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Temporally Correct Algorithms for Transaction Concurrency Control in Distributed Databases

Description: Many activities are comprised of temporally dependent events that must be executed in a specific chronological order. Supportive software applications must preserve these temporal dependencies. Whenever the processing of this type of an application includes transactions submitted to a database that is shared with other such applications, the transaction concurrency control mechanisms within the database must also preserve the temporal dependencies. A basis for preserving temporal dependencies is established by using (within the applications and databases) real-time timestamps to identify and order events and transactions. The use of optimistic approaches to transaction concurrency control can be undesirable in such situations, as they allow incorrect results for database read operations. Although the incorrectness is detected prior to transaction committal and the corresponding transaction(s) restarted, the impact on the application or entity that submitted the transaction can be too costly. Three transaction concurrency control algorithms are proposed in this dissertation. These algorithms are based on timestamp ordering, and are designed to preserve temporal dependencies existing among data-dependent transactions. The algorithms produce execution schedules that are equivalent to temporally ordered serial schedules, where the temporal order is established by the transactions' start times. The algorithms provide this equivalence while supporting currency to the extent out-of-order commits and reads. With respect to the stated concern with optimistic approaches, two of the proposed algorithms are risk-free and return to read operations only committed data-item values. Risk with the third algorithm is greatly reduced by its conservative bias. All three algorithms avoid deadlock while providing risk-free or reduced-risk operation. The performance of the algorithms is determined analytically and with experimentation. Experiments are performed using functional database management system models that implement the proposed algorithms and the well-known Conservative Multiversion Timestamp Ordering algorithm.
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Date: May 2001
Creator: Tuck, Terry W.

Teen ages: Youth market romance in Hollywood teen films of the 1980s and 1990s

Description: This thesis examines the differences between teen romantic comedy films marketed to Generation X teenagers in the 1980s and Generation Y teenagers in the 1990s, focusing on the presentation of gender roles, consumptive behavior, and family. The 1980s films are discussed within the social context of the Reagan era and the conservatism of the New Right. The 1990s films are examined as continuing a conservative sensibility, but they additionally posit consumption as instrumental to achieving an idealized romance. Romantic comedy is traditionally a conservative genre, but these films illustrate female liberation through consumption. The source of difference between the cycles of teen romantic comedy is attributed to the media's attempt to position Generation Y teenagers as ideal consumers.
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Date: May 2001
Creator: Murphy, Caryn E.

Interactions of Clean and Sulfur-modified Reactive Metal Surfaces with Aqueous Vapor and Liquid Environments : A Combined Ultra-high Vacuum/electrochemistry Study

Description: The focus of this research is to explore the molecular-level interactions between reactive metal surfaces and aqueous environments by combined ultra-high vacuum/electrochemistry (UHV-EC) methodology. The objectives of this work are to understand (1) the effects of sulfate ions on the passivity of metal oxide/hydroxide surface layer, (2) the effects of sulfur-modification on the evolution of metal oxide/hydroxide surface layer, and (3) the effects of sulfur adsorbate on cation adsorption at metal surfaces.
Date: May 1998
Creator: Lin, Tien-Chih, 1966-

Formalization of Collection Development in Selected Medium-sized Academic Libraries

Description: The degree of formalization of collection development(the dependent variable) in selected medium-sized academic libraries and six independent variables believed to be related to the dependent variable were examined. The formalization of collection development was measured by an index of five dimensions. The six independent variables examined were age of the library, number of graduate degrees offered by the parent institution, estimated years of growth potential in terms of available shelf space, attitude of the library director toward cooperation, number of memberships held by the library in cooperative endeavors, and percentage of increase in the materials budget, from 1972 to 1982.
Date: December 1984
Creator: Harvill, Melba S.

Masculine Role Conflict in Gay Men: Mediation of Psychological Well-Being and Help-Seeking Behaviors

Description: Gender role issues have been an integral part of psychology since the 1970s. More recently, theories and research have surfaced concerning the issues of maleness in our society. Most of these theories focus on masculine gender role and how it affects men in various ways, e.g., their psychological well-being, substance use, relational abilities, and help-seeking behaviors. One area of maleness that has consistently been left out of the Masculine Role Conflict (MRC) debate is that of homosexuality. As a gay man develops, he finds himself at odds with society over something that he experiences biologically as normal and appropriate. It is the contention of this paper that MRC is an issue related to psychological distress among gay men and not psychological weakness in gay men, per se.
Date: August 1998
Creator: Simonsen, Gregory

Isolation and analysis of cotton genomic clones encompassing a fatty acid desaturase (FAD2) gene

Description: Polyunsaturated fatty acids are major structural components of plant chloroplast and endoplasmic reticulum membranes. Two fatty acid desaturases (designated FAD2 and FAD3) desaturate 75% of the fatty acids in the endoplasmic reticulum. The w -6 fatty acid desaturase (FAD2) may be responsible for cold acclimation response, since polyunsaturated phospholipids are important in helping maintain plant viability at lowered temperatures. To study regulation of FAD2 gene expression in cotton, a FAD2 gene was isolated from two genomic libraries using an Arabidopsis FAD2 hybridization probe and a cotton FAD2 5¢ -flanking region gene-specific probe, respectively. A cotton FAD2 gene was found to be in two overlapping genomic clones by physical mapping and DNA sequencing. The cloned DNA fragments are identical in size to cotton FAD2 genomic DNA fragments shown by genomic blot hybridization. The cotton FAD2 coding region has 1,155 bp with no introns and would encode a putative polypeptide of 384 amino acids. The cotton FAD2 enzyme has a high identity of 75% with other plant FAD2 enzymes. The enzyme has three histidine-rich motifs that are conserved in all plant membrane desaturases. These histidine boxes may be the iron-binding domains for reduction of oxygen during desaturation. To confirm that this FAD2 enzyme is functional, a plasmid construct containing the cotton FAD2 coding region was transformed into Saccharomyces cerevisiae. The transformed yeast cells were able to catalyze the conversion of oleic acid (C18:1) into linoleic acid (C18:2). The FAD2 gene contains an intron of 2,967 bp in its 5¢ -flanking region, 11 bp upstream from the initiation codon. The intron could be essential for transcriptional regulation of FAD2 gene expression. Several putative promoter elements occur in the 5¢ -flanking region of this gene. A potential TATA basal promoter element occurs at 41 bp upstream from the cap site. Two presumptive helix-loop-helix (bHLH) ...
Date: May 2001
Creator: Kongcharoensuntorn, Wisatre

The Effect of Self Concept and Various Conceptual and Physical Practice Methods Upon the Performance of a Selected Basketball Motor Skill

Description: The problem investigated was the effect of various methods of conceptual, physical, and conceptual-physical practice procedures upon performance of the basketball motor skill of foul shooting. The sub-problem under investigation was the effect of self-concept upon the performance of foul shooting.
Date: May 1971
Creator: Lewis, Raymond Lee

Electron Density and Collision Frequency Studies Using a Resonant Microwave Cavity as a Probe

Description: Electron densities and collision frequencies were obtained on a number of gases in a dc discharge at low pressures (0.70-2mm of Hg). These measurements were performed by microwave probing of a filament of the dc discharge placed coaxially in a resonant cavity operating in a TM₀₁₀ mode. The equipment and techniques for making the microwave measurements employing the resonant cavity are described. One of the main features of this investigation is the technique of differentiating the resonance signal of the loaded cavity in order to make accurate measurements of the resonant frequency and half-power point frequencies.
Date: May 1973
Creator: Freeman, Ronald Harold

The Effect of Giving Class Time for Reading on the Reading Achievement of Fourth Graders and the Effect of Using a Computer-Based Reading Management Program on the Reading Achievement of Fifth Graders

Description: This study investigated the problem that educators have throughout the state of Texas. The problem educators have is that reading scores continue to fall short of state expectations. This study investigated the effectiveness of 90 minutes of class time given for reading to students who use the Electronic Bookshelf Program and the effectiveness of the Electronic Bookshelf Program, which is being sold to school districts throughout the nation. The literature review focused on the effectiveness of independent reading on reading achievement, and the effectiveness of using computer-based reading programs to increase reading achievement.
Date: May 1998
Creator: Peters, Rochelle

Chemical Equilibria in Binary Solvents

Description: Dissertation research involves development of Mobile Order Theory thermodynamic models to mathematically describe and predict the solubility, spectral properties, protonation equilibrium constants and two-phase partitioning behavior of solutes dissolved in binary solvent mixtures of analytical importance. Information gained provide a better understanding of solute-solvent and solvent-solvent interactions at the molecular level, which will facilitate the development of better chemical separation methods based upon both gas-liquid and high-performance liquid chromatography, and better analysis methods based upon complexiometric and spectroscopic methods. Dissertation research emphasizes chemical equilibria in systems containing alcohol cosolvents with the understanding that knowledge gained will be transferable to more environmentally friendly aqueous-organic solvent mixtures.
Date: August 1997
Creator: McHale, Mary E. R.

Susceptibility of College Students to Alcohol Abuse and Alcohol Related Problems: the Impact of Family Environmental Factors

Description: The purpose of this study was to examine the impact of parental divorce, level of family conflict, and family history of alcoholism on the alcohol use patterns of college students. Gender differences were also explored. Multivariate Analysis of Variance revealed mixed results. Parental marital status was found to have no significant effect on college students' alcohol behavior. High family conflict had a significant impact on both level of current alcohol use and level of alcohol related problems. A positive family history of alcoholism was found to have effects on the level of alcohol related problems encountered by students. Gender played a significant role, with males reporting higher levels of alcohol-related problems. No significant interactions were found. Results, contributions and limitations of the study are discussed.
Date: December 1998
Creator: Blue, James M. (James Michael)

Creating a Mythistory: Texas Historians in the Nineteenth Century

Description: Many historians have acknowledged the temptation to portray people as they see themselves and wish to be seen, blending history and ideology. The result is "mythistory." Twentieth century Texas writers and historians, remarking upon the exceptional durability of the Texas mythistory that emerged from the nineteenth century, have questioned its resistance to revision throughout the twentieth century. By placing the writing of Texas history within the context of American and European intellectual climates and history writing generally, from the close of the eighteenth century to the beginning of the twentieth, it is possible to identify a pattern that provides some insight into the popularity and persistence of Texas mythistory.
Date: August 1998
Creator: McLemore, Laura Lyons, 1950-

Out with the Old? Voting Behavior and Party System Change in Canada and the United States in the 1990's

Description: This study has attempted to explain the dramatic challenges to the existing party system that occurred in Canada and the United States in the early 1990s. The emergence of new political movements with substantial power at the ballot box has transformed both party systems. The rise of United We Stand America in the United States, and the Reform Party in Canada prompts scholars to ask what forces engender such movements. This study demonstrates that models of economic voting and key models of party system change are both instrumental for understanding the rise of new political movements.
Date: December 1997
Creator: Rapkin, Jonathan D.

Participation in Student Financial Aid Programs during the Freshman Year and Persistence in a Private University

Description: The study determined the overall persistence rate of first-time full-time entrants into a mid-sized private university during the fall semesters 1989 to 1991 to the 2nd year (1990 to 1992). The study compared the retention rate of recipients and nonrecipients of a variety of financial aid programs. Included is a comparison of groups receiving various types of financial assistance and whether or not there are differences between the groups with respect to types of assistance, gender, ethnicity (African American, Hispanic, Anglo), high school grade point average, and national test scores (SAT, ACT). The types of assistance studied were categorized by academic scholarships, university-operated student employment, need-based grants, activity awards, entitlements, and loans. The question of whether renewal, elimination, or reduction in assistance relates to retention was also studied.
Date: August 1997
Creator: Munson, Leo W.

Unique applications of cultured neuronal networks in pharmacology, toxicology, and basic neuroscience

Description: This dissertation research explored the capabilities of neuronal networks grown on substrate integrated microelectrode arrays in vitro with emphasis on utilizing such preparations in three specific application domains: pharmacology and drug development, biosensors and neurotoxicology, and the study of burst and synaptic mechanisms. Chapter 1 details the testing of seven novel AChE inhibitors, demonstrating that neuronal networks rapidly detect small molecular differences in closely related compounds, and reveal information about their probable physiological effects that are not attainable through biochemical characterization alone. Chapter 2 shows how neuronal networks may be used to classify and characterize an unknown compound. The compound, trimethylol propane phosphate (TMPP) elicited changes in network activity that resembled those induced by bicuculline, a known epileptogenic. Further work determined that TMPP produces its effects on network activity through a competitive inhibition of the GABAA receptor. This demonstrates that neuronal networks can provide rapid, reliable warning of the presence of toxic substances, and from the manner in which the spontaneous activity changes provide information on the class of compound present and its potential physiological effects. Additional simple pharmacological tests can provide valuable information on primary mechanisms involved in the altered neuronal network responses. Chapter 3 explores the effects produced by a radical simplification of synaptic driving forces. With all synaptic interactions pharmacologically limited to those mediated through the NMDA synapse, spinal cord networks exhibited an extremely regular burst oscillation characterized by a period of 2.9 ± 0.3 s, with mean coefficients of variation of 3.7, 4.7, and 4.9 % for burst rate, burst duration, and inter-burst interval, respectively (16 separate cultures). The reliability of expression of this oscillation suggests that it may represent a fundamental mechanism of importance during periods of NMDA receptor dominated activity, such as embryonic and early postnatal development. NMDA synapse mediated activity produces a precise ...
Date: May 2001
Creator: Keefer, Edward W.

Empirical Research of Decision-making Effectiveness When Using Differing Presentation Formats Under Varying Decision Tasks

Description: The purpose of this research was to determine if presentation format, given a particular task to be performed, would affect the decision-making process of financial decision makers. The problem motivating this study is the potential for managers to make inefficient decisions when they use reports which are presented inappropriately for a given task.
Date: December 1988
Creator: Hard, Nancy J. (Nancy Jean)

The Use of an Academic Library by University Students

Description: Academic librarians have for a number of decades been interested in understanding more about how and why students use libraries. This study contributes to that area of library administration by focusing on nine factors thought to be associated with student use of academic libraries.
Date: August 1988
Creator: Harrell, Charles B.

A Comparison of the Desirability and Feasibility of Accountability Measures as Perceived by Public School Administrators and Teachers

Description: This study had three main purposes. The first was to determine the perceptions of public school administrators toward desirability and toward feasibility of accountability items. The second was to determine the perceptions of public school teachers toward desirability and toward feasibility of accountability items. The third was to compare the perceptions of administrators with those of teachers and to indicate areas where they seemed to be in agreement or disagreement.
Date: May 1973
Creator: Kiamie, Robert A.

Light Spectra Distributions in Temperate Conifer-Forest Canopy Gaps, Oregon and in Tropical Cloud-Forest Canopy, Venezuela

Description: Light spectra distributions were measured in two different montane forests: temperate and tropical. Spectral light measurements were made in different sized canopy gaps in the conifer forest at H. J. Andrews Experimental Forest in Oregon, USA. Researchers at Oregon State University created these gaps of 20 m, 30 m, and 50 m in diameter. In the tropical cloud forest, spectral light measurements were made in two plots that were permanently established at La Mucuy Parque Nacional in Venezuela, in collaboration with researchers at Universidad de Los Andes. In both studies, spectra and distributions of physiologically active light were analyzed: red, far-red, R/FR ratio, and blue light.
Date: December 1997
Creator: Monteleone, Susan Elaine