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Use Of Image Processing Techniques And Machine Learning For Better Understanding Of T Gondii Biology, Amer Asiri

Theses and Dissertations--Biomedical Engineering

Almost one in every three people worldwide is infected with Toxoplasma gondii (T. gondii). The biology and growth of the parasite’s bradyzoite form in host tissue cysts are not well understood. T. gondii’s metabolic state influences the morphology of its single mitochondrion, which can be visualized using fluorescence microscopy with specific dyes. Hence, fluorescence microscopy images of cysts purified from infected mouse brains carry biological information about bradyzoites, the poorly understood form of the parasite within them. With the help of fluorescence microscopy techniques, previous studies extracted images of the mitochondrion, nucleus, and the inner membrane complex (IMC) …

Sewer Vapor Intrusion Pathway: Simulation Of Indoor Piping Systems And Operation Of Aroma-Voc Gas Analyzer, Hong Cheng Tay

Theses and Dissertations--Civil Engineering

Vapor Intrusion (VI) is a transport phenomenon that occurs when contaminants migrate from sub-surface sources into indoor spaces. Sewer tunnels, plumbing connections, and piping infrastructures can be important contributors to an increased potential of VI in a site, which results in indoor concentrations of volatile organic compounds (VOC). In the present work, the topic of sewer VI pathways were investigated through a prototype made from various types of indoor plumbing pipe fittings. This prototype simulates indoor piping systems and determine whether air and VOC were escaping through the pipe fittings. Moreover, this study is the first effort to use a …

A Computational Exploration Of The Scandate Cathode Surface, Shankar Miller-Murthy

Theses and Dissertations--Chemical and Materials Engineering

The exact surface configuration of scandate cathodes has been a point of contention for the materials community for a long time. Without proper understanding of it and the related structures and emission mechanisms, scandate cathodes remain patchy and unreliable emitters. Thus, density functional theory techniques were applied to various potential surface arrangements and found that there are several low-energy surfaces with low work functions that incorporate a scandium interlayer between tungsten and oxygen or otherwise have a scandium-on-tungsten structure. Furthermore, it was discovered that adding a monolayer of scandium directly to a tungsten surface is surprisingly favorable, thermodynamically. While none …

The Performance Optimization Of Asp Solving Based On Encoding Rewriting And Encoding Selection, Liu Liu

Theses and Dissertations--Computer Science

Answer set programming (ASP) has long been used for modeling and solving hard search problems. These problems are modeled in ASP as encodings, a collection of rules that declaratively describe the logic of the problem without explicitly listing how to solve it. It is common that the same problem has several different but equivalent encodings in ASP. Experience shows that the performance of these ASP encodings may vary greatly from instance to instance when processed by current state-of-the-art ASP grounder/solver systems. In particular, it is rarely the case that one encoding outperforms all others. Moreover, running an ASP system on …

Don't Give Me That Story! -- A Human-Centered Framework For Usable Narrative Planning, Rachelyn Farrell

Theses and Dissertations--Computer Science

Interactive or branching stories are engaging and can be embedded into digital systems for a variety of purposes, but their size and complexity makes it difficult and time-consuming for humans to author them. Narrative planning algorithms can automatically generate large branching stories with guaranteed causal consistency, using a hand-authored library of story content pieces. The usability of such a system depends on both the quality of the narrative model upon which it is built and the ability of the user to create the story content library.

Current narrative planning algorithms use either a limited or no model of character belief, …

Distribution Of Particulate Organic Carbon – Fluxes And Inventories – In Growth-Faulted Coastal Wetlands, Samuel Joel Whitehead

Theses and Dissertations--Earth and Environmental Sciences

Coastal wetlands along the Northern Gulf of Mexico (NGOMx) are critically important but threatened environments which provide significant and diverse economic, social, and environmental value. These environments are essential components to the global carbon cycle, serving as one of the most efficient terrestrial carbon sinks. Since onset of the Industrial Revolution increasing rates of coastal wetland loss have been documented due to a variety of anthropogenic activities, neotectonic processes, subsidence, and rising sea-levels. This research utilized an array of methods and sedimentological analyses to test the hypothesis that growth-fault induced changes at Earth’s surface affects the delivery to, and storage …

The Revised Systematics And Paleoecology Of The Devonian Stemless Crinoid Genus Edriocrinus Hall, 1858, Catherine E. Herbert

Theses and Dissertations--Earth and Environmental Sciences

New morphological observations of Edriocrinus Hall, 1858, enable a modern, holistic view of this unusual crinoid genus, previously included in the Superorder Flexibilia (Zittel, 1895) Wright et al., 2017. Re-analysis of Edriocrinus suggests that the genus should now be assigned to the Order ‘Dendrocrinida’ within the Magnorder Eucladida Wright, 2017 based on the five infrabasals, single radianal in the cup, absent anal sac, and non-pinnulate arms with rectangular uniserial brachials. Moreover, examination of the slight variations separating the current 14 Edriocrinus species indicates that these “species” are likely ecophenotypes. The current Edriocrinus species are revised based on firmly bound calyx …

Naturally Occurring And Introduced Tracers For Examining Water Pathways In Urban Environments, Elizabeth Avery

Theses and Dissertations--Earth and Environmental Sciences

Naturally occurring stable isotopes of water and introduced water tracers allow researchers to examine water pathways and better understand spatial and temporal variability in water sources. Trends in naturally occurring stable isotope values can function not only as a tracer for precipitation patterns and moisture recycling but also as a confirmation of municipal data. Additionally, these data can provide an early signal for the effects of climate change on these sources, reducing uncertainty from physical measurements. To further assess water pathways, introduced tracers can be used to investigate surface and below ground surface flow for streams and rivers.

In chapter …

Deformation Of Wall Rocks And Overburden Sequences Proximal To Salt Diapirs In Salt Valley, Utah: Implications For Predicting Subseismic Damage In Salt Tectonic Systems, William Swanger

Theses and Dissertations--Earth and Environmental Sciences

Although deformation related to salt tectonics is generally considered to be an ancillary field of structural geology, owing to its relatively limited occurrence in the geologic record, the preponderance of salt-involved systems in multiple hydrocarbon-rich basins around the world (e.g., Gulf of Mexico, Atlantic passive margins, Iran, etc.) creates a necessity for understanding salt-related deformation. Traditionally, salt was considered to be relatively weak and thus was mostly unable to drive deformation of adjacent wall rocks and cover sequences. However, a number of recent numerical modeling studies have shown that mobilized and pressurized salt may have the ability to actively pierce …

Tryptophan-Like Fluorescence And Non-Point Source Pollution In Karst Basins, Inner Bluegrass Region, Kentucky, Ryan Dapkus

Theses and Dissertations--Earth and Environmental Sciences

Typically, the degree of fecal contamination of water is assessed by the concentration of thermotolerant coliforms, like E. coli. This method is time-consuming, taking > 18 hours between the start of incubation and subsequent enumeration. The current study examines the utility of monitoring tryptophan-like fluorescence (TLF) using in-situ fluorometers as a proxy for fecal contamination, particularly E. coli. Relative timing of discharge peaks and TLF peaks is considered, as well as differences in E. coli concentrations and major anion concentrations between two different basins that were monitored weekly. Results indicate that TLF is somewhat useful in the prediction of …

Syn- To Post-Orogenic Evolution Of Collisional Mountain Systems: Investigating The Potential For Crustal Flow Using Thermochronology And Numerical Models, Brandon Spencer

Theses and Dissertations--Earth and Environmental Sciences

This dissertation is composed of three distinct manuscripts which collectively investigate processes that contribute to the late evolution of collisional mountain systems —specifically, the ancient Appalachian-Caledonian system. In the first paper, ⁴⁰Ar/³⁹Ar thermochronological data are used to constrain the timing of exhumation of the Scandian orogenic wedge of northern Scotland. Muscovite and amphibole samples yield dates of ca. 420-411 Ma, consistent with cooling after peak orogenesis. During this cooling phase, dates from both systems in individual thrust sheets show an increase in cooling rate in the later stage of exhumation; in the orogenic core, the cooling rate …

Geometric Properties Of Weighted Projective Space Simplices, Derek Hanely

Theses and Dissertations--Mathematics

A long-standing conjecture in geometric combinatorics entails the interplay between three properties of lattice polytopes: reflexivity, the integer decomposition property (IDP), and the unimodality of Ehrhart h*-vectors. Motivated by this conjecture, this dissertation explores geometric properties of weighted projective space simplices, a class of lattice simplices related to weighted projective spaces.

In the first part of this dissertation, we are interested in which IDP reflexive lattice polytopes admit regular unimodular triangulations. Let Delta_(1,q)denote the simplex corresponding to the associated weighted projective space whose weights are given by the vector (1,q). Focusing on the case where Delta …

Batch Normalization Preconditioning For Neural Network Training, Susanna Luisa Gertrude Lange

Theses and Dissertations--Mathematics

Batch normalization (BN) is a popular and ubiquitous method in deep learning that has been shown to decrease training time and improve generalization performance of neural networks. Despite its success, BN is not theoretically well understood. It is not suitable for use with very small mini-batch sizes or online learning. In this work, we propose a new method called Batch Normalization Preconditioning (BNP). Instead of applying normalization explicitly through a batch normalization layer as is done in BN, BNP applies normalization by conditioning the parameter gradients directly during training. This is designed to improve the Hessian matrix of the loss …

Tropical Geometry Of T-Varieties With Applications To Algebraic Statistics, Joseph Cummings

Theses and Dissertations--Mathematics

Varieties with group action have been of interest to algebraic geometers for centuries. In particular, toric varieties have proven useful both theoretically and in practical applications. A rich theory blending algebraic geometry and polyhedral geometry has been developed for T-varieties which are natural generalizations of toric varieties. The first results discussed in this dissertation study the relationship between torus actions and the well-poised property. In particular, I show that the well-poised property is preserved under a geometric invariant theory quotient by a (quasi-)torus. Conversely, I argue that T-varieties built on a well-poised base preserve the well-poised property when the base …

The V1-Periodic Region In Complex Motivic Ext And A Real Motivic V1-Selfmap, Ang Li

Theses and Dissertations--Mathematics

My thesis work consists of two main projects with some connections. In the first project we establish a v₁ periodicity theorem in Ext over the complex motivic Steenrod algebra. The element h₁ of Ext, which detects the homotopy class \eta in the motivic Adams spectral sequence, is non-nilpotent and therefore generates h₁-towers. Our result is that, apart from these h₁-towers, v₁ periodicity operators give isomorphisms in a range near the top of the Adams chart. This result generalizes well-known classical behavior.

In the second project we consider a nontrivial action of C_{2 …}

Out Of Sight, Out Of Mind: An Evaluation Of Secondary Agricultural Textbooks, Tara Elizabeth Rojas

Theses and Dissertations--Community & Leadership Development

Students are impacted by representation present within their lives in the media they consume, organizations in which they participate, and school interactions. Among school interactions with primarily White school staff, students interact with textbooks to learn about industry norms and concepts. Missing representation can harm students’ sense of belonging which can lead to feelings like solo-status or isolation. Using both critical race theory and social semiotics, this work explores the representation present within secondary agricultural textbooks. The first study utilizes photos and case studies, observing both gender and race as mutually exclusive variables and compares data to the current public-school …

Multivariate Statistical Modeling For Radio-Genomics Study, Tiantian Zeng

Theses and Dissertations--Statistics

Radiogenomics is a new direction in cancer research that focuses on the associations among radiomics, genomics and clinical outcome. Currently, the major challenge for Radiogenomics lies in the effective integration of genomics and imaging data for promising clinical outcome prediction. Herein, we propose a multivariate joint model that can integrate imaging and genomic data for better predicting the clinical outcome. Specifically, we jointly consider two multivariate group lasso models, one regresses imaging features on genomic features, and the other regresses patient’s clinical outcome on genomic features. An L1 penalty term is introduced for each variable, and weight in the penalty …

Statistical Theory For Specialized Linear Regression Adjustment Methods Compared To Multiple Linear Regression In The Presence And Absence Of Interaction Effects, Leon Su

Theses and Dissertations--Statistics

When building models to investigate outcomes and variables of interest, researchers often want to adjust for other variables. There is a variety of ways that these adjustments are performed. In this work, we will consider four approaches to adjustment utilized by researchers in various fields. We will compare the efficacy of these methods to what we call the ”true model method”, fitting a multiple linear regression model in which adjustment variables are model covariates. Our goal is to show that these adjustment methods have inferior performance to the true model method by comparing model parameter estimates, power, type I error, …

Deriving The Distributions And Developing Methods Of Inference For R2-Type Measures, With Applications To Big Data Analysis, Gregory S. Hawk

Theses and Dissertations--Statistics

As computing capabilities and cloud-enhanced data sharing has accelerated exponentially in the 21st century, our access to Big Data has revolutionized the way we see data around the world, from healthcare to investments to manufacturing to retail and supply-chain. In many areas of research, however, the cost of obtaining each data point makes more than just a few observations impossible. While machine learning and artificial intelligence (AI) are improving our ability to make predictions from datasets, we need better statistical methods to improve our ability to understand and translate models into meaningful and actionable insights.

A central goal in the …

Beta Mixture And Contaminated Model With Constraints And Application With Micro-Array Data, Ya Qi

Theses and Dissertations--Statistics

This dissertation research is concentrated on the Contaminated Beta(CB) model and its application in micro-array data analysis. Modified Likelihood Ratio Test (MLRT) introduced by [Chen et al., 2001] is used for testing the omnibus null hypothesis of no contamination of Beta(1,1)([Dai and Charnigo, 2008]). We design constraints for two-component CB model, which put the mode toward the left end of the distribution to reflect the abundance of small p-values of micro-array data, to increase the test power. A three-component CB model might be useful when distinguishing high differentially expressed genes and moderate differentially expressed genes. If the null hypothesis above …

Building Tools For Improved Modulation Of The Human Gabaa Receptor, A Central Nervous System Target For The Treatment Of Anxiety, Garrett Edward Zinck

Theses and Dissertations--Pharmacy

In the U.S., anxiety is recognized as an increasing range of mentally and physically debilitating psychiatric health disorders with significant economic repercussions. Over the last 20 years, several novel anti-anxiety therapies have entered the drug development pipeline, but none have made it to market.

The work in this dissertation focused on structurally modifying valerenic acid (VA), a structurally unique carboxylated sesquiterpene acid found in Valeriana officinalis. VA is putatively reported to have allosteric modulatory activity of the human GABA_A receptor, a ligand-gated ion channel responsible for attenuating neurotransmissions. Structural modeling of VA’s GABA_A receptor interaction suggests that …

Investigating The Physical Stability Of Amorphous Pharmaceutical Formulations, Travis W. Jarrells

Theses and Dissertations--Pharmacy

Amorphous formulations, including amorphous solid dispersions (ASDs), consisting of the active pharmaceutical ingredient (API) intimately mixed in a polymeric matrix, are an attractive formulation approach to improve drug delivery, dissolution, and solubility. However, an amorphous API in an ASD is in a higher energy state compared to the crystalline drug and results in most ASDs being inherently unstable. The polymer helps to stabilize the amorphous drug against crystallization such that the resulting homogenous mixture maintains its solubility advantage relative to the crystalline form. One challenge of ASDs is that the presence of impurities including crystals or residual solvent, variations in …

Development Of Accurate And Efficient Computational Methodologies For Predicting Protein-Ligand And Protein-Protein Binding Free Energies, Alexander Hamilton Williams

Theses and Dissertations--Pharmacy

Computational modeling is an invaluable tool in the drug discovery process either for small ligand or protein therapeutics. The widespread availability of protein X-Ray Crystal and Cryo-Electron Microscopy (Cryo-EM) structures has allowed for more accurate molecular dynamics (MD) simulations that are not reliant on methods such as homology modeling, which may produce structures that require significant computational time to demonstrate their stability. In this thesis we describe several novel methodologies for the computationally efficient modeling of protein/ligand and protein/protein complexes that may be employed within both large-scale virtual screenings and lead compound optimization. These methodologies may also be utilized in …

Addressing Ascertainment Bias In The Study Of Cardiovascular Disease Burden In Opioid Use Disorders - Application Of Natural Language Processing Of Electronic Health Records, Jade Huang Singleton

Theses and Dissertations--Epidemiology and Biostatistics

In the United States, the prevalence of long-term exposure to opioid drugs, for both medically and nonmedically indicated purposes, has increased considerably since the mid-1990’s. Concerns have emerged about the potential health effects of opioid use. There is also growing interest in other possible connections with opioid use including cardiovascular disease. Electronic health records (EHR) contain information about patient care in the form of structured codes and unstructured notes. Natural language processing (NLP) provides a tool for processing unstructured textual data in EHR clinical notes and extracts useful information for research with structured formats. The purpose of this dissertation was …

Opioid Use Disorder Treatment With Buprenorphine: Analysis Of Treatment Utilization And Associated Outcomes In Kentucky, Feitong Lei

Theses and Dissertations--Epidemiology and Biostatistics

Opioid use disorder (OUD) is chronic opioid use that results in clinically significant suffering, impairment, or even death. The opioid epidemic in the United States has become a public health and economic crisis, affecting patients' well-being and the nation's overall health and welfare. Eastern Kentucky was among the first regions affected by the opioid crisis, and Kentucky has historically ranked among the top five states for age-adjusted drug overdose mortality rate.

There are three medications (buprenorphine, methadone, naltrexone) approved by the U.S. Food and Drug Administration to treat OUD. As a partial opioid agonist, buprenorphine is a safe medication for …

Development Of Univariate And Multivariate Forecasting Models For Methane Gas Emissions In Underground Coal Mines, Juan Diaz

Theses and Dissertations--Mining Engineering

Methane gas management continues to be a challenge concerning underground coal mine safety and productivity worldwide despite the extraordinary effort of the mining industry, governmental agencies, and academia to develop new technologies to monitor and control methane gas emissions more efficiently. The risk of hazardous methane gas concentrations in underground environments cannot be underestimated. Statistical data for the last 100 years indicate that around 80% of the accidents and 90% of the fatalities in the underground coal mining industry in the US were related to methane gas explosions.

Modern underground mine operations monitor and evaluate atmospheric parameters such as barometric …

Parametric Numerical Analysis Of Inclined Coal Pillars, Robin Flattery

Theses and Dissertations--Mining Engineering

Pillars are used as the primary support structures for underground mining to maintain stability by supporting the over laying strata. In the case of horizontal seams, the pillars are typically subjected to axial loading due to the weight of the overburden and/or abutment stresses, while in the case of inclined seams they are subjected to oblique loading due to both the vertical and horizontal in-situ stress. Over the years numerous studies have been completed on square and rectangular pillars in horizontal seams that have resulted in several pillar stability equations and criteria. However very few studies are available with respect …

Investigation Into, & Analysis Of Temperature & Strain Data For Coal Mine Seal Material During Curing, Stephanus Jaco Van Den Berg

Theses and Dissertations--Mining Engineering

On Monday, January 2, 2006, an underground explosion occurred at the Sago Mine WV, resulting in the death of 12 miners and seriously injury to one miner. On Saturday, May 20, 2006, an underground explosion occurred at the Darby Mine No.1 KY, resulting in five miner’s deaths and one miner’s injury.

The explosion of methane gas and coal dust result in many fatalities in the coal mining industry.

The coal mining industry uses mine seals to optimize the ventilation network. Those structures are designed not only to direct the air appropriately, but also, they should be capable of withstanding some …

Development Of Univariate And Multivariate Forecasting Models For Methane Gas Emissions In Underground Coal Mines, Juan Diaz

Theses and Dissertations--Mining Engineering

Methane gas management continues to be a challenge concerning underground coal mine safety and productivity worldwide despite the extraordinary effort of the mining industry, governmental agencies, and academia to develop new technologies to monitor and control methane gas emissions more efficiently. The risk of hazardous methane gas concentrations in underground environments cannot be underestimated. Statistical data for the last 100 years indicate that around 80% of the accidents and 90% of the fatalities in the underground coal mining industry in the US were related to methane gas explosions.

Modern underground mine operations monitor and evaluate atmospheric parameters such as barometric …

Numerical Investigation Of An Oxyacetylene Torch With Regards To An Ablative Material, Luke Fortner

Theses and Dissertations--Mechanical and Aerospace Engineering

A computational fluid dynamic (CFD) software is used to model an oxyacetylene torch used as a screening facility for high temperature material testing. First, a published test-case is used to verify the CFD approach. The model that was produced falls within 5% of the Marra et al. [15] work in regards to heat flux and front face temperature, with a one step reaction mechanism that is computationally cheap. Then, the approach is used to model an existing experimental facility.