cytosine to 5-methylcytosine (5metC) is a key form of epigenetic regulation of gene expression patterns. This modification is catalyzed and controlled by DNA methyltransferases (DNMTs). Perturbed rates of enzymatic DNA methylation leads to hyper- or hypo-methylation, both of which are a common initiating step in several forms of cancer. In addition to epigenetics, DNA bases can be chemically altered, or damaged, in response to reactive oxygen species (ROS). The oxidation of DNA by ROS …

The Effect Of High-Intensity Visible Light On The Bloom Niches Of The Phototrophic Dinoflagellates Alexandrium Fundyense And Heterocapsa Rotundata, Elizabeth C. (Elizabeth Colleen) Cooney

WWU Graduate School Collection

Photosynthetic bloom-forming dinoflagellates heavily influence coastal ecosystems worldwide. Many of these protist algae bloom in surface waters during summer when light intensities are highest. Despite its likely role as a top-down regulator of bloom formation, the consequences of high-intensity sunlight exposure on cells are not well understood. This study sought to reveal the effect of high light exposure on cells, keeping in mind the potential consequences for bloom-formation. The suite of conditions under which a species is best adapted to bloom is referred to here as its “bloom niche”. To investigate, I measured physiological changes deemed relevant to bloom health …

Fluvial Incision, Upper Plate Faulting, And Short-Term Deformation In The Southern Olympic Mountains Of Washington State, Jaime Delano

WWU Graduate School Collection

Understanding topographic development in subduction zone forearcs requires comparison of deformation at short and long-term time intervals. We focus here on geomorphic records of uplift and incision in the Cascadia forearc of Washington State for comparison with short-term deformation driven by subduction zone coupling. We use surficial geologic mapping, optically stimulated luminescence dating, and surveyed terrace strath elevations to document fluvial incision and fault slip rates in the Wynoochee River valley in the southern Olympic Mountains. Results from 14 optically stimulated luminescence samples yield fluvial terrace age groupings of ~7-12 ka, ~14-18 ka, ~30-45 ka, and ~50-60 ka, which likely …

Seagrasses (Zostera Marina) And (Zostera Japonica) Display A Differential Photosynthetic Response To Tco2: Implications For Acidification Mitigation, Cale A. Miller

WWU Graduate School Collection

Excess atmospheric CO₂ is being absorbed at an unprecedented rate by the global and coastal oceans, shifting the baseline pCO₂ and altering seawater carbonate chemistry in a process known as ocean acidification (OA). Recent attention has been given to near-shore vegetated habitats, such as seagrass beds, which may have the potential to mitigate the effects of acidification on vulnerable calcifying organisms via photosynthesis. Seagrasses are capable of raising seawater pH and calcium carbonate saturation state during times of high photosynthetic activity. To better understand the photosynthetic potential of seagrass OA mitigation, we exposed Pacific Northwest populations of …