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Stress Response by Alternative Σ-factor, Rpoh, and Analysis of Posttranslational Modification of the Heat Shock Protein, Dnak, in Escherichia Coli

Stress Response by Alternative Σ-factor, Rpoh, and Analysis of Posttranslational Modification of the Heat Shock Protein, Dnak, in Escherichia Coli

Date: May 2015
Creator: Martinez, Sarah N
Description: Bacteria have developed specialized responses that involve the expression of particular genes present in a given regulon. Sigma factors provide regulatory mechanisms to respond to stress by acting as transcriptional initiation factors. This work focuses on σ32 during oxidative stress in Escherichia coli. The differential response of key heat shock (HS) genes was investigated during HS and oxidative stress using qPCR techniques. While groEL and dnaJ experienced increases in transcriptional response to H2O2 (10 mM), HS (42°C), and paraquat (50 mM) exposure, the abundance of dnaK over the co-chaperones was apparent. It was hypothesized that DnaK undergoes oxidative modification by reactive carbonyls at its Lys-rich C-terminus, accounting for the differential response during oxidative stress. A σ32-mediated β-galactosidase reporter was devised to detect the activity of wild-type DnaK and DnaKV634X modified to lack the Lys-rich C-terminus. Under unstressed conditions and HS, σ32 was bound at the same rate in both strains. When subjected to H2O2, the WT DnaK strain produced significantly higher β-galactosidase than DnaKV634X (one-tailed Student’s t test p=0.000002, α=0.05) and approached the same level of output as the lacZ positive control. The β-galactosidase assay indicates that DnaK undergoes Lys modification in the WT strain, preventing the protein from binding ...
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Sources of Organizational Resilience During the 2012 Korean Typhoons: an Institutional Collective Action Framework

Sources of Organizational Resilience During the 2012 Korean Typhoons: an Institutional Collective Action Framework

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Date: May 2015
Creator: Jung, Kyujin
Description: 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 ...
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Three Essays on Insurers’ Performance and Best’s Ratings

Three Essays on Insurers’ Performance and Best’s Ratings

Date: May 2015
Creator: Huang, Jing‐Hui
Description: This dissertation consists of three essays: essay 1, Underwriting Use of Credit Information and Firm Performance ‐ An Empirical Study of Texas Property‐Liability Insurers, essay 2, Prediction of Ratings in Property‐Liability Industry when The Organizational Form Is Endogenous, and essay 3, A Discussion of Parsimonious Methods Predicting Insurance Companies Ratings. The purpose of the first essay is to investigate the influence of underwriting use of credit information on variation in insurers’ underwriting performance. Specifically, this study addresses the following two research questions: first, what firm‐level characteristics are associated with the insurers’ decision to use credit information in underwriting? second, is there a relationship between the use of credit information and variation in insurers’ underwriting performance? The empirical results indicate that larger insurance companies, companies having more business in personal auto insurance, and those with greater use of reinsurance are more likely to use credit information in underwriting. More importantly, the results indicate that use of credit information is associated with lower variation in underwriting performance, consistent with the hypothesis that use of credit information enables insurers to better predict their losses. The purpose of the second essay is to resolve the inconsistent relationship between the organizational forms (i.e., stock versus ...
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Prosperity Belief and Liberal Individualism: A Study of Economic and Social Attitudes in Guatemala

Prosperity Belief and Liberal Individualism: A Study of Economic and Social Attitudes in Guatemala

Date: May 2015
Creator: Huang, Lindsey A.
Description: Globalization has facilitated the growth of “market-friendly” religions throughout the world, but especially in developing societies in the global South. A popular belief among these movements is prosperity belief. Prosperity belief has several characteristics which make it compatible with liberal individualism, the dominant value in a globalized society. At the same time, its compatibility with this value may be limited, extending only to economic liberalism, but not to liberal attitudes on social issues. Data from the Pew Forum on Religious and Public Life’s 2006 survey Spirit and Power: Survey of Pentecostals in Guatemala is used to conduct a quantitative analysis regarding the economic and social attitudes of prosperity belief adherents in Guatemala in order to examine the potential, as well as the limits, of this belief’s compatibility with liberal individualism. Results suggest that support for liberal individualism is bifurcated. On one hand there is some support for the positive influence of prosperity belief on economic liberalism in regards to matters of free trade, but on the other hand, prosperity belief adherents continue to maintain conservative attitudes in regards to social issues. As prosperity belief and liberal individualism continue to grow along global capitalism, these findings have implications for the future ...
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Characteristics of Primary Cilia and Centrosomes in Neuronal and Glial Lineages of the Adult Brain

Characteristics of Primary Cilia and Centrosomes in Neuronal and Glial Lineages of the Adult Brain

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Date: May 2015
Creator: Bhattarai, Samip Ram
Description: 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 ...
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Gracias a La Nacionalización De Los Hidrocarburos: a Critical Analysis of Bolivia’s Transition to Compressed Natural Gas

Gracias a La Nacionalización De Los Hidrocarburos: a Critical Analysis of Bolivia’s Transition to Compressed Natural Gas

Date: May 2015
Creator: McCollum, Jerl Levi
Description: This paper critically analyzes the implementation of compressed natural gas and the ways in which it creates discourse in urban Bolivia. The rapidly developing nation is keen on making ubiquitous use of compressed natural gas a reality by issuing subsidies, citing increased mobility, savings, and environmental stewardship as the primary motives. Currently, eight out of every 10 public vehicles in Bolivia are powered by compressed natural gas. Through semi-structured interviews, questionnaires and secondary data collection, this paper elucidates the transitional process of building a natural gas-based transport network through discursive governance. This work draws on the critical discourse analysis literature to dissect disaggregated modal preference data, government documents, and news articles collected in Santa Cruz, Latin America's second fastest growing city. Moreover, this paper identifies and examines the ways in which the counter-discourse impacts the transformation of the country’s energy matrix. Results show that Bolivian automobile owners are reluctant to convert their automobiles, despite reduced transportation costs, stating that minimal compressed natural gas infrastructure exists outside of urban areas, and the conversion damages their vehicles’ motor. Additionally, the research reveals that automobile owners are currently the main beneficiaries, though respondents who do not posses an automobile speak more favorably of ...
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The Intervention of Human Modifications on Plant and Tree Species in the Landscape of the Lbj National Grasslands

The Intervention of Human Modifications on Plant and Tree Species in the Landscape of the Lbj National Grasslands

Date: May 2015
Creator: Lang, Brett M.
Description: An analysis utilizing both ArcGIS and ethnographic interviews from private land owners and environmental professionals examined how man-made landscape changes affected plant and tree species in the LBJ National Grasslands in Wise County, Texas north of Decatur. From the late 1800s to the Dust Bowl Era the land was used for crop production and cattle grazing resulting in erosion and loss of soil nutrients. The research indicated by 2001 that cattle grazing and population increase resulted in land disturbance within the administrative boundary of the national grasslands. Participants expressed concern over the population increase and expansion of 5 to 10 acre ranchettes for cattle grazing common in modern times. Recommendations for the future included utilizing and expanding the resources already existing with environmental professionals to continue controlling erosion.
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Ideal Learning Spaces: the Student Perspective

Ideal Learning Spaces: the Student Perspective

Date: May 2015
Creator: Sidler, Elizabeth D.
Description: Classrooms, libraries, student unions, and university campuses shape students’ learning experiences. These physical learning spaces set the stage for college student engagement and academic performance. Most of the research about the role of physical spaces in learning lacks the student perspective. The goal of this study was to offer a student-centered vision of ideal learning spaces. Students are the learners for whom learning spaces are designed, and this thesis examines the way students of one summer class at Oklahoma Baptist University conceptualized and interacted with their learning spaces. Data collection included surveys of the students, a focus group with members of the class, participant observation in the classroom, and interviews with students and the professor. Students viewed physical spaces as the backdrop for human action and chose spaces that supported their learning styles and goals. Students described supportive spaces as warm, purposefully crafted spaces, and full of other people who were seriously pursuing the same goals. This thesis explores the ways students conceptualized and interacted with learning spaces as a network of support for their learning and provides recommendations for the design of learning spaces that facilitate this support.
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An Analysis of Market Efficiency for Exchange-traded Foreign Exchange Options on an Intraday Basis

An Analysis of Market Efficiency for Exchange-traded Foreign Exchange Options on an Intraday Basis

Date: May 2015
Creator: Ren, Peter
Description: This study examines the comparative magnitude of disturbances in intraday data for exchange traded foreign exchange (FX) options. An in-depth time series analysis on the frequency and extent of discrepancies in the disturbances is conducted. The purpose of this study is twofold. First, using intraday data and trading volume, this study attempts to determine whether both put-call parity and lower boundary conditions consistently hold for exchange traded options written on U.S. dollar denominated options on the Euro trading on the Philadelphia Stock Exchange (PHLX). Second, this study attempts to investigate the magnitude of any discrepancies that may exist due to a temporary cessation of either put-call parity or lower boundary conditions. Intraday (tick-by-tick) bid prices, ask prices, and trading volume on U.S. dollar denominated European style call options and put options on the Euro are obtained. Option data is collected through a Structured Query Language (SQL) request from the Bloomberg database. Corresponding tick-by-tick spot rates for the underlying exchange rate are obtained for the same time period. Tick-by-tick 3-month Treasury bill rates are obtained to for use as the relevant risk-free interest rate. The primary data set spans an approximate one month period from 11/1/2011 to 12/6/2011. Call and option ...
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Marital Status and Racial/ethnic Differences in Health Outcomes

Marital Status and Racial/ethnic Differences in Health Outcomes

Date: May 2015
Creator: Villarreal, Cesar
Description: Substantial evidence demonstrates that marriage is associated with better health outcomes and lower mortality risk. Some evidence suggests that there are gender and race/ethnicity differences between the marriage-health benefits association. However, previous studies on marriage and health have mainly focused on non-Hispanic White-Black differences. Limited information is available regarding the roles of Hispanics. The present study examined marital status, gender, and the differences between non-Hispanic Whites, non-Hispanic Blacks, and Hispanics, in health outcomes. A retrospective cohort analysis of 24,119 Hispanic, NH White, and NH Black adults admitted to a large hospital was conducted. A total of 16,661 patients identified as either married or single was included in the final analyses. Consistent with the broader literature, marriage was associated with beneficial hospital utilization outcomes. With respect to differences in these benefits, results suggest that married patients, Hispanic patients, and women, were less likely to experience in-hospital mortality. Similar effects were observed in aggregated length of stay with married Hispanic women hospitalized nearly 2 days less than their single counterparts (6.83 days and 8.66 days, respectively). These findings support existing literature that marriage is associated with health benefits, add to the emerging research of a Hispanic survival advantage, and broaden the understanding ...
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