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 Degree Level: Master's
 Collection: UNT Theses and Dissertations
An Accelerometer-based Gesture Recognition System for a Tactical Communications Application
In modern society, computers are primarily interacted with via keyboards, touch screens, voice recognition, video analysis, and many others. For certain applications, these methods may be the most efficient interface. However, there are applications that we can conceive where a more natural interface could be convenient and connect humans and computers in a more intuitive and natural way. These applications are gesture recognition systems and range from the interpretation of sign language by a computer to virtual reality control. This Thesis proposes a gesture recognition system that primarily uses accelerometers to capture gestures from a tactical communications application. A segmentation algorithm is developed based on the accelerometer energy to segment these gestures from an input sequence. Using signal processing and machine learning techniques, the segments are reduced to mathematical features and classified with support vector machines. Experimental results show that the system achieves an overall gesture recognition accuracy of 98.9%. Additional methods, such as non-gesture recognition/suppression, are also proposed and tested. digital.library.unt.edu/ark:/67531/metadc822779/
Anger, Forgiveness and Mindfulness: Correlates of Perceived Stress in an Lgb Sample
A sexual minority is someone who identifies as lesbian, gay or bisexual (LGB). According to the Minority Stress Model (Meyer, 2003), sexual minorities encounter significant levels of stress due to their minority group status, thus they are more likely to experience perceived stress. Our cross-sectional, correlational study aimed to explore the relationships between forgiveness, mindfulness and anger and how they are related to perceived stress in a convenience sample of ethnically diverse LGB adults. We hypothesized that: 1) anger is positively associated with perceived stress; 2) forgiveness is negatively associated with perceived stress; 3) mindfulness is negatively associated with perceived stress; and 4) anger, forgiveness and mindfulness account for a significant proportion of the variance in perceived stress. 5) The relationship between anger and perceived stress is moderated by forgiveness. 6) The relationship between anger and perceived stress is moderated by mindfulness. Among LGB adults, the extant literature does not address these four variables in conjunction and the relationships between anger, forgiveness, mindfulness and stress has yet to be explored. Various statistical analyses were conducted, including a hierarchical linear regression to test our model. We found that our overall model accounted for 36% of the total variance in perceived stress (F(5, 142) = 17.31, p <.01) with anger (β = .31, t = 3.55, p = .001) and forgiveness (β = -.21, t = -2.56, p < .05) as the significant predictors. Contrary to prediction, forgiveness and mindfulness did not moderate the relationship between anger and perceived stress in our LGB sample. Limitations, strengths, future research and implications are discussed. digital.library.unt.edu/ark:/67531/metadc822763/
Anisotropic Nature of Radially Strained Metal Tubes
Metal pipes are sometimes swaged by a metal cone to enlarge them, which increases the strain in the material. The amount of strain is important because it affects the burst and collapse strength. Burst strength is the amount of internal pressure that a pipe can withstand before failure, while collapse strength is the amount of external pressure that a pipe can withstand before failure. If the burst or collapse strengths are exceeded, the pipe may fracture, causing critical failure. Such an event could cost the owners and their customers millions of dollars in clean up, repair, and lost time, in addition to the potential environmental damage. Therefore, a reliable way of estimating the burst and collapse strength of strained pipe is desired and valuable. The sponsor currently rates strained pipes using the properties of raw steel, because those properties are easily measured (for example, yield strength). In the past, the engineers assumed that the metal would be work-hardened when swaged, so that yield strength would increase. However, swaging introduces anisotropic strain, which may decrease the yield strength. This study measured the yield strength of strained material in the transverse and axial direction and compared them to raw material, to determine the amount of anisotropy. This information will be used to more accurately determine burst and collapse ratings for strained pipes. More accurate ratings mean safer products, which will minimize risk for the sponsor’s customers. Since the strained metal has a higher yield strength than the raw material, using the raw yield strength to calculate burst and collapse ratings is a conservative method. The metal has even higher yield strength after strain aging, which indicates that the stresses are relieved. Even with the 12% anisotropy in the strained and 9% anisotropy in the strain aged specimens, the raw yield strengths are lower and therefore more conservative. I recommend that the sponsor continue using the raw yield strength to calculate these ratings. I set out to characterize the anisotropic nature of swaged metal. As expected, the tensile tests showed a difference between the axial and transverse tensile strength. The correlation was 12% difference in yield strength in the axial and transverse directions for strained material and 9% in strained and aged material. This means that the strength of the metal in the hoop (transverse) direction is approximately 10% stronger than in the axial direction, because the metal was work hardened during the swaging process. Therefore, the metal is more likely to fail in axial tension than in burst or collapse. I presented the findings from the microstructure examination, standard tensile tests, and SEM data. All of this data supported the findings of the mini-tensile tests. This information will help engineers set burst and collapse ratings and allow material scientists to predict the anisotropic characteristics of swaged steel tubes. digital.library.unt.edu/ark:/67531/metadc822747/
Assessment of Hot and Cool Executive Functioning Following Trauma Using the Traditional Stroop Task, Emotional Stroop Task, and a Novel Implicit Association Test
Individuals who have experienced a traumatic event and develop Post-Traumatic Stress Disorder (PTSD) frequently show deficits in both primarily “cool” and “hot” cognitive executive functions (e.g., traditional & emotional Stroop tasks, respectively) that can be impacted by high affective salience. Given the dimensional nature of psychopathology, questions remain about individuals within the general population who have experienced trauma but do not meet full criteria for PTSD and yet may manifest problems in these areas, especially areas of hot and cool executive functioning (EF). Thus, the current project was designed to assess hot and cool EF in a relatively large sample of individuals from the general population who have experienced trauma and currently demonstrate sub-clinical levels of post-traumatic symptoms. The Stroop task, Emotional Stroop task, and a novel modified Implicit Association Test were utilized to assess EF across a spectrum of individuals with varying traumatic histories and level of post-traumatic symptoms. Results suggest that a greater frequency of trauma experiences was moderately associated with worse performance on both hot and cool executive functioning measures. Specifically, females within the sample evidenced a close relationship between traumatic experiences, post-trauma symptoms, and executive functioning. Clinical and theoretical implications are discussed. digital.library.unt.edu/ark:/67531/metadc822731/
Characterization of Ti-6al-4v Produced Via Electron Beam Additive Manufacturing
In recent years, additive manufacturing (AM) has become an increasingly promising method used for the production of structural metallic components. There are a number of reasons why AM methods are attractive, including the ability to produce complex geometries into a near-net shape and the rapid transition from design to production. Ti-6Al-4V is a titanium alloy frequently used in the aerospace industry which is receiving considerable attention as a good candidate for processing via electron beam additive manufacturing (EBAM). The Sciaky EBAM method combines a high-powered electron beam, weld-wire feedstock, and a large build chamber, enabling the production of large structural components. In order to gain wide acceptance of EBAM of Ti-6Al-4V as a viable manufacturing method, it is important to understand broadly the microstructural features that are present in large-scale depositions, including specifically: the morphology, distribution and texture of the phases present. To achieve such an understanding, stereological methods were used to populate a database quantifying key microstructural features in Ti-6Al-4V including volume fraction of phases, a lath width, colony scale factor, and volume fraction of basket weave type microstructure. Microstructural features unique to AM, such as elongated grains and banded structures, were also characterized. Hardness and tensile testing were conducted and the results were related to the microstructural morphology and sample orientation. Lastly, fractured surfaces and defects were investigated. The results of these activities provide insight into the process-structure-properties relationships found in EBAM processed Ti-6Al-4V. digital.library.unt.edu/ark:/67531/metadc822771/
Comparative Analysis and Implementation of High Data Rate Wireless Sensor Network Simulation Frameworks
This thesis focuses on developing a high data rate wireless sensor network framework that could be integrated with hardware prototypes to monitor structural health of buildings. In order to better understand the wireless sensor network architecture and its consideration in structural health monitoring, a detailed literature review on wireless sensor networks has been carried out. Through research, it was found that there are numerous simulation software packages available for wireless sensor network simulation. One suitable software was selected for modelling the framework. Research showed that Matlab/Simulink was the most suitable environment, and as a result, a wireless sensor network framework was designed in Matlab/Simulink. Further, the thesis illustrates modeling of a simple accelerometer sensor, such as those used in wireless sensor networks in Matlab/Simulink using a mathematical description. Finally, the framework operation is demonstrated with 10 nodes, and data integrity is analyzed with cyclic redundancy check and transmission error rate calculations. digital.library.unt.edu/ark:/67531/metadc822834/
The Countess of Counter-revolution: Madame Du Barry and the 1791 Theft of Her Jewelry
Jeanne Bécu, an illegitimate child from the Vaucouleurs area in France, ascended the ranks of the Ancien régime to become the Countess du Barry and take her place as Royal Mistress of Louis XV. During her tenure as Royal Mistress, Jeanne amassed a jewel collection that rivaled all private collections. During the course of the French Revolution, more specifically the Reign of Terror, Jeanne was forced to hatch a plot to secure the remainder of her wealth as she lost a significant portion of her revenue on the night of 4 August 1789. To protect her wealth, Jeanne enlisted Nathaniel Parker Forth, a British spy, to help her plan a fake jewel theft at Louveciennes so that she could remove her economic capital from France while also reducing her total wealth and capital with the intent of reducing her tax payments. As a result of the theft, her jewelry was transported to London, where she would travel four times during the French Revolution on the pretext of recovering her jewelry. This thesis examines her actions while abroad during the Revolution and her culpability in the plot. While traveling to and from London, Jeanne was able to move information, money, and people out of France. Jeanne was arrested and charged with aiding the counter-revolution, for which the Revolutionary Tribunal sentenced her to death. Madame du Barry represented the extravagance and waste of Versailles and of Bourbon absolutism, and this symbolic representation of waste was what eventually inhibited Jeanne’s success. digital.library.unt.edu/ark:/67531/metadc822775/
Creating Community in Isolation: the History of Corpus Christi’s Molina Addition, 1954-1970
“Creating Community in Isolation: The History of Corpus Christi’s Molina Addition, 1954-1970” examines the history of the Molina Addition in Corpus Christi, Nueces County, Texas, and its serving district, the West Oso Independent School District, from 1954 to 1970. Specifically, this essay begins with an analysis of the elite-driven campaign to annex the blighted Molina Addition in September and October 1954. The city intended to raze the neighborhood and develop middle-class homes in place of the newly annexed neighborhood. Following the annexation of the Molina Addition, African American and ethnic Mexican residents initiated protracted struggles to desegregate and integrate schools that served their area, the West Oso Independent School District, as detailed in the chapter, “The West Oso School Board Revolution.” The chapter examines the electoral “revolution” in which Anglo rural elites were unseated from their positions on the school board and replaced by African American and ethnic Mexican Molina Addition residents. The third chapter, “Building Mo-Town, Texas,” focuses on residents’ struggle to install indoor plumbing, eliminate pit privies, construct paved roads, and introduce War on Poverty grants to rehabilitate the neighborhood. This chapter also offers a glimpse into the social life of Molina youth during the 1960s. digital.library.unt.edu/ark:/67531/metadc822818/
Decoding the Formation of a Retail Giant: the Evolving Geography of Costco’s Store Network
Although Costco operates over 580 warehouse stores throughout North America, their location strategy remains relatively unexamined in the economic geography literature. A cursory examination of Costco’s network makes it clear that the firm chooses to locate primarily in the suburbs of major cities, where income levels are somewhat higher than the national average. However, what is not clear is the extent to which other demographic and geographic factors adequately account for Costco’s store locations, and what strategy underlies the geography of the firm’s warehouse stores, especially in relation to its distribution network. This research studies Costco in order to decode the location strategies that have guided the company’s North American and international expansions. The investigation attempts to identify key elements of Costco’s multinational retail network, including this network’s evolution over time. This paper seeks to benefit both retail business and public policymakers by highlighting elements of Costco’s location strategy that have contributed to the firm’s success. digital.library.unt.edu/ark:/67531/metadc822836/
Determinants of Effort and Associated Cardiovascular Response to a Behavioral Restraint Challenge
This study directly tested implications of motivation intensity theory on effort to restrain against a behavioral urge or impulse (i.e. restraint intensity). Two factors were manipulated—magnitude of an urge and the importance of successfully resisting it—with cardiovascular (CV) responses related to active coping measured. Male and female undergraduate students were presented with a mildly- or strongly evocative film clip with instructions to refrain from showing any facial response. Success was made more or less important through coordinated manipulations of outcome expectancy, ego-involvement, and performance assessment. As expected, systolic blood pressure responses assessed during the performance period were proportional to the evocativeness of the clip when importance was high, but low regardless of evocativeness when importance was low. These findings support a new conceptual analysis concerned with the determinants and CV correlates of restraint intensity. Implications of the study and associations with current self-regulatory literature are discussed. digital.library.unt.edu/ark:/67531/metadc822752/
Determining the Emissivity of Roofing Samples: Asphalt, Ceramic and Coated Cedar
The goal is to perform heat measurements examine of selected roofing material samples. Those roofing materials are asphalt shingles, ceramics, and cedar. It’s important to understand the concept of heat transfer, which consists of conduction, convection, and radiation. Research work was reviewed on different infrared devices to see which one would be suitable for conducting my experiment. In this experiment, the main focus was on a specific property of radiation. That property is the emissivity, which is the amount of heat a material is able to radiate compared to a blackbody. An infrared measuring device, such as the infrared camera was used to determine the emissivity of each sample by using a measurement formula consisting of certain equations. These equations account for the emissivity, transmittance of heat through the atmosphere and temperatures of the samples, atmosphere and background. The experiment verifies how reasonable the data is compared to values in the emissivity table. A blackbody method such as electrical black tape was applied to help generate the correct data. With this data obtained, the emissivity was examined to understand what factors and parameters affect this property of the materials. This experiment was conducted using a suitable heat source to heat up the material samples to high temperature. The measurements were taken during the experiment and displayed by the IR camera. The IR images show the behavior of surface temperatures being distributed throughout the different materials. The main challenge was to determine the most accurate emissivity values for all material samples. The results obtained by the IR camera were displayed in figures and tables at different distances, which was between the heap lamp and materials. The materials exhibited different behaviors in temperature and emissivity at certain distances. The emissivity of each material varied with different temperatures. The results led to suggestions of certain materials that could be beneficial and disadvantageous in energy and cost savings during cold and hot seasons of the year. Also this led to some uncertainties in the data generated. Overall, this can support in exploring other ideas to increase energy and cost saving consistently during both season by using a material that can change its color and density based on a high or low temperature. digital.library.unt.edu/ark:/67531/metadc822838/
Direct Strength Method for Web Crippling of Cold-formed Steel C and Z Sections Subjected to Interior One Flange Loading and End One Flange Loading
The main objective of this research is to extend the “Direct strength method” for determining the web crippling strength of cold-formed steel C and Z sections subjected to End one flange loading and Interior one flange loading conditions. Direct strength method is applied for designing the columns and beams earlier. The existing specifications equation for calculating the web crippling strength of cold-formed steels designed by American Institute of Iron and Steel is very old method and it is based on the extensive experimental investigations conducted at different universities. Calculating the web crippling strength of cold-formed steels using direct strength method is a new technique. In the present research the web crippling strength of cold-formed steels were calculated using Direct Strength Method. The experimental data is collected from the tests that were conducted at different universities. The critical buckling strength of the members were calculated using Abaqus. Microsoft excel is used to generate the equations. The safety and resistance factors for the designed equations were calculated using “Load and resistance factor design” and “Allowable strength design” from North American Cold-Formed Steel Specification, 2012 edition book. digital.library.unt.edu/ark:/67531/metadc822839/
Dynamic Behaviors of Historical Wrought Iron Truss Bridges – a Field Testing Case Study
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Civil infrastructure throughout the world serves as main arteries for commerce and transportation, commonly forming the backbone of many societies. Bridges have been and remain a crucial part of the success of these civil networks. However, the crucial elements have been built over centuries and have been subject to generations of use. Many current bridges have outlived their intended service life or have been retrofitted to carry additional loads over their original design. A large number of these historic bridges are still in everyday use and their condition needs to be monitored for public safety. Transportation infrastructure authorities have implemented various inspection and management programs throughout the world, mainly visual inspections. However, careful visual inspections can provide valuable information but it has limitations in that it provides no actual stress-strain information to determine structural soundness. Structural Health Monitoring (SHM) has been a growing area of research as officials need to asses and triage the aging infrastructure with methods that provide measurable response information to determine the health of the structure. A rapid improvement in technology has allowed researchers to start using new sensors and algorithms to understand the structural parameters of tested structures due to known and unknown loading scenarios. One of the most promising methods involves the use of wireless sensor nodes to measure structural responses to loads in real time. The structural responses can be processed to help understand the modal parameters, determine the health of the structure, and potentially identify damage. For example, modal parameters of structures are typically used when designing the lateral system of a structure. A better understanding of these parameters can lead to better and more efficient designs. Usually engineers rely on a finite element analysis to identify these parameters. By observing the actual parameters displayed during field testing, the theoretical FE models can be validated for accuracy. This paper will present the field testing of a historic wrought iron truss bridge, in a case study, to establish a repeatable procedure to be used as reference for the testing of other similar structures. digital.library.unt.edu/ark:/67531/metadc822751/
Effect of Alloy Composition, Free Volume and Glass Formability on the Corrosion Behavior of Bulk Metallic Glasses
Bulk metallic glasses (BMGs) have received significant research interest due to their completely amorphous structure which results in unique structural and functional properties. Absence of grain boundaries and secondary phases in BMGs results in high corrosion resistance in many different environments. Understanding and tailoring the corrosion behavior can be significant for various structural applications in bulk form as well as coatings. In this study, the corrosion behavior of several Zr-based and Fe-Co based BMGs was evaluated to understand the effect of chemistry as well as quenched in free volume on corrosion behavior and mechanisms. Presence of Nb in Zr-based alloys was found to significantly improve corrosion resistance due to the formation of a stable passive oxide. Relaxed glasses showed lower rates compared to the as-cast alloys. This was attributed to lowering of chemical potential from the reduced fraction of free volume. Potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) techniques helped in quantifying the corrosion rate and polarization resistance. The effect of alloy composition was quantified by extensive surface analysis using Raman spectroscopy, energy dispersive x-ray spectroscopy and auger spectroscopy. Pitting intensity was higher in the as-cast glasses than the relaxed glasses. The electrochemical behavior of a Zr-Ti-Cu-Ni-Be bulk metallic glass subjected to high strain processing was studied. High strain processing caused shear band formation and an increase in the free volume. Potentiodynamic polarization and EIS showed a strong correlation between the enthalpy of structural relaxation and corrosion rate and polarization resistance. Pitting was observed to preferentially occur on shear bands in the processed samples, while it was stochastic in unprocessed glass. The corrosion analysis of Co-Fe glasses showed an increase in corrosion current density when Fe content was increased from 0 to 7 at%. The corrosion resistance improved when Fe content was further increased to 15 at%. Similar trend was seen in EIS studies. The improved corrosion resistance at 15 at% Fe can be attributed to the large supercooled region that facilitates the formation of completely amorphous alloy, in contrast to lower Fe containing alloys, where short range ordering may deteriorate the corrosion resistance. Porous metallic glass structure was developed by electrochemical dealloying via cyclic voltammetry. Mechanical properties and changes in electrical conductivity were measured as a function of depth from surface by nano-indentation and nano electrical contact resistance technique. The nanoporous layer was found have hardness of 0.41 GPa and elastic modulus of nearly 22 GPa. The resistivity of the nanoporous layer continuously decreased when moving towards the substrate as the indentation depth increased which is attributed to the gradient in pore size. digital.library.unt.edu/ark:/67531/metadc822824/
The Effect of Post-exercise Ethanol Consumption on the Acute Hormonal Response to Heavy Resistance Exercise in Women
The purpose of this study was to examine the hormonal response to acute ethanol ingestion following a bout of heavy resistance exercise in women. Eight resistance trained women completed two identical acute heavy resistance exercise tasks (AHRET). From 10-20 minutes post-AHRET, participants consumed either a grain ethanol or a placebo beverage. Blood was collected before (PRE) and immediately after the AHRET (IP) and then every 20 minutes for five hours. Blood collected after beverage ingestion was pooled into 3 batches (phases: 20-40 minutes, 60-120 minutes, and 140-300 minutes post-exercise) and analyzed for serum total testosterone (TT), free testosterone (FT), insulin-like growth factor-I (IGF-I), human growth hormone (GH), cortisol (COR), and estradiol (E2) concentrations. Circulating concentrations of TT were significantly greater at P20-40 than at PRE, P60-120, and P140-300. Circulating concentrations of FT were significantly greater at P20-40 than at all other times. Circulating concentrations of GH were significantly greater at IP than at PRE, P60-120, and P140-300. Circulating concentrations of COR were significantly greater at P20-40 than at all other times. Additionally, COR concentrations at P140-300 were significantly lower than at all other times. Circulating concentrations of IGF-1 were significantly greater at P20-40 than at P60-120 and P140-300. Circulating concentrations of E2 were significantly greater at P20-40 than at all other times. In summary, the present study demonstrated an acute modulation of the neuroendocrine milieu following a heavy resistance exercise bout in women. Ethanol ingestion appeared to have no significant effect on the characteristics of acute hormonal augmentation in TT, FT, GH, COR, IGF-1, or E2. digital.library.unt.edu/ark:/67531/metadc822770/
Examination of Sexual Differences in the Acute Effects of Haloperidolon Licking
Schizophrenia is a debilitating psychiatric condition affecting almost one percent of the US population. Typical antipsychotics (e.g., haloperidol) have been in use for several decades and are generally very effective in treating the emotional and cognitive effects of schizophrenia, but are used as the last line of treatment due to their severe extrapyramidal motor side effects under chronic exposure. The present study was conducted to investigate the role of sex in determining the oromotor side effects of typical antipsychotics via measuring different behavioral dimensions of male and female Sprague-Dawley rats licking sucrose after haloperidol treatment. The results showed a stronger sensitivity in female rats than male rats within total licking responses and inter-lick intervals. The present results suggest closer attention needs to be paid to the role that sexual hormones play in the motor slowing and behavior-reducing effects of antipsychotics. digital.library.unt.edu/ark:/67531/metadc822780/
Ghost Machine
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This thesis consists of a collection of poems. By virtue of its content and arrangement, the collection ruminates on and attempts to work through the problem of corporeality and bodily experience: the anxieties surrounding illness, mortality, and the physicality of contemporary life. This collection explores the tension inherent in the mind/body duality and, rather than prescribing solutions, offers multiple avenues and perspectives through which to view bodily experience, as well as how that experience affects an individual’s identity, agency, and sense of self. digital.library.unt.edu/ark:/67531/metadc822764/
Guidelines for Greening (Renovation) of Existing Homes
This Thesis is aimed at evaluating the options of renovation for an existing residential building to make it more energy efficient. The various aspects in the basic structures of residential homes are discussed in order to help the user identify the areas of the house for which renovation is required to improve the energy efficiency of the building. These aspects include doors, roof and wall in addition to various systems of electrical wiring, mechanical systems of ventilation, heating and cooling and plumbing systems for the efficient flow of water throughout the house. The renovation options have been described in detail to provide as many possibilities to the user as possible. The building taken for renovation is a 1953 suburban home which has been awarded the honor of being the first building to be labeled as Zero Energy Home in its vicinity. This has made the home so efficient that its expenditure of energy has become equivalent to its energy generation, therefore, cancelling each other out and creating an estimate of zero energy. digital.library.unt.edu/ark:/67531/metadc822735/
A High-fat Meal Alters Post-prandial Mrna Expression of Sirt1, Sirt4, and Sirt6
Sirtuins (SIRT) regulate the transcription of various genes involved in the development of diet-induced obesity and chronic disease; however, it is unknown how they change acutely following a high-fat meal. The purpose of this study was to determine the effect of a high-fat meal (65% kcals/d; 85% fat recommendation), on SIRT1-7 mRNA expression in blood leukocytes at 1, 3, and 5-h post-prandial. Men and women (N=24) reported to the lab following an overnight fast (>12H). Total RNA was isolated and reverse transcribed prior to using a Taqman qPCR technique with 18S rRNA as a normalizer to determine SIRT1-7 mRNA expression. An additional aliquot of serum was used to measure triglycerides. Data was analyzed using a RM ANOVA with P<0.05. Triglycerides (P<0.001; 124%) peaked at 3-h. SIRT 1 (P=0.004; 70%), and SIRT 6 (P=0.017; 53%) decreased expression at 3-h. SIRT4 (P=0.024) peaked at 5H relative to baseline (70%) and 3-h (68%). To our knowledge, this is the first study to report that consumption of a high-fat meal transiently alters SIRT mRNA expression consistent in a pattern that mirrors changes in serum triglycerides. Decrease in expression of SIRT1 and SIRT6 combined with an increased SIRT4 would be consistent with an increase in metabolic disease risk if maintained on a chronic basis. digital.library.unt.edu/ark:/67531/metadc822825/
Impact of Green Design and Technology on Building Environment
Currently, the public has a strong sense of the need for environment protection and the use of sustainable, or “green,” design in buildings and other civil structures. Since green design elements and technologies are different from traditional design, they probably have impacts on the building environment, such as vibration, lighting, noise, temperature, relative humidity, and overall comfort. Determining these impacts of green design on building environments is the primary objective of this study. The Zero Energy Research (ZOE) laboratory, located at the University of North Texas Discovery Park, is analyzed as a case study. Because the ZOE lab is a building that combines various green design elements and energy efficient technologies, such as solar panels, a geothermal heating system, and wind turbines, it provides an ideal case to study. Through field measurements and a questionnaire survey of regular occupants of the ZOE lab, this thesis analyzed and reported: 1) whether green design elements changed the building’s ability to meet common building environmental standards, 2) whether green design elements assisted in Leadership in Energy and Environmental Design (LEED) scoring, and 3) whether green design elements decreased the subjective comfort level of the occupants. digital.library.unt.edu/ark:/67531/metadc822831/
Indigenous Knowledge on the Marshall Islands: a Case for Recognition Justice
Recent decades have marked growing academic and scientific attention to the role of indigenous knowledge in climate change adaptation, mitigation, and detection strategies. However, how indigenous knowledge is incorporated is a point of contention between self-identifying indigenous groups and existing institutions which combat climate change. In this thesis, I argue that the full inclusion of indigenous knowledge is deterred by certain aspects of modernity. In order to overcome the problems of modernity, I argue that a recognition theory of justice is needed as it regards to indigenous knowledge. Recognition justice calls for indigenous groups to retain meaningful control over how and when their indigenous knowledge is shared. To supplement this, I use the Marshall Islands as a case study. The Marshall Islands afford a nice particular case because of their longstanding colonial relationship with the United States and the impending danger they face of rising sea levels. Despite this danger, the Republic of the Marshall Islands calls for increased recognition as leaders in addressing climate change. digital.library.unt.edu/ark:/67531/metadc822739/
The Influence of Local Forage Variability on White-tailed Deer (Odocoileus Virginianus) Body Size at Fort Hood, Texas
Nutritional quality and availability is thought to regulate geographic patterns of variability in animal body size due to phenotypic plasticity. The purpose of this study is to determine how vegetation quality, abundance and population density influence white-tailed deer (Odocoileus virginianus) body size on a subregional spatial scale at Fort Hood, Texas. Harvest and census records are used to test the hypothesis that white-tailed deer exhibit phenotypic plasticity (e.g. larger body size) in response to differences in vegetation quality and availability. Results from these analyses suggest that forage quality and abundance alone is not a main driver of white-tailed deer body size. Analysis of deer population density (generally) resulted in an inverse relationship with body size. Areas with high quality forage and low population density support larger deer while areas with low quality forage and high density support smaller than average deer. The few exceptions occur in areas exhibiting poor quality forage and low population density or high forage quality and high density. Results from this study suggest that continued overcrowding of deer within isolated areas may eventually lead to efficiency phenotypic conditions producing smaller sized deer. These results could prove useful in interpreting deer population responses to harvest management. For successful local management of deer, studies examining the combined influence of habitat variables (such as forage quality, abundance and population density) on deer health offer managers valuable information needed to establish annual harvest goals and understand deer-habitat relationships relative to carrying capacity. digital.library.unt.edu/ark:/67531/metadc822844/
Influence of the Choice of Disease Mapping Method on Population Characteristics in Areas of High Disease Burdens
Disease maps are powerful tools for depicting spatial variations in disease risk and its underlying drivers.  However, producing effective disease maps requires careful consideration of the statistical and spatial properties of the disease data. In fact, the choice of mapping method influences the resulting spatial pattern of the disease, as well as the understanding of its underlying population characteristics. New developments in mapping methods and software in addition to continuing improvements in data quality and quantity are requiring map-makers to make a multitude of decisions before a map of disease burdens can be created. The impact of such decisions on a map, including the choice of appropriate mapping method, not been addressed adequately in the literature. This research demonstrates how choice of mapping method and associated parameters influence the spatial pattern of disease. We use four different disease-mapping methods – unsmoothed choropleth maps, smoothed choropleth maps produced using the headbanging method, smoothed kernel density maps, and smoothed choropleth maps produced using spatial empirical Bayes methods and 5-years of zip code level HIV incidence (2007- 2011) data from Dallas and Tarrant Counties, Texas. For each map, the leading population characteristics and their relative importance with regards to HIV incidence is identified using a regression analysis of a CDC recommended list of socioeconomic determinants of HIV. Our results show that the choice of mapping method leads to different conclusions regarding the associations between HIV disease burden and the underlying demographic and socioeconomic characteristics. Thus, the choice of mapping method influences the patterns of disease we see or fail to see. Accurate depiction of areas of high disease burden is important for developing and targeting appropriate public health interventions. digital.library.unt.edu/ark:/67531/metadc822816/
An Initial Study of Binary and Ternary Ti-based Alloys Manufactured Using Laser Engineered Net Shaping (Lenstm)
In this study an initial assessment of the composition – microstructure – property relationships in binary and ternary Ti – based systems are made possible using LENSTM technology. Laser Engineering Net Shaping (LENSTM), a rapid prototyping, directed laser deposition methodology of additive manufacturing (AM) was used to create bulk homogenous specimens that are compositionally graded. Compositionally graded specimens were made possible by incorporating elemental blends of powder during the LENSTM process. While there have been numerous studies assessing the influence of common elements (e.g., V, Mo, Al, and Cr) on the resulting microstructure in titanium alloys, other elements have been neglected. A systematic study of the Ti – Fe – Al ternary system based upon varying compositions of the eutectoid former, Fe with Al to stabilize the a and b phases respectively has also been neglected. This research effort focuses on exploiting the LENSTM process by rapidly assessing the composition – microstructure – property relationships in a combinatorial approach for the Ti – W, Ti – Fe, and Ti – Fe – Al systems. Compositionally graded specimens of Ti – xW (0<x<40wt.%(14.79at.%)), Ti – xFe (0<x<35wt.%(36.37at.%)), and Ti – xFe – yAl (0<x<40wt.%(36.37at.%)), y=5,10, 15wt.%) have been heat treated to also assess the influence of thermal history on microstructural features such as phase composition and volume fraction. Lastly, a Ti – xMo (0<x<40wt.%(24.96at.%)) compositionally graded specimen was deposited to re-assess the Mo-equivalency nature of W, as well as assess the role of phase separation in microstructural evolution at temperatures above and below the invariant point (~695°C) of the Ti – W binary system. digital.library.unt.edu/ark:/67531/metadc822823/
Let Her Be Shorn: 1 Corinthians 11 and Female Head Shaving in Antiquity
In 1 Corinthians 11:3-15, Paul writes that if a woman is to be so immodest as to wear her hair uncovered while praying or prophesying in a Christian assembly she might as well shave her head. Paul instructs the Corinthians that it is “one and the same” for a woman to have her head shaved and for her to unveil her hair. There is a large body of works cataloging the modesty standards in Hellenistic Greece but Paul’s reference to head-shaving remains obscure. This thesis looks to find the best explanation of Paul’s instructions. Research in this topic began as an investigation of a popular modern view. It can be found in conversation or a simple Google search, that women in Ancient Greece with their head shaved were prostitutes. Beyond being prostitutes, they were probably temple prostitutes. The evidence does not bear this out as there is no artwork depicting prostitutes, or indeed any women, with their heads shaved. Instead prostitutes are shown in Greek erotic art with both long and short hair, some with and some without head coverings. Literary sources do offer several different examples of women who had their hair cut off. There are examples of women shaving their hair off in Lucian’s The Syrian Goddess, Tacitus’ Germania, Plutarch’s Lycurgus and Roman Questions, several Talmudic sources, and On Fortune II, formerly attributed to Dio Chrysostom. By examining these sources in tandem with 1 Corinthians 11, the most probable impetus behind Paul’s writing relates to punishments for adultery. digital.library.unt.edu/ark:/67531/metadc822830/
Lone Star Insanity: Efforts to Treat the Mentally Ill in Texas, 1861-1929
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During the mid-nineteenth century, the citizens of Texas were forced to keep their mentally disturbed family members at home which caused stress on the caregivers and the further debilitation of the afflicted. To remedy this situation, mental health experts and Texas politicians began to create a system of healing known as state asylums. The purpose of this study is to determine how Texas mental health care came into being, the research and theories behind the prevention and treatment programs that asylum physicians employed to overcome mental illness, in addition to the victories and shortcomings of the system. Through this work, it will be shown that during the 1850s until the 1920s institutions faced difficulty in achieving success from many adverse conditions including, but not limited to, overcrowding, large geographical conditions, poor health practices, faulty construction, insufficient funding, ineffective prevention and treatment methods, disorganization, cases of patient abuse, incompetent employees, prejudice, and legal improprieties. As a result, by 1930, these asylums were merely places to detain the mentally ill in order to rid them from society. This thesis will also confirm that while both Texas politicians and mental health experts desired to address and overcome mental illness in Texas, they were unable to do so due to arguments, selfishness, corruption, failures, and inaction on the part of both sides. However, this thesis will ultimately reveal it was lack of full support from Texas legislators, deriving from the idea that this system was not one of their top priorities among the state’s concerns, that led to the inability of the Texas mental health care system to properly assist their patients. digital.library.unt.edu/ark:/67531/metadc822840/
Longitudinal Prevalence of Disordered Eating and Weight Control Behaviors in Female Collegiate Athletes
Female collegiate athletes have been established as a high-risk group for the development of eating disorders due to the high prevalence rates of clinical and subclinical eating disorders, which have ranged from 1.9% to 16.6% and 4.0% to 26.1%, respectively. Collegiate athletes appear to meet criteria for ED-NOS more often than anorexia or bulimia nervosa, and frequently engage in pathogenic weight control behaviors (e.g., dieting, excessive exercise). To date, only a few studies have examined the long-term stability of eating disorders in collegiate female athletes. The current study investigated the prevalence of eating disorders (i.e., eating disordered, symptomatic, and asymptomatic) and pathogenic weight control behaviors (e.g, binging, vomiting, laxative use) in 325 NCAA-DI female collegiate gymnasts and swimmers/divers across two time points – the beginning of their competitive seasons (Time 1) and during the final two weeks of their competitive seasons (Time 2). By Time 2, 90% of the athletes classified as eating disordered at Time 1 (n = 20) maintained clinical or subclinical eating disturbances. Of the 83 athletes originally symptomatic, 37.3% remained so and 10.8% became eating disordered. Significantly more athletes became satisfied with their bodies over the course of the season than became dissatisfied. The athletes reported using exercise and dieting/fasting as the most frequent forms of weight control behaviors, each of which were used less frequently at Time 2 than at Time 1. The results support overall stability of eating disorder behaviors and classification over the course of a competitive season. Limitations and implications are discussed. digital.library.unt.edu/ark:/67531/metadc822790/
Migration Information Gathering by Mexican-origin Immigrants in the Pre-migration Phase
U.S. immigration procedures are complex and may elude the average individual seeking admission to the United States. Understanding this, the current study investigates how information resources are used by potential migrants to learn about the migratory process. Using a mixed-methods approach, I interviewed 30 Mexican immigrants with unauthorized immigration experience about the process of gathering migration information in the pre-migration phase. Qualitative data were coded using seven themes generated from the primary research questions, including: Information Resources, Resources Used During Migration, Motivation for Migration, Method of Migration, Lack of Information/Misinformation, Types of Help and Types of Information. Findings suggest that the factors motivating migrants to come to the U.S. are combined in complex ways and lack of information about legal alternatives to unauthorized migration is an important factor influencing method of migration. Also, while access to new information resources is increasing, these resources are not being tapped for migration information. digital.library.unt.edu/ark:/67531/metadc822813/
Mineola
Mineola is a poetic, observational, immersive documentary centered in the town of Mineola, Texas. The film provides an intimate, first person perspective of different locations in the town as well as underlying subversive beliefs and traditions. The film’s authoritative perspective guides the viewer not only in a direction of observation but personal connection to nostalgia of small communities. digital.library.unt.edu/ark:/67531/metadc822789/
The Musical Language of Alberto Ginastera’s Panambí and the Influence of Claude Debussy’s La Mer and Igor Stravinsky’s Le Sacre Du Printemps
Alberto Ginastera completed his ballet Panambí in 1937. The ballet was arranged as a symphonic suite, and was performed the same year at the Teatro Colon in Buenos Aires, conducted by Juan José Castro. Panambí marked the beginning of Alberto Ginastera’s long and successful career as an Argentine composer. Chapter I of this document provides a brief introduction into the history behind Alberto Ginastera’s Panambí suite, and includes a review of the research that is exclusively devoted to the suite, as well as documents that do not provide direct analyses of Panambí, but contain information that aid in a better understanding of the suite’s composition. Chapter II includes analyses of the suite that illustrate important elements that contribute to the structure and sound of the Panambí suite. These components include Ginastera’s construction of the La Noche theme found in the first movement and its use as a master set, his use of diatonic collections and pitch centricity, the importance of unordered pitch class intervals IC1 and IC6, his use of aggregate completion as a compositional method, and his use of local motives over larger spans of temporal space. Chapter III explores the possibility that many of these compositional methods are due to the influence of Claude Debussy’s La Mer and Igor Stravinsky’s Le Sacre du Printmeps. The “guitar chord” may also be the result of the influence of Debussy’s La Mer. digital.library.unt.edu/ark:/67531/metadc822749/
“No Paper Cowboys”: Stories
Equilibrium is paramount in the crafting of a story, and for every writer this sense of balance is different. The writer must manage a balance of showing and telling, of denotation and connotation, and forever strive to find the perfect word in both the denotative and connotative sense, so that the reader and writer can meeting in a living story—both in the ink on the page and the remaining white space. digital.library.unt.edu/ark:/67531/metadc822819/
No Quarter: the Story of the New Orleans Greys
The purpose of this thesis document is to explain the process of making the documentary film, No Quarter: The Story of the New Orleans Greys. The document is organized by having the prospectus and the film proposal at the beginning, with the body describing how the film was made based on the prospectus. The purpose of the film is to tell the history of a unit of volunteers in the Texas Revolution, the New Orleans Greys. The document describes the methods used to make the film and how it will be distributed to the intended audience. As the thesis explains, the film changed slightly from the prospectus, however the resulting film was successful in telling the history of the little-known New Orleans Greys. digital.library.unt.edu/ark:/67531/metadc822740/
Parameter Estimation of Microwave Filters
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The focus of this thesis is on developing theories and techniques to extract lossy microwave filter parameters from data. In the literature, the Cauchy methods have been used to extract filters’ characteristic polynomials from measured scattering parameters. These methods are described and some examples are constructed to test their performance. The results suggest that the Cauchy method does not work well when the Q factors representing the loss of filters are not even. Based on some prototype filters and the relationship between Q factors and the loss, we conduct preliminary studies on alternative representations of the characteristic polynomials. The parameters in these new models are extracted using the Levenberg–Marquardt algorithm to accurately estimate characteristic polynomials and the loss information. digital.library.unt.edu/ark:/67531/metadc822826/
Phenotypic Morphological Plasticity Induced by Environmental Salt Stress in the Brine Shrimp, Artemia Franciscana
Phenotypic plasticity is the ability of an organism to express different phenotypes in response to biotic or abiotic environmental cues. The ability of an organism to make changes during development to adjust to changes in its environment is a key to survival. Sexually reproducing organisms that have short life cycles and that are easy to raise in the laboratory are more conducive for developmental phenotypic plasticity. Considerable research has already been carried out on the brine shrimp, Artemia franciscana, regarding its morphology due to changing salinities. There is, however, little research considering subsequent generations and how there morphology might be affected by parental experiences. This study has examined: 1) the morphological effects of different rearing regimes of different salinity levels, and 2) the epigenetic transgenerational transfer of these morphological traits in A. franciscana. Measurements included rate of growth (as measured by instar), body size, body length, and other morphological traits. A gradual increase to more hyperosmotic conditions during development produced brine shrimp that were larger in size and also more developmentally advanced. Salinity stress experienced by adults had increased the growth rate in the F1 offspring of A. franciscana. Collectively, these data indicate that Artemia franciscana is a tractable model for investigating phenotypic plasticity. These findings have added to the ever-growing field of developmental phenotypic plasticity while also providing more information on the natural history and adaptive abilities of A. franciscana. digital.library.unt.edu/ark:/67531/metadc822750/
Photoinduced Toxicity in Early Lifestage Fiddler Crab (Uca Longisignalis) Following Exposure to Deepwater Horizon Spill Oil
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The 2010 Deepwater Horizon (DWH) oil spill resulted in a large release of polycyclic aromatic hydrocarbons (PAH) into the Gulf of Mexico. PAH can interact with ultraviolet radiation (UV) resulting in increased toxicity, particularly to early lifestage organisms. The goal of this research was to determine the sensitivity of fiddler crab larvae (Uca longisignalis) to photo-induced toxicity following exposure to Deepwater Horizon spill oil in support of the DWH Natural Resource Damage Assessment. Five replicate dishes each containing 20 larvae, were exposed to one of three UV treatments (10%, 50%, and 100% ambient natural sunlight) and one of five dilutions of water accommodated fractions of two naturally weathered source oils. A dose dependent effect of PAH and UV on larval mortality was observed. Mortality was markedly higher in PAH treatments that included co-exposure to more intense UV light. PAH treatments under low intensity sunlight had relatively high survival. These data demonstrate the importance of considering combined effects of non-chemical (i.e. UV exposure) and chemical stressors and the potential for photo-induced effects after exposure to PAH following the Deepwater Horizon spill. digital.library.unt.edu/ark:/67531/metadc822799/
Preliminary Analysis of an Innovative Rotary Displacer Stirling Engine
Stirling engines are an external combustion heat engine that converts thermal energy into mechanical work that a closed cycle is run by cyclic compression and expansion of a work fluid (commonly air or Helium) in which, the working fluid interacts with a heat source and a heat sink and produces network. The engine is based on the Stirling cycle which is a subset of the Carnot cycle. The Stirling cycle has recently been receiving renewed interest due to some of its key inherent advantages. In particular, the ability to operate with any form of heat source (including external combustion, flue gases, alternative (biomass, solar, geothermal) energy) provides Stirling engines a great flexibility and potential benefits since it is convinced as engines running with external heat sources. However, several aspects of traditional Stirling engine configurations (namely, the Alpha, Beta, and Gamma), specifically complexity of design, high cost, and relatively low power to size and power to volume ratios, limited their widespread applications to date. This study focuses on an innovative Stirling engine configuration that features a rotary displacer (as opposed to common reciprocating displacers), and aims to utilize analytical and numerical analysis to gain insights on its operation parameters. The results are expected to provide useful design guidelines towards optimization. The present study starts with an overview of the Stirling cycle and Stirling engines including both traditional and innovative rotary displacer configurations, and their major advantages and disadvantages. The first approach considers an ideal analytical model and implements the well-known Schmidt analysis assumptions for the rotary displacer Stirling engine to define the effects of major design and operation parameters on the performance. The analytical model resulted in identifying major variables that could affect the engine performance (such as the dead volume spaces, temperature ratios and the leading phase angle). It was shown that the dead volume could have a drastic effect over the engine performance and the optimum phase angle of the engine is 90o. The second approach considers a non-ideal analytical model and aims to identify and account the main sources of energy losses in the cycle to better represent the engine performance. The study showed that the ideal efficiency and the non-ideal efficiency could have 15% difference that could have as an enormous effect on the engine performance. digital.library.unt.edu/ark:/67531/metadc822801/
Prison Notes: an Introductory Study of Inmate Marginalia
This thesis introduces the study of inmate marginalia as a method for understanding inmates’ uses of texts in prison libraries and for understanding the motivations for these uses. Marginalia are the notes, drawings, underlining, and other markings left by readers in the texts with which they interact. I use the examples of the Talmudic projects to set a precedent for the integration of marginal discourses into the central discourse of society. Next, I discuss the arguments surrounding the use of texts in prison libraries, including an outline for an ideal study of inmate marginalia. Finally, I discuss the findings of my on-site research at four prison libraries in Washington State. After scanning evidence of marginalia from forty-eight texts, a relatively small sample, I divided the marginalia by gender of facility, genre of text, address of the marginalia, and type of marginalia and found statistically significant correlations (p < 0.05) between gender and genre, gender and address, gender and type, and genre and type. However, while these correlations are statistically weak and require further investigation, the statistically significant correlations indicate the potential for integrating inmate marginalia studies into the scholarly discussions regarding inmates’ interactions with texts in prison. digital.library.unt.edu/ark:/67531/metadc822765/
Relationship Centrality and Expressive Writing: Understanding Post-breakup Distress
When a romantic relationship ends in dissolution, the ex-partners may experience distress similar to post-traumatic stress or complex grief (i.e., dysphoric mood, feelings of loss, intrusive memories, negative rumination regarding the relationship, and a loss of self-esteem). Interventions designed to reduce post-breakup distress have historically attempted to foster integration of the breakup into the self-narrative through techniques such as expressive writing. Recent research indicates centrality, or heightened integration of an event or concept into an individual’s identity, predicts heightened levels of distress in the case of negative life events, including romantic relationship dissolution. Given the role romantic relationships themselves play in identity formation, exploration is warranted of the potential distress resulting from over-identification with a romantic relationship itself, or relationship centrality, after a breakup has occurred. Furthermore, if an individual has overly-integrated a relationship into their identity, the effectiveness of interventions focusing on further integration of the breakup is called into question. This study explored the centrality of participants’ previous romantic relationships, the distress resulting from the dissolution of those relationships, and the role of expressive writing as a distress reduction tool when centrality is taken into account. digital.library.unt.edu/ark:/67531/metadc822743/
The Role of Crystallographic Texture in Achieving Low Friction Zinc Oxide Nanolaminate Films
Metal oxide nanolaminate films are potential high temperature solid lubricants due to their ability to exhibit significant plasticity when grain size is reduced to the nanometer scale, and defective growth structure is achieved by condensation of oxygen vacancies to form intrinsic stacking faults. This is in contrast to conventional microcrystalline and single crystal oxides that exhibit brittle fracture during loading in a sliding contact. This study emphasizes the additional effect of growth orientation, in particular crystallographic texture, on determining the sliding friction behavior in nanocolumnar grain zinc oxide films grown by atomic layer deposition. It was determined that zinc oxide low (0002) versus higher (101 ̅3) surface energy crystallographic planes influenced the sliding friction coefficient. Texturing of the (0002) grains resulted in a decreased adhesive component of friction thereby lowering the sliding friction coefficient to ~0.25, while the friction coefficient doubled to ~0.5 with increasing contribution of surface (101 ̅3) grains. In addition, the variation of the x-ray grazing incident angle from 0.5° to 5° was studied to better understand the surface grain orientation as a function of ZnO layer thickness in one versus four bilayer nanolaminates where the under layer (seed layer) was load-bearing Zn(Ti,Zr)O3. digital.library.unt.edu/ark:/67531/metadc822792/
The Role of Cysteinyl Leukotriene Receptor 2 in Thrombocyte Aggregation
Cysteinyl leukotriene receptor 2, a G-protein coupled receptor known to be expressed and functional on human platelets. However, it seems that upon ligand activation the cysteinyl leukotriene receptor 2 activates a variety of signaling pathways in multiple cell types among different species. Previously, a former laboratory member Vrinda Kulkarni found cysteinyl leukotriene receptor 2 to be expressed on the surface of adult zebrafish thrombocytes. In this work I studied the characteristics of aggregation in adult zebrafish thrombocytes with the knockdown of cysteinyl leukotriene receptor 2. I used a newly developed knockdown method to study the function of cysteinyl leukotriene receptor 2. Knockdown of the cysteinyl leukotriene was confirmed using RT-PCR results showed p=.001, reduced sell surface level of expression of the cysteinyl leukotriene receptor 2 results showed that p=.002. I found that the knockdown of cysteinyl leukotriene receptor 2 results in prothrombotic thrombocytes by using flow cytometry p=.0001. digital.library.unt.edu/ark:/67531/metadc822817/
The Role of Family in Alcohol Consumption Among Turkish Adolescents
Alcohol consumption among adolescents is an important issue because of its link to many negative social and health problems, including depression, suicide, and aggression. Drawing from Hirschi’s social bonding theory and Agnew’s general strain theory, this study examines the effects of family relations on alcohol consumption among Turkish adolescents. Social bonding theory suggests that individuals with stronger social bonds are less likely to use alcohol than individuals with weaker social bonds. General strain theory, on the other hand, proposes that individuals with higher levels of strain due to financial difficulties and/or negative relationships are more likely to consume alcohol compared to individuals with lower levels of strain. In particular, this study proposes to examine how parental attachment, parental monitoring, time spent with family, parents’ religiosity, family economic strain, and negative life events in the family predict alcohol consumption among adolescents in Turkey. 2008 Youth in Europe (YIE) project data is used in the study. In general, the results indicate that social bonding and strain factors have significant effects on the adolescents’ alcohol consumption patterns. These findings will help to inform prevention programs aimed at reducing adolescent alcohol risk behaviors by explaining the importance of family relationships. digital.library.unt.edu/ark:/67531/metadc822734/
Role of Gpr17 in Thrombocyte Aggregation in Adult Zebrafish
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GPR17, a uracil nucleotide cysteinyl leukotriene receptor, belongs to the GPCR (G protein coupled receptor) family. It has been shown recently that inhibiting this protein in the nervous system in mice can lead to blockage of oligodendrocyte maturation, which supports myelin repair. Interestingly, our laboratory found GPR17 in thrombocytes. However, we do not know whether it has any function in thrombocyte aggregation or the nature of the ligand. In this paper, we studied the role of GPR17 in hemostasis, which is a fundamental defense mechanism in the event of injury. Using zebrafish as a model system, our laboratory has studied specifically thrombocytes, which play a significant role in hemostasis. The major reasons to use zebrafish as a model system are that their thrombocytes are functionally equivalent to human platelets, the adult fish are amenable to knockdown experiments, and they are readily available in the market. This study was performed by using a piggy back knockdown method where we used a chemical hybrid of control morpholino and an antisense oligonucleotide sequence leads to the degradation the mRNA for GPR17. After knockdown GPR17 in thrombocytes, the percent difference of the thrombocytes aggregation between the control and knockdown blood samples was measured by flow cytometry. We used various thrombocyte agonists to study differences in aggregation between the control and knockdown blood samples. The study showed that knockdown of GPR17 resulted in no significant differences in percent thrombocyte aggregation between control and agonist treated samples except for a slight increase in collagen-treated samples. Thus, it appears that GPR17 has no significant role in hemostasis. digital.library.unt.edu/ark:/67531/metadc822797/
Searching for a Savior
This collection of essays includes a preference that investigates the role and importance of setting and character in a nonfiction narrative. The preface assesses the writings of four great authors, examining how each author use setting and characterization to further the purpose of their story. This collection focuses on four different issues that the author has wrestled with for two decades. While “Desperado” is an investigation into the problems within her own family, “Being Black Me” highlights the authors struggle against the racial inequality her hometown. “Voices In The Dark”, the author analyze how the abuse she suffered as a child has influenced her life and contributed to a drinking problem that is explored in a later essay “Alors On Danse”. digital.library.unt.edu/ark:/67531/metadc822805/
Self-definition and College Adaptation in Students From the Ronald E Mcnair Postbaccalaureate Achievement Program
While a great deal of psychological research is conducted on college students, less has been done on their adaptation to college. These young adults, as they develop ego identity and differentiate themselves from parents and families, must adjust to the social and academic environment of college. Psychosocial adjustment predicts college retention better than academic predictors do. First generation college students face greater than typical challenges adapting to college. The Ronald E. McNair Post-Baccalaureate Achievement Program exists to aid first generation, lower income undergraduate student who wish to pursue a doctoral degree. Self-definition scored from thematic apperceptive technique stories reflects an individual’s relative freedom from social role constraint. This study examined the role of self-definition and familial understanding and acceptance in this population as predictors of successful adaptation to college. While neither was found to be a significant predictor, family understanding and acceptance was found to be a more defining characteristic of this sample than was self-definition. This suggests that when social support is sufficient, individuals do not need to rely on self-definition. digital.library.unt.edu/ark:/67531/metadc822821/
Shame Due to Heterosexism, Self-esteem and Perceived Stress: Correlates of Psychological Quality of Life in a Lesbian, Gay and Bisexual Sample
Sexual minorities experience higher levels of stress than heterosexuals, which in turn affects coping and psychological quality of life (PQOL). Although many sexual minorities remain mentally healthy, a higher prevalence of mental disorders among members of the lesbian, gay and bisexual (LGB) communities exists; thus, LGB PQOL becomes an important area to examine. Several key factors are related to PQOL: shame due to heterosexism, self-esteem and perceived stress. Using minority stress model, I hypothesized that shame due to heterosexism and perceived stress are negatively correlated with PQOL, while self-esteem is positively correlated with PQOL. I hypothesized that collectively shame due to heterosexism, self-esteem and perceived stress account for a significant proportion of the variance in PQOL, that self-esteem moderates the relationship between perceived stress and PQOL and that age moderates the relationship between shame due to heterosexism and PQOL. I calculated Pearson product-moment correlation coefficient and found shame due to heterosexism was negatively correlated with PQOL (r(146) = -.21, p = .009), perceived stress was negatively correlated with PQOL (r (146) = -.69, p < .001) and self-esteem was positively correlated with PQOL (r(146) = .72, p < .001). I conducted a regression analysis and found our model accounted for 59% of the variance in PQOL (adj. R2 = .59, F(3, 144) = 68.88, p < .001). Self-esteem did moderate the relationship between perceived stress and PQOL (p = .029), but age did not moderate the relationship between shame due to heterosexism and PQOL. Results suggest perceived stress and self-esteem play key roles in sexual minorities’ PQOL. Implications are discussed. digital.library.unt.edu/ark:/67531/metadc822796/
Small Town Retail Change in East Texas: an Analysis of Retail Growth, Decline, and Spatial Reconfiguration
In recent years, small towns have experienced declining levels of retail activity attributable to a variety of factors. Previously conducted research identifies a number of these factors such as changing population dynamics, continuously evolving retail practices, locational factors, and an assortment of other macroeconomic factors. Although retail decline is common for many small towns, there are some small towns that have been able to maintain their viability in an ever-changing economic climate. The primary purpose of this research is to better understand what spatial and socio-economic characteristics contribute to retail growth and decline in a series of small towns. This research highlights a selection of small towns across a 14 county area within east Texas. The selection of small towns includes a number of towns with an increasing number of retail establishments as well as a number of towns with decreasing retail establishments over the 14 year study timeframe. Contained within this research is a discussion of small town economic and retail development, as well as findings regarding spatial and socio-economic characteristics as they relate to retail growth and decline in small towns. This research finds that locational characteristics do have an effect on retail growth and decline. The research also supports the literature, which states retail growth and decline is more pronounced within certain retail categories. digital.library.unt.edu/ark:/67531/metadc822776/
Spray Cooling with Hfc-134a and Hfo-1234yf for Thermal Management of Automotive Power Electronics
This study aims to experimentally investigate the spray cooling characteristics for active two-phase cooling of automotive power electronics. Tests are conducted on a small-scale, closed loop spray cooling system featuring a pressure atomized spray nozzle. Two types of refrigerants, HFC-134a (R-134a) and HFO-1234yf, are selected as the working fluids. The test section (heater), made out of oxygen-free copper, has a 1-cm2 plain, smooth surface prepared following a consistent procedure, and would serve as a baseline case. Matching size thick film resistors, attached onto the copper heaters, generate heat and simulate high heat flux power electronics devices. The tests are conducted by controlling the heat flux in increasing steps, and recording the corresponding steady-state temperatures to obtain cooling curves. The working fluid is kept at room temperature level (22oC). Performance comparisons are made based on heat transfer coefficient (HTC) and critical heat flux (CHF) values. Effects of spray characteristics and liquid flow rates on the cooling performance are investigated with the selected coolants. Three types of commercially available nozzles that generate full-cone sprays with fine droplets are utilized in the tests. Effect of liquid flow rate is evaluated varying flow rates at 2, 3, 4 ml/s. The experimental results obtained from this study provide a framework for spray cooling performance with the current and next-generation refrigerants aimed for advanced thermal management of automotive power electronics. digital.library.unt.edu/ark:/67531/metadc822762/
Texas Paranormalists
Texas Pararnormalists mixes participatory and observational styles in an effort to portray a small community of paranormal practitioners who live and work in and around North Texas. These practitioners include psychics, ghost investigators, and other enthusiasts and seekers of the spirit world. Through the documentation of their combined perspectives, Texas Paranormalists renders a portrait of a community of outsiders with a shared belief system and an unshakeable passion for reaching out into the unknown. digital.library.unt.edu/ark:/67531/metadc822843/
Thin Cr2o3 (0001) Films and Co (0001) Films Fabrication for Spintronics
The growth of Co (0001) films and Cr2O3 (0001)/Co (0001) has been investigated using surface analysis methods. Such films are of potential importance for a variety of spintronics applications. Co films were directly deposited on commercial Al2O3 (0001) substrates by magnetron sputter deposition or by molecular beam epitaxy (MBE), with thicknesses of ~1000Å or 30Å, respectively. Low Energy Electron Diffraction (LEED) shows hexagonal (1x1) pattern for expected epitaxial films grown at 800 K to ensure the hexagonally close-packed structure. X-ray photoemission spectroscopy (XPS) indicates the metallic cobalt binding energy for Co (2p3/2) peak, which is at 778.1eV. Atomic force microscopy (AFM) indicates the root mean square (rms) roughness of Co films has been dramatically reduced from 10 nm to 0.6 nm by optimization of experiment parameters, especially Ar pressure during plasma deposition. Ultrathin Cr2O3 films (10 to 25 Å) have been successfully fabricated on 1000Å Co (0001) films by MBE. LEED data indicate Cr2O3 has C6v symmetry and bifurcated spots from Co to Cr2O3 with Cr2O3 thickness less than 6 Å. XPS indicates the binding energy of Cr 2p(3/2) is at 576.6eV which is metallic oxide peak. XPS also shows the growth of Cr2O3 on Co (0001) form a thin Cobalt oxide interface, which is stable after exposure to ambient and 1000K UHV anneal. digital.library.unt.edu/ark:/67531/metadc822733/
Weigh-in Environment and Weight Intentionality and Management of Female Collegiate Athletes
Research suggests that female athletes, in particular, experience “sport-environment” pressures such as: weight, performance, and body image demands from their coaches, teammates, and judges. These influences in tandem with society’s portrayal of the thin ideal are thought to considerably increase the risk of developing disordered eating problems in this population. Although numerous studies have been conducted over the past decade on the prevalence of eating disorders and pathogenic weight control behaviors among female athletes, few have examined in detail the weight pressures that exist within the sport environment, such as whether or not (and how often) athletes are weighed by their coaches, and how athletes respond to those pressures in terms of weight management practices. In the proposed study, we will examine the weigh-in environment, weight satisfaction, weight management practices, menstrual health, and reported source of nutritional guidance. The sample includes 414 NCAA Division I female collegiate swimmers/divers and gymnasts drawn from 26 universities across the U.S. Participants anonymously completed a series of questionnaires as part of a larger study on student-athlete health and well-being. This study found that 41% of athletes were weighed, and most often by an athletic trainer in private. Despite most weigh-ins were reportedly conducted in a positive manner, the majority of the athletes who were weighed (75%) reported using at least one strategy to manage their weight prior to weigh-ins (e.g. restrict food, increase exercise). Athletes desire to lose weight, caloric intake, and menstrual cycles were not related to whether athletes were or were not weighed. The majority of athletes received qualified nutritional guidance about how to healthfully manage their weight. Overall, weighing is occurring in a more positive manner than expected; however, athletes are continuing to report using unhealthy weight management strategies at a high rate. It seems important for athletic departments to set policies regarding weighing and to continue to provide support and education to coaching and support staff regarding eating disorder identification, referral, and treatment. digital.library.unt.edu/ark:/67531/metadc822846/
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