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Articles 2701 - 2730 of 3417

Full-Text Articles in Physical Sciences and Mathematics

The Use Of Stable Isotopes To Determine The Ratio Of Resident To Migrant King Rails In Southern Louisiana And Texas, Marie Perkins Jan 2007

The Use Of Stable Isotopes To Determine The Ratio Of Resident To Migrant King Rails In Southern Louisiana And Texas, Marie Perkins

LSU Master's Theses

Over the past 30 years, the king rail (Rallus elegans) has purportedly declined precipitously throughout its range, with the most severe declines seen in the migratory populations. King rails, however, are considered a game species in Louisiana and Texas, thus, it is important to determine what proportion of king rails wintering there are migratory. This is complicated because there is no reliable method to distinguish between king and clapper rails and few studies have attempted to capture wintering rails. The objectives of this study were to: 1) Determine the best method for capturing wintering rails; 2) Determine if morphometric measurements …

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Subrepresentation Semirings And An Analogue Of 6j-Symbols, Nam Hee Kwon Jan 2007

Subrepresentation Semirings And An Analogue Of 6j-Symbols, Nam Hee Kwon

LSU Doctoral Dissertations

Let G be a quasi simply reducible group, and let V be a representation of G over the complex numbers $mathbb{C}$. In this thesis, we introduce the twisted 6j-symbols over G which have their origin to Wigner's 6j-symbols over the group SU(2) to study the structure constants of the subrepresentation semiring S_{G}(End(V)), and we study the representation theory of a quasi simply reducible group G laying emphasis on our new G-module objects. We also investigate properties of our twisted 6j-symbols by establishing the link between the twisted 6j-symbols and Wigner's 3j-symbols over the group G.

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The Spectral And Photophysical Characterization Of Water Solubilizing Metal Phthalocyanines For Highly Sensitive Detection In Biological Studies, Vera Tamisha Verdree Jan 2007

The Spectral And Photophysical Characterization Of Water Solubilizing Metal Phthalocyanines For Highly Sensitive Detection In Biological Studies, Vera Tamisha Verdree

LSU Doctoral Dissertations

Efforts to improve the technology for DNA analyses stimulated the work presented here to develop a series of fluorescent probes that would aid in the increased multiplexing capabilities allowing the ability to detect multiple targets in a single measurement. Typically, spectral discrimination has been used to identify each DNA fragment in sequencing or diagnostic applications by means of unique emission properties from several labeling dyes. This has been accomplished with labels that fluoresce in the visible region. The limitations with these dyes is the broad emission profile making discrimination difficult, high intrinsic biological fluorescence and structural differences of the dyes …

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Knowledge-Based Methods For Automatic Extraction Of Domain-Specific Ontologies, Janardhana R. Punuru Jan 2007

Knowledge-Based Methods For Automatic Extraction Of Domain-Specific Ontologies, Janardhana R. Punuru

LSU Doctoral Dissertations

Semantic web technology aims at developing methodologies for representing large amount of knowledge in web accessible form. The semantics of knowledge should be easy to interpret and understand by computer programs, so that sharing and utilizing knowledge across the Web would be possible. Domain specific ontologies form the basis for knowledge representation in the semantic web. Research on automated development of ontologies from texts has become increasingly important because manual construction of ontologies is labor intensive and costly, and, at the same time, large amount of texts for individual domains is already available in electronic form. However, automatic extraction of …

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Backward Stochastic Navier-Stokes Equations In Two Dimensions, Hong Yin Jan 2007

Backward Stochastic Navier-Stokes Equations In Two Dimensions, Hong Yin

LSU Doctoral Dissertations

There are two parts in this dissertation. The backward stochastic Lorenz system is studied in the first part. Suitable a priori estimates for adapted solutions of the backward stochastic Lorenz system are obtained. The existence and uniqueness of solutions is shown by the use of suitable truncations and approximations. The continuity of the adapted solutions with respect to the terminal data is also established. The backward stochastic Navier-Stokes equations (BSNSEs, for short) corresponding to incompressible fluid flow in a bounded domain $G$ are studied in the second part. Suitable a priori estimates for adapted solutions of the BSNSEs are obtained …

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Computing And Analyzing Gravitational Radiation In Black Hole Simulations Using A New Multi-Block Approach To Numerical Relativity, Ernst Nils Dorband Jan 2007

Computing And Analyzing Gravitational Radiation In Black Hole Simulations Using A New Multi-Block Approach To Numerical Relativity, Ernst Nils Dorband

LSU Doctoral Dissertations

Numerical simulations of Kerr black holes are presented and the excitation of quasinormal modes is studied in detail. Issues concerning the extraction of gravitational waves from numerical space-times and analyzing them in a systematic way are discussed. A new multi-block infrastructure for solving first order symmetric hyperbolic time dependent partial differential equations is developed and implemented in a way that stability is guaranteed for arbitrary high order accurate numerical schemes. Multi-block methods make use of several coordinate patches to cover a computational domain. This provides efficient, flexible and very accurate numerical schemes. Using this code, three dimensional simulations of perturbed …

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Lanthanide Complexes As Fluorescent Indicators For Neutral Sugars And Cancer Biomarkers, Onur Alpturk Jan 2007

Lanthanide Complexes As Fluorescent Indicators For Neutral Sugars And Cancer Biomarkers, Onur Alpturk

LSU Doctoral Dissertations

Simple water soluble lanthanum and europium complexes are effective at detecting neutral sugars as well as glyco- and phospholipids. In solutions at physiologically relevant pH the fluorescent lanthanum complex binds neutral sugars with apparent binding constants comparable to those of arylboronic acids. Interference from commonly occurring anions is minimal. The europium complex detects sialic acid-containing gangliosides at pH 7.0 over an asialoganglioside. This selectivity is attributed, in large part, to the cooperative complexation of the oligosaccharide and sialic acid residues to the metal center, based on analogous prior studies. In MeOH, lysophosphatidic acid (LPA), a biomarker for several pathological conditions …

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Syntheseses [Sic] And Evaluation Of Porphyrin Derivatives For Applications In Medicine And In Material Science, Erhong Hao Jan 2007

Syntheseses [Sic] And Evaluation Of Porphyrin Derivatives For Applications In Medicine And In Material Science, Erhong Hao

LSU Doctoral Dissertations

Chapter 1 presents a concise introduction to porphyrins, especially on the synthesis of meso-tetraphenylporphyrins, which were synthesized during the course of my research and were used for further purposes in the following chapters. Chapter 2 describes the synthesis of a series of cobaltacarborane-porphyrin conjugates for the boron neutron capture therapy (BNCT) of tumors. Using an efficient and high yield ring-opening reaction, N-substituted porphyrins were also synthesized. The spectroscopic and structural properties of these compounds are presented. These high percentage boron and amphiphilic compounds are promising boron delivery agents for BNCT (prelimary cellular studies using some of these compounds have been …

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Wood Liquefaction In The Presence Of Phenol With A Weak Acid Catalyst And Its Potential For Novolac Type Wood Adhesives, Hui Pan Jan 2007

Wood Liquefaction In The Presence Of Phenol With A Weak Acid Catalyst And Its Potential For Novolac Type Wood Adhesives, Hui Pan

LSU Doctoral Dissertations

Wood liquefaction was conducted using phenol as a reagent solvent with oxalic acid as a catalyst. A series of studies were done on liquefied wood, liquefied wood residues, novolac-type liquefied wood resins, and bio-composites fabricated from liquefied wood resin. The results of the liquefied wood residue characterization revealed that the liquefaction reactions conducted in different reaction vessels underwent different liquefaction mechanisms. The crystallinity indexes of the liquefied wood residues were higher than that of the original wood, indicating that the amorphous lignin was the most susceptible component in wood to the liquefaction reaction. Fe2+ and Fe3+ ions were found to …

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Application-Specific Reliable Data Transfer In Wireless Sensor Networks, Damayanti Datta Jan 2007

Application-Specific Reliable Data Transfer In Wireless Sensor Networks, Damayanti Datta

LSU Doctoral Dissertations

A wireless sensor network (WSN) is a collection of sensor nodes and base stations connected via wireless medium. It sends data collected from the nodes to the base stations for generating information. The size and low cost of the sensor nodes as well as the WSN's ability to connect without wired links are its key advantages which enable it to be deployed in hostile or inaccessible environments at low cost. However, WSNs suffer from high data loss due to the inherent weaknesses in a wireless transmission medium, transmission problems in hostile environments due to human interference, etc. and node failures …

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Fabrication Of Dna Microarrays On Poly (Methylmethacrylate) Substrates For Biomolecular Reporting, Catherine N. Situma Jan 2007

Fabrication Of Dna Microarrays On Poly (Methylmethacrylate) Substrates For Biomolecular Reporting, Catherine N. Situma

LSU Doctoral Dissertations

DNA microarrays require the use of substrates with well-established surface modification / probe attachment chemistries. Glass/quartz have been widely adopted as typical support materials since their surface modification chemistries which involve the use of siloxane –based chemistries have been widely studied however; these chemistry is susceptible to hydrolytic cleavage especially at high or low pH values. Recently, polymers have been sought as alternative microarray support materials but their surface modification strategies are not well characterized compared to glass. This report will entail surface photo-modification of PMMA polymer substrates by UV irradiation which produces functional scaffolds of carboxylic groups that allow …

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Exploring The Quark-Gluon Content Of Hadrons: From Mesons To Nuclear Matters, Hrayr Hamlet Matevosyan Jan 2007

Exploring The Quark-Gluon Content Of Hadrons: From Mesons To Nuclear Matters, Hrayr Hamlet Matevosyan

LSU Doctoral Dissertations

Even though Quantum Chromodynamics (QCD) was formulated over three decades ago, it poses enormous challenges for describing the properties of hadrons from the underlying quark-gluon degrees of freedom. Moreover, the problem of describing the nuclear force from its quark-gluon origin is still open. While a direct solution of QCD to describe the hadrons and nuclear force is not possible at this time, we explore a variety of developed approaches ranging from phenomenology to first principle calculations at one or other level of approximation in linking the nuclear force to QCD. The Dyson Schwinger formulation (DSE) of coupled integral equations for …

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Exploring The Binding Of Amine And Sulfonamide Ligands In Rhenium(I) Tricarbonyl And Platinum(Ii) Complexes, Anna Maria Christoforou Jan 2007

Exploring The Binding Of Amine And Sulfonamide Ligands In Rhenium(I) Tricarbonyl And Platinum(Ii) Complexes, Anna Maria Christoforou

LSU Doctoral Dissertations

Platinum is the metal present in various classes of inorganic medicinal agents directed at important diseases such as cancer or viral infections. Several new Pt(II) complexes of polyamine ligands bearing a dansyl moiety linked by a sulfonamide group were prepared; in some cases the sulfonamide nitrogen formed a bond to Pt. The sulfonamido group donates strongly to Pt and places the dansyl group close to a vacant coordination position, allowing it to stack with bound guanine base (G) when G binds. The emission of the fluorophore decreases with decreasing distance to Pt. Metal nuclide radiopharmaceuticals contain a metal core and …

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Factors Influencing The Spatial Distribution Of Natural Resource-Based Industries: The Softwood Lumber Industry In The United States South, Francisco Xavier Aguilar Jan 2007

Factors Influencing The Spatial Distribution Of Natural Resource-Based Industries: The Softwood Lumber Industry In The United States South, Francisco Xavier Aguilar

LSU Doctoral Dissertations

Expanding on the Theory of Location, New Economic Geography, and Porter's Theory of Clusters this dissertation attempts to identify key factors influencing the location of firms in a resource-based industry. The softwood lumber industry in the United States is used as a case study to test several hypotheses concerning these theories. Two U.S. regions, the West and the South, were selected for analysis because they account for over 70 percent of U.S lumber manufacturing capacity. A multi-disciplinary research approach involved three-stages. First, self-reported preferences were analyzed using common factor and conjoint analyses for preferences for location attributes. Surveys were sent …

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Multiplicative Renormalization Method For Orthogonal Polynomials, Suat Namli Jan 2007

Multiplicative Renormalization Method For Orthogonal Polynomials, Suat Namli

LSU Doctoral Dissertations

To study the orthogonal polynomials, Asai, Kubo and Kuo recently have developed the multiplicative renormalization method. Motivated by infinite dimensional white noise analysis, it is an alternative to the computational part of the classical Gram-Schmidt process to find the orthogonal polynomials for a given measure. Instead of finding the orthogonal polynomials recursively as described in the Gram-Schmidt process, one analyzes different types of generating functions systematically in order to obtain polynomials after power series expansion. This work also produces the Jacobi-Szego parameters easily and paves the way for the study of one-mode interacting Fock spaces related to these parameters. They …

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Stereochemical And Regiochemical Trends In The Selective Spectrophotometric Detection Of Biological Molecules, Shan Jiang Jan 2007

Stereochemical And Regiochemical Trends In The Selective Spectrophotometric Detection Of Biological Molecules, Shan Jiang

LSU Doctoral Dissertations

Useful mechanistic studies to date concerning sugar detection by arylboronic acid chemosensors have mainly involved the elucidation of equilibrium constants and the role of boron-nitrogen interactions in signal transduction. However, several discreet sugarboronate complexes exist in solution. This is due to the complex equilibria between isomeric species of even the simplest monosaccharides. Relatively few reports have been devoted to a systematic study of the structures of each of the corresponding individual sugar-boronate complexes. We have investigated some of the precise regio- and stereochemical features of the various equilibrating sugar isomers that induce selective signal transduction. As a result of this …

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Paleoceanography Of The Gulf Of Papua Using Multiple Geophysical And Micropaleontological Proxies, Lawrence A. Febo Jan 2007

Paleoceanography Of The Gulf Of Papua Using Multiple Geophysical And Micropaleontological Proxies, Lawrence A. Febo

LSU Doctoral Dissertations

Recent marine and late Pleistocene sediments examined from the Gulf of Papua (GoP), Papua New Guinea investigate the flux and fate of detrital sediments and organic carbon over the last glacial-interglacial cycle. Based on surface sediment magnetic susceptibility (MS) and calcium carbonate concentrations, recent marine sediment is exported off the narrow shelf and into deeper regions via the Kerema Canyon of the northern Pandora Trough. Detrital clastic sediment is then dispersed deeper into the central and southern Pandora Trough. Except for pelagic deposition, very little detrital material reaches the Ashmore Trough and Eastern Plateau adjacent to the Great Barrier Reef. …

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Investigation Of Phospholipid Tubule Morphology For Use In Drug Delivery, Colleen Colson Garrett Jan 2007

Investigation Of Phospholipid Tubule Morphology For Use In Drug Delivery, Colleen Colson Garrett

LSU Doctoral Dissertations

Spherical vesicles consisting of phosphatidylcholines in which diacetylene groups have been inserted in the hydrocarbon tail centers give rise to hollow cylindrical tubes, known as “tubules”. The study of tubules has become an area of intense interest in recent years due to their unusual morphology, which raises several profound theoretical issues and suggests their use in a variety of applications. Tubule hollowness suggests medical and industrial encapsulations as well as filtration and purification applications. These potential uses, e.g., for drug and gene delivery, requires optimization of their morphology for the application. Tubules have many technologically desirable properties, such as a …

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Chemical Differences Of Atherosclerotic Plaques In Native And Bypass Human Coronary Arteries And Diseased And Non-Diseased Human Aortas, Samuel Jean Washington Jan 2007

Chemical Differences Of Atherosclerotic Plaques In Native And Bypass Human Coronary Arteries And Diseased And Non-Diseased Human Aortas, Samuel Jean Washington

LSU Doctoral Dissertations

ABSTRACT Cardiovascular disease, primarily atherosclerosis involves a number of distinct processes that are associated with plaque development. The use of differential gel electrophoresis to determine differences between proteins produced in native and bypass coronary arteries from the same heart has been studied. The analytical techniques presented in this study to characterize plaque samples include two dimensional gel electrophoresis, sodium dodecylsulfate polyacrylamide gel electrophoresis, mass spectrometry, differential gel electrophoresis, and high performance liquid chromatography. An overview of the stages involved in atherosclerosis and the theories implicated in the manifestation of atherosclerosis was presented. A design study using the Box Behnken method …

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Will Lowering Estuarine Salinity Increase Gulf Of Mexico Oyster Landings?, R. Eugene Turner Jun 2006

Will Lowering Estuarine Salinity Increase Gulf Of Mexico Oyster Landings?, R. Eugene Turner

Faculty Publications

Previous studies provide conflicting opinions on whether lower than average salinities in Gulf of Mexico (GOM) estuaries are likely to increase or decrease oyster harvests (Crassostrea virginica), which represented 69% and 54% of the United States oyster landings by weight, and dockside value, respectively, in 2003. The present study examined a 54-yr record (1950–2003) of oyster harvests and river discharge in five major estuaries in GOM states (Florida, Alabama, Mississippi, Louisiana, and Texas). Oyster landings were inversely related to freshwater inflow. Peaks in landings, 21 of 23 in West Florida, Alabama, Mississippi, and Texas combined, were coincidental with …

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Oxygen Depletion In The Gulf Of Mexico Adjacent To The Mississippi River, Nancy N. Rabalais, R. Eugene Turner Jan 2006

Oxygen Depletion In The Gulf Of Mexico Adjacent To The Mississippi River, Nancy N. Rabalais, R. Eugene Turner

Faculty Publications

The seasonal formation of a bottom water layer severely depleted in dissolved oxygen has become a perennial occurrence on the Louisiana continental shelf adjacent to the Mississippi River system. Dramatic changes have occurred in this coastal ecosystem in the last half of the 20th century as the loads of dissolved inorganic nitrogen tripled. There are increases in primary production, shifts in phytoplankton community composition, changes in trophic interactions, and worsening severity of hypoxia. The hypoxic conditions (dissolved oxygen less than 2 mg l-1) cover up to 22,000 km2 of the seabed in mid-summer. Dissolved oxygen concentrations seldom decrease to anoxia, …

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Integrating Micro-Scale Separations To Matrix Assisted Laser Desorption And Ioniation Time Of Flight Mass Spectrometry (Maldi-Tof-Ms) For Protein Analysis, Harrison K. Musyimi Jan 2006

Integrating Micro-Scale Separations To Matrix Assisted Laser Desorption And Ioniation Time Of Flight Mass Spectrometry (Maldi-Tof-Ms) For Protein Analysis, Harrison K. Musyimi

LSU Doctoral Dissertations

This dissertation describes the integration of micro-scale separations to matrix assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI TOF MS) for protein analysis. MALDI MS provides unsurpassed accurate mass measurements of intact bio-molecules, for example peptides and proteins, which in turn generate high molecular specificity enabling the identity, function and structure of these molecules to be characterized. However, in order to realize the full potential of MS in proteomic studies, integrated sample processing on automated and high throughput platforms is required to address the complexity, diversity and the dynamic range of proteomic analysis. The work described here contributes towards …

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Porous Inorganic-Organic Materials Based On Beta-Diketone Ligands, Yixun Zhang Jan 2006

Porous Inorganic-Organic Materials Based On Beta-Diketone Ligands, Yixun Zhang

LSU Doctoral Dissertations

Synthesis and characterization of porous inorganic-organic materials have been studied mainly on two linear β-diketone multifunctional ligands: pyridine based pyacH and isocyanide based HacphNC. As a known ligand, the preparation of pyacH has been improved with higher yield. When pyacH reacts with Fe and Al metal salts, trigonal metal β-diketonate building blocks M(pyac)3 are produced. When pyacH reacts with zinc acetate, both trans and cis Zn(pyac)2 are produced, both isomers were isolated and characterized by single-crystal X-ray crystallography. Solutions of the trigonal building block Fe(pyac)3 generate various crystal structures on reaction with AgNO3 in CH3CN. When the concentration of AgNO3 …

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Ontology-Based Methodology For Error Detection In Software Design, Allyson M. Hoss Jan 2006

Ontology-Based Methodology For Error Detection In Software Design, Allyson M. Hoss

LSU Doctoral Dissertations

Improving the quality of a software design with the goal of producing a high quality software product continues to grow in importance due to the costs that result from poorly designed software. It is commonly accepted that multiple design views are required in order to clearly specify the required functionality of software. There is universal agreement as to the importance of identifying inconsistencies early in the software design process, but the challenge is how to reconcile the representations of the diverse views to ensure consistency. To address the problem of inconsistencies that occur across multiple design views, this research introduces …

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Belowground Biomass Of Spartina Alterniflora: Seasonal Variability And Response To Nutrients, Faith Armand Darby Jan 2006

Belowground Biomass Of Spartina Alterniflora: Seasonal Variability And Response To Nutrients, Faith Armand Darby

LSU Doctoral Dissertations

Spartina alterniflora is a salt marsh macrophyte found from Canada to the Gulf of Mexico which often provides the dominant plant cover. Although S. alterniflora is well known for its high aboveground productivity, fifty to ninety percent of the total plant production occurs belowground. No previous studies address the seasonal variation of belowground biomass or the response of above-and belowground biomass to nutrients at the southern limits of its U. S. range. The objectives of this study were to: 1) document the seasonal variability of its above- and belowground biomass and test for responses to various combinations of N, P, …

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Development Of Analytical Techniques For The Analysis Of Submicron Particles And Protein Aggregates, Yohannes H. Rezenom Jan 2006

Development Of Analytical Techniques For The Analysis Of Submicron Particles And Protein Aggregates, Yohannes H. Rezenom

LSU Doctoral Dissertations

The goal of the research presented in this dissertation is to develop analytical techniques for the analysis of heterogeneous mixtures of submicron particles and protein aggregates. In Chapter 2, a simple and reproducible technique for constructing perfectly aligned gaps in fused-silica capillaries has been developed for postcolumn reagent addition with capillary electrophoresis (CE) to take advantage of laser-induced fluorescence (LIF) detection. This technique uses laser ablation with a Nd:YAG laser to create gaps of 14.0 ¡Ó 2.2 ƒÝm. These structures have been used for reagent addition for postcolumn derivatization with LIF detection and have been tested for the separation of …

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Influence Of Surface Chemistry On The Aggregation Of Beta Amyloid Peptide, Mariah Joan Wooldridge Mcmasters Jan 2006

Influence Of Surface Chemistry On The Aggregation Of Beta Amyloid Peptide, Mariah Joan Wooldridge Mcmasters

LSU Doctoral Dissertations

Alzheimer's disease is a progressive neurological ailment affecting 4.5 million aging Americans. The disease is characterized by the presence in the brain of self-assembled fibrils consisting of beta amyloid protein (Aβ). Soluble Aβ protein is present in normal human cerebrospinal fluid, but it is unclear what makes the protein aggregate into insoluble plaques. There is evidence that the Aβ fibril assembly is affected by interactions with biological surfaces, such as neuronal membranes. Here, surfaces consisting of self-assembled alkanethiol monolayers with different end groups were used to test the effect of surface chemistry on the structure and morphology of aggregates formed …

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Some Factors Affecting The Interfacial Interaction At Thermomechanical Pulp Fiber And Polypropylene Interphase, Sangyeob Lee Jan 2006

Some Factors Affecting The Interfacial Interaction At Thermomechanical Pulp Fiber And Polypropylene Interphase, Sangyeob Lee

LSU Doctoral Dissertations

This dissertation focused on some selected factors that influence the interfacial interactions at the interphase between wood based materials and thermoplastic surfaces. Several treatments were applied to enhance interfacial properties. In general, interfacial properties were altered by physical and chemical surface modification. Study of the interfacial interactions between wood fiber surfaces as a reinforced material and thermoplastics as a matrix material is important to understand fundamentals of wood fiber-plastic composites (WPC). This study represents fundamental research to define treatment effects on surfaces of wood pulp fibers and polypropylene (PP) film. Two thermosets, ion implantations, and maleic anhydride (MA) grafting were …

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Quantifying Changes In Fish Habitat Use In Coastal Waters Of Louisiana, Usa: A Hydroacoustic Approach, Kevin Mershon Boswell Jan 2006

Quantifying Changes In Fish Habitat Use In Coastal Waters Of Louisiana, Usa: A Hydroacoustic Approach, Kevin Mershon Boswell

LSU Doctoral Dissertations

The development of reliable tools for identifying essential fish habitat (EFH) has proven problematic. Knowledge of the distribution and biomass of fishes over discrete habitat types is a prerequisite for effective use of EFH in the management of important commercial and recreational fish species. Resolution of the influence of habitat type and environmental factors on the distribution of fishes is confounded by limitations of traditional sampling gears. To date, hydroacoustic technology has been widely accepted as a tool for surveying fishery resources; however few studies have implemented acoustics in ultra shallow (<2 m) coastal waters. Efforts should be made to utilize hydroacoustics for quantifying changes in fish distributions within estuarine environments given the benefits provided through acoustic technology (e.g. ease of deployment, reduced sampling effort, and non-invasive sampling attributes). A technique was developed for acoustically sensing fishes in the shallow, turbid waters of Barataria Bay, Louisiana. A robust and lightweight remotely-controlled transducer platform was designed for deploying acoustic gear. Sources of scattering within the bay were identified through a series of exclosure net experiments designed to quantify potential effects of plankton and suspended solids on acoustic scattering. Analysis filters were developed to reduce the effects of bubble-induced noise, often observed during periods when wind speeds were greater than 4.5 m s-1. Side-aspect acoustic target strength-length and target …

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Characterization Of Beta-Amyloid Peptide Aggregation And Acceleration With Non-Fibrillar Forming Peptide-Based Mediators, Nadia J. Edwin Jan 2006

Characterization Of Beta-Amyloid Peptide Aggregation And Acceleration With Non-Fibrillar Forming Peptide-Based Mediators, Nadia J. Edwin

LSU Doctoral Dissertations

Protein aggregation occurs under many circumstances, from the dynamic assembly of tubulin to form microtubules, the aggregation of actin into filaments, as well as plaque formation by amyloid precipitation. One important requirement in studying the mechanism of amyloid aggregation is the ability to monitor the growth kinetics over a wide range in size scales (10 nm to microns) with time that spans microseconds to seconds. Understanding the mechanisms of the aggregation may then lead to improved design of drugs to help control or suppress the aggregation process. In this dissertation, the physical characterization of the â-amyloid peptide and its interaction …

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