Digital Commons Network^™

Spatiotemporal Variation Of Benthic Silica Fluxes In The Ngom Shelf, Byron Ebner

LSU Master's Theses

Dissolved silica (DSi), plays an important role in regulating primary productivity of silicifying organisms, such as diatoms which precipitate hard parts composed of biogenic silica (bSi) in coastal and shelf ecosystems fed by major rivers. In the Northern Gulf of Mexico (NGOM), loading of nitrogen and phosphorous have increased compared to a decline in DSi in the Mississippi River. Continued decreasing in DSi loading could lead to limited diatom growth and production or shifts in community composition, therefore, it is important understand the role of benthic fluxes in providing silica to the overlying water column as there are few regional …

Impacts Of Freight Consolidation And Truck Sharing On Freight Mobility, Tieming Liu, Chaoyue Zhao

Publications

The trucking industry is an important sector of the U.S. economy. However, it is quite fragmented, hindering the efficiency of cargo transportation and the ability for small carriers to identify demands to fill full truck loads. The focus of this research is to study models and algorithms in order to aid online freight marketplaces to identify efficient consolidation strategies. To accomplish this aim, a new mixed integer programming model for the pickup and delivery problem has been developed. The model is geared towards identifying effective freight consolidation opportunities. A branch-and-cut algorithm to solve the model was also developed. The model …

Effects Of Oil And Gas Development On Waterfowl Nesting Ecology In The Bakken Formation Of North Dakota, Cassandra G. Skaggs

LSU Master's Theses

The Prairie Pothole Region (PPR) is one of the most important areas on the continent for grassland-nesting birds. Thirty percent of the PPR overlaps the Bakken shale formation where rapidly accelerating oil and gas development has the potential to impact millions of breeding waterfowl. While oil and gas development has negatively affected other ground-nesting birds such as sagebrush passerines and Greater Sage-Grouse (Centrocercus urophasianus) in Wyoming, the potential impact on breeding waterfowl in the PPR is unknown. In addition, the PPR landscape is already heavily fragmented by agriculture, and increasing land conversion and disturbance from petroleum extraction may further …

Structure Beneath The Northern Los Angeles Basins From Teleseismic Receiver Functions, Guibao Liu

LSU Master's Theses

This thesis presents part of the work published in Liu et al. (2018).

The Los Angeles area is at high risk of seismic amplification due to its location on top of sedimentary basins. It is very important to obtain accurate information on the crustal structure, in particular, the basin structure of the northern basins, in order to estimate the resulting ground motion and earthquake hazards due to a large San Andreas fault earthquake. In the Liu et al. (2018) study, we image the crustal structure beneath the northern basins using a densely spaced, autonomous 3-component seismometer array in the urban …

Assessment And Correction Of Lidar-Derived Dems In The Coastal Marshes Of Louisiana, William M. Lauve

LSU Master's Theses

The onset of airborne light detection and ranging (lidar) has resulted in expansive, precise digital elevation models (DEMs). DEMs are essential for modeling complex systems, such as the coastal land margin of Louisiana. They are used for many applications (e.g. tide, storm surge, and ecological modeling) and by diverse groups (e.g. state and federal agencies, NGOs, and academia). However, in a marsh environment, it is difficult for airborne lidar to produce accurate bare-earth measurements and even accurate elevations are rarely verified by ground truth data. The accuracy of lidar in marshes is limited by the sensor’s resolution …

Sediment Transport And Channel Morphology Of A Natural And A Leveed Alluvial River, Bo Wang

LSU Master's Theses

Alluvial rivers are shaped by interactions of flow and sediment transport. Their lower reaches to the world’s oceans are highly dynamic, often presenting engineering and management challenges. This thesis research aimed to investigate channel dynamics and sediment transport in a natural river and a highly engineered river in South Louisiana, in order to gain much-needed science information for helping develop sustainable practices in river engineering, sediment management, and coastal restoration and protection. Especially, the thesis research examined (1) riverbed deformation from bank to bank in the final 500-km reach of the Mississippi River, (2) bed material transport at the Mississippi-Atchafalaya …

Strategies To Overcome Antagonism Of Quizalofop-P-Ethyl When Applied In Mixture With Other Herbicides, Lucas C. Webster

LSU Master's Theses

A field study was conducted in 2017 and 2018 at the LSU Agricultural Center H. Rouse Caffey Rice Research Station (RRS) near Crowley, LA. to evaluate the influence of different adjuvants in overcoming the antagonism of quizalofop when mixed with bispyribac in Louisiana rice production. The antagonism of quizalofop mixed with bispyribac plus HCOC at 14 DAIT was overcome with a neutral interaction observed at 28 DAIT for barnyardgrass control with an observed control of 91%, compared with an expected control of 97%. The addition of COC, SNS or HCOC into a mixture of quizalofop plus bispyribac provided synergistic or …

Suspended Sediment Transport Revealed By Patterns In Turbidity And Electrical Conductivity Curves In Three Cave Systems In Missouri, Usa., Caroline M. Mierzejewski

LSU Master's Theses

In cave streams, the movement of sediment as suspended and bed loads are linked to the occurrence of precipitation events on the surface. During precipitation events, the discharge of the streams in the basin increases. As those surface streams flow into cave streams via sinkholes or fissures, the discharge in cave streams increase. In addition to changes in discharge, the response of the surface and cave streams to precipitation include changes in turbidity and electrical conductivity of the stream water.

Changes in turbidity (Tu), electrical conductivity (EC), and discharge (Q) of water in the cave stream can be used to …

Modeling Of Fluid Injection For Hydraulic Fracturing Initiation In Porous Rock Formations, Krishna Adhikari

LSU Master's Theses

Hydraulic fracturing has been widely opted in recent times to simulate the unconventional reservoirs and thus, has become key a subject of interest in petroleum engineering. The stress concentration around the borehole affects the breakdown pressure and fracture reopening pressure during the hydraulic fracturing treatments. Thus, the state of stress around borehole wall and its surrounding rocks due to instantaneous drilling and a fluid injection at borehole surface needs to be determined accurately to initiate the hydraulic fractures. This research intends to derive the analytical stress solution of inclined borehole subjected to time-dependent fluid injection and in-situ stress, verify the …

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 …

Self-Healing Composite Of Thermoset Polymer And Programmed Super Contraction Fibers, Guoqiang Li, Harper Meng

College of Engineering Patents

A composition comprising thermoset polymer, shape memory polymer to facilitate macro scale damage closure, and means for molecular scale healing has the ability to repair structural defects by a bio-mimetic, close-then-heal process. The shape memory polymer serves to bring surfaces of a structural defect into proximity, after which the healing means moves into the defect and provides molecular scale healing. The means for molecular scale healing can be a thermoplastic, such as fibers, particles or spheres, which are heated to or above the thermoplastic's melting point, and then the composition is cooled below that melting temperature. The compositions can not …

Mosquito Image Classification Using Convolutional Neural Networks, Sumanth Vissamsetty

LSU Master's Theses

Human life has always been affected by insects, especially mosquitoes, since it's early beginnings. This pesky insect acts as a vector that transmit pathogens through feeding on our blood, spreading life-threatening diseases like Zika Virus, Malaria, Dengue fever, Chikungunya and more. It is important to prevent these mosquitoes from harming humans and one way to do so is to control the mosquito population, or mosquito abatement as it is commonly known. It is important to note that not all mosquitoes are the same and each of them live, reproduce and attack in their own unique way. Hence it is crucial …

Exploring Geochemical Proxies For Identifying Cryptic Sequence Boundaries In The Geologic Past Using Modern Bahamian Analogues, Evan B. Magette

LSU Master's Theses

Previous studies of carbonate diagenesis have suggested that bulk Sr concentrations and inorganic δ¹³C values may be a useful proxy for identifying cryptic sequence boundaries in meteorically altered limestones due to geochemical processes associated with carbonate mineral stabilization in cement precipitation in the meteoric diagenetic environment. However, it is possible that natural geochemical variation in sediments may produce geochemical shift which could be misinterpreted as a cryptic sequence boundary. To test this, the Two Pines roadcut containing a previously identified protosol on Eleuthera, Bahamas, which has been affected by vadose meteoric diagenesis was sampled for bulk geochemical analysis. …

A Retrospective Analysis And Method Validation Of Postmortem Interval Estimation In Louisiana, Sophia Reck

LSU Master's Theses

Forensic anthropologists are often called upon to assess the postmortem interval (PMI; i.e. time since death) of remains in varying states of decomposition and skeletonization. These assessments rely on familiarity with general taphonomic sequences and processes, in addition to experience with how these processes present in local environments and conditions. Assessment using such qualitative methods is a subjective process. Therefore, some researchers have developed formulae whose purpose is to estimate PMI in an objective format. In these instances, the resultant PMI estimation formulae were developed using local data and therefore have the potential for local applicability. Additionally, for some regions, …

Chemical Durability And Dissolution Kinetics Of Iodoapatite In Aqueous Solutions, Zelong Zhang, William L. Ebert, Tiankai Yao, Jie Lian, Kalliat T. Valsaraj, Jianwei Wang

Faculty Publications

© 2019 American Chemical Society. Understanding the long-term release of radionuclides from nuclear waste to the environment is critical for public acceptance and sustainability of nuclear energy. Iodoapatite, a synthetic material similar to mineral vanadinite proposed for radioactive iodine-129 immobilization, is employed in this study as a model system for iodine waste forms and ceramic waste forms in general to understand its long-term chemical durability. Semidynamic leaching experiments were performed in cap-sealed Teflon vessels to evaluate the chemical durability at temperatures from 20 to 90 °C and pH values from 4 to 9 using deionized water and pH buffer solutions. …

Environmental Controls On Dissolved Carbon Export And River Geochemistry - A Case Study In The Mississippi-Atchafalaya System, Jeremy Reiman

LSU Master's Theses

Rivers serve as an important medium for the exchange of elements between land, ocean, and atmosphere. This thesis consists of three interconnected studies with the overarching goal of analyzing the environmental factors influencing dissolved carbon dynamics and river geochemistry in large rivers. These studies utilized river water samples and in-stream measurements collected from the Mississippi and Atchafalaya Rivers at hourly to monthly intervals between 2013 to 2018, along with ambient river and meteorological data downloaded from public-access databases. Results indicate substantially higher dissolved organic carbon concentrations (DOC, 611 ±181 µmol L^-1) but lower concentrations of dissolved inorganic carbon …

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 …

Flood Resilience Assessment Of New Orleans After Hurricane Katrina Based On Thermal And Vegetation Index Image Time Series, Yirui Deng

LSU Master's Theses

Resilience is a concept with increasing importance in modern risk management because of its role in reducing risks of unpreventable disasters. Previous resilience assessment studies often require extensive surveys of various social, economic, and psychological data or incorporate remote sensing data as one of the complicated physical and social parameters for assessment models. Limited data accessibility to such data due to funding, time, and labor intensity is a major challenge for their wider applications. Therefore, this study proposes the hypothesis that the overall resilience of an urban area to disturbances of natural disasters can be reflected through the time series …

Climatology, Variability, And Return Periods Of Tropical Cyclone Strikes In The Northeastern And Central Pacific Basins, Nicholas S. Grondin

LSU Master's Theses

Tropical cyclones (TCs) are among the most destructive meteorological phenomena and impact the lives of people who reside along the coast. The American Pacific Coastline borders the second most active TC development region in the world, the northeastern Pacific (NE Pac) basin. This region, along with the Central Pacific (C Pac)-bordering Hawaii is home to a growing population and cities engaged in a variety of economic activities, most prominently agriculture, fishing, and tourism. This study analyzes fifty-two (1966-2017) years of NE Pac and C Pac TCs through applying track data from the National Hurricane Center’s HURDAT2 and a TC size …

Evaluation Of Reproductive Phenology And Ecology Of Eastern Wild Turkey (Meleagris Gallopavo Silvestris) Across The Southeastern United States, Nicholas W. Bakner

LSU Master's Theses

Avian reproduction is known to be a driver of population dynamics across species and systems. Behavioral decisions during incubation such as habitat selection and nest attentiveness are thought to affect nest success. The incubation process is a costly period during which individuals are sedentary and must balance survival with reproductive success and overall fitness. Current understanding of Eastern wild turkey incubation behavior provides a limited view of the incubation period. Using GPS data collected from Eastern wild turkeys (n = 220), I evaluated nest fate as it relates to recess frequency, distance travelled during recess, and habitat selection during …

String Out And Compressibility Effect On Pressure Rise In A Shut-In Well, Nicholas Henry

LSU Master's Theses

Gas kick migration experiments were performed in a small-scale well prototype model of annular geometry to analyze the behavior of gas kicks in highly non-Newtonian fluids. The objective was to isolate and estimate the effects system compressibility and bubble string out have on the pressure build up in a situation in which a gas kick rises through a noncirculating drilling mud in a vertical well.

The experiments consisted of 2 tests. The first test measured the apparent compressibility of the liquid phase of the experiment – that phase which simulated the drilling mud in a gas kick situation. The second …

Surface Gravity Waves In The Gulf Of Mexico And Their Role In Ocean-Atmosphere Coupling, Ehsan Abolfazli

LSU Master's Theses

This study provides an overview of the surface gravity wave dynamics in the Gulf of Mexico (GoM) using numerical simulations. The focus is on the effects of ocean currents on waves, and the geographic distribution of a set of wave statistics and parameters related to the role of waves on both sides of the ocean-atmosphere interface. Simulations are performed using the Simulating WAves Nearshore (SWAN) model with and without coupling with the Regional Ocean Modeling System (ROMS) model within the Coupled Ocean Atmosphere Wave Sediment Transport (COAWST) framework. In the GoM, currents alter the climatological significant wave heights (H …

Effects Of A Repeated Writing Intervention On Writing Fluency And Writing Quality, Katherine L. Moore

LSU Master's Theses

Writing is a fundamental skill that is essential for students’ academic success. In fact, students with writing difficulties are shown to have lower academic achievement and reduced likelihood of college acceptance (Graham & Perin, 2007). Writing fluency is a crucial component in the development of writing abilities, as it allows for the development of higher-order writing skills (Bloom, 1986, Binder, Haughton & Bateman, 2002). Limited research exists of interventions targeted specially for writing fluency; however, performance feedback procedures have been shown as effective (Hier & Eckert, 2016). Literature suggests the skills of reading and writing share similar processes of learning …

Developing The 21st Century Musician: A Case Study Of Applied Tuba And Euphonium Studio Models At American Universities, Chasse Benjamin Duplantis

LSU Doctoral Dissertations

Musicians navigate an ever-changing career landscape that requires a strong set of ancillary skills in addition to their assumed musical mastery. A successful 21^stcentury career, musical or beyond, demands versatility and command of skills that may include communication, innovation, adaptability, and higher order thinking skills. This document explores the applied professor’s role in introducing the aforementioned elements as well as musical versatility, critical thinking, and skills in collaboration, pedagogy, research, entrepreneurship, and business. Finally, it will examine how or even if the combination of these skills affects student success. The reader will find interviews with successful tuba and …

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) …

Insights Into The Collaborative Process Between Electronic Music Composers And Commissioning Saxophonists, Taylor Barbay Assad

LSU Doctoral Dissertations

This monograph gives information about the collaborative process that takes place between commissioning saxophonists and composers of electronic music. It focuses specifically on music for solo performers and works for electronics, either with prerecorded tape or live electronics. The core of this paper centers on interviews conducted with composers of works for saxophone and electronics and professional saxophonists about the nature of their collaborations on new music for solo saxophone and electronics. The composers and performers selected had previously worked together on preparing and premiering a piece. Questions were developed for interviews of the composers and performers. The questions were …

Foucauldian Dynamics In The Formation Of A Fifth Grade Writing Culture, Ashley Renee Watson

LSU Doctoral Dissertations

This study looks at a student writing culture in a fifth grade English language arts classroom through the lens of Foucauldian power dynamics to examine the power relationships in the classroom and curriculum. The research questions were: 1) What is the nature of a writing culture in a fifth-grade writing classroom? 2) What are students’ perceptions of writing in a fifth grade ELA classroom? The methodology for the study was case study research.

The research took place during the 2017-2018 school year at Southeast Elementary School in Lancaster County in the southeastern part of the United States. Data was collected …

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 …

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 …