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The Cognition Of Controversy: Examining Policy Elites’ Narrative Cognition And Communication Around Hydraulic Fracturing Practices In The U.S., Rachael M. Moyer

Graduate Theses and Dissertations

The use of hydraulic fracturing (HF) technologies to extract oil and gas in the United States has sparked contentious policy debates, producing inconsistent and inefficient policies that have done little to address the impacts of HF in any comprehensive way. Debates are accompanied by competing policy narratives that position HF as either an environmental threat or an economic opportunity, but little is known about how policy narratives around HF are used by individuals. This dissertation systematically examines how individuals cognitively internalize elements of competing HF policy narratives. Organized into three empirical chapters, this dissertation analyzes narrative cognition (Jones, Shanahan, and …

Arboretum Exchange, Fall 2019, Olivia Arias, Zinan Chi, Rudy Lawler, Emily Nelson, Ryan Rhee

Sustainability Exchange Projects

The Arboretum Project, led by Professor Stan Braude of Biology, worked to certify the WashU campus as a Level II Arboretum. Students learned to identify and catalog trees, identified creative ways to engage the public with WU campus natural resources, and worked with Buildings & Grounds and the Office of Sustainability to plan for the future of tree initiatives on campus.

Sustainable Flowers, Fall 2019, Rose Ho, Annie Yaris, Maia Sanders, Sophie Watterson

Sustainability Exchange Projects

The Sustainable Flowers Initiative, led by Professor Suzanne Langlois of Arts & Sciences, aimed to shift the supply chain of floral arrangements on campus from depending upon resource-intensive, chemical-heavy international suppliers. Students developed a strategy for working collaboratively with campus event organizers, local floral suppliers, and WU Grounds & Maintenance to make floral arrangements more sustainable.

Biochar As A Means Of Water Purification In Haiti, Caolan Keenan

Honors Projects

Our research set out to determine if biochar, a compound made by burning organic plant matter in a low oxygen environment, would be a suitable means of removing E. coli populations from contaminated water collected from the Grand River in Allendale, MI using simple materials to construct a filter that could be constructed and used in Haiti. Previous research has shown biochar to be effective at trapping bacteria and other contaminants in the porous surface and by binding other non organic contaminants. We constructed multiple iterations of these filters using gravel, sand, and biochar and ran three live tests with …

Correlating Census Data With Boces Enrollment Demographics: A Study On The Need For Demographic Cohesion, Dana N. Roman

Career & Technical Education Theses

BOCES was a public institution originally created in 1948 to enable smaller rural school districts to combine resources and funding. Pooling of resources allows for the creation of programs that would not otherwise be economically feasible due to low population density and funding gaps (boces.org). BOCES has evolved to include rural and larger school districts as well. Just as there is a need for the skills learned at BOCES to match industry demands, so too is there a need for the work-force diversity to be reflected in the student population at BOCES. To meet this need, BOCES administration must pay …

Bitcoin Price Prediction Using Neural Networks, Vladislav Killiakov

Electrical Engineering

In this project, I will investigate the performance of several major neural network architectures for the task of Bitcoin price prediction. Bitcoin is a cryptocurrency that is recently becoming increasingly more popular, and more widely adopted as a financial instrument. As a result, more efforts have been made in the past several years to model and predict its price. However, to this moment a large portion of work on Bitcoin price modeling was done using statistical or classical machine learning techniques. At the same time, other artificial intelligence based prediction techniques, and specifically neural networks, have not been explored to …

Student Perception Data And Its Impact On Teachers, Erica R. Walker-Arnold

Department of Educational Administration: Dissertations, Theses, and Student Research

For as long as there have been teachers, there have been efforts to determine the most constructive way to evaluate teacher effectiveness. Research has shown that traditional administrator evaluations do little to improve struggling teachers and that most teachers nationwide are able to earn satisfactory ratings even when they are not performing in a satisfactory manner. This study aims to determine whether using student perception feedback as part of a comprehensive teacher evaluation process would lead to improved practice and targeted professional development. The following questions were investigated in this research: 1. Does student perception feedback drive teachers to reflect …

Towards The Synthesis Of An Artificial Fluorescent Siderophore, Ashley Burns

Honors Theses

Siderophores are molecules capable of binding ferric ions with high affinity (Ka = 1052). This thesis outlines our attempts to synthesize an artificial siderophore, which incorporates a signaling group to help monitor the uptake of ferric ions. The artificial siderophore is a tripodal molecular receptor synthesized in a five-step procedure with a proposed final sixth step. Rhodamine 6G azide (95.0% yield) was formed from rhodamine 6G and the synthesis of 2-azidoethanamine was modified from the literature. The tripodal arm portion of the sensor was successfully synthesized by protecting the catechol of 2,3-dihydroxybenzaldehyde to form 3-formyl-1,2-phenylene dimethanesulfonate (98.8% yield). The reduction …

Lattice Thermal Conductivity Of Quartz At High Pressure And Temperature From The Boltzmann Transport Equation, Xue Xiong, Eugene J. Ragasa, Aleksandr V. Chernatynskiy, Dawei Tang, Simon R. Phillpot

Physics Faculty Research & Creative Works

The thermal conductivities along the basal and hexagonal directions of α-quartz silica, the low-temperature form of crystalline SiO₂, are predicted from the solution of the Boltzmann transport equation combined with the van Beest, Kramer, and van Santen potential for the temperature up to 900 K and the pressure as high as 4 GPa. The thermal conductivities at atmospheric pressure, which show a negative and nonlinear dependence on temperature, are in reasonable agreement with the experimental data. The influence of pressure on thermal conductivity is positive and linear. The pressure (P) and temperature (T) dependences of the thermal conductivity …

Radio Direction Finding Using Pseudo-Doppler For Uav-Based Animal Tracking, Anup Karki

Masters Theses

Radio Direction Finding (RDF) is commonly used for low cost tracking and navigation systems. However, for a low cost application and mobility, the design constraints are highly limited. Pseudo Doppler (PD) can improve RDF capabilities without being cost prohibitive. This work entails the analysis of PD RDF and its potential use for Unmanned Aerial Vehicles (UAV) that are currently employed in wildlife research animal tracking. PD is based on the doppler effect or doppler shift. The doppler effect works like a frequency modulator that increases or decreases the observed frequency depending on whether a signal source is approaching or receding …

Characterizing Hydrothermal System Groundwater Dynamics Using Conservative And Non-Conservative Tracers: Insights And Implications Drawn From Study At The Taupo Volcanic Zone (New Zealand) And Valles Caldera (Usa), Joshua Michael Blackstock

Graduate Theses and Dissertations

Hydrothermal systems constitute an important component of heat and mass transport within Earth’s crust having direct and indirect impacts to society. Investigating contemporary hydrochemical differences and change are critical to evaluating and deconvolving factors that influence geothermal systems through time. In this dissertation, groundwater mixing approaches were used to study hydrochemical differences in two globally significant hydrothermal areas, which included fabrication of a low-cost dissolved CO2 monitoring for dissolved inorganic carbon (DIC). In the Taupo Volcanic Zone (New Zealand), empirical spatial relations were used to derive low-temperature groundwater end-members of Cl and Cl/Br for end-member mixing analysis (EMMA). Using EMMA, …

The Feedback-Related Negativity Is A Time-Dependent Brain Mechanism That Facilitates Aversive Learning: Implications For The Reinforcement Learning Frn Hypothesis, Eric Rawls

Graduate Theses and Dissertations

Organisms encode rewarding and aversive experiences through reinforcement learning, capitalizing on prediction errors (PEs), which adapt action strategies over time. Computational theories are explicit that PE signals should update action weights continuously over the course of a behavioral task, an important time-dependent variation that is eschewed in traditional neuroscience studies that average over large numbers of trials. I examined variation in reaction times and feedback-locked cortical activity over time as a function of PE to critically examine theories indicating that PE signals drive time-dependent learning. We recorded EEG while participants completed a novel reinforcement task that varied prediction error on …

Interfacial Contact With Noble Metal - Noble Metal And Noble Metal - 2d Semiconductor Nanostructures Enhance Optical Activity, Ricardo Raphael Lopez Romo

Graduate Theses and Dissertations

Noble metal nanoparticles and two-dimensional (2D) transition metal dichalcogenide (TMD) crystals offer unique optical and electronic properties that include strong exciton binding, spin-orbital coupling, and localized surface plasmon resonance. Controlling these properties at high spatiotemporal resolution can support emerging optoelectronic coupling and enhanced optical features. Excitation dynamics of these optical properties on physicochemically bonded mono- and few-layer TMD crystals with metal nanocrystals and two overlapping spherical metal nanocrystals were examined by concurrently (i) DDA simulations and (ii) far-field optical transmission UV-vis spectroscopic measurements. Initially, a novel and scalable method to unsettle van der Waals bonds in bulk TMDs to prepare …

Understanding And Controlling Lithium Microstructure During Electroplating For Energy Applications, Yang Tian

Graduate Theses and Dissertations

Lithium-ion batteries are reaching the specific theoretical capacity limit, while lithium metal batteries are regarded as the ideal energy storage system for the next generation “beyond lithium-ion” battery systems. The lithium metal anode is considered as the “Holy grail” of anodes due to its relatively low electrochemical potential (-3.04 V vs SHE) and high theoretical capacity (3860 mAh g-1). However, the application of lithium metal anodes is hindered because of significant reaction between metallic lithium and electrolytes, as well as uneven electro-plating, which leads to dendrite formation, causing safety problems.

The kinetic parameters of Li ions such as diffusion coefficient …

Surface Modification Of Pvdf Membranes For Treating Produced Waters By Direct Contact Membrane Distillation, Zahra Anari

Graduate Theses and Dissertations

Direct contact membrane distillation is a promising unit operation for treating hydraulic fracturing flow back and produced water. However, while a hydrophobic membrane is essential to prevent the passage of water from the feed to the permeate side, fouling by dissolved organic species can compromise membrane performance and result in wetting of the membrane pores. Here four monomers, hydroxyethylmethacrylate, acrylic acid, 1-vinyl-3-allylimidazolium bromide, and 1-vinyl-3-hexylimidazolium bromide have been grafted from the surface of a PVDF membrane. The modified and base membranes were tested in a direct contact membrane distillation system. All membranes were challenged with real produced water. In addition, …

Fractional Order State Feedback Control For Improved Lateral Stability Of Semi-Autonomous Commercial Heavy Vehicles, Rasheed Mazen Abdulkader

Graduate Theses and Dissertations

With the growing development of autonomous and semi-autonomous large commercial heavy vehicles, the lateral stability control of articulated vehicles have caught the attention of researchers recently. Active vehicle front steering (AFS) can enhance the handling performance and stability of articulated vehicles for an emergency highway maneuver scenario. However, with large vehicles such tractor-trailers, the system becomes more complex to control and there is an increased occurrence of instabilities. This research investigates a new control scheme based on fractional calculus as a technique that ensures lateral stability of articulated large heavy vehicles during evasive highway maneuvering scenarios. The control method is …

Rotational Tuning Of Transmembrane Helix Properties Based On The Precise Placements Of Aromatic And Charged Residues, Matthew J. Mckay

Graduate Theses and Dissertations

Designed model transmembrane peptides and oriented 2H and 15N solid-state nuclear magnetic resonance (NMR) spectroscopy were used to analyze how simple sequence modifications can influence peptide structure, behavior and dynamics as well as for determining the pKa of glutamic acid at the membrane interface. The GW5,19ALP23 (acetyl-GGALW(LA)6LWLAGA-amide) peptide framework adopts a well-defined tilted orientation in lipid bilayers (DLPC, DMPC and DOPC) and undergoes low amounts of dynamic motion. The sequence was initially modified by moving the Trp residues outwards to positions 4 and 20. This new sequence GW4,20ALP23 (acetyl-GGAW(AL)7AWAGA-amide) displays high amounts of signal averaging of NMR observables caused by …

Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason

Graduate Theses and Dissertations

I investigated the lasting impacts of a management plan designed to improve oak regeneration and benefit wildlife in the Ozark Highlands in Madison, Co., AR. To assess the efficacy of the management plan, I used variables relevant to the success and establishment of oak trees. Controlled burns and selective logging were used to thin the canopy, increase ground level productivity, and increase the abundance of small mammals. I used measurements of overstory and understory densities, light availability, and the density of mice in the genus Peromyscus across time to look at the lasting impacts of management. Different treatment plots were …

Probing Of Carbohydrate-Protein Interactions Using Galactonoamidine Inhibitors, Jessica B. Pickens

Graduate Theses and Dissertations

Glycoside hydrolases are ubiquitous and one of the most catalytically proficient enzymes known, and thus understanding their mechanisms are crucial. Most research has focused on the interaction of the glycon of substrates and their inhibitors within the active site of glycoside hydrolases. The inhibitors employed to probe these interactions generally had small aglycons (i.e. a hydrogen atom, amidines, small aliphatic groups, or benzyl groups). Here, the interactions of the aglycon with glycoside hydrolases are examined by probing the active sites with a library of 25 galactonoamidines. The studies described in this dissertation aim to increase the understanding of stabilization of …

Nematode Populations As Affected By Residue And Water Management In A Long-Term Wheat-Soybean Double Crop In Eastern Arkansas, Lucia Emperatriz Escalante Ortiz

Graduate Theses and Dissertations

Soybeans (Glycine max) are one of the major row crops in the United States, particularly in Arkansas. Soybean cyst nematode (SCN, Heterodera glycines) and southern root-knot nematode (RKN, Meloidogyne incognita) are two of the most damaging pests that cause major economic losses in soybeans. Little is known concerning the effects of common and alternative agronomic practices on nematodes in fields with nematode population densities below threshold levels. Therefore, the objective of this study was to evaluate the effects of the combination of tillage (conventional tillage and no-tillage), irrigation (irrigated and non-irrigated), wheat (Triticum aestivum) residue burning (burned and no burned), …

An Investigation Of Metal Sulfides As The Source Of The Low Emissivity Anomaly On The Highlands Of Venus, Sara Taeko Port

Graduate Theses and Dissertations

Since its detection in the 1960s the source of the unusual radar emissivity signal seen on several highlands on Venus has long eluded researchers. Researchers have determined that a mineral with a high dielectric constant could explain the signal. Using a Venus simulation chamber, we experimentally investigated this enigma to build upon the candidate mineral list that has been compiled over the last several decades. We tested the stability of 8 different minerals and elements at two to three different temperature/pressure regimes in three different gas mixtures meant to simulate the conditions found on Venus for a period of no …

Studies Of Initial Growth Of Gan On Inn, Alaa Alnami

Graduate Theses and Dissertations

III-nitride materials have recently attracted much attention for applications in both the microelectronics and optoelectronics. For optoelectronic devices, III-nitride materials with tunable energy band gaps can be used as the active region of devices to enhance the absorption or emission. A such material is indium nitride (InN), which along with gallium nitride (GaN) and aluminum nitride (AlN) embody the very real promise of forming the basis of a broad spectrum, a high efficiency solar cell. One of the remaining complications in incorporating InN into a solar cell design is the effects of the high temperature growth of the GaN crystal …

Reactivity Of Photogenerated Amine Radical Cations, Qile Wang

Graduate Theses and Dissertations

Recently photoredox catalysis has emerged as a powerful tool in organic synthesis led by Professor McMillan, Stephenson, Yoon. Upon absorption of visible light, photocatalyst can be excited to its singlet state followed by intersystem crossing to form a long lived excited triplet state. While amine serves as electron donor, single electron transfer (SET) can happen between excited triplet photocatalyst and nitrogen atom on amine to give a reduced photocatalyst and amine radical cation.

Cyclopropylamines or cyclobutylamines can be oxidized by excited photocatalyst to generate amine radical cations and due to the ring strain, subsequent C-C bond cleavages can lead to …

Suitability Assessment For Integrated Urban Development In Makkah City Of Saudi Arabia, Mislat Alotaibi

Graduate Theses and Dissertations

Makkah – the third most populated city in Saudi Arabia with a population of 1,684,408 according to the 2010 demographic survey conducted by the Saudi General Authority for Statistics – is experiencing urban sprawl, which can be defined as an unplanned urban expansion that might degrade the environment and diminish the aesthetic view. This is a persisting problem in Makkah driven by multitude of processes involving the random expansion in its undeveloped land and the removal of its historic mountains surrounding Al-Masjid Al-Haram (the Holy Mosque) in an attempt to push the city limit of urban capacity within its administrative …

Improving Earthquake Disaster Models With Post-Event Data: Insights From The 2015 Gorkha, Nepal Earthquake, Bradley Steven Wilson

Graduate Theses and Dissertations

Immense amounts of data are collected following earthquake disasters. Yet, it remains unclear how researchers’ might take full advantage of diverse post-disaster datasets. Using data from the 2015 Gorkha Nepal earthquake, this dissertation explores three ways in which post- disaster survey and assessment datasets can be used to inform models of seismic risk, vulnerability, and recovery processes. The first article presents an empirical analysis of scale issues in disaster vulnerability indices using a novel dataset of 750,000 households. This study finds that using aggregated household data to create social vulnerability indices can produce results that are meaningfully different from equivalent …

The Shelf To Basin Transition And Tectonostratigraphy Of The Atoka Formation (Lower Pennsylvanian) In The Arkoma Basin, Northwest Arkansas, Travis Gibson White

Graduate Theses and Dissertations

The east-to-west oriented Arkoma Basin is a peripheral foreland basin or depositional trough that developed during the Carboniferous Period. This formation covers an aerial extent of approximately 33,800 square miles and spans from west-central Arkansas into southeastern Oklahoma (McGilvery, Manger, and Zachry, 2016; Perry, 1995). The Atoka Formation, deposited during the early Pennsylvanian, is the largest Paleozoic formation by aerial extent in the state of Arkansas and is located within and comprises the bulk of Arkoma Basin sediments (McFarland, 2004; Nance, 2018). This formation has been informally divided into three divisions, the lower, middle, and upper, based on their stratigraphic …

Quantitative Study Of The Antimicrobial Effects Of Silver On The Motility Of Escherichia Coli, Benjamin Russell

Graduate Theses and Dissertations

In recent decades, the number of antibiotic-resistant bacterial infections has grown to become a serious global threat. This rise can be attributed to the widespread misuse of antibiotics and the lack of newly developed drugs to fight resistant organisms. Novel bactericidal substances have, therefore, garnered significant research interest. Silver, due to its powerful antimicrobial effects, is one such substance. Silver is typically most effective in cationic form; however, advancements in nanotechnology have paved the way for the controlled fabrication of nano-silver. Silver nanoparticles have been shown to have increased antibacterial potency for a variety of reasons, including the release of …

The Van Hiele Analysis Of Curricular Materials: A Comparative Study, Vinay Kumar Kalyankar

Graduate Theses and Dissertations

The goal of this study is to investigate K-8 geometry curriculum standards and textbooks for their effectiveness in preparing students for high school geometry. The basis for the study is van Hiele theory pioneered by the Dutch educators and researchers of geometric understanding in adolescents, Dina van Hiele Geldof and Pierre van Hiele. Another driving force for this dissertation is research into mathematics textbooks and curriculum standards of school mathematics as seen in CCSSM and state specific standards documents, both of which influence the mathematics students have the opportunity to learn.

The K-8 geometry curriculum standards and textbook instructional segments …

Strategies To Improve Forage Utilization By Sheep Offered Forage Mixtures, Valens Niyigena

Graduate Theses and Dissertations

In the first experiment, alfalfa and novel endophyte-infected tall fescue (NE+) forages were harvested after a killing frost, then mixed to formulate 4 different treatments; alfalfa alone, 67% alfalfa +33% fescue, 33% alfalfa + 67% fescue, or 100% fescue. After 3 months of storage as silage, Dorper ewe lambs (n = 20; mean BW = 34.7 ± 6.65 kg) were fed silage for ad libitum consumption, using 5 animals per treatment. Increasing the proportion of NE+ tall fescue improved (P < 0.05) silage total acids and lactic acid concentrations and decreased silage ammonia concentration. Digestible dry matter and organic matter intake and nitrogen utilization parameters decreased with increasing inclusion of NE+ in diet. In the second experiment, 16 Dorper ewe lambs (41.8 ± 4.61 kg BW) were assigned to 4 different treatments; alfalfa silage alone (0 g/kg; CONT) or alfalfa silage mixed with chopped sericea lespedeza (SL) hay to provide 90 (LOW), 180 (MED), or 270 g/kg SL (HIGH) on a dry matter basis in a randomized complete block design experiment with 2 period to provide 4 observations per treatment for each experimental period. Increasing the proportion of sericea lespedeza in the diet decreased dry matter and organic matter digestibility but did not affect feed intake. Fecal nitrogen (g/kg N intake) increased linearly (P < 0.01) while urinary N (g/ day and g/ kg of N intake) tended to decreased linearly and quadratically (P ≤ 0.1) with increasing the proportion of SL in diet. In the third experiments, 16 gestating Dorper ewe lambs (49.1 ± 4.61 kg BW) were allocated to 4 treatments; alfalfa silage alone (0% g/kg; CONT) or alfalfa silage mixed with lablab purpureus(LP) hay to provide 90 (LOW), 180 (MED), or 270 g/kg LP (HIGH) on a dry matter (DM) basis, in a randomized complete block design experiment with a total 8 replication per treatment. Supplementation of LP in diet increased quadratically (P ≤ 0.04) forage dry matter, organic matter intake, digestible dry matter and digestible organic matter intake (P < 0.05). Nitrogen apparently absorbed and urinary N both decreased linearly (P < 0.01) with adding more LP hay in diet. Harvesting and mixing alfalfa and fescue after a killing frost improved silage fermentation characteristics and supplementation of tannins from SL and polyphenol from LP altered N excretion.

Key words: lablab, sericea lespedeza, alfalfa silage, nitrogen, sheep.

Contrasting Geometric Variations Of Mathematical Models Of Self-Assembling Systems, Michael Sharp

Graduate Theses and Dissertations

Self-assembly is the process by which complex systems are formed and behave due to the interactions of relatively simple units. In this thesis, we explore multiple augmentations of well known models of self-assembly to gain a better understanding of the roles that geometry and space play in their dynamics. We begin in the abstract Tile Assembly Model (aTAM) with some examples and a brief survey of previous results to provide a foundation. We then introduce the Geometric Thermodynamic Binding Network model, a model that focuses on the thermodynamic stability of its systems while utilizing geometrically rigid components (dissimilar to other …