Physical Sciences and Mathematics Commons^™

Framework For Algorithmically Optimizing Longitudinal Health Outcomes: Examples In Cancer Radiotherapy And Occupational Radiation Protection, Lydia Joyce Wilson

LSU Doctoral Dissertations

Background: Advancements in the treatment of non-infectious disease have enabled survival rates to steadily increase in recent decades (e.g., diabetes, heart disease, and cancer). Epidemiological studies have revealed that the treatments for these diseases can have life-threatening and/or life–altering effects. Thus, realizing the full beneficial potential of advanced treatments necessitates new tools to algorithmically consider all major components of the health outcome, including benefit and detriment. The goal of this dissertation was to develop a framework for improving projected health outcomes following planned radiation exposures in consideration of all beneficial and detrimental, early and late, and fatal and non-fatal …

Reflection Positivity: A Quantum Field Theory Connection, Joseph W. Grenier

LSU Doctoral Dissertations

At the heart of constructive quantum field theory lies reflection positivity. Through its use one may extend results for a Euclidean field theory to a relativistic theory. In this dissertation we connect functorial and constructive quantum field theories through reflection positivity. In 2014 Santosh Kandel constructed examples of $d$-dimensional functorial QFTs when $d$ is even. We define functorial reflection positivity and show that this functorial theory is a reflection positive theory. We go on to show that every reflection positive theory produces a reflection positive Hilbert space. Iterated doubles are then introduced and used as a starting point to produce …

Modeling Crowd Feedback In The Mobile App Market, Grant S. Williams

LSU Doctoral Dissertations

Mobile application (app) stores, such as Google Play and the Apple App Store, have recently emerged as a new model of online distribution platform. These stores have expanded in size in the past five years to host millions of apps, offering end-users of mobile software virtually unlimited options to choose from. In such a competitive market, no app is too big to fail. In fact, recent evidence has shown that most apps lose their users within the first 90 days after initial release. Therefore, app developers have to remain up-to-date with their end-users’ needs in order to survive. Staying close …

Improving Coupled Enzyme Assays With Capillary Electrophoresis, Thu Hoai Nguyen

LSU Doctoral Dissertations

The goal of this project is to address limitations of coupled enzyme assays using capillary electrophoresis (CE). In some enzyme assays, it is ineffective to directly detect products and substrates spectroscopically (absorption or fluorescence). Coupling the enzyme-catalyzed reaction of interest with another enzyme-catalyzed reaction allows for indirect detection of product formation or substrate depletion for the target enzyme. While conventional coupled enzyme assays are facile for kinetic measurements, they can be problematic for inhibition screening due to spectral and inhibitor interferences. To address these limitations of coupled assays, CE has been used to develop enzyme assays for acetyl-coenzyme A carboxylase …

Optimization Of Quantum Optical Metrology Systems, Nicholas Michael Studer

LSU Doctoral Dissertations

It can be said that all of humanity's efforts can be understood as a problem of optimization. We each have a natural sense of what is ``good'' or ``bad'' and thus our actions tend towards maximizing -- or optimizing -- some notion of good and minimizing those things we perceive as bad or undesirable.

Within the sciences, the greatest form of good is knowledge. It is this pursuit of knowledge that leads to not only life-saving innovations and technology, but also to furthering our understanding of our natural world and driving our philosophical pursuits.

The principle method of obtaining knowledge …

Vulnerability Of Industrial Facilities In The Lower Mississippi River Industrial Corridor To Relative Sea Level Rise And Tropical Cyclone Storm Surge, Joseph Blake Harris

LSU Doctoral Dissertations

Relative sea level rise (RSLR) and tropical cyclone-induced storm surge are major threats to the Lower Mississippi River Industrial Corridor (LMRIC) which has approximately 120 industrial complexes located within the corridor. Spatial interpolation methods were applied to the 2004 National Oceanic and Atmospheric published Technical Report #50 subsidence dataset and cross-validation techniques were used to determine the accuracy of each method. Digital elevation models (DEMs) were created for the years 2025, 2050, and 2075, based on these predictive surface of subsidence rates. Future DEMs were utilized to model RSLR and determine the extent of storm surge on the LMRIC by …

Precision Of Parameter Estimation In Quantum Metrology, Chenglong You

LSU Doctoral Dissertations

The fundamental precision limit of an interferometer is crucial since it bounds the best possible sensitivity one could achieve using such a device. This thesis will focus on several different interferometers and try to give the ultimate precision bounds by carefully counting all the resources used in the interferometers.

The thesis begins with the basics of the quantum state of light. The fundamentals of quantum metrology are also reviewed and discussed. More specifically, the terminology of classical and quantum Cram\'er-Rao bound and classical and quantum Fisher information are introduced.

Chapter 3 discusses the conclusive precision bounds in two-mode interferometer such …

Fate Of Selected Pollutants Of Concern On Particulate Matter (Pm) Surface, Ajit Ghimire

LSU Doctoral Dissertations

This research focuses on the environmental fate of particle associated pollutants such as Polybrominated Diphenyl Ethers (PBDEs), Polyaromatic Hydrocarbons (PAHs), and Environmentally Persistent Free Radicals (EPFRs) with a special emphasis on their transformation due to interaction with a matrix or co-pollutants. It encompasses two approaches to the stated problems: analysis of samples collected in the environment and laboratory simulation of the molecular transformations.

The PBDE studies relied on the ambient air Particulate Matter (PM) samples collected from Bangkok, Thailand. Results showed the presence of various PBDE homologs from tri- to hepta-PBDEs on both PM_2.5and Total Suspended Particle (TSP) …

Infrared Laser Ablation For Biomolecule Sampling, Kelin Wang

LSU Doctoral Dissertations

In this research, an infrared laser at a wavelength of 3 µm was used to ablate material from tissue sections for biomolecule analysis. Pulsed infrared (IR) irradiation of tissue with a focused laser beam efficiently removed biomolecules, such as proteins, enzymes, DNA, and RNA from tissue sections for further analysis. In a proteomics project, matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) was used to determine regions of interest (ROI) for laser ablation. The matrix was then washed off. By overlaying the MSI generated heat-map, the section was sampled using IR laser ablation and custom stage-control software. Two ROI were selected …

Cationic Cobalt (Ii) Hydroformylation, Drew Michael Hood

LSU Doctoral Dissertations

While investigating a bimetallic cobalt hydroformylation catalyst a new class of monometallic cationic cobalt (II) hydroformylation catalyst were discovered. These newly discovered catalyst proved to be very unique with high hydroformylation activity under mild conditions. The pre-catalyst were characterized using various methods including NMR, EPR, MS, and X-ray crystallography. Similarly the active catalyst was also investigated using NMR, EPR, FTIR, and X-ray crystallography. Various catalyst modifications were investigated for their effects on hydroformylation activity. Likewise various reaction parameters were probed to determine their effect on hydroformylation activity. Finally the best cationic cobalt (II) catalyst were directly compared to industry standards …

The Modern Mississippi: Provenance Indicators And Human Impact, Brittney Anne Gregory

LSU Doctoral Dissertations

Given the significant degree to which the modern Mississippi River and its tributaries have been altered through dams, levees, and diversions, it is important to understand how sediment is transported from source to sink. The objective of this dissertation is to explore how the modern Mississippi River transports sediment from its tributaries to its delta using three independent proxies. Provenance indicators have traditionally been an effective way with which to characterize sediment transport in large river systems. First, detrital U-Pb zircon dating is used to investigate modern flux and possible anthropogenic influences on coarse-grained sediment within the modern Mississippi River. …

Deltaic Wetland Dynamics From Seasonal To Centennial Scales, Giancarlo A. Restreppo

LSU Doctoral Dissertations

The lower plain of the Mississippi River Delta contains approximately five coastal sedimentary basins that are topographically defined, and one shelf-crossing depocenter (the Birds Foot Delta). These depositional systems receive varying quantities of sediment from fluvial and marine sources and have rates of coastal land loss that are roughly inversely proportional to fluvial sediment supply. To combat land loss along these regions, Louisiana has launched a historic campaign to sustain and regrow coastal lands using, in part, river sediment diversions. Fine sediments constitute the majority of sediment load in the Mississippi River, but are under-studied with respect to dispersal processes, …

Investigating Cationic Metal Centers For Hydroformylation, Ryan Alexander Johnson

LSU Doctoral Dissertations

Bimetallic cooperativity can potentially increase activity of reactions. This concept is another way to increase reactivity besides simply focusing on the steric and electronic effects of a ligand. A binucleating tetrasphosphine ligand has been developed to showcase bimetallic cooperativity between two rhodium metal centers. Hydroformylation is a widely used industrial process to produce aldehydes from alkenes, H₂, and CO. The dirhodium catalyst, [Rh₂(μ-CO)(CO)₃(rac-et,ph-P4-Ph)](BF₄)₂,is highly active leading to favorable results when using a DMF/water solvent system, 1-hexene, 90 psi 1:1 H₂/CO, and 90° C: initial turnover frequency …

Iron Mediated Organic Preservation In A River Influenced Continental Margin, Neha Ajit Ghaisas

LSU Doctoral Dissertations

Continental margins such as the Mississippi river influenced Louisiana shelf (MIS), are important land-ocean interfaces where excessive water column productivity and rapid burial results in large amounts of organic carbon (OC) being sequestered in the sediments. The preservation of OC in sediments is controlled by a number of processes among which mineral-OC interactions are considered to be more important. Specifically, the interactions between sediment iron (Fe) species and OC have been shown to promote carbon preservation. However, the exact nature of preservation mechanism is not well understood and is based on limited global data, which specifically lacks estimates from large …

Evaluating Seasonal Nutrient Fluxes In Emerging And Eroding Wetlands Of The Louisiana Delta Plain, Kiran Upreti

LSU Doctoral Dissertations

Deltaic wetlands can ameliorate high NO₃^- loads via denitrification, a dominant NO₃^- reduction pathway in inland and coastal habitats. Dissimilatory Nitrate Reduction to Ammonia (DNRA), in contrast to denitrification, conserves N within the system and has been found to be favored over denitrification with increase in salinity and temperature. There are no studies in the Louisiana Deltaic plain with simultaneous estimation of denitrification and DNRA. Increased P availability has been shown to increase denitrification so it is essential to understand P biogeochemistry when studying N cycle. Here, we evaluated net denitrification using N₂:Ar and …

Phase Estimation In Linear And Nonlinear Interferometers, Sushovit Adhikari

LSU Doctoral Dissertations

Phase estimation has a wide range of applications. Over the years, several strategies have been studied to improve precision in phase estimation. These strategies include using exotic quantum states to quantum detection schemes. This dissertation summarizes my effort in improving the precision of phase estimation with a linear and nonlinear interferometer.

Chapter 1 introduces quantum optics and quantum metrology. I introduce all relevant quantum states of light used. We also look into tools and terminologies of quantum metrology such as Fisher information, shot-noise limit, Heisenberg limit, etc., along with examples of phase estimation with a Mach-Zehnder interferometer.

In Chapter 2, …

Evaluation Of Naturally Occurring Radioactive Material In Seafood From The Gulf Of Mexico, Charles Algeo Wilson Iv

LSU Doctoral Dissertations

Radioactive disintegration of naturally occurring radioactive material was modeled with high precision and no assumptions to better understand serial decay in high order disequibrlia. This model helped develop a new method of quick analysis of NORM, where radioactivity can be measured with reasonable certainty before secular equilibrium is established. This approach was a significant improvement on previous similar approaches, halving time required for the same results and reduced wait time compared to classical approaches by 92%. Consequentially, NORM was measured in selected seafood samples from three areas in the Gulf of Mexico. Red Snapper, Red Drum, Northern Whiting, Spotted Trout …

Monitoring Sediment Dynamics And Vegetation Competition Based On Micro-Topography And Terrestrial Lidar For Wetland Restoration, Xukai Zhang

LSU Doctoral Dissertations

With the ability to attenuate wave and limit erosion, coastal wetlands are important to protect shoreline for coastal communities. Micro-topography in coastal wetlands has a significant influence on hydrology, habitat variability and ecosystem functions. However, when mapping micro-topography by terrestrial LiDAR in coastal environments, the coverage of dense vegetation leads to a relatively low chance of laser penetration through the canopy to the ground. This dissertation proposes a rapid and flexible terrain mapping solution for the densely vegetated coastal environment by integrating crown structure from terrestrial LiDAR with terrain samples from GPS. The validated results in the study site demonstrate …

An Airlifted Tidal Mesocosm For Oil Degradation Studies, Daniel Christopher Alt

LSU Doctoral Dissertations

Mesocosms were constructed to allow scientists to isolate variables in a microtidal marsh environment, mimicking the natural conditions found in Terrebonne Bay. The control offered by these mesocosms is given by a process control system that takes user inputs and automates water movement. Twelve mesocosms were constructed, each holding 4.02 m³ (142 ft³) of marsh soil and 3.88 m³ (137 ft³) of water to give 3 experimental levels and a control, all in triplicate.

Each mesocosms that was constructed contained marsh plants in soil plugs 9 feet in diameter and 3 feet deep. These …

A Multi-Proxy Approach To Refining Paleotempestology Records On The Northern Gulf Of Mexico Coast, Marianne Elizabeth Dietz

LSU Doctoral Dissertations

Reconstructing pre-historic hurricane activity is typically accomplished through the analysis of sandy overwash deposits identified in coastal lake settings. This method has been used successfully in many parts of the world and can extend the hurricane record thousands of years into the past. However, this approach also has its limitations. This dissertation addresses some of the limitations associated with geologic proxies used to reconstruct hurricane landfalls in the absence of historic data and tests new proxies for the identification of hurricane-derived overwash deposits. Modern storm deposits from two sites on the northern Gulf of Mexico coast are analyzed in detail …

Atomic Force Microscopy Tip-Enhanced Laser Ablation, Fan Cao

LSU Doctoral Dissertations

In the present work, an apertureless atomic force microscope (AFM) tip-enhanced laser ablation (TELA) system was developed and investigated. An AFM was coupled to an optical parametric oscillator (OPO) wavelength tunable laser for sample ablation with a submicron sampling size. The AFM was used to image the surface and hold the AFM tip 10 nm above the sample surface. The AFM tip is coated with a layer of gold with a thickness of 35 nm. The incident laser wavelength was tuned in the visible and near-infrared (IR) region and focused on the AFM tip. With the tip-enhancement effect, ablation craters …

Photo-Induced Remote C-H Functionalization And New Thioglycoside Donor Development For O-Glycosylation, Shaofu Du

LSU Doctoral Dissertations

This dissertation focuses on the method development of C-H functionalization using photo-redox catalysis and the synthesis of new thioglycoside donors towards O-glycosylation. Chapter 1 describes the remote Csp³-H functionalization using photo-redox catalysis. The site-selective and high-yielding conversion of unreactive aliphatic C-H bonds has been a challenge for organic chemists for many years. In this work, inert C-H bonds were successfully converted to more useful C-C, C-N, and C-O bonds via hydrogen atom transfer (HAT), radical translocation and polar crossover. This mechanistic manifold was enacted by visible-light irradiation of o-diazoniaphenyl alkyl sulfones in the presence of Ru(bpy) …

Toward The Impact Of Particulate Matter On Human Health: Evaluation Of Fluorescent Environmentally Persistent Free Radical (Epfr) Surrogates, Ansonia Badgett

LSU Doctoral Dissertations

Environmentally persistent free radicals (EPFRs)—a newly discovered pollutant associated with particulate matter (PM)—form during combustion and thermal processes, such as the incineration of hazardous waste. Various chlorine- and hydroxy-substituted benzenes chemisorb on the surface of metal oxides (e.g., NiO, CuO, and Fe₂O₃) and then form EPFRs, stabilized radical species, as the result of the transfer of electrons between the adsorbate and the metal ion of the metal oxide. Previous studies have shown direct correlations between ultra-fine (d < 0.1 mm) particulate matter (PM_0.1) exposure and adverse pulmonary health effects. PM_0.1 has the potential …

Singularity Resolution In Anisotropic And Black Hole Spacetimes In Loop Quantum Cosmology, Sahil Saini

LSU Doctoral Dissertations

Loop quantum cosmology (LQC) has in recent years led to successful resolution of singularities in cosmological models while agreeing with general relativity in low curvature limit. Existence of a bounce and the possibility of an effective continuum description closely approximating the quantum evolution have been notable features of this singularity resolution. The effective spacetimes of loop quantized isotropic and Bianchi-I models have been shown to be geodesically complete and free from strong singularities. In this dissertation, we extend these results to effective loop quantized Bianchi-II, Bianchi-IX and Kantowski--Sachs models with arbitrary minimally coupled matter, and also explore the possibility of …

Using Deep Learning To Forecast Spatiotemporal Crime Patterns, Shuzhan Fan

LSU Doctoral Dissertations

The distributional patterns of crime occurrences are closely related to their spatial, temporal, and environmental contexts. It has been a hot topic for researchers and crime analysts to discover such complex relationships in order to forecast crime, both spatially and temporally. Many factors play a role in the occurrences of crimes. Conventional crime forecasting research has primarily relied on historical crime records and socioeconomic data, while ignoring the rich social media and other environmental context data. The large volume of data requires a more appropriate forecasting framework with the ability to take in massive multimodal data and possibly achieve better …

The Effects Of Pressure And Magnetic Field On Phase Transitions And Related Physical Properties In Solid State Caloric Materials, Ahmad Ikhwan Us Saleheen

LSU Doctoral Dissertations

Solid-state caloric effects, such as the magnetocaloric (MCE) and barocaloric (BCE) effects, may be utilized in future cooling technologies that are more efficient and environment-friendly. Large caloric effects often occur near phase transitions, especially near coupled first-order magnetostructural transitions (MST), and are initiated by external parameters, such as magnetic field or hydrostatic pressure. In this dissertation, the effects of pressure, temperature, and magnetic field on the phase transitions in three material systems are studied in order to elucidate how the respective caloric effects are affected.

In the first study, the realization of a coupled MST in a MnNiSi-based system through …

Molecular Level Interactions And Transformations Of Natural Organic Matter Within The Environment, Benjamin J. Haywood

LSU Doctoral Dissertations

This work was done in order to deepen the understanding of interactions occurring during sorption of anthropogenic organic compounds and dissolved organic matter (DOM) onto soil. As well as the transformation DOM undergoes during the sorption process and the overall transformation OM undergoes in the environment. This was achieved through the use of a “bottom-up” synthetic investigation, “top-down” natural system study, and a combination of these approaches.

The “bottom-up” approach, discussed in Chapter 2, involved the synthesis of a modular multi-tiered engineered soil surrogate (ESS) designed to mimic OM and general trends identified in the literature that impacts sorption behavior. …

Calculation Guided Rational Design And Synthesis Of Novel Cationic Fluorescent Meso–Pyridinium Bodipys For Bio-Imaging, Daniel J. Lamaster

LSU Doctoral Dissertations

Chapter 1 contains a brief overview of the history, synthesis, and properties of BODIPY dyes as well as that of the biomedical applications of bio-imaging and photodynamic therapy. Additionally, an overview of the theoretical framework of density functional theory and its time-dependent variant are provided. In Chapter 2, the effects of structural modification on the electronic structure and electron dynamics of cationic meso-(4-pyridyl)-BODIPYs were investigated. A library of 2,6-difunctionalized meso-(4-pyridyl)-BODIPYs bearing various electron-withdrawing substituents was designed and DFT calculations were used to model the redox properties, while TDDFT was used to determine the effects of functionalization on the excited …

Beam Theory For Classical And Quantum Nonlinear Optics---Exposing Classical And Quantum Correlations Of Transverse-Spatial Modes, Robert Nicholas Lanning

LSU Doctoral Dissertations

Optics is arguably the most important branch of physics that has ever been studied. It is not only an essential ingredient of many other branches of physics that we study, it governs how we see, how we measure, and how we communicate in the modern world. And as the world continues to change, so do our tools and resources. In a relatively short amount of time, we have progressed from rudimentary tools that shape the world around us, to tools that harness the fundamental laws of nature. Unsurprisingly, the laws of nature governing optics remain paramount. This is because many …

Tidal-, Wind-, And Buoyancy-Driven Dynamics In The Barataria Estuary And Its Impact On Estuarine-Shelf Exchange Processes, Linlin Cui

LSU Doctoral Dissertations

A three-dimensional, high-resolution, Finite-Volume Coastal Ocean Model (FVCOM) was used to study the dynamics of Barataria Estuary located in the Southeastern Louisiana. Three numerical experiments with different discharge scenarios, including the actual discharge (average ~ 160 m³ s^-1) from the Davis Pond Diversion (DPD) over three months from April to June 2010, no discharge (NO), and the proposed Mid-Barataria Diversion (MBD) with a constant discharge of 850 m³ s^-1, were conducted to investigate the impacts of river diversions on salinity gradients and residence times in the estuary. The three-month average salinity indicated that surface …