Digital Commons Network^™

Structural Analysis Of Bulky Thiolate-Protected Gold Nanomolecules, David Walton Crasto

Electronic Theses and Dissertations

Routine preparation of thiolate-protected gold nanomolecules involves, most commonly, straight-chain organic thiolate ligands for which the sulfhydryl `head' group is bound to a primary carbon atom. The primary connectivity of these sulfur atoms, such as for the case of n-hexanethiol and phenylethanethiol, allows for even packing, and the relative ease of formation of gold-thiolate oligomers about the surface monolayer in the formation of Au-SR bonds. Moreover, these straight-chain ligands routinely support the formation of an icosahedron-based series of core-size gold nanomolecules. Within this series of nanoparticles, Au25(SR)18 and Au38(SR)24 are among the most commonly studied core-sizes; Au25(SR)18 is situated upon …

Measurements Of Fluvial Sediments Using A Single-Frequency Acoustic Attenuation System, Thomas Alexander Kajdan

Electronic Theses and Dissertations

Suspended sediments are a global-scale pollutant that threaten the integrity of our waterways and pose an environmental threat to many aquatic ecosystems. Innovative techniques are required to continuously monitor this pollutant. Ultrasonic acoustic measurements have the potential to improve the temporal resolution of fluvial sediment data. This work investigates the use of a prototype field grade single-frequency acoustic attenuation system that was developed at the National Center for Physical Acoustics (NCPA), located at the University of Mississippi. This field-deployable unit consists of two 20 MHz immersion transducers that are aligned in a "pitch-catch" configuration at a fixed distance of 18 …

Random Forests Based Rule Learning And Feature Elimination, Sheng Liu

Electronic Theses and Dissertations

Much research combines data from multiple sources in an effort to understand the underlying problems. It is important to find and interpret the most important information from these sources. Thus it will be beneficial to have an effective algorithm that can simultaneously extract decision rules and select critical features for good interpretation while preserving the prediction performance. We propose an efficient approach, combining rule extraction and feature elimination, based on 1-norm regularized random forests. This approach simultaneously extracts a small number of rules generated by random forests and selects important features. To evaluate this approach, we have applied it to …

The Relationship Between Teacher Perception Of Principals' Leadership Behaviors And Student Achievement, Monte Damon Ladner

Electronic Theses and Dissertations

The purpose of this research study was to determine whether a relationship exists between student achievement, as measured by school Quality of Distribution Index score, and school leadership based on staff perceptions of school leadership, as measured by the Survey of Supervisory Behavior. The leadership of seven schools was assessed by staff members in five different sub scales of leadership domains: human relations, trust/decision making, instructional leadership, control, and conflict. The seven schools sampled were comprised of four rural or county schools and three city schools. The subjects for this study were principals of standalone schools containing grades five, six, …

Optimized Image Compressed Sensing And Transmission Through Wireless Channels, Saheed Olanigan

Electronic Theses and Dissertations

This thesis examines the robust behavior of quantized compressed sensing measurements during transmission through an additive white gaussian noise wireless channel. The poor rate-distortion performance that accompanies compressed sensing after applying quantization has led to several works in quantized compressed sensing. However, most of these works have less consideration of the effect of transmission channel on the resulting bit stream of the quantized compressed sensing measurements. For an additive white gaussian noise wireless channel model, the quantizer and bit energy signal-to-noise ratio determines the degree of the channel effect. This thesis explores the effect of quantization and channel noise during …

Ramsey Theory Using Matroid Minors, Dixie Smith Horne

Electronic Theses and Dissertations

This thesis considers a Ramsey Theory question for graphs and regular matroids. Specifically, how many elements N are required in a 3-connected graphic or regular matroid to force the existence of certain specified minors in that matroid? This question cannot be answered for an arbitrary collection of specified minors. However, there are results from the literature for which the number N exists for certain collections of minors. We first encode totally unimodular matrix representations of certain matroids. We use the computer program MACEK to investigate this question for certain classes of specified minors.

The Characterization Of Graphs With Small Bicycle Spectrum, Bette Catherine Putnam

Electronic Theses and Dissertations

Matroids designs are defined to be matroids in which the hyperplanes all have the same size. The dual of a matroid design is a matroid with all circuits of the same size, called a dual matroid design. The connected bicircular dual matroid designs have been characterized previously. In addition, these results have been extended to connected bicircular matroids with circuits of two sizes in the case that the associated graph is a subdivision of a 3-connected graph. In this dissertation, we will use a graph theoretic approach to discuss the characterizations of bicircular matroids with circuits of two and three …

Moments Of Products Of L-Functions, Caroline Laroche Turnage-Butterbaugh

Electronic Theses and Dissertations

We first consider questions on the distribution of the primes. Using the recent advancement towards the Prime k-tuple Conjecture by Maynard and Tao, we show how to produce infinitely many strings of consecutive primes satisfying specified congruence conditions. We answer an old question of Erdös and Turán by producing strings of consecutive primes whose successive gaps form an increasing (respectively decreasing) sequence. We also show that such strings exist whose successive gaps follow a certain divisibility pattern. Finally, for any coprime integers a and D ≥ 1, we refine a theorem of D. Shiu and find strings of consecutive primes …

Emplacement Of Pleistocene Basalt Flows Near Mccoy, Colorado, Andrea Bowen

Electronic Theses and Dissertations

No abstract provided.

An Evaluation Of Perceived Safety Of Free Software: The Brafs Model, Will Pepper

Electronic Theses and Dissertations

This dissertation explores the perceived safety of free software and its relationship with the intention to use this technology in a business setting. The newly created construct of perceived safety is developed out of the theory of planned behavior. It is researched, scrutinized, and refined according to academic guidelines and two different environmental settings. The constructs that impact perceived safety and its relationship with intention to use consist of technology perceived risk, technology trusting beliefs, expected financial utility, and perceived adverse impact on professional reputation. Each construct consists of multiple operationalized elements. To explore this empirically, beneficial and risk measurements …

Elementary Teachers' Use Of And Comfort Level Teaching Music, Jennifer Elizabeth Peck Campbell

Electronic Theses and Dissertations

No abstract provided.

Academic Hazing In Music Education, Cameron Whitworth Jenkins

Electronic Theses and Dissertations

Abstract: academic hazing in this context is defined as the academic misuse of new or prospective graduate students in music education. Academic hazing can also refer to senior faculty who haze junior faculty during the years prior to tenure. This study was designed in two parts to examine academic hazing in graduate music education programs. First, twelve (n=12) faculty academic advisors, each serving as director of music education at their respective four-year comprehensive universities, were intervievia electronic mail. Then, fourteen (n=14) current graduate students in music education were intervieto gain the perspectives of their graduate experience. Each student was intervieby …

Solubility Enhancement Via Melt Extrusion: Drug-Polymer Solubility, Physicochemical Characterization And Quality By Design, Ketaki Patwardhan

Electronic Theses and Dissertations

Many new drugs developed face oral delivery challenges and absorption due to poor biopharmaceutical properties. Formation of solid dispersions is a very widely applied technique for solubility enhancement of water insoluble drugs. In order to form stable solid dispersions it is important to select appropriate excipients that will maintain the drug in its amorphous form for an extended period of time. Selection of appropriate excipients is critical during the development of stable amorphous solid dispersions. The solubility parameter concept has been explored for theoretically identifying the excipients that will be suitable based on the structure of the active. In this …

Fluctuations In Resistivity In The Tuscaloosa Marine Shale, Southwest Mississippi And Southeast Louisiana, Thomas Hetherington Story

Electronic Theses and Dissertations

The Tuscaloosa Marine Shale in southwest Mississippi and Southeast Louisiana's Florida Parishes has become an unconventional target for the exploration and production of oil. Spurred by early estimates of over 7 billion barrels of oil in place, the target region for this production is the basal portion of the shale where a continuous increase in resistivity greater than 5 Ohmm can be observed. This increase was originally attributed solely to the generation of hydrocarbons from the organic matter contained within the shale, with the presence of the oil and gas impeding the flow of electrons through what would normally be …

Parametric Scramjet Analysis, Jongseong Choi

Electronic Theses and Dissertations

The performance of a hypersonic flight vehicle will depend on existing materials and fuels; this work presents the performance of the ideal scramjet engine for three different combustion chamber materials and three different candidate fuels. Engine performance is explored by parametric cycle analysis for the ideal scramjet as a function of material maximum service temperature and the lower heating value of jet engine fuels. The thermodynamic analysis is based on the Brayton cycle as similarly employed in describing the performance of the ramjet, turbojet, and fanjet ideal engines. The objective of this work is to explore material operating temperatures and …

Synthesis, Characterization And Electrochemical Properties Of Gold Nanomolecules, Vijay Bhaskar Reddy Jupally

Electronic Theses and Dissertations

Chapter 1 gives a brief introduction to the field of gold nanomolecules. Various synthetic protocols and analytical techniques used through out this dissertation are discussed in detail. Size dependent properties of the gold nanomolecules are described. The structure of gold nanomolecules is explained based on the crystal structure of Au25(SCH2CH2Ph)18. The theoretical basis for the stability of the gold nanomolecules is explained using the super atom complex model and geometric parameters. Chapter 2 includes ligand exchange experiments on gold nanomolecules. Ligand exchange experiments are used to modify the monolayer of nanomolecules after synthesis. Ligand exchange reactions are monitored by mass …

Neurocognitive Outcomes In Children Experiencing Seizures During Treatment For Acute Lymphoblastic Leukemia, Stephanie L. Nassar

Electronic Theses and Dissertations

There is a growing literature for cognitive late effects among childhood cancer survivors, yet little empirical information is known regarding specific neurocognitive outcomes of children who experience seizures while treated for acute lymphoblastic leukemia. This study examined prevalence of on-protocol seizures, seizure risk factors, and neurocognitive change in children with therapy-related seizures in comparison to the normative sample and a matched cohort of children without on-protocol seizures. Participants included children enrolled on the St. Jude frontline leukemia treatment protocol, Total Therapy 15 (TOTXV) - the first systematic investigation of intensified chemotherapy agents plus optimal intrathecal therapy without irradiation. Out of …

Group Velocity Of Acoustic Waves In Plates Of Electronic Materials, Saminda Adikaram

Electronic Theses and Dissertations

In this study the propagation and dispersion characteristics of plate acoustic waves (PAW) in electronic materials are investigated experimentally. Plate acoustic waves are elastic waves that travel along a plate with thickness comparable to the wavelength of the waves. Lamb waves, a type of plate acoustic wave, have particle motion in the direction of propagation and normal to the plate. Unlike an infinite medium, plates support two sets of Lamb wave modes (symmetric and anti-symmetric) with unique velocities which depend on the relationship between the wavelength and the thickness of the plate. Out of this, two zero order modes (so …

Increasing Self-Efficacy And Quality Lesson Planning Using Lesson-Study With Elementary Preservice Teachers, Elizabeth Ann Mitchell

Electronic Theses and Dissertations

This qualitative, quasi-experimental study examined if lesson-study could be a successful approach in improving lesson plan quality and increasing self-efficacy levels toward teaching science at the preservice elementary teacher level in North Mississippi. Lesson-Study can be defined as a cycle of instructional improvement in which small groups work together to design and teach a lesson, revising again as needed over the course of a semester. This study described the experiences of two sections of preservice teachers enrolled in a science methods course as they engaged in lesson-study at a comprehensive university in Northeast Mississippi. One section of the class served …

Characterizing Non-Covalent Interactions And Peptide Bond Formation With Electronic Structure Theory, Eric Van Dornshuld

Electronic Theses and Dissertations

The development and application of quantum mechanics has exploded in the past century. The rules of classical mechanics were found to be completely insufficient when applied to a universe that operates on the scale of atomic and subatomic particles. The advancement of quantum theory and computer technology has driven quantum mechanical analyses toward routine in the chemist's laboratory. Chapter 1 briefly outlines some comfailures of classical mechanics from a historical standpoint. Chapter 2 provides a mathematical overview to quantum chemistry including a brief presentation of the analytic solutions to the schrã¶dinger equation for some model systems. Chapter 3 and chapter …

An Analysis Of Two-Year College Fundraising Practices, Luke Joel Howard

Electronic Theses and Dissertations

Abstract: this study sought to discover information about the types of fundraising methods being used in community college resource development, determine what methods are most effective for successful development practices, and inform community college development officers of these methods. Specifically, this study addressed the following question: are there statistically significant relationships between two-year college size, fundraising method(s), and the amount of funds raised? Descriptive statistics were obtained, and two-way chi-square analysis was used to illustrate the comparisons between the categorical variables in all hypotheses. Only one hypothesis was rejected based on a computed chi-square (χ2 = 22.507), which exceeded the …

Location, Location: Factors Influencing Greenhouse Gas Fluxes From The Mississippi Delta Agricultural Region, Michael P. Keating

Electronic Theses and Dissertations

Methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) fluxes from agricultural landscapes may contribute significantly to regional greenhouse gas budgets due to stimulation of soil microbial activity through fertilizer application. Few studies have made measurements of CH4, N2O, and CO2 from the dominant landscape features of the agricultural landscape: farmland, riparian zone, and wetland habitat. This study assessed gas emission variability from the Mississippi Delta agricultural landscape and explored the effects of hydrology and hydrophytic vegetation on gas emissions.

Gas collection chambers were utilized to make gas measurements from soybean and corn farmland, vegetated riparian buffer, and two vegetated …

Customer Tolerance In Community Pharmacy, Philip Everett Schwab

Electronic Theses and Dissertations

Customers can have an existing relationship with a service provider where they are not satisfied with the services they receive, yet they continue to patronize the service provider. Why does this happen? Why do these customers remain as patrons of service providers that do not meet expectations and that leave these customers with low satisfaction. This dissertation presents the concept of tolerance to explain the retention of customers who are not satisfied with a service provider. Specifically, this dissertation examined the concept of customer tolerance in community pharmacy. Tolerance is an important concept for consideration because regardless of good intentions …

Cosmological And Astrophysical Tests Of Modified Gravity, Caixia Gao

Electronic Theses and Dissertations

Three alternative theories to general relativity will be studied. The aim is to test these theories by applying them to astronomical objects or the cosmological background. The first one is unimodular relativity. The cosmological perturbation theory of this model is studied and the predictions on temperature fluctuations of the cmb are found. The second one is drgt massive gravity. In this theory a charged black hole solution is found and compared to those in gr, folloby constraints on the parameter space. The third one is a general massive gravity theory which shares the same background equation with the massless case …

Non-Hydrostatic Models For Wave Propagation, Breaking, And Run-Up, Zhangping Wei

Electronic Theses and Dissertations

This dissertation develops a series of non-hydrostatic pressure wave models based on the finite element free surface flow model, CCHE2D, for simulating propagation, breaking, and run-up of coastal wave processes. The first non-hydrostatic formulation presented in this dissertation directly introduces a non-hydrostatic pressure module into CCHE2D. An edge-based pressure allocation method is implemented, and a depth-integrated vertical momentum equation is introduced. The depth-integrated horizontal momentum equations are solved for a provisional velocity field, and then the non-hydrostatic pressure is obtained by satisfying the divergence-free velocity field condition, subsequently the velocity field is corrected by the non-hydrostatic pressure. Finally the free …

Segmentation And Spatial Depth Ridge Detection Of Unorganized Point Cloud Data, James Clark Church

Electronic Theses and Dissertations

Visual 3D data are of interest to a number of fields: medical professionals, game designers, graphic designers, and (in the interest of this paper) ichthyologists interested in the taxonomy of fish. Since the release of the Kinect for the Microsoft XBox, game designers have been interested in using the 3D data returned by the device to understand human movement and translate that movement into an interface with which to interact with game systems. In the medical field, researchers must use computer vision tools to navigate through the data found in CT scans and MRI scans. These tools must segment images …

Optimization Of Wind Fence Enclosures For Infrasonic Wind Noise Reduction, Johnpaul Russell Abbott

Electronic Theses and Dissertations

A large porous wind barrier enclosure has been built and tested to optimize wind noise reduction at infrasonic frequencies between 0.01-10 Hz in order to develop a technology that is simple, cost effective, and improves upon the limitations of pipe and porous hose arrays. The effects of varying the fence's porosity, modifying its top condition and bottom gap, doubling the height and diameter, and adding a secondary wind barrier were investigated. A simple mathematical model which estimates the wind noise measured at the center of the enclosure was derived based on the measured turbulence and velocity profiles measure outside the …

Anchoring The Potential Energy Surfaces Of Homogenous And Heterogenous Dimers Of Formaldehyde And Thiofomaldehyde, Christina M. Holy

Honors Theses

This work characterizes five stationary points of the formaldehyde dimer, (CH2O)2, two of which are minima, seven newly-identified stationary points of the formaldehyde/thioformaldehyde (mixed) dimer, CH2O/CH2S, four of which are minima, and five newly-identified stationary points of the thioformaldehyde dimer, (CH2S)2 , three of which are minima. Full geometry optimizations and corresponding harmonic vibrational frequencies were performed on CH2O and CH2S as well as each of the dimer configurations (Figures 3-5). The computations were carried out with second order Møller-Plesset perturbation theory (MP2), with the heavy-auc-cc-pVTZ (haTZ) basis set. Additionally, thirteen density functional theory methods were employed: B3LYP, B3LYP-D3, B3LYP-D3(BJ), …

Implementation Of A Visualizer For Web Request Data Generated By An Internet Information Services Server, Daniel J. Garrett

Honors Theses

I was tasked by Graham Green at FNC, Inc. to design a web tool that is capable of visualizing log data that is produced by FNC's many servers. These logs contain data that will warn Graham about web pages that are failing, servers that are experiencing heavy loads, and sundry other pieces of information, but the data is pure text, and each server has thousands of logs. A visual tool is needed to display necessary information about the data. Rather than make a graph for each individual purpose that might be needed, I built visualization tools that are customizable for …

An Investigation Into Polyiodination Of Activated Benzene Derivatives With Electrophilic Aromatic Substitution Reactions, Dakota Gilbert

Honors Theses

The aim of this research is to investigate the periodination of benzene derivatives that are activated towards electrophilic aromatic substitution. In this research, a successful electrophilic aromatic substitution reaction was completed with procedures that used iodine with silver sulfate as an activating agent in the reaction mixture. The ball-milling technique with N-iodosuccinnimide as the iodinating reagent was also explored. Only one iodine was added onto 4-iodoanisole as the activated benzene derivative. When 2,4-dichloroanisole was the substrate, a small amount of diiodo product accompanied the monoiodo product, but no triiodo (periodinated) product was observed. Nonetheless, the trials of this research give …