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Exploring Mimicry And Visual Communication In Woodpeckers: A Field Study Utilizing 3d-Printed Models, Lauren M. Smith

Biology Theses

The evolution of similar phenotypes poses an interesting challenge in evolutionary biology. While divergent ecologies may drive differing morphology, physiology, or behavior, similar phenotypes are often due to similar ecology or selection for mimicry. One prominent case of mimetic phenotypes is found in hairy and downy woodpeckers. While several hypotheses might explain the hairy-downy mimicry complex, I aimed to assess the idea that downy woodpeckers benefit from resembling hairy woodpeckers. To test this hypothesis, I used 3D-printed models of various woodpecker species in the field. These models were painted with colors that resemble woodpecker species. The experimental conditions were 3D …

Pollination Synchrony Along A Great Lakes Thermal Gradient, Joe Armstrong

Biology Theses

Pollination is an essential mutualistic interaction between plants and animals. Often agricultural crops rely on successful pollination to provide profitable and nutrient rich harvests. Successful pollination requires synchrony between flowers and pollinators. Western New York with its proximity to the Great Lakes has benefited as a Climate refugia; however, recent climate change and increased temperature variation have threatened regional fruit crops. In this thesis, I explored the synchrony between native pollinators, non-native pollinators, and apple flowering along a coastal to inland gradient for farms in Niagara County. I measured temperature, evaluated apple flower phenology, and harvested pollinators during the Spring …

Mitigating Nitrogen Losses: The Role Of Enhanced Efficiency Fertilizers In Sustainable Corn Production, Dipesh Giri

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

Nitrogen (N) is essential for crop production, but its inefficient use often leads to environmental losses through nitrate leaching, ammonia volatilization, and nitrous oxide (N₂O) emissions. Enhanced efficiency fertilizers (EEFs), such as nitrification inhibitors (NIs) and urease inhibitors (UIs), have been developed to minimize these losses and improve nitrogen use efficiency (NUE). This research combined a multi-year field experiment and a controlled laboratory study to evaluate how dual-inhibitor fertilizers compare to conventional urea and single-inhibitor formulations in Nebraska cropping systems. The main objective was to understand how nitrogen inhibitors influence N availability, crop performance, and nitrogen losses across different environmental …

Improving Nitrogen Management And Corn Productivity Through Enhanced Efficiency Fertilizer And Cover Crop Integration In Nebraska Cropping Systems, Madhusudhan Adhikari

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

Effective nitrogen (N) management is vital for sustaining corn yield and reducing environmental impacts in Nebraska cropping systems. Three field studies were conducted to evaluate the impact of 1) fertilizer type (anhydrous ammonia [AA] with nitrification inhibitor: enhanced efficiency fertilizer [EEF] or AA without EEF) and N application timing (pre-plant vs. split with side-dress UAN) on in-season soil N availability, crop response, nitrous oxide (N₂O) emissions, residual soil N and N use efficiencies (NUEs); 2) winter cover crop (CC) species and crop rotation variability on CC biomass production, N uptake, soil N dynamics, and cash crop performance in …

Extending Cover Crop Growing Window To Improve The Health Of Environmentally Sensitive Soils, Noshin Ara Tunazzina

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

Sloping and sandy soils are highly susceptible to degradation. The health of these soils could be improved with cover crops (CCs). However, CC effectiveness in improving soil health mainly depends on CC biomass production, which is often low in temperate regions. The question is: how can we increase CC biomass production? Lengthening the CC growing window can be a potential strategy. This study assessed how 1) interseeded and terminated early (2-3 weeks before crop planting) CC, 2) interseeded and terminated late (at crop planting) CC, 3) drilled (after harvest) and terminated early CC, 4) drilled and terminated late CC, and …

Characterizing Xylella Fastidiosa Pathogen Dynamics On Diverse Small Fruit Farms, Alexandra Ratay

All Theses

Global agriculture has been threatened for over a century due to the emergence of the plant pathogenic bacteria Xylella fastidiosa (Lysobacterales: Lysobacteraceae) (Xf). Xf comprises five main subspecies and induces severe physiological symptoms in a diverse set of host plant species by limiting xylem function. Xylem-feeding insect vectors can transmit Xf to host plants, spreading disease and reducing fruit yield. Here I studied Xf prevalence on small fruit farms to determine Xf host plant and vector infective status to the Xf subspecies level. I detected Xf in 28 host plants in South Carolina containing either Xf subspecies fastidiosa …

Don’T Be A Big Baby: Phenotypic Novelty In The Facultative Paedomorph Ambystoma Talpoideum., Andrew S. Kanes

All Theses

This thesis explores the relationship between heterokairy and the skin microbiota of amphibians, specifically focusing on the facultatively paedomorphic salamander, Ambystoma talpoideum. Heterokairy refers to variations in developmental timing that generate phenotypic novelty within life stages. The first chapter investigates how reordering metamorphosis relative to sexual maturation affects the skin microbiota in this species. By sampling different life stages—larval, paedomorphic, and metamorphic—results show the emergence of novel microbial combinations, resulting from both microbial gain and loss in the heterokairic paedomorphic stage. These findings suggest that changes in microbial communities may lead to phenotypic novelty and have broader eco-evolutionary implications. …

Application Of Remote Sensing In Mapping Callery Pear Distribution And Biomass Estimation In The Southeastern United States, Kavi Raj Awasthi

All Theses

Callery pear (Pyrus calleryana Decne. Rosaceae) is a rapidly spreading invasive species in the southeast United States (US) that hampers the function of native tree species and the forest ecosystem. Native to Southeast Asia, the species has encroached on the natural and secondary vegetation habitats of the Southern US in recent years. This study attempted to 1) map the Callery pear across the southeast US and 2) model the aboveground biomass (AGB) of individual Callery pear trees.

We used Callery pear locations and winter imageries of Sentinel-2, Sentinel-1, L-band radar, and terrain imagery for mapping purposes. In addition, we …

Healthy Dietary Patterns’ Impact On Depressive Symptoms: A Meta-Analysis Of Randomized Controlled Trials, Angela Encardone

All Theses

As the search for innovative mental health treatments expands, dietary interventions have emerged as a promising approach for alleviating depressive symptoms. This thesis presents a meta-analysis of randomized controlled trials (RCTs) examining the efficacy of whole-of-diet nutritional interventions in reducing depression symptoms among adults. Grounded in Bronfenbrenner’s Bioecological Model and Engel’s Biopsychosocial Model, this study explores the intersection of biological, psychological, and social factors that influence mental health outcomes. A systematic review identified six eligible RCTs assessing the impact of healthy dietary patterns, including the Mediterranean diet and other plant-based interventions, on depression symptoms. A random-effects meta-analysis revealed a significant …

Effects Of Common Herbicides On Organismal Interactions, Robert Chamberlin

All Theses

Pesticides are applied to agricultural lands to prevent undesirable weeds, animal pests, and fungi from harming crops and reducing crop yields. Pesticides are used in croplands at increasing rates around the world and have become an essential component of farming in recent decades. Often, rain, wind, and soil permeation move pesticides from farmlands to natural environments. Such contamination of natural environments by pesticides may threaten species by altering their behaviors, bodily functions, and the ways in which individuals interact. Atrazine and glyphosate are among the most widely used herbicides around the world and are useful in eliminating weeds, primarily in …

Risky Genes: The Impact Of Social Determinants Of Health On Dna Methylation In Indigenous Communities, Ella Martin

Celebrating Scholarship and Creativity Day (2018-)

Epigenetics is the study of molecular modifications to DNA structure that do not impact the sequence of the DNA itself. This biological study works to link health outcomes later in life with environmental interactions that affect our genetic predispositions. These complex factors can greatly impact longevity and quality of life. DNA methylation is one type of epigenetic mark that happens through natural biological processes. However, this marking has been shown to be detrimental to the process of aging and can be accelerated by harmful exposures such as stress, substance-use, or chemicals in the environment. Exposure to these compounds is exasperated …

Leveraging Natural Variation In Yeast To Understand Susceptibility Differences In Parkinson’S Disease, Julio Andres Molina Pineda

Graduate Theses and Dissertations

Parkinson’s Disease (PD) is a neurodegenerative disorder that causes countless suffering around the world. Both forms, familial and sporadic, have been associated with the misfolding and cytotoxicity of α-synuclein, an otherwise non-pathogenic protein suspected to have various roles in the normal maintenance of the central nervous system. Model organisms have emerged as great vessels to uncover the cellular and molecular mechanisms that shape α-syn biology, and great strides have been made to understand it. Yet, it is still unclear why some individuals are affected by α-syn toxicity, while others not so much. Since it’s extremely complicated to study and probe …

Utility Of John Deere's See & Spray Ultimate In Southern U.S. Row Crops, Tristen Avent

Graduate Theses and Dissertations

Row crop producers across the southern United States are observing a boom in technological advancement to improve operational efficiency. Additionally, environmental concerns and reduced profit margins drive the adoption of targeted pesticide application technologies like the John Deere See & Spray. This technology is relatively new, introduced in 2022, and producers need more insight into the shortcomings, potential herbicide savings, and the economic benefits of adoption. Since 2021, research has been conducted in Keiser, AR, with additional collaborative projects in Mississippi, North Carolina, Indiana, and Illinois. Five different objectives were addressed in this research: 1) to determine the impact of …

Examining The Molecular Mechanisms Of Glucagon-Like Peptide-1 Receptor Agonists In Cancer Cell Biology, Oliver G. Sabet

Honors Scholar Theses

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are synthetic analogs of glucagon-like peptide-1 (GLP-1) used to treat obesity and diabetes by reducing blood glucose levels and appetite. While early rodent studies suggested a link between GLP-1RAs and thyroid cancer pathogenesis, evidence in humans remains inconclusive, with randomized controlled trials not supporting that link. Due to the rapid, widespread use of these drugs, concerns have expanded to other obesity-associated cancers, with conflicting findings on their role in cancer progression. With this contradictory evidence in a novel intersection of obesity medicine and oncology, this literature review aims to summarize current understandings between GLP-1-RAs and …

The Role Of Myosin L In The Survival Of Toxoplasma Gondii And The Importance Of Mlc1 For In Vitro And In Vivo Myosin F Motility, Victoria K. Yi

Honors Scholar Theses

My thesis discusses the work that I have conducted on two myosins in Toxoplasma gondii, which is an obligate intracellular parasite that has chronically infected around 10% of the American population. It causes toxoplasmosis and severe health consequences for individuals with compromised immune systems or when infections occur in utero. However, immunocompetent individuals are asymptomatic or present with subclinical symptoms. In the Heaslip lab, I investigated two myosins in the parasite: Myosin L and Myosin F. MyoL is an uncharacterized motor that localizes at the apical end of the parasite. It was shown to be important for parasite …

Identifying Cognitive, Affective, And Developmental Mechanisms Linking Threat And Deprivation With Adolescent Psychopathology, Ekaterina Sadikova, David G. Weissman, Maya L. Rosen, Elise Robinson, Liliana J. Lengua, Margaret A. Sheridan, Henning Tiemeier, Katie A. Mclaughlin

Neuroscience: Faculty Publications

Background: The mechanisms linking early-life adversity with psychopathology over the life-course are complex. In this prospective study, we collectively examined cognitive, affective, and developmental mediators previously found to individually link childhood threat and deprivation experiences to adolescent psychopathology to identify the most potent mechanisms. Methods: Data came from a community sample of 227 children (mean child age 11.5 ± 0.5 years, 48.5% female) from the Seattle metro area with recruitment designed to reflect diversity in family income. Candidate mechanisms included self-rated pubertal development and task-measured attention bias to threat, emotion regulation, theory of mind, fear learning, inhibitory control, language ability, …

Dna Gyrase Inhibition By Ni(Ii)-Schiff Base Complexes Via In Silico Molecular Docking Studies: Spectroscopic, Dft Calculations And In Vitro Pharmacological Assessment, Ikechukwu P. Ejidike, Amani Direm, Cemal Parlak, Solomon A. Olaleru, Charles O. Adetunji, Athar Ata, Et. Al.

Michigan Tech Publications

The current world's life-threatening illnesses have amplified multidrug resistance infections, bringing about immune system mayhem, thus, the quest for novel antimicrobial compounds with a broad spectrum of action. Four Ni(II) complexes, [Ni(YB)Cl]·2H₂O (C1), [Ni(YB)Br]·H₂O (C2), [Ni(YB)NO₃]·3H₂O (C3), [Ni(YB)COOCH₃]·2H₂O (C4) [HYB = 4-[(1E)-N-{2-[(Z)-(4-methoxybenzylidene)amino]ethyl}ethanimidoyl]benzene-1,3-diol], were synthesized. Analytical techniques like CHNS analysis, UV–Vis, FT-IR, molar conductance, XRD, ¹H NMR, and TGA/DTA were utilized for characterization. The calculated …

Assessment Of Lake Salvador Shoreline Dynamics To Support Restoration Of Submerged Aquatic Vegetation In Jean Lafitte National Historical Park And Preserve, Louisiana, Lydia V. Dipaola

LSU New Orleans Theses and Dissertations

High wave energy degrades shoreline habitat between Lake Salvador and Jean Lafitte National Historical Park and Preserve (JELA), Louisiana. JELA constructed a northern breakwater in 2004, and a southern breakwater in 2024 to protect the shoreline and promote restoration of submerged aquatic vegetation (SAV). This study analyzes Sentinel-2 imagery to quantify coastal loss along the JELA-Lake Salvador using the Change Polygon Approach, assessing annual, cumulative and major storm event-associated shoreline changes for January 2017-2025. SAV cover, nekton diversity, wave energy, and turbidity were measured before-and-after southern breakwater construction to monitor ecological and environmental outcomes. The JELA-Lake Salvador shoreline has lost …

Gene Expression And Transfection Of C15orf57 In Chicken Show Clear Correlation To The Function Of The Ap2 Complex, E. Ashton Magdich

Graduate Theses and Dissertations

Discovering the functions of functionally unknown genes has made a huge impact on biological understanding including poultry species. In this thesis, C15orf57 (or C5H15orf57, chicken chromosome 5 human ortholog H15 open reading frame 57), was studied to understand its genetic characteristics and function. Chapter one is literature reviews on annotation of genes, the gene information on C15orf57, the importance of characterizing unknown genes in the genome, and what is known now about C15orf57. The Chapter 2 is for the structural characterization of C15orf57, gene expression of C15orf57 in various organ tissues using the qPCR method and effect of overexpression of …

Impacts Of Toxic Fescue Seed Consumed By Pregnant Heifers On Maternal Blood Flow And Offspring Growth Parameters: Potential For Melatonin As A Therapeutic To Improve Offspring Growth, Rachel Scott

Graduate Theses and Dissertations

The southeastern United States is home to endophyte-infected (E+), toxic, tall fescue grass. Consumption of E+ fescue by livestock has been linked to fescue toxicosis, a disease reported to cost the United States beef industry around $1 billion in annual losses. The primary objective of this dissertation was to evaluate the influence of pregnant cattle consuming E+ seed during gestation on uterine artery blood flow and growth performance of female offspring. The secondary objective was to investigate melatonin supplementation as a mitigation strategy for expected fescue-associated decreases in uterine artery blood flow and offspring growth performance. The study reported in …

Effects Of Cholesterol Concentration On Liposome And Proteoliposome Behavior, Ehsaneh Khodadadi

Graduate Theses and Dissertations

Cholesterol is crucial in modulating the behavior and characteristics of biological membranes, liposomes, and proteoliposomes, for instance in drug delivery applications. Cholesterol regulates membrane stability by influencing lipid density, phase separation, and protein-membrane interactions. In planar bilayers, cholesterol enhances membrane thickness, reduces permeability, and promotes lipid ordering, adding rigidity and fluidity. Cholesterol also modulates membrane curvature in curved bilayers and vesicles, stabilizing low-curvature regions. In this work, all-atom molecular dynamics (MD) simulations were employed to examine how varying cholesterol concentrations influence the structure and dynamics of membranes, focusing on planar and curved geometries. Bilayers with cholesterol molar ratios of 0%, …

Supplementation Of Magnesium Glycinate: Testing The Acute Effects Of Magnesium Glycinate On The Stress Levels Of College Students, Meagan Bubeck

Honors Theses

he usage of supplements and vitamins to increase health has become a common practice in the United States. However, the true effects are not always well-known and can differ across brands, population, and other factors. In college, many students are functioning in high stress conditions, and some may result to going on anti-anxiety or depression medications. To see if Magnesium supplementation could be a potential first step in improving the stress levels present in the student population, the effects of Mg were studied in a population of 10 participants. Participant data was studied in both an Mg and placebo condition …

Determining The Influence Of A Low-Head Dam On Macroinvertebrate Communities In The Bouie River, Natalie Santiago

Honors Theses

The Bouie River is a tributary of the Leaf River and belongs to the Pascagoula River watershed, the latter of which has no flow impediments in the form of sills or dams. The Bouie River has been heavily altered in the lower 10 river kilometers (rkm) from aggregate mining (creating a series of deep gravel pits) and the presence of an earthen and concrete low-head dam (sill) located 6 rkm from the mouth of the river. However, despite these alterations, the immediate stretch of river below the low-head dam is a known spawning habitat for diadromous fish species, including the …

Transcriptional Analysis Of Inflammatory Responses Of Mouse Trophoblast Stem Cells To Interferon Gamma, Arnaz Maryam Tariq

Honors Theses

The blastocyst faces significant immunological challenges during implantation, including heightened inflammation, which can contribute to implantation failure. Trophoblast stem cells (TSCs) and their differentiated forms (TSC-TBs), derived from the trophectoderm (TE) of the blastocyst, play a crucial role in immune modulation. Previous studies suggest that interferon-stimulated genes (ISGs) derived from TSC and TSC-TB provide antiviral protection to embryonic stem cells (ESCs). These findings show indication of a potential antiviral role for placental progenitors in shielding the blastocyst. Additionally, TSCs and TSC-TBs exhibit selectively attenuated immune responses to the proinflammatory cytokine interferon-gamma (IFN-γ) compared to mouse embryonic fibroblasts (MEFs). The attenuated …

Direct Synthesis Of Cerium Oxide Nanoparticles In Reducing Sugars: Enhanced Ce3+ Surface Density For Biological Application, Balaashwin Babu, Elayaraja Kolanthai, Craig J. Neal, Samarah V. Harb, Udit Kumar, Yifei Fu, Sudipta Seal

Rowan-Virtua Research Day

Cerium oxide nanoparticles (CNPs) are recognized for their ability to scavenge reactive oxygen species (ROS), making them promising candidates for mitigating oxidative damage in biomedical applications. However, many conventional synthesis methods limit the formation of Ce³⁺ states, which are critical for this antioxidant function. Building upon previous findings that glucose can promote Ce³⁺ formation, this study investigates the broader impact of both reducing (glucose, fructose, galactose) and non-reducing (dextran, sucrose, cyclodextrin) natural sugars on CNP synthesis. CNPs were synthesized in the presence of these sugars, and the surface densities of Ce³⁺ were measured. Results showed that reducing sugars significantly increased …

Movement Ecology Of Sandhills Chub, A Carolina Endemic, Zachary Adam Ramsey

Electronic Theses and Dissertations

Fish movement studies have traditionally focused on species that support commercial and recreational fisheries, but recently more focus has been given to non-game, stream fishes because of their recognized importance in maintaining biodiversity within these ecosystems. Stream fish movement is described as being “restricted” and following a leptokurtic distribution via diffusive spread related to environmental and biological factors. Many studies of stream fish movement ecology in North America have occurred in high-gradient streams with coarse substrate in mountains or in streams of the interior plains. Sandhills streams of the southeastern USA are characterized as warm-water, low gradient, and dominated by …

Flow Field Surrounding Bluegill (Lepomis Macrochirus) During Suction-Feeding, Jensine Caroline Coggin

Electronic Theses and Dissertations

Suction-feeding is a common method for capturing prey by aquatic organisms and contributed to the diversification of fishes by enabling them to consume a wide range of prey. Suction-feeding is a complex fish-fluid interaction governed by various hydrodynamic forces: inertia, unsteady, viscous, and pressure gradients. These forces are described by the coupling between the flow physics equations (Navier-Stokes) and the dynamic behavior of the fish (motion and forces). However, the distribution of the pressure field that drives this process, and the extent to which suction-feeding is three-dimensional, remain underexplored. I estimated the pressure within the flow field surrounding the mouth …

Heterotopias Of Confinement: Zoo Architecture And The Loss Of Elephant Agency, Clayton Gill Beasley

Electronic Theses and Dissertations

Zoos functions as a site where human-animal relationships are structured through built environments that mediate control and representation. This study examines zoos as heterotopias—spaces where power and surveillance are negotiated between human observers and captive nonhuman animals. While zoos are often framed as spaces of conservation and education, their architectural design reinforces hierarchies of observation and confinement, shaping both human perceptions of nature and the lived experiences of nonhuman animals. This research focuses on Asian elephants as a critical species within this framework, exploring how their captivity illuminates tensions between human-imposed structures and nonhuman autonomy. Drawing from theories of heterotopia, …

Kinasefusiondb: An Integrative Knowledge Of Kinase Fusion Proteins In Multi-Scales, Himansu Kumar, Zikang Chen, Abayomi Adegunlehin, Loren Trowbridge, Leonardo Aguilar, Pora Kim

Faculty, Staff and Student Publications

Kinase fusion genes were the most targeted fusion gene group among multiple major cellular gene groups. Kinase inhibitors disrupt aberrant signaling cascades and inhibit tumor progression, yet the specific mechanisms of action of the U.S. Food and Drug Administration (FDA)-approved inhibitors in the context of kinase fusion oncoproteins remain largely unknown. This gap limits our ability to develop personalized therapies and next-generation kinase inhibitors. To address this, we developed a novel in silico pipeline for predicting 3D structures of kinase fusion proteins and performing structure-based virtual screening. This approach enables large-scale structural annotation and drug screening across pan-cancer kinase fusions. …

Implications Of Type Iv Pilus Retraction For Dna Uptake By Acinetobacter Baumannii, Yafan Yu

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

Horizontal gene transfer (HGT) via natural competence allows bacteria to incorporate extracellular DNA (eDNA) into their genomes, facilitating genetic diversity and adaptation. In Acinetobacter species, natural competence depends on DNA binding and uptake mediated by type IV pili (T4P). T4P are dynamic extracellular filaments composed primarily of the major pilin subunit PilA, along with a few minor subunits. T4P drive a range of cellular functions including twitching motility, biofilm formation, and DNA uptake, with some functions dependent on pilus retraction and others not. However, how Acinetobacter T4P bind DNA and how T4P/eDNA interactions impact biofilm formation remain unclear. Here, I …