Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Mathematics (744)
- Chemistry (580)
- Analysis (564)
- Other Mathematics (556)
- Environmental Sciences (499)
-
- Earth Sciences (372)
- Oceanography and Atmospheric Sciences and Meteorology (342)
- Computer Sciences (243)
- Applied Mathematics (225)
- Physics (134)
- Oceanography (105)
- Geology (103)
- Astrophysics and Astronomy (79)
- Life Sciences (72)
- Engineering (71)
- Analytical Chemistry (34)
- Natural Resources and Conservation (33)
- Hydrology (32)
- Sedimentology (31)
- Geophysics and Seismology (29)
- Quantum Physics (28)
- Statistics and Probability (28)
- Other Physics (27)
- Physical Chemistry (26)
- Geochemistry (25)
- Geomorphology (25)
- Organic Chemistry (25)
- Ecology and Evolutionary Biology (24)
- Medicine and Health Sciences (24)
- Keyword
-
- Louisiana (58)
- Gulf of Mexico (36)
- Geology (22)
- Mississippi River (22)
- Wetlands (21)
-
- Analytical chemistry (20)
- Geochemistry (20)
- Organic chemistry (20)
- Synthesis (20)
- Machine learning (19)
- Microfluidics (17)
- Nanoparticles (17)
- Nitrogen (17)
- Antarctica (16)
- Hypoxia (16)
- Salinity (16)
- Estuary (15)
- Gravitational waves (14)
- Habitat (14)
- Hydrology (14)
- Modeling (14)
- Palynology (14)
- Stable isotopes (14)
- Climate change (13)
- Eutrophication (13)
- Mass spectrometry (13)
- Molecular dynamics (13)
- Phosphorus (13)
- Restoration (13)
- Barataria Bay (12)
- Publication Year
- Publication
- Publication Type
Articles 691 - 720 of 3417
Full-Text Articles in Physical Sciences and Mathematics
Transitional Granulite-Facies Mafic Xenoliths In The 2.8 Ga Trondjhemite-Tonalite-Granodiorite (Ttg) Gneisses Of The Eastern Beartooth Mountains, Mt/Wy: Evidence For Variable Fluid Interactions, Andrew W. Osborne
Honors Theses
No abstract provided.
Hinge Region In Dna Packaging Terminase Pul15 Of Herpes Simplex Virus: A Potential Allosteric Target For Antiviral Drugs, Lana Faisal Thaljeh
Hinge Region In Dna Packaging Terminase Pul15 Of Herpes Simplex Virus: A Potential Allosteric Target For Antiviral Drugs, Lana Faisal Thaljeh
Honors Theses
No abstract provided.
Effects Of Oil And Gas Development On Waterfowl Nesting Ecology In The Bakken Formation Of North Dakota, Cassandra G. Skaggs
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
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
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
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 …
Suspended Sediment Transport Revealed By Patterns In Turbidity And Electrical Conductivity Curves In Three Cave Systems In Missouri, Usa., Caroline M. Mierzejewski
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 …
Reflection Positivity: A Quantum Field Theory Connection, Joseph W. Grenier
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 …
Mosquito Image Classification Using Convolutional Neural Networks, Sumanth Vissamsetty
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
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. …
Environmental Controls On Dissolved Carbon Export And River Geochemistry - A Case Study In The Mississippi-Atchafalaya System, Jeremy Reiman
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
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 …
Climatology, Variability, And Return Periods Of Tropical Cyclone Strikes In The Northeastern And Central Pacific Basins, Nicholas S. Grondin
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 …
Surface Gravity Waves In The Gulf Of Mexico And Their Role In Ocean-Atmosphere Coupling, Ehsan Abolfazli
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 …
Infrared Laser Ablation For Biomolecule Sampling, Kelin Wang
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
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 …
Vulnerability Of Industrial Facilities In The Lower Mississippi River Industrial Corridor To Relative Sea Level Rise And Tropical Cyclone Storm Surge, Joseph Blake Harris
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 …
Cationic Cobalt (Ii) Hydroformylation, Drew Michael Hood
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
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. …
Precision Of Parameter Estimation In Quantum Metrology, Chenglong You
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
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 PM2.5and Total Suspended Particle (TSP) …
Optimization Of Quantum Optical Metrology Systems, Nicholas Michael Studer
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 …
Deltaic Wetland Dynamics From Seasonal To Centennial Scales, Giancarlo A. Restreppo
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, …
Determination Of Conversion Factors For Various Calibration Geometries Using Barium-133 In A Silver Zeolite Cartridge, Amin Hamideh
Determination Of Conversion Factors For Various Calibration Geometries Using Barium-133 In A Silver Zeolite Cartridge, Amin Hamideh
LSU Master's Theses
Iodine-131 (I-131) is a major fission product among other radionuclides released during a nuclear incident. This radioiodine has a half-life of 8.02 days and the primary organ of uptake through ingestion or inhalation is the thyroid gland. For these reasons, nuclear power plants must routinely monitor I-131 through air sampling. Currently, there are two adsorbing media to collect I-131: activated charcoal and silver zeolite cartridges. Silver zeolite cartridges are generally used during a post nuclear incident due to its affinity for iodine while not adsorbing noble gases such as krypton-85 and xenon-135. After an air sample is taken from a …
Investigating Cationic Metal Centers For Hydroformylation, Ryan Alexander Johnson
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 …
Reflector Dip Trends In Seismic Sh-Wave Imaging Of A Modern Lower Mississippi River Point Bar, Adam Gostic
Reflector Dip Trends In Seismic Sh-Wave Imaging Of A Modern Lower Mississippi River Point Bar, Adam Gostic
LSU Master's Theses
Various studies of ancient point bars have noted that a relationship can be observed between the dip angle and grain size of point bar lateral accretion deposits, with the most mud-rich deposits tending to exhibit the greatest dip. No analysis and only cursory explanations for this relationship have been provided. Additionally, buried mid-channel bars are absent from typical models of point bar architecture.
We successfully image the architecture of late-stage point bar deposits with a near surface 2D seismic SH-wave reflection survey and generate an SH-wave velocity model of the subsurface in the study area in order to interpret the …
Phase Estimation In Linear And Nonlinear Interferometers, Sushovit Adhikari
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, …
Multiplexed Paper Microfluidics For Titration And Detection Of Ingredients In Beverages, Manas Ranjan Gartia, Alisha Prasad
Multiplexed Paper Microfluidics For Titration And Detection Of Ingredients In Beverages, Manas Ranjan Gartia, Alisha Prasad
Faculty Publications
Food safety and access to systematic approaches for ensuring detection of food hazards is an important issue in most developing countries. With the arrival of paper-based analytical devices (mu PADs) as a promising, rapid, easy-to-use, and low-cost analytical tool, we demonstrated a simple microfluidic-based titration study for the analysis of packaged fruit juices. Similar, to the titration experiments using traditional glassware in chemistry laboratories, in this study the titration experiments were developed using paper microfluidics for the analysis of several analytes such as pH, vitamin C, sugars, and preservatives present in the packaged fruit juices. The allergen found commonly in …
On The Adjoint Markov Policies In Stochastic Differential Games, Nicolai V. Krylov
On The Adjoint Markov Policies In Stochastic Differential Games, Nicolai V. Krylov
Communications on Stochastic Analysis
No abstract provided.
A Nonlocal Approach To The Quantum Kolmogorov Backward Equation And Links To Noncommutative Geometry, Will Hicks
A Nonlocal Approach To The Quantum Kolmogorov Backward Equation And Links To Noncommutative Geometry, Will Hicks
Communications on Stochastic Analysis
No abstract provided.