Life Sciences Commons^™

Virion Composition Of Wheat Streak Mosaic Virus (Wsmv) And Its Use As An Expression Vector, Sourav Pal

Department of Plant Pathology: Dissertations, Theses, and Student Research

Wheat (Triticum aestivum L.) is the principal cereal grown in the United States, whose production ranks third in the world. Bacterial leaf streak (BLS) disease caused by Xanthomonas translucens pv. undulosa (xtu) is an emerging threat to wheat production in the Great Plains region of the United States of America. In this study, we engineered sequences encoding several plant-based antimicrobial peptides (AMP) were engineered into the WSMV genome and examined their effect on BLS disease in wheat infected by WSMV harboring AMP sequences. Out of nine AMPs, wheat expressing Ace-AMP1, PDF13, TK-AMP-D1, and TK-AMP-D3 produced resistance against the …

Transforming Grassland Conservation: Challenges And Opportunities Across Law, Policy, And Human Dimensions, Conor D. Barnes

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

Great Plains social-ecological systems are facing growing pressure from complex, ‘wicked’ problems. Addressing these problems will require integrating ecological resilience and complex systems thinking concepts into our legal framework in order to better reflect the changing ecological reality of the Great Plains and promote flexibility and adaptability in the face of that change. In this dissertation, I examine how past and present policy priorities have affected social-ecological systems on the Great Plains, and how ecological resilience and complex systems thinking might be applied to grassland management policy. In Chapter 2, I examine the rapid progress made in the adoption of …

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 …

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 …

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 …

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 …

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; …

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 …

Linking Risk Preference, Women’S Empowerment, Farm Investment And Household Well-Being, Samuel Olusesi Olumide

Department of Agricultural Economics: Dissertations, Theses, and Student Research

A nuanced understanding of intra-household dynamics can inform the design of more effective empowerment and agricultural investment policies. By integrating household risk preferences and empowerment dynamics, this work offers valuable insights into the complex mechanisms driving household welfare and provides a framework for future interventions to promote gender equality and economic development in rural settings. This thesis addresses three core hypotheses: first, that the spouses of risk-seeking male heads are more likely to be disempowered compared to those of risk-averse male heads; second, that households with risk-seeking male heads and disempowered spouses are likely to invest more in farming activities; …

Investigating Associations Between Activity And Performance Traits Across Three Breeds Of Swine Using NuTrack, Dalton R. Obermier

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

Feed costs are the largest contributor towards the variable costs of pork production. To decrease feed cost while not sacrificing output requires an improvement in feed efficiency (FE). A potential approach to expand available phenotypes associated with FE is with activity tracking, yet the relationship between activity and performance is not well defined in swine. Therefore, the objective of this study was to quantify associations between activity and feed intake traits. Average daily feed intake (ADFI) was collected on 1,766 purebred boars of three genetic lines (Duroc, Landrace, and Yorkshire) using FIRE (Osborne Industries, Inc., Osborne, Kansas) at a testing …

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 …

Understanding The Role Of The Microbiome In Infectious Disease, Developing Surveillance Tools, And Engineering Direct Fed Microbials To Improve Animal Health, Alison Clare (Bartenslager) Neujahr

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

With the ever-increasing demand for animal protein and the continual need for the assurance of proper animal welfare, investigations of preventative strategies for diseases is greatly needed. Specifically in the cattle industry, infectious bovine keratoconjunctivitis (IBK), commonly known as pinkeye, causes a large economic loss to the producer. However, effective mitigation strategies are lacking. Partly, this is due to the lack of studies investigating the ocular microbiome. Therefore, studies investigating the bovine ocular microbiome are greatly needed to better understand IBK disease etiology. To this end, we investigated the changes in the ocular microbiome in animals before, during and after …

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 …

Development And Validation Of Aronia Melanocarpa Berry Recipes For Home Canning: Integrating Thermal Lethality Studies, Microbiological Safety, And Antioxidant Analysis, Juan Diego Villegas Posada

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Aronia melanocarpa, also known as chokeberry, is gaining popularity for its high antioxidant content and health benefits, including reducing oxidative stress and inhibiting cancer gene expression. However, its characteristic bitterness and astringency limit its broader appeal. Chokeberry's low pH places it in the acid foods category, making it ideal for safe home canning. An acidic environment combined with heat treatment inhibits harmful bacteria like Clostridium botulinum. Home canning preserves food by sealing it in airtight containers and heating it to destroy spoilage microorganisms.

Developing safe and palatable recipes is essential for making chokeberries suitable for home canning. A …

Preschool Executive Control And Adolescent Dietary Outcomes: Highlighting The Role Of Context, Marla Lopez

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

Research has identified executive control (EC) as an important predictor of dietary outcomes among youth. Executive control in preschool age has been shown to predict important outcomes across development for youth, indicating that good, foundational EC abilities are associated with successful development in later life. Dietary outcomes across adolescence, an important transitional period for establishing healthy eating behaviors, are understudied. Therefore, the current study sought to link two critical developmental periods, examining how preschool EC is associated with dietary trajectories across adolescence. Further, the study aimed to identify how contextual factors, specifically indices of socio-economic status and the home and …

Candida Albicans Farnesol Synthesis And Secretion, Daniel John Gutzmann

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

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 …

Development Of An Egg-Specific Mass Spectrometry Targeted Method For Processed Food Matrices, Liyun Zhang

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

Egg is a major food allergen in the United States, causing symptoms from mild reactions to severe anaphylaxis. An egg-free diet remains the only management approach for egg allergy. Therefore, individuals and families living with egg allergies rely heavily on allergen statements on packaged food products for informed food choices. Currently, no labeling regulations exist for unintentionally introduced allergens, posing risks to consumers with egg allergies. Therefore, it is critical to have an accurate and reliable detection method in allergen control and management to determine the concentration of total protein from allergenic food sources. Traditional enzyme-linked immunosorbent assays are routinely …

Phylogenetic And Biogeographic Patterns Of Devonian Proetid Trilobites, Katherine Jane Jordan

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

Ecological disruption events such as mass extinctions can result in the permanent alteration in clades and ecosystems. A pivotal time of change during the history of life on Earth can be seen in the Devonian Period. During this time, major transitions in marine and terrestrial system resulted in a different world at the end of the period in comparison to the beginning. One such group most heavily impacted were trilobites. Trilobites were reduced to one order by the end of the Devonian: Proetida. My dissertation focuses on phylogenetic, biogeographic, and paleocommunity patterns of this group, known as the last of …

Online Course Development With University Extension And Industry Experts, Kelsey L. Mccullough

Applied Science Program: Theses

Project Background

While pursuing my college degrees, the highest impact classes have been filled with applications that I understood as being relevant at the time and have used within my career, had hands-on experiences, and included influential interactions with professionals. Taking this idea forward to course development as an online instructor, I know that creating and adapting college classes to be centered on key aspects of the agricultural industry will add to the education quality of the program and the college experience. This paper will describe my first attempt at this model of partnering with academic and industry experts to …

Microbial Transfer And Cross-Contamination In Milling Facilities And Pathogen Survival In Milled Products And Baking Mixes, Aryany Leticia Peña-Gomez

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Wheat-based products, traditionally considered low-risk due to their low moisture content, have been involved in numerous foodborne outbreaks in recent decades. Salmonella and Shiga toxin-producing Escherichia coli (STEC) present in these products have caused significant numbers of hospitalizations and massive product recalls. The microbiological quality of flour is highly dependent on the incoming wheat, which is vulnerable to contamination from field to milling. Once pathogens are present in flour, they can survive for extended periods. Implementing strategies to mitigate the risk of pathogen contamination throughout the wheat processing chain is critical.

This study evaluated the distribution of E. coli …

The Effect Of Fat Content On The Inactivation And Recovery Of Listeria Spp. In Ready-To-Eat Foods After High Pressure Processing, Yhuliana Kattalina Niño Fuerte

Department of Food Science and Technology: Dissertations, Theses, and Student Research

High-pressure processing (HPP) is recognized by the United States Department of Agriculture Food Safety and Inspection Service (USDA FSIS) as a post-lethality treatment to control Listeria monocytogenes in ready-to-eat (RTE) meat and poultry products. A scoping review of 603 journal articles, which ultimately was narrowed down to 16 articles, revealed that the efficacy of HPP varies with fat content. The studies demonstrated that L. monocytogenes inactivation by HPP tends to be lower in RTE meats with greater than 5% fat content, compared to products with lower than 5% fat. The wide range of HPP parameters used in these studies …

Information About Honey Fraud: Implications Of Information Choice For Consumer Behavior, Christopher R. Gustafson

Cornhusker Economics

The study highlights that standard research practice—exposing participants to information—may not capture what will happen outside of the lab when people have a choice about what to read, view, or do with their time. While we found that having participants read about honey fraud significantly shifted their willingness to pay for local and domestic versus imported honey, we did not find those changes when people were able to select a text to read.

The implications of these findings extend beyond the issue of honey fraud to broader contexts of food safety, nutrition, and production techniques. While people have preferences for …

Aposematic-Habitat Correlation In Nearctic Species Of Episyron Schiødte (Hymenoptera: Pompilidae: Pompilinae: Pompilini), Frank E. Kurczewski

Insecta Mundi

Three Nearctic species of Episyron Schiødte (Hymenoptera: Pompilidae: Pompilinae: Pompilini) were examined morphologically, geographically, and ecologically with intent to infer an aposematic correlation with habitat type, protarsal digging rake morphology, and host spider association. Episyron quinquenotatus quinquenotatus (Say) and E. conterminus cressoni (Dewitz), two subspecies with extensive aposematic markings and more and longer protarsal comb spines, were associated with bare or sparsely vegetated sandy soils near water courses. Episyron biguttatus biguttatus (Fabricius), with few aposematic markings and less and shorter protarsal comb spines, was associated with more densely vegetated terrain and gravelly and loamy soils. Three subspecies of Anoplius …

Revision Of Trachyderines Related To Sphaenothecus From North America With Description Of Three New Genera, And New Species Of Lophalia Casey, 1912, Mannophorus Leconte, 1854, And Ischnocnemis Thomson, 1864 (Coleoptera: Cerambycidae: Cerambycinae: Trachyderini), Bryan K. Eya

Insecta Mundi

The genera Lophalia Casey, 1912, Mannophorus LeConte, 1854 and Ischnocnemis Thomas, 1864 (Coleoptera: Cerambycidae: Cerambycinae: Trachyderini) are recharacterized by providing additional morphological features to enhance the delineation of these genera. Two species, Lophalia cribricollis Bates, 1892 and Ischnocnemis luteicollis (Bates, 1885), are transferred to a new genus Lophaliamorpha Eya with Lophaliamorpha luteicollis (Bates) new combination as the type species. Ischnocnemis skillmani Chemsak and Hovore, 2010 is transferred to a new genus Paramannophorus Eya with Paramannophorus skillmani (Chemsak and Hovore) new combination as the type species. A new genus Microteroschema is created to accommodate two additional species from Mexico: Microteroschema parvum …

An Analysis Of The Genus Aleyrodes Latreille (Hemiptera: Sternorrhyncha: Aleyrodidae) In California, With Three Synonymies, Natalia Von Ellenrieder, Raymond J. Gill

Insecta Mundi

Abstract

Based on the examination of an extensive series of specimens and available type material, three out of the six species of Aleyrodes Latreille (Hemiptera: Sternorrhyncha: Aleyrodidae) described from California, A. diasemus Bemis, 1904, A. essigi Penny, 1922, and A. osmaroniae Sampson, 1945, are newly synonymized under A. spiraeoides Quaintance, 1900. The species of Aleyrodes reported from California are keyed and diagnosed based on characters from puparia and male genitalia, and character variability is documented and illustrated.

Resumen

Basado en el examen de una extensa serie de especímenes y material tipo disponible, tres de las seis …

A New Species Of Gaindaphodius Král And Mencl From Nepal (Coleoptera: Scarabaeidae: Aphodiinae), Stefano Ziani

Insecta Mundi

A new species from Nepal, Gaindaphodius marigold (Coleoptera: Scarabaeidae: Aphodiinae), is described, illustrated and compared with G. gainda Král and Mencl, 2024, the only other species in the genus Gaindaphodius Král and Mencl, 2024.

Ideas For Estate And Transition Planning: Gifting Ownership, Jessica J. Groskopf

Cornhusker Economics

For many farm and ranch families, bringing children or grandchildren into the operation is the ultimate goal. Successfully bringing additional family members into the operation may require some creativity as all parties need to maintain a viable standard of living. This article is part of a series that will highlight ideas and tactics for bringing another family member into the operation. If this is the first article you are seeing in this series, I would encourage you to go back to the for background and additional guidance.

A strategy that is gaining popularity is the gifting of shares or a …

Exploring Chilling Stress And Recovery Dynamics In C4 Perennial Grass Of Miscanthus Sinensis, Karolina Sobańska, Monika Mokrzycka, Martyna Przewoźnik, Tomasz Pniewski, Katarzyna Glowacka

Department of Biochemistry: Faculty Publications

The increasing cultivation of perennial C4 grass known as Miscanthus spp. for biomass production holds promise as a sustainable source of renewable energy. Unlike the sterile triploid hybrid of M. × giganteus, which cannot reproduce through seeds, M. sinensis possesses attributes that could potentially address these limitations by effectively establishing itself through seed propagation. This study aimed to investigate how 18 genotypes of M. sinensis respond to chilling stress and subsequent recovery. Various traits were measured, including growth and biomass yield, the rate of leaf elongation, and a variety of chlorophyll fluorescence parameters, as well as chlorophyll …