Digital Commons Network^™

Thermal Alteration Of The Mineralogy Of Calcium Sulfoaluminate Cements: Implications For The Performance Of Rapid Repair Materials, Jillian Cavellier

Theses and Dissertations--Earth and Environmental Sciences

Calcium sulfoaluminate (CSA) was developed in part to lessen the environmental impact of cementitious materials compared to traditional Portland cements. CSA was first put into production in the 1970s and has been undergoing various performance testing to investigate its durability. Yet to be evaluated is CSA’s response to a rapid, high temperature event. In this study, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectrometry and scanning electron microscope imaging were used to analyze alterations in the mineralogy due to such an event. As found in previous studies, after ~125°C, ettringite has been completely dehydrated. Ettringite decomposes into bassanite and calcium …

Assessing Microplastic Contamination Within Karst Groundwater Basins In Kentucky, Maaz Fareedi

Theses and Dissertations--Earth and Environmental Sciences

The input and abrasion of plastic waste in the environment has long been known to form microplastics (MPs). These ubiquitous contaminants are easily mobilized into hydrologic systems. MPs are now being found in karst aquifers around the world, including several across Kentucky, USA. Due to their size (< 5 mm in diameter), chemical properties, abundance, and wide distribution, MPs pose numerous ecological hazards, including uptake by organisms and as substrates for contaminant sorption. Karst groundwater is especially vulnerable to surface contaminants; however, knowledge of the extent of karst MP contamination is limited, with most studies focused on individual sites or small areas. In this study, we created a MP contamination dataset for 30 karst springs and 10 locations where cave sediments were characterized across Kentucky. MP concentrations in groundwater samples ranged from 0 to 41.1 items/L and yielded an average of 4.9 ± 8.7 items/L. Sediment MP concentrations ranged from 0 to 306 items/kg. We performed statistical analyses and linear regressions to examine whether groundwater MP concentrations could be explained by factors including land use, population density, basin area, numbers of sinkholes, and sinking streams. Our models revealed that population density, agrarian land use, sinking stream density, and basin area were related to MP concentrations. All factors except basin area trended positively with MP concentration, while basin area trended negatively. These relations are generally corroborated by existing literature, however they indicate that further studies with considerably larger sample sizes are needed to determine mechanistic relationships.

Visualizing And Automating Past, Real-Time, And Forecast Dynamic Hazard Maps For Shallow Colluvial Landslides In Eastern Kentucky, Nathaniel O'Leary

Theses and Dissertations--Earth and Environmental Sciences

Landslide hazards are a persistent threat to communities and infrastructure in Eastern Kentucky, where steep slopes, shallow colluvial soils, and variable hydrological conditions make slope failures frequent. This thesis presents an integrated approach to landslide hazard mapping (LHM) through the development of dynamic, spatiotemporal LHMs for shallow colluvial landslides. Two studies within this work investigate and refine the use of the Lu and Godt (2008) factor of safety (FS) equation to improve landslide predictions. The first study establishes a novel LHM workflow using Hydrus-1D to simulate soil moisture infiltration and fluctuations from precipitation and evapotranspiration (ET) data. This study also …

Sh-Wave Seismic-Reflection Efficiency Technique For Investigating The Wolf Island Fault, New Madrid Seismic Zone, Usa, Stephanie Vicroy

Theses and Dissertations--Earth and Environmental Sciences

The Reelfoot Fault within the New Madrid seismic zone has displacement at seismogenic depth to which the surface expression has unequal displacement. Previous work identified northeast-oriented transpressional fault strands northeast of a bend in the scarp as evidence for a through-going shear-zone, acting as potential accommodation for the observed strain imbalance. This investigation projected the trend of these faults to their intersection with an industry seismic survey at Wolf Island, Missouri, which exhibits a similarly structured faulted zone. We suggest this structure is the continuation of the through-going shear zone representing a previously unknown 22-km-long Quaternary-active fault that can affect …

Estrogen Signaling Regulates The Sex Difference In Resynchronization To Abrupt Shifts Of The Light-Dark Cycle In A Mouse Model Of Jet Lag, Maria Venegas

Theses and Dissertations--Biology

The circadian system coordinates 24-hour cycles of internal biological processes with the environmental light-dark cycle. Abrupt shifts in the timing of the light-dark cycle misalign internal circadian clocks with the environment and cause jet lag until resynchronization occurs. The objective of this study was to investigate the mechanisms underlying sex differences in jet lag in mice. Female mice resynchronized faster than male mice to 6-hour advances and delays of the light-dark cycle, which mimicked eastward and westward travel, respectively. Circulating estradiol was necessary for rapid resynchronization in female mice since ovariectomized females resynchronized slower than mice treated with estradiol. We …

All Eyes On The Spiny Mouse: An Investigation Into Acomys Dimidiatus As A Model For Retinal Biology And Regeneration, Jessica D. Bills

Theses and Dissertations--Biology

The retina is a complex tissue with six types of neurons, supported by an intrinsic glia cell, that work in concert to input a visual stimulus and relay a visual message to the brain. Efficient communication between neurons is vital to this process and each neuron plays a significant role in vision. When retinal neurons degenerate, that visual signal is lost. Degenerative eye diseases affect the neurons of the retina in millions of people world-wide and can ultimately lead to blindness. While treatments are evolving, most are designed to prevent further damage; the field has yet to piece together how …

Alteration Of Ultramafic Lamprophyres And Its Effect On Rare Earth Element Distribution In The Illinois-Ketucky Fluorspar District, Zachary O. Walton

Theses and Dissertations--Earth and Environmental Sciences

The ultramafic lamprophyres of the Illinois-Kentucky Fluorspar District (IKFD) have been identified as a potential domestic source of rare earth elements (REEs). The present distribution of the REEs and the role of the carbonate alteration in the distribution of the REEs is poorly understood. Petrographic and geochemical analyses were employed to determine the nature of the mantle source region and timing of the carbonate mineralization. Ratios of ¹⁴³Nd/¹⁴⁴Nd vs. ⁸⁷Sr/⁸⁶Sr demonstrate that in addition to the intrusion of primitive magma into the crust, a melt was generated from a mantle source region metasomatized by …

Re-Examination Of A Middle Mississippian Carbonate Mud-Mound Complex From The Fort Payne Formation In South-Central, Kentucky, Maxwell Mickelson

Theses and Dissertations--Earth and Environmental Sciences

This study examines the origin of a 213-m (700-ft) long, Middle Mississippian, carbonate “mud-mound complex” in the Fort Payne Formation of south-central Kentucky. The complex’s well-exposed, easily accessible, and well-preserved nature provides an opportunity to understand how mounds like this developed during a time of sediment starvation, basinward of the largely abandoned Borden-Grainger Delta complex.

The mound complex is formed of small, accretionary mounds that accreted onto the flanks of an eroded structural high and onto the backs of each other, apparently for protection from storms. Each sub-mound is composed of micrite-rich wackestone, comprising one of two biofacies: 1) alternating …

High Resolution Sedimentary Investigations Of Extant Lakes In North America, John Dilworth

Theses and Dissertations--Earth and Environmental Sciences

Investigation of past lake environments forms the discipline of paleolimnology. Paleolimnological studies seek to evaluate geophysical, geochemical, and ecological proxies and indicators contained within lake sediment archives. Using these potential stores of high-resolution environmental information, questions regarding climate, biological, and geochemical changes experienced by a lake and its watershed can be investigated. This dissertation research utilized lake sediment records from two lakes within North America to study different aspects of environmental change. This dissertation consists of three separate studies presented in three chapters.

Chapter Two presents a retrospective environmental assessment of Jackson Lake, Wyoming to investigate the impacts of dam …

Crisis, Genre, And The Informatic Infrastructure Of The Critical Path Aids Project In Philadelphia's Early Epidemic, Sid Feinberg

Theses and Dissertations--Geography

The Critical Path AIDS Project was a grassroots information network that distributed AIDS-related information related to biomedicine, social services, and politics. I explore the ways the project made sense of the shattering social service and care landscapes they emerged within and responded to. I situate Critical Path’s work within Philadelphia’s splintering care infrastructures and the experience of crisis Lauren Berlant argues structures perception of neoliberal life. I focus on the ways that Critical Path’s articulation of crisis and spatial re-orientation pull on the modernist design work of Buckminster Fuller. Fuller’s design work formed a framework through which the project constructed …

Beauty And The Anthropocene: On The Emancipatory Potential Of Experiences Of Beautiful Places In The Natural World, Matthew John

Theses and Dissertations--Geography

This dissertation investigates the proposition that beauty—specifically, experiences of beautiful places in the natural world—can contribute to the emancipation of modern persons (and thereby developed societies) from instrumental rationality, which is theorized as a major driver of contemporary socioecological crises of the Anthropocene. Buber’s concept of the I–Thou relation provides a framework for conceptualizing ideal non-instrumental relations. The project’s methodology, rooted in post-phenomenology, consisted of semi-structured remote interviews and four follow-up focus groups with 35 then current and recently former residents of Juneau, Alaska. Taken together, data confirm that experiences of beautiful places in the natural world can and do …

A Geography Of Transgender Belonging In Louisville, Kentucky, Lj Mcallister

Theses and Dissertations--Geography

Louisville, Kentucky is home to a surprisingly robust – and complex – transgender community. This study uses qualitative data from interviews, collaborative maps, and archival research to analyze a geography of belonging for transgender residents in the city. It discusses how the twelve participants negotiate their relationships with the conservative, “red” state of Kentucky, as well as the geographical decision-making they use to navigate Louisville’s many neighborhoods. Ultimately, this thesis draws attention to the ways in which prejudice shapes the landscape of belonging for transgender life in Derby City.

The Nature Of Albanian Nasal-Stop Sequences: Phonetic, Phonological, Sociolinguistic & Historical Behavior, Patrick A. Gehringer

Theses and Dissertations--Linguistics

The Albanian language is relatively unique among the Indo-European languages with its word initial nasal-stop sequences. Despite broad characterizations, the phonetic, phonological, and sociolinguistic properties of these sequences have not been analyzed with the same rigor as languages with similar sequences. I employ phonetic, perceptual dialectological and historical methods to examine not only how these clusters are employed by speakers in today’s Albanian linguistic landscape, but also to the historical mechanisms and timing of the development of these clusters and their variants within Albanian. With a combined spectral and aerodynamic analysis, I have identified that these clusters are phonemically composed …

A Computer-Assisted Approach To Lexical Borrowing In Northeast Caucasian Languages, Bonnie Eleanor Wren-Hardin

Theses and Dissertations--Linguistics

The disambiguation of loanwords and cognates can be a challenge, especially in areas where there has been intense language contact over an extended period of time, when the contact is between genetically related languages, and when the number of languages involved is large Over the past several decades, more and more computational approaches to automatic cognate and borrowing detection have been created in an attempt to ease the load of examining hundreds to thousands of individual lexemes, as well as determine language family relationships with allegedly greater accuracy. While these methods are not perfect and cannot replace the knowledge or …

Beyond The Hands: Exploring Intersectional Identities Of Black American Sign Language Users, Tatum Turner

Theses and Dissertations--Linguistics

There is a significant gap in research related to the impact of intersectionality on linguistic identity performance among individuals negotiating multiple marginalized identities. This gap is especially significant among deaf Black and African American individuals who use the American Sign Language (ASL) variety deemed Black American Sign Language (BASL) (Hairston & Smith, 1983). This research aims to identify and discuss the use of the eight distinguishing features of BASL (McCaskill et al. 2011) as indexes of intersectional identities.

My data consists of videos sourced from YouTube, each chosen according to the following criteria: must have at least one self-identifying Black …

The Movie Is On!: Pragmatics Of The Video Joker In Who Killed Captain Alex?, Hunter Hulett

Theses and Dissertations--Linguistics

The film Who Killed Captain Alex? (WKCA) is a Ugandan film that provides an opportunity to examine the use of pragmatic and specifically deictic features to study the manipulation of borders between the film and reality. A commentator called the Video Joker (VJ) is the film’s deictic center, constantly destabilizing deictic relations and orienting the internal and external pragmatics of the film around themself. As the film’s ultimate pragmatic force, they occupy a position blurring diegesis and non-diegesis due to originating as real-time film commentators before being edited into the text. In this unique position, they shift the deixis’s organization …

La Nueva Argumentación De Twitter: El Cambio De Paradigma Retórico Y La Independencia De Catalunya En Tuits, David Cortes Ferrandez

Theses and Dissertations--Hispanic Studies

Technology changed our world and shapes our reality in forms that widely differ from the traditional ones. Discourse and persuasion are not an exception. This study analyzes the tweets and oral discourses of eight politicians and social leaders during three of the most important days in the independence struggle between Catalonia and Spain to argue that the way people in power try to persuade their voters is changing, especially in new social networks such as Twitter.

The main object of study are the argumentative and persuasion processes that take place both in Twitter and oral discourses from the same politicians …

"Many Fabulous Stories And Idle Tales": The Intersection Of Elizabethan Political Gambits And Indigenous Erasure In The Early American Republic, Daniel Ryan Lewis

Theses and Dissertations--History

Welsh Indian Theory, originating in Elizabethan England, stated that a group of Welsh explorers settled in the Americas in the late 12^th century and intermarried with the Indigenous tribes, thereby explaining “advanced cultures” ranging from the Mississippians to the Aztec Empire. This act of erasure became rooted in Kentucky and the surrounding area in the 18^th and 19^th centuries; a series of prominent individuals from Kentucky in turn contributed to a growing body of false historical narratives that denied Indigenous Americans their cultural identities and connection their ancestral lands in the United States. With a 460-year trail …

Confronting Yanqui Racismo: The Cuban Revolution And The (R)Evolutionary Radicalization Of Amiri Baraka, Ariane Ribeiro Santana

Theses and Dissertations--History

This study examined the July 1960 trip to Cuba financed by the Fair Play for Cuba Committee and the Cuban cultural center Casa de las Américas, in which the Black poet and activist Amiri Baraka took part. Diving into his experiences in Cuba and his later writings, it is possible to conceive of diaspora as an interaction that is based not only on race, but on points of common oppression, as seen between Baraka and the African American delegation he joined in 1960 and the Cuban society he engaged with during the trip. This work therefore furthers the field of …

“Taken At The Flood”: Happy Chandler, Race, And The Rise Of Modern Conservatism, 1932–1968, Christa Kieffer

Theses and Dissertations--History

This project focuses on the role of race in the construction of modern conservatism by examining the career of A. B. “Happy” Chandler. As governor of Kentucky, Chandler dedicated funds to send Black students to graduate school and sent the National Guard to protect Black students integrating all-white high schools, even threatening to declare martial law if anti-integrationists were to resort to violence. When he became the commissioner of Major League Baseball, he supported the breaking of the color barrier and allowed Jackie Robinson to enter the league. Chandler further promised to punish those who hurled racial slurs at Robinson …

Bicategorical Character Theory, Travis Wheeler

Theses and Dissertations--Mathematics

In 2007, Nora Ganter and Mikhail Kapranov defined the categorical trace, which they used to define the categorical character of a 2-representation. In 2008, Kate Ponto defined a shadow functor for bicategories. With the shadow functor, Dr. Ponto defined the bicategorical trace, which is a generalization of the symmetric monoidal trace for bicategories. How are these two notions of trace related to one another? We’ve used bicategorical traces to define a character theory for 2-representations, and the categorical character is an example.

Properties Of Skew-Polynomial Rings And Skew-Cyclic Codes, Kathryn Hechtel

Theses and Dissertations--Mathematics

A skew-polynomial ring is a polynomial ring over a field, with one indeterminate x, where one must apply an automorphism to commute coefficients with x. It was first introduced by Ore in 1933 and since the 1980s has been used to study skew-cyclic codes. In this thesis, we present some properties of skew-polynomial rings and some new constructions of skew-cyclic codes. The dimension of a skew-cyclic code depends on the degree of its generating skew polynomial. However, due to the skew-multiplication rule, the degree of a skew polynomial can be smaller than its number of roots and hence tricky to …

Adams Operations On The Burnside Ring From Power Operations, Lewis Dominguez

Theses and Dissertations--Mathematics

Topology furnishes us with many commutative rings associated to finite groups. These include the complex representation ring, the Burnside ring, and the G-equivariant K-theory of a space. Often, these admit additional structure in the form of natural operations on the ring, such as power operations, symmetric powers, and Adams operations. We will discuss two ways of constructing Adams operations. The goal of this work is to understand these in the case of the Burnside ring.

Pairs Of Quadratic Forms Over P-Adic Fields, John Hall

Theses and Dissertations--Mathematics

Given two quadratic forms $Q_1, Q_2$ over a $p$-adic field $K$ in $n$ variables, we consider the pencil $\mathcal{P}_K(Q_1, Q_2)$, which contains all nontrivial $K$-linear combinations of $Q_1$ and $Q_2$. We define $D$ to be the maximal dimension of a subspace in $K^n$ on which $Q_1$ and $Q_2$ both vanish. We define $H$ to be the maximal number of hyperbolic planes that a form in $\mathcal{P}_K(Q_1, Q_2)$ splits off over $K$. We will determine which values for $(D, H)$ are possible for a nonsingular pair of quadratic forms over a $p$-adic field $K$.

Dirichlet Problems In Perforated Domains, Robert Righi

Theses and Dissertations--Mathematics

We establish W^1,p estimates for solutions u_ε to the Laplace equation with Dirichlet boundary conditions in a bounded C¹ domain Ω_{ε, η} perforated by small holes in ℝ^d. The bounding constants will depend explicitly on epsilon and eta, where epsilon is the order of the minimal distance between holes, and eta denotes the ratio between the size of the holes and epsilon. The proof relies on a large-scale L^p estimate for ∇u_ε, whose proof is divided into two main parts. First, we show that solutions of an intermediate problem for a …

Uniform Regularity Estimates For The Stokes System In Perforated Domains, Jamison R. Wallace

Theses and Dissertations--Mathematics

We consider the Stokes equations in an unbounded domain $\omega_{\epsilon,\eta}$ perforated by small obstacles, where $\epsilon$ represents the minimal distance between obstacles and $\eta$ is the ratio between the obstacle size and $\epsilon$. We are able to obtain uniform $W^{1,q}$ estimates for solutions to the Stokes equations in such domains with bounding constants depending explicitly on $\epsilon$ and $\eta$.

Slₖ-Tilings And Paths In ℤᵏ, Zachery T. Peterson

Theses and Dissertations--Mathematics

An SLₖ-frieze is a bi-infinite array of integers where adjacent entries satisfy a certain diamond rule. SL₂-friezes were introduced and studied by Conway and Coxeter. Later, these were generalized to infinite matrix-like structures called tilings as well as higher values of k. A recent paper by Short showed a bijection between bi-infinite paths of reduced rationals in the Farey graph and SL₂-tilings. We extend this result to higher k by constructing a bijection between SLₖ-tilings and certain pairs of bi-infinite strips of vectors in ℤᵏ called paths. The key ingredient in the proof is the relation to Plucker friezes and …

A Multiple-Case Study On The Impact Of An Introductory Real Analysis Course On Undergraduate Students' Understanding Of Function Continuity, Ryan Joseph Rogers

Theses and Dissertations--Mathematics

Undergraduate students' understanding of function continuity has not been explored broadly in previous research. The relevant findings in the literature are predominantly concerned with calculus students' understanding and misconceptions of continuity. Many of these misunderstandings are tied to the relationships which continuity has with limits and differentiability. This multiple-case study explores how, if at all, an introductory real analysis course impacts undergraduate students' understanding of function continuity and its connections to the notions of limits and differentiability. We embed our findings within the theoretical framework of Tall's three worlds of mathematics, namely, the embodied, symbolic, and formal worlds.

The cases …

Advanced Mathematical Graph-Based Machine Learning And Deep Learning Models For Drug Design, Farjana Tasnim Mukta

Theses and Dissertations--Mathematics

Drug discovery is a highly complicated and time-consuming process. One of the main challenges in drug development is predicting whether a drug-like molecule will interact with a specific target protein. This prediction accelerates target validation and drug development. Recent research in biomolecular sciences has shown significant interest in algebraic graph-based models for representing molecular complexes and predicting drug-target binding affinity. In this thesis, we present algebraic graph-based molecular representations to create data-driven scoring functions (SF) using extended atom types to capture wide-range interactions between targets and drug candidates. Our model employs multiscale weighted colored subgraphs for the protein-ligand complex, colored …

Advancements In Elliptic Mesh Redistribution And Automated Overset Grid Generation For Computational Fluid Dynamics, Chase Ashby

Theses and Dissertations--Mathematics

Automated and robust structured curvilinear overset grid generation remains a significant challenge for the application of computational fluid dynamics. This thesis intro- duces a specialized anisotropic Mach cone aligned adaptation algorithm for low-boom simulations and an automated procedure for generating structured curvilinear overset grids for immersed boundary simulations. Results demonstrate that anisotropic mesh adaptation can reduce computational resource usage by over 50% while maintaining sonic boom prediction accuracy across the entire sonic boom domain compared to user-constructed Mach cone aligned grids. The proposed immersed overset grid gen- eration procedure eliminates the need for complex surface generation algorithms, producing grids suitable …