UNT Theses and Dissertations - 17,929 Matching Results

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First-Time Parenthood: Attachment, Family Variables, Emotional Reactions, and Task Responsibilities as Predictors Of Stress

Description: The purpose of this study was to explore factors which are predictive of parenting stress for first-time parents. Based on attachment theory and empirical research, the factors investigated were the responsibility for child care and housework, the current and retrospective relationship with the family of origin, the change in emotions related to parenthood, the marital relationship, and attachment and individuation.
Date: December 1990
Creator: Abbott, Donna Christine
Partner: UNT Libraries

First-Year Teacher Usage of Manipulatives in Mathematics Instruction: A Case Study

Description: This qualitative case study examined the use of manipulatives in mathematics instruction by six first-year intermediate teachers in a north Texas school district. Their preparation for, access to, and perceptions about manipulatives were examined. Specific content associated with manipulative usage was identified.
Date: December 1989
Creator: Sylvester, Barbara N. (Barbara Nelson)
Partner: UNT Libraries

FISA and warrantless wire-tapping: Does FISA conform to Fourth Amendment standards?

Description: Electronic surveillance for foreign intelligence purposes was largely unregulated prior to 1978. The Foreign Intelligence Surveillance Act of 1978 (hereinafter "FISA") was enacted to implement a judicial authorization process for foreign intelligence electronic surveillance that would effectively balance competing needs for national security and civil liberty under the Fourth Amendment. This study examines the evolution of FISA and its effectiveness under the Fourth Amendment, as assessed by federal reviewing courts and scholars since the statute's enactment. The study concludes that the FISA electronic surveillance authorization process has been effective in providing a constitutional mechanism to obtain foreign intelligence information.
Date: May 2009
Creator: Meyer, Aric
Partner: UNT Libraries

Fitness-Related Alterations in Blood Pressure Control: The Role of the Autonomic Nervous System

Description: Baroreflex function and cardiovascular responses to lower body negative pressure during selective autonomic blockade were evaluated in endurance exercise trained (ET) and untrained (UT) men. Baroreflex function was evaluated using a progressive intravenous infusion of phenylephrine HCL (PE) to a maximum of 0.12 mg/min. Heart rate, arterial blood pressure, cardiac output and forearm blood flow were measured at each infusion rate of PE. The reduction in forearm blood flow and concomitant rise in forearm vascular resistance was the same for each subject group. However, the heart rate decreases per unit increase of systolic or mean blood pressure were significantly (P<.05) less in the ET subjects (0.91 ± 0.30 versus 1.62 ± 0.28 for UT). During progressive lower body negative pressure with no drug intervention, the ET subjects had a significantly (P<.05) greater fall in systolic blood pressure (33.8 ± 4.8 torr versus 16.7 ± 3.9 torr). However, the change in forearm blood flow or resistance was not significantly different between groups. Blockade of parasympathetic receptors with atropine (0.04 mg/kg) eliminated the differences in response to lower body negative pressure. Blockade of cardiac sympathetic receptors with metoprolol (0.02 mg/kg) did not affect the differences observed during the control test. It was concluded that the ET subjects were less effective in regulating blood pressure than the UT subjects, because of 1) an attenuated baroreflex sensitivity, and 2) parasympathetic-mediated depression of cardiac and vasoconstrictive responses to the hypotensive stress.
Date: December 1986
Creator: Smith, Michael Lamar, 1957-
Partner: UNT Libraries

Five Buildings in the Dallas Central Business District by I.M. Pei and Partner Henry N. Cobb: A Stamp on the City's Direction

Description: The purpose of this study is to examine I. M. Pei and his partner Harry Cobb's downtown Dallas architecture within the context of their overall stylistic development. This paper explores the structure of five buildings within the framework of the city, and addresses their possible influence on the city's future architectural direction. The thesis is divided into six chapters. Chapter I introduces and states the problem as it discusses the fabric of Dallas architecture. Chapter II outlines a brief biography of I. M. Pei, looking to those who have influenced him, while discussing the key public buildings of his stylistic development. Chapter III is devoted to Pei's first structure in the city, the Dallas Municipal Administration Center. Chapter IV explores the concepts of his planned Morton H. Meyerson Symphony Center. Chapter V outlines a brief biography and focuses on the work of Harry N. Cobb: One Dallas Centre, ARCO Tower, and the Allied Bank Tower. Chapter VI summarizes the contributions of Pei and Cobb by placing them within the context of twentieth century architecture, and pointing out their specific achievements with their additions to the fabric of Dallas architecture.
Date: December 1986
Creator: Malesky, J. Barney (James Barney)
Partner: UNT Libraries

The Five Dimensions of Professional Learning Communities in Improving Exemplary Texas Elementary Schools: A Descriptive Study

Description: This descriptive study investigated the development of the 5 dimensions of the professional learning community model in 5 economically disadvantaged and diverse Texas elementary schools, which demonstrated improvement in student achievement on the Texas Assessment of Knowledge and Skills (TAKS) over a 5-year period. Each of the schools were given the highest performance rating of Exemplary during the 2008 school year according to criteria developed by the Texas accountability system and had changed from an Acceptable rating in 2004. The purpose of this study was to determine the level of the development of the 5 dimensions of the professional learning community model in improving exemplary Texas elementary schools and to identify and compare the possible commonalities and differences existing between the schools on the 5 dimensions of professional learning communities. The 5 dimensions of the professional learning community model investigated in this study include: 1) shared and supportive leadership, 2) shared values and vision, 3) collective learning and the application of learning, 4) shared personal practice and 5) supportive conditions (collegial relationships and structures). The method used in this study was a mixed method approach that employed a questionnaire, individual principal and teacher interviews and school performance documents to collect data. The questionnaire data was analyzed through descriptive and analytical statistics while the interviews were investigated by identifying and documenting emergent patterns and themes. The findings from this study suggest that sustainable professional learning communities are evident in the high performing schools selected for this study. The study implies the culture of these schools is supported by relationships fostered by trust and mutual respect and their success is attributed to the collaborative, collegial and collective learning of the staff. Staff members from these schools are focused on student learning while campus leadership, grade level and vertical teams provide the structures ...
Date: December 2009
Creator: Blacklock, Phillip Jeffrey
Partner: UNT Libraries

Five Seasons: A composition for flutist and percussionist

Description: Five Seasons is a musical work for flute and percussion. The flutist alternately performs on the C flute with a B foot, alto flute, piccolo, and bass flute in each movement. The percussionist also plays different instruments in each movement: the vibraphone for Mid-Summer; the xylophone for Fall; the woodblock, temple block, and cowbells for Spring; the glockenspiel for Summer; and the marimba for Winter. The five movements of this work - Mid-Summer, Fall, Spring, Summer, and Winter - are based on a combination of Eastern performing practices with Western instruments. The musical characteristics are based on the techniques of fifteenth-century (e.g., isorhythmic technique) and twentieth-century Western music.
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Date: August 2001
Creator: Kim, Chol-Ho
Partner: UNT Libraries

Five soundscapes for acoustic instruments and taped computer music

Description: Inspired by Chinese poems, the overall characteristics of the work reflect the assimilation of several non-Western musical and philosophical influences such as the use of pentatonic scale patterns, the principle of embellishing a single note, and the application of the I-Ching in dealing with active instrumental passages over a long-sustained computer music drone. Traditional Western compositional techniques such as aleatory counterpoint, serialism, and moment form are also employed in the treatment of thematic material, developmental processes and formal design.
Date: August 1998
Creator: Tseng, Yu-Chung
Partner: UNT Libraries

Five Year Band Program for Vanderbilt School

Description: The public school of Vanderbilt, Texas is in the process of building a band. The steady growth of the band will depend upon a long-range planning program. It is the band director's aim to set up such a long-range plan to cover the five years from the 1947 school year and including the 1952 school year. The following chapters will cover most of the phases of the band's work, and that of the director's work, and his relation to the band and the community.
Date: August 1948
Creator: Reves, Wayman Aubrey
Partner: UNT Libraries

The Fixed v. Variable Sampling Interval Shewhart X-Bar Control Chart in the Presence of Positively Autocorrelated Data

Description: This study uses simulation to examine differences between fixed sampling interval (FSI) and variable sampling interval (VSI) Shewhart X-bar control charts for processes that produce positively autocorrelated data. The influence of sample size (1 and 5), autocorrelation parameter, shift in process mean, and length of time between samples is investigated by comparing average time (ATS) and average number of samples (ANSS) to produce an out of control signal for FSI and VSI Shewhart X-bar charts. These comparisons are conducted in two ways: control chart limits pre-set at ±3σ_x / √n and limits computed from the sampling process. Proper interpretation of the Shewhart X-bar chart requires the assumption that observations are statistically independent; however, process data are often autocorrelated over time. Results of this study indicate that increasing the time between samples decreases the effect of positive autocorrelation between samples. Thus, with sufficient time between samples the assumption of independence is essentially not violated. Samples of size 5 produce a faster signal than samples of size 1 with both the FSI and VSI Shewhart X-bar chart when positive autocorrelation is present. However, samples of size 5 require the same time when the data are independent, indicating that this effect is a result of autocorrelation. This research determined that the VSI Shewhart X-bar chart signals increasingly faster than the corresponding FSI chart as the shift in the process mean increases. If the process is likely to exhibit a large shift in the mean, then the VSI technique is recommended. But the faster signaling time of the VSI chart is undesirable when the process is operating on target. However, if the control limits are estimated from process samples, results show that when the process is in control the ARL for the FSI and the ANSS for the VSI are approximately the same, and ...
Date: May 1993
Creator: Harvey, Martha M. (Martha Mattern)
Partner: UNT Libraries

Flexible Digital Authentication Techniques

Description: Abstract This dissertation investigates authentication techniques in some emerging areas. Specifically, authentication schemes have been proposed that are well-suited for embedded systems, and privacy-respecting pay Web sites. With embedded systems, a person could own several devices which are capable of communication and interaction, but these devices use embedded processors whose computational capabilities are limited as compared to desktop computers. Examples of this scenario include entertainment devices or appliances owned by a consumer, multiple control and sensor systems in an automobile or airplane, and environmental controls in a building. An efficient public key cryptosystem has been devised, which provides a complete solution to an embedded system, including protocols for authentication, authenticated key exchange, encryption, and revocation. The new construction is especially suitable for the devices with constrained computing capabilities and resources. Compared with other available authentication schemes, such as X.509, identity-based encryption, etc, the new construction provides unique features such as simplicity, efficiency, forward secrecy, and an efficient re-keying mechanism. In the application scenario for a pay Web site, users may be sensitive about their privacy, and do not wish their behaviors to be tracked by Web sites. Thus, an anonymous authentication scheme is desirable in this case. That is, a user can prove his/her authenticity without revealing his/her identity. On the other hand, the Web site owner would like to prevent a bunch of users from sharing a single subscription while hiding behind user anonymity. The Web site should be able to detect these possible malicious behaviors, and exclude corrupted users from future service. This dissertation extensively discusses anonymous authentication techniques, such as group signature, direct anonymous attestation, and traceable signature. Three anonymous authentication schemes have been proposed, which include a group signature scheme with signature claiming and variable linkability, a scheme for direct anonymous attestation in trusted computing platforms ...
Date: May 2006
Creator: Ge, He
Partner: UNT Libraries

The Flora and Fauna in Eighteenth-Century Colonial Mexican Casta Paintings

Description: The primary objective of this thesis is to identify patterns of appearance among the flora and fauna of selected eighteenth-century New Spanish casta paintings. The objectives of the thesis are to determine what types of flora and fauna are present within selected casta paintings, whether the flora and fauna's provenance is Spanish or Mexican and whether there are any potential associations of particular flora and fauna with the races being depicted in the same composition. I focus my flora and fauna research on three sets of casta paintings produced between 1750 and 1800: Miguel Cabrera's 1763 series, José Joaquín Magón's 1770 casta paintings, and Andrés de Islas' 1774 sequence. Although the paintings fall into the same genre and within a period of a little over a decade, they nevertheless offer different visions of New Spain's natural bounty and include objects designed to satisfy Europe's interest in the exotic.
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Date: May 2006
Creator: Torres, Anita Jacinta
Partner: UNT Libraries

Florence, Biblioteca del Conservatorio di Musica Luigi Cherubini, Manuscript Basevi 2439: Critical Edition and Commentary

Description: The subject of the present study, Florence, Biblioteca del Conservatorio di Musica Luigi Cherubini, MS Basevi 2439, abbreviated Florence 2439,1 contains secular and sacred vocal music of the late fifteenth and early sixteenth centuries, with texts in French, Dutch, Italian, and Latin.
Date: June 1968
Creator: Newton, Paul George, 1930-
Partner: UNT Libraries

Florence, Biblioteca del Conservatorio di musica Luigi Cherubini, manuscript Basevi 2439: critical edition and commentary

Description: The subject of the present study, Florence, Biblioteca del Conservatorio di Musica Luigi Cherubini, MS Basevi 2439, abbreviated Florence 2439,1 contains secular and sacred vocal music of the late fifteenth and early sixteenth centuries, with texts in French, Dutch, Italian, and Latin.
Date: June 1968
Creator: Newton, Paul George
Partner: UNT Libraries

Flow Accelerated Corrosion Experience at Comanche Peak Steam Electric Station

Description: Flow accelerated corrosion (FAC) is a major concern in the power industry as it causes thinning of the pipes by the dissolution of the passive oxide layer formed on the pipe surface. Present research deals with comparing the protection offered by the magnetite (Fe3O4) versus maghemite (γ-Fe2O3) phases thickness loss measurements. Fourier transform infrared spectroscopy (FTIR) is used in distinguishing these two elusive phases of iron oxides. Representative pipes are collected from high pressure steam extraction line of the secondary cycle of unit 2 of Comanche Peak Steam Electric Station (CPSES). Environmental scanning electron microscopy (ESEM) is used for morphological analysis. FTIR and X-ray diffraction (XRD) are used for phase analysis. Morphological analysis showed the presence of porous oxide surfaces with octahedral crystals, scallops and "chimney" like vents. FTIR revealed the predominance of maghemite at the most of the pipe sections. Results of thickness measurements indicate severe thickness loss at the bend areas (extrados) of the pipes.
Date: May 2008
Creator: Nakka, Ravi Kumar
Partner: UNT Libraries

FLP-mediated conditional loss of an essential gene to facilitate complementation assays

Description: Commonly, when it is desirable to replace an essential gene with an allelic series of mutated genes, or genes with altered expression patterns, the complementing constructs are introduced into heterozygous plants, followed by the selection of homozygous null segregants. To overcome this laborious and time-consuming step, the newly developed two-component system utilizes a site-specific recombinase to excise a wild-type copy of the gene of interest from transformed tissues. In the first component (the first vector), a wild-type version of the gene is placed between target sequences recognized by FLP recombinase from the yeast 2 μm plasmid. This construct is transformed into a plant heterozygous for a null mutation at the endogenous locus, and progeny plants carrying the excisable complementing gene and segregating homozygous knockout at the endogenous locus are selected. The second component (the second vector) carries the experimental gene along with the FLP gene. When this construct is introduced, FLP recombinase excises the complementing gene, leaving the experimental gene as the only functional copy. The FLP gene is driven by an egg apparatus specific enhancer (EASE) to ensure excision of the complementing cDNA in the egg cell and zygote following floral-dip transformation. The utility of this system is being tested using various experimental derivatives of the essential sucrose-proton symporter, AtSUC2, which is required for photoassimilate transport.
Date: December 2007
Creator: Ganesan, Savita
Partner: UNT Libraries

Fluency Training as a Pedagogical Tool to Improve Performance of Undergraduate Students Enrolled in the First Financial Accounting Course at a Regional Oklahoma University

Description: This study contributes to the debate on accounting pedagogy in the basic financial accounting course by examining the pedagogical tool of fluency training as a way to improve student performance. Fluency training has been shown to improve performance of students in other academic disciplines.
Date: December 1998
Creator: Huffman, William E. (William Eugene)
Partner: UNT Libraries

Fluorescence labeling and computational analysis of the strut of myosin's 50 kDa cleft.

Description: In order to understand the structural changes in myosin S1, fluorescence polarization and computational dynamics simulations were used. Dynamics simulations on the S1 motor domain indicated that significant flexibility was present throughout the molecular model. The constrained opening versus closing of the 50 kDa cleft appeared to induce opposite directions of movement in the lever arm. A sequence called the "strut" which traverses the 50 kDa cleft and may play an important role in positioning the actomyosin binding interface during actin binding is thought to be intimately linked to distant structural changes in the myosin's nucleotide cleft and neck regions. To study the dynamics of the strut region, a method of fluorescent labeling of the strut was discovered using the dye CY3. CY3 served as a hydrophobic tag for purification by hydrophobic interaction chromatography which enabled the separation of labeled and unlabeled species of S1 including a fraction labeled specifically at the strut sequence. The high specificity of labeling was verified by proteolytic digestions, gel electrophoresis, and mass spectroscopy. Analysis of the labeled S1 by collisional quenching, fluorescence polarization, and actin-activated ATPase activity were consistent with predictions from structural models of the probe's location. Although the fluorescent intensity of the CY3 was insensitive to actin binding, its fluorescence polarization was notably affected. Intriguingly, the mobility of the probe increases upon S1 binding to actin suggesting that the CY3 becomes displaced from interactions with the surface of S1 and is consistent with a structural change in the strut due to cleft motions. Labeling the strut reduced the affinity of S1 for actin but did not prevent actin-activated ATPase activity which makes it a potentially useful probe of the actomyosin interface. The different conformations of myosin S1 indicated that the strut is not as flexible as several other key regions of myosin ...
Date: August 2007
Creator: Gawalapu, Ravi Kumar
Partner: UNT Libraries

Fluoride-Induced Changes in In Vivo Papillary Cyclic AMP

Description: Two separate experiments were designed to measure urinary cyclic AMP and renal papillary cyclic AMP, respectively, Results suggest that urinary cyclic AMP excretion rate is unchanged and cannot be used as an index of tubular sensitivity to either vasopressin or fluoride. However, renal papillary tissue cyclic AMP increased significantly (p<0.05) at plasma fluoride concentrations which result in polyuric renal failure. Further, it appears that fluoride independently stimulates cyclic AMP in the papilla, demonstrated by the additive effect with vasopressin. It was postulated that the defect in water reabsorption induced by fluoride must be at a step subsequent to the generation of cyclic AMP, because one would expect to see an antidiuresis, not a diuresis with increased tissue cyclic AMP.
Date: December 1982
Creator: Maxwell, Jack Allen
Partner: UNT Libraries

Fluorination Effect on the Conformational Properties of Alkanes

Description: A Series of fluorophores of the general formular P(CF2)nP and P(CF2)n-1CF3 has been synthesized. Copper catalyzed coupling of 1-bromopyrene and the corresponding mono and di-iodoperfluoroalkanes were used in most cases. For the n=3 dimer, a novel 1,w-perfluoroalkylation of pyrene via bis-decarboxylation of hexafluorogultaric acid was utilized. These compounds, along with suitable hydrocarbon analogs, are being used to study the flexibility of fluorocarbon chains using emission. We have found that the excimer formation for the fluorinated pyrene monomers is highly dependent on concentration and is less efficient than for pyene. Excimer formation for the fluorinated pyrene dimers is much more efficient than for the fluorocarbon monomers and is only slightly concentraion dependent. Steady-state emission spectra indicate hydrocarbon dimers-models form excimers more efficiently than the fluorinated dimers suggesting the fluorinated chains are stiffer than the hydrocarbons. We conducted the temperature-dependent studies and quantified the conformational difference.
Date: May 2002
Creator: Xu, Wenjian
Partner: UNT Libraries

Fluorine Adsorption and Diffusion in Polycrystalline Silica

Description: The measurement of fluorine penetration into archeological flint artifacts using Nuclear Reaction Analysis (NRA) has been reported to be a potential dating method. However, the mechanism of how fluorine is incorporated into the flint surface, and finally transported into the bulk is not well understood. This research focuses on the study of the fluorine uptake phenomenon of flint mineral in aqueous fluoride solutions. Both theoretical and experimental approaches have been carried out. In a theoretical approach, a pipe-diffusion model was used to simulate the complicated fluorine transportation problem in flint, in which several diffusion mechanisms may be involved.
Date: December 1998
Creator: Jin, Jian-Yue
Partner: UNT Libraries