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Full-Text Articles in Physical Sciences and Mathematics

Plankton Community Respiration And Productivity For The Louisiana Offshore Ecosystem, July 2007 Results, Brandon Michael Boyd Oct 2010

Plankton Community Respiration And Productivity For The Louisiana Offshore Ecosystem, July 2007 Results, Brandon Michael Boyd

Honors Theses

No abstract provided.


Semi-Classical Approaches To Below Threshold Harmonics, James A. Hostetter May 2010

Semi-Classical Approaches To Below Threshold Harmonics, James A. Hostetter

Honors Theses

No abstract provided.


Hurricane Katrina And The Haitian Earthquake: Appeals For Social Responsibility In Governmental Emergency Management, Shawn Lin May 2010

Hurricane Katrina And The Haitian Earthquake: Appeals For Social Responsibility In Governmental Emergency Management, Shawn Lin

Honors Theses

No abstract provided.


A Discrete Nonlinear Model Of Resonant Scattering, Katherine Hollister Smith Apr 2010

A Discrete Nonlinear Model Of Resonant Scattering, Katherine Hollister Smith

Honors Theses

No abstract provided.


Method Of Riemann Surfaces In Modelling Of Cavitating Flow, Anna Zemlyanova Jan 2010

Method Of Riemann Surfaces In Modelling Of Cavitating Flow, Anna Zemlyanova

LSU Doctoral Dissertations

This dissertation is concerned with the applications of the Riemann-Hilbert problem on a hyperelliptic Riemann surface to problems on supercavitating flows of a liquid around objects. For a two-dimensional steady irrotational flow of liquid it is possible to introduce a complex potential w(z) which allows to apply the powerful methods of complex analysis to the solution of fluid mechanics problems. In this work problems on supercavitating flows of a liquid around one or two wedges have been stated. The Tulin single-spiral-vortex model is employed as a cavity closure condition. The flow domain is transformed into an auxiliary domain with known …


Synthesis And Characterization Of Rare Earth-Nickel-Gallium Ternary Intermetallics, Kandace R. Thomas Jan 2010

Synthesis And Characterization Of Rare Earth-Nickel-Gallium Ternary Intermetallics, Kandace R. Thomas

LSU Doctoral Dissertations

The structural and physical characterization of several early and latter rare earth Ln-Ni-Ga systems, which include Ln2NiGa12 (Ln = Pr, Nd, Sm), alpha-LnNiGa4 (Ln = Y, Gd – Yb) and beta-LnNiGa4 (Ln = Tb – Ho) will be presented in this work. These systems are thermodynamically located within a copious, robust phase space and provide a rich understanding of how slight modifications to synthetic preparations can yield the adoption of different structure types in a Ga-rich regime. Each of these phases is made up of well-studied substructures which lend an additional angle of apperception as to how their structure and …


Public Perception Of Wildfire Risk And Prescribed Burning In The Wildland/Urban Interface Of The Louisiana Florida Parishes, Charlotte Ann Gerald Jan 2010

Public Perception Of Wildfire Risk And Prescribed Burning In The Wildland/Urban Interface Of The Louisiana Florida Parishes, Charlotte Ann Gerald

LSU Master's Theses

Wildfire has been suppressed in the nation’s forests for over a hundred years. The accumulation of forest fuels over time has created an urgent need to reduce fuel loads to prevent catastrophic wildfires from occurring, not only in our wildlands, but also in our Wildland/Urban Interfaces (WUI’s). The residents who live within the WUI are particularly vulnerable to extreme wildfire events. As cities become more densely populated, increasing numbers of people are moving beyond the suburbs into the WUI. A complex matrix of structures and forested land, developing communities, and impinging forests exists within the WUI. This study utilized a …


Using Inoceramid Bivalve Taphonomy As A Paleoenvironmental Indicator Across The Cenomanian/Turonian Horizon At The Pueblo, Colorado Gssp, Jacob Frederick Grosskopf Jan 2010

Using Inoceramid Bivalve Taphonomy As A Paleoenvironmental Indicator Across The Cenomanian/Turonian Horizon At The Pueblo, Colorado Gssp, Jacob Frederick Grosskopf

LSU Master's Theses

Recent paleoenvironmental and geochemical studies indicate that benthic conditions during Oceanic Anoxic Event II (OAE II) (93.5 Mya) in the Cretaceous Interior Seaway (CIS) were dysoxic rather than anoxic. In this thesis, dysoxic benthic conditions were tested for by observing patterns in taphonomic alteration of the calcite portions of inoceramid bivalve shells during and after OAE II. Inoceramid valves were extracted from beds that spanned OAE II at the Cenomanian/Turonian Global Boundary Stratotype Section and Point (GSSP) in Pueblo, Colorado: beds 62 (Hartland Shale), 72 (Bridge Creek Limestone), and 115 (Bridge Creek Limestone). Degree of alteration was tallied using categorical …


Speciation Of Heavy Metals In Disturbed And Undisturbed Sediments From Atchafalaya Bay, Houma Navigation Canal, And Southwest Pass, Louisiana, Amanda Jo Zimmerman Jan 2010

Speciation Of Heavy Metals In Disturbed And Undisturbed Sediments From Atchafalaya Bay, Houma Navigation Canal, And Southwest Pass, Louisiana, Amanda Jo Zimmerman

LSU Master's Theses

In coastal Louisiana it is common to use dredge spoil to build marshland that has been lost due to a variety of factors. Under various conditions such as deposition in a drained oxygenated environment, metals in the spoil can become more bioavailable posing a threat to the ecosystem. This study compares metal availability in natural and dredged sediments to determine what changes occur in nature. Forty four samples from three locations, Atchafalaya Delta, Houma Navigation Canal, and Southwest Pass, were analyzed for 13 common elements with known or potentially harmful health effects; Al, As, Ba, Be, Cd, Cr, Co, Cu, …


Multigrid Methods For Maxwell's Equations, Jintao Cui Jan 2010

Multigrid Methods For Maxwell's Equations, Jintao Cui

LSU Doctoral Dissertations

In this work we study finite element methods for two-dimensional Maxwell's equations and their solutions by multigrid algorithms. We begin with a brief survey of finite element methods for Maxwell's equations. Then we review the related fundamentals, such as Sobolev spaces, elliptic regularity results, graded meshes, finite element methods for second order problems, and multigrid algorithms. In Chapter 3, we study two types of nonconforming finite element methods on graded meshes for a two-dimensional curl-curl and grad-div problem that appears in electromagnetics. The first method is based on a discretization using weakly continuous P1 vector fields. The second method uses …


Spatial Variations Of Salinity, Temperature And Pressure On The Flank Of A Salt Dome, Offshore Louisiana: Implications For Mechanisms Of Fluid Flow, Andrew Kevin Steen Jan 2010

Spatial Variations Of Salinity, Temperature And Pressure On The Flank Of A Salt Dome, Offshore Louisiana: Implications For Mechanisms Of Fluid Flow, Andrew Kevin Steen

LSU Master's Theses

Salt dome dissolution in the Gulf of Mexico sedimentary basin is a primary cause for elevated pore water salinities in the subsurface. Temperature, pressure, salinity, lithology and fluid density are parameters often used to identify preferential conduits and driving forces for fluid migration. These parameters were calculated using 20 wireline logs covering 40 km² on the south flank of a salt dome on the continental shelf, offshore Louisiana. 3-D seismic has been utilized to determine location of faults, to aid in sand correlation, and to provide a structural overview of the dome. Vertical and lateral variations in lithology, salinity, temperature, …


A Functional And Ontogenetic Skull Analysis Of The Extant Rhinoceroses And Teleoceras Major, An Extinct Miocene North American Rhinoceros, Mark Daniel Hagge Jan 2010

A Functional And Ontogenetic Skull Analysis Of The Extant Rhinoceroses And Teleoceras Major, An Extinct Miocene North American Rhinoceros, Mark Daniel Hagge

LSU Master's Theses

Functional and ontogenetic skull differences among extant rhinoceroses and the extinct North American rhinoceros Teleoceras major were investigated to assess the unknown feeding ecology of Teleoceras. Ontogenetic skull sequences of the extant Indian rhino (Rhinoceros unicornis), Sumatran rhino (Dicerorhinus sumatrensis), white rhino (Ceratotherium simum), and black rhino (Diceros bicornis), and the extinct Miocene North American rhino T. major were gathered for both qualitative and quantitative assessments. Eleven functional characters related to specific feeding ecologies in extant perissodactyls were morphologically described, and each species’ skull development was described in detail. Nineteen linear skull measurements were taken across all specimens of all …


Oxidation Of Reduced Sulfur Compounds: A Triple-Oxygen-Isotope Perspective, Issaku E. Kohl Jan 2010

Oxidation Of Reduced Sulfur Compounds: A Triple-Oxygen-Isotope Perspective, Issaku E. Kohl

LSU Doctoral Dissertations

The Earth’s geochemical evolution is recorded in the rocks that compose its lithosphere. Specifically, sulfate minerals have been identified as being repositories of information concerning the past hydrosphere, atmosphere and biosphere. This is due to the non-labile nature of SO42- and its ability to store a record of the oxidative reactions and oxygen sources involved in its formation. Microbial dissimilatory sulfate reduction (MDSR) and sulfide oxidation cause oxygen from H2O and O2 to be trapped to varying degrees in ambient, dissolved SO42-. In order to better interpret the H2O and O2 signals in SO42-, we must deepen our understanding of …


Geological Analysis And Hydrodynamic Modeling Of Tropical Cyclone Influence: Northeastern Gulf Of Mexico Inner Shelf, Amy Lynn Spaziani Jan 2010

Geological Analysis And Hydrodynamic Modeling Of Tropical Cyclone Influence: Northeastern Gulf Of Mexico Inner Shelf, Amy Lynn Spaziani

LSU Master's Theses

The need to characterize offshore resources as borrow areas for beach restoration has initiated interest of the impact of storms to the inner continental shelf. While numerous studies have investigated the response of coastal systems to major storms, very little is known about the geological response of inner shelves to frequent and intense storms. This approach integrated a geological study with modeling of hydrodynamics during recent storms, in order to relate trends in the geological signature to physical forcing mechanisms during storms. First, waves and hydrodynamic conditions were modeled during two major recent storms that made landfall in the northeastern …


The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim De Mutsert Jan 2010

The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim De Mutsert

LSU Doctoral Dissertations

A current method to restore Louisiana’s estuaries includes reintroducing freshwater and sediments to wetlands that are hydrologically isolated from the Mississippi River due to the construction of levees. In this dissertation, I examined effects of the second largest freshwater diversion in Louisiana, the Caernarvon Freshwater Diversion (CFD), on estuarine nekton in Breton Sound. Before focusing on Breton Sound, I examined the status of nekton communities in the northern Gulf of Mexico (GOM), and Louisiana wetlands in particular, using the mean trophic level index (MTLI). I demonstrated that commercial targeting caused the previously reported low and declining MTLI from the GOM. …


Computer Simulation Of Ion-Induced Nucleation In The Presence Of Single Ions And Ion Pairs, Samuel Keasler Jan 2010

Computer Simulation Of Ion-Induced Nucleation In The Presence Of Single Ions And Ion Pairs, Samuel Keasler

LSU Doctoral Dissertations

Atmospheric aerosol particles play an important role in climate and human health. Despite their importance, the mechanisms of their formation are still poorly understood. Ion-induced nucleation may play a role in the process, but details are lacking about how the nucleation rate depends on the size, charge, and number of ions in the cluster. In order to better understand the role that ions might play in new particle formation, we have performed a series of AVUS-HR simulations of the water nucleation in the presence of both single ions and ion pairs. These simulations have shown that the location of the …


Dissolution Of Chitosan In Ionic Liquids For Acylation Chemistry And Formation Of Cellulose-Chitosan Blends, Cristina Stefanescu Jan 2010

Dissolution Of Chitosan In Ionic Liquids For Acylation Chemistry And Formation Of Cellulose-Chitosan Blends, Cristina Stefanescu

LSU Doctoral Dissertations

Dissolution of chitosan in ionic liquids was accomplished. It has been shown that 1-butyl-3-methylimidazolium acetate (BMIMAc) is a better solvent than 1-butyl-3-methylimidazolium chloride (BMIMCl). Dissolution of chitosan in BMIMCl required a prior regeneration of chitosan from 1% acetic acid solution. In the case of BMIMAc, both dried chitosan and regenerated chitosan from acetic acid solution have been dissolved in a relatively short amount of time. While concentrations up to 2 wt% of chitosan in BMIMCl could be obtained, concentrations of 10 wt % of chitosan in BMIMAc were realized. Homogeneous phthalation and benzoylation of chitosan were achieved in these ionic …


Taphonomy And Sedimentology Of Two Miocene Vertebrate Fossil Sites On Fort Polk, Louisiana, Julie Lynn Hill Jan 2010

Taphonomy And Sedimentology Of Two Miocene Vertebrate Fossil Sites On Fort Polk, Louisiana, Julie Lynn Hill

LSU Master's Theses

The discovery of a terrestrial mammalian fauna in the Miocene deposits on Fort Polk, Louisiana, fills a geographic gap in the Gulf Coast paleontological framework, but the provenance of the fossils, nature of the depositional environments, and relationships between the sites is still debated. This is especially true for the TVOR site cluster. TVOR SE has a mixture of marine and terrestrial vertebrates in association with a partly dissolved, in situ bed of articulated oyster shells, which stands in contrast to the fully terrestrial and freshwater assemblage at TVOR, and the indeterminate site TVOR S. Although limited outcrop may bias …


The Impact Of Hurricanes Katrina And Rita On The Louisiana Judicial System, Charles Simon Mccowan, Iii Jan 2010

The Impact Of Hurricanes Katrina And Rita On The Louisiana Judicial System, Charles Simon Mccowan, Iii

LSU Master's Theses

This thesis is a case study of the impact of Hurricanes Katrina and Rita on the Louisiana court system and the response of the court system to the aftermath of these two hurricanes. Although this thesis focuses on one state’s court system’s response to two natural disasters, the research, conclusions and recommendations are transferable to other states. Hurricanes Katrina and Rita struck the Gulf Coast in 2005 devastating large areas in Louisiana, Texas, Mississippi and Alabama. Millions of people, including judges and attorneys, were forced to evacuate their homes, courts and law offices. The Hurricanes caused interruptions to both federal …


Implementation And Analysis Of A Top-K Retrieval System For Strings, Sabrina Chandrasekaran Jan 2010

Implementation And Analysis Of A Top-K Retrieval System For Strings, Sabrina Chandrasekaran

LSU Master's Theses

Given text which is a union of d documents of strings, D = d1, d2,...., dd, the emphasis of this thesis is to provide a practical framework to retrieve the K most relevant documents for a given pattern P, which comes as a query. This cannot be done directly, as going through every occurrence of the query pattern may prove to be expensive if the number of documents that the pattern occurs in is much more than the number of documents (K) that we require. Some advanced query functionality will be required, as compared to listing the documents that the …


Multi-Scale Habitat Associations Of Shorebirds During Spring Migration In Southwestern Louisiana Rice Fields, Rachel K. Villani Jan 2010

Multi-Scale Habitat Associations Of Shorebirds During Spring Migration In Southwestern Louisiana Rice Fields, Rachel K. Villani

LSU Master's Theses

Rice is the most common wetland crop in the world, and important for waterbirds and shorebirds worldwide, including the United States. In Louisiana, shorebirds use rice fields during spring migration, and are an important for foraging and refueling during migration. However, competing land uses and restoration projects may reduce the availability of rice fields, and impact the landscape that shorebirds use during migration. To determine how shorebirds use the landscape, I evaluated local and landscape factors affecting shorebird use of rice fields during spring migration in southwestern Louisiana. Using five habitat suitability zones (HSZs) based on rice density and canopy …


Choosing Between Remote I/O Versus Staging In Distributed Environments, Ibrahim Hakki Suslu Jan 2010

Choosing Between Remote I/O Versus Staging In Distributed Environments, Ibrahim Hakki Suslu

LSU Doctoral Dissertations

Today, scientifi_x000C_c applications and experiments have become increasingly complex and more demanding in terms of their computational and data requirements. The amount of data generated and used has grown at a very rapid rate. As tens or hundreds of terabytes of data for a single application is very common today; petabytes and even exabytes of data will be very common in a few years. One of the major challenges in distributed computing environments is how to access these large datasets remotely over the network. Data staging and remote I/O are the most widely used data access methods for distributed applications. …


Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron Jan 2010

Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron

LSU Doctoral Dissertations

Population growth for mallards (Anas platyrhynchos), and presumably other upland nesting ducks, in the Prairie Pothole Region is most sensitive to nest success, and nest success is most strongly influenced by predation. I evaluated the efficacy of reducing predator populations to improve nest success and increase local breeding populations of upland nesting ducks on township-sized (93.2 km2) management units in eastern North Dakota, USA, during 2005−2008. I also examined potential territorial limitations on local population growth for mallards. Trappers annually removed an average of 245 predators per trapped site. I monitored 7,489 nests on 7 trapped and 5 nontrapped sites, …


The Effects Of Self-Assessment On Student Learning Of Mathematics, Daniel James Hotard Jan 2010

The Effects Of Self-Assessment On Student Learning Of Mathematics, Daniel James Hotard

LSU Master's Theses

Self-assessment can be defined as students judging their own work, based on evidence and explicit criteria, for the purpose of improving future performance. Many researchers agree that implementation of student self-assessment in the classroom is an important tool for improving academic performance and self-efficacy. In this thesis, I investigated the effects of student self-assessment on learning gains of 81 alternative high school Algebra I students. This study took place over the course of two units of instruction. Classes were divided into two groups. One group of students utilized rubrics to self-assess their own work for the first unit, while the …


Metamorphic Rocks In The Sawtooth Mountains, Idaho, Usa: A Window Into The Precambrian Basement Of Southwest Laurentia, Kyle Michael Metz Jan 2010

Metamorphic Rocks In The Sawtooth Mountains, Idaho, Usa: A Window Into The Precambrian Basement Of Southwest Laurentia, Kyle Michael Metz

LSU Master's Theses

The western North American craton consists of a mosaic of Precambrian basement terranes that developed through episodes of microcontinent collision and magmatic arc accretion. Defining the extent and boundaries of these terranes is critical to deciphering the Precambrian development of Laurentia. The poorly exposed Selway terrane occurs between the Archean Wyoming province and the Neoproterozoic rifted margin of Laurentia. A rare exposure of Precambrian metamorphic rocks, the Sawtooth Metamorphic Complex (SMC), crops out over 33 km2 in the Sawtooth Mountains of Idaho, USA, and potentially provides a window into the deep crust of the region. Field mapping, petrographic analyses, and …


A Characterization Of Near Outer-Planar Graphs, Tanya Allen Lueder Jan 2010

A Characterization Of Near Outer-Planar Graphs, Tanya Allen Lueder

LSU Master's Theses

This thesis focuses on graphs containing an edge whose removal results in an outer-planar graph. We present partial results towards the larger goal of describing the class of all such graphs in terms of a finite list of excluded graphs. Specifically, we give a complete description of those members of this list that are not 2-connected or do not contain a subdivision of a three-spoke wheel. We also show that no members of the list contain a five-spoke wheel.


Effects Of Habitat Structural Complexity On Nekton Assemblages: Lab And Field Observations In Southern Louisiana, Austin T. Humphries Jan 2010

Effects Of Habitat Structural Complexity On Nekton Assemblages: Lab And Field Observations In Southern Louisiana, Austin T. Humphries

LSU Master's Theses

Greater structural complexity is often associated with more diverse and abundant species assemblages. Biogenic reefs formed by the eastern oyster (Crassostrea virginica) are structurally complex in nature and have been recognized for their potential habitat value in estuarine systems along the Atlantic and Gulf of Mexico coasts. To determine how the structural complexity of newly created oyster reefs may influence the abundance and distribution of species, three objectives were established. First, to examine spatial and temporal patterns of nekton use at newly created oyster reefs, as well as the impact of wave exposure, six paired oyster reef and mud-bottom treatments …


Introgression, Health, And Condition Of Florida, Northern, And Fx Hybrid Largemouth Bass In Louisiana Water Bodies, Melissa Ann Fries Jan 2010

Introgression, Health, And Condition Of Florida, Northern, And Fx Hybrid Largemouth Bass In Louisiana Water Bodies, Melissa Ann Fries

LSU Master's Theses

Since 1982, the Louisiana Department of Wildlife and Fisheries (LDWF) has stocked Florida-strain largemouth bass (FLMB; Micropterus salmoides floridanus) to incorporate Florida alleles into native populations (NLMB; M. s. salmoides) and enhance recreational fishing opportunities. I collected habitat data and largemouth bass samples from 12 LDWF stocked reservoirs and disconnected oxbow lakes to examine the relationships between reservoir characteristics, genetic identity, relative weight (Wr), liver somatic index (LSI), parasite loads, and back-calculated length-at-age. I examined the relationships between water body and genetic identity with Wr, LSI, and back-calculated length-at-age by ANOVA. Parasite loads were analyzed with ordinal regression. Principle component …


Positron Autoradiography For Intravascular Vulnerable Plaque Imaging, Peter Petrek Jan 2010

Positron Autoradiography For Intravascular Vulnerable Plaque Imaging, Peter Petrek

LSU Master's Theses

Purpose: To develop and investigate an intravascular storage phosphor detector for imaging and detection of vulnerable coronary artery plaques. Methods: The concept of the detection of vulnerable plaques (i.e., plaques with inflammation) is based on accumulation of fluorodeoxyglucose (FDG) in inflammation sites. The FDG is labeled with a radioactive isotope 18F (positron source), injected to patient, and accumulated in vulnerable plaques of coronary arteries. The radiation detector is then inserted into coronary artery, records positrons from FDG accumulated in vulnerable plaque, which allows for imaging and detection of the vulnerable plaque. A prototype detector was developed and tested. The detector …


Recent Advances In Glylons Science, Cornelia Rosu Jan 2010

Recent Advances In Glylons Science, Cornelia Rosu

LSU Master's Theses

A variety of sugar- based polyamides called glylons were synthesized by using different pathways. The sugar- units were derived from D- glucaric acid and D-galactaric acid. Glylons D-glucaric- based with pendant free hydroxyl groups showed a low solubility in organic solvents, due to hydroxyl preference to form strong intra- and intermolecular H- bonding. To minimize these interactions an acetalation reaction was performed. Monoacetalated D-glucaric-based po-lymers exhibited a better solubility in a broader range of solvents but the residual hydroxyl groups favored aggregation. Completely blocked bis-acetalated galactaric-based glylons are so-luble in a broad range of solvents including toluene/methanol mixtures. Deprotection reaction …