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Articles 1081 - 1110 of 1402
Full-Text Articles in Physical Sciences and Mathematics
A Multi-Proxy Approach To Investigating The Latest Holocene (~4,500 Yrs. Bp) Vegetational History Of Catahoula Lake, Louisiana, Rebecca Ann Tedford
A Multi-Proxy Approach To Investigating The Latest Holocene (~4,500 Yrs. Bp) Vegetational History Of Catahoula Lake, Louisiana, Rebecca Ann Tedford
LSU Doctoral Dissertations
A multi-proxy investigation of sediments examined from Catahoula Lake, Louisiana has provided a record of late-Holocene vegetational changes, related to both hydrology and climate. This study integrates data from phytoliths, pollen, stable isotopes, magnetic susceptibility, and core sediment analysis. A modern phytolith analog assessed the phytoliths production in local plants and their modern soil sample distribution within the established lake vegetation zones. Fifty of the 76 species produced both distinctive and redundant phytoliths. The modern soil sample database indicates that phytoliths produced from both monocotyledon and dicotlyledon plant groups prove useful in distinguishing between forest and grassland communities and identifying …
Proxy Records Of Paleohurricanes For The Western And Southern Caribbean, Terrence Allen Mccloskey
Proxy Records Of Paleohurricanes For The Western And Southern Caribbean, Terrence Allen Mccloskey
LSU Doctoral Dissertations
This dissertation evaluates the hypothesis that hurricane activity levels in the North Atlantic during the late Holocene have been driven by latitudinal movements of the North Atlantic circulation system. Multi-millennial sedimentary proxy records, based on the occurrence of overwash clastic layers, provide clear evidence of abruptly alternating periods of hurricane landfall frequency for Nicaragua and Belize. Three Belizean transects exhibit an Active period (hyperactivity) occurring from ~2000-6000 cal yr BP, although dating is inconsistent across the transects. An Active period covering the last 500 years is found at one location. The Nicaraguan record, derived from three transects covering >90 km …
Peptide Targeting Of Platinum Anti-Cancer Drug And Synthesis Of Water Soluble Monofunctional Pt(Ii) Complexes Useful For Biological Labeling, Margaret W. Ndinguri
Peptide Targeting Of Platinum Anti-Cancer Drug And Synthesis Of Water Soluble Monofunctional Pt(Ii) Complexes Useful For Biological Labeling, Margaret W. Ndinguri
LSU Doctoral Dissertations
Platinum has been used as an inorganic medicinal agent with various applications such as anti cancer agents. Several new targeted Pt(II) conjugates were synthesized having the NGR and LHRH targeting motif. The platinum conjugates bearing the NGR motif revealed selective delivery and destruction of cancer cells that had CD13 receptors compared to untargeted carboplatin drug. The development of targeted chemotherapeutic has opened a new approach for efficient delivery of antitumor toxins with minimal exposure to normal cells. Several peptide sequences are known to have the ability to target tumors, for instance NGR motif which home specifically in solid tumors and …
The Segal-Bargmann Transform On Inductive Limits Of Compact Symmetric Spaces, Keng Wiboonton
The Segal-Bargmann Transform On Inductive Limits Of Compact Symmetric Spaces, Keng Wiboonton
LSU Doctoral Dissertations
We construct the Segal-Bargmann transform on the direct limit of the Hilbert spaces $\{L^2(M_n)^{K_n}\}_n$ where $\{M_n = U_n/K_n\}_n$ is a propagating sequence of symmetric spaces of compact type with the assumption that $U_n$ is simply connected for each $n$. This map is obtained by taking the direct limit of the Segal-Bargmann tranforms on $L^2(M_n)^{K_n}, \ n = 1,2,...$. For each $n$, let $\widehat{U_n}$ be the set of equivalence classes of irreducible unitary representations of $U_n$ and let $\widehat{U_n/K_n} \subseteq \widehat{U_n}$ be the set of $K_n$-spherical representations. The definition of the propagation gives a nice property allowing us to embed $\widehat{U_n/K_n}$ …
Utilization Of Aptamers As Affinity Probes In Polymeric Microdevices For Disease Management And The Production Of A Recombinant Membrane Protein, Anne Obubuafo
LSU Doctoral Dissertations
Aptamers have emerged as potential affinity agents that rival or complement antibodies in developing diagnostic assays for disease detection. We have demonstrated the use of PMMA microfluidic devices for conducting rapid affinity microchip CGE of a target protein using aptamers as the affinity probes with an electrophoresis development time of <2 min. Migration times were reproducible for thrombin complexes and free aptamers in CGE buffer with device-to-device RSD variations below 10%. By removing salts from plasma and adding an unlabeled random sequence oligonucleotide to the plasma, thrombin was detected in plasma. This method can be easily adapted to high-throughput parallel screening of plasma samples in multi-channel polymeric microdevices. The expression of rEpCAM in bacteria and mammalian cells was investigated with results showing successful expression in the mammalian systems, while protein expression in the bacteria was inhibited. Higher and prolonged expression levels were obtained in Cos 7 cells as compared to BHK and Hep2 cells due to episomal expression in Cos 7 cells. By combining a one-step IMAC procedure with electrophoresis and electro elution a more selective approach to obtaining electrophoretically pure rEpCAM was achieved. We developed dual-aptamer sandwich assays for thrombin and PDGF-BB targets on PMMA substrate using UV modification with a one-step EDC/NHS coupling reaction. Results indicate that the use of high EDC concentrations lead to faster immobilization and increased coverage density with a shorter sandwich assay development time. The assays were sensitive for both proteins and showed linearity in fluorescence response to changing protein concentration. Single molecule detection methods provide high sensitivity techniques in which aptamers can find use. We have demonstrated the use of two aptamers in a FRET-based assay for the detection of low levels of thrombin. Sensitivity and reliability of the aptamer smFRET assay depends on complex formation and stability. Due to the dissociation constants of the aptamers, single molecule events detected were below the calculated value for a 6 pM concentration of thrombin. Future work will involve adjusting the single molecule system by the use of pinholes to enable analysis of higher sample concentrations.
Space-Time Multiresolution Approach To Atomistic Visualization, Dipesh Bhattarai
Space-Time Multiresolution Approach To Atomistic Visualization, Dipesh Bhattarai
LSU Doctoral Dissertations
Time-varying three-dimensional positional atomistic data are rich in spatial and temporal information. The problem is to understand them. This work offers multiple approaches that enable such understanding. An interactive atomistic visualization system is developed integrating complex analyses with visualization to present the data on space-time multiresolution basis facilitating the information extraction and generate understanding. This work also shows the usefulness of such an integrated approach. The information obtained from the analyses represents the system at multiple length and time scales. Radial distribution function (RDF) provides a complete average spatial map of the distribution of the atoms in the system which …
Searching For Gravitational Waves From Binary Systems In Non-Stationary Data, Chad Hanna
Searching For Gravitational Waves From Binary Systems In Non-Stationary Data, Chad Hanna
LSU Doctoral Dissertations
The gravitational wave detectors at the LIGO Observatories have achieved record sensitivity to gravitational-waves produced by astrophysical systems. The LIGO Scientific Collaboration has analyzed data taken in several science runs, searching for different signals. We describe a search for black holes with less than a solar mass in the LIGO data taken from February 22 to March 24, 2005. No gravitational waves were found, and an upper limit was set on the rate of mergers of such binary systems. This search, as well as other searches for binary systems, are affected by non-stationary noise. We describe the sophisticated pipeline that …
Trace Forms Of Abelian Extensions Of Number Fields, Karli Smith
Trace Forms Of Abelian Extensions Of Number Fields, Karli Smith
LSU Doctoral Dissertations
This dissertation is concerned with providing a description of certain symmetric bilinear forms, called trace forms, associated with finite normal extensions N/K of an algebraic number field K, with abelian Galois group Gal(N/K). These abelian trace forms are described up to Witt equivalence, that is, they are described as elements in the Witt ring W(K). Complete descriptions are obtained when the base field K has exactly one dyadic prime and either no real embeddings or one real embedding. For these fields K, the set of abelian trace forms is closed under multiplication in the Witt ring W(K).
Multiscale Analysis Of Heterogeneous Media For Local And Nonlocal Continuum Theories, Bacim Alali
Multiscale Analysis Of Heterogeneous Media For Local And Nonlocal Continuum Theories, Bacim Alali
LSU Doctoral Dissertations
The dissertation provides new multiscale methods for the analysis of heterogeneous media. The first part of the dissertation treats heterogeneous media using the theory of linear elasticity. In this context, a methodology is presented for bounding the higher order moments of the local stress and strain fields inside random elastic media. Optimal lower bounds that are given in terms of the applied loading and the volume (area) fractions for random two-phase composites are presented. These bounds provide a means to measure load transfer across length scales relating the excursions of the local fields to applied loads. The second part of …
Laplace Transform Inversion And Time-Discretization Methods For Evolution Equations, Koray Ozer
Laplace Transform Inversion And Time-Discretization Methods For Evolution Equations, Koray Ozer
LSU Doctoral Dissertations
In this dissertation, we introduce Post-Widder-type inversion methods for the Laplace transform based on A-stable rational approximations of the exponential function. Since the results hold for Banach-space-valued functions, they yield efficient time-discretization methods for evolution equations of convolution type; e.g., linear first and higher order abstract Cauchy problems, inhomogeneous Cauchy problems, delay equations, Volterra and integro-differential equations, and problems that can be re-written as an abstract Cauchy problem on an appropriate state space.
Effect Of Hydrology On The Structure And Function Of Mangrove Ecosystems In The Can Gio Mangrove Biosphere Reserve, Vietnam, Loi Tan Le
LSU Doctoral Dissertations
The influence of hydrology on the mangrove forests of Vietnam has received little scientific attention, even though hydrology is recognized as the primary forcing function in mangrove ecosystems worldwide. The purpose of this dissertation research was to determine the effects of hydrology on specific structural attributes and functional processes within the mangrove forests of Can Gio, a province in southeastern Vietnam. Khe Vinh (KV) and Mui O (MO), two locations within compartment 17 of the Can Gio Mangrove Biosphere Reserve, were chosen as study sites. This research addressed two questions: (1) What are the characteristics of the hydrological regime at …
Off-Line Maldi Mass Spectrometry Of Bioaerosols, Jae-Kuk Kim
Off-Line Maldi Mass Spectrometry Of Bioaerosols, Jae-Kuk Kim
LSU Doctoral Dissertations
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used for off-line analysis of bioaerosols. The overall goal of the work is to develop methods and instrumentation to minimize sample treatment and maximize sensitivity and selectivity for bioaerosol analysis. This work is divided into three parts: sample preparation, test bioaerosol analysis, and instrument development. Untreated silicon wafer substrates were used as an alternate to conventional stainless steel targets and proved to be excellent substrates for large molecule analyses as well as small molecule analyses with excellent spot-to-spot and shot-to-shot reproducibility, which is useful for high-throughput and automated sample analysis. MALDI sample preparation …
Identification Of Quantitative Trait Loci Influencing Early Height Growth In Longleaf Pine (Pinus Palustris Mill), Lisha Wu
LSU Doctoral Dissertations
The delay in early height growth (EHG) has been a limiting factor for artificial regeneration of longleaf pine (Pinus palustris Mill.). Simple Sequence Repeat (SSR) markers have been used to map the genome and quantitative trait loci controlling the EHG in a backcross family (longleaf pine x slash pine) x longleaf pine. A total of 228 locus specific SSR markers were screened against 6 longleaf pine recurrent parents and a sample of 7 longlef x slash pine hybrid parents. In total, 135 polymorphic markers were identified. Based on the genetic variance in EHG, available sample size, and the number of …
Novel Devices And Protocols Enabling Isolation And Enumeration Of Low Abundant Biological Cells From Complex Matrices, Andre Antonio Adams
Novel Devices And Protocols Enabling Isolation And Enumeration Of Low Abundant Biological Cells From Complex Matrices, Andre Antonio Adams
LSU Doctoral Dissertations
The dimensions of microfluidic devices closely parallel those of biological cells; thusly, they are excellent platforms for the speciation, transport, manipulation, and analysis of cells. Electrokinetic transport of Escherichia coli and Saccharomyces cerevisiae was evaluated in microfluidic devices fabricated in pristine and UV-modified poly(methylmethacrylate) and polycarbonate. The magnitude and direction of transport of the cells was dictated by the buffer composition, conduit surface chemistry, and intrinsic cellular electrical properties. Baker’s yeast in all devices migrated toward the cathode, because of their smaller electrophoretic mobility compared to the electroosmotic flow of the polymer. E. coli cells suspended in 20 mM PBS …
Rational Approximation Schemes For Solutions Of Abstract Cauchy Problems And Evolution Equations, Patricio Gabriel Jara
Rational Approximation Schemes For Solutions Of Abstract Cauchy Problems And Evolution Equations, Patricio Gabriel Jara
LSU Doctoral Dissertations
In this dissertation we study time and space discretization methods for approximating solutions of abstract Cauchy problems and evolution equations in a Banach space setting. Two extensions of the Hille-Phillips functional calculus are developed. The first result is the Hille-Phillips functional calculus for generators of bi-continuous semigroups, and the second is a C-regularized version of the Hille-Phillips functional calculus for generators of C-regularized semigroups. These results are used in order to study time discretization schemes for abstract Cauchy problems associated with generators of bi-continuous semigroups as well as C-regularized semigoups. Stability, convergence results, and error estimates for rational approximation schemes …
Elucidating Marine Pore Water Exchange And Fresh Aquifer Sources In Estimates Of Submarine Groundwater Discharge To A Coastal Lagoon, Christopher Gerald Smith
Elucidating Marine Pore Water Exchange And Fresh Aquifer Sources In Estimates Of Submarine Groundwater Discharge To A Coastal Lagoon, Christopher Gerald Smith
LSU Doctoral Dissertations
Dynamic balances between fresh groundwater, saline groundwater, and surface water control the physics and chemistry of subterranean estuaries. Investigations were performed in a subterranean estuary on physical processes contributing to fresh groundwater and saline water mixing, vertical and lateral positioning of this mixing zone, and how this mixing affects spatial and temporal distributions of 234,238U, 226Ra, and 222Rn. The subterranean estuary is located in an unconfined aquifer beneath Indian River Lagoon, Florida, USA, where I could examine redox responses to altered flow regimes. Continuous groundwater and surface water level measurements suggest a strong hydrologic connection between this …
Generally Covariant Quantum Information, Stephan Jay Olson
Generally Covariant Quantum Information, Stephan Jay Olson
LSU Doctoral Dissertations
The formalism of covariant quantum theory, introduced by Reisenberger and Rovelli, casts the description of quantum states and evolution into a framework compatible with the principles of general relativity. The leap to this covariant formalism, however, outstripped the standard interpretation used to connect quantum theory to experimental predictions, leaving the predictions of the theory ambiguous. In particular, the absence of a pre-defined time variable or background causal structure resulted in an ``order of projections" ambiguity, in which the usual rule for multiple-measurement probabilities (obtained by time-ordered projections) is not defined. Equally troublesome, the probability postulate of Reisenberger and Rovelli fails …
Retro Models Of The Cisplatin-Dna Cross-Link With Carrier Ligands Having Sp2 N-Donor Triazine Rings, Vidhi Maheshwari
Retro Models Of The Cisplatin-Dna Cross-Link With Carrier Ligands Having Sp2 N-Donor Triazine Rings, Vidhi Maheshwari
LSU Doctoral Dissertations
Rapid rotation of guanine base derivatives about Pt–N7 bonds results in fluxional behavior of models of the key DNA intrastrand G–G cross-link leading to anticancer activity of Pt(II) drugs (G = deoxyguanosine). This behavior impedes the characterization of LPtG2 models (L = one bidentate or two cis-unidentate carrier ligands; G = guanine derivative). The objective of this study is to understand the types of conformers formed as L is systematically varied. This work, relevant to Pt(II) anticancer drugs, has evolved from published studies with sp3 N-ligands (e.g., 2,2'-bipiperidine), to C2 symmetrical or unsymmetrical sp2 N-ligands having pyridine and/or triazine rings. …
A Study Of Rheological And Thermodynamic Properties Of Polymer-Clay Gels And Multilayered Films, Eduard Adrian Stefanescu
A Study Of Rheological And Thermodynamic Properties Of Polymer-Clay Gels And Multilayered Films, Eduard Adrian Stefanescu
LSU Doctoral Dissertations
The overall objective of the research presented here is to understand the nanoscopic and microscopic structures that exist in dispersions of laponite and montmorillonite in poly(ethylene oxide), (PEO) and to correlate their shear responses with the final structure and properties of multilayered nanocomposite films prepared from these dispersions. These structures were examined as a function of polymer molecular weight, polymer and clay concentrations, and type of clay used to prepare the nanocomposites. A sequence of shear and elongational rheological measurements is used to provide a more complete physical picture on the structure of polymer-clay hydrogels, while a combination of techniques …
Exploration Of New Ternary Gallides And Investigation Of Their Structure-Property Relationships, Jung Young Cho
Exploration Of New Ternary Gallides And Investigation Of Their Structure-Property Relationships, Jung Young Cho
LSU Doctoral Dissertations
This dissertation focuses on the investigation of new ternary intermetallic gallides, which may exhibit exotic physical properties such as heavy-fermion behavior, large magnetoresistance, and even superconductivity. In particular, the Ln-Cu-Ga (Ln = lanthanides) system has been systematically investigated by changing a reaction ratio and/or using a different temperature profile to optimize desired phases. Single crystals of Ln2MGa12 (Ln = La, Ce; M = Ni, Cu) have been synthesized using Ga flux and compared to their Pd analogues. Interestingly, Ce2MGa12 (M = Ni, Cu) show enhanced Sommerfeld coefficient of ¡Ö 191 mJmol-1K-2 and ¡Ö 69 mJmol-1K-2 for Ni and Cu compounds, …
Towards An Extended Microscopic Theory For Upper-Fp-Shell Nuclei, Kalin Drumev
Towards An Extended Microscopic Theory For Upper-Fp-Shell Nuclei, Kalin Drumev
LSU Doctoral Dissertations
An extended SU(3) shell model that for the first time explicitly includes particles from the unique-parity levels in nuclei is introduced. Its relevance is established through calculations performed with realistic interactions for a group of upper fp-shell isotopes where valence nucleons beyond the N=28=Z core occupy levels of the normal-parity upper $fp$-shell ($f_{5/2},p_{3/2},p_{1/2}$) and the unique-parity $g_{9/2}$ intruder configuration. Specifically, the outcome suggests that the pseudo-SU(3) symmetry is quite good throughout the region and that only part of the configurations are relevant for the structure of the low-lying states. The levels of the upper $fp$-shell are handled within the framework …
Syntheses Of Trimethylamine- And Phosphonate- Substituted Carboranylporphyrins For Application In Boron Neutron Cancer Therapy, Michael William Easson
Syntheses Of Trimethylamine- And Phosphonate- Substituted Carboranylporphyrins For Application In Boron Neutron Cancer Therapy, Michael William Easson
LSU Doctoral Dissertations
Chapter 1 contains an introduction to porphyrins and carboranylporphyrins, including their physical properties, history, methods of synthesis, medicinal applications, and an overview of recently published compounds. Chapter 2 contains the total synthesis of a series of trimethylamine- and phosphonate-substituted carboranylporphyrins for application in boron neutron capture therapy (BNCT), including characterization by proton nuclear magnetic resonance spectroscopy, matrix-assisted time-of-flight mass spectroscopy, high resolution mass spectroscopy, UV-Vis spectrophotometry, X-ray crystallography, and melting point apparatus. Chapter 3 contains synthetic methods which were investigated as alternate routes to porphyrin synthesis and functionalization. Chapter 4 presents the in vitro biological evaluation of trimethylamine- and phosphonate-substituted …
Assessment Of Oxygen Sources And Sinks In The Northern Gulf Of Mexico Using Stable Oxygen Isotopes, Zoraida Jazmin Quinones-Rivera
Assessment Of Oxygen Sources And Sinks In The Northern Gulf Of Mexico Using Stable Oxygen Isotopes, Zoraida Jazmin Quinones-Rivera
LSU Doctoral Dissertations
Coastal hypoxia (< 2 mg O2L-1) represents a global problem that continues to worsen as nutrient fluxes to these areas increase. The second largest zone of human-induced hypoxia is located on the Louisiana continental shelf where hypoxic bottom waters commonly occur during summertime. This region is strongly impacted by the large flux of freshwater and nutrients from the Mississippi River, which influences both biological and physical processes that control oxygen dynamics. Yet, based on oxygen concentration measurements alone, it is difficult to separate the effects of biological factors from physical factors. To address this problem, I used a dual budget approach to assess the importance of oxygen sources and sinks on the Louisiana continental shelf. The dual budget was based on using stable oxygen isotopes (ä18O) in combination with conventional oxygen concentration measurements. To analyze temporal trends, surface and bottom water samples were collected monthly between July 2001 and July 2003 along an onshore-offshore transect. For better spatial resolution, shelfwide sampling was conducted extending from the Mississippi River Delta to the Louisiana-Texas border in the month of July of 2001, 2002, and 2003. Oxygen saturations values ranged between 180% at the surface and almost 0% close to the bottom with a corresponding range of ä18O values from 15‰ to 50‰. Biological parameters were important during all seasons for surface oxygen dynamics. The effects of physical factors were less apparent, except during severe physical disturbances. Bottom water oxygen dynamics showed clear seasonal signals of high oxygen depletion and larger contributions of benthic respiration during the summer, which corresponded to the strong stratification of the water column. In bottom waters, summer oxygen depletion was predominantly due to benthic respiration, accounting for about 73%, 80% and 60% of the total oxygen loss for 2001, 2002 and 2003 respectively. Model estimates of production/respiration (P/R) ratio during the July shelfwide cruises indicated that surface waters were productive with an average calculated P/R above 1. Depth stratified sampling (5 m intervals), which started in July 2002, showed that productivity in the mixed layer (5 to 10 m) was not homogeneous. Calculated P/R exceeded 1 only in the surface layer, while at 5 m P/R was approximately 1 and at a depth of 10 m, P/R was less than 1. Additionally, hypoxic conditions were only detected within 5 m of the bottom sediments. The dual budget approach yielded new estimates of productivity dynamics in surface waters and of sediment oxygen demand in bottom waters. For the first time, this study provided routine insight into productivity and respiration dynamics over large temporal and spatial scales. This could not have been accomplished using traditional methods because they commonly rely on time-consuming incubations. The study has shown that respiration dynamics in bottom waters vary seasonally with higher contribution of benthic respiration during stratified summer conditions and prevalent water column respiration during fall and winter. In contrast, seasonality in surface waters was less pronounced as productivity was more dependent on (salinity-inferred) nutrient supply than climatic forcing.
Bioanalytical Methods For Studies Of Homocysteine And Novel Cardiovascular Disease Indicators, Arther T. Gates
Bioanalytical Methods For Studies Of Homocysteine And Novel Cardiovascular Disease Indicators, Arther T. Gates
LSU Doctoral Dissertations
This dissertation explores the development of analytical methods for studies of CVD biomarkers and related biomolecular indicators. Initially, spectroscopic studies were conducted to investigate the chemical reactivity of homocysteine (Hcy), an independent CVD risk factor and serological biomarker. Consequently, we proposed an alternate theory for in vivo Hcy clearance based on spontaneous pyridoxal tetrahydrothiazine (PT) formation from Hcy and pyridoxal. The validity of PT-assisted Hcy clearance was further evaluated by use of capillary electrophoretic methods, which allowed rapid monitoring of protein oligomerization in PT-protein reaction mixtures. The results of these studies suggest that PT formation is a plausible mechanism for …
Investigation Of Superconductivity And Physical Properties Of Intermetallic Compounds: Mon, Mo₃Sb₇, Mgcni₃ And Transition Metal Diborides, Amar Bahadur Karki
Investigation Of Superconductivity And Physical Properties Of Intermetallic Compounds: Mon, Mo₃Sb₇, Mgcni₃ And Transition Metal Diborides, Amar Bahadur Karki
LSU Doctoral Dissertations
In this dissertation work, I report on the interesting results of our detailed investigations of the synthesis, structural, electrical and magnetic characterization of three different classes of intermetallic systems. Mo3Sb7 wires, thin films and microfibers exhibit the highest Tc ~ 8 K, which is substantially higher than the 2.2 K reported for the single crystal and powder of Mo3Sb7. The suppression of the spin fluctuations in Mo3Sb7 is evident by the absence of a parabolic dependence of magnetic susceptibility at 1 T. MoN wires, thin films and coated microfibers …
Investigation Of Antimonide Structure Types And The Structural Studies Of Molybdates, Dixie Plaisance Gautreaux
Investigation Of Antimonide Structure Types And The Structural Studies Of Molybdates, Dixie Plaisance Gautreaux
LSU Doctoral Dissertations
This dissertation highlights the investigation of ternary lanthanide antimonide structure types and their physical properties. In particular, these ternary phases allow for the systematic investigation of the structure in an effort to correlate structure and properties. The ternary antimonides are layered structures with two-dimensional square sheets or nets, which influence the properties of these materials. In an effort to determine how structural changes influence the physical properties, various single crystals of compounds relating to the orthorhombic CeNiSb3 structure have been grown and characterized. The layered CeNiSb3 structure consists of Sb sheets, NiSb6 distorted octahedra, and CeSb9 monocapped square anti-prisms. LnNi(Sn,Sb)3 …
Concentration Of Phosphorylated Proteins Using Modified Pmma Microanalytical Devices, Jowell Guerra Bolivar
Concentration Of Phosphorylated Proteins Using Modified Pmma Microanalytical Devices, Jowell Guerra Bolivar
LSU Doctoral Dissertations
This work describes the application of PMMA-based microanalytical devices for the affinity-type preconcentration of posttranslational modified proteins (PTMs). The choice of poly(methyl methacrylate), PMMA, is based on its biocompatibility, its functional methyl ester group for potential modification, and its extensive applications to create biological microelectromechanical systems (BioMEMS). Developing methodologies for preconcentration of PTMs is important for cancer diagnosis due to PTMs’ influence in the regulatory mechanism underlying the early stage of apoptosis or regulated cell death. Towards this goal, nitroavidin which can reversibly binds to biotin (and biotinylated proteins), was prepared using reported procedure and was characterized using several techniques …
Solid-Phase Synthesis Of Asymmetrically Substituted Phthalocyanines, Sultan Sibel Erdem
Solid-Phase Synthesis Of Asymmetrically Substituted Phthalocyanines, Sultan Sibel Erdem
LSU Doctoral Dissertations
Phthalocyanines (Pcs) are excellent candidates for use as fluorophores for near-infrared (near-IR) fluorescent tagging of biomolecules and as photodynamic therapy (PDT) agents. Synthesis of Pcs with asymmetrical substitution on the periphery is often difficult due to the problems during the purification of the Pc mixtures obtained. The objective of this project is to design and synthesize chemically robust near-IR fluorophores for bioanalytical applications and to develop new synthetic methods for rapid synthesis of the target compounds. A novel synthetic route was developed utilizing a hydrophilic, polyethylene glycol-based (PEG) support with different types of linkers. The Pcs were functionalized with either …
The Synthesis Of Water Soluble N-Acyl Chitosan Derivatives For Characterization As Antibacterial Agents, Lakia Monique Champagne
The Synthesis Of Water Soluble N-Acyl Chitosan Derivatives For Characterization As Antibacterial Agents, Lakia Monique Champagne
LSU Doctoral Dissertations
Currently, natural polysaccharides are being utilized increasingly in the markets because they exhibit biodegradability, biocompatibility, versatility, and are found abundant in nature. The diversity of natural polysaccharides provides the chemist with a broad spectrum of raw materials that can be used in many biological applications. Chitosan is a natural polysaccharide that possesses excellent biological properties. It has been recognized for its antibacterial activity, in that it is destructive towards the bacterium Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The antibacterial property of chitosan can be enhanced by changing the hydrophobic/hydrophilic nature of the polysaccharide backbone. This research entails …
Surgery Description Of Colored Knots, Steven Daniel Wallace
Surgery Description Of Colored Knots, Steven Daniel Wallace
LSU Doctoral Dissertations
By a knot, or link, we mean a circle, or a collection of circles, embedded in the three-sphere S3. The study of knots is a very rich subject and plays a key role in the area of low-dimensional topology. In fact, a theorem of W.B.R. Lickorish and A.D. Wallace states that any three-dimensional manifold may be described by Dehn surgery along a link which is the process of removing the link from S3 and then gluing it back in a way that possibly changes the resulting manifold. In this dissertation, we will be interested in the pair (K, ρ) consisting …