Digital Commons Network^™

A Feasibility Study Of Drilling Fluid Slippage For Wellbore Displacement, John Johnson

LSU Master's Theses

In the ideal plug-flow mode viscoplastic drilling fluids display uniform frontal velocity due to wall slippage (at very low flowrate limited by the fluid’s yield strength). The flow rate could be increased by raising the yield strength that would make the fluid best candidate for frontal displacement. Based on this concept the study qualifies wall slippage effect for wellbore displacement. Using a conceptual model of fluid motion between two parallel plates defines maximum velocity as a function of shearing rate and yield stress. Conversion to coaxial geometry gives practical formulas for fluid testing with rotational viscometer. A new analysis of …

Probing The Electrode-Electrolyte Interface Of Sodium/Glyme-Based Battery Electrolytes, Dodangodage Ishara Senadheera, Orlando Carrillo-Bohorquez, Ernest O. Nachaki, Ryan Jorn, Daniel G. Kuroda, Revati Kumar

Faculty Publications

Sodium-ion batteries (NIBs) are promising systems for large-scale energy storage solutions; yet, further enhancements are required for their commercial viability. Improving the electrochemical performance of NIBs goes beyond the chemical description of the electrolyte and electrode materials as it requires a comprehensive understanding of the underlying mechanisms that govern the interface between electrodes and electrolytes. In particular, the decomposition reactions occurring at these interfaces lead to the formation of surface films. Previous work has revealed that the solvation structure of cations in the electrolyte has a significant influence on the formation and properties of these surface films. Here, an experimentally …

Lithium Ion Speciation In Cyclic Solvents: Impact Of Anion Charge Delocalization And Solvent Polarizability, Ernest O. Nachaki, Daniel G. Kuroda

Faculty Publications

The increasing demand for lithium batteries has triggered the search for safer and more efficient electrolytes. Insights into the atomistic description of electrolytes are critical for relating microscopic and macroscopic (physicochemical) properties. Previous studies have shown that the type of lithium salt and solvent used in the electrolyte influences its performance by dictating the speciation of the ionic components in the system. Here, we investigate the molecular origins of ion association in lithium-based electrolytes as a function of anion charge delocalization and solvent chemical identity. To this end, a family of cyano-based lithium salts in organic solvents, having a cyclic …

Enhancement Of Applied Rice Breeding Programs: Exploring Factors Impacting Genomic Selection Accuracy And Discovery Of A Novel Gene For Grain Shape, Maria G. Montiel

LSU Doctoral Dissertations

Plant breeding is a crucial tool in addressing global challenges such as climate change, population growth, and the need for more resilient crops. Rice serves as a staple food for a significant portion of the global population and has served as a model crop for genetic and genomic studies. Genomic selection (GS) has become valuable tool in plant breeding, allowing breeders to predict breeding lines’ performance based on their genotypes. The training (TS) set is a central component of genomic selection and the optimization of the training set is crucial for efficient implementation of genomic selection. The first two objectives …

Research On 3d Printing Resin Exposure Properties And Its Application On Centrifugal Microfluidic Platform Based On Fluorescence Detection, Zheng Qiao

LSU Doctoral Dissertations

This dissertation encapsulates significant advancements in the field of SLA 3D printing and centrifugal microfluidics. Central to the research is the development of a novel mathematical model for predicting trapped resin thickness in SLA 3D printing, a groundbreaking contribution that addresses a critical aspect of printing intricate structures. This model, the first to establish a mathematical relationship for resin thickness, is rooted in a comprehensive study of the resin curing process. The research leverages the concept of 'critical dosage' for resin curing, leading to a more refined and theoretically grounded approach for calculating curing thickness. Experimentation further validates the model, …

Seeking A Uniform Approach To Trumpet Sound Concept, Coleman T. Scott

LSU Doctoral Dissertations

One of the most challenging aspects of trumpet playing that pedagogues must teach is how to produce a professional tone. Trumpet students are often good musicians, play correct notes and rhythms, and even have proficient technique. However, many are unable to consistently produce a tone comparable to that of a professional. There are a number of methods that can be utilized to improve a student’s tone quality. In my own teaching and in the teaching of many professionals, tone concept has been used as a catalyst for the improvement of tone quality. A students’ exposure to a professional-quality trumpet tone …

Surfactant-Specific Ai-Driven Molecular Design: Integrating Generative Models, Predictive Modeling, And Reinforcement Learning For Tailored Surfactant Synthesis, Miriam Nnadili, Andrew N. Okafor, Teslim Olayiwola, David Akinpelu, Revati Kumar, Jose A. Romagnoli

Faculty Publications

Molecular design is a critical aspect of various scientific and industrial fields, where the properties of molecules hold significant importance. In this study, a 3-fold methodology design is presented that leverages the power of generative artificial intelligence (AI), predictive modeling, and reinforcement learning to create tailored molecules with desired properties. This model synergistically combines deep learning techniques with Self-Referencing Embedded Strings (SELFIES) molecular representation to build a generative model that generates valid molecules and a graphical neural network model that accurately forecasts molecular properties. The Variational Autoencoder (VAE) coupled with reinforcement learning helps refine molecule generation based on targeted attributes. …

Magnetic Control Of Nonmagnetic Living Organisms, Ahmed Al Harraq, Min Feng, Hashir M. Gauri, Ram Devireddy, Ankur Gupta, Qing Sun, Bhuvnesh Bharti

Faculty Publications

Living organisms inspire the design of microrobots, but their functionality is unmatched. Next-generation microrobots aim to leverage the sensing and communication abilities of organisms through magnetic hybridization, attaching magnetic particles to them for external control. However, the protocols used for magnetic hybridization are morphology specific and are not generalizable. We propose an alternative approach that leverages the principles of negative magnetostatics and magnetophoresis to control nonmagnetic organisms with external magnetic fields. To do this, we disperse model organisms in dispersions of Fe3O4 nanoparticles and expose them to either uniform or gradient magnetic fields. In uniform magnetic fields, living organisms align …

Building The Church Of San Vitale In Ravenna, Italy, Sally S. Morgan

LSU Master's Theses

This thesis uses the evidence concerning the design and building of the Church of San Vitale in Ravenna to reconstruct, as far as it is possible, the sequence of decisions, activities, and methods that led to the construction of the church, made of bricks and mortar, and whose interiors are covered by glorious colored mosaics and marbles. The historiography on the Church of San Vitale begins with the historian Agnellus, who wrote the Liber pontificalis ecclesiae Ravennatis in the 830s to 840s. According to Agnellus and other sources, the Church of San Vitale was founded by Bishop Ecclesius around 525, …

“Everything Is Not What It Seems”: Discovering Public Relations In Business Sectors In Vietnam, Ba-Anh-Tu Truong

LSU Master's Theses

Vietnam is a shining star in emerging markets, with an annual economic growth rate of 6-7%. Its abundant labor supply, stable political climate, and geographic proximity to major global supply chains make it an ideal candidate for manufacturer planning in advanced economies such as the United States, Europe, Australia, Japan, China, and Korea. Investing in public relations and communication management, especially understanding the Vietnamese market, effectively prepares multinational corporations for future business expansion. This mission is difficult for academia and industrial professionals since Vietnam is a “silent country” in public relations research. To fill the gap, this thesis employs the …

All-Optical Probes Of Particle-Like Charge Migration Dynamics, Kyle A. Hamer

LSU Doctoral Dissertations

Particle-like charge migration (CM) is the coherent, back-and-forth motion of a positively-charged electron hole along the backbone of a molecule following a sudden ionization. CM in small molecules generally occurs on an Angstrom (10^-10 m) spatial scale and an attosecond (10^-18 s) timescale. I use time-dependent density-functional theory (TDDFT) to simulate CM modes in organic molecules, and to explore all-optical probes of this attosecond electron dynamics using high-harmonic spectroscopy (HHS). By leveraging my results from previous studies of two-center interferences in carbon dichalcogens, in which I separated the harmonic signal into contributions from individual Kohn-Sham orbitals, I first …

Post-Modeling Adjustments And Delivered Dose Verification Of The 6fff Beam Model Commissioned For The Monaco Treatment Planning System, Grant C. Debevec

LSU Master's Theses

External beam radiation therapy has been shown to be an effective treatment method for tumors and abnormalities of the spine and vertebral region. Treating the spine using a stereotactic body radiation therapy (SBRT) technique can reduce toxicity to the spinal cord. The 6 MV flattening filter free (6FFF) beam model is currently used to plan and calculate dose for SBRT treatment plans, and the treatment plans are delivered using a linear accelerator (LINAC).

The commissioned beam model represents an invariant component of a LINAC. For volumetric modulated arc therapy (VMAT) treatment plans, the multileaf collimator (MLC) positions are changing throughout …

The Oracle Of The Pig's Head, Taylor L. Denton

LSU Master's Theses

The Oracle of the Pig’s Head is a collection of two poems, a short story, and a novel centered around themes of the role of the feminine body in society, monstrosity, disgust, divinity, and human impact on the environment. Inspired by other works of eco-criticism, gothic literature, surrealism, Appalachian folklore, and Greco-Roman mythology, this collection explores how marginalized bodies interact in a world forever altered by climate change.

Denton is primarily interested in how severe climate change has influenced not only human’s overall relationship to the environment, but also how writers are meant to engage with a world riddled with …

Gut Microbial Dysbiosis Differs In Two Distinct Cachectic Tumor-Bearing Models Consuming The Same Diet, Lauri O. Byerley, Brittany Lorenzen, Hsiao Man Chang, William G. Hartman, Michael J. Keenan, Ryan Page, Meng Luo, Scot E. Dowd, Christopher M. Taylor

Faculty Publications

The impact of cancer cachexia on the colonic microbiota is poorly characterized. This study assessed the effect of two cachectic-producing tumor types on the gut microbiota to determine if a similar dysbiosis could be found. In addition, it was determined if a diet containing an immunonutrient-rich food (walnuts) known to promote the growth of probiotic bacteria in the colon could alter the dysbiosis and slow cachexia. Male Fisher 344 rats were randomly assigned to a semi-purified diet with or without walnuts. Then, within each diet group, rats were further assigned randomly to a treatment group: tumor-bearing ad libitum fed (TB), …

Reducibility Of Schrödinger Operators On Multilayer Graphs, Jorge Villalobos Alvarado

LSU Doctoral Dissertations

A local defect in an atomic structure can engender embedded eigenvalues when the associated Schrödinger operator is either block reducible or Fermi reducible, and having multilayer structures appears to be typically necessary for obtaining such types of reducibility. Discrete and quantum graph models are commonly used in this context as they often capture the relevant features of the physical system in consideration.

This dissertation lays out the framework for studying different types of multilayer discrete and quantum graphs that enjoy block or Fermi reducibility. Schrödinger operators with both electric and magnetic potentials are considered. We go on to construct a …

Improved Tensor Current Limit From B 8 Β Decay Including New Recoil-Order Calculations, B. Longfellow, A. T. Gallant, G. H. Sargsyan, M. T. Burkey, T. Y. Hirsh, G. Savard, N. D. Scielzo, L. Varriano, M. Brodeur, D. P. Burdette, J. A. Clark, D. Lascar, K. D. Launey, P. Mueller, D. Ray, K. S. Sharma, A. A. Valverde, G. L. Wilson, X. L. Yan

Faculty Publications

A precision measurement of the β+ decay of B8 was performed using the Beta-decay Paul Trap to determine the β-ν angular correlation coefficient aβν. The experimental results were combined with new ab initio symmetry-adapted no-core shell-model calculations to yield the second-most precise measurement from Gamow-Teller decays, aβν=-0.3345±0.0019stat±0.0021syst. This value agrees with the standard model value of -1/3 and improves uncertainties in B8 by nearly a factor of 2. By combining results from B8 and Li8, a tight limit on tensor current coupling to right-handed neutrinos was obtained. A recent global evaluation of all other precision β decay studies suggested a …

Mind The Time: A Synthesis Of Pedagogical Approaches For Improving Rhythm And Meter For Instrumentalists As Applied To Bassoon, Annalea Milligan

LSU Doctoral Dissertations

Rhythm is imperative for the performing musician. This project aims to provide bassoonists with a resource for a rhythmic or metric-focused approach to their applied study. Pedagogical resources for improving rhythm in music through the lens of four categories are identified: experiential, pattern and phrasing, mapping, and repetition. Exercises created from a synthesis of each pedagogical approach demonstrate possible application to bassoon literature by exploring the ways in which an intentional awareness of rhythm can improve technical playing and build practice and performance confidence. By emphasizing the importance of rhythm, its components, and the various approaches to teaching and understanding …

Assessment Of Engineering Performance And Environmental Impacts Of High Reclaimed Asphalt Pavement (Rap) Asphalt Mixtures In Flexible Pavements, Ibrahim A.I.E. Elnaml

LSU Doctoral Dissertations

Due to the critical role of asphalt pavements in national infrastructure development, there is a pressing need to investigate more sustainable materials and approaches. The use of natural aggregates and asphalt binders in asphalt pavement presents sustainability challenges due to the depletion of finite resources. Recycling Asphalt Pavement (RAP) offers a promising sustainable solution by substituting virgin aggregates and asphalt binders with recycled ones. However, increasing RAP contents in asphalt mixtures (>25%) can lead to premature cracking, insufficient durability, and limited longevity due to the presence of aged RAP-asphalt binder. To address these concerns, the application of novel recycling …

Finite Monodromy And Artin Representations, Emma Lien

LSU Doctoral Dissertations

Artin representations, which are complex representations of finite Galois groups, appear in many contexts in number theory. The Langlands program predicts that Galois representations like these should arise from automorphic representations and many examples of this correspondence have been found such as in the proof of Fermat's Last Theorem. This dissertation aims to make an analysis of explicitly computable examples of Artin representations from both sides of this correspondence. On the automorphic side, certain weight 1 modular forms have been shown to be related to Artin representations and an explicit analysis of their Fourier coefficients allows us to identify the …

City Boy By Judd Greenstein: A Transcription From Chamber Quintet To Full Wind Band, Emmanuel Rodriguez

LSU Doctoral Dissertations

The goal of this project is to create a wind band transcription of the chamber work City Boy by Judd Greenstein. Greenstein describes his own music as being “built on contrasts and juxtapositions between the jittery, competing pulses of the New York City streets where he grew up and the placid landscapes of the rural farm land he now calls home.”1 His music is also influenced by his passion for contemporary popular music genres, specifically hip-hop and rap. This duality is a major aspect of Greenstein’s musical language, which he describes as “a genre- fluid musical infrastructures that endeavors to …

The Effects Of Global Temperature Change On Radon Exposure In Permafrost Areas, Melaan Bender

LSU Master's Theses

Global temperature increase leads to thawing of permafrost that protects local populations from radiation exposure by blocking radon-222 migrating into dwellings. This study aims at assessing the effects of permafrost thawing on the concentrations of radon in indoor air. An approach is developed to predict the evolution of the ²²²Rn concentrations by various processes including radon exhalation from thawed soil. It is found that as frozen soil thaws, more radon can enter dwellings, increasing the concentration of ²²²Rn in indoor air and elevating radiation-induced health risks. This study provides useful insight that will enhance understanding of potential climate …

Phonic Faces As An Intervention To Improve Decoding Skills Of Children With Persistantly Poor Decoding Abilities, Kayla Therese Martin

LSU Master's Theses

Background: Orthographic rules, phonological awareness, and the ability to process morphemes and phonemes from speech and language begins with verbal speech and the child unknowingly recognizes words from his or her environment as early as the senses can process their surroundings. Some children have difficulty integrating these processes to learn how to read. As Ehri (1979) mentions the importance of establishing mental processes, such as amalgamation and phonological recoding, are essential as a basis for establishing reading fundamentals. Decoding occurs through a complex integration of phonological and orthographic knowledge (Ehri 1992). Early readers typically have well-established amalgams for spoken words …

The Theory Of X-Ray And Neutron Interferometry Using A Modulated Phase Grating, Hunter C. Meyer

LSU Master's Theses

Grating interferometry exploits wave interference to simultaneously image multiple physical properties of an object and can be performed using X-rays or neutrons. The modulated phase grating interferometer (MPGI) is a recently developed interferometry system that allows for the simultaneous acquisition of attenuation, differential-phase contrast, and dark-field images, which highlight X-ray or neutron absorption, refraction, and small angle scatter, respectively. This interferometry system uses a single grating, with a relatively high period envelope function, to produce interference fringes that can be directly resolved by standard high resolution detectors. The grating is sampled at a relatively low pitch, to meet coherence requirements …

Spatial Mapping Of The Benthic Community And How It Is Used To Research Effects Of Dredging In Louisiana's Lake Borgne., Meghan Johnson

LSU Master's Theses

Benthic communities are vitally important for healthy aquatic ecosystems across Louisiana’s coast. Specifically in Lake Borgne, ecologically important species of fish like the Gulf Sturgeon (Acipenser oxyrinchus desotoi) rely on benthic macrofauna as their main food source. The purpose of this study was to determine the spatial landscape of biodiversity and abundance of the benthic macrofauna community in Lake Borgne. Environmental conditions played a key role in community structure during the study period (fall 2021 through summer 2023) with a major drought occurring in 2023. In 2023, the decline in the abundance of most benthic invertebrates and in …

Examination Of The Effects Of Ultraviolet Radiation On The Toxicity Of An Array Of Pesticides, Polyaromatic Hydrocarbons, And Pharmaceuticals Via In-Vitro Bioassays, Jessica R. Stephens

LSU Master's Theses

Chemicals are often released via anthropogenic means both intentionally and unintentionally into aquatic environments. The chemical fate of these compounds can vary greatly depending on numerous factors that can include but are not limited to salinity, pH, dissolved oxygen, and exposure to ultraviolet radiation. The goal of this study was to investigate the effect of UV radiation on the level of toxicity of different chemicals over time. Chemicals were selected based on previous studies of the toxicity of both parent and metabolites formed as a result of photolysis. Anthracene, phenanthrene, anthraquinone, dicloran, chlorothalonil, hydroxy chlorothalonil, benzobicyclon hydrolysate, and sertraline were …

Enhancement Of Soybean Growth And Disease Resistance Through Seed-Priming Strategy, Francisco Javier Valle

LSU Master's Theses

Disease pressure and other environmental stresses, especially increasing temperature and drought incidence, accompanied with global climatic change have presented hard challenges to Louisiana soybean producers. The objective of this study was to explore the efficacy of seed priming techniques as new alternatives to improve soybean crop protection to reduce the amount of yield losses caused by biotic and abiotic stresses. In this study, five chemicals were used as priming agents at different concentrations (0.1 mM, 1 mM, and 10 mM) to evaluate their effectiveness in enhancing disease tolerance and yield in soybeans. A seed priming procedure was developed by partially …

Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel

LSU Master's Theses

I aim to constrain the crustal thickness of the Sabine Block in the Sabine Uplift region of northwest Louisiana, using the frequency domain receiver function deconvolution technique followed by H-κ stacking. The passive margin on the southern edge of the North American continent experienced an active tectonic history, including the spreading events that led to the formation of the Gulf of Mexico. A previous study proposed the Sabine Block is a residual fragment of Proterozoic orogenic origin; however, its full extent and geometry are up for debate. It is now overlain by thick sedimentary sequences ranging from ~4-6 km deposited …

A Novel Goat Model To Characterize Male Fertility Following Paternal Cannabidiol Exposure, Ashlyn N. Brewer

LSU Master's Theses

Despite the increasing use of cannabidiol, both for medical and social purposes, the effect of cannabidiol on male fertility is poorly understood. Previous studies have been carried out in rodent models, but a large animal model does not exist at this time. This experiment proposes chronic cannabidiol (CBD) exposure using a goat model to understand the impact CBD has on male reproductive performance. The purpose of this project is to determine if daily exposure to CBD in male goats would impact reproductive parameters such as sperm quality and testosterone levels.

Two studies were conducted to determine the effects of CBD …

Spatial Behavior Of Hospital Visits By Hand, Foot, And Mouth Disease Patients In Nanchang, China, Zeliu Zheng

LSU Doctoral Dissertations

Hand foot mouth disease (HFMD) is one of the widespread transmissible diseases that target preschool children, especially in urban regions in East Asia. Understanding the travel patterns of the HFMD patients helps us understand how the spatial behaviors of patients vary across space and what are the underlying forces. It is essential for understanding the healthcare market and planning for resource allocation. Foremost, health behavior and outcome change significantly across geographic regions of various urbanicities (i.e., degrees of urbanization) due to the uneven distribution of healthcare resource. In addition, health studies in the U.S. often use hospital service areas (HSAs) …

Soundscape - A Guided Approach To Post-Tonal Horn Repertoire, Selena B. Boyda

LSU Doctoral Dissertations

More modern post-tonal works are being composed and it is imperative that horn players interpret the music as accurately as possible. Analyzing the music is a way one can interpret the music accurately. The purpose of this research is to develop a guided approach for interpretation of post-tonal horn repertoire using analytical techniques. Selected works analyzed and used are Olivier Messiaen’s “Appel Interstellaire,” Stanley Friedman’s Topanga Variations, and Jenni Brandon’s Dawn. Analytical techniques used include set theory, limited modes of transposition, contour relations, motivic patterns, modal analysis, and motifs.