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Microassembly Technology For Modular, Polymer Microfluidic Devices, Byoung Hee You
Microassembly Technology For Modular, Polymer Microfluidic Devices, Byoung Hee You
LSU Doctoral Dissertations
Assembly of modular, polymer microfluidic devices with different functions to obtain more capable instruments may significantly expand the options available for detection and diagnosis of disease through DNA analysis and proteomics. For connecting modular devices, precise, passive alignment structures can be used to prevent infinitesimal motions between the devices and minimize misalignment. The motion and constraint of passive alignment structures were analyzed using screw theory. A combination of three v-groove and hemisphere-tipped post joints constrained all degrees of freedom of the two mating modules without overconstraint. Simulations and experiments were performed to assess the predictability of dimensional and location variations …
Designing Surface Chemistries For In Situ Afm Investigations Of Biomolecular Reactions With Proteins At The Nanoscale, Johnpeter Ndiangui Ngunjiri
Designing Surface Chemistries For In Situ Afm Investigations Of Biomolecular Reactions With Proteins At The Nanoscale, Johnpeter Ndiangui Ngunjiri
LSU Doctoral Dissertations
In situ atomic force microscopy (AFM) characterizations and lithography can be applied to investigate the orientation, reactivity and stability of protein molecules adsorbed on nanostructures of self-assembled monolayers at near-physiological conditions. Automated nanografting was used to fabricate regular arrays of nanopatterns of ù-functionalized n-alkanethiols with designated terminal chemistries. After writing nanopatterns, protein binding occurs selectively on carboxylate-terminated nanopatterns via covalent bonds that are formed using N-ethyl-N'(dimethylaminoporpyl)-carbodiimide and N-hydroxysuccinimide activation. The amine groups of lysine residues of proteins bond covalently to nanopatterns of carboxylate-terminated alkanethiol self-assembled monolayers, to form a robust surface attachment for sustained contact-mode AFM imaging during biochemical reactions. …
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 …
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 …
A Study Of Regret And Rejoicing And A New Mcdm Method Based On Them, Xiaoting Wang
A Study Of Regret And Rejoicing And A New Mcdm Method Based On Them, Xiaoting Wang
LSU Doctoral Dissertations
Multi-criteria decision-making (MCDM) is one of the most widely used decision methodologies in the sciences, business, and engineering worlds. MCDM methods aim at improving the quality of decisions by making the process more explicit, rational, and efficient. One controversial problem is that some well-known MCDM methods, like the additive AHP methods and the ELECTRE II and III methods, may cause some types of rank reversal problems. Rank reversal means that the ranking between two alternatives might be reversed after some variation occurs to the decision problem, like adding a new alternative, dropping an old alternative or replacing a non-optimal alternative …
Numerical Modeling Of Continuous Flow Microwave Heating - Coupling Of High Frequency Electromagnetism With Fluid Flow And Heat Transfer, Deepti Salvi
LSU Doctoral Dissertations
This study focused on numerical and experimental investigation of continuous flow microwave heating. A numerical model was developed to predict the temperature of a liquid product heated in a continuous-flow focused microwave system by coupling electromagnetism, fluid flow, and heat transfer in two different software packages (ANSYS Multiphysics 9.0 and COMSOL Multiphysics 3.4). The temperature and energy distributions simulated in ANSYS were verified against other numerical studies published in the literature. Comparison of the simulated temperature in ANSYS with experimental data for salt water of two different salinities showed good agreement. To simulate the experimental conditions more accurately, a comprehensive …
Optimization Of Treatment Of Chlorinated Volatile Organic Compound Mixtures In Constructed Wetlands: Vegetation And Substrate Effects, Stephen Emmanuel Mbuligwe
Optimization Of Treatment Of Chlorinated Volatile Organic Compound Mixtures In Constructed Wetlands: Vegetation And Substrate Effects, Stephen Emmanuel Mbuligwe
LSU Doctoral Dissertations
Microcosm and mesocosm scale experiments were carried out to investigate the effects of vegetation and substrates on the performance of engineered wetland systems (EWSs) meant to treat mixtures of volatile organic compounds (cVOCs). The experiments were conducted with a view to optimizing contributions of these wetland components. Phragmites communis and Typha latifolia, the commonest wetland plant species, were compared in mesocosm scale EWSs. Eight common wetland plant species were compared using microcosm experiments based on the potential of their rootmatter to enhance treatment of cVOC mixtures. Twelve common wetland plants were similarly compared but on the basis of their aboveground …
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).
Syntheses And Evaluation Of Phthalocyanine Derivatives For Applications In Photodynamic And Boron Neutron Capture Therapies For Cancer, Hairong Li
LSU Doctoral Dissertations
Chapter I introduced the background of phthalocyanines including its physical properties and various synthetic methods of free-base and metallo-phthalocyanines. The background of PDT and BNCT was introduced and the objective of ideal sensitizers was described. Chapter II described the synthesis and characterization of a series of pyridiloxy-substituted zinc phthalocyanines with different length of alkyl groups. Pyridiloxy-substituted silica phthalocyanines bearing different associated axial ligands, were alkylated with methyl or PEG chains. Biological study was performed on these cationic pyridiloxy-substituted zinc phthalocyanines. Chapter III introduced the synthesis and photophysical properties of A3B-type zinc phthalocyanines conjugated with one or two cobalta-carborane cages. They …
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 …
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.
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 …
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 …
Speaking The Language Of Integration: A Case Study Of South Boulevard Foreign Language Academic Immersion Magnet, Heather Kathleen Olson Beal
Speaking The Language Of Integration: A Case Study Of South Boulevard Foreign Language Academic Immersion Magnet, Heather Kathleen Olson Beal
LSU Doctoral Dissertations
Racial segregation and an achievement gap persist despite the promises of Brown vs. Board of Education (1954). In Baton Rouge, Louisiana, public schools are 83% Black, while nearly one-third of all children attend private schools which are 86% White. South Boulevard (SB) Foreign Language Academic Immersion Magnet Elementary is a counterexample because it has achieved integration and academic achievement well above district and state averages on high stakes tests. This research explores the culture of SB’s immersion magnet program in relation to its success as an integrated public school with high student achievement and explores the factors that motivated a …
A Symphonic Poem On Dante's Inferno And A Study On Karlheinz Stockhausen And His Effect On The Trumpet, Michael Joseph Berthelot
A Symphonic Poem On Dante's Inferno And A Study On Karlheinz Stockhausen And His Effect On The Trumpet, Michael Joseph Berthelot
LSU Doctoral Dissertations
The first portion of this dissertation is an original composition A Symphonic Poem on Dante’s Inferno. This symphonic poem is in three movements: I. The Dream, depicts Dante falling asleep and describes the beginning of the Inferno, II. The Journey, depicts Virgil and Dante walking towards the Gates of Hell, III. Hell’s Depths; explores Hell’s Gates, the Souls of Limbo and the Nine Circles of Hell. Dante realizes at the age of thirty-five that he has wandered into the Dark Wood of Error. As soon as he realizes his loss, Dante lifts his eyes and sees the first light, lighting …
Revolutionizing Genomic Analyses: Mutation Analyses Using Novel Enzyme-Based Assays With Laser-Induced Fluorescence And Polymeric Microfluidic Devices As Electrophoretic Platforms, Rondedrick Deshaun Sinville
Revolutionizing Genomic Analyses: Mutation Analyses Using Novel Enzyme-Based Assays With Laser-Induced Fluorescence And Polymeric Microfluidic Devices As Electrophoretic Platforms, Rondedrick Deshaun Sinville
LSU Doctoral Dissertations
Polymer-based microelectrophoresis was investigated to analyze known (mutation detection) and unknown (mutation scanning) low-abundant mutations in genomic DNA with high diagnostic value for colorectal cancers. For our mutation detection assays, point mutations in the K-ras oncogene were identified using the ligase detection reaction (LDR). For the mutation scanning assay, which searches for sporadic mutations, an EndoV-LDR assay was utilized with mutations in the p53 tumor suppressor gene used as a model. A poly(methylmethacrylate), PMMA, microchip filled with a 4% linear polyacrylamide (LPA) gel was used to electrophoretically sort products formed from LDRs, which produced oligonucleotides <65 bp in length. Using microchip electrophoresis with the LPA, a 44 bp ligation product was resolved from a 100-fold molar excess of unligated primers (25 bp) in approximately 120 s, which was ~17 times faster than conventional capillary gel electrophoresis. In order to simplify the electrophoretic process and further reduce development time, the LDR products were sorted in the absence of the sieving gel using free solution conjugate electrophoresis (FSCE). FSCE incorporated polyamide “drag-tags” onto LDR primers, which provided DNA fragment mobilities in free solution that were dependent upon their size. LDR/drag-tagged (LDR-dt) products could be formed in a multiplexed format for mutant-to-wild-type ratios as low as 1 to 100 with single base resolution. Separations were conducted using capillary array electrophoresis (CAE) and PMMA microchips filled with only a TRIS buffer. Analysis times for the LDR-dt products were less than 11 min using CAE and ~85 s for PMMA microchips with high reproducible migration times within and between microchips. PMMA-based microchips were also evaluated for the identification of sporadic mutations using an endonuclease V – LDR (Endo V/LDR) technique. Endo V cleaves heteroduplexed DNA one base 3’ of single-base mismatched sites as well as nicking DNA at some matched sites as LDR reseals miscleaved sites to reduce false positive signals. Results suggested that Endo V/LDR products from p53 mutations could be successfully separated and detected using a PMMA microfluidic chip filled with a sparsely cross-linked replaceable polyacrylamide gel in less than 6 min, which was approximately 10-fold shorter compared to CAE.
Differential Geometry In Cartesian Closed Categories Of Smooth Spaces, Martin Laubinger
Differential Geometry In Cartesian Closed Categories Of Smooth Spaces, Martin Laubinger
LSU Doctoral Dissertations
The main categories of study in this thesis are the categories of diffeological and Fr\"olicher spaces. They form concrete cartesian closed categories. In Chapter 1 we provide relevant background from category theory and differentiation theory in locally convex spaces. In Chapter 2 we define a class of categories whose objects are sets with a structure determined by functions into the set. Fr\"olicher's $M$-spaces, Chen's differentiable spaces and Souriau's diffeological spaces fall into this class of categories. We prove cartesian closedness of the two main categories, and show that they have all limits and colimits. We exhibit an adjunction between the …
Development Of New Stimuli-Responsive Vesicles Using A Novel Surfactant, Yuming Yang
Development Of New Stimuli-Responsive Vesicles Using A Novel Surfactant, Yuming Yang
LSU Doctoral Dissertations
Many amphiphilic molecules (surfactants) possess the ability to aggregate in aqueous solution to form thermodynamically stable aggregates that have potential for use as molecule containers and delivery systems in analytical or pharmaceutical applications. However, it is difficult to release the encapsulated molecules from these aggregates under a controllable manner, and this problem has dramatically limited the application of these aggregated systems. This study addresses this problem through fundamental structure modification by development of a novel redox stimuli-responsive amphiphile capable of forming vesicle aggregates. Aggregate structure can be adjusted through redox stimulation. The release of agents from the core of the …
Reservoir Characterization Using Seismic Inversion Data, Subhash Kalla
Reservoir Characterization Using Seismic Inversion Data, Subhash Kalla
LSU Doctoral Dissertations
Reservoir architecture may be inferred from analogs and geologic concepts, seismic surveys, and well data. Stochastically inverted seismic data are uninformative about meter-scale features, but aid downscaling by constraining coarse-scale interval properties such as total thickness and average porosity. Well data reveal detailed facies and vertical trends (and may indicate lateral trends), but cannot specify intrawell stratal geometry. Consistent geomodels can be generated for flow simulation by systematically considering the precision and density of different data. Because seismic inversion, conceptual stacking, and lateral variability of the facies are uncertain, stochastic ensembles of geomodels are needed to capture variability.
In this …
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.
An Investigation Into Fuel Cells And Flow Cytometers Optimal Design, Etim Sunday Udoetok
An Investigation Into Fuel Cells And Flow Cytometers Optimal Design, Etim Sunday Udoetok
LSU Doctoral Dissertations
The aim of the fuel cells part of this project was to investigate the performance of Proton Exchange Membrane Fuel Cells and closely related fuel cell types like the Alkaline Fuel Cells and Phosphoric Acid Fuel Cells. The investigation involved understanding the performance of fuel cells, addressing the shortcomings of currently used designs, and finding new methods for improving the performance of fuel cells. CFD was used to study flow channels and information learned from the study was used to design a new and improved flow channel. A prototype of the new design was fabricated, tested and found to perform …
The Role Of Attentional Focus In Event-Based Prospective Memory, Jill Shelton
The Role Of Attentional Focus In Event-Based Prospective Memory, Jill Shelton
LSU Doctoral Dissertations
Shelton, Jill, B.S., University of Tennessee-Chattanooga, 2001 M.S., University of Tennessee-Chattanooga, 2003 Doctor of Philosophy, Summer Commencement, 2008 Major: Psychology The Role of Attentional Focus in Event-based Prospective Memory. Dissertation directed by Professor Emily Elliott Pages in dissertation, 59. Words in abstract 188. ABSTRACT Two experiments were conducted to investigate how attentional resources are utilized in event-based prospective memory (PM). A PM component (make a designated response when you see a bird word) was embedded in a living/non-living judgment task (Experiment 1) and a recall task that required participants to alphabetically re-order sets of items (Experiment 2). One hypothesis predicts …
A Century Of Land Use And Water Quality In Watersheds Of The Continental U.S., Whitney P. Broussard Iii
A Century Of Land Use And Water Quality In Watersheds Of The Continental U.S., Whitney P. Broussard Iii
LSU Doctoral Dissertations
Human endeavors, particularly the agricultural and industrial activities of the last half century, now produce more biologically available nitrogen (N) than all other natural sources combined. The increased N availability can have consequences for the health of aquatic biota on the local, regional, and global scales. One manifestation of this problem is the formation of coastal hypoxic zones where terrestrial N loading creates eutrophic conditions in coastal waters. This dissertation examines a century of changes in land use and water quality to quantify the relationships between agricultural land use practices and riverine N yields in the Mississippi River Basin and …
Academic Impropriety: Violation Of Normative Teaching Behaviors As Identified By Nursing Educators, Melanie Hilburn Green
Academic Impropriety: Violation Of Normative Teaching Behaviors As Identified By Nursing Educators, Melanie Hilburn Green
LSU Doctoral Dissertations
With public criticism of American higher education on the rise, it is prudent for those in the academy to reflect upon their responsibilities to their students. Of particular salience is an examination of what constitutes misconduct within the faculty role. This dissertation reports the results of a study designed to identify what nursing educators believe to be the violation of normative teaching behaviors. A sequential explanatory mixed methods design was utilized to develop an understanding of the actions that constitute academic impropriety. The College Teaching Behaviors Inventory, a survey instrument designed by Braxton and Bayer (1999), was distributed to deans …
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 …
Digital Storytelling As A Literacy-Based Intervention For A Sixth Grade Student With Autism Spectrum Disorder: An Exploratory Case Study, Brent A. Daigle
Digital Storytelling As A Literacy-Based Intervention For A Sixth Grade Student With Autism Spectrum Disorder: An Exploratory Case Study, Brent A. Daigle
LSU Doctoral Dissertations
This study investigates the use of Digital Storytelling as an intervention to improve the academic performance and social interactions of a sixth grade student with High-Functioning Autism. Qualitative methodology, using an inductive approach informed by grounded theory, was employed throughout this exploratory case study. Three separate data sources, consisting of document analysis, interviews, and participant observation, contributed to the findings of this study. Triangulation of inquiry methods enhanced the validity and rigor of this investigation. The findings from this inquiry indicate that Digital Storytelling was beneficial to the participant in this exploratory case study. Engaged student processes and critical analysis …