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

Description: 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 predicted to be secreted to the extracellular matrix as a neutral isoform. The deduced amino acid sequence has 16 cysteine residues that are highly conserved in osmotin-like proteins and are important in stabilizing the three-dimensional structure seen in thaumatin, zeamatin, and PR5-d. The intronless cognate cotton genomic clone has two putative ethylene response elements (GCC boxes) found in other PR5 gene promoter regions, as well as several tentative promoter/enhancer elements possibly involved in spatial/temporal gene expression.
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Date: May 2002
Creator: Yoder, David W.
Partner: UNT Libraries

College Freshman Biology Two Semester Course: Integrating Deep Processing Teaching Techniques

Description: Development of a college level freshman biology course was undertaken in response to government reports that American students have fallen behind students of other countries in the area of the sciences. Teaching strategies were investigated to accomplish two objectives, to define essential academic material to include in the course and to investigate teaching techniques that would increase deep processing of the information. An active process that consisted of applying the cognitive information to solving problems or developing answers to questions was defined as critical thinking. Critical thinking was incorporated into the course by the use of case studies.
Date: May 2002
Creator: Blevins, Mary Jean
Partner: UNT Libraries

Coming in From the Cold: Integration into the European Union and Public Opinion on Democracy and the Market Economy in Central and Eastern Europe.

Description: The political economy transformations of the countries of Central and Eastern Europe have received a great deal of attention over the past decade. The focus of much research has been to examine the internal national reorientations of the countries with regard to the changes in political and economic conditions. The importance of the international reorientation of these countries toward Western Europe in general and the European Union in particular has been generally overlooked. This dissertation examines public opinion on the political and economic transformations within the framework of the direction of the international reorientations of the countries. The countries were divided into three categories, those that can be expected to be invited to join the European Union in the next enlargement, those that can be expected to join the European Union in a subsequent enlargement, and the countries not seeking European Union membership. Public opinion on democracy and the market economy and attitudinal factors that influence these opinions are compared in 16 countries in Central and Eastern Europe. The data are from the Central and East European Barometers 3-7 (1992 - 1996). The findings suggest that general opinions regarding satisfaction with democracy are not related to the status of the country seeking membership in the European Union while support from the market economy does differ. When examining attitudinal factors that are related to satisfaction with democracy and support for the market economy, differences emerged between the three categories of countries. These findings suggest that public opinion is in part shaped by the international orientations of the country and that changes in public opinion are important in understanding the political and economic transformation processes.
Date: May 2002
Creator: Zottarelli, Lisa K.
Partner: UNT Libraries

A Comparison of Aural and Visual Instructional Methodologies Designed to Improve the Intonation Accuracy of Seventh Grade Violin and Viola Instrumentalists.

Description: The purpose of the study was to compare two instructional methodologies designed to improve the intonation accuracy of seventh grade violin and viola instrumentalists. The collection of data was in regard to (1) instructional methodology: aural and aural/visual, (2) performance tasks: A, B, and C; (3) individual pitches (seven from each of the music tasks), and (4) differences between instrument groups: violin and viola. Sixty-eight seventh grade string students from three string classes of two middle schools were randomly assigned to two experimental groups: (a) aural and (b) aural/visual. The instructional period was implemented daily in ten-minute sessions during twenty days by the orchestra instructors of each school. A pretest-posttest format was used to determine if there were any changes in the subjects' intonation accuracy from prior to after the instructional phase was implemented, and if these changes could be attributed to any of the methodologies. The testing material used on both testing sessions included three performance tasks composed of seven notes each. Subjects were recorded on both testing occasions. The data were the scores of absolute pitch deviation, measured in cents from equal temperament, from the pre- and postest; these were treated with analysis of variance. The ANOVA on the posttest scores indicated a non-significant difference between the instructional methodologies in their effectiveness to improve the subjects' ability to play in tune.
Date: May 2002
Creator: Núñez, Mario Leoncio
Partner: UNT Libraries

A Comparison of Texas Pre-service Teacher Education Programs in Art and the 1999 National Art Education Association's Standards for Art Teacher Preparation

Description: Texas programs in pre-service art teacher preparation vary little. Since 1970, the National Art Education Association (NAEA) has created voluntary standards in hopes of decreasing variability among programs. In 1999, the NAEA published Standards for Art Teacher Preparation, outlining 20 content areas that art pre-service programs should provide their students. To obtain information on the implementation and the extent to which these 20 standards are being implemented, a questionnaire was sent to all programs in Texas. The 20 standards were the dependent variable for the study. The four independent variables used in this ex post facto study were: the size of the institution where the program exists; the number of full-time art faculty; the number of full-time art education faculty; and, the number of undergraduate art education students who graduated last year. The 20 standards or provisions were scored on a Lickert scale with six options: zero (not taught) to five (comprehensively taught). The response size (N = 23) was 47% of the state's 49 approved programs. The results from the survey suggest no significant difference among programs. However, the results showed a significant difference in the number of provisions taught between programs with no art educators and those with 1 to 3 art educators. One art educator seemed to increase the number of pedagogical provisions taught but did not increase the extent or enhance the degree to which each provision was taught. A comprehensively taught response to the NAEA provisions on the questionnaire was further investigated through analysis of catalog course descriptions and correspondence with participants. The results are estimated in credit hours and indicate that there may be a point where time on task decides the limit that constitutes a comprehensive preparation. Perspectives on content are discussed and regarded as too subjective to define comprehensive preparation. Comprehensive time ...
Date: May 2002
Creator: Breitenstein, Gary
Partner: UNT Libraries

Competency to Stand Trial: A Systematic Evaluation and Validation of the GCCT, MacCAT-CA, and ECST as Competency Measures

Description: Competency to stand trial cases constitute the largest percentage of forensic referrals for clinical psychologists. Furthermore, research suggests that the use of forensic measures facilitates the decisions of competency made by forensic examiners. This study investigated the construct validity of three competency measures: (a) the GCCT-MSH, (b) the MacCAT-CA, and (c) the ECST with 100 adult males incarcerated at the Tarrant County Jail in Fort Worth, TX. Construct validity was investigated via the use of a multitrait-multimethod research design for the three-prong conceptualization of the Dusky standard. Results indicated that current competency measures do an adequate job of assessing for factual understanding, but lack construct validity for two prongs: rational understanding and the ability to consult with counsel. In addition, the atypical presentation scales of the both GCCT and the ECST performed well at screening individuals for feigning. Finally, prediction of competency from clinical variables was also investigated. Psychotic symptoms and overall impairment were the strongest predictors of incompetency.
Date: May 2002
Creator: Grandjean, Nicole Rae
Partner: UNT Libraries

A Computational Study on 18+δ Organometallics

Description: The B3LYP density functional has been used to calculate properties of organometallic complexes of Co(CO)3 and ReBr(CO)3, with the chelating ligand 2,3-bisphosphinomaleic anhydride, in 19- and 18-electron forms. The SBKJC-21G effective core potential and associated basis set was used for metals (Co/Re) and the 6-31G* basis set was used for all other elements. The differences of bond angles, bond distances, natural atomic charges and IR vibrational frequencies were compared with the available experimental parameters. The differences between the 19- and 18-electron systems have been analyzed. The results reveal that the 19th electron is mostly distributed over the ligand of 2,3-bisphosphinomaleic anhydride, although partially localized onto the metal fragment in 1 and 2*. Two different methods, IR-frequencies and natural atomic charges, were used to determine the value of δ. Present computed values of δ are compared with available experimental values, and predictions are made for unknown complexes.
Date: May 2002
Creator: Yu, Liwen
Partner: UNT Libraries

Computer Supported Collaboration: Is the Transfer of Cognitive Structures Mediated by Mode of Communication?

Description: The objective of this study was to observe evidence of structural transfer among subjects in a group problem-solving activity and determine whether mode of collaborative technology or use of a priming agent affected the nature of transferred structures. Evidence for structural transfer is found in three theoretical perspectives: organizational ditransitive (linguistic) verb structures, adaptive structuration theory, and mental model transfer theory. Dependent variables included various grammatical structures and coefficients derived from pretest and posttest scores on David Kolb's Learning Styles Inventory, modified for the experiment. The combination of changes in grammatical frequencies and learning style may suggest that one or more media or the priming agent may affect structural transfer. Results indicate that groups using the GroupSystems™ collaborative technology produced less overall linguistic content than did subjects using a generic chat system, but employed more complex language as indicated by frequency of the organizational ditransitive verb structure. Also, subjects supplied with an organization chart (priming agent) during the group problem-solving session experienced greater change on the learning styles inventory than did those participating in the session without the chart. These findings suggest that mode of communication and use of priming agents may contribute positively or negatively to the transfer of structures among group members. Researchers, collaborative system designers, organizational leaders, trainers & educators, and frequent collaborative technology system end-users should be aware of these potential affects. Suggestions for future research are provided. Relationship of theoretical foundations of structural transfer to constructivism is discussed.
Date: May 2002
Creator: Bandy, Kenneth E.
Partner: UNT Libraries

The Construct Validity of Self-Reported Historical Physical Activity

Description: The purpose of this study was to determine the construct validity of self-reported historical walking, running, and jogging (WRJ) activity. The criterion measure was concurrent performance on a maximal treadmill test. Subjects completed a medical exam and treadmill test between the years 1976 and 1985, and completed a follow-up questionnaire in 1986. Questionnaire included an item that assessed WRJ for each year from 1976 through 1985. Data analysis included Spearman correlations, partial correlations, ANOVA, and ANCOVA. Results indicated self-reported historical WRJ can be assessed with reasonable validity when compared with concurrently measured treadmill performance, and there is no decay in the accuracy of this reporting for up to ten years in the past.
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Date: May 2002
Creator: Bowles, Heather R.
Partner: UNT Libraries

A Content Analysis of Reading Software Commercially Available for Pre-K to 3rd Grade Children.

Description: The purpose of this qualitative study was to investigate the content and characteristics of the currently available commercial reading software for Pre-K through third grade children. The design of the study was a content analysis. Based on the evaluation rubric established by the researcher, ten commercial reading software were selected to be analyzed. By reviewing and transcribing, the data were obtained, and then coded, categorized, and interpreted. The findings from the analysis revealed that all reading software programs offered exercised for practicing basic phonics skills; the alphabetic principle, letter-sound association, word knowledge, sentence building, and reading comprehension. Depending on the software developers, phonics-based practice was presented in two ways; separate skill-based practice emphasis and storybook-reading emphasis. All software programs utilized drill-and-practice, direct instruction and mastery learning methods and utilized gaming strategies to motivate and engage the learners. Multimedia technology was used to make the software more appealing. All reading software programs were developed on the perspectives that view learning to read as the continuum of a child's oral language development and background experience about words. It is recommended that parents and teachers review and select the software based on reliable information sources, use the software as supplementary practice based on the learning objectives identified and individual student needs.
Date: May 2002
Creator: Nakjan, Sutat
Partner: UNT Libraries

A Correlative Study of Gender and Social Style.

Description: This study examines the concepts of social style and gender to determine if a relationship exists between the two constructs. The hypotheses suggested a direct relationship between the categories of the BSRI (masculine, feminine, androgynous, and undifferentiated) and the Social Style Analysis (driver, amiable, expressive, and analytical). Ninety-four participants completed two self-report surveys. Chi-square analysis performed on the data found a significant relationship between feminine and amiable as well as androgynous and expressive. While the analysis suggested that masculine/driver and undifferentiated/analytical were not independent, the relationship found was not significant.
Date: May 2002
Creator: Gross, Amanda
Partner: UNT Libraries

The Crater of Diamonds: A History of the Pike County, Arkansas, Diamond Field, 1906-1972

Description: The first diamond mine in North America was discovered in 1906 when John W. Huddleston found two diamonds on his farm just south of Murfreesboro in Pike County, Arkansas. Experts soon confirmed that the diamond-bearing formation on which Huddleston made his discovery was the second largest of its kind and represented 25 percent of all known diamond-bearing areas in the world. Discovery of the field generated nearly a half century of speculative activity by men trying to demonstrate and exploit its commercial viability. The field, however, lacked the necessary richness for successful commercial ventures, and mining was eventually replaced in the early 1950s by tourist attractions that operated successfully until 1972. At that time the State of Arkansas purchased the field and converted it to a state park. Thus this work tell the rich and complicated story of America'a once and only diamond field, analyzes the reasons for the repeated failures of efforts to make it commercially viable, and explains how it eventually succeeded as a tourist venture.
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Date: May 2002
Creator: Henderson, John C.
Partner: UNT Libraries

Detecting the Presence of Disease by Unifying Two Methods of Remote Sensing.

Description: There is currently no effective tool available to quickly and economically measure a change in landmass in the setting of biomedical professionals and environmental specialists. The purpose of this study is to structure and demonstrate a statistical change-detection method using remotely sensed data that can detect the presence of an infectious land borne disease. Data sources included the Texas Department of Health database, which provided the types of infectious land borne diseases and indicated the geographical area to study. Methods of data collection included the gathering of images produced by digital orthophoto quadrangle and aerial videography and Landsat. Also, a method was developed to identify statistically the severity of changes of the landmass over a three-year period. Data analysis included using a unique statistical detection procedure to measure the severity of change in landmass when a disease was not present and when the disease was present. The statistical detection method was applied to two different remotely sensed platform types and again to two like remotely sensed platform types. The results indicated that when the statistical change detection method was used for two different types of remote sensing mediums (i.e.-digital orthophoto quadrangle and aerial videography), the results were negative due to skewed and unreliable data. However, when two like remote sensing mediums were used (i.e.- videography to videography and Landsat to Landsat) the results were positive and the data were reliable.
Date: May 2002
Creator: Reames, Steve
Partner: UNT Libraries

Determination of the Shelf Life of Aluminum Electrolytic Capacitors.

Description: The aluminum electrolytic capacitor is used extensively in the electric utility industry. A factor limiting the storage of spare capacitors is the integrity of the aluminum oxide dielectric, which over time breaks down contributing to a shelf life currently estimated at one nuclear power electric generating station to be approximately five years. This project examined the electrical characteristics of naturally aged capacitors of several different styles to determine if design parameters were still within limits. Additionally, the effectiveness of a technique known as “Reforming” was examined to determine its impact on those characteristics.
Date: May 2002
Creator: Wynne, Edward McFaddin
Partner: UNT Libraries

Dimensions in Random Constructions.

Description: We consider random fractals generated by random recursive constructions, prove zero-one laws concerning their dimensions and find their packing and Minkowski dimensions. Also we investigate the packing measure in corresponding dimension. For a class of random distribution functions we prove that their packing and Hausdorff dimensions coincide.
Date: May 2002
Creator: Berlinkov, Artemi
Partner: UNT Libraries

Dna Profiling of Captive Roseate Spoonbill (Ajaia Ajaja) Populations As a Mechanism of Determining Lineage in Colonial Nesting Birds.

Description: Roseate spoonbills are colonial nesting birds with breeding grounds extending from the United States Gulf coast to the pampas of Argentina. The U.S. population suffered a severe bottleneck from 1890 to 1920. The population's recovery was slow and partially credited to migrations from Mexican rookeries, but a gene pool reduction would be expected. Five polymorphic Spoonbill autosomal short tandem repeat (STR) loci [three (GAT)n, one (AAAG)n and one (GT)n] and one Z/W-linked microsatellite exhibiting sex-specific dimorphism were isolated and characterized. The Z/W-linked STR locus accurately confirmed the sex of each bird. Allelic profiles for 51 spoonbills obtained from Dallas (Texas), Fort Worth (Texas) and Sedgwick County (Kansas) zoos revealed a non-continuous distribution of allele frequencies, consistent with the effects of a population bottleneck. Allelic frequencies also differed significantly between the isolated zoo populations. Although extra-pair copulations were suspected and difficult to document, zoos commonly used observational studies of mating pairs to determine familial relationships among adults and offspring. STR parentage analysis of recorded family relationships excluded one or both parents in 10/25 cases studied and it was further possible to identify alternative likely parents in each case. Mistaken familial relationships quickly lead to the loss of genetic variability in captive populations. Here, a decreased heterozygosity (HO) in 2nd generation captive-bred birds was observed at 3 out of 4 loci evaluated. Although these results could not be statistically validated because of the small number of individuals available for study (15 wild birds with no offspring vs. eight 2nd generation captive birds), they are considered biologically important, as decreased HO is an indicator of inbreeding and this apparent decrease occurred within two generations of removal from the wild. Collectively, the evidence obtained from this study suggests that captive spoonbill populations are experiencing rapid loss of diversity from an already depleted wild gene ...
Date: May 2002
Creator: Sawyer, Gregory M.
Partner: UNT Libraries

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

Description: 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 yr-1 of plant surface area on M. spicatum, and 8.5 g dry wt m-2 yr-1 on H. dubia. These production estimates are among the highest production values reported for a single species. Additionally, post-ovipositing development times for five chironomid species collected from Myriophyllum and Heteranthera were determined. Three different temperatures (15°, 20° and 25°C) were chosen to rear eggs under 12L: 12D photoperiod. Egg development times ranged between 1-4 days. Larval development times ranged from 44 days at 20°C for Tanypus neopunctipennis to as few as 9 days at 20°C for Larsia decolorata.
Date: May 2002
Creator: Balci, Pinar
Partner: UNT Libraries

The Effect of Average Grain Size on Polycrystalline Diamond Films

Description: The work function of hydrogen-terminated, polycrystalline diamond was studied using ultraviolet photoelectron spectroscopy. Polycrystalline diamond films were deposited onto molybdenum substrates by electrophoresis for grain sizes ranging from 0.3 to 108 microns. The work function and electron affinity were measured using 21.2 eV photons from a helium plasma source. The films were characterized by x-ray photoelectron spectroscopy to determine elemental composition and the sp2/sp3 carbon fraction. The percentage of (111) diamond was determined by x-ray diffraction, and scanning electron microscopy was performed to determine average grain size. The measured work function has a maximum of 5.1 eV at 0.3 microns, and decreases to 3.2 eV at approximately 4 microns. Then the work function increases with increasing grain size to 4.0 eV at 15 microns and then asymptotically approaches the 4.8 eV work function of single crystal diamond at 108 microns. These results are consistent with a 3-component model in which the work function is controlled by single-crystal (111) diamond at larger grain sizes, graphitic carbon at smaller grain sizes, and by the electron affinity for the intervening grain sizes.
Date: May 2002
Creator: Abbott, Patrick Roland
Partner: UNT Libraries

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.

Description: 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
Partner: UNT Libraries

The Effects of Cesium Deposition and Gas Exposure on the Field Emission Properties of Single Wall and Multiwall Carbon Nanotubes

Description: The effects of Cs deposition on the field emission (FE) properties of single-walled carbon nanotube (SWNT) bundles were studied. In addition, a comparative study was made on the effects of O2, Ar and H2 gases on the field emission properties of SWNT bundles and multiwall carbon nanotubes (MWNTs). We observed that Cs deposition decreases the turn-on field for FE by a factor of 2.1 - 2.9 and increases the FE current by 6 orders of magnitude. After Cs deposition, the FE current versus voltage (I-V) curves showed non-Fowler-Nordheim behavior at large currents consistent with tunneling from adsorbate states. At lower currents, the ratio of the slope of the FE I-V curves before and after Cs deposition was approximately 2.1. Exposure to N2 does not decrease the FE current, while exposure to O2 decreases the FE current. Our results show that cesiated SWNT bundles have great potential as economical and reliable vacuum electron sources. We find that H2 and Ar gases do not significantly affect the FE properties of SWNTs or MWNTs. O2 temporarily reduces the FE current and increases the turn-on voltage of SWNTs. Full recovery of these properties occurred after operation in UHV. The higher operating voltages in an O2 environment caused a permanent decrease of FE current and increase in turn-on field of MWNTs. The ratios of the slopes before and after O2 exposure were approximately 1.04 and 0.82 for SWNTs and MWNTs, respectively. SWNTs compared to MWNTs would appear to make more economical and reliable vacuum electron sources.
Date: May 2002
Creator: Wadhawan, Atul
Partner: UNT Libraries

The Effects of Non-differential Reinforcement and Differential Reinforcement on Problem Behaviors and Accuracy of Responding of Autistic Children.

Description: The effects of non-differential reinforcement and differential reinforcement on problem behaviors and accuracy of responding of autistic children was examined. In experiment 1, one child with autism participated, and in experiment 2, two children with autism participated. In the non-differential reinforcement condition both prompted and unprompted responses were reinforced. In the differential reinforcement condition only unprompted responses were reinforced. Overall, problem behaviors were more frequent in the non-differential reinforcement condition. In experiment 1, accuracy was higher in the differential reinforcement condition, while experiment 2 showed inconclusive results with regards to accuracy. It is concluded that non-differential reinforcement can decrease problem behaviors in teaching situations, but may not be sufficient to ensure acquisition of target tasks.
Date: May 2002
Creator: Ingvarsson, Einar Thor
Partner: UNT Libraries

The Effects of Selective Serotonin Reuptake Inhibitors (Ssri) on Auditory Measures in Clinically Depressed Subjects.

Description: The purpose of this study was to investigate the relationship between selective serotonin reuptake inhibitor (SSRI) medication on auditory skills in clinically depressed subjects. Experimental subjects prescribed an SSRI were tested in a medicated and an unmedicated condition, and the test results were compared. Furthermore, the experimental group was compared with a control group consisting of normal subjects. Test measures included pure tone audiometry, tympanometry, acoustic reflex thresholds, and auditory electrophysiologic measures such as auditory brainstem and auditory late responses. An assessment scale for depression (Beck Depression Inventory-II) was also used. Results indicated statistically significant differences for the BDI-II between the control and experimental groups for both conditions. Electrophysiologic measures indicated a significantly shorter latency for auditory late potential P1 at 55 dBnSL, and a significantly larger amplitude at 45 dBnSL for the N1/P2 component for the unmedicated group. Although the other measures showed trends, they did not reach significance.
Date: May 2002
Creator: Goodale, Elizabeth S.
Partner: UNT Libraries

The Effects of Selective Serotonin Reuptake Inhibitors (SSRI) on Auditory Measures in Women

Description: This study examined the relationship between selective serotonin reuptake inhibitor (SSRI) medication and auditory measures in clinically depressed women. Experimental subjects were tested in both a medicated and unmedicated condition. Experimental subjects were compared to a normal control group; additionally intrasubject comparison was made within the experimental group. Test measures included: audiometry, tympanometry, otoacoustic emissions, uncomfortable loudness level, masking level difference, SCAN-A, Synthetic Sentence Identification (SSI), and the low predictability section of the Revised Speech in noise (RSPIN). The unmedicated group scored significantly less favorably than the control group on the following tests; SCAN-A (composite, filtered words, and auditory figure ground), R-SPIN (0MCR condition in both the right and left ears). Additionally, the unmedicated group scored significantly less favorably than the medicated group on the SSI (-20MCR condition right ear only) and of the R-SPIN (0MCR condition right ear only). Other test measures indicated consistent trends but did reach significance.
Date: May 2002
Creator: Briley, Kelly Anne
Partner: UNT Libraries

Effects of Sublethal Copper Exposure on Escape Behavior and Growth of Rana pipiens Tadpoles

Description: This research is designed to test how sublethal exposure to copper affects tadpole predator-escape behavior and how quickly tadpoles recover. After exposure, tadpoles were separated. Escape behavior was recorded for two-thirds of exposed tadpoles while one-third of the exposed population was measured weekly to determine growth and recovery. Control tadpoles were consumed within 15 minutes whereas those exposed to higher concentrations were consumed at a slower rate, which does not support the hypotheses. Although the rate of predation was lower, tadpoles exposed to higher Cu concentrations were on average, 1.47 cm in total body length. Those exposed to 0.93 mg/L averaged 0.86 cm. After being placed into clean water, treatment tadpoles recovered after 20 days.
Date: May 2002
Creator: Redick, Melinda
Partner: UNT Libraries