Digital Commons Network^™

Virtual Unknotting Numbers For Families Of Virtual Torus Knots, Kaitlin R. Tademy

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

A virtual torus knot T(p,q,VC) sits in the intersection of the well-understood torus knot and the not-so-well-understood virtual knot, making it an intriguing object to study.

The unknotting number of a classical knot K is defined unambiguously. However, "the" unknotting number when K is a virtual knot is not as clear to define, since virtual knots have both classical and virtual crossings. We will define virtual unknotting number vu(K) as the minimum number of (classical) crossing changes required to unknot K. Under this definition of virtual unknotting, not all …

Investigation Of Faults In Air-Conditioning Systems In Commercial Buildings: Occurrence, Diagnostic Validation, And Energy Impacts, Yuxuan Chen

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

In commercial buildings, fault detection and diagnosis (FDD) tools have been developed for detecting and diagnosing faults in building systems, which can provide useful information regarding fault locations and potential causes of faults, so that building operators and facility staff can be notified in time and quickly respond as problems arise. Nowadays, there are many commercial FDD tools available in the market, and these tools have been widely adopted in large- and medium-scale commercial buildings in the United States. Several studies have demonstrated the energy saving potential with the use of FDD in commercial HVAC systems, and one critical aspect …

Integrating Water And Nitrogen Management For Sustainable Agriculture: Optimizing Resource Use Efficiency And Maximizing Crop Productivity, Jiaming Duan

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Advisors: Derek Heeren and Daran Rudnick Maize, accounting for over 95% of national grain production in the United States, is highly sensitive to water and nitrogen (N) inputs. Conventional agricultural practices often lead to excessive application, causing groundwater contamination through nitrate leaching. Therefore, there is a demand for integrating water and nitrogen management with innovative scheduling methods for sustainable agricultural development.

This dissertation first reviewed two decades of U.S.-based research, highlighting the optimal management of water and N to enhance yield, water use efficiency (WUE), and nitrogen use efficiency (NUE). Findings indicate that maintaining optimal levels of N and water …

"I Will Write Mad Stories": The Hysterical "I" In The Diaries Of George Eliot, Charlotte Forten Grimke, Virginia Woolf, And Sylvia Plath, Jaclyn Marie Swiderski

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation focuses on the long history of hysteria and the ways in which it has been used to denigrate and silence disabled women. Women diagnosed as hysterical, by either the medical establishment or the court of public opinion, are denied the right to generate knowledge about and for themselves – they are epistemologically disabled. The author argues that hysterical women have unique ways of looking at and understanding the world which push back against their epistemological disablement. In order to uncover some of this history of hysterical women, this dissertation uses the diaries of four “hysterical” women over the …

A Data-Driven Discovery System For Studying Extracellular Microrna Sorting And Rna-Protein Interactions, Sasan Azizian

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Interactions between microRNAs (miRNAs) and RNA-binding proteins (RBPs) are pivotal in miRNA-mediated sorting, yet the molecular mechanisms underlying these interactions remain largely understudied. Few miRNA-binding proteins have been verified, typically requiring extensive laboratory work. This study introduces DeepMiRBP, a novel hybrid deep learning model designed to predict microRNA-binding proteins. The model integrates Bidirectional Long Short-Term Memory (Bi-LSTM) networks with attention mechanisms, transfer learning, and cosine similarity to offer a robust computational approach for inferring miRNA-protein interactions.

DeepMiRBP is implemented through two distinct architectures. The first architecture employs a Y-shaped model that uses Bi-LSTM networks and transfer learning to extract contextual …

The Value Of Knowledge And Its Problems, Kevin Patton

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation answers the three value problems in epistemology. These three problems require an answer as to how knowledge is more valuable 1) than mere true belief, 2) any of the proper subsets of knowledge, and 3) in kind than that which falls short of knowledge. The methodology used to provide an answer to these problems relies on the arguments put forth in a rarely discussed paper from Ward Jones. In short, the Jonesian approach can be summed up as the view that epistemic axiology and analysis ought to be kept separate. The Jonesian framework instead looks outside of the …

Long Term Ultrasonic Monitoring And Machine Learning Investigation Of Micro-Crack Damaged Concrete, Yalei Tang

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The thermal modulation method is a recently developed nonlinear ultrasonic technique for evaluating material damage. This method utilizes thermal strain changes resulting from temperature variations to excite the nonlinear behavior of materials and modulate high-frequency ultrasonic waves within them. Its working principle suggests significant potential for application in large-scale concrete structures and in-situ monitoring of real structures. Despite numerous laboratory demonstrations of its effectiveness, several gaps remain before it can be applied to in-service large concrete structures.

This study investigates the potential of the thermal modulation technique for evaluating concrete structures in ambient conditions, addressing key uncertainties for practical implementation. …

Role Of The Malate Dehydrogenase-Citrate Synthase Metabolon In Metabolic Flux Regulation, Joy John Omini

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The TCA cycle enzymes- malate dehydrogenase (MDH) and citrate synthase (CS)- interact to transfer oxaloacetate from the active site of MDH to the active site of CS, through an electropositive channel. The MDH-CS metabolon is highly conserved across different domains of life, and it has been associated with many advantages. Some of these advantages include protecting oxaloacetate from competing enzymes like aspartate aminotransferase, allowing the thermodynamically unfavorable MDH forward reaction to occur and increasing the local concentration of oxaloacetate within the active site of CS. These advantages and conservativeness of the MDH-CS metabolon indicate that it is highly important to …

Teacher-Child Interaction Quality In Free Choice And Associations With Child Peer-Related Social Competence, Yuenjung Joo

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Children’s peer-related social skills in early childhood set the stage for school readiness, social competence, and lifelong well-being. Preschoolers spend most of their classroom time in free choice, offering substantial opportunities for learning experiences that facilitate peer interactions that support social development. Yet, little is known about how early childhood teachers can best optimize children’s social learning without disrupting the benefits of play during this time. The purpose of this study is to investigate how preschool teachers’ social support behaviors during free choice align with children’s social needs (i.e., fit of teacher-child social interaction) and the association between the fit …

Spreads And Transversals And Their Connection To Geproci Sets, Allison Joan Ganger

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Spreads of [set of prime numbers]³ over finite fields can yield geproci sets. We study the existence of transversals to such spreads, proving that spreads with two transversals exist for all finite fields, before further considering the groupoids coming from spreads when transversals do or do not exist. This is further considered for spreads of higher dimensional projective spaces. We also consider how certain spreads might generalize to characteristic zero and the connection to the previously known geproci sets coming from the root systems D₄ and F₄.

Advisor: Brian Harbourne

Perturbations Of Representations Of Cartan Inclusions, Catherine Zimmitti

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

A free semigroup algebra is the unital, weak operator topology closed algebra generated by a collection of Cuntz-Toeplitz isometries in B(H). Ken Davidson and David Pitts asked in [9] if a self-adjoint free semigroup algebra exists; Charles Read answered this question in [28] by constructing such an example, which Ken Davidson later simplified in [8]. The construction takes a standard representation of O₂ and multiplies it by a unitary operator in the diagonal MASA of the representation. This results in a new "perturbed" representation of O₂ generating a self-adjoint free semigroup algebra.

In this thesis, …

Emergent Phenomena In Ferroelectric-Dielectric And Ferroelectric-Graphene Heterostructures, Tianlin Li

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation explores the emergent phenomena in epitaxial ferroelectric oxide-based heterostructures, including the negative capacitance (NC) effect in ferroelectric-dielectric systems, ferroelectric gate imposed mobility limit in graphene field-effect transistors, and ferroelectric domain-induced graphene-superlattices.

We carry out a phenomenological study of the NC effect in PbZr_0.2Ti_0.8O₃/SrTiO₃ capacitors. The Landau free-energy profile predicts a critical thickness ratio for the ferroelectric-dielectric phase transition, consistent with the observed abrupt change in remnant polarization. A static NC state is observed in the low thickness ratio region, which is compromised by the emergence of multidomain in the moderate ratio …

Laser Surface Processing For Enhanced Adhesion Between Diamond Coatings And Metallic Substrates, Zhipeng Wu

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Application of diamond coatings on metallic substrates endows them with superior properties including mechanical robustness and corrosion resistance, rendering them highly adaptable for diverse industrial and technological applications. However, significant disparities in coefficients of thermal expansion (CTEs) result in pronounced residual stress near interfaces, causing delamination of the diamond coatings. Moreover, weak chemical bonding poses a concern for certain metallic substrates. Laser surface processing techniques show promise in enhancing adhesion by altering stress distribution and improving mechanical bonding. Therefore, the research efforts described in this dissertation mainly focus on femtosecond (fs) laser texturing for enhanced adhesion of diamond coatings on …

Pre-Service Teachers’ Noticing Of Students’ Mathematical Thinking When Planning, Teaching, And Reflecting On Lessons, Matthew Flores

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

A central aspect of reform-minded mathematical teaching is training and developing teachers' ability to notice vital aspects in the classroom and more specifically, students’ mathematical thinking. As there is an abundance of evidence and research that support the benefits for teachers to elicit and use students’ ideas and thinking during instruction, there are just as many challenges associated with developing and mastering this skill. Specially, teachers must learn to attend to important details of students’ thinking, interpret the meaning and understanding of students’ thinking, and finally, teachers must decide how to purposefully respond to the student in a manner that …

Dynamics Of Soybean Seed Protein And Oil Content With Depth In The Canopy, Hafith Furqoni

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Understanding the physiological basis of variation in seed composition is critical for optimizing soybean seed composition. Also, studying dry matter accumulation and nitrogen uptake, partitioning, and redistribution in soybeans is crucial due to its direct impact on seed yield levels and overall plant productivity. This study aimed to test the primary proxy influencing seed protein and oil content, which is their accumulation rate determined by the assimilate supply per seed. The second objective was to comprehensively understand soybean dry matter (DM) accumulation and nitrogen (N) uptake, partitioning, and removal patterns within the canopy. Field experiments were conducted using two soybean …

Three Essentials Of Private Property In Kant, Lauren Michelle Kashi

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

There are three principles of public right describing a civil condition and a citizenry that Kant offers: freedom, equality, and independence. I argue that these three principles offer further justification for both protection of property rights and enforcement of redistributive taxation than Kant’s Universal Law of Right and principles of property acquisition alone can. In a civil condition with legitimized laws protecting private property, citizens enjoy maximal freedom from interference, dependence, and inequality. Indeed, the purpose of the civil condition for Kant is to create such freedoms, which are made manifest by laws enforcing private ownership as well as redistribution …

The Effects Of Anchor Scheme On The Central And Peripheral Contributions To Performance Fatigability, Perceived Responses And Sensations, And Psychological Factors Following Sustained, Isometric Forearm Flexion Tasks To Failure, Robert Walker Smith

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The Effects of Anchor Scheme on the Central and Peripheral Contributions to Performance Fatigability, Perceived Responses and Sensations, and Psychological Factors Following Sustained, Isometric Forearm Flexion Tasks to Failure Robert W. Smith, Ph.D. University of Nebraska, 2024 Advisor: Terry J. Housh This study assessed time to task failure (TTF), performance fatigability (PF), neuromuscular responses, central and peripheral measures of fatigue, and perceived responses including sensations and psychological factors that contributed to task termination during sustained, isometric forearm flexion tasks anchored to ratings of perceived exertion (RPE) and the torque corresponding to RPE. Fifteen men (age = 21.5 ± 2.3 yrs; …

Applying Circuit Theory To Describe Changes In Structural Landscape Connectivity In Response To Wildfire, Christian Ross Nielsen

School of Natural Resources: Dissertations, Theses, and Student Research

Understanding and conserving ecological connectivity is critical to the preservation of vulnerable landscapes. Circuit theory, in which landscapes are imagined as circuit boards with varying resistances to the flow of current, is being increasingly used to model spatially explicit connectivity of landscapes and to inform land management and conservation decision-making. Utilizing continuous, quantitative estimates of percent cover by five land cover functional groups to create a conductance surface, this study expanded upon an established application of circuit theory that used the open-source software Circuitscape to model species-agnostic, omnidirectional connectivity. This model was automated using Python to create time-series connectivity maps …

Occurrence, Inputs, And Ecological Significance Of Antibiotics And Pharmaceuticals In Western Nebraska Streams, Katelyn F. Glause

School of Natural Resources: Dissertations, Theses, and Student Research

Few emerging environmental contaminants are as concerning as antibiotics. Human and animal health benefits greatly from the prudent use of antibiotics, yet we give little thought to environmental release of these biologically active compounds. Environmental occurrence of these and other pharmaceutical compounds must be measured in different environmental compartments such as municipal wastewater and in the vicinity of large animal feeding operations to understand potential effects. This study reports the results of a monitoring study in western Nebraska, with a large population of livestock and smaller but more concentrated population of humans, comparing the relative environmental concentrations and loading from …

Analysis Of Drought-Flood Abrupt Alternation Events And Their Impacts In Kenya, Betty Makena

School of Natural Resources: Dissertations, Theses, and Student Research

Drought-Flood Abrupt Alternation (DFAA) is a compound disaster event that refers to the abrupt shift of extreme drought events to extreme floods resulting in exacerbated impacts on already vulnerable communities and hindering their coping abilities. This study aimed to analyze drought-flood abrupt alternation events and their impacts in Kenya. The first chapter aimed to understand historical drought events in the Greater Horn of Africa and their impacts, while drawing comparisons with the recent 2020-2022 drought period, referred to as the ‘triple dip La Niña’. Datasets used in this study include the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS), Normalized …

Remotely Sensed Early Warning Of Algal Blooms In An Eastern Nebraska Reservoir: A Comparison Of Temporal And Spatial Indicators, Mercy Kipenda

School of Natural Resources: Dissertations, Theses, and Student Research

Cyanobacterial harmful algal blooms (CyanoHABs) detrimentally affect human, animal, and ecosystem health. Remotely sensed early warning systems for cyanoHABs in inland lakes could contribute to more proactive water quality monitoring and help mitigate negative impacts. Advances in freely available remote sensing imagery, with finer spatial, temporal, and spectral resolutions, present new opportunities for the development and comparative analysis of methods to detect sudden deterioration in lake water quality. In this thesis, I compared and tested for temporal and spatial early warning signals of cyanoHABs in field-based and remotely sensed datasets from 2019 to 2023 in Pawnee Lake in southeast Nebraska, …

Impacts Of Invasive Carp And Their Population Dynamics On Fish Communities In The Missouri River, Joshua F. Kocik

School of Natural Resources: Dissertations, Theses, and Student Research

Invasive Carp species: Silver Carp Hypophthalmichthys molitrix, Bighead Carp Hypophthalmichthys nobilis, Grass Carp Ctenopharyngodon idella, and Black Carp Mylopharyngodon piceus have both potential and realized abilities to negatively impact native species. Specifically, Bighead Carp and Silver Carp as filter feeders have been theorized to be detrimental not only to adult filter-feeding species, but to many fish which rely on plankton and algae in their early-life stages. The impact of Invasive Carp on the overall fish community remains underexplored. The fish communities below Gavins Point Dam (Invasive Carp present) and Fort Randall Dam (Invasive Carp absent) afford the …

Spatiotemporal Plasticity In Reproductive Readiness And Recruitment Of Ichthyoplankton Of Invasive Silver Carp Along A Western Invasion Front, Jessi L. Urichich

School of Natural Resources: Dissertations, Theses, and Student Research

Individuals of invasive species at the edge of their invasion distribution may exhibit enhanced reproductive capacity and phenotypic plasticity leading to accelerated range expansion. Environmental conditions in highly fluctuating environments at distribution edges may either promote or hinder such reproductive readiness and phenotypic plasticity. Dynamic habitat conditions and periodic disturbances experienced in prairie streams, such as drought (e.g., low-flow, high water temperatures), may potentially reduce suitable spawning environments and ichthyoplankton recruitment of invasive Silver Carp, potentially slowing range expansion or enabling management strategies that reduce abundance in the absence of a reproducing population. Female Silver Carp batch fecundity, Gonadosomatic Index …

Assessing, Restoring, And Centering Social–Ecological Relationships For Advancing Social–Ecological Resilience In The Northern Great Plains Grasslands, Katia Pilar Carranza Bernal

School of Natural Resources: Dissertations, Theses, and Student Research

The Northern Great Plains grasslands are social-ecological systems that were shaped by evolutionary and Indigenous social-ecological relationships. European colonization disrupted many of these interactions, including the coupling of fire and grazing, and degraded social-ecological resilience, shifting these grasslands to a new state. For those reasons, my research focused on assessing, restoring, and centering evolutionary and Indigenous social-ecological relationships for advancing social-ecological resilience in the Northern Great Plains grasslands. I first performed a study in the Nebraska Sandhillls assessing the potential of patch-burn grazing to support grassland resilience by comparing its effects to those of rotational grazing. Through vegetation and bird …

Sensitivity Of Present And Future Seasonal Precipitation Over Central United States To The Representation Of Rocky Mountain Topography, Ranasinghe Disanayakalage Sherly Shelton Ranathunga

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Precipitation change across the Central United States (USA) is of great interest to the research community. Studies using global climate simulations suggest that the “100^th-Meridian”, which separates the “dry west” from the “moist east” will shift to the east as the climate responds to future emissions pathways. However, these simulations are run at relatively coarse resolutions, which do not accurately represent topography. Here, we perform regional simulations using the Weather Research and Forecasting (WRF) model to explore the sensitivity of present and future precipitation patterns across the central USA to the representation of the Rocky Mountains (RM). We …

We're Swarming Again! Swarming, Collectivity, And Trope: The Case Of Extinction Rebellion, Tyler J. Behymer

Department of Communication Studies: Dissertations, Theses, and Student Research

This thesis explores the rhetoric of the eco-movement Extinction Rebellion, focusing on the use of swarming and nature tropes to mobilize collective action and revivify contemporary notions of collectivity. Drawing on rhetoric of social movement scholarship, cultural studies, and psychoanalysis, this essay theorizes swarming as a tropological economy that expands the conditions of propriety in the context of collectivity. Through an analysis of Extinction Rebellion’s discourse, this study demonstrates how the naturalization of swarming tropes works in various ways to rewild conventional political discourse, galvanize disruptive collective assembly, and challenge green neoliberalism.

Advisor: Casey Ryan Kelly

Integration Of Matlab And Machine Learning To Accelerate Evaluation Of Biological Activity In Agricultural Soils And Promote Soil Health Improvement Goals, Andrew Stiven Ortiz Balsero

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Traditionally, assessments of soil biological activity have been confined to laboratory settings, creating a disconnect with practical in-field methods. To bridge this gap, cotton fabric degradation has been used to illustrate soil microbial activity under different management practices. While effective, these demonstrations are subjective and labor-intensive.

Researchers have explored using image processing software like ImageJ and Adobe Photoshop to streamline this process. Although these tools accurately quantified fabric degradation under varying soil conditions, the methods remained labor-intensive and complex. Consequently, these methods were still not ideal for on-farm use by agricultural practitioners.

To further address labor and complexity limitations, the …

The Use Of Fourier-Transformed Infrared Spectroscopy With An Infrared Biotyper To Establish Classifiers For Major Serogroups Of Moraxella Bovis Based On Spectral Profiles, Jordyn Bailey Schommer

Honors Program: Senior Projects (Public)

A classifier tool was created to identify major serogroups of Moraxella bovis based on spectral profiles collected from bacterial cells through the use of Fourier transformed infrared spectroscopy. M. bovis strains were selected from a group of previously sequenced and genotyped isolates, which provided the pilin sequence type for each isolate. The obtained spectroscopic profiles were analyzed through artificial neural networks to create a classifier tool that could identify the PilA type for unknown strains. Once a sufficient spectral library was obtained, the isolates were split into a training and a validation group, each containing spectra from isolates of five …

"Huddled Masses:" The Immigration Act Of 1917 In Habeas Corpus, Chikamso Chijioke

Digital Legal Research Lab

Research poster titled "Huddled Masses:" The Immigration Act of 1917 in Habeas Corpus; presented via the Digital Legal Research Lab NSF REU Site, University of Nebraska–Lincoln, August 2024.

Introduction

Dr. Jagodinsky's Petitioning for Freedom is a collection of habeas corpus petitions in the American West and examines marginalized peoples’ use of habeas to challenge detention. This project explores the role of the Immigration Act of 1917 in these cases. The Immigration Act of 1917, passed due to xenophobic tensions surrounding WWI, restricted immigration of people from Asia and the Pacific while implementing an English literacy test for those over 16 …

Candida Albicans Farnesol Synthesis And Secretion, Daniel J. Gutzmann

School of Biological Sciences: Dissertations, Theses, and Student Research

Candida albicans is a polymorphic fungus and opportunistic commensal found primarily in the gastrointestinal and skin of healthy individuals. Several barriers prevent C. albicans from causing disease including a healthy immune system and microbiome. When these barriers become comprised, C. albicans can transition to a pathogen and disseminate through the intestinal mucosa leading to life-threatening bloodstream and invasive infections with mortality rates of up to 64%. Morphogenic plasticity is key to this transition and impacts virulence, adaptation to different host environments, and evasion of host immune responses. One regulator of morphogenesis is farnesol. Farnesol is a secondary metabolite of …