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Acute Effects of the Antibiotic Streptomycin on Neural Network Activity and Pharmacological Responses

Description: The purpose of this study is to find out that if antibiotic streptomycin decreases neuronal network activity or affects the pharmacological responses. The experiments in this study were conducted via MEA (multi-electrode array) technology which records neuronal activity from devices that have multiple small electrodes, serve as neural interfaces connecting neurons to electronic circuitry. The result of this study shows that streptomycin lowered the spike production of neuronal network, and also, sensitization was seen when neuronal network pre-exposed to streptomycin.
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Date: December 2014
Creator: Zeng, Wei Rong
Partner: UNT Libraries

The Acute Hormonal Response to the Kettlebell Swing Exercise

Description: The purpose of this investigation was to examine the acute hormonal response to a bout of kettlebell swing exercise. Ten healthy men (19-30 y, 23.6 ± 3.5 y, 174.6 ± 5.7 cm, 78.7 ± 9.9 kg) who were engaged in resistance training at least twice per week but were inexperienced with kettlebell swings participated in this study. Participants were familiarized with the kettlebell swing exercise during an initial visit. During the subsequent experimental protocol visit, participants performed 12 rounds of 30 seconds of 16-kg kettlebell swings alternated with 30 seconds of rest. Heart rate (HR) and rating of perceived exertion (RPE) were measured at the end of every round of swings. Fasted blood samples were collected pre-exercise (PRE), immediately post (IP), 15 minutes post (P15), and 30 minutes post exercise (P30) and analyzed for total testosterone (T), growth hormone (GH), cortisol, and lactate concentrations. Participants completed a total of 227 ± 23 swings (average swings per round: 19 ± 2). HR and RPE increased significantly (P < 0.05) throughout the exercise protocol. Lactate concentrations were significantly increased at all post exercise time points compared to PRE. T was significantly increased at IP compared to PRE. GH was significantly increased at IP, P15, and P30 compared to PRE. Cortisol was significantly increased at IP and P15 compared to PRE. 12 rounds of 30 seconds of kettlebell swing exercise induced an acute increase in T, GH, and cortisol concentrations in resistance trained men. Additionally, this exercise protocol induced a large increase in HR and lactate concentration. Thus, the kettlebell swing exercise might provide an effective method for simultaneous endurance and resistance training.
Date: December 2013
Creator: Budnar Jr., Ronald Gene
Partner: UNT Libraries

The Adagio of Mahler's Ninth Symphony: A Schenkerian Analysis and Examination of the Farewell Story

Description: Mahler's Ninth Symphony, since its premier in 1912, has sparked much debate about its programmatic meaning. This thesis provides an in-depth analysis of the Adagio and an examination of the controversy of the farewell story. In the process of the analysis I have compared my findings to some of the important authors in Mahler's field such as Vera Micznik, Henry-Louis de La Grange, and Christopher Orlo Lewis. Some of the conclusions are that a closer investigation of the music is necessary and that the programmatic reading of the farewell story can be appropriate.
Date: May 2011
Creator: Patterson, Jason
Partner: UNT Libraries

Adapting on the Plains: the United States Army's Evolution of Mobile Warfare in Texas, 1848-1859

Description: The Army, despite having been vexed for a century on how to effectively fight the Plains Indians, ultimately defeated them only a decade after the Civil War. This thesis will bring to the forefront those individuals who adapted fighting techniques and ultimately achieved victories on the Texas frontier before the Civil War. The majority of these victories came as a result of mounted warfare under the direction of lower ranking officers in control of smaller forces. The tactic of fighting Indians from horseback was shown to be effective by the Rangers and later emulated by the Army.
Date: May 2013
Creator: Buchy, Mark B.
Partner: UNT Libraries

Adaptive Advantages of Carotenoid Pigments in Alpine and Subalpine Copepod Responses to Polycyclic Aromatic Hydrocarbon Induced Phototoxicity

Description: Alpine zooplankton are exposed to a variety of stressors in their natural environment including ultraviolet radiation. Physiological coping mechanisms such as the accumulation of photoprotective compounds provide these zooplankton protection from many of these stressors. Elevated levels of carotenoid compounds such as astaxanthin have been shown to help zooplankton survive longer when exposed to ultraviolet radiation presumably due to the strong antioxidant properties of carotenoid compounds. This antioxidant capacity is important because it may ameliorate natural and anthropogenic stressor-induced oxidative stress. While previous researchers have shown carotenoid compounds impart increased resistance to ultraviolet radiation in populations of zooplankton, little work has focused on the toxicological implications of PAH induced phototoxicity on zooplankton containing high levels of carotenoid compounds. This thesis discusses research studying the role that carotenoid compounds play in reducing PAH induced phototoxicity. By sampling different lakes at elevations ranging from 9,500' to 12,700' in the front range of the Colorado Rocky Mountains, copepod populations containing different levels of carotenoid compounds were obtained. These populations were then challenged with fluoranthene and ultraviolet radiation. Results discussed include differences in survival and levels of lipid peroxidation among populations exhibiting different levels of carotenoid compounds, and the toxicological and ecological implications of these results.
Date: May 2010
Creator: Kovach, Matthew James
Partner: UNT Libraries

Adaptive Power Management for Autonomic Resource Configuration in Large-scale Computer Systems

Description: In order to run and manage resource-intensive high-performance applications, large-scale computing and storage platforms have been evolving rapidly in various domains in both academia and industry. The energy expenditure consumed to operate and maintain these cloud computing infrastructures is a major factor to influence the overall profit and efficiency for most cloud service providers. Moreover, considering the mitigation of environmental damage from excessive carbon dioxide emission, the amount of power consumed by enterprise-scale data centers should be constrained for protection of the environment.Generally speaking, there exists a trade-off between power consumption and application performance in large-scale computing systems and how to balance these two factors has become an important topic for researchers and engineers in cloud and HPC communities. Therefore, minimizing the power usage while satisfying the Service Level Agreements have become one of the most desirable objectives in cloud computing research and implementation. Since the fundamental feature of the cloud computing platform is hosting workloads with a variety of characteristics in a consolidated and on-demand manner, it is demanding to explore the inherent relationship between power usage and machine configurations. Subsequently, with an understanding of these inherent relationships, researchers are able to develop effective power management policies to optimize productivity by balancing power usage and system performance. In this dissertation, we develop an autonomic power-aware system management framework for large-scale computer systems. We propose a series of techniques including coarse-grain power profiling, VM power modelling, power-aware resource auto-configuration and full-system power usage simulator. These techniques help us to understand the characteristics of power consumption of various system components. Based on these techniques, we are able to test various job scheduling strategies and develop resource management approaches to enhance the systems' power efficiency.
Date: August 2015
Creator: Zhang, Ziming
Partner: UNT Libraries

Addressing Multicultural Issues in the Counselor Education Classroom: a Phenomenological Analysis

Description: Multicultural education in counselor education is a popular topic among counselor educators and scholars. To date, scholars have focused on understanding the experiences of counselor educators who teach dedicated multicultural courses. However, less attention has been given to other counselor educators who are required by ethical and training standards to address multicultural issues across the curriculum. The purpose of this study was to understand counselor educators’ experiences addressing multicultural issues in courses that do not have a specific multicultural or diversity focus. I used phenomenological methodology to explore the experiences of counselor educators who hold doctoral degrees in counseling or a related field, have taken a multicultural/diversity course in their graduate training, are full-time clinical or tenure-line faculty members in CACREP-accredited programs, and have never taught courses dedicated to multicultural or diversity issues. Twelve participants (six men and six women), ranging in age ranged from 31 to 65, participated in the study. Ten participants identified as White, one African-American, and one Hispanic. The research team identified eight themes: (1) reasons for avoidance, (2) constraints, (3) qualities and practices, (4) educator as a factor in student development, (5) infusion, (6) personal background, (7) awareness of biases and assumptions, and (8) counselor educator responsibility/gatekeeping. Findings from this study will add to the literature regarding infusion of multicultural issues across the curriculum. Additionally, the implications offered will serve as a resource for counselor educators as they experience unique personal and professional challenges when addressing multicultural issues in classrooms beyond the main multicultural or diversity course offered in counseling programs. Implications for this study may lead to development of more focused guidelines on how to increase the increase the comfort of counselor educators as they facilitate multicultural discussions and assist counselors-in-training in working toward cultural competence.
Date: December 2015
Creator: Wagner, Terra M.
Partner: UNT Libraries

Addressing Social Elements of Wildfire: Risk, Response, and Recovery in Highland Village, TX

Description: Representatives of the City of Highland Village expressed concern over the risk of wildfires for their community. Anthropology provides many tools for and examples of disaster assessment of preparedness, response, recovery, and mitigation. These tools combined with Geographic Information Systems (GIS) can provide a holistic, cultural ecological look at how such a disaster may take place in the city. The project's methods included a detailed survey of preparedness steps which was analyzed using SPSS and also imported into ArcGIS for spatial analysis, and semi-formal, in-depth interviews with residents of the community regarding preparedness, response, and recovery. Residents fell into a middle category of preparedness, with the majority of participants considering or implementing a few recommended preparedness steps. Interview participants expressed respect for and trust of the city and first-responders, as well as a willingness to volunteer their help during response and recovery stages. Finally the American Community Survey showed that resident socioeconomic vulnerability was considerably low, and no action needed to be taken to advocate for at-risk individuals. Overall, the City of Highland Village showed a high resiliency to disaster. A wildfire likely will not have a major impact on the community as a whole, though the city may reduce the impact even further by informing the public of their risk, clearing natural areas of dead brush, sharing preparedness and evacuation information via social media and newsletters, and planning relief stations for those who may have been impacted.
Date: May 2016
Creator: MacKinnon, Jessica
Partner: UNT Libraries

ADHD Symptomology and Overweight Among College Men

Description: Attention deficit/hyperactivity disorder (ADHD) is a childhood disorder that often persists into adulthood. Among adults, ADHD is highly comorbid with addictive behaviors (e.g., substance abuse and dependence), and depressive disorders. Recently, an association between ADHD and obesity has been reported in the literature; emotional and binge eating may be “addictive behaviors” that contribute to weight gain in this population. The purpose of this study was to test competing models of the hypothesized link between ADHD symptomology and overweight. Specifically, in Model 1, symptoms of depression are expected to mediate the relationship between symptoms of impulsivity and inattention and emotional and binge eating which, in turn, leads to weight gain (i.e., increased BMI). In Model 2, however, the impulsive symptoms have direct relationships with emotional and binge eating in addition to being mediated by depressive symptoms. Structural equation modeling (SEM) was employed to test how the models fit the data of 790 college men. Both models fit the data well, with Model 2 being preferred because of its greater connection to theory. All paths were significant indicating that increased impulsive and inattentive symptoms predicted increased symptoms of depression that, in turn, predicted increased emotional/binge eating, which has a direct and positive relationship with increased BMI. Moreover, impulsive symptoms were also directly related to emotional/binge eating, suggesting different paths to overweight across ADHD subtypes. The findings of the current study elucidate the links between ADHD symptoms and overweight (i.e., increased BMI).
Date: December 2011
Creator: Johnson, Leslee M.
Partner: UNT Libraries

Adhesion and Surface Energy Profiles of Large-area Atomic Layers of Two-dimensional MoS2 on Rigid Substrates by Facile Methods

Description: Two-dimensional (2D) transition metal dichalcogenides (TMDs) show great potential for the future electronics, optoelectronics and energy applications. But, the studies unveiling their interactions with the host substrates are sparse and limits their practical use for real device applications. We report the facile nano-scratch method to determine the adhesion energy of the wafer scale MoS2 atomic layers attached to the SiO2/Si and sapphire substrates. The practical adhesion energy of monolayer MoS2 on the SiO2/Si substrate is 7.78 J/m2. The practical adhesion energy was found to be an increasing function of the MoS2 thickness. Unlike SiO2/Si substrates, MoS2 films grown on the sapphire possess higher bonding energy, which is attributed to the defect-free growth and less number of grain boundaries, as well as less stress and strain stored at the interface owing to the similarity of Thermal Expansion Coefficient (TEC) between MoS2 films and sapphire substrate. Furthermore, we calculated the surface free energy of 2D MoS2 by the facile contact angle measurements and Neumann model fitting. A surface free energy ~85.3 mJ/m2 in few layers thick MoS2 manifests the hydrophilic nature of 2D MoS2. The high surface energy of MoS2 helps explain the good bonding strength at MoS2/substrate interface. This simple adhesion energy and surface energy measurement methodology could further apply to other TMDs for their widespread use.
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Date: May 2016
Creator: Wu, Min
Partner: UNT Libraries

Adlerian Play Therapy: Effectiveness on Disruptive Behaviors of Early Elementary-Aged Children

Description: Approximately 20% of children experience serious mental health problems severe enough to meet diagnosis criteria, and less than one third of these children receive the services they need. Identifying effective school-based counseling interventions provides a viable and accessible solution, especially for families with financial barriers. This randomized, controlled outcome study examined the effectiveness of Adlerian play therapy (AdPT) compared to reading mentoring (RM) with 58 kindergarten through third grade students who qualified with clinical levels of disruptive behavior in the classroom. Participants were identified as 48% Latino, 33% European American, and 19% African American. Approximately four-fifths of participants were male. Children were randomly assigned to AdPT (experimental group) or RM (active control group) for 16 sessions of treatment. Children in both groups participated in twice weekly, individual, 30-minute interventions that took place in their schools. Results from a two (group) by two (repeated measures) split plot ANOVA indicated that, compared to the RM group over time, the AdPT group demonstrated statistically significant improvement on (a) disruptive behaviors in the classroom, as directly observed by objective raters and as reported by teachers, and (b) stress in the teacher-child relationship, as reported by teachers. Teachers and observers were blinded to children's treatment group assignment. AdPT demonstrated moderate to large effect sizes on all measures, indicating the practical significance of treatment. Further, 72% of children receiving AdPT improved from clinical/borderline levels of disruptive behavior problems to more normative functioning post-intervention, demonstrating the clinical significance of results. Whereas further research is warranted, results from this preliminary study are promising and support the use of AdPT in elementary schools to meet the needs of children exhibiting disruptive classroom behavior.
Date: August 2010
Creator: Meany-Walen, Kristin K.
Partner: UNT Libraries

Adolescent Behavior Problems and Interparental Conflict: the Moderating Role of Parent-child Attachment

Description: The current study examined the role that parent-child attachment plays in the relationship between marital conflict and the development of behavior problems in adolescents. To evaluate the hypothesis that attachment moderates this relationship, 57 families were recruited via e-mail invitation sent to families that participated in local church youth groups, school organizations, and a treatment program designed for adolescents with behavior problems. One custodial parent and his/her adolescent child completed an online or paper version of a survey consisting of the Achenbach’s Behavior Checklists, the Inventory of Parent and Peer Attachment, and the Children’s Perception of Interparental Conflict Scale. Hypotheses were evaluated using Baron and Kenny’s (1986) procedures to test moderating effects with multiple regression analyses. Mother attachment demonstrated a significant moderation effect between the intensity of interparental conflict and the parent’s report of externalizing behavior problems. Specifically, at low conflict intensity levels, relative to low attachment security, high attachment security was associated with fewer externalizing behavior problems, whereas at high intensities of interparental conflict high attachment security was associated with more externalizing behavior problems.
Date: December 2013
Creator: Daubs, Carlyn
Partner: UNT Libraries

Adolescent Task Management: Multitasking and Social Media in the Student Search Process

Description: This study examines adolescent students at an American international school and observes student use of social networking programs as well as physical actions in the search process. The study specifically observed multitasking behavior and organizational skills among students, as well as linkages made through social networking sites. Student observations, student interviews, analysis of Facebook entries, and a survey on multitasking yielded rich data. Students appear to be far more organized than previously suggested in the literature, and in this study, the organization proved to be largely self-taught. Students used their social networks to build a kind of group expertise that compensated for their youthful naivety. Students exhibited self-control within the search to the degree that they could focus on what they wanted to find, and they used heuristics—mental shortcuts—to achieve what they needed. Searches also suggest creativity in that students were flexible in their search methods and used a number of tools to gather information. Students could balance the needs of the academic or imposed search with their own online lives, meaning that they made compensations for social media and media multitasking when it was deemed necessary.
Date: August 2013
Creator: Kurtenbach, John
Partner: UNT Libraries

Adolescents' Social Networking Use and Its Relationship to Attachment and Mental Health

Description: Adolescents spend much of their time using the internet and electronic media. Since its inception, the use of online social networking (OSN) sites by adolescents continues to grow. With the proliferation of OSN, it is critical to examine how this activity affects psychological development, but better measurement tools are needed. As researchers struggle to keep up with this rapidly growing field, many gaps remain in the literature investigating the interrelations between adolescent's OSN use and mental health outcomes. Research examining the relationship between OSN and mental health outcomes, specifically depression and anxiety, has produced mixed results suggesting that other factors influence this association. A large research literature documents associations between attachment and mental health. Given that attachment also affects interpersonal communication, several studies have investigated links between attachment and OSN use in adult and college populations. Results indicated that even though attachment to father was independently related to anxiety and depression symptoms, it was not a significant moderator for mental health and OSN. Attachment to mother was a significant moderator for anxiety and depression and several OSN subscales. Based on this information, a greater focus on youth's interpersonal connection and social skills both online and offline may be beneficial when treating adolescents experiencing anxiety or depression.
Date: December 2016
Creator: Woolford, Brittany
Partner: UNT Libraries

The Adoption, Management, and Performance of Local Government Investment Pools: A Comparative Analysis of State Practices

Description: This dissertation examines the factors influencing a state’s decision to adopt a local government investment pool (LGIP), the institutional arrangements used in managing them, and the effect of the institutional types on LGIP performance. The dissertation extends the policy adoption theory with insights from investment theory to demonstrate that management credibility influences the likelihood of a state’s LGIP adoption. The study finds that the quality of financial management, the quality of professional leadership, proximate state neighbors who have previously adopted an LGIP, and economic factors determine a state’s proclivity to policy adoption. The dissertation also describes the institutional arrangements used in managing LGIPs and develops typologies based on their institutional arrangements. The dissertation compares LGIPs depending on the risk aversion of their institutional arrangements. The research extends the risk-return tradeoff in investment theory to LGIP institutional arrangements. The empirical findings show that LGIP institutional arrangement that has greater risk report higher performance. The dissertation also finds that competition in the LGIP market due to multiple vendors, and periods of economic recession account for higher performance because of higher risk-taking behaviors associated with them. This dissertation promotes public funds investment laws that emphasize prudent management of government finances and guides managers of the public purse on the types of institutional choices that optimize returns with minimal risk.
Date: May 2016
Creator: Nukpezah, Julius Atsu
Partner: UNT Libraries

The Adoption of Open Source Software in Uganda: a Pragmatist Approach to the Formation of a National Information Policy for a New Technology

Description: This exploratory research examined an information policy formation process for the adoption of open source software (OSS) in Uganda. Grounded in a pragmatist tradition, this theoretical and empirical study pursued a qualitative research approach with a triangulation of theoretical concepts, data collection, and analysis techniques in an iterative and interactive process. The design provided a powerful context to develop and conduct field activities in Kampala with a purposeful sample of 22 participants, 20 in interviews and 5 in a focus group discussion. The research design enhanced consistency in the evidence from the data, increased robustness in the results, and confidence in the findings. The results highlighted a vibrant ICT sector in Uganda, underlined the multiple stakeholders and their competing interests in the policy, revealed a lack of consensus between the government and OSS promoters on the meaning of OSS, and illuminated the benefits in the OSS model over proprietary software. The stakeholders' conflicting perceptions appear to be too far apart to allow meaningful progress and are derailing the policy. Unless their conflicting perceptions are resolved, the OSS policy will continue stagnating. The study fills critical information gaps in Uganda’s policy formation processes, provides timely and relevant information to holistically understand a complex policy formation stage to enable stakeholders to resolve their impasse and enact a law to embrace OSS. It breaks ground in information policy research in framing policy formation processes for new ICTs, such as OSS, as ideologically-oriented. The findings offer ideas to scholars and African countries to draw applicable lessons.
Date: May 2014
Creator: Muwanguzi, Samuel
Partner: UNT Libraries

Adoptive Parenthood: an Exploratory Study of the Influence of Pre-adoption Communication Satisfaction on Post-adoption Family Adjustment and Coping

Description: There are over a million adopted children in the United States, which makes up over 2% of the population. in spite of the fact that the majority of children are adopted into loving and caring homes, early life trauma puts them at higher risk for developing behavioral and emotional problems than non-adopted children. Due to these issues, many adoptive parents encounter post-adoption stress. This stress is often linked to minimal education regarding short- and long-term challenges associated with adoption. the adoption agency is likely the best group for addressing challenges, yet few researchers have studied adoption agency communication and adoptive parent adjustment. in this study I examined pre-adoption communication satisfaction, post-adoption adjustment (life change and parental adjustment), and coping strategies. Hypothesis 1 questioned the relationship between adoptive parents’ pre-adoption communication satisfaction with their social workers and post-adoption family adjustment; this hypothesis was supported only for problems related to home and work life adjustment. Hypothesis 2 predicted coping strategies would mediate the relationship between communication satisfaction and family adjustment. H2 was not supported for both life change and parental adjustment. Research Questions 1a and 1b inquired about the coping strategy that had an impact on life change and parental adjustment; escape-avoidance coping was most common for problems related to parental difficulty adjustment. a second research question was added post hoc; it questioned if special needs adopted children had an impact on family adjustment. Results indicated the special needs designation is related to home and work life adjustment. After discussing the theoretical and practical implications of this study, I offer limitations and directions for future research.
Date: May 2012
Creator: Seebeck, Lara N.
Partner: UNT Libraries

Adult Attachment, Acculturation and Help-seeking of Latino College Students

Description: Based on theoretical reasoning and empirical evidence, the present study examined the unique and shared effects of attachment anxiety, attachment avoidance, and acculturation on attitudes toward seeking professional help among Latino college students. The research participants included 149 bilingual Latino college students from a large, public southwestern university. Results of a multiple regression analysis indicated that attachment avoidance was positively associated with both the recognition of need for psychological help and stigma of seeking professional help. Acculturation to American society was found to be statistically insignificant in predicting help-seeking attitudes in this sample of the population. Findings from exploratory questions suggested that Latino individuals would most likely seek help from parents, close friends, and then professionals. This study suggested that Latino individuals with high attachment avoidance acknowledge the potential benefit of professional help-seeking but distrust the process of approaching others for help. Limitations, implications, and future research directions will be discussed.
Date: May 2015
Creator: Zamudio, Gabriel
Partner: UNT Libraries

Adult Attachment Patterns, Mental Representation of Self, and Faith: Mediators of Childhood Trauma and Affect-Behavior Regulations in Adulthood

Description: The purpose of this study was to investigate psychological mechanism by which four intra- and inter-personal characteristics of an individual (anxious and avoidant adult attachment patterns, images of self, and religious faith) mediate the relationship between childhood trauma and each of three affect-behavior regulation problems in adulthood (symptoms of depression, disordered eating behaviors, and substance abuse). A total of 401 college student participants completed a packet of 18 surveys including 10 surveys used in the present study. Structural equation modeling was used to test each of three hypothesized structural models (Depression, Eating Disturbances, and Substance Abuse). A series of multi-group analyses conducted to test if each of three hypothesized models is invariant across gender indicated no significant difference between females and males. Thus, the data were combined across gender to test for mediated effects in each of three hypothesized models. The results indicated: (a) for the hypothesized model for depression, anxious attachment patterns, avoidant attachment patterns, and negative self-images, but not religious faith, fully mediated the relationship between childhood trauma and symptoms of depression; (b) for the model for eating disturbances, anxious attachment and negative images of self, but not avoidant attachment and religious faith, fully mediated the association between childhood trauma and disordered eating behaviors; and (3) for the mode for substance abuse, anxious attachment and poor religious faith, but not avoidant attachment and negative self-images, fully mediated the relationship between childhood trauma and substance abuse. The findings of the present study have noteworthy implications for treatment. When clients who suffer from symptoms of depression, disordered eating behaviors, and/or substance abuse report a history of repetitive abuse and neglect by primary caregivers in childhood, clinicians need to assist clients in: (a) understanding an association of childhood maltreatment with affect-behavior regulation problems; (b) being aware of an impact of abuse ...
Date: December 2010
Creator: Han, GiBaeg
Partner: UNT Libraries

Adult Learning: Evaluation of Preferences for Technology and Learning Sources for Workplace Learning

Description: The purpose of this research was to provide an initial investigation of the preferences for both technology and learning sources that are available today in the modern workplace at a large financial institution with a national presence in the USA. In addition to the preferences of the participants, the research includes insights about the culture of the learning organization by using the Dimension of Learning Organization Questionnaire (DLOQ) and two preference surveys. The research methods used in this study are categorized as mixed methods and include both quantitative and qualitative methods. This study is nonpositivist and descriptive. It is based on a triangulation design method which is comprised of analysis from data obtained from the DLOQ and preference surveys, as well as semi-structured interviews with several survey participants. The results of the studies provide the foundational information for an extended quantitative analysis.
Date: December 2016
Creator: Kaiser, Robert Cresswell
Partner: UNT Libraries

Advanced Power Amplifiers Design for Modern Wireless Communication

Description: Modern wireless communication systems use spectrally efficient modulation schemes to reach high data rate transmission. These schemes are generally involved with signals with high peak-to-average power ratio (PAPR). Moreover, the development of next generation wireless communication systems requires the power amplifiers to operate over a wide frequency band or multiple frequency bands to support different applications. These wide-band and multi-band solutions will lead to reductions in both the size and cost of the whole system. This dissertation presents several advanced power amplifier solutions to provide wide-band and multi-band operations with efficiency improvement at power back-offs.
Date: August 2015
Creator: Shao, Jin
Partner: UNT Libraries

Advancements in Instrumentation for Fourier Transform Microwave Spectroscopy

Description: The efforts of my research have led to the successful construction of several instruments that have helped expand the field of microwave spectroscopy. The classic Balle-Flygare spectrometer has been modified to include two different sets of antenna to operate in the frequency ranges 6-18 GHz and 18-26 GHz, allowing it to function for a large range without having to break vacuum. This modified FTMW instrument houses two low noise amplifiers in the vacuum chamber to allow for the LNAs to be as close to the antenna as physically possible, improving sensitivity. A new innovative Balle-Flygare type spectrometer, the efficient low frequency FTMW, was conceived and built to operate at frequencies as low as 500 MHz through the use of highly curved mirrors. This is new for FTMW techniques that normally operate at 4 GHz or higher with only a few exceptions around 2 GHz. The chirped pulse FTMW spectrometer uses horn antennas to observe spectra that span 2 GHz versus the standard 1 MHz of a cavity technique. This instrument decreases the amount of time to obtain a large spectral region of relative correct intensity molecular transitions. A Nd:YAG laser ablation apparatus was attached to the classic Balle-Flygare and chirped pulse FTMW spectrometers. This allowed the study of heavy metal containing compounds. The instruments I constructed and the techniques I used have allowed the discovery of further insights into molecular chemistry. I have seen the effects of fluorinating an alkyl halide by determining the geometry of the carbon backbone of trans-1-iodoperfluoropropane and observing a ΔJ = 3 forbidden transition caused by a strong quadrupole coupling constant on this heavy molecule. The quadrupole coupling tensors of butyronitrile, a molecule observed in space, have been improved. The nuclear quadrupole coupling tensor of difluoroiodomethane was added to a list of variably fluorinated methyl ...
Date: August 2011
Creator: Dewberry, Christopher Thomas
Partner: UNT Libraries

Adventure Based Counseling: Exploring the Impact of Abc on Adaptive Functioning in High School Males

Description: The purpose of this study was to examine the impact of ABC on adaptive functioning in high school males. Specifically, a pretest/posttest, experimental design (N = 46; Caucasian = 26, Hispanic = 20) was used to examine the changes in adaptive and maladaptive functioning in ABC participants (n = 21) compared to those in a control/waitlist group (n = 25) as measured by the Behavior Assessment System for Children, second edition (BASC-2). Participants randomly assigned to the treatment group engaged in 10 ABC sessions. In order to better understand group process in ABC, I had experimental group participants complete the Group Climate Question Short form (GCQ-S) three times during the intervention. A mixed between/within subjects ANOVA of the BASC-2 scores revealed a statistically significant increase in adaptive functioning for both groups, F(1, 33) = 8.58, p < .01, with a partial eta squared of .21 indicating a large effect. There was no statistically significant difference between the experimental and control/waitlist groups, F(1, 33) = .064, p = .80, and a very small effect size (partial eta squared < .01). A repeated measures ANOVA of the GCQ-S scores revealed a statistically significant increase in engagement, F(2, 38) = 4.067, p = .025, with an eta squared of .21, indicating a large effect. Limitations of the study, implications of the results for practice, and recommendations for future research are presented.
Date: August 2013
Creator: Christian, David D.
Partner: UNT Libraries

Aerospace and Defense Industries Online Recruiting of College and University Graduates: Strategies Toward Defining a Comprehensive Informational Benchmark

Description: This qualitative, inductive study analyzed online recruiting information posted at the websites of five major aerospace and defense corporations to recruit college juniors, seniors, and recent graduates. Recruitment of this group is critical to staff the personnel for the scientific, technical, and management needs of aerospace and defense industries. The study sought: (1) to determine the use of multiple recruitment factors inferred from the literature and recommended for successful recruitment of college graduates, (2) to determine use of online social media (Facebook, Twitter, LinkedIn) to recruit this population, and (3) to explore commonalities among these corporations regarding online recruiting information to determine if a model for online recruitment now exists. A matrix of recruitment factors was developed from a review of the literature on the personnel needs of this industry and on effective recruiting factors for this group. Content analysis involved filtering information at each website with the matrix. Conclusions of this study include: (1) the matrix of recruitment factors and the rating scale developed for the purposes of this study provide a tool for researching, documenting, and comparing recruitment information on the internet; (2) that while these corporations represent the latest applications in technology in their manufacturing processes and products, they do not use social networking technology to the extent the popular and scholarly literature indicate is typical for the target group. Given that the current generation exhibits extensive use of social media, several of these corporations’ websites appear not to utilize this networking technology. Informally, these corporations argue that cyber-security prevents extensive use of social networking sites. Thus, these corporations must determine how to maintain cyber-security while at the same time adopting more accepted use of social networking platforms.
Date: August 2011
Creator: Holland, Marcia Annette
Partner: UNT Libraries