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The Effects of Organic Surface Amendments on Soil Nutrients and Initial Tree Establishment

Description: This study examined the effects of replicating woodland soil surface horizonation on the nutrient status of underlying soils and the initial establishment and growth of trees. A total of 283 container grown trees were planted in a bufferzone around a future landfill site. Control amendments consisted of an 8 cm layer (0.5 m3) of wood chips applied in a circular area of 4.6 m2 around the trees' planting pit. For the treatment, a 2.5 cm layer of composted biosolids (0.15 m3 or 80 Mg/ha) was applied in a circular area of 4.6 m2 around the trees' planting pit followed by an 8 cm layer (0.5 m3) of wood chips. The results indicate that the replication of woodland soil surface attributes using composted biosolids can significantly improve the nutrient status of underlying soil. Some significant effects were seen under control conditions, too. However, the effects on tree establishment and growth parameters were, for the most part, not statistically significant.
Date: May 1999
Creator: Thuesen, Kevin (Kevin Andrew)
Partner: UNT Libraries

The Effects of Parent Training on the Amount and Variety of Food Consumed By a Child with Autism.

Description: The current study assessed the effectiveness of a training package, delivered in the form of a manual, to teach a parent to increase the variety and amount of food consumed by her son. The participant was a 5-year-old boy with Pervasive Developmental Disorder and limited food consumption. A changing criterion design across two variables, variety of food and quantity of food, was used. Results were that the parent who used the manual, with limited assistance from the experimenter, did succeed in increasing food variety and quantity of target foods.
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Date: May 2004
Creator: VanKirk, Tessa Schreiber
Partner: UNT Libraries

The Effects of Parental Divorce and Conflict on Adolescent Separation-Individuation

Description: The influence of parental marital status and parental conflict on the separation-individuation process of college students was investigated in the present study. Past studies have suggested that parental divorce and parental conflict accelerate separation. However, no studies have measured more than one dimension of separation-individuation. In this study the process of separation-individuation was operationalized as involving three dimensions: psychological separation from parents (Psychological Separation Inventory); emotional attachments to parents and peers (Inventory of Parent and Peer Attachment); and the development of an identity (Extended Objective Measure of Ego Identity Status). The sample consisted of 120 male and 120 female undergraduates between the ages of 18 and 22, one-half with parents who were married and one-half with parents who had divorced in the last five years. Subjects completed self-report measures of parental conflict, psychological separation, attachment to parents and to peers, and identity status. Predictions that parental conflict would affect students in intact families differently than their peers with divorced parents were not supported. Instead, parental divorce and conflict were found to have different effects on the components of the separation-individuation process. Subjects reporting higher parental conflict levels described more independent functioning, more negative feelings toward parents, less attachment to parents and to peers, and greater exploration of identity-related issues in comparison to those reporting low levels of conflict. Subjects with parents who had recently divorced reported lower attachment to parents, and greater identity exploration and reluctance to commit to an identity than subjects from intact families. Males reported greater independence from and less attachment to parents, and had committed to an identity without exploration less often than females. Results suggest that parental divorce and conflict may influence adolescent development in different ways. Exploratory analyses suggested that measures of conflict style are more highly related to indices of separation-individuation than measures ...
Date: August 1993
Creator: Marsh, Greg (Gregory Gene)
Partner: UNT Libraries

The Effects of Parental Divorce and Family Conflict on Young Adults Females' Perceptions of Social Support and Adjustment

Description: The purpose of this study was to explore the effects of parental divorce and family conflict during adolescence on young adult females' social support and psychological adjustment. The three areas explored were perceptions of relationship satisfaction and closeness, sources and amount of social support and adjustment. One hundred and forty-one female undergraduates, 53% from families in which their parents are still married and 47% from families in which a parental divorce occurred during adolescence, completed the following measures: the Dyadic Adjustment Scale (Spanier, 1976), the Social Provisions Scale-Source Specific (Cutrona, 1989), the Inventory of Common Problems (Hoffman & Weiss, 1986), the Family Environment Scale (Moos & Moos, 1981), and the Sibling Relationship Questionnaire (Furman & Buhrmester, 1985).
Date: May 1998
Creator: Quinn, M. Theresa
Partner: UNT Libraries

The Effects of Parental Marital Status, Just World Beliefs, and Parental Conflict on Trust in Intimate Heterosexual Relationships

Description: The effects of divorce on trust in intimate heterosexual relationships were investigated using a sample of 478 college students (156 males, 322 females). Subjects were asked to respond to scenarios and questionnaires assessing parental marital status, just world beliefs, parental conflict, and trust. Attitudes toward divorce and common problems were also assessed.
Date: December 1993
Creator: Taylor, Bryce E. (Bryce Ernest)
Partner: UNT Libraries

The Effects of Parenting Stress and Academic Self-Concept on Reading Ability in a Clinic Referral Sample

Description: This study investigated the relationships among the variables of parenting stress, academic self-concept, and reading ability. The purpose of this study was to determine whether parenting stress and academic self-concept contributed to the child's reading ability. Two hypotheses were investigated in an effort to accomplish this purpose. The subjects used in this study were forty-nine children and their primary caretakers referred to The Child and Family Resource Center, The University of North Texas, Denton, Texas, during the academic years of 1994 through 1999. Subjects ranged in age from seven to eighteen years of age. Academically, the subjects ranged from first graders through eleventh graders. All subjects lived in and attended schools in Denton County or neighboring counties. Parental employment ranged from unskilled laborers to medical doctors. The participating families included biological, step, adoptive, single, and divorced families. Abidin's Parenting Stress Index was used to measure parental stress experienced by the primary caretaker. The Intellectual and School Status cluster of the Piers-Harris Children's Self-Concept Scale was used to measure the child's academic self-concept and the Woodcock Reading Mastery Test-Revised provided a measure of the child's reading ability. Test scores were obtained following a review of The Child and Family Resource Center's documented files. Multiple regression statistics revealed no significant relationship between neither parenting stress and the child's reading ability nor the child's academic self-concept and reading ability. Standardized beta coefficients and bivariate correlation results indicated a relationship between academic self-concept and reading ability. Additional research is recommended for future research that encompasses a larger and more diverse sample.
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Date: May 2001
Creator: Maldonado, Michele L.
Partner: UNT Libraries

The Effects of Participation in a Buddy System on the Self-Concept, Academic Achievement, Attrition Rate, and Congruence Level of Community College Developmental Studies Students

Description: This dissertation sought to determine the effects of a buddy system on a student's self-concept, academic achievement, attrition rate, and congruence levels. The buddy system treatment randomly paired two students for the purposes of sharing ideas, working on assignments, getting to know each other, and supporting one another. The study included three randomly selected sections of pre-college level, developmental writing classes from the Brookhaven College of the Dallas County Community College District. Three other classes served as the control group, and one instructor taught all six sections of the course. Three instruments were used as measures of change: the Tennessee Self-Concept Scale (TSCS), designed by William H. Fitts, measured self-concept levels; the Personality and Educational Environment Scale (PEES), created by Roger Boshier, measured congruence levels; and a written paragraph measured achievement levels in English. Attrition percentages were based on the number of students enrolled during the second week of class who were not present during the sixteenth week of class. To test for significance, an analysis of covariance procedure was used on the TSCS, PEES, and written paragraph results, and a test for the difference between proportions for independent groups was used on the attrition percentages. The class sections were nested under either the experimental or the control group to identify significant differences between class sections. On the TSCS, a significance of .96 among sections and .48 between groups indicated no significant change had occurred in self-concept levels. For the PEES, a significance of .30 among sections and .75 between groups indicated no change had occurred in congruence levels. Finally, on the paragraph assessment, a significance of .87 among sections and .31 between groups showed no change had occurred in achievement levels. However, the test for significance of the difference between attrition percentages revealed that the buddy system treatment was ...
Date: December 1985
Creator: Cinclair, Carol
Partner: UNT Libraries

Effects of Partner Violence and Psychological Abuse on Women's Mental Health Over Time.

Description: This study examined the distinct effects of partner violence and psychological abuse on women's mental health over time. Latent growth modeling was used to examine stability and change over time, evaluating the course and consequences of each form of abuse. The size of women's social support network was examined as a mediator. The sample consisted of 835 African American, Euro-American, and Mexican American low-income women. Participants who completed Waves 1, 2, 3, and 5 were included in the study (n = 585). In general, partner violence decreased over time for all groups, while psychological abuse decreased over time for only Euro-American women. Whereas initial and prolonged exposure to psychological abuse was related to and directly impacted women's mental health, partner violence was only related to initial levels of mental health. Surprisingly, social support was only related to initial violence and distress and had no impact on the rate of change over time. These results have important implications for researchers and health care professionals. First, differences in the pattern of results were found for each ethnic group, reaffirming the notion that counselors and researchers must be sensitive to multicultural concerns in both assessment and intervention. For example, psychological abuse had a greater impact on the mental health of African American and Mexican American women than it did for Euro-American women, suggesting a shift in focus depending on the ethnicity of the client may be warranted. Second, this longitudinal study highlights the importance of future research to considerer individual differences in treating and studying victimized women. Understanding factors that contribute to individual trajectories will help counselors gain insight into the problem and in devising plans to prevent or reduce the occurrence and negative health impact of partner abuse.
Date: August 2006
Creator: Temple, Jeff R.
Partner: UNT Libraries

The Effects of PECS Training on Symbolic Matching Skills in Learners with Autism

Description: This study evaluated whether picture exchange communication system (PECS) training would result in the development of conditional relations among corresponding pictures, objects (reinforcers) and spoken words used in PECS training with learners with developmental disabilities. Three participants with autism and mental retardation were trained to use PECS. Match-to-sample procedures were used to assess all possible conditional relations among stimuli before, during, and after PECS training. None of the three participants in this study acquired conditional discriminations involving the pictures, reinforcers, and spoken words used in their PECS training.
Date: May 2009
Creator: Cranmer, Elizabeth
Partner: UNT Libraries

The Effects of Perceived Locus of Control and Dispositional Optimism on Chronic Pain Treatment Outcomes.

Description: The financial cost for health care and lost productivity due to chronic pain has been estimated at over $70 billion per year. Researchers have attempted to discover the psychosocial and personality factors that discriminate between people who learn to cope well with chronic pain and those who have difficulty adjusting. The purpose of the present study was to examine the effects of perceived locus of control and dispositional optimism on chronic pain treatment outcomes. Subjects reported significantly lower post-treatment pain levels as compared with pre-treatment levels (M = 0.66, SD = 1.58), t(45) = 2.85, p = .007 (two-tailed), but decreased pain was not associated with scores on the internality dimension of the Pain Locus of Control Scale (PLOC) or on the Life Orientation Test-Revised (LOT-R) (a measure of dispositional optimism). Overall, participants' increased coping ability was associated with scores on the LOT-R, but not with scores on the internality dimension of the PLOC. Subjects with the lowest pre-treatment scores on the LOT-R demonstrated significantly greater increases in post-treatment coping ability than those with the highest scores (F(2,40) = 3.93, p < .03). Participants with the highest pre-treatment scores on both the PLOC internality dimension and the LOT-R demonstrated greater post-treatment coping ability (F(2,32) = 4.65, p < .02), but not less post-treatment pain than other subjects. Participants' post-treatment LOT-R scores were significantly higher than their pre-treatment scores (M = 2.09, SD = 3.96), t(46) = 3.61, p = .001 (two-tailed), but post-treatment PLOC internality scores were not significantly higher than pre-treatment scores. Implications of these results are discussed.
Date: December 2004
Creator: Worsham, Scott L.
Partner: UNT Libraries

Effects of Perceived Quality, Product Category Similarity, and Brand Breadth on Consumers' Perceptions of Brand Extensions: Tests of Categorization Theory and Cognitive Response Theory

Description: Various constructs are related to predicting consumers' perceptions of brand extensions. Among these, three constructs, perceptions of perceived quality (PQ) associated with the parent brand, product category similarity (PCS) of an extension to its parent brand, and brand breadth (BB) of the parent, are central to many brand extension studies. The purpose of this study is to clarify the roles of these three constructs and to pit predictions from an alternative theoretical perspective — cognitive response theory — against predictions based on categorization theory.
Date: August 1994
Creator: Lee, Dongdae
Partner: UNT Libraries

The Effects of Perceptual Motor Enrichment Upon a Six Year Old with Cerebellar Brain Damage

Description: This study involved the effects of a perceptual motor enrichment program upon the motor skills of a six year old boy with cerebellar brain damage, who, with a control group of ten normal six year olds, was given a pre-test of motor skills. He and a child from the control group participated in a perceptual-motor enrichment program. The motor skills of both subjects were tested halfway through the program. Following the program, the experimental child, the control child, and the control group were post-tested on their motor skills. The testings showed that the greatest gains in motor skills were obtained by the experimental child, followed by the control child. The control group displayed little increase in motor skill performance.
Date: August 1986
Creator: Shepardson, Nina F. (Nina Fredrica)
Partner: UNT Libraries

Effects of Performance Levels of Subject Matter Experts on Job Analysis Outcomes

Description: Much research has been undertaken to determine how Subject Matter Expert characteristics affect job analysis outcomes. The current study seeks to discover if performance levels are related to current incumbents ratings of their positions. A group of 114 corporate associates, from two administrative positions, served as Subject Matter Experts (SME) for this study. Separate job analyses for each position were conducted using the Job Analysis Task Checklist. The results for each job were analyzed to determine if SME performance levels affected job analysis outcomes. The results for both jobs showed that there were very few differences in job analysis results as a function of SME performance levels.
Date: December 1997
Creator: Boyd, Charlotte Friedersdorff
Partner: UNT Libraries

Effects of Peripheral Nerve Injury on the Cells of the Dorsal Root Ganglion: a Role for Primary Cilia

Description: Primary cilia are ubiquitous sensory organelles found on most cell types including cells of the dorsal root ganglia (DRG). The DRG are groups of peripheral neurons that relay sensory information from the periphery to the CNS. Other cell types in the DRG include a type of glial cell, the satellite glial cells (SGCs). The SGCs surround the DRG neurons and, with the neurons, form functional sensory units. Currently are no reports describing the numbers of DRG cells that have cilia. We found that 26% of the SGCs had primary cilia. The incidence of cilia on neurons varied with neuron size, a property that roughly correlates with physiological characteristics. We found that 29% of the small, 16% of the medium and 5% of the large neurons had primary cilia. Primary cilia have been shown to have a role in cell proliferation in a variety of cell types. In some of the cells the cilia mediate the proliferative effects of Sonic hedgehog (Shh). In the CNS, Shh signaling through primary cilia affects proliferation during development as well as following injury, but no studies have looked at this function in the PNS. The SGCs and neurons of the DRG undergo complex changes following peripheral nerve injury such as axotomy. One marked change seen after axotomy is SGC proliferation and at later stages, neuronal death. We found that following axotomy there is a significant increase in the percentage of SGCs with primary cilia. We also found a significant increase in the percentage of medium-sized neurons with primary cilia. In other experiments we tested the idea that Shh plays a role in SGC proliferation. When Shh signaling was blocked following axotomy we found decreased proliferation of SGCs. This is the first report of a change in the percentage of cells with cilia following injury in ...
Date: December 2012
Creator: Smith, Sarah K.
Partner: UNT Libraries

Effects of pH and Substrate on Growth of Escherichia Coli and Pseudomonas Aeruginosa in Mixed Continuous Culture

Description: The express purpose for doing this project was to develop methods for the continuous culture of E. coli and P. aeruginosa as a mixed population, and to apply these methods in studying the effects of pH and substrate upon the growth of these two organisms in mixed continuous culture.
Date: January 1964
Creator: Cooper, Billy Howard
Partner: UNT Libraries