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Articles 2431 - 2460 of 3417
Full-Text Articles in Physical Sciences and Mathematics
Bottom Boundary Layer Physics And Sediment Transport Along A Transgressive Sand Body, Ship Shoal, South-Central Louisiana: Implications For Fluvial Sediments And Winter Storms, Daijiro Kobashi
LSU Doctoral Dissertations
Ship Shoal, a shore-parallel sand body, was recently recognized as having a unique physical and biological environment and also as a potential sand resource for coastal restoration in coastal Louisiana. Little is known regarding such dynamics, in concert with fluvial sediments and winter storms, influenced in unique ecosystems, and likely in future potential sand mining. This dissertation addresses such the morphodynamics and sedimentary processes and their implications for the mining from the shoal using field measurements and numerical modeling studies. During the winter-spring season, fluvial sediment plumes shifted from the prevailing west to southeast during the post-frontal phases, resulted in …
Peptide Targeting Of Platinum Anti-Cancer Drug And Synthesis Of Water Soluble Monofunctional Pt(Ii) Complexes Useful For Biological Labeling, Margaret W. Ndinguri
Peptide Targeting Of Platinum Anti-Cancer Drug And Synthesis Of Water Soluble Monofunctional Pt(Ii) Complexes Useful For Biological Labeling, Margaret W. Ndinguri
LSU Doctoral Dissertations
Platinum has been used as an inorganic medicinal agent with various applications such as anti cancer agents. Several new targeted Pt(II) conjugates were synthesized having the NGR and LHRH targeting motif. The platinum conjugates bearing the NGR motif revealed selective delivery and destruction of cancer cells that had CD13 receptors compared to untargeted carboplatin drug. The development of targeted chemotherapeutic has opened a new approach for efficient delivery of antitumor toxins with minimal exposure to normal cells. Several peptide sequences are known to have the ability to target tumors, for instance NGR motif which home specifically in solid tumors and …
On-Line Laser Desorption/Ionization Mass Spectrometry, Damien A. Narcisse
On-Line Laser Desorption/Ionization Mass Spectrometry, Damien A. Narcisse
LSU Doctoral Dissertations
Interfaces for on-line laser desorption/ionization mass spectrometry are presented in this dissertation. An on line laser desorption interface allows samples to be introduced directly into the mass spectrometer for high-throughput applications. For this research, a linear time of flight mass spectrometer was constructed with an ionization source designed to accept various laser desorption interfaces. A ball inlet interface was used for continuous analyte deposition at atmospheric pressure and vacuum ionization. A solvent-based cleaning system and a separate capillary for MALDI matrix delivery was utilized for continuous on line sampling with the ball inlet interface. Microfluidic devices were brought into contact …
Algorithms Related To Subgroups Of The Modular Group, Constantin Cristian Caranica
Algorithms Related To Subgroups Of The Modular Group, Constantin Cristian Caranica
LSU Doctoral Dissertations
Classifying subgroups of the modular group PSL_2{Z} is a fundamental problem with applications to modular forms, in addition to its group-theoretic interest. While a lot of research has been done on the congruence subgroups of PSL_2{Z}, very little is known about noncongruence subgroups. The purpose of this thesis is to find and characterize small-index noncongruence subgroups of the modular group PSL_2{Z}. We use the concept of Farey symbol to describe the subgroups of PSL_2{Z}. The first part contains results concerning the geometry of subgroups of PSL_2{Z}. The second part describes a graph-theoretical approach to finding all subgroups of a given …
Unavoidable Minors In Graphs And Matroids, Carolyn Barlow Chun
Unavoidable Minors In Graphs And Matroids, Carolyn Barlow Chun
LSU Doctoral Dissertations
It is well known that every sufficiently large connected graph G has either a vertex of high degree or a long path. If we require G to be more highly connected, then we ensure the presence of more highly structured minors. In particular, for all positive integers k, every 2-connected graph G has a series minor isomorphic to a k-edge cycle or K_{2,k}. In 1993, Oxley, Oporowski, and Thomas extended this result to 3- and internally 4-connected graphs identifying all unavoidable series minors of these classes. Loosely speaking, a series minor allows for arbitrary edge deletions but only allows edges …
Global Positioning System In Curved Space-Time And Other Applications Of General Relativity, Argenis Daniel Da Silva
Global Positioning System In Curved Space-Time And Other Applications Of General Relativity, Argenis Daniel Da Silva
LSU Doctoral Dissertations
In this work, we present some applications of the theory of General Relativity. First, we show a numerical scheme to account for relativistic effects in the Global Positioning System. Then, a couple of applications of astrophysical interest are worked out. These are the study of the gravitational collapse of stars and the dynamical evolution of a three-dimensional Einstein-Klein-Gordon field.
Miocene Herpetofaunas From The Central Gulf Coast Usa: Their Paleoecology, Biogeography, And Biostratigraphy, Michael John Williams
Miocene Herpetofaunas From The Central Gulf Coast Usa: Their Paleoecology, Biogeography, And Biostratigraphy, Michael John Williams
LSU Doctoral Dissertations
The late Barstovian Fort Polk herpetofauna represents the most diverse herpetofauna on the Gulf Coast, USA, and includes 15 genera from ten families. The herpetofaunal composition of Fort Polk and Miocene east Texas localities is similar enough to Great Plains localities that they are all considered to be one biogeographical province during the Barstovian. The use of ternary diagrams, ratios of herpetological elements to kg matrix screened, and natricine-colubrine indices, has allowed determining the wetness of the Fort Polk sites. Development of a composite stratigraphic section for North American fossil snakes has allowed recognition of two extinctions of fossil snakes …
Size Controlled Metal Oxide Nanoparticles:Synthesis, Characterization, And Application To Catalysis, Hongyi Wu
Size Controlled Metal Oxide Nanoparticles:Synthesis, Characterization, And Application To Catalysis, Hongyi Wu
LSU Doctoral Dissertations
The research in this dissertation focuses on the synthesis of size-controlled metal oxide nanoclusters (< 10 nm) on amorphous silica and their catalytic performance in thermal degradation of chlorinated benzenes with regard to the cluster size effect. Furthermore, with the concern that metal can condense as the nano-size nuclei core for particle growth in combustion process, a flow reactor was built to investigate the effect of metal oxide nanoparticles on the formation of soot in fuel-rich combustion. The synthesis of copper oxide nanoclusters was carried by calcination of silica impregnated with dendrimer-metal complexes. The 4th generation poly(propylene imine) dendrimer DAB-Am32 was used in this template-based method. The sizes of copper oxide nanoclusters were exquisitely controlled in the range of 1-5 nm with narrow size distribution by changing the stoichiometric ratio of metal ion to the terminal primary amines of dendrimer, the equivalent metal oxide loading on surface, and the impregnation procedure. XANES and XPS studies revealed that CuO was the dominant component of copper oxide nanoclusters. This method was also experimentally proven to be valid in the preparation of other metal oxide nanoparticles, e.g., Ni and Fe, and with other oxide substrates, e.g., titanium oxide. Chlorinated benzenes were selected as the model compound for studying the activity of metal (Cu and Fe) oxide catalysts with regard to their cluster sizes. Compared to the surrogate of coarse metal oxide samples, which was prepared by incipient wetness method, their nanosize analogues showed superior catalytic activity on the conversion of chlorinated benzenes under both pyrolytic and oxidative thermal condition. Furthermore, such catalytic size effect was also observed on the selectivity of products yields. Sooting combustion was performed using a two-zone flow reactor with precise control on experimental parameters. Gas suspended metal oxide nanoparticles were generated by burning off the organic backbone of the dendrimer-metal complexes in zone 1 and immediately transferred to zone 2, where the hydrocarbon combustion occurred. TEM results of the particulate sample collected at the outlet of reactor indicated that metal oxide nanoparticles promoted soot formation. GC/MS analysis of the extracted organic materials from soot samples suggested the formation of PAH was also promoted by metal addition as well.
Stochastic Navier-Stokes Equations With Fractional Brownian Motions, Liqun Fang
Stochastic Navier-Stokes Equations With Fractional Brownian Motions, Liqun Fang
LSU Doctoral Dissertations
The aim of this dissertation is to study stochastic Navier-Stokes equations with a fractional Brownian motion noise. The second chapter will introduce the background results on fractional Brownian motions and some of their properties. The third chapter will focus on the Stokes operator and the semigroup generated by this operator. The Navier-Stokes equations and the evolution equation setup will be described in the next chapter. The main goal is to prove the existence and uniqueness of solutions for the stochastic Navier-Stokes equations with a fractional Brownian motion noise under suitable conditions. The proof is given with full details for two …
Barrier Island Migration Over A Consolidating Substrate, Julie Dean Rosati
Barrier Island Migration Over A Consolidating Substrate, Julie Dean Rosati
LSU Doctoral Dissertations
Barrier islands that overlie a compressible substrate load and consolidate the underlying subsurface. Through time, the elevation and aerial extent of these islands are reduced, making them more susceptible to inundation and overwash. Sand washed over the island and onto back-barrier marsh or into the bay or estuary begins the consolidation process on a previously non-loaded substrate, with time-dependent consolidation a function of the magnitude of the load, duration of load, and characteristics of the substrate. The result is an increase in the overwash, migration, breaching, and segmentation of these islands. This research determined the degree to which consolidation affects …
Single-Molecule Detection Of Unique Genome Signatures: Applications In Molecular Diagnostics And Homeland Security, Jason M. Emory
Single-Molecule Detection Of Unique Genome Signatures: Applications In Molecular Diagnostics And Homeland Security, Jason M. Emory
LSU Doctoral Dissertations
Single-molecule detection (SMD) offers an attractive approach for identifying the presence of certain markers that can be used for in vitro molecular diagnostics in a near real-time format. The ability to eliminate sample processing steps afforded by the ultra-high sensitivity associated with SMD yields an increased sampling pipeline. When SMD and microfluidics are used in conjunction with nucleic acid-based assays such as the ligase detection reaction coupled with single-pair fluorescent resonance energy transfer (LDR-spFRET), complete molecular profiling and screening of certain cancers, pathogenic bacteria, and other biomarkers becomes possible at remarkable speeds and sensitivities with high specificity. The merging of …
Impulsive Control Systems, Wei Cai
Impulsive Control Systems, Wei Cai
LSU Doctoral Dissertations
Impulsive control systems arose from classical control systems described by differential equations where the control functions could be unbounded. Passing to the limit of trajectories whose velocities are changing very rapidly leads to the state vector to "jump", or exhibit impulsive behavior. The mathematical model in this thesis uses a differential inclusion and a measure-driven control, and it becomes possible to deal with the discontinuity of movements happening over a small interval. We adopt the formulism of impulsive systems in which the velocities are decomposed by the slow and fast ones. The fast time velocity is expressed as the multiplication …
Function Spaces, Wavelets And Representation Theory, Jens Gerlach Christensen
Function Spaces, Wavelets And Representation Theory, Jens Gerlach Christensen
LSU Doctoral Dissertations
This dissertation is concerned with the interplay between the theory of Banach spaces and representations of groups. The wavelet transform has proven to be a useful tool in characterizing and constructing Banach spaces, and we investigate a generalization of an already known technique due to H.G. Feichtinger and K. Gröchenig. This generalization is presented in Chapter 3, and in Chapters 4 and 5 we present examples of spaces which can be described using the theory. The first example clears up a question regarding a wavelet characterization of Bergman spaces related to a non-integrable representation. The second example is a wavelet …
Iron Mediated Pecipitation Of Phenol: Protein Aggregates From Sugar Cane Juice, Lee R. Madsen Ii
Iron Mediated Pecipitation Of Phenol: Protein Aggregates From Sugar Cane Juice, Lee R. Madsen Ii
LSU Doctoral Dissertations
The Louisiana cane sugar industry is moving toward a vertically integrated arrangement where raw sugar producers will have an interest in refining. In the sugar refining process, raw sugar is affined to remove ~50 % of the color. The new refinery that will be built in Louisiana, however, will not include affining stations. To reduce costs of refining, either affining stations will need to be installed at each mill or new technologies that provide equivalent color reduction (~50% or ~750 IU) need to be implemented. As part of this dissertation a new technology for color reduction at raw sugar mills …
A Discrete Model Of Guided Modes And Anomalous Scattering In Periodic Structures, Natalia Grigoryevna Ptitsyna
A Discrete Model Of Guided Modes And Anomalous Scattering In Periodic Structures, Natalia Grigoryevna Ptitsyna
LSU Doctoral Dissertations
We study a discrete prototype of anomalous scattering associated with the interaction of guided modes of a periodic scatterer and plane waves incident upon the scatterer. The transmission anomalies arise because of the non-robustness of a guided mode, a mode that exists only at a specific frequency and wave number pair. The simplicity of the discrete prototype allows one to make certain explicit calculations and proofs, and to examine details of important resonant phenomena of the open wave guides. The main results are (1) a formula for transmission anomalies near a non-robust guided mode with rigorous error estimates that extends …
Assessing Linkages Between Petroleum Platforms And Pelagic Fishes Using Telemetry With Emphasis On Blue Runner (Caranx Crysos), Harmon Brown
Assessing Linkages Between Petroleum Platforms And Pelagic Fishes Using Telemetry With Emphasis On Blue Runner (Caranx Crysos), Harmon Brown
LSU Doctoral Dissertations
Petroleum platforms number greater than 4,200 in the Gulf of Mexico and Caranx crysos (blue runner) is one of the most abundant fish species around these platforms. Forty-six blue runner were tagged with acoustical transmitters in August 2005, though the study was terminated prematurely due to the impending arrival of Hurricane Katrina. Nineteen blue runner were tagged in September 2006 and tracked for up to two months. Blue runner exhibited limited site fidelity around the platforms in 2005. The home range of twenty-three blue runner was calculated in 2005. A significant difference was found between the fork length of the …
Phytochemical Analyses Of Bioactive Compounds In The Roots Of Cassia Alata Linn And The Anti-Angiogenic Evaluation Of Rhein As A Therapeutic Agent Against Breast Cancer Cells, Vivian Esther Fernand
Phytochemical Analyses Of Bioactive Compounds In The Roots Of Cassia Alata Linn And The Anti-Angiogenic Evaluation Of Rhein As A Therapeutic Agent Against Breast Cancer Cells, Vivian Esther Fernand
LSU Doctoral Dissertations
The research presented in this dissertation includes the novel phytochemical analysis of root extracts of Cassia alata L. and the anti-angiogenic evaluation of rhein in the treatment of breast cancer. To conduct these studies a combination of analytical techniques were employed, namely, chromatographic, spectroscopic, and bioanalytical. The first part of this research is focused on the phytochemical analysis of C. alata root extracts. A high performance liquid chromatography method was developed and validated for the determination of six phenolic compounds in the root extracts. The investigated compounds were identified by their ultraviolet spectra. Additionally, the presence of these phenolics was …
Studies On The Effect Of Natural Organic Matter And Hydration On The Sorption And Desorption Of Trifluorinated Pesticides, Charisma Vinarao Lattao
Studies On The Effect Of Natural Organic Matter And Hydration On The Sorption And Desorption Of Trifluorinated Pesticides, Charisma Vinarao Lattao
LSU Doctoral Dissertations
This work was done in order to deepen our molecular level understanding of how soil organic matter (SOM) is assembled in a whole soil and to provide further insight on the effect of SOM assembly on the uptake and release of hydrophobic organic compounds. Various techniques, including ultraviolet absorbance, fluorescence, and total carbon analysis, demonstrate that hydration/solvation of SOM is kinetically controlled. Initial wetting of a soil releases the hydrophobic moieties that are located at the outer surface of SOM, and longer wetting times exfoliate more hydrophobic quinone type moieties that are present in the middle layer, which in turn …
Methods And Design Issues For Next Generation Network-Aware Applications, Andrei Hutanu
Methods And Design Issues For Next Generation Network-Aware Applications, Andrei Hutanu
LSU Doctoral Dissertations
Networks are becoming an essential component of modern cyberinfrastructure and this work describes methods of designing distributed applications for high-speed networks to improve application scalability, performance and capabilities. As the amount of data generated by scientific applications continues to grow, to be able to handle and process it, applications should be designed to use parallel, distributed resources and high-speed networks. For scalable application design developers should move away from the current component-based approach and implement instead an integrated, non-layered architecture where applications can use specialized low-level interfaces. The main focus of this research is on interactive, collaborative visualization of large …
A Regularization Technique In Dynamic Optimization, Alvaro Guevara
A Regularization Technique In Dynamic Optimization, Alvaro Guevara
LSU Doctoral Dissertations
In this dissertation we discuss certain aspects of a parametric regularization technique which is based on recent work by R. Goebel. For proper, lower semicontinuous, and convex functions, this regularization is self-dual with respect to convex conjugation, and a simple extension of this smoothing exhibits the same feature when applied to proper, closed, and saddle functions. In Chapter 1 we give a introduction to convex and saddle function theory, which includes new results on the convergence of saddle function values that were not previously available in the form presented. In Chapter 2, we define the regularization and extend some of …
Merged Electrospray Ionization Mass Spectrometry, Jianan Dong
Merged Electrospray Ionization Mass Spectrometry, Jianan Dong
LSU Doctoral Dissertations
Ambient ionization allows the analysis of materials in their native environment without sample preparation by creating ions outside the mass spectrometer. The goal of this research was to develop new ambient ionization techniques for application to solids, liquids and particles under ambient conditions. Samples to be analyzed were directly merged with an electrospray of droplets, and then ionized and detected by a mass spectrometer. An ion trap mass spectrometer was modified with a nanoelectrospray source and configured for three experiments: merged electrospray ionization of dry particles, merged electrospray ionization of combustion products, and infrared laser desorption/ablation using electrospray for post-ionization. …
General Equilibrium Asset Pricing Under Regime Switching, Robert J Elliott, Hong Miao, Jin Yu
General Equilibrium Asset Pricing Under Regime Switching, Robert J Elliott, Hong Miao, Jin Yu
Communications on Stochastic Analysis
No abstract provided.
A Decomposition Of Multiple Wiener Integrals By The Lévy Process And Lévy Laplacian, Atsushi Ishikawa
A Decomposition Of Multiple Wiener Integrals By The Lévy Process And Lévy Laplacian, Atsushi Ishikawa
Communications on Stochastic Analysis
No abstract provided.
Errata: Existence And Uniqueness Of Solutions To The Backward Stochastic Lorenz System (Cosa, Vol. 1, No. 3 (2007) 473–483) [Mr2403863], P Sundar, Hong Yin
Errata: Existence And Uniqueness Of Solutions To The Backward Stochastic Lorenz System (Cosa, Vol. 1, No. 3 (2007) 473–483) [Mr2403863], P Sundar, Hong Yin
Communications on Stochastic Analysis
No abstract provided.
Limits Of Bifractional Brownian Noises, Makoto Maejima, Ciprian A Tudor
Limits Of Bifractional Brownian Noises, Makoto Maejima, Ciprian A Tudor
Communications on Stochastic Analysis
No abstract provided.
A Class Of Extreme X-Harmonic Functions, John Verzani
A Class Of Extreme X-Harmonic Functions, John Verzani
Communications on Stochastic Analysis
No abstract provided.
Applicability Of Multiplicative Renormalization Method For A Certain Function, Izumi Kubo, Hui-Hsiung Kuo, Suat Namli
Applicability Of Multiplicative Renormalization Method For A Certain Function, Izumi Kubo, Hui-Hsiung Kuo, Suat Namli
Communications on Stochastic Analysis
No abstract provided.
An Extension Of The Itô Integral, Wided Ayed, Hui-Hsiung Kuo
An Extension Of The Itô Integral, Wided Ayed, Hui-Hsiung Kuo
Communications on Stochastic Analysis
No abstract provided.
Locally Integrable Processes With Respect To Locally Additive Summable Processes, Oana Mocioalca
Locally Integrable Processes With Respect To Locally Additive Summable Processes, Oana Mocioalca
Communications on Stochastic Analysis
No abstract provided.