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Design And Development Of Chiral And Achiral Molecularly Imprinted Stationary Phases, Jason Paul LeJeune 2010 Louisiana State University and Agricultural and Mechanical College

Design And Development Of Chiral And Achiral Molecularly Imprinted Stationary Phases, Jason Paul Lejeune

LSU Doctoral Dissertations

Although the cross-linker can comprise over 80% of the polymer composition, improving the nature of the cross-linker in molecularly imprinted polymers has not been studied extensively. The goal of this research is to develop novel cross-linking monomers to either use in the One MoNomer Molecularly Imprinted Polymer system (OMNiMIP) or use in conjunction with other commercially available cross-linkers and functional monomers. Chapter 2 contains research into the understanding of the performance of a new cross-linking monomer (N, O - bismethacryloyl ethanolamine, NOBE) discovered in the Spivak Research Group. The ability of this monomer to outperform traditional two monomer systems in a ...


Homogenization Of Nonlinear Partial Differential Equations, Silvia Jiménez 2010 Louisiana State University and Agricultural and Mechanical College

Homogenization Of Nonlinear Partial Differential Equations, Silvia Jiménez

LSU Doctoral Dissertations

This dissertation is concerned with properties of local fields inside composites made from two materials with different power law behavior. This simple constitutive model is frequently used to describe several phenomena ranging from plasticity to optical nonlinearities in dielectric media. We provide the corrector theory for the strong approximation of fields inside composites made from two power law materials with different exponents. The correctors are used to develop bounds on the local singularity strength for gradient fields inside microstructured media. The bounds are multiscale in nature and can be used to measure the amplification of applied macroscopic fields by the ...


Age Related Productivity And Consistency Of Nest Initiation Timing Of Wild Mallards In Eastern North Dakota, Timothy Charles Kimmel 2010 Louisiana State University and Agricultural and Mechanical College

Age Related Productivity And Consistency Of Nest Initiation Timing Of Wild Mallards In Eastern North Dakota, Timothy Charles Kimmel

LSU Master's Theses

Mallards Anas platyrhnchos are arguably the most researched waterfowl species in North America. They exhibit great flexibility in certain breeding metrics such as timing of nest initiation and clutch size. A study on captive female Mallards (Batt and Prince 1979) fed ad libitum, held in identical breeding compartments, and paired with the same mate in each year of the study exhibited substantial variation in the timing of nest initiation within a given year, yet some individual females demonstrated consistency in initiation date among years. My objective was to examine breeding metrics such as timing of nest initiation and clutch size ...


Perverse Poisson Sheaves On The Nilpotent Cone, Jared Lee Culbertson 2010 Louisiana State University and Agricultural and Mechanical College

Perverse Poisson Sheaves On The Nilpotent Cone, Jared Lee Culbertson

LSU Doctoral Dissertations

For a reductive complex algebraic group, the associated nilpotent cone is the variety of nilpotent elements in the corresponding Lie algebra. Understanding the nilpotent cone is of central importance in representation theory. For example, the nilpotent cone plays a prominent role in classifying the representations of finite groups of Lie type. More recently, the nilpotent cone has been shown to have a close connection with the affine flag variety and this has been exploited in the Geometric Langlands Program. We make use of the following important fact. The nilpotent cone is invariant under the coadjoint action of G on the ...


Model Based Analysis Of Some High Speed Network Issues, Suman Kumar 2010 Louisiana State University and Agricultural and Mechanical College

Model Based Analysis Of Some High Speed Network Issues, Suman Kumar

LSU Doctoral Dissertations

The study of complex problems in science and engineering today typically involves large scale data, huge number of large-scale scientific breakthroughs critically depends on large multi-disciplinary and geographically-dispersed research teams, where the high speed network becomes the integral part. To serve the ongoing bandwidth requirement and scalability of these networks, there has been a continuous evolution of different TCPs for high speed networks. Testing these protocols on a real network would be expensive, time consuming and more over not easily available to the researchers worldwide. Network simulation is well accepted and widely used method for performance evaluation, it is well ...


Palynological Analysis Of Tiger And Trinity Shoals, Louisiana Continental Shelf, Russell Ryan Crouch 2010 Louisiana State University and Agricultural and Mechanical College

Palynological Analysis Of Tiger And Trinity Shoals, Louisiana Continental Shelf, Russell Ryan Crouch

LSU Master's Theses

Forty sediment samples taken from twenty-six vibracores collected from Holocene shoals (Tiger and Trinity) were processed for palynomorphs and analyzed to characterize the terrestrial and marine paleo-environments of southern Louisiana at the time of deposition of each shoal. Abundant and diverse pollen assemblages were recovered while marine microplankton were sparse (< 2% relative abundance). Pollen species were grouped by plants of similar environmental significances including arboreal, non-arboreal, aquatic, and shrub categories. Palynological signals were compared in detail between each core, as well as along strike and dip transects, to help determine whether or not these shoals were deposited coevally or in distinct depositional cycles. Evidence shows that Tiger and Trinity Shoals carry remarkably similar palynological profiles, indicating that sediments of these shoals areS from the same source, and that deposition extended over an interval of time such that climate change was not sufficient enough to alter the vegetation response (hence palynological signal). Pollen profiles show source sediments are predominantly from the lower Mississippi River drainage basin and exhibit species similar to those present in modern Louisiana coastal marshes and swamps (i.e., Taxodium distichum, Cyperaceae, Graminae, Chenopodiaceae, and Asteraceae), and coastal to upland hardwood forests of the Mississippi River alluvial valley (i.e., Pinus, Quercus, Carya, and Liquidambar styraciflua).


Bioaerosols And The Risk Of Upper Respiratory Infection In Dental Hygienists, Christen Rebecca Gautreau 2010 Louisiana State University and Agricultural and Mechanical College

Bioaerosols And The Risk Of Upper Respiratory Infection In Dental Hygienists, Christen Rebecca Gautreau

LSU Master's Theses

Multitudes of pathogenic and infectious microbes are known to spread via contaminated aerosols. Dental personnel have an increased incidence of respiratory infections. Ultrasonic scaling procedures are reported to produce the largest amounts of contaminated aerosols of any dental procedure. The goal of the current study was to see if dental hygienists are at an increased risk of respiratory infections during the performance of their job and to see if certain dental procedures had a significant effect on this risk. This study was conducted at the Dental Hygiene Clinic of the Louisiana State University School of Dentistry in New Orleans, LA ...


Non-Axisymmetric Instabilities In Self-Gravitating Tori Around Black Holes, And Solving Einstein Constraints With Superconvergent Finite Element Methods, Oleg Korobkin 2010 Louisiana State University and Agricultural and Mechanical College

Non-Axisymmetric Instabilities In Self-Gravitating Tori Around Black Holes, And Solving Einstein Constraints With Superconvergent Finite Element Methods, Oleg Korobkin

LSU Doctoral Dissertations

This thesis contains results on two related projects. In the first project, we explore non-axisymmetric instabilities in general relativistic accretion disks around black holes. Such disks are created as transient structures in several astrophysical scenarios, including mergers of compact objects and core collapse of massive stars. These disks are suggested for the role of cenral engines of gamma-ray bursts. We address the stability of these objects against the runaway and non-axisymmetric instabilities in the three-dimensional hydrodynamical fully general relativistic treatment. We explore three slender and moderately slender disk models with varying disk-to-black hole mass ratio. None of the models that ...


Calibrating And Improving The Sensitivity Of The Ligo Detectors, Jeffrey S. Kissel 2010 Louisiana State University and Agricultural and Mechanical College

Calibrating And Improving The Sensitivity Of The Ligo Detectors, Jeffrey S. Kissel

LSU Doctoral Dissertations

The Laser Interferometer Gravitational wave Observatory (LIGO) is network of three, power recycled Fabry-Perot Michelson interferometers built to detect gravitational waves from astrophysical sources at frequencies between 40 and 6000 Hz. For their fifth science run, from 2005 to 2007, the detectors observed at designed sensitivity, achieving equivalent strain amplitude noise of 3x10^−23 strain/rtHz at 100 Hz. To date, the observatory has not detected gravitational waves. However, even at such sensitivity, the expected detection rate for known astrophysical sources of gravitational waves is likely 0.02 yr^−1. The fundamental noise source of these ground-based detectors limiting the ...


Chemistry Of Rhenium(I) Tricarbonyl Complexes Of Biomedical Relevance, Theshini Perera 2010 Louisiana State University and Agricultural and Mechanical College

Chemistry Of Rhenium(I) Tricarbonyl Complexes Of Biomedical Relevance, Theshini Perera

LSU Doctoral Dissertations

fac-[ReI(CO)3L]n complexes serve as models for short-lived fac-[99mTcI(CO)3L] imaging tracers. Dangling groups on L, needed to achieve desirable biodistribution, complicate the NMR spectra, which are not readily understood. In fac-[ReI(CO)3L]+ with less complicated L, NH groups (exo-NH) projecting toward the L face sometimes showed an upfield shift attributable to steric shielding of the exo-NH group from the solvent by the chelate rings. To investigate whether exo-NH groups in six-membered rings exhibit the same effect and whether the presence of dangling ...


Improving Software Quality Using An Ontology-Based Approach, Yixin Luo 2010 Louisiana State University and Agricultural and Mechanical College

Improving Software Quality Using An Ontology-Based Approach, Yixin Luo

LSU Doctoral Dissertations

Ensuring quality in software development is a challenging process. The concepts of anti-pattern and bad code smells utilize the knowledge of reoccurring problems to improve the quality of current and future software development. Anti-patterns describe recurring bad design solutions while bad code smells describe source code that is error-free but difficult to understand and maintain. Code refactoring aims to remove bad code smells without changing a program’s functionality while improving program quality. There are metrics-based tools to detect a few bad code smells from source code; however, the knowledge and understanding of these indicators of low quality software are ...


Paleolimnological Reconstruction Of Hydrologic Change In The Slave River And Great Slave Lake During The Past Millennium, Matthew Ennis 2010 Wilfrid Laurier University

Paleolimnological Reconstruction Of Hydrologic Change In The Slave River And Great Slave Lake During The Past Millennium, Matthew Ennis

Theses and Dissertations (Comprehensive)

The Slave River Delta (SRD), NWT, represents a pivotal node in the upper Mackenzie Basin watershed and is a productive northern wetland landscape with a rich natural and cultural heritage. Concerns over environmental consequences of natural and anthropogenic-driven decline in river discharge as well as climate variability have prompted hydroecological sstudies to improve understanding of how this ecosystem functions over time and space. However, long-term natural hydrological variability of the Slave River system is not well documented and needs to be further developed. In order to provide a temperal context for understanding and evaluating the impacts of climate variability and ...


Synthesis Of Aza-Bridged Tetraphosphine Ligands For A Dirhodium Hydroformylation Catalyst, Scott Michael Boudreaux 2010 Louisiana State University and Agricultural and Mechanical College

Synthesis Of Aza-Bridged Tetraphosphine Ligands For A Dirhodium Hydroformylation Catalyst, Scott Michael Boudreaux

LSU Master's Theses

A novel tetraphosphine ligand rac-et,ph-P4 (et,ph-P4 = PEt2CH2CH2(Ph)PCH2P(Ph)CH2CH2PEt2) is used for the formation of a highly active and regioselective hydroformylation catalyst. The active catalytic species, Rh2H2(ƒÝ-CO)2(et,ph-P4)]2+, is formed in situ under H2/CO pressure. This is one of the most impressive examples of homobimetallic cooperativity in homogeneous catalysis. The fragmentation of this catalyst by CO has been investigated and confirmed by in situ NMR spectroscopic studies. A new tetraphosphine ligand rac-et,ph-P4-Ph (et,ph-P4-Ph = PEt2(o-C6H4)P(Ph)CH2(Ph)P(o-C6H4)PEt2) has been synthesized to combat this fragmentation ...


Littoral Cells, Longshore Transport And Wave Climate: An Examination Of Littoral Transport Along The Western Shore Of Prince Edward County, Ontario, Jayson A. Childs 2010 Wilfrid Laurier University

Littoral Cells, Longshore Transport And Wave Climate: An Examination Of Littoral Transport Along The Western Shore Of Prince Edward County, Ontario, Jayson A. Childs

Theses and Dissertations (Comprehensive)

This study discusses the wave climate and potential littoral transport along the western shore of Prince Edward County approximately two hours east of Toronto along the northern shoreline of Lake Ontario. The limestone headlands and barrier bars of the western coast are exposed toward a southwesterly fetch of approximately 200 km that can produce large offshore wave heights of 2–5 m. The wave model STWAVE was used to transform a standard set of wave conditions developed from recent hindcast data to examine fair weather, storm and extreme conditions for five directions between south and west-northwest along the shore. The ...


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 ...


Single Magnetic Molecule Between Conducting Leads: Effect Of Mechanical Rotations, Reem Jaafar, Eugene M. Chudnovsky, Dmitry A. Garanin 2010 CUNY Lehman College

Single Magnetic Molecule Between Conducting Leads: Effect Of Mechanical Rotations, Reem Jaafar, Eugene M. Chudnovsky, Dmitry A. Garanin

Publications and Research

We study spin-rotation effects in a magnetic molecule bridge d between two conducting leads. Dy- namics of the total angular momentum couples spin tunneling to the mechanical rotations. Landau- Zener spin transition produced by the time-dependent magne tic field generates a unique pattern of mechanical oscillations that can be detected by measuring t he electronic tunneling current through the molecule.


Dipolar Ordering In Crystals Of Mn12 Ac, Dmitry A. Garanin 2010 CUNY Lehman College

Dipolar Ordering In Crystals Of Mn12 Ac, Dmitry A. Garanin

Publications and Research

Ordering in realistic elongated box-shape crystals of the molecular magnet Mn_12 Ac is investigated with the site-resolved mean-field approximation that does not assume a uniform ordering. It is shown that ferromagnetic ordering should not occur in crystals with the aspect ratio up to 12. Instead, for the aspect ratio about 6, the inner and outer regions of the crystal order in different directions, uniformly along its length. Finding ordering temperature by extrapolating the inverse susceptibility curve does not provide a correct T_C.


On The Casimir Interaction Between Holes In A Plate, Daniel N. Kabat, Dimitra Karabali, V P. Nair 2010 CUNY Lehman College

On The Casimir Interaction Between Holes In A Plate, Daniel N. Kabat, Dimitra Karabali, V P. Nair

Publications and Research

We study the leading long-distance attractive force between two holes in a plate arising from a scalar eld with Dirichlet boundary conditions on the plate. We use a formalism in which the interaction is governed by a non-local eld theory which lives on the two holes. The interaction energy is proportional to Q1Q2=r7 at large separation r, where Q1 and Q2 are certain charges associated with the holes. We compute these charges for round and rectangular holes. We show that the 1=r7 behavior is universal for separations large compared to the linear dimensions of the holes, irrespective of ...


The Hamiltonian Approach To Yang-Mills (2 + 1): Expansion Scheme And Corrections To String Tension, Dimitra Karabali, V P. Nair, Alexandr Yelinkov 2010 CUNY Lehman College

The Hamiltonian Approach To Yang-Mills (2 + 1): Expansion Scheme And Corrections To String Tension, Dimitra Karabali, V P. Nair, Alexandr Yelinkov

Publications and Research

We carry out further analysis of the Hamiltonian approach to Yang-Mills theory in 2+1 dimensions which helps to place the calculation of the vacuum wave function and the string tension in the context of a systematic expansion scheme. The solution of the Schrodinger equation is carried out recursively. The computation of correlators is re-expressed in terms of a two-dimensional chiral boson theory. The effective action for this theory is calculated to first order in our expansion scheme and to the fourth order in a kinematic expansion parameter. The resulting corrections to the string tension are shown to be very ...


A Multivalent Dna Aptamer Specific For The B-Cell Receptor On Human Lymphoma And Leukemia, Prabodhika R. Mallikaratchy, Alessandro Ruggiero, Jeffrey R. Gardner, Vitaly Kuryavyi, William F. Maguire, Mark L. Heaney, Michael R. McDevitt, Dinshaw J. Patel, David A. Scheinberg 2010 CUNY Lehman College

A Multivalent Dna Aptamer Specific For The B-Cell Receptor On Human Lymphoma And Leukemia, Prabodhika R. Mallikaratchy, Alessandro Ruggiero, Jeffrey R. Gardner, Vitaly Kuryavyi, William F. Maguire, Mark L. Heaney, Michael R. Mcdevitt, Dinshaw J. Patel, David A. Scheinberg

Publications and Research

Long-term survival still eludes most patients with leukemia and non-Hodgkin’s lymphoma. No approved therapies target the hallmark of the B cell, its mIgM, also known as the B-cell receptor (BCR). Aptamers are small oligonucleotides that can specifically bind to a wide range of target molecules and offer some advantages over antibodies as therapeutic agents. Here, we report the rational engineering of aptamer TD05 into multimeric forms reactive with the BCR that may be useful in biomedical applications. Systematic truncation of TD05 coupled with modification with locked nucleic acids (LNA) increased conformational stability and nuclease resistance. Trimeric and tetrameric versions ...


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