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Articles 3421 - 3450 of 3676
Full-Text Articles in Physical Sciences and Mathematics
Racks, Quandles And Virtual Knots, Victor Samuel Nelson
Racks, Quandles And Virtual Knots, Victor Samuel Nelson
LSU Doctoral Dissertations
We begin with a brief survey of the theory of virtual knots, which was announced in 1996 by Kauffman. This leads naturally to the subject of quandles and quandle homology, which we also briefly introduce. Chapter 2 contains a proof in terms of Gauss diagrams that the forbidden moves unknot virtual knots. This chapter includes material which has appeared in the Journal of Knot Theory and its Ramifications and is reprinted here by permission of World Scientific Publishing. In chapter 3 (cowritten with my advisor R.A.Litherland) we confirm a conjecture of J.S.Carter et.al. that the long exact sequence in rack …
Tidal Dynamics In The Bab El Mandab Strait, Ewa Jarosz
Tidal Dynamics In The Bab El Mandab Strait, Ewa Jarosz
LSU Doctoral Dissertations
The Bab el Mandab Strait is where the transition occurs between two noticeably different tidal regimes: the Gulf of Aden, where tidal fluctuations are mixed and have a range in excess of 2 m, and the Red Sea, where the tides are principally semidiurnal and their range is less than 1 m. Within the Strait, observations collected between May of 1995 and July of 1997 indicate that tidal currents are a mixed type and dominant constituents are the K1 and M2. The vertical structure of the tidal currents is complicated, differs between semidiurnal and diurnal constituents, and …
Mode Specific Photoionization Dynamics In Polyatomic Molecules, Gerald Jeffery Rathbone
Mode Specific Photoionization Dynamics In Polyatomic Molecules, Gerald Jeffery Rathbone
LSU Doctoral Dissertations
The work presented in this dissertation presents new work on polyatomic photoionization. In these investigations, the broad range behavior of both allowed and forbidden vibrational modes in linear triatomic systems were studied to understand mode specific aspects of photoionization. The current study is made possible by the experimental strategy of exploiting high resolution photoelectron spectroscopy and the high brightness of third generation synchrotron radiation sources. The data is taken typically tens of eV’s past the ionization potential. The strategy that I employ is to probe alternative vibrational modes which are frequently affected differently following resonant ionization. Such vibrationally resolved data …
Capillary And Microdevice Electrophoretic Tools For Genetic Analyses: Heteroduplex Analysis For Tuberculosis Drug Susceptibility And Ligase Detection Reaction For Colorectal Cancer Detection, Gloria Thomas
LSU Doctoral Dissertations
The traditional format of electrophoresis, the slab gel, is quickly being replaced by capillary and microdevice platforms, which offer improvements in cost, resolution, speed, quantitation and automation in genetic analyses. These techniques also employ a variety of separation matrices while the slab gel is limited to agarose and polyacrylamide. The research presented here explores the use of these electrophoretic formats for the detection of single nucleotide mutations using two genetic models associated with human disease. Slab gel based heteroduplex analysis (HDA), a popular mutation scanning method, uses a specially designed universal heteroduplex generator (UHG) containing controlled variation to enhance the …
Techniques To Explore Time-Related Correlation In Large Datasets, Sumeet Dua
Techniques To Explore Time-Related Correlation In Large Datasets, Sumeet Dua
LSU Doctoral Dissertations
The next generation of database management and computing systems will be significantly complex with data distributed both in functionality and operation. The complexity arises, at least in part, due to data types involved and types of information request rendered by the database user. Time sequence databases are generated in many practical applications. Detecting similar sequences and subsequences within these databases is an important research area and has generated lot of interest recently. Previous studies in this area have concentrated on calculating similitude between (sub)sequences of equal sizes. The question of unequal sized (sub)sequence comparison to report similitude has been an …
Predicting Electron Insert Output Factors At Nominal And Extended Source To Surface Distance, Ahmet Bulut
Predicting Electron Insert Output Factors At Nominal And Extended Source To Surface Distance, Ahmet Bulut
LSU Master's Theses
Two Varian linear accelerators were used to test the modified sector-integration method. This method can predict the electron insert factor for arbitrary inserts at different source to surface distances (SSD). The effective source distances (SSDeff) and insert factors (IF) for several accelerators are compared. The relationship of IF and SSDeff for machine type, energy, cone size, insert size and SSD is presented. The results were fed into the electron output determination module of an existing monitor unit calculator (MUCalc) which uses the modified sector integration method. Prediction and measurements were compared for various clinical inserts at several …
Of Manatees, Mangroves, And The Mississippi River: Is There An Estuarine Signature For The Gulf Of Mexico?, R. Eugene Turner
Of Manatees, Mangroves, And The Mississippi River: Is There An Estuarine Signature For The Gulf Of Mexico?, R. Eugene Turner
Faculty Publications
Important parameters of estuarine variability include morphology, flushing times, nutrient loading rates, and wetland: water ratios. This variability both reflects and disguises underlying relationships between the physics and biology of estuaries, which this comparative analysis seeks to reveal, using the Gulf of Mexico (GOM) estuaries as a starting point. A question used to focus this analysis is: are the GOM estuaries unique? The GOM receives the Mississippi River, a uniquely large, world-class river, which dominates the freshwater and nutrient inflows to the GOM continental shelf, whose margins include 35 major estuarine systems. These GOM estuaries have 28% and 41% of …
A Study On The Effect Of Storage Time On Specific Gravity And Eggshell Quality, Brock Kendall Laborde
A Study On The Effect Of Storage Time On Specific Gravity And Eggshell Quality, Brock Kendall Laborde
Honors Capstones
No abstract provided.
Constructing Regular Ramanujan Graphs Via Graph Extension, Sage Michelle Accardo
Constructing Regular Ramanujan Graphs Via Graph Extension, Sage Michelle Accardo
Honors Capstones
No abstract provided.
Synthesis And Analysis Of Three-Dimensional Molecular Architectures, Patricia Beck
Synthesis And Analysis Of Three-Dimensional Molecular Architectures, Patricia Beck
LSU Master's Theses
The use of resorcinarenes in the study of biologically significant phenomena has been the focus of much attention, due to the versatility of these macrocyclic compounds. In this thesis, two applications of resorcinarenes are explored. First, the search for the mechanism by which tetraarylboronic acid resorcinarenes lead to colorimetric detection and quantization of saccharide analyte concentration in solution is described. Second, the extension of the lower rim conjugation of the resorcinarene macrocycle by the fourfold addition of various length oligo(p-phenylene) rods is discussed. The synthesis of these tubular materials, with potential uses as artificial ion channels and for binding and …
Bounding The Wild Set (Counting The Minimum Number Of Wild Primes In Hilbert Symbol Equivalent Number Fields), Marius M. Somodi
Bounding The Wild Set (Counting The Minimum Number Of Wild Primes In Hilbert Symbol Equivalent Number Fields), Marius M. Somodi
LSU Doctoral Dissertations
This dissertation makes a contribution to the study of Witt rings of quadratic forms over number fields. To every pair of algebraic number fields with isomorphic Witt rings one can associate a number, called the minimum number of wild primes. The situation is particularly nice when this number is 0; often it is not 0. Earlier investigations have established lower bounds for this number. In this dissertation an analysis is presented that expresses the minimum number of wild primes in terms of the number of wild dyadic primes. This formula not only gives immediate upper bounds, but can be considered …
Artin-Schreier Families And 2-D Cycle Codes, Cem Guneri
Artin-Schreier Families And 2-D Cycle Codes, Cem Guneri
LSU Doctoral Dissertations
We start with the study of certain Artin-Schreier families. Using coding theory techniques, we determine a necessary and sufficient condition for such families to have a nontrivial curve with the maximum possible number of rational points over the finite field in consideration. This result produces several nice corollaries, including the existence of certain maximal curves; i.e., curves meeting the Hasse-Weil bound.We then present a way to represent two-dimensional (2-D) cyclic codes as trace codes starting from a basic zero set of its dual code. This representation enables us to relate the weight of a codeword to the number of rational …
Numerical Simulations Of Dynamical Mass Transfer In Binaries, Patrick Michael Motl
Numerical Simulations Of Dynamical Mass Transfer In Binaries, Patrick Michael Motl
LSU Doctoral Dissertations
We present results from investigations of mass transfer instability in close binary star systems. By unstable mass transfer we mean the exchange of material where the response of the binary to the initial Roche lobe overflow causes the donor to loose even more material. Our work is guided by approximate arguments that dictate the stability boundaries for binary star systems. To proceed further one must explicitly treat extended mass and velocity distributions that are both nitially, and through their subsequent evolution in time, self-consistent. In this dissertation, we present the first three-dimensional, fully self-consistent treatment of mass transfer in close …
Evaluation Of In Situ Bioremediation Approaches In Meeting International Standards For Organic And Residual Metals Toxicity In Soils, Jason Allan Mcdonald
Evaluation Of In Situ Bioremediation Approaches In Meeting International Standards For Organic And Residual Metals Toxicity In Soils, Jason Allan Mcdonald
LSU Master's Theses
Drilling fluids and muds are an essential component of the rotary drilling process used to drill for oil and gas on land and in offshore environments. However, the bioaccumulation of petroleum contaminated soils/drilling mud due to oil and natural gas exploration has posed a major environmental concern due to its prolonged environmental persistence and its leachability below the rhizosphere. The main objectives of this research were: (i) To assess initial toxicity of drilling mud and related contaminated soils from an agricultural setting in Galliano, Sicily (Phase one) and (ii) To develop a low intervention bioremediation approach using bioplug technology to …
The Synthesis Of Deuterated Arylamine Dna Adducts For Use In The Development Of An Isotope Dilution Lc/Ms/Ms Method, Philip Dmitri Olsen
The Synthesis Of Deuterated Arylamine Dna Adducts For Use In The Development Of An Isotope Dilution Lc/Ms/Ms Method, Philip Dmitri Olsen
LSU Doctoral Dissertations
Polycyclic aromatic amines (arylamines) are a class of chemical carcinogens that are prevalent in environmental and industrial settings. In order to study the mechanism of their toxicity a quantitative and qualitative detection method was developed to measure the C8-adenine adducts of benzidine and 2-aminofluorene in DNA samples. To do this a novel synthetic method using a palladium catalyst was developed to prepare authentic and deuterated arylamine adducts to serve as standards. These standards were then used to develop a high performance liquid chromatography, electrospray, tandem mass spectrometry, isotope dilution, detection method. To demonstrate the validity of this method two spike …
Analysis Of Inorganic Materials Using Advanced Nmr And Nqr Techniques, Anthony Adrian Mrse
Analysis Of Inorganic Materials Using Advanced Nmr And Nqr Techniques, Anthony Adrian Mrse
LSU Doctoral Dissertations
Several advanced solid-state nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) techniques have been applied to inorganic materials of commercial interest. The specific techniques applied to each system were chosen to solve specific obstacles which impeded the flow of industrial science.
First, the dispersion of brominated flame retardants in polymers is monitored using pulsed 81Br NQR (nuclear quadrupole resonance) techniques. The NQR spectrometer consists of a homemade NMR console and an automatically tuned loop-gap resonator probe. The two factors which affect the 81Br NQR transition frequencies of brominated aromatics are: electron-donating and withdrawing substituents on the ring …
Analysis Of Near-Infrared Dye-Labeled Sanger Sequencing Fragments With Gel Electrophoresis Using The Time-Resolved Flourescence Lifetime Indentification Methods, Suzanne Jeanel Lassiter
Analysis Of Near-Infrared Dye-Labeled Sanger Sequencing Fragments With Gel Electrophoresis Using The Time-Resolved Flourescence Lifetime Indentification Methods, Suzanne Jeanel Lassiter
LSU Doctoral Dissertations
The research presented in this dissertation involves the identification of sequencing fragments with time-resolved methods. For this application, near-infrared heavy-atom tricarbocyanine dyes were developed in our laboratory, which can be excited with a single laser and emission collected using a single detection channel. The dyes have four spectroscopically unique, but relatively short lifetimes that can be altered by the intramolecular heavy-atom they contain. The work described here involves the optimization of dye-primer chemistry for preparing Sanger sequencing reactions for longer reads and the optimization of the separation matrix for capillary gel electrophoresis that produces favorable statistical analysis of the aforementioned …
Iron Acquisition Systems And The Effect Of Iron On Virulence, Amy E. Noles
Iron Acquisition Systems And The Effect Of Iron On Virulence, Amy E. Noles
Honors Capstones
No abstract provided.
Salinity History Of Coastal Marshes Reconstructed From Diatom Remains, Michael L. Parsons, Quay Dortch, R. Eugene Turner, Nancy N. Rabalais
Salinity History Of Coastal Marshes Reconstructed From Diatom Remains, Michael L. Parsons, Quay Dortch, R. Eugene Turner, Nancy N. Rabalais
Faculty Publications
Sediment cores were collected from three Louisiana coastal marsh ponds, dated with radioisotopes, and analyzed for diatom remains to determine if long-term salinity changes were evident in the sediment record. A diatom-based salinity index formulated from a statistical comparison of available salinity data and changing diatom assemblages demonstrated that diatom remains appear to preserve salinity signals in coastal brackish and salt marsh environments. The salinity index was applied to sediment cores spanning the late 1600s to the 1990s and provided a more complete record of salinity than field data, which were temporally and spatially incomplete. The salinity reconstructions indicated that …
The Impact Of Accelerating Land-Use Change On The N-Cycle Of Tropical Aquatic Ecosystems: Current Conditions And Projected Changes, J. A. Downing, M. Mcclain, R. Twilley, J. M. Melack, J. Elser, Nancy N. Rabalais, W. M. Lewis Jr., R. Eugene Turner, J. Corredor, D. Soto, A. Yanez Arancibia, J. A. Kopaska, R. W. Howarth
The Impact Of Accelerating Land-Use Change On The N-Cycle Of Tropical Aquatic Ecosystems: Current Conditions And Projected Changes, J. A. Downing, M. Mcclain, R. Twilley, J. M. Melack, J. Elser, Nancy N. Rabalais, W. M. Lewis Jr., R. Eugene Turner, J. Corredor, D. Soto, A. Yanez Arancibia, J. A. Kopaska, R. W. Howarth
Faculty Publications
Published data and analyses from temperate and tropical aquatic systems are used to summarize knowledge about the potential impact of land-use alteration on the nitrogen biogeochemistry of tropical aquatic ecosystems, identify important patterns and recommend key needs for research. The tropical N-cycle is traced from pre-disturbance conditions through the phases of disturbance, highlighting major differences between tropical and temperate systems that might influence development strategies in the tropics. Analyses suggest that tropical freshwaters are more frequently N-limited than temperate zones, while tropical marine systems may show more frequent P limitation. These analyses indicate that disturbances to pristine tropical lands will …
Characterization Of Hypoxia: Topic 1 Report For The Integrated Assessment On Hypoxia In The Gulf Of Mexico, Nancy N. Rabalais, R. Eugene Turner, Dubravko Justic, Quay Dortch, William J. Wiseman
Characterization Of Hypoxia: Topic 1 Report For The Integrated Assessment On Hypoxia In The Gulf Of Mexico, Nancy N. Rabalais, R. Eugene Turner, Dubravko Justic, Quay Dortch, William J. Wiseman
Faculty Publications
No abstract provided.
Nutrient Enhanced Coastal Ocean Productivity In The Northern Gulf Of Mexico, William J. Wiseman Jr., Michael J. Dagg, Nancy N. Rabalais, Terry E. Whitledge
Nutrient Enhanced Coastal Ocean Productivity In The Northern Gulf Of Mexico, William J. Wiseman Jr., Michael J. Dagg, Nancy N. Rabalais, Terry E. Whitledge
Faculty Publications
No abstract provided.
Synthesis Of A Novel ??-Amino Acid Capable Of Stabilizing A 310-Helix Via Side-Chain Salt-Bridging, Reema K. Thalji
Synthesis Of A Novel ??-Amino Acid Capable Of Stabilizing A 310-Helix Via Side-Chain Salt-Bridging, Reema K. Thalji
Honors Capstones
No abstract provided.
Pressure Dependence Of The Metal-Insulator Transition In Fesi1-Xa1x, Brian Perone
Pressure Dependence Of The Metal-Insulator Transition In Fesi1-Xa1x, Brian Perone
Honors Capstones
No abstract provided.
Novel Precursors For Chemical Vapor Deposition Of Copper Metal, Zuzanna T. Cygan
Novel Precursors For Chemical Vapor Deposition Of Copper Metal, Zuzanna T. Cygan
Honors Capstones
No abstract provided.
The Two-Dimensional Ising Model: Mean-Field And Monte Carlo Results For Equilibrium And Nonequilibrium Transitions, Kevin Scott Brown
The Two-Dimensional Ising Model: Mean-Field And Monte Carlo Results For Equilibrium And Nonequilibrium Transitions, Kevin Scott Brown
Honors Capstones
No abstract provided.
Exact Real Computational Arithmetic Via Infinite Composition Of Mobiüs Transformations As Presented By Dr. Peter John Potts, Et Al., David Michael Robertson
Exact Real Computational Arithmetic Via Infinite Composition Of Mobiüs Transformations As Presented By Dr. Peter John Potts, Et Al., David Michael Robertson
Honors Capstones
No abstract provided.
Accounting For Sample Selection Bias In Louisiana Hmo Satisfaction Studies, Travis Warziniack
Accounting For Sample Selection Bias In Louisiana Hmo Satisfaction Studies, Travis Warziniack
Honors Capstones
No abstract provided.
Sand Body Geometry Of The Wax Lake Outlet Delta Atchafalaya Bay, Louisiana, Susan Majersky Fitzgerald
Sand Body Geometry Of The Wax Lake Outlet Delta Atchafalaya Bay, Louisiana, Susan Majersky Fitzgerald
LSU Historical Dissertations and Theses
Deltas forming in Atchafalaya Bay, L-ouisiana, are the result of delta switching by the Mississippi River. The larger Lower Atchafalaya River delta has been heavily manipulated by dredging for navigation, but the Wax Lake Outlet delta is largely undisturbed and an excellent example of a 'bayhead' delta. Combining stratigraphy, aerial photography and digital terrain model data sets, the developmental history of this delta is presented. The Wax Lake Outlet delta is comprised of a typical upward-coarsening sequence, although its prodelta unit is extremely limited. Its plan-view form is typical of deltas developing in low-energy, unstratified, shallow basins. Early developmental processes …
A Palynological Study Of Two Upland Bogs In The Gulf Coastal Plain, Alabama And Mississippi, Linda C. Pace
A Palynological Study Of Two Upland Bogs In The Gulf Coastal Plain, Alabama And Mississippi, Linda C. Pace
LSU Historical Dissertations and Theses
Fewer Quaternary palynological studies have been conducted in the Gulf Coastal Plain of the southeastern United States than In the northern United States and Canada, resulting in major gaps in the pollen record of this region. The existing studies display discrepancies in the chronology of the pine rise, appearance of the modem climatic regime and vegetation, and timing of the Hypsithermal. In order to fill a gap in the paleoecological data network of the Gulf Coastal Plain, pollen analysis, charcoal analysis, and sediment stratigraphic techniques were used to reconstruct the last 6500 years of Sweetbay Bog, Mississippi, and Minamac Bog, …