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The Effects of Hypothermia on the Release of Cardiac Enzymes

Description: The myocardium is known to release CPK, LDH1 , and GOT in response to ischemia as a result of myocardial infarction. This study was designed to induce the release of cardiac enzymes without adversely effecting the myocardium by perfusion hypothermia, thereby suggesting that these enzymes are not as specific in the diagnosis of myocardial infarction as once thought. Hypothermia was by in vivo perfusion of the left anterior descending coronary artery. Enzyme activity was measured from sera samples spectrophotometrically and electrophoretically. Significant CPK and LDH1 increases were observed in animals perfused between 25 and 19 C. These results indicate that, while heart function remained unchanged, an alteration occurred in the membrane integrity of the myocardial cells.
Date: August 1977
Creator: Strawn, William B.
Partner: UNT Libraries

The Effects of Illustrations on a Context Method of Learning Reading Vocabulary for Fourth-Grade Students

Description: The purpose of this study was to compare the effectiveness of a context approach to learning reading vocabulary with the effectiveness of the context approach accompanied by illustrations. Subjects were 152 fourth graders from 19 reading classes in 8 elementary schools. Materials included illustrated and nonillustrated vocabulary cards, a researcher-made multiple-choice instrument, and a widely used achievement test, which was used to identify the subjects as good or poor readers. The researcher made instrument was administered as a pretest during the first week of the study. Forty-eight vocabulary words were taught during the second through fifth weeks. The instrument was given again as a posttest during week six and as a delayed posttest during week twelve. Results were analyzed with the analysis of covariance procedure.
Date: August 1983
Creator: Nease, Charles
Partner: UNT Libraries

The Effects of Imaging Ability, Guided Imagery, and Source of Themes on Interview Verbal Behavior

Description: Eighty four female undergraduate students participated in a psychotherapy analog study to determine the effects of imagery ability, guided imagery therapy treatments, and personal versus supplied constructs upon self-disclosure variables in a 2 x 3 x 2 Anova design, with repeated measures on the final factor. Dependent variables were measured by reaction time, total talk time, speech duration, silence quotient, and Doster's (1971) Self-Disclosure Rating Scale. Subjects were divided into two imagery ability levels on the basis of local mean scores on Sheehan's (1967) modification of Betts' (1909) Questionnaire upon Mental Imagery. Three treatment procedures were employed: a guided focal imagery treatment, which encouraged imagery involving the interpersonal topics to be discussed, a guided relaxation imagery treatment which used standard sensory relaxation scenes, and a treatment which imparted ambiguous instructions. The final factor was repeated measures of the eight negative topics the subjects were asked to discuss. Four were chosen from the subjects' Role Construct Repertory Test grid (Kelly, 1955; Landfield, 1971), and four were selected from the Semantic Differential (Snider & Osgood, 1969).
Date: December 1985
Creator: Wixson, Sandra Werre
Partner: UNT Libraries

Effects of Immaturity on Juveniles’ Miranda Comprehension and Reasoning

Description: Over the last several decades, researchers have documented how impaired reasoning by adult offenders impeded the intelligent waiver of Miranda rights. Logically, it stands to reason that juveniles – who are developmentally less mature and have less life experience than their adult counterparts – would possess even greater impairment, thereby heightening their risk for invalid Miranda waivers. Juvenile Miranda research supports this notion; with some researchers finding that psychosocial maturity, among other factors, affect a juvenile’s understanding of their rights. Yet, relatively few studies have examined its relation to Miranda reasoning and decision-making. Thus, the current study investigated the specific role of maturity in juveniles’ Miranda comprehension and reasoning. Participants included 236 legally-involved juveniles recruited from either a juvenile detention center or a juvenile justice alternative education program. The effects of psychosocial maturity were examined on a variety of Miranda-related measures and assessed a broad range of Miranda abilities. It was found that, in general, immature juveniles performed more poorly on all Miranda measures as compared to their mature counterparts. However, the impact of maturity varied considerably depending on the ability. Specifically, maturity was most important in the context of Miranda reasoning. As a novel addition to the literature, the current study also investigated the effects of developmental timing on maturity (i.e., immaturity-delayed versus immaturity-expected) on Miranda abilities.
Date: August 2015
Creator: Sharf, Allyson J.
Partner: UNT Libraries

Effects of Implementing a Competency-Based Performance Management System on Measures of Sales Performance

Description: Use of competency models has exploded in recent years. Unfortunately, the empirical research to validate such systems is scarce. This study explores the relationship between Competency-based Performance Management Systems and sales performance to determine whether the use of these systems increases performance. Performance data from sales representatives in a medical products company were examined to determine changes in performance following the introduction of the Competency-based Performance Management System (N=64). Correlations with performance were obtained for each competency dimension to determine if any factors were highly correlated with performance and if state-factors were more positively correlated with performance than trait-factors (N=66). The study found no significant relationship between implementation of a Competency-based Performance Management System and sales performance. Also state-factors were not more positively correlated with sales performance than trait-factors.
Date: May 2000
Creator: Lynch, Ronald
Partner: UNT Libraries

The Effects of Inbreeding on Fitness Traits in the Critically Endangered Attwater’s Prairie-chicken

Description: The goals of captive breeding programs for endangered species include preserving genetic diversity and avoiding inbreeding. Typically this is accomplished by minimizing population mean kinship; however, this approach becomes less effective when errors in the pedigree exist and may result in inbreeding depression, or reduced survival. Here, both pedigree- and DNA-based methods were used to assess inbreeding depression in the critically endangered Attwater’s prairie-chicken (Tympanuchus cupido attwateri). Less variation in the pedigree-based inbreeding coefficients and parental relatedness values were observed compared to DNA-based measures suggesting that errors exist in the pedigree. Further, chicks identified with high parental DNA-based relatedness exhibited decreased survival at both 14- and 50-days post-hatch. A similar pattern was observed in later life stages (> 50 days post-hatch) with birds released to the wild; however, the pattern varied depending on the time post-release. While DNA-based inbreeding coefficient was positively correlated with mortality to one month post-release, an opposite pattern was observed at nine months suggesting purging of deleterious alleles. I also investigated whether immunocompetence, or the ability to produce a normal immune response, was correlated with survival; however, no significant correlation was observed suggesting that inbreeding was a more important factor influencing survival. Pairing individuals for breeding by minimizing DNA-based parental relatedness values resulted in a significant increase in chick survival. This study highlights the importance of using DNA-based methods to avoid inbreeding depression when errors exist in the pedigree.
Date: August 2014
Creator: Hammerly, Susan C.
Partner: UNT Libraries

The Effects of Incentive and Frustrative Cues on the Acquisition of an Alleyway Running Response in Rats

Description: The motivational properties of Longstreth's (1970) definitions of incentive and frustrative cues were tested using 32 rats in a two phase straight alleyway experiment. During pretraining, incentive cue Ss were presented a visual cue prior to reinforcement; frustrative cue Ss experienced the visual cue simultaneously with reinforcement. Ss encountered the same cue in mid-alley during 40 CRF training trials. Significant inhibition developed as frustrative cue Ss passed through the cue and postcue segments. Significant incentive effects occurred midway through training only in the postcue segment. Differential resistance to extinction was not found. The results did not support all of Longstreth's assumed functions. The motivational effects were interpreted using Spence's and Amsel's instrumental learning paradigms.
Date: May 1974
Creator: Morey, John Christopher
Partner: UNT Libraries

The Effects of Increased Equipment Speed on Online Database Searching Practices

Description: This study reports changes in online database searching at North Texas State University when equipment speed was increased. Data were from database vendor invoices and price and sale data of online equipment. The hypotheses examined the relationship between the decrease in the cost of online equipment and the change to faster online equipment and the change in the number of databases that changed for online types. The change in equipment was related to changes in the number of offline prints per hour, the average time per search, the average number of descriptors per search, the number of searches per month, and the rank order of database use over the studied period. The increase in the number of databases with billed types was related to the number of online billed types produced. The number of prints was related to the number of billed types. Time spent online was examined for annual seasonal cycles. The major statistical tool was time-series analysis, although other methods were applied.
Date: May 1987
Creator: Masters, Gary E. (Gary Everett)
Partner: UNT Libraries

The Effects of Increasing Rates of Reinforcement Through an Alternative Fluent Behavior on the Acquisition and Extinction of Behavior in Dogs

Description: The purpose of the present study was to experimentally investigate the effects of interspersing the opportunity to perform a fluent behavior during the acquisition of a new behavior. The experimenter trained left and right paw movements in domestic canines using a multiple treatment design. One paw movement was trained with a typical shaping procedure while the other was trained with an opportunity to perform a fluent behavior, touching the dog’s nose to a plastic disc, following each successive approximation in the shaping procedure. Two extinction phases were implemented during the experiment. The results showed that higher rates of reinforcement were achieved primarily following changes in criteria for reinforcement for the behavior in acquisition. There were no effects on rate of acquisition of the behavior, but adding an alternative fluent behavior may have slowed the differentiation between the reinforced behavior and alternative behaviors for one dog. The behavior trained with the addition of an alternative fluent behavior extinguished more quickly than in the control condition and extinguished at similar rates to the opposite leg movement. This suggests that the technique of offering an alternative fluent behavior may facilitate the chaining of the opposite behavior with the behavior targeted for reinforcement.
Date: August 2012
Creator: Coulter, Laura E.
Partner: UNT Libraries

The Effects of Individualized Test Coaching on Teacher Certification Test Scores.

Description: While student populations are growing, the gatekeeping devices of teacher certification examinations prevent many who want and are trained to teach from entering the profession. If failing these exams predicted failure to teach well, blocking students who do not pass certification exams from entering the profession might be a well-reasoned policy. However, many studies indicate that there is little correlation between certification test scores and quality of teaching. The present study investigated the effectiveness of a program to improve the scores of Texas elementary preservice teachers on a required certification exam. The program consisted of one-on-one coaching of preservice teachers upon the completion of coursework and prior to their taking the state's certification exam. Subjects' scores on a representative form of the certification test were used as pre-treatment measures. The content of the treatment program was individualized for each subject and determined by the specific items missed by each subject on the representative form. The post-treatment measure was the subject's score on the certification exam. Scores on the representative form and on the certification examination were compared to determine if there were significant differences between scores of preservice teachers who had been coached and those who were not coached. Since subjects voluntarily enrolled in the treatment, initial differences between coached and uncoached groups were controlled through analysis of covariance and pairwise matching. Descriptive statistics, t-tests for dependent samples, repeated measures analysis of variance, and univariate analyses of variance and covariance all indicated that there were statistically significant differences between the scores on the certification test of coached and uncoached students. Coached students showed greater improvement in scores than uncoached, with Hispanic subjects showing greater improvement than Caucasian subjects. Analyses that examined the differences between the coached and uncoached subjects on the domain and competency scores that make up the raw ...
Date: August 2008
Creator: Hall, Kathryn Cowart
Partner: UNT Libraries

The Effects of Induced Anxiety and Levels of IPAT Anxiety on a Gestalt Closure Task

Description: It was proposed that a study be done to investigate the problem of relating anxiety to the phenomenon of Gestalt closure. This study problem sought to demonstrate a systematic relationship between Gestalt closure, in terms of accuracy and speed, and possible interaction between levels of anxiety and induction of anxiety.
Date: January 1969
Creator: Sterling, F. R.
Partner: UNT Libraries

The Effects of Instruction on the Singing Ability of Children Ages 5-11: a Meta-analysis

Description: The purpose of the meta-analysis was to address the varied and somewhat stratified study results within the area of singing ability and instruction by statistically summarizing the data of related studies. An analysis yielded a small overall mean effect size for instruction across 34 studies, 433 unique effects, and 5,497 participants ranging in age from 5- to 11-years old (g = 0.43). The largest overall study effect size across categorical variables included the effects of same and different discrimination techniques on mean score gains. The largest overall effect size across categorical moderator variables included research design: Pretest-posttest 1 group design. Overall mean effects by primary moderator variable ranged from trivial to moderate. Feedback yielded the largest effect regarding teaching condition, 8-year-old children yielded the largest effect regarding age, girls yielded the largest effect regarding gender, the Boardman assessment measure yielded the largest effect regarding measurement instrument, and song accuracy yielded the largest effect regarding measured task. Conclusions address implications for teaching, research pedagogy, and research practice within the field of music education.
Date: August 2015
Creator: Svec, Christina L.
Partner: UNT Libraries

Effects of Instructional Methods on Student Performance in Postsecondary Developmental Mathematics

Description: This study examined success rates and end-of-semester grades for three instructional methods used in developmental algebra and college algebra. The methods investigated were traditional lecture, laboratory, and computer mediated learning. The population included the 10,095 students who had enrolled in developmental algebra and college algebra at Richland College in Dallas, Texas, for five semesters. Success was defined as earning a grade of A, B, C, or D in a course.
Date: May 1999
Creator: Hernandez, Celeste Peyton
Partner: UNT Libraries

The Effects of Interactions with IRS Employees on Tax Practitioners' Attitudes toward the IRS

Description: The purpose of this study was to determine the effects of interactions with IRS employees on tax practitioners' attitudes toward the IRS. The mission of the IRS is to inspire the highest degree of public confidence as it collects the proper amount of tax revenues at the least cost to the public. The IRS believes it must project a favorable image to tax practitioners in order to foster a high level of support for its mission. Prior surveys of tax practitioners found that practitioners have generally unfavorable attitudes toward the IRS and its employees. This study examined whether the unfavorable attitudes result from interactions with IRS employees, and provides empirical evidence of the effects of interactions with IRS employees on tax practitioners' attitudes toward the IRS.
Date: December 1992
Creator: Gutierrez, Theresa Kay
Partner: UNT Libraries

The Effects of Interactive Reviews and Learning Style on Student Learning Outcomes at a Texas State University

Description: This study investigated the effects of interactive lessons and learning style on student learning outcomes in self-defense education classes. The study utilized an experimental design that incorporated four self-defense education classes at the University of North Texas (UNT) during the fall semester 2007 (N = 87). A pre-test was administered during the first week of class to determine prior knowledge of the participants. The Visual Auditory Reading/Kinesthetic Inventory (VARK) was used to assess the learning styles of the students and was completed after the pre-test of knowledge was administered. The treatment group received the interactive lesson and the control received a paper review. The difference between the pre and posttest was used as a measure of improvement of the student's learning outcomes. A 2 (treatment/control) by 2 (pretest/posttest) ANOVA with repeated measures was conducted to examine the differential improvement in knowledge across the intervention. Based on the 2-way ANOVA there was a significant difference between the treatment group and the control group based on their learning outcomes. A repeated measures ANOVA was conducted to determine if there was a significant difference between the groups based on the pre and post test scores. Based on the results of a one week study it was determined that interactive lessons do make a significant impact on learning outcomes compared to traditional reviews.
Date: May 2008
Creator: Adams, Wesley
Partner: UNT Libraries

The Effects of Intergroup Competition and Noncompetition on the Decision Quality of Culturally Diverse and Culturally Non-Diverse Groups

Description: The primary purpose of this study was to explore the challenges and benefits associated with cultural diversity within groups. The research hypotheses were proposed to test the effects of cultural diversity on group performance and group processes by comparing culturally diverse and culturally homogeneous groups under conditions of intergroup competition and noncompetition. This experiment was conducted using 500 upper-level undergraduates enrolled in the principles of management course for the fall semester.
Date: August 1995
Creator: Faden, Sandra K. (Sandra Kay)
Partner: UNT Libraries

The Effects of Interpersonal Attraction on a Classroom Speaking Situation

Description: It was the purpose of this study to investigate the dynamics that exist in a classroom speaking situation. In particular, the study sought to explore the relationship of the speaker to his audience and how the quality of this relationship would affect the ability of the speaker to communicate.
Date: August 1966
Creator: Guernsey, Dennis B.
Partner: UNT Libraries

The Effects of Interresponse Intervals on Behavioral Variability in Humans

Description: The present experiment studied the relationship between interresponse intervals and behavioral variability. Subjects emitted sequences of 4 keypresses on two keys on a variability schedule that delivered points when the current 4-response sequence differed from the previous 5 sequences. Three experimental conditions were studied; no interresponse interval, 4-s interresponse interval and 8-s interresponse interval. Interresponse intervals followed each of the first three responses in each sequence. Two groups were used to study initial training histories. Group 1 was first exposed to the no-interresponse interval condition. Group 2 was first exposed to the 4-s interresponse interval condition. Subjects were then exposed to the different interresponse interval conditions. There was little change in variability across conditions. However, the variability observed in the subjects first exposed to the 4-s interresponse interval was greater than the variability observed in subjects first exposed to no-interresponse interval. There was higher-order response patterning in both groups, but it was more pronounced in the no-interresponse interval group.
Date: December 1993
Creator: Reilly, Mark P. (Mark Peter)
Partner: UNT Libraries

The Effects of Interspersed Trials and Density of Reinforcement on Accuracy, Looking Away, and Self-Injurious Behavior of a Child with Autism

Description: This research examines the effects of task interspersal and density of reinforcement on several behaviors of an autistic 6-year-old boy during the performance of a visual matching task and two auditory matching tasks. Experiment 1 investigated the effects of interspersing high and low accuracy tasks on correct matching responses, positions of matching responses, looking away, and self-injurious behavior (SIB). The effects of interspersed trials were evaluated using an ABAB multiple treatments design. Results indicated that interspersed trials produced slightly more correct responses during the visual matching task; however, correct responses decreased during the other two tasks. The use of interspersed trials also decreased looking away from the stimuli and SIB. Experiment 2 evaluated the effects of reinforcement density apart from task interspersal. Two conditions, reinforce-corrects-only and reinforce-all-responses, were compared in Experiment 2. Correct responses increased slightly for all three tasks during the reinforce-all-responses condition. Looking away and SIB were very infrequent throughout Experiment 2.
Date: May 2000
Creator: Ybarra, Rita
Partner: UNT Libraries

Effects of interviewer's impersonal and personal self-disclosures on somatic symptom verbalizations of psychiatric outpatients

Description: A literature review indicated that psychopathological symptomology must be considered within the social context of the patient. Recent research has suggested that the psychopathological symptoms of the psychotic patient function on a covert level of communication as a strategy to control the threat of interpersonal intimacy. The present investigation similarly examined the interpersonal function of another class of patient symptomology, somatic symptoms.
Date: August 1981
Creator: Skenderian, Daniel
Partner: UNT Libraries