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Computational Models To Predict The Inhibition Of Cytochrome P450 3a4 By Selected Natural Compounds, Sushma Thotakura

Theses and Dissertations

Cytochrome P450 3A4 (CYP3A4) plays a pivotal role in the metabolism of xenobiotics. Methylenedioxobenzene containing natural products have been shown to inhibit CYP3A4. Given that these compounds are widely distributed in nature there is a strong potential for drug interaction with many plants used for dietary or medicinal purposes. In this research we have developed two different computational models (Comparative Molecular Field Model and Artificial Neural Network Model) to assist in the identification of potentially strong inhibitors that could be further studied for potential inhibitory effects. These models were used to screen for the CYP3A4 inhibitory effects of 100 naturally …

Differentiating Between Women In Hard And Soft Science And Engineering Disciplines, Amanda Gail Camp

Theses and Dissertations

The intent of the study was to investigate how women in hard (engineering, mathematics, computer science, physical science) and soft (social, psychological, life sciences) sciences differ from each other among a set of variables known to influence educational attainment and to evaluate how well Weidman's undergraduate socialization model explains higher education's influence on women in science and engineering fields. Using the Beginning Postsecondary Students Longitudinal Study (1996-2001), descriptive discriminant analysis and multivariate analysis of variance were used to identify differences among the women, and structural equation modeling was used to evaluate Weidman's model. Results indicated that women who went into …

Evaluation And Characterization Of Some Biologically Active Coumarin Derived Sulfonamides, Harish Gosike

Theses and Dissertations

Sulfonamide drugs discovered in the 1930's were the first effective chemotherapeutic agents to be employed for the prevention and cure of bacterial infections in humans. Bacterial resistance to these drugs over the years has led to the development of new variety of sulfonamide derivatives. Recently Chohan et al. synthesized a series of coumarin derived sulfonamides and their chemical structures have been established. In this report, we present some microbiological studies to establish the antibacterial characters of these compounds. In order to establish their chemical structure-biological activity relationship, electrochemical and spectroscopic studies have been conducted. Antibacterial studies conducted on these compounds …

Identification Of Potential Organic Contributors In Carbonaceous Aerosols: Enhanced Uv Absorption Spectra, Anand Mangu

Theses and Dissertations

Direct aerosol climate effects include light scattering and absorption that present the largest uncertainties in the assessment of radiative forcing. To estimate the overall effect of aerosols on climate the relative amounts of scattering and absorption must be known. Determination of aerosol UV-absorption spectra is the primary focus of this thesis research. Aerosol samples were collected in Mexico City in 2003 and 2006 as a part of Mexico City Metropolitan Area field study and also at Little Rock. UV-visible absorption spectra of these aerosol samples have been obtained by using an integrating sphere coupled to a UV-visible spectrometer and compared …

Load Distribution And Channel Assignment In Ieee 802.11 Wireless Local Area Networks, Mohamad Haidar

Theses and Dissertations

Recent growth in Wireless Local Area Network (WLAN) deployment has generated considerable interest in load management and channel assignment among network designers. WLAN has become a major component of the modern telecommunication infrastructure. Load management and Channel assignment are among the critical aspects that face WLAN deployments. Well planned WLAN service environments require a network designed to provide not only radio coverage but also better load distribution and less interference across the service area, which in turn improves the Quality of Service (QoS). In this dissertation, a novel approach to the WLAN load distribution and channel assignment is proposed that …

Mining Frequent Patterns From Sequences: Theory, Algorithm, Implementation, And Performance, Markus Petteri Turkia

Theses and Dissertations

Mining frequent patterns from sequences is an important data mining problem which has direct applications in many areas. In this thesis, we make three contributions to the state-of-the-art of the sequential frequent pattern mining. First of all, we propose a fast pattern-growth mining algorithm using a novel sequence database representation called First-Occurrence Linked WAP-tree (FLWAP-tree). The pattern-growth mining algorithm using the Pre-Order Linked WAP-tree (PLWAP-tree) was reported in the literature to be faster than other algorithms. We show that our pattern-growth using our FLWAP-tree outperforms the PLWAP-tree mining significantly and consistently. Secondly, we extend the pattern-growth algorithm with partial enumeration …

Synthesis And Characterization Of Highly Conductive Polypyrrole And Polypyrrole/Lignosulfonate/Graphite Composites, Aopeau Imvittaya

Theses and Dissertations

Polypyrrole (PPy) is one of the conductive polymers frequently used in commercial applications, mainly due to its long-term stability and the possibility of forming homopolymers or composites with optimal properties. Polypyrroles were prepared by the chemical polymerization of pyrrole using various methods. The effects of several parameters such as oxidant, dopant type, additives and reaction conditions on the properties of PPy were investigated. In addition, PPy/graphite composites were prepared because graphite is highly conductive and effectively incorporated into the polymer matrix during the polymerization. The amount of graphite in the composite was varied to determine the maximimum conductivity achievable in …

The Abc's Of Early Intervention: Assessing The Arkansas Better Chance For School Success Pre -School Program, Lisa Walker Todd

Theses and Dissertations

Early intervention programs have long been associated with increased cognitive benefits for disadvantaged poverty children. The Arkansas Better Chance for School Success Pre-school Program (ABCSS) was implemented in select counties in Arkansas as an early intervention strategy for Arkansas' poverty children. The core rationale behind the implementation of the Arkansas Better Chance for School Success Pre-school Program was the belief that it is much easier not to be left behind if you do not start behind. The study assessed the Arkansas Better Chance for School Success Pre-school Program on the impact of sustained benefits on third grade children who previously …

The Relationship Between Grade Span Configuration And Academic Achievement, Mary Jane Dove

Theses and Dissertations

NCLB demands academic achievement in return for federal funding. Many Arkansas schools are having difficulty meeting these academic achievement goals. The purpose of the study was to explore the relationship between grade span configuration and academic achievement as measured by the Arkansas Benchmark Examination, which is the approved NCLB criterion-referenced annual assessment. The population identified was all schools in Arkansas containing grade 6. A purposive sample was drawn containing three different grade span groups according to the year of transition of 6th grade students ( N = 281). Data collection involved gathering results of the Benchmark Exam in mathematics and …

Nova Quarterly: The University Of Texas At El Paso, The University Of Texas At El Paso University Communications

NOVA

Winter 2007, Vol. 45, No. 4; No. 172

What Explains Credit Default Swaps Bid-Ask Spread?, Yaru Chen

Dissertations and Theses Collection (Open Access)

The pace at which the Credit default swaps (CDS) has been growing since its inception topped all projections. Despite the rapid growth, there is still room for enhancement of liquidity in the CDS market. Asymmetric information is another concern of investors in CDS market, however, some literature addressed that it may not be as serious as regarded. Bid-ask spreads is commonly used as a proxy of both liquidity and asymmetric information. Our empirical study confirms that CDS bid-ask spread has explanatory power to CDS premium. We then investigate the liquidity component in CDS bid-ask spreads. We use the bond age, …

Evaluating Predictive Performance Of Value-At-Risk Models In Chinese Stock Markets, Jianshe Ou

Lingnan Theses

Risk can be defined as the volatility of unexpected outcomes, generally for values of assets and liabilities. Financial risk, risk refer to possible losses in financial markets, includes markets risk, credit risk, liquidity risk, operational risk, and legal risk. This MPhil thesis is specializing on market risk, which involves the uncertainty of earnings or losses resulting from changes in market conditions such as asset prices, interest rates, and market liquidity.

The primary tool to evaluate market risk is VaR that is a method of assessing risk through standard statistical techniques. VaR is defined a measure for the worst expected loss …

Singlet Oxygen Generation Using New Fluorene-Based Photosensitizers Under One- And Two-Photon Excitation, Stephen James Andrasik

Electronic Theses and Dissertations

Molecular oxygen in its lowest electronically excited state plays an important roll in the field of chemistry. This excited state is often referred to as singlet oxygen and can be generated in a photosensitized process under one- or two-photon excitation of a photosensitizer. It is particularly useful in the field of photodynamic cancer therapy (PDT) where singlet oxygen formation can be used to destroy cancerous tumors. The use of two-photon activated photosensitizers possesses great potential in the field of PDT since near-IR light is used to activate the sensitizer, resulting in deeper penetration of light into biological tissue, less photobleaching …

The Effects Of Reciprocal Teaching Strategies On Students' Comprehension Of A Seventh Grade Life Science Text, Brooke Bess

Electronic Theses and Dissertations

This action research study was conducted with 7th grade life science students at a public middle school in central Florida. The author used Reciprocal Teaching (RT) as described by Annemarie Palincsar and Anne Brown (1984) to examine changes in student comprehension when reading their life science textbook and changes in how the students used the predicting, questioning, and summarizing strategies. The RT strategies ask students to employ 4 strategies: predict what they will read, generate questions about what was read, clarify any ideas that were not understood in the reading, and summarize the main idea of the reading. Students were …

Two-Dimensional Guided Mode Resonant Structures For Spectral Filtering Applications, Sakoolkan Boonruang

Electronic Theses and Dissertations

Guided mode resonant (GMR) structures are optical devices that consist of a planar waveguide with a periodic structure either imbedded in or on the surface of the structure. The resonance anomaly in GMR structures has many applications as dielectric mirrors, tunable devices, sensors,and narrow spectral band reflection filters. A desirable response from a resonant grating filter normally includes a nearly 100% narrowband resonant spectral reflection (transmission), and a broad angular acceptance at either normal incidence or an oblique angle of incidence. This dissertation is a detailed study of the unique nature of the resonance anomaly in GMR structures with two-dimensional …

Discrimination Of Forensic Trace Evidence Using Laser Induced Breakdown Spectroscopy, Candice Bridge

Electronic Theses and Dissertations

Elemental analysis in forensic laboratories can be tedious and many trace evidence items are not analyzed to determine their elemental composition. Presently, scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDS) is the primary analytical tool for determining the elemental composition of trace evidence items. However, due to the time it takes to obtain the required vacuum and the limited number of samples that can be analyzed at any one time, SEM-EDS can be impractical for a high volume of evidence items. An alternative instrument that can be used for this type of analysis is laser ablation inductively coupled plasma mass spectrometry …

Raman Spectroscopic Study Of Single Red Blood Cells Infected By The Malaria Parasite Plasmodium Falciparum, William Carter

Electronic Theses and Dissertations

Raman micro-spectroscopy provides a non-destructive probe with potential applications as a diagnostic tool for cellular disorders. This study presents micro-Raman spectra of live erythrocytes infected with a malaria parasite and investigates the potential of this probe to monitor molecular changes which occur during differentiation of the parasite inside the cell. At an excitation wavelength of 633 nm the spectral bands are dominated by hemoglobin vibrations yielding information the on structure and spin state of the heme moiety. It also demonstrates the novel use of silica capillaries as a viable method for studying the erythrocytes in an environment that is much …

Scanning Fabry-Perot Spectrometer For Terahertz And Gigahertz Spectroscopy Using Dielectric Bragg Mirrors, Justin Cleary

Electronic Theses and Dissertations

A scanning Fabry-Perot transmission filter composed of a pair of dielectric mirrors has been demonstrated at millimeter and sub-millimeter wavelengths. The mirrors are formed by alternating quarter-wave optical thicknesses of silicon and air in the usual Bragg configuration. Detailed theoretical considerations are presented for determining the optimum design including factors that affect achievable finesse. Fundamental loss by lattice and free carrier absorption are considered. High resistivity in the silicon layers was found important for achieving high transmittance and finesse, especially at the longer wavelengths. Also considered are technological factors such as surface roughness, bowing, and misalignment for various proposed manufacturing …

Two-Photon 3d Optical Data Storage Via Fluorescence Modulation Of Fluorene Dyes By Photochromic Diarylethenes, Claudia Corredor

Electronic Theses and Dissertations

Three-dimensional (3D) optical data storage based on two-photon processes provides highly confined excitation in a recording medium and a mechanism for writing and reading data with less cross talk between multiple memory layers, due to the quadratic dependence of two photon absorption (2PA) on the incident light intensity. The capacity for highly confined excitation and intrinsic 3D resolution affords immense information storage capacity (up to 1012 bits/cm3). Recently, the use of photochromic materials for 3D memory has received intense interest because of several major advantages over current optical systems, including their erasable/rewritable capability, high resolution, and high sensitivity. This work …

Frequency Distribution Of Pyroxene Types And A Method To Separate The Composition Of Multiple Pyroxenes In A Sample, Jimmy Allen Davis

Electronic Theses and Dissertations

Determining mafic mineral composition of asteroid bodies is a topic reviewed by M.J. Gaffey et al. (2002). The iterative procedure discussed can be implemented as an algorithm, and such efforts revealed weaknesses that are examined in this work. We seek to illustrate the limits of this method and graphically determine its predictions. There are boundaries in the formulae given where the equations break down. In ranges where mafic mixtures are predicted, a method is illustrated that allows a decoupling of these mixtures into the constituents.

Faculty Perceptions Of Alignment Ofadministrative Practices With A University Missionutilizing A Hospitality Model, Duncan Dickson

Electronic Theses and Dissertations

The purpose of this study was to explore the perceptions of a university's faculty as to how the strategies, staffing policies, and systems procedures were aligned with the mission statement. Differences in perceptions were examined by college affiliation, rank, primary teaching assignment and gender. Data were analyzed to determine if there were correlations between faculty members' perceptions of alignment of the university's mission statement with administration's actions, policies, and procedures and their level of organizational commitment, job satisfaction, and overall satisfaction with their job and the organization The population for this study was comprised initially of 1363 teaching faculty members …

Central Florida High School Principals' Perceptions Of The Florida School Indicators Report, William Gaught

Electronic Theses and Dissertations

The purpose of this study was to identify the perceptions that central Florida public high school principals had regarding the Florida School Indicators Report (FSIR) and its usefulness. The FSIR, published by the Florida Education, was designed to be a comprehensive, single source document for parents, lawmakers, and school administrators to compare key performance indicators to similar schools or districts state wide. It provided information on 74 different indicators of school or district performance. A total of 70 public high school principals from 13 central Florida school districts responded to a postal survey and provided their perceptions regarding the importance …

Spectroscopic Studies Of Laser Plasmas For Euv Sources, Simi A. George

Electronic Theses and Dissertations

With the availability of high reflectivity multilayer mirrors and zone plate lenses, the EUV region (5nm - 40nm) of the electromagnetic spectrum is currently being explored for applications of nanoscale printing and imaging. Advances made in this area have consequences for many areas of science. Research for producing a compact, bright EUV source for laboratory use has gained momentum in recent years. For this study, EUV radiation is produced by irradiating target materials using a focused laser beam. Focused laser beam ionizes the target to create a hot, dense, pulsed plasma source, where emission is a result of the relaxation …

Physically-Based Visualization Of Residential Building Damage Process In Hurricane, Dezhi Liao

Electronic Theses and Dissertations

This research provides realistic techniques to visualize the process of damage to residential building caused by hurricane force winds. Three methods are implemented to make the visualization useful for educating the public about mitigation measures for their homes. First, the underline physics uses Quick Collision Response Calculation. This is an iterative method, which can tune the accuracy and the performance to calculate collision response between building components. Secondly, the damage process is designed as a Time-scalable Process. By attaching a damage time tag for each building component, the visualization process is treated as a geometry animation allowing users to navigate …

Real-Time Tree Simulation Using Verlet Integration, Bobak Manavi

Electronic Theses and Dissertations

One of the most important challenges in real-time simulation of large trees and vegetation is the vast number of calculations required to simulate the interactions between all the branches in the tree when external forces are applied to it. This paper will propose the use of algorithms employed by applications like cloth and soft body simulations, where objects can be represented by a finite system of particles connected via spring-like constraints, for the structural representation and manipulation of trees in real-time. We will then derive and show the use of Verlet integration and the constraint configuration used for simulating trees …

Perceptions Of The Emotional/Behavioral Disability Label On Educators' Referral And Placement Decisions To Gifted And Talent, Charissa Marrah

Electronic Theses and Dissertations

Socio-culturally diverse students with disabilities are underrepresented in gifted and talented programs. This study investigated the differences in educators' referral and placement decisions based on a students' disability label, socio-economic status (SES), and ethnicity. Two hundred and eighty five educators' (classroom teachers, school counselors, school psychologists, and school social workers) across a Florida school district participated in the study. Educators' were randomly assigned to treatment and control case vignettes that described a student with emotional/behavioral disabled (EBD) and gifted characteristics. Treatment case vignettes explicitly stated the students' disability label, socio-economic status, and ethnicity. Control case vignettes described of the student …

Effect Of Inner Scale Atmospheric Spectrum Models On Scintillation In All Optical Turbulence Regimes, Kenneth Mayer

Electronic Theses and Dissertations

Experimental studies have shown that a "bump" occurs in the atmospheric spectrum just prior to turbulence cell dissipation.1,3,4 In weak optical turbulence, this bump affects calculated scintillation. The purpose of this thesis was to determine if a "non-bump" atmospheric power spectrum can be used to model scintillation for plane waves and spherical waves in moderate to strong optical turbulence regimes. Scintillation expressions were developed from an "effective" von Karman spectrum using an approach similar to that used by Andrews et al.8,14,15 in developing expressions from an "effective" modified (bump) spectrum. The effective spectrum extends the Rytov approximation into all optical …

Direct And Indirect Effects Of Selected Factors On School Grades In Public High Schools In The State Of Florida, Joseph Miller

Electronic Theses and Dissertations

The purpose of this study was to examine the direct and indirect effects of selected factors on school grades in public high schools in the state of Florida. A sample of 316 public high schools was created using data obtained from the Florida Education and the Florida High School Athletic Association. The selected factors that were chosen to be measured in the study were: minority percentage as measured by the proportion of minority students in relation to the total student body at a given school, socio economic status percentage (SES) as measured by the proportion of students participating in the …

Modeled And Observed N2 Lyman-Birge-Hopfield Band Emissions Earth's Dayglow: A Comparison, Donald Murray

Electronic Theses and Dissertations

Ultraviolet (UV) spectra obtained from Earth’s dayglow contain important information for understanding the thermosphere, and the N2 Lyman-Birge-Hopfield (LBH) bands are possibly the most useful emission. To be useful, a thorough understanding of how the LBH band emission varies with altitude and latitude is essential to present and future use of this emission by space-based remote sensors. Excited by photoelectron impact on N2 leading to transitions from the a 1Πg state to the ground state, the LBH emissions radiate between 1270 and 2400 Å. In addition to being populated by electron impact excitation, the a 1Πg state is populated by …

High Birefringence Liquid Crystals For Optical Communications, Amanda Jane Parish

Electronic Theses and Dissertations

High birefringence (Δn > 0.4) nematic liquid crystals are particularly attractive for infrared applications because they enable a thinner cell gap to be used for achieving fast response time and improved diffraction efficiency. In this thesis, the mesomorphic and electro‐optic properties of several new fluorinated isothiocyanate (NCS) terphenyl and phenyl tolane single compounds and mixtures are reported. The single compounds demonstrated Δn~0.35‐0.52 in the visible spectral region at room temperature and exhibit relatively low viscosity. It was found that lateral fluorine substitutions and short alkyl chains eliminate smectic phase and lower the melting temperature of the single compounds. However, the consequence …