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Structural Determination And Regulatory Mechanisms Of Rice Lipoxygenase-1, Lillie Ballanco, Nathaniel Gilbert, Adam Offenbacher

Distinguished Undergraduate Researcher Program

Lipoxygenases (LOXs) are non-heme iron containing enzymes that catalyze the oxygenation of polyunsaturated fatty acids (PUFAs) such as linoleic acid (LA). These lipoxygenase enzymes are found in both plants and animals. In humans, LOXs have been linked to inflammatory diseases such as asthma, atheroscelerosis, and allergic rhinitis. Plant LOXs have been primarily linked to the growth, development, and stress response of the plant. This paper focuses on Oryza sativa lipoxygenase-1 (OsLOX1), an enzyme found in rice (Oryza sativa). OsLOX1 has been associated with enhanced drought tolerance in rice and may play a role in regulating growth under water-limited conditions. Understanding …

Lsu General Catalog 2026-2027, Louisiana State University And Agricultural And Mechanical College

LSU General Catalog

The LSU General Catalog describes all undergraduate and graduate departments and programs with degree requirements and courses offered for each one. The LSU General Catalog includes information on registration and financial aid as well as academic services offered to all students

Cache-Conscious Sparse Matrix Dense Matrix Multiplication On Gpus, Haoqiang Guo

LSU Doctoral Dissertations

Over the past decade, high-performance deep learning has evolved into a critical research domain, driven by the demand for efficient models and high inference throughput. Deep learning architectures have shifted from stacked convolutional layers to transformer-based models, while pruning techniques and graph-structured data have established sparse matrix–dense matrix multiplication (SpMM) as a fundamental kernel—particularly in graph neural networks (GNNs). Modern GPUs, with their massive parallelism and high-bandwidth memory, offer immense potential for accelerating these workloads. While SpMM implementations using the compressed sparse row (CSR) format remain common to avoid conversion overhead, preprocessing-based methods have recently demonstrated superior potential. In GNN …

Investigating The Fatigue Behavior Of Inconel 939 And Inconel 718 Through Micromechanical Testing, Mohammad Hossein Shahini

LSU Doctoral Dissertations

A detailed evaluation of fatigue crack growth (FCG) in a silicon-modified Inconel 939 alloy, fabricated via laser powder bed fusion additive manufacturing (L-PBF AM), was performed using cyclic bending tests on pre-notched microscale cantilevers with a cross-sectional dimension of 25 µm × 25 µm. To our knowledge, this study is the first to demonstrate that such microscale cantilever tests can effectively capture both the threshold and Paris-law regimes of FCG, despite the limited specimen size. The precise fabrication of these small-scale specimens allows for controlled fatigue crack propagation relative to the microstructure while minimizing the presence of volumetric defects. Notably, …

Role Of Cellular Stress Responses In Innate Immune Defense Against Acute Respiratory Infections, Amit Sharma

LSU Doctoral Dissertations

The endoplasmic reticulum (ER) stress sensor inositol-requiring enzyme 1α (IRE1α) is an important regulator of innate immune cells. However, its role in pulmonary innate host defenses remains poorly understood. This dissertation elucidates the dual, context-dependent role of IRE1α in host defense against methicillin-resistant Staphylococcus aureus (MRSA) pneumonia. We demonstrate IRE1α’s function as both a detrimental mediator of acute pathology and an essential facilitator of innate immune memory. Our work revealed that acute IRE1α activation during primary MRSA infection is detrimental. In lungs and alveolar macrophages (AMs), IRE1α is activated in response to MRSA infection. Consequently, IRE1α activation triggers a hyperinflammatory …

Advancing Louisiana's Cropping Systems: Sustainable Bioenergy Production, Cover Crops, And Technology Integration, Pedro R. Carrillo

LSU Doctoral Dissertations

The adoption of cover crops in Louisiana is lower than the national average, underscoring the need for region-specific research to address environmental challenges and demonstrate the short-term benefits of these practices within existing production systems. This research evaluated the integration of cover crops (CC) in energy cane (Saccharum spp.) and no-till cotton systems, focusing on their effects on soil health, nitrogen (N) management, and biomass production. Soil health indicators (SHIs), including enzymatic activities (β-glucosidase, β-glucosaminidase, and urease), protein N, inorganic N concentrations (nitrate and ammonium), soil organic matter (SOM), and microbial community composition assessed through ester-linked fatty acid …

The Influence Of Reactive Iron On Organic Carbon Preservation In Sediment Of The Mississippi River-Influenced Shelf, Manab Kumar Dutta, Neha A. Ghaisas, Kanchan Maiti

Faculty Publications

Reactive iron is a key driver of organic carbon preservation in marine sediments, but its participation in organic carbon remineralization complicates efforts to mechanistically constrain its role in preservation. To address this, we investigated the dual role of iron in the Mississippi River-influenced shelf sediment during low discharge (August 2016) and high discharge (May 2017). Duplicate sediment cores (30 cm depth) were collected from two stations; one core served as a natural reference, while the other was used for an incubation experiment. In the natural cores, reactive iron concentrations in the upper 9 cm were lower in August 2016 than …

Rapid Microbial Activity In Marine Sediments Significantly Enhances Silica Cycling Rates Compared To Abiotic Processes, Panagiotis Michalopoulos, Jeffrey W. Krause, Rebecca A. Pickering, Eleni Rousselaki, Kanchan Maiti, Martial Taillefert, Christophe Rabouille, Rudolph Corvaisier

Faculty Publications

Silicon, earth’s second most abundant element, cycles via biogeochemical processes in terrestrial and oceanic environments. The marine sediment-water interface is thought to divide biological-dominated (water) from abiotic-dominated (sediment) silica cycling processes. Studies indicate marine extremophile bacteria induce silica precipitation, but the quantitative importance of microorganisms in broader sediment silica cycling remains unexplored. We hypothesize that microorganisms significantly influence sediment silica cycling, challenging the prevailing divide of microbial importance. Within hours, sediment microbes expedited silica sequestration through rapid coupled dissolution/reprecipitation processes in marine deltaic sediment experiments. Using radiotracer silicon-32, we reveal that microbial mediation enhanced silica uptake, surpassing abiotic uptake by …

Elucidating The Role Of Marine Benthic Carbon In A Changing World, Cristina Schultz, Jessica Y. Luo, Damian C. Brady, Robinson W. Fulweiler, Matthew H. Long, Colleen M. Petrik, Jeremy M. Testa, Heather M. Benway, David Burdige, Marta M. Cecchetto, Isa Elegbede, Natalya Evans, Alexandra Frenzel, Kayla Gillen, Lisa C. Herbert, Heidi K. Hirsh, Gennadi Lessin, Lisa Levin, Kanchan Maiti, Sairah Malkin, Sarah L. Mincks, Stanley Nmor, Anh Pham, James Pinckney, Christophe Rabouille, Shaily Rahman, Subhadeep Rakshit, Nicholas E. Ray, Dalton K. Sasaki, Samantha A. Siedlecki, Christopher Somes, Aron Stubbins, Olivier Sulpis

Faculty Publications

The ocean plays a major role in controlling atmospheric carbon at decadal to millennial timescales, with benthic carbon representing the only geologic-scale storage of oceanic carbon. Despite its importance, detailed benthic ocean observations are limited and representation of the benthic carbon cycle in ocean and Earth system models (ESMs) is mostly empirical with little prognostic capacity, which hinders our ability to properly understand the long-term evolution of the carbon cycle and climate change-related feedbacks. The Benthic Ecosystem and Carbon Synthesis (BECS) working group, with the support of the US Ocean Carbon & Biogeochemistry Program (OCB), identified key challenges limiting our …

Integrating Human And Natural Systems From A Global Systems Perspective, John W. Day, William H. Conner, Katherine C. Ewel, Rachael Hunter, G. Paul Kemp, Robert Lane, Jay Martin, William Mitsch, Victor H. Rivera-Monroy, John Rybczyk

Faculty Publications

During his long career, Howard Odum focused on both conceptual and theoretical issues such as maximum power and the development of energy circuit language as well as ecosystem-level studies of natural systems and human interactions with these systems. He and colleagues carried out large macrocosm studies on a variety of ecosystems. We review here studies initiated by Howard Odum as well as whole system studies carried out by a number of post docs, his students and their students. We focus on studies involving John Day, Katherine Ewel, and William Mitsch. Ewel and Mitsch worked on fertilized cypress systems in Florida. …

Hurricanes And Human Health In Louisiana: Insights From Hurricanes Laura, Delta, And Ida, Shobha Kumari Yadav, Robert V. Rohli, M. E. Betsy Garrison, Elisabeth Ponce-Garcia, Nazla Bushra, Charleen Mcneill

Faculty Publications

Louisiana is one of the most disaster-prone states, with hurricanes ranking among the most destructive hazards. Hurricanes impede sustainability by straining hospital infrastructure, overwhelming emergency departments, and disrupting continuity of care. Louisiana’s healthcare system, characterized by high uninsured rates, limited rural access, and notable racial and socioeconomic disparities, is particularly vulnerable during disasters. This research explores trends of mental and respiratory health in Louisiana surrounding Hurricanes Laura (2020), Delta (2020), and Ida (2021). Analysis reveals a substantial increase in admissions after landfall of all three storms, with mental health conditions showing a larger surge than respiratory ones in already-vulnerable communities. …

Ocean–Atmosphere–Land Interactions And Their Roles In Climate Change, Biyun Guo, Chunyan Li

Faculty Publications

No abstract provided.

The Fungal Microbiota Modulate Neonatal Oxygen-Induced Lung Injury, Isaac Martin, Mary Silverberg, Ahmed Abdelgawad, Kosuke Tanaka, Brian A. Halloran, Teodora Nicola, Erin D. Myers, Jay P. Desai, Catrina T. White, Ibrahim Karabayir, Oguz Akbilgic, Laura Tipton, Samuel J. Gentle, Namasivayam Ambalavanan, Brian M. Peters, Luan D. Vu, Viral G. Jain, Charitharth V. Lal, Stephania A. Cormier, Joseph F. Pierre, Tamás Jilling, Ajay J. Talati, Kent A. Willis

Division of Basic Science Faculty Publications

Background: The immature lungs of very preterm infants are exposed to supraphysiologic oxygen, contributing to bronchopulmonary dysplasia (BPD), a chronic lung disease that is the most common morbidity of prematurity. While the microbiota significantly influences neonatal health, the relationship between the intestinal microbiome, particularly micro-eukaryotic members such as fungi and yeast, and lung injury severity in newborns remains unknown. Results: Here, we show that the fungal microbiota modulates hyperoxia-induced lung injury severity in very low birth weight premature infants and preclinical pseudohumanized and altered fungal colonization mouse models. Instead of fungal communities dominated by Candida and Saccharomyces, the first stool …

Contrasting Climate Oscillations Impacts On Phytoplankton In The Western And Eastern Tropical Pacific, Lina An, Edward A. Laws, Xin Liu, Ruiying Chen, Shanlin Wang, Shijian Hu, Yuchen Zhang, Yibin Huang, Feipeng Xu, Fei Chai, Bangqin Huang

Faculty Publications

Climate oscillations like the El Niño-Southern Oscillation and Pacific Decadal Oscillation significantly impact marine ecosystems. Traditionally, warm events are thought to suppress nutrient availability, reduce phytoplankton biomass, and change community structure. However, using two decades of field observations, remote sensing, Copernicus reanalysis, and Earth system modeling, we find very different responses in the western tropical Pacific. During El Niño, chlorophyll concentrations and diatom contributions increase, while La Niña reverses that trend. The further amplification of these El Niño-Southern Oscillation-driven contrasts by the Pacific Decadal Oscillation can be attributed to its effects on regional circulation, including the enhancement of eddy activity …

Light Cues Drive Community-Wide Transcriptional Shifts In The Hypersaline South Bay Salt Works, Margaret M. Weng, Benjamin Klempay, Jeff S. Bowman, Luke Fisher, Cyprien Camplong, Peter T. Doran, Susan Rundell, Jennifer B. Glass, Avishek Dutta, Alexandra Pontefract, Douglas H. Bartlett, Britney Schmidt, Sarah Stewart Johnson

Faculty Publications

The transition from day to night brings sweeping change to both environments and the organisms within them. Diel shifts in gene expression have been documented across all domains of life but remain understudied in microbial communities, particularly those in extreme environments where small changes may have rippling effects on resource availability. In hypersaline environments, many prominent taxa are photoheterotrophs that rely on organic carbon for growth but can also generate significant ATP via light-powered rhodopsins. Previous research demonstrated a significant response to light intensity shifts in the model halophile Halobacterium salinarum, but these cycles have rarely been explored in situ. …

Population Dynamics, Host Range, And Impact Of The Naturalized Weevil Ochyromera Ligustri: A Potential Biological Control Agent Of Invasive Ligustrum Sinense, Brandi H. Misiaszek

LSU Master's Theses

Invasive woody plants have become dominant components of many forest understories in the southeastern United States. These species can displace native species, disrupt ecosystem processes, and reduce biodiversity. Chinese privet (Oleaceae: Ligustrum sinense Lour.) is an invasive shrub distributed through the Southeastern United States. The ligustrum weevil (Coleoptera: Curculionidae: Ochyromera ligustri Warner) is a non-native insect that was first found in the U.S. on Ligustrum in 1959. This weevil is considered a potential fortuitous biological control agent of invasive Ligustrum spp. in the U.S. The objectives of this study were to evaluate O. ligustri as a potential biological control agent …

Exploring The Recognition Of Internalizing Problems Among Black Students: Delving Into The Youth Mental Health Help-Seeking Pathway, Marketta A. Adams

LSU Master's Theses

The mental health of Black adolescents is a growing concern, with high prevalence rates of internalizing disorders such as anxiety and depression. National studies report that nearly 47% of Black adolescents experience a mental health disorder by age 18, with over 60% reporting moderate to severe depressive symptomology. Despite these alarming rates, Black youth underutilize mental health services, often due to cultural stigma, limited access to culturally competent care, and under-recognition of their mental health needs. This study aimed to explore problem recognition as a key component in the mental health help-seeking pathway for Black adolescents in school settings. Grounded …

Effects Of Photo-Oxidized Crude Oil On Gulf Killifish Early Life Stages, Charles Campbell

LSU Master's Theses

Photo-oxidation of spilled crude oil generates polar compounds that can heighten toxicity to marine fish embryos. We investigated the effects of photo-oxidized crude oil on early life stages of Gulf killifish (Fundulus grandis) by exposing embryos under flow-through conditions to water-accommodated fractions of four oil treatments: fresh oil unexposed to either sunlight or weathering referred to as dark control (DC), a UV-light oxidized whole oil (LT), the polar fraction extracted from LT (Pol) and the remnants after extracting the Pol from LT (NP). Oil loadings of 0.38–3.00 g oil/kg water were tested. Total PAH concentrations and chemical profiles …

Sunburned Plankton: Ultraviolet Radiation Inhibition Of Phytoplankton Photosynthesis In The Community Earth System Model Version 2, Joshua Coupe, Nicole S. Lovenduski, Luise S. Gleason, Michael N. Levy, Kristen Krumhardt, Keith Lindsay, Charles Bardeen, Clay Tabor, Cheryl Harrison, Kenneth G. Macleod, Siddhartha Mitra, Julio Sepúlveda

Faculty Publications

Ultraviolet (UV) radiation can damage DNA and kill cells. We use laboratory and observational studies of the harmful effect of UV radiation on marine photosynthesizers to inform the implementation of a UV radiation damage function for phytoplankton photosynthesis in a modified version of the Community Earth System Model version 2 (CESM2-UVphyto). CESM2-UVphyto is capable of simulating UV inhibition of photosynthesis among modeled phytoplankton and ocean column penetration of UV-A, UV-B, and UV-C radiation. We conduct a series of simulations with CESM2-UVphyto using the Marine Biogeochemistry Library (MARBL) ecosystem model to understand the sensitivity of phytoplankton productivity to UV radiation. Results …

Computational Data Analysis, Kathryn S. Biles

LSU Master's Theses

Data science has emerged as a cornerstone of innovation, shaping an ever-expanding range

of professional careers. As technology advances and the volume of data expands expo-

nentially, the ability to extract meaningful insights from data has become indispensable

across industries. Far from representing a single career path, data science enables profes-

sionals in nearly every domain to make informed decisions, optimize systems, and drive

innovation. Yet, many high school students and incoming college freshmen have limited

exposure to data science fundamentals or the career opportunities they unlock. This is

the gap that Computational Data Analysis, a high school-level curriculum I …

Uav Remote Sensing For Assessment Of Conservative Management Practices In Maize-Soybean Cropping System, Aakriti Poudel

LSU Master's Theses

Sustainable agriculture practices promote cover cropping, which enhances nutrient management and impacts subsequent crop productivity in field crop rotations. Precision agriculture technology, particularly Unmanned Aerial Vehicle (UAV) remote sensing, enables a detailed evaluation of crop management. The studies were conducted in a maize-soybean rotation system with winter cover cropping and fallow management. The maize experiment investigated the effect of nitrogen application rates and cover cropping, using UAV-derived Normalized Difference Red-Edge (NDRE) to monitor crop performance. NDRE effectively captured the N response and the effect of cover cropping across growth stages, particularly during mid-season (55-81 DAP), where it showed a strong …

Integrating Cereal Rye Cover Crop And Herbicide Programs To Manage Glyphosate-Resistant Italian Ryegrass In The Midsouth, Bhupesh K. Dhaka

LSU Master's Theses

Glyphosate-resistant (GR) Italian ryegrass (Lolium perenne ssp. multiflorum) has become an economically significant weed management challenge in Louisiana row crop production systems. The problem is further exacerbated by the occurrence of biotypes with resistance to acetyl-CoA carboxylase (ACCase) and acetolactate synthase (ALS) inhibitors—herbicide sites of action (SOAs) commonly used for ryegrass control in soybean (Glycine max) and cotton (Gossypium). Field, greenhouse, and laboratory experiments were conducted during the 2023–2024 and 2024–2025 growing seasons at the LSU AgCenter Northeast Research Station in St. Joseph, LA, and at the LSU AgCenter Weed Science facilities in Baton …

Examining Private Landowner And Stakeholder Attitudes, Perceptions, And Knowledge Of Prescribed Fire In Louisiana, Chloe E. Crawford

LSU Master's Theses

Periodic fire was a primary driver of ecosystems across the Southeastern United States for millennia; however, fire suppression policies have become pervasive in the United States and led to increased fuel loads in forests as well as reduced biodiversity and reduced disease resilience. Prescribed fire presents a risk mitigation strategy and land management tool whereby practitioners can apply fire to the landscape in a controlled manner, thus reaping the benefits of fire while minimizing the risks associated with fire. Land in Louisiana is primarily privately managed and owned, so state-level conservation goals cannot be met without private landowner participation. As …

Narratives Of Vietnamese Teachers: Exploring Existential Givens Of Freedom, Meaning, And Isolation, Huy D. Nguyen

LSU Doctoral Dissertations

Drawing on Yalom’s framework of existential givens, this study explores how Vietnamese teachers experience existential freedom, existential isolation, and life meaningfulness. The notion of experience serves as the conceptual and interpretive foundation through which participants articulate these existential dimensions. Three participants were selected, and data were collected from online journal entries, vignette responses, and semi-structured interviews. Methodologically, it adopts intuitive inquiry as both conceptual lens and analytic process, integrating multiple modes of knowing and embodied understanding to explore how teachers imagine, experience, and interpret their work. To deepen interpretation, narrative structuring was incorporated to reveal the emotional and relational textures …

Versatile Nitration Of Bodipy Dyes Using No₂Bf₄: Effects Of Nitro Substituents On Spectroscopic And Self-Assembly Properties, Caroline Sarange Gwaro

LSU Master's Theses

This study explores the regioselective nitration of BODIPY dyes at the 2, 3- and 2,6-positions using nitronium tetrafluoroborate (NO₂BF₄), offering a high-yielding and mild synthetic route. The introduction of nitro groups significantly alters the dyes’ photophysical and self-assembly properties. Mono-nitrated BODIPYs exhibit hypsochromic shifts in absorption and emission spectra, increased dipole moments, enhanced Stokes shifts, and reduced molar absorptivity. In contrast, di-nitrated analogs show bathochromic shifts and decreased dipole moments in both ground and excited states. Spectroscopic characterization was performed using UV-vis and fluorescence spectroscopy, supported by density functional theory (DFT) calculations. Self-assembly behavior was investigated in polar (acetonitrile) and …

Detection Of Sweet Potato Feathery Mottle Virus Infection Via Remote Hyperspectral Imaging, Clayton Blake

LSU Master's Theses

In sweetpotato, global production exceeds 90 million tons annually, yet yields are threatened by numerous pathogens, including the potyvirus sweet potato feathery mottle virus (SPFMV). Virus infections can reduce yields by 25–40%, but surveillance is hampered by asymptomatic infections and the labor-intensive nature of detection. Hyperspectral imaging (HSI), combined with machine learning (ML), offers a promising pathway to scalable, non-destructive detection; however, studies focused on virus infection in sweetpotato remain limited.

This study demonstrates the feasibility of ML-enabled HSI for SPFMV detection under greenhouse conditions via a curated spectral library of two commercial cultivars, 'Beauregard' and 'Orleans', and the biological …

Establishing A Framework Of Best Management Practices For Sustainable Water Quality: Integration Of Technology And Remote Sensing, Mason L. Marcantel

LSU Master's Theses

Water quality security is a complex management issue that is constantly challenged by factors of seasonal variability in climate change, urban population growth, and agricultural intensification. These factors warrant the need for innovative technological adaptations to management practices that integrate remote monitoring, predictive modeling, and sustainable resource utilization. This study establishes a framework for sustainable water quality practices through the integration of remote sensing technology for urban wastewater treatment and agricultural irrigation systems. This dual-site research study explores seasonal water quality dynamics and technological interventions to create a more proactive approach to water quality security.

In the first study, water …

Evaluation Of Host Resistance To Rotylenchulus Reniformis In Sweetpotato Germplasm, Timothy S. Miller

LSU Master's Theses

The reniform nematode (Rotylenchulus reniformis) is an emerging plant-parasitic threat to sweetpotato production. Dissimilar from the galling caused by root-knot nematode infections, infections from the reniform nematode occur without visible damage to the root system. In the southern United States, heavily infested sweetpotato fields can lose up to 40% of their total yield. Growers rely heavily on fumigants and nematicides which provide inconsistent control and are not sustainable in the long-term. Past research has been more focused on the efficacy of chemicals than in the identification of host resistance or tolerance in sweetpotato germplasm. This study evaluated past …

Comparing The Consistency Between Age Estimations Across Various Three-Dimensional Model Creation Methods In An Attempt To Find A Practical Proxy For Physical Remains, Jeanne R. Wood

LSU Master's Theses

The purpose of this study is to determine whether digital three-dimensional models can serve as a viable alternative to physical human remains to allow continued research on fragile physical specimens. As digital three-dimensional models have become increasingly prevalent in anthropological and archaeological research, it is essential to assess their limitations and capabilities, particularly for subjective assessments that rely heavily on visual interpretation (Remondino & El-Hakim, 2006). While previous studies have focused on the use of digital three-dimensional models for quantitative measurements, their effectiveness for subjective analyses remains unclear (Cooper et al., 2003; Sholts et al., 2010; Stull et al., 2014; …

Competition And Soil Microbe-Mediated Interactions Following Dieback Of A Dominant Wetland Plant, Joseph Johnston, Aaron E. Devries, Rodrigo Diaz, Vinson P. Doyle, Tracy Elsey-Quirk, James T. Cronin

Faculty Publications

Plant invasions can have important consequences for the soil ecosystem which, in turn, can affect interactions with other plant species and impose serious constraints on restoration efforts. In the Mississippi River Delta (MRD), USA, widespread dieback of the dominant wetland plant, Phragmites australis, was followed by the colonization of invasive Colocasia esculenta (taro) in many areas. We conducted a common-garden experiment to investigate the competitive interactions among taro and two P. australis lineages prevalent in the MRD, Delta and European invasive (EU), and the role of taro-soil microbes in mediating those interactions. Plant types were grown alone or together and …