Physical Sciences and Mathematics Commons^™

Evaluation Of Jarosite As A Biosignature: A Comparison Of Biogenic And Synthetic Jarosites, Liane Loiselle

Electronic Thesis and Dissertation Repository

The detection of jarosite (K)Fe₃(SO₄)₂OH₆ on Mars has been interpreted as mineralogical evidence of acid-sulfate aqueous processes, including putative evidence of biological activity. Terrestrial habitats where acidic conditions occur are environments where microbiota thrive and generate biological signatures. A biotic and synthetic jarosite were produced to evaluate the ability and effectiveness of existing analytical methods to identify biosignatures in targeted geological materials. Using a comprehensive suite of microscopic (light microscopy, SEM and TEM), mineralogical (XRD), spectroscopic (IR, LIBS, Mössbauer, UV-Vis-NIR, and Raman) and mass spectrometry (ToF-SIMS) techniques, the two jarosites were found to …

Geography, News Media Discourse, And Water Management: A Case Study Of The Devils Lake Outlet, Daniel J. Bednar

Electronic Thesis and Dissertation Repository

This thesis explores the print news media discourse surrounding the dispute between Manitoba and North Dakota over a flood mitigation plan in Devils Lake North Dakota. In order to do so, critical discourse analysis was applied to news media from a seventeen year period during the dispute. Findings were compared between media sources as well as to pertinent policy documents. The thesis finds that the political arena provided by local newspapers as well as the discourses of scale, confrontation, history, and economics had the largest effect on the dispute’s public face. A total of nine findings within these areas are …

Diatoms In Castor Lake (North-Central Washington, Usa) – Proxies Of Climate And Hydrologic Variation, Kelly D. Hollingshead

Electronic Thesis and Dissertation Repository

This research provides a high temporal resolution (1 sample / 2-3 years) record of hydrologic variation for the last 2,000 years using a lake sediment record from Castor Lake, a closed-basin system in Washington, USA. The core was dated using ¹³⁷Cs, ¹⁴C, and tephrochronology. Approximately 600 diatoms were identified and enumerated in 198 samples from a Castor Lake freeze core and Livingstone-piston core. A diatom-inference model for salinity was applied to reconstruct fossil diatom salinity. Diatom-inferred salinity for the last century tracked Palmer Drought Severity Index, indicating diatom community composition tracks effective moisture and can be used to …

Evolution Of The Late Ordovician Plaesiomyid Brachiopod Lineage In Laurentia, Colin D. Sproat

Electronic Thesis and Dissertation Repository

During the Late Ordovician, a transgression flooded much of Laurentia. The fauna of these intracratonic basins became differentiated from the fauna of the pericratonic shelves and platforms, typically displaying gigantism and coarser shell ornamentation. In this study, 509 specimens from 11 species of the Plaesiomyidae brachiopod family from the Katian and Hirnantian were measured, of which 198 included in principal component analysis to quantify morphological changes over this interval. Three trends were revealed: 1) increasing globosity and dorsal convexity from the early to late Katian, 2) coarser, but fewer ribs on species from the paleoequatorial intracratonic seas compared to species …

Stratigraphy And Sedimentology Of The Late Cretaceous (Coniacian) Muskiki And Marshybank Members, Southern Alberta And Northwestern Montana, Meriem Grifi

Electronic Thesis and Dissertation Repository

A high-resolution allostratigraphic study of the Coniacian Muskiki and Marshybank members of the Wapiabi Formation in southern Alberta revealed a southwest thickening wedge of mudstone-dominated strata that was deposited on a shallow storm-dominated shelf. Well-log correlations and biostratigraphy show that the Muskiki Member forms the bulk of the succession; the Marshybank Member is thin or absent in the subsurface. The lower and middle units of the Muskiki Member display regional subsidence patterns consistent with thrust sheet loading in the Cordillera. The upper unit comprises a linear trough filled by southeastward-accreting clinothems. The northeast boundary of the clinoform package corresponds with …

Investigation Of Hydrothermal Alteration Processes In The Troodos Ophiolite And The Abitibi Greenstone Belt, Tamara P. Sredojevic

Electronic Thesis and Dissertation Repository

Hydrothermal alteration is an important and ubiquitous process between rocks in the Earth’s crust and seawater. To gain more understanding of such processes, two localities are investigated here: the Troodos Ophiolite Complex of Cyprus and the syenitic rocks associated with gold mineralization at the Upper Canada property, Kirkland Lake, Ontario. This thesis reports unique effects of hydrothermal activity. The Troodos Ophiolite samples consist of sheeted diabase dykes, gabbroic and ultramafic rocks in the CY-4 drill hole. The oxygen isotopic signature of these rocks indicates that alteration temperatures increased downhole and channeling of low-temperature fluids occurs at the dyke – gabbro …

Technique Design To Increase In-Situ Electrical Connections In A Cubic Anvil Press, Marie April Burford

Electronic Thesis and Dissertation Repository

An experimental technique designed to increase in-situ electrical connections in a cubic anvil press has been developed. Two encompassing cell designs (extruded gasket and pre-formed gasket) were tested with several electrical barrier methods: PVD coatings, G-10/FR-4 and Canvas Electrical (C. E.) phenolic, Teflon and Al ceramic tubing.

Many variations of techniques were attempted and each (n)^th attempt was founded on the experience from/observation of the results obtained with the (n-1)^thtechnique variation. Eighteen pressure cell configurations were designed and tested. The cells with self-extruded gaskets were unsuccessful due to the destructive nature of the extruding gaskets on the …

Studies Of Microscopic Scale Strains In Nickel Alloys Resulting From Mechanical And Chemical Forces, Jing Chao

Electronic Thesis and Dissertation Repository

The nickel-based Alloy 600, also known as Inconel 600 has been found to be susceptible to stress corrosion cracking (SCC) in high temperature aqueous environments. Despite extensive research, the mechanisms by which this process occurs remain in question. It is known that SCC results from the simultaneous effects of a chemically corrosive environment and a tensile stress. Many studies have been conducted on the microscopic chemical changes associated with SCC. There have been fewer studies of the microscopic stress/strain process. The main objective of this thesis is to use the new x-ray based diffraction technique – polychromatic x-ray microdiffraction (PXM) …

A Conceptual Framework For Measuring The Quality Aspect Of Mobile Learning, Luiz Fernando Capretz, Abdalha Ali, Abdelkader Ouda

Electrical and Computer Engineering Publications

With the continuing growth of mobile phones outpacing that of desktops and laptops, mobile phones are the new personal computer. These devices started becoming increasingly sophisticated and extremely powerful. In addition to making phone calls it have the capabilities to perform variety functions, one of the most important functions using it as a classroom tool. However, mobile phone applications must be designed and developed with respect to different technologies skills, learning capabilities and language proficiency in order to be accepted by wide audiences (e.g., students, instructors). However, there is much work that has been done to measure the quality of …

In-Capillary Reduction And Digestion Of Proteins At Nano-Liter Volume Using Capillary Electrophoresis, Thasneen Naina Nazeema

Electronic Thesis and Dissertation Repository

To analyze the proteins present in biological samples several major steps are involved. One of the crucial steps in proteomics has been sample preparation. Prior to mass spectral analysis proteins containing disulfide bonds must be reduced which is followed by digestion. In this work, a novel way of performing protein reduction and digestion at nano-liter volume using capillary electrophoresis is presented. In this work, zone passing CE technique was utilized to analyze the reduction products in CE. After the successful in-capillary reduction, digestion of protein was also performed. A pH mediated stacking was used to bring the reduced protein and …

Influence Of Quantum Dot Structure On The Optical Properties Of Group Iv Materials Fabricated By Ion Implantation, Eric G. Barbagiovanni

Electronic Thesis and Dissertation Repository

In nanostructures (NSs), to acquire a fundamental understanding of the electronic states by studying the optical properties is inherently complicated. A widely used simplification to this problem comes about by developing a model for a small scale representation of types of NSs and applying it to a hierarchy of fabrication methods. However, this methodology fails to account for structural differences incurred by the fabrication method that lead to differences in the optical properties. Proper modelling is realized by first considering the proper range of experimental parameters individually as inputs to a theoretical model and applying the correct parameters to the …

Fundamental Studies And Bioanalytical Applications Of Nanostructured-Initiator Mass Spectrometry (Nims), Jin Li

Electronic Thesis and Dissertation Repository

Nanostructured-Initiator Mass Spectrometry (NIMS), which uses ‘initiator’ molecules trapped within a nanostructured material to assist the release and ionization of intact molecules adsorbed on that material's surface upon laser or ion irradiation, is a new soft desorption/ ionization technique with several positive attributes including extraordinarily high detection sensitivities, relatively simple sample preparation protocols, and can be initiated using photon or ion irradiation sources. As result NIMS has a great deal of potential for the ready detection of small molecules from complex biofluids including metabolites, and for tissue imaging.

In the thesis, a variety of nanostructured materials including porous silicon (pSi), …

Examining Atmospheric Dust Deposition And Its Effects On Alpine Lakes In The Uinta Mountains, Utah, Oliver J. Squire

Electronic Thesis and Dissertation Repository

The composition and effects of atmospheric dust on remote alpine lakes were investigated using geological and paleolimnolgical techniques. Short cores (< 50 cm long) were retrieved from five lakes on the eastern side of the Uinta Mountains, Utah. Sediment core chronologies are based on 210 Pb and 14C dates. Dust and lake sediment core samples were analyzed for their particle size distribution, mineralogy, and chemistry. Dust was fine grained (< 10 μm) and was enriched (i.e., 50X greater concentrations) in 31 major, minor and trace elements relative to local bedrock material. In lake sediments, changes in the concentrations of key dust elements were recorded beginning in ~ AD 1900. Elements that increased in all five lakes included metals (Bi, Pb, Sb, Sn) and the nutrient P. The metals Cu and Cd also increased in four lakes. These changes are coincident with European settlement, the onset of mining, and the intensification of agriculture. The findings of this thesis show that atmospheric deposition in the Uinta Mountains is unique in composition relative to the last several hundred years. Percentage organics also increased during this period indicating increased productivity. Cladocera community composition recorded changes potentially caused by variations in atmospheric deposition of Ca in this region, although results were inconclusive.

Interactive Augmented Reality As A Support Tool For Parkinson’S Disease Rehabilitation Programs, Andrés Ayala García

Electronic Thesis and Dissertation Repository

In this thesis, an augmented reality system is proposed as an alternative to create multiple interactive virtual environments that might later be used in Parkinson’s Disease rehabilitation programs. The main objective of this thesis is to develop a Wearable Tangible Augmented Reality Environment focused on providing the sense of presence required to effectively immerse patients so that they are able to perform different tasks in context–specific scenarios. By using our system, patients are able to freely navigate different virtual environments. Moreover, by segmenting and then overlaying users’ hands and objects of interest above the 3D environment, patients have the ability …

Topics In Field Theory, Alexander Patrushev

Electronic Thesis and Dissertation Repository

This thesis consists of different projects in classical and quantum field theory on a curved background which are connected by a common usage of theoretical ideas as well as cal- culation techniques. The introduction clarifies such connections. In the second chapter we apply the Dirac constraint formalism to the second and first order 1 + 1 dimensional gravitational action coupled to a scalar field. The third chapter is devoted to a calculation of the one loop effective action for a spinor field coupled to a constant background chiral vector field. In the fourth chapter we find a new expression for …

Approximate Methods For Dynamic Portfolio Allocation Under Transaction Costs, Nabeel Butt

Electronic Thesis and Dissertation Repository

The thesis provides robust and efficient lattice based algorithms for solving dynamic portfolio allocation problems under transaction costs. The early part of the thesis concentrates upon developing a toolbox based on multinomial trees. The multinomial trees are shown to provide a reasonable approximation for most popular transaction cost models in the academic literature. The tool, once forged, is implemented in the powerful Mathematica based parallel computing environment. In the second part of the thesis we provide applications of our framework to real world problems. We show re-balancing portfolios is more valuable in an investment environment where the growth and volatility …

Analysis Of Adp-Ribosylation And Protein Sample Preparation By Capillary Electrophoresis, Ming Huang

Electronic Thesis and Dissertation Repository

ADP-ribosylation is one of many biologically important protein post-translational modifications (PTMs) that received considerable research interest in the past decade. The first part of this work presents the analysis of ADP-ribosylation, with special focus on the catalytic domain of an enzyme ARTD-10. The application of capillary electrophoresis (CE) is proposed in this work to separate the in vitro enzymatic mono-ADP-ribosylated ARTD-10 catalytic domain and its unmodified form. Another exciting aspect of CE application with growing interest is the sample preparation. The effectiveness and efficiency for in-vial reaction, in-capillary mixed reaction and on-capillary-tip reaction by performing methyl esterification on phophopeptides were …

An Investigation Into Earthquake Ground Motion Characteristics In Japan With Emphasis On The 2011 M9.0 Tohoku Earthquake, Hadi Ghofrani

Electronic Thesis and Dissertation Repository

In this integrated study, ground-motion characteristics of one of the most devastating earthquakes in history, the 11^th March 2011 Tohoku-oki earthquake (moment magnitude (M) 9.0), are investigated. The investigation centers on developing empirical and simulated-based ground-motion prediction models for this earthquake. These models allow prediction of expected ground motions from large interface (mega-thrust) earthquakes and estimation of their variability due to variability in input parameters, specifically source characteristics (e.g. slip distributions), propagation path, and site effects.

This research work can be divided into two main parts. In the first part, the influence of regional geologic structure, in …

Investigations Of Zeolite Growth By Atomic Force Microscopy (Afm), Donghan Chen

Electronic Thesis and Dissertation Repository

Zeolites are microporous materials that have been used extensively in various fields. A better understanding on their crystallization process is important for their investigations. Atomic force microscopy (AFM) is a powerful tool for studying the growing traces on the crystal surface, providing information regarding the relation between surface events and framework structure. This thesis mainly focuses on the surface investigation of several zeolites and microporous materials. ZSM-11 single crystals were synthesized under hydrothermal conditions, and their crystallization process was monitored by AFM, PXRD, SEM, and SSNMR. SAPO-34 prepared under both HTS and DGC conditions showed morphological differences that are related …

Modeling Sequential Event Times Using Family Data, Balakumar Swaminathan

Electronic Thesis and Dissertation Repository

In genetic epidemiology, families harboring certain genetic mutations are predisposed to successive cancers in their lifetime. This thesis aims to provide reliable estimates of relative risk and age-dependent cumulative risks (penetrance) associated with the mutated gene for successive cancers. We develop a statistical framework for modeling sequential event times arising from family data. A shared frailty model is employed to incorporate the dependence between the two event times. Because families are ascertained through non-random sampling, an ascertainment-corrected retrospective likelihood approach is proposed to account for the non-ignorable sampling design. Simulation studies demonstrate that our proposed method provides unbiased and reliable …

Ionothermal Synthesis Of High Silica Zeolites In Deep Eutectic Solvents (Des), Zheng Sonia Lin

Electronic Thesis and Dissertation Repository

Phase-pure high silica zeolites have been synthesized using different deep eutectic solvents for the first time. ZSM-5 was made in tetrapropylammonium bromide/pentaerythritol. The reaction is affected by the amounts of seeding, water content, and organic structure-directing agent (SDA). Sodalite and ZSM-39 were prepared in tetramethylammonium chloride (TMACl)/1, 6-hexanediol by using the mineralizing agents NaOH and NH₄F, respectively. In urea/choline chloride, ZSM-5, Beta, ZSM-39, and ZSM-11 were made by using different organic SDAs in the presence of fluoride. The reaction temperature and the choice of organic SDA affect the type of structures being produced.

The crystallization of ZSM-39 in …

Late Archean Oceans: A Laboratory Model Of Oxygen Oases, Maija J. Raudsepp

Electronic Thesis and Dissertation Repository

A cyanobacterial mat, including associated aerobic and anaerobic heterotrophs, was grown in an airtight chamber to simulate the formation of an oxygen oasis in two different Archean-like environments. In the first experiment, methane added to the ecosystem was rapidly oxidized and then O_2(g) increased to 10%. Photosynthesis resulted in a pH of 9.5 and the precipitation of magnesium-manganese carbonates within the mat. In the second experiment, daily additions of ferrous iron were rapidly oxidized, resulting in ferric hydroxide encrusted mat. The growth of cyanobacteria and iron reducing bacteria resulted in an active redox cycle between ferrous and ferric iron. …

Molecular Dynamics Studies Of Water Flow In Carbon Nanotubes, Alexander D. Marshall

Electronic Thesis and Dissertation Repository

We present classical molecular dynamics (MD) simulations providing insight into the behaviour of water. We focus on confined water, the properties of which are often significantly different from the properties of bulk water.

First, we performed several simulations investigating the handling of long-range interactions in GROMACS [1], a MD simulation package. Selection of simulation protocols such as handling of long-range interactions is often overlooked, sometimes to the significant detriment of the final result [2, 3, 4]. Ensuring that the chosen simulation protocols are appropriate is a critical step in computer simulation.

Second, we performed MD simulations where water flowed between …

Scanning Electrochemical Microscopy Studies Of Nickel Surfaces And T24 Single Live Cells, Yu Sun

Electronic Thesis and Dissertation Repository

Scanning electrochemical microscopy offers a good insight into nickel surface analysis and human bladder cancer cell studies.

The surface microstructures are related with chemical reactivity by superimposing SECM, SEM and Tof-SIMS images together. Depth scans were exploited for studying chemical reactivity quantitatively by comparison with COMSOL simulation results. Simulation models are described.

Extracellular reactive oxygen species are detected by SECM. Quantitative results were demonstrated by simulation, and concentrations of H₂O₂ and O₂ were acquired. The interaction between cancer cells and vitamin C was investigated. The switch-type behaviour of vitamin C on the PMA-induced ROS burst of …

Assessing The Potential Health Risk Of Cyanobacteria Harmful Algal Blooms And Cyanotoxins In Lake Naivasha, Kenya, Melissa H. Raffoul

Electronic Thesis and Dissertation Repository

Cyanobacteria harmful algal blooms (cyanoHABs) pose a threat to water quality and human health. The Lake Naivasha, Kenya community expressed concern about these events which prompted this study of influences, characteristics and health impacts of cyanoHABs. While eutrophication of Lake Naivasha was caused by years of nutrient loading from agricultural activities, land use changes and improper sewage treatment, results suggest that lake-wide cyanoHAB formation was controlled by shifts from drought to flood conditions, followed by relative stability. Particulate concentrations of the liver toxin microcystin were less than provisional guidelines; however, our limited knowledge on long-term microcystin impacts is limited and …

A Convexity Theorem For Symplectomorphism Groups, Seyed Mehdi Mousavi

Electronic Thesis and Dissertation Repository

In this thesis we study the existence of an infinite-dimensional analog of maximal torus in the symplectomorphism groups of toric manifolds. We also prove an infinite-dimensional version of Schur-Horn-Kostant convexity theorem. These results are extensions of the results of Bao-Raiu, Elhadrami, Bloch-Flachka-Ratiu and Bloch-El Hadrami-Flaschka-Raiu.

A New Web Search Engine With Learning Hierarchy, Da Kuang

Electronic Thesis and Dissertation Repository

Most of the existing web search engines (such as Google and Bing) are in the form of keyword-based search. Typically, after the user issues a query with the keywords, the search engine will return a flat list of results. When the query issued by the user is related to a topic, only the keyword matching may not accurately retrieve the whole set of webpages in that topic. On the other hand, there exists another type of search system, particularly in e-Commerce web- sites, where the user can search in the categories of different faceted hierarchies (e.g., product types and price …

Generating Log File Analyzers, Ilse Leal Aulenbacher

Electronic Thesis and Dissertation Repository

Software testing is a crucial part of the software development process, because it helps developers ensure that the software works correctly and according to stakehold- ers’ requirements and specifications. Faulty or problematic software can cause huge financial losses. Automation of testing tasks can have a positive impact on software development, by reducing costs and minimizing human error. Software testing can be divided into three tasks: choosing test cases, running test cases on the software under test (SUT) and evaluating the test results. To evaluate test results, testers need to examine the output of the SUT to determine if it performed …

Preoperative Planning Of Robotics-Assisted Minimally Invasive Cardiac Surgery Under Uncertainty, Hamidreza Azimian

Electronic Thesis and Dissertation Repository

In this thesis, a computational framework for patient-specific preoperative planning of Robotics-Assisted Minimally Invasive Cardiac Surgery (RAMICS) is developed. It is expected that preoperative planning of RAMICS will improve the rate of success by considering robot kinematics, patient-specific thoracic anatomy, and procedure-specific intraoperative conditions. Given the significant anatomical features localized in the preoperative computed tomography images of a patient's thorax, port locations and robot orientations (with respect to the patient's body coordinate frame) are determined to optimize characteristics such as dexterity, reachability, tool approach angles and maneuverability. In this thesis, two approaches for preoperative planning of RAMICS are proposed that …

Synthesis Of Silicide Nanomaterials Using Chemical Vapour Deposition Method, Hamid Norouzi Banis

Electronic Thesis and Dissertation Repository

Recent research has evidenced that nanotechnology may bring about a material revolution which sweeps through different scientific fields and leads to dramatic changes in the use of natural resources and our everyday life. Compared to their bulk counterparts, the nanomaterials may exhibit significantly improved physical properties by shrinking their size to nanometer scale. Metal silicide are distinguished by their features of combining advantages of both metals and semiconductors which promises superior performance various fields. Despite the progress in the synthesis methods of nanomaterials, it still remains a big challenge in controlled synthesis of 1D silicide nanostructures due to the difficulties …