Digital Commons Network^™

Molybdenum Alkylidyne Complexes With Phenoxide Ligands For Alkyne Metathesis, Marvin L. Stewart Jr

LSU Doctoral Dissertations

Abstract

Alkyne metathesis is a powerful synthetic tool, which provides easy access to complex organic molecules in a single-step. It is a dynamic covalent reaction that scrambles alkynes, carbon-carbon triple bonds (C≡C). Molybdenum- or tungsten-alkylidyne (Mo≡C, W≡C) complexes are typically used as catalyst to cleave and reform alkyne bonds. Our goal has been to gain a deeper understanding of the intrinsic differences between functional ligands by the development of novel phenoxide ligands.

In chapter 2 we explore the detailed synthesis of novel phenoxide podand ligands in an effort to identify their mo-alkylidyne complexes. We were able to synthesize a variety …

The Lowest Discriminant Ideal Of Cayley-Hamilton Hopf Algebras, Zhongkai Mi

LSU Doctoral Dissertations

Discriminant ideals are defined for an algebra R with central subalgebra C and trace tr : R → C. They are indexed by positive integers and more general than discriminants. Usually R is required to be a finite module over C. Unlike the abundace of work on discriminants, there is hardly any literature on discriminant ideals. The levels of discriminant ideals relate to the sums of squares of dimensions of irreducible modules over maximal ideals of C containing these discriminant ideals. We study the lowest level when R is a Cayley-Hamilton Hopf algebra, i.e. C is also a Hopf subalgebra, …

Ammonium Chemotaxis In Chlamydomonas Reinhardtii, Gabela Nelson

LSU Doctoral Dissertations

Analysis of ammonium chemotaxis in Chlamydomonas reinhardtii is largely hindered, compared to that of phototaxis, despite equal importance on flagellated microalgal physiology. A major contribution of this shortfall is the lack of proper assay method. We developed a simple Petri dish assay method in which light is homogenously exposed while patterns of the cellular migration are tracked with a function of time. Using the method, new findings were revealed. First, this research presented that a strain lacking the eyespot organelle required for light gradient-sensing exhibits similar chemotactic behavior compared to a wild-type strain, suggesting Chlamydomonas sense an ammonium gradient not …

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, …

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 …

A Study Of Selected Vocal Works By Shande Ding: The Mysterious Sound Of Flute And Poems On Western Yunnan, Chuyan Luo

LSU Doctoral Dissertations

This study aims to delve into and interpret “The Mysterious Sound of Flute” and “Poems on Western Yunnan” from a singer’s perspective while also providing guidance and recommendations for other performers. The research encompasses the history of Chinese art songs, a biography of Shande Ding, and an introduction to his compositional style. A comprehensive examination of each song includes background information, song analysis, translation, a Chinese lyric diction guide, and performance suggestions.

Art songs constitute a significant genre in music composition, and Chinese art songs have yielded numerous outstanding composers and captivating works over the years. Among these composers, Shande …

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.

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 …

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 …

“Redención”: Testimonios Of Latinas Who Chose To Leave The Higher Education Industry, Delia P. Madrid-Nothdurft

LSU Doctoral Dissertations

Using the methodological framework of testimonio, this study was an exploration of the experiences of former higher education professionals who identify as women in the Latinx community. Grounded in Latino Critical Theory (LatCrit) and Critical Race Feminism (CRF), this research aims to highlight the narratives of Latina professionals who have separated from the higher education sector. The study is informed by the conceptual framework of Chicana feminist perspective, which contextualizes the analysis of these experiences within a socio-cultural context. Using semi-structured interviews, participants shared their testimonios, providing rich accounts of their journeys and challenges within higher education. Through thematic …

Introducing Chinese Folk Songs Through Arrangements For Trombone & Piano And Chamber Music, Tianyu Xue

LSU Doctoral Dissertations

The scarcity of trombone in traditional Chinese music reflects the limited exposure and education for the trombone in China. Additionally, Chinese folk songs have minimal presence on the global stage. This project will bridge this gap by developing a series of trombone pieces that incorporate Chinese musical elements, explicitly focusing on elevating Chinese folk songs through trombone performance. This initiative offers an opportunity for trombonists worldwide to delve into the richness of Chinese folk music. The core of this work involves selecting Chinese folk songs that represent diverse historical contexts, regional characteristics, and emotional content and then arranging them for …

Unveiling The Idiomatic And Performance Inspirations: A Comparative Study Of The Red Violin Caprices By John Corigliano., Johan Alexander Pepper

LSU Doctoral Dissertations

John Corigliano's composition for "The Red Violin," a 1998 film by Don McKellar and François Girard, presents a multifaceted exploration of thematic material and performance challenges. This dissertation investigates Corigliano's creation of the "Red Violin" Caprices, examining their origins in the film's soundtrack and their transformation into solo works. Corigliano's intention to showcase the artistry of violinist Joshua Bell through these caprices underscores their technical and musical complexity. The Caprices, replete with references to the Baroque era and various virtuosic works, demand a high level of virtuosity from performers. Drawing on a sequence of seven chords and Anna’s Theme from …

Addition And Subtraction: Coral Reproduction And Disease In A Changing Ocean, Ashley Rossin

LSU Doctoral Dissertations

Marine diseases are changing the landscapes of coral reefs particularly throughout the Western Atlantic. Stony coral tissue loss disease (SCTLD) swept through this region impacting at least 22 stony coral species. White plague (WP) is a more ephemeral disease, but still has a significant impact on coral reef health and perseverance, especially under a changing ocean. While these impacts are seen on the reef-scale, we can zoom into the tissue-level to identify disease markers for both diseases and identify their differences. This has ramifications for disease intervention, as well as mitigation strategies. Despite continuous disease outbreaks, healthy corals persist and …

Subroups Of Coxeter Groups And Stallings Foldings, Jake A. Murphy

LSU Doctoral Dissertations

For each finitely generated subgroup of a Coxeter group, we define a cell complex called a completion. We show that these completions characterizes the index and normality of the subgroup. We construct a completion corresponding to the intersection of two subgroups and use this construction to characterize malnormality of subgroups of right-angled Coxeter groups. Finally, we show that if a completion of a subgroup is finite, then the subgroup is quasiconvex. Using this, we show that certain reflection subgroups of a Coxeter are quasiconvex.

Analytic Wavefront Sets Of Spherical Distributions On The De Sitter Space, Iswarya Sitiraju

LSU Doctoral Dissertations

In this work, we determine the wavefront set of certain eigendistributions of the Laplace-Beltrami operator on the de Sitter space. Let G′ = O_1,n(R) be the Lorentz group, and let H′ = O_1,n−1(R) ⊂ G′ be its subset. The de Sitter space dSⁿ is a one-sheeted hyperboloid in R^1,n isomorphic to G′/H′. A spherical distribution is an H′-invariant eigendistribution of the Laplace-Beltrami operator on dSⁿ. The space of spherical distributions with eigenvalue λ, denoted by D_λ^H'(dSⁿ), has dimension 2. We construct a basis for the space of …

The Modular Generalized Springer Correspondence For The Symplectic Group, Joseph Dorta

LSU Doctoral Dissertations

The Modular Generalized Springer Correspondence (MGSC), as developed by Achar, Juteau, Henderson, and Riche, stands as a significant extension of the early groundwork laid by Lusztig's Springer Correspondence in characteristic zero which provided crucial insights into the representation theory of finite groups of Lie type. Building upon Lusztig's work, a generalized version of the Springer Correspondence was later formulated to encompass broader contexts.

In the realm of modular representation theory, Juteau's efforts gave rise to the Modular Springer Correspondence, offering a framework to explore the interplay between algebraic geometry and representation theory in positive characteristic. Achar, Juteau, Henderson, and Riche …

Unavoidable Topological Minors Of Large Or Infinite 3-Connected Rooted Graphs, Phuc A. Nguyen

LSU Doctoral Dissertations

The goal of this thesis is to determine the unavoidable topological minors of large and infinite $ 3 $-connected rooted graphs, where a rooted graph is a graph $ G $ together with a specified subset $ X $ of $ V(G) $ or $ E(G) $. We have two results for finite graphs. First, every $ 3 $-connected finite graph $ G $ with a sufficiently large $ X \subseteq E(G) $ must contain a topological minor $ K_{3, n}, W_n $, or $ V_n $, using many edges of $ X $, where $ W_n $ is a …

Round Ii: Exploring The Experiences Of Black, First-Generation Graduate And Professional Students At Historically Black Colleges And Universities (Hbcus), Derrick D. Lathan

LSU Doctoral Dissertations

This phenomenological study explores the experiences of Black, first-generation (first-gen) students pursuing advanced degrees at historically Black colleges and universities (HBCUs), following the COVID-19 pandemic and racial justice movements like Black Lives Matter. Additionally, this study examines the present-day motivations to pursue advanced degrees, particularly the benefits of doing so at an HBCU. The main research question guiding this study is: What are the experiences of Black, first-gen graduate and professional students at historically Black colleges and universities (HBCUs)? The sub-questions are:

1. How do Black, first-gen graduate and professional students describe being a first-gen student?
2. What barriers and supports impact …

A Study Of Select Arias From Three Obscure Operas By Antonio Vivaldi: ‘Ottone In Villa,’ ‘Arsilda, Regina Di Ponto,’ And ‘Il Farnace’, Qinan Cai

LSU Doctoral Dissertations

This paper provides an analysis of select compositional tools found in chosen arias from Antonio Vivaldi’s lesser-known operas, Ottone in Villa RV 729, Arsilda, Regina di Ponto RV 700, and Farnace RV 711. It aims to illuminate Vivaldi’s exploration of human emotions and relationships through his music. The research focuses on select arias from each opera, emphasizing Vivaldi’s compositional style, use of sequential patterns, development of harmonic shifts in the music, and the inclusion of the Lombardic rhythm. In addition, commentary is included regarding the application of modal principles, and rhythmic speech patterns. The study also offers historical context and …

Sequencing Orchestral Repertoire For Collegiate Orchestras: Addressing The Educational Needs Of Students In Various Stages Of Development, Cheuk Nok Francis Ku

LSU Doctoral Dissertations

Sequencing is a fundamental aspect of music education, not only in individual instrumental teaching but also in large-ensemble instruction. Collegiate orchestras, like other educational ensembles, experience turnover of students each academic year, and face unique challenges in repertoire selection due to the diverse skill levels and experience of their members. This document presents a case study of the LSU Symphony Orchestra program spanning from 2021 to 2024, and complements a performance featuring works by Amy Beach, Ludwig van Beethoven, Joseph Haydn, and José Pablo Moncayo. The document also delved into the study of performance practice during the Classical period and …

Maria Rosa Ribas Monné: A Case Study, Rebeca Lemos Gonzalez

LSU Doctoral Dissertations

This dissertation explores the musical legacy of Catalan composer Maria Rosa Ribas Monné, emphasizing the influence of the Catalan context on her compositions and recognizing the contributions of Spanish women in music, particularly in cello music. Through an in-depth exploration of Maria Rosa's life, musical perspective, and analysis of her works "Faust", "Disperato,"and "Record d'una música," this study unveils pivotal insights into her artistic journey. Additionally, it includes a comprehensive catalogue of her compositions, providing a detailed overview of her musical output.

The dissertation begins by examining how M. Rosa Ribas' deep connection to Catalan culture, influenced by poet Màrius …

Modeling And Numerical Analysis Of The Cholesteric Landau-De Gennes Model, Andrew L. Hicks

LSU Doctoral Dissertations

This thesis gives an analysis of modeling and numerical issues in the Landau-de Gennes (LdG) model of nematic liquid crystals (LCs) with cholesteric effects. We derive various time-step restrictions for a (weighted) $L^2$ gradient flow scheme to be energy decreasing. Furthermore, we prove a mesh size restriction, for finite element discretizations, that is critical to avoid spurious numerical artifacts in discrete minimizers that is not well-known in the LC literature, particularly when simulating cholesteric LCs that exhibit ``twist''. Furthermore, we perform a computational exploration of the model and present several numerical simulations in 3-D, on both slab geometries and spherical …

Exploring The Spanish Pianistic Landscape: A Study On Salvador Brotons's Solo Piano Works, Angela P. Gonzalez Gimenez

LSU Doctoral Dissertations

This dissertation delves into the figure of Spanish composer Salvador Brotons, focusing on his solo piano works, particularly his Piano Sonata, Op. 124. Through performative and music theory analyses, it aims to deepen musicians' understanding of Brotons's compositional style, providing insights into his musical language and influences. Key questions addressed include Brotons's compositional style, influences in his music, and the necessary insights for effective performance. Brotons, a multifaceted musician, excels not only as a composer but also as an instrumentalist, conductor, and educator, enriching each role with his diverse expertise. The study concentrates on his piano compositions while acknowledging …

Mentorship Within Developmental Networks: A Phenomenological Study Of Black Women Tenured Associate Professors And Their Path Toward Full Professor, Jenifer F. Godfrey

LSU Doctoral Dissertations

The problem of inadequate representation of Black women in tenure track faculty positions is both pronounced and longstanding. With Black women making up less than 2% of full professors, this is particularly true at institutions categorized as R1 – Doctoral Universities – Very high research activity by The Carnegie Classification of Institutions of Higher Education. College faculty have long been the focus of scholarly research. However, studies focused on mentorship to be promoted to full professor for associate professors generally, and Black women associate professors specifically, are lacking. Using a conceptual framework that defined mentorship broadly as developmental networks and …

Prescribed Fire Effects On Microbial Communities And Functions In Managed Ecosystems, Viet Dao

LSU Doctoral Dissertations

Microbes (both fungi and bacteria) serve important ecosystem functional roles in nutrient cycling and decomposition, which affect ecosystem response following disturbances such as prescribed fire. A multitude of abiotic and biotic factors influence microbial community compositions, which then drive microbial ecosystem functions. The factors driving microbial communities further change due to fire disturbances and progression with time. Although prescribed fire is commonly used as a technique for ecosystem management, the effects of fire on microbial communities or their functions are simply understudied. Ecosystem management decisions tend to focus on plant and ecosystem post-fire responses. Thus, incorporation of fire effects on …

Problem-Solving In The Preparation Of Teachers For Agricultural Education: A Mixed Methods Study Investigating The Effect Of Metacognitive Awareness And Cognitive Ability On Students Enrolled In An Introductory Agricultural Mechanics Course, Whitney Figland

LSU Doctoral Dissertations

Cognitive and metacognitive ability have been identified as a critical factor that influences individuals to successfully problem-solve. However, recent research has indicated that students do not have the necessary 21st-century skills to be successful in the workplace. This issue has been confounded by the lack of school-based agricultural education (SBAE) teachers’ limited knowledge regarding effectively teaching decision-making skills and the use of teaching methods that promote problem-solving. Therefore, this study sought to understand the effect that cognitive and metacognitive ability had on the problem-solving of students who are enrolled in an Introduction to Agricultural Mechanics course at Louisiana State University. …

What Is Eai? A Short History Of The Style’S Evolution And Development Of Identifiable Characteristics, Dylan Burchett

LSU Doctoral Dissertations

EAI (Electro-Acoustic Improvisation) has long presented issues pertaining to its definition and practice. This is due to the wide range of acoustic and electronic sounds present in the style as well as the style’s stated adherence to improvisation. This stated adherence to improvisation and wide potential range of acoustic and electronic sounds seem to clash with EAI’s stylistic consistencies. Because the EAI style has been difficult to define, it has also been difficult to place historically within experimental music traditions. In order to clarify the definition, practice, and historical positioning of EAI and identify where the style’s boundary lines around …

Investigating Gulf Coast Aquifer System: Stratigraphy Reconstruction, Inverse Modeling, And Groundwater Stress Assessment, Shuo Yang

LSU Doctoral Dissertations

The Mississippi Embayment aquifer system (MEAS) and the Coastal Lowlands aquifer system (CLAS) provide substantial groundwater resources for human activities in the U.S. Gulf Coastal Plain. However, the overexploitation has led to groundwater depletion in the MEAS and the CLAS, threatening sustainable groundwater use. Such concern highlights the crucial need for an advanced understanding of stratigraphy and groundwater in these aquifer systems, which is essential for effective regional groundwater management. This dissertation presents a comprehensive investigation of MEAS and CLAS in the Louisiana and southwestern Mississippi region, encompassing three fundamental dimensions: stratigraphy reconstruction, groundwater modeling, and groundwater stress assessments. A …

In-Person, Hybrid, Or Remote: Exploring The Effectiveness Of Teacher Practices On Student Performance During The Covid-19 Pandemic, Ashley M. Segalla

LSU Doctoral Dissertations

Schools and universities had to make unexpected changes beginning in Spring 2020 because of the COVID-19 pandemic. In Spring 2021, one university in the southern region of the United States implemented hybrid teaching formats in College Algebra courses, where students attended half of the classes in-person, and the remaining half of classes were attended synchronously and remotely. The purpose of this mixed methods study was to determine if students’ attendance methods (virtual or in-person) impacted their academic performance in the course. Additionally, the study sought to determine how students and the instructor felt student performance was impacted by hybrid attendance. …