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Full-Text Articles in Life Sciences

Biomechanical Evaluation Of Functional Ability And Postural Stability In Patients With Diabetic Peripheral Neuropathy Disorder, Safi Ullah Dec 2021

Biomechanical Evaluation Of Functional Ability And Postural Stability In Patients With Diabetic Peripheral Neuropathy Disorder, Safi Ullah

Theses and Dissertations

BACKGROUND: Diabetic peripheral neuropathy (DPN) is a very common disease most prevalent in people with type-II diabetes. DPN is caused by high blood glucose levels that instigates nerve damage which results in sensation loss mainly in the lower extremities. RESEARCH OBJECTIVE: The objective of this study is to explore into the motor disability resulting from DPN disorder by investigating into the muscle activation patterns, force output in lower extremity muscles, the onset of muscle fatigue and most importantly evaluating the postural stability in DPN patients and comparing the results to healthy control subjects. We hypothesize that the DPN patients suffer …


The Utilization Of Enzymes And Enzyme Products For Antimicrobial Effects, Brandon Edward Burdette Dec 2021

The Utilization Of Enzymes And Enzyme Products For Antimicrobial Effects, Brandon Edward Burdette

Theses and Dissertations

Bacterial resistance is outpacing the discovery of novel antimicrobials. Therefore, it is essential to look at antimicrobials using novel methods. MTAN is a crucial enzyme for some bacteria such as Helicobacter pylori. Transition state analog inhibitor design and fragment-based drug design are drug design approaches typically used independently, but combining these techniques yields inhibitors that bind tightly and are effective in pM concentrations. We demonstrate the efficacy of the combined techniques by investigating the inhibition of HpMTAN, which is an essential enzyme. Enzyme byproducts can also be effective for causing bacterial cell death, hydrolyzing GsdmD by caspases-1/4/5/11 results in an …


A Comparison Of The Effects Of Heat Therapy And Exercise Training On Vascular Function During Passive And Active Exercise, Taysom Erica Wallace Dec 2021

A Comparison Of The Effects Of Heat Therapy And Exercise Training On Vascular Function During Passive And Active Exercise, Taysom Erica Wallace

Theses and Dissertations

Recent evidence suggests that heat, a major byproduct of exercise, may be the mediator for many vascular adaptations that come from exercise. Thus, heat therapy that increases muscle temperature in a comparable way to exercise may be an advantageous alternative for enhancing cardiovascular health in individuals where treatment with exercise is either not possible or undesired. PURPOSE: Compare the effects of exercise and heat training on resistance artery function at rest and during exercise. METHODS: Thirty-five (18 female) healthy, untrained subjects completed a 6-week training program utilizing either high intensity knee extension (KE) exercise (40 min), localized heat therapy (pulsed …


Predicting Drug-Induced Liver Injury With Artificial Intelligence, Ting Li Dec 2021

Predicting Drug-Induced Liver Injury With Artificial Intelligence, Ting Li

Theses and Dissertations

Drug-induced liver injury (DILI) is an undesirable side effect to the liver caused by the common use of drugs, which is of great concern to the patients, physicians, the pharmaceutical industry, and government regulators. The current animal testing models do not present reliable results on the human DILI risk prediction during the preclinical phase. Therefore, there is an urgent need to find alternative methods to improve the human DILI risk prediction during the early stage of development. Utilizing the accumulated high-throughput transcriptomics profiles from L1000, we constructed an 8-layer deep neural network for human DILI prediction based on the largest …


Behavioral Patterns Of Goldfish (Carassius Auratus) Exploring A “Fish Tower”, Sasha Prasad-Shreckengast Dec 2021

Behavioral Patterns Of Goldfish (Carassius Auratus) Exploring A “Fish Tower”, Sasha Prasad-Shreckengast

Theses and Dissertations

Fish are held in captivity at some of the highest numbers of any taxa, but their curiosity is rarely studied. With this study, we set the groundwork to investigate the presence and nature of curiosity in goldfish (Carassius auratus) via novel free-choice exploration opportunities by creating a “fish tower."


Functional Characterization Of Arabidopsis Synaptotagmin-4 Protein Through Reverse Genetics Strategy, Zahid Jawed Dec 2021

Functional Characterization Of Arabidopsis Synaptotagmin-4 Protein Through Reverse Genetics Strategy, Zahid Jawed

Theses and Dissertations

Calcium ion plays a significant role in plant signal transduction pathways, including regulation of stress-induced gene expression. Sensor proteins such as proteins with calcium-binding C2 domains can perceive changes in cellular calcium level. Functional analysis of such sensor proteins will give us a better understanding of plant stress signaling. Synaptotagmins are a group of proteins containing C2 domains that are capable of binding calcium ions and regulate gene expression in response to external abiotic stress stimuli. Here, we used a reverse genetic approach to analyze the function of synaptotagmin – 4, which is one of the five identified synaptotagmin proteins …


Identifying Micrornas Panel Associated With Hepatocellular Carcinoma In Serum Of Chronic Hepatitis C Patients, Areeg Dabbish Dec 2021

Identifying Micrornas Panel Associated With Hepatocellular Carcinoma In Serum Of Chronic Hepatitis C Patients, Areeg Dabbish

Theses and Dissertations

Introduction: early detection of hepatocellular carcinoma (HCC) will reduce morbidity and mortality rates of this poorly diagnosed widely-spread disease. Dysregulation in microRNA (miRNAs) expression is associated with HCC progression. Objective: Is to identify a panel of differentially expressed miRNAs (DE-miRNAs) to enhance HCC early prediction in hepatitis C virus (HCV) infected patients. Methodology: Candidate miRNAs were selected using bioinformatic analysis of microarray and RNA-sequencing datasets, resulting in nine DE- miRNAs (miR-142, miR-150, miR-183, miR-199a, miR-215, miR-217, miR-224, miR-424 and miR-3607). Their expressions were validated in the serum of 44 healthy individuals, 62 non-cirrhotic HCV patients, 67 cirrhotic-HCV and 72 HCV-associated …


Utilizing Isothermal Titration Calorimetry For Measuring Beta-Galactosidase Activity In Liquid Dairy Products, Eliza Anne Brock Dec 2021

Utilizing Isothermal Titration Calorimetry For Measuring Beta-Galactosidase Activity In Liquid Dairy Products, Eliza Anne Brock

Theses and Dissertations

This research explores Isothermal Titration Calorimetry as a method for measuring beta-galactosidase activity directly and continuously in milk, sweet whey, sweet whey permeate, acid whey, and acid whey permeate. Beta-galactosidase in various concentrations was injected into each of the liquid dairy products spiked with lactose to verify if the heat rate from the enzymatic reaction could be observed. In addition, a consistent concentration of beta-galactosidase was injected into various concentrations of lactose in the products, to observe the heat rates from the enzymatic reaction. There was exothermic activity that never returned to baseline demonstrated in milk, sweet whey, and sweet …


Pushing It To The Limit: Determining Asian Elephant (Elephas Maximus) Olfactory Sensitivity And Discrimination Through A Behavioral Choice Task, Matthew S. Rudolph Dec 2021

Pushing It To The Limit: Determining Asian Elephant (Elephas Maximus) Olfactory Sensitivity And Discrimination Through A Behavioral Choice Task, Matthew S. Rudolph

Theses and Dissertations

Elephants have shown remarkable olfactory capabilities. Their sense of smell impacts their foraging choices, behavior, and ultimately, survival. Being able to detect a target odor can allow elephants to locate specific resources, identify threats, and find receptive conspecifics. Previous studies have shown that elephants can consistently detect target odors, but have not identified the limits of this detection. Thus, to investigate the extent of elephants’ odor detection capabilities, we tested Asian elephants in a two-step odor discrimination task. First, we investigated whether elephants could detect odors at varying levels of dilution after a training procedure, and then whether they could …


Restricted Microbial Presence, Activity, And Community Structuring Within Dry Valley Soils Of Antarctica, Scott Fillerup George Dec 2021

Restricted Microbial Presence, Activity, And Community Structuring Within Dry Valley Soils Of Antarctica, Scott Fillerup George

Theses and Dissertations

The McMurdo Dry Valley region is the largest ice-free area of Antarctica. Harsh abiotic conditions of the polar desert ecosystem, including extreme cold, aridity, and limited nutrient availability select for unique taxa. The comparatively simple terrestrial ecosystem is well-suited for investigating edaphic influences on microbial presence, activity, and community structuring. The Dry Valleys are viewed as a useful analog for Mars astrobiology investigations. However, most biotic investigations have been focused on lower elevations, where an understanding of edaphic effects on microbial communities within its generally more favorable conditions has emerged. Transiently wetted Dry Valley water tracks may be analogous to …


Mixture Design Response Surface Methodology Analysis Of Seven Natural Bioactive Compounds To Treat Prostate Cancer, Ian Geddes Berlin Dec 2021

Mixture Design Response Surface Methodology Analysis Of Seven Natural Bioactive Compounds To Treat Prostate Cancer, Ian Geddes Berlin

Theses and Dissertations

Natural bioactive compounds have drawn the interest of many researchers worldwide in their effort to find novel treatments, including prostate cancer (PC) treatment which is estimated to be 13.1% of all new cancer cases in the U.S. in 2021. Many of these bioactive compounds have been identified from treatments in traditional Chinese medicine (TCM), that often have multiple bioactive compounds present. However, in vitro studies frequently focus on the compounds in isolation, or in simple combinations of two compounds. We used mixture design response surface methodology (MDRSM) to assess changes in PC cell viability after 48 hours of treatment to …


Characterization Of Bacteriophage Targeting Bacillus Licheniformis In Milk Processes And Thermal Stability Of Bacteriophage During Htst Pasteurization, Jeremy Robert Arbon Dec 2021

Characterization Of Bacteriophage Targeting Bacillus Licheniformis In Milk Processes And Thermal Stability Of Bacteriophage During Htst Pasteurization, Jeremy Robert Arbon

Theses and Dissertations

An array of Bacillus licheniformis strains were isolated from a commercial powdered milk process. Bacteriophages exhibiting activity against B. licheniformis were isolated from cattle manure and effluent samples destined for a lagoon at a dairy farm. After sequencing, 8 of the 10 phages were found to be novel and genetically differentiated. Transmission electron scanning microscopy (TSEM) was performed. All bacteriophages were of the family Herelleviridae with contractile tail sheaths ranging from 80µm to 150µm and, surprisingly, survived a common fluid milk processing treatment used to inactivate vegetative cells. The survival of the phage after high temperature short time pasteurization of …


Active Targeting Of Estrogen Receptor (Er)-Positive Breast Cancer Cells Using Nanotechnology, Molly White Dec 2021

Active Targeting Of Estrogen Receptor (Er)-Positive Breast Cancer Cells Using Nanotechnology, Molly White

Theses and Dissertations

The American Cancer Society has predicted an estimated 281,550 new invasive breast cancer cases for 2021. Chemotherapy is one of the main options available to treat this disease, but it can result in drug resistance and harmful side effects, as traditional methods do not directly target the cancer cells. To address this issue, nano formulations have been widely researched for targeted delivery of anticancer drugs. The primary objective of this project was to develop a novel nanodrug, rapamycin-loaded gold nanorods functionalized with polyethylene glycol and epithelial cell adhesion molecule (EpCAM), to selectively target breast cancer cells. The work involved characterizing …


Phylogeny And Visual System Evolution In Sap Beetles (Coleoptera: Cucujoidea: Nitidulidae), Gareth S. Powell Dec 2021

Phylogeny And Visual System Evolution In Sap Beetles (Coleoptera: Cucujoidea: Nitidulidae), Gareth S. Powell

Theses and Dissertations

Coleoptera is currently the most diverse lineage of life on Earth with more than 400,000 described species. The group also contains unbelievable ecological and morphological variation that has been evolving since the early Carboniferous (>350 MYA). The group provides the perfect playground to test evolutionary hypotheses with large-scale phylogenies. First, a newly developed bioinformatics tool is presented that allows for the critical assessment of the stability of phylogenetic nodes with even minor changes in taxon sampling (i.e. a single taxon jackknifed). The tool, TANOS, is capable of performing tests on large genomics-scale datasets. The case study included is a …


Effects Of The Inclusion Of Rice Hull Derived Bio-Oil On Wood Pellet Production, Tyler E. Lowe Dec 2021

Effects Of The Inclusion Of Rice Hull Derived Bio-Oil On Wood Pellet Production, Tyler E. Lowe

Theses and Dissertations

Wood pellet production has become an advancing industry for the sake of reducing greenhouse emissions into the atmosphere especially, in European Union countries. Researchers and industry executives seek new methods and materials to improve the pelletization process. Rice hulls or husks has the potential to aid in wood pelletization as they possess high calorific values. This study focuses on using rice hull derived bio-oil from pyrolysis, which will also decrease ash content, as an additive to aid in the wood pelletization process. Using two groups of rice hull derived bio-oil as an additive in wood pelletization: Group 1 uses heavy …


Efficiency Of Weights Matrix Specification In The Spatial Error Model, Cannon Kent Dec 2021

Efficiency Of Weights Matrix Specification In The Spatial Error Model, Cannon Kent

Theses and Dissertations

This study investigates and quantifies the effect of different specifications of the spatial weights matrix (��) on estimates and inferences in the context of a regression model using the lattice perspective with polygon-type data. The study also investigates an alternative to the specification of �� by estimating a spatial variance-covariance matrix based on known features of the spatial data. Previous literature has addressed the a priori construction of �� and selection criteria but assumes point-type data. This study’s primary contribution is the setup of a true and known benchmark that allows the comparison of the different specifications of ��. This …


Molecular, Somatic, And Performance Characteristics Of Broilers Exhibiting Woody Breast Myopathy, And The Effects Of Dietary And Challenge Intervention Strategies, Linan Jia Dec 2021

Molecular, Somatic, And Performance Characteristics Of Broilers Exhibiting Woody Breast Myopathy, And The Effects Of Dietary And Challenge Intervention Strategies, Linan Jia

Theses and Dissertations

Woody breast (WB) is a meat quality problem that has caused significant economic losses for the poultry industry. Ross × Ross 708 chicks were randomly assigned to a 3 (diet) × 2 (cocci challenge) × 2 (sex) factorial arrangement of treatments. The three diets included the control diet (corn-soybean meal basal diet), antibiotic diet (basal diet + 6.075 mg bacitracin /kg feed), and probiotic diet (basal diet + 2.2 × 108 CFU Bacillus subtilis PB6 /kg feed). Birds in the cocci challenge treatment group received 20 × the live cocci vaccine as an inoculum on d 14. Growth performance and …


A Review Of Calcineurin Biophysics With Implications For Cardiac Physiology, Ryan B. Williams Dec 2021

A Review Of Calcineurin Biophysics With Implications For Cardiac Physiology, Ryan B. Williams

Theses and Dissertations

Calmodulin is a prevalent calcium sensing protein found in all cells. Three genes exist for calmodulin and all three of these genes encode for the exact same protein sequence. Recently mutations in the amino acid sequence of calmodulin have been identified in living human patients. Thus far, patients harboring these mutations in the calmodulin sequence have only displayed an altered cardiac related phenotype. Calcineurin is involved in many key physiological processes and its activity is regulated by calcium and calmodulin. In order to assess whether or not calcineurin contributes to calmodulinopathy (a pathological state arising from dysfunctional calmodulin), a comprehensive …


Assessing The Potential For Lightning-Induced Damage In Commercial Broiler Houses In Mississippi And Alabama, Matthew R. Rowland Dec 2021

Assessing The Potential For Lightning-Induced Damage In Commercial Broiler Houses In Mississippi And Alabama, Matthew R. Rowland

Theses and Dissertations

Modern broiler houses are expensive to build, maintain, and insure. Protecting them from extreme weather events is a major concern to producers, integrators, and insurance companies. Lightning strikes can cause catastrophic fires and electrical damage and can lead to costly bird losses. A greater understanding of the impact of lightning on the commercial broiler industries of MS and AL is needed. The objectives of this research were collection of baseline resistance data for broiler houses and equipment in both states, and mapping lightning strike densities across MS and AL, evaluating annual, monthly, seasonal, and diurnal patterns. 63.5% of surveyed broiler …


Soybean (Glycine Max) Response To Multiple, Sublethal Exposures Of 2,4-D And Dicamba From Vegetative Through Reproductive Growth, Graham Robert Oakley Dec 2021

Soybean (Glycine Max) Response To Multiple, Sublethal Exposures Of 2,4-D And Dicamba From Vegetative Through Reproductive Growth, Graham Robert Oakley

Theses and Dissertations

This study was conducted to determine whether soybean productivity is affected by multiple, sublethal herbicide exposures. The effects of dicamba and 2,4-D on soybean (Glycine max) productivity was investigated at 17 site-years. Relative to a single exposure of dicamba at R1, an additional exposure at either V3 or R3 reduced yield up to 23%. Three or more applications did not further decrease yields relative to an R1&R3 exposure. For 2,4-D, a single application to V3, R1, R3, or R5 soybean did not affect grain yield. However, two exposures of 2,4-D occurring from V3 through R3 reduced yield 5 to 7%. …


Examining The Need For Parental Satisfaction With The Msu Extension Equine Assisted Therapy Program, Ashlyn Ann Kiker Dec 2021

Examining The Need For Parental Satisfaction With The Msu Extension Equine Assisted Therapy Program, Ashlyn Ann Kiker

Theses and Dissertations

Animal assisted interventions are becoming more prevalent in our society. Animal interventions have become a popular therapy technique that exist to aid a variety of disabilities. Equine therapeutic riding has become one of the most popular forms of animal assisted therapy for both children and adults. While research shows the importance and benefits of animal assisted therapy for children, there is a lack of research concerning parental satisfaction within therapeutic riding programs.

This study tested a newly developed instrument for measuring parental satisfaction for therapeutic riding programs. The Parent/Caregiver Evaluation Tool (Kerr, 2021) was administered to parents/caregivers whose children participated …


The Art Of Amphibian Conservation: Linking In-Situ And Ex-Situ Populations Of Endangered Species Through Genome Banking, Isabella Joann Burger Dec 2021

The Art Of Amphibian Conservation: Linking In-Situ And Ex-Situ Populations Of Endangered Species Through Genome Banking, Isabella Joann Burger

Theses and Dissertations

Limited breeding success in captive breeding programs has necessitated the development of assisted reproductive technologies (ART) to preserve and increase genetic variation and population numbers of both captive and wild amphibian groups. ART has been shown to be successful in numerous anuran species, and current studies focus on the application of ART in ex-situ populations. The focus of this project is to show that linking in-situ and ex-situ amphibian populations through sperm cryopreservation, genome banking, and in-vitro fertilization is possible, with the goal of increasing gene diversity throughout groups in order to produce self-sustaining, wild populations in the future. Specific …


Modulation Of Effector Gene Expression In The Blood-Feeding Arthropods Cimex Lectularius Linnaeus, (Hemiptera: Cimicidae) And Aedes Albopictus Skuse, (Diptera: Culicidae), Travis C. Van Warmerdam Dec 2021

Modulation Of Effector Gene Expression In The Blood-Feeding Arthropods Cimex Lectularius Linnaeus, (Hemiptera: Cimicidae) And Aedes Albopictus Skuse, (Diptera: Culicidae), Travis C. Van Warmerdam

Theses and Dissertations

Hematophagy, or blood-feeding behavior, has independently evolved multiple times in the class Insecta and results in the transmission of vector-borne parasites, bacteria and viruses causing 17% of all infectious diseases and over 700,000 human deaths annually. One of the major challenges in studying the discrete mechanisms involved in host-response to hematophagy or the host seeking behavior of hematophagous insects, is the vast amount of signaling processes and genes that are inextricably tied to these interactions. These experiments used the clustered regularly interspersed short palindromic repeat (CRISPR)/CRISPR-associated (Cas) and dsRNA knock-down technologies to examine mechanisms of immunological reactivity and host-seeking behavior. …


Seasonal Management Strategies For Tarnished Plant Bug, Lygus Lineolaris (Palisot De Beauvois), In Midsouth Cotton Production Systems, Ryan Taylor Mann Dec 2021

Seasonal Management Strategies For Tarnished Plant Bug, Lygus Lineolaris (Palisot De Beauvois), In Midsouth Cotton Production Systems, Ryan Taylor Mann

Theses and Dissertations

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is considered the most economically important pest of midsouth cotton. This study was designed to understand the impact of tarnished plant bug populations in the later weeks of flowering cotton and residual effects of novaluron with subsequent applications. Experiments evaluated dynamic threshold approaches in the later flowering period of midsouth cotton, the impacts of novaluron plus subsequent applications at the 3rd week of square, as well as residual properties in a laboratory experiment. Results suggest that a dynamic late season approach can reduce the amount of insecticide applications targeting tarnished …


Field Durability Test Of Clt Wall Envelope Using Physical Barriers Against Termites And Structural Performance Of Nailed Hold-Down Brackets Connected To Fungus-Exposed Clt Walls, Kamal Neupane Dec 2021

Field Durability Test Of Clt Wall Envelope Using Physical Barriers Against Termites And Structural Performance Of Nailed Hold-Down Brackets Connected To Fungus-Exposed Clt Walls, Kamal Neupane

Theses and Dissertations

The effectiveness of using commercial polyethylene flashing and stainless-steel mesh in CLT wall systems as the termite barriers were evaluated in a short-term field test. American Wood Protection Association (AWPA) E21's visual ratings ranged from 10 to 9 in the specimens showing little damage when no physical barriers were used. Termites were able to crawl beyond the physical barriers in few specimens showing the necessity of further research on height and installation method of physical barriers. On the second part, the effect of decay caused due to Postia placenta, a brown-rot fungus, on the structural performance of hold-down brackets connected …


Evaluation Of The Variable Rate Capabilities Of A Sprayer Equipped With Pulse Width Modulation Nozzle Control And Direct Chemical Injection Systems, William Walker Dec 2021

Evaluation Of The Variable Rate Capabilities Of A Sprayer Equipped With Pulse Width Modulation Nozzle Control And Direct Chemical Injection Systems, William Walker

Theses and Dissertations

Variable-rate technologies coupled with broadcast spray systems serve to reduce chemical inputs, misapplication of chemicals, and environmental pollution, thus improving profitability and sustainability. Sprayer variable rate control involves using pulse width modulation (PWM) solenoids and/or direct chemical injection to adjust the application rate. The objectives of this research were to: outfit a conventional broadcast sprayer with PWM and direct inject technologies; evaluate the accuracy of the PWM system to control application rate for strait line and turn segments; and characterize the direct injection system’s transport delay time. For the PWM evaluation, the mean flow rate and coefficient of variation of …


Positive Correlation Between A3 Subunit Of Glycinin And Firmness Of Tofu Made From Soybeans Grown In Three Locations Over Two Years, Ruiqi Chen Dec 2021

Positive Correlation Between A3 Subunit Of Glycinin And Firmness Of Tofu Made From Soybeans Grown In Three Locations Over Two Years, Ruiqi Chen

Theses and Dissertations

Producing desirable firmness is important in manufacturing tofu from soybeans. This study’s objective was to explore the environmental impact (location and year) on soybean chemical components and identify the correlations between chemical composition and the firmness of tofu made from soybeans planted in three locations over two years. Seventeen soybean Plant Introductions (PI) from the USDA Soybean Germplasm Collection and eight check varieties were planted in Mississippi, Virginia and Missouri in 2017 and 2018. Protein subunit composition, protein secondary structure, phytic acid content, Ca2+ and Mg2+ content were determined. The result showed that A3 subunit content was …


Evaluating The Effects Of Pine And Miscanthus Biochar On Water Activity And Escherichia Coli Populations In Commercial Broiler Litter, Christopher Austin Marty Dec 2021

Evaluating The Effects Of Pine And Miscanthus Biochar On Water Activity And Escherichia Coli Populations In Commercial Broiler Litter, Christopher Austin Marty

Theses and Dissertations

The decrease in subtherapeutic antibiotic administration in poultry has increased the need to address production challenges caused by pathogens, such as E. coli. One potential way to improve bird health and reduce bacterial infection is through the addition of litter amendments that absorb moisture. Biochar (BC) has previously been shown to increase water holding capacity in poultry litter, but its effects on E. coli mitigation are unknown. The objectives of this research were to 1) evaluate water activity of poultry litter amended with pine and miscanthus BC, and 2) determine the effects of different BC inclusion rates on litter …


Initial Characterization Of Prna From Burkholderia Ambifaria: Developing An Nadph-Dependent Activity Assay For Tryptophan Halogenation, Mahmuda Akter Dec 2021

Initial Characterization Of Prna From Burkholderia Ambifaria: Developing An Nadph-Dependent Activity Assay For Tryptophan Halogenation, Mahmuda Akter

Theses and Dissertations

Some bacteria produce a potent antifungal agent (pyrrolnitrin) from tryptophan using four dioxygen dependent steps to outcompete other microbes. Each step of this process is catalyzed by an oxygenase encoded by the prnABCD cassette. The first enzymatic step in pyrrolnitrin biosynthesis is the regioselective chlorination of tryptophan to form 7-chlorotryptophan. This halogenation is catalyzed by PrnA, a Flavin dependent oxygenase, which has been isolated and characterized from P. fluorescens. The pyrrolnitrin biosynthesis pathway (prnABCD) has been also observed in the Burkholderia genus. This thesis comprises my studies on the expression, purification, and characterization of PrnA from Burkholderia ambifaria. Beyond the …


Mitigation Of Herbicide Resistance Development Among Weed Species In Cotton And Peanut, Justin S. Calhoun Dec 2021

Mitigation Of Herbicide Resistance Development Among Weed Species In Cotton And Peanut, Justin S. Calhoun

Theses and Dissertations

Herbicide resistance development among weed populations in cotton and peanut is becoming increasingly difficult to manage. If resistant populations continue to persist, weed control practices for producers will become less efficient and more costly. The objective of this research was to evaluate alternative weed control techniques designed to mitigate herbicide resistance development for their agronomic and economic impact on weed management systems. Studies were conducted in 2019, 2020, and 2021 at multiple locations in Mississippi and Arkansas investigating multiple techniques including the addition of soil surfactants in herbicide tank mixtures, increasing SOAs utilized in peanut herbicide programs, applying non-labeled herbicides …