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Articles 2011 - 2040 of 3417

Full-Text Articles in Physical Sciences and Mathematics

Quantitative Mapping Of Cyanobacterial Blooms Using Oceansat-1 Ocm Satellite Data, Padmanava Dash Jan 2011

Quantitative Mapping Of Cyanobacterial Blooms Using Oceansat-1 Ocm Satellite Data, Padmanava Dash

LSU Doctoral Dissertations

Cyanobacteria represent a major harmful algal group in fresh to brackish water environments. Lac des Allemands, a freshwater lake of 49 km2 southwest of New Orleans, Louisiana, provides a natural laboratory for remote characterization of cyanobacteria blooms because of their seasonal occurrence. This dissertation makes a contribution to research methodology pertaining to atmospheric correction of satellite data and development of remote sensing algorithms to quantify cyanobacterial pigments. The Ocean Color Monitor (OCM) sensor provides radiance measurements similar to Sea-viewing Wide Field-of-View Sensor (SeaWiFS) but with higher spatial resolution. However, OCM does not have a standard atmospheric correction procedure and …

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Synthesis, Biological And Photophysical Studies Of Novel Compounds For Cancer Therapy, Edith Khavwajira Amuhaya Jan 2011

Synthesis, Biological And Photophysical Studies Of Novel Compounds For Cancer Therapy, Edith Khavwajira Amuhaya

LSU Doctoral Dissertations

Cancer remains the second most common cause of death in the United States. It is therefore imperative that a lot of effort be put into finding a cure for this dreadful disease that shows no discrimination, and virtually anybody is at risk of developing the disease. Chapter 1 introduces basic facts about cancer and the available treatments, including PDT and BNCT. Our focus will be on these two bimodal therapies, which form the basis of my research work, which involves the synthesis of potential sensitizers to be used either in PDT or BNCT or both. In Chapter 2, I discuss …

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Advanced Semantics For Accelerated Graph Processing, Dylan Thomas Stark Jan 2011

Advanced Semantics For Accelerated Graph Processing, Dylan Thomas Stark

LSU Doctoral Dissertations

Large-scale graph applications are of great national, commercial, and societal importance, with direct use in fields such as counter-intelligence, proteomics, and data mining. Unfortunately, graph-based problems exhibit certain basic characteristics that make them a poor match for conventional computing systems in terms of structure, scale, and semantics. Graph processing kernels emphasize sparse data structures and computations with irregular memory access patterns that destroy the temporal and spatial locality upon which modern processors rely for performance. Furthermore, applications in this area utilize large data sets, and have been shown to be more data intensive than typical floating-point applications, two properties that …

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On Greenberg's Question: An Algebraic And Computational Approach, David H. Chapman Jan 2011

On Greenberg's Question: An Algebraic And Computational Approach, David H. Chapman

LSU Doctoral Dissertations

Greenberg asked whether arithmetically equivalent number fields share the same Iwasawa invariants. In this dissertation it is shown that the problem naturally breaks up into four cases, depending on properties of Galois groups. This analysis is then used to give a positive answer to Greenberg’s question in some nontrivial examples.

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A C0 Interior Penalty Method For The Von Kármán Equations, Armin Karl Reiser Jan 2011

A C0 Interior Penalty Method For The Von Kármán Equations, Armin Karl Reiser

LSU Doctoral Dissertations

In this dissertation we develop a C0 interior penalty method for the von Kármán equations for nonlinear elastic plates. We begin with a brief survey on frequently used finite element methods for the von Kármán equations. After addressing some topics from functional analysis in the preliminaries, we present existence, uniqueness and regularity results for the solutions of the von Kármán equations in Chapter 3. In the next chapter we review the C0 interior penalty method for the biharmonic problem. Motivated by these results, we propose a C0 interior penalty method for the linearized von Kármán equations in …

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Structural And Electronic Properties Of Noble Metals On Metal Oxide Surfaces, Fei Wang Jan 2011

Structural And Electronic Properties Of Noble Metals On Metal Oxide Surfaces, Fei Wang

LSU Doctoral Dissertations

Noble metals on metal oxide surfaces play crucial roles in many catalysis applications. Due to extreme complexity of the interfaces and catalytic reaction processes, basic science studies of model systems are needed to guide the construction and optimization of new industrial catalysts. We have employed ultra-high vacuum techniques to investigate the morphology, electronic structure, and surface reactivations of clean metal-oxide/metal nanocluster interfaces in ideal conditions. The systems we chose are Ag/TiO2, a popular photocatalyst, and Cu/ZnO, recently a hot candidate for liquid fuel production. The main characterization techniques that we have employed include Scanning Tunneling Microscopy (STM), Photoemission Spectroscopy (PES), …

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Spatial Ecology Of Adult Spotted Seatrout, Cynoscion Nebulosus, In Louisiana Coastal Waters, Jody Lynn Callihan Jan 2011

Spatial Ecology Of Adult Spotted Seatrout, Cynoscion Nebulosus, In Louisiana Coastal Waters, Jody Lynn Callihan

LSU Doctoral Dissertations

Spotted seatrout, Cynoscion nebulosus, are common in estuaries and coastal waters of the south Atlantic and Gulf of Mexico and are of considerable recreational and economic importance. Still, the spatial ecology of this species is under-studied and poorly resolved, especially in Louisiana waters. To address this important knowledge gap, I examined the movements, distribution, and habitat use of adult spotted seatrout in coastal Louisiana primarily using high-resolution acoustic telemetry and secondarily, conventional tagging (mark-recapture) data. At the largest spatial scale investigated, I found that adults exhibited a high degree of estuarine fidelity and rarely undertook large-scale movements in excess of …

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Capturing Elements In Matroid Minors, Deborah Chun Jan 2011

Capturing Elements In Matroid Minors, Deborah Chun

LSU Doctoral Dissertations

In this dissertation, we begin with an introduction to a matroid as the natural generalization of independence arising in three different fields of mathematics. In the first chapter, we develop graph theory and matroid theory terminology necessary to the topic of this dissertation. In Chapter 2 and Chapter 3, we prove two main results. A result of Ding, Oporowski, Oxley, and Vertigan reveals that a large 3-connected matroid M has unavoidable structure. For every n exceeding two, there is an integer f(n) so that if |E(M)| exceeds f(n), then M has a minor isomorphic to the rank-n wheel or whirl, …

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Extreme Scale Parallel Nbody Algorithm With Event Driven Constraint Based Execution Model, Chirag Dekate Jan 2011

Extreme Scale Parallel Nbody Algorithm With Event Driven Constraint Based Execution Model, Chirag Dekate

LSU Doctoral Dissertations

Traditional scientific applications such as Computational Fluid Dynamics, Partial Differential Equations based numerical methods (like Finite Difference Methods, Finite Element Methods) achieve sufficient efficiency on state of the art high performance computing systems and have been widely studied / implemented using conventional programming models. For emerging application domains such as Graph applications scalability and efficiency is significantly constrained by the conventional systems and their supporting programming models. Furthermore technology trends like multicore, manycore, heterogeneous system architectures are introducing new challenges and possibilities. Emerging technologies are requiring a rethinking of approaches to more effectively expose the underlying parallelism to the applications …

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Stories Of The Proterozoic Earth: Paleoproterozoic Chuanlinggou Arcitarchs And Neoproterozoic ¹⁷O-Depleted Barite, Yongbo Peng Jan 2011

Stories Of The Proterozoic Earth: Paleoproterozoic Chuanlinggou Arcitarchs And Neoproterozoic ¹⁷O-Depleted Barite, Yongbo Peng

LSU Doctoral Dissertations

This dissertation consists of two independent topics, both critical to understanding Earth history during the Proterozoic Eon. (1) Paleoproterozoic Chuanlinggou Acritarchs: The eukaryotic affinity of acritarchs from the Chuanlinggou Formation has been questioned because of lack of indisputable morphological evidence. In this study, Chuanlinggou acritarchs were examined by jointly using optical microscopy, scanning electron microscopy, and transmission electron microscopy. In most cases, an ovoidal group of acritarchs represents a half-vesicle following a complete longitudinal rupture, which is a morphological model different from a whole envelope with medial splits, as proposed by earlier studies. This ovoidal group displays a bipolar morphology, …

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Evaluation Of Methods To Predict Weibull Parameters For Characterizing Diameter Distributions, Krishna Prasad Poudel Jan 2011

Evaluation Of Methods To Predict Weibull Parameters For Characterizing Diameter Distributions, Krishna Prasad Poudel

LSU Master's Theses

Compared to other distribution functions, the Weibull distribution has been more widely used in describing diameter distributions because of its flexibility and relative simplicity. Parameters of the Weibull distribution are generally predicted either by the parameter prediction method or by the parameter recovery method. The coefficients of the regression equations for predicting Weibull parameters, moments, or percentiles are often estimated by use of different approaches such as ordinary least squares (OLS), seemingly unrelated regression (SUR) or cumulative distribution function regression (CDFR). However, there is no strong rationale for preferring one method over the other. We developed and evaluated different methods …

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Two-Particle Level Diagrammatic Approaches For Strongly Correlated Systems, Herbert Fotso Jan 2011

Two-Particle Level Diagrammatic Approaches For Strongly Correlated Systems, Herbert Fotso

LSU Doctoral Dissertations

This thesis presents the development of new numerical methods for the treatment of strongly correlated electron systems based on self-consistent approaches at both the one and the two-particle level such as the parquet formalism. The parquet formalism was solved for the first time on a two-dimensional cluster. When the fully irreducible vertex is approximated by the bare vertex, we obtain the parquet approximation. Its validity was investigated by comparing results that it produces to those of other conserving approximations such as the FLuctuation EXchange (FLEX) approximation or the Second Order Perturbation Theory (SOPT). We found that it provides a significant …

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Characterization And Prototyping Of The Rotating Modulator Hard X-Ray/Gamma-Ray Telescope, Brent Budden Jan 2011

Characterization And Prototyping Of The Rotating Modulator Hard X-Ray/Gamma-Ray Telescope, Brent Budden

LSU Doctoral Dissertations

A hard x-ray/gamma-ray telescope with high sensitivity and wide field of view would be capable of performing an all-sky census of black holes over a wide range of obscuration and accretion rates. As an example, NASA's Black Hole Finder Probe mission was designed to provide a 5-sigma flux sensitivity in a 1-year observation of ~0.02 mCrab in the 10 - 150 keV energy range and 0.5 mCrab in the 150 - 600 keV energy range with 3 - 5 minutes of arc angular resolution. These are significantly higher sensitivity and resolution goals than those of current instruments. The design focus …

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Proteomic Analysis Of The Blood Of Alligator Mississippiensis, Lancia Nadinia Fallen Darville-Bowleg Jan 2011

Proteomic Analysis Of The Blood Of Alligator Mississippiensis, Lancia Nadinia Fallen Darville-Bowleg

LSU Doctoral Dissertations

My research focus was to investigate alligator blood using mass spectrometry-based proteomics methods to understand their innate immune systems. The first goal was to sequence peptides and proteins from the blood serum and leukocytes using tandem mass spectrometry and de novo sequencing. The second goal was to determine the function of these biological molecules and their relationship to the immune system. One- and two-dimensional gel electrophoresis was used to separate proteins from alligator leukocytes, which were enzymatically digested. The peptides were measured using reversed phase nano-high performance liquid chromatography coupled with tandem mass spectrometry (nano-HPLC-MS/MS) followed with de novo sequencing. …

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Effects Of Ecotourist Pre-Purchase And External Information Search Behaviors And Strategies On Forest-Based Ecotourism Travel Decisions In Sri Lanka, Rangika T. Perera Jan 2011

Effects Of Ecotourist Pre-Purchase And External Information Search Behaviors And Strategies On Forest-Based Ecotourism Travel Decisions In Sri Lanka, Rangika T. Perera

LSU Doctoral Dissertations

In the 1980s, the term ecotourism emerged as a direct result of acknowledgment and reaction by travelers to global ecological practices. In reality, the concept of ecotourism carries wide applications, particularly for bio-diverse countries with unique natural attractions. Sri Lanka qualified as such a country, presenting a significant tourism resource base, that display natural and cultural phenomena, including forests, waterfalls, mountains, exotic flora and fauna, and a heritage equally as ancient and as rich as the Greeks and Romans. Ecotourism in today’s dynamic global environment demands that ecotourism operators face a keenly competitive market in order to present an appealing …

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Surface-Initiated Polymerization As A Novel Strategy Towards Preparation Of Organic Semiconducting Polymer Thin Films, Euiyong Hwang Jan 2011

Surface-Initiated Polymerization As A Novel Strategy Towards Preparation Of Organic Semiconducting Polymer Thin Films, Euiyong Hwang

LSU Doctoral Dissertations

Organic semiconducting polymer thin films are core materials for organic electronics that are conventionally prepared by solution processing techniques. Despite having the advantage of easy and fast thin film manufacturing, solution techniques have intrinsic drawbacks, such as disordered and poor molecular organization in the film (often resulting in poor device performance), as well as insufficient stabilities of the films and resulting devices. To improve this situation, we designed a novel “bottom-up” fabrication of surface-immobilized organic semiconducting thin films through in situ polymerization. This new strategy will allow high degree of control over molecular organization which therefore results in improved free …

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Application Of Scanning Probe Microscopy For New Physical Measurements And Studies Of Surface Chemical Reactions Of Materials At The Molecular Level, Stephanie Loletha Daniels Jan 2011

Application Of Scanning Probe Microscopy For New Physical Measurements And Studies Of Surface Chemical Reactions Of Materials At The Molecular Level, Stephanie Loletha Daniels

LSU Doctoral Dissertations

Scanning probe microscopy (SPM) provides unique capabilities for surface visualization and measurements that reach atomic and molecular dimensions. My research focus is directed toward applying and developing new measurements for analytical and surface chemistry with SPM. Two distinct goals based on studies with atomic force microscopy (AFM) will be described within this dissertation. The primary goal was to develop and apply a new AFM imaging mode for ultrasensitive measurements of the superparamagnetic properties of proteins. Magnetic sample modulation (MSM)-AFM, has capabilities to investigate and map the magnetic response of nanomaterials with unprecedented spatial resolution. The second goal was to apply …

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Kinetics And Mechanisms Of Release By Redox-Active Liposomes In Drug Delivery, Jerimiah Forsythe Jan 2011

Kinetics And Mechanisms Of Release By Redox-Active Liposomes In Drug Delivery, Jerimiah Forsythe

LSU Doctoral Dissertations

Liposomes have had a long and fruitful application of drug delivery devices in the treatment of select tumors and cancer types. Third-generation liposomes possess endogenous triggering methods that hold the ability for site-specific unloading of liposomal contents, thus providing necessary temporal and spatial control over contents release that can be tuned to match the drug efficacy for decreased side effects during treatment. Of these new endogenous triggers, redox-active liposomes that can be triggered to unload contents via two-electron reduction by enzymes or chemical means have demonstrated promise for the encapsulation and delivery of cargo. The research project undertaken involved the …

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Understanding The Selective Detection Of Homocysteine And Studies Toward The Synthesis Of Vinigrol, Dong Wang Jan 2011

Understanding The Selective Detection Of Homocysteine And Studies Toward The Synthesis Of Vinigrol, Dong Wang

LSU Doctoral Dissertations

The first part of the work is dedicated to the selective detection of Homocysteine (Hcy). In order to better understand this colorimetric detection method, a thermodynamic model for the pH dependence of the effective reduction potential of Hcy derived á-carbon radicals has been proposed. And using viologen indicators of varying reduction potentials, we demonstrate that colorimetric changes occur at experimental pH values consistent with the model. The one-carbon bridge stereochemistry of bicyclo[3.3.1]nonane framework is critical to make the third ring of the tricyclic precursor of vinigrol. We studied this stereochemistry carefully and found that the major diastereomer formed from Robinson …

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Microphytobenthos Of The Northern Gulf Of Mexico Hypoxic Area And Their Role In Oxygen Dynamics, Melissa Millman Baustian Jan 2011

Microphytobenthos Of The Northern Gulf Of Mexico Hypoxic Area And Their Role In Oxygen Dynamics, Melissa Millman Baustian

LSU Doctoral Dissertations

The presence or absence of microphytobenthos on the seafloor provides clues about whether benthic oxygen evolution contributes significantly to the oxygen budget of the hypoxic area in the northern Gulf of Mexico. Hypoxia (oxygen < 2 mg l-1) creates inadequate concentrations of dissolved oxygen to support most organisms, such as fish, shrimp and crabs, and occurs over large areas of the Louisiana continental shelf from spring through summer in most years. Oxygen production by benthic autotrophs may offset a decline in oxygen concentrations if there is a functioning community and sufficient light. I sampled three stations (14, 20 and 23 m depths) ~ 100 km west of the Mississippi River over three hypoxic annual cycles (2006 – 2008), and 11 stations along a 14 - 20 m contour on the shelf in late-July in 2006, 2007 and 2008. I used microscopy and high-performance liquid chromatography to estimate the biomass and composition of phytoplankton and microphytobenthos. The potential seasonal oxygen production was estimated in 2007 and 2008 by incubating coupled light/dark sediment cores and bottom water from two stations. The sediment community (cells > 3 um) differed from those in the water column and were frequently benthic pennate diatoms and filamentous cyanobacteria (58-88% seasonally and 1-99% in mid-summer). The concentration of microphytobenthic biomass was usually < 2.0 ug g dry sed-1, and various biotic parameters were influenced by light at the seafloor. Declines in dissolved oxygen over a seasonal cycle in 2007 and 2008 were affected more by the initial dissolved oxygen concentration than by the presence of microphytobenthos that could generate oxygen. The sediment (1.2 - 27.3 mmol O2 m-2 d-1, n = 97) and bottom-water (1.1 - 17.5 mmol m-2 d-1, n = 23) oxygen consumption rates were within the range of the few previously-reported data. This work adds to these data and also provides the only sediment oxygen consumption rates at fixed sites over seasonal time scales. These results provide critical input to three-dimensional, physical-biological models of oxygen dynamics for this hypoxic area.

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An Overview Of Green Jobs In The Louisiana Forest Sector, Ryan D. Olson Jan 2011

An Overview Of Green Jobs In The Louisiana Forest Sector, Ryan D. Olson

LSU Master's Theses

The term “green job” is a relatively new definition that defines employment activities that are likely to have occurred since the beginning of human existence. The push to identify, to quantify and to drive the growth of these jobs has recently been brought on by climate change and the depletion of Earth’s natural resources. According to the United States Department of Labor Bureau of Labor Statistics, green jobs are either (a) Jobs in businesses that produce goods or provide services that benefit the environment or conserve natural resources or (b) Jobs in which workers’ duties involve making their establishment’s production …

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Comparison Of The Age And Growth Of Red Snapper (Lutjanus Campechanus) Amongst Habitats And Regions In The Gulf Of Mexico, Courtney Rose Saari Jan 2011

Comparison Of The Age And Growth Of Red Snapper (Lutjanus Campechanus) Amongst Habitats And Regions In The Gulf Of Mexico, Courtney Rose Saari

LSU Master's Theses

The Gulf of Mexico (GOM) red snapper stock has been exploited since the mid 1800s; yet it is still one of the most economically important fisheries in the GOM. Red snapper have been managed as a unit stock and are currently overfished, but perhaps no longer undergoing overfishing. Habitat varies greatly throughout the GOM and while numerous studies have aged red snapper, none have simultaneously compared the age and size structure and growth rates among standing and toppled oil and gas platforms with natural habitats. The objectives of this study were to examine the size and age structure and growth …

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Cure-On Demand Wood Adhesives Using Frontal Polymerization Of Acrylates, Treyvon Holt Jan 2011

Cure-On Demand Wood Adhesives Using Frontal Polymerization Of Acrylates, Treyvon Holt

LSU Master's Theses

Frontal polymerization (FP) is when the monomer is polymerized by a zone of reaction propagating through the monomer. The reaction zone is fueled by the heat given off by the polymerization of the monomer. FP is a promisig method for curing adhesives because it allows for cure-on-demand and fast cure times. The monomers selected for the adhesive is the main factor in determining the adhesive’s properties. Trimethylolpropane triacrylate (TMPTA), pentaerythritol tetraacrylate (PETA), and other multifunctional monomers make the polymer formed more brittle. The brittleness can be reduced by using trimethylolpropane ethoxylate triacrylates (TMPEOTA) in the place of the other multifunctional …

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Aquatic Macroinvertebrate And Nekton Community Structure In A Chenier Marsh Ecosystem: Implications For Whooping Crane Prey Availability, Sung-Ryong Kang Jan 2011

Aquatic Macroinvertebrate And Nekton Community Structure In A Chenier Marsh Ecosystem: Implications For Whooping Crane Prey Availability, Sung-Ryong Kang

LSU Doctoral Dissertations

A suitable foraging habitat model based on prey density, biomass, and energy values in varying hydrologic conditions can provide an objective quantifiable method to assess habitat conditions for the Whooping Crane (Grus americana). Nekton and macroinvertebrates are considered the important prey sources in Whooping Crane's diet at different times. This study focuses on the understanding of habitat relationships of nekton and macroinvertebrate assemblage in the Chenier Plain to provide a foundation for the development for foraging suitability models for the reintroduced Whooping Crane. In this dissertation, in a laboratory study I experimentally examined the effect of salinity on …

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Development Of A Monte Carlo Based Correction Strategy For A Tg-43 Based Brachytherapy Treatment Planning System To Account For Applicator Inhomogeneities, Bobby Chon Mathews Jan 2011

Development Of A Monte Carlo Based Correction Strategy For A Tg-43 Based Brachytherapy Treatment Planning System To Account For Applicator Inhomogeneities, Bobby Chon Mathews

LSU Master's Theses

Purpose: The purpose of this work was to investigate the use of pre-calculated Monte Carlo (MC) ovoid and source-based attenuation-correction factors that would correct a commercially-available brachytherapy treatment planning system (TPS) generated plan in order to account for any dosimetric effects due to the presence of intracavitary brachytherapy (ICBT) applicators during treatment delivery. Methods: A MC model of an ICBT CT-MR compatible ovoid applicator set was confirmed utilizing radiochromic film (RCF). MC was used to simulate dose distributions resulting from eight source-dwell-positions within the ICBT applicator. Also, the American Association of Physicist in Medicine Task Group 43 Report (AAPM TG-43) …

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Single-Molecule Detection And Microfluidics: Generating Systems For The In Vitro Diagnostics Of Stroke, Brandon M. Young Jan 2011

Single-Molecule Detection And Microfluidics: Generating Systems For The In Vitro Diagnostics Of Stroke, Brandon M. Young

LSU Master's Theses

There is currently no available molecular diagnostic test for stroke; the common modality for diagnosis consists of computed tomography or magnetic resonance imaging. Unfortunately, the use of these diagnostic regimens can delay proper therapeutic treatment, which requires administration within the first 3 h of a stroke event. We are developing a molecular assay that can report, in near real time and at the point-of-care, the presence or absence of biomarkers specifically targeted for the diagnosis of ischemic or hemorrhagic stroke. The proposed strategy uses blood-borne mRNAs that are either under-expressed or over-expressed as a result of tissue damage within the …

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Comparison Of Tld Dose And Reconstructed Dose For Post-Mastectomy Radiation Therapy With Tomotherapy, Matthew Roberts Jan 2011

Comparison Of Tld Dose And Reconstructed Dose For Post-Mastectomy Radiation Therapy With Tomotherapy, Matthew Roberts

LSU Master's Theses

Purpose: To determine the dosimetric accuracy of TomoTherapy’s database technique for delivery verification and dose reconstruction in post-mastectomy radiation therapy (PMRT) treatments. Methods and Materials: Archived treatment data for 5 patients treated at MBPCC were restored to the TomoTherapy research computer system. Pretreatment MVCT images and exit detector dosimetry data collected during treatment of these patients were used to calculate the DV sinogram for each treatment fraction. The DV sinogram and MVCT image for each fraction were used to reconstruct the delivered dose for that fraction using a convolution/superposition algorithm. The reconstructed doses were compared to previously acquired TLD doses …

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Delivery Accuracy Of Image Guided Radiation Therapy Using Elekta Infinity's On-Board Imaging, Matthew William Sutton Jan 2011

Delivery Accuracy Of Image Guided Radiation Therapy Using Elekta Infinity's On-Board Imaging, Matthew William Sutton

LSU Master's Theses

Using the technique developed by Vinci et al. (2007), this project quantified the accuracy and precision of the Elekta Infinity using an end-to-end test for the entire image guided radiation therapy (IGRT) treatment process. The IGRT capabilities of the on-board imaging systems for megavoltage (MV) planar imaging and kilovoltage cone beam computed tomography (kVCBCT) were both evaluated. The accuracy of the on-board imaging systems will impact the size of planning treatment margins. A CIRS Radiosurgery head phantom with a Gafchromic EBT2 film dosimetry block insert was used to measure the dose distributions in the three orthogonal planes. A coplanar, isocentric, …

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The Design Of A Computer System To Determine The Causes Of Edema Using Magnetic Resonance Spectroscopy, Carl Allen Fink Jan 2011

The Design Of A Computer System To Determine The Causes Of Edema Using Magnetic Resonance Spectroscopy, Carl Allen Fink

LSU Master's Theses

Diabetes is a growing problem in the U.S.A., closely linked to the current obesity epidemic. Two common complications of diabetes, osteomyelitis of the foot, and Charcot's joint, are impossible to differentiate via traditional Magnetic Resonance Imaging. The background of Magnetic Resonance Spectroscopy, which transforms the time-domain MRI signal into the frequency domain spectrum, is explored, and its use to aid in this differentiation is proposed. Artificial Neural Networks can be employed to evaluate the MRS data and to automate the process.

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Laboratory Scale Seismic Analysis Of A Spatially Variable Hydrological Surface In Unconfined, Unconsolidated Sand, David E. Smolkin Jan 2011

Laboratory Scale Seismic Analysis Of A Spatially Variable Hydrological Surface In Unconfined, Unconsolidated Sand, David E. Smolkin

LSU Master's Theses

The ability to measure the depth to the water table can provide information such as reservoir characteristics, soil conditions for agriculture, and actions to be taken with contaminant flow and removal. We attempt to detect this boundary in a larger-than-lab scale experiment. We attempt to simulate a spatially variable water level and attempt to image changes in the depth of this water level. We try to reduce the normally complex natural conditions to those of a nominally homogeneous and isotropic, unconfined sand volume for modeling. These simplified conditions help isolate the effects of remaining complexities such as the variable saturation …

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