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Articles 631 - 660 of 2906

Full-Text Articles in Physical Sciences and Mathematics

Lithofaces And Sequence Architecture Of The Upper Paradox Formation (Middle Pennsylvanian)In The Subsurface Northern Blanding Subbasin, Paradox Basin, Utah, Geoffrey William Ritter Apr 2018

Lithofaces And Sequence Architecture Of The Upper Paradox Formation (Middle Pennsylvanian)In The Subsurface Northern Blanding Subbasin, Paradox Basin, Utah, Geoffrey William Ritter

Theses and Dissertations

THE PARADOX Basin is a northwest-southeast trending intracratonic basin that formedin southwestern Colorado, southeastern Utah and adjacent parts of Arizona and New Mexicoduring the late Paleozoic Era. During rise of the adjacent Uncompahgre Uplift (Ancestral RockyMountains) the rapidly subsiding basin was filled with over 2000 m of Permo-Pennsylvaniansediments. Stacked depositional sequences accumulated in three roughly parallel facies belts: anortheastern clastic belt (adjacent to uplift), a central salt and black shale belt, and asouthwestern carbonate belt. Over 400 million barrels of oil have been extracted from upperParadox (Desert Creek and Ismay) carbonates in the southern Blanding Subbasin (Greater AnethField) since 1956. …

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Creation And Use Of Software For Analysis Of Kinetic Proteomic Experiments, Bradley C. Naylor Apr 2018

Creation And Use Of Software For Analysis Of Kinetic Proteomic Experiments, Bradley C. Naylor

Theses and Dissertations

In this dissertation, I will review the history and general strategies for performing kinetic proteomics. I will then demonstrate that I have published an open source, user-friendly program for other scientists to use to perform kinetic proteomics data analysis, as well as publishing a novel discovery of key ribosomal subunits being replaced within the lifetime of the ribosome, which was discovered through use of kinetic proteomics. Finally, I will discuss work that is ongoing to improve my software tool for use in human subjects, and work being done to combine kinetic proteomics with other global analysis methods to make novel …

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Development Of A Real-Time Auralization System For Assessment Of Vocal Effort In Virtual-Acoustic Environments, Jennifer Kay Whiting Apr 2018

Development Of A Real-Time Auralization System For Assessment Of Vocal Effort In Virtual-Acoustic Environments, Jennifer Kay Whiting

Theses and Dissertations

This thesis describes the development of the real-time convolution system (RTCS) for a little-studied talker/listener in virtual acoustic environments. We include descriptions of the high-resolution directivity measurements of human speech, the RTCS system components, the measurement and characterization of oral-binaural room impulse responses (OBRIRs) for a variety of acoustic environments, and the compensation filter necessary for its validity. In addition to incorporating the high-resolution directivity measurements, this RTCS improved on that developed by Cabrera et al. [1] through the derivation and inclusion of the compensation filter. Objective measures in the time- and frequency-domains, as well as subjective measures, were developed …

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A Geomorphological Study Of Yardangs In China, The Altiplano/Puna Of Argentina, And Iran As Analogs For Yardangs On Titan, Dustin Shawn Northrup Apr 2018

A Geomorphological Study Of Yardangs In China, The Altiplano/Puna Of Argentina, And Iran As Analogs For Yardangs On Titan, Dustin Shawn Northrup

Theses and Dissertations

Collections of straight, RADAR-bright, linear features, or BLFs, on Saturn's moon Titan are revealed in Cassini SAR (Synthetic Aperture RADAR) images. Most are widely distributed across the northern midlatitudes SAR on SAR swaths T18, T23, T30, T64, and T83 and in swath T56 in the southern midlatitudes. To understand the origin of these features, we compare them with terrestrial yardangs in Dunhuang, China, the Altiplano/Puna of Argentina, and the Lut Desert of Iran and with a similar morphological landform, linear dunes in the Namib Sand Sea, Namibia and on Titan. We apply a statistical classification model developed through random forests, …

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Thin Film Carbon Nanofuses For Permanent Data Storage, Kevin Robert Laughlin Apr 2018

Thin Film Carbon Nanofuses For Permanent Data Storage, Kevin Robert Laughlin

Theses and Dissertations

We have fabricated nanofuses from thin-film, arc-evaporation carbon for use in permanent data storage. Thin film carbon fuses have fewer fabrication barriers and retain the required resistivity and structural stability to work as a data storage medium. Carbon thin films were characterized for their electrical, microstructural, and chemical bonding properties. Annealing the thin-film carbon in an argon environment at 400°C reduced the resistivity from about 4*10-2 Ω cm as deposited down to about 5*10-4 Ω cm, allowing a lower blowing voltage. Nanofuses with widths ranging from 200 nm down to 60 nm were fabricated and tested. They blow …

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Subtraction Games: Range And Strict Periodicity, Bryce Emerson Blackham Apr 2018

Subtraction Games: Range And Strict Periodicity, Bryce Emerson Blackham

Theses and Dissertations

In this paper I introduce some background for subtraction games and explore the Sprague-Grundy functions defined on them. I exhibit some subtraction games where the functions are guaranteed to be strictly periodic. I also exhibit a class of subtraction games which have bounded range, and show there are uncountably many of these.

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A New Family Of Topological Invariants, Nicholas Guy Larsen Apr 2018

A New Family Of Topological Invariants, Nicholas Guy Larsen

Theses and Dissertations

We define an extension of the nth homotopy group which can distinguish a larger class of spaces. (E.g., a converging sequence of disjoint circles and the disjoint union of countably many circles, which have isomorphic fundamental groups, regardless of choice of basepoint.) We do this by introducing a generalization of homotopies, called component-homotopies, and defining the nth extended homotopy group to be the set of component-homotopy classes of maps from compact subsets of (0,1)n into a space, with a concatenation operation. We also introduce a method of tree-adjoinment for "connecting" disconnected metric spaces and show how this method can …

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Progress Toward Synthetically Simplified Natural Anticancer Peptide, David W. Kastner, Steven L. Castle Mar 2018

Progress Toward Synthetically Simplified Natural Anticancer Peptide, David W. Kastner, Steven L. Castle

Library/Life Sciences Undergraduate Poster Competition 2018

Yaku’amide A was isolated in late 2010 from the deep-sea sponge Ceratopsion sp. and exhibits potent inhibitory activity against 39 human cancer cell lines via a potentially novel mode of action. However, the total synthesis requires many steps and produces low yields. In this study, we determined two simpler YA analogues that may retain its anticancer properties and can be synthesized in larger quantities. The analogues replace dehydroisoleucine with either dehydroethylnorvaline or dehydrovaline.

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14-3-3zeta Role In Promoting Survival Of Cells To Facilitate Progression Of Cancer, Katie Pennington, Eranga Roshan, Joshua Andersen, Katherine K. Mccormack Mar 2018

14-3-3zeta Role In Promoting Survival Of Cells To Facilitate Progression Of Cancer, Katie Pennington, Eranga Roshan, Joshua Andersen, Katherine K. Mccormack

Student Works

The regulatory protein 14-3-3z promotes cellular growth and survival, and high expression levels of 14-3-3z are associated with mortality in multiple cancer types. 14-3-3z binds cellular proteins in a phosphorylation-dependent manner to modulate their functions. We have been characterizing the interactome of 14-3-3z which will likely lead to candidates for novel therapies for chemoresistant cancers. Tumor cells must be able to survive in a variety of stresses within the tumor microenvironment, including hypoxia, which occurs when tumors lack adequate blood supply. Previous data from our lab suggested that 14-3-3z promotes the adaptation of tumor cells to hypoxic stress. Our hypothesis …

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Discovery Of Possible Paleotsunami Deposits In Pangandaran And Adipala, Java, Indonesia Using Grain Size, Xrd, And 14C Analyses, Kevin L. Stuart Mar 2018

Discovery Of Possible Paleotsunami Deposits In Pangandaran And Adipala, Java, Indonesia Using Grain Size, Xrd, And 14C Analyses, Kevin L. Stuart

Theses and Dissertations

Grain size, 14C age, and X-ray diffraction (XRD) analyses of sediments indicate possible tsunami deposits on the southern coast of Java near Pangandaran and Adipala. Previous studies that have described known recent and paleotsunami deposits were used for comparison. Fining-upward grain size trends, interbedded sand and mud, sediment composition, and trends in heavy mineral abundances are among the characteristics used for tsunami deposit identification. At Batu Kalde, an archaeological site south of Pangandaran, a layer of aragonitic sand with marine fossils was found atop a layer of archaeological fragments at an elevation of ~2-5 m. It is likely this …

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Lithofacies And Sequence Architecture Of The Upper Desert Creek Sequence (Middle Pennsylvanian, Paradox Formation) In The Greater Aneth Field, Southern Paradox Basin, Utah, Evan R. Gunnell Mar 2018

Lithofacies And Sequence Architecture Of The Upper Desert Creek Sequence (Middle Pennsylvanian, Paradox Formation) In The Greater Aneth Field, Southern Paradox Basin, Utah, Evan R. Gunnell

Theses and Dissertations

The Greater Aneth Buildup (GAB) is comprised of the 3rd-order middle Pennsylvanian (Desmoinesian) Desert Creek sequence of the Paradox Formation. A hierarchy of 4th- and 5th order, carbonate-dominated cycles comprise the Upper Desert Creek (UDC) 4th-order sequence. A SE to NW trending transect line, utilizing core and petrophysical data from six oil and gas wells (from SE to NW wells R-19, Q-16, O-16, J-15, K-430, E-313), revealed deposition of seven carbonate facies within four 5th-order parasequences in the UDC. While each of the seven carbonate facies are present across the transect line, the UDC parasequences are dominated by a shallow-water …

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Paleo-Environmental Interpretations And Weathering Effects Of The Mowry Shale From Geochemical Analysis Of Outcrop Samples In The Western Margin Of The Wind River Basin Near Lander, Wyoming, Trevor Robinson Tuttle Mar 2018

Paleo-Environmental Interpretations And Weathering Effects Of The Mowry Shale From Geochemical Analysis Of Outcrop Samples In The Western Margin Of The Wind River Basin Near Lander, Wyoming, Trevor Robinson Tuttle

Theses and Dissertations

The Cretaceous Mowry Shale is an organic-rich, siliceous marine shale, and as such is a known source rock in the Western United States. Studies have documented that total organic carbon (TOC) in the Wind River Basin, Wyoming increases to the southeast. These studies cover large areas with limited sample sets. In this study, over 250 samples were collected near Lander, Wyoming to address spatial heterogeneity of TOC within the Mowry Shale at a much finer scale than previously examined. Samples were collected along five vertical sections at three localities, and following correlation of the vertical sections, which was strongly aided …

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A Large-Scale Analysis Of How Openssl Is Used In Open-Source Software, Scott Jared Heidbrink Mar 2018

A Large-Scale Analysis Of How Openssl Is Used In Open-Source Software, Scott Jared Heidbrink

Theses and Dissertations

As vulnerabilities become more common the security of applications are coming under increased scrutiny. In regards to Internet security, recent work discovers that many vulnerabilities are caused by TLS library misuse. This misuse is attributed to large and confusing APIs and developer misunderstanding of security generally. Due to these problems there is a desire for simplified TLS libraries and security handling. However, as of yet there is no analysis of how the existing APIs are used, beyond how incorrect usage motivates the need to replace them. We provide an analysis of contemporary usage of OpenSSL across 410 popular secure applications. …

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Contribution Of Bulky <&Alpha>,<&Beta>-Dehydroamino Acids To The Proteolytic Stability Andenhanced Folding Of <&Beta>-Hairpins And Progress Towards The Total Synthesis Of Yaku<'>Amide A, Ankur Jalan Mar 2018

Contribution Of Bulky <&Alpha>,<&Beta>-Dehydroamino Acids To The Proteolytic Stability Andenhanced Folding Of <&Beta>-Hairpins And Progress Towards The Total Synthesis Of Yaku<'>Amide A, Ankur Jalan

Theses and Dissertations

This dissertation primarily covers the impact of bulky ,-dehydroamino acids on the proteolytic stability and enhanced folding of -hairpins. It partly describes the progress towards the total synthesis of yakuamide A, a potent anticancer peptide with an IC50 value of 14 ng/mL against leukemia cells. Proteins and peptides are a very attractive source of potential medicinal agents as they can target various protein“protein interactions that are implicated in several diseases and disorders. The global sales of peptide drugs in 2013 were estimated to be about $28 billion and are constantly rising at an appreciable rate. However, peptide drugs have a …

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Lithofacies And Sequence Architecture Of The Upper Desert Creek Sequence (Middle Pennsylvanian, Paradox Formation) In The Greater Aneth Field, Southern Paradox Basin, Utah, Evan R. Gunnell Mar 2018

Lithofacies And Sequence Architecture Of The Upper Desert Creek Sequence (Middle Pennsylvanian, Paradox Formation) In The Greater Aneth Field, Southern Paradox Basin, Utah, Evan R. Gunnell

Theses and Dissertations

The Greater Aneth Buildup (GAB) is comprised of the 3rd-order middle Pennsylvanian (Desmoinesian) Desert Creek sequence of the Paradox Formation. A hierarchy of 4th- and 5th order, carbonate-dominated cycles comprise the Upper Desert Creek (UDC) 4th-order sequence. A SE to NW trending transect line, utilizing core and petrophysical data from six oil and gas wells (from SE to NW wells R-19, Q-16, O-16, J-15, K-430, E-313), revealed deposition of seven carbonate facies within four 5th-order parasequences in the UDC. While each of the seven carbonate facies are present across the transect line, the UDC parasequences are dominated by a shallow-water …

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Assessing Tsunami Risk In Southwest Java, Indonesia: Paleo-Tsunami Deposits And Inundation Modeling, Han Deng Feb 2018

Assessing Tsunami Risk In Southwest Java, Indonesia: Paleo-Tsunami Deposits And Inundation Modeling, Han Deng

Theses and Dissertations

Samples from 13 different sites along the south coast of West Java yield 7 candidate paleo-tsunami sands, which may represent 4 different paleo-tsunami events. Ages obtained from one deposit may document a tsunami and coastal subsidence from an earthquake in 1,053 AD. The tsunami deposit from this event is preserved in an uplifted marine terrace exposed at Panto Cape, Banten Province. We speculated that the terrace has been uplifted about 4.6 m to the present height of 2 m above sea level, since the 1053 AD event at a rate of 4.8 mm/a. This uplift is strong evidence that strain …

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Assessing Tsunami Risk In Southwest Java, Indonesia: Paleo-Tsunami Deposits And Inundation Modeling, Han Deng Feb 2018

Assessing Tsunami Risk In Southwest Java, Indonesia: Paleo-Tsunami Deposits And Inundation Modeling, Han Deng

Theses and Dissertations

Samples from 13 different sites along the south coast of West Java yield 7 candidate paleo-tsunami sands, which may represent 4 different paleo-tsunami events. Ages obtained from one deposit may document a tsunami and coastal subsidence from an earthquake in 1,053 AD. The tsunami deposit from this event is preserved in an uplifted marine terrace exposed at Panto Cape, Banten Province. We speculated that the terrace has been uplifted about 4.6 m to the present height of 2 m above sea level, since the 1053 AD event at a rate of 4.8 mm/a. This uplift is strong evidence that strain …

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Suggesting Missing Information In Text Documents, Grant Michael Hodgson Jan 2018

Suggesting Missing Information In Text Documents, Grant Michael Hodgson

Theses and Dissertations

A key part of contract drafting involves thinking of issues that have not been addressedand adding language that will address the missing issues. To assist attorneys with this task, we present a pipeline approach for identifying missing information within a contract section. The pipeline takes a contract section as input and includes 1) identifying sections that are similar to the input section from a corpus of contract sections; and 2) identifying and suggesting information from the similar sections that are missing from the input section. By taking advantage of sentence embedding and principal component analysis, this approach suggests sentences that …

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Linear Dune Morphometrics In Titan’S Belet Sand Sea And A Comparison With The Namib Sand Sea, Corbin Robert Lewis Jan 2018

Linear Dune Morphometrics In Titan’S Belet Sand Sea And A Comparison With The Namib Sand Sea, Corbin Robert Lewis

Theses and Dissertations

Despite atmospheric and compositional differences on Titan and Earth, the similarity in the shape and spacing of linear dunes of the Belet Sand Sea of Titan and the Namib Sand Sea of Earth suggests that comparisons will yield a better understanding of the dictating factors of duneforming processes. We present a methodology for the collection of dune width and spacing measurements representative of the Namib and Belet sand seas. 94,304 locations in Belet from Cassini SAR images and 5,563 locations in the Namib from IKONOS images are used for measurements. The average width and spacing of linear dunes in Belet …

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Ion Trajectory Simulations And Design Optimization Of Toroidal Ion Trap Mass Spectrometers, Jessica Marie Higgs Dec 2017

Ion Trajectory Simulations And Design Optimization Of Toroidal Ion Trap Mass Spectrometers, Jessica Marie Higgs

Theses and Dissertations

Ion traps can easily be miniaturized to become portable mass spectrometers. Trapped ions can be ejected by adjusting voltage settings of the radiofrequency (RF) signal applied to the electrodes. Several ion trap designs include the quadrupole ion trap (QIT), cylindrical ion trap (CIT), linear ion trap (LIT), rectilinear ion trap (RIT), toroidal ion trap, and cylindrical toroidal ion trap. Although toroidal ion traps are being used more widely in miniaturized mass spectrometers, there is a lack of fundamental understanding of how the toroidal electric field affects ion motion, and therefore, the ion trap's performance as a mass analyzer. Simulation programs …

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Shadow Patching: Exemplar-Based Shadow Removal, Ryan Sears Hintze Dec 2017

Shadow Patching: Exemplar-Based Shadow Removal, Ryan Sears Hintze

Theses and Dissertations

Shadow removal is an important problem for both artists and algorithms. Previous methods handle some shadows well but, because they rely on the shadowed data, perform poorly in cases with severe degradation. Image-completion algorithms can completely replace severely degraded shadowed regions, and perform well with smaller-scale textures, but often fail to reproduce larger-scale macrostructure that may still be visible in the shadowed region. This paper provides a general framework that leverages degraded (e.g., shadowed) data to guide the image completion process by extending the objective function commonly used in current state-of-the-art image completion energy-minimization methods. This approach achieves realistic shadow …

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Dissolved Organic Carbon And Dissolved Metal Pulses During Snowmelt Runoff In The Upper Provo River Watershed, Utah, Usa, Hannah Nicole Checketts Dec 2017

Dissolved Organic Carbon And Dissolved Metal Pulses During Snowmelt Runoff In The Upper Provo River Watershed, Utah, Usa, Hannah Nicole Checketts

Theses and Dissertations

Snowmelt river systems exhibit seasonal fluxes in water chemistry, potentially affecting the water supply of one-sixth of the worlds population. In this study, we examined water chemistry of the upper Provo River, northern Utah, which supplies water to over two million people along the urban Wasatch Front. Seasonal changes in water chemistry were characterized by analyzing discharge and dissolved organic carbon (DOC) with dissolved trace metal and cation concentrations (La, Pb, Cu, Al, Be, Sr and K) over three consecutive water years 20142016, with intensive sampling during snowmelt runoff. To better understand links between metal movement and DOC, we sampled …

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Capacity Of Human Immunodeficiency Virus Targeting Chimeric Antigen Receptor T Cells To Eliminate Follicular Dendritic Cells Bearing Human Immunodeficiency Virus Immune Complexes, Matthew T. Ollerton Dec 2017

Capacity Of Human Immunodeficiency Virus Targeting Chimeric Antigen Receptor T Cells To Eliminate Follicular Dendritic Cells Bearing Human Immunodeficiency Virus Immune Complexes, Matthew T. Ollerton

Theses and Dissertations

An important obstacle to a functional cure for HIV/AIDS is the persistence of viral reservoirs found throughout the body in various cells and tissues. Reservoirs can be latently infected cells, or in the case of follicular dendritic cells (FDC), non-infected cells that trap infectious virus on their surface through immune complexes (HIV-IC). Although several strategies have been employed to target and eliminate viral reservoirs, they are short-lived and ineffective. In an attempt to provide a long-term approach, chimeric antigen receptor T (CAR-T) cells were designed to eliminate native HIV on FDCs. Although effective at eliminating HIV-infected cells, and halting spreading …

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Dissolved Organic Carbon And Dissolved Metal Pulses During Snowmelt Runoff In The Upper Provo River Watershed, Utah, Usa, Hannah Nicole Checketts Dec 2017

Dissolved Organic Carbon And Dissolved Metal Pulses During Snowmelt Runoff In The Upper Provo River Watershed, Utah, Usa, Hannah Nicole Checketts

Theses and Dissertations

Snowmelt river systems exhibit seasonal fluxes in water chemistry, potentially affecting the water supply of one-sixth of the worlds population. In this study, we examined water chemistry of the upper Provo River, northern Utah, which supplies water to over two million people along the urban Wasatch Front. Seasonal changes in water chemistry were characterized by analyzing discharge and dissolved organic carbon (DOC) with dissolved trace metal and cation concentrations (La, Pb, Cu, Al, Be, Sr and K) over three consecutive water years 2014”2016, with intensive sampling during snowmelt runoff. To better understand links between metal movement and DOC, we sampled …

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Acoustic Intensity Of Narrowband Signals In Free-Field Environments, Kelli Fredrickson Succo Dec 2017

Acoustic Intensity Of Narrowband Signals In Free-Field Environments, Kelli Fredrickson Succo

Theses and Dissertations

The phase and amplitude gradient estimator (PAGE) method has proven successful in improving the accuracy of measured energy quantities over the p-p method, which has traditionally been used, in several applications. One advantage of the PAGE method is the use of phase unwrapping, which allows for increased measurement bandwidth above the spatial Nyquist frequency. However, phase unwrapping works best for broadband sources in free-field environments with high coherence. Narrowband sources often do not have coherent phase information over a sufficient bandwidth for a phase unwrapping algorithm to unwrap properly. In fact, phase unwrapping processing can cause significant error when there …

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Recommender Systems For Family History Source Discovery, Derrick James Brinton Dec 2017

Recommender Systems For Family History Source Discovery, Derrick James Brinton

Theses and Dissertations

As interest in family history research increases, greater numbers of amateurs are participating in genealogy. However, finding sources that provide useful information on individuals in genealogical research is often an overwhelming task, even for experts. Many tools assist genealogists in their work, including many computer-based systems. Prior to this work, recommender systems had not yet been applied to genealogy, though their ability to navigate patterns in large amounts of data holds great promise for the genealogical domain. We create the Family History Source Recommender System to mimic human behavior in locating sources of genealogical information. The recommender system is seeded …

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Evaporated Aluminum Fluoride As A Barrier Layer To Retard Oxidation Of Aluminum Mirrors, Margaret Miles Dec 2017

Evaporated Aluminum Fluoride As A Barrier Layer To Retard Oxidation Of Aluminum Mirrors, Margaret Miles

Theses and Dissertations

The aluminum oxide growth rate for aluminum protected with 2.4 nm of aluminum fluoride has been determined. We show that a 2.4 nm aluminum fluoride layer does not prevent aluminum from oxidation but does significantly retard the oxide growth – decreasing the oxide layer thickness from 1 nm in less than an hour to 0.9 nm over 116 hours. Additionally, the optical constants for aluminum oxide growing under an aluminum fluoride barrier layer have been determined – showing an increase in absorption at high energies for Al2O3 forming at room temperature as compared to highly ordered Al …

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Copper Mineralogy In The Oxide Zone Of The Lone Star Porphyry Copper Deposit, Eastern Arizona, Jeff G. Selck Dec 2017

Copper Mineralogy In The Oxide Zone Of The Lone Star Porphyry Copper Deposit, Eastern Arizona, Jeff G. Selck

Theses and Dissertations

The Lone Star porphyry copper deposit in the Safford District of southeastern Arizona was discovered in the late 1800's but never mined on a large scale. In addition to typical copper oxide species such as chrysocolla, the upper part of the deposit has zones of mineralization in which the chemical assays of core samples have higher amounts of copper than can be visually assigned to the observed copper-bearing minerals. The goal of this study is to identify the Cu-bearing minerals, which is crucial because the efficiency of the extraction processes is strongly dependent upon the mineralogy. Samples from seven cores …

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The Morphology And Uniformity Of Circumstellar Oh/H2O Masers Around Oh/Ir Stars, Derek Sean Felli Dec 2017

The Morphology And Uniformity Of Circumstellar Oh/H2O Masers Around Oh/Ir Stars, Derek Sean Felli

Theses and Dissertations

Even though low mass stars (< 8 solar masses) vastly outnumber high mass stars (< 8 solar masses), the more massive stars drive the chemical evolution of galaxies from which the next generation of stars and planets can form. Understanding mass loss of asymptotic giant branch stars contributes to our understanding of the chemical evolution of the galaxy, stellar populations, and star formation history. Stars with mass < 8 solar masses form planetary nebulae, while those with mass < 8 solar masses go supernova. In both cases, these stars enrich their environments with elements heavier than simple hydrogen and helium molecules. While some general info about how stars die and form planetary nebulae are known, specific details are missing due to a lack of high-resolution observations and analysis of the intermediate stages. For example, we know that mass loss in stars creates morphologically diverse planetary nebulae, but we do not know the uniformity of these processes, and therefore lack detailed models to better predict how spherically symmetric stars form asymmetric nebulae. We have selected a specific group of late-stage stars and observed them at different scales to reveal the uniformity of mass loss through different layers close to the star. This includes observing nearby masers that trace the molecular shell structure around these stars. This study revealed detailed structure that was analyzed for uniformity to place constraints on how the mass loss processes behave in models. These results will feed into our ability to create more detailed models to better predict the chemical evolution of the next generation of stars and planets.

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Quantitative Morphological Classification Of Planetary Craterforms Using Multivariate Methods Of Outline-Based Shape Analysis, Thomas Joseph Slezak Dec 2017

Quantitative Morphological Classification Of Planetary Craterforms Using Multivariate Methods Of Outline-Based Shape Analysis, Thomas Joseph Slezak

Theses and Dissertations

Craters formed by impact and volcanic processes are among the most fundamental planetary landforms. This study examines the morphology of diverse craterforms on Io, the Moon, Mars, and Earth using quantitative, outline-based shape analysis and multivariate statistical methods to evaluate the differences between different types of. Ultimately, this should help establish relationships between the form and origin of craterforms. Developed in the field of geometric morphometrics by paleontological and biological sciences communities, these methods were used for the analysis of the shapes of crater outlines. The shapes of terrestrial ash-flow calderas, terrestrial basaltic shield calderas, martian calderas, Ionian paterae, and …

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