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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/
The Forty-fifth Illinois Volunteer Infantry Regiment: the Washburne Lead Mine Regiment in the Civil War
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Of the roughly 3,500 volunteer regiments and batteries organized by the Union army during the American Civil War, only a small fraction has been studied in any scholarly depth. Among those not yet examined by historians was one that typified the western armies commanded by the two greatest Federal generals, Ulysses S. Grant and William T. Sherman. The Forty-fifth Illinois Volunteer Infantry was at Fort Donelson and Shiloh with Grant in 1862, with Grant and Sherman during the long Vicksburg campaign of 1862 and 1863, and with Sherman in the Meridian, Atlanta, Savannah, and Carolinas campaigns in the second half of the war. These Illinois men fought in several of the most important engagements in the western theater of the war and, in the spring of 1865, were present when the last important Confederate army in the east surrendered. The Forty-fifth was also well connected in western politics. Its unofficial name was the “Washburne Lead Mine Regiment,” in honor of U.S Representative Elihu B. Washburne, who used his contacts and influences to arm the regiment with the best weapons and equipment available early in the war. (The Lead Mine designation referred to the mining industry in northern Illinois.) In addition, several officers and enlisted men were personal friends and acquaintances of Ulysses Grant of Galena, Illinois, who honored the regiment for their bravery in the final attempt to break through the Confederate defenses at Vicksburg. The study of the Forty-fifth Illinois is important to the overall study of the Civil War because of the campaigns and battles the unit participated and fought in. The regiment was also one of the many Union regiments at the forefront of the Union leadership’s changing policy toward the Confederate populace and war making industry. In this role the regiment witnessed the impact of President Abraham Lincoln’s Emancipation Proclamation. Of interest then, are the members’ views on the freeing of the slaves. Also of interest are their views on the arming of the slaves into black regiments, and on the Copperhead, anti-war movement in the Union. With ample sources on the regiment, and with no formal history of the unit having been written or published, a scholarly, modern study of the Lead Mine regiment therefore seems in order, as it would provide further insight into the Civil War from the Union soldiers’ perspective and into the sacrifices the men made in order to preserve their country. digital.library.unt.edu/ark:/67531/metadc822827/
Identification of Hox Genes Controlling Thrombopoiesis in Zebrafish
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Thrombocytes are functional equivalents of mammalian platelets and also possess megakaryocyte features. It has been shown earlier that hox genes play a role in megakaryocyte development. Our earlier microarray analysis showed five hox genes, hoxa10b, hoxb2a, hoxc5a, hoxc11b and hoxd3a, were upregulated in zebrafish thrombocytes. However, there is no comprehensive study of genome wide scan of all the hox genes playing a role in megakaryopoiesis. I first measured the expression levels of each of these hox genes in young and mature thrombocytes and observed that all the above hox genes except hoxc11b were expressed equally in both populations of thrombocytes. hoxc11b was expressed only in young thrombocytes and not in mature thrombocytes. The goals of my study were to comprehensively knockdown hox genes and identify the specific hox genes involved in the development of thrombocytes in zebrafish. However, the existing vivo-morpholino knockdown technology was not capable of performing such genome-wide knockdowns. Therefore, I developed a novel cost- effective knockdown method by designing an antisense oligonucleotides against the target mRNA and piggybacking with standard control morpholino to silence the gene of interest. Also, to perform knockdowns of the hox genes and test for the number of thrombocytes, the available techniques were both cumbersome or required breeding and production of fish where thrombocytes are GFP labeled. Therefore, I established a flow cytometry based method of counting the number of thrombocytes. I used mepacrine to fluorescently label the blood cells and used the white cell fraction. Standard antisense oligonucleotide designed to the central portion of each of the target hox mRNAs, was piggybacked by a control morpholino and intravenously injected into the adult zebrafish. The thrombocyte count was measured 48 hours post injection. In this study, I found that the knockdown of hoxc11b resulted in increased number of thrombocytes and knockdown of hoxa10b, hoxb2a, hoxc5a, and hoxd3a showed reduction in the thrombocyte counts. I then screened the other 47 hox genes in the zebrafish genome using flow sorting method and found that knockdown of hoxa9a and hoxb1a also resulted in decreased thrombocyte number. Further, I used the dye DiI, which labels only young thrombocytes at specific concentrations and observed that the knockdown of hoxa10b, hoxb2a, hoxc5a, hoxd3a, hoxa9a and hoxb1a, lead to a decrease in young thrombocytes; whereas hoxc11b knockdown lead to increase in number of young thrombocytes. Using bromodeoxyuridine, I also showed that there is increase in release of young thrombocytes into peripheral circulation in hoxc11b knockdown fish which suggests that hoxc11b significantly promotes cell proliferation rather effecting apoptosis. In conclusion, I found six hox genes that are positive regulators and one hox gene is a negative regulator for thrombocyte development. digital.library.unt.edu/ark:/67531/metadc822768/
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/
Environmental Modulation of the Onset of Air-breathing of the Siamese Fighting Fish and the Blue Gourami
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This study determined the effect of hypoxia on air-breathing onset and physiological and morphological characters in larvae of the air breathing fishes Trichopodus trichopterus and Betta splendens. Larvae were exposed intermittently (12/12 h daily) to 20, 17, and 14 kPa of PO2 from 1 to 40 days post-fertilization. Survival, onset of air breathing, wet body mass, O2, Pcrit were measured every 5 dpf. Hypoxia advanced by 4 days, and delayed by 9 days, the onset of air breathing in Betta and Trichopodus, respectively. Hypoxia increased larval body length, wet mass, and labyrinth organ respiratory surface of Betta, but did not affect these factors in Trichopodus. Hypoxic exposure increased O2 by 50-100% at each day throughout larval development in Betta, but had no effect on larval Trichopodus. Hypoxia decreased Pcrit in Betta by 37%, but increased Pcrit in Trichopodus by 70%. Larval Betta reared in hypoxia showed a modified heart rate:opercular rate ratio (3:1 to 2:1), but these changes did not occur in Trichopodus. Compared to Betta, the blood of Trichopodus had a higher P50 and much smaller Bohr and Root effects. These interspecific differences are likely due to ecophysiological differences: Betta is a non- obligatory air-breather after 36 dpf with a slow lifestyle reflected in its low metabolism, while Trichopodus is an obligatory air-breather past 32 dpf with an athletic fast lifestyle and accompanying high metabolism. digital.library.unt.edu/ark:/67531/metadc822746/
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/
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/
Mobile Learning: Factors That Influence University Students’ Intention to Use Smartphones
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This study investigated the factors that influence university students’ intention to use a smartphone. The study proposed and validated a research model based on the technology acceptance model (TAM). The TAM was modified and extended with four new constructs: social norms, perceived enjoyment, perceived value and ease of access. The constructs for the instrument of the study were adapted from previous related studies which had validated the instruments. Data were collected from 110 participants via a survey. The collected data were analyzed using hierarchical multiple-regression using the statistical package for social sciences (SPSS version 22.0). The model demonstrated a good fit where six independent variables together contributed 56.2% of the variance to the outcome or prediction. The results of the analysis were used to test a set of research hypotheses and to answer research questions. The following independent variables were found to be significant in determining university students’ intention to use mobile devices: perceived usefulness, social norms, perceived enjoyment, perceived value and ease of access. The control variables gender and degree level and the independent variable ease of use were not significant predictors. The results of this study may be useful to understand which factors are more important to the students. This understanding can be utilized by the University administrators for developing policies related to mobile learning and by the IT departments for planning organizational technology services. digital.library.unt.edu/ark:/67531/metadc822806/
Montesquieu, Diversity, and the American Constitutional Debate
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It has become something of a cliché for contemporary scholars to assert that Madison turned Montesquieu on his head and thereafter give little thought to the Frenchman’s theory that republics must remain limited in territorial size. Madison did indeed present a formidable challenge to Montesquieu’s theory, but I will demonstrate in this dissertation that the authors of the Federalist Papers arrived at the extended sphere by following a theoretical pathway already cemented by the French philosopher. I will also show that Madison’s “practical sphere” ultimately concedes to Montesquieu that excessive territorial size and high levels of heterogeneity will overwhelm the citizens of a republic and enable the few to oppress the many. The importance of this dissertation is its finding that the principal mechanism devised by the Federalists for dealing with factions—the enlargement of the sphere—was crafted specifically for the purpose of moderating interests, classes, and sects within an otherwise relatively homogeneous nation. Consequently, the diverse republic that is America today may be exposed to the existential threat anticipated by Montesquieu’s theory of size—the plutocratic oppression of society by an elite class that employs the strategy of divide et impera. digital.library.unt.edu/ark:/67531/metadc822814/
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/
Fashioning Society in Eighteenth-century British Jamaica
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White women who inhabited the West Indies in the eighteenth century fascinated the metropole. In popular prints, novels, and serial publications, these women appeared to stray from “proper” British societal norms. Inhabiting a space dominated by a tropical climate and the presence of a large enslaved African population opened white women to censure. Almost from the moment of colonial encounter, they were perceived not as proper British women but as an imperial “other,” inhabiting a middle space between the ideal woman and the supposed indigenous “savage.” Furthermore, white women seemed to be lacking the sensibility prized in eighteenth-century England. However, the correspondence that survives from white women in Jamaica reveals the language of sensibility. “Creolized” in this imperial landscape, sensibility extended beyond written words to the material objects exchanged during their tenure on these sugar plantations. Although many women who lived in the Caribbean island of Jamaica might have fit the model, extant writings from Ann Brodbelt, Sarah Dwarris, Margaret and Mary Cowper, Lady Maria Nugent, and Ann Appleton Storrow, show a longing to remain connected with metropolitan society and their loved ones separated by the Atlantic. This sensibility and awareness of metropolitan material culture masked a lack of empathy towards subordinates, and opened the white women these islands to censure, particularly during the era of the British abolitionist movement. Novels and popular publications portrayed white women in the Caribbean as prone to overconsumption, but these women seem to prize items not for their inherent value. They treasured items most when they came from beloved connections. This colonial interchange forged and preserved bonds with loved ones and comforted the women in the West Indies during their residence in these sugar plantation islands. This dissertation seeks to complicate the stereotype of insensibility and overconsumption that characterized the perception of white women who inhabited the British West Indies in the long eighteenth century. digital.library.unt.edu/ark:/67531/metadc822729/
Design, Synthesis and Study of Supramolecular Donor – Acceptor Systems Mimicking Natural Photosynthesis Processes
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This dissertation investigates the chemical ingenuity into the development of various photoactive supramolecular donor – acceptor systems to produce clean and carbon free energy for the next generation. The process is inspired by the principles learned from nature’s approach where the solar energy is converted into the chemical energy through the natural photosynthesis process. Owing to the importance and complexity of natural photosynthesis process, we have designed ideal donor-acceptor systems to investigate their light energy harvesting properties. This process involves two major steps: the first step is the absorption of light energy by antenna or donor systems to promote them to an excited electronic state. The second step involves, the transfer of excitation energy to the reaction center, which triggers an electron transfer process within the system. Based on this principle, the research is focused into the development of artificial photosynthesis systems to investigate dynamics of photo induced energy and electron transfer events. The derivatives of Porphyrins, Phthalocyanines, BODIPY, and SubPhthalocyanines etc have been widely used as the primary building blocks for designing photoactive and electroactive ensembles in this area because of their excellent and unique photophysical and photochemical properties. Meanwhile, the fullerene, mainly its readily available version C60 is typicaly used as an electron acceptor component because of its unique redox potential, symmetrical shape and low reorganization energy appropriate for improved charge separation behavior. The primary research motivation of the study is to achieve fast charge separation and slow charge recombination of the system by stabilizing the radical ion pairs which are formed from photo excitation, for maximum utility of solar energy. Besides Fullerene C60, this dissertation has also investigated the potential application of carbon nanomaterials (Carbon nanotubes and graphene) as primary building blocks for the study of the artificial photosynthesis process. digital.library.unt.edu/ark:/67531/metadc822757/
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/
Electrochemical Synthesis and Applications of Layered Double Hydroxides and Derivatives
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Layered double hydroxides (LDH) are a class of anionic clay with alternating layers of positive and negative charge. A metal hydroxide layer with divalent and trivalent metals with a positive charge is complemented by an interlayer region containing anions and water with a negative charge. The anions can be exchanged under favorable conditions. Hydrotalcite (Mg6Al2(OH)16[CO3]·4H2O) and other variations are naturally occurring minerals. Synthetic LDH can be prepared as a powder or film by numerous methods. Synthetic LDH is used in electrode materials, adsorbents, nuclear waste treatment, drug delivery systems, water treatment, corrosion protection coatings, and catalysis. In this dissertation Zn-Al-NO3 derivatives of zaccagnaite (Zn4Al2(OH)12[CO3]·3H2O) are electrochemically synthesized as films and applied to sensing and corrosion resistance applications. First, Zn-Al-NO3 LDH was potentiostatically electrosynthesized on glassy carbon substrates and applied to the electrochemical detection of gallic acid and caffeic acid in aqueous solutions. The modified electrode was then applied to the detection of gallic acid in green tea samples. The focus of the work shifts to corrosion protection of stainless steel. Modified zaccagnaite films were electrodeposited onto stainless steel in multiples layers to reduce defects caused by drying of the films. The films were deposited using a step potential method. The corrosion resistance of the films in a marine environment was investigated while immersed in 3.5 wt.% NaCl environments. Next modified zaccagnaite films were potentiostatically electrodeposited onto stainless steel followed by a hydrophobization reaction with palmitic acid in order to prepare superhydrophobic (>150° contact angle) surfaces. Each parameter of the film synthesis was optimized to produce a surface with the highest possible contact angle. The fifth chapter examines the corrosion resistance of the optimized superhydrophobic film and a hydrophobic film. The hydrophobic film is prepared using the same procedure as the superhydrophobic film except for a difference in electrodeposition potential. The corrosion resistance of these films is investigated in a simulated marine environment (3.5 wt.% NaCl) for short and extended durations. The last chapter summarizes the previous chapters and suggests future directions for this work. digital.library.unt.edu/ark:/67531/metadc804917/
A Guide to Arranging Late Eighteenth and Early Nineteenth Century Harmoniemusik in an Historical Style
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The wind octet was a popular ensemble of the classical period. In 1782, the Viennese Emperor formed a wind octet which specialized in playing opera arrangements. This music was used primarily as a form of background entertainment for dinners. This guide analyzes and compares the works of several well-known arrangers from the classical period in order to demonstrate arranging styles of the time. The arrangers of the period were often the performers of these various wind octets who were writing specifically for the players in their own ensembles. The style of Mozart’s original wind music is also discussed, in contrast to the arrangements of his works made by others. This guide is intended for serve performers of today as a tool to learn the art of arranging in an historical style. Idiosyncrasies of the classical-period wind instruments are discussed, as they relate to the style of wind arranging. The role of the contemporary arranger is compared with that of the classical period, and the case is made for the need for more contemporary arrangements of classical works using period arrangers as models. digital.library.unt.edu/ark:/67531/metadc804847/
A Precise Few-nucleon Size Difference by Isotope Shift Measurements of Helium
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We perform high precision measurements of an isotope shift between the two stable isotopes of helium. We use laser excitation of the 2^3 S_1-2^3 P_0 transition at 1083 nm in a metastable beam of 3He and 4He atoms. A newly developed tunable laser frequency selector along with our previous electro-optic frequency modulation technique provides extremely reliable, adaptable, and precise frequency and intensity control. The intensity control contributes negligibly to overall experimental uncertainty by stabilizing the intensity of the required sideband and eliminating the unwanted frequencies generated during the modulation of 1083 nm laser carrier frequency. The selection technique uses a MEMS based fiber switch and several temperature stabilized narrow band (~3 GHz) fiber gratings. A fiber based optical circulator and an inline fiber amplifier provide the desired isolation and the net gain for the selected frequency. Also rapid (~2 sec.) alternating measurements of the 2^3 S_1-2^3 P_0 interval for both species of helium is achieved with a custom fiber laser for simultaneous optical pumping. A servo-controlled retro-reflected laser beam eliminates residual Doppler effects during the isotope shift measurement. An improved detection design and software control makes negligible subtle potential biases in the data collection. With these advances, combined with new internal and external consistency checks, we are able to obtain results consistent with the best previous measurements, but with substantially improved precision. Our measurement of the 2^3 S_1-2^3 P_0 isotope shift between 3He and 4He is 31 097 535.2 (5) kHz. The most recent theoretic calculation combined with this measurement yields a new determination for nuclear size differences between 3He and 4He: ∆r_c=0.292 6 (1)_exp (8)_th (52)_exp fm, with a precision of less than a part in 〖10〗^4 coming from the experimental uncertainty (first parenthesis), and a part in 〖10〗^3 coming from theory. This value is consistent with electron scattering measurement, but a factor of 10 more precise. It is inconsistent (4 sigma) with a recent isotope shift measurement on another helium transition (2^1 S_0-2^3 S_1). Comparisons with ongoing muonic helium measurements may provide clues to the origin of what is currently called the proton puzzle: electronic and muonic measurements of the proton size do not agree. In the future, the experimental improvements described here can be used for higher precision tests of atomic theory and quantum electrodynamics, as well as an important atomic physics source of the fine structure constant. digital.library.unt.edu/ark:/67531/metadc804828/
Effect of Acute Alcohol Ingestion on Resistance Exercise Induced Mtorc1 Signaling in Human Muscle
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The purpose of this project was to further elucidate the effects post-exercise alcohol ingestion. This project had many novel aspects including using a resistance exercise (RE) only exercise design and the inclusion of women. To our knowledge, we are the first to investigate the effect of post-RE alcohol ingestion in women. In the first chapter of this project, information on the prevalence of alcohol use and the importance of skeletal muscle as a dynamic and metabolic tissue was provided. In chapter two, the effects of post-RE alcohol ingestion in men and women are detailed. The major findings of this study was that although RE elicited similar mTORC1 signaling both in men and in women, alcohol ingestion appeared to only attenuate RE-induced phosphorylation of the mTORC1 signaling pathway in men. The third chapter focused on examining the effects of post-RE alcohol ingestion on acute testosterone bioavailability. The primary findings of this study was that alcohol substantially elevated serum total and free testosterone concentrations during recovery from a bout of resistance exercise. The fourth chapter detailed factors that contribute to bone density in men. The major findings of this study was that young adult male long-distance runners who participated in resistance training at least once per week had greater bone mineral density than their non-resistance trained and non-exercise trained peers. digital.library.unt.edu/ark:/67531/metadc804831/
Enhancing User Search Experience in Digital Libraries with Rotated Latent Semantic Indexing
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This study investigates a semi-automatic method for creation of topical labels representing the topical concepts in information objects. The method is called rotated latent semantic indexing (rLSI). rLSI has found application in text mining but has not been used for topical labels generation in digital libraries (DLs). The present study proposes a theoretical model and an evaluation framework which are based on the LSA theory of meaning and investigates rLSI in a DL environment. The proposed evaluation framework for rLSI topical labels is focused on human-information search behavior and satisfaction measures. The experimental systems that utilize those topical labels were built for the purposes of evaluating user satisfaction with the search process. A new instrument was developed for this study and the experiment showed high reliability of the measurement scales and confirmed the construct validity. Data was collected through the information search tasks performed by 122 participants using two experimental systems. A quantitative method of analysis, partial least squares structural equation modeling (PLS-SEM), was used to test a set of research hypotheses and to answer research questions. The results showed a not significant, indirect effect of topical label type on both guidance and satisfaction. The conclusion of the study is that topical labels generated using rLSI provide the same levels of alignment, guidance, and satisfaction with the search process as topical labels created by the professional indexers using best practices. digital.library.unt.edu/ark:/67531/metadc804881/
Organizational Competency Through Information: Business Intelligence and Analytics As a Tool for Process Dynamization
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The data produced and collected by organizations represents both challenges and opportunities for the modern firm. Business intelligence and analytics (BI&A) comprises a wide variety of information management technologies and information seeking activities designed to exploit these information resources. As a result, BI&A has been heralded as a source of improved organizational outcomes in both the academic and practitioner literature, and these technologies are among the largest continuous IT expenditures made over the last decade.Despite the interest in BI&A, there is not enough theorizing about its role in improving firm performance. Scholarly investigations of the link between BI&A and organizational benefits are scarce and primarily exploratory in nature. Further, the majority of the extant research on BI&A is techno-centric, conceptualizing BI&A primarily an organizational technical asset. This study seeks to explicate the relationship between BI&A and improved organizational outcomes by viewing this phenomenon through the lens of dynamic capabilities, a promising theoretical perspective from the strategic management discipline. In so doing, this research reframes BI&A as an organizational capability, rather than simply a technical resource. Guided by a comprehensive review of the BI&A and dynamic capabilities literature, as well as a series of semi-structured focus groups with senior-level business practitioners with BI&A experience, this study develops and tests a model of BI&A enabled firm performance. Using a snowball sample, an online survey was administered to 137 business professionals in 24 industries. The data were analyzed using partial least squares (PLS) structural equation modeling (SEM). The findings support the contention that BI&A serve as the sensing and seizing components of an organizational dynamic capability, while transformation is achieved through business process change capability. These factors influence firm financial performance through their impact on the functional performance of the firm’s business processes. Further, this study demonstrates that traditional BI&A success factors are positively associated with BI&A sensing capability. This study makes several important contributions to BI&A research. First, this study addresses a gap in the scholarly literature by establishing a theoretical framework for the role of BI&A in achieving firm performance which is grounded in an established strategic management theory. Second, by drawing on the sense-seize-transform view of dynamic capabilities, this dissertation proposes a new conceptualization of BI&A as sensing and seizing organizational capabilities. Third, this research links the use of BI&A to improved organizational outcomes through the transformation of business processes, consistent with the view that the value of IT is derived from its impact on the value generating processes of the firm. Fourth, by viewing BI&A and business process change as distinct but inter-related components of dynamic capabilities, this research clarifies the role of BI&A in the dynamization of organizational processes, providing insight into the relationship between BI&A and business agility. Finally, this dissertation shows how BI&A capabilities are related to BI&A success factors identified in prior research. digital.library.unt.edu/ark:/67531/metadc804918/
Health-related Quality of Life and Social Engagement in Assisted Living Facilities
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This research project aims to clarify the factors that impact successful aging in Assisted Living facilities (ALFs) in Denton County, Texas. We hypothesize that social disengagement decreases physical and mental components of quality of life. This exploratory research project employed standardized questionnaires to assess residents in the following domains; HRQOL, social engagement status, level of cognition, depression, and the level of functioning. This study collected data from 75 participants living in five ALFs. The average of Physical Component Scale (PCS) and Mental Component Scale (MCS) was 35.33, and 53.62 respectively. None of the participants had five or more social contacts out of facilities, and two-third of them had two or less social contacts. On average, those participants who were more socially engaged had higher score of MCS compared with disengaged counterparts. The level of physical function significantly affects social engagement, when people with more disabilities are more likely to be socially disengaged. Social engagement and depression significantly impact MCS, when depression is a mediating factor between social engagement and mental component of quality of life. Considering the expansion in aging population in the United States within the next three decades, the demand for high quality long-term care will skyrocket consequently. This study reveals that external social engagement can sustain HRQOL of residents in assisted living facilities. digital.library.unt.edu/ark:/67531/metadc804930/
The Political Philosophy of Rabelais’s Pantagruel: Reconciling Thought and Action
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Political thinkers of the Renaissance, foremost among them Niccolò Machiavelli and Desiderius Erasmus, authored works commonly referred to as “mirrors of princes.” These writings described how princes should rule, and also often recommended a certain arrangement or relationship between the intellectual class and the political powers. François Rabelais’s five books of Pantagruel also depict and recommend a new relationship between these elements of society. For Rabelais, the tenets of a philosophy that he calls Pantagruelism set the terms between philosophers and rulers. Pantagruelism, defined in Rabelais’s Quart Livre as “gaiety of spirit confected in contempt for fortuitous things,” suggest a measured attitude toward politics. Rabelais’s prince, Pantagruel, accordingly rejects the tendencies of ancient thinkers such as Diogenes the Cynic who viewed politics as futile. Yet Pantagruel also rejects the anti-theoretical disposition of modern thinkers such as Machiavelli who placed too much confidence in politics. I demonstrate how Rabelais warns against the philosophers’ entrance into public service, and how he simultaneously promotes a less selfish philosophy than that of Diogenes. I argue that Pantagruel’s correction of his friend Panurge through the consultations of experts regarding the latter’s marriage problem shows that fortune will always trouble human life and politics. I also argue that Pantagruel’s rule over the kingdom of Utopia exemplifies a Socratic form of rule—reluctant rule—which relies on a trust that necessity (embodied in the Tiers Livre in the Pantagruelion plant) and not fortune (embodied in the Tiers Livre in Panurge’s future wife) governs the world, including the political world. digital.library.unt.edu/ark:/67531/metadc804944/
Derivation: Excerpts From a Novel
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The dissertation consists of a critical preface and excerpts from the novel Derivation. The preface details how the novel Derivation explores the tension between the artist and the academy in the university, as well as the role memory plays in the construction of fictional narratives. The preface also details how narrative voice is used to expand the scope of Derivation, and ends with a discussion of masculine tropes in the novel. Derivation traces the path of a woman trying to rebuild her life in the wake of the 2008 financial crisis, returning first to her blue collar roots before pursuing a career as an academic. digital.library.unt.edu/ark:/67531/metadc804864/
Ternary Oxide Structures for High Temperature Lubrication
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In this research, a temperature dependent tribological investigation of selected ternary oxides was undertaken. Based on the promising results of previous studies on silver based ternary oxides, copper based ternary oxides were selected to conduct a comparative study since both copper and silver are located in the same group in the periodic table of the elements. Two methods were used to create ternary oxides: (i) solid chemical synthesis to create powders and (ii) sputtering to produce thin films. X-ray diffraction was used to explore the evolution of phases, chemical properties, and structural properties of the coatings before and after tribotesting. Scanning electron microscopy, Auger scanning nanoprobe spectroscopy, and X-ray photoelectron spectroscopy were used to investigate the chemical and morphological properties of these materials after sliding tests. These techniques revealed that chameleon coatings of copper ternary oxides produce a friction coefficient of 0.23 when wear tested at 430 °C. The low friction is due to the formation of copper tantalate phase and copper in the coatings. All sputtering coatings showed similar tribological properties up to 430 °C. digital.library.unt.edu/ark:/67531/metadc804963/
Bass Reeves: a History • a Novel • a Crusade, Volume 1: the Rise
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This literary/historical novel details the life of African-American Deputy US Marshal Bass Reeves between the years 1838-1862 and 1883-1884. One plotline depicts Reeves’s youth as a slave, including his service as a body servant to a Confederate cavalry officer during the Civil War. Another plotline depicts him years later, after Emancipation, at the height of his deputy career, when he has become the most feared, most successful lawman in Indian Territory, the largest federal jurisdiction in American history and the most dangerous part of the Old West. A preface explores the uniqueness of this project’s historical relevance and literary positioning as a neo-slave narrative, and addresses a few liberties that I take with the historical record. digital.library.unt.edu/ark:/67531/metadc804965/
Thin Films As a Platform for Understanding the Conversion Mechanism of Fef2 Cathodes in Lithium-ion Microbatteries
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Conversion material electrodes such as FeF2 possess the potential to deliver transformative improvements in lithium ion battery performance because they permit a reversible change of more than one Li-ion per 3d metal cation. They outperform current state of the art intercalation cathodes such as LiCoO2, which have volumetric and gravimetric energy densities that are intrinsically limited by single electron transfer. Current studies focus on composite electrodes that are formed by mixing with carbon (FeF2-C), wherein the carbon is expected to act as a binder to support the matrix and facilitate electronic conduction. These binders complicate the understanding of the electrode-electrolyte interface (SEI) passivation layer growth, of Li agglomeration, of ion and electron transport, and of the basic phase transformation processes under electrochemical cycling. This research uses thin-films as a model platform for obtaining basic understanding to the structural and chemical foundations of the phase conversion processes. Thin film cathodes are free of the binders used in nanocomposite structures and may potentially provide direct basic insight to the evolution of the SEI passivation layer, electron and ion transport, and the electrochemical behavior of true complex phases. The present work consisted of three main tasks (1) Development of optimized processes to deposit FeF2 and LiPON thin-films with the required phase purity and microstructure; (2) Understanding their electron and ion transport properties and; (3) Obtaining insight to the correlation between structure and capacity in thin-film microbatteries with FeF2 thin-film cathode and LiPON thin-film solid electrolyte. Optimized pulsed laser deposition (PLD) growth produced polycrystalline FeF2 films with excellent phase purity and P42/mnm crystallographic symmetry. A schematic band diagram was deduced using a combination of UPS, XPS and UV-Vis spectroscopies. Room temperature Hall measurements reveal that as-deposited FeF2 is n-type with an electron mobility of 0.33 cm2/V.s and a resistivity was 0.255 Ω.cm. The LiPON films were deposited by reactive sputtering in nitrogen, and the results indicate that the ionic conductivity is dependent on the amount of nitrogen incorporated into the film during processing. The highest ionic conductivity obtained was 1.431.9E-6 Scm-1 and corresponded to a chemical composition of Li1.9PO3.3N.21. FeF2/LiPON thin films microbatteries were assembled using a 2032 coin cell configuration and subjected to Galvanostatic cycling. HRTEM and EELS spectroscopy where performed across the FeF2/LiPON interface of samples cycled once 15 times in their lithiated and delithiated states to understand the relationship between microstructural evolution and capacity. The EELS measurements provided evidence of a three-phase conversion reaction over the first discharge described by FeF2 +2e-+2Li+↔Fe +LiF, and of incomplete reconversion back to FeF2 after the 1st cycle resulting in new Fe0 and LiF phases in delithiated samples. This incomplete conversion results in (a) a smaller phase fraction of FeF2 participating in the conversion process subsequently and (b) the formation of LiF which is resistive to both electron and ion transport. This results in the observed drastic drop in capacity after the1st cycle. More study to understand the reconversion reaction pathways is required to fully exploit the potential of FeF2 and other conversion materials as cathodes in Li ion batteries. digital.library.unt.edu/ark:/67531/metadc804977/
A Guide to Arranging Late Eighteenth and Early Nineteenth Century Harmoniemusik in an Historical Style
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The system of higher education in the United States of America has retained some of its original character yet it has also grown in many ways. Among the contemporary priorities of colleges and universities are undergraduate student learning outcomes and success along with a growing focus on diversity. As a result, there has been a growing focus on ways to achieve compositional diversity and a greater sense of inclusion with meaningful advances through better access and resources for individuals from non-dominant populations. The clearest result of these advances for sexual and gender diversity has been a normalization of lesbian, gay, bisexual, transgender, and queer (LGBTQ) identities through positive visibility and greater acceptance on campus. However, it appears that relatively few institutions have focused on improving academic diversity and students’ cognitive growth around LGBTQ issues. Through historical inquiry and a qualitative approach, this study explored the fundamental aspects of formal LGBTQ studies academic programs at some of the leading American research universities, including Cornell University, the University of Maryland, College Park, and the University of Texas at Austin – a purposeful sample chosen from the Association of American Universities (AAU) member institutions with organized curricula focused on the study of sexual and gender diversity. The analysis of primary and secondary sources, including documents and interviews, helped create historical narratives that revealed: a cultural shift was necessary to launch a formal academic program in LGBTQ studies; this formalization of LGBTQ studies programs has been part of the larger effort to improve the campus climate for sexual and gender diversity; and there has been a common pattern to the administration and operation of LGBTQ studies. Clearly, the research shows that LGBTQ studies, as a field of study and formal curriculum, has become institutionalized at the American research university. A key outcome of this research is the creation of a historiography of curricular development around sexual and gender diversity at a sample of premier research universities. This work also begins to fill the gap in the study of academic affairs at the postsecondary level of education related to LGBT and queer studies and the organization and administration of learning about diversity and inclusion. Ultimately, the results of this study can influence the continued advancement and maturity of this legitimate field of study as well as academic diversity and social transformation around sexual and gender diversity. digital.library.unt.edu/ark:/67531/metadc804893/
Does Device Matter? Understanding How User, Device, and Usage Characteristics Influence Risky It Behaviors of Individuals
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Over the past few years, there has been a skyrocketing growth in the use of mobile devices. Mobile devices are ushering in a new era of multi-platform media and a new paradigm of “being-always-connected”. The proliferation of mobile devices, the dramatic growth of cloud computing services, the availability of high-speed mobile internet, and the increase in the functionalities and network connectivity of mobile devices, have led to creation of a phenomenon called BYOD (Bring Your Own Device), which allows employees to connect their personal devices to corporate networks. BYOD is identified as one of the top ten technology trends in 2014 that can multiply the size of mobile workforce in organizations. However, it can also serve as a vehicle that transfers cyber security threats associated with personal mobile devices to the organizations. As BYOD opens the floodgates of various device types and platforms into organizations, identifying different sources of cyber security threats becomes indispensable. So far, there are no studies that investigated how user, device and usage characteristics affect individuals’ protective and risky IT behaviors. The goal of this dissertation is to expand the current literature in IS security by accounting for the roles of user, device, and usage characteristics in protective and risky IT behaviors of individuals. In this study, we extend the protection motivation theory by conceptualizing and measuring the risky IT behaviors of individuals and investigating how user, device, and usage characteristics along with the traditional protection motivation factors, influence individuals’ protective and risky IT behaviors. We collected data using an online survey. The results of our study show that individuals tend to engage in different levels of protective and risky IT behaviors on different types of devices. We also found that certain individual characteristics as well as the variety of applications that individuals use on their computing devices, influence their protective and risky IT behaviors. digital.library.unt.edu/ark:/67531/metadc804895/
Through the Lenses of Ray Bankston and Don Shugart: Horse Photos from the University of North Texas Libraries
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The selected Horse Photos in this book represent samples images produced by the two most prolific equine photographers, Ray Bankston and Don Shugart between 1962 and 2000. While Ray Bankston and Don Shugart traveled extensively, many of their clients, including prominent ranches and prestigious performance horse events, were located in Texas, home of the American Quarter Horse Association, the National Cutting Horse Association, and the American Paint Horse Association. In addition to formal portraits of famous horses and their owners and riders, their photo collections also contain never-before-published informal shots of riders and horse-show exhibitors, as well as those of farms, ranches, rodeo arenas, and performance rings of a bygone era. Where available, the dates when horses were photographed are noted, as well as the names of their owners, riders, trainers, and the ranches and farms that represent them. digital.library.unt.edu/ark:/67531/metadc802019/
Sources of Organizational Resilience During the 2012 Korean Typhoons: an Institutional Collective Action Framework
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The objective of this proposed research is to test whether interorganizational collaboration contributes to the ability of an organization to bounce back swiftly from disasters. The research questions are examined from the Institutional Collective Action (ICA) perspective. The general argument of this dissertation is that organizational resilience can be explained by interorganizational collaboration. The ICA framework, specifically, identifies two general network structures to explain strategies that can be adopted to minimize collaboration risks: bonding and bridging structures. This dissertation focuses on how governmental and nongovernmental organizations in South Korea collaborated. The data was collected from the southeastern tip of the Korean Peninsula in August of 2012, and January of 2013. The 2012 Typhoons devastated the area after the first data set was collected in August 2012, causing the loss of estimated US$ 730 million and 29 fatalities. Afterward, the second survey was administrated in January of 2013 to gauge respondents’ views on how organizations responded to the disasters. This dissertation consists of three essays. The first essay presents a brief overview and assessment of the current research on resilience. The second essay empirically tests the sources of organization resilience. The third essay examines the dynamic nature of interorganizational ties by employing stochastic actor-based models. The findings show how organizations prefer to not coordinate with other organizations even though this could reduce their strains during a disaster. The findings also suggest that organizations that operate in higher risk areas or participate in joint full-scale exercises before a disaster form interorganizational ties afterward. digital.library.unt.edu/ark:/67531/metadc801952/
Characteristics of Primary Cilia and Centrosomes in Neuronal and Glial Lineages of the Adult Brain
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Primary cilia are sensory organelles that are important for initiating cell division in the brain, especially through sonic hedgehog (Shh) signaling. Several lines of evidence suggest that the mitogenic effect of Shh requires primary cilia. Proliferation initiated by Shh signaling plays key roles in brain development, in neurogenesis in the adult hippocampus, and in the generation of glial cells in response to cortical injury. In spite of the likely involvement of cilia in these events, little is known about their characteristics. Centrosomes, which are associated with primary cilia, also have multiple influences on the cell cycle, and they are important in assembling microtubules for the maintenance of the cell’s cytoskeleton and cilia. The cilia of terminally differentiated neurons have been previously examined with respect to length, incidence, and receptors present. However, almost nothing is known about primary cilia in stem cells, progenitors, or differentiated glial cells. Moreover, it is not known how the properties of cilia and centrosomes may vary with cell cycle or proliferative potential, in brain or other tissues. This dissertation focuses first on neurogenesis in the hippocampal subgranular zone (SGZ). The SGZ is one of the few brain regions in mammals that gives rise to a substantial number of new neurons throughout adulthood. The neuron lineage contains a progression of identifiable precursor cell types with different proliferation rates. This present study found that primary cilia were present in every cell type in the neuronal lineage in SGZ. Cilium length and incidence were positively correlated among these cell types. Ciliary levels of adenylyl cyclase type III (ACIII) levels relative to ADP-ribosylation factor-like protein 13b (Arl13b) was higher in neurons than in precursor cells and glia, and also changed with the cell cycle. G-protein coupled receptors, SstR3, MCHR1, and Gpr161 receptors were only found in neuronal cilia. The levels and distribution of three centrosomal proteins, γ-tubulin, pericentrin and cenexin in neurons was different from the distributions in precursors and glia. The second focus of study is glial responses to injury in the neocortex, which has been widely studied as an injury model. This study found that in the normal adult somatosensory cortex, primary cilia were present in astrocytes and polydendrocytes but not in microglia. Following injury, the incidence of primary cilia decreased in astrocytes. Also, a new cell type expressing GFAP, NG2 and Olig2 was seen 3 days following injury, but was not present in normal mice. The characteristics of primary cilia and centrosome described here suggest that in stem cells and progenitors their characteristics may be well suited for proliferation, whereas in neurons, the cilia and centrosomes are important for other sensory functions. digital.library.unt.edu/ark:/67531/metadc801939/
The Effect of Curcumin Supplementation on Physical and Biological Indices of Delayed Onset Muscle Soreness and Inflammation Following Muscle Injury
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In this project, the effects of dietary polyphenols on exercise-induced muscle damage and vascular health are examined. Dietary polyphenols exert well-known anti-inflammatory effects; however, how these effects are realized with respect to vascular health and EIMD is relatively unknown. I begin by reviewing the available literature surrounding the impact of three dietary polyphenols (curcumin, catechins, and quercetin) on inflammation associated with EIMD. It is well established that their primary means of anti-inflammation is through alterations of NF-κB and AP-1 transcription activities. Given this, their inclusion into training strategies seems reasonable. Consistent evidence is presented making a case for the anti-inflammatory effects of dietary polyphenols following EIMD. I follow this review up by completing an in-depth study on the consumption of curcumin prior to EIMD. I found curcumin (1000 mg/day) can reduce subjective soreness and decrease inflammation compared to placebo controls. To further understand the effects of dietary polyphenols on health, I investigate the effects of a four-week supplementation period of cocoa (catechins) on vascular. I concluded that atherogenic risk in obese women is reduced after consumption of cocoa. In addition to these experimental projects, I developed two novel methods that can be used to investigate vascular health (EMP concentration) and intracellular protein and mRNA production using flow cytometry. digital.library.unt.edu/ark:/67531/metadc801906/
Space and Spectrum Engineered High Frequency Components and Circuits
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With the increasing demand on wireless and portable devices, the radio frequency front end blocks are required to feature properties such as wideband, high frequency, multiple operating frequencies, low cost and compact size. However, the current radio frequency system blocks are designed by combining several individual frequency band blocks into one functional block, which increase the cost and size of devices. To address these issues, it is important to develop novel approaches to further advance the current design methodologies in both space and spectrum domains. In recent years, the concept of artificial materials has been proposed and studied intensively in RF/Microwave, Terahertz, and optical frequency range. It is a combination of conventional materials such as air, wood, metal and plastic. It can achieve the material properties that have not been found in nature. Therefore, the artificial material (i.e. meta-materials) provides design freedoms to control both the spectrum performance and geometrical structures of radio frequency front end blocks and other high frequency systems. In this dissertation, several artificial materials are proposed and designed by different methods, and their applications to different high frequency components and circuits are studied. First, quasi-conformal mapping (QCM) method is applied to design plasmonic wave-adapters and couplers working at the optical frequency range. Second, inverse QCM method is proposed to implement flattened Luneburg lens antennas and parabolic antennas in the microwave range. Third, a dual-band compact directional coupler is realized by applying artificial transmission lines. In addition, a fully symmetrical coupler with artificial lumped element structure is also implemented. Finally, a tunable on-chip inductor, compact CMOS transmission lines, and metamaterial-based interconnects are proposed using artificial metal structures. All the proposed designs are simulated in full-wave 3D electromagnetic solvers, and the measurement results agree well with the simulation results. These artificial material-based novel design methodologies pave the way toward next generation high frequency circuit, component, and system design. digital.library.unt.edu/ark:/67531/metadc801923/
Friendship, Politics, and the Good in Aristotle's Nicomachean Ethics
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In Aristotle's Nicomachean Ethics, Books VIII and IX provide A philosophic examination of friendship. While these Books initially appear to be non sequiturs in the inquiry, a closer examination of the questions raised by the preceding Books and consideration of the discussion of friendship's position between two accounts of pleasure in Books VII and X indicate friendship's central role in the Ethics. In friendship, Aristotle finds a uniquely human capacity that helps readers understand the good is distinct from pleasure by leading them to think seriously about what they can hold in common with their friends throughout their lives without changing who they are. What emerges from Aristotle's account of friendship is a nuanced portrait of human nature that recognizes the authoritative place of the intellect in human beings and how its ability to think about an end and hold its thinking in relation to that end depends upon whether it orders or is ordered by pleasures and pains. Aristotle lays the groundwork for this conclusion throughout the Ethics by gradually disclosing pleasures and pains are not caused solely by things we feel through the senses, but by reasoned arguments and ideas as well. Through this insight, we can begin to understand how Aristotle's Ethics is a work of political philosophy; to fully appreciate the significance of his approach, however, we must contrast his work with that of Thomas Hobbes, his harshest Modern critic. Unlike Aristotle, Hobbes is nearly silent on friendship in his political philosophy, and examining his political works especially Leviathan reveals the absence of friendship is part of his deliberate attempt to advance a politics founded on the moral teaching that pleasure is the good. Aristotle's political philosophy, by way of contrast, aims to preserve the good, and through friendship, he not only disentangles the good from pleasure, but shows a level of human community more suitable for preserving the good than political regimes because these communities have more natural bonds than any regime can hope to create between its citizens. digital.library.unt.edu/ark:/67531/metadc801900/
A Restorative Environmental Justice for the Prison Industrial Complex: a Transformative Feminist Theory of Justice
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This dissertation provides a feminist restorative model of environmental justice that addresses the injustices found within UNICOR’s e-waste recycling operations. A feminist restorative environmental justice challenges the presupposition that grassroots efforts, law and policy, medical and scientific research, and theoretical pursuits (alone or in conjunction) are sufficient to address the emotional and relational harm of environmental injustices. To eliminate environmental harms, this model uses collaborative dialogue for interested parties to prevent environmental harm. To encourage participation, a feminist restorative model accepts many forms of knowledge and truth as ‘legitimate’ and offers an opportunity for women to share how their personal experiences of love, violence, and caring differ from men and other women and connect to larger social practices. This method of environmental justice offers opportunities for repair, reparation and reintegration that can transform perspectives on criminality, dangerous practices and structures in the PIC, and all persons who share in a restorative encounter. digital.library.unt.edu/ark:/67531/metadc801925/
Understanding Microbial Biodegradation of Environmental Contaminants
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The accumulation of industrial contaminants in the natural environments have rapidly become a serious threat for human and animal life. Fortunately, there are microorganisms capable of degrading or transforming environmental contaminants. The present dissertation work aimed to understand the genomic basis of microbial degradation and resistance. The focus was the genomic study of the following bacteria: a) Pseudomonas fluorescens NCIMB 11764, a unique bacterium with specific enzymes that allow cyanide adaptation features. Potential cyanide degradation mechanisms found in this strain included nit1C cluster, and CNO complex. Potential cyanide tolerance genes found included cyanide insensitive oxidases, nitric oxide producing gene, and iron metabolism genes. b) Cupriavidus sp. strain SK-3 and strain SK-4. The genome of both bacteria presented the bph operon for polychlorinated biphenyl (PCB) degradation, but we found differences in the sequences of the genes. Those differences might indicate their preferences for different PCB substrates. c) Arsenic resistant bacterial communities observed in the Atacama Desert. Specific bacteria were found to thrive depending on the arsenic concentration. Examples were Bacteroidetes and Spirochaetes phyla whose proportions increased in the river with high arsenic concentrations. Also, DNA repair and replication metabolic functions seem to be necessary for resistance to arsenic contaminated environments. Our research give us insights on how bacteria communities, not just individually, can adapt and become resistant to the contaminants. The present dissertation work showed specific genes and mechanisms for degradation and resistance of contaminants that could contribute to develop new bioremediation strategies. digital.library.unt.edu/ark:/67531/metadc801956/
Determinants of Citizens’ 311 Use Behaviors: 311 Citizen-initiated Contact, Contact Channel Choice, and Frequent Use
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Facing increasingly complex policy issues and diminishing citizen satisfaction with government and service performance, managing the quality of citizen relationship management has become a main challenge for public managers. Solutions to complex policy problems of service performance and low level of citizen participation often must be developed by encouraging citizens to make their voices heard through the various participation mechanisms. Reflecting on this need, the municipal governments in the U.S. have developed centralized customer systems for citizen relationship management. 311 centralized customer system (named 311 in this study) has the functions of citizen-initiated contact, service-coproduction, and transaction, and many local governments launch 311 to maintain or enhance their relationship with the public. Using 311 is an easy and free technically for citizens, but ensuring some degree of citizen engagement and citizens’ 311 use has been challenging for local public managers of municipalities. Despite calls for the importance of 311 in the service and information delivery process, fair treatment and access to use of governmental information, citizen participation, government responsiveness, and citizen satisfaction, to the best of our understanding, no empirical studies explore citizens’ 311 behaviors in the micro and individual level in the field of public administration. This dissertation provides a comprehensive understanding of the 311 centralized customer system, helps local public managers know citizens’ perceived perspectives toward the operation of 311, and assists these managers to develop an effective 311 system in municipalities. The dissertation’s main purpose is to clarify the importance of 311 to citizen relationship management and provide insights into citizens’ 311 use behaviors. More specifically, this dissertation tries to answers the following questions: a. Why do citizens use 311? Do the various groups of the population access and use 311 in San Francisco equally? If not, what factors influence the citizens’ 311 citizen-initiated contact behaviors? b. Why do citizens choose the 311 digital channel to contact with local governments? c. Why do citizens use 311 frequently? This dissertation will address these questions and draws on data from the 2011 citizen survey of City of San Francisco to explore citizens’ 311 use behaviors by examining them from citizens’ perspectives. The main arguments of each question listed above are: 1. 311 citizen-initiated contact is different from traditional citizen-initiated contact, and exposure to governmental-ICT environment, gender, income, and race are the factors influencing 311 citizen-initiated contact. 2. The digital divide, including the social side of the digital divide and access-side of the digital divide, influences citizens’ 311 channel choice. 3. Citizens’ technology acceptance, citizen satisfaction, and frequent use of public services influence the frequency of citizens’ 311 use. digital.library.unt.edu/ark:/67531/metadc801912/
Explaining Economic Development Strategies Using Product Differentiation Theory: a Reconceptualization of Competition Among City Governments
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Local governments do not operate in a vacuum. Instead, they are part of a complex “polycentric” system of governments where politically autonomous and self-ruled cities compete with one another over taxable wealth. Missing from the scholarship on metropolitan governance is an understanding of the factors driving competition among local governments. The purpose of this dissertation is to fill this gap by examining how interjurisdictional competition over economic development impacts a city’s choice of strategies for attracting business and residential investment and how those strategies affect revenue collection. First, this dissertation examines whether cities, knowing the economic development strategies of their neighboring cities, pursue similar types of businesses? Or do cities strategically target different types of businesses as a way to avoid the negative consequences of competition? Second, this dissertation explores what impact the decision to pursue similar or dissimilar businesses has on the revenue collection of local governments. Using spatial data analysis to analyze a sample of 2,299 cities, this dissertation finds general support for both theoretical frameworks presented. Overall, the findings from both analyses provide unique insights into metropolitan governance and interjurisdictional competition. digital.library.unt.edu/ark:/67531/metadc801942/
(Some More) American Literature
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This short story collection consists of twenty short fictions and a novella. A preface precedes the collection addressing issues of craft, pedagogy, and the post Program Era literary landscape, with particular attention paid to the need for empathy as an active guiding principle in the writing of fiction. digital.library.unt.edu/ark:/67531/metadc801908/
Application of Cyclic Polarization of Aluminum 3003 Used in All-aluminum Microchannel Heat Exchangers
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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 than that of SWAAT and results obtained in this test is more reproducible compared to those of SWAAT. Scanning electron microscopy micrographs show typical pit depths of about 50 μm. digital.library.unt.edu/ark:/67531/metadc801930/
Effects of Auditor-provided Tax Services on Book-tax Differences and Investors’ Mispricing of Book-tax Differences
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In this study, I investigate the effect of auditor-provided tax services (ATS) on firms’ levels of book-tax differences and investors’ mispricing of book-tax differences. The joint provision of audit and tax services has been a controversial issue among regulators and academic researchers. Evidence on whether ATS improve or impair the overall accounting quality is inconclusive as a result of the specific testing circumstances involved in different studies. Book-tax differences capture managers’ earnings management and/or tax avoidance intended to maximize reported financial income and to minimize tax expense. Therefore, my first research question investigates whether ATS improve or impair audit quality by examining the relation between ATS and firms’ levels of book-tax differences. My results show that ATS are negatively related to book-tax differences, suggesting that ATS improve the overall audit quality and reduce aggressive financial and/or tax reporting. My second research question examines whether the improved earnings quality for firms acquiring ATS leads to reduced mispricing of book-tax differences among investors. Recent studies document that despite the rich information about firms’ future earnings contained in book-tax differences, investors process such information inefficiently, leading to systematic pricing errors among firms with large book-tax differences. My empirical evidence indicates that ATS mitigate such mispricing, with pricing errors being lower among firms acquiring ATS compared with firms without ATS. Collectively, these results support the notion that ATS improve audit quality through knowledge spillover. Moreover, the improved earnings quality among firms acquiring ATS in turn helps reduce investors’ mispricing of book-tax differences. digital.library.unt.edu/ark:/67531/metadc801928/
Belief Transfers in Co-branding and Brand Extension and the Roles of Perceptual Fit
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Existing co-branding and brand extension research generally coalesces around two important constructs: perceptual fit and attitude toward the brand. Studies in co-branding and brand extension to date have generally emphasized the transference of affective elements of attitude from parent brand to the extension. Researchers and practitioners clearly need to learn more about the transfer of belief, the cognitive elements of attitude. Too little is currently known about whether and how beliefs are actually transferred in co-branding and brand extension applications, particularly in terms of perceptual fit. This dissertation investigates belief transfer and the effect of perceptual fit on belief transfer in co-branding and brand extension scenarios and develops answers to the following research questions: 1.Are different categories of beliefs transferable from parent brand to theextension? 2.How do various sub-dimensions of perceptual fit affect belief transfers fromparent brands to the extension? 3.How do different categories of beliefs affect consumers’ intentions to purchasethe extension products? Categorization Theory was used as the fundamental theory to build the hypotheses. This dissertation involved qualitative studies, belief scale development, and experimental design studies. The results revealed that aesthetic and functional beliefs are positively transferred from parent brand to the extension. The transfer of aesthetic beliefs is affected by the level of brand fit while the transfer of functional beliefs is independent upon the level of any perceptual fit construct. Finally, cognitive structure based on the strength of extension beliefs is more predictive upon the purchase intention. Findings will extend the co-branding and brand extension literature, especially in terms of the pattern of belief transfers that unfold subject to the influence of various perceptual fit constructs. The results will also provide additional insights about the role that perceptual fit plays in influencing categories of consumer beliefs as those beliefs are also influenced by the specific perceptual fits that are presumably transferred to the extension. digital.library.unt.edu/ark:/67531/metadc801896/
Forward Genetic Characterization of Medicago Truncatula Tnt1 Insertion Mutants Defective in Nodule Development and Symbiotic Nitrogen Fixation
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Legumes are unique plants because they form special structures “nodules”, via symbiotic relationships with rhizobial bacteria present in the soil. Once rhizobia mature inside nodules, they fix atmospheric nitrogen providing a source of bioavailable nitrogen to the plant. To discover novel genetic components involved in the legume-rhizobia symbiosis by using forward genetic screening, we have isolated Medicago truncatula Tnt1 insertion mutants in the R108 ecotype, which are defective in nodule development and symbiotic nitrogen fixation in response to Sinorhizobium meliloti. Out of three mutants NF11044, NF11217 and NF8324, one of the mutants showed brown nodules and Fix- phenotype that is defective in symbiotic nitrogen fixation. The other two mutants showed white nodules and Fix- phenotype, also indicator of defects in symbiotic nitrogen fixation. To identify the underlying mutation causing the phenotype, we have developed molecular genetic markers by obtaining genomic sequences flanking the Tnt1 insertions by TAIL-PCR and Illumina sequencing. To carry out co-segregation analysis, back-crossed BC1F2 segregating populations were obtained. These are being phenotyped, genotyped and analyzed for co-segregation of the phenotype with the Tnt1 genetic markers. Back-crossing also has the effect of reducing the Tnt1 insertions, which are not linked to the nodulation defective phenotypes. Out of the three mutants, NF8324 harbors exactly the same insertion as in the rsd-1 Tnt1 mutant NF11265. The defect in NF11217 is caused by a Tnt1 insertion in the previously described PLC gene; the site of this insertion is close to that found in a different mutant, NF0217. For mutant NF11044, we developed linkage markers that place the defective locus on chromosome 7. To further characterize co-segregation in NF11044, a mapping population has been created by crossing the mutant with other ecotypes: A17 and A20. We tested mutants and wild type plants with linkage marker A20 X NF11044 BC1F2 that segregates 3:1(wild type: mutant). The recombination frequency ratio is similar as compared to back-crosses to ecotype R108. However, we did not observe mutant phenotypes in the A17 X NF11044 BC1F2 population. Future identification of the defective gene and functional characterization of it once it is identified will be carried out to better understand the mechanism of nodule organogenesis and symbiotic nitrogen fixation. digital.library.unt.edu/ark:/67531/metadc801877/
Manipulations of Sucrose/proton Symporters and Proton-pumping Pyrophosphatase Lead to Enhanced Phloem Transport But Have Contrasting Effects on Plant Biomass
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Delivery of photoassimilate, mainly sucrose (Suc) from photoautotrophic source leaves provides the substrate for the growth and maintenance of sink tissues such as roots, storage tissues, flowers and fruits, juvenile organs, and seeds. Phloem loading is the energized process of accumulating solute in the sieve element/companion cell complex of source leaf phloem to generate the hydrostatic pressure that drives long-distance transport. In many plants this is catalyzed by Suc/Proton (H+) symporters (SUTs) which are energized by the proton motive force (PMF). Overexpression of SUTs was tested as means to enhance phloem transport and plant productivity. Phloem specific overexpression of AtSUC2 in wild type (WT) tobacco resulted in enhanced Suc loading and transport, but against the hypothesis, plants were stunted and accumulated carbohydrates in the leaves, possibly due to lack of sufficient energy to support enhanced phloem transport. The energy for SUT mediated phloem loading is provided from the PMF, which is ultimately supplied by the oxidation of a small proportion of the loaded photoassimilates. It was previously shown that inorganic pyrophosphate (PPi) is necessary for this oxidation and overexpressing a proton-pumping pyrophosphatase (AVP1) enhanced both shoot and root growth, and augmented several energized processes like nutrient acquisition and stress responses. We propose that AVP1 localizes to the PM of phloem cells and uses PMF to synthesize PPi rather than hydrolyze it, and in doing so, maintains PPi levels for efficient Suc oxidation and ATP production. Enhanced ATP production in turn strengthens the PMF via plasma membrane (PM) ATPase, increasing phloem energization and phloem transport. Phloem-specific and constitutive AVP1 overexpressing lines showed increased growth and more efficiently moved carbohydrates to sink organs compared to WT. This suggested changes in metabolic flux but diagnostic metabolites of central metabolism did not show changes in steady state levels. This research focuses on fundamental aspects of carbon utilization and transport, and has a strong applied component, since increased H+-PPase activity enhances plant biomass, nutrient up-take capacities, and stress tolerance for as yet not fully characterized reasons. digital.library.unt.edu/ark:/67531/metadc801879/
Journal of Applied Rehabilitation Counseling, Volume 46, Number 4, Winter 2015
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Journal of Applied Rehabilitation Counseling is the official publication of the National Rehabilitation Counseling Association (NRCA). The JARC is published quarterly, Spring, Summer, Fall and Winter. JARC is a journal of opinion and research in professional rehabilitation counseling and addresses the needs of individuals employed in a wide variety of work settings and with wide-ranging professional interests. In this edition of JARC, Vol. 46, No.4 (Winter 2015), the following five articles were included: -Emerging Adults with Disabilities: Theory, Trends, and Implications (Jill M. Meyer, Vanessa M. Hinton, and Nicholas Derzis) -Substance Abuse among the Elderly Population: Overview and Management (Amani A. Kettaneh) -Assessing Faculty Attitudes toward Universal Design Instructional Techniques (Bryan K. Dallas and Matthew E. Sprong) -Clinical Supervisors' Perceptions of Counselor Characteristics Associated with Effective and Well-Balanced Practices (Margaret Glenn, Monica Leppma, and Kendra Thorne) -Thinking Outside the Box: Maximizing Vocational Outcomes Post-Traumatic Brain Injury through Rehabilitation Counseling and Recreation/Leisure Activities (Leah Cox Thomas, Eileen J. Burker, and Kelly A. Kazukauskas). digital.library.unt.edu/ark:/67531/metadc799761/
Journal of Applied Rehabilitation Counseling, Volume 46, Number 3, Fall 2015
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Journal of Applied Rehabilitation Counseling is the official publication of the National Rehabilitation Counseling Association (NRCA). The JARC is published quarterly, Spring, Summer, Fall and Winter. JARC is a journal of opinion and research in professional rehabilitation counseling and addresses the needs of individuals employed in a wide variety of work settings and with wide-ranging professional interests. In this edition of JARC (Vol. 46, No.3), the following articles were included: -Operationalizing Compassion in the VR Process (James M. Grover) -Education and Employment Outcomes from the RSA Data File for Transition-Age African American, White, and Hispanic Youth with Learning Disabilities (Eun Ji, James Schaller, Barbara Pazey, and Kate Glynn) -An Exploration of Work Incentive Benefits Specialists' Experiences (Ellie C. Hartman, Catherine A. Anderson, Jacob Yuichung Chan, Juliet H. Fried, & John W. Lui) -Forgiveness and Disability: Reconsideration of Forgiveness as a Vital Component of the Rehabilitation Counseling Profession (Susan Stuntzner & Jacquelyn Dalton) -Boundaries with Social Media: Ethical Considerations for Rehabilitation Professionals (Ashley K. Crtalic, Reg L. Gibbs, Matthew E. Sprong, & Tom F. Dell) digital.library.unt.edu/ark:/67531/metadc799760/
Interaction of Plasmons and Excitons for Low-Dimension Semiconductors
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The effects of surface plasmon for InGaN/GaN multi-quantum wells and ZnO nanoparticles optical linear and nonlinear emission efficiency had been experimentally studied. Due to the critical design for InGaN MQWs with inverted hexagonal pits based on GaN, both contribution of surface plasmon effect and image charge effect at resonant and off resonant frequencies were experimentally and theoretically investigated. With off- resonant condition, the InGaN MQWs emission significantly enhanced by metal nanoparticles. This enhancement was caused by the image charge effect, due to the accumulation of carriers to NPs region. When InGaN emission resonated with metal particles SP modes, surface Plasmon effect dominated the emission process. We also studied the surface plasmon effect for ZnO nanoparticles nonlinear optical processes, SHG and TPE. Defect level emission had more contribution at high incident intensity. Emissions are different for pumping deep into the bulk and near surface. A new assumption to increase the TPE efficiency was studied. We thought by using Au nanorods localized surface plasmon mode to couple the ZnO virtual state, the virtual state’s life time would be longer and experimentally lead the emission enhancement. We studied the TPE phenomena at high and near band gap energy. Both emission intensity and decay time results support our assumption. Theoretically, the carriers dynamic mechanism need further studies. digital.library.unt.edu/ark:/67531/metadc799475/
Assessing Terrorist Cyber Threats: Engineering a Functional Construct
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Terrorist organizations and individuals make use of the Internet for supportive activities such as communication, recruiting, financing, training, and planning operations. However, little is known about the level of computer-based (“cyber”) threat such terrorist organizations and individuals pose. One step in facilitating the examination and assessment of the level of cyber threat posed by terrorist organizations and individuals is development of an assessment tool or methodology. This tool would guide intelligence collection efforts and would support and facilitate comparative assessment of the cyber threat posed by terrorist organizations and individuals through the provision of a consistent method of assessment across time, amongst organizations and individuals, and between analysts. This study leveraged the professional experience of experts to engineer a new functional construct – a structured analytical technique designed to assess the cyber threat posed by terrorist entities and individuals. The resultant instrument was a novel structured analytical construct that uses defined indicators of a terrorist organization/individual’s intent to carry out cyber attacks, and their capability to actually do so as measures of an organization/individual’s overall level of cyber threat. digital.library.unt.edu/ark:/67531/metadc799463/
Electromagnetically Modulated Sonic Structures
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Phononic crystals are structures composed of periodically arranged scatterers in a background medium that affect the transmission of elastic waves. They have garnered much interest in recent years for their macro-scale properties that can be modulated by the micro-scale components. The elastic properties of the composite materials, the contrast in the elastic properties of the composite materials, and the material arrangement all directly affect how an elastic wave will behave as it propagates through the sonic structure. The behavior of an elastic wave in a periodic structure is revealed in its transmission bandstructure, and modification of any the elastic parameters will result in tuning of the band structure. In this dissertation, a phononic crystal with properties that can be modulated using electromagnetic radiation, and more specifically, radio-frequency (RF) light will be presented. digital.library.unt.edu/ark:/67531/metadc799496/
Not All Truth Commissions Are Alike: Understanding Their Limitations and Impact
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This dissertation project develops a theoretical understanding of how truth commissions achieve legitimacy and thus contribute to peace and stability in the aftermath of major traumatic events (e.g. civil war, mass killings, regime changes). I identify three components of truth commission legitimacy---authority, fairness, and transparency---that facilitate beneficial outcomes for societies emerging from a period of severe human rights repression or civil war. I theorize and test how institutions with these legitimacy characteristics contribute to an increase in respect for human rights and decrease political violence in transitioning societies, thus contributing to peace and stability. In order to test the hypothesized relationships, I create a truth commission characteristic dataset that provides greater detail than existing datasets. This project is a contribution to our understanding of the relationships between human rights, institutions, conflict, and international law. It provides one explanation for the inconsistent findings of extant work concerning the impact of transitional justice, generally and truth commissions, specifically. I provide evidence that there are identifiable "best practices" that truth commissions should consider adopting. This information can assist states, intergovernmental organizations, and nongovernmental organizations alike in making difficult decisions regarding the transitional justice process, which is expensive and time consuming further necessitating an understanding of what practices are most crucial for achieving peace and stability. digital.library.unt.edu/ark:/67531/metadc799497/
Surface Topography and Aesthetics of Recycled Cross-Linked Polyethylene Wire and Cable Coatings
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Our research focuses on re-using a waste a material, cross-linked polyethylene abbreviated XLPE, which is a widely used coating for wires. XLPE is strong and has excellent thermal properties due to its chemical structure - what leads to the significance of recycling this valuable polymer. Properties of XLPE include good resistance to heat, resistance to chemical corrosion, and high impact strength. A wire is usually composed of a metal core conductor and polymeric coating layers. One creates a new coating, including little pieces of recycled XLPE in the lower layer adjacent to the wire, and virgin XLPE only in the upper layer. Industries are often wasting materials which might be useful. Mostly, some returned or excess products could be recycled to create a new type of product or enable the original use. This method helps cleaning the waste, lowers the costs, and enhances the income of the manufacturing company. With the changing of the thickness of the outer layer, the roughness changes significantly. Moreover, different processing methods result in surfaces that look differently. digital.library.unt.edu/ark:/67531/metadc799512/
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