Life Sciences Commons^™

The Effects Of Acute Hyperosmolality On Immune Cell Functions And Nutrient Sensing, Joshua Granger

LSU Doctoral Dissertations

Hyperosmolar hyperglycemic syndrome (HHS) is a life-threating endocrine emergency commonly seen with type 2 diabetes. HHS has been identified to begin when hyperglycemia leads to glucosuria diuresis, which eventually leads to hyperosmotic conditions. However, hyperosmolality has not been considered as an initiator of HHS, although past research would suggest that it can initiate HHS, specifically through systemic inflammation and glucose insensitivity.

The first study examined the impact of exercise induced hypohydration effect on T-cell populations. After healthy participants reached hypohydration they were then rehydrated with water and monitored for 3-hours. Results indicated that rehydration attenuated the efflux of T-cells from …

Identification Of Quantitative Trait Loci (Qtl) Of Agronomic, Forage, And Milling Traits In A Southeastern Us Oat Association Panel, Kelly Joseph Arceneaux

LSU Doctoral Dissertations

Common oat (Avena sativa L.) is an allohexaploid (AACCDD, 2n = 6x = 42) crop grown primarily for human consumption and animal feed, and as a forage source worldwide. Southern oat breeding programs prioritize forage yield and regrowth, grain yield and quality, winter hardiness, and disease resistance. While spring oat breeding programs target grain yield and quality (beta-glucan content), winter oat breeding programs target forage yield and quality in addition to grain yield. Recent advances in genotyping by sequencing (GBS) and single nucleotide polymorphism (SNP) array have facilitated identification of quantitative trait loci (QTLs) and SNPs controlling various traits through …

Effect Of Implementing Best Management Practices (Bmps) On Productivity, Water Quality, Soil Health And Economic Return On Louisiana’S Sugarcane Production System, Krizzia L. Guardado

LSU Master's Theses

The constant soil cultivation alongside adverse weather in Louisiana has declined soil and water quality in sugarcane fields. Therefore, the integration of an effective conservation program must be assessed to sustain crop production. Best management practices (BMPs) promote soil health and improve water quality while achieving optimal crop development and cost-effective production system. A study was conducted at two different locations to document the benefits of BMPs (sweeping residue, variable N rate, and cover cropping) implemented collectively and individually compared to the standard farmer’s practices (FP) on sugarcane productivity, nutrient cycling, soil and water quality, and economic return . At …

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 …

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 …

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 …

Yeast Crf1p: An Activator In Need Is An Activator Indeed, Sanjay Kumar

LSU Doctoral Dissertations

Ribosome biogenesis is an energetically costly process, and tight regulation is required for stoichiometric balance between components. This requires coordination of RNA polymerases I, II, and III. Lack of nutrients or the presence of stress leads to downregulation of ribosome biogenesis, a process for which mechanistic target of rapamycin complex I (mTORC1) is key. mTORC1 activity is communicated by means of specific transcription factors, and in yeast, which is a primary model system in which transcriptional coordination has been delineated, transcription factors involved in regulation of ribosomal protein genes include Fhl1p and its cofactors, Ifh1p and Crf1p. Ifh1p is an …

Probing The Consequences Of Irreversibly Trapping Iron In Bacterioferritin Using Chemical And Genetic Approaches--An Omics Study, Leo S. Fontenot Jr.

LSU Doctoral Dissertations

Antibiotic resistant bacteria pose one of the most urgent threats to public health. Pseudomonas aeruginosa is a multi-drug resistant bacterium for which new antibiotics are urgently needed. My research is focused on understanding and validating iron metabolism as a target for antibiotic development by analyzing the metabolic profiles of iron-starved P. aeruginosa cells caused by irreversibly trapping iron in bacterioferritin. Iron is an essential nutrient for bacteria; however, the reactivity of the Fe²⁺ ion and insolubility of the Fe³⁺ ion present significant challenges to bacterial cells. Iron storage proteins oxidize Fe²⁺ using O₂ and H_{2 …}

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, …

Structural And Functional Characterizations Of The Two Mini-Ferritins In Pseudomonas Aeruginosa Revealed The Coexistence Of A Classic Dps (Pa0962) And A Dps-Like (Pa4880) Protein, Rajapaksha Pathirannahalage Nimesha Hansani Rajapaksha

LSU Doctoral Dissertations

In the P. aeruginosa genome, gene PA0962 codes for a probable DNA-binding protein from starved cells (Pa Dps). Pa Dps is assembled from 12 monomers, each consisting of a four-helix bundle fold typical of Dps proteins. A subunit dimer of Pa Dps harbors two ferroxidase centers. Assembly of a dodecameric structure of Pa Dps is favored by the presence of divalent metal ions and at pH 6.0 in the absence or presence of divalent cations. Pa Dps is unable to form the large DNA-protein complexes typical of many Dps proteins. Instead, Pa Dps acts on plasmid DNA to form relaxed …

Quality And Consumer Acceptance Of Shrimp Nuggets As Affected By Shrimp Shell Powder Addition, Jorge Ortega

LSU Master's Theses

Approximately 6 million tons of shrimp are produced annually. However, about 45% of shrimp is discarded as waste (shell/head portions). This waste represents both environmental and economic challenges. This study was performed to explore the potential of utilizing shrimp shell powder (SSP) as a sustainable ingredient in shrimp nuggets. To determine the optimal SSP inclusion levels, a preliminary study involving 35 panelists who participated in two sessions was conducted to determine a Consumer Rejection-Tolerance-Threshold (RTT) using a probit-regression model (α=0.05, GENMOD procedure, SAS software). Rejection-Range (RR) was determined at 95% fiducial limits, which yielded the maximum acceptable %SSP. Subsequently, 105 …

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 …

Louisiana Agriculture Magazine, Fall 2023, Lsu Agcenter

Louisiana Agriculture

Hemp has been cultivated for thousands of years. It was grown widely in the United States until the mid-1900s, when laws limited the growth of hemp and later banned it entirely. Since the 2018 Farm Bill removed legal barriers to growing the crop, Louisiana created a structure to regulate hemp farming in 2019.

Because little information existed about hemp in Louisiana, the LSU AgCenter created the Industrial Hemp Working Group to study the crop, create production practices and help growers interested in this ancient plant.

This issue of Louisiana Agriculture focuses on the work of these researchers and the growers …

Evaluation Of Organic And Synthetic Herbicides Applications On Indicators Of Soil Health And Weed Suppression In A Conventional Cropping System In Louisiana, Caitlin Denux

LSU Doctoral Dissertations

Synthetic herbicides, with their varying modes of action, are well known for their efficiency in the suppression and control of weed species in U.S. agriculture. However, the consequences of using synthetic herbicides without attention to the surrounding environment can produce chemical run-off, changes in soil health and soil health conditions, and create herbicide-resistant weeds. These consequences have encouraged growers to find alternatives in their weed management programs. In this study, organic and synthetic herbicides were assessed on how well they performed in weed suppression surveys, and their potential effects on soil health indicators. Commonly used indicators include soil pH, β-glucosidase …

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 …

Assessing The Effects Of Live Oysters And Sampling Gear On Biodiversity Metrics Of Reef-Associated Benthic And Nekton Assemblages, Finella Campanino

LSU Master's Theses

Oysters are declining globally, resulting in an increase in oyster reef restoration, with many efforts prioritizing maintenance of reef-associated biodiversity. Understanding the role that reef-specific characteristics play in supporting biodiversity and how sampling gear influences measurements of biodiversity can inform design and management of restoration projects. I examined the relationship between live oyster volume and reef-associated benthic and nekton assemblages (hereafter reef assemblages) and how sampling gears influence our understanding of biodiversity on intertidal Crassostrea virginica reefs near Cocodrie, Louisiana. I quantified substrate characteristics, assemblages via trays, and water-column characteristics across four reefs and four seasons in 2022-2023, and compared …

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 …

An Observed Increase In Cardiovascular And Respiratory-Disease Related Hospitalizations And Mortality In An Area Surrounding A Hazardous Waste Thermal Treatment Plant, Liana Isabelle Dela Torre Baconguis

LSU Master's Theses

Particulate matter (PM) pollution is highly correlated with respiratory and cardiovascular disease incidence. The generation of oxidative stress is a major way by which PM can damage the body. Environmentally persistent free radical-containing PM are generated by combustion processes and are capable of exerting increased damage on the respiratory and cardiovascular systems due to their ability to remain stable and regenerate reactive oxygen species for up to five years. Clean Harbors, LLC operates a thermal treatment plant near the city of Colfax, LA in Central Louisiana. Its regular open burning of explosives causes disturbances to the community, such as loud …

Wave Attenuation Through Mangrove Forest Using Lidar Representation, Elizabeth Bogan

LSU Master's Theses

Mangrove forests can be found along the world’s intertidal tropical and sub-tropical coastlines. These forested wetlands provide many ecosystem services, including supporting coastal food chains, trapping sediment, and shoreline stabilization. Mangroves are also known for flood damage mitigation by dissipating waves and surge during flooding events. Thus, coastal communities declare a vested interest in the performance of the forest to mitigate flood damage. Physical models using artificial mangrove structures have shown that red mangrove-dominated fringe forests can protect built infrastructure by reducing wave height due to increased drag. One way to estimate the contribution of red mangrove (Rhizophora mangle) prop …

Nutrient Content And Bioactive Compounds In Ornamental Type Sweetpotatoes, Sandeep Kaur Sran

LSU Master's Theses

Abstract

The leaf and root composition of different cultivars of ornamental sweetpotatoes (‘Blackie’, ‘Kakura’, ‘Manihi’, ‘Makatea’, ‘Tahiti’ and ‘Tatakoto’) were analyzed, and the impact of various factors on the levels of nutrients, vitamins, antioxidants, phenolic compounds, sugars, and organic acids in these sweetpotato cultivars were determined. The principal macronutrients found in sweetpotato foliage and roots were nitrogen (N), potassium (K), phosphorus (P), magnesium (Mg), calcium (Ca), and sulfur (S). Nitrogen was the most abundant macronutrient among all cultivars in sweetpotato foliage, whereas potassium was the most abundant macronutrient in sweetpotato roots. The principal micronutrients found in foliage and roots were …

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. …

Morphological And Molecular Characterization Of The Olfactory System In The Formosan Subterranean Termite, Paula Castillo

LSU Doctoral Dissertations

The Formosan subterranean termite, Coptotermes formosanus, is a eusocial insect species. Its members live in colonies consisting of reproductive (queen and king) and non-reproductive individuals (workers and soldiers). Olfaction is an essential sense for the social life of many insects. However, in termites, little is known about how olfactory cues are perceived in the peripheral sensory system (antennae) and processed in the central nervous system (brain) to elicit different behavioral responses across castes. In this study, we investigated the olfactory system in all castes (soldiers, workers, and reproductive alates), from the antennal and brain morphology to the antennal gene …

Reef Fish Movement Dynamics And Recruitment To Artificial Habitat, Jade Carver

LSU Master's Theses

Artificial reefs provide critical habitat for fish in areas lacking benthic structure, yet our understanding of how artificial reefs function and develop is limited. Here, changes in reef fish community assemblages were monitored using baited remote underwater video (BRUV) surveys (n=6) before and after a new artificial reef was deployed. Movement of red snapper (Lutjanus campechanus, n=20) and gray snapper (Lutjanus griseus, n=20) between nearby platforms (n=3) and the new artificial reef was examined using acoustic telemetry, and residency was calculated for fish associated with platforms and the artificial reef …

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 …

The Role Of Metallothioneins In Copper Homeostasis In Arabidopsis, Matthew Vandal

LSU Doctoral Dissertations

Copper (Cu) is a transition metal that is an essential nutrient for plants and is required for a number of critical processes. Therefore, proper homeostasis of copper is vital for plant life and must be tightly regulated. Metallothioneins are small molecular weight proteins, rich in cysteine residues and have the capability of binding to several different transition metals such as copper. Cu induces the expression of MTs, therefore they are believed to be involved in Cu transport, however their true functions have yet to be resolved. T-DNA insertions were identified in four Arabidopsis MT genes expressed in vegetative tissues, and …

Evaluation Of Salvinia Weevil Establishment, Dispersal, And Environmental Pressures Impacting The Giant Salvinia Biological Control Program, Korey Danielle Pham

LSU Master's Theses

Giant salvinia (Salvinia molesta Mitchell), an invasive free-floating aquatic fern, invaded the Toledo-Bend reservoir along the Texas-Louisiana border in the 1990s. The rapid spread threatens critical ecosystems, economies, and cultural services by altering water quality, and impacting fishing, hunting, and navigation. To combat this issue, the LSU AgCenter has been rearing and distributing the salvinia weevil (Cyrtobagous salviniae Calder and Sands), which has demonstrated effectiveness in reducing giant salvinia populations within a matter of months to a few years. The first study assessed the impact of propagule pressure on salvinia weevil effectiveness in outdoor mesocosms and revealed that …

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 …

Integrating Cultivar Resistance And Entomopathogens For Pest Management Of Sweetpotato Weevil, Cylas Formicarius Elegantulus (Summers), Schyler M. Lee

LSU Master's Theses

Sweetpotato, Ipomoea batatas (L.) Lam, is the number one vegetable crop in Louisiana, producing 21,178 kg/ha in the year 2021. The sweetpotato weevil, Cylas formicarius elegantulus (Summers), is an economically important pest of sweetpotato. C. formicarius elegantulus females lay eggs into feeding holes on the storage root surface. Larvae then hatch and tunnel through the sweetpotato flesh where they complete their development. This cryptic-natured brentid can cause up to 100% yield loss when left unmanaged. The Louisiana Department of Agriculture and Forestry mandates protocols to limit C. formicarius elegantulus spread (e.g., clean seed, pheromone trapping, and quarantines); however, scheduled chemical …