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Delineation Of A Produced Water Plume In Pointe Coupee Parish, Louisiana, Matthew C. Smith 2010 Louisiana State University and Agricultural and Mechanical College

Delineation Of A Produced Water Plume In Pointe Coupee Parish, Louisiana, Matthew C. Smith

LSU Master's Theses

Three pits were excavated in the 1960’s at the Fordoche Oil Field in Lottie, Louisiana, as evaporation pits for oil well produced brines. The pits were closed and completed in the 1980’s. Previous studies indicate that produced water has leached into the subsurface within the area to the south and southeast of the pits. Ground penetrating radar (GPR) was utilized in an attempt to delineate the present location of the plume as well as test the feasibility of GPR within a clayey soil in south Louisiana. In addition to collection of GPR data, electrical conductivity logs and soil ...


Status Of Wintering Grassland Birds In A Post-Hurricane, Salvage-Logged Forest, Matthew Edward Brooks 2010 Louisiana State University and Agricultural and Mechanical College

Status Of Wintering Grassland Birds In A Post-Hurricane, Salvage-Logged Forest, Matthew Edward Brooks

LSU Master's Theses

North American grassland birds have been declining at an alarming rate. Winter habitat for grassland species in the southeastern U.S. generally occurs within forests subject to management. I studied wintering grassland bird communities in De Soto National Forest in southern Mississippi. My objectives were to: 1) Assess bird communities and vegetation structure in upland forest stands that were salvage-logged following Hurricane Katrina, in stands managed for Red-cockaded Woodpeckers (Picoides borealis, RCW), and in stands containing bogs; and 2) Determine the extent of the association between vegetation and occurrence of the common wintering grassland birds. I conducted bird and vegetation ...


Evaluation Of The Effectiveness Of Cooperative Learning Structures In Improving Students' Performance, Jonah Njenga 2010 Louisiana State University and Agricultural and Mechanical College

Evaluation Of The Effectiveness Of Cooperative Learning Structures In Improving Students' Performance, Jonah Njenga

LSU Master's Theses

In a desperate attempt to improve high school classroom performances, recently, schools have begun to move towards incorporating cooperative learning strategies into their classrooms. Generally, cooperative learning strategies can be described as the use of small groups to encourage learners work together and accomplish shared goals and subsequently maximize theirs and others’ potential. In an attempt to evaluate the effectiveness of this strategy on classroom learning, this study compares the gains in means of scores between a group taught using cooperative learning strategies and another group taught using non-cooperative learning strategies. Fifty-three students taking Algebra I were given a pretest ...


Quantifying The Impact Of Data Quality On Searches For Gravitational Waves From Binary Coalescing Systems With Ligo, Jacob Peter Slutsky 2010 Louisiana State University and Agricultural and Mechanical College

Quantifying The Impact Of Data Quality On Searches For Gravitational Waves From Binary Coalescing Systems With Ligo, Jacob Peter Slutsky

LSU Doctoral Dissertations

Gravitational waves are ripples in space-time itself, predicted by Einstein's General theory of relativity, which propagate at the speed of light and are not scattered or extinguished by passing through matter almost at all. In particular, the gravitational waves from the coalescences of binary systems of compact objects, such as neutron stars and black holes, are exciting prospects for observation. The Laser Interferometer Gravitational-wave Observatory experiment intends to make the _x000C_first direct measurement of gravitational waves, and use the results to uncover new astrophysics. These observations will not be limited by extinction from dust and gas, and will probe ...


Modeling The Impacts Of Pulsed Riverine Inflows On Hydrodynamics And Water Quality In The Barataria Bay Estuary, Anindita Das 2010 Louisiana State University and Agricultural and Mechanical College

Modeling The Impacts Of Pulsed Riverine Inflows On Hydrodynamics And Water Quality In The Barataria Bay Estuary, Anindita Das

LSU Doctoral Dissertations

Eutrophication and coastal wetland loss are the major environmental problems affecting estuaries around the world. In Louisiana, controlled diversions of the Mississippi River water back into coastal wetlands are thought to be an important engineering solution that could reverse coastal land loss. There are concerns, however, that freshwater diversions may increase nutrient inputs and create severe eutrophication problems in estuaries and wetlands adjacent to the diversion sites. My dissertation research concerns modeling the effects of the observed and hypothetical freshwater diversion discharges on the hydrodynamics, salinity and water quality in the Barataria estuary, a deltaic estuary in south Louisiana. This ...


Developing Tools To Identify Factors That Limit Production In Coastal Marshes, Vanessa Danielle Tobias 2010 Louisiana State University and Agricultural and Mechanical College

Developing Tools To Identify Factors That Limit Production In Coastal Marshes, Vanessa Danielle Tobias

LSU Doctoral Dissertations

Marsh loss is a problem in many areas around the world. In Louisiana’s coastal marshes, where Spartina patens is the most common plant, restoration and management seek to slow wetland loss rates that average approximately 77.4 km2/year. To combat the problem, scientists and managers require tools to determine local causes and evaluate the effectiveness of management techniques. Current methods for identifying factors that limit productivity in marshes are too time-consuming or expensive for wide-spread, regular use. Critical values of elemental concentrations in plant tissue are widely used to diagnose mineral deficiencies and toxicities in agricultural crops, however ...


Early Life History Dynamics Of The Fish Community In The Atchafalaya River Basin, B. Thorpe Halloran 2010 Louisiana State University and Agricultural and Mechanical College

Early Life History Dynamics Of The Fish Community In The Atchafalaya River Basin, B. Thorpe Halloran

LSU Doctoral Dissertations

Seasonal overbank flooding in systems like the Atchafalaya River Basin (ARB) provides the opportunity for fishes in the mainstem to access off-channel areas on the floodplain. Typically, newly inundated floodplain habitats allow adult fishes to add biomass, avoid predation, and potentially, to reproduce. However, in systems like the ARB, the timing, duration, and magnitude of flooding infrequently coincides with known reproductive periods of many fishes assumed to be floodplain-dependent. To quantify the level of floodplain-exploitative fish reproduction in the ARB, I collected larval and juvenile fish with a variety of sampling gear that allowed estimates in both ultra-shallow (< 2-m) and continuously-inundated habitats (headwater lakes, canals, and bayous). A suite of water quality parameters, river stage, flow, and hours of daylight were used to gauge the influence of environmental phenomena on age-0 abundance during both inundation and drawdown. The results of the 19-month study suggest that many taxa do not rely on the floodplain to ensure high survivorship. Interestingly, the reproductive ecologies of many ARB fishes appeared to be largely independent of widespread connectivity. Although an increasing hydrograph appeared to enhance reproductive output, the interannual timing and intensity of spawning showed limited variability. Larval densities were also contrasted with the microcrustacean zooplankton (copepods and cladocerans) population to assess if a potential food limitation existed in the weeks and months following hatching. During the study, increased zooplankter abundance was typically preceded by elevated river-floodplain connectivity. Conversely, as floodwaters receded during the summer, zooplankton abundance declined to lowest levels observed during the study. Overall, there was limited synchronous overlap between the hatchlings of most fish taxa and their zooplankter prey. This could have potentially resulted in starvation and reduced annual recruitment. Yet, my analysis of the factors that regulate larval fish abundance in the ARB suggest that the density of zooplankton was highly significant although high numbers of larvae and zooplankton rarely coincided. Finally, I compared the intraday (morning vs. afternoon) density and mean length of larval fish at fixed sample sites. The results suggest that once-daily ichthyoplankton collections may fail to provide accurate density and length measurements for young fish populations.


Dimer Models For Knot Polynomials, Moshe Cohen 2010 Louisiana State University and Agricultural and Mechanical College

Dimer Models For Knot Polynomials, Moshe Cohen

LSU Doctoral Dissertations

A dimer model consists of all perfect matchings on a (bipartite) weighted signed graph, where the product of the signed weights of each perfect matching is summed to obtain an invariant. In this paper, the construction of such a graph from a knot diagram is given to obtain the Alexander polynomial. This is further extended to a more complicated graph to obtain the twisted Alexander polynomial, which involved "twisting" by a representation. The space of all representations of a given knot complement into the general linear group of a fixed size can be described by the same graph. This work ...


Investigating The Ironwood Tree (Casuarina Equisetifolia) Decline On Guam Using Applied Multinomial Modeling, Karl Anthony Schlub 2010 Louisiana State University and Agricultural and Mechanical College

Investigating The Ironwood Tree (Casuarina Equisetifolia) Decline On Guam Using Applied Multinomial Modeling, Karl Anthony Schlub

LSU Master's Theses

The ironwood tree (Casuarina equisetifolia), a protector of coastlines of the sub-tropical and tropical Western Pacific, is in decline on the island of Guam where aggressive data collection and efforts to mitigate the problem are underway. For each sampled tree the level of decline was measured on an ordinal scale consisting of five categories ranging from healthy to near dead. Several predictors were also measured including tree diameter, fire damage, typhoon damage, presence or absence of termites, presence or absence of basidiocarps, and various geographical or cultural factors. The five decline response levels can be viewed as categories of a ...


A Petrophysical Evaluation Of Factors That Control Cap Rock Seal Quality, Andrew Tyler Harrison 2010 Louisiana State University and Agricultural and Mechanical College

A Petrophysical Evaluation Of Factors That Control Cap Rock Seal Quality, Andrew Tyler Harrison

LSU Master's Theses

Textural and mineralogical variations within 33 shale samples were analyzed to provide a model for predication of hydrocarbon top-seal efficiency. Variation in mineral abundances in the subsurface influences petrophysical properties and other characteristics of hydrocarbon sealing sequences and reservoirs. In geophysical well logs, various proxies, such as gamma ray emission and neutron absorption, are used to assess changes in mineral composition. This study directly compares X-ray diffraction measurements of mineral percentages and geophysical responses from Middle Miocene cored intervals in the Santa Cruz Well; Mississippi Canyon block 519, Gulf of Mexico with those derived from well logging. Distinct textural differences ...


Estuarine Phytoplankton Response To Annual And Manipulated River Inputs, Jessica Czubakowski 2010 Louisiana State University and Agricultural and Mechanical College

Estuarine Phytoplankton Response To Annual And Manipulated River Inputs, Jessica Czubakowski

LSU Master's Theses

River water entering estuaries affects the physical and chemical environment at irregular intervals creating a highly dynamic aquatic habitat. Phytoplankton are important primary producers in estuaries that respond quickly to their changing environment. Since 1991, Breton Sound estuary in southeast Louisiana has been directly influenced by Mississippi River water through the Caernarvon Freshwater Diversion structure. Over a 12 month period, the phytoplankton response was examined, in terms of biomass, abundance, community composition and potential phycotoxin production to seasonal changes in river input into the estuary. Within this 12 month period, a short pulse study was also carried out to examine ...


Primes Of The Form X² + Ny² In Function Fields, Piotr Maciak 2010 Louisiana State University and Agricultural and Mechanical College

Primes Of The Form X² + Ny² In Function Fields, Piotr Maciak

LSU Doctoral Dissertations

Let n be a square-free polynomial over F_q, where q is an odd prime power. In this work, we determine which irreducible polynomials p in F_q[x] can be represented in the form X^2+nY^2 with X, Y in F_q[x]. We restrict ourselves to the case where X^2+nY^2 is anisotropic at infinity. As in the classical case over Z, the representability of p by the quadratic form X^2+nY^2 is governed by conditions coming from class field theory. A necessary and almost sufficient condition is that the ideal generated by p splits ...


Ferromagnetism And Transport In Diluted Magnetic Semiconductors, Abdolmadjid Nili 2010 Louisiana State University and Agricultural and Mechanical College

Ferromagnetism And Transport In Diluted Magnetic Semiconductors, Abdolmadjid Nili

LSU Doctoral Dissertations

This dissertation focuses on the study of ferromagnetism in Dilute Magnetic Semiconductors. To study these strongly correlated electronic systems, two non- perturbative techniques are used: the Dynamical Mean Field Approximation (DMFA) and the Dynamical Cluster Approximation (DCA). The model used for Dilute Magnetic Semiconductors (DMS) incorporates the strong spin-orbit couplings of the carrier holes as found in most III-V semiconductors doped with manganese such as Ga1-xMnxAs. Calculated within the DMFA, the spin-orbit coupling effects give rise to various interesting physics, primarily the anisotropic behavior of the impurity band that affect the charge transport properties in the ...


Koszul Duality For Multigraded Algebras, Fareed Hawwa 2010 Louisiana State University and Agricultural and Mechanical College

Koszul Duality For Multigraded Algebras, Fareed Hawwa

LSU Doctoral Dissertations

Classical Koszul duality sets up an adjoint pair of functors establishing an equivalence of categories. The equivalence is between the bounded derived category of complexes of graded modules over a graded algebra and the bounded derived category of complexes of graded modules over the quadratic dual graded algebra. This duality can be extended in many ways. We consider here two extensions: first we wish to allow a multigraded algebra, meaning that the algebra can be graded by any abelian group (not just the integers). Second, we will allow filtered algebras. In fact we are considering filtered quadratic algebras with an ...


Quantum Light For Quantum Technologies, William Nicholas Plick 2010 Louisiana State University and Agricultural and Mechanical College

Quantum Light For Quantum Technologies, William Nicholas Plick

LSU Doctoral Dissertations

In this thesis we will theoretically investigate three potentially useful physical systems, after first developing the theoretical framework necessary for studying them. First, we will study the multiphoton absorption properties of maximally path entangled number (N00N) states. This is directly relevant to quantum lithography, and beating the Rayleigh diffraction limit. Next, we will develop a new scheme for quantum interferometry: dubbed coherent-light boosted super-sensitive quantum interferometry, which has the potential to reach below the shot noise limit for high photon fluxes, and requires no esoteric detection protocol, or technological elements that have yet to be developed. Finally we propose a ...


Investigating The Effectiveness Of Informal Science Education Through Quantitative And Qualitative Analysis: Ocean Commotion, Catherine Angela Sutera 2010 Louisiana State University and Agricultural and Mechanical College

Investigating The Effectiveness Of Informal Science Education Through Quantitative And Qualitative Analysis: Ocean Commotion, Catherine Angela Sutera

LSU Master's Theses

Informal science education serves as an important source for science education for both individuals and school groups. However, the effectiveness of school visits to informal science education events outside of either museums or science centers has received little investigation. This study explores the short-term effects of a hands-on learning experience on students’ attitude and content knowledge. Specifically, it investigates the impact of Ocean Commotion, a one-day event where exhibitors present information and hands-on demonstrations about marine environments and products, especially those important to Louisiana. Pre-tests were utilized to document students’ initial knowledge of and attitude toward wetlands and the ocean ...


Predicting First Year Seedling Survival From Quality Distributions Of Bareroot Seedlings And Microsites, Puskar Nath Khanal 2010 Louisiana State University and Agricultural and Mechanical College

Predicting First Year Seedling Survival From Quality Distributions Of Bareroot Seedlings And Microsites, Puskar Nath Khanal

LSU Master's Theses

Seeding survival has been a continuing problem since the start of the commercial pine plantation in 1950s. The first-year survival of bare-root loblolly pine seedlings at intensively prepared sites in Louisiana has reached a survival plateau of 75 to 85 % with an average of almost 80 %. The major hypothesis of this research was that the survival plateau is a function of the interaction between the frequency distribution of seedling quality and the frequency distribution of microsite quality. This study examined bare-root seedlings and microsite variation, and analyzed the possible options to increase the first-year seedling survival. The study was approached ...


Multigrid Methods For Maxwell's Equations, Jintao Cui 2010 Louisiana State University and Agricultural and Mechanical College

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 ...


New Strategies For Phase Estimation In Quantum Optics, Yang Gao 2010 Louisiana State University and Agricultural and Mechanical College

New Strategies For Phase Estimation In Quantum Optics, Yang Gao

LSU Doctoral Dissertations

One important problem in quantum optics is to resolve an extremely small change of phase shift. The complementarity between photon number and phase sets an ultimate limit, the so-called Heisenberg limit, on the phase measurement sensitivity. The precise phase estimation has many technological applications, such as optical gyroscopes, gravitational wave detection, quantum imaging and sensing. In this thesis I show that the utilization of the parity measurement in the optical interferometry is actually applicable to a wide range of quantum entangled input states. Comparison of the performance of the various quantum states then can be made within such a unified ...


Studies Of Nanoparticles From A Group Of Uniform Materials Based On Organic Salts (Gumbos), Aaron Tesfai 2010 Louisiana State University and Agricultural and Mechanical College

Studies Of Nanoparticles From A Group Of Uniform Materials Based On Organic Salts (Gumbos), Aaron Tesfai

LSU Doctoral Dissertations

Tesfai, Aaron, B.S., B.A., University of Missouri, Columbia, 2003 Doctor of Philosophy, Spring Commencement 2010 Major: Chemistry Studies of Nanoparticles from a Group of Uniform Materials Based on Organic Salts (GUMBOS) Dissertation directed by Professor Isiah M. Warner Pages in dissertation, 101. Words in abstract, 271. Ionic liquids (ILs) are defined as organic salts composed of ions with melting points at or below 100 °C. ILs have gained considerable attention because of their desirable properties such as low volatility, high thermal stability, and tunability. GUMBOS are an emergent class of organic salts, many of which are ionic liquids ...


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