Digital Commons Network^™

Ppo2 Mutations In Amaranthus Palmeri: Implications On Cross-Resistance, Pamela Carvalho-Moore, Gulab Rangani, James Heiser, Douglas Findley, Steven J. Bowe, Nilda Roma-Burgos

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

In Arkansas, resistance to protoporphyrinogen IX oxidase (PPO)-inhibiting herbicides in Amaranthus palmeri S. Wats. is mainly due to target site mutations. Although A. palmeri PPO-mutations are well investigated, the cross-resistance that each ppo mutant endows to weed populations is not yet well understood. We aimed to evaluate the response of PPO-resistant A. palmeri accessions, harboring the ppo2 mutations ΔG210 and G399A, to multiple PPO-inhibiting herbicides. Six resistant and one susceptible field accessions were subjected to a dose–response assay with fomesafen, and selected survivors from different fomesafen doses were genotyped to characterize the mutation profile. The level of resistance …

Genome-Wide Association Study And Genomic Selection For Yield And Related Traits In Soybean, Waltram Second Ravelombola, Jun Qin, Ainong Shi, Qijian Song, Jin Yuan, Fengmin Wang, Pengyin Chen, Long Yan, Yan Feng, Tiantian Zhao, Yaning Meng, Kexin Guan, Chunyan Yang, Mengchen Zhang

Horticulture Faculty Publications and Presentations

Soybean [Glycine max (L.) Merr.] is a crop of great interest worldwide. Exploring molecular approaches to increase yield genetic gain has been one of the main challenges for soybean breeders and geneticists. Agronomic traits such as maturity, plant height, and seed weight have been found to contribute to yield. In this study, a total of 250 soybean accessions were genotyped with 10,259 high-quality SNPs postulated from genotyping by sequencing (GBS) and evaluated for grain yield, maturity, plant height, and seed weight over three years. A genome-wide association study (GWAS) was performed using a Bayesian Information and …

Faculty Research Profile: Bin Dong, Lutishoor Salisbury, Yang Tian, Jeremy Smith

University Libraries Faculty Publications and Presentations

This poster was compiled to commemorate the hiring of Dr. Bin Dong as Assistant Professor to the Department of the Chemistry and Biochemistry at the University of Arkansas from August 2021. It provides a summary of his research achievements and scholarly impact.

Clinehelpr: An R Package For Genomic Cline Outlier Detection And Visualization, Bradley T. Martin, Tyler K. Chafin, Marlis R. Douglas, Michael E. Douglas

Biological Sciences Faculty Publications and Presentations

Background

Patterns of multi-locus differentiation (i.e., genomic clines) often extend broadly across hybrid zones and their quantification can help diagnose how species boundaries are shaped by adaptive processes, both intrinsic and extrinsic. In this sense, the transitioning of loci across admixed individuals can be contrasted as a function of the genome-wide trend, in turn allowing an expansion of clinal theory across a much wider array of biodiversity. However, computational tools that serve to interpret and consequently visualize ‘genomic clines’ are limited, and users must often write custom, relatively complex code to do so.

Results

Here, we introduce the ClineHelpR R-package …

Uk Consumers’ Preferences For Ethical Attributes Of Floating Rice: Implications For Environmentally Friendly Agriculture In Vietnam, Vo Hong Tu, Steven W. Kopp, Nguyen Thuy Trang, Andreas Kontoleon, Mitsuyasu Yabe

Marketing Faculty Publications and Presentations

Vietnam plays an important role in bearing global food security. However, Vietnamese rice farmers face several challenges, including pressures to develop sustainable livelihoods while reducing the environmental impacts of their production activities. Various Vietnamese agricultural restructuring policies were promulgated to promote the adoption of environmentally friendly practices to generate high value added for rice farmers, but the farmers are reluctant to adopt them because of perceived lack of demand. Decreasing consumption of rice in Asia and increasing demands in Europe shaped Vietnamese rice exporting policies. New trade agreements, such as the UK–Vietnam Free Trade Agreement, offer new target markets for …

Simple Lamp Pcr Design For Low Resource Setting And Minimal Environmental Footprint, Robert Beitle Jr., Christa N. Hestekin, Ahmed K. Ali Elmasheiti, Kimberly Cribbs, Michael Rienisch, Bryce Cameron Jones, Allysa Swearingen, Brandon Hart, Kevin Clark, Vicki Thompson

Patents Granted

The present invention provides a device and method for testing a material for the presence of DNA. The system includes a centrifuge, a microchip performing cell lysis and an enclosure that contains an isothermal ballast material and chromogenic agent that melts at a specific temperature and displays a color change, respectively.

Systematics Of Eastern North American Podothrombium (Parasitengona: Podothrombiidae), Kelsey Lynn Cline

Graduate Theses and Dissertations

Velvet mites of the genus Podothrombium Berlese, 1910 are found worldwide with only two described species known from North America, both occurring on the west coast. The present study describes five new species occurring in the east, from both larval and post-larval stages. Species hypotheses are supported with morphology and analysis of mitochondrial (barcoding region of COI) and nuclear genes (D2-3 expansion regions of 28S rDNA). Specimens are incorporated from the Barcode of Life Data Systems (BOLD), allowing our dataset to span most of North America. Therefore, we were able to raise the number of Podothrombium in North America from …

Age, Ty Barnes

Graduate Theses and Dissertations

Age is a body of work that uses open ended, multi-directional narrative, economical craft, body positioning, and disorder to create situations for curiosity to take hold and rekindle a sense of naivety. Intentionally pedestrian material choice and playful, curious methodology work in tandem with the visual language of play to create a world building opportunity for the participating viewer. The objects are anchors or starting points with spaces in between for flexible narratives and imagined and reimagined worlds with no prescribed beginning or end point.

The exhibition and written thesis represent a conglomeration of connected-by-association ideas, a Rube Goldberg machine …

Nocturnal Pollination In Fruit Agriculture, Stephen Robertson

Graduate Theses and Dissertations

Insect pollination in agriculture provides as much as 35% of the global food supply and contributes hundreds of billions of dollars to the global economy each year. In the past 30 years, reports of declining populations of managed and wild bees, notably the western honey bee (Apis mellifera) and a wide array of bumble bees (Bombus spp.), have raised concerns about the stability and outlook of agriculture. At the same time, agricultural dependence on insect pollinators is increasing as greater percentages of land being converted to pollinator-dependent crops, such as soy and oil palm, than pollinator-independent crops, such as grains …

Assimilation Of Seasonal Moisture Variability In North America And Asia For The Last Millennium, Chang Liu

Graduate Theses and Dissertations

The seasonal tree-ring chronologies that recorded discrete moisture signal for warm and cool season have been used to reconstruct the North America Seasonal Precipitation Atlas (NASPA) by the point-by-point regression method, and the results indicated that they can fairly reproduce the seasonal precipitation variability in the past. Compared with reconstructions using only paleoclimate proxy data, the paleoclimate data assimilation (PDA) considers both proxy data and climate model output, so the PDA reconstructions are consistent with both the climate signals reflected by the proxy data and the physical mechanisms represented by climate models. Based on the tree rings with discrete seasonal …

Rice From Paddy To Pantry To Plate: Mitigating Rice Blast Disease With Saponins Of Medicago, Improving Shelf Life With Crispr, And Exploring Global Cuisine Through Text Analysis, Kathryn Haydon

Graduate Theses and Dissertations

Rice is the staple food for more than half the world’s population, with nearly 500 million metric tons of rice consumed globally every year. Any risk of loss due to disease, waste, or spoilage is therefore noteworthy. This dissertation explores the passage of rice from paddy to pantry to plate, with special attention given to disease and storage life. The most important disease of rice is blast, caused by the ascomycete Magnaporthe oryzae, which can cause losses of ~30% every year. This study found that saponin-enriched root extracts of Medicago truncatula effectively kill fungal spores in vitro and reduce moderate …

Computational Frameworks For Multi-Robot Cooperative 3d Printing And Planning, Laxmi Prasad Poudel

Graduate Theses and Dissertations

This dissertation proposes a novel cooperative 3D printing (C3DP) approach for multi-robot additive manufacturing (AM) and presents scheduling and planning strategies that enable multi-robot cooperation in the manufacturing environment. C3DP is the first step towards achieving the overarching goal of swarm manufacturing (SM). SM is a paradigm for distributed manufacturing that envisions networks of micro-factories, each of which employs thousands of mobile robots that can manufacture different products on demand. SM breaks down the complicated supply chain used to deliver a product from a large production facility from one part of the world to another. Instead, it establishes a network …

Tribological Studies Of Thick Polytetrafluoroethylene Coatings Enhanced By Polydopamine And Nanoparticles, Sujan Kumar Ghosh

Graduate Theses and Dissertations

Polytetrafluoroethylene (PTFE) is a popular low friction solid lubricant with high chemical and thermal stability. Thick PTFE coatings have the potential for many tribological applications, such as replacing Tin-based Babbitt materials in journal bearings. However, the weak bonding strength to the substrate and the high wear rate of PTFE coatings are current limiting factors. The lack of understanding of their tribological properties and wear mechanisms in oil-lubricated conditions and how coating thickness affects the tribological performance further hindered the use of PTFE coatings. In this dissertation, polydopamine (PDA), a bio-inspired adhesive, is used as an underlayer for or as a …

Establishment Of Pollinator Habitat Within A Livestock Pasture Ecosystem, Roshani Sharma Acharya

Graduate Theses and Dissertations

Pollinators are important for fertilization, setting fruits, and seed development of more than 78% of the flowering plants that provide food for human beings and other species. Use of pollinators to maximize crop production is a proven agricultural practice; however, it has been less explored in livestock forage production systems. This study investigated pollinator abundance and diversity in pastures using different sampling methods and determined the impact of different pasture management practices on insect pollinators in a livestock pasture ecosystem. In Chapter 2, utility of four different colors of pan trap (blue, green, yellow, and purple) for sampling bees in …

Influence Of Extracellular Matrix Stiffness And Topography On Neuronal Cell Behavior And Neurite Outgrowth, Mohan Yasodharababu

Graduate Theses and Dissertations

The focus of regeneration therapy for traumatic brain injuries and Alzheimer's disease is on the promotion and growth of neuronal cells. In vitro research attempts to improve this by modifying the stiffness and topography of the extracellular matrix (ECM). However, the limitations of in vitro experiments make it difficult to control the individual factors influencing neuronal cell growth. A computational model can be used to decouple individual factors and study them individually to gain a better understanding of the mechanics between the neuronal cell and ECM, which will aid in the design of in vitro experimental studies.

This study develops …

Directed Genome Evolution To Identify Genes For Macrophage Survival By Staphylococcus Agnetis, Sonali Lakshika Anne Lenaduwe Lokuge

Graduate Theses and Dissertations

Bacterial Chondronecrosis with Osteomyelitis (BCO) is a debilitating infection that negatively impacts animal welfare and costs the broiler industry billions of dollars annually. We have previously isolated Staphylococcus agnetis 908 from BCO samples obtained from broilers at the University of Arkansas research farm. This isolate can induce BCO lameness at greater than 50% in broilers exposed to the pathogen in drinking water. We found that S. agnetis 908 is capable of surviving and escaping macrophages compared to a closely related cattle isolate,1379. Through Directed Genome Evolution (DGE) we identified that this difference is at least partially associated with an alanine …

Towards A Large-Scale Intelligent Mobile-Argumentation And Discovering Arguments, Controversial Topics And Topic-Oriented Focal Sets In Cyber-Argumentation, Najla Althuniyan

Graduate Theses and Dissertations

User-generated content (UGC) platforms host different forms of information, such as audio, video, pictures, and text. They have many online applications, such as social media, blogs, photo and video sharing, customer reviews, debate, and deliberation platforms. Usually, the content of these platforms is provided and consumed by users. Most of these platforms, mainly social media and blogs, are often used for online discussion. These platforms offer tools for users to share and express opinions. Commonly, people from different backgrounds and origins discuss opinions about various issues over the Internet. Furthermore, discussions among users contain substantial information from which knowledge about …

Investigation Of Factors Influencing Recombination Versus Disproportionation Of Complex Radicals Formed By C-N Homolysis Of Breslow Type Intermediates And Related Compounds, Taylor Burnett

Graduate Theses and Dissertations

Electron rich enamines are capable of C-N bond homolysis and subsequent recombination and/or disproportionation. It is unclear what causes these radicals to undergo recombination or disproportionation. Density Functional Theory (DFT) calculations do not provide a transition state for the recombination and disproportionation processes and therefore they cannot be used to predict the favorable reaction. Breslow intermediates formed by deprotonation of thiazolium salts and reaction with aromatic aldehydes are examples of electron rich enamines. These breslow intermediates can undergo C-N bond homolysis to form a radical pair the either recombine or disproportionate. Upon investigation of the factors influencing recombination and disproportionation, …

Consulting Place As Stakeholder: Accessing The Input Of Ecological Community, Hunter Adkisson

Landscape Architecture Undergraduate Honors Theses

This is a project about how landscape architects approach the landscape in their design process. Indigenous worldviews hold that the world is living and animate in its own right. When we consider stakeholder engagement in this light, the need arises to extend the definition of stakeholders to include the ecological communities of place – the flora, fauna, soils, and other non-human elements of place. To gather that input, I experimented with techniques to access a greater awareness of ecological community at two sites with different levels of urbanity and types of land management practices. This experimental approach was surprisingly successful …

Host-Parasite Interactions Within Food Webs, Adam Zvanut Hasik

Graduate Theses and Dissertations

Parasitism is one of the most common life history strategies employed in nature, yet the effects of parasites are often thought to be minimal, and the vast majority of studies fail to consider parasites and their effects on host organisms. This is likely a problem, as the magnitude of parasite-mediated effects on their hosts can be quite large. Additionally, the effects of parasites are known to extend beyond the host to affect other species interactions. I used a series of approaches to gain a more integral understanding of host-parasite interactions by studying (1) the effects of parasites on biotic interactions …

Medical Error Disclosure: A Content Analysis Of State Legislation, Teresa Kathleen Sparks

Graduate Theses and Dissertations

Medical error is a public health problem in the United States (U.S.), causing approximately 250,000 hospital deaths per year. Health care leaders and policy-makers have identified medical error disclosure as one of many viable evidence-based solutions to address the problem of medical error – leading to increased transparency in health care, improved patient outcomes, potential medical malpractice cost reduction, and decreased health care provider distress and turnover. Unfortunately, health care providers are often hesitant to practice disclosure and are not required to do so in most U.S. jurisdictions. A qualitative inquiry using content analysis was conducted to understand the language …

Negative Urgency's Influence On State-Level, Emotion-Based Changes In Alcohol-Related Cognitions, Noah Wolkowicz

Graduate Theses and Dissertations

This project expanded on the Acquired Preparedness Model of Risk (APMR) by examining how Negative Urgency (NU), the tendency to act rashly in negative emotional states, affects emotion-based changes in alcohol cognitions to produce risk for alcohol use. The APMR prioritizes the role of outcome expectancies as the means through which traits such as NU, convey alcohol use risk. However, this model treats these cognitions as static and often fails to assess their valence; further, alcohol-cognitions fluctuate in response to negative emotions and may become more salient during these states. Therefore, this study examined: 1) how NU impacts negative emotion-based, …

Of Biodiversity, Boundaries, And Distribution: The Myxomycetes Of The Philippines And Beyond, Sittie Aisha Bustamante Macabago

Graduate Theses and Dissertations

This dissertation contains a compilation of independently performed studies primarily focusing on the myxomycetes (plasmodial slime molds) from the Philippines and integrating local and worldwide data to demonstrate regional and global trends. The major themes include the following: (I) a review of the diverse group of spore-producing amoeboid protists, including the myxomycetes; (II-IV) diversity assessments in three different groups of islands in the Philippine archipelago; (V) mapping the myxomycetes found in the Philippines for databasing and analyzing the geocoded data; (VI) a study on regional boundaries, including the Philippines, using myxomycete species composition; and, (VII) creating a global species distribution …

An Automated Method To Enrich And Expand Consumer Health Vocabularies Using Glove Word Embeddings, Mohammed Ibrahim

Graduate Theses and Dissertations

Clear language makes communication easier between any two parties. However, a layman may have difficulty communicating with a professional due to not understanding the specialized terms common to the domain. In healthcare, it is rare to find a layman knowledgeable in medical jargon, which can lead to poor understanding of their condition and/or treatment. To bridge this gap, several professional vocabularies and ontologies have been created to map laymen medical terms to professional medical terms and vice versa. Many of the presented vocabularies are built manually or semi-automatically requiring large investments of time and human effort and consequently the slow …

Scheduling Allocation And Inventory Replenishment Problems Under Uncertainty: Applications In Managing Electric Vehicle And Drone Battery Swap Stations, Amin Asadi

Graduate Theses and Dissertations

In this dissertation, motivated by electric vehicle (EV) and drone application growth, we propose novel optimization problems and solution techniques for managing the operations at EV and drone battery swap stations. In Chapter 2, we introduce a novel class of stochastic scheduling allocation and inventory replenishment problems (SAIRP), which determines the recharging, discharging, and replacement decisions at a swap station over time to maximize the expected total profit. We use Markov Decision Process (MDP) to model SAIRPs facing uncertain demands, varying costs, and battery degradation. Considering battery degradation is crucial as it relaxes the assumption that charging/discharging batteries do not …

Evaluating The Efficiency Of Markov Chain Monte Carlo Algorithms, Thuy Scanlon

Graduate Theses and Dissertations

Markov chain Monte Carlo (MCMC) is a simulation technique that produces a Markov chain designed to converge to a stationary distribution. In Bayesian statistics, MCMC is used to obtain samples from a posterior distribution for inference. To ensure the accuracy of estimates using MCMC samples, the convergence to the stationary distribution of an MCMC algorithm has to be checked. As computation time is a resource, optimizing the efficiency of an MCMC algorithm in terms of effective sample size (ESS) per time unit is an important goal for statisticians. In this paper, we use simulation studies to demonstrate how the Gibbs …

Nanomaterial-Based Biosensors For Detection Of Salmonella Typhimurium And Avian Influenza Virus H5n1 In Poultry, Xinge Xi

Graduate Theses and Dissertations

This research focused on developing biosensing method and biosensing device for rapid detection of pathogens in poultry: Salmonella Typhimurium and avian influenza virus H5N1. The first part of the dissertation reports an original research on the development of a portable biosensing device for Salmonella detection. The device was designed and constructed based on a previously developed optical biosensing method, using immuno-magnetic nanoparticles to specifically capture target bacteria, and immuno-quantum dot beads to label the target bacteria for fluorescence detection. All the actions of sample mixing, magnetic separation, and fluorescence detection were controlled automatically in a disposable microfluidic chip in the …

Vulnerability To And Protection Against Covid-19 Fear, Threat, And Worry, Marsha Kim Huh

Graduate Theses and Dissertations

Drawing from a sample of 10,368 adults living in the U.S., the current study examines the role of social and psychological resources in lowering COVID-related fear, threat, and worry, controlling for a number of social vulnerabilities (e.g. gender, race/ethnicity, and presence of children). The impact of social location, particularly in regards to race, and how one accesses and/or utilizes social and psychological resources is also examined through disaggregated regression models. Results demonstrate that some social and psychological resources impact COVID-specific distress (fear/threat/worry), but depending on the resource, relationships vary in direction and significance. The strength of social ties and mastery …

Nutrient Sources, Loads And Trends Vary Spatially And Temporally Within The Poteau River Watershed And Lake Wister, Oklahoma, Abbie Lasater

Graduate Theses and Dissertations

Excess inputs of nutrients and sediments jeopardize drinking water sources, aquatic life habitats, and aesthetic quality of freshwater resources for recreation. The purpose of this dissertation was to analyze long-term water quality trends and loads in the Upper Poteau River Watershed (UPRW) and the Lake Wister Watershed (LWW), and analyze internal phosphorus (P) loads in Lake Wister, Oklahoma. Additionally, this dissertation sought to review the literature for methods of prioritizing subwatersheds for watershed management using watershed models, implement a cost efficient method to remotely monitor streamflow and estimate constituent loads in small-scale watersheds, and finally, to validate the Soil Water …

Recurrent Selection With Sub-Lethal Doses Of Mesotrione Reduces Sensitivity In Amaranthus Palmeri, Jason K. Norsworthy, Vijay K. Varanasi, Muthukumar Bagavathiannan, Chad Brabham

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Amaranthus palmeri, ranked as the most prolific and troublesome weed in North America, has evolved resistance to several herbicide sites of action. Repeated use of any one herbicide, especially at lower than recommended doses, can lead to evolution of weed resistance, and, therefore, a better understanding of the process of resistance evolution is essential for the management of A. palmeri and other difficult-to-control weed species. Amaranthus palmeri rapidly developed resistance to 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors such as mesotrione. The objective of this study was to test the potential for low-dose applications of mesotrione to select for reduced susceptibility over …