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Method Development For The Assignment Of Nmr Peaks And The Determination Of Quaternary Protein Structure Using Reductive Methylation, Pamlea Nicole Brady

LSU Doctoral Dissertations

The work described herein is centered on reductive methylation, a chemical modification reaction, which allows for the introduction of methyl groups at the primary amines of the lysine side chain and at the N-terminus. The resulting methyl groups are effective probes for the study of protein structure and dynamics using nuclear magnetic resonance spectroscopy (NMR). Described herein is work conducted on the development of tools for the study of protein structure using reductive methylation, highlighting options for addressing limitations of the labeling method encountered by its practical use. Chapter 1 serves as a brief introduction to protein structure and the …

Investigating The Photorecombination Dynamics In Molecular High-Harmonic Spectra, Benjamin Parker Wilson

LSU Doctoral Dissertations

The work presented in this dissertation will relate the photorecombination dynamics to photoionization dynamics in SF6 utilizing the self-probing mechanism, high harmonic generation (HHG). This work specifically aims to establish parameters for which the comparison is applicable and the macroscopic complications inherent in HHG do not interfere with the extraction of dynamic information. The first part of this work established the macroscopic experimental apparatus necessary for consistent spectroscopic observation. It is shown that using a gas jet that is an order of magnitude shorter than the Rayleigh length of the driving laser results in more consistent harmonic spatial profiles and …

Towards The Realization Of Systematic, Self-Consistent Typical Medium Theory For Interacting Disordered Systems, Chinedu Ekuma Ekuma

LSU Doctoral Dissertations

This work is devoted to the development of a systematic method for studying electron localization. The developed method is Typical Medium Dynamical Cluster Approximation (TMDCA) using the Anderson-Hubbard model. The TMDCA incorporates non-local correlations beyond the local typical environment in a self-consistent way utilizing the momentum resolved typical-density-of-states and the non-local hybridization function to characterize the localization transition. For the (non-interacting) Anderson model, I show that the TMDCA provides a proper description of the Anderson localization transition in one, two, and three dimensions. In three-dimensions, as a function of cluster size, the TMDCA systematically recovers the re-entrance behavior of the …

Chemical Structure And Dynamics In Laminar Flame Propagation, Mohsen Ayoobi

LSU Doctoral Dissertations

The objective of this dissertation is to investigate fundamental aspects of premixed flame structures as well as flame dynamics that arise due to conjugate heat transfer in narrow channels. Laminar premixed combustion simulations in narrow 2D channels show that conjugate heat transfer allows for combustion of mixtures at small scales that are not flammable at normal conditions. To investigate the impact of conjugate heat transfer, preheated 1D cases with premixed H2/Air fuel are simulated for a wide range of operating conditions based on inlet temperature and equivalence ratio. For post-processing, Chemical Explosive Mode Analysis (CEMA, an eigen-analysis technique) is used …

Constitutive Modeling And Experiments For The Micro And Nano Behaviors In Metals, Cheng Zhang

LSU Doctoral Dissertations

This work addresses the micro- and nano-behaviors in metals through constitutive modeling and experiments. The size effect encountered during nanoindentation experiments, which is known as indentation size effect (ISE), is investigated for metal materials. The ISE is believed to be related with the strain gradient at small indentation depths. Geometrically necessary dislocations (GNDs) are formed in order to accommodate the strain gradient, which results in the increase in the material hardness. The grain boundaries in polycrystalline materials play an important role on the material hardness during nanoindentation experiments as there is a soften-hardening segment in the curve of hardness as …

Peer Coaching Effects On Targeted Teaching Behaviors And Teacher Self-Efficacy In An Early Field Experience, Deanna Kay Rice

LSU Doctoral Dissertations

Abstract This study examined the effect of peer coaching on the development of effective teaching behaviors and teacher self-efficacy of education students in an early field experience. The convenience sample (N = 99) included undergraduate students enrolled in a required foundational course in special education at a large public university in the southern United States. Training methods included online video instruction on targeted effective and ineffective teaching behaviors. The effective behaviors included (a) established student learning objective prior to beginning a lesson, (b) explained and/or modeled how pupil can discover answer or solve a problem, (c) checked for understanding by …

Three Essays On Economic Analysis Of Production Systems Of U.S. Grass-Fed Beef Industry, Basu Deb Bhandari

LSU Doctoral Dissertations

This dissertation research consists of three essays. The first two studies analyze experimental research data based on three pasture systems for grass-fed beef (GFB) production in the Gulf Coast Region. System 1 included bermudagrass and ryegrass; System 2 included bermudagrass, ryegrass, rye, dallisgrass, and clover mixtures (red, white, and berseem clovers); and System 3 included bermudagrass, soybean, sorghum sudan hybrid, ryegrass, rye, dallisgrass, and clover mixtures (red, white, and berseem clovers). Fifty-four Fall-born steers were weaned in May and grouped into nine groups and randomly blocked into treatments and replicates. Inputs and output data were recorded on a daily basis. …

Rényi Quantum Conditional Mutual Information And Parity Quantum Optical Metrology, Kaushik Parasuram Seshadreesan

LSU Doctoral Dissertations

This is a two-part thesis strung together by a common underlying theme—quantum correlations. We present some new characterizations and quantifications of quantum correlations and an application of one such correlation—entanglement—for quantum technology.

In Part I of the thesis, we use a Rényi generalization of the quantum conditional mutual information (QCMI) to define and study new measures of quantum entanglement and quantum discord. In particular, using a quantity derived from a Rényi QCMI, we introduce: a) the geometric squashed entanglement, a faithful entanglement measure, which is a lower bound on the squashed entanglement and which reduces to the geometric measure of …

Applications Of Large Eddy Simulation To Study Flow And Sediment Transport In Open Channel Flows, Getnet Baynesagne Agegnehu

LSU Doctoral Dissertations

The motivation of this study is to extend applications of Large Eddy Simulation (LES) for typical open channel flows to elucidate the time dependent three dimensional flow and sediment transport features which are usually difficult to measure in experiments. Detailed investigations are performed on the unsteady features and, in particular, turbulent structures of the flow to demonstrate the great potential of eddy resolving methods. The instantaneous flow and sediment transport fields are investigated together with the existence of coherent structures. These structures together with ejection events (u' < 0, w' > 0), are responsible for the vertical and lateral transport of suspended sediment from …

Examining The Supervisor-Similarity And Work-Family Conflict Relationship: Is Family-Supportive Supervision A Mediator?, Chela M. White-Ramsey

LSU Doctoral Dissertations

To say that interest in work-family conflict has increased is an understatement. With the number of dual-earner households increasing, the diversification of the workforce, and women quickly moving into industries that were once primarily male-dominated, the work-family literature is filled with various intonations of the concept. Drawing on insights from social identity and self-categorization theories, this dissertation examined how supervisor-subordinate demographic similarity might relate to the provision of family-supportive supervision and work-family conflict. 102 members of a professional organization dedicated to women who work in technology were surveyed to evaluate whether or not supervisor-subordinate racial and gender similarity would predict …

Dwelling Poetically, Proceeding Orphically: The Platonic Tradition And The Heideggerian Humanism Of Ernesto Grassi, Geoffrey Alexander Leeves Bain

LSU Doctoral Dissertations

Martin Heidegger exerted an immense influence over twentieth century thought by providing profound insights into the nature of Being as well as scathing social critiques, focused on the destructive force of late modern technological reductionism. As part of Heidegger’s project, he elaborated upon a sophisticated history of Being in which two great monsters of Platonism and Humanism are cast as Antichrist and False Prophet. Subsequently, however, his own student Ernesto Grassi argued that Renaissance Humanism was not a stepping stone towards subjectivism and technological thinking, but rather stood in conformity with the fundamental essence of Heidegger’s own project. This study …

Excluding Two Minors Of The Petersen Graph, Adam Beau Ferguson

LSU Doctoral Dissertations

In this dissertation, we begin with a brief survey of the Petersen graph and its role in graph theory. We will then develop an alternative decomposition to clique sums for 3-connected graphs, called T-sums. This decomposition will be used in Chapter 2 to completely characterize those graphs which have no P_3 minor, where P_3 is a graph with 7 vertices, 12 edges, and is isomorphic to the graph created by contracting three edges of a perfect matching of the Petersen Graph. In Chapter 3, we determine the structure of any large internally 4-connected graph which has no P_2 minor, where …

Physics And Applications Of A Pdms Based Centrifugal Microfluidic System, Ziliang Cai

LSU Doctoral Dissertations

The objective of this research work is to develop a centrifugal microfluidic system for general purposes based on microfabrication technologies including SU-8 photolithography, polydimethylsiloxane (PDMS) casting. The main contribution of this research is to integrate a flyball governor system into the polymer based centrifugal microfluidic platform. A series of function units are developed based on this unique mechanism. In the first part, three pinch valve systems were designed and tested. The first one is based on the magnetic force and the second one is on the basis of spring force and the last one is a membrane valve. All valving …

A Science Education Study Using Visual Cognition And Eye Tracking To Explore Medication Selection In The Novice Versus Expert Nurse Anesthetist, Aimee Ladreyt Badeaux

LSU Doctoral Dissertations

The purpose of this science education study is to explore visual cognition and eye tracking during medication selection in the student nurse anesthetist (first year and second year students) and the expert nurse anesthetist. The first phase of this study consisted of the selection of a specific medication (target) from an array of medications via computer simulation. Various dependent variables were recorded to examine performance (reaction time and accuracy), and the allocation of visual attention was measured with eye tracking (dwell proportion, verification, and guidance). The second phase of this study included the administration of a demographic and post experiment …

Large-Scale Geometric Data Decomposition, Processing And Structured Mesh Generation, Wuyi Yu

LSU Doctoral Dissertations

Mesh generation is a fundamental and critical problem in geometric data modeling and processing. In most scientific and engineering tasks that involve numerical computations and simulations on 2D/3D regions or on curved geometric objects, discretizing or approximating the geometric data using a polygonal or polyhedral meshes is always the first step of the procedure. The quality of this tessellation often dictates the subsequent computation accuracy, efficiency, and numerical stability. When compared with unstructured meshes, the structured meshes are favored in many scientific/engineering tasks due to their good properties. However, generating high-quality structured mesh remains challenging, especially for complex or large-scale …

Developing Co-Current And Counter-Current Spray Drying Computational Fluid Dynamics (Cfd) Simulation Studies To Predict The Quality Of Microencapsulated Fish Oil With Egg White Hydrolysates Powders, Kevin Estuardo Mis Solval

LSU Doctoral Dissertations

Eggs are an excellent source of high quality protein containing all essential amino acids (EAA) including leucine. Food-grade protein hydrolysates can enhance the growth of lactic acid bacteria (LAB). Thermal degradation of bioactives normally occurs during microencapsulation by spray drying. Spray drying modeling using computational tools is essential to engineer new food powders and to minimize and thermal degradation of bioactives. The first chapter of this work discusses the optimization of an enzymatic process in terms of reaction temperature, pH, enzyme:substrate ratio, and reaction time using a response surface methodology (RSM) to produce food-grade protein hydrolysates from egg whites (EWH). …

Fish Assemblage Structure, Distribution, And Trophic Ecology At Northwestern Gulf Of Mexico Banks, Todd Langland

LSU Doctoral Dissertations

The northwest Gulf of Mexico (Gulf) shelf-edge banks both provide unique hard bottom habitat and support the northernmost coral reefs on the North American continental shelf in a region that is generally characterized by low relief, soft sediments. The habitat value of many of these banks has led to their designation as Habitat Areas of Particular Concern (HAPC) and the Flower Garden Banks National Marine Sanctuary (FGBNMS). However, little is known about the fisheries resources and dynamics of the banks outside the FGBNMS. This study had three main objectives: 1) define reef fish assemblages at northwestern Gulf shelf-edge banks and …

Computational Studies On Bimetallic Catalysis And X-Ray Absorption Spectroscopy, Sayakkarage R. G. Fernando

LSU Doctoral Dissertations

Computational studies are very important to gain an insight into reaction mechanisms and in interpreting and understanding complicated experimental observations. This report contains a discussion on computational studies performed on bimetallic catalysis and on X-ray absorption spectroscopy of insulators. The viability of a bimetallic rhodium and cobalt catalysts for industrially important hydroformylation and aldehyde-water shift catalysis (AWS) is discussed. Density functional theory (DFT) studies were used for bimetallic catalysis and time-dependent DFT studies were used for excited state dynamics. These studies were performed using Gaussian 09 package and NWChem. Hydroformylation is experimentally performed in acetone and 30% water/acetone systems and …

Wavelets, Coorbit Theory, And Projective Representations, Amer Hasan Darweesh

LSU Doctoral Dissertations

Banach spaces of functions, or more generally, of distributions are one of the main topics in analysis. In this thesis, we present an abstract framework for construction of invariant Banach function spaces from projective group representations. Coorbit theory gives a unified method to construct invariant Banach function spaces via representations of Lie groups. This theory was introduced by \Fch\, and \Gro\, in \cite{FG,FG1, FG2,FG3} and then extended in \cite{CO2}. We generalize this concept by constructing coorbit spaces using projective representation which is first studied by O. Christensen in \cite{O1}. This allows us to describe wider classes of function spaces as …

Boron Functionalization Of Bodipy Dyes, And Their Evaluation As Bioimaging Agents, Alex Long Nguyen

LSU Doctoral Dissertations

BODIPY, also known as “porphyrin’s little sister,” belongs to a class of fluorescent dyes. It contains a dipyrromethene π-system with a disubstituted boron atom. The basic 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) is known for its numerous useful applications in the fields of biology and materials. Modification of this well-known fluorophore has been shown to change its photophysical and chemical properties. There has been great interest in the modification at the boron center in recent years for synthesizing new dyads and cascade-type dyes. This work focuses on functionalization at the boron center with carbon and oxygen nucleophiles for further investigation as bioimaging agents. Chapter …

Sourcing And Framing Analysis Of Source Messages In The Coverage Of Armed Conflicts By American And British Foreign Reporters, Ellada Gamreklidze

LSU Doctoral Dissertations

This dissertation contributes to closing several gaps in mass communication scholarship as well as indicates new avenues for further research in the area of sourcing and framing. This study explored whether reliance on official sources in foreign reporting of international crises is as heavy as the hypothesis predicts, and, by studying messages delivered by official sources in this coverage, revealed how those messages were framed. The results showed that officials were dominant sources of information in all the three media outlets studied. The results also supported the argument that the same indexing mechanisms are at force in foreign reporting and …

Holocene Palynology Of The Gulf Of Papua, Papua New Guinea: Using Modern Palynomorph Distribution To Better Constrain Paleoenvironmental Changes, Marie Louise Thomas

LSU Doctoral Dissertations

Multiple NSF (National Science Foundation)-funded MARGINS Source-to-Sink cruises were conducted in the Gulf of Papua (GoP), Papua New Guinea (PNG), from 2003 through 2005 to better understand how sediment is created, transported, and deposited. Although much work has been done on the data collected during these cruises, palynological analysis has never been conducted on the hundreds of available cores. The first phase of this project (Chapters 2 and 3) examines the connection between modern depositional regimes in the GoP and species assemblages recovered. Statistical analysis of palynomaceral assemblages (Chapter 2) indicates a correlation between their distribution and bathymetry, sedimentation rate, …

A Spatial Dynamic Model Of Population Changes In A Vulnerable Coastal Environment, Kenan Li

LSU Doctoral Dissertations

Achieving coastal sustainability in low-lying coastal areas is a great challenge. This study developed a spatial dynamic model to study the coupled natural-human responses in the form of population changes in the Lower Mississippi River Basin region. The goal was to identify the key social-economic factors (utility) and selected environmental factors (such as hazards damage, elevation, and subsidence rate) that affect population changes, as well as how population changes affect the local utility and the local environment reciprocally. The study area was partitioned into the “north’ and the “south” by a hypothetical boundary to test the differences of the emergence. …

Connected Vehicle Technology: User And System Performance Characteristics, Osama Abdulmonaem Thabet Osman

LSU Doctoral Dissertations

The emerging connected vehicle (CV) technology plays a promising role in providing more operable and safer transportation environments. Yet, many questions remain unanswered as to how various user and system characteristics of CV-enabled networks can shape the successful implementation of the technology to maximize the return on investment. This research attempts to capture the effect of multiple factors such as traffic density, market penetration, and transmission range on the communication stability and overall network performance by developing a new CONnectivity ROBustness (CONROB) model. The model was tested with data collected from microscopic simulation of a 195 sq-mile traffic network and …

An Exploration Of How Closely Upper Elementary Magnet School Reading Teachers' Perceptions Of Evidence-Based Practices In Reading Compared To Actual Practices In Their Classrooms, Rhonda Ann Cross

LSU Doctoral Dissertations

The purpose of this study was to explore how closely upper elementary magnet school reading teachers’ perceptions of evidenced-based practices in reading compared to actual practices in their classrooms. Literacy instruction, beginning in the third grade, places more emphasis on comprehension and higher expectations on the students than in the early elementary grades. There has been little research conducted on how teacher beliefs about reading and their actual instructional practices affect reading scores on national tests. Perhaps in the understanding of teachers’ beliefs about evidenced-based practices and the actual instructional practices used in the classroom can help in the development …

Ambit Of Multiphase Cfd In Modelling Transport Processes Related To Oil Spill Scenario And Microfluidics, Abhijit Rao

LSU Doctoral Dissertations

During the ‘Deepwater Horizon’ accident in the deep sea in 2010, about 4.9 million barrels of oil was released into the Gulf of Mexico, making the spill one of the worst ocean spills in recent times. To mitigate the ill effects of the event on the environment, subsea injection of dispersants was carried out. Dispersant addition lowers the interfacial tension at oil/water interface and presence of local turbulence enhances the droplet disintegration process. The oil droplets contain a plethora of hydrocarbons which are soluble in water. In deep spill scenarios, droplets spend large amounts of time in water column; hence, …

Development Of New Linking Chemistry With The Fac-{Re(Co)3}+ Core For Eventual Applications In Radiopharmaceuticals In Imaging And Therapy, Aponsu Meregngna Pramuditha Lakmi Abhayawardhana

LSU Doctoral Dissertations

The facile labeling of biomolecules with a radionuclide is a key goal in radiopharmaceutical development. This study explores two different ligand systems for fac-[Re(CO)3L]+ complexes, that could be used in bioconjugation. The first approach uses a tridentate ligand having a sulfonamide linkage and modeled on previously evaluated fac-[Re(CO)3(N(SO2R)dpa)]PF6 complexes. The present goal was to develop new related sulfonamide complexes with more hydrophilic ligands designed to avoid the bioavailability problems that would plague the N(SO2R)dpa ligand system. A series of fac-[Re(CO)3(N(SO2R)dien)]PF6 complexes with different R groups linked to the central nitrogen of a symmetric tridentate sulfonamides were synthesized with the aim …

Evaluating Technical Adequacy Features Of Sentence Verification Technique As A General Outcome Measure Of Content Knowledge, Ren&Eacutee E. Lastrapes

LSU Doctoral Dissertations

Once students have mastered the mechanics of reading, they are expected to learn new material by reading. This new material, however, becomes increasingly more complex as students enter upper elementary and especially middle and high school. If students fail to comprehend what they read, they risk failure in content courses such as science and social studies. Early assessment of risk and appropriate response to that risk is a goal of effective education. One problem with the risk reduction sequence is that there are limited formative assessments that have been validated as technically adequate for assessing content knowledge. The present study …

First-Principles And Many-Body Methods: Implementations And Applications To Study Spintronic Materials, Ryky Nelson

LSU Doctoral Dissertations

Diluted magnetic semiconductors (DMSs) and magnetoresistive materials are instrumental for the development of spintronic technology. Before we are able to engineer spintronic devices, it is necessary to understand the properties of materials from which spintronic devices are made, otherwise time and other resources will be wasted. In this thesis, we investigate some aspects of diluted magnetic semiconductors and a magnetoresistive material Ta2PdSe6 with first-principle and many-body methods. Particularly, we investigate the Mn valence in (Ga,Mn)N and derive low-energy models of (Ga,Mn)N by making use of a first-principles Wannier-function analysis. Additionally, we also study the disorder-driven localization in DMSs with the …

Anisotropic Spacetimes And Black Hole Interiors In Loop Quantum Gravity, Anton Joe

LSU Doctoral Dissertations

This thesis deals with understanding quantum gravitational effects in those anisotropic spacetimes which serve as black hole interiors. Two types of spacetime are investigated. Kantowski-Sachs spacetime and Bianchi-III LRS spacetime. The former, in vacuum, is the interor spacetime for Schwarzschild black holes. The latter is the interior for higher genus black holes. These spacetimes are studied in the context of loop quantum cosmology. Using effective dynamics of loop quantum cosmology, the behavior of expansion and shear scalars in different proposed quantizations of the Kantowski-Sachs spacetime with matter is investigated. It is found that out of the various proposed choices, there …