Physical Sciences and Mathematics Commons^™

Investigating The Unique Reactivity Of Novel Hx (X=Cl, Br) Reagents With Alkenes And Alkynes., Rene E. Ebule

Electronic Theses and Dissertations

The addition of hydrogen halides to carbon-carbon unsaturated systems is a classic synthetic transformation that gives rise to a variety of halogenated products as well as building blocks.¹ The different routes to achieve hydrohalogenation make use of the hydrogen halides either in the gaseous form² or in solution³, or their surrogates⁴. Only second to dihalogens, hydrogen halides are the most atom efficient source of halogenation. However, hydrogen halides are reactive gases at ambient temperature, posing a major challenge in their application. Handling gaseous hydrogen halide reagents requires expert knowledge and specialized equipment. We have …

Assessing Land Deformation And Sea Encroachment In The Nile Delta: A Radar Interferometric And Modeling Approach, Esayas Gebrekidan Gebremichael

Dissertations

Many of the deltas of the world are experiencing land deformation, subsidence or uplift of landmass, due to natural or anthropogenic causes, or a combination of both processes and causes. These deltaic settings are densely populated and border some of our world’s largest water bodies (oceans and seas). The land deformation, especially the subsidence component, when combined with the climate change-induced sea level rise, coastal erosion, and other anthropogenic drivers, will undoubtedly impact the population and economy of coastal areas of deltas. For the Nile Delta of Egypt, the land deformation processes and the factors that control the deformation processes …

Radiative Double Electron Capture (Rdec) By Fully-Stripped Fluorine Ions In Collisions With Nitrogen, Nuwan Sisira Kumara

Dissertations

Radiative double electron capture (RDEC) by highly-stripped ions in collisions with atomic targets is a fundamental process that can be used to study electron-electron correlation, the interaction between two electrons, in the vicinity of the Coulomb field of a bare ion. In this process two electrons from the target are captured to bound states of the projectile with the simultaneous emission of a single photon. RDEC is closely related to the well-known one-step atomic process of radiative electron capture (REC), in which a target electron is captured to the projectile and a photon is simultaneously emitted. REC and RDEC can …

Generalized Line Graphs, Mohra Abdullah Z. Alqahtani

Dissertations

With every nonempty graph, there are associated many graphs. One of the best known and most studied of these is the line graph L (G) of a graph G, whose vertices are the edges of G and where two vertices of L (G) are adjacent if the corresponding edges of G are adjacent. This concept was implicitly introduced by Whitney in 1932. Over the years, characterizations of graphs that are line graphs have been given, as well as graphs whose line graphs have some specified property. For example, Beineke characterized graphs that are line graphs by forbidding certain graphs …

Protecting Privacy Of Data In The Internet Of Things With Policy Enforcement Fog Module, Abduljaleel Al-Hasnawi

Dissertations

The growth of IoT applications has resulted in generating massive volumes of data about people and their surroundings. Significant portions of these data are sensitive since they reflect peoples' behaviors, interests, lifestyles, etc. Protecting sensitive IoT data from privacy violations is a challenge since these data need to be handled by public networks, servers and clouds, most of which are untrusted parties for data owners. In this study, a solution called Policy Enforcement Fog Module (PEFM) is proposed for protecting sensitive IoT data. The primary task of the PEFM solution is mandatory enforcement of privacy polices for sensitive IoT data-whenever …

Relative Permittivity As A Function Of Co-Solvent And Impedance Spectroscopy For Quantifying Anions In Solution, Yahya Sami Alseiha

Electronic Theses and Dissertations

This work measured relative permittivity from 15.0 to 55.0 °C of aqueous solutions containing acetone or tetrahydrofuran using a BI 870 dielectric meter. A cubic polynomial fit resulted in coefficients for calculating permittivity as a function of temperature and mole fraction. Literature values for other co-solvent system resulted in similar polynomial coefficients. Using BI 870, permittivity measurements of ionic solutions were not possible because of high conductivity. A simple method using impedance spectroscopy measured these solutions. Impedance decreases with increasing temperature and decreases with increasing ionic strength. Due to the temperature dependence of impedance, all measurements were at 25.0 °C. …

Multi-Base Chains For Faster Elliptic Curve Cryptography, Saud Al Musa

Theses and Dissertations

This research addresses a multi-base number system (MBNS) for faster elliptic curve cryptography (ECC). The emphasis is on speeding up the main operation of ECC: scalar multiplication (tP). Mainly, it addresses the two issues of using the MBNS with ECC: deriving optimized formulas and choosing fast methods. To address the first issue, this research studies the optimized formulas (e.g., 3P, 5P) in different elliptic curve coordinate systems over prime and binary fields. For elliptic curves over prime fields, affine Weierstrass, Jacobian Weierstrass, and standard twisted Edwards coordinate systems are reviewed. For binary elliptic curves, affine, Lambda-projective, and twisted mu4-normal coordinate …

3d Shape Descriptor-Based Facial Landmark Detection: A Machine Learning Approach, Reihaneh Rostami

Theses and Dissertations

Facial landmark detection on 3D human faces has had numerous applications in the literature

such as establishing point-to-point correspondence between 3D face models which is itself a

key step for a wide range of applications like 3D face detection and authentication, matching,

reconstruction, and retrieval, to name a few.

Two groups of approaches, namely knowledge-driven and data-driven approaches, have been

employed for facial landmarking in the literature. Knowledge-driven techniques are the

traditional approaches that have been widely used to locate landmarks on human faces. In

these approaches, a user with sucient knowledge and experience usually denes features to

be extracted …

Creating Singapore’S Longest Monthly Rainfall Record From 1839 To The Present, Elaine Gao, Bertrand Timbal, Fiona Williamson

Research Collection School of Social Sciences

Currently,the identification of decadal variability is limited by the lack of long-termmeteorological datasets; Singapore’s reliable contemporary network of automaticmeteorological stations (AWS) provides only about 30 years of rainfall data for thewhole island. In this study, rainfall data, sourced fromhistorical archives and recording monthly rainfall pre-dating the start ofofficial MacRitchie observations, are compiled from various locations acrossthe island. By making use of the contemporary AWS network, we evaluate thespatial relationship of rainfall between the historical sites and the currentMacRitchie site. This enables us to reconstruct historical rainfall atMacRitchie using the archive data, thereby building a single-location extendedrainfall record (though discontinuous) from …

Compositional And Thermodynamic Variability In A Stratified Magma Chamber: Evidence From The Green Tuff Ignimbrite (Pantelleria, Italy)., Katarzyna M. Liszewska, John C. White, Ray Macdonald, Bogusław Bagiński

EKU Faculty and Staff Scholarship

The Green Tuff Ignimbrite, Pantelleria, is compositionally zoned from pantellerite at the base to comenditic trachyte at the top, the variation apparently representing an inverted vertical zonation in the pre-eruptive reservoir. The main phenocryst assemblages are alkali feldspar + olivine + clinopyroxene + ilmenite + apatite in the trachytes and alkali feldspar + aenigmatite + clinopyroxene + quartz in the rhyolites. Thermodynamic modelling indicates that the temperature range was ~900–700°C, fO2 FMQ –1.5 to FMQ –0.5 (where FMQ is fayalite–magnetite–quartz buffer) and aSiO2 (relative to quartz saturation) 0.74–1.00. Melt water contents ranged from ~1wt % in the trachytes to ~4wt …

Multidecadal Variability In Climate Models And Observations, Alex Carl Oser

Theses and Dissertations

Climate change attribution and prediction using state-of-the-art models continue to garner an ever-growing focus amongst both the scientific community and public alike. Recent analyses showing discrepancies in the structure of modeled and observed decadal climate variability (DCV), therefore, have engendered efforts to not only diagnose the dynamics underpinning observed DCV, but also to characterize the behavior of DCV within climate models. In this thesis, we employ Multichannel Singular Spectrum Analysis (M-SSA) to show that while the DCV signal in observations is best described as a coherent oscillation with complex propagation across the globe, modeled DCV lacks this structure altogether. Specifically, …

The Effects Of Seasonal Variations In Chemistry And Hydrology On The Microbial Community And Its Sulfide Oxidation Potential In A Naturally Acidic Maine Stream, Raymond C. Kahler Iii

Electronic Theses and Dissertations

Sulfide minerals oxidize through interaction with water and oxygen, releasing hydrogen ions. The process often occurs naturally near metal sulfide deposits, and can be accelerated through mining. Microorganisms accelerate the rate of sulfide oxidation. Acidified streams typically contain high metal concentrations (e.g. aluminum) and microbes in these systems may develop resistances to metal toxicity. Stream flow can affect sulfide oxidation and microbial community structure. Baseflow can influence stream chemistry from interactions with the surrounding bedrock, while stormflow affects stream chemistry and the local microbial community through dilution and addition of microbes transported by runoff. Microbial community composition is affected by …

Book Review: Life On Mars: What To Know Before We Go, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Life on Mars: what to know before we go. Princeton, 2018. 302p index ISBN 9780691180533, $29.95; ISBN 9781400889945 ebook, contact publisher for price.

Dispersion Analysis Of Hdg Methods, Jay Gopalakrishnan, Manuel Solano, Felipe Vargas

Mathematics and Statistics Faculty Publications and Presentations

This work presents a dispersion analysis of the Hybrid Discontinuous Galerkin (HDG) method. Considering the Helmholtz system, we quantify the discrepancies between the exact and discrete wavenumbers. In particular, we obtain an analytic expansion for the wavenumber error for the lowest order Single Face HDG (SFH) method. The expansion shows that the SFH method exhibits convergence rates of the wavenumber errors comparable to that of the mixed hybrid Raviart–Thomas method. In addition, we observe the same behavior for the higher order cases in numerical experiments.

Along-Shelf Connectivity And Circumpolar Gene Flow In Antarctic Silverfish (Pleuragramma Antarctica), Jilda Alicia Caccavo, Chiara Papetti, Maj Wetjen, Rainer Knust, Julian R. Ashford, Lorenzo Zane

OES Faculty Publications

The Antarctic silverfish (Pleuragramma antarctica) is a critically important forage species with a circumpolar distribution and is unique among other notothenioid species for its wholly pelagic life cycle. Previous studies have provided mixed evidence of population structure over regional and circumpolar scales. The aim of the present study was to test the recent population hypothesis for Antarctic silverfish, which emphasizes the interplay between life history and hydrography in shaping connectivity. A total of 1067 individuals were collected over 25 years from different locations on a circumpolar scale. Samples were genotyped at fifteen microsatellites to assess population differentiation and …

Parallel Sampling-Pipeline For Indefinite Stream Of Heterogeneous Graphs Using Opencl For Fpgas, Muhammad Usman Tariq, Fahad Saeed

School of Computing and Information Sciences

In the field of data science, a huge amount of data, generally represented as graphs, needs to be processed and analyzed. It is of utmost importance that this data be processed swiftly and efficiently to save time and energy. The volume and velocity of data, along with irregular access patterns in graph data structures, pose challenges in terms of analysis and processing. Further, a big chunk of time and energy is spent on analyzing these graphs on large compute clusters and/or data-centers. Filtering and refining of data using graph sampling techniques are one of the most effective ways to speed …

Unveiling Charge-Separation Dynamics In Cds/Metal–Organic Framework Composites For Enhanced Photocatalysis, Hai-Qun Xu, Sizhuo Yang, Xing Ma, Jier Huang, Hai-Long Wang

Chemistry Faculty Research and Publications

Photocatalytic water splitting for H₂ production becomes one of the most favorable pathways for solar energy utilization, while the charge-separation dynamics in composite photocatalysts is largely elusive. In the present work, CdS-decorated metal–organic framework (MOF) composites, namely, CdS/UiO-66, have been synthesized and exhibit high H₂ production activity from photocatalytic water splitting, far surpassing the MOF and CdS counterparts, under visible light irradiation. Transient absorption (TA) spectroscopy has been adopted in this report to unveil the charge-separation dynamics in CdS/UiO-66 composites, a key process that dictates their function in photocatalysis. We show that, in addition to the preferable formation …

Concurrency Analysis In Javascript Programs Using Arrows, Joshua Cochrane

Theses and Dissertations

Concurrency errors are difficult to detect and correct in asynchronous programs such as those implemented in JavaScript. One reason is that it is often difficult to keep track of which parts of the program may execute in parallel and potentially share resources in unexpected, and perhaps unintended, ways. While programming constructs such as promises can help improve the readability of asynchronous JavaScript programs that were traditionally written using callbacks, there are no static tools to identify asynchronous functions that run in parallel, which may potentially cause concurrency errors.

In this work, we present a solution for implementing JavaScript programs using …

Cost-Effective Load Scheduling For Hybrid Renewable Energy Systems, Avinash Shashikala Rajendra

Theses and Dissertations

Hybrid renewable energy systems offer great promise for the future. However, some lingering concerns regarding stability and cost efficiency still exist. If a private party installs the system and maintains full control, the party may itself alleviate some of these problems by wisely optimizing the benefits offered by the system. One of the ways to do so is to develop a schedule for their load such that the cost incurred is minimized; this is done by maximally utilizing the renewable sources of energy before using the backup options of more conventional energy sources. Creating such a schedule involves considering several …

Shorter And Improved Access To The Key Tetracyclic Core Of Sarpagine-Macroline-Ajmaline Indole Alkaloids: The Total Synthesis Of Alkaloids Macrocarpines A-G, Talcarpine, N(4)-Methyl-N(4),21-Secotalpinine, Deoxyperaksine, Dihydroperaksine, Talpinine, O-Acetyltalpinine, And N(4)-Methyltalpinine, Md Toufiqur Rahman

Theses and Dissertations

Extension of the asymmetric Pictet-Spengler (P-S) reaction to bulkier Nb-alkylated tryptophan derivatives resulted in a shorter and improved stereospecific access to the key bicyclo[3.3.1]nonane framework of bioactive C-19 methyl substituted sarpagine/macro-line/ajmaline indole alkaloids with excellent diastereoselectivity via internal asymmetric induction. The asymmetric Pictet-Spengler/Dieckmann protocol with bulky Nb-alkyl substituted systems enabled a more direct and two-step shorter route to this key architecture. Complete stereocontrol of the C-19 methyl function in either the α- or β-configuration was achieved which would enable one to gain rapid access to the crucial intermediates for the total synthesis of any member of this group of seventy …

Graphene-Based Materials Coated On Zeolite For The Removal Of Persistent Organic Pollutants From Water, Yan Zhang

Theses and Dissertations

Adsorption is a fast, low-cost and the most commonly implemented water treatment technology for the removal of multiple contaminations from ground water, drinking water or wastewater. Difficulties in removing persistent organic pollutants (POPs) to improve quality and safety of treated water sources require the exploration of novel and multifunctional materials. Graphene-based materials having unique structures, high specific surface areas and tailorable functional groups are promising candidates as adsorbents.

The main goal of this work is to fabricate a novel adsorbent made of GO/rGO attached on natural zeolite substrates for the removal of variably charged organic model compounds and POPs in …

The Influence Of Mechanical Stratigraphy On Thrust-Ramp Nucleation And Propagation Of Thrust Faults, Sarah S. Wigginton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Our current understanding of thrust fault kinematics predicts that thrust faults nucleate on low angle, weak surfaces before they propagate upward and forms a higher angle ramp. While this classic kinematic and geometric model serves well in some settings, it does not fully consider the observations of footwall deformation beneath some thrust faults. We examine an alternative end-member model of thrust fault formation called “ramp-first” fault formation. This model hypothesizes that in mechanically layered rocks, thrust ramps nucleate in the structurally strong units, and that faults can propagate both upward and downward into weaker units forming folds at both fault …

Energy And Risk: Discourse, Framing, And Content, Temis Gardner Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research examined how people communicate and create knowledge about energy-related risks. Analysis of the discourse, frames, and content surrounding unconventional energy policy and development in the Western United States was conducted using three case studies. The results contribute to an understanding of energy-related risk perceptions in social and historical contexts.

Discourses contained in newspapers and public comments to the Bureau of Land Management presented arguments on the basis of risks to the environment; climate; human health and safety; jobs and economic prosperity; property rights; and local governments. Governments were seen as risks when they were perceived to allow misuse …

Mesospheric Gravity Wave Climatology And Variances Over The Andes Mountains, Jonathan Rich Pugmire

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Look up! Travelling over your head in the air are waves. They are present all the time in the atmosphere all over the Earth. Now imagine throwing a small rock in a pond and watching the ripples spread out around it. The same thing happens in the atmosphere except the rock is a thunderstorm, the wind blowing over a mountain, or another disturbance. As the wave (known as a gravity wave) travels upwards the thinning air allows the wave to grow larger and larger. Eventually the gravity wave gets too large – and like waves on the beach – it …

Fusulinid And Conodont Biostratigraphy Of The Upper Pennsylvanian–Cisuralian Riepe Spring Limestone, Spruce Mountain Ridge, Elko County, Nevada, U.S.A., Michael Taylor Read

Earth & Environmental Sciences Dissertations

The Upper Pennsylvanian-Cisuralian (lower Permian) mixed carbonate-siliciclastic strata exposed at Spruce Mountain Ridge, Elko County, Nevada, record the shallow-marine microfauna and oscillating depositional history of the Ferguson Trough during the final glacial interval of the late Paleozoic ice age. The 420 m thick North Spruce Mountain Ridge (NSMR) section includes the uppermost part of the Ely Limestone, the Riepe Spring Limestone, and the base of the Rib Hill Formation. A discontinuous Pennsylvanian-Permian transition is preserved within the approximately 390 m thick Riepe Spring Limestone along the west side of Spruce Mountain Ridge, where an erosional disconformity separates upper Gzhelian (Upper …

Geochemical Evolution Of The Iron Ore Group -- A Mid-Archean Greenstone Belt Of The Eastern Indian Craton, Jordan Kent Wright

Earth & Environmental Sciences Theses

The Iron Ore Group (IOG) greenstone belt is located along the Eastern Indian Shield. It preserves a mid-Archean segment of Earth’s history, which consists of conformable sequences of lower basaltic-andesitic lava at the base (~2 km), followed successively upwards by lower-shales (2.3 km) gradating into a tuffacious horizon (30 m at the top), an extensive Algoma-type banded-iron formation (0.7 km), upper basaltic-andesitic lava and upper-shales (~3 km). This succession provides ideal investigative conditions considering each stratigraphic unit as only been lightly-metamorphosed to the low greenschist facies, lacks penetrative deformation, preserves pristine depositional characteristics and great antiquity (~3.4 Ga). The concentrations …

Online Bioanalytical Mass Spectrometry Methods For Analysis Of Small And Large Biomolecules Using One- And Two-Dimensional Liquid Chromatography, Yehia Zakaria Baghdady

Chemistry & Biochemistry Dissertations

In recent years, the innovation in biomarkers and biotherapeutics has increased the demand for state-of-the-art analytical platforms to achieve reliable and accurate discoveries and quantitative analysis methods. The challenges in their determinations are not limited to the large number of small and large biomolecules but also involve the great heterogeneity in chemical properties and abundance of those analytes. Liquid chromatography and mass spectrometry have advanced significantly to be the most common platform for analyzing biological samples. However, there are still many unmet challenges that that require application of novel bioanalytical methods to fill many gaps in online sample preparation, chromatographic …

Development Of Highly Polar Structurally-Tuned Ionic Liquids With Unique Selectivity For Gas Chromatography, Mohsen Talebi

Chemistry & Biochemistry Dissertations

Ionic Liquids (ILs) are state-of-the-art fluids that have found broad application in separation science. Owing to their unique physicochemical properties such as low vapor pressure, high thermal stability, and high viscosity, they were successfully used as stationary phase in gas chromatography (GC). By properly engineering their molecular structure, ionic liquids with tailor-made properties can be designed. Therefore, a systematic structure-function relationship can be established to study the effect of structural modification on the properties of ionic liquids. Herein, I describe the design and synthesis of several dicationic ionic liquids. The synthesized ILs were characterized in terms their physicochemical properties. The …

Optimal Control Methods For Chagas Disease, Francis Mastrome

Mathematics Theses

Chagas disease is the world's most neglected tropical disease. Having a lack of cure makes the primary focus on the disease preventing it and controlling it. This study takes into account three different control measures: bed nets, low-volume insecticide spraying, and improving housing conditions, analyzes their cost effectiveness compared to each other, and determines which combination of the three control measures prevents the most T. cruzi infections in a rural Latin American village over a decade. It was shown that there is a a hierarchical importance in the control measures when preventing the spread of Chagas disease. In order of …

Mechanistic Study Of The Inhibition Of Rho Gtpase-Mediated Metastasis, Hope Gloria Umutesi

Chemistry & Biochemistry Dissertations

The Ras superfamily of small GTPases are monomeric proteins that bind guanine nucleotides, and regulate many cellular signaling pathways. They function as molecular switches by shuttling between active GTP-bound and inactive GDP-bound states. The Ras superfamily consists of its subfamilies including Ras and Rho GTPases. Ras and Rho GTPases function to regulate cellular growth, transformation, transport, motility, traffic, and adhesion. Small GTPases reactions often require regulators, such as guanine nucleotide exchange factors (GEFs) and GTPase Activating Proteins (GAPs). GEFs mediate fast release of GDP and allow loading with GTP while GAPs accelerate the GTP hydrolysis to GDP. Redox agents also …