This study investigated whether a relationship exists between learning style and the self-reported technology-related needs, beliefs, stages of adoption, software expertise, and technology competencies of teachers in a large suburban school district. The Gregorc Style Delineator was used to identify dominant learning style, and the Snapshot Survey was used to measure technology-related needs, beliefs, stages of adoption, and software expertise. Technology competencies were measured using the Technology in Education Competency Survey. Data collected from 499 participants was included in data analysis. The study was conducted at each of the 12 elementary schools of a large suburban district in the Dallas-Fort Worth Metroplex. The findings suggest that there is a significant relationship between learning style and the technology-related needs, stages of adoption, software expertise, and competencies of teachers. The relationship between learning style and technology-related needs was significant at the p < .01 level. The relationships between learning style and technology-related stages of adoption, software expertise, and technology competencies were significant at the p < .05 level. Members of the abstract sequential [AS] learning style group reported having significantly fewer needs and significantly higher stages of adoption, software expertise, and competency than members of one or more of the other learning …

This study seeks to determine the effectiveness of the Challenging Athletes Minds for Personal Success (CHAMPS)/Life Skills program at the University of North Texas, as perceived by the student athletes who participate or participated in this program. The study attempts to measure the extent to which the student athletes feel that the program had value; if they received helpful information to support them through their college career to career transition; if the student athletes felt that the program provided them with skills to encourage better self-esteem; and if they believed that the CHAMPS/Life Skills program provided them with leadership and character education. The study, conducted in the Fall of 2003, had 163 respondents. An instrument was developed to determine student athletes' perceptions of the effectiveness of the CHAMPS/Life Skills program at UNT. The instrument consisted of 30 questions using a Likert-type scale. A Mann-Whitney U, a non-parametric t-Test, was utilized to analyze the data. This type of t-Test was used because it is specifically designed to compare the means of the same variable with two different groups and account for non-homogeneous groups. The lack of homogeneity was very likely influenced by the unequal group sizes. Generally, all aspects of the …

Most colleges and universities invest substantial resources in an effort to strategically plan for a sound financial base. The revenue for the financial base is dependent on student enrollment that must be effectively managed. Increases in the price of tuition and fees can lead to decreased enrollment and negatively impact the revenue of an institution. The increases can also impact the enrollment of certain student populations such as minority students and high school graduates enrolling in college for the first time. Many studies have analyzed the price elasticity and student price response models that have been developed over time by reviewing historical price increases and enrollment across institutions. Few studies have used the models to predict changes in the enrollment of students for one college or university after the increases in the cost of attendance are imposed on students. This study sought to analyze the effectiveness of the most commonly reviewed student price response and price elasticity models in predicting changes in undergraduate enrollment at one metropolitan academic university. The three models introduced by Leslie and Brinkman, St. John and Heller were used to analyze the tuition and fee increases and to identify the likely percentage of increase or decrease …

Individuals diagnosed with schizotypal personality disorder (SPD) exhibit patterns of cognitive deficits in (1) attention (Lees-Roitman, Cornblatt, Bergman, Obuchowski, Mitropoulou, Keefe, Silverman, & Siever, 1997), (2) memory (Bergman, Harvey, Lees-Roitman, Mohs, Margerm, Silverman, & Siever, 1998), (3) executive functioning (Cadenhead, Perry, Shafer, & Braff, 1999), and recently (4) neuromotor functioning (Neumann & Walker, 1999), similar to individuals with a diagnosis of schizophrenia. Furthermore, recent research suggests a link between neuromotor and cognitive functioning in schizophrenia spectrum disorders (SSDs) (Neumann & Walker, 2003). The current study is an extension of research on non-drug-induced neuromotor disturbances in individuals with SPD and examines how such disturbances covary with neurocognitive measures. Approximately thirty-three adults (18-65) were rated for SPD symptoms. Motor assessments included a computerized motor task and finger tapping test. Cognitive assessments included measures of attention, verbal and visual memory, and executive functioning. Consistent with previous research, the SPD group displayed significant right hand (left hemisphere) motor disturbances (i.e., increased force and force variability) compared to healthy controls after excluding all cases reporting a history of head injury. In addition, results indicate significant associations between motor, cognitive, and symptom variables. Consistent with previous research, neuromotor functioning and the relationships between motor and cognitive …

The phenomenon of flavour oscillations of neutrinos created in the atmosphere was first reported by the Super-Kamiokande collaboration in 1998 and since then has been confirmed by Soudan 2 and MACRO. The MINOS Far Detector is the first magnetized neutrino detector able to study atmospheric neutrino oscillations. Although it was designed to detect neutrinos from the NuMI beam, it provides a unique opportunity to measure the oscillation parameters for neutrinos and anti-neutrinos independently. The MINOS Far Detector was completed in August 2003 and since then has collected 2.52 kton-years of atmospheric data. Atmospheric neutrino interactions contained within the volume of the detector are separated from the dominant background from cosmic ray muons. Thirty seven events are selected with an estimated background contamination of less than 10%. Using the detector's magnetic field, 17 neutrino events and 6 anti-neutrino events are identified, 14 events have ambiguous charge. The neutrino oscillation parameters for {nu}{sub {mu}} and {bar {nu}}{sub {mu}} are studied using a maximum likelihood analysis. The measurement does not place constraining limits on the neutrino oscillation parameters due to the limited statistics of the data set analysed. However, this thesis represents the first observation of charge separated atmospheric neutrino interactions. It also …

Thesis written by a student in the UNT Honors College discussing the development of an automatic coupling tester to test for electrode-electrode coupling on an Malt Extract Agar plate.

The b quark fragmentation distribution has been measured, using data registered by the DELPHI experiment at the Z pole, in the years 1994-1995. The measurement made use of 176000 inclusively reconstructed B meson candidates. The errors of this measurement are dominated by systematic effects, the principal ones being related to the energy calibration. The distribution has been established in a nine bin histogram. Its mean value has been found to be &lt;x{sub E}&gt; = 0.704 {+-} 0.001(stat.) {+-} 0.008(syst.). Using this measurement, and other available analyses of the b-quark fragmentation distribution in e{sup +}e{sup -} collisions, the non-perturbative QCD component of the distribution has been extracted independently of any hadronic physics modeling. This distribution depends only on the way the perturbative QCD component has been defined. When the perturbative QCD component is taken from a parton shower Monte-Carlo, the non-perturbative QCD component is rather similar with those obtained from the Lund or Bowler models. When the perturbative QCD component is the result of an analytic NLL computation, the non-perturbative QCD component has to be extended in a non-physical region and thus cannot be described by any hadronic modeling. In the two examples, used to characterize these two situations, which are …

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Utilization of cyanide as the sole nitrogen source by Pseudomonas fluorescens NCIMB 11764 (Pf11764) occurs via oxidative conversion to carbon dioxide and ammonia, the latter satisfying the nitrogen requirement. Substrate attack is initiated oxygenolytically by an enzyme referred to as cyanide oxygenase (CNO), which exhibits properties of a pterin-dependent hydroxylase. The pterin requirement for Pf11764 CNO was satisfied by supplying either the fully (tetrahydro) or partially (dihydro) reduced forms of various pterin compounds at catalytic concentrations (0.5 µM). These compounds included, for example, biopterin, monapterin and neopterin, all of which were also identified in cell extracts. A related CNO-mediated mechanism of cyanide utilization was identified in cyanide-degrading P. putida BCN3. This conclusion was based on (i) the recovery of CO2 and NH3 as enzymatic reaction products, (ii) the dependency of substrate conversion on both O2 and NADH, and (iiii) utilization of cyanide, O2 and NADH in a 1:1:1 reaction stoichiometry. In contrast to findings reported for Pf11764, it was not possible to demonstrate a need for exogenously added pterin as a cofactor for the PpBCN3 enzyme system. However, results which showed that cells of PpBCN3 contained approximately seven times the amount of pterin as Pf11764 (of which a significant portion …

Baeyer-Villiger oxidation of 1,9-dibromopentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione (1,9-dibromo-PCU-8,11-dione) was performed by using an excess amount of m-chloroperbenzoic acid (3 equivalents) and resulted in the formation of the corresponding monolactone. The reaction would not proceed to the dilactone stage. The structure of the reaction product was established unequivocally via single crystal X-ray diffraction. Baeyer-Villiger oxidation of 1,9-dibromo-PCU-8,11-dione using ceric ammonium nitrate (CAN) was also performed and afforded a mixture of lactones. Only one of these lactones, which also contained an alkene functionality, could be isolated and characterized. 1,7-dibromo-PCU-8,11-dione was also reacted with CAN, yielding the mono-lactone, which has also been characterized.

The barrier properties and long term strength retention of polymers are of significant importance in a number of applications. Enhanced lifetime food packaging, substrates for OLED based flexible displays and long duration scientific balloons are among them. Higher material requirements in these applications drive the need for an accurate measurement system. Therefore, a new system was engineered with enhanced sensitivity and accuracy. Permeability of polymers is affected by permeant solubility and diffusion. One effort to decrease diffusion rates is via increasing the transport path length. We explore this through dispersion of layered silicates into polymers. Layered silicates with effective aspect ratio of 1000:1 have shown promise in improving the barrier and mechanical properties of polymers. The surface of these inorganic silicates was modified with surfactants to improve the interaction with organic polymers. The micro and nanoscale dispersion of the layered silicates was probed using optical and transmission microscopy as well as x-ray diffraction. Thermal transitions were analyzed using differential scanning calorimetry. Mechanical and permeability measurements were correlated to the dispersion and increased density. The essential structure-property relationships were established by comparing semicrystalline and amorphous polymers. Semicrystalline polymers selected were nylon-6 and polyethylene terephthalate. The amorphous polymer was polyethylene terphthalate-glycol. Densification …

When I was first introduced to photography, I was mainly drawn to landscape imagery. I enjoyed being a solitary spectator. Over time, inclusions of figurative elements became more and more apparent in my work. I purposefully began to incorporate a figure into my landscapes, ascribing to it a certain nostalgia and a sense of isolation I was experiencing on many levels at that time. Before long, I felt disconnected from these images because of their ambiguity and generalization. I found myself craving more content and personal commitment in my photography. At the end 2003, I started experimenting with a 4" x 5" format camera, which forced me, to some extent, to change my way of photographing and seeing. That is how the beginning of this new body of work was born. I was accustomed to shooting with a 35 mm camera, which allowed me to be spontaneous, quick and immediate. I permanently switched to a large format. I could see myself benefiting from this change. I lost some of the spontaneity that a 35 mm format offers but I gained the beauty of working with larger negatives and the endless possibilities of view camera movements. Thanks to this technical transformation, …

The original HPL algorithm makes the assumption that all data can be fit entirely in the main memory. This assumption will obviously give a good performance due to the absence of disk I/O. However, not all applications can fit their entire data in memory. These applications which require a fair amount of I/O to move data to and from main memory and secondary storage, are more indicative of usage of an Massively Parallel Processor (MPP) System. Given this scenario a well designed I/O architecture will play a significant part in the performance of the MPP System on regular jobs. And, this is not represented in the current Benchmark. The modified HPL algorithm is hoped to be a step in filling this void. The most important factor in the performance of out-of-core algorithms is the actual I/O operations performed and their efficiency in transferring data to/from main memory and disk, Various methods were introduced in the report for performing I/O operations. The I/O method to use depends on the design of the out-of-core algorithm. Conversely, the performance of the out-of-core algorithm is affected by the choice of I/O operations. This implies, good performance is achieved when I/O efficiency is closely tied …

I recently spent a summer as an intern at the Lawrence Livermore National Laboratory. I worked on a project involving the real-time, reagentless, single cell detection of aerosolized pathogens using a novel mass spectrometry approach called Bio-Aerosol Mass Spectrometry (BAMS). Based upon preliminary results showing the differentiation capabilities of BAMS, I would like to explore the development and use of this novel detection system in the context of both environmental and clinical sample pathogen detection. I would also like to explore the broader public health applications that a system such as BAMS might have in terms of infectious disease prevention and control. In order to appreciate the potential of this instrument, I will demonstrate the need for better pathogen detection methods, and outline the instrumentation, data analysis and preliminary results that lead me toward a desire to explore this technology further. I will also discuss potential experiments for the future along with possible problems that may be encountered along the way.

Better devices are needed for the detection of aerosolized biological warfare agents. Advances in the ongoing development of one such device, the BioAerosol Mass Spectrometry (BAMS) system, are described here in detail. The system samples individual, micrometer-sized particles directly from the air and analyzes them in real-time without sample preparation or use of reagents. At the core of the BAMS system is a dual-polarity, single-particle mass spectrometer with a laser based desorption and ionization (DI) system. The mass spectra produced by early proof-of-concept instruments were highly variable and contained limited information to differentiate certain types of similar biological particles. The investigation of this variability and subsequent changes to the DI laser system are described. The modifications have reduced the observed variability and thereby increased the usable information content in the spectra. These improvements would have little value without software to analyze and identify the mass spectra. Important improvements have been made to the algorithms that initially processed and analyzed the data. Single particles can be identified with an impressive level of accuracy, but to obtain significant reductions in the overall false alarm rate of the BAMS instrument, alarm decisions must be made dynamically on the basis of multiple analyzed particles. …

TNT (2,4,6-trinitrotoluene) is a persistent contaminant at many military installations and poses a threat to aquatic ecosystems. Data from environmental fate and toxicity studies with TNT revealed that sediment toxicity test procedures required modification to accurately assess sediment TNT toxicity. Key modifications included aging TNT-spiked sediments 8-14 d, basing lethal dose on measured sediment concentrations of the molar sum of TNT and its main nitroaromatic (NA) transformation products (SNA), basing sublethal dose on average sediment SNA concentrations obtained from integration of sediment SNA transformation models, avoiding overlying water exchanges, and minimizing toxicity test durations. Solid phase microextraction fibers (SPMEs) were investigated as a biomimetic chemical measure of toxicity and bioavailability. Both organism and SPME concentrations provided measures of lethal dose independent of exposure scenario (TNT-spiked sediment or TNT-spiked water) for Tubifex tubifex. Among all benthic organisms tested (Chironomus tentans, Ceriodaphnia dubia, T. tubifex) and matrixes, median lethal dose (LC50) estimates based on SPME and organism concentrations ranged from 12.6 to 55.3 mmol SNA/ml polyacrylate and 83.4 to 172.3 nmol SNA/g tissue, ww, respectively. For Tubifex, LC50s (95% CI) based on SNA concentrations in sediment and SPMEs were 223 (209-238) nmol SNA/g, dw and 27.8 (26.0-29.8) mmol SNA/ml, respectively. Reproductive effects …

This study identifies the biogeographic factors that structure small mammal communities on mountains of the Colorado Plateau and adjacent regions. Forty six isolated ranges were characterized across a 5-state study area encompassing the Colorado Plateau, including the central high plateaus of Utah and the Basin and Range Province (i.e. the Great Basin and mountains of Arizona and New Mexico). Presence/absence data of 25 montane mammal species were used to explore the interactions between historical and ecological processes affecting local and regional diversity patterns. Multivariate analyses, such as non-metric dimensional scaling, were used to explore factors which influence community composition. Results of these analyses revealed the Colorado River as a significant biogeographic barrier that affects montane mammal community structure. MtDNA cytochrome b sequence variation was analyzed among populations of the long-tailed vole, Microtus longicaudus, sampled from five interior ranges of the Colorado Plateau- Abajo, LaSal, Henry, and Chuska Mts., and Boulder Mountain of the Aquarius Plateau-and analyzed using traditional phylogenetic approaches (parsimony and likelihood) as well as nested clade analysis. Results support previous documentation of a major east-west phylogeographic break occurring between populations southeast of the Colorado River (eastern Arizona, Colorado, Wyoming and New Mexico) and all other western populations, which …

This problem in lieu of thesis is a discussion of two topics: Brownian movement and quantum computers. Brownian movement is a physical phenomenon in which the particle velocity is constantly undergoing random fluctuations. Chapters 2, 3 and 4, describe Brownian motion from three different perspectives. The next four chapters are devoted to the subject of quantum computers, which are the signal of a new era of technology and science combined together. In the first chapter I present to a reader the two topics of my problem in lieu of thesis. In the second chapter I explain the idea of Brownian motion, its interpretation as a stochastic process and I find its distribution function. The next chapter illustrates the probabilistic picture of Brownian motion, where the statistical averages over trajectories are related to the probability distribution function. Chapter 4 shows how to derive the Langevin equation, introduced in chapter 1, using a Hamiltonian picture of a bath with infinite number of harmonic oscillators. The chapter 5 explains how the idea of quantum computers was developed and how step-by-step all the puzzles for the field of quantum computers were created. The next chapter, chapter 6, discus the basic quantum unit of information …

Cowpea, Vigna unguiculata (L.) Walp is an excellent source of protein, vitamins and minerals and a major food crop many parts of Africa. Optimal production levels are hampered by insect pests and diseases. Biotechnological techniques such as tissue culture and genetic engineering can aid in the development of varieties with resistance to insect pests and diseases. The objective of this study was to investigate conditions necessary for the development of a reproducible tissue culture system that can be applied to regenerate transformed cells from culture. The in vitro manipulation of cowpea using Murashige and Skoog (MS) medium, auxins and cytokinins resulted in the formation of callus and rhizogenesis. Calli that were formed were separated into six classes based on color and texture. Yellowish friable callus, yellowish compact, soft yellowish callus and green and white were composed of largely vacuolated cells and were non-regenerative. Friable green callus was the most prevalent callus type and could form of roots in some hormone combinations. Green spots were formed on hard compact green callus. The green spots became nodular, forming root primordia and ultimately giving rise to roots. None of the six calli types gave rise to the formation of shoots. Embryogenic callus was …

The majority of books about Saint-Säens cover his life, compositions, contemporaries, and French music in general. Although his life is well documented, most sources present only brief analyses of his works; there is not one single comprehensive and exhaustive study of the Piano Concerto in F Major, Opus 103, available in the current literature. This study aims at filling the gap by providing other musicians interested in performing this piece with an initial study-guide. The research for this study focuses on several aspects of Saint-Säens' music. The currently available literature and past research is thoroughly examined, appraised, and quoted when relevant to the discussion. The original score of the concerto is analyzed regarding its form, compositional style, and performance indications. Diagrams, charts, and musical examples are presented to illustrate and substantiate the researcher's conclusions. Chapter I presents the topic and purpose of this study, a brief biography of Saint-Säens, a chronological overview of his five piano concertos, and the historical background of the Piano Concerto No. 5 in F Major, Opus 103. Chapter II presents a formal analysis and a compositional analysis of Opus 103. Chapter III presents a perspective of Saint-Säens playing style and performance recommendations by the author. …

One of the leading problems that will be carried into the 21st century is that of alternative fuels to get our planet away from the consumption of fossil fuels. There has been a growing interest in the use of nanotechnology to somehow aid in this progression. There are several unanswered questions in how to do this. It is known that carbon nanotubes will store hydrogen but it is unclear how to increase that storage capacity and how to remove this hydrogen fuel once stored. This document offers some answers to these questions. It is possible to implant more hydrogen in a nanotube sample using a technique of ion implantation at energy levels ~50keV and below. This, accompanied with the rapid removal of that stored hydrogen through the application of a microwave field, proves to be one promising avenue to solve these two unanswered questions.

High-pressure catalytic reactions and associated processes, such as adsorption have been studied on a molecular level on single crystal surfaces. Sum Frequency Generation (SFG) vibrational spectroscopy together with Auger Electron Spectroscopy (AES), Temperature Programmed Desorption (TPD) and Gas Chromatography (GC) were used to investigate the nature of species on catalytic surfaces and to measure the catalytic reaction rates. Special attention has been directed at studying high-pressure reactions and in particular, ammonia synthesis in order to identify reaction intermediates and the influence of adsorbates on the surface during reaction conditions. The adsorption of gases N{sub 2}, H{sub 2}, O{sub 2} and NH{sub 3} that play a role in ammonia synthesis have been studied on the Fe(111) crystal surface by sum frequency generation vibrational spectroscopy using an integrated Ultra-High Vacuum (UHV)/high-pressure system. SFG spectra are presented for the dissociation intermediates, NH{sub 2} ({approx}3325 cm{sup -1}) and NH ({approx}3235 cm{sup -1}) under high pressure of ammonia (200 Torr) on the clean Fe(111) surface. Addition of 0.5 Torr of oxygen to 200 Torr of ammonia does not significantly change the bonding of dissociation intermediates to the surface. However, it leads to a phase change of nearly 180{sup o} between the resonant and non-resonant second …

Quantitative knowledge of the fundamental structure and substrate binding, as well as the direct measurement of conformational changes, are essential to the development of self-assembled monolayers (SAMs) and surface-attached interlocking molecules, catenanes and rotaxanes. These monolayers are vital to development of nano-mechanical, molecular electronic, and biological/chemical sensor applications. This dissertation investigates properties of functionalized SAMs in sulfur-gold based adsorbed molecular monolayers using quantitative spectroscopic techniques including near-edge x-ray absorption fine structure spectroscopy (NEXAFS) and x-ray photoelectron spectroscopy (XPS). The stability of the gold-thiolate interface is addressed. A simple model SAM consisting of dodecanethiol adsorbed on Au(111) degrades significantly in less than 24 hours under ambient laboratory air. S 2p and O 1s XPS show the gold-bound thiolates oxidize to sulfinates and sulfonates. A reduction of organic material on the surface and a decrease in order are observed as the layer degrades. The effect of the carboxyl vs. carboxylate functionalization on SAM structure is investigated. Carboxyl-terminated layers consisting of long alkyl-chain thiols vs. thioctic acid with short, sterically separated, alkyl groups are compared and contrasted. NEXAFS shows a conformational change, or chemical switchability, with carboxyl groups tilted over and carboxylate endgroups more upright. Surface-attached loops and simple surface-attached rotaxanes are quantitatively …

Sum frequency generation (SFG) vibrational spectroscopy, atomic force microscopy (AFM), and other complementary surface-sensitive techniques have been used to study the surface molecular structure and surface mechanical behavior of biologically-relevant polymer systems. SFG and AFM have emerged as powerful analytical tools to deduce structure/property relationships, in situ, for polymers at air, liquid and solid interfaces. The experiments described in this dissertation have been performed to understand how polymer surface properties are linked to polymer bulk composition, substrate hydrophobicity, changes in the ambient environment (e.g., humidity and temperature), or the adsorption of macromolecules. The correlation of spectroscopic and mechanical data by SFG and AFM can become a powerful methodology to study and engineer materials with tailored surface properties. The overarching theme of this research is the interrogation of systems of increasing structural complexity, which allows us to extend conclusions made on simpler model systems. We begin by systematically describing the surface molecular composition and mechanical properties of polymers, copolymers, and blends having simple linear architectures. Subsequent chapters focus on networked hydrogel materials used as soft contact lenses and the adsorption of protein and surfactant at the polymer/liquid interface. The power of SFG is immediately demonstrated in experiments which identify the chemical …