UNT Theses and Dissertations - 404 Matching Results

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The Choral Music of Ola Gjeilo: a New Vision of the Choral Instrument in the 21St Century

Description: The choral music of Norwegian composer Ola Gjeilo (pronounced “yay-loh”) is gaining international acclaim and is widely performed and commissioned by prominent high school, university, and professional choirs. It represents a philosophical approach and vision of the choral instrument for which the conductor must have a clear understanding in order to prepare a meaningful performance. in particular, his music merges diverse musical influences, which results in a product of unique character among choral compositions in the late 20th and early 21st centuries. Gjeilo draws inspiration from a text but then uses its sonic qualities (the sounds of vowels and consonants) to create an atmosphere of sound instead of following the traditions in choral and vocal music of using musical mechanisms (melody, rhythm, and harmony) to reinforce the text poetically. This study provides an overview of Gjeilo’s background, in Chapter 1, and discusses its influence on his compositional philosophy. Chapter 2 contains musical examples from selected works, which are used to illuminate unique attributes found in Gjeilo’s music. Chapter 3 presents important implications to consider aiding choral conductors in their preparation of future performances of Gjeilo’s music.
Date: May 2012
Creator: Schmidt, Brian A.
Partner: UNT Libraries

The Collective Pedagogy Utilized By the Trombone Instructors at the Rotterdam Conservatory of the Netherlands

Description: The Collective Pedagogy Utilized by the Trombone Instructors at the Rotterdam Conservatory of the Netherlands offers a comprehensive study of the collaboration between the various instructors of the trombone studio within the Rotterdam Conservatory and their pedagogical approach to curriculum, lesson structure, grading process, student body, and social environment. the Rotterdam Conservatory has produced some of the finest trombonists in the global music community. Alumni from the conservatory consistently win positions in professional ensembles, succeed in national and international competitions, and are often featured artists at international music festivals. the success of their alumni warrants closer scrutiny of the pedagogical approach utilized by the faculty of the conservatory.
Date: May 2012
Creator: Wallace, Noel James
Partner: UNT Libraries

Comparing the 2010 and 2011 Appic Match: Applicant Characteristics and Unmatched Applicant Distress

Description: The internship is one of the most important components of doctoral training in professional psychology. Given the serious problem of the internship imbalance, applicant and program characteristics that constitute a good “fit” with internship training programs have become of greater interest as securing an internship becomes a more competitive process. This study surveyed internship applicants from programs part of the Council of University Directors of Clinical Psychology (CUDCP), before and after the 2010 and 2011 match days. Number of interview offers was found to be the factor most consistently associated with successfully matching, and several other applicant characteristics salient to matching and obtaining interview offers were identified, including applicant personality. Additionally, personal accounts, but not empirical evidence, of going unmatched have attested to the psychological distress associated with this event. in the current study, while going unmatched was not found to be equitable to a traumatic stressor, evidence was found to support significant decrease in subjective well-being with respect to immediate distress. Findings are discussed in terms of the predictability of and implications for the match process and internship imbalance, and recommendations are made for future research directions.
Date: May 2012
Creator: Hogan, Lindsey R.
Partner: UNT Libraries

A Comparison of Mercury Localization, Speciation, and Histology in Multiple Fish Species From Caddo Lake, a Fresh Water Wetland

Description: This work explores the metabolism of mercury in liver and spleen tissue of fish from a methylmercury contaminated wetland. Wild-caught bass, catfish, bowfin and gar were collected. Macrophage centers, which are both reactive and primary germinal centers in various fish tissues, were hypothesized to be the cause of demethylation of methylmercury in fish tissue. Macrophage centers are differentially expressed in fish tissue based on phylogenetic lineage, and are found primarily in the livers of preteleostean fish and in the spleen of teleostean fish. Histology of liver and spleen was examined in both control and wild-caught fish for pathology, size and number of macrophage centers, and for localization of mercury. Total mercury was estimated in the muscle tissue of all fish by direct mercury analysis. Selenium and mercury concentrations were examined in the livers of wild-caught fish by liquid introduction inductively coupled plasma mass spectrometry (ICP-MS). Total mercury was localized in histologic sections by laser ablation ICP-MS (LA-ICP-MS). Mercury speciation was determined for inorganic and methylmercury in liver and spleen of fish by bas chromatography-cold vapor atomic fluorescence spectroscopy (GC-CVAFS). Macrophage center tissue distribution was found to be consistent with the literature, with a predominance of centers in preteleostean liver and in spleens of teleostean fish. Little evidence histopathology was found in the livers or spleens of fish examined, but differences in morphology of macrophage centers and liver tissue across species are noted. the sole sign of liver pathology noted was increased hepatic hemosiderosis in fish with high proportions of liver inorganic mercury. Inorganic mercury was found to predominate in the livers of all fish but bass. Organic mercury was found to predominate in the spleens of all fish. Mercury was found to accumulate in macrophage centers, but concentrations of mercury in this compartment were found to vary less in relation ...
Date: May 2012
Creator: Smith, James Durward
Partner: UNT Libraries

A Comparison of Vocabulary Banks and Scripts on Native English-speaking Students’ Acquisition of Italian

Description: The study applied behavior analytic principles to foreign language instruction in a college classroom. Two study methods, vocabulary banks and scripts, were compared by assessing the effects on Italian language acquisition, retention, and generalization. Results indicate that students without prior exposure to Italian engaged in more exchanges and emitted more words in script tests compared to vocabulary bank tests. Participants with at least two classes in Italian prior to the study engaged in more exchanges and emitted more words during vocabulary bank tests. Data suggest that different teaching strategies may work for different learners. More research is needed to determine efficient teaching methods and how to ascertain which approaches work best for learners with different histories.
Date: May 2012
Creator: Dean, Brittany L.
Partner: UNT Libraries

Consumer Perception of Brand Equity Measurement: a New Scale

Description: Brand equity is perhaps the most important marketing concept in both academia and practice. The term came into use during the late 1980s; and the importance of conceptualizing, measuring, and managing brand equity has grown rapidly in the eyes of practitioners and academics alike. This has resulted in several often-divergent view-points on the dimensions of brand equity, the factors that influence it, the perspectives from which it should be studied, and the ways to measure it. Many different definitions and ways to measure brand equity have been proposed, and most of them are based upon the definition: the added value with which a given brand endows a product. The two most influential conceptualizations of brand equity are Aaker and Keller. Aaker defines brand equity as a set of brand assets and liabilities linked to a brand, its name and symbol, that add to or subtract from the value provided by a product or service to a firm and/or to that firm’s customers. Keller defines consumer-based brand equity (CBBE) as the differential effect of brand knowledge on consumer response to the marketing of the brand. Currently, all research on brand equity has used the same conceptualization of the construct based on previously determined dimensions with no attempt to argue their validity. Given the importance of the concept of brand equity in marketing, as well as the need for the measurement of brand equity, the literature lacks an empirically based consumer-perceived brand equity scale. Since the brand is the consumer’s idea, the consumer is an active participant in the creation of equity for the brand. So if we want to understand and manage the intangible equity directly, we have to have the consumer’s help. This dissertation enriches and strengthens the current knowledge on brand equity by developing a new conceptualization and scale ...
Date: May 2012
Creator: Baalbaki, Sally Samih
Partner: UNT Libraries

Continuity of Caste: Free People of Color in the Vieux Carré of New Orleans, 1804-1820

Description: Because of its trademark racial diversity, historians have often presented New Orleans as a place transformed by incorporation into the American South following 1804. Assertions that a comparatively relaxed, racially ambiguous Spanish slaveholding regime was converted into a two-caste system of dedicated racial segregation by the advent of American assumption have been posited by scholars like Frank Tannenbaum, Gwendolyn Midlo Hall, and a host of others. Citing dependence on patronage, concubinage, and the decline in slave manumissions during the antebellum period, such studies have employed descriptions of the city’s prominent free people of color to suggest that the daily lives of non-whites in New Orleans experienced uniform restriction following 1804, and that the Crescent City’s transformation from Atlantic society with slaves to rigid slave society forced free people of color out of the heart of the city, known as the Vieux Carré, and into “black neighborhoods” on the margins of town. Despite the popularity of such generalized themes in the historiography, however, the extant sources housed in New Orleans’s valuable archival repositories can be used to support a vastly divergent narrative. By focusing on individual free people of color, or libres, rather than the non-white community as a whole, this paper seeks to show that free people of color were self determined in both public and private aspects of daily life, irrespective of governmental regime, and that their physical presence and political agency were not entirely eroded by the change in administration. Through evaluation of the geography of free black-owned properties listed in the city’s notarial archives, as well as baptisms, births, deaths, and marriages listed in archdiocese ledgers, I show that the family and community lives of free people of color in New Orleans’ oldest neighborhood appeared alive and well throughout the territorial period.
Date: May 2012
Creator: Foreman, Nicholas
Partner: UNT Libraries

Criticality in Cooperative Systems

Description: Cooperative behavior arises from the interactions of single units that globally produce a complex dynamics in which the system acts as a whole. As an archetype I refer to a flock of birds. As a result of cooperation the whole flock gets special abilities that the single individuals would not have if they were alone. This research work led to the discovery that the function of a flock, and more in general, that of cooperative systems, surprisingly rests on the occurrence of organizational collapses. In this study, I used cooperative systems based on self-propelled particle models (the flock models) which have been proved to be virtually equivalent to sociological network models mimicking the decision making processes (the decision making model). The critical region is an intermediate condition between a highly disordered state and a strong ordered one. At criticality the waiting times distribution density between two consecutive collapses shows an inverse power law form with an anomalous statistical behavior. The scientific evidences are based on measures of information theory, correlation in time and space, and fluctuation statistical analysis. In order to prove the benefit for a system to live at criticality, I made a flock system interact with another similar system, and then observe the information transmission for different disturbance values. I proved that at criticality the transfer of information gets the maximal efficiency. As last step, the flock model has been shown that, despite its simplicity, is sufficiently a realistic model as proved via the use of 3D simulations and computer animations.
Date: May 2012
Creator: Vanni, Fabio
Partner: UNT Libraries

Cuff-less Blood Pressure Measurement Using a Smart Phone

Description: Blood pressure is vital sign information that physicians often need as preliminary data for immediate intervention during emergency situations or for regular monitoring of people with cardiovascular diseases. Despite the availability of portable blood pressure meters in the market, they are not regularly carried by people, creating a need for an ultra-portable measurement platform or device that can be easily carried and used at all times. One such device is the smartphone which, according to comScore survey is used by 26.2% of the US adult population. the mass production of these phones with built-in sensors and high computation power has created numerous possibilities for application development in different domains including biomedical. Motivated by this capability and their extensive usage, this thesis focuses on developing a blood pressure measurement platform on smartphones. Specifically, I developed a blood pressure measurement system on a smart phone using the built-in camera and a customized external microphone. the system consists of first obtaining heart beats using the microphone and finger pulse with the camera, and finally calculating the blood pressure using the recorded data. I developed techniques for finding the best location for obtaining the data, making the system usable by all categories of people. the proposed system resulted in accuracies between 90-100%, when compared to traditional blood pressure meters. the second part of this thesis presents a new system for remote heart beat monitoring using the smart phone. with the proposed system, heart beats can be transferred live by patients and monitored by physicians remotely for diagnosis. the proposed blood pressure measurement and remote monitoring systems will be able to facilitate information acquisition and decision making by the 9-1-1 operators.
Date: May 2012
Creator: Jonnada, Srikanth
Partner: UNT Libraries

The Demographics of Corporal Punishment in Texas

Description: This dissertation examined the student discipline policies of 1,025 Texas school districts, as well as data from the Texas Education Agency’s Academic Excellence Indicator System in order to identify demographic patterns regarding corporal punishment policies in Texas schools. the study also studied the relationship between a district’s corporal punishment policy and student achievement. the dissertation utilized legal research methods and document analysis as its research methodology. Document analysis was the primary methodology used to answer the research questions whereby individual school district policies were identified and classified based on a number of demographic characteristics as well as the variations in corporal punishment policies among the various districts. the results of the study found that although more Texas school districts permit corporal punishment than have banned the practice, 60 percent of Texas school children go to school in districts where corporal punishment is not permitted. Corporal punishment is generally permitted in rural areas, with the majority of school districts in West Texas and the Texas Panhandle still allowing it by policy. a case study affirmed a finding from a national study regarding the type and locale of a student that is most likely disciplined using corporal punishment. the study determined that the larger Texas school districts have moved away from using corporal punishment as a disciplinary tactic. No district categorized as “Major Urban” by the Texas Education Agency permits corporal punishment of students. None of the larger districts categorized as “Urban” or “Major Suburban” that prohibit corporal punishment were identified as “Academically Unacceptable” under the State accountability system. This study also found that districts that prohibit corporal punishment and have a large number of minority students tend to have higher AEIS ratings. This study’s findings suggest that the elimination of corporal punishment in highly populated Texas school districts may be an ...
Date: May 2012
Creator: Phillips, Stephanie
Partner: UNT Libraries

Detection of Mercury Among Avian Trophic Levels at Caddo Lake and Lake Lewisville, TX

Description: Mercury (Hg) is a globally distributed toxicant that has been shown to have negative effects on birds. in the United States, avian taxa have been shown to possess high Hg concentrations in the northeast, Great Lakes and Everglades ecosystems; however, few studies have measured avian Hg concentrations in other geographic regions. Previous studies have documented high Hg concentrations in multiple organisms in east Texas, but birds were not included in these studies. the main objective of the present study was to quantify Hg concentrations in birds in differing trophic levels at Caddo Lake and Lake Lewisville, TX. Results suggest that Hg concentrations may be high enough to negatively impact some bird taxa, particularly those at high trophic levels, residing at both Caddo Lake and Lake Lewisville.
Date: May 2012
Creator: Schulwitz, Sarah Elizabeth
Partner: UNT Libraries

Devaluing Stigma in the Context of Forgiveness, Coping and Adaptation: a Structural Regression Model of Reappraisal

Description: The 2010 National HIV/AIDS Strategy outlined three important goals for managing the current HIV pandemic in the U.S.: (1) reduce the number of people who become infected with HIV; (2) improve access to health care and health-related outcomes for people living with HIV/AIDS (PLH/A); and (3) reduce HIV-related health disparities. Each of these goals tacitly depends upon reducing HIV-related stigma, and this study examined how HIV+ individuals evaluate coping efforts to overcome stigma’s impact on quality of life (QOL). a structural regression model was developed to instantiate the reappraisal process described by Lazarus and Folkman’s transactional theory of stress and coping, and this model indicated that maladaptive coping fully mediated the relationship between dispositional forgiveness and perceived stigma, which supports the prediction that coping efficacy is related to stress reduction. Additionally, maladaptive coping fully mediated the relationship between dispositional forgiveness and QOL, supporting the contention that forgiveness is a critical aspect to the evaluative process that influences how PLH/A cope with stigma. Lastly, the model showed that when PLH/A engaged in maladaptive coping to mitigate stress-related stigma, these individuals experienced increased stigmatization and reported significantly lower levels of health-related QOL. in contrast, PLH/A that reported higher levels of dispositional forgiveness were significantly less likely to use maladaptive coping to overcome stigma. Therefore, dispositional forgiveness works through coping to alter perceptions regarding stigmatization, while indirectly influencing attitudes related to health distress, mental health, and cognitive and social functioning. the theoretical and clinical implications of these findings are discussed.
Date: May 2012
Creator: Gates, Michael S.
Partner: UNT Libraries

The Development of Anti-submarine Warfare in the Mediterranean: the American Contribution and the Bombardment of Durazzo

Description: The Entente powers began World War I without any formal anti-submarine countermeasures. However, the Entente developed countermeasures through trial and error over time. Success was moderate until America joined the war. with America came the arrival of subchasers to the Mediterranean Theater of Operations. This highly specialized vessel helped turn the tide against U-boats. a true counter to the U-boat threat in the Mediterranean did not come until October 2, 1918 with the bombardment of Durazzo. This thesis discusses the development of Entente anti-submarine capabilities and illustrate how America's contribution led to success. a detailed analysis of the rarely discussed bombardment of Durazzo is included using archival documents.
Date: May 2012
Creator: Vaughan, Evan Michael
Partner: UNT Libraries

A Driver, Vehicle and Road Safety System Using Smartphones

Description: As vehicle manufacturers continue to increase their emphasis on safety with advanced driver assistance systems (ADAS), I propose a ubiquitous device that is able to analyze and advise on safety conditions. Mobile smartphones are increasing in popularity among younger generations with an estimated 64% of 25-34 year olds already using one in their daily lives. with over 10 million car accidents reported in the United States each year, car manufacturers have shifted their focus of a passive approach (airbags) to more active by adding features associated with ADAS (lane departure warnings). However, vehicles manufactured with these sensors are not economically priced while older vehicles might only have passive safety features. Given its accessibility and portability, I target a mobile smartphone as a device to compliment ADAS that can bring a driver assist to any vehicle without regards for any on-vehicle communication system requirements. I use the 3-axis accelerometer of multiple Android based smartphone to record and analyze various safety factors which can influence a driver while operating a vehicle. These influences with respect to the driver, vehicle and road are lane change maneuvers, vehicular comfort and road conditions. Each factor could potentially be hazardous to the health of the driver, neighboring public, and automobile and is therefore analyzed thoroughly achieving 85.60% and 89.89% classification accuracy for identifying road anomalies and lane changes, respectively. Effective use of this data can educate a potentially dangerous driver on how to operate a vehicle safely and efficiently. with real time analysis and auditory alerts of these factors, I hope to increase a driver's overall awareness to maximize safety.
Date: May 2012
Creator: Gozick, Brandon
Partner: UNT Libraries

Early College High School: Hispanic Students’ Perceptions and Experiences From a Texas Campus

Description: Early college high school (ECHS) is a dual enrollment program that allows high school students to earn college credits while in high school. ECHS was developed with the intention of attracting students to pursue a 4-year college degree, especially students who might not attend college without intervention. The program targets students from low-income families, students who have low academic achievement, and students from minority groups including Hispanics, African Americans, and Native Americans. The purpose of this study was to explore the perceptions and opinions of Hispanic students about their experiences in an ECHS, and to better understand how their ECHS experiences affected motivation to engage in academics. The expectancy theory and college-going culture provided the theoretical framework for this case study. Semi-structured interviews captured the experiences of the participants. The study focused on 10 Hispanic students, 5 seniors and 5 juniors, enrolled at an ECHS located on a community college campus in Texas. The study found that students with higher motivation to work at high school and college courses had several reasons for choosing to attend ECHS. The reasons included a chance to earn a high school diploma and associate’s degree simultaneously, free college tuition, and an accelerated program to get through college. The students also identified rewarding outcomes for completing college. Those outcomes included satisfying career, personal satisfaction, ability to provide for their family and making their family proud as the first high school graduate and college attendee. One student had a lower motivation to work at high school and college work. He chose to attend ECHS to seek more freedom than a traditional high school. He was not certain about graduating from high school and doubtful about college graduation. This study contributes to the ECHS literature by providing details on students’ experiences at an ECHS. Using the qualitative ...
Date: May 2012
Creator: Brenner, Rose K.
Partner: UNT Libraries

Early Literacy of Young Children in New Immigrant and Native Families in Taiwan: Educational and Socio-political Implications

Description: Because of shifting demographics, the Taiwanese government opened the country to immigrants from Southeast Asia. Foreign-born brides of Taiwanese men have contributed significantly to this trend of new immigration, inspiring fears that their children, inadequately prepared for the literacy requirements of early education, might negatively impact the educational system and society. to better understand the socio-political implications of this cultural shift, the researcher gathered data from one hundred and twenty immigrant and native families with first graders in six major cities in Taiwan. Purposes of this research are to: (a) investigate to what extent, if any parenting style is impacted by differences in immigration status between native Taiwanese and Southeast Asian immigrant mothers, (b) examine to what extent, if any maternal parenting styles relate to children’s early literacy, and (c) determine to what extent, if any maternal parenting styles along with the children’s and familial characteristics associate with children’s early literacy. the study found that (a) immigrant mothers are statistically lower on authoritative and higher on permissive parenting style than native mothers; (b) immigrant mothers’ participation in integration programs does not relate to maternal parenting styles or children’s literacy performances; (c) children from immigrant families are significantly lower than their peers from native families on receptive vocabulary and phonological awareness; (d) children from higher income families perform better on receptive vocabulary than their lower income peers; (e) children whose mothers are senior high school graduates achieve significantly better on literacy skills than others. Furthermore, children of mothers with higher education perform better on receptive vocabulary than those whose mothers have lower education levels; (f) there was little relationship between children’s literacy development and the three maternal parenting styles; (g) age and gender are the most significant predictors of children’s literacy development. the limited influence of parenting styles on childhood literacy ...
Date: May 2012
Creator: Wang, Hui-Fen
Partner: UNT Libraries

Ecological Significance and Underlying Mechanisms of Body Size Differentiation in White-tailed Deer

Description: Body size varies according to nutritional availability, which is of ecological and evolutionary relevance. The purpose of this study is to test the hypothesis that differences in adult body size are realized by increasing juvenile growth rate for white-tailed deer (Odocoileus virginianus). Harvest records are used to construct growth rate estimates by empirical nonlinear curve fitting. Results are compared to those of previous models that include additional parameters. The rate of growth increases during the study period. Models that estimate multiple parameters may not work with harvest data in which estimates of these parameters are prone to error, which renders estimates from complex models too variable to detect inter-annual changes in growth rate that this simpler model captures
Date: May 2012
Creator: Barr, Brannon
Partner: UNT Libraries

Ecology and Recolonization of Benthic Macroinvertebrates in a Groundwater-dependent Stream in North Central Texas During a Supra-seasonal Drought

Description: Extreme climatic events such as droughts are known to eliminate aquatic biota and alter community structure and function. Perennial headwater springs provide important drought refugia to benthic macroinvertebrates and an important source of colonists via drift or aerial adults to intermittent streams post-drought. During a supra-seasonal drought in North-central Texas summer and fall 2006, benthic macroinvertebrates from persistent groundwater-dependent macrohabitats of varying hydrological connectivity and riparian shading were studied: perennial riffles, connected pools, shaded disconnected pools, and full sun disconnected pools. Riffles were a distinct habitat with significantly higher taxa richness, proportion of lotic taxa, diversity and evenness than other macrohabitats. Macrohabitats were found to be important refugia for 106 benthic macroinvertebrates and 4 microcrustacean taxa. Throughout the extreme drought, perennially flowing habitats were refugia to 19 taxa (17.9% total taxa) not collected in disconnected pools. Shaded disconnected pools contained lotic taxa not previously known to be able to complete their lifecycles in lentic habitats, emphasizing the importance of groundwater effluent and shading. With the resumption of flow at a downstream intermittent site of Ash Creek in mid-October 2006, an annual recolonization study was conducted comparing the perennial headwaters’ benthic macroinvertebrate taxa richness, densities and community ecology with the downstream intermittent site. The headwaters supported higher mean taxa richness than the intermittent site over the duration of the study (ANOVA P < 0.001). However, the unexpected result of overall decreasing taxa richness at the perennial headwater site from August 2006 to April 2008 appears to reflect lag effects of the supra-seasonal drought combined with effects of multiple spates of 2007, which are factors confounding the point of recovery for taxa richness. Recovery of taxa richness at the intermittent site took 9 months compared to 1 to 2 months reported in other arid and semi-arid streams in the United States recovering ...
Date: May 2012
Creator: Burk, Rosemary A.
Partner: UNT Libraries

Effect of Age on Likelihood to Test for Hiv

Description: HIV/AIDS can affect individuals of any age. Efforts to educate those considered to be most at-risk, based on the age at which the most individuals are infected, are ongoing and public. Less work and mainstream education outreach, however, is being directed at an older population, who can be more likely to contract HIV, is more susceptible to the effects of HIV, and more likely to develop AIDS, than younger persons. Guided by the Health Belief Model theory, research was conducted to determine what, if any, relationship existed between age of an individual and the possibility that an HIV test will be sought. Factors of gender, education, ethnicity and marital status were included in analyses. the research indicated that as age increased, likelihood for getting an HIV test decreased. Overall, most individuals had not been tested for HIV. the implications of an aged and aging population with HIV include a need for coordinated service delivery, increased education and outreach.
Date: May 2012
Creator: Dreyer, Katherine
Partner: UNT Libraries

Effect of Resistance Training on Cytokines in Hiv+ Men with Chemical Dependence

Description: Human immunodeficiency virus (HIV) and substance abuse (drug and/or alcohol) independently impair the immune system; importantly, the combination of HIV infection and substance abuse might produce more than an additive effect on this system. Tumor necrosis factor-alpha (TNF-?) and Interferon gamma (IFN?) are pro-inflammatory cytokines involved in differentiation of Th0 cells into Th1 cells. Interleukin 4 (IL-4) and Interleukin 10 (IL-10) are anti-inflammatory cytokine involved in differentiation of Th0 cells to Th2 cells. Unbalanced Th1 and Th2 cells can lead to immune suppression. Thus, changes in these cytokines could have important implications for people infected with HIV (HIV+). Resistance training can counteract muscle wasting, improve strength, and improve muscle mass. The purpose of this study was to examine the effect of resistance training on resting concentrations of circulating TNF-?, IFN-?, IL-4, and IL-10. Sixteen men (42 ± 11 years, 180.4 ± 9.1 cm, 89.2 ± 20.7 kg) infected with HIV and enrolled in an intensive 60-day in-patient substance addiction/abuse treatment program were recruited shortly after admission to the treatment facility. Participants were assigned to one of two groups using randomization: supervised resistance exercise 3 times per week using a progressive and non-linear periodized program (Exercise) or no exercise training (Non-Exercise) for six weeks. Before (Pre) and after (Post) the 6-week period, resting and fasted blood samples were obtained and analyzed for serum TNF-?, IFN-?, IL-4, and IL-10 concentrations using a high-sensitivity ELISA. TNF-? did not change following the 6-week period for Exercise (Pre: 4.8 ± 2.7 pg·ml-1; Post: 4.6 ± 2.4 pg·ml-1) or Non-Exercise (Pre: 3.0 ± 1.3 pg·ml-1; Post: 2.7 ± 0.8 pg·ml-1). IFN-?, IL-4, and IL-10 concentrations were below detectable limits. No adverse effects of the intervention were reported. A six-week resistance training program does not elicit changes in circulating TNF-? concentrations in men infected with HIV and ...
Date: May 2012
Creator: Curtis, John Harper
Partner: UNT Libraries

Effects of Dissipation on Propagation of Surface Electromagnetic and Acoustic Waves

Description: With the recent emergence of the field of metamaterials, the study of subwavelength propagation of plane waves and the dissipation of their energy either in the form of Joule losses in the case of electomagnetic waves or in the form of viscous dissipation in the case of acoustic waves in different interfaced media assumes great importance. with this motivation, I have worked on problems in two different areas, viz., plasmonics and surface acoustics. the first part (chapters 2 & 3) of the dissertation deals with the emerging field of plasmonics. Researchers have come up with various designs in an efort to fabricate efficient plasmonic waveguides capable of guiding plasmonic signals. However, the inherent dissipation in the form of Joule losses limits efficient usage of surface plasmon signal. a dielectric-metal-¬dielectric planar structure is one of the most practical plasmonic structures that can serve as an efficient waveguide to guide electromagnetic waves along the metal-dielectric boundary. I present here a theoretical study of propagation of surface plasmons along a symmetric dielectric-metal-dielectric structure and show how proper orientation of the optical axis of the anisotropic substrate enhances the propagation length. an equation for propagation length is derived in a wide range of frequencies. I also show how the frequency of coupled surface plasmons can be modulated by changing the thickness of the metal film. I propose a Kronig-Penny model for the plasmonic crystal, which in the long wavelength limit, may serve as a homogeneous dielectric substrate with high anisotropy which do not exist for natural optical crystals. in the second part (chapters 4 & 5) of the dissertation, I discuss an interesting effect of extraordinary absorption of acoustic energy due to resonant excitation of Rayleigh waves in a narrow water channel clad between two metal plates. Starting from the elastic properties of the ...
Date: May 2012
Creator: Nagaraj, Nagaraj
Partner: UNT Libraries

Effects of Layer Double Hydroxide Nanoclays on the Toxicity of Copper to Daphnia Magna

Description: Nanoparticles may affect secondary pollutants such as copper. Layer Double Hydroxides (LDH) are synthetically produced nanoparticles that adsorb copper via cation exchange. Pretreatment of copper test solutions with LDH nanoparticles followed by filtration removal of LDH nanoparticles demonstrated the smallest LDH aggregates removed the most copper toxicity. This was due to increased surface area for cation exchange relative to larger particle aggregates. Co-exposure tests of copper chloride and clay were run to determine if smaller clay particles increased copper uptake by D. magna. Coexposure treatments had lower LC50 values compared to the filtration tests, likely as a result of additive toxicity. LDH nanoclays do reduce copper toxicity in Daphnia magna and may serve as a remediation tool.
Date: May 2012
Creator: Blake, Deanne Renee
Partner: UNT Libraries

The Effects of Textual Fluency on the Rate of Acquisition and Application of Intraverbal Relations

Description: Intraverbal behavior governs core elements of academic and intellectual behavior. These intraverbal relations can be explicitly taught when an individual is prompted to provide an appropriate response with pictures, text, or other stimuli following a verbal stimulus. It is possible that a focus on fluency of the target repertoires may lead to more conclusive data. the current study assessed the effects of precision teaching based instruction for component textual repertoires on the acquisition of intraverbal relations. Specifically, this study compared the effectiveness of two textual prompting procedures (with and without fluency-based instruction) on the acquisition and application of intraverbal relations using time-delay and a carefully controlled set of intraverbal stimuli. Results indicate that the use of textual prompts and an errorless time-delay transfer of stimulus control procedure were effective strategies for teaching intraverbal responses regardless of the inclusion of fluency-based instruction.
Date: May 2012
Creator: Shrontz, Rachael E.
Partner: UNT Libraries

Electrochemical Depostion of Bismuth on Ruthenium and Ruthenium Oxide Surfaces

Description: Cyclic voltammetry experiments were performed to compare the electrodeposition characteristics of bismuth on ruthenium. Two types of electrodes were used for comparison: a Ru shot electrode (polycrystalline) and a thin film of radio-frequency sputtered Ru on a Ti/Si(100) support. Experiments were performed in 1mM Bi(NO3)3/0.5M H2SO4 with switching potentials between -0.25 and 0.55V (vs. KCl sat. Ag/AgCl) and a 20mV/s scan rate. Grazing incidence x-ray diffraction (GIXRD) determined the freshly prepared thin film electrode was hexagonally close-packed. After thermally oxidizing at 600°C for 20 minutes, the thin film adopts the tetragonal structure consistent with RuO2. a hydrated oxide film (RuOx?(H2O)y) was made by holding 1.3V on the surface of the film in H2SO4 for 60 seconds and was determined to be amorphous. Underpotential deposition of Bi was observed on the metallic surfaces and the electrochemically oxidized surface; it was not observed on the thermal oxide.
Date: May 2012
Creator: Taylor, Daniel M.
Partner: UNT Libraries