Digital Commons Network^™

Bnclassify: Learning Bayesian Network Classifiers, Bojan Mihaljević, Concha Bielza, Pedro Larrañaga

The R Journal

The bnclassify package provides state-of-the art algorithms for learning Bayesian network classifiers from data. For structure learning it provides variants of the greedy hill-climbing search, a well-known adaptation of the Chow-Liu algorithm and averaged one-dependence estimators. It provides Bayesian and maximum likelihood parameter estimation, as well as three naive-Bayes specific methods based on discriminative score optimization and Bayesian model averaging. The implementation is efficient enough to allow for time-consuming discriminative scores on medium sized data sets. The bnclassify package provides utilities for model evaluation, such as cross-validated accuracy and penalized log-likelihood scores, and analysis of the underlying networks, including network …

Explanations Of Model Predictions With Live And Breakdown Packages, Mateusz Staniak, Przemysław Biecek

The R Journal

Complex models are commonly used in predictive modeling. In this paper we present R packages that can be used for explaining predictions from complex black box models and attributing parts of these predictions to input features. We introduce two new approaches and corresponding packages for such attribution, namely live and breakDown. We also compare their results with existing implementations of state-of-the-art solutions, namely, lime (Pedersen and Benesty, 2018) which implements Locally Interpretable Model-agnostic Explanations and iml (Molnar et al., 2018) which implements Shapley values.

Downside Risk Evaluation With The R Package Gas, David Ardia, Kris Boudt, Leopoldo Catania

The R Journal

Financial risk managers routinely use non–linear time series models to predict the downside risk of the capital under management. They also need to evaluate the adequacy of their model using so–called backtesting procedures. The latter involve hypothesis testing and evaluation of loss functions. This paper shows how the R package GAS can be used for both the dynamic prediction and the evaluation of downside risk. Emphasis is given to the two key financial downside risk measures: Value-at-Risk (VaR) and Expected Shortfall (ES). High-level functions for: (i) prediction, (ii) backtesting, and (iii) model comparison are discussed, and code examples are provided. …

Rfsa: An R Package For Finding Best Subsets And Interactions, Joshua Lambert, Liyu Gong, Corrine F. Elliott, Katherine Thompson, Arnold Stromberg

The R Journal

Herein we present the R package rFSA, which implements an algorithm for improved variable selection. The algorithm searches a data space for models of a user-specified form that are statistically optimal under a measure of model quality. Many iterations afford a set of feasible solutions (or candidate models) that the researcher can evaluate for relevance to his or her questions of interest. The algorithm can be used to formulate new or to improve upon existing models in bioinformatics, health care, and myriad other fields in which the volume of available data has outstripped researchers’ practical and computational ability to explore …

Timing And Formation Of Linear Dunes South Of The Niobrara River Valley, North-Central Nebraska Sand Hills, Ashley K. Larsen

Department of Geography: Dissertations, Theses, and Student Research

The Nebraska Sand Hills is a vast (7,500 square kilometer) area of grass-stabilized sand dunes. Larger dunes in the Nebraska Sand Hills formed primarily during the Late Pleistocene, but many underwent widespread reactivation during the Holocene. Recent Optically Stimulated Luminescence (OSL) dating indicates that the last major phase of reactivation in the Sand Hills was during the Medieval Warm Period, approximately 800 years ago. Nevertheless, many questions about the evolution of the dunes remain unanswered, particularly regarding the formation of linear dunes in portions of the Sand Hills.

This study seeks to understand more about the formation of linear dunes …

Comparison Of Northern Flying And Red Squirrel Phylogenies With Focus On The Insular United States, Alyssa M. Kiesow, Hugh B. Britten

The Prairie Naturalist

Northern flying squirrel (Glaucomys sabrinus) and red squirrel (Tamiasciurus hudsonicus) populations are endemic to northern North America, including the Black Hills. The Black Hills populations are considered disjunct from other populations within their range. We examined insular populations to determine whether arboreal squirrels in the Black Hills each represent a unique population. We trapped and collected ear samples from northern flying and red squirrels in the Black Hills and in areas of Montana, Wyoming, Idaho, Utah, Minnesota, and Wisconsin to infer population phylogenies with special consideration of the Black Hills population. Microsatellite loci and two mtDNA sequences were used for …

Does Machismo Culture Influence Latina/O Attitudes On Mental Health?, Amanda R. Mercado

Theses and Dissertations

This study represents an attempt to contribute to the identified gap in knowledge towards the effects of machismo on both Latina women and Latino men and how it effects their attitudes towards mental health. The idea that previous research on machismo has been so one-sided, but has revealed that psychological distresses were present and ignored, leaves room for my research to explore how Latina women are affected because they are just as susceptible to psychological distresses as men. By using a research based framework to explain the effects of machismo on both Latina women and Latino men, my study will …

Seismicity In Nebraska And Adjacent States: The Historical Perspective And Current Trends, Irina Filina, Kris Guthrie, Mindi Searls, Caroline M. Burberry

Department of Earth and Atmospheric Sciences: Faculty Publications

A sudden spike in earthquake events has been observed in central Nebraska. Since April 2018, 26 earthquakes with equivalent moment magnitudes from 2.7 to 4.1 occurred, clustered tightly in Custer County. A similar cluster of 24 earthquakes with equivalent moment magnitudes from 2.6 to 3.7 occurred in Jewell County in northern Kansas in 2017. We have compiled an earthquake database for Nebraska and parts of adjacent states from different sources to determine whether these recent earthquake spikes are consistent with historic seismicity. We identified two historic earthquake clusters occurring in our study area. The first contained 32 events and was …

Multiple-Micronutrient Supplementation: Evidence From Large-Scale Prenatal Programmes On Coverage, Compliance And Impact, Cristiana Berti, Michelle F. Gaffey, Zulfiqar Ahmed Bhutta, Irene Cetin

Department of Paediatrics and Child Health

Micronutrient deficiencies during pregnancy pose important challenges for public-health, given the potential adverse outcomes not only during pregnancy but across the life-course. Provision of iron-folic acid (IFA) supplements is the strategy most commonly practiced and recommended globally. How to successfully implement IFA and multiple micronutrient supplementation interventions among pregnant women and to achieve sustainable/permanent solutions to prenatal micronutrient deficiencies remain unresolved issues in many countries. This paper aims to analyse available experiences of prenatal IFA and multiple micronutrient interventions to distil learning for their effective planning and large-scale implementation. Relevant articles and programme-documentation were comprehensively identified from electronic databases, websites …

Designing Selection Systems To Reduce Turnover, Joshua David Bush

Theses and Dissertations

This study sought to explore and predict voluntary turnover as a critical dependent variable in selection systems. I describe how using competency modeling to build measures of person-organization (P-O) fit may serve as a theoretical launching point for designing selection assessments to predict voluntary turnover. I tested this theoretical framework by analyzing an archival selection database of 3,332 current and former employees who went through a competency model-based selection system, which includes five different assessment methods all designed to measure P-O fit. I hypothesized that scores on these assessments would negatively predict turnover risk because research has demonstrated a strong …

An Examination Of Generational And Gender Differences Among Baby Boomers On The Scale Of Accurate Personality Perception (Sapp), Nicole Lane Murray

Theses and Dissertations

Generations and their differences, as well as the construct of self-knowledge, have been studied at length due to their potential predictive power over an individual’s behaviors. This research proposes to build upon these constructs by blending them together in order to see the differences that exist on various personality dimensions, as well as on self-knowledge, between the Baby Boomer generation and the general population. In order to test these hypotheses, archival data were used. Participants in the archival data set were grouped based on their generation depending on the year of their birth. The federal government, specifically the U.S. Census …

Dispersion Analysis Of Hdg Methods, Jay Gopalakrishnan, Manuel Solano, Felipe Vargas

Mathematics and Statistics Faculty Publications and Presentations

This work presents a dispersion analysis of the Hybrid Discontinuous Galerkin (HDG) method. Considering the Helmholtz system, we quantify the discrepancies between the exact and discrete wavenumbers. In particular, we obtain an analytic expansion for the wavenumber error for the lowest order Single Face HDG (SFH) method. The expansion shows that the SFH method exhibits convergence rates of the wavenumber errors comparable to that of the mixed hybrid Raviart–Thomas method. In addition, we observe the same behavior for the higher order cases in numerical experiments.

The History And Signification Of The Navicella Mosaic At St. Peter's Basilica, Rome., Eston Dillon Adams

Electronic Theses and Dissertations

The Navicella mosaic is most famously an artwork created by Giotto di Bondone. Evidence for the appearance and dating of this giant mural is discussed in this dissertation with the conclusion that it was made in 1298 and its composition is best recorded in a Parri Spinelli drawing preserved in the Musée Condé in Chantilly, France. It was admired by untold numbers of worshipers who visited the grand Constantinian basilica of Old St. Peter’s in the Vatican in Rome. The Navicella was located on the façade of Santa Maria in the Towers, an important chapel as well as the gatehouse …

Student Voices: African American High School Seniors' Perception Of Culturally Responsive Teaching., Whitney M. Stewart

Electronic Theses and Dissertations

This dissertation examined African-American high school seniors’ perceptions of culturally responsive teaching in one public high school within a large urban public-school district in the southeastern region of the United States. It begins with a brief historical overview on the plight of African-Americans in the US public education system and how public school educators have failed to leverage Afrocultural learning orientations as an asset to educate and increase the academic achievement of African-American students in classrooms. The Philosophical Aspects of Cultural Difference Framework (Nichols, 1986, 1995) will guide this dissertation study. The latter part of the dissertation reveals that a …

Conquerors Or Cowards: The Role Of The Kentucky Mounted Militia In The Indian Wars From 1768 To 1841., Joel Anderson

Electronic Theses and Dissertations

The thesis argues that Kentuckians developed the myth that the Kentucky Mounted Volunteers were the most effective troops to fight Native American warriors in the Northwest Indian War of 1790 to 1794 and the War of 1812. The idea that these troops were the best fighters originated in the decades following the War of 1812 as Kentuckians generated a communal history. Residents of the state listened to orators mythologize the successes of mounted Kentuckians in battle, while remembering the foot militia for their sacrifices rather than their shortcomings.

The Unequal City: The Mass Criminalization Of The Urban Poor., Elizabeth Michele Jones

Electronic Theses and Dissertations

Exploring and understanding the widespread use of arrests and incarceration in urban neighborhoods of concentrated poverty is the subject of this dissertation. The research addresses gaps in theoretical debates about the causes of mass criminalization that position the phenomenon as the result of either neoliberalism or racism. In addition, the dissertation explores the impact of mass criminalization on urban citizenship. Urban citizenship is a theoretical frame that considers the substance of the economic, social, political, and mobility dimensions of city life. The research methodology is a case study of two impoverished neighborhoods in the city of Louisville, Kentucky that incorporates …

North American Indigenous Collection And Curation And Its Impact On Market Arts., Adelaide Mccomb

Electronic Theses and Dissertations

This thesis examines the history of two North American Indigenous groups, those belonging to the Great Plains and the Arctic, and observes how settler-colonial influence determined the collection and curation of arts and artifacts in these areas. This art includes a mention of pre-Colombian works, but focuses predominantly on works being made after “first-contact” through the contemporary ear. The paper addresses the effect imperialist history has had on the development of Indigenous art markets, and how institutions such as museums may address them through ethical practices, and efforts to decolonize museum spaces.

Low Temperature Desiccants In Atmospheric Water Generation., Sunil Gupta

Electronic Theses and Dissertations

Surging global water demand as well as changes to weather patterns and over exploitation of natural water sources, such as ground water, has made potable water a critical resource in many parts of the World already – one rapidly heading towards a crisis situation. Desalination has been adopted as a solution – this is however energy intensive and impractical for most of the developing countries - those most in need of water. A renewable source of energy is solar thermal and solar photovoltaic. A plentiful source of water is the humidity in the atmosphere. This research is to push the …

Microaggressions In Lgb Individuals: The Protective Role Of Positive Lgb Identity., Ghazel Tellawi

Electronic Theses and Dissertations

The purpose of the current study was to examine LGB identity from a multidimensional approach in the context of microaggressions. The aims of the study were as follows: 1) to examine whether positive and negative facets of LGB identities are correlated; 2) to determine whether positive LGB identity facets served as protective factors against the negative impact of microaggressions; 3) to explore the unique contribution of having a positive LGB identity against the negative impact of microaggressions when compared to other protective factors (social support and outness). Participants were 135 undergraduate students recruited through the University of Louisville’s research participant …

Counter Narratives: A Phenomenological Study Of High Achieving African American Male High School Students., De'nay Lanise Speaks

Electronic Theses and Dissertations

This dissertation examined the contributing factors to the success of high achieving African American male high school students who attend an all-male, predominantly Black, college-preparatory academy. The study took place in an urban, Midwestern school district and highlighted the lived experience and perspectives of students who have at least a 3.0 grade point average. Through the lens of Critical Race Theory, this study was an effort to bring attention to counter narratives to the otherwise deleterious image portrayed of African American males. The history and plight of the African American male is included to provide a comprehensive understanding of the …

Coagulation Factor Xiiia: Biochemical Properties Underlying Physiological Function., Boris Anokhin

Electronic Theses and Dissertations

Factor XIIIA (FXIIIA) is a transglutaminase that crosslinks intra- and extracellular protein substrates. The oligomeric state of active FXIIIA remains controversial, and the present work commenced with addressing this issue. The results of size exclusion chromatography and analytical ultracentrifugation confirmed a dimeric state for zymogen and, for the first time, indicated a monomeric state for the active FXIIIA in solution. Comparing sedimentation properties of proteolytically and nonproteolytically activated FXIIIA suggested conformational and functional differences between the two forms. Those differences were further assessed in a series of catalytic activity studies. Kinetic analysis revealed affinity for the glutamine substrate was higher …

Public Policy And Strategies To Support Institutional And Technological Innovations In The New Water Economy: The Example Of Innovation Technology Clusters In Developing And Diffusing Water Technologies., Craig Francis Barham

Electronic Theses and Dissertations

A long list of water technologies has been central to human development throughout history. From the well in ancient times to desalination in the contemporary period, water technologies are needed to produce, distribute and treat water to support human life, industry, agriculture, and environmental health. As human development puts intense pressure on the planet's limited fresh water supplies, society is turning to increasingly innovative water technologies to close the supply-demand gap. The water economy represents a significant share of total economic output it its own right, while at the same time water directly or indirectly underpins all other economic activity. …

Furthering Understanding Of Forensic Units: A Detailed Examination Of Knoxville Police Department's Crime Scene Unit., Cassandra Christina Rausch

Electronic Theses and Dissertations

Throughout the past three decades, the criminal justice system has decidedly employed new technologies for the purposes of establishing guilt or innocence. Forensic science, with its synthesis of scientific methodology and investigative considerations of law enforcement, ushered in the development of DNA profiling and forever changed the process of crime scene investigation.This shift in focus also led to a shift in the individuals involved in investigation, producing the widespread formation of stand-alone crime scene units. Utilizing both civilian and sworn employees of a law enforcement agency, these units became responsible for the documentation, collection, and preservation of evidence that would …

The Emperor's New Clothes: How The New Atheists Are Reminding The Humanities Of Their Place And Purpose In Society., David Ira Buckner

Electronic Theses and Dissertations

This dissertation will examine the social and intellectual impact of the so-called “New Atheism” as evidenced by the writings and public careers of its four principal protagonists: evolutionary biologist Richard Dawkins, philosopher Daniel Dennett, journalist Christopher Hitchens, and neuroscientist Sam Harris. I will argue that the New Atheists together provide an account of reality philosophically superior to that of theism, including those superficially sophisticated variations espoused in the writings of scholars William Lane Craig, John Lennox, Allister McGrath, Alvin Plantinga, etc. Yet, even if this were not so, I would still contend that the accessible, informative, and provocative style of …

Computational Prediction, Characterization, And Methodology Development For Two-Dimensional Nanostructures: Phosphorene And Phosphide Binary Compounds., Congyan Zhang

Electronic Theses and Dissertations

In this thesis, a comprehensive computational simulation was carried out for predicting, characterizing, and applications of two-dimensional (2D) materials. The newly discovered GaP and InP layers were selected as an example to demonstrate how to explore new 2D materials using computational simulations. The performance of phosphorene as the anode material of Lithium-ion battery was discussed as the example of the application of 2D material. Furthermore, the semi-empirical Hamiltonian for phosphorous and lithium elements have been developed for our future work on the application of phosphorus and lithium-based systems. The novel 2D materials of GaP and InP binary compounds were found …

Impacts Of Ammonia And Temperature On Freshwater Snail Behavior And Physiology., Megan Christine Dewhatley

Electronic Theses and Dissertations

Gastropods are one of the most imperiled groups of animals in North America, yet there are major gaps in the literature pertaining to pollutants and climate change, and especially sublethal impacts. This dissertation assesses the effects of climate warming and unionized ammonia (NH₃), one of the most abundant water pollutants, on the behavior and physiology of two caenogastropod snails: fine-ridged elimia (Elimia semicarinata) and Shawnee rocksnails (Lithasia obovata) (Gastropoda: Neotaenioglossa: Pleuroceridae). Righting behavior, or the movement used by snails to turn themselves right-side-up, was used as the main endpoint; delays in this behavior compromise …

Lead And Crime: An Ecological Study Between Lead Contaminated Topsoil And Violent Crime., Brian Guinn

Electronic Theses and Dissertations

Lead is a known neurotoxicant. Human exposure to lead comes primarily through environmental exposures, including remnant lead paint, lead contaminated topsoil and lead contaminated water. Prenatal and early life lead exposure has been associated with numerous neurocognitive and neuropsychiatric disorders. This dissertation presents findings from an ecological study which evaluated the geospatial association between topsoil lead content and the incidence of FBI designated violent crime in Jefferson County, Kentucky. A total of 412 topsoil samples were collected along roadways (n=300) and from Louisville Metro Parks (n=112). Jefferson County crime data was obtained from the Louisville Metro Police Department – Crime …

The Role Of Aldehyde Dehygrogenase 2 In Liver Injury Caused By Vinyl Chloride And High-Fat Diet., Liya Chen

Electronic Theses and Dissertations

Background. Vinyl chloride (VC) is an abundant environmental contaminant that causes steatohepatitis at high exposure levels. We have shown previously that low concentrations of VC exacerbate high fat diet (HFD)-induced liver injury in mice. The mechanisms involved in the progression of liver injury caused by VC and HFD include oxidative stress, inflammation, metabolic and mitochondrial dysfunction. Mitochondrial aldehyde dehydrogenase 2 (ALDH2) serves as a key line of defense against most reactive aldehydes, including lipid aldehydes (e.g., 4-HNE) and chloroacetaldehyde (VC metabolite). We hypothesize that this defense may play a key role in the interaction between HFD and VC in fatty …

Landmine Detection Using Semi-Supervised Learning., Graham Reid

Electronic Theses and Dissertations

Landmine detection is imperative for the preservation of both military and civilian lives. While landmines are easy to place, they are relatively difficult to remove. The classic method of detecting landmines was by using metal-detectors. However, many present-day landmines are composed of little to no metal, necessitating the use of additional technologies. One of the most successful and widely employed technologies is Ground Penetrating Radar (GPR). In order to maximize efficiency of GPR-based landmine detection and minimize wasted effort caused by false alarms, intelligent detection methods such as machine learning are used. Many sophisticated algorithms are developed and employed to …

Particulate Hexavalent Chromium Does Not Induce Centrosome Amplification In Sperm Whale And Bowhead Whale Cells., Jennifer Haruka Toyoda

Electronic Theses and Dissertations

Hexavalent chromium [Cr(VI)] is a widespread environmental and occupational carcinogen. The mechanism of carcinogenesis remains poorly understood, but chromosome instability (CIN) is the dominant theory. How numerical CIN arises is unclear, but it correlates with centrosome amplification. Both phenotypes are hallmarks of cancers, early events in carcinogenesis, and have been shown to occur after Cr(VI) exposure to human skin and lung fibroblasts. In this study, we investigate numerical CIN and centrosome amplification in whale cells. Whales are our closest marine relatives, have long lifespans, and are exposed to environmental Cr(VI). Importantly, they have low cancer rates and cell culture studies …