Digital Commons Network^™

Shape Memory Polymer-Based Multifunctional Syntactic Foams, Siavash Sarrafan

LSU Doctoral Dissertations

With the increase in popularity of shape memory polymers (SMPs), especially in applications such as aerospace, textile, biomedical engineering, and even structures, the weight of the material and the devices made with it has always been a crucial factor. Using the shape memory polymer as a matrix to make a syntactic foam is one of the best and most affordable approaches to creating a lighter material that still has the shape memory effect. The addition of particles of different stiffness, strength, and size, with variable fractions, creates a composite that enables engineering the mechanical, as well as other physical and …

Functional Domains Of The Hsv-1 Ul37 Protein In Virus Infectivity And Retrograde Transport In Neurons, Carolyn Clark

LSU Doctoral Dissertations

Herpes simplex virus type 1 is large alphaherpesvirus with 20 envelope proteins and 23 tegument proteins. Virus entry is via fusion of the viral envelope with cellular membranes mediated by a complex of viral glycoproteins. Glycoprotein B (gB) is the only fusogenic glycoprotein, while other viral glycoproteins and membrane proteins including gD, gH, gL, gK and UL20 membrane protein modulate gB’s fusogenicity. Previously, Our laboratory developed the HSV-1 (VC2) vaccines strain with partial deletions in the amino termini of gK (ΔgK(31–68)) and the UL20 membrane protein (ΔUL20(4–22)). VC2 enters epithelial cells only via endocytosis followed by release of the capsid …

Dicotomía: Context, Aesthetic, And Performance Of The Symphonic Works Of Margarita Luna García, Gabriela Sofía Gómez Estévez

LSU Doctoral Dissertations

Dominican women had an active role in the musical life and discourse of the Dominican Republic in the twentieth century and made substantial contributions as composers, performers, pedagogues, and scholars. Margarita Luna García (1921-2016), Dominican composer and pedagogue, was one of the most notable figures of avant-garde music in the Dominican Republic in the twentieth century. Numerous modernist trends converge in her works including serialism, indeterminacy, and graphic notation. Influenced by Paul Hindemith, Béla Bartók, Krzysztof Penderecki, and Dominican composer Manuel Simó, her works synthesize vernacular musical material and modernist techniques. Luna García’s orchestral works make use of folk rhythms, …

Utilizing A Text-Mining Approach To Investigate Consumers’ Perception Of Secondhand Fashion Consumption: Mass-Market Vs. Luxury Market, H M Rakib Ul Hasan

LSU Doctoral Dissertations

The dissertation aimed to investigate (i) the difference in consumer perception between the mass-market and luxury market of secondhand fashion services, (ii) determine the types of value and strategies that can be adopted into mass-market SHF from luxury SHF business platforms, (iii) investigate the word-of-mouth communication of mass-market SHF consumers, and (iv) investigate the consumer perception of the ‘quality’ and ‘fashionability’ of the mass-market SHF product. Two studies were designed to address the research questions due to the nature of available data. The data were collected from third-party consumer review sites where consumers can review their perception of secondhand fashion …

Loop Quantum Gravity Of A Spherically Symmetric Scalar Field Coupled To Gravity With A Clock, Rodolfo Gambini, Jorge Pullin

Faculty Publications

The inclusion of matter fields in spherically symmetric loop quantum gravity has proved problematic at the level of implementing the constraint algebra including the Hamiltonian constraint. Here we consider the system with the introduction of a clock. Using the abelianizaton technique we introduced in previous papers in the case of gravity coupled to matter, the system can be gauge fixed and rewritten in terms of a restricted set of dynamical variables that satisfy simple Poisson bracket relations. This creates a true Hamiltonian and therefore one bypasses the issue of the constraint algebra. We show how loop quantum gravity techniques may …

Kinetic And Chemical Effects Of Clays And Other Fillers In The Preparation Of Epoxy-Vinyl Ether Composites Using Radical-Induced Cationic Frontal Polymerization, Brecklyn R. Groce, Emma E. Lane, Daniel P. Gary, Douglas T. Ngo, Dylan T. Ngo, Fahima Shaon, Jorge A. Belgodere, John A. Pojman

Faculty Publications

Addition of fillers to formulations can generate composites with improved mechanical properties and lower the overall cost through a reduction of chemicals needed. In this study, fillers were added to resin systems consisting of epoxies and vinyl ethers that frontally polymerized through a radical-induced cationic frontal polymerization (RICFP) mechanism. Different clays, along with inert fumed silica, were added to increase the viscosity and reduce the convection, results of which did not follow many trends present in free-radical frontal polymerization. The clays were found to reduce the front velocity of RICFP systems overall compared to systems with only fumed silica. It …

Injectable Antioxidant And Oxygen-Releasing Lignin Composites To Promote Wound Healing, Swathi Balaji, Walker D. Short, Benjamin W. Padon, Jorge A. Belgodere, Sarah E. Jimenez, Naresh T. Deoli, Anna C. Guidry, Justin C. Green, Tanuj J. Prajapati, Fayiz Farouk, Aditya Kaul, Dongwan Son, Olivia S. Jung, Carlos E. Astete, Myungwoong Kim, Jangwook P. Jung

Faculty Publications

The application of engineered biomaterials for wound healing has been pursued since the beginning of tissue engineering. Here, we attempt to apply functionalized lignin to confer antioxidation to the extracellular microenvironments of wounds and to deliver oxygen from the dissociation of calcium peroxide for enhanced vascularization and healing responses without eliciting inflammatory responses. Elemental analysis showed 17 times higher quantity of calcium in the oxygen-releasing nanoparticles. Lignin composites including the oxygen-generating nanoparticles released around 700 ppm oxygen per day at least for 7 days. By modulating the concentration of the methacrylated gelatin, we were able to maintain the injectability of …

Development, Survival, And Fecundity Of Helicoverpa Zea (Lepidoptera: Noctuidae) On Five Weedy Host Plants Common Across The Mid-South Usa, James P. Glover, Maribel Portilla, Gadi V.P. Reddy

Faculty Publications

Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) is a highly mobile and polyphagous pest known to feed on over 300 cultivated and wild host plant species. Larvae cause significant economic damage to several commercial row crops over multiple generations each growing season. The objective of this study was to compare biological fitness of H. zea on 5 weedy host plants commonly found across the mid-south US. Crimson clover (Trifolium incarnatum L.), white clover (Trifolium repens L.), hairy vetch (Vicia villosa Roth), kudzu (Pueraria montana [Lour.] Merr. (all Fabaceae), and honeysuckle (Lonicera japonica Thunb.; Caprifoliaceae) were evaluated as primary food sources for H. …

Stellar Mergers With Hpx-Kokkos And Sycl: Methods Of Using An Asynchronous Many-Task Runtime System With Sycl, Gregor Daiß, Patrick Diehl, Hartmut Kaiser, Dirk Pflüger

Faculty Publications

Ranging from NVIDIA GPUs to AMD GPUs and Intel GPUs: Given the heterogeneity of available accelerator cards within current supercomputers, portability is a key aspect for modern HPC applications. In Octo-Tiger, an astrophysics application simulating binary star systems and stellar mergers, we rely on Kokkos and its various execution spaces for portable compute kernels. In turn, we use HPX, a distributed task-based runtime system, to coordinate kernel launches, CPU tasks, and communication. This combination allows us to have a fine interleaving between portable CPU/GPU computations and communication, enabling scalability on various supercomputers. However, for HPX and Kokkos to work together …

Apocalypse Then And Now: Narrative Influence And Thematic Subversion Of Victorian Literature In Modern American War Narratives, Douglas James Scully

LSU Doctoral Dissertations

In this dissertation, I argue that by looking at the lasting impact of Victorian war literature on a variety of modern media, one can see that an increased cultural awareness of trauma has led to less humane depictions of the traumatized. The multitude of Sherlock Holmes adaptations produced and set in various time periods and covering assorted wars serves as a strong example in my first chapter of how a Victorian-produced text can have a lingering impact, and the veteran Watson serves as a strong tool for adaptors to use when commenting on the shifting nature of war and the …

The Reality Of Teaching English Virtually: Esl Teachers' Perspectives And Experiences During The Covid-19 National Pandemic, Natalia Guerrero

LSU Doctoral Dissertations

This study examined the dilemma ESL teachers experienced as the educational system shifted from the usual modus operandi of in-person lessons to the uncharted virtual learning environment (VLE). ESL teachers, in one of the largest urban districts in Louisiana, accumulated additional roles and responsibilities that were unique to the teachers of the English learner (EL) population enrolled at their schools.

Data collected to answer the research questions were the product of single and focus group’s interviews with five ESL elementary and middle school teachers in Freedom District. State and district emergency response to COVID-19 guidelines, along with instructional artifacts, were …

Division I Softball Athletes' Perceptions On Stress, Coping, Performance, And Mental Health, Rhianna Weall

LSU Master's Theses

Collegiate athletes face numerous stressors in both athletic and academic areas of performance. Their perceptions of situations dictate coping responses and their ability to enact behavior or implement strategies to manage stress levels. This study investigated perceived stress and coping strategies using semi-structured in-person interviews with five current NCAA Division I softball players. Three main themes emerged from the interviews: (a) Pressure is Privilege, (b) Team Dynamic and Identity Development, (c) Softball-Centrism. In the first theme, pressure is viewed as a positive aspect and as an opportunity to perform in areas of high and low levels of confidence. Within the …

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 …

Inverse Machine Learning Discovered Metamaterials With Record High Recovery Stress, Adithya Challapalli, John Konlan, Guoqiang Li

Faculty Publications

Lightweight shape memory polymer (SMP) metamaterials integrated with high strength, high flexibility, and high recovery stress are highly desired in load carrying structures and devices. A grand challenge is that these desired properties have contradictory requirements, for instance between strength and flexibility, and between flexibility and recovery stress. In this study, an inverse design framework using statistical tools and machine learning models is developed to design thin-walled cellular structures with the desired properties. The discovered thin-walled cellular structures are 3D printed using a novel SMP, which exhibited excellent structural properties with record high specific recovery stress. For comparison purpose, lattice …

Optimization Of Host Cell-Compatible, Antimicrobial Peptides Effective Against Biofilms And Clinical Isolates Of Drug-Resistant Bacteria, Jenisha Ghimire, Robert J. Hart, Anabel Soldano, Charles H. Chen, Shantanu Guha, Joseph P. Hoffmann, Kalen M. Hall, Leisheng Sun, Benjamin J. Nelson, Timothy K. Lu, Jay K. Kolls, Mario Rivera, Lisa A. Morici, William C. Wimley

Faculty Publications

Here, we describe the continued synthetic molecular evolution of a lineage of host-compatible antimicrobial peptides (AMP) intended for the treatment of wounds infected with drug-resistant, biofilm-forming bacteria. The peptides tested are variants of an evolved AMP called d-amino acid CONsensus with Glycine Absent (d-CONGA), which has excellent antimicrobial activities in vitro and in vivo. In this newest generation of rational d-CONGA variants, we tested multiple sequence-structure-function hypotheses that had not been tested in previous generations. Many of the peptide variants have lower antibacterial activity against Gram-positive or Gram-negative pathogens, especially variants that have altered hydrophobicity, secondary structure potential, or spatial …

Removal Of Radionuclides Using Capacitive Deionization, Yusik Won

LSU Doctoral Dissertations

Severe nuclear accidents, including the Fukushima nuclear power plant accident, can lead to the discharge of large amounts of radionuclides into aquatic environments. Some radionuclides such as ¹³⁷Cs and ⁹⁰Sr have long half-lives and can remain in the environment for a long period of time. These radionuclides can be detrimental to humans and the environments because they can cause human and environmental exposure to ionizing radiation and because they can be bioaccumulated and biomagnified. Therefore, in case of a severe accident and a radioactive spill, it is important to quickly clean up and treat radioactively contaminated water to …

"Feeling Who I Am": Developing A Theory Of Intersectional Emotional Expression In The Workplace, Terrance Boyd

LSU Doctoral Dissertations

Scholars have studied how employs engage in emotional labor with customers, coworkers, and supervisors in the workplace for over twenty years (Grandey, 2000; Hochschild, 1983; Kim, Bhave, & Glomb, 2013; Thomas, Olien, Allen, Rogelberg, & Kello, 2018). A considerable amount of the emotional labor literature explores the impact of gender in the hypothesized relationships, largely positing that women engage more often in emotional labor and feel the consequences more severely than men (e.g., Scott & Barnes, 2011; Simpson & Stroh, 2004; Ward, McMurray, & Sutcliffe, 2020). Although important and enlightening, this approach is limited in recognizing the more complete spectrum …

Assessing The Nutritional Value Of Dubia Roaches (Blaptica Dubia) As A Feeder Insect In Reptiles, Elise Barras

LSU Master's Theses

Dubia roaches (Blaptica dubia) have emerged on the market as a high protein and low-fat alternative to other feeder insects for captive reptiles. However, much like other insects, dubia roaches naturally have an inverse calcium to phosphorus (Ca:P) ratio. Offering insects to reptiles that are deficient in calcium can lead to nutritional disease (e.g., nutritional secondary hyperparathyroidism). For dubia roaches to be a valuable feeder insect, their Ca:P ratio must be corrected. Several studies have assessed their nutritional composition, but no studies have manipulated the calcium content of these insects. Using a high calcium (8.3% calcium, dry matter) …

Image Analysis Methodology For Evaluating Coating Uniformity Of Drug-Coated Angioplasty Balloons, Allison Dobson Zieschang

LSU Master's Theses

Percutaneous transluminal balloon angioplasty (PTA) is a surgical procedure to treat peripheral artery disease, but restenosis causes suboptimal outcomes in many patients. Drug-coated angioplasty balloons (DCBs) were developed to reduce the risk of restenosis by delivering anti-proliferative drugs to the lesion. The efficacy of DCBs depends on factors like drug loading and drug release rate, both of which are directly impacted by the coating uniformity. This thesis evaluates the uniformity of DBCs using fluorescence microscopy, scanning electron microscopy (SEM), qualitative analysis, and an image processing algorithm. Uniformity was quantified by three measurements: histogram standard deviation, histogram percentage of coverage, and …

Influence Of Metabolic Interventions On Animal Aging And Lifespan, Bhaswati Ghosh

LSU Doctoral Dissertations

Aging is associated with metabolic rewiring. Most lifespan-extending longevity interventions target metabolic pathways. Genetic or pharmacological metabolic approaches that mediate longer lifespan and healthspan, are often linked to detrimental effects on human health. Here, I show that supplementation of botanical extracts from Artemisia scoparia (SCO), dramatically increases animal lifespan. Mechanistically, this lifespan extension is dependent on AMPK-DAF-16 signaling via inhibition of the insulin pathway. In SCO-fed worms, longer lifespan was accompanied by higher fat storage and improved resiliency to age-related physiological stress. Notably, DAF-16, the master regulator of longevity, activated the fatty acid desaturation processes, which promoted the accumulation of …

Ion Selective And Water Resistant Cellulose Nanofiber/Mxene Membrane Enabled Cycling Zn Anode At High Currents, Wangwang Xu, Xiaobin Liao, Weina Xu, Kangning Zhao, Guang Yao, Qinglin Wu

Faculty Publications

Aqueous rechargeable zinc ion batteries (ZIBs) are regarded as a promising candidates for next-generation energy storage devices but strongly hindered by the limited utilization of the zinc metal anode (below 5%) due to the active water/anion corrosion. Herein, an ion selective and water-resistant cellulose nanofiber (CNF)/MXene composite membrane has been developed through molecular sieving to restrict active water and anions from the electrode/electrolyte interface through dehydration of zinc ions, avoiding the water/anion-induced corrosion/decomposition. In this way, the CNF/MXene@Zn anode exhibits significantly enhanced coulombic efficiency (99.5 % at 10 mA cm-2) and low voltage hysteresis. Moreover, coated with CNF/MXene composite membrane, …

A Critique Of Aristotle: Countervoluntary Action And Moral Injury, Melissa Altsman

LSU Master's Theses

“A Critique of Aristotle: Countervoluntary Action and Moral Injury,” is a critique of Aristotle’s view that countervoluntary action does not affect character. I argue that a countervoluntary action can affect character when said action leads to a moral injury. Throughout this critique I use military experiences of moral injury to bolster my argument. This critique focuses on Aristotle’s Nicomachean Ethics, and is directed at his Nicomachean Ethics specifically. The upshot of my critique is to not only argue that countervoluntary action affects character, but to spotlight specifically why it is character affecting. Essentially, my aim is to call attention …

Optimal Control Problems For Stochastic Processes With Absorbing Regime, Yaacov Kopeliovich

Journal of Stochastic Analysis

No abstract provided.

Development Of Novel Electrodes And Electrolytes For Safer Aqueous Ammonium Ion Batteries With Enhanced Performance., Shelton Farai Kuchena

LSU Doctoral Dissertations

The Lithium-ion battery (LIBs) system has dominated the battery market because of its superior energy and power density. Problems related to LIBs such as safety, scarcity of cobalt and lithium have led researchers to explore alternative battery systems. NH₄⁺ ion is a nonmetal charge carrier with lower molar mass (18 mol g^-1) and smaller hydrated ionic size (3.31 Å) which results in excellent electrochemical properties. Furthermore, NH₄⁺ ion has a tetrahedral structure that has no preferred orientation as compared to spherical metal ions giving a different intercalation chemistry based on hydrogen bonding. These properties …

Calibration And Use Of S3f Sensor For Normal And Shear Stress Measurements In Soil, Hussein Alqrinawi

LSU Master's Theses

Innovative sensors can provide new capabilities to monitor and understand the behavior of soil, rock, and geo-structures and help geotechnical engineers make informed decisions about the construction and maintenance of geo-structures. This study introduced, calibrated, and validated one such sensor, the Surface Stress Sensitive Film (S3F) point sensor, for both normal and shear stress measurements in soil along the soil-structure interface. The measurements of S3F sensor rely on the deformation of an elastic film that is monitored by a floating element embedded in the elastic film. This sensor provides measurements of the 3D deformation of the film which are converted …

Understanding The Influence Of Colorism On The Dating Preferences Of Black Undergraduate Students At Predominantly White Institutions, Odessa Foster

LSU Master's Theses

This study examined the effects of colorism on emerging Black undergraduate college students and how it influences their dating preferences while attending a Predominantly White Institution. The participants were 18-24 years old and self-identified as Black women attending a PWI. A secondary analysis was conducted. The findings of this study revealed that family can influence emerging Black adults dating preferences as they are likely to have the same preference as their family. There is a significantly positive relationship between family preference and dating preferences. This study also examined the correlation between media/social media and dating preferences. As there were positive …

Seasonal Seepage Fluid Flow And Pressure Detection Beneath Flood Protection Levees In The Lower Mississippi River Valley Using Non-Invasive Geophysical Methods, Daniel Locci

LSU Doctoral Dissertations

This study explores the use of shear-wave seismic reflection and electrical resistivity techniques to complement our understanding of seepage pore pressure variations and soil type estimation beneath earthen levees in the Mississippi River floodplain. The seasonal variations of water level in the river create changes in pore pressure in the adjacent aquifer, which can be detected using time-lapse shear-wave velocity analysis. The seismic reflection patterns during these pressure variations show changes in velocity that can be translated into changes in effective pressure, allowing us to distinguish between confined and leaky aquifers.

In addition, the integration of geophysical methods such as …

Cell-Specific Role Of Il4rα Signaling In Allergic Asthma, Ishita Choudhary

LSU Doctoral Dissertations

IL-4 and IL-13 play a critical role in allergic asthma pathogenesis via their common receptor, i.e., interleukin 4 receptor alpha (IL4Rα). However, the cell type-specific role of IL4Rα-mediated signaling in allergic asthma has remained unclear. We hypothesized that the role of IL4Rα signaling in allergic asthma is cell-type specific. To test our hypothesis, we challenged myeloid cell-specific IL4Rα-deficient (LysMcre^+/+/IL4Rα^fl/fl), myeloid cell-specific IL4Rα-sufficient (LysMcre^+/+/IL4Rα^wt/wt), airway epithelial cell-specific IL4Rα-deficient (CCSP-Cre⁺/IL4Rα^fl/fl), and airway epithelial cell-specific IL4Rα-sufficient (CCSP-Cre^-/IL4Rα^fl/fl) mice with either mixed allergens (MA) or normal saline three …

In Knowledge We Trust(Ed): A Case Study In Abolition Theatre, Misty Dawn Saribal

LSU Doctoral Dissertations

This dissertation argues for performance art’s role(s) in growing abolition on higher education campuses. After defining abolition’s intersections with higher education, and discussing why performance is often diminished and overlooked, I examine a university abolitionist performance I co-directed that highlighted prison labor on our university’s campus titled ‘In Knowledge We Trusted: Red Tape, White Institutions, and Blue Students.’ A rationale for abolition performance and an abolition performance praxis is detailed with attention to avoiding the pitfalls of authenticity policing in prison abolition and genre policing in abolitionist art. Conclusions about how the performance contributed to and embodied abolition politics and …

Rapid Intensification As A Crucial Hurricane Hazard: Educating And Empowering Young Stakeholders Affected By Hurricanes On The Gulf Coast, Kathleen M. Benedetto

LSU Doctoral Dissertations

In recent decades, the scientific ability to project tropical cyclone (TC) intensities and tracks has improved. Hurricanes undergoing the process of rapid intensification (RI) have created new barriers in formulating predictions of TC paths and peak velocities. Current research suggests the warming climate may produce more intense TCs with a higher probability of undergoing RI during their life cycle. The increased likelihood of rapidly intensifying TCs necessitates the development of an RI climatology spanning the current North Atlantic record. A time series count analysis suggests a significant increasing trend of RI events in the Atlantic basin by 29.1% (17%–45%) from …