Digital Commons Network^™

Nitrogen Application Timing And Cereal Rye (Secale Cereale L.) Cover Crop Influence Greenhouse Gas Emissions, Graig Reicks

Electronic Theses and Dissertations

Dryland contributions to greenhouse gas (GHG) emissions are increased by N fertilizer applications and high soil water contents. Fertilizer timing and spring growth of cover crops prior to cash crop planting were investigated in separate studies to examine impacts on overall GHG emissions using a near continuous measurement system. There was a significant interaction between N fertilizer rate (0 vs. 224 kg N ha-1 surface-applied as urea) and application date (p= 0.01) for CO2 emissions. This interaction occurred because N fertilizer increased CO2 emissions by 35% for the 21 d interval following early spring application. When application was delayed until …

Developing Machine Learning Models For Selection Of Management Zones, Sravanthi Bachina

Electronic Theses and Dissertations

Soil sampling and analyses play a crucial role in optimizing nutrient management and enhancing crop productivity. However, collecting representative samples across diverse landscapes is challenging due to knowledge gaps about spatial variability of soil properties, large fields, multiple samples, and analysis costs. Collecting soil samples based on the management zones can help farmers gather precise information about soil properties with fewer samples. Recent developments in precision agriculture and machine learning. This study aimed to develop machine learning models that can learn, analyze, and refine landscape and soil properties data for automated selection of soil sampling zones and generating prediction maps. …

The Effects Of Degradation On Pla When Combined With Additives In A Single Screw Extruder, Jack Koester

Electronic Theses and Dissertations

No abstract provided.

Species Distribution Modeling Of Aquilegia Brevistyla (Ranunculaceae): A Critically Imperiled Black Hills Disjunct Species, Eric Daniel Puetz

Electronic Theses and Dissertations

Unchecked human activity is contributing to rising levels of greenhouse gas emissions, changes in land use, altered disturbance/fire regimes, spread of invasive species, and loss of biological diversity and related breakdown of ecosystem services. Additionally, climatic shifts may lead to phenological mismatches between species and their environments if these changes outpace a species’ ability to adapt or migrate to a more suitable habitat. Isolated mountain populations are particularly threatened by unpredictable climatic conditions, as they may have limited migration corridors and often lower levels of genetic diversity to move or adapt, respectively. As these negative feedbacks compound on the landscape, …

Mechanical Testing Of Novel Biopolymers For The Replacement Of Petroleum-Based Plastic Hay Bale Net Wrapping, Logan Wolf

Electronic Theses and Dissertations

The purpose of this thesis is to test biopolymers synthesized from oilseeds or produced from agricultural wastes for large bale net wrapping as a viable alternative to conventional petroleum-based plastics (PBP). The goal is to test and assess novel polymers to guide the synthesis of a benign biodegradable polymer. Biobased net wrapping will significantly reduce ingestion of PBPs in animals such as ruminants to improve digestive health and minimize cattle loss due to plastic disease. Biobased plastics will also achieve partial or complete breakdown shortly after service without depositing microplastics in the environment. This will reduce the risk of damage …

The Effects Of Temperature, Flooding, And Goose Feces Addition On Greenhouse Gas Emissions And Ammonification In Four High-Latitude Soils From Western Alaska, Jenna M. Ross

Electronic Theses and Dissertations

The large carbon (C) stock of wetlands is vulnerable to climate change, especially in high latitudes that are warming at a disproportional rate. Likewise, low-elevation Arctic coastal areas will flood more frequently under climate change and sea-level rise, which may alter goose herbivory and fecal deposition patterns if geese move inland. While temperature, flooding, and feces impact soil C emissions, their interactive effects have been rarely studied. Here, I explore the impact of these interactions on CO2 and CH4 emissions and nitrogen (N) mineralization (ammonification) in soils collected from four plant communities in the Yukon-Kuskokwim (Y-K) Delta, a high latitude …

Movement Ecology Of Paddlefish And Walleye Reveal The Importance Of Continued Interjurisdictional Management In Riverine And Lacustrine Systems, Kaitlyn Bearden

Electronic Theses and Dissertations

Fisheries systems function at broad spatial and temporal scales. Fishes within these systems are often highly mobile and move to locate adequate habitat, to feed and reproduce. As individuals navigate their environment, they potentially cross regulatory boundaries (state or federal) and or encounter physical barriers such as dams. Regulatory boundaries may not physically impede fish movement, but they are visible to fisheries managers thus the fishes within them may be vulnerable to varying management and harvest regulations. Physical boundaries (e.g., dams) are also particularly problematic for highly mobile species in large river systems. In chapter two, I documented that apparent …

Feeding Isoacids To Swine: Inclusion Level And Interactions With Dietary Fiber And Protein, Angie Patricia Benavides Infante

Electronic Theses and Dissertations

In animal production, research is continually being carried out into implementing new feeding strategies, such as incorporating new alternative ingredients or additives that improve the quality of the diet, reduce the cost of diets, or have effects on intestinal health. The inclusion of branched-chain volatile fatty acids has been investigated in ruminants, and it has been found that a diet supplemented with BCVFA increases fiber digestibility as well as increases cellulolytic bacteria in the rumen. There is little information about the possible effects on pigs supplemented with BCVFA. According to this, the first study aims to evaluate the optimal inclusion …

Effects Of Low-Cost, Low-Tech Tools For Riparian Restoration On Prairie Streams In Western South Dakota, James Andrew Joseph Bolyard

Electronic Theses and Dissertations

Despite making up less than two percent of the overall landscape in the arid and semi-arid western US, riparian areas are a crucial resource for agriculture, livestock, and wildlife. However, many have impaired function and reduced riparian cover. Low-Cost, Low-Tech Tools (LCLTT) are a subset of Process-Based Restoration (PBR) used for riparian restoration that were chosen for their cost-effectiveness and minimal technical requirements. LCLTT has been tested in mountainous areas of the western US but only recently implemented in the Northern Great Plains (NGP). Given their novelty as an approach toward restoration for the region, professional restoration and landowner communities …

Near-Real-Time Monitoring Of Crop Progress At Field Scales By Fusing Observations From Both Polar-Orbiting And Geostationary Satellites, Yu Shen

Electronic Theses and Dissertations

No abstract provided.

The Relationship Of Macronutrient Intake With Growth In Children With Type 1 Diabetes Mellitus, Jessica L. Freeling

Electronic Theses and Dissertations

Child growth, a sensitive metric of overall health, results from the intricate interplay of nature and nurture. While the importance of nutrition in child growth is well established, growth trajectories exhibit substantial individual variability, influenced by sex and age, and often characterized by nonlinear patterns. Inadequate nutrition or disease can hinder growth, with potential for recovery upon proper nutrition or acute disease resolution. However, chronic disease or persistent malnutrition may lead to permanent growth perturbation. Notably, before the advent of insulin, chronic stunting and wasting were hallmarks of Type 1 diabetes mellitus (T1DM), though the specific impacts under modern standard …

The Influence Of By-O-Reg+ Beef, An Oregano-Based Essential Oil Supplement, On Growth Performance, Carcass Traits And Meat Quality Of Finishing Beef Steers, Bergin Mackenzie Debruin

Electronic Theses and Dissertations

The objective of this thesis was to determine the influence of an oregano-based essential oil (OEO; By-O-Reg+ Beef), on growth performance, carcass traits, and meat quality of beef steers finished in an all-natural program. Yearling steers were allotted to 16 pens (n = 8 pens per treatment, 8 steers per pen). Treatments included: 1) control (CON) fed no oregano-based essential oil and 2) group fed 4 g/steer daily of By-O-Reg+ Beef. Steers were harvested on day 149 of the feeding period. Standard carcass data was collected and instrumental color (L*, a*, b*) was recorded. Strip loins were collected from a …

Spatial Variation Of Microbial Communities In Aquatic Ecosystems In The Southeastern United States, Jordan Heiman

Electronic Theses and Dissertations

Spatial variation in bacterial communities, or bacterial biogeography, is important for understanding the role of microorganisms in biogeochemical cycles. In the Southeastern United States, aquatic ecosystems are highly biodiverse and imperiled, yet few studies have investigated bacterial biodiversity and biogeography in this region. In this dissertation, I aimed to understand the bacterial biogeography in aquatic ecosystems in the Southeastern United States and how this spatial variation relates to abiotic factors in these ecosystems. To do this, I analyzed biogeographic patterns in bacterial communities from three distinct types of aquatic ecosystems (rivers, a lake, and beaches) and conducted a microcosm experiment …

Open-Source Frameworks For Groundwater Analytics: Advancing Machine Learning Workflow Development And Deployment, Sarva Pulla

Electronic Theses and Dissertations

This dissertation introduces three innovative tools to advance groundwater analytics: the GRACE Downscaler, Synthetic Timeseries Generator, and a lightweight web-based service for deploying machine learning and physical models. These tools address critical challenges in groundwater management by enhancing the local applicability of GRACE satellite data, overcoming data scarcity through synthetic generation, and simplifying the deployment of complex hydrological models. The GRACE Downscaler provides a reproducible workflow for regional groundwater analysis, while the Synthetic Timeseries Generator creates opportunities for model development in data-poor regions. The web-based service demonstrates how advanced models like MODFLOW can be made accessible for rapid simulations and …

Demarginalizing Bede's Margins: A Digital Codicological Reassessment Of The Relationship Between Marginalia And Body Matter In Cambridge, Corpus Christi College Ms 41, James Nicholas Sumrall

Electronic Theses and Dissertations

The scribal activity in the margins of the eleventh-century Cambridge, Corpus Christi College MS 41 has long been acknowledged and studied, but rarely have scholars examined the relationship between the manuscript’s marginalia and its body text, an Old English translation of Bede’s Historia Ecclesiastica. As such, this thesis attempts to address this critical scholarly gap by evaluating key marginal texts of MS 41 in their original physical contexts. In the introduction and first chapter, a brief overview of the manuscript history of MS 41 and its five extant analogues is given. The second chapter focuses on the textual transmission, content, …

Student Informed Instruction: Vertical Non Permanent Surfaces, Cononiah L. Watson

Electronic Theses and Dissertations

I, an 8th grade mathematics teacher, have used vertical dry erase boards in my classroom for years to promote student engagement and perseverance after participating in a book study on Building Thinking Classrooms by Peter Liljedahl. Year after year, the implementation of this strategy was constantly refined based on research, other teachers’ experiences, and my perceived notions of students’ experiences while at the dry erase boards. I never, however, asked students to thoughtfully share their experiences. In this study, I introduce the method of student informed instruction to refine how I use vertical dry erase boards in my classroom. After …

Persuasion Knowledge In A Post-Truth Era, Emma Welch

Electronic Theses and Dissertations

Commenting on a world replete with conspiracy theories, fake news, and virality on social media, some have dubbed the era we are currently living in as the “post-truth” era, defined as “relating to or denoting circumstances in which objective facts are less influential in shaping public opinion than appeals to emotion and personal belief”. The post-truth era is said to affect how individuals make decisions, form opinions, and communicate with one another. Although many frameworks have emerged along the way that describe how consumers deal with persuasive communication, truthful or otherwise, emerging technology has added a new layer to the …

Regional Differences In The Adoption Of Automated License Plate Readers Among Police Departments, Dalton Lee Massingill

Electronic Theses and Dissertations

Since the 2000s, the adoption of License Plate Readers (LPRs) in the United States has steadily increased. Prior research has shown that agency characteristics (mainly size) strongly impact the likelihood of LPR usage. However, researchers have primarily examined larger police departments and used smaller samples in examining the adoption of LPRs. This study uses recent data from a nationally represented sample of law enforcement agencies to examine the relationship between agency geographical location and LPR usage. The current study extends past literature by examining the impact an agency’s geographical location has on LPR usage. Research has not studied if LPR …

Pi3k Signaling And Its Role In Cardiac Morphogenesis, Rabina Shrestha

Electronic Theses and Dissertations

The formation of the heart tube in vertebrates involves the coordinated movement of bilateral myocardial precursors to the midline, where they merge in a process known as cardiac fusion to form the primitive heart tube. While external influences from the anterior endoderm and the endocardium are known to be essential for cardiac fusion, intrinsic myocardial mechanisms are less understood. Here, we identify an intrinsic PI3K-dependent mechanism directing myocardial cells toward the midline during cardiac fusion. We found that inhibiting the PI3K pathway throughout the embryo using chemical inhibitors and injection of dnPI3K mRNA results in cardiac fusion defects. PI3K-inhibited embryos …

Isolation Of Novel Myxobacteria And Progress Towards Heterologous Expression Of Uncharacterized Secondary Metabolites, Andrew Ahearne

Electronic Theses and Dissertations

Myxobacteria, first observed by Roland Thaxter in the late 19th century, are known for their unique swarming behavior, complex fruiting body formation and biosynthetic potential. Myxobacteria are noted for their large genomes and the presence of numerous biosynthetic gene clusters (BGCs) that hint at their potential to produce novel metabolites with therapeutic properties. Isolation of myxobacteria utilizing E. coli and filter paper baiting yielded 20 myxobacteria isolated from rhizospheric soil samples in North America. Among these isolates, nine were identified as novel species, representing the genera Archangium, Myxococcus, Nannocystis, Polyangium, Pyxidicoccus, Sorangium, and Stigmatella. Comprehensive growth profiles, biochemical assays, and …

Imaginative Play In The Inculcation Of Creativity As An Intellectual Virtue, Annie Elisabet Gustafsson

Electronic Theses and Dissertations

Creativity, defined as the ability to generate original and innovative ideas and products, is widely valued yet not explicitly taught. This largely stems from the understanding that creativity cannot be cultivated through traditional methods like imitation or direct instruction, as such approaches contradict the essence of creativity itself. However, we must not write it off as unteachable. To help us better understand what can be done to teach creativity effectively, we must consider its character.

This paper offers a theory of creativity as an intellectual virtue, drawing on Linda Zagzebki’s components of virtue and aligning creativity with Aristotle’s phronesis and …

Infrasound From Tornadoes: Theory And Experiment, Bin Liang

Electronic Theses and Dissertations

Previous field experiments support the claim that a tornado can radiate discernible infrasound between 0.5−10 Hz. The physical mechanisms of tornado sound generation are still not fully understood although several potential mechanisms have been proposed. In this dissertation, a new mechanism based on vortex sound theory is examined analytically and numerically. Basically, rotation of the non-axisymmetric vorticity field in tornadoes can produce dominant low-frequency infrasound less than 2.0 Hz. This finding is based on a detailed analysis of calculating infrasound emitted from two numerical models of tornadoes using large eddy simulation (LES), called the baseline model and the eddy injection …

The Perceived Effects On The Motivation, Anxiety, And Online Language Learning Of Saudi Efl Learners During The Covid-19 Pandemic, Ali Hasan Alamry

Electronic Theses and Dissertations

Although many restrictions initiated by the COVID-19 pandemic are no longer imposed, massive changes across the globe have impacted online language learning afterward. Technology infrastructure, students' and teachers' digital literacy, and proper distance learning pedagogies were among the challenges of online learning during the pandemic. Nevertheless, valuable lessons can be learned from the pandemic to better handle online language learning classes in the future. Globally, increasing attention in the literature has been directed toward the effects of the pandemic on L2 learners' different affective factors. Locally, this study focuses on the perceived impacts on Saudi EFL learners' motivation, anxiety, and …

Exploring The Perspectives Of Black Male Students At An Hbcu In Rural Mississippi And The Role Non-Cognitive Factors Within A First-Year Experience Program Play In Their Continued Enrollment, Billy J. Benson, Jr.

Electronic Theses and Dissertations

Retention and graduation rates are declining nationwide but are exceptionally low for Black men. Extant research substantiates that various influences contribute to a student’s ability to persist to graduation. Apart from the positive impact of HBCUs on educational outcomes for Black students, empirical research highlights that enrollment, campus engagement, retention, success, and graduation are problematic (Palmer et al., 2013). Many factors—academic and non-cognitive—affect a student’s ability to persist to graduation (Bosco, 2021).

This problem of practice (PoP) explores the perspectives of Black male students at an HBCU in rural Mississippi and the role non-cognitive factors within a first-year experience program …

Error And F -Divergence Analysis Of Generative Adversarial Network, Mahmud Hasan

Electronic Theses and Dissertations

In this dissertation, the focus is to investigate the convergence rates of error and estimation bounds of various f-divergence metrics in the context of generative adversarial networks (GANs). The error convergence rate is developed and explained by a class of functions with the discriminator and generator neural networks. The new class of functions is uniformly bounded, VC type, with bounded envelope function and Vapnik–Chervonenkis (VC) dimension dimension which makes it possible to apply Talagrand inequality. A tight convergence rate is derived for the error of GAN after applying the Talagrand inequality and Borel-Cantelli lemma. The error bound is generalized for …

An Applied Research Study On Improving Special Education Identification And Support For Grades 3-6: Assessing The Impact Of The Tier 3 Process, Nickie Malone

Electronic Theses and Dissertations

Addressing the urgent need for effective literacy instruction, especially for students with diverse learning needs, is paramount in today's educational landscape. This dissertation investigates the implementation and impact of the Multi-Tiered System of Supports (MTSS) framework, particularly the Tier 3 process, at AUES in grades 3-6. The study aims to shed light on the systemic gaps in special education identification and support, evolving pedagogical approaches, and the role of educators and institutions in shaping literacy outcomes.

Grounded in the principles of equity and inclusion, the MTSS framework emerges as a promising avenue for providing personalized support and instruction tailored to …

Listening To Black Holes Ring: High-Precision Ringdown Modelling, Lorena Magaña Zertuche

Electronic Theses and Dissertations

After decades of promise, gravitational waves from a binary black hole system were detected on September 14, 2015 by the Laser Interferometer Gravitational-Wave Observatory (LIGO). Since then, close to 100 new gravitational-wave detections, including those from neutron star and neutron star-black hole binaries, have been made jointly by the LIGO, Virgo, and KAGRA (LVK) collaboration. LIGO's fourth observing run (O4) has begun, and signals on the order of one per week are expected. This rate will only increase as third-generation ground-based detectors will be getting hundreds of thousands of gravitational-wave signals when they go online in the next decade. Moreover, …

Optimizing The Performance Of Polyimide And Polyetherimide Nanocomposites Against Atomic Oxygen Attack And/Or Hypervelocity Impact, Grace Rushing

Electronic Theses and Dissertations

As humanity continues to push the boundaries of exploration beyond Earth, the need to develop materials that can withstand this harsh environment increases. Two types of materials were exposed to the low earth orbit (LEO) space environment on the International Space Station (ISS) for one year: (1) polyimide composites enhanced with polyhedral oligomeric silsequioxane (POSS) and (2) polyetherimide-graphene nanoplatelet (PEI-GNP) composites. Both exposed and non-exposed samples were characterized and compared, and the mass loss was calculated. The effects of the LEO environment, particularly atomic oxygen (AO), were investigated. X-Ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FTIR), and digital microscopy …

Exploring A Link Between Expected Family Contribution And Continued Enrollment At Holmes Community College, Matthew Ryan Surrell

Electronic Theses and Dissertations

The challenges facing higher education institutions across this country continue to increase, becoming more and more complex with each passing semester. Higher education administrators and those who aspire to be such must constantly stay abreast of all potential adverse issues, but especially those that affect the educational success of our students. The importance of student success is invaluable to students and society, alike, as their educational achievements enable the growth of both social efficiency and social mobility. Therefore, higher education institutions and their administrations must constantly assess and attempt to mitigate the many challenges and barriers to these important accomplishments. …

Heterologous Expression, Isolation, And Metabolomic Profiling Of Myxobacteria To Explore Their Potential In Natural Product Biosynthesis, Nawal Mohamed Hamed Elsayed Shehata

Electronic Theses and Dissertations

Myxobacteria are distinguished by their ability to produce a spectrum of natural products,positioning them as an active resource for therapeutic discovery. These products include metabolites with significant antibacterial, antifungal, cytotoxic, antiviral, and immunosuppressive properties. Current synthetic biology tools for the exploration of myxobacteria are not as advanced as those for the well-studied Streptomyces. This thesis presents an evolution of synthetic biology techniques specifically designed for the exploitation of myxobacteria in the realm of natural product discovery. Chapter One investigates the potential of myxobacteria to act as heterologous hosts due to their large genomes and their capacity for diverse biosynthetic processes. …