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2012

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Articles 8461 - 8490 of 8516

Full-Text Articles in Physical Sciences and Mathematics

Improved Potential Energy Surface Of Ozone Constructed Using The Fitting By Permutationally Invariant Polynomial Function, M. Ayouz, Dmitri Babikov Jan 2012

Improved Potential Energy Surface Of Ozone Constructed Using The Fitting By Permutationally Invariant Polynomial Function, M. Ayouz, Dmitri Babikov

Chemistry Faculty Research and Publications

New global potential energy surface for the ground electronic state of ozone is constructed at the complete basis set level of the multireference configuration interaction theory. A method of fitting the data points by analytical permutationally invariant polynomial function is adopted. A small set of 500 points is preoptimized using the old surface of ozone. In this procedure the positions of points in the configuration space are chosen such that the RMS deviation of the fit is minimized. New ab initio calculations are carried out at these points and are used to build new surface. Additional points are added to …

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Pmi 5011 Regulates The Ubiquitin Proteasome System In Skeletal Muscle, Heather Christianne Kirk-Ballard Jan 2012

Pmi 5011 Regulates The Ubiquitin Proteasome System In Skeletal Muscle, Heather Christianne Kirk-Ballard

LSU Doctoral Dissertations

Insulin resistance in type 2 diabetes is associated with impaired glucose and protein metabolism in skeletal muscle. The impaired insulin signaling in skeletal muscle affects muscle mass by tilting the balance between skeletal muscle protein synthesis and degradation toward degradation, a process that is primarily regulated by the ubiquitin-proteasome system. Studies have shown that an extensively characterized ethanol extract of Artemisia dracunculus L (Russian Tarragon), termed PMI 5011, enhances insulin signaling in human primary skeletal muscle cells and in a rodent model of insulin resistance. The aim of this project is to determine if the effect of PMI 5011 on …

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Chemical Crystallography At The Interface Of Physics, Chemistry, And In Engineering: Structure Determination Of Highly Correlated Extended Solids, Main Group Compounds, Coordination Complexes, And Bioceramics, Gregory Todd Mccandless Jan 2012

Chemical Crystallography At The Interface Of Physics, Chemistry, And In Engineering: Structure Determination Of Highly Correlated Extended Solids, Main Group Compounds, Coordination Complexes, And Bioceramics, Gregory Todd Mccandless

LSU Doctoral Dissertations

Multi-disciplinary research is essential to address the major challenges in science, engineering, and medicine. For these three areas, crystallography has played and continues to play a huge role by providing researchers with the means to determine the structure of a compound and relate these to its properties. This dissertation is highly interdisciplinary, focusing on structure determination of complex systems and materials with tailored applications. This work includes the characterization by single crystal and powder X-ray diffraction of intermetallic extended solids, layered metal oxides, inorganic complexes, discrete organic molecules, and bioceramics. These projects range from modeling translational disorder with pseudo-hexagonal symmetry …

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Some Tracking Problems For Aerospace Models With Input Constraints, Aleksandra Gruszka Jan 2012

Some Tracking Problems For Aerospace Models With Input Constraints, Aleksandra Gruszka

LSU Doctoral Dissertations

We study tracking controller design problems for key models of planar vertical takeoff and landing (PVTOL) aircraft and unmanned air vehicles (UAVs). The novelty of our PVTOL work is the global boundedness of our controllers in the decoupled coordinates, the positive uniform lower bound on the thrust controller, the applicability of our work to cases where the velocity measurements may not be available, the uniform global asymptotic stability and uniform local exponential stability of our closed loop tracking dynamics, the generality of our class of trackable reference trajectories, and the input-to-state stability of the controller performance under actuator errors of …

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Identification And Incorporation Of Quantitative Indicators Of Ecosystem Function Into Single-Species Fishery Stock Assessment Models And The Associated Biological Reference Points, Melissa Hedges Monk Jan 2012

Identification And Incorporation Of Quantitative Indicators Of Ecosystem Function Into Single-Species Fishery Stock Assessment Models And The Associated Biological Reference Points, Melissa Hedges Monk

LSU Doctoral Dissertations

The move towards an ecosystem approach to fisheries management requires baseline information on the biotic communities and an understanding of the interactions among species. The two objectives of this study were to describe the demersal fish community (DFC) associated with the northwestern Gulf shrimp trawl fishery, and to utilize a multispecies Lotka-Volterra model to examine possible community level effects of fishing. Community level effects include predator-prey interactions and the responses of fish in the same community to fishing pressure. The summer and fall Southeast Area Monitoring and Assessment Program (SEAMAP) bottomfish trawl surveys were used to identify spatial and temporal …

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Chemical And Biological Evaluation Of Antibiotic-Based Ionic Liquids And Gumbos Against Pathogenic Bacteria, Marsha Rae Cole Jan 2012

Chemical And Biological Evaluation Of Antibiotic-Based Ionic Liquids And Gumbos Against Pathogenic Bacteria, Marsha Rae Cole

LSU Doctoral Dissertations

The research presented in this dissertation explores a novel pragmatic therapeutic approach for control, prevention, and treatment of infectious disease using Active-Pharmaceutical Ingredient-based Ionic Liquids (API-ILs) and Groups of Uniform Materials Based on Organic Salts (GUMBOS). Accordingly, several antiseptic- and antibiotic-based API-ILs and GUMBOS were synthesized and characterized using a combination of analytical and microbiological techniques. Overall, this research presents an advanced alternative to combination antibiotic therapy by using a novel group of ionic antimicrobial materials that have controlled pharmacokinetics, improved bioavailabilities, reduced toxicities, multi-modal properties, and potent antimicrobial spectrum of activity as a viable alternative to combating bacterial infections. …

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Hypercube Diagrams For Knots, Links, And Knotted Tori, Ben Mccarty Jan 2012

Hypercube Diagrams For Knots, Links, And Knotted Tori, Ben Mccarty

LSU Doctoral Dissertations

For a knot K the cube number is a knot invariant defined to be the smallest n for which there is a cube diagram of size n for K. Examples of knots for which the cube number detects chirality are presented. There is also a Legendrian version of this invariant called the Legendrian cube number. We will show that the Legendrian cube number distinguishes the Legendrian left hand torus knots with maximal Thurston-Bennequin number and maximal rotation number from the Legendrian left hand torus knots with maximal Thurston-Bennequin number and minimal rotation number. Finally, there is a generalization of cube …

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Entanglement, Uncertainty And Relativity In Fundamental Mechanics With An Application In Qkd, Christopher David Richardson Jan 2012

Entanglement, Uncertainty And Relativity In Fundamental Mechanics With An Application In Qkd, Christopher David Richardson

LSU Doctoral Dissertations

In this dissertation I will probe the innate uncertainty of quantum mechanics. After deriving the necessary tools I will tackle Popper's experiment, a long misunderstood thought experiment with recent experimental results. I will then discuss how uncertainty changes when making measurements from different relativistic reference frames and resolve some on the tension between quantum mechanics and relativity. Finally I utilize the practical aspect of quantum uncertainty and describe a practical quantum key distribution scheme.

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Developing A Geospatial Protocol For Coral Epizootiology, Jennifer Anne Lentz Jan 2012

Developing A Geospatial Protocol For Coral Epizootiology, Jennifer Anne Lentz

LSU Doctoral Dissertations

This dissertation explores how geographic information systems (GIS) and spatial statistics, specifically the techniques used to map, detect, and spatially analyze disease epidemics, could be used to advance our understanding of coral reef health. Given that different types of spatial analysis, as well as different parameter settings within each analysis, can produce noticeably different results, poor selection or improper use of a given technique would likely lead to inaccurate representations of the spatial distribution and false interpretations of the disease. For this reason, I performed a comprehensive review of the following types of exploratory spatial data analysis (ESDA): mapping and …

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On The Witt Groups Of Schemes, Jeremy Allen Jacobson Jan 2012

On The Witt Groups Of Schemes, Jeremy Allen Jacobson

LSU Doctoral Dissertations

We consider two questions about the Witt groups of schemes: the first is the question of finite generation of the shifted Witt groups of a smooth variety over a finite field; the second is the Gersten conjecture. Regarding the first, we prove that the shifted Witt groups of curves and surfaces are finite, and that finite generation of the motivic cohomology groups with mod 2 coefficients implies finite generation of the Witt groups. Regarding the second, we prove the Gersten conjecture for the Witt groups in the case of a local ring that is essentially smooth over a discrete valuation …

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Synthesis And Characterization Of Red And Near-Infrared Bodipy-Based Fluorophores For Various Biological Applications, Timsy Kaur Uppal Jan 2012

Synthesis And Characterization Of Red And Near-Infrared Bodipy-Based Fluorophores For Various Biological Applications, Timsy Kaur Uppal

LSU Doctoral Dissertations

ABSTRACT 4,4-Difluoro-3a,4a-diaza-s-indacene, better known as BODIPY® dyes, have attracted considerable attention due to their intriguing physicochemical and spectral properties, including high absorption coefficient, fluorescence quantum yield and good photochemical stability. Despite the recent progress achieved in this field, the synthesis of BODIPY derivatives that absorb and emit in the red- and NIR-region of the electromagnetic spectrum and their application to biomolecular targets, represents a long-standing challenge in BODIPY chemistry. This research work is therefore focused on the synthesis and characterization of red and NIR-emissive BODIPY-based fluorophores for various bioanalytical and biomedical applications. Chapter 1 of this dissertation represents a concise …

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Resonance And Double Negative Behavior In Metamaterials, Yue Chen Jan 2012

Resonance And Double Negative Behavior In Metamaterials, Yue Chen

LSU Doctoral Dissertations

In this work, a generic class of metamaterials is introduced and is shown to exhibit frequency dependent double negative effective properties. We develop a rigorous method for calculating the frequency intervals where either double negative or double positive effective properties appear and show how these intervals imply the existence of propagating Bloch waves inside sub-wavelength structures. The branches of the dispersion relation associated with Bloch modes are shown to be explicitly determined by the Dirichlet spectrum of the high dielectric phase and the generalized electrostatic spectra of the complement. For numerical purposes, we consider a metamaterial constructed from a sub-wavelength …

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Cluster Based Jamming And Countermeasures For Wireless Sensor Network Mac Protocols, David Trammell Jan 2012

Cluster Based Jamming And Countermeasures For Wireless Sensor Network Mac Protocols, David Trammell

LSU Doctoral Dissertations

A wireless sensor network (WSN) is a collection of wireless nodes, usually with limited computing resources and available energy. The medium access control layer (MAC layer) directly guides the radio hardware and manages access to the radio spectrum in controlled way. A top priority for a WSN MAC protocol is to conserve energy, however tailoring the algorithm for this purpose can create or expose a number of security vulnerabilities. In particular, a regular duty cycle makes a node vulnerable to periodic jamming attacks. This vulnerability limits the use of use of a WSN in applications requiring high levels of security. …

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On The Synthesis, Characterization, And Magnetization Of Ln-M-X (Ln = Lanthanide; M = Ti-Cr, Cu, Mo, Pd; X = Al, Ga) Intermetallics, Michael James Kangas Jan 2012

On The Synthesis, Characterization, And Magnetization Of Ln-M-X (Ln = Lanthanide; M = Ti-Cr, Cu, Mo, Pd; X = Al, Ga) Intermetallics, Michael James Kangas

LSU Doctoral Dissertations

The focus of the research presented herein was to grow single crystals of Ln-M-X (Ln = lanthanide; M = Ti-Cr, Cu, Mo, Pd; X = Al, Ga) intermetallic compounds and to characterize their crystal structures and physical properties. Overall, the flux growth technique facilitated a detailed analysis of previously known structure-types (LnM2Al20 (Ln = La, Ce, Pr, Yb; M = Ti, V, Cr), Ln6M4Al43 (Ln = Gd, Yb; M = Cr, Mo), and Yb2Pd3Ga9), as well as the synthesis and characterization of new compounds (LnCrxGa3 (Ln = Ho, Er; x ~ 0.13), YbCr2Al20-xFex (x ~ 0.2), Ln(Cu,Al,Ga)13-x, and Ln2PdGa12 (Ln …

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Visualization Of Time-Varying Data From Atomistic Simulations And Computational Fluid Dynamics, Bidur Bohara Jan 2012

Visualization Of Time-Varying Data From Atomistic Simulations And Computational Fluid Dynamics, Bidur Bohara

LSU Doctoral Dissertations

Time-varying data from simulations of dynamical systems are rich in spatio-temporal information. A key challenge is how to analyze such data for extracting useful information from the data and displaying spatially evolving features in the space-time domain of interest. We develop/implement multiple approaches toward visualization-based analysis of time-varying data obtained from two common types of dynamical simulations: molecular dynamics (MD) and computational fluid dynamics (CFD). We also make application case studies. Parallel first-principles molecular dynamics simulations produce massive amounts of time-varying three-dimensional scattered data representing atomic (molecular) configurations for material system being simulated. Rendering the atomic position-time series along with …

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Linking Nitrogen Biogeochemistry To Different Stages Of Wetland Soil Development In The Mississippi River Delta, Louisiana, Kelly Marie Henry Jan 2012

Linking Nitrogen Biogeochemistry To Different Stages Of Wetland Soil Development In The Mississippi River Delta, Louisiana, Kelly Marie Henry

LSU Doctoral Dissertations

Extensive wetland loss and nutrient-enhanced eutrophication occur across the Mississippi River delta and include newly emergent landscapes, in the early stages of ecological succession, and older landscape formations, with fully developed ecological communities. Here I tested how the anthropogenic effects of a climate-induced vegetation shift, an oil spill, and nitrate-enrichment regulate the principal environmental factors controlling nutrient biogeochemistry in wetland soils at different stages of development throughout the Mississippi River delta. In the older, transgressing Barataria basin, there was no clear effect of the climate-induced species shift from Spartina alterniflora Loisel to Avicennia germinans L. on soil nutrient chemistry. Observed …

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A Numerical Investigation Of Apéry-Like Recursions And Related Picard-Fuchs Equations, Maiia J. Bakhova Jan 2012

A Numerical Investigation Of Apéry-Like Recursions And Related Picard-Fuchs Equations, Maiia J. Bakhova

LSU Doctoral Dissertations

In this work we investigate a generalization of a recursion which was used by Apery in his proof of irrationality of the zeta function values at 2 and 3. It is a continuation of the work of Zagier , who considered generalization of the first equation and numerically investigated it. The study is made for two generalizations of the second equation, one used the mirror symmetry idea from the theory of Calabi-Yau varieties and another worked with recursion. There were discovered connections between them.

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Total Synthesis Of A Virotoxin And Analogs For Conformational Studies, Benson Jumba Edagwa Jan 2012

Total Synthesis Of A Virotoxin And Analogs For Conformational Studies, Benson Jumba Edagwa

LSU Doctoral Dissertations

This dissertation describes the first total synthesis of alloviroidin in trace amounts, along with that of three analogs containing L-proline (Pro), trans-3-hydroxyproline (3-Hyp) or cis-4-hydroxyproline (4-hyp) residue substituting for 2,3-trans-3,4-trans-dihydroxyproline in the natural product. We report herein an efficient strategy that provides a dipeptide containing a (2S,4S)-4,5-dihydroxyleucine (dihyLeu) residue, including a diastereoselective dihydroxylation. Nα-Carbobenzyloxy-(2S)-4,5-dehydroleucine was coupled with valine ethyl ester to give a dipeptide that was subjected to a Sharpless asymmetric dihydroxylation to introduce the diol. The relative configuration at C4 was assigned as S by X-ray crystallography after derivatization as an α-amino-γ-lactone hydrochloride salt. The preparation of the 2-(methylsulfonyl)tryptophan …

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Single-Molecule Detection Of Molecular Beacons Generated From Ldr On Thermoplastic Microfluidic Device For Bioanalysis, Zhiyong Peng Jan 2012

Single-Molecule Detection Of Molecular Beacons Generated From Ldr On Thermoplastic Microfluidic Device For Bioanalysis, Zhiyong Peng

LSU Doctoral Dissertations

Current clinical techniques for nucleic acid detection and analysis often involve PCR, lacking adequate specificity or sensitivity to meet the stringent requirements in certain applications. This research aims to develop an innovative molecular assay and the associated hardware to rapidly signal the presence of certain targets using reporter sequence found in their genome without requiring PCR. This assay coupled the sensitivity of single-pair fluorescence resonance energy transfer (spFRET) with the specificity of ligase detection reaction (LDR) to provide near real-time readout of target biomarkers. Heightened concerns on potential bioterrorism threats, such as rapid dissemination of pathogenic bacteria or viruses into …

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The Effects Of Spatial Confinement And Oxygen Stoichiometry On Complex Metal Oxides, Zhaoliang Liao Jan 2012

The Effects Of Spatial Confinement And Oxygen Stoichiometry On Complex Metal Oxides, Zhaoliang Liao

LSU Doctoral Dissertations

Complex metal oxides, such as transition-metal oxides, appearing with exotic properties and optimal functionalities, present formidable challenges in condensed matter physics, while at the same time, immense opportunities in materials science and engineering. The signature of these materials is the multitude of competing ground states that can be tuned or manipulated by doping, structural modification, strain induction, or the application of external stimulus, such as pressure, electric or magnetic fields, etc. The interest in these materials stems from the richness of their novel properties, the complexity of underlying physics, and the promise of technological applications. Novel phenomena emerge by spatial …

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Nitrogen And Carbon Export To The Gulf Of Mexico By The Atchafalaya River, A Major Distributary Of The Mississippi River, April Elizabeth Bryantmason Jan 2012

Nitrogen And Carbon Export To The Gulf Of Mexico By The Atchafalaya River, A Major Distributary Of The Mississippi River, April Elizabeth Bryantmason

LSU Doctoral Dissertations

Summer hypoxia in the Northern Gulf of Mexico has been attributed to large nutrient inputs, especially nitrate-nitrogen, from the Mississippi-Atchafalaya River system. The 2008 Gulf Hypoxia Action Plan calls for river corridor wetland restoration to reduce nitrate loads, but it is largely unknown how effective riverine wetland systems in the lower Mississippi River (MR) are for nitrate removal. This dissertation research examined nitrate and carbon export from the Atchafalaya River (AR) to: (1) determine nitrate processing by a river swamp basin under varied seasons, (2) investigate nitrate retention and processing in the AR during a major flood event, and (3) …

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Calling For Justice In The Goldfields Of Tanzania, Madoshi H. Makene, Jody Emel, James T. Murphy Jan 2012

Calling For Justice In The Goldfields Of Tanzania, Madoshi H. Makene, Jody Emel, James T. Murphy

Geography

Tanzania is the third largest gold exporter in Africa, thanks in part to the liberalization of the mining sector which started in the early 1990s. Neoliberal mining reforms promised a win-win situation in which government, investors and local host communities would benefit through export earnings, profits, local employment, andcorporate social responsibility initiatives (e.g., the building of schools and clinics). While the rising price of gold and foreign investments in mining activities have delivered on some of these promises, many residents in mining regions have not benefited socioeconomically. Worse still, their communities have unjustly borne the brunt of the environmental, social, …

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Antarctic Surface Melting Dynamics: Enhanced Perspectives From Radar Scatterometer Data, L. D. Trusel, K. E. Frey, S. B. Das Jan 2012

Antarctic Surface Melting Dynamics: Enhanced Perspectives From Radar Scatterometer Data, L. D. Trusel, K. E. Frey, S. B. Das

Geography

Antarctic ice sheet surface melting can regionally influence ice shelf stability, mass balance, and glacier dynamics, in addition to modulating near-surface physical and chemical properties over wide areas. Here, we investigate variability in surface melting from 1999 to 2009 using radar backscatter time series from the SeaWinds scatterometer aboard the QuikSCAT satellite. These daily, continent-wide observations are explored in concert with in situ meteorological records to validate a threshold-based melt detection method. Radar backscatter decreases during melting are significantly correlated with in situ positive degree-days as well as meltwater production determined from energy balance modeling at Neumayer Station, East Antarctica. …

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Hadronic Physics From Extensive Air Showers, Guofeng Yuan Jan 2012

Hadronic Physics From Extensive Air Showers, Guofeng Yuan

LSU Doctoral Dissertations

Although cosmic rays were discovered exactly one century ago, the most fundamental questions about them are still not answered, especially the origin and composition of ultra-high energy cosmic rays (UHECR). The Pierre Auger Observatory (PAO) is constructed with the goal of solving these mysteries. The PAO uses hybrid design and take advantage of both the air fluorescence and surface array technique. Since its debut in 2004, PAO has published several important scientific results.

The most probable candidate for UHECR composition is proton or iron nucleus. The two candidates do show differences in both fluorescence detector (FD) signal and in the …

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What Does The ¹⁴C Method For Estimating Photosynthetic Rates In The Ocean Really Measure?, Shaofeng Pei Jan 2012

What Does The ¹⁴C Method For Estimating Photosynthetic Rates In The Ocean Really Measure?, Shaofeng Pei

LSU Doctoral Dissertations

The 14C method has been used extensively by both limnologists and oceanographers to measure photosynthetic rates in aquatic systems, and the large database of 14C measurements that now exists is the ground truth with which satellite algorithms for estimating marine photosynthetic rates on a basin and global scale have been calibrated. However, disconcerting uncertainties still remain with respect to whether and under what circumstances the 14C method provides an estimate of net or gross photosynthesis, or something in between. My study combined batch and continuous culture studies to clarify this ambiguous issue. The batch culture work with …

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Habitat Use, Movements, And Ecology Of Female Mottled Ducks On The Gulf Coast Of Louisiana And Texas, Bruce Edward Davis Jan 2012

Habitat Use, Movements, And Ecology Of Female Mottled Ducks On The Gulf Coast Of Louisiana And Texas, Bruce Edward Davis

LSU Doctoral Dissertations

Mottled ducks (Anas fulvigula) are the most abundant breeding waterfowl in the coastal marshes of Louisiana and Texas. Mottled ducks are non-migratory and heavily dependent on coastal marsh habitats; they must satisfy all of their annual resource needs from within the Gulf Coast region. Coastal marsh habitats are being rapidly lost or degraded in Louisiana and Texas. The hydrology of many coastal marsh habitats has been altered by anthropogenic activity and natural factors. Parameters related to Mottled Duck habitat use and movements in this altered environment are poorly understood, and managers need information on vital rates of Mottled Ducks in …

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Image Reconstruction Through Polyfiltered Variation Minimization, Michael Hagen Jan 2012

Image Reconstruction Through Polyfiltered Variation Minimization, Michael Hagen

Master's Theses and Doctoral Dissertations

There has been considerable interest in reconstruction of remotely sensed imagery from incomplete frequency measurements for some time now. Given the nature of the collection process, it may be that portions of the spectrum are either missing or corrupted such that one is left with an incomplete representation of the original image. The advances in both the theory and available software for sparse signal reconstruction through function minimization make it an attractive approach for recreating the missing frequency data. It is the aim of this thesis to generalize the reconstruction technique known as Total Variation (TV) minimization from a signal …

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Development Techniques For Android Platform Mobile Device Application, Ivan Njunjic Jan 2012

Development Techniques For Android Platform Mobile Device Application, Ivan Njunjic

Master's Theses and Doctoral Dissertations

This thesis focuses on Android application development techniques needed to implement a mobile application portal that consists of features used at Eastern Michigan University. Since there is not a single source available to developers that explains such techniques, this thesis represents a unique manual for such development. Based on the similarity of features, mainly in terms of data nature and access, five techniques are defined in a step-by-step procedural manner. This is accomplished by outlining the development techniques and presenting them “in action” with coding examples from a fully developed demo application. As a result, the demo application demonstrates functional …

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Design And Analysis Of Cloaked Fluorophores For Rapid Detection And Visualization Of Cancer Cells Containing Nad(P)H:Quinone Oxidoreductase-1, William Silvers Jan 2012

Design And Analysis Of Cloaked Fluorophores For Rapid Detection And Visualization Of Cancer Cells Containing Nad(P)H:Quinone Oxidoreductase-1, William Silvers

LSU Doctoral Dissertations

The development of fluorogenic substrates for real-time tumor cell detection has led to a vastly expanding field for personal oncology. Fluorophores have been studied as appendages to larger scaffolds leading to accumulation of these dyes in tumor cells or their surrounding environment, taking advantage of tumor anatomy. A new class of fluorophores has been developed in which the dye is an active participant in the mechanism of cancer cell detection. These dyes have been conjugated such that their fluorescence has been eliminated or altered and will undergo a change to reveal their fluorescent signal upon activation by a mechanism that …

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Studies Of A Dirhodium Tetraphosphine Catalyst For Hydroformylation And Aldehyde-Water Shift Catalysis, Aaron Rider Barnum Jan 2012

Studies Of A Dirhodium Tetraphosphine Catalyst For Hydroformylation And Aldehyde-Water Shift Catalysis, Aaron Rider Barnum

LSU Doctoral Dissertations

Research into the dirhodium tetraphosphine catalyst precursor [rac-Rh2(nbd)2(et,ph-P4)](BF4)2 shows it is capable of forming a highly active and regioselective hydroformylation catalyst in situ when using an acetone or acetone/water solvent. Hydroformylation experiments (using 1-hexene), FT-IR studies, and acid-base studies were performed to better understand the various complexes of the dirhodium catalyst cycle. These studies lead to the newly proposed catalyst mechanism when performed in an acetone/water solution, using the monocationic [rac-Rh2(H)(µ-CO)2(CO) (et,ph-P4)]+ as the proposed active catalyst complex for hydroformylation. For the conversion of 1-hexene to heptanal, it is capable of performing an initial rate of 30 turnovers per min, …

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