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Chemical And Biological Evaluation Of Antibiotic-Based Ionic Liquids And Gumbos Against Pathogenic Bacteria, Marsha Rae Cole

LSU Doctoral Dissertations

The research presented in this dissertation explores a novel pragmatic therapeutic approach for control, prevention, and treatment of infectious disease using Active-Pharmaceutical Ingredient-based Ionic Liquids (API-ILs) and Groups of Uniform Materials Based on Organic Salts (GUMBOS). Accordingly, several antiseptic- and antibiotic-based API-ILs and GUMBOS were synthesized and characterized using a combination of analytical and microbiological techniques. Overall, this research presents an advanced alternative to combination antibiotic therapy by using a novel group of ionic antimicrobial materials that have controlled pharmacokinetics, improved bioavailabilities, reduced toxicities, multi-modal properties, and potent antimicrobial spectrum of activity as a viable alternative to combating bacterial infections. …

Hypercube Diagrams For Knots, Links, And Knotted Tori, Ben Mccarty

LSU Doctoral Dissertations

For a knot K the cube number is a knot invariant defined to be the smallest n for which there is a cube diagram of size n for K. Examples of knots for which the cube number detects chirality are presented. There is also a Legendrian version of this invariant called the Legendrian cube number. We will show that the Legendrian cube number distinguishes the Legendrian left hand torus knots with maximal Thurston-Bennequin number and maximal rotation number from the Legendrian left hand torus knots with maximal Thurston-Bennequin number and minimal rotation number. Finally, there is a generalization of cube …

Entanglement, Uncertainty And Relativity In Fundamental Mechanics With An Application In Qkd, Christopher David Richardson

LSU Doctoral Dissertations

In this dissertation I will probe the innate uncertainty of quantum mechanics. After deriving the necessary tools I will tackle Popper's experiment, a long misunderstood thought experiment with recent experimental results. I will then discuss how uncertainty changes when making measurements from different relativistic reference frames and resolve some on the tension between quantum mechanics and relativity. Finally I utilize the practical aspect of quantum uncertainty and describe a practical quantum key distribution scheme.

Developing A Geospatial Protocol For Coral Epizootiology, Jennifer Anne Lentz

LSU Doctoral Dissertations

This dissertation explores how geographic information systems (GIS) and spatial statistics, specifically the techniques used to map, detect, and spatially analyze disease epidemics, could be used to advance our understanding of coral reef health. Given that different types of spatial analysis, as well as different parameter settings within each analysis, can produce noticeably different results, poor selection or improper use of a given technique would likely lead to inaccurate representations of the spatial distribution and false interpretations of the disease. For this reason, I performed a comprehensive review of the following types of exploratory spatial data analysis (ESDA): mapping and …

Total Synthesis Of A Virotoxin And Analogs For Conformational Studies, Benson Jumba Edagwa

LSU Doctoral Dissertations

This dissertation describes the first total synthesis of alloviroidin in trace amounts, along with that of three analogs containing L-proline (Pro), trans-3-hydroxyproline (3-Hyp) or cis-4-hydroxyproline (4-hyp) residue substituting for 2,3-trans-3,4-trans-dihydroxyproline in the natural product. We report herein an efficient strategy that provides a dipeptide containing a (2S,4S)-4,5-dihydroxyleucine (dihyLeu) residue, including a diastereoselective dihydroxylation. Nα-Carbobenzyloxy-(2S)-4,5-dehydroleucine was coupled with valine ethyl ester to give a dipeptide that was subjected to a Sharpless asymmetric dihydroxylation to introduce the diol. The relative configuration at C4 was assigned as S by X-ray crystallography after derivatization as an α-amino-γ-lactone hydrochloride salt. The preparation of the 2-(methylsulfonyl)tryptophan …

Dynamic Route Choice In Hurricane Evacuation, Meisam Akbarzadeh

LSU Doctoral Dissertations

In this research a framework is developed for modeling route choice in hurricane evacuation. Two behavioral hypotheses are evaluated which together with the route choice model, constitute the contributions of the research. The first hypothesis states that beside congestion, other variables such as familiarity with the route, availability of fuel and shelter, facility class, and length of route have an effect on an evacuees' route choice. The second hypothesis states that as time passes and storm conditions change, the impact each variable has on route choice changes. The logit structure was used for modeling the choice process and stated choice …

The Effects Of Spatial Confinement And Oxygen Stoichiometry On Complex Metal Oxides, Zhaoliang Liao

LSU Doctoral Dissertations

Complex metal oxides, such as transition-metal oxides, appearing with exotic properties and optimal functionalities, present formidable challenges in condensed matter physics, while at the same time, immense opportunities in materials science and engineering. The signature of these materials is the multitude of competing ground states that can be tuned or manipulated by doping, structural modification, strain induction, or the application of external stimulus, such as pressure, electric or magnetic fields, etc. The interest in these materials stems from the richness of their novel properties, the complexity of underlying physics, and the promise of technological applications. Novel phenomena emerge by spatial …

Nitrogen And Carbon Export To The Gulf Of Mexico By The Atchafalaya River, A Major Distributary Of The Mississippi River, April Elizabeth Bryantmason

LSU Doctoral Dissertations

Summer hypoxia in the Northern Gulf of Mexico has been attributed to large nutrient inputs, especially nitrate-nitrogen, from the Mississippi-Atchafalaya River system. The 2008 Gulf Hypoxia Action Plan calls for river corridor wetland restoration to reduce nitrate loads, but it is largely unknown how effective riverine wetland systems in the lower Mississippi River (MR) are for nitrate removal. This dissertation research examined nitrate and carbon export from the Atchafalaya River (AR) to: (1) determine nitrate processing by a river swamp basin under varied seasons, (2) investigate nitrate retention and processing in the AR during a major flood event, and (3) …

A Thermodynamic Framework For The Modeling And Optimization Of Crystallization Processes, David John Widenski

LSU Doctoral Dissertations

Crystallization is a widely used chemical engineering separation unit operation process. Since this technique can produce high purity products it is used for the industrial production of many chemical compounds, such as pharmaceuticals, agrochemicals, and fine chemicals. The production of these products is a multi-million dollar industry. Any methods to improve the production of these products would be highly valued. Thus, the main objective of this work is to target model-based optimal strategies for crystallization operations specifically targeting crystal size and crystal size distribution (CSD). In particular, take the knowledge gained and translate it into an economically and practically feasible …

Cluster Based Jamming And Countermeasures For Wireless Sensor Network Mac Protocols, David Trammell

LSU Doctoral Dissertations

A wireless sensor network (WSN) is a collection of wireless nodes, usually with limited computing resources and available energy. The medium access control layer (MAC layer) directly guides the radio hardware and manages access to the radio spectrum in controlled way. A top priority for a WSN MAC protocol is to conserve energy, however tailoring the algorithm for this purpose can create or expose a number of security vulnerabilities. In particular, a regular duty cycle makes a node vulnerable to periodic jamming attacks. This vulnerability limits the use of use of a WSN in applications requiring high levels of security. …

On The Synthesis, Characterization, And Magnetization Of Ln-M-X (Ln = Lanthanide; M = Ti-Cr, Cu, Mo, Pd; X = Al, Ga) Intermetallics, Michael James Kangas

LSU Doctoral Dissertations

The focus of the research presented herein was to grow single crystals of Ln-M-X (Ln = lanthanide; M = Ti-Cr, Cu, Mo, Pd; X = Al, Ga) intermetallic compounds and to characterize their crystal structures and physical properties. Overall, the flux growth technique facilitated a detailed analysis of previously known structure-types (LnM2Al20 (Ln = La, Ce, Pr, Yb; M = Ti, V, Cr), Ln6M4Al43 (Ln = Gd, Yb; M = Cr, Mo), and Yb2Pd3Ga9), as well as the synthesis and characterization of new compounds (LnCrxGa3 (Ln = Ho, Er; x ~ 0.13), YbCr2Al20-xFex (x ~ 0.2), Ln(Cu,Al,Ga)13-x, and Ln2PdGa12 (Ln …

Visualization Of Time-Varying Data From Atomistic Simulations And Computational Fluid Dynamics, Bidur Bohara

LSU Doctoral Dissertations

Time-varying data from simulations of dynamical systems are rich in spatio-temporal information. A key challenge is how to analyze such data for extracting useful information from the data and displaying spatially evolving features in the space-time domain of interest. We develop/implement multiple approaches toward visualization-based analysis of time-varying data obtained from two common types of dynamical simulations: molecular dynamics (MD) and computational fluid dynamics (CFD). We also make application case studies. Parallel first-principles molecular dynamics simulations produce massive amounts of time-varying three-dimensional scattered data representing atomic (molecular) configurations for material system being simulated. Rendering the atomic position-time series along with …

Strongly Correlated Electron Behavior In Transition Metal Intermetallics: Enhanced Thermoelectricity And Quantum Criticality In Fega₃ And Superconductivity In Nibi₃, Neel Saman Kumara Haldolaarachchige

LSU Doctoral Dissertations

TGa3 (T = Fe, Ru & Os) and RuIn3 are a class of isostructural intermetallic binary compounds with interesting physical and structural properties. These materials are non-magnetic, narrow band gap semiconductors with large n-type thermopower below room temperature. Chemical doping drastically changes physical properties and thermoelectric properties enhances by large percentage over the pure compounds. An important structural feature of FeGa3 is the fact that the four Fe atoms per unit cell exist as two Fe-Fe dimers. The nonmagnetic (NM) ground state of FeGa3 may be a consequence of the dimer spins being aligned in an antiparallel singlet state. We …

Pmi 5011 Regulates The Ubiquitin Proteasome System In Skeletal Muscle, Heather Christianne Kirk-Ballard

LSU Doctoral Dissertations

Insulin resistance in type 2 diabetes is associated with impaired glucose and protein metabolism in skeletal muscle. The impaired insulin signaling in skeletal muscle affects muscle mass by tilting the balance between skeletal muscle protein synthesis and degradation toward degradation, a process that is primarily regulated by the ubiquitin-proteasome system. Studies have shown that an extensively characterized ethanol extract of Artemisia dracunculus L (Russian Tarragon), termed PMI 5011, enhances insulin signaling in human primary skeletal muscle cells and in a rodent model of insulin resistance. The aim of this project is to determine if the effect of PMI 5011 on …

A Study Of Turnaround Efforts In High-Poverty Schools: Characteristics Of High Reliability Organizations That Determine Why Some Efforts Succeed And Others Fail, Angela Renee Lee

LSU Doctoral Dissertations

The inception of No Child Left Behind (NCLB) has focused national attention on improving the academic achievement of all students. In response to this federal legislation, educators, policymakers and others have sought remedies to turnaround chronically low-performing schools. The academic achievement outcomes of implementing such strategies have been mixed. Some schools have experienced clear, unambiguous growth. Others have remained stagnant. Others have regressed. Because of these mixed results, the research was designed to ascertain the factors that determine what makes these strategies succeed or fail. The researcher took a qualitative approach, the multiple case study design. Using the characteristics of …

Chemical Crystallography At The Interface Of Physics, Chemistry, And In Engineering: Structure Determination Of Highly Correlated Extended Solids, Main Group Compounds, Coordination Complexes, And Bioceramics, Gregory Todd Mccandless

LSU Doctoral Dissertations

Multi-disciplinary research is essential to address the major challenges in science, engineering, and medicine. For these three areas, crystallography has played and continues to play a huge role by providing researchers with the means to determine the structure of a compound and relate these to its properties. This dissertation is highly interdisciplinary, focusing on structure determination of complex systems and materials with tailored applications. This work includes the characterization by single crystal and powder X-ray diffraction of intermetallic extended solids, layered metal oxides, inorganic complexes, discrete organic molecules, and bioceramics. These projects range from modeling translational disorder with pseudo-hexagonal symmetry …

Some Tracking Problems For Aerospace Models With Input Constraints, Aleksandra Gruszka

LSU Doctoral Dissertations

We study tracking controller design problems for key models of planar vertical takeoff and landing (PVTOL) aircraft and unmanned air vehicles (UAVs). The novelty of our PVTOL work is the global boundedness of our controllers in the decoupled coordinates, the positive uniform lower bound on the thrust controller, the applicability of our work to cases where the velocity measurements may not be available, the uniform global asymptotic stability and uniform local exponential stability of our closed loop tracking dynamics, the generality of our class of trackable reference trajectories, and the input-to-state stability of the controller performance under actuator errors of …

Perpetual Requirements Engineering, Manuel Alfonso Peralta

LSU Doctoral Dissertations

This dissertation attempts to make a contribution within the fields of distributed systems, security, and formal verification. We provide a way to formally assess the impact of a given change in three different contexts. We have developed a logic based on Lewis’s Counterfactual Logic. First we show how our approach is applied to a standard sequential programming setting. Then, we show how a modified version of the logic can be used in the context of reactive systems and sensor networks. Last but not least we show how this logic can be used in the context of security systems. Traditionally, change …

Operational Methods For Evolution Equations, Lee Gregory Windsperger

LSU Doctoral Dissertations

This dissertation refines and further develops numerical methods for the inversion of the classical Laplace transform and explores the effectiveness of these methods when applied (a) to an asymptotic generalization of the Laplace transform for generalized functions and (b) to the numerical approximation of solutions of ill-posed evolution equations (e.g. backwards in time problems).

Chapter 1 of the dissertation reviews some of the key features of asymptotic Laplace transform theory and its application to evolution equations. Although some of the statements and results contain slight modifications and improvements, the material presented in Chapter 1 is known …

The Lost City: Examining The Relationship Between Science, Philosophy And The Atlantis Myth, Kimberly Hurd

LSU Doctoral Dissertations

Francis Bacon, long considered a minor figure in the founding of modern political thought, is now recognized as one of its foremost thinkers. Bacon not only championed a new type and method of scientific inquiry, he also developed a plan for how modern society could be re-ordered to accommodate and promote scientific progress. Bacon’s scientific writings cannot be wholly understood apart from his political writings, and many of his works combine the two topics so subtly that it is difficult to even place them in a definitive category. My project expands on the previous literature with a detailed analysis of …

Graham's Variety And Perverse Sheaves On The Nilpotent Cone, Amber Russell

LSU Doctoral Dissertations

In recent work, Graham has defined a variety which maps to the nilpotent cone, and which shares many properties with the Springer resolution. However, Graham's map is not an isomorphism over the principal orbit, and for type A in particular, its fibers have a nice relationship with the fundamental groups of the nilpotent orbits. The goal of this dissertation is to determine which simple perverse sheaves appear when the Decomposition Theorem for perverse sheaves is applied in Graham's setting for type A, and to begin to answer this question in the other types as well. In Chapter 1, we give …

An Exploration Of Reading Methods In First-Grade: Comparing The Basal Approach And Balanced Literacy, Richelle Leblanc Acosta

LSU Doctoral Dissertations

Few topics in education have sparked as much interest and debate as the teaching of reading. Throughout the past century, instructional approaches have come and gone but one thing has remained constant: the teacher. Behind every effective classroom lies a teacher. It is ultimately the teacher’s decisions that drive daily instruction in the classroom. But what is the best way for teachers to teach children how to read? For decades, researchers have plagued studies seeking to find the best method for accomplishing this. Just as students’ physical characteristics are very diverse, so too are their academic abilities. Reading teachers must …

Synthesis, Characterization, And Self-Assembly Of Porphyrins Conjugated To Superparamagnetic Colloidal Particles For Enhanced Photodynamic Therapy, Javoris Hollingsworth

LSU Doctoral Dissertations

Porphyrins and their derivatives are often used as photosensitizers in photodynamic therapy (PDT), which is a noninvasive antitumor treatment. The photochemical process for PDT involves exciting a photosensitizing agent with visible light, which induces cytotoxicity in the presence of oxygen as a result of forming reactive oxygen species (ROS). The ROS are the responsible components for invoking cell death and destruction of tumors. Although this mechanism is an effective cancer therapeutic, it still has many shortcomings. One major challenge of PDT concerns improving the tumor selectivity and specificity of photosensitizers because porphyrins have nonspecific affinity to tumor cells. The discussed …

A New Model For Coalition Formation Games, Alfred Samman

LSU Doctoral Dissertations

We present two broad categories of games, namely, group matching games and bottleneck routing games on grids. Borrowing ideas from coalition formation games, we introduce a new category of games which we call group matching games. We investigate how these games perform when agents are allowed to make selfish decisions that increase their individual payoffs versus when agents act towards the social benefit of the game as a whole. The Price of Anarchy (PoA) and Price of Stability (PoS) metrics are used to quantify these comparisons. We show that the PoA for a group matching game is at most kα …

An Evaluation Of Alternative Approaches For Simulating Animal Movement In Spatially-Explicit Individual-Based Models, Katherine Shepard Watkins

LSU Doctoral Dissertations

Simulating animal movement in spatially-explicit individual-based models (IBMs) is both challenging and critically important to accurately estimating population dynamics. I compared four distinct movement approaches or sub-models (restricted-area search, kinesis, event-based, and run and tumble) in a series of simulation experiments. I used an IBM loosely based on a small pelagic fish that simulated growth, mortality, and movement of a cohort on a 2-dimensional grid. First, I tested the sub-models calibrated (i.e., trained) with a genetic algorithm in one set of environmental conditions in three other novel environments. The sub-models performed well, except restricted-area search and event-based that needed to …

Adaptation As Anarchist: A Complexity Method For Ideology-Critique Of American Crime Narratives, Kristopher Mecholsky

LSU Doctoral Dissertations

Particularly through their relation to ideology, crime narrative adaptations expose the conflict between individuals and communities on one side and the State on the other. Adaptations take the already defamiliarizing effect of narrative and continue to defamiliarize, creating a narrative cubist effect through various audiences and discursive orderings of events. Hence, they question the ideological prefiguring that lies at the foundation of narrative understanding. Insofar as ideologies are simplified ways to legitimate actions and project images of identity, the fact that a society’s narratives necessarily inherit ideology from the State obscures that society and State’s inevitable deviations from their self-images. …

An Investigation Into Technology And Motivational Influences On Creativity And Product Output In Apparel Design Students, Charles Freeman

LSU Doctoral Dissertations

The purpose of this study was to investigate the application of a social psychological theoretical framework to the study of creativity in apparel design, with a focus on technological engagement and motivational factors. A sample of 32 apparel design students from two major southeastern universities were selected to complete a self-report instruments regarding motivation and technological engagement. Students completed the Abbreviated Torrance Test for Adults (ATTA) as well as a design brief. Design illustrations were evaluated by a panel of expert judges in the field of apparel design using a consensual assessment technique (CAT). Results indicate levels of technology and …

Hadronic Physics From Extensive Air Showers, Guofeng Yuan

LSU Doctoral Dissertations

Although cosmic rays were discovered exactly one century ago, the most fundamental questions about them are still not answered, especially the origin and composition of ultra-high energy cosmic rays (UHECR). The Pierre Auger Observatory (PAO) is constructed with the goal of solving these mysteries. The PAO uses hybrid design and take advantage of both the air fluorescence and surface array technique. Since its debut in 2004, PAO has published several important scientific results.

The most probable candidate for UHECR composition is proton or iron nucleus. The two candidates do show differences in both fluorescence detector (FD) signal and in the …

Early Behavior Problems In School, Juvenile Delinquency, And Adult Incarceration: A Longitudinal Examination Of Pathways To Crime Among A Ten-Year Birth Cohort In Louisiana, Xian Guan

LSU Doctoral Dissertations

This study utilizes data resources from three state-level departments in Louisiana, Department of Education (DOE), Office of Juvenile Justice (OJJ), and Department of Public Safety and Corrections (DOC), during the period 1996-2008. The sample involves 7th- 12th graders in DOE who were born between 1980 and 1989, with a sample size of N = 408,700 in total. There are two major parts in this study: (1) examining the school-level risk factors among four different offending patterns and making two comparisons among them: the early starters of crime (n = 14,346) vs. late starters (n = 17,107), and the adolescent-limiteds (n …

Paradoxes And Consumer Decision-Making, Carolyn Popp Garity

LSU Doctoral Dissertations

Consumers often find themselves faced with conflicting evaluations in which they identify both positive and negative aspects of a purchase or consumption experience. A paradox occurs when the individual is aware of the conflicting evaluations and experiences tension as a result. While there are strong potential implications of paradox, marketing research has been slow to study consumption paradoxes. As a result, many deficiencies exist in the literature, including no consensus as to the definition of consumer paradox, insufficient quantitative measurement, and limited knowledge of the antecedents and consequences of paradox. This dissertation was conducted to address these shortcomings. Essay one …