Digital Commons Network^™

An Intersection Of Science & Art: Vitrification Approaches And Open-Fabricated Tools For The Biomedical Model Sea Hare, Aplysia Californica, Allyssa M. Oune

LSU Master's Theses

The California sea hare (Aplysia californica) is an important biomedical model for molecular neurobiology, electrophysiology, learning, and memory due to their well-mapped and large neurons and well-characterized learning capabilities. The National Resource for Aplysia (NRA, University of Miami) maintains large stocks of live animals and relies on regular shipments of wild-caught individuals to maintain genetic diversity. This is labor and cost-intensive, and environmental changes could alter the availability of wild animals increasing the need to preserve this genetic resource. One solution is vitrification, ultra-fast cooling which produces an amorphous glass that minimizes damage to cells. Aplysia californica presents …

Containerized Satsuma Mandarin Production Under Protective Screens As A Management Strategy, Anna Timmerman

LSU Master's Theses

Many of the world’s citrus growing regions are experiencing challenges related to citrus greening, also known as Huanglongbing (HLB) caused by the presumed bacterial agent Candidatus Liberibacter spp. HLB is vectored by the Asian citrus psyllid (Diaphorina citri) and through propagation of infected citrus material. HLB impacts tree health as well as fruit development, ripening, and quality of the resulting citrus fruit, often leading to an unmarketable product. Producers are growing citrus in high density orchards underneath protective screening material that excludes the Asian citrus psyllid, preventing new HLB infections. Four ultra-high containerized tree spacings of 2 feet …

Effects Of Fertigation Versus Palletized Fertilizer On Height And Caliper Growth In Oaks, Zachary M. Davis

LSU Master's Theses

The Covid-19 pandemic and ensuing lockdowns led to an increase in revenue and production for green industry products in early 2020. In Study 1. an evaluation of fertigation (liquid feed, quick release) and controlled release fertilizers (CRFs, slow release) were applied to container-grown (7 gallon) live oak (Quercus virginiana) and Nutall oak (Quercus nuttallii) trees (100% Liquid feed, 0% CRF, 67% Liquid feed, 33% CRF, 33% Liquid feed, 67% CRF, 100% Liquid feed, 0% CRF). Live oak trees fertilized with CRFs had increased stem calipers (>30%). Nuttall stem caliper and height were significantly increased by …

Effects Of A Major Hurricane On Dynamics, Structure, And Composition Of Mississippi River Delta Forests, Lance C. Umlang

LSU Doctoral Dissertations

Tropical cyclones recurrently influence coastal forests worldwide. Tree survival (resistance) and post-cyclone recruitment (resilience) can vary with cyclone intensity, producing differences in composition, arboreal structure, and dynamics among affected forests. Studies of tropical cyclone wind effects on coastal forests typically emphasize damage more than post-cyclone responses. We hypothesized that intense cyclones might produce large, stratum-dependent effects that prevent affected forests from returning to pre-storm conditions. We explored direct effects of major Hurricane Katrina and post-hurricane changes in oak-dominated bottomland and cypress/tupelo-dominated swamp forests within the inactive portion of the Mississippi River deltaic plain. Overall mortality was high (14-25%) but concentrated …

Productivity Of Wood Ducks, Black-Bellied Whistling-Ducks, And Hooded Mergansers Using Nest Boxes In Louisiana, Dylan L. Bakner

LSU Doctoral Dissertations

Resident female wood ducks (Aix sponsa) in the southeastern United States are managed through nest box programs, with the goal of enhancing local hunting opportunities. Historically, hooded mergansers (Lophodytes cucullatus) were the only other cavity-nesting waterfowl species in the southeastern United States known to use these nest boxes. However, the recent northward range expansion of black-bellied whistling-ducks (Dendrocygna autumnalis) has extended into the range of wood ducks and mergansers. All three species are brood parasites, potentially using one another as hosts for their parasitic eggs and impacting their reproductive output. My research evaluated the …

The Impact Of Participation In 4-H Camp On The Connectedness To Nature Of Urban 4-H Members, Derek S. Landrum

LSU Master's Theses

Overnight summer camps are beneficial experiences that provide 4-H members from urbanized areas the chance to experience the outdoors and appreciate nature. Previous research shows that time in the outdoors can increase connection to nature. Furthermore, connection to nature is associated with adoption of pro‑environmental behavior, lowering of negative emotions, and positive general well-being. For this thesis, the researcher is interested in finding out if participation in 4-H summer camp has a significant effect on participant’s connection to nature as measured by the Children’s Environmental Perceptions Scale (CEPS) and the Inclusion of Nature in Self Scale (INS). Previous work has …

Integrated Pest Management And Behavior Of Stored Grain Beetles, Ethan Doherty

LSU Doctoral Dissertations

The lesser grain borer, Rhyzopertha dominica, and the rice weevil, Sitophilus oryzae, are two of the most destructive pests of stored rice. Their management has relied heavily upon fumigant insecticides. However, amid growing concerns that fumigant-resistant pests are becoming widespread, there is an urgent need for diversified management techniques and integrated pest management. Here, we explored management techniques and the behavior of these beetles. Host plant resistance toward both beetles was evaluated for 13 varieties of rice. We found large differences among varieties for both beetles in all resistance measures. We found that while nutritional components of a …

Do Fishery Meeting Attendees Represent The Fishing Industries?, Dominique Seibert

LSU Master's Theses

Public meetings are a highly utilized tool for disseminating important or useful information. Many agencies rely on them to reach various stakeholders and community representation at these meetings is important. A substantial amount of research has been conducted on various aspects of public meetings including different techniques, factors impacting attendance, and representativeness, that is attendees’ opinions representing the opinions at-large. A noticeable gap in the research includes information on public fishery meetings, commercial fishing industries, and their members’ participation. With the U.S. commercial fishing industries supporting more than a million jobs and providing more than a 200-billion-dollar economic impact annually, …

Rangewide Migratory Connectivity And Migration Ecology In Swainson's Warblers (Limnothlypis Swainsonii) Derived From Multisensor Geolocators, Garrett Rhyne

LSU Master's Theses

Successful conservation of Neotropical migratory passerines requires a detailed understanding of their annual cycle ecology, including wintering and breeding distributions, migratory pathways and stopovers, and migratory phenology. It is also important to evaluate the extent of geographic isolation between separate breeding populations during the nonbreeding season, known as migratory connectivity. Swainson’s Warbler (Limnothlypis swainsonii) is a species of conservation concern that, due to their secretive nature and selection of dense forest habitats, is poorly studied and lacks migratory information. Our objective was to track Swainson’s Warblers across their breeding populations (Mississippi Valley, Coastal Plains, and Appalachian) to detail …

Black Experiences With Community Gardening In Southeast Louisiana, Kiarah Craft

LSU Master's Theses

Community gardens have been rising in popularity over the past few years (Mayers, 2023). In response to the COVID-19 pandemic, many people across the United States have decided that it is crucial to grow their own food and develop sustainability within their community. Historically, Black communities have been underserved and ignored, especially in relation to food security and community safety (White, 2019, Penniman, 2018). The purpose of this study was to collect information about the effects of community-based gardening programs on Black people in Southeast Louisiana. Additionally, the researcher would like to gain knowledge regarding the reasons that Black people …

Genetic Dissection Of Alkalinity Tolerance In Rice (Oryza Sativa L.), Lovepreet Singh

LSU Doctoral Dissertations

Alkaline stress is a major threat to rice production globally. The resources for genetic improvement of alkalinity tolerance in rice are limited. We performed genome-wide association study (GWAS) and QTL mapping integrated with whole genome sequencing and expression analysis to identify and confirm QTLs and candidate genes. We developed a near-isogenic line (NIL) population to fine map the two important QTLs. In GWAS experiment, we genotyped and phenotyped a panel of indica and japonica genotypes for alkalinity tolerance and identified genomic regions and candidate genes conferring alkalinity tolerance. Principal component analysis revealed that alkalinity tolerance score, shoot dry weight, and …

Evaluating Vaccine Management Strategies For Edwardsiella Ictaluri Infections In Zebrafish (Danio Rerio), Brandy Malbrough

LSU Master's Theses

Aquaculture is a globally important industry that faces significant challenges due to infectious diseases, which can result in substantial financial losses. In 2011, a new strain of Edwardsiella ictaluri emerged as a major pathogen affecting zebrafish in the ornamental fish industry, leading to high mortality rates and posing a severe threat to the sector. Vaccines provide potential benefits for disease prevention in aquaculture, particularly live-attenuated vaccines (LAVs), which induce strong host immune responses. Bacterial attenuation for vaccine development has evolved from serial passage to more targeted genetic modification techniques. However, regulatory constraints limit the availability of licensed LAVs for aquaculture. …

Neural Mechanisms Of Resiliency And Susceptibility After Repeated Social Defeat, Christy R. Wayne

LSU Doctoral Dissertations

Social defeat is a powerful experience leading to drastic changes in physiology and behavior, many of which are negative. For example, repeated social defeat in vertebrates results in reduced reproductive success, sickness, and behavioral abnormalities that threaten individual survival and species persistence. However, little is known about what neural mechanisms are involved in determining whether an individual is resilient or susceptible to repeated social defeat stress. I used a resident-intruder experiment in the African cichlid fish, Astatotilapia burtoni, to create and investigate the behavior and neural correlates of these two opposing groups. Resilient fish used both searching and freezing behaviors …

Susceptibility Of Spodoptera Frugiperda Populations In The Southern Region Of The U.S. To Common Bt Proteins And Performance Of A Dual-Gene Resistant Helicoverpa Zea Strain On Common Pyramided Bt Corn Traits, Tiago H. Da Silva

LSU Master's Theses

The fall armyworm (Spodoptera frugiperda) and corn earworm (Helicoverpa zea) are two polyphagous pests that, in the Americas, are targeted by transgenic corn and cotton expressing Bacillus thuringiensis (Bt) proteins. A previous study during 2011-2013 demonstrated practical resistance to Cry1F corn in S. frugiperda in the southeastern seaboard of the U.S., while resistance of H. zea to Bt corn and cotton containing cry1A and cry2A genes has widely occurred in the U.S. The first objective of this study was to investigate the current susceptibility status to four Bt proteins commonly expressed in Bt corn plants, including …

Evaluation Of A Nutritional Calming Supplement For Stress Management In Beef Cattle, Randall Mallette

LSU Master's Theses

Two studies were conducted to determine the efficacy of two formulations of a nutritional calming product, Placid 1.0 and Placid 2.0, at keeping beef cattle in a calm state when exposed to environmental factors that put them into an excited state. In the pilot study, nine crossbred beef heifers were orally drenched daily for three days with 60 mL of their respective treatments, pen scores and exit scores were recorded, and blood was collected for cortisol analysis. There were no treatment effects for either treatment on any of the measured behavioral parameters or serum cortisol concentrations.

The products were …

Molecular Identification Of Oomycete Species Associated With Woody Plants In Louisiana And Survey Of Oomycete Species Associated With Live Oak Trees Planted On The Louisiana State University Campus, Hamilton Crockett

LSU Master's Theses

Three Oomycetes genera, Phytophthora, Phytopythium and Pythium, contain many important plant pathogens. Historically, Phytophthora infestans, responsible for the great Irish potato famine, and Phytophthora ramorum, causal agent of sudden oak death disease, are the two better-known high impact pathogens. The LSU AgCenter Plant Diagnostic Center (PDC) has been isolating putative Phytophthora and related species from combined root and soil samples collected from various woody ornamentals and trees for over a decade. In August of 2016, Louisiana received torrential rains, which resulted in historic flooding in several southern parishes. During subsequent years, the PDC staff isolated a …

Interactive Effects Of The Partial Pressure Of Co2, Temperature, And Nutrient-Limitation On The Physiology And Growth Of The Coccolithophore E. Huxleyi Grown On A 12:12 L:D Cycle Of Illumination, James Bradley

LSU Master's Theses

I studied the interactive effects of pCO2, temperature, and nutrient limitation on the growth and physiology of the marine coccolithophore, Emiliania huxleyi. This was done to look at the effect of climate change factors on the widespread and abundant calcifying marine organism as a predictor of what the future has to hold. The strain of E. huxleyi (PnB 272 B10) was grown on a 12:12 L:D cycle of illumination and exposed to either high or low pCO2 under nutrient-replete or nitrate-limited conditions across a temperature range of 10–28C. I examined the direct and interactive effects of temperature, pCO2, and nutrient …

Differences In Plant Hormone Responses Between Arabidopsis Thaliana And Schrenkiella Parvula Facing Lithium Toxicities, Jifeng Li

LSU Doctoral Dissertations

Investigating stress responses in plants is central to plant development studies and crop research. Identifying mechanisms of plant abiotic stress tolerance and adaptation will be keys to relieve the conflict between an increasing global population and declining agronomic land. Studies on extremophytes and their genetic responses to environmental stress are a way to help understand how and why these extremophile plants can develop well under extreme environments including high salinity and heavy metal toxicity. The studies herein first focus on comparative responses at the genetic level to lithium toxicity between Arabidopsis thaliana and Schrenkiella parvula. Based on elemental quantification …

Characteristics Of Yogurt And Culture Bacteria As Affected By Ingredients That Help Treat Leaky Gut, Ricardo Jose Santos Aleman

LSU Doctoral Dissertations

At least 100 million people have leaky gut syndrome. This syndrome is associated with multiple health problems such as diabetes, celiac disease, asthma, multiple sclerosis, and inflammatory bowel disease, costing more than $3 billion per year to treat. L-Glutamine, quercetin, slippery elm bark, marshmallow root, N-acetyl-d-glucosamine (NAG), licorice root, maitake mushrooms, and zinc orotate have been reported to help treat leaky gut.

The objectives were to explore the characteristics of yogurt and culture bacteria as affected by ingredients that help treat leaky gut. In yogurt, the pH, titratable acidity, syneresis, viscosity, color, Streptococcus thermophilus, Lactobacillus bulgaricus, yeast and mold and …

Silica Concentrations In Dominant Vegetation Species Of Wax Lake Delta, Louisiana, Danielle M. Soileau

LSU Master's Theses

Coastal deltaic wetlands colonize dynamic environments and experience fluctuations of salinity, river connectivity, sediment dredging or deposition, and periods of inundation resulting in unique vegetation and soils. Louisiana’s coastline is experiencing enhanced loss of coastal deltaic wetlands in coastal basins where the Mississippi River no longer is connected to waterways and channels that would normally provide freshwater and sediments representing the abandonment phase of the delta cycle. There is a coastal basin in the central regions of the state, the Atchafalaya Bay, that is still in the active phase of delta cycle resulting in the growth of the Wax Lake, …

The Effectiveness Of Eye-Hand Coordination Training In Virtual Reality, Kelley Burger

LSU Doctoral Dissertations

Virtual environments (VE) and virtual reality (VR) through head-mounted displays (HMD) have been used to test and train eye-hand coordination skills in a way that is more immersive than traditional 2D video training. As this technology continues to evolve, researchers have sought to determine the degree to which these new technologies can augment training. This research attempts to expand the literature on sport skill training in VE and VR to elucidate the training protocols that support learning. The first study was designed to determine how a single session of occlusion training would affect football catching skills in VR. While adding …

Measuring Food Literacy Among Limited-Resourced Adults, Emelia Clement

LSU Doctoral Dissertations

Food literacy is the interrelated knowledge, skills and behaviors needed to plan and manage, select, prepare, and eat healthy food. It is positively associated with improved consumption of nutritious diets, and can be beneficial to limited-resource adults, who are often at risk for chronic diet-related diseases. Valid instruments for measuring food literacy in this population are scarce but urgently needed. The Eating and Food Literacy Behavior Questionnaire (EFLBQ) can be used to measure food literacy among limited-resource audiences.

Part one of this study aimed to determine the fitness of the EFLBQ to measure food literacy in limited-resource adults. A convenience …

Active Transportation, Context, And Community Participation: Engaged Citizens And Destination-Based Walking And Biking, Jessica Stroope

LSU Doctoral Dissertations

Active transportation is associated with many benefits, including improved health outcomes, higher commuting satisfaction, lower pollution, reduced traffic, and social capital. One understudied area of research on active transportation and social capital is the relationship between active transportation and community participation. Although prior work has established a connection, little is known about the contexts in which this relationship may occur, or about how active transportation may affect the relationship between a context and community participation.

The purpose of Chapter 3 is to examine how active transportation may mediate the relationship between perceptions of place and community participation. Significant work has …

Evaluating Abiotic And Biotic Factors Affecting Plant Succession Processes At Malheur Lake, Beth Boos, Sammy L. King

LSU Master's Theses

Arid wetlands are diverse systems that provide habitat for a variety of flora and fauna, including stopover and breeding habitat for migratory birds. In the western United States, these wetlands support a network of stopover sites on the Pacific Flyway, and due primarily to wetland loss and alterations, these areas are becoming more isolated. Malheur Lake is a shallow endorheic lake in eastern Oregon that supported a robust emergent marsh throughout most of the 20^th century. However, following large scale flooding in the 1980s, emergent vegetation was extirpated and has only reestablished in small patches. Our objective was to …

Integrating Germplasm Repositories Into Oyster Aquaculture Systems At The Pathway, Center, And Network Levels, Sarah R. Bodenstein

LSU Doctoral Dissertations

Germplasm repositories offer many potential benefits to commercial farm operations, including preserving genetic resources and increasing production capabilities. Aquaculture industries have yet to take advantage of repository storage despite decades of research evaluating cryopreservation protocols. Eastern oysters (Crassostrea virginica), for example, are a useful research species when addressing this problem. Oysters are an economically important aquaculture species and a high-throughput cryopreservation method for oysters already exists. To address the gap between protocol research and commercial application a different approach is necessary that can analyze the requirements of repository development at multiple organizational levels. The goal of this dissertation was to …

The Characterization Of Selected Α- And Β-Carbonic Anhydrases Of Arabidopsis Thaliana, Hiruni Weerasooriya

LSU Doctoral Dissertations

Carbonic anhydrases (CAs) are zinc-metalloenzymes that interconvert two inorganic carbon (Ci) species, CO₂ and HCO₃^-. In Arabidopsis thaliana, there are eight αCA genes, six βCA genes, three γCA genes, and two γCA-like genes. The majority of CA research in plants has focused on finding a link between CA activity and photosynthesis rates. Since the CA genes are expressed in different plant tissues and multiple CA isoforms are distributed among various organelles of the plant cell, I hypothesize that CAs facilitate CO₂ diffusion among cell compartments and maintain Ci pools for carbon-requiring reactions by interconverting …

The Regulation Of Autoimmunity Genes In Pancreatic Β-Cells By Nf-Κb, Thomas Malone Martin

LSU Doctoral Dissertations

Type 1 diabetes (T1D) is an autoimmune disease where the immune system targets the pancreatic islet beta-cells, which are responsible for insulin production and secretion, leading to a state of insulin insufficiency. Many of the molecular details of disease onset and progression remain poorly understood, including key aspects of cytokine signaling. Therefore, we have examined some of the consequences of inflammatory cytokine signaling as a critical module relevant to T1D. Using interleukin-1 (IL-1) signaling as a well-defined paradigm for inflammation, we investigated key components of this signaling pathway in pancreatic beta-cells. We identified ICAM-1, one of the proteins expressed in …

The Global Transcription Factor Fur Is Activated By Binding A [2fe-2s] Cluster To Maintain Iron Homeostasis In Escherichia Coli, Chelsey Rene Fontenot

LSU Doctoral Dissertations

Iron is an essential element for biological functions. Organisms have developed specific mechanisms to acquire, store, and export iron to manage intracellular iron homeostasis. These mechanisms are crucial not only for providing the cells with adequate iron for biological processes but also for ensuring that cells are not overloaded with excess iron, which is highly toxic. The Ferric uptake regulator (Fur) is a global transcription factor for maintaining intracellular iron homeostasis in bacteria. Previously, it was postulated that when the intracellular iron content is elevated, Fur binds ferrous iron to down-regulate the iron acquisition genes and up- regulate the iron …

Evaluating The Pesticide-Induced Outbreak Of Soybean Looper, Chrysodeixis Includens (Walker) (Lepidoptera: Noctuidae), In Louisiana Soybean, Scott Lee

LSU Doctoral Dissertations

Soybean looper, Chrysodeixis includens (Walker), has established itself as the primary lepidopteran defoliator in Midsouth soybean agroecosystems. Pesticide-induced outbreak events associated with this pest have been observed by soybean producers. The insecticides believed to prompt these incidents are routinely used for the control of other co-occuring pests, such as stink bugs. Outbreak conditions present soybean producers with conflicting management decisions for pests. Laboratory, greenhouse, and field experiments were conducted to provide a better understanding of insecticide usage impact on populations of C. includens and the arthropod community. To discern the potential mechanisms behind C. includens outbreak, a baseline for the …

Evaluation Of Reproductive Phenology, Space Use, And Ecology Of The Eastern Wild Turkey (Meleagris Gallopavo Silvestris) In West-Central Louisiana, Chad Argabright

LSU Master's Theses

Nest site selection is a driving demographic force behind eastern wild turkey (Meleagris gallopavo silvestris) populations. However, previous research was likely not focused on the actual time of nest site selection, considering that nest site selection is likely only able to occur on the day of the first egg being laid. My objective was to determine if selection for any vegetation characteristics was occurring on the first day of laying. I estimated the path taken from the roost to the nest on the first day of egg laying (i.e., laying path) using GPS data collected from 164 unique …