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The Implications of Social Media: Secondary Teachers' use of Social Media for Personal, Professional, and Instructional Purposes (open access)

The Implications of Social Media: Secondary Teachers' use of Social Media for Personal, Professional, and Instructional Purposes

Social media has the potential to be a critical force in creating connected educators. The collaborative nature of social media encourages personal connection, professional enrichment, and learning through co-creation of meaning. Secondary teachers are in a place that would permit them to harness these affordances, not only in their personal and professional environments, but also in their classrooms. This qualitative phenomenographic study aimed to uncover how secondary teachers used social media for personal, professional, and instructional purposes. Further, this study sought to understand secondary teachers' attitudes and beliefs toward social media. Their current state of social media use was also of interest, as were the types of relations secondary teachers had with social media. To better understand the stories and experiences realized by these educators, ten secondary teachers were engaged using a semi-structured interview process. These teachers presented with varying backgrounds, education, and teaching focus. The interviews provided a textual representation of their social media stories. Interview transcripts were transposed into thick rich accounts describing their experiences, thoughts, ideas, and how they understood social media in their personal, professional, and instructional lives. It was found that the current state of social media use by secondary teachers was primarily limited to …
Date: August 2016
Creator: Quintanilla, Brenda U.
System: The UNT Digital Library
Observed Parenting Aspects of Child Compliance in Custodial Grandfamilies (open access)

Observed Parenting Aspects of Child Compliance in Custodial Grandfamilies

Custodial grandmothers and grandchild (aged 4 to 12) dyads (N = 170) completed self-report, other-report, and an observational task that captured child HI, expressive social support, and custodial grandmother-grandchild compliance variables. A multivariate analysis of covariance tested differences between high and low hyperactivity-inattention on observed parenting variables while controlling for child age. While overall results were not significant, there were significant differences between child age and observed parenting variables. A hierarchical regression model revealed that, when controlling for age, child hyperactivity-inattention does not moderate the relationship between commands given by a custodial grandmother and child compliance, but revealed that direct commands from the grandmother predicted compliance. A second hierarchical regression model suggested that encouragement and praise (versus criticism and discouragement) from a grandmother moderated the relationship between grandmother commands and child compliance, when controlling for child age. It appeared that when grandmothers gave indirect commands more frequently, encouragement and praise instead of criticism was associated with greater compliance. In dyads with frequent direct commands given, compliance was high, however dyads who scored high in direct commands with criticism and discouragement were most likely to comply. This study adds to the literature by providing insight into the challenges and strengths for …
Date: August 2016
Creator: Portner, Laura Collier
System: The UNT Digital Library
Environmental Ethics from the Periphery: José Lutzenberger and the Philosophical Analysis of an Unecological Economics (open access)

Environmental Ethics from the Periphery: José Lutzenberger and the Philosophical Analysis of an Unecological Economics

This dissertation provides a philosophical analysis about the influence colonialism had over capitalism's current configuration and how their intricate interplay impacts both the social and the ecological spheres, in both central and peripheral countries. Such analysis draws from the work of José Lutzenberger, a Brazilian environmentalist. The current capitalist economic system tends to disregard the environment, since it would be greatly affected by negative externalities. A negative externality is an economic activity that imposes a negative effect on an unrelated third party. Many negative externalities are related to the environmental consequences of production and consumption. In addition, this dissertation explores the fact that an ecological crisis is also a social crisis. A genealogical and existential thread going from Brazil's early days as one of Portugal's colonies to the present is drawn, showing how colonialism helped to create the foundations and the conditions for the current exploitative capitalist system, in Brazil and elsewhere. To change this situation, the environment should not be entrusted to private interests but to an institution responsible for the good of society as a whole. Genuinely green economies are more prone to appear on the periphery, but only if global economic justice is achieved first.
Date: August 2016
Creator: Valenti Possamai, Fabio
System: The UNT Digital Library
2D and 3D Fabrication Devices: Can They Improve Spatial Reasoning Skills in Children? (open access)

2D and 3D Fabrication Devices: Can They Improve Spatial Reasoning Skills in Children?

The purpose of this study is to evaluate the potential benefit of two hours of activities involving 2D and 3D fabricators on the spatial reasoning skills of children in Grades 4 and 5, ages 9 to 10, from a private school in Southeast Texas. Can the introduction to hands-on activities with products created with these devices and learning about how these devices operate improve spatial reasoning skills? The research also evaluates the use of the Shapes Test as a valid measure of the spatial reasoning skills of children. The Cube Design and Spatial Memory subtests of the UNIT (Universal Nonverbal Intelligence Tests) were used for evaluating the spatial reasoning skills of the participants, based on their respected validity, along with a Shapes Test that is in development. Discussion regarding gender, language, and experiential theories of spatial reasoning skill development are included in the literature review.
Date: August 2016
Creator: Zimmerman, Ellen L
System: The UNT Digital Library
Run, Women, Run! Female Candidates and Term Limits: A State-Level Analysis (open access)

Run, Women, Run! Female Candidates and Term Limits: A State-Level Analysis

This dissertation seeks to explain the puzzle in the state politics literature which expects females to benefit from the enactment of term limits, but initial research finds the number of female in office decreases after the implementation of term limits. Examining this puzzle involves three separate stand-alone chapters which explore female candidate emergence (1), success rates (2), and women-friendly state legislative districts (3). The goal of the dissertation is to reconcile the puzzle while adding insight into how female candidates behave at the state-level. Overall, I find that term limits increases female descriptive representation by increasing the likelihood a female candidate will run and win an election.
Date: August 2016
Creator: Pettey, Samantha
System: The UNT Digital Library
A Comparison of Treatments for Posttraumatic Stress Disorder Symptoms: Memory Specificity Training (MeST) and Cognitive Processing Therapy (CPT) (open access)

A Comparison of Treatments for Posttraumatic Stress Disorder Symptoms: Memory Specificity Training (MeST) and Cognitive Processing Therapy (CPT)

The effectiveness of memory specificity training (MeST) was compared with standard cognitive processing therapy (CPT) in treatment of individuals with posttraumatic stress disorder. Eighteen adults aged 18-36 were randomly assigned to the MeST intervention (n = 9) or to the active control group (n = 9) of CPT. Both treatments were administered in group format across 6 weeks. MeST consisted of 6 weekly sessions, while CPT consisted of 12 biweekly sessions. The trial was undertaken in the Psychology Clinic of the University of North Texas, with randomization to conditions accomplished via computer random number generator. The primary outcome measure was change in PTSD symptoms post-treatment from baseline. Sixteen individuals (13 women and 3 men; MeST n = 8 and CPT n = 8) completed treatment and their data was analyzed. MeST significantly decreased PTSD symptomology at post-treatment and these results were maintained at 3 months post-treatment. MeST was found to be as effective as the established CPT intervention at reducing PTSD symptomology. Both MeST and CPT significantly increased participants' ability to specify memories upon retrieval at post-treatment, with results maintained at follow-up. There were no significant effects of MeST or CPT in ability to increase overall controlled cognitive processing at …
Date: August 2016
Creator: Maxwell, Kendal Lynn
System: The UNT Digital Library
Group Activity Play Therapy for Preadolescents: Effects on Low Self-Esteem (open access)

Group Activity Play Therapy for Preadolescents: Effects on Low Self-Esteem

Research shows that preadolescent females are more prone to negative self-perceptions than their male counterparts which places them at greater risk of developing mental health problems stemming from low self-image. The purpose of this randomized, controlled outcome study was to examine the effectiveness of group activity play therapy (GAPT) compared to an evidenced based social skills/self-esteem group. Participants were 29 fourth and fifth grade girls in two Title I schools in the southwest U.S. referred by teachers and school counselors as presenting with low self-esteem. Participants identified as 45% Latina, 38% Caucasian, 14% African American, and 3% Asian. Children were randomly assigned to either 16 sessions of GAPT (experimental group; n = 15) or 13 sessions of an evidenced based social skills/self-esteem group intervention (control group; n = 14). Results from a 2 (Group) by 3 (Times) repeated measures ANOVA indicated that, compared to the control group over time, the GAPT group reported statistically significant improvement in self-esteem with a moderate to large treatment effect. Teachers did not report a statistically significant difference between the two groups over time. However, teachers reported noteworthy improvement for children in both treatment groups, with generally stronger improvement for the GAPT group. Overall, results …
Date: August 2016
Creator: Yousef, Dina K.
System: The UNT Digital Library
Elementary Students' Critical Examination of Characters in Children's Literature Depicting Social Justice (open access)

Elementary Students' Critical Examination of Characters in Children's Literature Depicting Social Justice

Despite the ruling of Brown vs. The Board of Education of Topeka, segregation in schools is still quite visible with suburban schools educating a student body of more than 70% White and urban schools comprised of mostly Black, Hispanic, and Asian students. Ideally, a school should dispel social and structural inequities through curriculum and quality resources, but fallibly, schools continue to be the vehicles to maintaining the status quo. Students who develop critical awareness and cultivate a critical literacy stance can become agents of change toward a more democratic society. In the current study, urban upper-elementary-age students were asked to engage in a critical literacy event by critically examining the power positions of characters in books that depict historical social injustice. The six female participants met in several sessions to read books and a newspaper article, use a critical reader response tool, and then engage in critical conversations about the books' characters. Their dialogue was recorded and analyzed using a critical discourse qualitative methodology. The findings show that older elementary students are capable of seeing multiple perspectives of an issue and can explain characters' power from born from privilege and fueled by fear and how a shift in power may …
Date: August 2016
Creator: Paiva, Deanne
System: The UNT Digital Library
Understanding the Information Seeking of Pre-Kindergarten Students: An Ethnographic Exploration of Their Seeking Behaviors in a Preschool Setting (open access)

Understanding the Information Seeking of Pre-Kindergarten Students: An Ethnographic Exploration of Their Seeking Behaviors in a Preschool Setting

Although there has been research conducted in the area of information seeking behavior in children, the research focusing on young children, more specifically on pre-kindergarten students, is almost nonexistent. Children at this age are in the preoperational developmental stage. They tend to display curiosity about the world around them, and use other people as a means to gain the information they are seeking. Due to the insistence from President Obama to implement pre-kindergarten programs for all low and middle class children, the need to understand the cognitive, emotional, and physical needs of these children is becoming increasingly imperative. To researchers, the actions displayed by these young children on a daily basis remain vital in determining the methods by which they are categorized, studies, and even taught. This study employed Deci and Ryan's self-determination theory (SDT), Dervin's sense-making theory, Kuhlthau''s information search process model (ISP), and Shenton and Dixon's microcosmic model of information seeking via people to lay the theoretical foundational framework. This ethnographic study aimed to fill the age gap found in information seeking literature. By observing young children in the school setting, I gained insight into how these children seek information. The resulting information collected via field observations and …
Date: August 2016
Creator: Stewart, Sarah Nykole
System: The UNT Digital Library
Learner Modal Preference and Content Delivery Method Predicting Learner Performance and Satisfaction (open access)

Learner Modal Preference and Content Delivery Method Predicting Learner Performance and Satisfaction

The purpose of the study was to investigate how the online, computer-based learner's personal learning profile (Preference), the content delivery method supplemented with visual content based on Neil Fleming's VARK (visual, aural, read/write, kinesthetic) model (Content), and the interaction of Preference and Content, influenced learner performance (Performance) and/or learner self-reported satisfaction (Satisfaction). Participants were drawn from a population of undergraduates enrolled in a large public southwestern research university during the fall 2015 semester. The 165 student participants (13.79% completion rate) were comprised of 52 (31.5%) females and 113 (68.5%) males age 18-58+ years with 126 (76.4%) age 18-24 years. For race/ethnicity, participants self-identified as 1 (0.66%) American Indian/Alaska Native, 21 (12.7%) Asian/Pacific Islander, 27 (16.4%) Black, non-Hispanic, 28 (17%) Hispanic, 78 (47.3%) White, non-Hispanic, 10 (6.1%) other. Reported socioeconomic status was 22 (13.3%) withheld, 53 (32.1%) did not know, 45 (27.3%) low, 13 (7.9%) moderately low, 16 (9.7%) middle, 8 (4.8%) upper middle, and 8 (4.8%) upper. This causal-comparative and quasi-experimental, mixed-method, longitudinal study used researcher-developed web-based modules to measure Performance and Satisfaction, and used the criterion p < .05 for statistical significance. A two-way, 4 x 3 repeated measures (Time) analysis of variance (RM-ANOVA) using Preference and Content was …
Date: August 2016
Creator: Copeland, Matthew Blair
System: The UNT Digital Library
Persistence Patterns of Mathematics and Science Majors: A Profile of Highly Motivated Freshmen (open access)

Persistence Patterns of Mathematics and Science Majors: A Profile of Highly Motivated Freshmen

Despite an increasing demand for college graduates skilled in science, technology, engineering, and mathematics ("STEM") fields, a substantial number of students who choose these majors leave after taking their first-year "gateway" math and science coursework. Research has shown GPA to be a salient predictor of persistence in STEM majors: Students who earn high grades in gateway courses are more likely to continue, and those who earn low grades are more likely to leave. However, a small number of students defy that expectation: Despite a low gateway course GPA, they persist not just to the sophomore year but all the way to graduation. The purpose of this study was to determine what other experiences, motivations, or attributes aside from academic performance influence these students to persist. A qualitative approach was taken with the use of semi-structured interviews, which provided a means for analysis based on insights directly from students. An invitation was sent to a cohort of graduating math and science majors at a large public institution, and 10 eligible volunteers were chosen to participate. A thematic analysis was conducted to seek common themes in the students' interviews regarding their experiences in their gateway coursework, their feelings towards their chosen major, …
Date: August 2016
Creator: Gonzales, Erin E.
System: The UNT Digital Library
The Impact of Digital Games on High School Students' Academic Achievement in Mathematics Education: A Meta-Analytic Investigation (open access)

The Impact of Digital Games on High School Students' Academic Achievement in Mathematics Education: A Meta-Analytic Investigation

The focus of this study was to conduct a meta-analytic investigation to combine the results obtained in independent studies aimed at determining the effectiveness of using digital games, as opposed to traditional methods, as a strategy for improving students' performance in high school mathematics. The major question of this study is: "Does the research on the use of games in high school mathematics support the use of games as a teaching strategy for improving student achievement?" To answer this question, meta-analysis was employed. Meta-analysis synthesizes and analyzes the quantitative data collected in independent and multiple empirical studies carried out on similar topics, situations, and hypotheses in order to reach a general judgment regarding the results of these studies. To determine which studies to use, specific criteria including articles published in refereed journals, thesis, and dissertation studies with experimental and control groups, research with effect size, sample size, standard deviation, and means. Based on these criteria, it was decided to include six experimental studies in the meta-analysis. The result showed that there was no significant differences between the use of digital games and traditional methods to teach mathematics in high school. The weighting factor of the two variables, standard deviation and …
Date: August 2016
Creator: Okeke, Godwin Nnaemeka
System: The UNT Digital Library
The Relationship Between Shame and Attachment Styles (open access)

The Relationship Between Shame and Attachment Styles

Despite research documenting the association between shame and aspects of poor psychological functioning, shame's adverse effects have remained largely invisible in modern societies. Shame has been described as the "attachment emotion" (Lewis, 1980), yet, there is little research that examines the relationship between attachment style and shame, and conclusions from this research are tempered by methodological limitations. The current study aimed to address methodological limitations with a quasi-experimental design and employed measures of state and trait shame, shame coping styles, an Emotional Stroop task for assessing implicit shame, and a shame mood induction procedure (MIP). This methodology provided a basis to examine differences by attachment style for 271 university students in state, trait, and implicit shame, as well as the use of maladaptive shame coping styles at baseline and following a shame MIP. Additionally, a qualitative analysis of the shame MIP written responses was conducted to provide a more nuanced understanding of the task used to elicit feelings of shame and individual differences in events identified as shame-triggering. Results revealed that students evidencing an insecure attachment style (i.e., preoccupied, fearful, or dismissive). reported significantly more state and trait shame compared to students evidencing a secure attachment style after the shame …
Date: August 2016
Creator: Atkins, Sarah Ann
System: The UNT Digital Library
Understanding Principal Perceptions of Stress and Burnout: A Qualitative Case Study in North Texas School Districts (open access)

Understanding Principal Perceptions of Stress and Burnout: A Qualitative Case Study in North Texas School Districts

This qualitative case study examined principals' perceptions regarding stress and burnout, investigated perspectives regarding ways to alleviate chronic stress, and analyzed the extent to which future role expectations are related to chronic stress and feelings of burnout. Perceptions of eight elementary principals in large, suburban school districts who experienced similar professional preparation prior to receiving their first principalship were analyzed. Participants, identified through criterion sampling, completed a demographic survey and then participated in a one-on-one interview with the researcher. Once data were collected, interviews were transcribed and analyzed to determine categories and themes. Findings revealed that participants struggle with significant stress in six specified domains: school type, students, parents and community, staff, district personnel, and other. Half of participants perceive that their stress will rise during the next five to ten years. Thirty-eight percent predicted that job stress will decline in the coming years, though they do not believe that identified stress factors will decrease. Instead, they believe that factors such as experience will help them to deal more effectively with the same challenges. Furthermore, 63% of participants do not plan to remain in their current principalship until retirement. All participants reported current personal stress-management strategies that fall into the …
Date: August 2016
Creator: Lovell, Joy E.
System: The UNT Digital Library
Self-Control in Overweight and Obese Individuals: The Relationship of Dispositional Self-Control and Blood Glucose (open access)

Self-Control in Overweight and Obese Individuals: The Relationship of Dispositional Self-Control and Blood Glucose

Currently, the etiology of obesity is conceptualized as a confluence of environmental, socioeconomic, behavioral, biological and genetic factors. With regard to behavioral factors, some have suggested that a failure of self-control may contribute to the difficulty of an overweight/obese individual because of their inability to resist food or maintain physical activity. Recent research proposed that self-control could be described as similar to a muscle that can be fatigued. Thus, if an individual engages in a self-control task they have lessened ability to utilize self-control on a subsequent task. Theory also suggests self-control may be fueled by a finite resource, identified as blood glucose. The role blood glucose plays is important to understand, especially in overweight and obese populations, as they may be more likely to be insulin resistant. In effect overweight and obese individuals are less likely to adequately process glucose. Therefore overweight/obese individuals might react to self-control tasks differently than normal weight individuals. Participants who were considered normal weight, overweight, and obese were recruited from the UNT research pool. They answered questions about their trait self-control in daily life and engaged in either a task that required them to exert self-control (e.g., resist crossing out a letter unless criteria …
Date: August 2016
Creator: Edwards, Kate
System: The UNT Digital Library
Maturation of Endothermic Capacity within the Avian Developmental Spectrum: A Characterization of Thermoregulatory Metamorphosis (open access)

Maturation of Endothermic Capacity within the Avian Developmental Spectrum: A Characterization of Thermoregulatory Metamorphosis

An avian embryo is ectothermic, with body temperature determined by environmental temperature. Upon hatching, the neonate begins a conversion so that endothermic capacity becomes feasible and body temperature becomes independent of environment. Whole animal metabolic rate and ventilation response, cardiovascular development, and maturation of muscle mitochondrial flux were the focus of this dissertation because of the direct role in shivering thermogenesis. Precocial ducks and altricial Double-crested Cormorants exhibit increasing hematocrit and disproportionate increases in fractional heart mass resulting in greater oxygen delivery capacity and increased capacity of muscles to utilize oxygen compared with ectothermic American Alligator and Common Snapping turtles. By selecting for faster growth and higher meat yield in the domestic chicken, differences in whole-animal, tissue, cellular, and regulatory responses are evident between broiler and layer type birds. In the altricial red-winged blackbird, despite appearance of a whole animal endothermic response sometime after 7 dph, capacity of skeletal muscles involved in shivering thermogenesis peaks prior to that time. Thus, full development of endothermy is delayed in this species, allowing the altricial nestling to allocate energy towards growth rather than metabolic maintenance. Hypothyroidism in neonate red-winged blackbirds results in delayed maturation of the cardiovascular system and mitochondrial oxidative capacity of …
Date: August 2016
Creator: Sirsat, Sarah Goy
System: The UNT Digital Library
Faculty Experiences with Collaborative Learning in the Online Classroom (open access)

Faculty Experiences with Collaborative Learning in the Online Classroom

The purpose of this qualitative case study was to identify the perceptions and experiences that instructors in higher education have toward providing collaborative learning activities and opportunities in their online classroom. Through semi-structured interviews, the experiences of four higher education instructors from two universities were collected concerning their provision of collaborative learning opportunities in their online classrooms. A multi-phase coding process was used to analyze the information, including the constant comparative coding method for theme and category development. Three themes emerged from the study: online communication approaches matter, there are challenges and supports for online collaborative learning, and care is at the core of online learner support. The findings are discussed and recommendations are provided for the development and design of meaningful online collaborative learning.
Date: August 2016
Creator: Robinson, Heather A.
System: The UNT Digital Library
Creating Musical Momentum: Textural and Timbral Sculpting with Intuitive Compositional Systems and Formal Design (open access)

Creating Musical Momentum: Textural and Timbral Sculpting with Intuitive Compositional Systems and Formal Design

This dissertation explores the analysis and creation of compositions from the standpoint of texture and momentum. It is comprised of four chapters. The first presents a number of concepts as tools for analysis, including textural typography and transformation, perception of time and psychological engagement of an audience, and respiration as a metaphor for musical momentum. The second and third chapters apply these tools to Gerard Grisey's "Periodes" and "Partiels," and Brian Ferneyhough's "Lemma-Icon-Epigram." The fourth explores specific methodologies used in composing my dissertation piece, "Phase," including the application of number systems ranging from formal to local levels.
Date: August 2016
Creator: Robin, Brad
System: The UNT Digital Library
Quantum Chemistry Calculations of Energetic and Spectroscopic Properties of p- and f-Block Molecules (open access)

Quantum Chemistry Calculations of Energetic and Spectroscopic Properties of p- and f-Block Molecules

Quantum chemical methods have been used to model a variety of p- and f-block chemical species to gain insight about their energetic and spectroscopic properties. As well, the studies have provided understanding about the utility of the quantum mechanical approaches employed for the third-row and lanthanide species. The multireference ab initio correlation consistent Composite Approach (MR-ccCA) was utilized to predict dissociation energies for main group third-row molecular species, achieving energies within 1 kcal mol-1 on average from those of experiment and providing the first demonstration of the utility of MR-ccCA for third-row species. Multireference perturbation theory was utilized to calculate the electronic states and dissociation energies of NdF2+, providing a good model of the Nd-F bond in NdF3 from an electronic standpoint. In further work, the states and energies of NdF+ were determined using an equation of motion coupled cluster approach and the similarities for both NdF2+ and NdF were noted. Finally, time-dependent density functional theory and the static exchange approximation for Hartree-Fock in conjunction with a fully relativistic framework were used to calculate the L3 ionization energies and electronic excitation spectra as a means of characterizing uranyl (UO22+) and the isoelectronic compounds NUO+ and UN2.
Date: August 2016
Creator: South, Christopher James
System: The UNT Digital Library
Stigma, Spirituality and Psychological Quality of Life in People Living with HIV: A Mixed Methods Approach (open access)

Stigma, Spirituality and Psychological Quality of Life in People Living with HIV: A Mixed Methods Approach

HIV is a potentially fatal virus that affects over 1,148,200 people in the United States. Due to the minority status that comes with living with HIV, PLH (people living with HIV) often encounter various aspects of stigma due to HIV, which contributes to suppressed overall psychological quality of life (PQOL).While the relationship between stigma and PQOL in PLH is well documented, little research examines mediators of this relationship. We hypothesized that spirituality (as measured by sense of peace, forgiveness of self and perceived fulfillment of life's goal) mediates the relationship between stigma and PQOL (as measured by depression, mental health and stress). We used an explanatory sequential mixed methods design which utilizes two distinct phases of the research process: quantitative (QUANT) analysis followed by qualitative (QUAL) analysis. Results of the QUANT phase suggest spirituality is a partial mediator in the relationship between stigma and PQOL in PLH. In the QUAL phase, we interviewed 15 PLH to elaborate on the relationships between the three constructs. We found PLH endorsed personalized stigma most frequently. Similarly, our results also indicate PLH experience stress, depression and anxiety as a result of their HIV status. Lastly, participant's interviewed most commonly described their spiritual beliefs as …
Date: August 2016
Creator: Purser, Megan
System: The UNT Digital Library
In Vitro Behavior of AZ31B Mg-Hydroxyapatite Metallic Matrix Composite Surface Fabricated via Friction Stir Processing (open access)

In Vitro Behavior of AZ31B Mg-Hydroxyapatite Metallic Matrix Composite Surface Fabricated via Friction Stir Processing

Magnesium and its alloys have been considered for load-bearing implant materials due to their similar mechanical properties to the natural bone, excellent biocompatibility, good bioactivity, and biodegradation. Nevertheless, the uncontrollable corrosion rate in biological environment restrains their application. Hydroxyapatite (HA, Ca10(PO4)6(OH)2) is a widely used bio-ceramic which has bone-like mineral structure for bone fixation. Poor fracture toughness of HA makes it not suitable for load-bearing application as a bulk. Thus, HA is introduced into metallic surface in various forms for improving biocompatibility. Recently friction stir processing (FSP) has emerged as a surface modification tool for surface/substrate grain refinement and homogenization of microstructure in biomaterial. In the pressent efforts, Mg-nHA composite surface on with 5-20 wt% HA on Mg substrate were fabricated by FSP for biodegradation and bioactivity study. The results of electrochemical measurement indicated that lower amount (~5% wt%) of Ca in Mg matrix can enhance surface localized corrosion resistance. The effects of microstructure,the presence of HA particle and Mg-Ca intermetallic phase precipitates on in vitro behavior of Mg alloy were investigated by TEM, SEM, EDX,XRD ,and XPS. The detailed observations will be discussed during presentation.
Date: August 2016
Creator: Ho, Yee Hsien
System: The UNT Digital Library
The Impact of Family Resilience Factors and Parent Gender on Stress Among Parents of Children with Autism (open access)

The Impact of Family Resilience Factors and Parent Gender on Stress Among Parents of Children with Autism

Parents of children with autism experience high degrees of stress. Research pertaining to the reduction of parental stress in families with a child with autism is needed. In this study, the relationship between family resilience, parent gender, and parental stress was examined. Seventy-one parents of young children with autism were surveyed. Regression and correlational analyses were performed. Results indicated that the vast majority of respondents reported significantly high levels of stress. Lower degrees of parental stress were correlated with higher degrees of family resilience. Family resiliency factors were significant contributors to the shared variance in parental stress. Mothers of children demonstrated higher levels of stress than fathers. Suggested explanations of these findings are presented and clinical and research implications are provided. The findings of this study provide evidence for the importance of facilitating family resilience for parents of children with autism and affirm differing stress levels between mothers and fathers.
Date: August 2016
Creator: Cheatham, Kelly L.
System: The UNT Digital Library
Quantum Drinfeld Hecke Algebras (open access)

Quantum Drinfeld Hecke Algebras

Quantum Drinfeld Hecke algebras extend both Lusztig's graded Hecke algebras and the symplectic reflection algebras of Etingof and Ginzburg to the quantum setting. A quantum (or skew) polynomial ring is generated by variables which commute only up to a set of quantum parameters. Certain finite groups may act by graded automorphisms on a quantum polynomial ring and quantum Drinfeld Hecke algebras deform the natural semi-direct product. We classify these algebras for the infinite family of complex reflection groups acting in arbitrary dimension. We also classify quantum Drinfeld Hecke algebras in arbitrary dimension for the infinite family of mystic reflection groups of Kirkman, Kuzmanovich, and Zhang, who showed they satisfy a Shephard-Todd-Chevalley theorem in the quantum setting. Using a classification of automorphisms of quantum polynomial rings in low dimension, we develop tools for studying quantum Drinfeld Hecke algebras in 3 dimensions. We describe the parameter space of such algebras using special properties of the quantum determinant in low dimension; although the quantum determinant is not a homomorphism in general, it is a homomorphism on the finite linear groups acting in dimension 3.
Date: August 2016
Creator: Uhl, Christine
System: The UNT Digital Library
Logic, Emotion and Closure: Motivations for Choices of Faith (open access)

Logic, Emotion and Closure: Motivations for Choices of Faith

Spirituality and religiosity can play key roles in individual lives through influencing health, social relationships, political views, as well as many other facets (Newberg, D'Aquili & Rause, 2001; Milevsky & Levitt, 2004; Hirsh, Walberg & Peterson, 2013). As important as religious and spiritual beliefs are to societies, cultures, and individuals, little is known about which psychological factors determine choices of faith. Although there are likely many determinants of religious, spiritual, atheist or agnostic beliefs, this study explored four possible factors: critical thinking skills, need for cognition, need for emotional comfort/security, and need for closure. Participants included an undergraduate sample and a community sample. It was hypothesized that religious and spiritual individuals will have lower critical thinking skills, lower needs for cognition, higher needs for emotional comfort/security and higher needs for closure than agnostic and atheist individuals. Hypotheses also included potential interactions between these variables in predicting each faith path. Religiosity was measured using the I/E Religious Orientation Scale - Revised (Gorsuch & McPherson, 1989) and Spirituality was measured utilizing the Brief Multidimensional Measure of Religiousness/Spirituality (BMMRS) (Fetzer Institute, 1999). These two faith paths were also self -reported by participants after definitions of each were provided. Atheist and Agnostic beliefs were …
Date: August 2016
Creator: Jenkins, Elizabeth
System: The UNT Digital Library