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Full-Text Articles in Physical Sciences and Mathematics

Quantitative Clay Mineralogy Of Several Louisiana Soils, Johan Forsman Jan 2005

Quantitative Clay Mineralogy Of Several Louisiana Soils, Johan Forsman

LSU Master's Theses

A method was developed to simplify the approach to obtaining a better quantitative representation (QR) of complex clay mineral assemblages by XRD analysis. The method has eight steps: 1) preparation of samples with preferred orientation; 2) qualitative identification of phases; 3) peak decomposition to obtain precise locations of individual peaks contained within broad diffraction bands; 4) creation of a library of theoretical XRD patterns by modeling of one-dimensional XRD patterns; 5) selection of experimental library patterns; 6) employing the LINEST function found in common spreadsheet software to fit library patterns to experimental patterns; 7) evaluation of results to determine needed …


Visualization Based On Interactive Clipping: Application To Confocal Data, Gaurav Khanduja Jan 2005

Visualization Based On Interactive Clipping: Application To Confocal Data, Gaurav Khanduja

LSU Master's Theses

We have explored how clipping can be exploited in an interactive manner to visualize massive three-dimensional datasets. In essence, the proposed interactive clipping approach involves the dynamic adjustment of the clipping plane to expose any cross-section of the volume data and subsequent adjustment of the clipped surface to the best view position using a combination of rotation and translation. The thesis describes the design, implementation and application of our interactive-clipping-based visualization system. The implementation is done with OpenGL and C++, thus resulting in a highly portable and flexible system. For illustration, two types of scientific datasets, confocal data of a …


Using Ground Penetrating Radar, Light Detection And Ranging, Geodetic Leveling, And Area Hydrogeology To Study The Baton Rouge And Scotlandville Faults, East Baton Rouge Parish, La, Angela Mooi Thomas Jan 2005

Using Ground Penetrating Radar, Light Detection And Ranging, Geodetic Leveling, And Area Hydrogeology To Study The Baton Rouge And Scotlandville Faults, East Baton Rouge Parish, La, Angela Mooi Thomas

LSU Master's Theses

East Baton Rouge Parish, Louisiana, is situated on at least two faults, the Baton Rouge Fault and the Denham Springs-Scotlandville Fault. These faults have surface expressions in the form of escarpments and damage to man-made structures. The purpose of this thesis is to study these faults in the shallow subsurface, in climate and soils found in Louisiana, and to study their ability to block fluid flow and whether groundwater withdrawal influences the amount and rate of subsidence along these faults. Techniques used to gather field data or to research and compile previously acquired data for this thesis includes: Ground Penetrating …


Do Predator Exclusion, Position, And Plant Architecture Influence Hydrilla-Dwelling Macroinvertebrate Communities?, Jonathan C. Fisher Jan 2005

Do Predator Exclusion, Position, And Plant Architecture Influence Hydrilla-Dwelling Macroinvertebrate Communities?, Jonathan C. Fisher

LSU Master's Theses

Hydrilla verticillata invaded south central Louisiana during the 1970s subsequently becoming the dominant submerged macrophyte in floodplain habitats of the Atchafalaya River Basin. The effects of hydrilla on littoral habitat structure, water quality, fish, and macroinvertebrates have been pervasive, and I hypothesized that dense hydrilla stands would also impact vertebrate predation on resident macroinvertebrates, although predation effects would likely be mediated by bed position. During 2003 and 2004, I conducted exclosure experiments in the Atchafalaya River Basin with artificial substrates to test for variations in hydrilla bed macroinvertebrate communities caused by predation, plant architecture, and bed position. To determine invertebrates …


Geologic Variability And Holocene Sedimentary Record On The Northern Gulf Of Mexico Inner To Mid-Continental Shelf, Triniti A. Dufrene Jan 2005

Geologic Variability And Holocene Sedimentary Record On The Northern Gulf Of Mexico Inner To Mid-Continental Shelf, Triniti A. Dufrene

LSU Master's Theses

Sidescan Sonar, chirp sonar sub-bottom profiles, and grab samples were collected on the north-central Gulf of Mexico continental shelf as part of an interdisciplinary study mapping juvenile red snapper habitat. Demarcation of essential fish habitat for juvenile red snapper (Lutjanus campechansis) in the Gulf of Mexico is considered critical for effective management of this valuable species. The first goal of this study was to map and describe the geology of this region. The second goal was to attempt to relate variations in geology to juvenile red snapper abundance and distribution. Sidescan mosaics were created for ten polygons, ranging in size …


The Asymptotic Z-Transform, Scott Jude Champagne Jan 2005

The Asymptotic Z-Transform, Scott Jude Champagne

LSU Master's Theses

Sequences of numbers and transformations from sequences to functions have been studied extensively, including the multiplication of two sequences through convolution and the equivalent multiplication of functions. The focal points of this thesis are the convolution field of causal sequences and their Z-transforms. Classically, the treatment of the Z-transform has been limited to those causal sequences for which the power series has a nontrivial radius of convergence. In this thesis it is shown that the Z-transform can be extended to all causal sequences without compromising any of the operational properties of the classical Z-transform.


Offshore Oil And Gas Platforms As Stepping Stones For Expansion Of Coral Communities: A Molecular Genetic Analysis, Amy D. Atchison Jan 2005

Offshore Oil And Gas Platforms As Stepping Stones For Expansion Of Coral Communities: A Molecular Genetic Analysis, Amy D. Atchison

LSU Master's Theses

The northern Gulf of Mexico (GOM) is one of the most productive oil and gas exploration areas in the world, currently containing approximately 3,800 offshore platforms. These platforms serve as artificial reefs in shallow water, which until their introduction was nearly devoid of shallow hard substrata. The question is raised whether this newly available substrate could help expand coral populations in the GOM. In this study, I examined adult scleractinian corals on oil and gas platforms in the northern GOM, in the vicinity of the Flower Garden Banks (FGB; approximately 180 km SE of Galveston, Texas) and attempted to determine …


Nekton Utilization Of Black Mangrove (Avicennia Germinans) And Smooth Cordgrass (Spartina Alterniflora) Sites In Southwestern Caminada Bay, Louisiana, Melanie Christine Caudill Jan 2005

Nekton Utilization Of Black Mangrove (Avicennia Germinans) And Smooth Cordgrass (Spartina Alterniflora) Sites In Southwestern Caminada Bay, Louisiana, Melanie Christine Caudill

LSU Master's Theses

This is the first study to compare nekton use and habitat value among Spartina alterniflora (Spartina), Avicennia germinans (black mangrove), and transition (S. alterniflora and A. germinans) sites within Louisiana's salt marsh-mangrove ecotone. Fishes and crustaceans were collected in Caminada Bay during fall 2003 and spring 2004 using 4 m2, bottomless lift nets. Although analyses were unable to demonstrate significant differences in fish (p=0.0753) and crustacean (p=0.1457) densities and species composition (p=0.8801) across sites, habitat-specific trends in nekton use were evident. Fishes, including gulf killifish and sheepshead minnows, showed affinities for the Spartina site, while crustaceans, especially white shrimp, were …


Restoration Success Of Backfilling Canals In Coastal Louisiana Marshes, Joseph Baustian Jan 2005

Restoration Success Of Backfilling Canals In Coastal Louisiana Marshes, Joseph Baustian

LSU Master's Theses

The need for effective marsh restoration techniques in Louisiana is a pressing issue as the state continues to lose coastal wetlands. Returning spoil banks to canals, known as "backfilling", is an attractive restoration option because it restores marsh, prevents future wetland loss, and is cost effective. The direct conversion of marsh to canals and spoil banks accounted for over 22% of Louisiana's wetland loss from 1930 to 1990, and the indirect losses associated with canal dredging are even larger. The restoration success of 30 canals, backfilled twenty years ago, was examined in this study and compared to restoration success shortly …


Identifying Asphalt Construction As A Point Source Emitter Of Volatile Organic Compounds Near The Louisiana State University Ozone Monitoring Station, Sean Jason Kice Jan 2005

Identifying Asphalt Construction As A Point Source Emitter Of Volatile Organic Compounds Near The Louisiana State University Ozone Monitoring Station, Sean Jason Kice

LSU Master's Theses

The EPA has classified Baton Rouge as a non-attainment area for ozone pollution for many years. Since then Photochemical Assessment Monitoring Stations (PAMS) and other ozone monitoring stations around the metropolitan area have monitored for ozone, NOx, and more than 50 volatile organic compounds (VOCs) which are considered precursors to ozone pollution. Traditionally, automobile engines and industrial plants and refineries have been blamed as major point sources for VOC emissions and the ozone pollution they cause. This research focuses on another possible point source for failing ozone levels at one of the ozone monitoring stations located on the campus of …


Influences On The Establishment Of County Wildfire Risk Mitigation: The Case Of California's Fire Safe Councils, Timothy Richard Soileau Jan 2005

Influences On The Establishment Of County Wildfire Risk Mitigation: The Case Of California's Fire Safe Councils, Timothy Richard Soileau

LSU Master's Theses

In response to increased annual wildfire destruction and insufficient wildfire mitigation approaches from the federal government, the state of California adopted Public Resources Code Sections 4290 and 4291 in the year 1991. These laws force the removal of fire-causing agents from public and private areas, and establish what is known as defensible space. Defensible space is defined in Section 4291 as the area within the perimeter of a parcel, development, neighborhood, or community where basic wildland fire protection practices and measures are implemented, providing the key point of defense from an approaching wildfire or escaping structure fire. One method to …


Environmental Benefits Realized From Eradication Of The Non-Indigenous Insect Anthonomus Grandis Boheman, The Cotton Boll Weevil, Marc Stephen Bordelon Jan 2005

Environmental Benefits Realized From Eradication Of The Non-Indigenous Insect Anthonomus Grandis Boheman, The Cotton Boll Weevil, Marc Stephen Bordelon

LSU Master's Theses

At least one third of the insecticide used in agriculture has been used to control the boll weevil in cotton. Historically, these insecticides have been toxic to humans and harsh on the environment. In addition, the intensive use of chemical insecticides to control the boll weevil results in the disruption of naturally occurring biological control factors that regulate other insect pest populations causing a chain reaction of secondary pest populations that require treatment followed by resurgence and repeat treatment. This situation has resulted in the development of resistance to insecticides, high control costs and unacceptable levels of chemical insecticide contamination …


Performance Evaluation Of Two Czt Gamma Ray Imaging Systems, Laurie Kelly Jan 2005

Performance Evaluation Of Two Czt Gamma Ray Imaging Systems, Laurie Kelly

LSU Master's Theses

The purpose of this research was to evaluate the performance of the imaging characteristics of two versions of a cadmium zinc telluride (CZT) gamma radiation detector system called the Laboratory Radioactive Assay Tracer (LabRAT). The performance evaluation follows the National Electrical Manufacturers Association standards for pixellated detector cameras. The LabRAT detector system hardware was developed by Mosaic Imaging Technology, Inc. LabRAT is a portable nuclear medicine imaging detector system intended for small field of view applications such as small animal imaging, portable radioisotope imaging in emergency room or intensive care units, and as an instruction tool for radiology residents and …


Identification Of 'Structural Alerts' And Associated Mechanisms Of Action Of Mammary Gland Carcinogens In Female Rodents, Shanna Tommika Moss Jan 2005

Identification Of 'Structural Alerts' And Associated Mechanisms Of Action Of Mammary Gland Carcinogens In Female Rodents, Shanna Tommika Moss

LSU Master's Theses

A new structure-activity relationship (SAR) approach to modeling was utilized to study mammary gland carcinogens. A set of chemicals tested for mammary tumorigenesis that have been analyzed in the Carcinogenic Potency Database (CPDB) were subjected to several computational analyses in an attempt to predict each chemical’s carcinogenic potential. A total of six learning sets (rat and mouse mammary gland carcinogen, CPDB rat and mouse, and female-specific rodent models) were developed and validated using a SAR modeling algorithm called categorical-SAR (cat-SAR). The predictive cat-SAR program evaluates active and inactive compounds of known biological activity and predicts their biological activity from this …


Sensorsimulator: Simulation Framework For Sensor Networks, Cariappa D. Mallanda Jan 2005

Sensorsimulator: Simulation Framework For Sensor Networks, Cariappa D. Mallanda

LSU Master's Theses

Wireless sensor networks have the potential to become significant subsystems of engineering applications. Before relegating important and safety-critical tasks to such subsystems, it is necessary to understand the dynamic behavior of these subsystems in simulation environments. There is an urgent need to develop a simulation platform that is useful to explore both the networking issues and the distributed computing aspects of wireless sensor networks. Current approaches to simulating wireless sensor networks largely focus on the networking issues. These approaches use well-known network simulation tools that are often difficult to extend to explore distributed computing issues. Discrete-event simulation is a trusted …


Naturally-Derived Porphyrin And Chlorin Photosensitizers For Photodynamic Therapy, Jodie Angela Hargus Jan 2005

Naturally-Derived Porphyrin And Chlorin Photosensitizers For Photodynamic Therapy, Jodie Angela Hargus

LSU Master's Theses

In oncologic applications of photodynamic therapy (PDT), the discriminating localization of porphyrin-type compounds in solid tumors is exploited for the selective ablation of neoplastic tissue with minimal destruction and irritation to normal tissue. PDT is a locoregional, binary cancer therapy in which a photosensitizer—light-activated drug—absorbs light of an appropriate wavelength and excites to the singlet state. This photosensitizer in the excited singlet state can undergo an internal transition to the excited triplet state, a relatively long-lived and high-energy species that transfers its excess energy to molecular oxygen. Molecular oxygen subsequently excites from the stable triplet state to the highly reactive …


A Parallel Computing-Visualization Framework For Polycrystalline Minerals, Venkatasrirama Pavankumar Yerraguntla Jan 2005

A Parallel Computing-Visualization Framework For Polycrystalline Minerals, Venkatasrirama Pavankumar Yerraguntla

LSU Master's Theses

In this report, we have reported some preliminary results in the development of a parallel computing-visualization framework for large-scale molecular dynamics simulations of polycrystals of minerals, which are geophysically relevant for Earth’s mantle. First, we have generated the input configurations of atoms belonging to various grains distributed in the space in a way, which resembles the polycrystalline structure of the minerals. The Input configuration is developed using Voronoi geometry. Thus generated polycrystalline system is simulated using the PolyCrystal Molecular Dynamics algorithm. Performance tests conducted using up to 256 processors and a couple of millions of atoms have shown that the …


Assessment Of Water Conservation Technique In Rice Culture To Develop Water Use Policies, Manoch Kongchum Jan 2005

Assessment Of Water Conservation Technique In Rice Culture To Develop Water Use Policies, Manoch Kongchum

LSU Master's Theses

The rapid growth of world population has resulted in significantly increased global water demand. According to a recent report on limited water supply, conservation techniques and water use policies are needed to preserve water resources. Worldwide agriculture is the largest consumer of water, particularly for growing rice. Water use for rice production was chosen because rice will continue to be a staple crop for the majority of the world’s population and because of its pervasive use of water. Hence, this thesis was designed to investigate water conservation possibilities for rice production in two water management regimes: alternate flooding and drying, …


Effects Of Adding Sediment To A Fresh Water Thin Mat Floating Marsh, Kate Carpenter Jan 2005

Effects Of Adding Sediment To A Fresh Water Thin Mat Floating Marsh, Kate Carpenter

LSU Master's Theses

Floating marshes are wetlands of emergent vascular vegetation which have a significant mat of live and dead roots, decomposing and dead organic material, and mineral sediments. This mat moves vertically as ambient water levels rise and fall. These marshes have unique hydrology in that overland sheet flow is reduced or eliminated leaving no inorganic sediment input, but there is extensive belowground water exchange. The effect of significant sediment introduction into wetlands with floating marshes is unknown. The purpose of this study was to observe the marsh mat response to Mississippi River sediment addition and measure species composition change and growth …


Platform Recruited Reef Fish, Phase I: Do Platforms Provide Habitat That Increase The Survival Of Juvenile Reef Fishes?, Lauren Kay Nowling Jan 2005

Platform Recruited Reef Fish, Phase I: Do Platforms Provide Habitat That Increase The Survival Of Juvenile Reef Fishes?, Lauren Kay Nowling

LSU Master's Theses

There are currently over 4000 functioning oil and gas platforms in the northern Gulf of Mexico (Gulf). Platform operations, and their prior drilling operations, produce trace amounts of lead, barium, vanadium, and lanthanum residues that are leached into the surrounding waters and are deposited on the sea floor. These residues have isotopic ratios different from those typical of the Gulf seafloor and can be used as harmless ‘fingerprints’ if they become incorporated into hard-parts or tissues in fishes associated with oil and gas platforms. From 2002 to 2004, 115 red snapper were collected from oil and gas platforms and artificial …


Effect Of Estradiol-17b On The Gonadal Developemnt Of Diploid And Triploid Female Eastern Oysters, Roberto Quintana Jan 2005

Effect Of Estradiol-17b On The Gonadal Developemnt Of Diploid And Triploid Female Eastern Oysters, Roberto Quintana

LSU Master's Theses

Declines in annual oyster landings and problems associated with seasonal reduction of oyster meat yields have increased interest for development of techniques to produce oysters with enhanced growth characteristics. Research interest has been focused on developing improved lines by induction of polyploidy. The goal of the present study was to evaluate the enhancement of gonadal development of triploid oysters, by the use of the hormone estradiol 17-â (E2) to produce viable eggs for the development of tetraploid broodstocks. Previous studies with the Pacific oyster, Crassostrea gigas, have shown: (1) the need to use the larger eggs of triploid females to …


Diagenesis Of Mudstones, Offshore Texas And Southwestern Louisiana, Maria Antonieta Pacheco Jan 2005

Diagenesis Of Mudstones, Offshore Texas And Southwestern Louisiana, Maria Antonieta Pacheco

LSU Master's Theses

Predicting the effects of mudstone diagenesis on reservoir quality is an important component of successful petroleum exploration and production programs. A regional study using chemical analyses from mudstone core cuttings and SP logs from 15 wells from the western Gulf of Mexico, including the Matagorda, Brazos, Mustang offshore areas, indicates that chemical changes with depth such as overall depletion of quartz and calcite; the illite-smectite conversion; and K2O enrichment occur in the mudstone Miocene interval of the study area. Mixing of depositional sources has been suggested to be the cause of similar chemical and mineralogical changes observed in Paleocene-Eocene and …


Riding Out The Risks: An Ethnographic Study Of Risk Perceptions In A South Louisiana Bayou Community, Susan Camille Manning Jan 2005

Riding Out The Risks: An Ethnographic Study Of Risk Perceptions In A South Louisiana Bayou Community, Susan Camille Manning

LSU Master's Theses

This ethnographic study explores the risk perceptions of a small unincorporated coastal community in southeastern Louisiana. This community has experienced social and environmental change due to events including tropical storms and hurricanes, erosion, subsidence, oil and gas activities, development, and the impact of global seafood markets. Many global risk perception studies have focused on the perception of risk to human health and property connected with natural and technological disasters, but few have explored the issue of minorities and small at-risk communities. To explore this theoretical and methodological gap, this study uses a variety of qualitative ethnographic methods to examine a …


Benthic Communities In The Northern Gulf Of Mexico Hypoxic Area: Potential Prey For Demersal Fish, Melissa Millman Baustian Jan 2005

Benthic Communities In The Northern Gulf Of Mexico Hypoxic Area: Potential Prey For Demersal Fish, Melissa Millman Baustian

LSU Master's Theses

Bottom-water hypoxia (≤2 mg O2 l-1) usually occurs on an annual basis on the Louisiana/Texas continental shelf from mid-May through mid-September over a large area (up to 20,000 km2 in mid-summer). The effects of hypoxia on the benthic infauna (potential prey) for demersal fish were examined, because changes in optimal diet can lead to negative impacts on growth and reproduction. Benthic samples were taken in three areas (inshore and offshore out of hypoxia and in the hypoxic area) during August 2003. Samples were also taken monthly from September 2003 to October 2004 at a fixed station …


Simulation Study Of Routing Protocols In Wireless Sensor Networks, Vatsalya Kunchakarra Jan 2005

Simulation Study Of Routing Protocols In Wireless Sensor Networks, Vatsalya Kunchakarra

LSU Master's Theses

Wireless sensor networks, a distributed network of sensor nodes perform critical tasks in many application areas such as target tracking in military applications, detection of catastrophic events, environment monitoring, health applications etc. The routing protocols developed for these distributed sensor networks need to be energy efficient and scalable. To create a better understanding of the performance of various routing protocols proposed it is very important to perform a detailed analysis of them. Network simulators enable us to study the performance and behavior of these protocols on various network topologies. Many Sensor Network frameworks were developed to explore both the networking …


Energy Aware Topology Control Protocols For Wireless Sensor Networks, Shilpa Dhar Jan 2005

Energy Aware Topology Control Protocols For Wireless Sensor Networks, Shilpa Dhar

LSU Master's Theses

Wireless Sensor Network has emerged as an important technology of the future due to its potential for application across a wide array of domains. The collaborative power of numerous autonomousremote sensing nodes self configured into a multi hop network permits in-depth accurate observation of any physical phenomenon. A stringent set of computational and resource constraints make the design and implementation of sensor networks an arduous task. The issue of optimizing the limited and often non-renewable energy of sensor nodes due to its direct impact on network lifetime dominates every aspect of wireless sensor networks. Existing techniques for optimizing energy consumption …


Detection And Evaluation Of Temperature Effects On Cell Proliferation In Somatic Tissues Of The Eastern Oyster, Crassostrea Virginica, By Flow Cytometry, Fernando Jimenez Jan 2005

Detection And Evaluation Of Temperature Effects On Cell Proliferation In Somatic Tissues Of The Eastern Oyster, Crassostrea Virginica, By Flow Cytometry, Fernando Jimenez

LSU Master's Theses

The goal of this thesis was to evaluate temperature effects on cell proliferation of eastern oyster somatic tissues for the development of an oyster cell line. Understanding the in vivo cell proliferation of an organism is essential for the development of cell culture. Cell proliferation can be measured by identifying nuclear cellular proteins involved in growth regulation and cellular transformation. The primary objectives of this study were to: 1) develop an assay to evaluate cell proliferation, 2) develop an assay to analyze nuclear RNA content, and 3) evaluate temperature effects on cell proliferation in somatic tissues. Proliferating cell nuclear antigen …


Modern Interpretation Of Euclid's Theory Of Ratio And Proportion, Mark Robert Stecher Jan 2005

Modern Interpretation Of Euclid's Theory Of Ratio And Proportion, Mark Robert Stecher

LSU Master's Theses

Euclid’s Elements is the foundation for geometry. Book V of Euclid’s Elements, which is independent from the earlier books, focuses on multiples, ratios, and proportions. This paper presents a model of the conceptual content of Book V, but using carefully selected modern notation to represent Euclid’s ideas without changing them drastically. All of the propositions and proofs from Euclid have been restated using just enough modern language to make clear for a modern reader. We also present a modern theory that bears analogy, proposition by proposition, to Euclid’s theory, but uses rigorous modern methods of proof.


Evaluation Of A Novel Method Of Predicting Estrogen Activity Of A Group Of Structurally Diverse Compounds, Daniel Consoer Jan 2005

Evaluation Of A Novel Method Of Predicting Estrogen Activity Of A Group Of Structurally Diverse Compounds, Daniel Consoer

LSU Master's Theses

The number of environmental chemicals found to have some level of endocrine activity has led to concern about the possible effects these compounds could have on human health and the health of other species, populations, and possibly whole ecosystems. The United States Environmental Protection Agency has been charged with testing a large number of these compounds, called endocrine-disrupting chemicals or hormonally active agents for hormonal activity. Limited testing resources have led to a call for alternate methods of screening, possibly for use in prioritizing this list to assist in efficient allocation of resources for further testing. This study describes a …


Use Of Terraced Marsh Habitats By Estuarine Nekton In Southwestern Louisiana, Bryan Paul Gossman Jan 2005

Use Of Terraced Marsh Habitats By Estuarine Nekton In Southwestern Louisiana, Bryan Paul Gossman

LSU Master's Theses

A variety of techniques have been employed in attempts to mitigate the extensive wetland loss occurring in coastal Louisiana. Marsh terracing is a wetland restoration technique that has rapidly gained in popularity in recent years. Terraces are assumed to benefit coastal restoration by providing areas for emergent plant growth, reducing wave energies, and increasing edge habitat to support nekton communities. The objectives of this study were to: 1) determine the effect of marsh terraces on adjacent water quality and sediment characteristics, 2) compare nekton abundance, species richness, and diversity in edge and open water habitats within terraced and unterraced ponds, …