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Characterization Of The Lucinid Bivalve-Bacteria Symbiotic System: The Significance Of The Geochemical Habitat On Bacterial Symbiont Diversity And Phylogeny, Angela Marissa Green-Garcia Jan 2008

Characterization Of The Lucinid Bivalve-Bacteria Symbiotic System: The Significance Of The Geochemical Habitat On Bacterial Symbiont Diversity And Phylogeny, Angela Marissa Green-Garcia

LSU Master's Theses

Extensive characterization of a single lucinid bivalve habitat was conducted to characterize the relationship between host bivalve and thiotrophic bacterial endosymbionts. For lucinids, the ecological and evolutionary relationships between hosts and endosymbionts are poorly understood. Reconstructing the evolutionary history of lucinid endosymbiosis, and the geologic significance of the association, has been hampered by insufficient knowledge of endosymbiont ecology and taxonomic diversity. Host organisms (Lucinisca nassula and Phacoides pectinatus) were collected from Cedar Keys, Florida, within the top 15-20 cm of the sediment in sea grass beds. PCR amplification and sequencing of bacterial 16S rRNA genes from lucinid gills and sediment …


Dosimetry Intercomparison Using A 35-Kev X-Ray Synchrotron Beam, Scott Oves Jan 2008

Dosimetry Intercomparison Using A 35-Kev X-Ray Synchrotron Beam, Scott Oves

LSU Master's Theses

Significance: Photon activated Auger electron therapy utilizes a keV-ranged, monoenergetic x-ray beam, and radiobiological and animal experiments studying this therapy require accurate dosimetry techniques. However, there exist few dosimetry protocols for low-energy x-ray beams. This research intended to use the CAMD synchrotron as a source of monochromatic, 35-keV x-rays and test dosimetry techniques of film and ion chamber. The hypothesis of my research was that depth-dose measured in a PMMA phantom using an air-equivalent ionization chamber and radiochromic film dosimeters in a PMMA phantom irradiated by a 35-keV, monochromatic x-ray beam will agree to within 5% of each other and …


Segmented Field Electron Conformal Therapy Planning Algorithm, David Jaquet Perrin Jan 2008

Segmented Field Electron Conformal Therapy Planning Algorithm, David Jaquet Perrin

LSU Master's Theses

Purpose: Segmented-field electron conformal therapy (SFECT) is rarely used, or if used, used sub optimally, primarily due to inadequate tools for its planning. The development of SFECT planning tools could help begin to bring electron therapy to the same level of sophistication as x-ray and proton therapy, resulting in greater consideration by radiation oncologists. The purpose of this work was to develop a forward planning algorithm that will improve segmentation of the SFECT treatment field. It was hypothesized that a forward planning algorithm can produce segmented-field ECT fields that improve dose conformity as the number of beam energies is increased …


Computed Tomography Imaging To Quantify Iodine Distribution In Iododeoxyuridine-Labeled Dna, Christopher Erik Welch Jan 2008

Computed Tomography Imaging To Quantify Iodine Distribution In Iododeoxyuridine-Labeled Dna, Christopher Erik Welch

LSU Master's Theses

Purpose: Treatment planning for x-ray activated Auger electron radiotherapy requires knowledge of the spatial distribution of Auger electron-producing target atoms in DNA; iodine is a candidate atom. Because planning uses computed tomography (CT) data to show anatomy, obtaining the target atoms' distribution with CT methods is an attractive goal. This study evaluates the ability of two available CT systems to measure the target atoms' spatial distribution. Method and Materials: A polychromatic desktop CT scanner and a synchrotron monochromatic CT system acquired images of iodine concentrations in water, ranging from 0.03-10 mg/ml. The polychromatic scanner was operated at 40 kVp while …


Denitrification Enzyme Activity As An Indicator Of Nitrate Loading In A Wetland Receiving Diverted Mississippi River Water, Lisa Michelle Gardner Jan 2008

Denitrification Enzyme Activity As An Indicator Of Nitrate Loading In A Wetland Receiving Diverted Mississippi River Water, Lisa Michelle Gardner

LSU Master's Theses

The Davis Pond freshwater diversion discharges nutrient-rich Mississippi River water to a 3,760 ha receiving marsh in upper Barataria Basin, LA. Excess nitrate in the Mississippi River has been linked to algal blooms and hypoxia in the Gulf of Mexico with potential to negatively impact Barataria Basin. We hypothesized that 1) soil denitrification enzyme activity (DEA) will increase with higher surface water nitrate concentrations, and 2) the spatial distribution of DEA in Davis Pond marsh will provide information about the extent nitrate loading at a specific discharge rate. Intact soil cores collected from the marsh received a continuous flow of …


Spatial And Temporal Dynamics Of Stream Water Chemistry In A Headwater Catchment Of Central Louisiana, April Bryantmason Jan 2008

Spatial And Temporal Dynamics Of Stream Water Chemistry In A Headwater Catchment Of Central Louisiana, April Bryantmason

LSU Master's Theses

One of the dominant themes of stream water quality research has been the effect of nutrients and organic materials on eutrophication of coastal waters. Despite this prevalence in water quality research, few studies have been conducted on water quality changes in low-gradient watersheds under a humid, warm subtropical climate, such as those in the coastal plains of the Northern Gulf of Mexico. This study addresses: (1) the nutrient conditions in headwater streams of a low-gradient, subtropical watershed, especially as it relates to the suggested criteria by the Environtmental Protection Agency (EPA), (2) organic and inorganic carbon dynamics in the headwaters …


Comprehensive Planning In Louisiana, Lynn A. Maloney-Mújica Jan 2008

Comprehensive Planning In Louisiana, Lynn A. Maloney-Mújica

LSU Master's Theses

This study explores the factors associated with the implementation of land use planning policies and tools among the parishes (counties) of Louisiana. There is an absence of statutory standards, strict guidelines, and other external drivers for planning in Louisiana and the extent to which local governments regulate land use varies widely among local jurisdictions. The purpose of this study is to provide an empirical model of intrinsic factors that might explain why some parishes have decided to intervene in land use by adopting a high number of planning policies and tools, and why others have failed to adopt few, if …


An Evaluation Of The Perceived Obstacles For Policy Officials Regulating The Post Harvest Treatment Of Raw Oysters To Control The Human Health Vibrio Vulnificus Problem, Amy Leah Oestringer Jan 2008

An Evaluation Of The Perceived Obstacles For Policy Officials Regulating The Post Harvest Treatment Of Raw Oysters To Control The Human Health Vibrio Vulnificus Problem, Amy Leah Oestringer

LSU Master's Theses

Vibrio vulnificus is the leading pathogen linked to seafood-associated deaths. This naturally occurring marine bacterium presents a human health risk when it is consumed in raw oysters. Hospitalization is necessary in 90 % Vibrio vulnificus illnesses and 40% end in death. (CDC) Several guidelines and regulations have been enacted to combat this human health issue, but have failed to reduce the steadily rising illness rate. Post-harvest processing requirements for raw oysters could be used to reduce illness rates. A survey was conducted to measure the perceived obstacles that regulators and industry representatives of the raw oyster industry face in policymaking …


Design Of A Fully Autonomous Mobile Pipeline Exploration Robot (Famper), Jong-Hoon Kim Jan 2008

Design Of A Fully Autonomous Mobile Pipeline Exploration Robot (Famper), Jong-Hoon Kim

LSU Master's Theses

Pipelines have been an integral part of our constructions for many centuries. However, need to be maintained, and the cost of maintenance continues to increase. Robots have been considered as an attractive alternative, and many different types of pipeline robots have been proposed in the past. Unfortunately many of them work under only very restricted environments such as customized pipelines, often have no vertical mobility, or can traverse through only a simple pipeline structure due to wired control. This thesis presents the design and implementation of a robot based on novel idea we call “caterpillar navigational mechanism”. A Fully Autonomous …


Dynamic Workflow Management For Large Scale Scientific Applications, Emir Mahmut Bahsi Jan 2008

Dynamic Workflow Management For Large Scale Scientific Applications, Emir Mahmut Bahsi

LSU Master's Theses

The increasing computational and data requirements of scientific applications have made the usage of large clustered systems as well as distributed resources inevitable. Although executing large applications in these environments brings increased performance, the automation of the process becomes more and more challenging. The use of complex workflow management systems has been a viable solution for this automation process. In this thesis, we study a broad range of workflow management tools and compare their capabilities especially in terms of dynamic and conditional structures they support, which are crucial for the automation of complex applications. We then apply some of these …


Coarse Woody Debris Characteristics Of Managed And Unmanaged Bottomland Hardwood Forests, John Wesley Cochran Jan 2008

Coarse Woody Debris Characteristics Of Managed And Unmanaged Bottomland Hardwood Forests, John Wesley Cochran

LSU Master's Theses

Increasingly, attention is being paid to the role coarse woody debris (CWD) plays in forest ecosystems. CWD has been shown to provide valuable wildlife habitat, support food webs and contribute to nutrient storage and cycling, and mediate hydrological and geomorphic process. Timber management may be altering CWD dynamics by replacing aging stands with younger, more vigorous ones. The specific objectives of this study were 1) to quantify differences in coarse woody debris characteristics among bottomland hardwood forest stands with different management histories, and 2) to determine how differences in tree species composition and forest structure in bottomland hardwood forests influence …


Ethanol Production Using Continuous Multi-Staged Microbe Bioreactors: A Laboratory Study, William Bruce King Jan 2008

Ethanol Production Using Continuous Multi-Staged Microbe Bioreactors: A Laboratory Study, William Bruce King

LSU Master's Theses

Alternative fuels are important for the United States to reduce their dependence on fossil fuels. Currently, ethanol is the only renewable fuel that is produced in commercial quantity. The demand for ethanol is increasing throughout the world. The production of ethanol is limited by the available feedstocks and processing technology. Corn is the primary feedstock for ethanol in the United States. It is processed in either the wet milling or dry milling process. Both processes use either the batch or continuous fermentors. Both batch and continuous systems have operational restrictions with maintaining a good growth of yeast and preventing contamination …


Evaluating Ecological Equivalence In Created Marshes, Christopher Bromley Llewellyn Jan 2008

Evaluating Ecological Equivalence In Created Marshes, Christopher Bromley Llewellyn

LSU Master's Theses

The overall goal of coastal wetland restoration is to achieve ecological equivalence through the reproduction of structural and functional characteristics. This study sought to examine ecological equivalence using a chronosequence of temporal replicates of created marshes using traditional structural measures of equivalence and tested the use of stable isotopes as a measure of functional equivalence. The objectives of this study were to: (1) compare measures of structural equivalence at created and reference marshes; (2) use stable isotope analysis of blue crab muscle and hepatopancreas tissues to compare functional equivalence at created and reference marshes; and (3) determine if there is …


Measurement Of Nutrient Availability In Feedstuffs For Florida Pompano And Development Of Formulated Diets For Pompano Aquaculture, Craig Gothreaux Jan 2008

Measurement Of Nutrient Availability In Feedstuffs For Florida Pompano And Development Of Formulated Diets For Pompano Aquaculture, Craig Gothreaux

LSU Master's Theses

Consistently high market demand combined with low commercial catches have made Florida pompano, Trachinotus carolinus, one of the highest valued finfish from the Gulf of Mexico. Economic incentive has spurred interest in pompano culture since the 1950s, yet the body of nutritional research on pompano is still sparse. This study was conducted to measure the apparent digestibility of nutrients among a selection of common feed ingredients, and determine the optimum dietary protein level for juvenile Florida pompano at a fixed protein-to-energy ratio, in order to formulate nutritionally complete, cost-effective diets. The four ingredients tested in the digestibility trial were soybean …


Feasibility Testing For Salsa Neutrino Astrophysics Project, Jarrod Christopher Marsh Jan 2008

Feasibility Testing For Salsa Neutrino Astrophysics Project, Jarrod Christopher Marsh

LSU Master's Theses

Research is presented that was performed to determine possible locations for a full scale Salt Dome Shower Array (SalSA) neutrino telescope sensitive to energies from TeV ($10^{12}$ eV), PeV ($10^{15}$ eV), and EeV ($10^{18}$ eV) neutrinos. A detector to test possible site locations was designed around a half-Watt Ham radio to transmit short pulses of 145.500 MHz radiation. The research began by designing the system. Several phases of design took place as the system was refined and calibrated. Once finished, it was taken into a field and tested. The objective was to determine how the signals depended on distance. In …


Influences On Effective Local Wildfire Mitigation Programs, Kimberly Ann Geaghan Jan 2008

Influences On Effective Local Wildfire Mitigation Programs, Kimberly Ann Geaghan

LSU Master's Theses

The purpose of this research is to identify key components of community wildfire risk reduction programs and potential influences on the adoption of these program elements. Community wildfire programs have been developed to educate and encourage property owners to adopt “vegetation management” practices such as creating defensible space around structures, landscaping with fire-resistant plants, and removing potential wildfire fuels such as trees and shrubs. The analyses are based on a survey conducted by investigators from Louisiana State University in conjunction with the U.S. Forest Service. This survey was distributed to wildfire mitigation program managers listed on the National Wildfire Programs …


An Analysis Of The Benefits And Patterns Of Public Support For Urban Forestry Programs, Barbi Marisa Landano Jan 2008

An Analysis Of The Benefits And Patterns Of Public Support For Urban Forestry Programs, Barbi Marisa Landano

LSU Master's Theses

Trees are an essential element in a healthy urban community. They provide many benefits if they are properly managed and maintained throughout their lives. In order to accomplish this, urban forestry programs need to be established and there needs to be a good support system within the city. The objectives of this study are to identify key factors that may influence public support for urban forestry programs and to examine the role of nonprofit organizations in building support for and implementing urban forest programs. Surveys of Baton Rouge, Louisiana residents were conducted to identify the variables that are associated with …


Komatiitic Flows Of The Pioneer Ultramafic Complex Of The 3.3ga Weltevreden Formation, Barberton Greenstone Belt, South Africa: Stratigraphy, Petrology, And Geochemistry, Marc Romain Cooper Jan 2008

Komatiitic Flows Of The Pioneer Ultramafic Complex Of The 3.3ga Weltevreden Formation, Barberton Greenstone Belt, South Africa: Stratigraphy, Petrology, And Geochemistry, Marc Romain Cooper

LSU Master's Theses

The 3.29 Ga Pioneer Ultramafic Complex (WPC) is a 1 km thick east-northeast trending tilted (90° dip) section of layered ultramafic rock in the Weltevreden Formation in the west-northwest region of the Barberton Greenstone Belt (BGB). It was originally interpreted as an intrusive complex with slaty zones that have a linear horizontal fabric produced by shear. However, a recent study identifies these slaty zones as komatiitic tuffs and attributes their horizontal fabric to plane and cross bedding. The present study suggests the non-slaty zones are extrusive komatiitic flows with abundant pyroxene spinifex tops, normal volcanic textures and crystal sizes, and …


The Impacts Of River Impoundment: A Case Study Of H. Neely Henry Lake In Northeast Alabama, Willis Scott Estis Jan 2008

The Impacts Of River Impoundment: A Case Study Of H. Neely Henry Lake In Northeast Alabama, Willis Scott Estis

LSU Master's Theses

Dam building is one of the methods that modern civilization uses in an attempt to harness the power of nature. These dams and the impoundments associated with them can contribute numerous positive impacts to the surrounding human population. Unfortunately, there are negative impacts as well. This research focuses on one impoundment in particular, H. Neely Henry Lake in northeast Alabama (an impoundment of the Coosa River). Site-specific information regarding the H. Neely Henry development is explored including area geography, history, and the formation of the Alabama Power Company – the agency responsible for H. Neely Henry and other Coosa River …


Data Exploration By Using The Monotonicity Property, Hongyi Chen Jan 2008

Data Exploration By Using The Monotonicity Property, Hongyi Chen

LSU Master's Theses

Dealing with different misclassification costs has been a big problem for classification. Some algorithms can predict quite accurately when assuming the misclassification costs for each class are the same, like most rule induction methods. However, when the misclassification costs change, which is a common phenomenon in reality, these algorithms are not capable of adjusting their results. Some other algorithms, like the Bayesian methods, have the ability to yield probabilities of a certain unclassified example belonging to given classes, which is helpful to make modification on the results according to different misclassification costs. The shortcoming of such algorithms is, when the …


Effects Of Burning On Henslow's Sparrow (Ammodramus Henslowii) Density And Habitat Quality In Louisiana, Laura M. Palasz Jan 2008

Effects Of Burning On Henslow's Sparrow (Ammodramus Henslowii) Density And Habitat Quality In Louisiana, Laura M. Palasz

LSU Master's Theses

The Henslow’s Sparrow (Ammodramus henslowii) is a grassland species of concern that winters in prairies and open pine savannas across the Gulf Coastal Plain. Previous studies have indicated that these birds occur at higher densities in recently burned habitats in winter, but this has never been examined over a large geographic area containing multiple habitat types. The objectives of the study were to identify areas of important winter habitat in Louisiana, to examine the relationship between time since burn, bird density, and bird condition, and to determine vegetation structure and composition used by birds. We found most of the new …


Modeling And Design Of Low Cost Customizable Household Robot, Bharat Narahari Jan 2008

Modeling And Design Of Low Cost Customizable Household Robot, Bharat Narahari

LSU Master's Theses

Just as the growth of Personal computer, Mobile phones and Automobiles took place in last 3 decades, the personal robotics industry still in its nascent stage, is heading in the same direction. This thesis explores the concept of customizable household robots (CHR) in the robotics community. An attempt has been made to design a customizable robot by extending the 2 wheel differential drive kinematic model to 4 wheel independent differential drive kinematic model. A framework for CHR is developed which will be able to do various household repetitive tasks. Just as we can assemble a PC by buying its individual …


Non-Industrial Private Forest Landowners And Us Home Center Retailers' Attitudes And Perceptions Of Forest Certification, Polwattage Kushil Perera Jan 2008

Non-Industrial Private Forest Landowners And Us Home Center Retailers' Attitudes And Perceptions Of Forest Certification, Polwattage Kushil Perera

LSU Master's Theses

The concept of forest certification, a relatively recent development in forestry, is based on the use of market-based incentives to encourage sustainable forest management practices. Since the majority of forests in US South are privately owned, certifying forests owned by non-industrial private forest (NIPF) landowners is an important issue. From the demand perspective of certification, pressure from non-governmental environmental organizations and consumer awareness has prompted major wood products retailers to state preferences for certified wood products. In the US, wood product demand in the retail home centers sector is second only to the home building industry. In addition, home center …


Synthesis Of Disubstituted Amino Acids And Peptide Inhibitors Of Amyloid Beta Aggregation, Gregory Todd Mccandless Jan 2008

Synthesis Of Disubstituted Amino Acids And Peptide Inhibitors Of Amyloid Beta Aggregation, Gregory Todd Mccandless

LSU Master's Theses

The aggregation process of amyloid beta from monomeric peptide to oligomers and fibrils is believed to be connected with the neurological disorder Alzheimer’s disease. The focus of this research is the synthesis of alpha, alpha-disubstituted amino acids and peptide inhibitors of amyloid beta aggregation. The inhibitors are designed to interrupt (or alter) this process by binding to amyloid beta’s central hydrophobic core region (residues 17-20, Leucine-Valine- Phenylalanine-Phenylalanine). Target specificity is achieved via self recognition by basing the inhibitors on the sequence in this region. The inclusion of disubstituted amino acids in the sequence of the inhibitors will provide a blocking …


Pet/Ct Detectability And Classification Of Simulated Pulmonary Nodules Using An Suv Correction Scheme, Andrew Nicholas Morrow Jan 2008

Pet/Ct Detectability And Classification Of Simulated Pulmonary Nodules Using An Suv Correction Scheme, Andrew Nicholas Morrow

LSU Master's Theses

Positron emission tomography (PET) and computed tomography (CT) together are a powerful diagnostic tool, but imperfect image quality contributes to false positive and false negative diagnoses by an observer despite experience and training. This work investigated a PET standard uptake value (SUV) correction scheme, based on partial volume effect (PVE), on the classification of lesions as benign or malignant in PET/CT images. The correction scheme comprised several steps. The observer drew a region of interest (ROI) around the lesion using the CT dataset. The ROI was blurred with the assumed point spread function (PSF) of the PET scanner then re-sampled …


Land Use And Water Quality Characterization Of Boeuf Basin, La, Joseph Wesley Leblanc Jan 2008

Land Use And Water Quality Characterization Of Boeuf Basin, La, Joseph Wesley Leblanc

LSU Master's Theses

The three primary goals of this project were to establish the ambient background of water quality in the Lake Boeuf basin in southeast Louisiana; establish land use patterns in the basin and the relation to water quality; and develop a preliminary plan to improve water quality through the use of best management practices and wetland assimilation. Urban and agricultural acreage borders the basin and runoff from these lands forces loadings of nutrients into the adjacent canals where they become channelized and ultimately exit the Boeuf Basin into Lac des Allemandes. From September 2007 until February 2008, water sampling occurred monthly …


Failure-Awareness And Dynamic Adaptation In Data Scheduling, Mehmet Balman Jan 2008

Failure-Awareness And Dynamic Adaptation In Data Scheduling, Mehmet Balman

LSU Master's Theses

Over the years, scientific applications have become more complex and more data intensive. Especially large scale simulations and scientific experiments in areas such as physics, biology, astronomy and earth sciences demand highly distributed resources to satisfy excessive computational requirements. Increasing data requirements and the distributed nature of the resources made I/O the major bottleneck for end-to-end application performance. Existing systems fail to address issues such as reliability, scalability, and efficiency in dealing with wide area data access, retrieval and processing. In this study, we explore data-intensive distributed computing and study challenges in data placement in distributed environments. After analyzing different …


Late Quaternary Geochronologic, Stratigraphic, And Sedimentologic Framework Of The Trinity River Incised Valley: East Texas Coast, Matthew Gene Garvin Jan 2008

Late Quaternary Geochronologic, Stratigraphic, And Sedimentologic Framework Of The Trinity River Incised Valley: East Texas Coast, Matthew Gene Garvin

LSU Master's Theses

Optically stimulated luminescence dates from the last glacial period falling–stage and lowstand Deweyville deposits along the Trinity River valley in Texas provided insight to their timing of deposition and allogenic controls on fluvial processes. Three distinguishable periods of incision and lateral channelbelt migration were the effect of both lowered sea levels and climate controlling factors within the drainage basin. Valley widening and deposition of the High, Middle, and Low Deweyville units were constructed and subsequently preserved as fluvial terraces during oxygen isotope stages (OIS) 3 through 2, from 65–32.5 ka, 32.5–23 ka, and 23–16 ka respectively. Although numerous workers using …


Strategic Analysis Of Ghana's Wood Export Sector, Odoom Domson Jan 2008

Strategic Analysis Of Ghana's Wood Export Sector, Odoom Domson

LSU Master's Theses

Export-led strategies are very crucial to achieving growth and goals of developing and transition economies such as Ghana. As a result, export strategies are being adopted in many developing countries. Although such export strategies might be in place, the deployment of resources and tax payers’ money involved often calls for the investigation of programs and initiatives that exist and perceptions by industry if they are working. Furthermore, Ghana wood exports to the US, a historically major market, have been declining over the past six years. Therefore, there is the need to determine if export constraints to the US market exist. …


Evaluating The Economic And Environmental Impacts Of Water Subsidies In Kuwait, Mohammad Alshawaf Jan 2008

Evaluating The Economic And Environmental Impacts Of Water Subsidies In Kuwait, Mohammad Alshawaf

LSU Master's Theses

Kuwait and the other Gulf Cooperation Council (GCC) states have experienced rapid growth in population coupled with a rise in the standards of living and acceleration in social, agricultural, and industrial growths, which greatly increased the demand for water supplies. Due to the scarcity of water resources in the region, non-conventional water supplies such as seawater desalination are and have been the main water resource. Kuwait has so far been able to meet demand by using its access to both the sea and abundant oil needed in the desalination plants. The quantity of water consumed per capita in Kuwait is …