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Identity Issues in Asian-American Children's and Adolescent Literature (1999-2007)

Description: Published research suggests that literature should transmit ethnic and societal values as well as reassure one's own confidence and self-respect. This study provides a model for examining Asian-American children's and adolescent literature critically from the perspective of identity issues. It examines fifteen award-winning Asian-American children's and adolescent titles written by writers of that culture and published in the United States from 1999 to 2007, with a focus on Chinese (Taiwanese) American, Korean American, and Japanese American books. As published studies indicate, self, social, and ethnic identities are significantly intertwined. Hence, a content analysis was conducted based on these three major groups of categories. The findings of the study demonstrate that even though the selected books cover all three aspects of the identity issues to a certain degree, a considerably greater number of depictions of ethnic identities are made over those of internal identities and social identities. Moreover, less than half of the main characters assume an active role in improving the difficult situation. Two major voids regarding the presentation of social identities are successful social integration and positive social interactions. Recommendations for teaching, writing, illustrating, publishing, and future research are suggested, including publishing more Asian-American books which present an optimistic outlook on life, active conflict-resolving behaviors, and a balance of gender among individuals with whom the main character interacts.
Date: December 2009
Creator: Liu, Yi-chen
Partner: UNT Libraries

The impact of climate and flooding on tree ring growth of Fraxinus pennsylvanica in north-central Texas.

Description: Tree cores of Fraxinus pennsylvanica were used in a dendrochronological analysis investigating the species' responses to climate and flooding. The objective was to develop a model that incorporates the effects of precipitation, temperature, and flooding on radial growth in this species in north-central Texas. The trees exhibited strong climatic signals. The study clearly shows that all three factors have significant impacts on tree ring growth both prior to and during growth; however, the nature and extent of these impacts are highly dependent on what time of year they occur. The large temporal variations in growth responses emphasize the importance of considering the timing of environmental events when studying tree growth responses.
Date: December 2009
Creator: Komperod, Mari
Partner: UNT Libraries

Impact of Forecasting Method Selection and Information Sharing on Supply Chain Performance.

Description: Effective supply chain management gains much attention from industry and academia because it helps firms across a supply chain to reduce cost and improve customer service level efficiently. Focusing on one of the key challenges of the supply chains, namely, demand uncertainty, this dissertation extends the work of Zhao, Xie, and Leung so as to examine the effects of forecasting method selection coupled with information sharing on supply chain performance in a dynamic business environment. The results of this study showed that under various scenarios, advanced forecasting methods such as neural network and GARCH models play a more significant role when capacity tightness increases and is more important to the retailers than to the supplier under certain circumstances in terms of supply chain costs. Thus, advanced forecasting models should be promoted in supply chain management. However, this study also demonstrated that forecasting methods not capable of modeling features of certain demand patterns significantly impact a supply chain's performance. That is, a forecasting method misspecified for characteristics of the demand pattern usually results in higher supply chain costs. Thus, in practice, supply chain managers should be cognizant of the cost impact of selecting commonly used traditional forecasting methods, such as moving average and exponential smoothing, in conjunction with various operational and environmental factors, to keep supply chain cost under control. This study demonstrated that when capacity tightness is high for the supplier, information sharing plays a more important role in effective supply chain management. In addition, this study also showed that retailers benefit directly from information sharing when advanced forecasting methods are employed under certain conditions.
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Date: December 2009
Creator: Pan, Youqin
Partner: UNT Libraries

The Impact of Legal Sanctions on Recidivism Rates among Male Perpetrators of Domestic Violence

Description: Using a Cox proportional hazards regression model, this dissertation explores three factors currently not addressed in the literature on men who batter women and who are court ordered to participate in a battering intervention program. These factors are the cumulative effects of civil and criminal legal sanctions (dose-response of sanctions) for domestic violence related offenses on recidivism, reduced opportunities to recidivate, and whether the number of legal sanctions imposed has an effect on how long a man maintains his non-recidivism status. Because one domestic violence case may involve multiple sanctions, this study uses the Legal Sanction Dose-Response Index to gauge the cumulative impact of civil and criminal sanctions upon recidivism of domestic violence. The Cox proportional hazards model indicates that the risk of recidivism is 45% lower for men who experienced two legal sanctions (typically arrest and probation) in response to the index case, relative to men who experienced one legal sanction (typically civil protective order). In other words, those with two legal sanctions are able to maintain their non-recidivism status longer relative to those with one sanction. Men with prior criminal court involvement for domestic violence related offenses are more likely to recidivate. Additionally, rather than incarceration reducing opportunities to recidivate, this study finds that incarceration for any offenses committed during the follow-up period is a predictor of recidivism of domestic violence related offenses. It is possible that, rather than incarceration reducing opportunities, recidivists are persistent and use whatever opportunities are available to them to commit domestic violence, despite legal sanctions.
Date: December 2009
Creator: Cosimo, S. Deborah
Partner: UNT Libraries

The Impact of Surveillance Technology on the Behaviors of Municipal Police Departments

Description: Citizen complaints about inappropriate use of force indicate negative police-public relations, unresponsive police services, and the unresponsiveness of police management to citizens' concerns. However, the effective delivery of key policing services depends on the performance of individual police officers. Surveillance technology can monitor and control the behavior of officers, ensuring that police officers provide high quality policing services that meet the needs of citizens. Examples of surveillance technology such as in-car cameras and CCTV can be used as an administrative tool to respond to citizen complaints by police chief executives. This research examines the effect of surveillance technology on the behavior of municipal police departments that is operationalized as the number of citizen complaints that were filed against municipal police departments. This research also examines the impact of surveillance technology on dismissed and sustained complaints by using 511 large municipal police departments in the U.S. from Law Enforcement Management and Administrative Statistics (LEMAS) 2003 dataset. Three different models are developed to evaluate the impact of in-car cameras and CCTV on the citizen complaints and their dispositions. Two ordinary least square regression (OLS) models and a Heckman selection model are used to analyze the data. The Heckman selection model is utilized to correct for selection bias in truncated data for sustained complaints after log transformation. The results suggest that the use of surveillance technology by the police is necessary, but insufficient, in reducing the number of complaints. The finding suggests that videotaped evidence, recorded by surveillance technology, increased the number of convictions of accused officers in municipal police departments. The analysis also suggests that municipal police departments that used CCTV only in 2003 received a higher number of citizen complaints, in comparison to municipal police departments without CCTV, both in 2000 and 2003. No evidence was found to indicate that surveillance ...
Date: December 2009
Creator: Ulkemen, Sinan
Partner: UNT Libraries

In vitro Cultures of Morus alba for Enhancing Production of Phytoestrogens

Description: Plant estrogens have long been associated with health benefits. The potential of tissue culture techniques for the production of several secondary metabolites has been known for many years. Tissue cultures stimulate the production or induce the biosynthesis of novel compounds not found in the mature plant. Tissue culture of Morus alba, family Moraceae, is known to contain phytoestrogens, was established on plant-hormone supplemented Murashige and Skoog (MS) medium. Petiole and the stem tissue from mature trees were the best explants for initiation and proliferation of calli. The best callus proliferation was obtained on MS medium containing 1-napthalene acetic acid (1mg/ml) and benzylaminopurine (0.5mg/ml) for M. alba. Comparison of phytoestrogens of Moraceae species from in vivo and in vitro tissue isolation were carried out. The estrogenic activities of callus extracts were assayed in an estrogen-responsive yeast system expressing the human estrogen receptor alpha. Male callus extracts had higher estrogenic activity than male and female extracts from in vivo and in vitro tissues. Isolation and characterization of phytoestrogens from above tissues were carried out using solid phase extraction, high perfomance liquid chromatography and mass spectrometry techniques. Biochanin A, an isoflavonoid, was isolated as one of the compounds in male callus extracts. Biochanin A has been known to have an antiestrogenic acitivity in mammals. Isoflavonoid compounds have been characterized as strong protein tyrosine kinase inhibitors in variety of animal cells. Isoflavones are structurally similar to estradiol, and display agonistic and antagonistic interactions with the estrogen receptor. Isoflavones possess therapeutic and preventive properties such as being used for postmenopausal osteoporosis, breast cancer, and inhibition of tumors.
Date: December 2009
Creator: Bakshi, Vibhu
Partner: UNT Libraries

Inferring Social and Internal Context Using a Mobile Phone

Description: This dissertation is composed of research studies that contribute to three research areas including social context-aware computing, internal context-aware computing, and human behavioral data mining. In social context-aware computing, four studies are conducted. First, mobile phone user calling behavioral patterns are characterized in forms of randomness level where relationships among them are then identified. Next, a study is conducted to investigate the relationship between the calling behavior and organizational groups. Third, a method is presented to quantitatively define mobile social closeness and social groups, which are then used to identify social group sizes and scaling ratio. Last, based on the mobile social grouping framework, the significant role of social ties in communication patterns is revealed. In internal context-aware computing, two studies are conducted where the notions of internal context are intention and situation. For intentional context, the goal is to sense the intention of the user in placing calls. A model is thus presented for predicting future calls envisaged as a call predicted list (CPL), which makes use of call history to build a probabilistic model of calling behavior. As an incoming call predictor, CPL is a list of numbers/contacts that are the most likely to be the callers within the next hour(s), which is useful for scheduling and daily planning. As an outgoing call predictor, CPL is generated as a list of numbers/contacts that are the most likely to be dialed when the user attempts to make an outgoing call (e.g., by flipping open or unlocking the phone). This feature helps save time from having to search through a lengthy phone book. For situational context, a model is presented for sensing the user's situation (e.g., in a library, driving a car, etc.) based on embedded sensors. The sensed context is then used to switch the phone into a suitable ...
Date: December 2009
Creator: Phithakkitnukoon, Santi
Partner: UNT Libraries

The Influence of Giovanni Bottesini (1821-1889) on Pedro Valls (1869-1935): An Analysis of Homenaje à Bottesini (1906) by Pedro Valls

Description: This document traces a link between Pedro Valls and Giovanni Bottesini by identifying traits of Homenaje à Bottesini that resemble techniques and musical characteristics of Bottesini's music, through the comparison of Valls' Homenaje à Bottesini to Bottesini's Fantasia sur La Sonnambula, focusing on the works formal, musical and idiomatic characteristics. This is supported by documented evidence of Bottesini's presence in Spain during Valls's lifetime and Pedro Valls contact with the Italian master of the double bass school of playing and teaching method. This study also proposes adjustments in the notation of Homenaje à Bottesini to more modern and player-friendly score indications, which will help its inclusion into the active double bass repertoire. This document examines performance practice(s) of the work and what advantages or disadvantages these practices have in playing the work, and to ultimately offer a clear pathway, a road map, to performers interested in delving into Pedro Valls's work, with a better idea of what Valls's style consists of and what approach to take when performing his works.
Date: December 2009
Creator: Amorim, George
Partner: UNT Libraries

Integrating environmental data acquisition and low cost Wi-Fi data communication.

Description: This thesis describes environmental data collection and transmission from the field to a server using Wi-Fi. Also discussed are components, radio wave propagation, received power calculations, and throughput tests. Measured receive power resulted close to calculated and simulated values. Throughput tests resulted satisfactory. The thesis provides detailed systematic procedures for Wi-Fi radio link setup and techniques to optimize the quality of a radio link.
Date: December 2009
Creator: Gurung, Sanjaya
Partner: UNT Libraries

Interactions of equivalence and other behavioral relations: Simple successive discrimination training.

Description: The experimenter asked if documented equivalence class membership would influence the development of shared discriminative stimulus function established through simple successive discrimination training. In Experiment 1, equivalence classes were established with two sets of 9 stimuli. Common stimulus functions were then trained within or across the equivalence classes. Greater acquisition rates of the simple discriminations with stimuli drawn from within the equivalence classes were observed. In Experiment 2, a third stimulus set was added with which no equivalence relations were explicitly trained. The findings of Experiment 1 were replicated, but the Set 3 results were inconsistent across subjects. The outcomes of the two experiments demonstrate that equivalence classes have an effect on other behavioral relations which requires further investigation.
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Date: December 2009
Creator: Brackney, Ryan
Partner: UNT Libraries

Intertextualization: An historical and contextual study of the battle villancico, El más augusto campeón.

Description: This document addresses the cultural and significance of the battle villancico, El más augusto campeón, and its historical, social, and musical contexts within the villancico genre of the Latin American Baroque. This study focuses on the villancico, El más augusto campeón, and explores the possible origins of the text and its relevance to the political and social structure of Cuzco's San Antonio Abad Seminary. Other areas of investigation are the musical analysis of the score and performance practice issues that surface when making choices as a conductor. Considering the seminal position villancicos held in the catechization of the Incans, in part due to their popular nature, the study of a representative example of this significant genre lends further insight into how important the villancico was to the ordinary and feast services of Peruvian (and, by association, Latin American) churches. While within the villancico's textual and musical structure one reads the obvious reflection of peninsular Spanish Catholic culture, its application to the criollo subculture carries an even more striking relevance.
Date: December 2009
Creator: Farris, Daniel
Partner: UNT Libraries

Investigating incidental vocabulary acquisition in ESL conversation classes.

Description: This study examined incidental receptive and productive vocabulary gains within conversation-class interactions. Eleven Mexican learners of English attended four videotaped conversation lessons where 40 target words were incorporated in different types of exposure. Stimulated recall interviews with students highlighted the effect of cognates, learners' access to passive vocabulary, and use of their vocabulary knowledge in learning related words. Posttests revealed a correlation between frequency and receptive/productive gains. Mean scores showed that words mentioned with synonyms were learned most often, followed by task-essential words and last those mentioned without explanation. A two-way ANCOVA revealed main effects for cognates, and a statistical interaction between cognate status and types of exposure. A statistical correlation was found between receptive and productive gains. Aptitude scores correlated with productive gains but not with receptive gains. The results provide implications for ESL teachers who consider incidental learning of vocabulary within their conversation lessons.
Date: December 2009
Creator: Mohamed, Ayman Ahmed Abdelsamie
Partner: UNT Libraries

An investigation into graph isomorphism based zero-knowledge proofs.

Description: Zero-knowledge proofs protocols are effective interactive methods to prove a node's identity without disclosing any additional information other than the veracity of the proof. They are implementable in several ways. In this thesis, I investigate the graph isomorphism based zero-knowledge proofs protocol. My experiments and analyses suggest that graph isomorphism can easily be solved for many types of graphs and hence is not an ideal solution for implementing ZKP.
Date: December 2009
Creator: Ayeh, Eric
Partner: UNT Libraries

An Investigation Into the Factors Leading to the Closure of 40 Private Four-Year Colleges between 1965 and 2005

Description: This study searches for a set of common indicators that contributed to the ultimate closure of 40 colleges and universities between 1965 and 2005. From research on related literature, a set of 31 contributing factors was identified by published experts and observers in higher education. That set of indicators was then used as a list of 31 questions answered by data found in newspaper articles, professional journals, published research work, published institutional records, data taken from the Department of Education, data taken from IPEDS, data published in historical recounts of the colleges of interest, etc. The data was accumulated in the form of yes/no responses to the 31 questions. Although the study involved only 40 colleges and universities this population represents the majority of institutions that pass the restrictions of limitations and delimitations described in the full document. The complete data set was processed using SPSS which produced ANOVA tables and level of statistical significance for each indicator question. The results indicate that out of the 31 original indicator questions there were two groups of statistically significant indicators. The larger group of indicators having statistical significance at the .05 level encompassed the smaller group having statistical significance at the .001 level. There were ten indicators in the first group with significance at the .05 level and seven in the second group with significance at the .001 level. Both groups conform to Bowen's revenue theory of cost associated with the operations of colleges and universities. The first group also has a cultural values component observed by a number of the experts cited in this study. The second is very tightly associated with Bowen's revenue theory of cost and Bates and Santerre's for profit theory of economics. Future research needs to be done to investigate the effect of such use of those ...
Date: December 2009
Creator: Province, Terry Paul
Partner: UNT Libraries

Investigation of cryopreservation methods for adherent nerve cell networks in vitro.

Description: Cryopreservation in suspension is commonplace for a variety of cell types. However, cryopreservation of adherent cells has achieved limited success. This research aimed to cryopreserve adherent nerve cell networks in vitro in a manner that preserved network morphology and physiology. Successful implementation would enable long term storage of adherent neuronal networks on microelectrode arrays and on-demand access for use in pharmacological and toxicological testing. Based upon morphological assessments, excellent post-thaw preservation was obtained and post-thaw cultures survived in a transitional medium for up to 3.5 hours. However, transitions to native culture medium post-thaw presented difficulties, ultimately resulting in necrosis. A discussion of methods to supplement the current research and increase post-thaw viability is included in the thesis.
Date: December 2009
Creator: Webb, Veronica Fine
Partner: UNT Libraries

Latent Transition Analysis of Pre-service Teachers' Efficacy in Mathematics and Science

Description: This study modeled changes in pre-service teacher efficacy in mathematics and science over the course of the final year of teacher preparation using latent transition analysis (LTA), a longitudinal form of analysis that builds on two modeling traditions (latent class analysis (LCA) and auto-regressive modeling). Data were collected using the STEBI-B, MTEBI-r, and the ABNTMS instruments. The findings suggest that LTA is a viable technique for use in teacher efficacy research. Teacher efficacy is modeled as a construct with two dimensions: personal teaching efficacy (PTE) and outcome expectancy (OE). Findings suggest that the mathematics and science teaching efficacy (PTE) of pre-service teachers is a multi-class phenomena. The analyses revealed a four-class model of PTE at the beginning and end of the final year of teacher training. Results indicate that when pre-service teachers transition between classes, they tend to move from a lower efficacy class into a higher efficacy class. In addition, the findings suggest that time-varying variables (attitudes and beliefs) and time-invariant variables (previous coursework, previous experiences, and teacher perceptions) are statistically significant predictors of efficacy class membership. Further, analyses suggest that the measures used to assess outcome expectancy are not suitable for LCA and LTA procedures.
Date: December 2009
Creator: Ward, Elizabeth Kennedy
Partner: UNT Libraries

Laying the foundation for successful non-academic writing: Professional communication principles in the K-5 curricula of the McKinney Independent School District.

Description: Traditionally, K-5 students' writing has had a primarily academic aim-to help students master concepts and express themselves. Even if students take a professional writing course later, they typically do not have the opportunity to practice-over the long period of time mastery requires-the non-academic writing skills they will be required to use as part of their jobs and in their civic life. Based on a limited K-5 study, Texas' McKinney Independent School District is doing a good job of preparing students at the elementary-school level in the areas of collaboration and presentation. A fair job of helping elementary-school students understand the communication situation, define audience, clarify purpose, gather and evaluate resources, and test usability. [And] a poor job of helping elementary-school students with analysis and organization. With their teachers' help, K-5 students eventually grasp the communication situation and can broadly identify their audience and purpose, but they do not appear to select words, format, communication style, or design based on that audience and purpose. Their writer-based focus affects their presentations as well, although they do present frequently. If teachers routinely incorporated audience and purpose considerations into every aspect of communication assignments (format, communication style, design), students would be better prepared for non-academic communication. Texas pre-service teachers practice the types of documents they will write on the job but do not receive training in design or style. Likewise, they practice researching, collaborating, and presenting but receive little training in those skills. If Texas K-5 teachers are to supplement the curriculum with professional writing principles, as trends suggest they should, education programs need to focus on these principles in their pre-service teacher curriculum. Professional writing principles need to become part of ingrained writing patterns because these are the skills that will best serve students after they graduate, both in their careers and civic ...
Date: December 2009
Creator: Treviño, Marlea
Partner: UNT Libraries

Letters, Liberty, and the Democratic Age in the Thought of Alexis de Tocqueville

Description: When Alexis de Tocqueville observed the spread of modern democracy across France, England, and the United States, he saw that democracy would give rise to a new state of letters, and that this new state of letters would influence how democratic citizens and statesmen would understand the new political world. As he reflected on this new intellectual sphere, Tocqueville became concerned that democracy would foster changes in language and thought that would stifle concepts and ideas essential to the preservation of intellectual and political liberty. In an effort to direct, refine, and reshape political thought in democracy, Tocqueville undertook a critique of the democratic state of letters, assessing intellectual life and contributing his own ideas and concepts to help citizens and statesmen think more coherently about democratic politics. Here, I analyze Tocqueville's critique and offer an account of his effort to reshape democratic political thought. I show that through his analyses of the role of intellectuals in democratic regimes, the influence of modern science on democratic public life, the intellectual habits that democracy fosters, and the power of literary works for shaping democratic self-understanding, Tocqueville succeeds in reshaping democratic language and thought in a manner that contributes to the preservation of intellectual and political liberty within the modern democratic world.
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Date: December 2009
Creator: Elliot, Natalie J.
Partner: UNT Libraries

Level Curves of the Angle Function of a Positive Definite Symmetric Matrix

Description: Given a real N by N matrix A, write p(A) for the maximum angle by which A rotates any unit vector. Suppose that A and B are positive definite symmetric (PDS) N by N matrices. Then their Jordan product {A, B} := AB + BA is also symmetric, but not necessarily positive definite. If p(A) + p(B) is obtuse, then there exists a special orthogonal matrix S such that {A, SBS^(-1)} is indefinite. Of course, if A and B commute, then {A, B} is positive definite. Our work grows from the following question: if A and B are commuting positive definite symmetric matrices such that p(A) + p(B) is obtuse, what is the minimal p(S) such that {A, SBS^(-1)} indefinite? In this dissertation we will describe the level curves of the angle function mapping a unit vector x to the angle between x and Ax for a 3 by 3 PDS matrix A, and discuss their interaction with those of a second such matrix.
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Date: December 2009
Creator: Bajracharya, Neeraj
Partner: UNT Libraries

The List

Description: The List is a collection of short stories focusing on the inability to adapt, or learn from self-destructive patterns, and the bizarre ways people reach out for one another when they don't know what else to do.
Date: December 2009
Creator: O'Brien, Tanner Chase
Partner: UNT Libraries

A Longitudinal Examination of Factors Associated with Custodial Grandparenting: A Test of Moderated Mediation

Description: The purpose of this study was to explore the following relationships: (a) how moderating factors (gender, age, ethnicity, social support, marital status, reason for role assumption and number of grandchildren in the home) can influence the mediating role of resiliency, and (b) how resiliency may mediate the negative effects of raising grandchildren (role demands, life disruptions, and difficulties with grandchildren) on grandparent adjustment over time. Resiliency was hypothesized to have the greatest effect on custodial grandparents who experienced the most stress (i.e., older, single, Caucasian males lacking social support and raising more than one grandchild). Mediation was assessed using structural equation modeling. Results indicated resilience mediated the relationship between role assumptions (i.e., role demands and life disruptions) and grandparent adjustment; however, resilience did not mediate the relationship between grandchild characteristics and grandparent adjustment. Due to the small number of custodial grandfathers (n = 14), non-married grandparents (n = 29), non-Caucasian grandparents (n = 10), the small number of grandparents who assumed the custodial role for less ambiguous reasons (n = 24), and the number of custodial grandparents with more than one grandchild residing in the home (n = 29) participating within the study, hierarchical multiple regressions were only conducted to test for moderated mediation for perceived social support and the age of the grandparent. Results indicated resilience mediates the relationship between life disruption and grandparent well-being for younger custodial grandparents and for custodial grandparents with perceived high social support.
Date: December 2009
Creator: Moske, Amanda Kay
Partner: UNT Libraries

The Map and the Territory in the Poetry of Wallace Stevens

Description: In this dissertation, Wallace Stevens' imagination-reality problem as depicted in his poetry is discussed in terms of an eco-critical map-territory divide. Stevens's metaphor of "the necessary angel" acts to mediate human necessity, the map, with natural necessity, the territory, in order to retain contact with changing cultural and environmental conditions. At stake in this mediation are individual freedom and the pertinence of the imagination to the experience of reality. In Chapter 2, the attempt at reconciliation of these two necessities will be described in terms of surrealism. Stevens's particular approach to surrealism emphasizes separating and delineating natural necessity from human necessity so that through the poem the reader can experience the miracle of their reconciliation. In Chapter 3, this delineation of the two necessities, map and territory, will be examined against Modernist "decreation," which is the stripping bare of human perception for the purpose of regaining glimpses of the first idea of the external world. And in Chapter 4, Stevens's approach to the problem of the map-territory divide will be considered against his alienation or internal exile: balancing nature and identity through mediating fictions results in a compromised approach to the marriage of mind and culture in a historically situated place.
Date: December 2009
Creator: Thompson, Erik Robb
Partner: UNT Libraries

Metabolic, cardiac and ventilatory regulation in early larvae of the South African clawed frog, Xenopus laevis.

Description: Early development of O2 chemoreception and hypoxic responses under normoxic (150 mmHg) and chronically hypoxic (110 mmHg) conditions were investigated in Xenopus laevis from hatching to 3 weeks post fertilization. Development, growth, O2 consumption, ventilatory and cardiac performance, and branchial neuroepithelial cells (NEC) density and size were determined. At 3 days post fertilization (dpf), larvae started gill ventilation at a rate of 28 ± 4 beats/min and showed increased frequency to 60 ± 2 beats/min at a PO2 of 30 mmHg. Also at 3 dpf, NECs were identified in the gill filament buds using immunohistochemical methods. Lung ventilation began at 5 dpf and exhibited a 3-fold increase in frequency from normoxia to a PO2 of 30 mmHg. Hypoxic tachycardia developed at 5 dpf, causing an increase of 20 beats/min in heart rate, which led to a 2-fold increase in mass-specific cardiac output at a PO2 of 70 mmHg. At 10 dpf, gill ventilatory sensitivity to hypoxia increased, which was associated with the increase in NEC density, from 15 ± 1 to 29 ± 2 cells/mm of filament at 5 and 10 dpf, respectively. Unlike the elevated rate, cardiac and ventilatory volumes were independent of acute hypoxia. Despite increased cardioventilatory frequency, larvae experienced an average of 80% depression in during acute hypoxia. Chronic hypoxia (PO2 of 110 mmHg) decreased mass-specific cardiac performance before 10 dpf. In older larvae (10 to 21 dpf), chronic hypoxia decreased acute branchial and pulmonary hypoxic hyperventilation and increased NEC size. Collectively, these data suggest that larvae exhibit strong O2-driven acute hypoxic responses post-hatching, yet are still O2 conformers. All acute hypoxic responses developed before 5 dpf, and then the effects of chronic hypoxia started to show between 7 and 21 dpf. Thus, the early formation of acute hypoxic responses is susceptible to the environment and can ...
Date: December 2009
Creator: Pan, Tien-Chien
Partner: UNT Libraries

Moderators of the sociocultural internalization-body dissatisfaction relationship among female undergraduates.

Description: The sociocultural model of eating pathology is an empirically-supported model explaining eating disorder etiology. The model poses that body dissatisfaction and subsequent eating pathology stems from the unrealistic standards formulated by Westernized society. Although the model has strong empirical support, variables within the model do not account for 100% of the variance in disordered eating. Thus, the current researcher attempted to explore potential moderating factors in the sociocultural model of eating disorders that may help to explain variance currently unaccounted for. In particular, the researcher focused on the relationship between sociocultural internalization and body dissatisfaction, given that this relationship has not been previously explored within the literature. Based on theoretical support, the researcher chose several potential variables to test, including perfectionism, neuroticism, body surveillance, and shame. Primary analyses tested each variable for moderating effects using hierarchical moderated regression, but no significant findings were shown. Results of post hoc analyses showed all variables had significant mediating effects, with the exception of self-oriented perfectionism. The discussion section addresses consistency with previous research, limitations of the present study, treatment implications and guidelines for future research.
Date: December 2009
Creator: Latimer-Kern, Kelsey M.
Partner: UNT Libraries