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Droplet-Based Fuel Property Measurements, Wanjun Dang Dec 2021

Droplet-Based Fuel Property Measurements, Wanjun Dang

LSU Doctoral Dissertations

Ongoing work to find renewable biofuels to function as drop-in replacements or blending components with gasoline has identified a large number of fuel candidates. Given the vast number of potential biomass-derived fuel molecules and limited sample sizes, screening tools are required to down-select candidate fuels having desired physical properties to ensure good engine performance. This work investigates approaches for rapid screening of candidate fuels using micro-liter sample sizes targeting four properties -- surface tension, viscosity, heat of vaporization (HOV), and vapor pressure. Measurement techniques for fuel properties are developed based on unit phenomena for liquid fuel droplets including droplet oscillation …


Functional Structure Of Biomacromolecules In Plant Biomass Using Solid-State Nmr And Dynamic Nuclear Polarization, Alex Kipchirchir Kirui Dec 2021

Functional Structure Of Biomacromolecules In Plant Biomass Using Solid-State Nmr And Dynamic Nuclear Polarization, Alex Kipchirchir Kirui

LSU Doctoral Dissertations

This dissertation summarizes the recent findings on complex biomacromolecules in cell wall of plants and fungi which perform important roles in cell recognition, structural build up, and energy storage. Because of the technical difficulty in characterizing these biomacromolecules, which are often polymorphic and disordered in structure, the functional structure of these biomacromolecules remains elusive. In this dissertation, I present two solid-state nuclear magnetic resonance (ssNMR) and dynamic nuclear polarization (DNP) studies of carbohydrate-rich biosystems: the energy-rich plant biomass and disease-relevant, pathogenic fungi.

First, we have investigated the secondary cell wall of plant biomass which is a carbohydrate-rich biosystem using solid …


Limits On Parameter Estimation Of Quantum Channels, Vishal Katariya Dec 2021

Limits On Parameter Estimation Of Quantum Channels, Vishal Katariya

LSU Doctoral Dissertations

The aim of this thesis is to develop a theoretical framework to study parameter estimation of quantum channels. We begin by describing the classical task of parameter estimation that we build upon. In its most basic form, parameter estimation is the task of obtaining an estimate of an unknown parameter from some experimental data. This experimental data can be seen as a number of samples of a parameterized probability distribution. In general, the goal of such a task is to obtain an estimate of the unknown parameter while minimizing its error.

We study the task of estimating unknown parameters which …


Reaction Pathways Of Molecular Growth For Bay-Region Methyl-Substituted Polycyclic Aromatic Hydrocarbons During Supercritical Pyrolysis Of N-Decane, Venkata Sai Krishna Karthik Vutukuru Nov 2021

Reaction Pathways Of Molecular Growth For Bay-Region Methyl-Substituted Polycyclic Aromatic Hydrocarbons During Supercritical Pyrolysis Of N-Decane, Venkata Sai Krishna Karthik Vutukuru

LSU Doctoral Dissertations

Prior to its combustion, fuel for future-highspeed aircraft will experience supercritical conditions, causing the fuel to undergo pyrolytic reactions that lead to the formation of polycyclic aromatic hydrocarbons (PAH), precursors to fuel-line solids that hinder aircraft’s safe operation. Therefore, understanding the formation pathways of PAH under supercritical conditions is important to preventing formation of these solids.

Previous work from our group has shown that n-alkanes are particularly problematic regarding solids formation and that the model fuel n-decane produces an abundance of aliphatics and one- to nine-ring aromatics—many of which are methyl-substituted. Some of these methyl-substituted PAH have their …


The Rural Road: A Phenomenological Study Exploring Advanced Placement Coursework And College Readiness In Louisiana, Willie Adelaide Louviere Nov 2021

The Rural Road: A Phenomenological Study Exploring Advanced Placement Coursework And College Readiness In Louisiana, Willie Adelaide Louviere

LSU Doctoral Dissertations

Rigorous coursework is one of the necessary staples in establishing college readiness. Rural districts are much less likely to offer advanced coursework opportunities to students. The purpose of this qualitative study is to examine the equitable access to advanced coursework opportunities (Advanced Placement) provided to rural students (in-person and distance learning) in public rural high schools in Louisiana. Access to advanced coursework (Advanced Placement, Dual Enrollment, etc.) serves as an indicator of college readiness; however, a substantial gap exists in providing the programs to underserved student populations. Rural students face significant barriers that can hinder their ability to thrive on …


The Origin And The Evolution Of The Double Bass, Patrick James Lavergne Nov 2021

The Origin And The Evolution Of The Double Bass, Patrick James Lavergne

LSU Doctoral Dissertations

This dissertation will trace the double bass from the 16th century to the 21st century. The double bass is the largest and lowest pitched member of the string family. The members of the string family are the violin, viola, cello, and the double bass. The pitch of the double bass sounds one octave lower than the written pitch. The double bass is sometimes called the contrabass, string bass, upright bass, or bass fiddle. It is used in different genres of music such as classical, jazz, blues, bluegrass, country & western, and even rock.


Improving The Deployment Of Insecticidal Seed Treatments In Louisiana Rice In Accordance With Integrated Pest Management, Megan Marie Mulcahy Nov 2021

Improving The Deployment Of Insecticidal Seed Treatments In Louisiana Rice In Accordance With Integrated Pest Management, Megan Marie Mulcahy

LSU Doctoral Dissertations

Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), is the most destructive insect pest of rice in the United States. Lissorhoptrus oryzophilus larvae feed on rice roots, reducing yields by up to 25 %. Lepidopteran stem borers, in the family Crambidae, are also economically important pests of rice in Louisiana.

Currently, insecticidal seed treatments are used throughout the U.S. Mid-south rice industry to prophylactically control L. oryzophilus. Chlorantraniliprole seed treatments are also effective against stem borers. Thus, insecticidal seed treatments are used on >80 % of Louisiana rice acreage. Although seed treatments reduce damage inflicted by these pests, they are applied preventatively …


Asynchronous, Distributed Optical Mutual Exclusion And Applications, Ahmed Bahaael Mansour Nov 2021

Asynchronous, Distributed Optical Mutual Exclusion And Applications, Ahmed Bahaael Mansour

LSU Doctoral Dissertations

Silicon photonics have drawn much recent interest in the setting of intra-chip andmodule communication. In this dissertation, we address a fundamental computationalproblem, mutual exclusion, in the setting of optical interconnects. As a main result, wepropose an optical network and an algorithm for it to distribute a token (shared resource)mutually exclusively among a set ofnprocessing elements. Following a request, the tokenis granted in constant amortized time andO(n) worst case time; this assumes constantpropagation time for light within the chip. Additionally, the distribution of tokens is fair,ensuring that no token request is denied more thann−1 times in succession; this is thebest possible. …


An Investigation Examining The Closing Of The Achievement Gap In Louisiana With The Ngss, George Cage Nov 2021

An Investigation Examining The Closing Of The Achievement Gap In Louisiana With The Ngss, George Cage

LSU Doctoral Dissertations

The purpose of this study was to investigate the Next Generation Science Standards (NGSS) and its implications of being a curricular and pedagogical intervention in terms of narrowing the achievement gap in science education for Children of Color. In using the explanatory mixed methods design, standardized test data and one-on-one interviews were examined to assess the effectiveness and impact of the NGSS’ implementation in the state of Louisiana. This study utilized student performance results from the LEAP 2025 to conduct a statistical analysis that measured trends in performance by Children of Color, specifically Black students, before and after the implementation …


Non-Adiabatic Excited State Molecular Dynamics Using Ehrenfest And Modulated X-Ray Absorption In Titania, Alexander Matthew Meyer Nov 2021

Non-Adiabatic Excited State Molecular Dynamics Using Ehrenfest And Modulated X-Ray Absorption In Titania, Alexander Matthew Meyer

LSU Doctoral Dissertations

This dissertation contains two separate sections aside from an introduction (Chapter 1): theory and methods (Chapter 2), time dependent density functional theory with Ehrenfest for excited state lifetimes in materials (Chapter 3), and simulated field modulated X-ray absorption in titania (Chapter 4).

Excited state lifetime in insulators and semiconductors can be difficult to compute using quantum chemistry due to their dense excited states. Non-radiative decay in these materials requires the use of non-adiabatic effects to dissipate energy through the means of electron-nuclear coupling such as coherent phonon generation. One method of approaching this challenge in these materials is using Ehrenfest …


Numerical Investigation Of The Impact Of Distortion On The Hydrodynamics In The Lower Mississippi River Physical Model (Lmrpm), Ali Heidarizhaleh Nov 2021

Numerical Investigation Of The Impact Of Distortion On The Hydrodynamics In The Lower Mississippi River Physical Model (Lmrpm), Ali Heidarizhaleh

LSU Doctoral Dissertations

The Lower Mississippi River Physical Model (LMRPM) is a distorted-scale, 1:6000 horizontal and 1:400 vertical, movable-bed model that is being used to complement ongoing numerical and field studies directed at studying how non-cohesive sediment transport will be impacted by future changes in relative sea level rise and river discharges, as well various management strategies, such as river sediment diversions, in the lower ~190 miles of the Mississippi River The LMRPM was designed using Froude number (Fr) similarity between the prototype and the model, while the flow Reynolds number is relaxed, but determined to be high enough to ensure rough turbulent …


Congruences Between Coefficients Of A Class Of Eta-Quotients And Their Applications To Combinatorics, Shashika Petta Mestrige Nov 2021

Congruences Between Coefficients Of A Class Of Eta-Quotients And Their Applications To Combinatorics, Shashika Petta Mestrige

LSU Doctoral Dissertations

Ramanujan in $1920$s discovered remarkable congruence properties of the partition function $p(n)$. Later, Watson and Atkin proved these congruences using the theory of modular forms. Atkin, Gordon, and Hughes extended these works to $k$-colored partition functions. In $2010$, Folsom-Kent-Ono and Boylan-Webb proved the congruences of $p(n)$ by studying a $\ell$-adic module associated with a certain sequence of modular functions which are related to $p(n)$.

Primary goal of this thesis is to generalize the work of Atkin, Gordon, Hughes, Folsom-Kent-Ono, and Boylan-Webb about the partition function to a larger class of partition functions. For this purpose we study a closely related …


Application Of Gas-Assisted Gravity Drainage (Gagd) Process For Enhancing Recovery From Unconventional Resources, Muzher Al Musabeh Nov 2021

Application Of Gas-Assisted Gravity Drainage (Gagd) Process For Enhancing Recovery From Unconventional Resources, Muzher Al Musabeh

LSU Doctoral Dissertations

The oil recovery with hydraulic fracturing has played an important role in hydrocarbon production and energy support last decade from unconventional resources. Characteristically, the significant production decline and low recovery factors from these reservoirs triggered the need for new EOR techniques to compensate for the decline and help sustain the production. In this study, an experimental investigation of the Gas-Assisted Gravity Drainage (GAGD) process in the presence of fractures as EOR process was conducted using Nitrogen (N2) and Carbon Dioxide (CO2) in Berea Sandstone (BSS) and Tuscaloosa Marine Shale (TMS). Core flooding and EOR experiments were used to determine the …


The Orlando International Fringe Festival: An Historical And Administrative Overview, Brook Akya Hanemann Nov 2021

The Orlando International Fringe Festival: An Historical And Administrative Overview, Brook Akya Hanemann

LSU Doctoral Dissertations

This dissertation marks the first historical and administrative overview of the Orlando International Fringe Festival. The Orlando International Fringe Festival (OIFF) is America's oldest still-operating fringe theatre festival. This two-week performing arts and immersive cultural event features uncensored, unjuried, accessible, and inclusive performances on indoor and outdoor stages. The Festival subverts traditional commercial theatre models by giving 100% of ticket proceeds back to its artists. Originally held in Downtown Orlando, it now resides at the Loch Haven Cultural Complex of Orlando where it overcame struggles common to arts organizations such as the beer truck scenario, a sustainability issue linking an …


Time And Tide: Sixteenth-Century Expressions Of Temporality In The Writings Of Richard Hakluyt, Jennifer Hope Tellman Nov 2021

Time And Tide: Sixteenth-Century Expressions Of Temporality In The Writings Of Richard Hakluyt, Jennifer Hope Tellman

LSU Doctoral Dissertations

Richard Hakluyt the Younger (c. 1553-1616) was the most famous English promoter of overseas expansion of his age and in English history. His most renowned publication, Principal Navigations (1598-1600), a massive three-volume series, detailed English exploration, expansion, and trade history. With a focus on inciting the English to act in order to achieve their Providential Empire, Hakluyt’s works carry in them the expressions of time and temporality permeating the late-1500s. In a period of history where new learning, discoveries, and technologies began to transform life, time was called into question. Concerns about how the perception and acceleration of time and …


System Design And Optimization For Efficient Flash-Based Caching In Data Centers, Jian Liu Nov 2021

System Design And Optimization For Efficient Flash-Based Caching In Data Centers, Jian Liu

LSU Doctoral Dissertations

Modern data centers are the backbone of today’s Internet-based services and applications. With the explosive growth of the Internet data and a wider range of data-intensive applications being deployed, it is increasingly challenging for data centers to satisfy the ever-increasing demand for high-quality data services. To relieve the heavy burden on data center systems and accelerate data processing, a popular cost-efficient solution is to deploy high-speed, large-capacity flash-based cache systems. However, we are facing multiple critical challenges from device hardware, systems, to application workloads. In this dissertation, we focus on designing highly efficient caching solutions to cope with the explosive …


Interface-Induced Lattice Structure And Magnetism In Ultrathin Transition Metal Oxide Trilayers, David Howe Nov 2021

Interface-Induced Lattice Structure And Magnetism In Ultrathin Transition Metal Oxide Trilayers, David Howe

LSU Doctoral Dissertations

The study of magnetism has been a rich playground in condensed matter physics due to the multiple mechanisms capable of producing the effect and its relationship to multiple characteristics of a material. Transition metal oxides (TMOs) have been of particular interest for ongoing research into magnetic phenomenon due to the abundance of interesting physical phenomena found in member systems such as colossal magnetoresistance, skyrmion formation, and interface-driven 2D electron gases. Thin films introduce an additional thickness-dependent element, where reduction below a critical thickness eliminates the magnetic coherence of a system and FM order is lost. The atomic structure of these …


Investigation Of Arabidopsis Extremophyte Relatives, Schrenkiella Parvula And Eutrema Salsugineum Reveals Different Roads Leading To Salt Stress Tolerance, Kieu-Nga Thi Tran Nov 2021

Investigation Of Arabidopsis Extremophyte Relatives, Schrenkiella Parvula And Eutrema Salsugineum Reveals Different Roads Leading To Salt Stress Tolerance, Kieu-Nga Thi Tran

LSU Doctoral Dissertations

How plants adapt to salt stress has been a central question in plant biology for decades. Yet we have not been able to fully understand the molecular networks and genetic mechanisms underlying this complex trait. Most of the genetic work on salinity stress has focused on understanding salt stress responses in the leading, yet a salt-sensitive model Arabidopsis thaliana. With the recent availability of genomes for wild-relatives of A. thaliana, we can now investigate how naturally salt adapted plants may have evolved modified or novel molecular networks to adapt to salt stress. Therefore, my research utilizes a comparative …


Insights Into Abscisic Acid And Phosphatidic Acid Signal Transduction Dynamics In Arabidopsis Thaliana, Ruth Wanjiru Ndathe Nov 2021

Insights Into Abscisic Acid And Phosphatidic Acid Signal Transduction Dynamics In Arabidopsis Thaliana, Ruth Wanjiru Ndathe

LSU Doctoral Dissertations

Abscisic acid (ABA) is a plant hormone that triggers a signaling transduction in response to drought, salinity, and cold. The core components in the ABA signaling pathway that lead to downstream ABA responses have been identified.

Phosphatidic acid (PA) is a membrane phospholipid that is involved in the signaling pathway for ABA-induced stomatal closure. We tested whether PA is involved in the signaling pathway for ABA-induced gene expression as well, using model plant Arabidopsis thaliana. We selected the RD29A gene which is a canonical drought gene that is induced by ABA. We found that PA is not involved in …


African American English-Speaking Children's Judgments Of Grammaticality: Effects Of Clinical Status And Grammatical Structures, Lori Elizabeth Vaughn Nov 2021

African American English-Speaking Children's Judgments Of Grammaticality: Effects Of Clinical Status And Grammatical Structures, Lori Elizabeth Vaughn

LSU Doctoral Dissertations

African American English (AAE)-speaking children’s ability to judge the grammaticality of sentences was evaluated by their clinical status and grammatical structure. The study originated from a need to understand more about the tense and agreement systems of AAE speakers with specific language impairment (SLI) relative to their typically developing (TD) AAE-speaking peers. Tense and agreement forms are typically excluded from the assessment and treatment of children who speak AAE in fear of misinterpreting a dialect difference as a language disorder. As a result, limited information exists about the tense and agreement systems of AAE-speaking children.

The data were archival and …


Genetic Structuring And Community Assembly In Neotropical Birds, Oscar Johnson Nov 2021

Genetic Structuring And Community Assembly In Neotropical Birds, Oscar Johnson

LSU Doctoral Dissertations

The factors that influence how species form is of fundamental interest to biology. Under the framework of the speciation cycle, the process begins by population subdivision creating structured populations that then diverge until two new species form. Following speciation, however, continued divergence is necessary for these new species to be able to coexist without adverse interactions, known as the transition to secondary sympatry. At this point the speciation cycle is complete and the process can begin anew. Many of the factors influencing these processes remain poorly understood. Here, I explore the factors that influence speciation and community assembly in Neotropical …


Casting A Critical Lens On Global Development: A Multimethod Investigation Of The Masculine Hegemonic Forces That Marginalize Women In Agriculture, Morgan Alyse Richardson Gilley Nov 2021

Casting A Critical Lens On Global Development: A Multimethod Investigation Of The Masculine Hegemonic Forces That Marginalize Women In Agriculture, Morgan Alyse Richardson Gilley

LSU Doctoral Dissertations

A critical link between gender equality and agricultural development has been established in the literature. However, disparities between genders have persisted in many areas of the developing world. One strategy that has been used to reduce gender inequalities has been educational outreach opportunities through agricultural extension, which has provided women a critical pathway to empowerment. Despite this, a lack of knowledge on the experiences of women in agriculture throughout Southeast Asia has served as a barrier to the advancement of such work. This investigation sought to better understand the issues facing this region’s fight to attain gender equality. To achieve …


The Confederate Stories Of America: The Short-Story Cycle And The Representation Of The American South, Ikuko Takeda Nov 2021

The Confederate Stories Of America: The Short-Story Cycle And The Representation Of The American South, Ikuko Takeda

LSU Doctoral Dissertations

My dissertation examines the ways in which the short-story cycle has provided a unique generic framework for representing and investigating the complex interplay of contending forces that constitute what we think of as the American South. Often confused with a collection of disparate short stories or a novel, the short-story cycle is a collection of short stories in which each story is independent, but simultaneously interrelated to one another. Although the South has produced a number of short-story cycles or linked story collections, scholars have not paid much attention to the connection between the genre/form and the region. I consider, …


Impact Of Software Changes On User Experience, Job Michael Champagne Nov 2021

Impact Of Software Changes On User Experience, Job Michael Champagne

LSU Doctoral Dissertations

Software changes are performed frequently to allow cutting edge features to be delivered to users in a timely manner and to assuage the ever increasing security vulnerabilities found in software. These changes, while necessary, can leave users dissatisfied with software that they use. Security patches can slow down computer performance, and extensive user interface changes can leave users dissatisfied. This research presents a methodology for identifying which software changes have high potential to cause user dissatisfaction. As a part of the methodology, we use natural language processing to analyze the software or system requirements business rule text to determine which …


Genome-Wide Analysis Of Peg3 Downstream Genes, Subash Ghimire Nov 2021

Genome-Wide Analysis Of Peg3 Downstream Genes, Subash Ghimire

LSU Doctoral Dissertations

Paternally expressed gene 3 (Peg3) is an imprinted gene encoding a DNA-binding protein that is a predicted transcriptional repressor. The two studies presented here demonstrate the repressive functions of PEG3 in regulating different cellular processes and pathways, which were observed by analyzing the ChIP-seq results systematically using both bioinformatics tools and manual inspection of significant peaks. In the first part of the work, genome-wide features of ChIP-seq peaks were characterized and the potential de novo binding motif was reevaluated. Results suggested the transcriptional repressor role of PEG3 by binding to the conserved sequence motif of the target genes. …


The Influence Of Participation In Gambling Activities On The Personal Lives Of Gamblers As Perceived By Female Gamblers In Louisiana, Carondalette Turner Nov 2021

The Influence Of Participation In Gambling Activities On The Personal Lives Of Gamblers As Perceived By Female Gamblers In Louisiana, Carondalette Turner

LSU Doctoral Dissertations

Historically, gambling has been a source of many ills within many cultures throughout the United States. During the last five years, there has been a precipitous surge in the accessibility of legalized gambling. Few studies have methodically surveyed the relationships between extent of gambling behavior and the consequences of gambling that may occur. The primary purpose of this study was to determine the influence of selected personal, and perceptual demographic characteristics on the extent of gambling behavior exhibited by female residents of Baton Rouge, Louisiana.

This study used a survey design with instrument distributed by hand at selected community organizations. …


Investigating Plant Tolerance For The Management Of Insect Pests In Rice, James Michael Villegas Oct 2021

Investigating Plant Tolerance For The Management Of Insect Pests In Rice, James Michael Villegas

LSU Doctoral Dissertations

The rice water weevil, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), is the most destructive and widespread insect pest of rice (Oryza sativa L., Poaceae) in the USA. This insect poses a global threat to rice production, having invaded rice-producing regions of Asia and Europe. Moreover, lepidopteran stemborers, particularly the invasive Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), are increasingly becoming problematic in Louisiana rice. Although insecticidal seed treatments have been widely used against weevils and stemborers, alternative management strategies are needed. Plants possess defense-related traits that both reduce injury from herbivores (resistance) and the amount of yield loss per …


Floodplain Forests Vegetation Dynamics Driven By Water Deficits Across Scales, Nga Thanh Nguyen Oct 2021

Floodplain Forests Vegetation Dynamics Driven By Water Deficits Across Scales, Nga Thanh Nguyen

LSU Doctoral Dissertations

Restoration of floodplain ecosystems relies on identifying the most crucial hydrologic process which has been altered by human and climate. Flooding is a well-known dominant hydrologic process for floodplain ecosystems, but surprisingly little is known about drought's role in structuring ecosystems. In addition, several issues remained uncertain, such as the nature of drought within floodplains and the sensitivity of floodplain species-specific growth to climate. These gaps of understanding have in common in missing observations of mechanistic pathways of vegetation response to water deficits at multiple scales in time and space.Generally, this research contributed to floodplain management by expanding our understanding …


Connecting And Communicating: The Activation Of Middle School Parents As Learning Coaches For Ela Classrooms In Online Charter Schools, Lillie Connor-Flores Oct 2021

Connecting And Communicating: The Activation Of Middle School Parents As Learning Coaches For Ela Classrooms In Online Charter Schools, Lillie Connor-Flores

LSU Doctoral Dissertations

In recent years, K-12 online charter schools have seen increased enrollment as parents and guardians seek alternate options for educating their children. Online schools provide opportunities for flexibility, individualization, and continuous learning when in-person learning is not available. However, research on K-12 online schooling is currently minimal despite enrollment. Further, little to no research explores middle school online students or delves into the stakeholders who support students. Some online schools have employed a Learning coach—an adult assigned to work with a student at home. Learning coaches can be an asset for engaging learning. The researcher asks the following questions: How …


Classifying Soft X-Ray Objects In The Galactic Bulge, Joshua D. Wetuski Oct 2021

Classifying Soft X-Ray Objects In The Galactic Bulge, Joshua D. Wetuski

LSU Doctoral Dissertations

The Galactic Bulge Survey (GBS) is a broad and shallow X-ray survey designed to detect quiescent X-ray binary systems in the direction of the Milky Way bulge, which include objects such as low-mass X-ray binaries, cataclysmic variables, and symbiotic binaries. LMXBs can provide constraints to the neutron star equation of state and symbiotic systems and are likely progenitors of double white dwarf systems which are themselves candidate progenitors to type Ia supernova. We seek to improve identification and classification of optical counterparts to GBS in several ways. By improving upon the original GBS, an updated catalog was created to help …