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Ferroelectricity And Multiferroicity In Ultrathin Films Of Unconventional Transition Metal Oxide, Xin Li

Department of Physics and Astronomy: Dissertations, Theses, and Student Research

Ferroic orders of transition metal oxides, such as ferroelectricity and ferromagnetism, are determined by the intercoupling between spin, charge, lattice. Consequently, ferroic epitaxial thin films have attracted wide interest due to the profuse novel phenomena and the great application potentials for modern electronics. However, the mainstream of the study for transition metal oxides has focused on perovskite structure, limiting the understanding and discovery of novel phenomena associate with ferroic orders. In this thesis, the epitaxial films of hexagonal rare-earth ferrites (h-RFeO₃) and fluorite-structure hafnia oxide (HfO₂) are studied comprehensively, providing new experimental and theoretic …

Assessment Of Estuarine Respiration And Benthic Nutrient Fluxes In Mississippi Sound, Nur Pasha Sufian

Master's Theses

This study quantified seasonal and spatial variability of both water column and benthic respiration rates as well as benthic nutrient fluxes along the Mississippi Sound. Respiration was measured in recirculating incubation chambers using Firesting optical DO sensors (PyroScience GmbH), and changes in nutrient concentrations were assessed. Mean water column respiration rates ranged from 0.35 and 2.76 µM O₂ hr⁻¹, with the lowest rates in the winter and the highest in the summer while detectable nutrient concentrations (ammonium, (NH₄⁺), and soluble reactive phosphate (PO₄³⁻)) showed only slight decreases (< 1 µM) over all seasons. Sediment incubation chambers consistently had much greater oxygen declines than the water incubations and showed seasonal trends with the highest mean respiration rates measured in the summer and the lowest mean in the winter, with a range from 107.4 to 1514.9 µmol O₂ m⁻² hr⁻¹ (2.6 to 36.3 mmol O₂ m⁻² d⁻¹). Sediment incubations consistently showed increases in NH₄⁺ concentrations in the overlying water, resulting in calculated NH₄⁺ benthic flux rates of 0.73 to 379.01 µM N m⁻² hr⁻¹ with the lowest rates in the winter and highest rates in the summer. Although PO₄³⁻ concentrations were often below detection in cooler seasons, PO₄³⁻ flux also peaked during the summer (< 28.8 µmol P m⁻² hr⁻¹). In this study, temperature was a key regulator for estuarine respiration and benthic nutrient flux rates, and these rates were positively correlated with porewater nutrient concentrations and sedimentary organic matter. These findings illustrate that benthic respiration can contribute to water column hypoxia and that sediments serve as a source of nutrients to the water column. Overall, these findings provide us with valuable insight about the seasonal coupling of oxygen demand and nutrient flux in the Mississippi Sound and provide valuable baseline data for future biogeochemical modelling of hypoxia, eutrophication, and productivity.

Plant Nutrient Interactions In High-Yielding Soybean Environments, Victoria Inklman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Plant nutrient demands and limitations are usually studied individually by nutrient. Here, we investigated how nitrogen (N) limitation in high-yielding soybean environments affects the uptake, removal, and residual of other plant macro- and micronutrients. The objective of this study was to quantify the uptake, removal, and residual levels of soybean macro- and micronutrients under N-limited conditions and to identify nutrient priorities for high-yielding soybean systems. Aboveground plant samples at physiological maturity were collected in 19 high-yielding soybean fields with N limitation across the state of Nebraska. Reference plots with ample N supply were included within each field to compare macro- …

Interpolation In Weighted Projective Spaces, Shahriyar Roshan Zamir

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

Over an algebraically closed field, the double point interpolation problem asks for the vector space dimension of the projective hypersurfaces of degree $d$ singular at a given set of points.

After being open for 90 years, a series of papers by J. Alexander and A. Hirschowitz in 1992–1995 settled this question in what is referred to as the Alexander-Hirschowitz theorem. In this thesis, we use commutative algebra to prove analogous statements in the weighted projective space, a natural generalization of the projective space.

A main contribution of this work is the careful adaption of several classical algebro-geometric techniques to the …

Don't Settle For Less: Incorporating Postcolonial And Settler Colonial Perspectives Into The Sociological Canon, Eli Xavier Ornelas

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

For decades now, post-/de-/settler-/ and anticolonial scholars have advanced the argument that sociology has largely failed to incorporate critical insights from theories of empire into the sociological canon. In this dissertation, I argue that introduction to sociology textbooks offer an important vantage point from which to assess conventional sociological knowledge as textbooks are often thought to be “reflections of the discipline.” I analyze the social theory and race chapters of 21 of the most often used introduction to sociology textbooks in the United States to investigate two chapters where insights from theories of empire would be present if indeed incorporated: …

Applications Of Preclinical Magnetic Resonance Imaging In The Treatment Of Traumatic Brain Injury And Understanding Carotid Artery Atherosclerosis, Evan Timothy Curtis

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

Advances in magnetic resonance imaging (MRI) provide the opportunity to investigate research questions that have been left unanswered. In the cases of traumatic brain injury (TBI) and carotid artery atherosclerosis, MRI is a resource for non-invasively viewing the phenomena taking place. Additionally, potential interventions and treatments can be observed without harm to the subject. This dissertation expands the understanding of two preclinical applications of MRI: traumatic brain injury and carotid artery atherosclerosis in mouse models.

TBI is a leading cause of death and disability for individuals between 15–45 years of age and effective pharmaceutical interventions for treating the secondary damage …

Mass Effects On Energy Transfer Paths In Nonlinear Vibrating Systems, Manal Mustafa

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

This dissertation examines the role of mass in nonlinear systems, uncovering its role in enabling passive energy redistribution and robust vibration control in both idealized and real-world structures. Focusing on a strongly nonlinear two-degree-of-freedom system, it investigates how changes in mass ratio influence the dynamics of energy transfer, nonlinear normal modes (NNMs), and dissipation behavior.

A number of significant contributions are introduced in this work beginning with the introduction of the frequency-energy-peaks (FE-pks) plot, a novel tool that visualizes how energy flows through the system, revealing transient resonance orbits, internal resonance effects, and effectively capturing the different nonlinear phenomena with …

Study Of Ai Applications In Biomedical Data Acquisition, Communication, And Analysis: Cest Mri Acceleration And Ecg Transmissions, Adarsha Bhattarai

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

This dissertation investigates the application of artificial intelligence in biomedical data acquisition, communication, and analysis to advance neurological research and to enable the early detection of cardiovascular conditions. Despite significant advances in imaging and physiological modalities, challenges persist. Imaging modalities, such as the chemical exchange saturation transfer magnetic resonance imaging (CEST MRI) technique are challenged by a prolonged data acquisition time and high operational costs. In addition, physiological modalities such as electrocardiogram (ECG) sensors face constraints in providing uninterrupted signal monitoring which is crucial for the timely detection of premature cardiac abnormalities. The primary goal of this work is to …

The Career Resilience Of Women Of Color Amidst Intersectional Racism-Sexism In The Us: A Consensual Qualitative Study, Hannah Ahmad Ridzuan

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

Women of color have historically and presently experienced both sexism and racism on interpersonal, institutional, and cultural levels (Sue et al., 2007). While discrimination based on racial-ethnic and gender identities has by far the most extensive literature base (Duffy et al., 2016), literature on the development of women of color career resilience is not as expansive. Informed by the Psychology of Working Theory (PWT) (Blustein, 2006; Duffy et al., 2016), the intersectionality framework (Crenshaw, 1989; Collins et al., 2021), and critical consciousness (Freire, 1971; Quiñones-Rosado, 2020), this consensual qualitative research (CQR; Hill, 2006) explored how women of color in the …

On Kernels And Antiderivatives Of Nonlocal Derivatives, Alex John Heitzman

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

Nonlocal operators are mathematical operators taking functions to other functions f → Df , where to evaluate the operator Df at a point x, one must know the value of f in some region around x, and that region cannot be arbitrarily small. Nonlocal derivatives are like derivatives in that they measure the deviation of a function f(z) from f(x) when z is close to x. In this thesis, we will study nonlocal operators of the form

D_kf(x) = [integral]_Ω [f(x) …

Flooding: Risk Assessment And Its Interaction With Population & Environmental Health, Shivendra Srivastava

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

Flood events have significant implications for both population and environmental health. This dissertation aims to explore flood risk and its interaction with humans and the environment. The key questions addressed in this dissertation include improving the existing flood risk framework to better assess population vulnerability and associated risk. Additionally, it explores how interactions among risk components vary across spatial scales and regions, and how these variations influence overall flood risk. The dissertation also investigates how to design a vulnerability component specific to flooding within flood risk estimation. Finally, it answers whether flood-specific vulnerability differs for a population compared to vulnerability …

From Classroom To Content Creator: Leadership Practices And Identities Of Female Science Teachers On Tiktok, Rachel M. Benzoni

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

This qualitative multiple case study investigates how four secondary science teachers use TikTok to advocate for science education and how content creation shapes their professional identities as leaders. Using interviews and video content with a framework integrating constructivist leadership, Leader Identity Construction Theory (LICT), and the Social Change Model (SCM), findings show participants enacted leadership outside formal roles through distributed and relational practices leveraging social media's affordances. Five themes emerged from the analysis: (1) Reconceptualizing Teacher Leadership on Social Media, (2) Leadership Through Equity-Driven Practice, (3) Constructing and Leading in Online Professional Learning Communities, (4) Forming and Negotiating Identities in …

“Self-Compassion Has To Be The Heartbeat Of How I Move Through Life”: A Mixed Methods Study Of Family Caregiver Emotional Well-Being, Sarah O. Rasby

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

Often referred to as “hidden patients,” family caregivers endure numerous physical, emotional, psychological, and social hardships due to the demands of caregiving, which often results in their own needs going unmet. With the projected 61.3 million of the baby boomer generation entering the long-term care phase by 2029 along with a mass shortage of professional caregivers post-pandemic, more and more family members are expected to fill in for the role of care without sufficient access to support services (Pollard & Scommegna, 2014; Smith & Chang, 2016). An exploratory, mixed-methods study using a three-group intervention design was utilized to investigate the …

Honoring Childhood Agency In Developmental Research: Best Practices, Applications, And Insights, Amanda N. Howery, Olivia J. Lashley, Hanna R. Wright, Julia L. Williams, Olivia K. Nomura, Eline Lenne, Elizabeth K. Wood, Hanna C. Gustafsson, Elinor L. Sullivan

School of Social Work Faculty Publications and Presentations

Pediatric research requires caregivers to provide informed consent on behalf of their children. While not a formal requirement for children under the age of seven, it is important to involve child participants in the assent and decision-making processes in developmentally appropriate ways. This is especially important in longitudinal research, where the extent to which a developing child understands study tasks evolves over time. Although there is consensus that assent procedures are important and necessary, limited resources synthesizing strategies for pediatric researchers to encourage positive and respectful research experiences for young children exist. We describe methods used in an ongoing longitudinal …

How Developers Use Type-System Related Programming Language Features, Samuel W. Flint

School of Computing: Dissertations, Theses, and Student Research

Optional type annotations are a popular feature of programming languages that allow developers to omit explicit type information in code while, in some cases, retaining many of the benefits of static typing, such as in-code documentation, improved detection of type errors, or enforcement of code properties. However, how developers use and understand optional type annotations is not clear. The focus of this dissertation is to understand the use and comprehension of optional type annotations.

Optional type annotations are examined through four lenses: first, by examining the evolution of usage in a statically typed programming language (Kotlin, the default language for …

The Earliest University Of Nebraska Graduate Degrees, 1886-1909, Mark A. Griep

Mark A. Griep Publications

This list of the earliest graduate degrees awarded by the University of Nebraska (NU) in Lincoln was assembled to learn about the university’s research activity that preceded its admission to the prestigious Association of American Universities (AAU) in 1909.

Bulloch County National Register Of Historic Places Collection, Zach S. Henderson Library Special Collections

Finding Aids

Spanning 1970 to 1997, the collection contains materials regarding the application process for various Bulloch County properties to the National Register of Historic Places. Materials include official application paperwork, along with correspondence between various officials and property owners regarding processing, status updates, or requests for more information. Photographs of properties and supplemental documents such as genealogical records, newspaper clippings, and written narratives surrounding the development of the properties are also included.

Find this collection in the libraries' catalog.

Stabilization Of Cr³⁺ Using Iron Rich Slag-Derived Phosphate Cement: An Integrated Solution For Heavy Metals And Hazardous Solid Wastes, Ting Huang, Hongyan Ma, Zhongqiu Luo, Xintao Zhou, Zhengqing He, Peiwen Lv, Xiunan Cai, Pingyan Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A novel iron-based phosphate cement (IPC), derived from iron-rich smelting slag (ISS), was developed as a sustainable and efficient binder for the stabilization/solidification of trivalent chromium (Cr³⁺). The mechanical properties, hydration behavior, microstructure, leaching toxicity, chromium chemical forms, and environmental safety of chromium-stabilized iron phosphate cement (CIPC) were thoroughly evaluated. The results showed that, with a mass ratio of ISS to ammonium dihydrogen phosphate (ADP) of 2.0, and even with the addition of 20 % chromium nitrate nonahydrate (CN), the compressive strength of CIPC reached 4.2 MPa after curing for 28 d. Furthermore, chromium leaching was well below …

Coupling Effect Of Abrasion And Erosion On Ultrahigh-Performance Seawater-Sea Sand Concrete, Dawei Ding, Wei Zhang, Lanqin Wang, Hongyan Ma, Biqin Dong, Song Han, Hongjian Xu, Dongshuai Hou

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Preparing ultrahigh-performance seawater-sea sand concrete (UHPSSC) to mitigate the scarcity of freshwater and river sand resources has generated considerable recent research interest. However, the deterioration mechanisms of UHPSSC under the effect of abrasion and erosion remain unstudied. In this paper, the underwater steel ball method was conducted to evaluate the impact of seawater, sea sand, steel fiber, and seawater abrasion on the abrasion resistance of UHPSSC. Then the stress erosion models of calcium-silicate-hydrate (C-S-H) were constructed to investigate the degradation mechanisms of UHPSSC under the effect of external stress and seawater erosion. The results show that the application of seawater …

Msw Portfolio, Krystal F. Youngs

Graduate Student Portfolios, Professional Papers, and Capstone Projects

No abstract provided.

Promoting Metacognitive Awareness Through Exploratory Learning., Ryan J. Patrick

Electronic Theses and Dissertations

Exploratory learning engages learners in novel problem solving before direct instruction. This process is designed to lead learners to experience productive failure. Productive failure, however, has been shown to benefit learners by improving the recognition of knowledge gaps, relevant problem features, and deep structures. This allows learners to better attend to relevant information during the subsequent instruction and improves conceptual understanding. This dissertation investigates the role of metacognitive awareness during exploratory learning, in attempt to identify additional metacognitive mechanisms that support exploratory learning. Two experiments tested the theory that exploratory learning promotes metacognitive awareness in exploratory learning. Groups in both …

Opportunistic Short-Term Water Uptake Dynamics By Subalpine Trees Observed Via In Situ Water Isotope Measurements, Matthias Sprenger, Stefan Seeger, Max Berkelhammer, Nathaniel A. Bogie, Raymond J. Hess, Wendy S. Brown, Sylvain Kuppel, James Knighton

Faculty Research, Scholarly, and Creative Activity

Variations in tree water sources are important to understand in semi-arid ecosystems because climatic shifts towards lower snowpack and increased drought affect water availability in subalpine forests of the western US. Here, we use daily in situ measurements of stable isotopes (²H & ¹⁸O) in soil and tree stem water, soil matric potential and sap flow to study tree water uptake dynamics. We instrumented three soil profiles down to 90 cm, as well as three aspen and engelmann spruce trees near Gothic, Colorado, in the East River watershed. We observed the fate of natural isotopic variations in …

Queer Convergence: Figurative Abstraction In Contemporary Art., Vincent Young

Electronic Theses and Dissertations

This thesis is an exhibition text for the exhibition of the same name held in Schneider Hall Galleries from May 15 to August 21st, 2025. This exhibition explores the work of three contemporary artists – Joshua Jenkins, Drew Scanlon, and Lalana Fedorschak – and analyzes their artwork through the lens of Queer Convergence. Queer Convergence is an exploration of abstracted images of bodies and how we can read these bodies through a queer lens, arguing that the visual language of bodily overlap, melding, and transformation shows the physical form as a site of continual change shaped by shared experience and …

Ecosystem Services Of Urban Green Spaces In Louisville, Ky., Julia Kachanova

Electronic Theses and Dissertations

Accelerating urbanization poses critical challenges to urban green spaces (UGS), vital for ecological balance and human health. Rapid development often results in fragmented habitats, biodiversity loss, and diminished ecosystem service delivery. There is an urgent need to explore and evaluate novel strategies capable of enhancing urban resilience, such as implementing urban orchards, and managing existing parks and gardens in sustainable ways. This dissertation explores how different forms of urban green spaces (UGS) contribute to the provision and maintenance of critical ecosystem services that support human well-being and urban biodiversity. By analyzing UGS impact on ecosystem service provisioning and long-term sustainability, …

Teaching Out Of The Closet: A Qualitative Study To Examine How Queer Educators Navigate Their Professional Work Environments., Brent Braun

Electronic Theses and Dissertations

Queer educators across the nation have faced an onslaught of issues in recent years as they maneuver working in the heteronormative environments of public schools. With the passing of Senate Bill 150 in the Commonwealth of Kentucky in 2023, Kentucky educators became a part of the growing group of educators having to silence themselves within their classroom environments in order to protect their professional careers. This study sought to examine the ways in which queer educators navigate their professional environments in making decisions to either disclose or keep private their identity within the queer community. Semi-structured interviews were completed with …

Remotely-Sensed Urbanization And Local Perceptions Of Change From 1985-2024 In Southern Indiana., Marlea Ferber

Electronic Theses and Dissertations

This study is focused on the land cover change of non-built land cover being transformed into built land cover in two counties in Southern Indiana using mixed methods. Remote sensing was used to identify and quantify land cover change, and interviews were used to understand local perceptions of the physical land cover changes. The study area is situated along the rural-urban continuum with Louisville, Kentucky across the Ohio River. It is important to quantify the amount of land change conversion to built settlement as patterns and rate of urbanization help us to better manage transitions along the rural-urban continuum, but …

An Exploration Of Lgbtq+ Runner Motivation And Constraints., Michael Clemons

Electronic Theses and Dissertations

Running offers extensive benefits beyond physical fitness, encompassing mental, emotional, and social advantages. However, LGBTQ+ individuals face unique challenges in participating in the running community, which remains predominantly White, cisgender, and heterosexual. With the LGBTQ+ population in the U.S. growing, there is a need to understand their motivations and barriers to participation in running events and training groups. This study explores these motivations using self-determination theory, comparing LGBTQ+ and non-LGBTQ+ runners to identify differences in driving factors such as social connectivity, self-esteem, and competition. Additionally, it examines barriers LGBTQ+ runners face, ranging from structural obstacles to intrapersonal challenges, and how …

Predictor-Informed Bayesian Nonparametric Clustering., Md Yasin Ali Parh

Electronic Theses and Dissertations

In this dissertation, we performed clustering of observations such that the cluster membership is influenced by a set of predictors. To that end, we employ the Bayesian nonparametric Common Atom Model (CAM), which is a nested clustering algorithm that utilizes a (fixed) group membership for each observation to encourage more similar clustering of members of the same group. CAM operates by assuming each group has its own vector of cluster probabilities, which are themselves clustered to allow similar clustering for some groups. We extend this approach by treating the group membership as an unknown latent variable determined as a flexible …

Optimization And Simulation Models For Integrating Social Determinants In Assessing And Optimizing The Accessibility And Efficiency Of Community Pharmacy Networks., Md Morshedul Alam

Electronic Theses and Dissertations

Community pharmacies are essential components of the healthcare system, serving not only as points of medication access but also as providers of health consultations and preventive care. However, disparities in pharmacy access persist due to a combination of geographic, socioeconomic, and behavioral factors. This dissertation develops a comprehensive methodological framework to evaluate and improve accessibility to community pharmacies, integrating optimization, choice modeling, and discrete event simulation. First, we develop an Optimal Community-Pharmacy Assignment (OCPA) model to quantify geographic accessibility across a regional population network. The model minimizes risk-adjusted travel distances between population centers and pharmacies, incorporating social determinants of health …

Synthetic And Pharmacological Diversity Of Nitrogen-Containing Heterocycles., Shramana Ghosh

Electronic Theses and Dissertations

Nitrogen-containing heterocycles are a foundational class of compounds in organic chemistry, playing critical roles in pharmaceuticals, agrochemicals, and natural products due to their structural diversity and biological relevance. Among them, isoindolinones are notable for their wide range of pharmacological activities. Structurally, isoindolinones possess a benzylic methylene group adjacent to the nitrogen atom, which allows for selective oxidative transformations to yield phthalimide derivatives, well-known intermediates in synthetic, pharmaceutical, and materials chemistry. Although phthalimide is traditionally employed as a protecting group for amines via the Gabriel synthesis, isoindolinone offers a valuable alternative. Through a modified Gabriel-like approach, isoindolinones can serve as more …