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The Information Environment of Academic Library Directors: Use of Information Resources and Communication Technologies

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This study focuses on the use of information resources and communication technologies, both traditional and electronic, by academic library directors. The purpose is to improve understanding of managerial behavior when using information resources and communication technologies within a shared information environment. Taylor's concept of an information use environment is used to capture the elements associated with information use and communication within the context of decision-making styles, managerial roles, organizational environments, and professional communities. This qualitative study uses interviews, observations, questionnaires, and documents. Library directors participating in the study are from doctoral-degree granting universities in the southwestern United States. Data collection involved on-site observations with a PDA (personal digital assistant), structured interviews with library directors and their administrative assistants, the Decision Style Inventory, and a questionnaire based on Mintzberg's managerial roles. Findings show the existence of a continuum in managerial activities between an Administrator and an Administrator/Academic as critical to understanding information use and communication patterns among library directors. There is a gap between self-perception of managerial activities and actual performance, a finding that would not have surfaced without the use of multiple methods. Other findings include the need for a technical ombudsman, a managerial-level position reporting to the library director; …
Date: May 2002
Creator: Koelker, Karen June
System: The UNT Digital Library

A Study of Perceptually Tuned, Wavelet Based, Rate Scalable, Image and Video Compression

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In this dissertation, first, we have proposed and implemented a new perceptually tuned wavelet based, rate scalable, and color image encoding/decoding system based on the human perceptual model. It is based on state-of-the-art research on embedded wavelet image compression technique, Contrast Sensitivity Function (CSF) for Human Visual System (HVS) and extends this scheme to handle optimal bit allocation among multiple bands, such as Y, Cb, and Cr. Our experimental image codec shows very exciting results in compression performance and visual quality comparing to the new wavelet based international still image compression standard - JPEG 2000. On the other hand, our codec also shows significant better speed performance and comparable visual quality in comparison to the best codec available in rate scalable color image compression - CSPIHT that is based on Set Partition In Hierarchical Tree (SPIHT) and Karhunen-Loeve Transform (KLT). Secondly, a novel wavelet based interframe compression scheme has been developed and put into practice. It is based on the Flexible Block Wavelet Transform (FBWT) that we have developed. FBWT based interframe compression is very efficient in both compression and speed performance. The compression performance of our video codec is compared with H263+. At the same bit rate, our encoder, …
Date: May 2002
Creator: Wei, Ming
System: The UNT Digital Library

Characterization of cDNA and Genomic Clones for a Palmitoyl-acyl Carrier Protein Thioesterase and an Osmotin-Like PR5 Protein in Gossypium Hirsutum.

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Putative cotton cDNA clones and cognate genomic clones for a palmitoyl-acyl carrier protein (ACP) thioesterase (PATE) and an osmotin-like pathogenesis-related 5 (PR5) protein have been isolated and characterized. PATE is a class B fatty acid thioesterase with specificity for saturated long-chain fatty acids such as palmitate, and is implicated as a key enzyme to be targeted for regulation of fatty acid synthesis in order to alter cotton seed oil profiles. A nearly full-length 1.7-kb cDNA clone was isolated using a hybridization probe derived from an Arabidopsis PATE cDNA clone designated TE 3-2. A 17-kb genomic segment encompassing the PATE gene was also isolated, which has six exons and five introns with high sequence identity with other FatB cDNA/gene sequences. The deduced PATE preprotein amino acid sequence of 413 residues has putative signal sequences for targeting to the chloroplast stroma. PR5 proteins called osmotins are made in response to fungal pathogen stress or osmotic stress (water deprivation or salt exposure). Osmotins may actually form pores in fungal membranes, leading to osmotic rupture and destruction of the fungal cells. A cotton osmotin-like PR5 cDNA insert of 1,052 base-pairs was isolated and shown to encode a preprotein of 242 amino acids and is …
Date: May 2002
Creator: Yoder, David W.
System: The UNT Digital Library
Music for Solo Bassoon and Bassoon Quartet by Pulitzer Prize Winners: A Guide to Performance (open access)

Music for Solo Bassoon and Bassoon Quartet by Pulitzer Prize Winners: A Guide to Performance

The Pulitzer Prize in Music has been associated with excellence in American composition since 1943, when it first honored William Schuman for his Secular Cantata No. 2: A Free Song. In the years that followed, this award has recognized America's most eminent composers, placing many of their works in the standard orchestral, chamber and solo repertoire. Aaron Copland, Samuel Barber, Walter Piston and Elliott Carter are but a few of the composers who have been honored by this most prestigious award. Several of these Pulitzer Prize-winning composers have made significant contributions to the solo and chamber music repertories of the bassoon, an instrument that had a limited repertoire until the beginning of the twentieth century. The purpose of this project is to draw attention to the fact that America's most honored composers have enlarged and enriched the repertoire of the solo bassoon and bassoon quartet. The works that will be discussed in this document include: Quartettino for Four Bassoons (1939) - William Schuman, Three Inventions for Solo Bassoon (1962) - George Perle, Canzonetta (1962) - John Harbison, Metamorphoses for Bassoon Solo (1991) - Leslie Bassett and “How like pellucid statues, Daddy. Or like a . . . an engine” (1994) …
Date: May 2002
Creator: Worzbyt, Jason Walter
System: The UNT Digital Library
Ecology of Chironomids Associated with Myriophyllum Spicatum L. and Heteranthera Dubia Macm (open access)

Ecology of Chironomids Associated with Myriophyllum Spicatum L. and Heteranthera Dubia Macm

Macroinvertebrate communities inhabiting an exotic, Myriophyllum spicatum, and a native, Heteranthera dubia macrophyte were studied from March 1999 to June 2000 in experimental ponds. Although macrophyte architecture explained some variation in macroinvertebrate abundance between the two macrophytes, most variation was explained by the sampling months. Total number of macroinvertebrates was found to be positively correlated with epiphyton biomass which differed significantly between the two plant types and among sampling months. Taxa richness did not vary between the two plant types. Chironomid larvae were the most abundant organisms and dominated by Apedilum elachistus on both plant communities. Annual production of five chironomid species was estimated by the size-frequency method. Production estimates (P) in g dry wt m-2 yr-1 of plant surface area for the predator Tanypodinae larvae were: Larsia decolarata, P= 0.77 and 0.67, Labrundinia virescens, P= 0.59 and 0.35 on M. spicatum and H. dubia, respectively. Larvae of Cricotopus sylvestris and Psectrocladius vernalis were collected from M. spicatum from March to mid-June. Production of C. sylvestris was found to be 0.46 g dry wt m-2, whereas it was 0.07 g dry wt m-2 for P. vernalis for this period. Apedilum elachistus exhibited the highest productivity: 9.9 g dry wt m-2 …
Date: May 2002
Creator: Balci, Pinar
System: The UNT Digital Library
A study of on-line use and perceived effectiveness of compliance-gaining in health-related banner advertisements for senior citizens. (open access)

A study of on-line use and perceived effectiveness of compliance-gaining in health-related banner advertisements for senior citizens.

This research investigated banner ads on the World Wide Web, specifically the types of messages used in those ads and the effectiveness of the ads as seen by their intended audience. The focus was on health-related banner advertisements targeting senior citizens. The study first sought to determine the frequency of appearance of those ads when classified into categories of compliance-gaining tactics provided by research scholars. Second, the study explored the relative perceived effectiveness among those categories. Two graduate students from a Central Texas university sorted text messages into predetermined compliance-gaining categories. Chi square tests looked for significant differences in the frequencies of banner ads in each category. Forty-five senior citizens from the Central Texas area completed surveys regarding the perceived effectiveness of a randomly ordered, randomly selected set of categorized banner ads. A repeated measures test attempted to determine whether some compliance-gaining strategies used in health-related banner ads were perceived as more effective than others. The hypothesis stated that there would be differences in frequencies of compliance-gaining strategies used among the compliance-gaining categories in health-related banner ads for senior citizens. The hypothesis was supported. The research question asked if some categories of compliance-gaining strategies used in health-related banner ads were …
Date: December 2002
Creator: Toon, Michelle Anne
System: The UNT Digital Library
Radio frequency propagation differences through various transmissive materials. (open access)

Radio frequency propagation differences through various transmissive materials.

The purpose of this research was to determine which of the commonly used wireless telecommunication site concealment materials has the least effect on signal potency. The tested materials were Tuff Span® fiberglass panels manufactured by Enduro Composite Systems, Lexan® XL-1 polycarbonate plastic manufactured by GE Corporation and Styrofoam™ polystyrene board manufactured by The Dow Chemical Company. Testing was conducted in a double electrically isolated copper mesh screen room at the University of North Texas Engineering Technology Building in Denton, Texas. Analysis of the data found no differences exist between the radio frequency transmissiveness of these products at broadband personal communication service frequencies. However, differences in the signal do exist with regards to the angle of incidence between the material and the transmitting antenna.
Date: December 2002
Creator: Ryan, Patrick L.
System: The UNT Digital Library
Redefining Beauty (open access)

Redefining Beauty

In an effort to continue the conceptual and aesthetic growth started in graduate school, I have produced a body of work dealing with the relation between the fragmentation of the figure and the self-perception of beauty. I produced twelve prints that have been exhibited at Cora Stafford Gallery. I have analyzed the body of work conceptually and formally and chose to discuss six pieces in a problem- in lieu-of-thesis. My work and book references informed the content of the paper. I divided it into three chapters; Introduction, Description of the Work, and the Conclusion. Within the body of the paper the paragraphs are sectioned into descriptions, methodology and intent of the six pieces. I went into detail of the process and content and addressed the questions posted in the Statement of Problem.
Date: May 2002
Creator: Perrin, Elvia
System: The UNT Digital Library
Effector Response of the Aspartate Transcarbamoylase From Wild Type  Pseudomonas Putida and a Mutant with 11 Amino Acids Deleted at the N-terminus of PyrB. (open access)

Effector Response of the Aspartate Transcarbamoylase From Wild Type Pseudomonas Putida and a Mutant with 11 Amino Acids Deleted at the N-terminus of PyrB.

Like its enteric counterpart, aspartate transcarbamoylase (ATCase) from Pseudomonas putida is a dodecamer of two different polypeptides. Unlike the enterics, the Pseudomonas ATCase lacks regulatory polypeptides but employs instead inactive dihydroorotases for an active dodecamer. Previous work showed that PyrB contains not only the active site but also the effector binding sites for ATP, UTP and CTP at its N-terminus. In this work, 11 amino acids were deleted from the N-terminus of PyrB and the ATCase with the truncated protein was expressed in E. coli pyrB- and purified. The wild type enzyme was similarly treated. Velocity-substrate plots without effectors gave Michaelis-Menten kinetics in all cases. Deleting 11 amino acids did not affect dodecameric assembly but altered effector responses. When carbamoylphosphate was varied, the mutant enzyme was inhibited by UTP while the wild type enzyme was activated 2-fold. When the aspartate was varied, CTP had no effect on the mutant enzyme but strongly inhibited the wild type enzyme.
Date: May 2002
Creator: Asfour, Hani
System: The UNT Digital Library
An Analysis of the Effectiveness of Computer Assisted Instruction in General Chemistry at an Urban University. (open access)

An Analysis of the Effectiveness of Computer Assisted Instruction in General Chemistry at an Urban University.

The science-major General Chemistry sequence offered at the University of Houston has been investigated with respect to the effectiveness of recent incorporation of various levels of computer technology. As part of this investigation, questionnaire responses, student evaluations and grade averages and distributions from up to the last ten years have been analyzed and compared. Increased use of web-based material is both popular and effective, particularly with respect to providing extra information and supplemental questions. Instructor contact via e-mail is also well-received. Both uses of technology should be encouraged. In contrast, electronic classroom presentation is less popular. While initial use may lead to improved grades and retention, these levels decrease quickly, possibly due to a reduction in instructor spontaneity.
Date: May 2002
Creator: McGuffey, Angela
System: The UNT Digital Library