Life Sciences Commons^™

Molecular Mechanisms Of Kynurenine-Mediated Lifespan Regulation In Yeast, Ryan E. Counterman Jobb

Theses and Dissertations

The kynurenine pathway is a highly conserved pathway that acts as the primary pathway for tryptophan catabolism and has been found to be involved in lifespan regulation across many diverse organisms. Caloric restriction (CR) is the only known dietary intervention to date that both increases the mean lifespan and the health span of multiple organisms, although the molecular mechanisms of these effects are not fully understood. There are known and sometimes contradictory relationships between the kynurenine pathway activity and the life- extending effect of CR but the crosstalk between the two is not well characterized. Understanding these relationships could lead …

The Impact Of Selected Winter Cover Crops On Soybean And Corn Yield, Seed Quality, And Economic Returns, Ashley Stockmaster

Theses and Dissertations

Cover crops are being used to reduce nutrient runoff from agricultural fields and to mitigate climate change. However, cover crops may reduce summer cash crop yields and affect seed quality early in adoption. Therefore, this study evaluated soybean and corn yield, seed quality, and a cost-benefit analysis following cover crops.

This study was conducted at the Illinois State University Research Farm and the Western Illinois University Research Farm to evaluate the impact of selected cover crops on soybean and corn yields and seed quality. The experimental design was a randomized block design replicated four times. Cover crop treatments consisted of …

Larval Environments Affect The Implementation Of The Sterile Insect Technique On Aedes Mosquitoes, Katherine G. Evans

Theses and Dissertations

Sterile Insect Technique (SIT) is an effective method for controlling pests and has been increasing in popularity to control Aedes mosquitoes. SIT involves inundating an area with sterilized male mosquitoes to reduce egg hatch and ultimately the number of wild adults. Previous research indicates that enacting mortality early in the larval life of Aedes mosquitoes can result in counter-productive effects, due to reduced competition among developing larvae. I hypothesize that the effectiveness of SIT at reducing adult populations is modified by densitydependent mortality and density-dependent growth among larvae. I performed two field-to-lab studies and developed an individual-based model to test …

Lower Extremity Individual Muscle Forces In Females During Loaded Hex-Bar Squat Jumps, Jadon Konkel

Theses and Dissertations

The purpose of this study was to describe the individual muscle forces and contributions to extensor force occurring during the propulsive phase of unloaded jumps in females and explore how these are influenced by increasing loads using the hex bar modality. Ten, college-aged females (height: 1.66 ± 0.09 m; weight: 68.63 ± 9.66 kg) with weightlifting experience performed hexagonal bar squat jumps at bodyweight (BW), BW+20% and BW+40% of 1RM. Traditional motion capture techniques were employed to collect dominate lower limb kinematics and kinetics. Individual muscle forces were estimated utilizing Static Optimization in OpenSim using a Gait2392 musculoskeletal model. Muscle …

Nutrient Transport And Transformation In Anaerobic Co-Digestion Of Crop Residues And Swine Manure, Shelby Stoner

Theses and Dissertations

Cover crops may improve soil quality, water quality, soil health, reduce soil fertilizer use, and increase nutrient availability to cash crops. The benefits of cover crops are discussed due to the below ground presence of cover crops, but the aboveground biomass can serve as a source of sustainable energy through anerobic digestion. The nutrients in the above ground biomass can also be recycled and reused through land application of digestion effluent. We have tested anaerobic co-digestion of different biomass feedstocks: cover crops, soybean stalk, and corn stover with swine manure using both small and pilot scale digesters. Nutrients, specifically NPK, …

Site-Specific Modification Of Antibodies Utilizing Microbial Transglutaminase For Improved Immunoassay Performance, Emily Beitello

Theses and Dissertations

Immobilization strategies used for fixing antibodies to solid phase surfaces significantly contribute to the antigen capture capacity and influences the performance and sensitivity of immunoassays. Traditional methodologies result in the random orientation and/or the weak attachment of immobilized antibodies. Different formats of immunoassays scope in applicability to many fields of research and everyday use. Improving the efficiency of immobilizing antibodies in immunoassays is a beneficial endeavor to increase assay sensitivity. Here, we investigated the use of enzyme-mediated conjugation of antibodies to facilitate a highly oriented immobilization. Microbial transglutaminase (mTG) catalyzes the covalent bond formation between a plethora of primary amine …

A Novel Silver-Ruthenium-Based Antimicrobial Kills Gram-Negative Bacteria Through Oxidative Stress-Induced Macromolecular Damage, Patrick O. Tawiah

Theses and Dissertations

The rise in drug-resistant bacteria, together with the decline in antibiotic development, requires new strategies for infectious disease control. Gram-negative pathogens are particularly challenging to combat due to their outer membrane. This study highlights the effectiveness of the silver-containing antimicrobial AGXX® against the Gram-negative bacterium Escherichia coli. AGXX® is a promising silver coating that presumably kills bacteria through the generation of reactive oxygen species (ROS). However, neither AGXX®’s mode of action is fully understood, nor have its effects on Gram-negative bacteria or bacterial response and defense mechanisms towards AGXX® been studied in detail. Here, I report that the bactericidal …

Converting Cover Crop Biomass To Biogas And Volatile Fatty Acids, Tuba Yasmin Lubna

Theses and Dissertations

Cover crops are commonly used for their environmental benefits, including improved soil health and reduced soil erosion. However, there is limited use for the aboveground biomass, except for oilseed crops. The objectives of this study were to (1) characterize the selected winter cover crop biomass at three growth stages, (2) evaluate the biogas and volatile fatty acids (VFAs) yield, and (3) examine the concurrent alkali pretreatment and ensiling effects on biogas yield. Wild pennycress, golden pennycress, CoverCress^TM, annual ryegrass, cereal rye, pea, and clover biomass were harvested at three growth stages. Results showed that biogas yield increased with …

Stress And Behavior In Beef Calves During Weaning, Kathleen E. Tierney

Theses and Dissertations

Animal welfare in commercial livestock operations has been an increasing topic of concern. It is well known that stress can have significant behavioral and physiological repercussions. It is especially important in commercial operations to reduce stress, as animal efficiency is the leading priority. In an effort to reduce stress on animals and improve welfare in livestock operations, several studies have evaluated common husbandry practices. One of the most widely studied practices is weaning, which encapsulates the process of removing the young from the dam. Several studies have evaluated the effects of weaning on beef cattle through a variety of behavioral …

Survey And Comparative Analysis Of Pollinator Diversity, Abundance, And Foraging Activity Of Diptera And Hymenoptera In Selected Habitats Of South Texas, Melissa Villarreal

Theses and Dissertations

With the declining bee population, non-bee pollinators can serve as an alternative source for pollination. Diptera is a potential source of untapped pollinator resources based on their abundance and visitation rate, but they are understudied in the field of pollination ecology. This study aimed to characterize the pollinator community in selected areas of South Texas. It focused on the Diptera and Hymenoptera families to compare their diversity, relative abundance, foraging behaviors, environmental influences, and vegetation associations. Active sampling and line transect were used in the survey to sample the Hymenoptera and Diptera communities to their family taxonomic rank. Statistical analyses …

Quality And Sensory Characteristics Of Selected Freeze-Dried Foods After 50 Years Storage, Prithiviraj Jegannathan

Theses and Dissertations

Freeze-drying is a dehydration process that uses low temperature and pressure to remove moisture from food. With an annual market value of over $35 billion in 2023, freeze-dried foods are widely used in various situations requiring long-term storage such as military rations, emergency food supplies, and space exploration. Freeze-dried foods are becoming more popular for their quality, light weight, easy storage at room temperature, and quick rehydration. Moreover, many freeze-dried food manufacturers claim that their freeze-dried food products can last for 25 years or more. However, there are currently no published studies supporting such claims. Chemical, physical, and sensory properties …

The Influence Of Heat Therapy On Redox Signaling In Skeletal Muscle, Kimberly Miriam Richard

Theses and Dissertations

Reactive oxygen species (ROS) have been identified as crucial signaling molecules in skeletal muscle adaptations to exercise and signal for protective pathways within the myofiber. Pathological heat stress studies in animals demonstrate the ability of heat to increase ROS production in skeletal muscle. Limited data on the influence of therapeutic heat on ROS production and redox signaling in human skeletal muscle exists in the literature. The purpose of this study was to assess ROS production and redox signaling in human skeletal muscle following an acute, therapeutic bout of heat treatment. We hypothesized that heat would create an oxidized environment within …

Integrative Single-Cell Genomics And Machine Learning Methods For Tumor Microenvironment Characterization And Survival Prediction, Wenjuan Zhang

Theses and Dissertations

The tumor microenvironment (TME) comprises diverse cell types and plays crucial roles in cancer development and therapeutic response. Single-cell RNA sequencing (scRNA-seq) data quantifies gene expression at the single-cell level, enabling the dissection of heterogeneous cell populations in various biological contexts and diseases. In this work, we developed integrative single-cell genomics and machine learning approaches to characterize the TME and enhance patient survival prediction. We introduced a convolutional neural network (CNN)-based method, cnnImpute, to address the high proportion of missing data in scRNA-seq datasets. cnnImpute effectively imputes missing values while preserving the integrity of cell clusters, achieving superior performance in …

Next Generation Sequencing Based Profiling Of Genes In Patients With Syndromic Forms Of Retinitis Pigmentosa, Harshavardhini G

Theses and Dissertations

India is one of the largest populations in the world and is estimated to have a high prevalence of Retinitis Pigmentosa (RP). RP is clinically and genetically heterogenous, characterized initially as night blindness, leading to complete vision loss due to retinal degeneration. RP can occur in non-syndromic or syndromic forms, affecting other organs as observed in Bardet Biedl Syndrome (BBS) and Usher syndrome (USH).

BBS is characterized by RP, polydactyly, obesity, renal anomalies and learning difficulties. USH is characterized by RP and sensorineural hearing loss (SNHL), with variable presence of vestibular dysfunction. Nextgeneration sequencing (NGS) has become a cost-effective technology …

Effects Of Microbial Lipases On Parmesan And Feta Cheese Flavor Profiles, Erin N. Caswell

Theses and Dissertations

Lipolysis is crucial for cheese flavor development, as lipolytic enzymes convert fats into free fatty acids that enhance flavor. While Kid/Goat (KG) lipases are traditionally used in cheese production, microbial lipases like M. javanicus (MJ) and C. cylindracea (CC) provide vegetarian, cost-effective alternatives. This study compares the flavor, texture, and composition of Feta and Parmesan cheeses made with microbial lipases as a replacement for traditional lipase. Conventional cheese making techniques were used to make experimental batches of Feta and Parmesan cheeses using a standard KG lipase and two experimental lipases, CC and MJ, and comparing all three against a control …

Climate Change Impacts On Dryland Ecosystems, Tanner Tainui Aiono

Theses and Dissertations

Dryland ecosystems are some of the most prevalent ecosystems on Earth and have recently shown stress indicators from climate change. These water-limited systems are vulnerable to increases in temperature and changes in precipitation, especially when looking at carbon cycling dynamics across biological sol crusts and vegetation mortality patterns. This dissertation aims to 1) evaluate how precipitation dynamics, vegetation location, and microclimate conditions influence biological soil crust carbon conditions, and 2) evaluate how topographic influences drive patterns of plant mortality during prolonged drought on the Colorado Plateau. Using high-resolution monitoring of long-term NEE chambers, we found that intermediately disturbed biocrusts are …

Using Genomics And Transcriptomics As A Tool To Understand Unique Phenotypes Of Hemipteran Insects That Are Relevant To Agriculture And Public Health, Hunter Kelly Walt

Theses and Dissertations

In the past couple of decades, advances in genomic sequencing technology have caused an unprecedented increase in biological data. Because of the quantity and size of these datasets, the need for biologists with computational expertise also increased, and using these large genomic datasets has revolutionized the way we can answer biological questions. In this dissertation, I apply genomic and transcriptomic data to answer questions about insects of the order Hemiptera that are relevant to agriculture and public health. My dissertation mainly focuses on stink bugs (Hemiptera: Pentatomidae), many of which are agricultural pests, and bed bugs (Hemiptera: Cimicidae), which are …

Development Of Novel Nanocarriers With Multi Modal Action Against Lung Cancer, Gayathri K

Theses and Dissertations

Lung cancer ranks among the top causes of cancer-related deaths worldwide. The deteriorating environment and unhealthy lifestyle in the modern era has further contributed to the exponential increase in lung cancer incidence across the globe. Lung cancers fall under two major types based on the location of the tumour in the lung namely, small-cell lung cancer (SCLC) which is more aggressive, and non-small-cell lung cancer (NSCLC) which is more prevalent. Late diagnosis has been a major cause for poor prognosis as the cancer is detected only in an advanced stage.

Conventional therapies like chemotherapy, surgery and radiotherapy against lung cancer …

Innovative Methyl Bromide Alternatives: Efficacy Of Acetic Acid Coated Ham Nets And Carboxymethyl Cellulose Films In Inhibiting Mite Infestations On Dry-Cured Ham, Sawyer Wyatt Smith

Theses and Dissertations

Dry-cured hams may become infested with Tyrophagus putrescentiae (ham mites) during the aging process. Traditionally, methyl bromide (MB) fumigation has been used to control these infestations, but its phase-out due to environmental concerns has prompted the need for alternative methods. This study evaluated the effectiveness of acetic acid-coated ham nets and carboxymethyl cellulose (CMC)-based edible films with propylene glycol (PG) in mitigating mite infestations. Laboratory trials assessed the impact of these treatments on mite orientation, reproduction, infestation rates, and sensory quality. Results indicate that CMC films were effective at controlling mite growth and reproduction with minimal sensory impact. In contrast, …

Identification And Characterization Of The Antimicrobial Activities Of Pseudomonas Sp. Strain Wp18, Emma Suzanne Willis

Theses and Dissertations

Strain WP18 was isolated from disease suppressive soil of a soybean rhizosphere in the Mississippi Delta. Phylogenetic analysis supported that strain WP18 could represent a novel species within the genus Pseudomonas. This conclusion is supported by genome-wide bioinformatic analyses such as average nucleotide identity and genome to genome distance calculations. Further studies are needed to claim a novel bacterial species, which include cell fatty profiles, fingerprinting analysis, and polar lipid analysis based on the International Code for Nomenclature of Prokaryotes. Strain WP18 showed a broad-spectrum of antimicrobial activity against plant pathogenic bacteria and fungi that are economically important in agriculture, …

Identification Of Bacterial Species Composition And Diversity Of Chicken Breast Meat During Processing., Lizzie Raquel Zaldivar

Theses and Dissertations

Understanding the bacterial profile of chicken during processing is essential to identify spoilage-related bacteria. Using advanced methods like Oxford Nanopore sequencing, specific bacterial species on chicken meat can be identified. This study aimed to characterize bacterial composition and diversity on chicken breast during processing. Results showed a reduction in aerobic bacteria, E. coli, coliform, and lactic acid bacteria counts. However, three thermophilic bacteria, Anoxybacillus contaminants, Neobacillus thermocopriae, and Anoxybacillus flavithermus, dominated across processing steps. Notably, Pseudomonas species were undetected by conventional plating but identified via Nanopore sequencing, highlighting the need for molecular detection methods. Although antimicrobial interventions significantly reduced bacterial …

Development And Changes Over Time Of A Granola Bar Formulated With Sweet Potatoes, Meredith Kate Maynard

Theses and Dissertations

Sweet potatoes are a worldwide staple crop and granola bars are popular with consumers. This study aims to create a granola bar utilizing sweet potatoes and to assess its changes over time. Initial formulations tested minimum and maximum concentration of sweet potato (SP) puree, formulations, cooking type and time/temperature, humectants and preservatives. Bars containing 30 and 45% SP butter were chosen. Changes over time and descriptive sensory evaluation were conducted every 14d for 70d, with four treatments: a control bar and a bar with a preservative, each held at 25°C and 47°C. Water activity and moisture decreased by 0.05 and …

Effects Of A Snap-Ed Social Marketing Campaign On Behavior Change, Andrew Beall Cole

Theses and Dissertations

Introduction: This research studied the use of a social marketing campaign to address chronic diseases in the U.S., such as obesity, diabetes, hypertension and other cardiovascular diseases by assessing audience self-reported actions and evaluating message framing effects on participant intentions to change nutrition behavior and daily physical activity. Approach: Evaluate a social marketing campaign for effects on SNAP-Ed eligible clients and research message framing effects on audience’s intention to change health behaviors. Discussion: The HappyHealthy social marketing campaign launched in 2018 by Mississippi State University Extension. Outcome evaluation data (collected 2023) reported multiple correlations between core messages recalled and increased …

Evaluation Of Current Management Strategies For The Tarnished Plant Bug And Tobacco Thrips In Midsouthern Cotton, Hunter Lane Lipsey

Theses and Dissertations

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is an important economic pest of cotton, Gossypium hirsutum (L.), in the Midsouth region of the United States. An experiment was conducted to determine the impact of insecticide class loss on yield and Lygus populations in the recently commercialized ThryvOn cotton technology. Data indicated no significant yield loss when excluding any currently utilized insecticide class for tarnished plant bug management. An additional objective was to reevaluate the sampling interval necessary to scout ThryvOn cotton for Lygus. No significant differences were observed between a 3 or 7-day sample interval compared to plots …

Effects Of Eugenol And Carvacrol In Combination Against Salmonella In Hummus, Lauryn Ashley Heidelberg

Theses and Dissertations

Hummus consumption has risen but multiple foodborne outbreaks due to Salmonella contamination have been reported. Essential oils (EOs) eugenol and carvacrol have been found to inhibit the growth and survival of Salmonella in food products. The objective was to evaluate antibacterial properties of various concentrations of eugenol (EU) and carvacrol (CA), alone or in combination (EUCA) against Salmonella in vitro and in hummus. Eugenol demonstrated a MIC of 0.125 mg/mL and an MBC of 0.25 mg/mL, while carvacrol showed a MIC of 0.0625 mg/mL and an MBC of 0.125 mg/mL. In the hummus study, 2% EUCA was the most effective …

Evaluation Of Soybean (Glycine Max L.) Seed Inoculation With Bradyrhizobium Japonicum And Bacillus Subtilis On Yield And Root System Architecture: A Herbicide Carryover Perspective, Ncomiwe Andile Maphalala

Theses and Dissertations

Reducing herbicide carryover in soybean production is imperative to sustain future soybean cropping systems in Mississippi and the rest of the world. This research was conducted to determine the response of inoculated soybean to corn (Zea mays L.) residual herbicides. The herbicide treatments included aatrex (atrazine), callisto (mesotrione), lexar (atrazine+mesotrione+s-metolachlor), and steadfast (nicosulfuron+rimsulfuron) at 100%, 75%, 50%, and 25% of the total label rate. Inoculant treatments were Bradyrhizobium japonicum, Bacillus subtilis, and no inoculant. Bacterial inoculants positively impacted most shoot and root growth parameters, significantly increasing depending on the herbicide x inoculant treatment combination and its rate. B.japonicum alone and …

A Correlation Study Between Soil Selenium Levels And Diabetes Prevalence Across U.S. Regions: An Archival Data Analysis (2012-2018), Baoshan Wu

Theses and Dissertations

This study investigates the correlation between soil selenium levels and Type 2 diabetes (T2D) prevalence across U.S. regions between 2012 to 2018. Selenium, an essential trace element, plays an important role in antioxidant defense and metabolism. While appropriate selenium intake may protect against diabetes by improving insulin sensitivity and reducing oxidative stress, excessive intake can have adverse effects. This research analyzed the most recent data, from the Centers for Disease Control and Prevention (CDC) and the U.S. Geological Survey (USGS), for over 3,000 counties in the U.S. A correlation analysis model was used to determine the relationship between soil selenium …

Precision Reclamation For Improving Mine-Land Reclamation Using Plant-Soil Chemical Analysis And Geospatial Technology, Haley Moon

Theses and Dissertations

The objective of this research was to assess plant-soil relationships and evaluate the use of multispectral drone imagery in predicting revegetation potential and soil properties at mine-land waste rock dumps. Field sampling of soils and vegetation was conducted, followed by Bayesian statistical significance tests and linear discriminant analysis (LDA) to determine key soil variables influencing plant communities. Results indicated that pH and electrical conductivity (ECe) were significant factors in the LDA and identified several plant communities that were associated with similar soil types. In parallel, regression analyses were employed to correlate multispectral drone imagery with soil characteristics and plant cover. …

The Long Shadow Of Infection: The Long-Term Implications Of Herpes Simplex Virus And M. Tuberculosis Infection, Lydia Howell

Theses and Dissertations

Infectious diseases and autoimmune diseases, such as multiple sclerosis (MS) and type 1 diabetes (T1D), have traditionally been seen as distinct, with separate etiologies and courses of disease. Recent research has shown that infection and autoimmune disease are more closely woven together than previously thought; certain pathogens like Epstein-Barr virus and M. tuberculosis have been shown to cause long-term disruption to the immune system, for example (Bordignon et al 2011, #1) (Zhang et al 2023, #2) (Bjornevik et al 2023, #3). Conversely, a distinct pattern has emerged in developed countries where as rates of infection fall, rates of autoimmune disease …

Survey And Comparative Analysis Of Pollinator Diversity, Abundance, And Foraging Activity Of Diptera And Hymenoptera In Selected Habitats Of South Texas, Melissa Villarreal

Theses and Dissertations

With the declining bee population, non-bee pollinators can serve as an alternative source for pollination. Diptera is a potential source of untapped pollinator resources based on their abundance and visitation rate, but they are understudied in the field of pollination ecology. This study aimed to characterize the pollinator community in selected areas of South Texas. It focused on the Diptera and Hymenoptera families to compare their diversity, relative abundance, foraging behaviors, environmental influences, and vegetation associations. Active sampling and line transect were used in the survey to sample the Hymenoptera and Diptera communities to their family taxonomic rank. Statistical analyses …