Physical Sciences and Mathematics Commons^™

Choosing A Repository Platform: Open Source Vs. Hosted Solutions, Hillary Corbett, Jimmy Ghaphery, Lauren Work, Sam Byrd

VCU Libraries Faculty and Staff Publications

Discusses selection of a locally hosted, open-source system (DSpace/Fedora) versus a cloud-hosted, proprietary system (Digital Commons), it is important to note that these examples are merely illustrative. Libraries have a range of choices for repository software that includes open source and proprietary in any number of support environments, and exemplary repositories are flourishing on a variety of systems, both open source and proprietary. This chapter focuses on the differences between proprietary and open-source solutions, but also demonstrates how and why libraries choose a repository system. In writing about this process, we realized that it was important to acknowledge that there …

Finding The Cutpoint Of A Continuous Covariate In A Parametric Survival Analysis Model, Kabita Joshi

Theses and Dissertations

In many clinical studies, continuous variables such as age, blood pressure and cholesterol are measured and analyzed. Often clinicians prefer to categorize these continuous variables into different groups, such as low and high risk groups. The goal of this work is to find the cutpoint of a continuous variable where the transition occurs from low to high risk group. Different methods have been published in literature to find such a cutpoint. We extended the methods of Contal and O’Quigley (1999) which was based on the log-rank test and the methods of Klein and Wu (2004) which was based on the …

Influence Of Perkinsus Marinus Infection And Oyster Health On Levels Of Human-Pathogenic Vibrios In Oysters, Lydia M. Bienlien

Dissertations, Theses, and Masters Projects

The eastern oyster Crassostrea virginica is an ecologically and commercially important species whose natural populations have been devastated by overharvesting, habitat destruction, and disease, but the rapid growth of oyster aquaculture has shown potential to restore the economic significance of this species. A key threat to the growth and sustainability of oyster aquaculture is the association of human-pathogenic Vibrio bacteria with product marketed for raw consumption. Two Vibrio species, Vibrio vulnificus and Vibrio parahaemolyticus, are the causes of the highest rates of seafood consumption-related mortality and gastrointestinal illness, respectively. Identification of the factors influencing V. vulnificus and V. parahaemolyticus prevalence …

The Development Of Bicyclic Peptide Library Scaffolds And The Discovery Of Biostable Ligands Using Mrna Display, David E. Hacker

Theses and Dissertations

Peptides are a promising class of therapeutic candidates due to their high specificity and affinity for cellular protein targets. However, peptides are susceptible to protease degradation and are typically not cell-permeable. In efforts to design more effective peptide drug discovery systems, investigators have discovered that incorporation of non-canonical amino acids (ncAAs) and macrocyclization overcome these limitations, making peptides more drug-like.

In this work, we exploit the promiscuity of wild-type aminoacyl-tRNA synthetases (aaRSs) to ‘mischarge’ ncAAs onto tRNA and ribosomally incorporate them into peptides using a cell-free translation system. We have demonstrated the ability to incorporate five ncAAs into a single …

Gis Data: City Of Chesapeake, Virginia Tidal Marsh Inventory, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, David Stanhope, Karen Duhring, Kallie Brown, Jessica Hendricks, David Weiss, Carl Hershner

Data

The 2016 Tidal Marsh Inventory update for City of Chesapeake, Virginia was generated using on-screen digitizing techniques in the most recent version of ArcGIS® - ArcMap while viewing conditions observed in the most recent imagery from the Virginia Base Mapping Program (VBMP). Dominant plant community types were primarily determined during field surveys from shallow-draft boats moving along the shoreline. Land-based surveys were performed in some locations. One shapefile is developed that portrays tidal marsh areas represented as polygons. A metadata file accompanies the shapefile to define attribute accuracy, data development, and any use restrictions that pertain to the data.

Are Long Tide Gauge Records In The Wrong Place To Measure Global Mean Sea Level Rise?, P. R. Thompson, B. D. Hamlington, F. W. Landerer, S. Adhikari

CCPO Publications

Ocean dynamics, land motion, and changes in Earth's gravitational and rotational fields cause local sea level change to deviate from the rate of global mean sea level rise. Here we use observations and simulations of spatial structure in sea level change to estimate the likelihood that these processes cause sea level trends in the longest and highest-quality tide gauge records to be systematically biased relative to the true global mean rate. The analyzed records have an average twentieth century rate of approximately 1.6 mm/yr, but based on the locations of these gauges, we show that the simple average underestimates the …

Simulation Of Nuclear Fusion Using A One Dimensional Particle In Cell Method, Steven T. Margell

Cal Poly Humboldt theses and projects

In this thesis several novel techniques are developed to simulate fusion events in an isotropic, electrostatic three-dimensional Deuterium-Tritium plasma. These techniques allow us to accurately predict three-dimensional collision events with a one-dimensional model while simultaneously reducing compute time via a nearest neighbor algorithm. Furthermore, a fusion model based on first principles is developed that yields an average fusion reactivity which correlates well with empirical results.

Experimental Apparatus For Quantum Pumping With A Bose-Einstein Condensate., Megan K. Ivory

Dissertations, Theses, and Masters Projects

No abstract provided.

The Tornado That Struck Embry-Riddle Aeronautical University On Christmas Day, 2006: Lessons Learned From A Near-Miss, John M. Lanicci

Journal of Aviation/Aerospace Education & Research

An F2 tornado that touched down in Daytona Beach on Christmas Day afternoon caused over $50 million of damage to the Embry-Riddle Aeronautical University campus and nearby neighborhoods. The tornado was part of a severe-weather outbreak over Florida, Georgia, and South Carolina that began during the overnight hours of 25 December 2006. Examination of surface and upper-level meteorological charts and vertical soundings on the morning of 25 December showed stability and wind-shear conditions favorable for tornadic thunderstorms over this region. The evolution of the squall line that moved through east-central Florida, and the parent thunderstorm that produced the tornado was …

Investigation Of Neural And Epithelial Cadherin Monomer Properties Using A Molecular Dynamics Approach, Lianyi Fan

Electronic Theses and Dissertations

Neural and epithelial cadherin are adhesion proteins intensely studied by our lab. Although the sequence, structure, and conformation are similar for the two cadherins, there are several physical properties that differ: dimerization affinity, dimerization kinetics, intermediate structure, and critical residues for dimerization. In the presence of calcium, cadherins are in equilibrium between monomeric and dimeric states, and the scope of this thesis focuses on monomeric cadherin. These molecular dynamics evaluations are based on the testing of specific hypotheses regarding the intramolecular interactions of neural and epithelial cadherin. We particularly focus on interactions involving critical residues at the N-terminus of the …

Synthesis And Characterization Of Anhydrous Proton Conducting Polymer Electrolytes For Fuel Cell Applications, Buddika Mayomi Liyanage

Electronic Theses and Dissertations

Anhydrous H+ ion conducting and high temperature capability of polymer electrolytes are being investigated for use in applications such as batteries, fuel cells, electro chromic windows and light emitting devices. Fuel cells are efficient electrochemical energy conversion devices; they can generate greener energy from chemical fuels. The polymer electrolyte membrane is heart of most fuel cell designs separating the oxidant and fuel chambers and providing the medium to conduct H+ ions between the anode and the cathode. Our goal is to understand the molecular level details of anhydrous H+ conductivity through the synthesis and characterization of polymer electrolytes based on …

Slip-Jump Model For Carbon Combustion Synthesis Of Complex Oxide Nanoparticles, A. A. Markov, Mkhitar A. Hobosyan, Karen S. Martirosyan

Physics and Astronomy Faculty Publications and Presentations

Carbon Combustion Synthesis of Oxides (CCSO) is a promising method to produce submicron- and nano- sized complex oxides. The CCSO was successfully utilized for producing several complex oxides, a complete theoretical model including the sample porosity, fl ow parameters and reaction energetics is needed to predict the combustion parameters for CCSO. In this work, we studied the ignition temperature and combustion wave axial temperature distribution, activation energy, combustion heat and thermal losses for a typical CCSO synthesis for cylindrical samples of Ni-Zn ferrites with high (>85%) porosity. We developed a two level combustion model of chemically active nano-dispersed mixture, …

A New Right Tailed Test Of The Ratio Of Variances, Elizabeth Rochelle Lesser

UNF Graduate Theses and Dissertations

It is important to be able to compare variances efficiently and accurately regardless of the parent populations. This study proposes a new right tailed test for the ratio of two variances using the Edgeworth’s expansion. To study the Type I error rate and Power performance, simulation was performed on the new test with various combinations of symmetric and skewed distributions. It is found to have more controlled Type I error rates than the existing tests. Additionally, it also has sufficient power. Therefore, the newly derived test provides a good robust alternative to the already existing methods.

Green Remediation Of Acid Mine Drainage (Amd)-Impacted Soil And Water, Abhishek Roychowdhury

Theses, Dissertations and Culminating Projects

Although mining industries such as coal and minerals generate revenue, they are responsible for a number of negative environmental consequences, and the production of acid mine drainage (AMD) and acid sulfate soil are the most concerning among them. Current AMD management practices are expensive, ineffective, or unsustainable. This study evaluated the potential of a cost-effective and environment-friendly “green” technology in treating AMD-impacted water and soil that utilizes the metal-binding and acid-neutralizing capacity of an industrial by-product, namely drinking-water treatment residuals (WTRs) and the extensive root system of a metal hyper-accumulating, fastgrowing, non-invasive, high biomass perennial grass, vetiver (Chrysopopgon zizanioides …

Challenging The Efficient Market Hypothesis With Dynamically Trained Artificial Neural Networks, Kevin M. Harper

UNF Graduate Theses and Dissertations

A review of the literature applying Multilayer Perceptron (MLP) based Artificial Neural Networks (ANNs) to market forecasting leads to three observations: 1) It is clear that simple ANNs, like other nonlinear machine learning techniques, are capable of approximating general market trends 2) It is not clear to what extent such forecasted trends are reliably exploitable in terms of profits obtained via trading activity 3) Most research with ANNs reporting profitable trading activity relies on ANN models trained over one fixed interval which is then tested on a separate out-of-sample fixed interval, and it is not clear to what extent these …

A Saddlepoint Approximation To Left-Tailed Hypothesis Tests Of Variance For Non-Normal Populations, Tyler L. Grimes

UNF Graduate Theses and Dissertations

When the variance of a single population needs to be assessed, the well-known chi-squared test of variance is often used but relies heavily on its normality assumption. For non-normal populations, few alternative tests have been developed to conduct left tailed hypothesis tests of variance. This thesis outlines a method for generating new test statistics using a saddlepoint approximation. Several novel test statistics are proposed. The type-I error rates and power of each test are evaluated using a Monte Carlo simulation study. One of the proposed test statistics, R_gamma2, controls type-I error rates better than existing tests, while having comparable power. …

Towards A New Gis Maturity Model: An Organizational Usage Perspective, Omer Abdulaziz Alrwais

CGU Theses & Dissertations

The first condition required for an Information Technology (IT) system to produce value is that it be used by its designated target group of users. Despite the prevalence of “system use” in IS literature, it has been often limited to the individual level. The organizational perspective is rarely considered. This dissertation focuses on system usage in the GIS domain through an organizational lens. GIS is a technology with the potential to transform government by enhancing business processes and providing a platform to manage spatial and non-spatial data, which is expected to result in better decision-making. However, little is known about …

Towards Theory And Applications Of Generalized Categories To Areas Of Type Theory And Categorical Logic, Lucius Traylor Schoenbaum

LSU Doctoral Dissertations

Motivated by potential applications to theoretical computer science, in particular those areas where the Curry-Howard correspondence plays an important role, as well as by the ongoing search in pure mathematics for feasible approaches to higher category theory, we undertake a detailed study of a new mathematical abstraction, the generalized category. It is a partially defined monoid equipped with endomorphism maps defining sources and targets on arbitrary elements, possibly allowing a proximal behavior with respect to composition. We first present a formal introduction to the theory of generalized categories. We describe functors, equivalences, natural transformations, adjoints, and limits in the generalized …

Studies Of The Properties Of Designed Nanoparticles Using Atomic Force Microscopy, Steve Matthew Deese

LSU Doctoral Dissertations

The purpose of the research in this dissertation was to elucidate the intrinsic properties of how nanoparticles are different from bulk materials. This was done by mechanical and electronic studies of the properties of designed nanoparticles using advanced modes of atomic force microscopy. Information relating to the work functions, contact potential difference, Young’s Moduli, elasticity, and viscoelasticity can be investigated using state-of-the-art atomic force microscope (AFM) experiments. Subsurface imaging of polystyrene encapsulated cobalt nanoparticles was achieved for the first time using Force Modulation Microscopy (FMM) in conjunction with contact mode AFM. Previously prepared sample of polystyrene coated cobalt nanoparticles were …

Robotics In The Classroom: The Effectiveness Of Robotics Based Curriculum In Stem Education, Mark Nall

Graduate Research Papers

Students learn best when they are engaged and are able to interact with their environment. They can build their own definition of concepts and themes, which are more meaningful because they are related to their own experiences and memories (Kolb, 1984). Simply put it all comes down to constructivism, which means a person builds knowledge and meaning from interactions between their experiences and ideas (the environment they work/play in and the people and objects they interact with). The purpose of this study is to find out how a middle school and high school constructivist robotics curriculum impacts students’ conceptual understanding …

A Trace Metal Content Database Of Cave Sediments Of Midcontinent U.S.A., Matthew Dale Smith

MSU Graduate Theses

The midcontinent of the United States has thousands of documented caves. These caves contain cave sediments, which are the accumulation of biological, geological, and anthropological debris. At this time there is no known database for trace metals of cave sediments of the midcontinent United States. Considering that caves host a wide variety of life, it is important to create a database to examine potential effects of trace metals on cave systems. In order to develop this baseline, 14 caves were sampled from across the midcontinent. Caves were selected based on geologic and hydrologic attributes. The sediments were analyzed for the …

Land Use And Land Cover Classification And Change Detection Using Naip Imagery From 2009 To 2014: Table Rock Lake Region, Missouri, Dexuan Sha Sha

MSU Graduate Theses

Land use and land cover (LULC) of Table Rock Lake (TRL) region has changed over the last half century after the construction of Table Rock Dam in 1959. This study uses one meter spatial resolution imagery to classify and detect the change of LULC of three typical waterside TRL regions. The main objectives are to provide an efficient and reliable classification workflow for regional level NAIP aerial imagery and identify the dynamic patterns for study areas. Seven class types are extracted by optimal classification results from year 2009, 2010, 2012 and 2014 of Table Rock Village, Kimberling City and Indian …

A Multivariate Nonlinear Mixed Effects Model For Longitudinal Image Analysis: Application To Amyloid Imaging, Murat Bilgel, Jerry L. Prince, Dean F. Wong, Susan M. Resnick, Bruno M. Jedynak

Mathematics and Statistics Faculty Publications and Presentations

It is important to characterize the temporal trajectories of disease-related biomarkers in order to monitor progression and identify potential points of intervention. These are especially important for neurodegenerative diseases, as therapeutic intervention is most likely to be effective in the preclinical disease stages prior to significant neuronal damage. Neuroimaging allows for the measurement of structural, functional, and metabolic integrity of the brain at the level of voxels, whose volumes are on the order of mm³. These voxelwise measurements provide a rich collection of disease indicators. Longitudinal neuroimaging studies enable the analysis of changes in these voxelwise measures. However, …

Madagascar’S Mangroves: Quantifying Nation-Wide And Ecosystem Specific Dynamics, And Detailed Contemporary Mapping Of Distinct Ecosystems, Trevor G. Jones, Leah Glass, Samir Gandhi, Lalao Ravaoarinorotsihoarana, Aude Carro, Lisa Benson, Harifidy Rakoto Ratsimba, Chandra Giri, Dannick Randriamanatena, Garth Cripps

Environmental Science and Management Faculty Publications and Presentations

Mangrove ecosystems help mitigate climate change, are highly biodiverse, and provide critical goods and services to coastal communities. Despite their importance, anthropogenic activities are rapidly degrading and deforesting mangroves world-wide. Madagascar contains 2% of the world’s mangroves, many of which have undergone or are starting to exhibit signs of widespread degradation and deforestation. Remotely sensed data can be used to quantify mangrove loss and characterize remaining distributions, providing detailed, accurate, timely and updateable information. We use USGS maps produced from Landsat data to calculate nation-wide dynamics for Madagascar’s mangroves from 1990 to 2010, and examine change more closely by partitioning …

3d Hydrodynamic Model Development And Verification, Hussein A. M. Al-Zubaidi

Civil and Environmental Engineering Master's Project Reports

A three-dimensional numerical model was developed to simulate hydrodynamic, temperature, and water quality distributions in rivers and lakes. In an attempt to get rid of the extra approximation and complexity, no coordinate transformation has been done and z-coordinate system has been employed. The governing equations are the continuity equation, free surface equation, momentum equations, and conservation equations of temperature and water quality. The model employs the time splitting technique which allows splitting the directions in which we end with two-dimensional governing equations and eventually the solution ends with a tri-diagonal matrix, which is easily solved by Thomas algorithm. The first …

Worldview-Based Scenarios Highlight Stakeholder Values And Assumptions, John Rueter

Environmental Science and Management Faculty Publications and Presentations

In lake management, we have the privilege and responsibility to work with the public on highly visible resources. Everybody has an opinion based on his or her personal values and observations. While we might sometimes consider this plethora of value statements as the bane of our existence, we all realize that public engagement is crucial for the health and future of lakes. Poor lake health is often caused by many little insults that stem from a wide range of legitimate views for how the lake should be treated as a resource. We need a framework to be able to deal …

Electrochemistry-Coupled To Mass Spectrometry In Simulation Of Metabolic Oxidation Of Methimazole: Identification And Characterization Of Metabolites, Kudzanai Chipiso, Reuben H. Simoyi

Chemistry Faculty Publications and Presentations

Methimazole (MMI), an antithyroid drug, is associated with idiosyncratic toxicity. Reactive metabolites resulting from bioactivation of the drug have been implicated in these adverse drug reactions. Mimicry of enzymatic oxidation of MMI was carried out by electrochemically oxidizing MMI using a coulometric flow-through cell equipped with a porous graphite working electrode. The cell was coupled on-line to electrospray ionization mass spectrometry (EC/ESI-MS). ESI spectra were acquired in both negative and positive modes. In acidic medium, ESI spectral analysis showed that the dimer was the main product, while in neutral and basic media, methimazole sulfenic acid, methimazole sulfinic acid and methimazole …

Theoretical Estimates Of Spherical And Chromatic Aberration In Photoemission Electron Microscopy, Joseph P. S. Fitzgerald, Robert Campbell Word, Rolf Kӧnenkamp

Physics Faculty Publications and Presentations

We present theoretical estimates of the mean coefficients of spherical and chromatic aberration for low energy photoemission electron microscopy (PEEM). Using simple analytic models, we find that the aberration coefficients depend primarily on the difference between the photon energy and the photoemission threshold, as expected. However, the shape of the photoelectron spectral distribution impacts the coefficients by up to 30%. These estimates should allow more precise correction of aberration in PEEM in experimental situations where the aberration coefficients and precise electron energy distribution cannot be readily measured.

Emerging Adaptive Architectures For Biomolecular Computation, Matthew Fleetwood

Undergraduate Research & Mentoring Program

The goal of this work is to explore applications of reservoir computing in biomolecular computation. Reservoir computing is a unique model for representing a mapping from one instance in time to a specific output. A neural network of randomly connected neurons is linked with a single output neuron or multiple output neurons. The output neurons are capable of mapping inputs to desired outputs using adaptable algorithms. This framework is investigated by using the Python programming language and object oriented design and programming. Neurons are created in programs by bundling information like input data and attributes of the network, which utilize …

Complex Capillary Fluidic Phenomena For Passive Control Of Liquids In Low-Gravity Environments, Logan Torres

Undergraduate Research & Mentoring Program

In an effort to further apply the recent results of puddle jumping research, we seek to expand the oblique droplet impact studies of others by exploiting large liquid droplets in the near weightless environment of a drop tower. By using the spontaneous puddle jump mechanism, droplets of volumes 1 mL ≤ V ≤ 3 mL with corresponding Weber numbers of We ≈ 1 are impinged on surfaces inclined in the range 40° ≤ α ≤ 80° (measured from the horizontal plane). Impact surface wetting characteristics exhibit static contact angles θstatic = 165 ± 5°. All impacts result in complete rebound. …