Digital Commons Network^™

Stories Of Motivation And Values Of Small-Scale Farmers In Jamaica And The United States, Raquel Taylor

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

Small-scale farmers add to global and local food systems through various means such as connecting communities to local food and support economies. Small-scale farms can address issues related to food and nutritional security. However, farming can be a challenging career to engage in, especially for those who are small-scale farmers. Matters related to succession, higher paying off-farm employment, policies, and more can make it challenging to engage in farming. Leaving the question of what would motivate someone to engage in small-scale farming. Motivation can be viewed through multiple lenses; this study chose to use self-determination theory to understand the motivations …

Impact Of Plant Defenses And Aphid-Associated Microbes In Modulating Sorghum–Sugarcane Aphid Interactions, Edith Ikuze

Department of Entomology: Dissertations, Theses, and Student Research

Sorghum (Sorghum bicolor) is a vital cereal crop globally, facing challenges from invasive pests such as the sugarcane aphid (SCA; Melanaphis sacchari). To elucidate mechanisms of sorghum resistance to SCA, we examined the role of plant defenses and the influence of aphid-associated microbes in modulating sorghum defenses. Lignin is a complex heterogenous polymer present in nearly all plant cell walls that plays a critical role in protecting plants from various stresses. In this study, we investigated the role of the caffeoyl coenzyme-A O-methyltransferase (CCoAOMT), one of the core enzymes in monolignol biosynthesis pathway that leads to lignin …

Genome-Scale Metabolic Modeling Of Chitin-Degrading Microbial Systems, Aimee Kristin Kessell

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

As a major component of fungal cell walls and exoskeletons of invertebrates, chitin is widespread in soils, constituting the second most abundant biopolymer in nature. Composed of N-acetyl-D-glucosamine chains, it serves as a vital source of nutrients, including both carbon and nitrogen, for the growth of microorganisms. A solid understanding of the microbial degradation of chitin is critical for predicting their impacts on biogeochemical cycling in soil ecosystems. Organisms that degrade biopolymers (degraders) produce energetically expensive extracellular enzymes to break down complex organic carbons into simpler labile forms that are sharable with other species, including those that do not contribute …

Sarcopenia And The Importance Of Resistance Training And Protein-Rich Diets For Prevention Of Muscle Loss In Older Adults: A Literature Review And Informational Pamphlet, Madison Steele

Honors Program: Senior Projects (Public)

The growing prevalence of sarcopenia among older adults as well as youths has prompted further research aimed at developing effective preventative measures and treatment plans. Sarcopenia is often thought to occur solely due to aging, but several other factors contribute to progressive muscle loss. Previous research studies have found an effect of physical activity and dietary protein levels on the risk of developing sarcopenia as well as its onset age. This study aims to review existing knowledge in the field to compile an extensive list of sarcopenia causes and methods of prevention. The main causes identified in this review are …

Determining The Impacts Of Corn Silage Mixing Ratios On Hydrogen Production From Beef Cattle Manure, Katya Faber-Quimby

Honors Program: Senior Projects (Public)

With global warming becoming an increasingly serious threat and a growing population requiring additional energy resources, interest in the production of clean energy from the agricultural sector has surged in popularity. Biohydrogen, also known as green hydrogen, is H₂ that has been produced using renewable energy, such as from agricultural byproducts or waste materials. It presents a promising alternative to nonrenewable resources due to its high potential for energy storage and lack of carbon emissions when used. Cattle manure has been explored as a resource for the production of biohydrogen. Selecting for hydrogen-producing microbes in the manure serves the …

Inhibition Of Foxo Induces Oxidative Stress In Osteosarcoma, Kai K. Brown

Theses (2016-Present)

Redox homeostasis is a balance between reactive oxygen species (ROS) generation and neutralization by antioxidants. Oxidative stress (OS) results when the generation of ROS exceeds the neutralizing capacity of endogenous antioxidants. Reactive oxygen species are generated during cellular processes such as mitochondrial activity or metabolism of drugs. Expression of endogenous antioxidants is driven by redox-sensitive transcription factors; therefore, redox-sensitive transcription factors are essential for the maintenance of cellular redox homeostasis. There are several redox-sensitive transcription factors that contribute to the expression of endogenous antioxidants. These redox-sensitive transcription factors include nuclear factor erythroid 2-related factors (Nrf-2), hypoxia-inducible factor (HIF), activator protein-1 …

Biosorption Of Lithium Using Microbes, Adebola Daisy Olade

Theses (2016-Present)

Lithium (Li) is a very valuable metal that is used across several industries including ceramics, glass, batteries, pharmaceuticals, and polymers. However, in recent years, the global demand for Li and its market price have increased considerably, due to its application as a critical component in the production of rechargeable Li-ion batteries and energy storage systems that are used in electric vehicles and a variety of electronic devices. Although Li occurs as a mineral in hard rocks and salt brines, substantial amounts are found in our environment as part of industrial wastes and oil-field wastewaters. Despite its importance, Li is also …

Impact Of Water Combined Wet Ball Milling Extraction And Functional Evaluation Of Dietary Fiber From Papaya (Carica Papaya L), Guihun Jiang, Kashif Ameer, Karna Ramachandraiah, Xiaoyu Feng

School of Medicine Faculty Publications

This study evaluates the structural, physicochemical, functional and rheological properties of papaya dietary fibers (DFs) extracted by alkaline, water and combination of water/wet ball milling. The particle size of DF subjected to water/wet ball milling (WB-DF) was considerably reduced compared to DF extracted by water (W-DF) or alkaline (AL-DF) methods. WB-DF in comparison AL-DF increased the water holding capacity (WHC) by 4.1 folds, oil holding capacity (OHC) by 1.7 folds and water swelling capacity (WSC) by 2.6 folds. WB-DF also improved the cholesterol adsorption capacity (CAC), glucose adsorption (GAC), nitrite-ion adsorption capacity (NIAC) and antioxidant activity. The FT-IR spectra displayed …

Genome-Wide Association Study/ Genomic Prediction Of Cowpea Seed Protein And Black Seed Coat Color In Cowpea, Yilin Chen

Graduate Theses and Dissertations

Cowpea (Vigna unguiculata [L.] Walp) is a crucial crop in many regions, serving as a vital protein source for humans and livestock. Addressing the need to enhance its nutritional quality and make it easier to cultivate cowpeas of specific colors, this study utilized genome-wide association studies (GWAS) to identify markers associated with protein content and seed coat color patterns in cowpea.

In the protein content study, a GWAS was conducted on 161 cowpea accessions using 110,155 high-quality single-nucleotide polymorphisms (SNPs). Seven significant SNP markers were identified, all located at a locus on chromosome 8 associated with the gene Vigun08g039200, enhancing …

Avoidant/Restrictive Food Intake Disorder Prevalence Is High In Children With Gastroparesis And Functional Dyspepsia, Isha Kaul, Helen Burton-Murray, Salma Musaad, Yiming Mirabile, Danita Czyzewski, Miranda A L Van Tilburg, Andrew C Sher, Bruno P Chumpitazi, Robert J Shulman

Children’s Nutrition Research Center Staff Publications

BACKGROUND: Avoidant/restrictive food intake disorder (ARFID) prevalence in children with gastroparesis (Gp) and/or functional dyspepsia (FD) is unknown. We aimed to identify ARFID prevalence and trajectory over 2 months in children with Gp, FD, and healthy children (HC) using two screening questionnaires. We also explored the frequency of a positive ARFID screen between those with/without delayed gastric emptying or abnormal fundic accommodation.

METHODS: In this prospective longitudinal study conducted at an urban tertiary care hospital, patients ages 10-17 years with Gp or FD and age- and gender-matched HC completed two validated ARFID screening tools at baseline and 2-month follow-up: the …

The Functional Dynamics Of Bacterial Communities In Relation To Environmental Selection And Host Health In A Pitcher Plant Model System, Jessica Rae Bernardin

Boise State University Theses and Dissertations

Our research investigates the function and composition of microbial communities across various conditions, shedding light on microbial community dynamics and plant-microbe interactions. Despite the crucial role microbes play in Earth's ecosystems, many questions remain about how microbiomes function and their direct impact on host health.

The first chapter explores the links between bacterial community function and the growth of purple pitcher plants (Sarracenia purpurea). We introduced three distinct bacterial communities into sterile pitchers to assess their effects on plant health. Different bacterial functions influenced plant traits, with communities rich in decomposition and secondary metabolite production traits leading to significantly larger …

Psychology Of Athletes: Impact Of Injuries On Mental Health, Caitlin Rainey

Whittier Scholars Program

This article aims to contextualize the importance of understanding injuries in athletics and how those injuries impact mental health. With such a high prevalence of injuries in athletics, most studies analyze the physical implications on the athlete. It is vital that mental well being is studied as much as physical health throughout the injury and rehabilitation process. This study reviewed previous literature on the social impacts of team sports, psychological and social implications of injury, the impact of residual pain, and finally the process of retirement. A survey was also conducted at a small liberal arts college in Southern California …

Characterizing The Role Of Pa5189 Of Pseudomonas Aeruginosa In Deletion And Overexpression Mutants, Seh Na Mellick

Theses/Capstones/Creative Projects

In the context of rising multidrug resistance in biofilm-forming pathogens like Pseudomonas aeruginosa, this study investigates the role of the understudied transcription factor PA5189 in antibiotic resistance and biofilm formation. PA5189 deletion and overexpression mutants were created in a parent P. aeruginosa strain using pEX18Tc-based recombinant suicide vectors, with genotypic verification of putative triparental conjugants achieved through restriction digestion and PCR. The study revealed that PA5189 overexpression significantly increases resistance to commonly used broad spectrum antibiotics such as ciprofloxacin and imipenem. Additionally, differential expression of PA5189 was found to notably affect biofilm formation, with variations contingent on the nutrient …

Survey Of The Bolctes From Fish River Nature Preserve, Noah T. Nelson

Honors Theses

Boletes are a special kind of mushroom inside of the Kingdom Fungi that are distinguished from other mushrooms by their uniquely pored hymenium, as opposed to gills. Many boletes are ectomycorrhizal, meaning they are mutualists with vascular plants, and thus beneficial to the overall health of the terrestrial ecosystem. Some are well-known for their edibility and are of economic importance. In the United States 59 genus-level clades comprising 290 operational taxonomic units have been reported. The southeastern US and Gulf Coast regions however are less researched and recorded for their mushroom ecology. In Alabama, only 56 bolete species have been …

Evaluation Of Late Season Potassium Applications To Arkansas Soybean, Carrie Ortel

Graduate Theses and Dissertations

Potassium (K) deficiency is one of the most important yield limiting factors in Arkansas soybean (Glycine max (L.) Merr.) production, although there are recently improved diagnostic and management opportunities available. However, several questions regarding the successful implementation of in-season K management in soybean production remain. Therefore, the research objectives were to (a) delineate the relationship between drought stress and K deficiency on soybean vigor, (b) identify the spatial dependencies of leaf-K concentrations at the production scale, (c) develop a leaf sampling protocol, (d) calibrate the fertilizer-K rate needed to correct varying levels of K deficiency at 15, 30, and …

Molecular Characterization Of Stress Response In Western Honey Bee (Apis Mellifera), Faizan Tahir

Master's Theses

Honey bees are incredibly important for the reproduction of flowering plants and the sustainability of agricultural ecosystems. However, they face various stressors such as pesticides, pathogens, habitat loss, and climate change. Extensive research has been conducted to understand how bees respond to these stressors. Scientists have discovered that honey bees exhibit complex physiological and behavioral responses to stress at individual and colony levels. Stress can have a significant impact on their immune function, foraging behavior, and reproductive success (Decourtye et al., 2010). Understanding bee responses to stress is crucial for several reasons. Firstly, honey bees are vital for the pollination …

The Assessment Of Autonomic Function In Young Adults With An Elevated Risk Of Metabolic Syndrome, Ta'quoris Newsome

Master's Theses

Metabolic syndrome (MetS) is a complex medical condition defined by the co-occurrence of multiple cardiometabolic risk factors. Despite the well-defined profile of autonomic function in individuals with MetS, autonomic function in those with an elevated risk of developing MetS remains unclear. Our study aimed to shed light on the progression of cardiometabolic disease and its impact on autonomic function. To investigate, twenty participants, ten of whom were classified as having an elevated risk of developing MetS based on identification of risk factors using NCEP ATP III criteria, completed a two-visit study protocol. In the second visit, spontaneous cardiovagal baroreflex sensitivity …

Rare Case Of Open Comminuted Scaphoid Fracture Dislocation: Treatment With Free Bone Graft And Locking Plate, Makoto Fukuda, Masahiro Miyashita, Masataka Yasuda

Children’s Nutrition Research Center Staff Publications

To the best of our knowledge, there are no reports in the literature of an open comminuted scaphoid fracture dislocation. We present such a rare case. The case report illustrates the case of a 58-year-old right-handed press operator who injured his left wrist when his hand got caught in a press machine. He received initial treatment at another hospital and was subsequently referred to our hospital. Eight days after the injury, surgery was performed under the brachial plexus block. Successful bone fusion was achieved through volar locking plate fixation, primary free bone grafting from the radius, and Kirschner wire fixation. …

Associations Between Gut Microbiome Metabolomics And Endometriosis Risk, Progression, And Non-Invasive Diagnosis: A Review, Marlee Sanders

Honors Theses

Endometriosis is a gynecological condition that affects 1 in 10 women of reproductive age, is characterized by growth of endometrial tissue outside of the uterus, and encompasses metabolic, immunologic, and endocrine dysfunction. Despite its significant impact, endometriosis remains inadequately studied within the realm of women's health, emphasizing the crucial need for innovative approaches in the analysis and diagnosis of this complex condition. The cause of endometriosis is unknown however it could be influenced by genetics, environmental factors, diet, lifestyle, and notably composition of the gut microbiome. Recent scholarly interest has sparked inquiries into the correlations between endometriosis and the gut …

Irt-Based Irrigation Scheduling And Dry Bean Crop Water Productivity Under Different Irrigation Scenarios In The Nebraska High Plains, Angie Gradiz

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

Irrigation plays a critical role for crop production in western Nebraska of the United States, where crop evapotranspiration often exceeds in-season precipitation. This study investigated the impacts of different irrigation treatments on yield and key physiological parameters of dry edible beans grown in semi-arid western Nebraska during the 2022-2023 growing seasons. Seven irrigation levels (0%, 25%, 50%, 75%, 100%, 125%, 150%) of the fully irrigated treatment (FIT), were applied using a Variable Rate Irrigation (VRI) Linear-Move Sprinkler System. Additionally, an eighth treatment was scheduled based on measurement from infrared radiometry thermometers (IRT) to evaluate the performance of the two-source energy …

Toxicological Effects And Treatment Of Accidental Ingestion Of Simparica Trio® In Felis Catus: An Investigative Review, Aussia M. Stander

Honors Program: Senior Projects (Public)

Simparica TRIO^®, a canine endectocide manufactured by Zoetis, contains sarolaner, moxidectin, and pyrantel pamoate salt in an orally administered chewable tablet. These compounds are all toxic to both cats and dogs in sufficient amounts. As Simparica TRIO^® rises in popularity among pet owners, Felis catus (felines, cats) in multi-pet households (households with both cats and dogs) are at increased risk of overdosage and toxicosis from accidental ingestion of Simparica TRIO^® due to their smaller weight.

Simparica TRIO^® is not for feline use and little literature exists on the symptoms of and treatment for accidental ingestion …

Evaluation Of Critical Weed-Free Period For Three Sweetpotato (Ipomoea Batatas) Cultivars, Emmanuel G. Cooper, Stephen L. Meyers, Jeanine Arana, Katherine Jennings, Ashley Adair, Kevin D. Gibson, William G. Johnson

Department of Horticulture & Landscape Architecture Faculty Publications

Sweetpotato [Ipomoea batatas (L.) Lam.] is a staple crop that provides nutritional benefits to humans globally, but it is subject to yield loss when competing with weeds, especially during the early stage of establishment. Yield loss can vary widely based on the cultivar, production environment, weed species, and management techniques. To address this challenge, we conducted field research at the Samuel G. Meigs Horticulture Research Farm, Lafayette, IN, and at the Southwest Purdue Agricultural Center, Vincennes, IN, in 2022 to determine the effect of sweetpotato cultivar on the critical weed-free period. The experiment was a split-plot design, with weed-free interval …

Using Additional Measures Of Handgrip Strength To Predict Aerobic Capacity In Wheelchair Users, Eric Naugle

All NMU Master's Theses

Manual wheelchair users have been shown to have low physical capacity and impaired ability to perform activities of daily living. Current tests and protocols for assessing physical capacity in wheelchair users have specific boundaries. Measuring handgrip strength (HGS) with electronic handgrip dynamometers has been shown to be a reliable measure of muscle function and a convenient assessment of overall muscle strength. This study aimed to determine the correlation of maximal HGS, HGS rate of force development, HGS fatigability, HGS isometric control, and HGS asymmetry to a six-minute wheelchair propulsion (6MPT) test in ambulatory young adults. Thirty-four recreationally active ambulatory individuals …

Comparing The Effectiveness Of Different Forms Of Vitamin E Supplementation (Liquid Vs. Powder) On Serum Alpha-Tocopherol Concentrations In Developing Horses, Emilia Fong-Gallagher

Honors Scholar Theses

Vitamin E is an essential antioxidant in equines that has a significant role in the nutritional requirements of horses to keep bodily systems functioning at optimal levels. Vitamin E deficiency is often associated with serious incurable neuromuscular diseases such as equine motor neuron disease and equine protozoal myeloencephalitis. Many horses stabled in urban areas are often deficient due to the lack of adequate grazing time as their natural source of vitamin E is from grass, and therefore should receive supplementation. This study evaluated the effectiveness of different forms of Elevate vitamin E supplement on the serum alpha-tocopherol concentrations in fourteen …

Genetics Of Lrg1 And Its Association With The Cardiometabolic Risk Traits In Mexican American Children And Adolescents, Aaron Rene Reyna

Theses and Dissertations

Leucine-rich alpha-2-glycoprotein 1 (LRG1) has become a major topic of research due to an increasing number of studies demonstrating its unique role in the pathogenesis of multiple human diseases including diabetes and cardiovascular disease. LRG1 has recently been identified as an adipokine, a signaling molecule secreted by adipose tissue. Furthermore, it has been correlated with intercellular signaling that promotes diet-induced hepatosteatosis and insulin resistance in mice. In this study, LRG1 serum concentrations were measured in a family-based cohort of 571 non-diabetic Mexican American children and adolescents aged 6-17 years old (mean age = 11.76 years and females = 48.2%) to …

Development And Application Of Environmental Dna (Edna) Techniques To Detect Rough-Footed And Yellow Mud Turtles: A Seasonal Field Study To Detect Turtle Edna, Sakib Tahmid Rishan

Theses and Dissertations

The application of environmental DNA (eDNA) has improved the ability of humans to detect the existence and geographical distribution of aquatic organisms. The present study highlights the development and application of eDNA techniques to detect rough-footed mud turtles and yellow mud turtles in different areas in Texas. Both mud turtle species were successfully detected in lakes/resacas using direct eDNA sampling techniques. Moreover, passive eDNA sampling techniques were conducted using different membrane filters to detect mud turtle species. The findings indicated that only the mixed cellulose esters (MCE) filter membranes effectively identified eDNA of yellow mud turtles in the fall, but …

Effects Of Nitrogen Or Phosphorus Depletion On Lipid Production In Bracteacoccus Sp. And Tetrastrum Sp., Cassandra J. Po

Theses and Dissertations

As global energy demands have risen in the past decades, various species of microalgae have been chosen and used as sources of lipids for third-generation biofuel. I selected two species of green microalgae, Bracteacoccus sp. and Tetrastrum sp., from isolates from South Texas to determine their potential as sources of biofuel. For comparison, Chlamydomonas reinhardtii was used as a model organism. To evaluate lipid productivity under different nutrient regimens, the microalgae were grown in nutrient-replete growth media until the population had reached the end of the logarithmic phase (roughly 14 days), and then transferred into growth media depleted of nitrogen …

Spatial Ecology Of Mule Deer Migrations From Grand Teton National Park And The Teton Range, Justin K. Schwabedissen

All Graduate Theses and Dissertations, Fall 2023 to Present

The Greater Yellowstone Ecosystem hosts several of the longest, fully intact ungulate migrations remaining in the continental United States. However, expanding development and an increasing human footprint continue to truncate migratory routes. While the endpoints are often a seasonal range on protected lands, these migration corridors frequently cross other jurisdictional boundaries, including large tracts of private or multiple-use lands, with varying levels of protection. Thus, it is critical resource managers understand the dynamics of migratory movements to define population-level corridors and prioritize appropriate conservation strategies. Mule deer in Wyoming have been documented traveling long distances between summer and winter ranges; …

Morphological And Physio-Biochemical Responses And Gene Expression Analyses Of Landscape Plants Under Salinity Stress, Asmita Paudel

All Graduate Theses and Dissertations, Fall 2023 to Present

Soil salinity is a significant global issue that adversely impacts the growth and development of landscape plants. One of the effective strategies to prevent salinity damage to landscape plants is to cultivate species that are tolerant to the prevailing salinity levels. Salinity tolerance varies among plant species and cultivars. Therefore, this research aimed to investigate the salinity tolerance of nine landscape plants [Albizia julibrissin (mimosa tree), Arctostaphylos uva-ursi (kinnikinnick), Cercocarpus ledifolius (curl-leaf mountain mahogany), Cercocarpus montanus ‘Coy’ (alder-leaf mountain mahogany), Penstemon barbatus ‘Novapenblu’ (rock candy blue^® penstemon), Penstemon strictus ‘Rocky Mountain’ (rocky mountain beardtongue), Punica granatum ‘Wonderful’ (pomegranate), …

Processes For Improved Variable Rate Irrigation And Nitrogen Within Potato-Wheat-Wheat Cropping Systems, Elisa A. Flint

All Graduate Theses and Dissertations, Fall 2023 to Present

Proper irrigation and nutrient management are vital for optimal crop production within agricultural fields. Improving irrigation and nutrient application through precision agriculture is necessary to conserve the limited resources available, while improving yield and quality of crops produced through such a system. Variable rate irrigation (VRI) and variable rate nitrogen are systems used to apply water and nitrogen more precisely to agricultural fields to reduce runoff, deep percolation, leaching, and other negative impacts of over application, while providing the optimal rates to produce maximum yields. However, the processes to utilize these systems have proven to be more difficult than expected, …