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The View From Ventress - 2016, University Of Mississippi. College Of Liberal Arts Jan 2016

The View From Ventress - 2016, University Of Mississippi. College Of Liberal Arts

Liberal Arts Newsletters

Special Section: Collabortions. To better understand the world and to tackle its complex problems, collaboration between disciplines offers a critical path forward. Faculty research and teaching interests to give students multidisciplinary educational opportunities. In this special section, we present the latest offerings in the College—two new minors, a new integrated fine arts course, and integrated science courses—along with a glimpse of the other multidisciplinary majors and minors.


Reducing Cache Contention On Gpus, Kyoshin Choo Jan 2016

Reducing Cache Contention On Gpus, Kyoshin Choo

Electronic Theses and Dissertations

The usage of Graphics Processing Units (GPUs) as an application accelerator has become increasingly popular because, compared to traditional CPUs, they are more cost-effective, their highly parallel nature complements a CPU, and they are more energy efficient. With the popularity of GPUs, many GPU-based compute-intensive applications (a.k.a., GPGPUs) present significant performance improvement over traditional CPU-based implementations. Caches, which significantly improve CPU performance, are introduced to GPUs to further enhance application performance. However, the effect of caches is not significant for many cases in GPUs and even detrimental for some cases. The massive parallelism of the GPU execution model and the …


The Effect Of Hyperparameters In The Activation Layers Of Deep Neural Networks, Clay Lafayette Mcleod Jan 2016

The Effect Of Hyperparameters In The Activation Layers Of Deep Neural Networks, Clay Lafayette Mcleod

Electronic Theses and Dissertations

Deep neural networks (DNNs), and artificial neural networks (ANNs) in general, have recently received a great amount of attention from both the media and the machine learning community at large. DNNs have been used to produce world-class results in a variety of domains, including image recognition, speech recognition, sequence modeling, and natural language processing. Many of most exciting recent deep neural network studies have made improvements by hardcoding less about the network and giving the neural network more control over its own parameters, allowing flexibility and control within the network. Although much research has been done to introduce trainable hyperparameters …


Temperature And Pressure Effects On Elastic Properties Of Relaxor Ferroelectrics And Thermoelectrics: A Resonant Ultrasound Spectroscopy Study, Sumudu Tennakoon Jan 2016

Temperature And Pressure Effects On Elastic Properties Of Relaxor Ferroelectrics And Thermoelectrics: A Resonant Ultrasound Spectroscopy Study, Sumudu Tennakoon

Electronic Theses and Dissertations

Relaxor ferroelectric lead magnesium niobate-lead titanate (PMN-PT) material exhibits exceptional electromechanical properties. The material undergoes a series of structural phase transitions with changes in temperature and the chemical composition. The work covered in this dissertation seek to gain insight into the phase diagram of PMN-PT using temperature and pressure dependence of the elastic properties. Single crystal PMN-PT with a composition near morphotropic phase boundary (MPB) was investigated using a resonant ultrasound spectroscopy (RUS) methodologies in the temperature range of 293 K - 800 K and the pressure range from near vacuum to 3.4 MPa. At atmospheric pressure, significantly high acoustic …


Characterization Of Charge Accommodation In Biologically Important Hydrogen-Bonded Clusters, John Thomas Kelly Jan 2016

Characterization Of Charge Accommodation In Biologically Important Hydrogen-Bonded Clusters, John Thomas Kelly

Electronic Theses and Dissertations

The underlying motivation of chemical physics and physical chemistry is to understand naturally occurring chemical and physical processes from the nanoscopic molecular level to the macroscopic condensed phase. Over the past half-century, experimentalists have developed a number of laser-based analytical techniques to bridge the gap between the bulk phase and the single molecule. Here, we look at bulk phase and gas phase clusters to compare the local hydrogen-bonded network. To better understand the role noncovalent interactions have on biologically relevant building blocks in a natural environment, we compare the microhydration of gas phase cluster ions to condensed phase spectra. The …


Contribution Of Shallow Geology To Hydrocarbon Seep Formation In Green Canyon Block 600, Samantha Lynn Lucker Jan 2016

Contribution Of Shallow Geology To Hydrocarbon Seep Formation In Green Canyon Block 600, Samantha Lynn Lucker

Electronic Theses and Dissertations

The Green Canyon Federal Protraction area in the Gulf of Mexico is rich in hydrocarbons. The movement of the Sigsbee salt escarpment in green canyon has resulted in a complex bathymetric profile and extensive shallow faulting that has allomigration of hydrocarbons to the surface creating cold seep sites. Green Canyon block 600 (gc600) contains multiple naturally occurring, active hydrocarbon seeps. Multi-beam bathymetry, backscatter, and polarity preserving chirp data were collected for gc600 to study the development of these naturally occurring seeps. Using these data, the structure and sedimentation of the first fifty meters can be studied in relation to the …


Robust Nickel Catalysts Supported By Biaryl-Bridged Pyridyl-N-Heterocyclic Carbenes For Carbon Dioxide Reduction To Value-Added Products, Hunter Allen Dulaney Jan 2016

Robust Nickel Catalysts Supported By Biaryl-Bridged Pyridyl-N-Heterocyclic Carbenes For Carbon Dioxide Reduction To Value-Added Products, Hunter Allen Dulaney

Electronic Theses and Dissertations

Carbon dioxide is a greenhouse gas, but also represents a readily accessible C1 feedstock for conversion to solar fuels and value-added chemicals. However, CO2 is relatively inert and very negative voltages or strong chemical reductants are comfor its conversion. An additional challenge lies in achieving these reactions in water where aqueous protons are utilized selectively for CO2 reduction rather than hydrogen generation. Our strategy for CO2 reduction involves the design of new homogeneous catalysts with tunable geometries and polyaromatic frameworks with increased delocalization to lower overpotentials for catalysis. We report a family of biaryl-bridged pyridyl-N-heterocyclic carbene-based ligands and their corresponding …


Obstacle-Aware Wireless Video Sensor Network Deployment For 3d Indoor Space Monitoring, Zhonghui Wang Jan 2016

Obstacle-Aware Wireless Video Sensor Network Deployment For 3d Indoor Space Monitoring, Zhonghui Wang

Electronic Theses and Dissertations

In recent years wireless video sensors networks (WVSNs) have emerged as a leading technology for monitoring 3D indoor space in campus, industrial and medical areas as well as other types of environments. In contrast to traditional sensors such as heat or light sensors often considered with omnidirectional sensing range, the sensing range of a video sensor is directional and can be deemed as a pyramid-shape in 3D. Moreover, in an indoor environment, there are often obstacles such as lamp stands or furniture, which introduce additional challenges and further render the deployment solutions for traditional sensors and 2D sensing field inapplicable …


The Porosity And Permeability Distribution Of The Shoal Grainstone And Thrombolitic Facies Of The Smackover Formation In Little Cedar Creek And Brooklyn Fields In Southwestern Alabama, Devin Thomas Jan 2016

The Porosity And Permeability Distribution Of The Shoal Grainstone And Thrombolitic Facies Of The Smackover Formation In Little Cedar Creek And Brooklyn Fields In Southwestern Alabama, Devin Thomas

Electronic Theses and Dissertations

The Smackover Formation is the most prolific hydrocarbon producer in Alabama, with the Little Cedar Creek and Brooklyn Fields being the two largest producers in Alabama. Unlike other Smackover fields Little Cedar Creek Field and Brooklyn Field production is the result of two reservoirs, known as the shoal grainstone and thrombolite (microbial) boundstone. Even with the success of the Smackover Formation, geographic trends of the porosity and permeability are problematic because production is affected. The distribution of the facies also plays a role in the porosity and permeability. The objective of this study is to delineate porosity and permeability trends …


Remobilization Of Cobalt, Copper, Nickel, Lead, And Zinc In A Riparian Wetland Model, Richard Glenn Dolly Jan 2016

Remobilization Of Cobalt, Copper, Nickel, Lead, And Zinc In A Riparian Wetland Model, Richard Glenn Dolly

Electronic Theses and Dissertations

The mobility of chemically persistent metals in riparian wetland systems that could have a detrimental impact on the environment is an area of active research. This study utilized a physical model consisting of open water and wetland cells designed to simulate a natural riparian wetland to examine the mobility of five metals. The objective of the study was to determine if riparian wetlands have the potential to serve as permanent sinks for metals, or if they only serve as temporary sinks and with time metals could be remobilized and released. Specifically, this study examined the long-term behavior of Co, Cu, …


On Variable Bandwidth Kernel Density And Regression Estimation, Janet Nakarmi Jan 2016

On Variable Bandwidth Kernel Density And Regression Estimation, Janet Nakarmi

Electronic Theses and Dissertations

We study the ideal variable bandwidth kernel density estimator introduced by McKay (1993) and the plug-in practical version of the variable bandwidth kernel density estimator with two sequences of bandwidths as in Ginè and Sang (2013).We estimate the variance of the variable bandwidth kernel density estimator. Based on the exact formula of the bias and the variance of the variable bandwidth kernel density estimator, we develop the optimal bandwidth selection of the true variable bandwidth kernel density estimator. Furthermore, we present the central limit theorem of the true variable bandwidth kernel density estimator. We also propose a new variable bandwidth …


Computation Of Acoustic Ressure Fields Produced In Feline Brain By High-Intensity Focused Ultrasound, Nazanin Omidi Jan 2016

Computation Of Acoustic Ressure Fields Produced In Feline Brain By High-Intensity Focused Ultrasound, Nazanin Omidi

Electronic Theses and Dissertations

In 1975, Dunn et al. (Jasa 58:512-514) shothat a simple relation describes the ultrasonic threshold for cavitation induced changes in the mammalian brain. The thresholds for tissue damage were estimated for a variety of acoustic parameters in exposed feline brain. The goal of this study was to improve the estimates for acoustic pressures and intensities present in vivo during those experimental exposures by estimating them using nonlinear rather than linear theory. In our current project, the acoustic pressure waveforms produced in the brains of anesthetized felines were numerically simulated for a spherically focused, nominally f1-transducer (focal length = 13 cm) …


Biophysical Characterization Of A Proline Mutant Of Neural Cadherin, Keshia S. Dykes Jan 2016

Biophysical Characterization Of A Proline Mutant Of Neural Cadherin, Keshia S. Dykes

Electronic Theses and Dissertations

Cadherins are calcium dependent glycoproteins whose homophilic interactions mediate cell-cell adhesion in solid tissues. They are comprised of an extracellular region, a transmembrane region and a cytoplasmic region. The extracellular region plays a critical role in cadherin-mediated cell adhesion, and has five tandemly repeated ectodomains (ec1-ec5), with three calcium binding sites situated in each interface between the domains. Dimerization of cadherin occurs through formation of adhesive interactions between extracellular domains of cadherins from neighboring cells. Adhesive interaction occurs at the interfaces of ec1 domains of two molecules originating from different cell surfaces. Dimerization is critically dependent on the binding of …


Synthesis And Characterization Of Anhydrous Proton Conducting Polymer Electrolytes For Fuel Cell Applications, Buddika Mayomi Liyanage Jan 2016

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 …


Raft Polymerization Of Ph-Responsive, Diblock Copolymers For Nucleic Acid Delivery Vehicles, Annie Katherine Mcclellan Jan 2016

Raft Polymerization Of Ph-Responsive, Diblock Copolymers For Nucleic Acid Delivery Vehicles, Annie Katherine Mcclellan

Electronic Theses and Dissertations

Since the development of gene therapy, a variety of non-viral nucleic acid delivery vehicles have been prepared and studied for their transfection efficiencies. Recently, polymeric gene delivery vehicles have gained popularity for their low immunogenicity and high transfection efficiency. With the advent of controlled radical polymerization (CRP) and more specifically reversible addition-fragmentation chain transfer (RAFT) polymerization, it is now possible to develop well-defined polymers with predicted molecular weights and architectures. The work presented here focuses on the RAFT polymerization of a family of amphiphilic, cationic copolymers to be utilized for nucleic acid delivery. These copolymers are composed of a stabilizing …


Diffusion And Invasion Percolation: A Coupled Model To Simulate The Fate Of Trapped And Compressed Gases In Partially-Saturated Low Permeability Media, Ross Berry Jan 2016

Diffusion And Invasion Percolation: A Coupled Model To Simulate The Fate Of Trapped And Compressed Gases In Partially-Saturated Low Permeability Media, Ross Berry

Electronic Theses and Dissertations

No abstract provided.


Cyclostratigraphy And Sedimentation Of The Cenomanian-Turonian Tuscaloosa Marine Shale, Christian Gilbert Kunhardt Jan 2016

Cyclostratigraphy And Sedimentation Of The Cenomanian-Turonian Tuscaloosa Marine Shale, Christian Gilbert Kunhardt

Electronic Theses and Dissertations

A cyclostratigraphic and geochemical analysis was conducted on the basal high resistivity zone of the Tuscaloosa Marine Shale to determine if orbital forcing is apparent in mineralogical data suites. Geochemical data suites obtained via x-ray diffraction from five cored wells located near the southern Mississippi/Louisiana border were used in the study. The results were used in concert with previously published insolation and biostratigraphic data and unpublished stable carbon isotope data to determine sedimentation rate, to identify and correlate the cretaceous oceanic anoxic event 2 (OAE 2) recovery period within the studied interval, and to determine the possible mechanisms of orbital …


Effect Of 5-Hydroxymethylcytosine Modifications On Stability Of Vegf I-Motifs, Bethany Summerford Jan 2016

Effect Of 5-Hydroxymethylcytosine Modifications On Stability Of Vegf I-Motifs, Bethany Summerford

Honors Theses

DNA i-motifs are a secondary structure of DNA formed at low pH by internal folding of strands rich in cytosine. This study focuses on trying to determine if the DNA from the vascular endothelial growth factor (VEGF) promoter, which can form an i-motif, can be stabilized with the epigenetic modification to 5- hydroxymethylcytosine in four separate locations on the DNA strand, and to what extent the degree of stabilization depends on the location of the modification. Stability of the i-motif was determined by measuring pKa and melting point (Tm) of each VEGF modification using circular dichroism spectroscopy. The modified samples …


Statistical Analysis Of Arsenic Concentrations In Subsurface Soils At The University Of Mississippi Field Station, David Thomas Webb Jan 2016

Statistical Analysis Of Arsenic Concentrations In Subsurface Soils At The University Of Mississippi Field Station, David Thomas Webb

Honors Theses

The purpose of this investigation is to determine how arsenic concentration varies in soils with respect to soil structures, grain size, soil type, and depth. The investigation was conducted at the University of Mississippi Field Station (UMFS). The UMFS is located in Abbeville, MS and is roughly 700 acres in size. It includes ponds and former agricultural fields, and lies within an internally draining basin. Seven boreholes were drilled using a direct push geoprobe and sampled. The cores obtained from the borings were then cut at one foot intervals, producing a total of 90 soil samples. Each sample was observed …


A Study On The Characterization And Implementation Of Tools For Advanced Ligo, Hunter Gabbard Jan 2016

A Study On The Characterization And Implementation Of Tools For Advanced Ligo, Hunter Gabbard

Honors Theses

The Laser Interferometer Gravitational Wave Observatory (LIGO) is aimed at directly detecting gravitational waves, small perturbations or ripples in the fabric of space-time. Because of their extreme sensitivity, the LIGO detectors are affected by many sources of non-astrophysical noise. In the first part of this thesis we test a pipeline designed for the identification of short-duration noise transients, called Omicron. We first inject simulated noise waveforms in engineering run data from the LIGO detector in Livingston, Louisiana and then determine Omicron efficiency by attempting to recover these injections. In the second part of this thesis, we present a novel method …


Blue Cheese Cosmology: Lensing By Cosmic Strings, Jared Wofford Jan 2016

Blue Cheese Cosmology: Lensing By Cosmic Strings, Jared Wofford

Honors Theses

The light bending effects around cosmic strings in universes with varying rates of expansion are investigated. A relationship between the angular deflection and the expansion rate is found. This is made possible by the Blue Cheese model, which is a generalization to a cylindrical realm of the Swiss Cheese model


Study Of An Active-State Cb1 Receptor Model And Jwh Compound Interactions To Predict New Emerging Synthetic Cannabinoids, Kelsey Leigh Pettus Jan 2016

Study Of An Active-State Cb1 Receptor Model And Jwh Compound Interactions To Predict New Emerging Synthetic Cannabinoids, Kelsey Leigh Pettus

Honors Theses

In recent years, a new class of compounds, called synthetic cannabinoids, have made their appearance in the market as a substitute for illegal marijuana or its constituent natural cannabinoids. These compounds, which are active at the same G- protein coupled receptors (GPCRS) as cannabinoids, are continuing to gain popularity because of the same cannabinoid-like effects they create. Though two cannabinoid receptors have been identified in humans, known as CB1 and CB2, synthetic cannabinoid activity at the CB1 receptor has been the focus of much research regarding synthetic cannabinoid ligand binding. In this study, the structure of the CB1 receptor is …


Conformational Analysis Of A Furan, Thiophene Alternating Π System, Laura Cline Jan 2016

Conformational Analysis Of A Furan, Thiophene Alternating Π System, Laura Cline

Honors Theses

Organic materials with conjugated Ï€-electron networks are increasingly being studied as an alternative to inorganic semiconductors. In order to effectively transport charge as a semiconductor, the organic materials should maintain a planar conformation, exhibit Ï€ conjugation, and be rigid to rotational interconversion. Both furan and thiophene systems have been investigated as potential organic semiconductors but difficulties with solubility, synthesis, and effectiveness hampered these efforts. A novel furan-thiophene hybrid system that exhibits promising semiconducting properties is examined here. Full geometry optimizations and corresponding harmonic vibrational frequency computations were run on a diverse set of potential furan and thiophene oligomer structures using …


The Synthesis Of Substituted Pentadentate Ligand Scaffolds And Their Future Application In Ruthenium-Catalyzed Water Oxidation, Manpreet Singh Jan 2016

The Synthesis Of Substituted Pentadentate Ligand Scaffolds And Their Future Application In Ruthenium-Catalyzed Water Oxidation, Manpreet Singh

Honors Theses

Rising global energy demands coupled with depleting natural resources have led to a strong emphasis on finding new sources of energy that are renewable and which limit the negative impact on the environment. One of the strongest candidates is utilizing solar energy to drive water oxidation to produce hydrogen as a fuel source. In order to do this, a better understanding of the mechanism involved in this process must be revealed. Homogenous molecular catalysts allow mechanistic studies and can be also used in Photoelectrochemical Cells (PECs) and other systems to produce chemical fuels. In this work, the new syntheses of …


The Evolution Of The Sugarcoated American Food Market And The Paradox Of Artificial Sweeteners, Mary Moses Hitt Jan 2016

The Evolution Of The Sugarcoated American Food Market And The Paradox Of Artificial Sweeteners, Mary Moses Hitt

Honors Theses

Living in present-day America makes it hard to imagine an era when sugar was not as inexpensive and readily available as it is now. It is in little colorful packets on restaurant tables, filled to the brim in jars at coffee shops, or mixed into candy products located at the beginning of every cash register. Today, sugar is one of, if not, the most widely consumed food products in the world, but our love for sugar is nothing new. Humans have been experiencing the bliss triggered by sweet-tasting foods since their earliest diets, which included fruits and honey. Our diets …


Paleosol Development And Trace Fossils In The Upper Triassic Cooper Canyon Formation Of The Dockum Group In Andrews County, Texas, Michael Charles Gratzer Jan 2016

Paleosol Development And Trace Fossils In The Upper Triassic Cooper Canyon Formation Of The Dockum Group In Andrews County, Texas, Michael Charles Gratzer

Honors Theses

It is unknown whether a relationship exists between paleosol development and the number of burrows in a paleosol. It is also unknown whether a relationship exists between the number of burrows in a paleosol and the diameters of those burrows. This paper details the methods, results, and conclusions of an investigation of these relationships. I assess the development of several paleosols in a core sample of the Upper Triassic Cooper Canyon Formation of the Dockum Group from well B-133 in Andrews County, Texas, using development scales based on methods from Bown and Kraus (1993) and Abels et al. (2013). I …


Paleolithic Protection In A Western World: A Look Into Preagricultural Nutrition As A Remedy For The Diseases Of Civilization, Emilie R. Caron Jan 2016

Paleolithic Protection In A Western World: A Look Into Preagricultural Nutrition As A Remedy For The Diseases Of Civilization, Emilie R. Caron

Honors Theses

The aim of this investigation is to discover the associations of the Western diet to noncommunicable diseases and to determine if a reversion to a Paleolithic diet will provide treatment and prevention of these diseases. Noncommunicable diseases, otherwise known as Diseases of Civilization, are lifestyle influenced diseases and encompass obesity, diabetes mellitus, cardiovascular disease, and associated cancers. Incidences of these diseases have skyrocketed in the past century and show no signs of decline. Since 1900, the death rates due to heart disease and cancer have risen to account for 47% of total deaths in the United States in 2010. (Tippett, …


Multidimensional Motion Capture Using Doppler Ultrasound, Forrest Nolan Gamble Jan 2016

Multidimensional Motion Capture Using Doppler Ultrasound, Forrest Nolan Gamble

Honors Theses

Ultrasonic waves are used to measure the velocity of a target object by measuring the Doppler shift of the reflected waves. In this work, ultrasonic Doppler Sonar (UDS) was used to measure the velocity of objects, including a pendulum and a battery on a turntable. The investigation focused on developing a method to measure motion in two and three dimensions, for applications in gait analysis and sports motion capture. By using multiple ultrasonic transducers and novel data processing techniques, the UDS captured motion in two and three dimensions. In order to test the accuracy of the velocity and position measurements, …


On Topological Indices And Domination Numbers Of Graphs, Shaohui Wang Jan 2016

On Topological Indices And Domination Numbers Of Graphs, Shaohui Wang

Electronic Theses and Dissertations

Topological indices and dominating problems are popular topics in Graph Theory. There are various topological indices such as degree-based topological indices, distance-based topological indices and counting related topological indices et al. These topological indices correlate certain physicochemical properties such as boiling point, stability of chemical compounds. The concepts of domination number and independent domination number, introduced from the mid-1860s, are very fundamental in Graph Theory. In this dissertation, we provide new theoretical results on these two topics. We study k-trees and cactus graphs with the sharp upper and lower bounds of the degree-based topological indices(Multiplicative Zagreb indices). The extremal cacti …


Gas Exchange Of Hg Over Wetlands, Effect Of Biochar And Activated Carbon On Hg Emissions From Soil, And Seasonal Concentrations Of Hg In Rain, Divya Nallamothu Jan 2016

Gas Exchange Of Hg Over Wetlands, Effect Of Biochar And Activated Carbon On Hg Emissions From Soil, And Seasonal Concentrations Of Hg In Rain, Divya Nallamothu

Electronic Theses and Dissertations

Mercury (Hg) is a global pollutant with human-health and ecological impacts. Gaseous Hg exchange between the atmosphere and aquatic or terrestrial surfaces serves as an important, but not well understood, route for Hg to enter and exit ecosystems. To better understand the role of gaseous Hg exchange in the biogeochemical cycling of Hg, we investigated Hg0 fluxes over natural wetlands (Sky Lake) and artificial wetlands (UM Field Station) using a dynamic flux chamber and an Hg vapor analyzer based on atomic fluorescence (Chapter 1). We also examined the effect of activated carbon and biochar on Hg emissions from soils for …