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A Case Study of 1:1 Technology Policies in Four Texas High Schools and Their Relationship to Practice

Description: With increasing emphasis on technology in schools, the importance of technology policies is great. This study investigated policies for four 1:1 secondary schools in Texas (schools with a ratio of one computing device per student), particularly with respect to the relationship of those policies to practice. The purpose of the study was to determine the current status of the National Education Technology Standards (NETS) essential conditions as reflected in policy and the relationship of those conditions to practice as measured through levels of technology usage and teaching innovation. Schools were selected through purposive, criterion sampling. Open-ended interviews were conducted with twelve participants (principals, technology directors, and superintendents). Policies were rated by campus principals and the researcher using a rubric based on the NETS essential conditions. Finally, surveys of proficiency and readiness measures were collected from 156 teachers using the School Technology and Readiness (STaR) instrument and the Levels of Teaching Innovation (LoTI) instrument. Interviews were transcribed and coded using structural and frequency coding. Policies were analyzed using magnitude coding and policy ratings. A qualitative analysis determined patterns between policy and practice. Quantitative data collected from surveys were measured against policy ratings and magnitude coding using bivariate correlation methods in SPSS. Quantitative analysis revealed two statistically significant relationships between policy and reported levels of practice in the classroom. Qualitative elements of the study from interviews and policy ratings revealed six findings that may explain a lack of correlation between policy and practice: a lack of ability for leadership to identify 1:1 program policy; lack among school leaders of perceived relationship between policy and practice; a belief among leaders that they are communicating policy to stakeholders even though they demonstrated difficulty in articulating policy; an inability to identify specific research-based theoretical foundations in policy; a lack of meaningful measurement of practices; and ...
Date: December 2013
Creator: Bauter, Cynthia
Partner: UNT Libraries

Homologs of Mammalian Lysosomal Lipase in Arabidopsis and Their Roles in Lipid Droplet Dynamics

Description: Lipid droplets (LDs) are organelles with many functions in cells and numerous protein interactors facilitate their biogenesis, maintenance, and turnover. The mammalian lipase responsible for LD turnover during lipophagy, LipA, has two candidate homologs in Arabidopsis: MPL1 and LIP1. One or both of these plant homologs may function in a similar manner to mammalian LipA, providing an LD breakdown pathway. To test this hypothesis, wild type (WT) Arabidopsis plants, MPL1 over-expressing (OE) mutants, and T-DNA insertion mutants of MPL1 (mpl1) and LIP1 (lip1) were examined for LD phenotypes in normal conditions and in environments where LD numbers are known to fluctuate. Plants to be imaged by confocal microscopy were exposed to heat stress and wounding to increase LD accumulation, senescence was induced in leaves to deplete lipids, and LDs were imaged throughout the day/night period to observe their diurnal regulation. The mutation of both MPL1 and LIP1 lead to an increase in LDs within the leaf mesophyll cells, although the spatial distribution of the LDs differed between the two mutants. mpl1 mutants had disrupted diurnal regulation of their LDs, but lip1 mutants did not. Alternately, lip1 mutants retained LDs during dark-induced senescence, and mpl1 mutants did not. Together these results suggest that MPL1 and LIP1 are likely both important for LD dynamics; however they appear have roles in different aspects of LD accumulation and turnover.
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Date: December 2017
Creator: McClinchie, Elizabeth A
Partner: UNT Libraries

Some Amine Derivatives of 1,4-naphthoquinone

Description: It was the aim of this investigation to prepare derivatives of 1,4-naphthoquinone substituted at the 2- and 3- positions with various amino groups. 2,3-Dichloro-1,4-naphthoquinone was selected as the starting material because of the possibility of replacing the chloro groups in direct substitution reactions with amines.
Date: August 1959
Creator: Cunningham, Robert Gipson
Partner: UNT Libraries

Baseband Noise Suppression in Ofdm Using Kalman Filter

Description: As the technology is advances the reduced size of hardware gives rise to an additive 1/f baseband noise. This additive 1/f noise is a system noise generated due to miniaturization of hardware and affects the lower frequencies. Though 1/f noise does not show much effect in wide band channels because of its nature to affect only certain frequencies, 1/f noise becomes a prominent in OFDM communication systems where narrow band channels are used. in this thesis, I study the effects of 1/f noise on the OFDM systems and implement algorithms for estimation and suppression of the noise using Kalman filter. Suppression of the noise is achieved by subtracting the estimated noise from the received noise. I show that the performance of the system is considerably improved by applying the 1/f noise suppression.
Date: May 2012
Creator: Rodda, Lasya
Partner: UNT Libraries

Phenotypic Analysis of Medicago truncatula NPF1.7 Over-Expressing Plants Grown under Different Nitrate Conditions

Description: Plants have many nitrate transporters; in the model legume Medicago truncatula, MtNPF1.7 is among them. MtNPF1.7 is important for M. truncatula growth and it has been established that MtNPF1.7 is a high affinity nitrate transporter. M. truncatula plants with mutations in MtNPF1.7 gene show defects during plants growth, with striking abnormalities in nodule development and root architecture. Nitrogen fixation is an energy expensive process; when legumes have sufficient bioavailable nitrogen like nitrate available, it suppresses nodulation and nitrogen fixation. Previous preliminary results in our lab showed that plants constitutively expressing MtNPF1.7 have a growth phenotype in the absence of nitrate, but no data was available on how M. truncatula plants constitutively expressing MtNPF1.7 are affected by the presence of nitrate. For my research, I confirmed the preliminary results on the growth of M. truncatula plants overexpressing NPF1.7 and examined these plants' phenotypes when nitrate was not provided in the growth media and when it was provided at two different concentrations. Compared with wild type A17, plants constitutively expressing MtNPF1.7 gene grow larger, have more lateral roots and more nodules when grown in the absence of nitrate and when 0.2 mM KNO3 was provided. At 1 mM KNO3, there are fewer differences between wild type A17 and plants constitutively expressing the MtNPF1.7 gene. Compared with wild type A17, plants constitutively expressing the MtNPF1.7 gene flower earlier, which indicates MtNPF1.7 gene may have a function in plant flowering.
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Date: December 2017
Creator: Cai, Jingya
Partner: UNT Libraries

The Impact of Causative Genes on Neuropsychological Functioning in Familial Early-Onset Alzheimer's Disease: A Meta-Analysis

Description: Mutations of three genes encoding amyloid precursor protein (APP), presenilin-1 (PSEN1), and presenilin-2 (PSEN2) have been shown to reliably result in familial early-onset Alzheimer's disease (FAD); a rare, but catastrophic, subtype of Alzheimer's disease (AD) marked by symptom emergence before age 65 as well as accelerated cognitive deterioration. The current study represents the first known meta-analysis on the association of APP, PSEN1 or PSEN2 on neurocognitive variables. A total of 278 FAD mutation-carriers (FAD-MC) and 284 cognitively healthy non-mutation-carriers (NC) across 10 independent investigations meeting inclusion criteria were chosen for the current meta-analysis (random effects design). Findings revealed an overarching trend of poorer performance by FAD-MC individuals compared to NC individuals across the majority of cognitive domains identified. Significant differences in effect sizes suggested FAD-MC individuals exhibited worse performance on measures of attention, explicit memory, fluency, primary memory, verbal, and visuospatial functioning. Findings indicative of differential sensitivity to cognitive domain impairments across FAD-MC and NC groups inform neuropsychological descriptions of individuals in preclinical phases of FAD.
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Date: May 2017
Creator: Smotherman, Jesse M
Partner: UNT Libraries

Derivatives of 1,4-Naphthoquinone and 1,4-Anthraquinone

Description: The purpose of this investigation was the synthesis of some 1,4-naphthoquinones and 1,4-anthraquinones. It will be shown that some of these substituted quinones exhibit physiological properties.
Date: August 1959
Creator: Aboytes, Peter
Partner: UNT Libraries

The Stereochemistry of 1,4-Di-Tert-Butyl-1,4-Dihydronaphthalene

Description: A new approach was taken in the elucidation of the stereochemistry of the symmetrically 1,4-disubstituted 1,4-dihydronaphthalene systems which show deceptively simple NMR spectra. Thus, the stereochemistry of 1,4-di-tert-butyl-1,4-dihydronaphthalene was established unequivocally. The epoxide derivative, the subject compound, 1,4-di-tertbutyl-2, 3-epoxy-1, 4-dihydronaphthalene, was formed and its trans stereochemistry was established by ¹H NMR and ¹³C NMR. A lanthanide shift study was also conducted on the epoxide derivative, further proving the trans stereochemistry. One of the lanthanide shifted spectra was analyzed using the LAACOON III computer program and the true coupling constants obtained this way were in excellent agreement with the experimental spectrum. Establishing the trans stereochemistry of the epoxide derivative proved the trans stereochemistry of 1,4-di-tert-butyl-1,4-dihydronaphthalene.
Date: December 1980
Creator: McDaniel, Oya A.
Partner: UNT Libraries

Structural Octatonicism in Cindy McTee's Symphony No.1: Ballet for Orchestra

Description: Cindy McTee's Symphony No. 1: Ballet for Orchestra is composed primarily of pitch materials from the octatonic collections that contain both diatonic and non-diatonic relationships in the themes, harmonic content, and larger structure of the symphony. Because the octatonic collections contain the potential for both diatonic and non-diatonic relationships, the piece is argued to have octatonic structure, as the octatonic collection is capable of producing both relationships. The second chapter contains a review of the literature, focusing particularly on the work of Arthur Berger, Pieter C. van den Toorn, Richard Taruskin, and Allen Forte. Next, the octatonic structure of the symphony is shown in the thematic material. Finally, the harmonic support and large-scale structure of the piece are shown to contain octatonic relationships as well.
Date: August 2007
Creator: Weaver, Jennifer L.
Partner: UNT Libraries

Expansion of Musical Styles, Function of Texture, and Performing Techniques in Brian Lock's Sonic Archaeologies No. 1

Description: British composer Brian Lock merges the composition styles of Alexander Goehr, Henryk Górecki and Witold Lutoslawski in his innovative works for instrumental sounds and electronics. His most recent work for flute, Sonic Archaeologies No.1, was premiered at the University of North Texas by Mary Karen Clardy, flute; Brian Lock, piano/electric keyboard; and Daniel Pardo, laptop/live mixing. The purpose of this dissertation is to provide flutists with artistic and technical guidance in preparing this work for flute, prerecorded orchestra, interactive electronics and improvisatory accompaniment. Sonic Archaeologies No. 1, a piece in five movements (Black Rain, Psychomania, Kodo, Susperia, and Deep in the Machine), incorporates contemporary techniques to create sounds other than the Western concert flute, with the use of live reinforcement devices such as microphones and time-based audio effects within a D.A.W. (Digital Audio Workstation.) Reggae, Hip-Hop and cinematic styles are juxtaposed within the work, fusing current genres with traditional rhythmic forms like the ones found in a bourrée. As the solo instrument, flute provides more textural than melodic elements, and the performer is required to interact with an unpredictable sonic soundscape as a result of the improvisatory element of the keyboards and computer. The notation of Sonic Archaeologies No.1 invites interpretation blending and altering traditional sounds through microphones and a processed signal flow. The performance guide will address acoustical considerations when the flute sound is being manipulated by dynamic and time-based processors in live performance; the interaction between the flute, electronics and acoustic spaces; the elements of sound production that provide interpretation of contemporary popular styles; and the opportunities for the performer to find, explore and develop artistry beyond the limitations of music notation.
Date: May 2016
Creator: Pardo, Daniel A
Partner: UNT Libraries

Scattering Cross-sections of 4/1 Prolate Spheroids

Description: This is a report of the second in a projected series of experiments at North Texas State College designed for obtaining information about the microwave scattering properties of various shaped objects.
Date: 1956
Creator: Tompkins, Keith W.
Partner: UNT Libraries

Barbituric Acids. VIII. 5-substituted-5-(1-pyrrolidyl)barbituric Acids

Description: The purpose of this investigation then was the preparation of a series of 5-substituted-5-(1-pyrrolidyl)barbituric acids in which R would consist of alkyl groups ranging in size from methyl to amyl, and other groups such as phenyl and benzyl. These compounds are to be tested elsewhere for hypnotic and anticonvulsant activity.
Date: 1957
Creator: Compton, Ross Davis
Partner: UNT Libraries

Lind, James Meyer the Trumpet Concertos of Anthony Plog: a Performer’s Guide

Description: Anthony Plog (b. 1947) has contributed several notable works for brass instruments. He is known for writing extremely technically challenging works that contain angular melodies, fast rhythms and a large degree of chromaticism. Though his music is difficult, it also conveys intense emotions. His music for trumpet, specifically Concerto no. 1 for Trumpet, Brass Ensemble and Percussion and Concerto no. 2 for Trumpet and Orchestra, represents a zenith in his compositional development. This dissertation examines Concerto no. 1 and Concerto no. 2 from a performer’s perspective to better understand the stylistic characteristics and challenges encountered in his music. Each concerto is examined in terms of rhythmic structure, intervallic structure, thematic material, motivic material and form.
Date: August 2012
Creator: Lind, James Meyer
Partner: UNT Libraries

L-asparaginase II Production by Escherichia coli

Description: Growth of Escherichia coli A-l under aerobic conditions in an enriched medium with a total amount of 0.2 per cent glucose was biphasic and asparaginase II activity was detected after depletion of ammonia from the growth medium in the second phase of growth. Glucose was exhausted two hours before ammonia and three hours before asparaginase II activity was detected. The concentration of 3',5'-cyclic adenosine monophosphate was found to fluctuate when the dissolved oxygen in the medium reached a low level, when glucose and ammonia were exhausted, and when the cells entered the second stationary phase of growth. Culture tube studies of the growth of E_j_ coli A-l in three per cent nutrient broth with varied concentrations of ammonium chloride and potassium nitrate gave lower specific activity of asparaginase II when this was compared to that seen in three per cent nutrient broth alone. The addition of glucose to the same medium before asparaginase II activity was detected resulted in the production of acid by E. coli A-l with cessation of growth; however, addition after L-asparaginase synthesis had started did not affect the specific activity of the enzyme. The addition of ammonium chloride suppressed L-asparaginase synthesis, but addition after enzyme synthesis started had no affect. These findings suggest that asparaginase II is produced by E. coli A-l in response to low concentrations of ammonia and that exogenously supplied nitrogen compounds may play a major role in the regulation of this enzyme. It is suggested that E. coli A-l produced L-asparaginase in order to obtain ammonia for the synthesis of glutamine from glutamate. The synthesis of glutamine from glutamate is the first step of a highly branched pathway which ultimately leads to the synthesis of many of the important macromolecules of the cell.
Date: May 1985
Creator: Johnson, Terrance L. (Terrance Lewyne), 1950-
Partner: UNT Libraries

Effect of Amino Acids on Growth and Cartenogenesis in Corynebacterium Species Strain 7E1C

Description: Studies were evaluated on the effects of known growth factors on the growth and carotenogenesis of Corynebacterium species strain 7ElC. The complex medium, Tryptic Soy Broth,was found to stimulate growth and production of more pigment in the light and in the dark than did a mineral salts-glucose medium. A complete amino acid mixture added to LSG enhanced carotenogenesis in the dark in Corynebacterium 7ElC, while B-vitamins retarded carotenogenesis. No absolute requirement for one or more amino acids was found,indicating a multiple amino acid requirement. The fewest amino acids found to stimulate carotenogenesis in the dark were a combination of those in the Serine and Histidine families which include serine, glycine, cysteine, and histidine.
Date: May 1977
Creator: Coughran, Carolyn S.
Partner: UNT Libraries

The Unpublished Works for Clarinet by Alexander Grechaninov: Preparing a Performance Edition of the Sonata No. 1 for Clarinet and Piano, Op. 161

Description: Alexander Grechaninov was one of the most important composers of the late Russian Romantic School. By the second half of the twentieth century he remained one of the few living composers who continued the traditions of the great Russian Romantic masters, such as Tchaikovsky and Rimsky-Korsakov. He is primarily known for his liturgical works, which are truly masterpieces of this genre. Because many of his instrumental works remain unpublished, particularly the chamber works, they continue to be undeservedly ignored in the concert hall. Grechaninov's unpublished works for clarinet include Septet for Clarinet, Bassoon and String Quintet, Op. 172a, Serenade for Clarinet and String Orchestra (without opus number), and Sonata No. 1 for Clarinet and Piano, Op. 161. This project not only brings to light Grechaninov's unpublished clarinet works, but also emphasizes the importance of his published clarinet pieces which have to date been forgotten, especially in the United States. The writer prepares a performance edition of the Sonata No. 1, Op.161 from Grechaninov's original autograph manuscript which is held in the New York Public Library's Toscanini Archives. After a brief introduction, the document describes Grechaninov's biography, including his historical and societal background, compositional growth throughout his career, and outside influences to which he would have been exposed (Chapter 2). Chapter 3 discusses in details Grechaninov's compositional output and distinct features of his style. Chapters 4 and 5 discuss the published and unpublished works for clarinet by Grechaninov. Chapter 6 provides a detailed structural and tonal analysis of the Sonata No. 1, Op. 161 and discusses the process of editing. Included in the appendices are: performance edition of the Sonata No. 1 for Clarinet and Piano, Op. 161 (score and clarinet part); photocopy of the original autograph manuscript of the Sonata No. 1 for Clarinet and Piano, Op. 161 (score and ...
Date: August 2008
Creator: Perevertailenko, Dmytro Olexandrovich
Partner: UNT Libraries

A Performance Guide to Luigi Nono's Post-Prae-Ludium No. 1 "Per Donau"

Description: Luigi Nono's work Post-Prae-Ludium No.1 "per Donau" represents a model for the emerging genre of electroacoustic tuba music. It is important to preserve this electroacoustic work because of its value to the tuba literature. Not only is it one of the first electroacoustic works for the tuba, but it also was composed by a man who is highly regarded in the field of music composition. Its preservation will be difficult because of the rapid advancement in technology. Within the last three decades of existence, the technology has evolved three times. An examination of the performance practice in Post-Prae-Ludium was undertaken to understand the demand on the performer required to play this work. This study will look at both non-traditional performance practices, as well as an inherent problem of how the advancement of technology can actually threaten the survival of a work dependent upon a specific version of electronic technology. Nono worked in collaboration with Giancarlo Schiaffini to compose a work for tuba and live electronics. Correspondence with Schiaffini has provided his thoughts on the collaboration of Post-Prae-Ludium with Nono and given a better understanding of how to perform the work. Technology will change, and these current adaptations of Post-Prae-Ludium may not be valid in one or two decades. However, with the description and instruction given by Nono and Schiaffini, in addition to recordings made of Post-Prae-Ludium, there is a record from which to reproduce this work. This study provides a source allowing performers to reproduce this work, thereby preserving it for future performers.
Date: August 2009
Creator: Tignor, Scott Edward
Partner: UNT Libraries