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Physical Sciences and Mathematics

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2006

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Breeding Waterbird Use Of Rice Fields In Southwestern Louisiana, Sergio Pierluissi Jan 2006

Breeding Waterbird Use Of Rice Fields In Southwestern Louisiana, Sergio Pierluissi

LSU Master's Theses

Rice fields are agricultural wetlands concentrated in several areas in the U.S., including southwestern Louisiana. Rice fields are flooded for much of the year and support thick emergent vegetation, potentially providing high-quality habitat for several species of breeding waterbirds. The objectives of this study were to (1) determine relative nest density, nest success, and habitat associations of breeding waterbirds in southwestern Louisiana rice fields and (2) determine the effectiveness of callback surveys as a monitoring tool. In the summers of 2004 and 2005, marsh bird surveys and nest searches were conducted in Cameron, Jefferson Davis, Vermilion, and Acadia Parishes in …


Effects Of Insectivorous Birds On Tree Growth In The Maurepas Swamp, David M. Fox Jan 2006

Effects Of Insectivorous Birds On Tree Growth In The Maurepas Swamp, David M. Fox

LSU Master's Theses

Coastal forests in Louisiana are in decline due to natural and human caused changes in the hydrology of the region. Baldcypress and water tupelo trees have been further stressed by caterpillar herbivory in recent decades. Regeneration of water tupelo is crucial for cavity creation for nesting habitat for secondary cavity nesting bird populations. Insectivorous birds have been shown to decrease insect-caused leaf damage on trees in other ecosystems. Two experiments examining effects of insectivorous birds on tree growth were conducted in degraded areas of the Maurepas Swamp in southeastern Louisiana. In the first experiment, nest boxes were added to study …


Muscovite Pseudomorphs After Staurolite As A Record Of Fluid Infiltration During Prograde Metamorphism, Jennifer Kaye Whittington Jan 2006

Muscovite Pseudomorphs After Staurolite As A Record Of Fluid Infiltration During Prograde Metamorphism, Jennifer Kaye Whittington

LSU Master's Theses

Pressure-temperature conditions encountered by metamorphic rocks are often used to constrain tectonic environments of formation. Evidence of the prograde path during metamorphism is often obliterated by peak metamorphic conditions. However, pseudomorphs that form during prograde metamorphism may provide insights into heat and mass transport along this portion of the P-T-X-t path. Seventeen sillimanite zone samples, each containing 2-5 muscovite-rich pseudomorphs after staurolite, were investigated from pelitic schists of the Farmington Quadrangle, west-central Maine, USA. Pseudomorphs are easily recognized by an increase in average grain size (~cm) and change to randomly oriented muscovite-rich (~45-75%) modal mineralogy relative to the rock matrix …


Effects Of Terraces On Submerged Aquatic Vegetation In Shallow Marsh Ponds In Coastal Southwest Louisiana, Christopher Dean Cannaday Jan 2006

Effects Of Terraces On Submerged Aquatic Vegetation In Shallow Marsh Ponds In Coastal Southwest Louisiana, Christopher Dean Cannaday

LSU Master's Theses

The wetlands of coastal Louisiana are disappearing at a rate of 65 to 80 km2yr-1. Most of the loss is the conversion of emergent marsh to shallow marsh ponds. Terracing is one restoration technique that has been used frequently in recent years. Terraces are small intertidal ridges built in shallow marsh ponds to reduce wave action. It is assumed that this will slow erosion of adjacent emergent marsh and increase Submerged Aquatic Vegetation (SAV) production, a key habitat component for many marsh fauna. Yet both relevant previous studies failed to show that terraces increased SAV abundance. …


Investigation Of The Structure In Electrodeposited Nanostructured Co/Cu Alloys, Multilayers, And Cofe/Cu Multilayered Nanowires, Erick Jamal Lawson Jan 2006

Investigation Of The Structure In Electrodeposited Nanostructured Co/Cu Alloys, Multilayers, And Cofe/Cu Multilayered Nanowires, Erick Jamal Lawson

LSU Master's Theses

Since the discovery of giant magnetoresistance (GMR) in electrodeposited nanostructured magnetic multilayers and multilayered nanowires, there has been interest throughout the scientific world in the fabrication and characterization of these materials. Magnetic multilayers in the form of thin films can be used as magnetoresistive sensors in the magnetic data storage industry. Arrays of nanowires have the potential for applications in perpendicular ultra-high density data storage and biosensors. Wire-shaped magnetic multilayered nanowires have been shown to exhibit GMR in the so called “current perpendicular-to plane” configuration (CPP-GMR). GMR of multilayers and multilayered nanowires have been investigated in several systems that include …


Use Of Atomic Force Microscopy To Study A Molecular Micelle As An Anionic Polymer For Polyelectrolyte Multilayer Deposition On Polymeric Substrates, Angela Nakeeta Douglas Jan 2006

Use Of Atomic Force Microscopy To Study A Molecular Micelle As An Anionic Polymer For Polyelectrolyte Multilayer Deposition On Polymeric Substrates, Angela Nakeeta Douglas

LSU Master's Theses

Polyelectrolyte multilayers (PEMs) have been used as stationary phases for various chiral and achiral separations in open-tubular electrochromatagraphy (OT-CEC). However, the physical characteristics of PEMs are not well understood. The production of PEM coatings involves flowing alternating rinses of positive and negative charged polyelectrolytes onto a surface. Although PEMs are typically deposited on fused silica capillaries, there is growing interest to use this approach in conjunction with microchip devices to enhance separation characteristics. Since microchips are fabricated using polymeric substrates, the deposition of PEMs on these substrates needs to be examined. The study reported in this thesis uses atomic force …


Winter Diet, Seed Preferences And Foraging Behavior Of Henslow's Sparrows (Ammodramus Henslowii) In Southeastern Louisiana, Jennifer K. Dimiceli Jan 2006

Winter Diet, Seed Preferences And Foraging Behavior Of Henslow's Sparrows (Ammodramus Henslowii) In Southeastern Louisiana, Jennifer K. Dimiceli

LSU Master's Theses

Henslow's Sparrow (Ammodramus henslowii) is a grassland bird whose population is declining throughout its range, mainly due to habitat loss. The Longleaf Pine forest ecosystems in which Henslow's Sparrows spend their winters are reduced to 5% of their former range. The winter ecology of Henslow's Sparrow remains understudied, especially regarding important aspects of diet and foraging behavior. To determine winter diet, I collected fecal samples from Henslow's Sparrows during banding operations in southeastern Louisiana pine savannas from October 2003-March 2004 and October 2004-April 2005. I then analyzed the samples for presence of seeds and arthropod parts, identified them to the …


Dendrochronological Analysis Of Productivity And Hydrology In Two Louisiana Swamps, John Blake Amos Jan 2006

Dendrochronological Analysis Of Productivity And Hydrology In Two Louisiana Swamps, John Blake Amos

LSU Master's Theses

Modified river flows and land subsidence have subjected many coastal swamp forests in the delta of the Mississippi River to greatly altered flooding, sediment, and nutrient regimes. These areas have become inundated to greater depth, duration, and frequency and either are connected to the river and receive drastically increased sediment and nutrients (riverine swamps) or have become disconnected from riverine flooding (stagnant swamps) and receive little or no sediment and nutrient input. To better understand how these changes are affecting ecosystems, dendrochronological techniques for baldcypress (Taxodium distichum L. Rich.) were used at three sites in each of two contrasting swamps …


Application Of Short-Term Sediment Dynamics And Particle-Bound Phosphorus Fractionation Methods (Sedex) To Estimate The Benthic Nutrient Loading Potential In Upper Newport Estuary, California, Hilary Amanda Collis Jan 2006

Application Of Short-Term Sediment Dynamics And Particle-Bound Phosphorus Fractionation Methods (Sedex) To Estimate The Benthic Nutrient Loading Potential In Upper Newport Estuary, California, Hilary Amanda Collis

LSU Master's Theses

Estuaries act as sources, sinks, and biogeochemical transformation sites for natural and anthropogenically-derived nutrients. Sediment loading from watersheds provides an important source of particulate nutrients to estuaries often neglected when constructing nutrient budgets. Deposition and resuspension of these sediments are known to impact biogeochemical cycles in estuarine environments. Phosphorus (P) exists in many forms in aquatic environments, and increased P loading to coastal environments increases primary productivity potentially leading to eutrophication. Magnitude and variability of sediment deposition, resuspension, and sediment-bound P concentrations were evaluated in Upper Newport Bay (UNB), California. During 2004, seven push cores were collected from the intertidal …


Tomotherapy For Post-Mastectomy Radiotherapy (Pmrt): Comparison With Conventional Electron Beam Technique, Michael Sissay Ashenafi Jan 2006

Tomotherapy For Post-Mastectomy Radiotherapy (Pmrt): Comparison With Conventional Electron Beam Technique, Michael Sissay Ashenafi

LSU Master's Theses

Purpose: TomoTherapy, capable of delivering intensity-modulated, image-guided radiotherapy with a helical fan-beam, multileaf-collimated beam and detector array mounted on a CT ring, is challenging the treatment techniques commonly used in today's radiotherapy clinic. The present works investigates the potential of using TomoTherapy in lieu of electron beams for treatment of the chest wall in post-mastectomy radiotherapy (PMRT). It is hypothesized that TomoTherapy can plan dose distributions for PMRT patients, that a pre-selected radiation oncologist judges to be equal to or better than that of a conventional plan treated with electron beams. Methods: A patient database of retrospective conventional PMRT treatment …


Using Life-History, Surplus Production, And Individual-Based Population Models For Stock Assessment Of Data-Poor Stocks: An Application To Small Pelagic Fisheries Of The Lingayen Gulf, Philippines, Ronald B. Lachica Jan 2006

Using Life-History, Surplus Production, And Individual-Based Population Models For Stock Assessment Of Data-Poor Stocks: An Application To Small Pelagic Fisheries Of The Lingayen Gulf, Philippines, Ronald B. Lachica

LSU Master's Theses

Stock assessment methods that quantify the status of fishery resources are critical to effective fisheries management. There is a need for stock assessment methods applicable for management of tropical species based on limited, un-aged catch data. I applied four stock assessment approaches to situation with limited life-history information and with short-term, un-aged catch data. The four approaches are: life-history invariants, length-based catch analysis, individual-based modeling, and surplus production modeling. All four approaches were applied to catch data from Lingayen Gulf, Philippines. The life-history invariant, length-based catch analysis, and individual-based modeling were applied to monthly length-frequency data of commercial catch for …


Ice Sheet Grounding Zone Deposits On Ross Sea Continental Shelf (Antarctica): Seismic Facies Analysis And P-Wave Reflectivity Attributes, Adeniyi Adewumi Saanumi Jan 2006

Ice Sheet Grounding Zone Deposits On Ross Sea Continental Shelf (Antarctica): Seismic Facies Analysis And P-Wave Reflectivity Attributes, Adeniyi Adewumi Saanumi

LSU Master's Theses

Subglacial till and overlying glaciomarine deposits are difficult to distinguish because the physical properties of subglacial till may vary depending on the drainage conditions of the rock directly beneath the ice sheet. Based on approximately 120 kilometers of multi-channel seismic data, detailed seismic facies analysis and amplitude variation with offset (AVO) analysis are carried out to examine the distribution of ice sheet grounding zone deposits on the continental shelf of the Northern Basin, Ross Sea (Antarctica) and infer the physical properties of interpreted subglacial till. Seismic facies analysis led to the differentiation of distinct sub-environments around a grounded ice sheet: …


Computer-Aided Diagnostic Systems For Digital Mammograms, Nicholas Jabari Lee Jan 2006

Computer-Aided Diagnostic Systems For Digital Mammograms, Nicholas Jabari Lee

LSU Master's Theses

A computer-aided diagnostic (CAD) system that uses a unique shape-based classification scheme, the Ellipse-Closed Curve Fitting (ECCF) algorithm, is developed for digital mammogram image analysis. The system is developed to work as a post-processing extension to a previously developed CAD system that locates and segments mass lesions, or tumors, found in digital mammograms into separate images. The ECCF system is implemented in the MATLAB mathematical scripting language and is thus capable of running on multiple platforms. The ECCF algorithm detects edges in tumor images and casts them into closed curve functions. Parameters for an ellipse of best fit for a …


Electronic Mathematics, Aidan O'Donoghue Jan 2006

Electronic Mathematics, Aidan O'Donoghue

Theses

Recent times have seen an explosion in the use of interactive technologies in the delivery of learning content to students in all educational sectors in Ireland. This expansion has led to the creation of modem day phenomenons such as global and ‘teacherless’ classrooms.

The research study I have undertaken is to determine if students perform to the same standard when learning through an interactive educational software application as opposed to a more traditional setting of learning ’through’ a teacher in a classroom. The application being developed for this study enables students to learn the ordinary level leaving certificate mathematics course …


Patterns Of Total Suspended Solids Concentration And The Influence Of Antecedent Conditions On Hydrograph Response To Precipitation Events On Beaver Creek, Ontario, Matthew Peter Roy Mittler Jan 2006

Patterns Of Total Suspended Solids Concentration And The Influence Of Antecedent Conditions On Hydrograph Response To Precipitation Events On Beaver Creek, Ontario, Matthew Peter Roy Mittler

Theses and Dissertations (Comprehensive)

This study explored relationships between suspended solids concentration and discharge, the influence of antecedent conditions on event hydrograhs and the state of dynamic equilibrium in a second-order stream (Beaver Creek), draining an agricultural basin in southern Ontario, near the City of Waterloo. Beaver creek was monitored for nineteen weeks from July to November of 2005. Thirteen precipitation events of various magnitude and duration were examined within the study period. Discharge and total suspended soils were sampled throughout the events. Cross sectional profiles of six transects were measured prior to and after each event. Base flow, antecedent conditions and event response …


Seasonal Variability Of Carbon Dioxide Fluxes Over A Heterogeneous Low Tundra Ecosystem, Ronald P. Van Haarlem Jan 2006

Seasonal Variability Of Carbon Dioxide Fluxes Over A Heterogeneous Low Tundra Ecosystem, Ronald P. Van Haarlem

Theses and Dissertations (Comprehensive)

The seasonal carbon dioxide (CO2) budget and its associated environmental controlling parameters, soil moisture, soil temperature and depth to frost were investigated throughout the growing period during the summer of 2004. The study site is located within the low arctic tundra environment at Daring Lake, NWT (62⁰52’N, 111⁰35’W). The CO2 fluxes from an area of heterogeneous tundra composition were intensely monitored. The net seasonal CO2 budget was approximated to be 10.2 g C-CO2 m-2 for 100 days (DOY 159-259) of the 2004 snow-free study period. The CO2 flux dynamic was found to differ between 4 identified seasonal periods—melt, pre-green, green …


Petrological And Geochemical Investigations Of Deep Sea Turbidite Sands In The Pandora And Moresby Troughs: Source To Sink Papua New Guinea Focus Area, Luke Jeremiah Patterson Jan 2006

Petrological And Geochemical Investigations Of Deep Sea Turbidite Sands In The Pandora And Moresby Troughs: Source To Sink Papua New Guinea Focus Area, Luke Jeremiah Patterson

LSU Master's Theses

The Moresby and Pandora Troughs of the northern Coral Sea are components of the deep-sea depositional system that is the ultimate sink for the Source to Sink Papua New Guinea (PNG) Focus Area. Cores collected from the R/V Melville during March-April 2004 reveal marine volcaniclastic and terrigenous turbidites deposited in these troughs during the Quaternary. Constraining the spatial, temporal, and provenance characteristics for these terrigenous sands through mineralogical, chemical, and textural analysis is the primary focus of this study. All cores contain thinly-bedded sandy turbidite packages interlayered with hemipelagic marls and typical centimeter-to-meter-thick turbidite sequences. The Moresby Trough core JPC22 …


Caliche As A Geologic Repository For Atmospheric Sulfate, Katie Jane Howell Jan 2006

Caliche As A Geologic Repository For Atmospheric Sulfate, Katie Jane Howell

LSU Master's Theses

Recent studies demonstrate that important information on sulfur source, oxidation pathway, transport pattern, and reaction kinetics of the oxidation reactions of reduced sulfur gases in the atmosphere may be uncovered by measuring multiple sulfur and oxygen isotope compositions of the oxidation product — secondary atmospheric sulfate (SAS). SAS from Earth’s distant past, however, is rarely preserved in the rock record because of its high solubility and small quantity. Caliche, a pedogenic carbonate formed in arid to semi-arid continental settings and common in the geologic record, could serve as a repository for ancient SAS. Two major groups of caliche samples: 1) …


Impacts Of Red Imported Fire Ants (Solenopsis Invicta Buren) On Native Faunal Communities In Two Pine-Dominated Forests, Lee A. Womack Jan 2006

Impacts Of Red Imported Fire Ants (Solenopsis Invicta Buren) On Native Faunal Communities In Two Pine-Dominated Forests, Lee A. Womack

LSU Master's Theses

Impacts red imported fire ants (RIFA) exert on native faunal communities were monitored in two pine-dominated ecosystems in Louisiana. After suppression of established RIFA populations with Amdro®, cotton mice (Peromyscus gossypinus), herpetofaunal, ground-dwelling invertebrate, Lycosidae, and non-target ant communities were compared between untreated-control and treated plots with respect to possible ecological impacts of RIFA on these communities. Efficacy of Amdro® (A. I. 0.7% hydramethylnon) was tested at Alexander State Forest and Sandy Hollow WMA, and was found to be effective at both sites for 99-42.3% and 97-48%, respectively, suppression of RIFA on treated plots, for three to seven months, with …


Salt Marsh Restoration With Sediment-Slurry Amendments Following A Drought-Induced, Large-Scale Disturbance, Angela Marie Schrift Jan 2006

Salt Marsh Restoration With Sediment-Slurry Amendments Following A Drought-Induced, Large-Scale Disturbance, Angela Marie Schrift

LSU Master's Theses

A large-scale, drought-induced disturbance occurred in Louisiana during the spring and summer of 2000. Approximately 100,000 acres of Spartina dominated marshes died-back and turned brown. This die-off caused considerable concern because in the absence of recovery dieback marshes can transform to mudflats, which can subside leading to open ponds. The state of Louisiana is attempting to restore some of the dieback marshes through the addition of sediment-slurries. The sediment-slurry generated significantly different marsh elevations: high elevation (mean and 95 % confidence interval: 29, 26 to 32 cm above ambient marsh), medium elevation (21, 19 to 24 cm), low elevation (14, …


Links Between Environmental Mercury, Special Education, And Autism In Louisiana, Jessica Rury Jan 2006

Links Between Environmental Mercury, Special Education, And Autism In Louisiana, Jessica Rury

LSU Master's Theses

The number of children born every year with neurological disorders is increasing and some of this increase may be attributed to mercury exposure. Pregnant women ingest contaminated fish, which transfers high mercury concentrations to the unborn fetus. This exposure may result in methyl mercury buildup in the brain of the unborn fetus. Symptoms ranging from minor to severe may be observed as special educational needs in school systems. These include learning disorders, developmental delays, and autism. Louisianans are especially susceptible to mercury contamination because fish and shellfish are a major portion of their cultural diet. This study, through the use …


Evaluation Of Tcp Based Congestion Control Algorithms Over High-Speed Networks, Yaaser Ahmed Mohammed Jan 2006

Evaluation Of Tcp Based Congestion Control Algorithms Over High-Speed Networks, Yaaser Ahmed Mohammed

LSU Master's Theses

The Additive Increase Multiplicative Decrease (AIMD) algorithm of the Transport Control Protocol (TCP) had worked remarkably well over low speed networks and had guaranteed fairness to the users all over these years, but at present, the demands for transferring large quantities of data over very high-speed networks are increasing at a tremendous rate. Because of its AIMD algorithm to control its window growth function accompanied by a slow response function which is inadequate over high-speed links, TCP has been proven to underutilize the available network bandwidth and leave a considerable amount of unused bandwidth. To overcome this limitation of TCP, …


Coastal Marsh Restoration Using Terraces: Effects On Waterbird Habitat In Louisiana's Chenier Plain, Jessica L. O'Connell Jan 2006

Coastal Marsh Restoration Using Terraces: Effects On Waterbird Habitat In Louisiana's Chenier Plain, Jessica L. O'Connell

LSU Master's Theses

Terracing is a novel technique used to combat coastal marsh loss in Louisiana and Texas. Terraces are assumed to slow marsh erosion, decrease pond depth, and encourage vegetation expansion. Terraced ponds have never been evaluated as habitat for waterbirds, which heavily depend on Louisiana�s coastal marshes. From April 2005 to April 2006, I monitored waterbird species richness and density through time to estimate effects that terracing has on habitat quality. Water quality (turbidity, salinity, conductivity, water temperature, and water depth) also was measured. Submerged aquatic vegetation (SAV) biomass and nekton density were measured from April 2005 to September 2005. I …