Life Sciences Commons^™

Assessing The Flood Tolerance, Physiological Mechanism, And Nutrient Mitigation Potential Of Short Rotation Woody Crops Planted On Seasonally Flooded Marginal Land Of The Lower Mississippi Alluvial Valley, Thu Ya Kyaw

Theses and Dissertations

In 2019, the Mississippi River watershed had a record-long flooding, which was comparable with the 1927 Great Mississippi River Flood. This study leveraged this flooded condition to assess the flood tolerance of eastern cottonwood (Populus deltoides) and black willow (Salix nigra) planted as short rotation woody crops (SRWCs) on seasonally flooded marginal land of the Lower Mississippi Alluvial Valley (LMAV) in 2018. The survival/mortality prediction models developed by using hydrologic and environmental variables suggested that only high flood depth affected the survival of black willow. However, eastern cottonwood was threatened by flood depth, flood duration, and …

Improvement Value Of Forest Resources By Use Of Cottonseed Protein Meal As A Bio-Based Wood Adhesive For Hardwood Plywood Products, Edward David Entsminger

Theses and Dissertations

Literature shows that production of cottonseed adhesives is feasible to develop an environmentally friendly and competitive bio-based wood adhesive. Defatted cottonseed and water-washed cottonseed meals were prepared from glandless cottonseed and were used in adhesive formulations to produce three-ply yellow poplar (Liriodendron tulipifera) plywood panels as the first objective. These two cottonseed meals were compared with the properties of plywood panels made with an adhesive formulated from a commercial soybean meal, as a control. Adhesive resins were prepared from each protein meal with sodium metabisulfite (Na2S2O5) and one of two polyamido-amine-epichlorohydrin (PAE) wet strength agents, and the plywood panels were …

The Relationship Between Leadership Preference Of County Level Personnel Within University Of Missouri Extension And Their Level Of Employee Engagement, Jason C. Morris

Theses and Dissertations

The purpose of this study was to describe the perceived leadership style of the University of Missouri Extension Service county staff and their level of engagement and study the relationship between variables. Administrators with University of Missouri Extension Service can utilize this information to better serve Extension Staff and ultimately people throughout the state of Missouri.

The Vannsimpco Leadership Survey was used to measure the perceived leadership style of county level staff. The Utrecht Work Engagement Scale (UWES) was used to measure work engagement on three constructs: vigor, absorption, and dedication engagement. Demographic characterizes of county level staff was also …

Effects Of Temperature On Growth, Metabolic Rate, And Lower Dissolved Oxygen Tolerance Of Speckled Peacock Bass Cichla Temensis, Manuel E. Coffill-Rivera

Theses and Dissertations

I examined the effects of temperature (25, 30, and 35°C) on growth, standard metabolic rate (SMR), and lower dissolved oxygen tolerance (LDOT) of juvenile Speckled Peacock Bass Cichla temensis. Fish were acclimated to 150-L aquaria for 7 weeks before the growth, SMR, and LDOT experiments. The growth study lasted 58 days and fish acclimated to 25 and 30°C displayed similar growth rates, while fish acclimated to 35°C had very poor growth rates. The SMR and LDOT experiments were performed using intermittent respirometers. Fish acclimated to 25°C had the lowest SMR, followed by 30°C, and finally 35°C. The highest LDOT …

Behavioral And Histological Inflammatory Analysis Of A Single, Mild Traumatic Brain Injury And Repeated Subconcussive Brain Injury Using A Rodent Model., Anna Marie Clay

Theses and Dissertations

Subconcussive (SC) impacts have become a growing concern within the neuroscience community regarding the immediate and long-lasting effects of sports-related injuries. While a single low-level impact, i.e., a subconcussion, may not cause cerebral perturbations, it has been increasingly recognized that repeated SC exposure can induce deleterious effects. Therefore, determining the lower limits of systematic perturbation resulting from multiple SC impacts is of critical importance in expanding our understanding of cerebral vulnerability and recovery. Currently, there is a lack of correlation between a mild traumatic brain injury (mTBI) and repeated SC impacts with respect to injury biomechanics. Moreover, the cumulative threshold …

Evaluation Of Flood Damage On Cross Laminated Timber Wall Configurations, Mustafa Nezih Kaya

Theses and Dissertations

Greenhouse gas emissions are one of the critical factors that affect climate change, increasing flooding risk and threatening human life. The use of traditional construction materials is responsible for a higher percentage of global greenhouse gas emissions when compared to the use of sustainable materials in the construction industry. The substitution of current building materials with sustainable materials is essential to reduce greenhouse gas emissions and positively influence climate change when the current construction demand in the world is considered. Wood is one of the primary environmentally friendly construction materials in regard to high carbon storage and low carbon emissions. …

Novel Silviculture Practices For Non-Industrial Private Forest Landowners, Darcey Alyce Collins

Theses and Dissertations

Many landowners in the southeastern United States have invested in southern yellow pine plantations and managed them using traditional management schemes. However, non-industrial private forest landowners often have goals and challenges that make traditional management less desirable or possible. This thesis contains two projects that offer potential solutions for these landowners. The first project is a management option for landowners with small parcels that wish to manage pine plantations and proposes low-density management paired with crown lifting for the production of saw logs without commercial thinning entries. The second proposes a method for incorporating mixed-species management into already existing plantations. …

Evaluating Functional Zoning Based On Site Index To Achieve Competing Objectives Held By Family Forest Owners On Southern U.S. Pine Forest Tracts, Bradley S. Resch

Theses and Dissertations

Family forests comprise a significant portion of total forest lands in the southern United States and their owners frequently have multiple, competing objectives. This research evaluated the effectiveness of functional zoning based on site index on forest sizes relevant to family forest owners. A total of fifty family forests were randomly selected from counties in the East Texas Pineywoods region. Timber production and quail habitat were used as proxies for competing objectives. It was found that 80% of family forest parcels had sufficient site index heterogeneity to benefit from functional zoning. For forest parcels that could benefit from functional zoning, …

Evaluating Non-Invasive Environmental Methods For Detecting Tropical African Pangolin Species To Inform Conservation Actions, Ichu Godwill Ichu

Theses and Dissertations

Tropical African pangolin species are threatened throughout their range due to habitat loss and illegal take. Limited knowledge on distribution has rendered conservation efforts challenging. Methods commonly used for other wildlife species need to be tested for each pangolin species as each has variable ecologies requiring specific detection and monitoring techniques. This thesis evaluates the efficacy of two non-invasive environmental methods for detecting tropical African pangolin species, and consists of two complementary studies; a proof of concept study using soil sourced eDNA from a white-bellied pangolin enclosure in the Columbus Zoo, Ohio, to detect the species, and a field study …

Methods And Tools To Improve Performance Of Plant Genome Analysis, Drew Ferrell

Theses and Dissertations

Multi -omics data analysis and integration facilitates hypothesis building toward an understanding of genes and pathway responses driven by environments. Methods designed to estimate and analyze gene expression, with regard to treatments or conditions, can be leveraged to understand gene-level responses in the cell. However, genes often interact and signal within larger structures such as pathways and networks. Complex studies guided toward describing dynamic genetic pathways and networks require algorithms or methods designed for inference based on gene interactions and related topologies. Classes of algorithms and methods may be integrated into generalized workflows for comparative genomics studies, as multi -omics …

Assessing Non-Uniform Inbred And Hybrid Rice (Oryza Sativa) Population For Replant Decisions, Thomas William Eubank Iv

Theses and Dissertations

Optimal plant populations are critical in achieving high rice yields. The purpose of this research was to investigate yield penalties associated with inadequate, non-uniform plant populations for modern rice cultivars. Research was conducted at the Delta Research and Extension Center in Stoneville, MS, in 2019, 2020 and 2021. In one study, inbred, herbicide-resistant ‘CL153’ was drill-seeded at 73-18 kg ha^-1 after being mixed with inbred, herbicide-susceptible ‘Rex’ at 0-55 kg ha^-1. Likewise, hybrid, herbicide-resistant cultivar ‘CL XL7521’ was seeded at 29-8 kg ha^-1 mixed with hybrid, herbicide-susceptible ‘XP753’ at 0-21 kg ha^-1. At the …

The Employability Of State Ffa Degree Recipients In Alabama, Kailee D. Johnson

Theses and Dissertations

Many high schools have shifted from comprehensive graduation exams to a focus on College and Career Readiness. A common method used to determine when a student is college and career ready is a Career Readiness Indicator (CRI). Many CRIs demonstrate a benchmark learning goal for students. Among academic-based CRIs are Career and Technical Education (CTE) industry credentials. Credentials are just one way that agriculture classrooms contribute to student success. This study compiled existing research on CRIs and employability skills in CTE students to determine how the State FFA Degree could potentially fit into this category as well as highlight specific …

Utilizing Unmanned Aerial Systems To Sample Insects In Soybean, Marvin Merkl

Theses and Dissertations

To overcome some limitations of manual insect sampling in soybeans, an unmanned aerial vehicle (UAV) sampling platform was developed that could collect insects in a sweep net attached to the bottom of a UAV. Before this UAV sampling platform can be used to make management decisions, correlations with manual sweep net and/or drop cloth sampling methods are needed. This will allow action thresholds for the various pests to be calculated for the UAV sampling platform. To make the correlations, 87 soybean fields were sampled during 2020 and 2021 with each of 4 sampling methods, a UAV travelling 50-m, the same …

Sustainable Sidedress Nitrogen Applications For Early Corn And Cotton Crops Using Small Unmanned Aerial Systems, James Nolan Parker

Theses and Dissertations

Nitrogen run-off from agriculture have been linked to human health problems on a global level. Large-scale conventional producers struggle to redefine themselves as sustainable because reducing nitrogen (N) inputs without justification or validation may lead to severe profit losses. Small unmanned aerial systems (sUAS) sensing may allow for decreased N runoff. Failure to address this problem will exacerbate already excessive N runoff into the Mississippi River and beyond. The purpose of this study was to reduce fertilizer N input using sUAS technology to assess crop canopy needs. In 2020 and 2021, variable rate nitrogen (VRN) side-dress N application maps were …

Determining The Effects Of Elevated Carbon Dioxide On Soil Acidification, Cation Depletion, And Soil Inorganic Carbon And Mapping Soil Carbons Using Artificial Intelligence, Jannatul Ferdush

Theses and Dissertations

Soil carbon is the largest sink and source of the global carbon cycle and is disturbed by several natural, anthropogenic, and environmental factors. The global increase of atmospheric CO₂ affects soil carbon cycling through varied biogeochemical processes. The first chapter is a compilation of current information on potential factors triggering soil acidification and weathering mechanisms under elevated CO₂ and their consequences on soil inorganic carbon (SIC) pool and quality. Soil water content and precipitation were critical factors influencing elevated CO₂ effects on the SIC pool. The second chapter examines a detailed column experiment in which six soils …

Effects Of The In Ovo Administration Of The Poulvac E. Coli Vaccine In Layer Hatching Eggs On Hatchability, Hatchling Characteristics, And Early Posthatch Chick Performance, Lauren L. Lindsey

Theses and Dissertations

Avian Pathogenic E. coli can lead to infections in laying hens and wide-spread economic problems in the table egg industry. A vaccine widely used to combat APEC is the Poulvac E. coli vaccine, which is normally applied via spray vaccination. Application of this vaccine via in ovo injection has not been examined. The purpose of this series of studies was to determine the effects of injecting 50 μL of different dosages of the PECV into Hy-Line W-36 layer hatching eggs on the hatchability and characteristics of the hatchlings, and on the livability and characteristics of the chicks through 21 d …

Effectiveness Of Food-Grade Coating Treated Nets After Various Drying Methods At Controlling Mite Growth On Dry-Cured Hams, Sadie White

Theses and Dissertations

Tyrophagus putrescentiae, known as the ham mite, is the most difficult pest to control in the dry-cured ham industry. Food-grade propylene glycol coated nets have been studied as an alternative to conventional mite infestation treatments but were heavy and costly to ship. This study aimed to increase the ease of use of the coated nets via drying. Three drying treatments: oven dried for 7 min (OD7m), oven dried for 20 min (OD20m), and counter dried for 24 h (CD24h), were tested to determine the efficacy at controlling mites as well as the mechanical properties of the nets and sensory characteristics …

Effects Of Mass Death On Community Structure And Ecosystem Function, Abby Kimpton Jones

Theses and Dissertations

Death and decomposition are natural processes that are generally well-understood. However, large events of death, such as mass mortality events (MMEs) are increasing in frequency and their impacts on the ecosystem are largely unknown. These events may have both bottom-up effects from increased nutrient input as well as top-down effects from loss of an ecological functional group by the affected population. Different functional MMEs may result in different top-down effects, creating cascading effects. In Chapter 1, I test the hypothesis that scavenger and herbivore simulated MMEs generate novel bottom-up and top-down effects. Results indicate that MMEs have a significant effect …

Soybean Potassium Utilization During Reproductive Growth Stages In Response To Potassium Timing, Potassium Rate, Herbicide Injury, And Desiccation, Tyler Lawrence Richmond

Theses and Dissertations

Potassium (K) deficiency of soybean [Glycine max (Merr.) L.] is common throughout the Mid-Southern region of the United States. Visual symptoms of K deficiency may be absent or subtle during early and mid-reproductive growth stages. Correcting K deficiency in-season is problematic due to limited research. Information regarding soybean yield response to in-season fertilizer K application time is limited to growth stages prior to the onset of R1. Research is also limited on new higher yielding soybean cultivars. The objective of this study was to evaluate influences of in-season K application timing during reproductive growth stages on soybean yield. Field experiments …

The Impacts Of The Covid-19 Pandemic On The Food Security Of Mississippians, Hannah Noel Irwin

Theses and Dissertations

Mississippi leads the United States in food insecurity, with 15.3% of Mississippians experiencing food insecurity in a given year. To determine the impacts of the COVID-19 pandemic on the food insecurity of Mississippians, a survey containing the USDA Household Food Security Questionnaire was distributed to adult Mississippi residents. By employing the USDA Household Food Security Scale and the Foster-Greer-Thorbecke Methodology, this study finds that the food insecurity rate, food insecurity gap, and squared food insecurity gap have worsened in Mississippi since the beginning of the COVID-19 pandemic. Additionally, this study finds that households which were food insecure prior to March …

Assessing Virtual Free-Choice Agricultural Learning: A Mixed Methods Approach, Richard John Kennedy

Theses and Dissertations

Since the mid-19th century, agricultural museums and living history sites, first in Scandinavia and then in the United States and Canada, have provided historical, cultural, and, sometimes, scientific information about farming to visitors. Many of these visitors have been school children on field trips. Assessment of this learning, however, has been scant, particularly within the free-choice style inherent in these types of educational venues. At the same time, assessment of free-choice learning, often analyzed through the Contextual Model of Learning (Falk & Dierking 2000), has taken place at educational sites like zoos, natural history museums, and science centers. This study, …

Effects Of Anthropogenic Global Change On A Grassland Prairie Community, Carter Wolff

Theses and Dissertations

Anthropogenic global change is altering food web dynamics. Global change comprises factors, like temperature, sound, light and more. In this dissertation, I evaluate how two factors, sound and temperature, alter prairie communities. In Chapter 1, I test if sound influences grasshopper respiration rate, thereby altering diet. Some sound frequencies increased grasshopper respiration rate while others decreased respiration rate. Frequencies that elevated respiration rate led to grasshoppers consuming more carbohydrate-rich foods compared to protein-rich foods. This diet change stems from a carbon deficit due to increased respiration rate and could act as a mechanism by which sound pollution indirectly alters plant …

Inosine 5’- Monophosphate Derived Umami Flavor Intensity Of Beef Determination By Electrochemistry And Chromatography, Kezia Virellia To

Theses and Dissertations

The umami sensation contributes to beef flavor and acceptability. Inosine 5’- monophosphate (IMP) was the most abundant nucleotide in meat known to impart umami taste which thus far had been overlooked in meat flavor studies. The objectives of this study were to determine the umami taste threshold of inosine 5'-monophosphate (IMP), the effects of spiking IMP on the sensory descriptive attributes of various USDA graded beef strip steaks, and to differentiate beef by IMP content using electrochemistry. USDA Prime, Choice, and Select steaks were spiked with 0.3 and 0.6 mM IMP and analyzed chemically and organoleptically. Liquid chromatography-mass spectrometry and …

Maternal Nutrient Restriction And Melatonin Supplementation Alter Neurotransmitter Pathways In Bovine Fetal And Placental Tissues, Allison R. Harman

Theses and Dissertations

Nutrient restriction is a relatively common production insult to pregnancy in cattle. Recently, melatonin supplementation has been investigated as a possible therapeutic to rescue the negative effects of nutrient restriction. Neurotransmitters have been implicated as having negative programming effects in mouse and human pregnancies, manifested as metabolic and neurologic disorders. The role of neurotransmitters in fetal development has only begun to be understood in mice and humans. Neurotransmitters have not been analyzed in cattle, much less within the context of a compromised pregnancy. Brangus heifers were allotted to one of four treatments (ADQ-CON, RES-CON, ADQ-MEL, RES-MEL) in either Fall 2019 …

Introgression Or Incipient Speciation? Using Geometric Morphometrics And Gene Expression To Characterize Mouth Development In Larval June Sucker And Utah Sucker, Peter C. Searle

Theses and Dissertations

Understanding how biodiversity evolves is a major goal in evolutionary developmental biology because changes in developmental processes are tightly linked with evolutionary diversification. Heterochrony--alteration to the rate or timing of development--can significantly alter the appearance of descendant species. Heterochronic shifts in gene expression and associated morphological change may explain the morphological divergence between the threatened June sucker (Chasmistes liorus) and the sympatric Utah sucker (Catostomus ardens) in Utah Lake, UT, USA. June sucker are endemic to Utah Lake and have subterminal mouths adapted for pelagic feeding, while Utah sucker (Catostomus ardens) have ventral mouths adapted for benthic feeding. As larvae, …

Quantifying Aboveground Biomass In A Tropical Forest Using A Lidar Waveform Weighted Allometric Model, Alejandro Rojas

Theses and Dissertations

Our knowledge of the distribution and amount of terrestrial above ground biomass (AGB) has increased using lidar technology. Recent advancements in satellite lidar has enabled global mapping of forest biomass and structure. However, there are large biases in satellite lidar estimates which impacts our understanding of carbon dynamics, particularly in tropical forests.

Ni-Meister et al. (2022) developed a lidar full waveform weighted height-based allometric model which produced very good results in temperate deciduous/conifer forest in the continental US. The purpose of this study was to evaluate this biomass model in an African tropical forest using the Land Vegetation and Ice …

Use Of Seed Coating Technologies To Improve Cercocarpus Ledifolius (Curl-Leaf Mountain Mahogany) Seed Germination And Emergence To Reclaim Mine Lands, Emily M. Nielson

Theses and Dissertations

Globally, mining is vital to human interests, but its practice can cause landscape alteration which may look unnatural or engineered. The reintroduction of native plants to these areas is needed to restore the visual appeal and ecological function back into these altered mine lands. Cercocarpus ledifolius (curl-leaf mountain mahogany) is one desirable native species in the Intermountain West that is prized for its potential to grow on step and rocky hillsides and for the habitat it provides for wildlife. Unfortunately, C. ledifolius does not establish well from seed, which has been attributed to seed dormancy. The first objective of this …

Estimating Age In Mule Deer: Accuracy And Influence On Reproduction, Morgan S. Hinton

Theses and Dissertations

Accurate estimates of parameters and demographic rates of wildlife populations are crucial to management and conservation. One parameter of interest is age because it influences multiple demographic rates and behaviors including reproduction, dispersal, migration, and disease transmission. There are a number of methods used to estimate ages of wildlife. One of the most common methods used for mammals is evaluation of patterns in dental eruption and tooth wear. In the first chapter, we evaluate the accuracy associated with estimates of age from dental eruption and patterns of tooth wear for mule deer (Odocoileus hemionus). In the second chapter, we use …

The Effects Of Polymorphisms Of Viral Protein R Of Hiv-1 On The Induction Of Apoptosis In Primary Cells And The Characterization Of Twelve Novel Bacillus Anthracis Bacteriophage, Jacob D. Fairholm

Theses and Dissertations

Viral protein r (Vpr) of Human immunodeficiency virus type 1 (HIV-1) plays an important role in the ability of the virus to infect cells and cause disease. Two polymorphisms to Vpr have been shown to result in differences in disease progression in infected individuals. R36W tends to result in rapid disease progression while R77Q results in long-term non-progression. In order to better understand how these polymorphisms result in these different disease phenotypes, our lab has recently shown that in cell culture, the R36W polymorphism results in increased viral replication and greater induction of cell death. On the other hand, infection …

Anatomical And Biomechanical Factors Related To Running Economy In Uphill And Downhill Running, Mckenna Taylor

Theses and Dissertations

Much is known about running economy while running on level ground surfaces. However, with the dynamic of elevation changes during running, more research is needed to understand how various grades that will favor respective mechanics. PURPOSE: In this study, we focused on determining whether certain running mechanics and anatomy would predict a runner's oxygen uptake between downhill versus uphill running. METHODS: Twenty-one experienced runners completed six 5-min running trials (1 shoe x 3 grades x 2 visits) in a Saucony marathon racing shoe model (Type A) on level (3.83 m/s), uphill (+4% grade at 3.35 m/s), and downhill ( ˆ’4% …