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Full-Text Articles in Physical Sciences and Mathematics

Mass Spectrometry Based Metabolomics And Lipidomics., Fang Yuan Aug 2021

Mass Spectrometry Based Metabolomics And Lipidomics., Fang Yuan

Electronic Theses and Dissertations

Metabolomics and lipidomics studies are important to understand living organisms at the molecular level. In this dissertation, I conducted various untargeted and targeted metabolomics and lipidomics studies using mass spectrometry based analytical platforms. Firstly, I investigated the androgen depletion effects on fecal metabolites in a mouse model of systemic lupus erythematosus and metabolite biomarkers for colorectal cancer using two-dimensional gas and liquid chromatography-mass spectrometry. Secondly, I investigated the relationship between gut microbiota-mediated resistance and susceptibility to malaria and the production of short-chain fatty acids using gas chromatography-mass spectrometry. Thirdly, I developed a high-throughput liquid chromatography-mass spectrometry method to profile long-chain …


The Effects Of Prescribed Burning On Soil Water Infiltration Rates And Other Select Soil Physical And Chemical Properties In East Texas, Cassady Pennington Dunson, Brian P. Oswald, Kenneth Farrish, Tyson Hart Aug 2021

The Effects Of Prescribed Burning On Soil Water Infiltration Rates And Other Select Soil Physical And Chemical Properties In East Texas, Cassady Pennington Dunson, Brian P. Oswald, Kenneth Farrish, Tyson Hart

Electronic Theses and Dissertations

This study focused on whether prescribed burning affects soil physical and chemical properties, especially water infiltration, in Western Gulf Coast forests. Soil water infiltration rates were measured 1) pre-burn (before the fire), 2) post-burn (one month after the fire), and 3) at vegetation green-up (three months after the fire). Soil samples were also collected to determine the effects of prescribed burning on soil pH, bulk density, particle density, pore space, soil strength, O-horizon weight and depth (organic matter), water stable aggregates, and soil fertility. This project was conducted on two different burn intervals. The National Forests and Grasslands of Texas …


Investigations Of Elastin Recoil On Molecular And Macroscopic Levels., Nour Mohammad Jamhawi Aug 2021

Investigations Of Elastin Recoil On Molecular And Macroscopic Levels., Nour Mohammad Jamhawi

Electronic Theses and Dissertations

Elastin is one of the most hydrophobic proteins, and it is extremely flexible when hydrated. The driving force for recoil is the decrease in entropy of the protein and/or the hydrating solvent. This dissertation is a study of both mechanisms. Following an introduction (Chapter 1), Chapters 2 and 3 investigate the recoil mechanism on the molecular level in the hydrating solvent and in the protein, respectively. Chapter 4 examines macroscopic properties of recoil by thermomechanics. Conclusions are discussed in Chapter 5. Using double quantum NMR, the deuterated water ordering at the elastin surface was studied quantitatively as a function of …


High-Density Parking For Autonomous Vehicles., Parag J. Siddique Aug 2021

High-Density Parking For Autonomous Vehicles., Parag J. Siddique

Electronic Theses and Dissertations

In a common parking lot, much of the space is devoted to lanes. Lanes must not be blocked for one simple reason: a blocked car might need to leave before the car that blocks it. However, the advent of autonomous vehicles gives us an opportunity to overcome this constraint, and to achieve a higher storage capacity of cars. Taking advantage of self-parking and intelligent communication systems of autonomous vehicles, we propose puzzle-based parking, a high-density design for a parking lot. We introduce a novel method of vehicle parking, which leads to maximum parking density. We then propose a heuristic method …


Structural, Vibrational And Transport Properties Of Novel Complex Systems., Bhupendra Man Shing Karki Aug 2021

Structural, Vibrational And Transport Properties Of Novel Complex Systems., Bhupendra Man Shing Karki

Electronic Theses and Dissertations

Electron correlation effects in quantum materials are very strong. It is critical to investigate the structure of quantum materials to better understand and manipulate their physical properties. Quantum effects are prominent at the atomic microscopic length scale, which can not be examined by average long range structural measurements using traditional diffraction methods. Instead, pair distribution function (PDF) analysis, a local structure probe, can effectively unveil the mystery of local structure, which is more sensitive to local behavior than bulk average features. The first section of my dissertation will concentrate on the local structural study of the Iron oxy-chalcogenides, {\cSSe}, which …


Intercalation And High Pressure Studies Of Black Phosphorous - Pathways To Novel Materials And Physics., Manthila Chathurange Rajapakse Aug 2021

Intercalation And High Pressure Studies Of Black Phosphorous - Pathways To Novel Materials And Physics., Manthila Chathurange Rajapakse

Electronic Theses and Dissertations

Discovery of graphene in 2004 initiated a new trend of materials known as two-dimensional (2D) materials which have exciting surface properties and anisotropies than their bulk counterparts. Phosphorene, which is the layered version of black phosphorous (BP) is one of the top 2D materials in terms of research interests and applications of the present day. Moving a step further, our interest is to understand the possibilities for structural modifications of phosphorene, by means of stimuli such as intercalation and high-pressure. It has been predicted by theoretical studies that these stimuli may lead to the formation of new structures and phases …


Bayesian Variable Selection Strategies In Longitudinal Mixture Models And Categorical Regression Problems., Md Nazir Uddin Aug 2021

Bayesian Variable Selection Strategies In Longitudinal Mixture Models And Categorical Regression Problems., Md Nazir Uddin

Electronic Theses and Dissertations

In this work, we seek to develop a variable screening and selection method for Bayesian mixture models with longitudinal data. To develop this method, we consider data from the Health and Retirement Survey (HRS) conducted by University of Michigan. Considering yearly out-of-pocket expenditures as the longitudinal response variable, we consider a Bayesian mixture model with $K$ components. The data consist of a large collection of demographic, financial, and health-related baseline characteristics, and we wish to find a subset of these that impact cluster membership. An initial mixture model without any cluster-level predictors is fit to the data through an MCMC …


Electrochemical Characterization Of Surface-Immobilized Metal Nanostructures: Stability, Atomic Level Doping, Catalysis, And Sensing Applications., Badri Prasad Mainali Aug 2021

Electrochemical Characterization Of Surface-Immobilized Metal Nanostructures: Stability, Atomic Level Doping, Catalysis, And Sensing Applications., Badri Prasad Mainali

Electronic Theses and Dissertations

This dissertation has two main themes. The first theme involves voltammetric analysis of the stability of Au nanoparticles (NPs) under electrochemical and thermal treatment as a function of size, ligand stabilizer, and atomic composition. The second theme involves the use of Au NPs, electrophoretic deposition (EPD), and anodic stripping voltammetry (ASV) for electrochemical detection of analytes. The electrochemical size stability of 4.1, 15.1, and 50.3 nm average diameter Au NPs upon treatment with multiple electrochemical oxidation-reduction cycling in acidic electrolyte is monitored by observing changes in the peak oxidation potential (Ep) in ASV and the electrochemically measured surface …


Multilateration Index., Chip Lynch Aug 2021

Multilateration Index., Chip Lynch

Electronic Theses and Dissertations

We present an alternative method for pre-processing and storing point data, particularly for Geospatial points, by storing multilateration distances to fixed points rather than coordinates such as Latitude and Longitude. We explore the use of this data to improve query performance for some distance related queries such as nearest neighbor and query-within-radius (i.e. “find all points in a set P within distance d of query point q”). Further, we discuss the problem of “Network Adequacy” common to medical and communications businesses, to analyze questions such as “are at least 90% of patients living within 50 miles of a covered emergency …


Micelles And Lipid Nanoparticles: Catalysis And Biomedical Application., Faisal Ibrahim Aug 2021

Micelles And Lipid Nanoparticles: Catalysis And Biomedical Application., Faisal Ibrahim

Electronic Theses and Dissertations

RNA-based therapeutics is a rapidly expanding field due to its enormous potential for treatment of diseases through knockdown of genes or expression of therapeutic proteins. However, due to the overall negative-charge of an RNA molecule, RNA-based therapeutics must rely on delivery systems to overcome the various biological barriers for ultimate release of an RNA payload into the cytosol. Over the past three decades, the development of lipid-based RNA delivery systems, especially lipid nanoparticles (LNPs), have been comprehensively studied due to their unique properties. LNPs represent the most widely used delivery systems for RNA-based therapeutics, as evidenced by the clinical approvals …


Implementing Of Phase Potentiation Program With College Triathletes, David Fish Aug 2021

Implementing Of Phase Potentiation Program With College Triathletes, David Fish

Electronic Theses and Dissertations

The purpose of this study is to determine the effectiveness of an in-season resistance training program on improving measures of strength in female collegiate triathletes. Nine females (age = 19.2 ± 1.1 years, height = 166.5 ± 12.5 cm, body mass = 61.1 ± 9 kg) with limited resistance training experience were examined for this study. Formal RT intervention was monitored for 7 weeks with the athletes being assigned 6 weeks of independent RT prior to the pre-test. Athletes completed a standardized athlete monitoring program pre and post resistance training intervention. Paired sample t-tests were used to determine differences …


Mineralogical Restrictions On Porosity In The Taylor Sand Of The Cotton Valley Group, Northern Louisiana Salt Basin, Claiborne Parish, Louisiana, Kaleb C. Mcclain Jun 2021

Mineralogical Restrictions On Porosity In The Taylor Sand Of The Cotton Valley Group, Northern Louisiana Salt Basin, Claiborne Parish, Louisiana, Kaleb C. Mcclain

Electronic Theses and Dissertations

The Cotton Valley Group has been targeted for hydrocarbons since the 1940s. However, the reservoir was initially considered uneconomical to drill due to its low permeability and porosity. Since then, recent technological advances in hydraulic fracturing have allowed the Cotton Valley Sandstone members to become prolific, profitable plays, renewing interest in drilling and exploration across the northwest/northern Louisiana region.

In this research, mineralogical restrictions on the porosity in the Lower Taylor Sand of the Cotton Valley Group were studied from core (10,035’ft/3,059m -10,150’ft/3,094m) from Blackburn Field, northwest Claiborne Parish. Twelve samples were taken at intervals throughout the Taylor Sand, starting …


Precambrian Basement Influence On The Deposition Of The Upper Ordovician Utica Shale Play In East Central Ohio, William Kaleb Kirk Jun 2021

Precambrian Basement Influence On The Deposition Of The Upper Ordovician Utica Shale Play In East Central Ohio, William Kaleb Kirk

Electronic Theses and Dissertations

The Ordovician Utica shale play is a major oil and gas producing interval in the Appalachian Basin. The Utica shale play can be found as far as New York and Canada and to the south into Indiana and Kentucky. The play consists of the Trenton/Lexington limestones, Point Pleasant Formation, and Utica shale. The shallow marine fossiliferous limestones of the Trenton and shallow marine shaley limestones of the Lexington are overlain by an interbedded shale and limestone of the Point Pleasant Formation, which grade into the deeper marine interbedded shales and limey shales of the Utica. These formations are highly heterogeneous, …


Deposition And Diagenesis Of The Blossom Sand, Panola County, Texas, Hannah Chambers Jun 2021

Deposition And Diagenesis Of The Blossom Sand, Panola County, Texas, Hannah Chambers

Electronic Theses and Dissertations

The Late Cretaceous Blossom Sand within the Austin Group is a historic gas reservoir in the East Texas basin, located at depths of approximately 2,000 ft below the surface. Since the discovery of the Carthage Field in 1918 in the East Texas Basin, the Blossom Sand has produced approximately 26 BCF of gas with minor amounts of oil. Despite its notoriety in the Carthage Field, there is very little research that has been conducted on this unit, although it crops out in northeast Texas and is found in the subsurface of southwest Arkansas, western Louisiana, and the East Texas Basin. …


Eastward-Propagating Planetary Waves In The Middle Atmosphere During Major Sudden Stratospheric Warming Events, Christian Todd Rhodes May 2021

Eastward-Propagating Planetary Waves In The Middle Atmosphere During Major Sudden Stratospheric Warming Events, Christian Todd Rhodes

Electronic Theses and Dissertations

No abstract provided.


Radiosonde High Altitude Measurements Of Radiation Levels And Cosmic Ray Events, Ayodeji Opeyemi Akinuliola May 2021

Radiosonde High Altitude Measurements Of Radiation Levels And Cosmic Ray Events, Ayodeji Opeyemi Akinuliola

Electronic Theses and Dissertations

Just above us, cosmic rays are hurtling in from space. These fast moving particles crash uncontrollably into molecules in the atmosphere, causing spontaneous decays of these particles. Despite the fact that we are broadly shielded from this radiation on earth, these particles can still disturb humans and electronics alike. Therefore, this research focuses on expanding the use of long-range radio transmitters such as radiosondes to transmit valuable data such as cosmic ray flux, geographical position, atmospheric temperature, pressure, etc. This can improve real-time radiation monitoring for aviation industry crew and passengers working in potentially higher radiation environments. On March 11, …


Computational And Experimental Studies Of Functionalized Phenolic Tertiary Phosphine Oxides As Organocatalysts For The Redox-Neutral Mitsunobu Reaction, Sadie Brown May 2021

Computational And Experimental Studies Of Functionalized Phenolic Tertiary Phosphine Oxides As Organocatalysts For The Redox-Neutral Mitsunobu Reaction, Sadie Brown

Electronic Theses and Dissertations

The purpose of this thesis was the identification of a more efficient catalyst analog that could perform the redox-neutral Mitsunobu reaction, which was achieved via two synthetic pathways: elimination-addition and addition-rearrangement. Furthermore, a computational investigation was conducted on the conflicting interpretations of the catalytic cycle. Our research group replicated Houk et al. work, as well as expanded the computations to examine the influence different functional groups had on the ground state and transition state structures. Important ground state and transition state structures were determined, which provided a more energetically favorable pathway of the catalytic cycle. Experimental work demonstrated that both …


Quantification Of Persistent Organic Pollutants In Various Matrices Using Stir Bar Sorptive Extraction And Isotope Dilution Mass Spectrometry, Weier Hao May 2021

Quantification Of Persistent Organic Pollutants In Various Matrices Using Stir Bar Sorptive Extraction And Isotope Dilution Mass Spectrometry, Weier Hao

Electronic Theses and Dissertations

A method was developed to quantify persistent organic pollutants (POPs) in a wide range of matrices including wastewater, dietary supplements, and human whole blood using stir-bar sorptive extraction, GC-MS/MS, and isotope dilution mass spectrometry (IDMS). The method enabled accurate, precise, sensitive, and efficient quantification of POPs in these matrices. Compared with calibration curves, IDMS provided measurements with a higher level of accuracy and precision, especially at lower measured concentrations. The use of GC-MS/MS enabled a lower limit of quantification compared with GC-MS. A reverse-IDMS method was performed to further eliminate biases from the labelled concentrations of the commercially available standards. …


Air Pollution In The Steel City: Assessing The Influence Of Covid-19 On Air Pollution In Allegheny County, Carissa L. Lange May 2021

Air Pollution In The Steel City: Assessing The Influence Of Covid-19 On Air Pollution In Allegheny County, Carissa L. Lange

Electronic Theses and Dissertations

Though the novel coronavirus (COVID-19) has sickened millions of individuals, lockdown measures have provided a unique opportunity to analyze air pollution reductions. Reductions in air pollution are especially important in a city like Pittsburgh, where industrial activity has led to elevated levels of particulate matter with an aerodynamic diameter 2.5). The majority of this PM2.5 pollution comes from two industrial facilities, the Edgar Thomson Steel Works and the Clairton Coke Works. By utilizing a natural experiment, this study sought to determine how large of a role the COVID-19 lockdowns played in improving air quality in the Pittsburgh region. Data …


Geochemical Characterization Of The Utica Shale Play Using Xrf-Based Chemostratigraphy In Ohio, Barbara Kemeh, Julie M. Bloxson May 2021

Geochemical Characterization Of The Utica Shale Play Using Xrf-Based Chemostratigraphy In Ohio, Barbara Kemeh, Julie M. Bloxson

Electronic Theses and Dissertations

The Utica shale is an extensive gas shale play within the Appalachian Basin, expanding from Quebec through New York, into Pennsylvania, West Virginia and Ohio. Currently a target for gas exploration, it is also the source rock for much of the Paleozoic reservoirs throughout the basin. However, the Utica-Point Pleasant lithology varies significantly across the Appalachian Basin which can make it challenging to characterize.

The Utica shale Play consists of the Trenton/Lexington Limestones, Point Pleasant Formation and Utica shale. The Point Pleasant Formation and Utica shale are often grouped together, especially in Ohio because they are difficult to visually distinguish …


Electrodeposition Of Hydrogen Molybdenum Tungsten Bronze Films And Electrochemical Reduction Of Carbon Dioxide., Mohammad Bajunaid May 2021

Electrodeposition Of Hydrogen Molybdenum Tungsten Bronze Films And Electrochemical Reduction Of Carbon Dioxide., Mohammad Bajunaid

Electronic Theses and Dissertations

The foremost aim for performing this study was to focus on the electrodeposition of mixed hydrogen molybdenum tungsten bronze films, which have the potential for e– transfer interactions carrying out the reduction of carbon dioxide. A yellow peroxymolybdic tungstate solution was prepared and used for the electrodeposition of hydrogen molybdenum tungsten bronze films on conductive carbon paper. Electrodeposition was carried out at -2.0 V from 20 - 120 minutes to determine the effect of deposition time on film thickness and CO2 reduction. These films were characterized by X-ray photoelectron spectroscopy. The deposited films served as a working electrode …


Theranostic Nanoparticles Folic Acid-Carbon Dots-Drug(S) For Cancer, Godwin Kweku Babanyinah May 2021

Theranostic Nanoparticles Folic Acid-Carbon Dots-Drug(S) For Cancer, Godwin Kweku Babanyinah

Electronic Theses and Dissertations

This study aims to prepare theranostic nanoparticles (NPs) that are expected to increase cancer diagnostics and therapeutic efficacy. We prepared the NPs constituting carbon dots (CDs) as an imaging agent, folic acid as a targeting agent, doxorubicin (DOX), or gemcitabine (GEM) as chemotherapy agents. The NPs include noncovalent FA-CDs-DOX, covalent CDs-FA-DOX, and covalent FA-CDs-GEM. Through ultraviolet-visible spectroscopy, fluorescence spectroscopy, and Fourier transform-infrared spectroscopy, the fabrication of these NPs was confirmed. It was discovered that the high drug loading efficiency is the noncovalent series while the high drug loading capacity is the covalent series The in-vitro pH-dependent drug release data indicate …


Zeta Function Regularization And Its Relationship To Number Theory, Stephen Wang May 2021

Zeta Function Regularization And Its Relationship To Number Theory, Stephen Wang

Electronic Theses and Dissertations

While the "path integral" formulation of quantum mechanics is both highly intuitive and far reaching, the path integrals themselves often fail to converge in the usual sense. Richard Feynman developed regularization as a solution, such that regularized path integrals could be calculated and analyzed within a strictly physics context. Over the past 50 years, mathematicians and physicists have retroactively introduced schemes for achieving mathematical rigor in the study and application of regularized path integrals. One such scheme was introduced in 2007 by the mathematicians Klaus Kirsten and Paul Loya. In this thesis, we reproduce the Kirsten and Loya approach to …


Plprepare: A Grammar Checker For Challenging Cases, Jacob Hoyos May 2021

Plprepare: A Grammar Checker For Challenging Cases, Jacob Hoyos

Electronic Theses and Dissertations

This study investigates one of the Polish language’s most arbitrary cases: the genitive masculine inanimate singular. It collects and ranks several guidelines to help language learners discern its proper usage and also introduces a framework to provide detailed feedback regarding arbitrary cases. The study tests this framework by implementing and evaluating a hybrid grammar checker called PLPrepare. PLPrepare performs similarly to other grammar checkers and is able to detect genitive case usages and provide feedback based on a number of error classifications.


Constructions & Optimization In Classical Real Analysis Theorems, Abderrahim Elallam May 2021

Constructions & Optimization In Classical Real Analysis Theorems, Abderrahim Elallam

Electronic Theses and Dissertations

This thesis takes a closer look at three fundamental Classical Theorems in Real Analysis. First, for the Bolzano Weierstrass Theorem, we will be interested in constructing a convergent subsequence from a non-convergent bounded sequence. Such a subsequence is guaranteed to exist, but it is often not obvious what it is, e.g., if an = sin n. Next, the H¨older Inequality gives an upper bound, in terms of p ∈ [1,∞], for the the integral of the product of two functions. We will find the value of p that gives the best (smallest) upper-bound, focusing on the Beta and Gamma integrals. …


Machine Learning Approaches To Dribble Hand-Off Action Classification With Sportvu Nba Player Coordinate Data, Dembe Stephanos May 2021

Machine Learning Approaches To Dribble Hand-Off Action Classification With Sportvu Nba Player Coordinate Data, Dembe Stephanos

Electronic Theses and Dissertations

Recently, strategies of National Basketball Association teams have evolved with the skillsets of players and the emergence of advanced analytics. One of the most effective actions in dynamic offensive strategies in basketball is the dribble hand-off (DHO). This thesis proposes an architecture for a classification pipeline for detecting DHOs in an accurate and automated manner. This pipeline consists of a combination of player tracking data and event labels, a rule set to identify candidate actions, manually reviewing game recordings to label the candidates, and embedding player trajectories into hexbin cell paths before passing the completed training set to the classification …


Investigating The Role Of Charge Separation In Triplet State Formation In Zinc Dipyrrin Photosensitizers, Irene Y. Dzaye May 2021

Investigating The Role Of Charge Separation In Triplet State Formation In Zinc Dipyrrin Photosensitizers, Irene Y. Dzaye

Electronic Theses and Dissertations

About 85% of the world’s energy is derived from non-renewable sources—coal, petroleum, and natural gas. Solar photocatalysis is one way to potentially generate cheap renewable fuels by harnessing energy from the sun using a photosensitizer and converting it into chemical energy. The efficiency of a photosensitizer depends on its capacity to form a prolonged triplet excited state. Zinc dipyrrin complexes have the potential to be efficient sensitizers for reductive photochemistry, but their ability to form long-lived triplet excited states still needs extensive research. The overall aim of this research is to probe the role charge separation plays in the formation …


Gravel Geology And Muskoxen Paleontology Of A Late Pleistocene Fossil Site In Saltville, Virginia, Nickolas A. Brand May 2021

Gravel Geology And Muskoxen Paleontology Of A Late Pleistocene Fossil Site In Saltville, Virginia, Nickolas A. Brand

Electronic Theses and Dissertations

Two distinct studies within the Saltville Valley of southwestern Virginia revealed insights into local Pleistocene geology and paleontology. A variety of analytical techniques were applied to gravel deposits within the paleontological site of SV-5/7 that revealed this unit is very poorly sorted, has a subangular matrix, and contains significant components of silt and sand in addition to rounded cobbles. These results suggest that rather than being deposited by fluvial processes as previously suggested, these gravels were likely the result of one or many debris flows. Additionally, the identity of fossil muskoxen from Saltville was reassessed using cranial and dental material. …


Performance Comparison Of Multiple Imputation Methods For Quantitative Variables For Small And Large Data With Differing Variability, Vincent Onyame May 2021

Performance Comparison Of Multiple Imputation Methods For Quantitative Variables For Small And Large Data With Differing Variability, Vincent Onyame

Electronic Theses and Dissertations

Missing data continues to be one of the main problems in data analysis as it reduces sample representativeness and consequently, causes biased estimates. Multiple imputation methods have been established as an effective method of handling missing data. In this study, we examined multiple imputation methods for quantitative variables on twelve data sets with varied sizes and variability that were pseudo generated from an original data. The multiple imputation methods examined are the predictive mean matching, Bayesian linear regression and linear regression, non-Bayesian in the MICE (Multiple Imputation Chain Equation) package in the statistical software, R. The parameter estimates generated from …


Observational Studies In Group Testing And Potential Applications., Alexander Christopher Noll May 2021

Observational Studies In Group Testing And Potential Applications., Alexander Christopher Noll

Electronic Theses and Dissertations

The use of group testing to identify individuals with targeted outcomes in a population can greatly improve the efficiency, speed, and cost effectiveness of testing a population for an outcome, or at least for identifying the prevalence of an outcome in a population. The implementation of causal inference techniques can provide the basis for an observational study that would allow an investigator to gather estimates for treatment effectiveness if group testing was conducted on the population in a certain way. This thesis examines a simulation of the above outlined principles in order to demonstrate a potential application for determining treatment …