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 Collection: UNT Theses and Dissertations
Design, Synthesis and Study of Supramolecular Donor – Acceptor Systems Mimicking Natural Photosynthesis Processes

Design, Synthesis and Study of Supramolecular Donor – Acceptor Systems Mimicking Natural Photosynthesis Processes

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Date: December 2015
Creator: KC, Chandra Bikram
Description: 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 ...
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Dynamic Behaviors of Historical Wrought Iron Truss Bridges – a Field Testing Case Study

Dynamic Behaviors of Historical Wrought Iron Truss Bridges – a Field Testing Case Study

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Date: December 2015
Creator: Hedric, Andrew C.
Description: 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. ...
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Environmental Modulation of the Onset of Air-breathing of the Siamese Fighting Fish and the Blue Gourami

Environmental Modulation of the Onset of Air-breathing of the Siamese Fighting Fish and the Blue Gourami

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Date: December 2015
Creator: Mendez Sanchez, Jose Fernando
Description: 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 ...
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Fashioning Society in Eighteenth-century British Jamaica

Fashioning Society in Eighteenth-century British Jamaica

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Date: December 2015
Creator: Northrop, Chloe A.
Description: 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 ...
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The Forty-fifth Illinois Volunteer Infantry Regiment: the Washburne Lead Mine Regiment in the Civil War

The Forty-fifth Illinois Volunteer Infantry Regiment: the Washburne Lead Mine Regiment in the Civil War

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Date: December 2015
Creator: Mack, Thomas B.
Description: 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, ...
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Ghost Machine

Ghost Machine

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Date: December 2015
Creator: Whitby, Bess
Description: 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.
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Identification of Hox Genes Controlling Thrombopoiesis in Zebrafish

Identification of Hox Genes Controlling Thrombopoiesis in Zebrafish

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Date: December 2015
Creator: Sundaramoorthi, Hemalatha
Description: 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 ...
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Lone Star Insanity: Efforts to Treat the Mentally Ill in Texas, 1861-1929

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

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Date: December 2015
Creator: Boyd, Dalton T.
Description: 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 ...
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Mobile Learning: Factors That Influence University Students’ Intention to Use Smartphones

Mobile Learning: Factors That Influence University Students’ Intention to Use Smartphones

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Date: December 2015
Creator: Hossain, Akhlaq
Description: 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 ...
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Montesquieu, Diversity, and the American Constitutional Debate

Montesquieu, Diversity, and the American Constitutional Debate

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Date: December 2015
Creator: Drummond, Nicholas W.
Description: 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.
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