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Performance Fatigability And Neuromuscular Responses During And After One Set Of Forearm Flexion Muscle Actions To Failure At 30% Versus 70% One-Repetition Maximum In Men And Women, Tyler Joseph Neltner

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

Previous studies have examined sex differences in performance fatigability during isometric, isokinetic and controlled dynamic constant external resistance (DCER) fatiguing tasks (FT), however, whether those sex differences remain during maximal intended velocity (MIV) DCER muscle actions remains unclear. The purpose of this study was to examine the sex-related differences in the time course of fatigue, neuromuscular responses, and coactivation from the ipsilateral and contralateral limbs during MIV DCER muscle actions to failure at low versus high relative loads, as well as performance fatigability from pre- to post-testing. Twenty-seven college-aged men (n = 14) and women (n = 13) …

Exploring Producers' Willingness To Pay For Ecosystem Services: Three Essays On Soil Health, Location Preferences, And Cover Crop Adoption, Kaouter Essakkat

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

This dissertation comprises three essays: one assessing Midwest producers' willingness-to-pay (WTP) for soil health-enhancing ecosystem services (ES), another examining the impact of policy implementation locations on WTP, and a third identifying factors influencing producers' adoption of cover crops (CC).

The first essay pioneers the understanding of agricultural producers’ valuation of soil health-associated ES amid growing concerns of soil degradation due to agricultural intensification. Using a discrete choice experiment, this study assesses producers’ WTP for a policy that incentivizes ES provision, specifically improved water quality, carbon sequestration, and enhanced crop yield. Surveying producers across Iowa, Kansas, and Nebraska, our results show …

Laser 3d Printing Of Diamond-Based Composite Materials For Thermal Management Applications, Nada Kraiem

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

With the trend towards miniaturization of electrical equipment and the constant increase in power density in semiconductor devices, efficient heat management has become a major concern for researchers. Indeed, this technological evolution imposes increasingly strict constraints in terms of thermal dissipation, necessitating innovative solutions to ensure better durability and reliability of components. In this context, the use of composite materials offering high thermal conductivity (TC) and low coefficient of thermal expansion (CTE) compared to pure metals has become essential to address overheating issues in electronic components.

The utilization of advanced materials such as diamond (D), with exceptional TC and hardness …

Population Demography, Occupancy, And Connectivity Of Invasive Bigheaded Carp In The Platte River, Nebraska And Its Tributaries, Blake W. Logan

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

Silver Carp Hypophthalmichthys molitrix and Bighead Carp H. nobilis, collectively referred to as bigheaded carp, are invasive species in the United States of America that have expanded their range throughout the Missouri River basin in the last three decades. It may be desirable to develop management plans directed at the monitoring, control, or removal of bigheaded carp within the Missouri River basin. However, a knowledge gap exists regarding bigheaded carp ecology in Missouri River tributaries, which may be important for the development of management plans. As such, this study characterized bigheaded carp population demographics, occupancy, and connectivity in …

Virtual Fencing In Livestock Management: Effects On Beef Cattle Stress And Enhancing Wildlife Conservation, Kaitlyn E. Dozler

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

I examined the effects of virtual fencing on beef cattle stress and how implementing the technology can aid wildlife habitat conservation at the University of Nebraska Gudmundsen Sandhills laboratory (GSL) near Whitman, NE. First, I examined how virtual fencing influences acute heart rate changes in beef cattle fitted with the virtual fencing collars. No significant difference in the average heart rate of a cow (P > 0.05) was observed between the 30 min control and virtual fenced periods for both trial dates. Second, I examined the influence of topography on wildlife species richness and presence at GSL using wildlife camera …

Spatial Ecology Of Mountain Lions Throughout Their Distribution In California, Kyle D. Dougherty

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

Mountain lions (Puma concolor) have been studied extensively throughout their wide geographic distribution in the Western Hemisphere, but most research has been conducted at relatively small spatial scales. We used GPS telemetry data contributed by researchers in 16 study areas throughout California to advance understanding of mountain lion spatial ecology. First, we investigated multi-scale resource selection of mountain lions relative to spatially varying risk of intentional human-caused mortality associated with livestock depredation management. We show that individuals that proactively avoided mortality risk when selecting home ranges were able to relax their avoidance of risk when making resource selection …

Hybridization Between The Rare Gray-Headed Chickadee And The Abundant Boreal Chickadee In The Midst Of Shifting Climate, Matthew R. Armstrong

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

As species respond to changing climate, distributions and abundances may shift and alter species interactions. Hybridization, a relatively widespread phenomenon becoming more common with climate change, can have beneficial and detrimental effects on population growth rates and genetic integrity. Beneficial effects due to the introduction of advantageous alleles and increased genetic diversity may result from hybridization. Species may also accrue fitness costs associated with changing climates if mismatches occur between environmental variables and phenotypes. The gray-headed chickadee, Poecile cinctus lathami, is an extremely rare songbird that has experienced marked declines in recent decades within its restricted distribution in Alaska …

My Ai Companion: An Examination Of The Removal Of Erotic Role Play From Replika Through User Discussion On Reddit, Chelsee M. Allen

Department of Sociology: Dissertations, Theses, and Student Research

The development of artificial intelligence (AI) software has expanded rapidly in recent years, and thus has emerged the importance of exploring human relationships with AI chatbots. Replika, an app which uses AI to mimic human conversation, removed a function called Erotic Role Play (ERP) that allowed for sexual conversation with users’ customizable chatbots in February of 2023. This exploratory qualitative study examines the aftermath of ERP’s removal through an analysis of user interactions on Reddit. Five overarching themes emerged through the analysis of top posts to a Replika-specific subreddit, encompassing topics around mental health, stigma, coping, sex work and gendered …

Phylogeny And Disparity Of Ammonoid Family Acanthoceratidae Over Ocean Anoxic Event 2, Lindsey Howard

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

The widespread use of genera as proxies for species in paleobiological studies might affect the results of these studies. Although most attention has been given to taxonomic diversity studies, this could also be true of disparity and phylogenetic studies. In particular, the assumption that particular character states truly diagnose all members of a genus might distort results. This study examines the disparity of Acanthoceratid ammonoids at both the generic and species level. 149 species from 42 genera were examined with 52 characters measured. Following the measurements, an inverse modeling simulation was run 100 times to generate a simulated phylogeny with …

Nonlocal Frameworks For Nonlinear Conservation Laws And Advection-Diffusion Processes, Anh Thuong Vo

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

Conservation laws are fundamental principles that play an important role in modeling various phenomena in physics, chemistry, and biology. However, their limitations, such as the development of shocks despite smooth initial conditions, are well known. The nonlocal model framework can be used to overcome these challenges. Nonlocal frameworks utilize integral operators that mimic differential operators but also incorporate long-range interactions within a finite horizon. This approach not only allows for non-smooth solutions, but also provides flexibility in modeling different phenomena. This study investigates the convergence of nonlocal divergence operators, defined with a general flux density function, to their classical counterparts. …

Integrating Remote Sensing And Machine Learning To Determine Past, Current And Future Crop Water Use From The Nubian Sandstone Aquifer System, Moaz Ishag

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

The agriculture sector is a significant consumer of water, and sustainable water use begins with monitoring irrigated land. Delineating irrigated land supports decision-makers and promotes the sustainable use of this crucial resource. This study focuses on the Nubian Sandstone Aquifer System (NSAS), the largest aquifers in the world, which spans Egypt, Sudan, Libya, and Chad. The study aims to: 1) quantify the increase in irrigated hectares (both pivot and non-pivot) from 2000-2001 to 2023-2024; 2) identify major irrigated crop types and their water requirements; and 3) quantify groundwater crop water use from the NSAS using remote sensing via the Google …

Enhancing Water Sustainability In North Africa: Literature Review And Synthesis Of Current Knowledge Gaps In Sudan, Osman M. A. Adam, Aaron R. Mittelstet, Derek M. Heeren, Troy E. Gilmore

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

This study delves into the critical role of groundwater in addressing global water challenges, with a focus on the Nubian Sandstone Aquifer System (NSAS) in North Africa. Groundwater constitutes a source of potable water, irrigation, and industrial use, especially in arid regions where surface water is limited. We analyzed the status of water quantity, withdrawals, recharge, and geological characteristics in the NSAS, specifically in Sudan, Egypt, Libya, and Chad. Though the NSAS is largely an untapped resource, we evaluated various scenarios to determine the quantity of cropland that can be sustainably irrigated. The NSAS is located in an arid region, …

Assessing Soil Properties For Optimized Irrigation Development In Sudan, Northern Africa, Suhib Hamid, Derek M. Heeren, Aaron R. Mittelstet, Saleh Taghvaeian, Randall S. Ritzema

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

Sustainable irrigation methods maximize agricultural productivity in Northern African countries like Sudan. This project evaluates soil properties to develop optimized irrigation strategies for Sudan's arid and semi-arid climate. Assessing soil characteristics such as texture, infiltration rates, and nutrient content informs the selection of modern irrigation systems. Data from 3,192 locations, collected using GPS and ring infiltrometers for infiltration rates, alongside laboratory analyses for soil properties, were employed. A ranking system determined suitable irrigation systems for specific soil classes, considering factors like slope, wind, crop tolerance, available water capacity (AWC), drainage, germination, capital cost, labor cost, maintenance, and evapotranspiration (ET). The …

Heat Stress Changes The Bovine Methylome And Transcriptome And Investigation Of Two Novel Genetic Defects In Cattle, Rachel Renae Reith

Department of Animal Science: Dissertations, Theses, and Student Research

Heat stress is a major concern for livestock producers due to its negative impact on animal health and productivity. Heat stress does so by altering expression of genes through different regulatory mechanisms such as DNA methylation. Understanding how heat stress alters gene expression will help elucidate the genetic basis of physiological changes as well as identify targets for possible heat stress mitigation. The purpose of the first study was to understand how heat stress alters the adipose and skeletal muscle transcriptomes in zilpaterol-fed Brahman, as zilpaterol improves muscle growth and may mitigate the effects of heat stress. Differential expression and …

Dynamic Metabolic Flux Analysis Amidst Data Variability: Sphingolipid Biosynthesis Case Study In Arabidopsis Thaliana Cell Cultures, Abraham Boluwatife Osinuga

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Sphingolipids are pivotal for plant development and stress responses. Growing interest has been directed towards fully comprehending the regulatory mechanisms of the sphingolipid pathway. In this study, we explore its de novo biosynthesis and homeostasis in Arabidopsis thaliana cell cultures, shedding light on fundamental metabolic mechanisms. Employing ¹⁵N isotope labeling and quantitative dynamic modeling approach, we obtained data with notable variations and developed a regularized and constraint-based Dynamic Metabolic Flux Analysis (r-DMFA) framework to predict metabolic shifts due to enzymatic changes. Our analysis revealed key enzymes such as sphingoid-base hydroxylase (SBH) and long-chain-base kinase …

Torus Surgery, Fibrations, Multisections, And Spun 4-Manifolds, Nicholas Paul Meyer

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

A compact n-manifold X is fibered if it is a fiber bundle where the fiber F and base space B are manifolds. Fibered manifolds are particularly nice, as they are essentially classified by their monodromy maps. Two common examples of 4-dimensional fibered manifolds are surface bundles over surfaces and 3-manifold bundles over the circle.

The main focus of this dissertation is to investigate fibered 4-manifolds whose boundaries are the 3-torus and how these manifolds glue together to give new closed, fibered 4-manifolds. In particular, suppose W is diffeomorphic to S¹ × E_Y (K) where Y …

A Case Study Of Mathematical Instructional Leadership, Theresa Haack

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

This dissertation looks at the impact of instructional leadership in mathematics teaching on teachers at various stages in their careers. Using a case study methodology, the researcher explores the nuanced needs and effective strategies for beginning, mid-career, and established teachers. Peer instructional leaders provided data that involved a mix of qualitative methods, including surveys, interviews, and questionnaires, targeting five assistant principals selected randomly from diverse school environments. The study identifies common themes and differences in instructional approaches, highlighting how strategies vary and overlap across different career stages. Analysis gives insights into the practical application of leadership in educational settings, emphasizing …

A Study Of Electron- And Photon-Induced Dissociative Electron Attachment To Molecules And Within Anion-Molecule Clusters, Mahmudul Hasan

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

Dissociative electron attachment (DEA) is a resonant process in which a molecule captures a low-energy electron, forming a transient negative ion (TNI). Subsequently, this unstable TNI fragments into a stable anion and one or more neutral fragments. DEA is crucial in various phenomena, ranging from atmospheric and radiation chemistry to processes occurring in plasmas, and is particularly significant in the context of radiation-induced damage to biological molecules. This study uses different experimental methods to better understand the fragmentation in molecular anions forming through dissociative photoexcitation and electron attachment. We have developed an experimental apparatus for dissociative photoexcitation studies. This apparatus …

Exploring The Associations Of Afterschool Science Participation And Friendships With Science Identities, Patricia Wonch Hill, Grace M. Kelly, Julia Mcquillan, Jorge Ledesma, Miranda Melson, G. Robin Gauthier

Worlds of Connections Resources

Building on previous research that demonstrates the association of youth experiences in afterschool science and higher science identities, this paper presents a network study of 421 middle school students that examines afterschool science participation, friendship ties, and science identities. Participation in afterschool science clubs is associated with higher science identity, but the mechanisms and order of causality are unclear. Youth form friendships inside and outside of school, and peers may influence participation in afterschool activities, as empirical research on friendships shows that they are associated with youth interests. These peer interactions also have the potential to shape identity development during …

Evaluation Of An Autonomous Acoustic Surveying Technique For Grassland Bird Communities In Nebraska, Grace E. Schuster, Leroy J. Walston, Andrew R. Little

School of Natural Resources: Faculty Publications

Monitoring trends in wildlife communities is integral to making informed land management decisions and applying conservation strategies. Birds inhabit most niches in every environment and because of this they are widely accepted as an indicator species for environmental health. Traditionally, point counts are the common method to survey bird populations, however, passive acoustic monitoring approaches using autonomous recording units have been shown to be cost-effective alternatives to point count surveys. Advancements in automatic acoustic classification technologies, such as BirdNET, can aid in these efforts by quickly processing large volumes of acoustic recordings to identify bird species. While the utility of …

Perspectives On Computational Modeling Of Biological Systems And The Significance Of The Sysmod Community, Bhanwar Lal Puniya, Meghna Verma, Chiara Damiani, Shaimaa Bakr, Andreas Dräger

Department of Biochemistry: Faculty Publications

Motivation: In recent years, applying computational modeling to systems biology has caused a substantial surge in both discovery and practical applications and a significant shift in our understanding of the complexity inherent in biological systems.

Results: In this perspective article, we briefly overview computational modeling in biology, highlighting recent advancements such as multiscale modeling due to the omics revolution, single-cell technology, and integration of artificial intelligence and machine learning approaches. We also discuss the primary challenges faced: integration, standardization, model complexity, scalability, and interdisciplinary collaboration. Lastly, we highlight the contribution made by the Computational Modeling of Biological Systems …

A Comprehensive Study On The Impact Of Human Hair Fiber And Millet Husk Ash On Concrete Properties: Response Surface Modeling And Optimization, Naraindas Bheel, Muhammad Alamgeer Shams, Samiullah Sohu, Abdul Salam Buller, Taoufik Najeh, Fouad Ismail Ismail, Omrane Benjeddou

Department of Civil and Environmental Engineering: Faculty Publications

Revolutionizing construction, the concrete blend seamlessly integrates human hair (HH) fibers and millet husk ash (MHA) as a sustainable alternative. By repurposing human hair for enhanced tensile strength and utilizing millet husk ash to replace sand, these materials not only reduce waste but also create a durable, eco-friendly solution. This groundbreaking methodology not only adheres to established structural criteria but also advances the concepts of the circular economy, representing a significant advancement towards environmentally sustainable and resilient building practices. The main purpose of the research is to investigate the fresh and mechanical characteristics of concrete blended with 10–40% MHA as …

Production Of The Siderophore Lysochelin In Rich Media Through Maltose-Promoted High-Density Growth Of Lysobacter Sp. 3655, Fang Zhang, Jia Liu, Lin Jiang, Yongbiao Zheng, Lingjun Yu, Liangcheng Du

Department of Chemistry: Faculty Publications

Siderophores are produced by bacteria in iron-restricted conditions. However, we found maltose could induce the biosynthesis of the siderophore lysochelin in Lysobacter sp. 3655 in rich media that are not compatible with siderophore production. Maltose markedly promoted cell growth, with over 300% increase in cell density (OD₆₀₀) when LB medium was added with maltose (LBM). While lysochelin was not detectable when OD₆₀₀ in LBM was below 5.0, the siderophore was clearly produced when OD₆₀₀ reached 7.5 and dramatically increased when OD₆₀₀ was 15.0. Coincidently, the transcription of lysochelin biosynthesis genes was remarkably enhanced following the …

Concepts In Animal Parasitology, Scott L. Gardner, Sue Ann Gardner

Zea E-Books Collection

Note that this version of the textbook has been superceded by the one updated in 2026, available at the UNL Pressbooks site.

The hard copy version that is for sale at lulu.com is the old version.

"This is a textbook covering concepts in animal parasitology. It is meant to be used by students, teachers, professors, researchers, and members of the public who are interested in learning about animal parasite biology, systematics, taxonomy, zoogeography, and ecology. The primary intended audience is upper-level undergraduate or graduate university students who have knowledge of basic biology and, particularly, basic animal biology. (863 pages, …

Cellmarkerpipe: Cell Marker Identification And Evaluation Pipeline In Single Cell Transcriptomes, Yinglu Jia, Pengchong Ma, Qiuming Yao

School of Computing: Faculty Publications

Assessing marker genes from all cell clusters can be time-consuming and lack systematic strategy. Streamlining this process through a unified computational platform that automates identification and benchmarking will greatly enhance efficiency and ensure a fair evaluation. We therefore developed a novel computational platform, cellMarkerPipe (https:// github. com/ yao- labor atory/ cellM arker Pipe), for automated cell-type specific marker gene identification from scRNA-seq data, coupled with comprehensive evaluation schema. CellMarkerPipe adaptively wraps around a collection of commonly used and state-of-the-art tools, including Seurat, COSG, SC3, SCMarker, COMET, and scGeneFit. From rigorously testing across diverse samples, we ascertain SCMarker’s overall reliable performance …

Topological Regression As An Interpretable And Efficient Tool For Quantitative Structureactivity Relationship Modeling, Ruibo Zhang, Daniel Nolte, Cesar Sanchez-Villalobos, Souparno Ghosh, Ranadip Pal

Department of Statistics: Faculty Publications

Quantitative structure-activity relationship (QSAR)modeling is a powerful tool for drug discovery, yet the lack of interpretability of commonly used QSAR models hinders their application inmolecular design.We propose a similaritybased regression framework, topological regression (TR), that offers a statistically grounded, computationally fast, and interpretable technique to predict drug responses. We compare the predictive performance of TR on 530 ChEMBL human target activity datasets against the predictive performance of deep-learning-based QSAR models. Our results suggest that our sparse TR model can achieve equal, if not better, performance than the deep learningbased QSAR models and provide better intuitive interpretation by extracting an approximate …

Cost Modeling Of Provision C.3 Green Stormwater Infrastructure Requirements For Residential Development In Concord, California, James Henry Mizutani

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

To assist the city of Concord in achieving its housing goals as presented in its general plan, while still meeting the stormwater discharge requirements laid out in the city’s municipal discharge permit, I worked with local developers and consultants to create a spreadsheet modeling tool that allows housing developers to estimate the total cost of green stormwater infrastructure needed to comply with local regulations.

This report contains a summary of the conditions leading to the necessity of this tool, the steps the tool takes that go beyond existing models, a description of how the model operates, instructions on how to …

Modeling And Design Parameter Optimization To Improve The Sensitivity Of A Bimorph Polysilicon-Based Mems Sensor For Helium Detection, Sulaiman Mohaidat, F. M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

Helium is integral in several industries, including nuclear waste management and semiconductors. Thus, developing a sensing method for detecting helium is essential to ensure the proper operation of such facilities. Several approaches can be used for helium detection, including based on the high thermal conductivity of helium, which is several times higher than air. This work utilizes the high thermal conductivity of helium to design and analyze a bimorph MEMS sensor for helium sensing applications. COMSOL Multiphysics software (version 6.2) is used to carry out this investigation. The sensor is constructed from poly-silicon and SiO₂ materials with a trenched …

An Inaugural Forum On Epidemiological Modeling For Public Health Stakeholders In Arizona, Joseph R. Mihalijevic, Carmenlita Chief, Mehreen Malik, Kayode Oshinubi, Eck Doerry, Esma Gel, Crystal Hepp, Tim Lant, Sanjay Mehrotra, Samantha Sabo

Department of Supply Chain Management and Analytics: Faculty Publications

Epidemiological models—which help us understand and forecast the spread of infectious disease—can be valuable tools for public health. However, barriers exist that can make it difficult to employ epidemiological models routinely within the repertoire of public health planning. These barriers include technical challenges associated with constructing the models, challenges in obtaining appropriate data for model parameterization, and problems with clear communication of modeling outputs and uncertainty. To learn about the unique barriers and opportunities within the state of Arizona, we gathered a diverse set of 48 public health stakeholders for a day-and-a-half forum. Our research group was motivated specifically by …

Morphometric Analysis And Taxonomic Re-Evaluation Of Pepsis Cerberus Lucas And P. Elegans Lepeletier (Hymenoptera: Pompilidae: Pepsinae: Pepsini), Frank E. Kurczewski, Akira Shimizu, Diane H. Kiernan

Insecta Mundi

Hurd (1952) separated Pepsis cerberus Lucas from P. elegans Lepeletier (Hymenoptera: Pompilidae: Pepsinae: Pepsini) based on external morphology and biogeography. Vardy (2005) synonymized the familiar and historically well-documented P. cerberus and P. elegans, combining these Nearctic taxa with several Neotropical variants in an extremely broad definition of P. menechma Lepeletier. In doing so, Vardy (2005) breached the principle of nomenclatural stability. He ignored the prevailing usage and clearly violated articles 23.2, 23.3 and 23.9.1.2 of the ICZN (1999). Morphological differences, ecological divergence, and narrow sympatric geographic distribution of P. cerberus and P. elegans …