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Full-Text Articles in Physical Sciences and Mathematics

A Method To Measure The Detective Quantum Efficiency Of Radiographic Systems In Clinical Setting, Michael C. Mcdonald Apr 2012

A Method To Measure The Detective Quantum Efficiency Of Radiographic Systems In Clinical Setting, Michael C. Mcdonald

Electronic Thesis and Dissertation Repository

The risks associated with exposure to radiation make it critical that digital imaging systems give the best possible images for a given dose to the patient. The DQE is the most widely accepted measure of performance and dose efficiency for digital radiography systems, however it is not commonly measured in a clinical environment as part of routine quality assurance. The primary reason for this is that the data provided to the user by clinical systems has typically undergone image processing and therefore may have a non-linear characteristic response. This is a problem because the Fourier metrics of the DQE require …


Automation Of The Registration Of Range Plant Images Using Geomagic Studio, Quazi M. Akter Apr 2012

Automation Of The Registration Of Range Plant Images Using Geomagic Studio, Quazi M. Akter

Electronic Thesis and Dissertation Repository

As plant science advances, the quantitative measurement of 3D plant growth has become an essential tool to evaluate the growth performance of genetically modified seeds or plants. In the past, “wet volumes” had been used to quantitatively measure plant growth which result in the destruction of the plants. Other traditional methods like interferometry methods or mechanical methods are also inefficient because they are either invasive or unable to provide sufficient growth information of the plant body. On the other hand, computer vision methods, especially optical and range flow techniques, are non-contact, more accurate, and relatively less expensive. But they require …


Solid-State Nuclear Magnetic Resonance Spectroscopy Of Unreceptive Quadrupolar Nuclei In Inorganic Materials, Andre Sutrisno Apr 2012

Solid-State Nuclear Magnetic Resonance Spectroscopy Of Unreceptive Quadrupolar Nuclei In Inorganic Materials, Andre Sutrisno

Electronic Thesis and Dissertation Repository

Preparation and characterization of inorganic materials is a crucial practice because understanding the relationship between structure and property is important for improving current performance and developing novel materials. Many metal centers in technologically and industrially important materials are unreceptive low-γ quadrupolar nuclei (i.e., possessing low natural abundance, low NMR frequencies and large quadrupole moments) and they usually give rise to very broad NMR resonances and low signal-to-noise ratios, making it difficult to acquire their solid-state NMR spectra. This thesis focuses on the characterization of inorganic materials using solid-state NMR (SSNMR) spectroscopy at very high magnetic field of …


Enhancing Raman And Fluorescence Spectroscopies With Nanosphere Lithography Platforms, Shabila Fayyaz Apr 2012

Enhancing Raman And Fluorescence Spectroscopies With Nanosphere Lithography Platforms, Shabila Fayyaz

Electronic Thesis and Dissertation Repository

Localized surface plasmon resonance (LSPR) is of particular interest to enhance the limit of detection for spectroscopic techniques such as Raman and fluorescence via a surface enhancement from metallic nanostructures. In this study, using nanosphere lithography (NSL) technique, a series of gold nanostructures over glass surfaces are prepared. These nanostructures are used to record the surface enhanced Raman scattering (SERS) spectrum of benzenethiol and azobenzene thiol and the vibrational modes are compared to literature. Once protected with an ultrathin layer of SiO2, the gold nanostructures are investigated using scanning confocal fluorescence microscopy to detect the fluorescence from a …


Hearts And Minds: Examining The Evolution Of The Egyptian Excerebration And Evisceration Traditions Through The Impact Mummy Database, Andrew D. Wade Apr 2012

Hearts And Minds: Examining The Evolution Of The Egyptian Excerebration And Evisceration Traditions Through The Impact Mummy Database, Andrew D. Wade

Electronic Thesis and Dissertation Repository

Egyptian mummification and funerary rituals were a transformative process, making the deceased a pure being; free of disease, injury, and disfigurements, as well as ethical and moral impurities. Consequently, the features of mummification available to specific categories of individuals hold social and ideological significance. This study refutes long-held classical stereotypes, particularly dogmatic class associations; demonstrates the apocryphal nature of universal heart retention; and expands on the purposes of excerebration and evisceration implied by synthetic and radiological analyses.

Features of the embalming traditions, specifically the variable excerebration and evisceration traditions, represented the Egyptian view of death. Fine-grain analyses, through primary imaging …


The Research On The L(2,1)-Labeling Problem From Graph Theoretic And Graph Algorithmic Approaches, Zhendong Shao Apr 2012

The Research On The L(2,1)-Labeling Problem From Graph Theoretic And Graph Algorithmic Approaches, Zhendong Shao

Electronic Thesis and Dissertation Repository

The L(2,1) -labeling problem has been extensively researched on many graph classes. In this thesis, we have also studied the problem on some particular classes of graphs.

In Chapter 2 we present a new general approach to derive upper bounds for L(2,1)-labeling numbers and applied that approach to derive bounds for the four standard graph products.

In Chapter 3 we study the L(2,1)-labeling number of the composition of n graphs.

In Chapter 4 we consider the Cartesian sum of graphs and derive, both, lower and upper bounds for their L(2,1)-labeling number. We use two different approaches to derive the upper …


Synthesis Of Self-Immolative Monomers And Their Applications In Polymeric Materials, Matthew A. Dewit Apr 2012

Synthesis Of Self-Immolative Monomers And Their Applications In Polymeric Materials, Matthew A. Dewit

Electronic Thesis and Dissertation Repository

Self-immolative spacers are a unique class of molecules employed in a variety of applications, particularly in the biomedical field. Most commonly, they are molecules containing two reactive termini with a capping group at one terminus and a substrate of interest at the other. Upon removal of the capping group, the spacer undergoes an intramolecular reaction that results in its removal from the molecule and liberation of the substrate. These spacers have been extensively studied in monomeric form within prodrugs, as well as to form dendrimers that have been used for applications such as signal amplification, molecular logic gates and amplified …


Late Quaternary Histories Of Lakes Huron And Michigan: A Stable Isotope Investigation Of Sediment Cores And Modern Biogenic Carbonates, Rebecca A. Macdonald Apr 2012

Late Quaternary Histories Of Lakes Huron And Michigan: A Stable Isotope Investigation Of Sediment Cores And Modern Biogenic Carbonates, Rebecca A. Macdonald

Electronic Thesis and Dissertation Repository

Late Quaternary histories are investigated here for sediment cores from Lakes Huron and Michigan, using the oxygen- and carbon-isotope compositions of biogenic carbonates and the oxygen- and hydrogen-isotope compositions of porewater. Age models for these cores are based on sedimentological information, and where possible, radiocarbon and pollen dates. The Michigan Basin cores provide a thick record of the late Pleistocene, whereas the Huron Basin cores primarily record Holocene deposition. Taken together, the histories recorded in biogenic carbonates from these sediments provide a clear account of lakewater isotopic changes – and their significance – over much of the history of the …


An Investigation Of Deformation Structures And Their Tectonic Significance Across The Grenville Front Tectonic Zone In The Vicinity Of Sudbury, Ontario, Canada, Changcheng Li Apr 2012

An Investigation Of Deformation Structures And Their Tectonic Significance Across The Grenville Front Tectonic Zone In The Vicinity Of Sudbury, Ontario, Canada, Changcheng Li

Electronic Thesis and Dissertation Repository

The Grenville Front Tectonic Zone (GFTZ) is a polyphase deformation belt in the northwest of the Grenville Province which was shaped in the continent-continent-collision-induced Grenvillian Orogeny.

This thesis focuses on the evolution of deformation fabrics in the GFTZ between the Sudbury Basin and French River in Ontario, Canada. Geological mapping using a new digital mapping system was conducted within this segment of the GFTZ, in its northwest vicinity in the Southern Province, and in its southeast vicinity in the Grenville Province. The new digital mapping system includes a personal digital assistant equipped with an internal GPS and a mobile GIS …


Reconstructing Fire Severity From The Oxygen-Isotope Compositions Of Plant Char, Michael W. Hamilton Apr 2012

Reconstructing Fire Severity From The Oxygen-Isotope Compositions Of Plant Char, Michael W. Hamilton

Electronic Thesis and Dissertation Repository

This study assessed whether variations in the oxygen-isotope compositions of char formed from biomass burning could be related to burning severity. Ground samples of oak (Quercus alba), pine (Pinus resinosa), and grass (Andropogon gerardii) were charred for 5 and 30 minutes at constant temperatures between 200 and 900°C under oxygenated versus anaerobic conditions. Char oxygen-isotope values became progressively depleted of 18O by up to 25.8‰ for wood and 16.5‰ for grass as temperature, duration of burning, and amount of oxygen increased. The primary reason for the decrease in oxygen-isotope values is the loss …


Progress Towards The Total Synthesis Of Amphidinolide C, Nicholas A. Morra Apr 2012

Progress Towards The Total Synthesis Of Amphidinolide C, Nicholas A. Morra

Electronic Thesis and Dissertation Repository

A second generation catalyst for the Mukaiyama oxidative cyclization for the formation of trans-THF rings is described. Co(nmp)2, displays increased stability to the reaction conditions, resulting in lower catalyst loadings, lower reaction temperatures, and significantly higher purity and yields of the products. Three procedures have been developed with this new water-soluble catalyst that greatly simplifies the post-reaction purification, making this procedure the premier method of forming trans-THF rings.

This new catalyst has been applied towards the total synthesis of the potently bioactive macrocycle, Amphidinolide C. Herein we report the successful synthesis of several fragments of the …


Synthesis Of (±)-Quebrachamine, Tetrahydroisoquinocarbazoles, And Progress Towards Biselide A And E, Barbora Morra Apr 2012

Synthesis Of (±)-Quebrachamine, Tetrahydroisoquinocarbazoles, And Progress Towards Biselide A And E, Barbora Morra

Electronic Thesis and Dissertation Repository

A variety of methodologies developed in our research group have inspired the three separate projects reported. First, the total synthesis of (±)-quebrachamine was performed in 13 steps and 17.8% overall yield. Highlights of the synthesis include an efficient preparation of a functionalized indole core via a [3+2] annulation cycloaddition reaction between a functionalized nitrile and donor-acceptor cyclopropane and a photo induced 9-membered ring closure.

Secondly, we have reported the most efficent and highest yielding route to several tetrahydroisoquinocarbazoles, where the core was prepared in six steps from tryptophol in 51% overall yield. This work highlights for the first time the …


Multi-Core Unit Propagation In Functional Languages, Jonathan Alexander Leaver Apr 2012

Multi-Core Unit Propagation In Functional Languages, Jonathan Alexander Leaver

Electronic Thesis and Dissertation Repository

Answer Set Programming is a declarative modeling paradigm enabling specialists in diverse disciplines to describe and solve complicated problems. Growth in high performance computing is driving ever smarter and more scalable parallel answer set solvers. To improve on today's cutting-edge, researchers need to develop increasingly intelligent methods for analysis of a solver's runtime information. Reflecting on the solver's search state typically pauses its progress until the analysis is complete. This work introduces methods from the domain of parallel functional programming and immutable type theory to construct a representation of the search state that is both amenable to introspection and efficiently …


Molecular Dynamics Simulations Of Peptide-Mineral Interactions, Susanna Hug Apr 2012

Molecular Dynamics Simulations Of Peptide-Mineral Interactions, Susanna Hug

Electronic Thesis and Dissertation Repository

We present molecular dynamics (MD) simulations providing information about the mechanisms of biomineralization. We focus on osteopontin-related peptides, which inhibit the growth of calcium oxalate monohydrate (COM) the primary constituent of kidney stones.

First, we performed two ab initio MD simulations: aspartic acid (Asp) and the dimer of aspartic acid and phosphoserine (Asp-pSer) interacting with a fully hydrated COM crystal slab exposing the {100} face. For Asp we found that one of the carboxyl and the amine group both interact with the crystal surface but neither forms a stable contact during the simulation. Asp-pSer interacts preferably with its carboxyl groups …


Scanning Probe Microscopy Studies Of The Properties Of Conducting Polymers, Kevin D. O'Neil Apr 2012

Scanning Probe Microscopy Studies Of The Properties Of Conducting Polymers, Kevin D. O'Neil

Electronic Thesis and Dissertation Repository

Electronically conducting polymers (ECPs) have been growing in interest as important materials for a variety of different applications such as charge storage devices and photovoltaics. However, in all of these applications, the performance of conducting polymers are strongly dependent upon their local properties such as morphology, local conductivity and carrier mobility, local chemical composition, etc. All polymer materials feature a distribution of these parameters and therefore, they are considered heterogeneous. In this work, we use atomic force microscopy (AFM) and its related techniques such as current-sensing AFM (CS-AFM), Kelvin probe force microscopy (KFM) and phase imaging (PI-AFM) to directly investigate …


Magnetic Properties And Defects In Iron Implanted Strontium Titanate Single Crystals And Thin Films, Misha Chavarha Apr 2012

Magnetic Properties And Defects In Iron Implanted Strontium Titanate Single Crystals And Thin Films, Misha Chavarha

Electronic Thesis and Dissertation Repository

Physical vapor deposition was used to grow good quality crystalline stoichiometric SrTiO3 thin films on Si(001) substrate using a systematic approach starting from understanding of kinetics and thermodynamics of the system and finishing with the development of procedure for high quality SrTiO3/Si interface. Growth of optimized SrTiO3 perovskite structure on Si requires careful transformation of a thin interfacial SrSix layer into the initial SrTiO3 lattice cells. The critical aspects of the growth, such as low temperature and low oxidant partial pressure, are explained in details. Crystallinity and stoichiometry of SrTiO3 were verified using powder …


Ozone Measurements And Transport, Mohammed Kedir Osman Feb 2012

Ozone Measurements And Transport, Mohammed Kedir Osman

Electronic Thesis and Dissertation Repository

Ozone intrusions from the stratosphere to the troposphere occur as part of the Brewer-Dobson circulation, but the details of the microphysics of the process are unresolved. This research mainly focuses on near-tropopause regions, and examines stratospheric ozone intrusions into the troposphere across this stable zone. My research objective is to identify the small-scale atmospheric dynamical features responsible for the intrusion of stratospheric ozone into the troposphere, and to determine their relative importance from case to case.

Windprofiler radars, together with frequent ozonesonde launches, have been used to detect stratospheric ozone intrusions. This work has been supplemented by numerical simulation via …


Confidence Intervals For Comparison Of The Squared Multiple Correlation Coefficients Of Non-Nested Models, Li Tan Jr. Feb 2012

Confidence Intervals For Comparison Of The Squared Multiple Correlation Coefficients Of Non-Nested Models, Li Tan Jr.

Electronic Thesis and Dissertation Repository

Multiple linear regression analysis is used widely to evaluate how an outcome or responsevariable is related to a set of predictors. Once a final model is specified, the interpretation of predictors can be achieved by assessing the relative importance of predictors.

A common approach to predictor importance is to compare the increase in squared multiple correlation for a given model when one predictor is added to the increase when another predictor is added to the same model.

This thesis proposes asymmetric confidence-intervals for a difference between two correlated squared multiple correlation coefficients of non-nested models. These new proceduresare developed by …


Hyperpolarized Noble Gas Magnetic Resonance Imaging And Dynamic Spectroscopy For Investigation Of Rat Models Of Lung Inflammation, Matthew S. Fox Feb 2012

Hyperpolarized Noble Gas Magnetic Resonance Imaging And Dynamic Spectroscopy For Investigation Of Rat Models Of Lung Inflammation, Matthew S. Fox

Electronic Thesis and Dissertation Repository

Imaging of the lungs using non-ionizing approaches such as hyperpolarized 3He and 129Xe magnetic resonance imaging (MRI) is a useful tool both for research and clinical applications. This work focused on development of 129Xe MRI techniques to investigate inflammation in rat lungs. A rodent model of inflammation, specifically radiation-induced lung injury (RILI) was developed using a collimated 60Co source. A quantitative MRI technique measuring absolute ventilated lung volume (|VLV|) was performed using 129Xe and 3He. Following a comparison between |VLV| values obtained from rats using the previously established 3He method and those obtained …


Studies Of Aftershock Sequences Of Large Subduction Zone Earthquakes, Armick Ivanian Feb 2012

Studies Of Aftershock Sequences Of Large Subduction Zone Earthquakes, Armick Ivanian

Electronic Thesis and Dissertation Repository

Amongst the different types of earthquakes, it is observed that the mega-thrust earthquakes, which occur in subduction zones, are the most devastating. The aftershock sequences following the mega-thrust earthquakes can also increase the level of seismic hazard, even in remote areas away from the mainshock fault zone. This thesis examines the statistical parameters of aftershock sequences of large subduction zone earthquakes that have occurred in the western and eastern Pacific Ocean. These parameters are vital for seismic hazard assessment of regions located near subduction zones. The results show that, on average, the Gutenberg-Richter exponent—the b-value—is markedly higher in the …


A Geobiological Investigation Of The Mazon Creek Concretions Of Northeastern Illinois, Mechanisms Of Formation And Diagenesis, Andrea S. Fernandes Jan 2012

A Geobiological Investigation Of The Mazon Creek Concretions Of Northeastern Illinois, Mechanisms Of Formation And Diagenesis, Andrea S. Fernandes

Electronic Thesis and Dissertation Repository

Siderite concretions from the mid-Pennsylvanian Francis Creek Shale of the Mazon Creek area, in northeastern Illinois, contain exceptionally preserved soft-tissue fossils. Scanning electron microscopy, energy dispersive spectroscopy, time of flight-secondary ion mass spectrometry and micro-x-ray diffraction on polychaete worm, jellyfish and holothurian samples highlighted detrital clay and quartz grains in siderite cement. The worm and jellyfish are pyritised and surrounded by pyrite halos, whereas the holothurian is preserved as a weathered impression. Specimens possessed either microbial textures or framboidal pyrite, in carbon-enriched zones. The carbon-enriched zones contained organic compounds, indicating that extensive degradation associated with high temperature diagenesis did not …


Effects Of Chemical And Mechanical Weathering Processes On The Degradation Of Plastic Debris On Marine Beaches, David A. Cooper Jan 2012

Effects Of Chemical And Mechanical Weathering Processes On The Degradation Of Plastic Debris On Marine Beaches, David A. Cooper

Electronic Thesis and Dissertation Repository

Plastics are an integral part of everyday life, and the use of plastic products for consumer goods, food packaging, recreational and commercial fishing and medical and sanitary applications continues to increase. The durability, low cost, light weight and hydrophobic nature of plastic make it a desirable material for numerous applications; however, these same characteristics make plastic debris in natural environments a pervasive problem. Increases in plastic use and low economic incentive for recovery, result in accumulation of debris in marine environments. Degradation of plastics through chemical weathering occurs in the open ocean or along shorelines where polymers are exposed to …


Miniaturized Fractionation And Purification Of Analytes Of Interest In Complex Mixtures: Protein Enrichment And Purification With Capillary Electrophoresis And Identification Of Pesticide Chemicals In Bio-Oils, Christina J. Booker Jan 2012

Miniaturized Fractionation And Purification Of Analytes Of Interest In Complex Mixtures: Protein Enrichment And Purification With Capillary Electrophoresis And Identification Of Pesticide Chemicals In Bio-Oils, Christina J. Booker

Electronic Thesis and Dissertation Repository

The ability to isolate and detect an analyte of interest is vital for many different facets of life today, from disease detection to environmental safety. The goal of the method development discussed within this thesis is to isolate and identify unique analytes from complex matrices and to do so in a scaled down approach. Removal of an analyte from a diverse background of molecules is often required for successful detection and determination of analyte properties. As well, many samples are only available at low volumes and at trace levels so miniaturized techniques that only require small sample volumes are designed …


Relationships Between Earthquake Ground Motions And Modified Mercalli Intensity, Andrea Sweny Jan 2012

Relationships Between Earthquake Ground Motions And Modified Mercalli Intensity, Andrea Sweny

Electronic Thesis and Dissertation Repository

With widespread Internet use, web-based earthquake reports are a valuable source of felt intensitydata with broad geographical coverage. Paired with ground motion data, Internet surveys like theUSGS Did You Feel It? (DYFI) website can be used to derive relationships between ground motionparameters and Modified Mercalli Intensity (MMI). These are particularly important for regionswith sparse seismographic coverage where the quality and density of intensity data may be superiorto ground motion data. MMI-ground motion relationships are also needed to infer ground motionsof historical earthquakes.

Using well-documented earthquakes in across North America, we analyze correlations betweenfelt intensity and ground motions, including peak ground …


Syntheses, Hydrogen Bonding, And Metal Coordination Studies Of New Ferrocene Peptide Conjugates, Craig D. Colquhoun Jan 2012

Syntheses, Hydrogen Bonding, And Metal Coordination Studies Of New Ferrocene Peptide Conjugates, Craig D. Colquhoun

Electronic Thesis and Dissertation Repository

The main goal of the research was the synthesis of new ferrocene peptideconjugates, to study the role of hydrogen bonding interactions, and the coordinationproperties of these systems. Ferrocene peptide conjugates have been extensivelystudied as models of protein secondary structures. Of particular interest weredisubstituted ferrocene derivatives such as ferrocene dicarboxylic acid, which have beenshown to be important in the design of peptide mimics. The inter-ring spacing betweentwo cyclopentadienyl rings in ferrocene has shown to be appropriate for forminghydrogen bonds between conjugated peptide chains, which are attached to the twocyclopentadienyl rings. Inter-ring spacing has proven to be of great importance for theformation …