Degree Level

A Preliminary Controller Design for Drone Carried Directional Communication System (open access)

A Preliminary Controller Design for Drone Carried Directional Communication System

In this thesis, we conduct a preliminary study on the controller design for directional antenna devices carried by drones. The goal of the control system is to ensure the best alignment between two directional antennas so as to enhance the performance of air-to-air communication between the drones. The control system at the current stage relies on the information received from GPS devices. The control system includes two loops: velocity loop and position loop to suppress wind disturbances and to assure the alignment of two directional antennae. The simulation and animation of directional antennae alignment control for two-randomly moving drones was developed using SIMULINK. To facilitate RSSI-based antenna alignment control to be conducted in the future work, a study on initial scanning techniques is also included at the end of this thesis.
Date: August 2015
Creator: AL-Emrani, Firas
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Determining the Emissivity of Roofing Samples: Asphalt, Ceramic and Coated Cedar (open access)

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 …
Date: December 2015
Creator: Adesanya, Oludamilola
Object Type: Thesis or Dissertation
System: The UNT Digital Library
“No Paper Cowboys”: Stories (open access)

“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.
Date: December 2015
Creator: Agnew, Bryn
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Determinants of Effort and Associated Cardiovascular Response to a Behavioral Restraint Challenge (open access)

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.
Date: December 2015
Creator: Agtarap, Stephanie
Object Type: Thesis or Dissertation
System: The UNT Digital Library
"Miss Kathy" (open access)

"Miss Kathy"

Miss Kathy is a documentary film that tells the story of Kathy Griffin-Grinan, a lead recovery coach for prostitution and human trafficking with the Harris County Sheriff’s Office. Her non-profit organization —We’ve Been There, Done That – works in conjunction with law-enforcement to offer the survivors of prostitution a chance at rehabilitation. With endless enthusiasm, she mentors survivors as they struggle to escape a destructive lifestyle. This film also explores the relationship between human trafficking and prostitution, while addressing issues of victimization and exploitation.
Date: May 2015
Creator: Alexander, Jeffrey, 1982-
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Genetic Analysis of Medicago truncatula Plants with a Defective MtIRE Gene (open access)

Genetic Analysis of Medicago truncatula Plants with a Defective MtIRE Gene

Leguminous plants are able to fix nitrogen by establishing a symbiotic relationship with soil dwelling bacteria, called rhizobia. The model plant Medicago truncatula forms a partnership with Sinorhizobium meliloti whereby the plant gains bioavailable nitrogen and in exchange the bacteria gains carbohydrates. This process occurs within nodules, which are structures produced on the roots of the plants within which nitrogen is fixed. M. truncatula incomplete root elongation (MtIRE) was localized to the infection zone, which is zone II of indeterminate nodules. It was shown to encode a signaling kinase so it was anticipated to play a role in nodulation. Mutants of MtIRE in the R108 background, mutagenized with the Tnt1 retrotransposon, were obtained from reverse screen, and were assessed to determine if a disrupted MtIRE gene was the cause of nitrogen fixation defective nodules. Mutant line NF1320, having a mutant phenotype, showed typical Mendelian segregation of 3:1 when backcrossed to R108. Experimental results show that MtIRE gene is not the cause of the mutant phenotype, but was linked to the causative locus. MtIRE co-segregated with the mutant phenotype 83%. Southern blot and the first version of the M. truncatula genome (version 3.5) reported a single MtIRE gene and this was …
Date: August 2015
Creator: Alexis, Naudin
Object Type: Thesis or Dissertation
System: The UNT Digital Library
An Analysis of Du cristal…à la fumée by Kaija Saariaho and Axiom Unearthed, Original Composition (open access)

An Analysis of Du cristal…à la fumée by Kaija Saariaho and Axiom Unearthed, Original Composition

Beginning in the 1970s, and aided by the advancement and an increased prevalence of computers, spectral music emerged as an important development in twentieth century music. Spectral composers, as exemplified by Gérard Grisey and Tristan Murail, took the harmonic spectra of sounds as the fundamental materials of composition. The resulting music placed an emphasis on texture and gradually evolving forms. The generation of composers immediately following the spectralists assimilated their techniques into distinct and varying styles. Finnish composer Kaija Saariaho uses spectral techniques to create an aesthetic that generates form and progression from a sound/noise axis. In her piece Du cristal…à la fumée, a number of pendulum and half-pendulum gestures build up texture and form. The accompanying original composition Axiom Unearthed employs similar pendulum gestures and uses spectral techniques to generate melody and harmony in an aesthetic divergent from traditional spectral pieces.
Date: May 2015
Creator: Allen, John Clay
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Effects of a Psychosocial Environment on College Women’s Exercise Regulations and Social Physique Anxiety (open access)

The Effects of a Psychosocial Environment on College Women’s Exercise Regulations and Social Physique Anxiety

A positive psychosocial intervention comprised of high autonomy support, task-involvement, and caring was implemented in physical activity classes to examine its effects on college women’s basic psychological needs (i.e. autonomy, competence, relatedness), exercise regulations (i.e. external, introjected, identified, integrated, intrinsic) and social physique anxiety (SPA). We hypothesized that at the end of the semester, participants in the intervention group (N = 73) would report greater need satisfaction, more self-determined regulations and less SPA than participants in the non-intervention group (N = 60). At T1 and T2, both the intervention and non-intervention participants reported “agreeing” with experiencing an autonomy supportive, task-involving, and caring environment. Furthermore, both groups at T1 and T2 reported moderate SPA. No significant group differences were found at T1. At T2, significant group differences were observed in the intervention and non-intervention groups’ report of external regulation and intrinsic regulation. The results suggests that group exercise instructors are capable of creating a positive psychosocial environment to enhance students’ intrinsic motivation.
Date: May 2015
Creator: Alvarez, Ana
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Effect of Alloy Composition, Free Volume and Glass Formability on the Corrosion Behavior of Bulk Metallic Glasses (open access)

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 …
Date: December 2015
Creator: Ayyagari, Venkata Aditya
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Preliminary Analysis of an Innovative Rotary Displacer Stirling Engine (open access)

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 …
Date: December 2015
Creator: Bagheri, Amirhossein
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Unique Channel Email System (open access)

Unique Channel Email System

Email connects 85% of the world. This paper explores the pattern of information overload encountered by majority of email users and examine what steps key email providers are taking to combat the problem. Besides fighting spam, popular email providers offer very limited tools to reduce the amount of unwanted incoming email. Rather, there has been a trend to expand storage space and aid the organization of email. Storing email is very costly and harmful to the environment. Additionally, information overload can be detrimental to productivity. We propose a simple solution that results in drastic reduction of unwanted mail, also known as graymail.
Date: August 2015
Creator: Balakchiev, Milko
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Application of Cyclic Polarization of Aluminum 3003 Used in All-Aluminum Microchannel Heat Exchangers (open access)

Application of Cyclic Polarization of Aluminum 3003 Used in All-Aluminum Microchannel Heat Exchangers

All-aluminum microchannel heat exchangers are designed to significantly reduce refrigerant charge requirements, weight, reduced brazed joints, and decreased potential for leakage by increasing reliability. Al 3003 alloy is corrosion resistant and can be formed, welded, and brazed but the issue with all-aluminum heat exchangers is localized corrosion (pitting) in corrosive environments. Currently, there is no universally accepted corrosion test that all coil manufacturers use to characterize their products. Electrochemical testing method of cyclic polarization was employed in this investigation and relevant parameters including electrolyte corrosive agent and its concentration, electrolyte pH, and applied potential scan rate was varied to find an optimal set of parameters. Results of cyclic polarization of Al 3003 in electrolytes containing various concentrations of NaCl were compared with those of the tests in Sea Water Acidified Accelerated Test (SWAAT) electrolyte and it is shown the SWAAT electrolyte (4.2% sea salt acidified to pH of 2.9) is by far stronger (in terms of corrosivity) than typical 3.5% NaCl solution used in most corrosion testing. Corrosion rates (g/m2yr) of Al 3003 measured in this investigation were comparable to those provided by ISO 9223 standard corresponding to C1 through CX categories. Duration of cyclic polarization test is much shorter …
Date: May 2015
Creator: Barnes, Javier
Object Type: Thesis or Dissertation
System: The UNT Digital Library
No Quarter: the Story of the New Orleans Greys (open access)

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.
Date: December 2015
Creator: Barnes, Travis S.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Searching for a Savior (open access)

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”.
Date: December 2015
Creator: Batch, Julia
Object Type: Thesis or Dissertation
System: The UNT Digital Library
A High-fat Meal Alters Post-prandial mRNA Expression of SIRT1, SIRT4, and SIRT6 (open access)

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 …
Date: December 2015
Creator: Best Sampson, Jill Nicole
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Through an Open Window (open access)

Through an Open Window

The poems in this collection are elegiac; celebrations of losses and failures, tributes to the daily doldrums that are at the center of human experience. They threaten to expose the uncertainty that exists and refuses to exist in our everyday lives. They explore the otherness associated with the individual and often turn to the universal formulas of music and physics to make order of the world around them. Often times the Speaker finds that the seeming chaos manifests within her already orderly life, the daily routines of work and family. Poetic magic, so to speak, weds this ordered chaos to the laws of nature and its routines, especially birds, which makes a recurrent appearance throughout the manuscript.
Date: May 2015
Creator: Bingham, Christie
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Nanohybrids Based on Solid and Foam Polyurethanes (open access)

Nanohybrids Based on Solid and Foam Polyurethanes

Polymer nanocomposites are a going part of Materials Science and Engineering. These new composite materials exhibit dimensional and thermal stability of inorganic materials and toughness and dielectric properties of polymers. Development of nanocomposites become an important approach to create high-performance composite materials. In this study silica, fly ash, silica nanotubes and carbon black particles have been added to modify polyurethane foam and thermoplastic polyurethanes. It has been found that the addition of silica can diminish the size of foam bubbles, resulting in an increased stiffness of the material, increase of the compressive strength, and greater resistance to deformation. However, the uniformity of bubbles is reduced, resulting in increased friction of the material. Fly ash added to the foam can make bubbles smaller and improve uniformity of cells. Therefore, the material stiffness and compressive strength, resistance to deformation, and has little impact on the dynamic friction of the material. Adding nanotubes make bubble size unequal, and the arrangement of the bubble uneven, resulting in decreased strength of the material, while the friction increases. After the addition of carbon black to the polyurethane foam, due to the special surface structure of the carbon black, the foam generates more bubbles during the foaming …
Date: May 2015
Creator: Bo, Chong
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Role of GPR17 in Thrombocyte Aggregation in Adult Zebrafish (open access)

Role of GPR17 in Thrombocyte Aggregation in Adult Zebrafish

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 …
Date: December 2015
Creator: Bohassan, Maruah Hejey
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Shame Due to Heterosexism, Self-esteem and Perceived Stress: Correlates of Psychological Quality of Life in a Lesbian, Gay and Bisexual Sample (open access)

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 …
Date: December 2015
Creator: Bonds, Stacy E.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Lone Star Insanity: Efforts to Treat the Mentally Ill in Texas, 1861-1929 (open access)

Lone Star Insanity: Efforts to Treat the Mentally Ill in Texas, 1861-1929

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 …
Date: December 2015
Creator: Boyd, Dalton T.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
An Assessment of Uncommon Titanium Binary Systems: Ti-Zn, Ti-Cu, and  Ti-Sb (open access)

An Assessment of Uncommon Titanium Binary Systems: Ti-Zn, Ti-Cu, and Ti-Sb

The current study focuses on phase stability and evolution in the titanium-zinc titanium-copper and titanium-antimony systems. The study utilized the Laser Engineering Net Shaping (LENS™) processing technique to deposit compositionally graded samples of three binary system in order to allow the assessment of phase stability and evolution as a function of composition and temperature the material is subjected to. Through LENS™ processing it was possible to create graded samples from Ti-xSb (up to 13wt%) and Ti-xCu (up to 16wt%). The LENS™ deposited gradient were solutionized, and step quenched to specific aging temperature, and the resulting microstructures and phase were characterized utilizing XRD, EDS, SEM, FIB and TEM. The Ti-Zn system proved incapable of being LENS™ deposited due to the low vaporization temperature of Zn; however, a novel processing approach was developed to drip liquid Zn onto Ti powder at temperatures above β transus temperature of Ti (882 ◦C) and below the vaporization temperature of Zn (907 ◦C). The product of this processing technique was characterized in a similar way as the graded LENS™ depositions. From measurements performed on Ti-Sb it seems that Sb could be a potential α stabilizer in Ti due to the presence of a mostly homogeneous α …
Date: May 2015
Creator: Brice, David
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Freeform Cursive Handwriting Recognition Using a Clustered Neural Network (open access)

Freeform Cursive Handwriting Recognition Using a Clustered Neural Network

Optical character recognition (OCR) software has advanced greatly in recent years. Machine-printed text can be scanned and converted to searchable text with word accuracy rates around 98%. Reasonably neat hand-printed text can be recognized with about 85% word accuracy. However, cursive handwriting still remains a challenge, with state-of-the-art performance still around 75%. Algorithms based on hidden Markov models have been only moderately successful, while recurrent neural networks have delivered the best results to date. This thesis explored the feasibility of using a special type of feedforward neural network to convert freeform cursive handwriting to searchable text. The hidden nodes in this network were grouped into clusters, with each cluster being trained to recognize a unique character bigram. The network was trained on writing samples that were pre-segmented and annotated. Post-processing was facilitated in part by using the network to identify overlapping bigrams that were then linked together to form words and sentences. With dictionary assisted post-processing, the network achieved word accuracy of 66.5% on a small, proprietary corpus. The contributions in this thesis are threefold: 1) the novel clustered architecture of the feed-forward neural network, 2) the development of an expanded set of observers combining image masks, modifiers, and feature …
Date: August 2015
Creator: Bristow, Kelly H.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Effect of Post-exercise Ethanol Consumption on the Acute Hormonal Response to Heavy Resistance Exercise in Women (open access)

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 …
Date: December 2015
Creator: Budnar, Ronald Gene, Jr.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Thin Cr2O3 (0001) Films and Co (0001) Films Fabrication for Spintronics (open access)

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 …
Date: December 2015
Creator: Cao, Yuan
Object Type: Thesis or Dissertation
System: The UNT Digital Library