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Finding Meaning in Context Using Graph Algorithms in Mono- and Cross-lingual Settings (open access)

Finding Meaning in Context Using Graph Algorithms in Mono- and Cross-lingual Settings

Making computers automatically find the appropriate meaning of words in context is an interesting problem that has proven to be one of the most challenging tasks in natural language processing (NLP). Widespread potential applications of a possible solution to the problem could be envisaged in several NLP tasks such as text simplification, language learning, machine translation, query expansion, information retrieval and text summarization. Ambiguity of words has always been a challenge in these applications, and the traditional endeavor to solve the problem of this ambiguity, namely doing word sense disambiguation using resources like WordNet, has been fraught with debate about the feasibility of the granularity that exists in WordNet senses. The recent trend has therefore been to move away from enforcing any given lexical resource upon automated systems from which to pick potential candidate senses,and to instead encourage them to pick and choose their own resources. Given a sentence with a target ambiguous word, an alternative solution consists of picking potential candidate substitutes for the target, filtering the list of the candidates to a much shorter list using various heuristics, and trying to match these system predictions against a human generated gold standard, with a view to ensuring that the …
Date: May 2013
Creator: Sinha, Ravi Som
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Bioconcentration and Morphological Effects of Triclosan on Three Species of Wetland Plants (open access)

Bioconcentration and Morphological Effects of Triclosan on Three Species of Wetland Plants

Triclosan (TCS) is an antimicrobial compound found in several types of common household products. After being washed down the drain, TCS will then end up in the local watershed. Although numerous studies have been conducted to evaluate the fate and effects of TCS in aquatic environments, there have been no studies evaluating the role arbuscular mycorrhizal fungi (AM) play in a plants response to TCS exposure. Three species of wetland plants native North Texas were inoculated with AM spores and exposed to 0, 0.4 g/L and 4.0 g/L TCS concentrations. Root morphology of E. prostrata and S. herbacea showed AM and exposure responses. S. herbacea produced the greatest amounts biomass and TCS bioaccumulation, in all but one treatment. It also displayed opposing results to E. prostrata in measures of root length, root surface area, relative root mass, relative shoot mass and shoot:root ratio. TCS root tissue concentrations increased with increased exposures for both E. prostrata and S. herbacea. Even though E. prostrata had the lowest levels in each measure of biomass production, it had the highest amount of root TCS bioaccumulation in the AM inoculated 4.0 g/L treatment. H. laevis was between the other two species in terms of biomass …
Date: May 2013
Creator: Smith, Caleb M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Modern Api Design and Physical Computing Techniques in Just Intonation Performance Practice (open access)

Modern Api Design and Physical Computing Techniques in Just Intonation Performance Practice

approached previously by both Harry Partch and Ben Johnston, and proposes the decoupling of interface and sound production as a way forward. The design and implementation of a software instrument and a hardware prototype are described, both using a simple API for variable tuning instruments. The hardware prototype uses physical computing techniques to control the tuning of a string with a servo motor, while the software instrument exists entirely in a web browser. Finally, potential algorithms for clients of the API are presented, and the effectiveness of the hardware prototype is evaluated by measuring its pitch accuracy.
Date: May 2013
Creator: Sonnabaum, Mark
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Beliefs and Expectations of Effective Secondary Choral Teachers in Culturally Diverse Schools (open access)

The Beliefs and Expectations of Effective Secondary Choral Teachers in Culturally Diverse Schools

Through the years, educational theorists and researchers have been interested in a possible relationship between teachers' effectiveness and their beliefs and expectations. Three concepts underpinned this work: teacher effectiveness, cultural diversity, and teachers' beliefs and expectations. The premise of the study was that the beliefs and expectations of effective secondary choral teachers are related to the social-cultural contexts in which they teach. The study implemented critical discourse analysis as the theoretical framework and the in-depth phenomenological long interview for data collection. Three secondary choral teachers were selected to participate in the study based on the researcher's criteria. The study revealed how each teacher conceptualized student cultural diversity during the teaching experience. Teacher beliefs about effective teaching in culturally diverse settings were described as developing over time in phases along a continuum. The study also confirmed that teachers' beliefs about students can be changed through experiences and reflection. The study revealed effective teachers focused on three different types of expectations in the teaching and learning context and affirmed diverse cultural identities and backgrounds. Recommendations included the development of stronger mentorship programs to increase effective teaching strategies for the secondary choral classroom. The findings of this study support my previous work, which …
Date: May 2013
Creator: Spradley, Mackie V.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Federal Funds Target Rate Surprise and Equity Duration (open access)

Federal Funds Target Rate Surprise and Equity Duration

In this paper I use an equity duration framework to develop and empirically test the hypothesis that returns on growth stock portfolios react more strongly to Federal Funds target rate change announcements, as compared to value stock portfolios. When I decompose the Federal Funds rate change, I find that portfolio returns are only sensitive to rate shocks, as opposed to the predictable component of rate change. Since growth stocks are expected to have higher duration than value stocks, I further explore the well documented polarity between value and growth stocks, by examining the interest rate sensitivities of portfolios that diverge along four fundamental-to-prices ratios: dividend yield, book-to-market value, earnings-to-price and cashflows-to-price. In each case, I find that price reactions are more pronounced for portfolios with high growth characteristics. I also document that portfolio returns react asymmetrically to positive and negative target rate surprises, and that this reaction is conditional on the state of business cycles - periods of economic expansions and recessions. To improve the robustness of my results, several statistical applications have been applied. First, I include Newey-west estimators to examine significant levels of regression estimates. Second, I check if there is any contemporaneous correlation across target rate shocks …
Date: May 2013
Creator: Tee, Kienpin
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Politics of Grading: a Comparative Study of High School English Teachers' Personal Beliefs, Self-reported Systems, and Actual Practices (open access)

The Politics of Grading: a Comparative Study of High School English Teachers' Personal Beliefs, Self-reported Systems, and Actual Practices

The purpose of this study was to attain and analyze data regarding high school English teachers' beliefs about grading practices and their self-reported grading practices, to identify and understand disparities that exist between teachers' beliefs and self-reported practices, to identify discrepancies between the same self-reported practices and evidence of the practices actually utilized, and to consider teachers' perceptions as to the causes for these discrepancies. Instrumentation for this study included two surveys with both Likert and Likert-like items and an interview/portfolio analysis of teachers' grading systems. A combined total of 204 high school English-language arts teachers representing thirty-eight states and eighty-five schools comprised the sample. Corresponding pairs of Likert-type items were analyzed using studies of the mode, median, mean rank, and the Mann-Whitney U Test to study a comparison of the medians, and comparisons of true Likert scale item results were completed using studies of the means and an independent samples t-test. Interview/portfolio analysis data were analyzed both descriptively and inferentially including the calculation of 95% confidence intervals for generalizability. All open-ended items were considered qualitatively through a process of identifying and categorizing trends in language and over-arching themes. Results indicate that the sample finds grading practices recommended by experts …
Date: May 2013
Creator: Thibodeaux, Lisa M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Estimation of Aircraft Emissions for the Corpus Christi International Airport, Corpus Christi, Texas (open access)

Estimation of Aircraft Emissions for the Corpus Christi International Airport, Corpus Christi, Texas

Commercial aviation is a vital part of the United States economy. It generates over $1 trillion annually, which is more than 5% of the U.S. GDP, and produces approximately 10 million jobs. Every year there is an increase in commercial air traffic. This is attributed to expanding trade between states and other countries, which requires larger amounts of cargo aircraft in operation, and also catering to the growing number of middle and upper class passengers who travel for business and pleasure purposes. A rise in commercial aviation leads to the use of more aviation fuel on a monthly and annual basis. This in turn leads to escalated levels of combustion by-products from jet and turbofan engines into the atmosphere. The negative effects of these by-products range from producing poor air quality and consequent health hazards to contributing to global warming. This study is aimed at assessing the impacts of aircraft emissions on the local air quality in Corpus Christi using the Emissions and Dispersion Modeling System. Flight data for the study was obtained from the Department of Transportation's Research and Innovative Technology Administration. Analyses of the emissions were compared on monthly, annual, engine type and airline provider bases. Climatic, economic …
Date: May 2013
Creator: Thomas, Gregson Johann
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Ways of Reflection: Heidegger, Science, Reflection, and Critical Interdisciplinarity (open access)

The Ways of Reflection: Heidegger, Science, Reflection, and Critical Interdisciplinarity

This thesis argues that there is a philosophical attempt directed at combating the fragmentation of the sciences that starts with Heidegger and continues today through Trish Glazebrook's interpretations of the former's concept of "reflection," and Carl Mitcham and Robert Frodeman's concept of "critical interdisciplinarity" (CID). This is important as the sciences are both more implicated in our lives and more fragmented than ever. While scientific knowledge is pursued for its own sake, the pertinent facts, meaning, and application of the science is ignored. By linking Heidegger's views on the fragmentation of the sciences to Glazebrook's interpretations of reflection and Mitcham and Frodeman's CID, I show that CID is a concrete realization of Heidegger's reflection.
Date: May 2013
Creator: Toole, Toby Houston
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Online Lecture As an Alternative Method of Instruction in College Classrooms: Measuring the Effects of Alternating In-class with Online Lectures in Two Sections of an Undergraduate Introduction to Behavior Analysis Course (open access)

Online Lecture As an Alternative Method of Instruction in College Classrooms: Measuring the Effects of Alternating In-class with Online Lectures in Two Sections of an Undergraduate Introduction to Behavior Analysis Course

Online instruction is becoming increasingly common at universities; however, there is little single subject research concerning the effectiveness of the online lecture format. We investigated whether online lecture could replace in-class lecture in two sections of an undergraduate Introduction to Behavior Analysis course without detrimentally affecting student learning. Using an adapted alternating treatments design, online and in-class lecture formats were counterbalanced across the two course sections. Experimenters collected data on lecture attendance/access, percent correct on the weekly quiz, and student report on lecture format preference. The data show that, within the context of this class, students performed equally in the weekly quiz regardless of lecture format; further, that this is consistent when looking at individual student data and mean data. However, although students stated a preference for online lecture in the questionnaire, a greater percentage of students attended in-class lecture than accessed online lecture.
Date: May 2013
Creator: Treacher, Kay G.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Zinc Oxide Nanoparticles for Nonlinear Bioimaging, Cell Detection and Selective Cell Destruction (open access)

Zinc Oxide Nanoparticles for Nonlinear Bioimaging, Cell Detection and Selective Cell Destruction

Light matter interactions have led to a great part of our current understanding of the universe. When light interacts with matter it affects the properties of both the light and the matter. Visible light, being in the region that the human eye can "see," was one of the first natural phenomenon we used to learn about our universe. The application of fundamental physics research has spilled over into other fields that were traditionally separated from physics, being considered two different sciences. Current physics research has applications in all scientific fields. By taking a more physical approach to problems in fields such as chemistry and biology, we have furthered our knowledge of both. Nanocrystals have many interesting optical properties. Furthermore, the size and properties of nanocrystals has given them applications in materials ranging from solar cells to sunscreens. By understanding and controlling their interactions with systems we can utilize them to increase our knowledge in other fields of science, such as biology. Nanocrystals exhibit optical properties superior to currently used fluorescent dyes. By replacing molecular dyes with nanoparticles we can reduce toxicity, increase resolution and have better cellular targeting abilities. They have also shown to have toxicity to cancer and antibacterial …
Date: May 2013
Creator: Urban, Ben E.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Fortification Renaissance: the Roman Origins of the Trace Italienne (open access)

Fortification Renaissance: the Roman Origins of the Trace Italienne

The Military Revolution thesis posited by Michael Roberts and expanded upon by Geoffrey Parker places the trace italienne style of fortification of the early modern period as something that is a novel creation, borne out of the minds of Renaissance geniuses. Research shows, however, that the key component of the trace italienne, the angled bastion, has its roots in Greek and Roman writing, and in extant constructions by Roman and Byzantine engineers. The angled bastion of the trace italienne was yet another aspect of the resurgent Greek and Roman culture characteristic of the Renaissance along with the traditions of medicine, mathematics, and science. The writings of the ancients were bolstered by physical examples located in important trading and pilgrimage routes. Furthermore, the geometric layout of the trace italienne stems from Ottoman fortifications that preceded it by at least two hundred years. The Renaissance geniuses combined ancient bastion designs with eastern geometry to match a burgeoning threat in the rising power of the siege cannon.
Date: May 2013
Creator: Vigus, Robert T.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Influence of Business Intelligence Components on the Quality of Decision Making (open access)

The Influence of Business Intelligence Components on the Quality of Decision Making

Decision makers require the right information at the right time, in the right place and in the right format so that they can make good decisions. Although business intelligence (BI) has the potential to improve decision making, there is little empirical evidence of how well this has been achieved. The purpose of this dissertation is to examine the quality of decisions made using BI. The research question it addresses is what are the key antecedents of decision quality for users of business intelligence systems? The theoretical support for the model is developed based on the literature review that draws on decision support systems (DSS), group decision support systems (GDSS), and BI. Grounded on this literature review, the antecedents of decision quality are operationalized in this dissertation through independent variables such as the problem space complexity, the level of BI usage, the BI user experience, and information quality. The dependent variable is operationalized as decision quality and it captures the self-satisfaction with a decision made by users in a BI environment. The research model was tested using a survey of BI users whose names were provided by a marketing company. This research suggests that BI user experience is a more complex …
Date: May 2013
Creator: Visinescu, Lucian L.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Determinacy-related Consequences on Limit Superiors (open access)

Determinacy-related Consequences on Limit Superiors

Laczkovich proved from ZF that, given a countable sequence of Borel sets on a perfect Polish space, if the limit superior along every subsequence was uncountable, then there was a particular subsequence whose intersection actually contained a perfect subset. Komjath later expanded the result to hold for analytic sets. In this paper, by adding AD and sometimes V=L(R) to our assumptions, we will extend the result further. This generalization will include the increasing of the length of the sequence to certain uncountable regular cardinals as well as removing any descriptive requirements on the sets.
Date: May 2013
Creator: Walker, Daniel
Object Type: Thesis or Dissertation
System: The UNT Digital Library
James Wintle's Northwest Miniatures for Flute, Trumpet and Piano (1998): a Performance Guide (open access)

James Wintle's Northwest Miniatures for Flute, Trumpet and Piano (1998): a Performance Guide

James Wintle's, Northwest Miniatures for flute, trumpet and piano is a unique work in the chamber music repertoire. In addition, the use of auxiliary instruments makes this piece a rarity in the flute and trumpet chamber music repertoire. There are a limited number of resources presently available to performers regarding Northwest Miniatures.This dissertation provides a pedagogical performance guide addressing the inherent challenges for the flutist and this instrumentation and serves as a new resource for performers and scholars of this work. It provides a performance analysis of the piece along with pertinent pedagogical information and exercises to assist the flutist. Insight from the composer on how to address these challenges is also included. Because there are a limited number of scholarly resources available on the subject of flute and trumpet chamber music, this dissertation is a significant contribution to this genre of repertoire.
Date: May 2013
Creator: Walker, Julee Kim
Object Type: Thesis or Dissertation
System: The UNT Digital Library
My Crown Is in My Heart, Not on My Head: Heart Burial in England, France, and the Holy Roman Empire From Medieval Times to the Present (open access)

My Crown Is in My Heart, Not on My Head: Heart Burial in England, France, and the Holy Roman Empire From Medieval Times to the Present

Heart burial is a funerary practice that has been performed since the early medieval period. However, relatively little scholarship has been published on it in English. Heart burial began as a pragmatic way to preserve a body, but it became a meaningful tradition in Western Europe during the medieval and early modern periods. In an anthropological context, the ritual served the needs of elites and the societies they governed. Elites used heart burial not only to preserve their bodies, but to express devotion, stabilize the social order and advocate legitimacy, and even gain heaven. Heart burial assisted in the elite Christian, his or her family, and society pass through the liminal period of death. Over the centuries, heart burial evolved to remain relevant. The practice is extant to the present day, though the motivations behind it are very different from those of the medieval and early modern periods.
Date: May 2013
Creator: Duch, Anna M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Oral Syringe Training Animals: Indiscriminable and Discriminable Punishment Contingencies (open access)

Oral Syringe Training Animals: Indiscriminable and Discriminable Punishment Contingencies

Animals are commonly trained to perform behaviors during routine husbandry procedures. However, some husbandry procedures have aversive consequences when the real procedure is performed. This commonly results in loss of the trained behavior. The present study assessed whether maintaining the antecedent environmental stimulus conditions between appetitive and aversive outcomes would prevent this effect and, conversely, whether adding a stimulus discrepancy would facilitate this effect. Three domestic rats served as participants in a multiple baseline across participants design with multi-element components. All three rats stopped performing a trained behavior when a discrepant stimulus reliably predicted an aversive outcome. In addition, all three rats continued to perform the same behavior when antecedent environmental stimulus conditions were consistent between aversive and appetitive outcomes. Results are discussed in terms of practical implications for behavior change agents and conceptual implications for learning theory.
Date: May 2013
Creator: Erickson, Emilie Jane
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Determinants of the Applications to the Institutional Care in Turkey: Darulaceze Example (open access)

Determinants of the Applications to the Institutional Care in Turkey: Darulaceze Example

Although institutional care has started to be outmoded in the developed countries with development of different models of care, it still has a considerable place in the developing countries such as Turkey. This is because, changes in the demographic structure, extended family, and urban development of Turkey has brought about several aging problems leading older adults to end up in institutions. Loneliness was one of the significant reasons given in the Social Inquiry Survey of Applicants of Darulaceze Old-Age Institution and the basis for a micro level analysis in this study. Therefore, the main objective of the study was to determine the predictors of loneliness, including age, the state of living alone, functional independence, education, and gender. Analysis of the results indicated that these predictors have significant effects on the loneliness predominantly defined by social factors rather than medical factors. In addition, the meso and macro level analyses were employed to control the micro level analysis and see a general picture of institutional care. Thus, an academic example of diagnosing the main reasons behind the institutional care was presented to understand the context of aging in Turkey.
Date: May 2013
Creator: Esendemir, Serif
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Transfantasies for Flauto Traverso, Computer Music, and Dance (open access)

Transfantasies for Flauto Traverso, Computer Music, and Dance

TransFantasies is an interdisciplinary composition for Baroque flute (flauto traverso), computer music, and dance. A crucial component of the work is an interactive hardware and software environment that provides the opportunity for the players to shape aspects of the work during the performance. This essay discusses the influences that inspired the work and presents an in-depth analysis of notable elements of the composition. Primary issues include compositional models for gesture-based composition, historical performance practices, interactivity, and relationships between music and dance. The final component of the essay details the software component designed to create the composition. It also discusses music technology in current practice and its role in this particular work. At its core, TransFantasies is concerned with those moments where computer-influenced decisions and human behaviors collide.
Date: May 2013
Creator: Fick, Jason
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Modeling Transition Metal Catalysts for Small Molecule Activation and Functionalization (open access)

Modeling Transition Metal Catalysts for Small Molecule Activation and Functionalization

There is a high demand for the development of processes for the conversion of ubiquitous molecules into industrially useful commodities. Transition metal catalysts are often utilized for the activation and functionalization of small organic molecules due to their diverse nature and proven utility with a myriad of chemical transformations. The functionalization of methane (CH4) and dinitrogen (N2) to methanol (CH3OH) and ammonia (NH3) respectively is of particular interest; however, both methane and dinitrogen are essentially inert due to the inherit strength of their bonds. In this dissertation a series of computational studies is performed to better understand the fundamental chemistry behind the functionalization of methane and the activation of dinitrogen in a homogeneous environment. A catalytic cycle is proposed for the oxy-functionalization of methane to methanol. The cycle consists of two key steps: (1) C-H activation across a metal-alkoxide bond (M-OR), and (2) regeneration of the M-OR species through an oxy-insertion step utilizing external oxidants. The C-H activation step has been extensively studied; however, the latter step is not as well understood with limited examples. For this work, we focus on the oxy-insertion step starting with a class of compounds known to do C-H activation (i.e., Pt(II) systems). Computational studies …
Date: May 2013
Creator: Figg, Travis M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Exploring the Evolutionary History of North American Prairie Grouse (Genus: Tympanuchus) Using Multi-locus Coalescent Analyses (open access)

Exploring the Evolutionary History of North American Prairie Grouse (Genus: Tympanuchus) Using Multi-locus Coalescent Analyses

Conservation biologists are increasingly using phylogenetics as a tool to understand evolutionary relationships and taxonomic classification. The taxonomy of North American prairie grouse (sharp-tailed grouse, T. phasianellus; lesser prairie-chicken, T. pallidicinctus; greater prairie-chicken, T. cupido; including multiple subspecies) has been designated based on physical characteristics, geography, and behavior. However, previous studies have been inconclusive in determining the evolutionary history of prairie grouse based on genetic data. Therefore, additional research investigating the evolutionary history of prairie grouse is warranted. In this study, ten loci (including mitochondrial, autosomal, and Z-linked markers) were sequenced across multiple populations of prairie grouse, and both traditional and coalescent-based phylogenetic analyses were used to address the evolutionary history of this genus. Results from this study indicate that North American prairie grouse diverged in the last 200,000 years, with species-level taxa forming well-supported monophyletic clades in species tree analyses. With these results, managers of the critically endangered Attwater's prairie-chicken (T. c. attwateri) can better evaluate whether outcrossing Attwater's with greater prairie-chickens would be a viable management tool for Attwater's conservation.
Date: May 2013
Creator: Galla, Stephanie J.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Is There Justice in Mercy?  the Retributive Philosophies of Executive Clemency (open access)

Is There Justice in Mercy? the Retributive Philosophies of Executive Clemency

Executive clemency is assumed to be a mechanism to correct miscarriages of justice brought about by the criminal justice system, yet little empirical research exists to confirm this assumption. This research study examined the types of rationales cited in 799 cases of executive clemency from six states from 2005 to 2012. Rationales based upon retributive philosophies, in which a miscarriage of justice was cited, were further analyzed. This analysis revealed that only seven percent of all clemency decisions from the examined states cited retributive rationales. Of the fifty-six grants of clemency that cited retributive rationales, most were granted in the forms of pardons. The analysis indicated that executive clemency is utilized as a mechanism to correct injustices, specifically in cases of innocence. This study concludes with a discussion of policy implications and the reliance on executive clemency as a fail-safe to the criminal justice system.
Date: May 2013
Creator: Gibbs, Gina N.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Blood and Earth: Indivisible Territory and Terrorist Group Longevity (open access)

Blood and Earth: Indivisible Territory and Terrorist Group Longevity

The study of terrorism has been both broad in scope and varied in approach. Little work has been done, however, on the territorial aspects of terrorist groups. Most terrorist groups are revolutionary to one degree or another, seeking the control of a piece of territory; but for the supportive population of a terrorist group, how important is the issue of territory? Are the intangible qualities of territory more salient to a given population than other factors? Are territorially based terrorist groups more durable than their ideologically or religiously motivated cohorts? This paper aims to propose the validity of the territorial argument for the study of political terrorism.
Date: May 2013
Creator: Glass, Richard A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Home Literacy Practices in Diverse Families: Parental Involvement in Kindergarten Children's Literacy Development (open access)

Home Literacy Practices in Diverse Families: Parental Involvement in Kindergarten Children's Literacy Development

Although prior research has shown that parental involvement positively affects a child's literacy development, attention should also be directed to the factors that keep parents from being involved in their children's education. The study reported in this dissertation examined five factors: socioeconomic status, level of education, employment, culture, and language that may be influential in parental assistance of their children's literacy development in the home. The data sources for this investigation included interview responses and a demographic survey. Data from 17 parents, each from a different household, and each with a child in kindergarten were obtained and used for the study. For analyses of these data, content analysis was used to identify similar themes among the interview responses and the demographic survey. Results indicated the following: (1) the time parents spent assisting their child with literacy activities was affected by long work hours, (2) parents with a yearly income of $25,000 or less were unable to provide additional literacy materials for their children, (3) lack of multicultural literature caused culturally diverse parents to feel devalued, and (4) parents who did not speak English fluently lacked the strategies to assist their children in completing English literacy homework. The findings suggest there …
Date: May 2013
Creator: Gonzalez, Lauren
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Aging Is a Determinant in Anoxia Stress Tolerance in Caenorhabditis Elegans (open access)

Aging Is a Determinant in Anoxia Stress Tolerance in Caenorhabditis Elegans

Oxygen availability is critical for survival for most organisms. The nematode, C. elegans, has been useful for studying genetic regulation of anoxia tolerance due to the oxygen deprivation response mechanisms shared with other metazoans. Studies examining long-term anoxia (72h, LTA) tolerance have only been conducted at adult day 1. To investigate the effect of aging on anoxia tolerance wild-type and mutant strains were exposed to LTA between adult day 1 and day 9. Wild-type isolates and daf-16(mu86) (FOXO transcription factor regulated by insulin-signaling) and aak-2(gt33) (catalytic subunit of AMP-activated protein kinase) strains were anoxia sensitive at day 1 and displayed increased LTA tolerance with aging correlated with reproductive senescence followed by a decline in survivorhsip through day 9. The daf-2(e1370) (insulin receptor homologue of C. elegans), glp-1(e2141) (a lin-12/Notch receptor) and fog-2(q71) (required for spermatogenesis) strains were LTA-tolerant through day 5. I conclude that aging influences LTA-tolerance in a strain- and age-dependent manner. In addition to being LTA-tolerant the daf-2(e1370) and glp-1(e2141) strains have a longevity phenotype that is suppressed by loss of kri-1 or daf-12. While loss of kri-1 did not suppress the LTA-tolerant phenotype of glp-1(e2141) at day 1 the portion of impaired survivors increased at day 3 …
Date: May 2013
Creator: Goy, Jo M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library