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The Impact of End-user Decision-making in the Supply of Public Transportation
Efficient public transportation provides economic and social opportunities that increase accessibility to markets and employment as well as providing investment benefits. Key challenges to the U.S. public transportation industry include developing modes and increasing the availability of public transportation in a manner that meets the needs of individual users in a cost effective manner. A problem facing public transportation officials is the need to understand the factors that influence consumer decision-making and consumer attitudes toward public transportation. Feedback regarding experiences as well as expectations from commuters provides information for developing and improving public transportation. Thus, decision-making factors of end-users are keys to improving supply, growth, and understanding utilization of public transportation. Public transportation officials seek to improve the public transportation experience for commuters by increasing modes and benefits of the systems. The decision-making factors of the end-users require identification and examination in order to provide a high quality and efficient experience for commuters. The research questions of interest in the current dissertation are: (1) What are the decision-making factors affecting commuters’ attitudes toward public transportation? and (2) How do the end-user decision-making factors affect the supply of public transportation? The purpose of this research is to extend the current body of knowledge about decision-making factors by developing and testing a new theoretical model to measure the attitudes of public transportation end-users. This study has its theoretical foundation in the theory of planned behavior, theory of reasoned action, and rational choice theory. To understand how public transportation is affected by decision-making factors, it is necessary to analyze the relationships among the decision factors and attitudes. The findings of this study contribute by building theory and having implications for practice. This study employs a mixed methodology of qualitative and quantitative research. More specifically, the development of a framework and testing of that framework via collection of data using a survey instrument, semi-structured interviews, and data scraping of customer comments underpin the methodology employed in this study. To this end, Essay 1 develops a conceptual framework of decision-making factors that affect the supply of public transportation based on the extant literature. The integrated framework developed is operationalized using a survey to test a model that depicts the framework within the context to which the study was situated. The results of the structural model using PLS provide insights for the development of public transportation. Essay 2 involves two phases in the methodology. First, the study develops a causal loop that depicts the operationalized conceptual framework from Essay 1. Second, discussion panels were conducted to confirm the system dynamic causal loop visualization that was developed to fit the model. Finally, Essay 3 examines the conceptual framework developed and tested in the prior essays by analyzing electronic word of mouth (eWOM) of online comments. The third essay examines eWOM of current public transportation users that is available online. This eWOM data was examined using text mining and the resulting quantitative output was compared to the operationalized theoretical framework from the prior works. The results also illustrate the functionality of text analytics for confirmatory model assessment. digital.library.unt.edu/ark:/67531/metadc801874/
What Did the Client Say? Auditor Memory of a Client Inquiry: a Study of Encoding Style and Note Taking
Client inquiry is a fundamental procedure for gathering audit evidence. Since inquiries are not audio- or video-recorded in practice, auditor memory is vital to the accuracy of evidence gathered in this manner. Due to the potential for error during memory encoding and retrieval, the effect of memory on judgment, and the cognitive complexity of conducting a face-to-face inquiry, examining factors affecting auditor memory of client inquiries is important. In this dissertation, I examine two factors likely to affect auditor memory of a client inquiry. First, encoding style is a low-level cognitive function representing how much stimuli an individual perceives before applying prior knowledge (schemata) to assist with encoding to long-term memory, affecting information noticed and remembered. Differences in auditors’ encoding style may explain variance in memory accuracy of evidence gathered from a client inquiry. Second, audit professionals often make hand-written or typed notes during client inquiries, and subsequently review the notes, which may affect memory. To address these issues, I first gather interview evidence from six professional auditors to determine how practicing auditors plan, prepare for, conduct, and document evidence from client inquiries. I then develop and execute a video-based experiment with 33 senior auditor participants, 23 masters-level accounting students, and 47 undergraduate-level accounting students to investigate whether encoding style and note taking affect auditor memory accuracy of, and audit judgments resulting from, a client inquiry. I find multiple significant results. First, I find that encoding style affects memory accuracy such that auditors quickly utilizing prior knowledge during an inquiry results in greater memory accuracy than auditors slowly utilizing prior knowledge. This finding suggests that quickly utilizing prior knowledge helps auditors to manage the cognitive complexity of a client inquiry. Second, I find that participants who take notes during an inquiry, and subsequently review his or her notes taken, have lesser memory accuracy than participants who do not take notes. This finding suggests note taking distracts participants during an inquiry, hindering memory accuracy. Third, I find that memory accuracy affects audit judgments such that memory accuracy is positively related to judging the client’s explanation as reasonable, and negatively related to judging the probability of material misstatement and likelihood to increase substantive testing. Finally, I find that encoding style has a significant indirect effect on audit judgment through memory accuracy. This study makes several contributions to audit practice and academic literature. First, this study contributes a discussion of how auditors conduct client inquiries based on interviews with very-experienced auditors from multiple accounting firms, representing various firm sizes. No prior research provides qualitative evidence of how auditors conduct inquiries. Second, this study contributes to the audit literature by finding that encoding style and note taking affect auditor memory accuracy of a client inquiry. Although the findings do not support hypotheses suggested by theory, the findings suggest further research in the topic is warranted. Third, this study contributes to the psychology literature by finding that encoding style affects memory in an information-robust, professional context, extending the generalizability of the encoding style construct beyond the abstract tasks with which it has been previously examined. digital.library.unt.edu/ark:/67531/metadc801881/
The Procedural Generation of Interesting Sokoban Levels
As video games continue to become larger, more complex, and more costly to produce, research into methods to make game creation easier and faster becomes more valuable. One such research topic is procedural generation, which allows the computer to assist in the creation of content. This dissertation presents a new algorithm for the generation of Sokoban levels. Sokoban is a grid-based transport puzzle which is computational interesting due to being PSPACE-complete. Beyond just generating levels, the question of whether or not the levels created by this algorithm are interesting to human players is explored. A study was carried out comparing player attention while playing hand made levels versus their attention during procedurally generated levels. An auditory Stroop test was used to measure attention without disrupting play. digital.library.unt.edu/ark:/67531/metadc801887/
The Effect of Curcumin Supplementation on Physical and Biological Indices of Delayed Onset Muscle Soreness and Inflammation Following Muscle Injury
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In this project, the effects of dietary polyphenols on exercise-induced muscle damage and vascular health are examined. Dietary polyphenols exert well-known anti-inflammatory effects; however, how these effects are realized with respect to vascular health and EIMD is relatively unknown. I begin by reviewing the available literature surrounding the impact of three dietary polyphenols (curcumin, catechins, and quercetin) on inflammation associated with EIMD. It is well established that their primary means of anti-inflammation is through alterations of NF-κB and AP-1 transcription activities. Given this, their inclusion into training strategies seems reasonable. Consistent evidence is presented making a case for the anti-inflammatory effects of dietary polyphenols following EIMD. I follow this review up by completing an in-depth study on the consumption of curcumin prior to EIMD. I found curcumin (1000 mg/day) can reduce subjective soreness and decrease inflammation compared to placebo controls. To further understand the effects of dietary polyphenols on health, I investigate the effects of a four-week supplementation period of cocoa (catechins) on vascular. I concluded that atherogenic risk in obese women is reduced after consumption of cocoa. In addition to these experimental projects, I developed two novel methods that can be used to investigate vascular health (EMP concentration) and intracellular protein and mRNA production using flow cytometry. digital.library.unt.edu/ark:/67531/metadc801906/
Ta/v\am: Real-time Audio/video Scrubbing Tools for Analysis of Multimedia and G®¡nd
tA/v\Am (the Audio/Video Analysis Machine) is an interactive analysis engine optimized for audio/visual mediums, such as film, video games, and music. I designed tA/v\Am to allow users to pace the playback speed of videos containing sub-title style analytical text, without affecting the pitch content of the audio. The software affords writers the opportunity to display the relevant sensory data (i.e., analytical text and sound/visual media) more efficiently than the paper format. It also serves as a flexible medium; the writer may, for example, compress extensive text into a short amount of time, causing the reader to pause or slow down the rate of the video and thus suspending him/her in the sensorial moment which the writer describes. G®¡ND for Alto Saxophone, Percussion & Electronics is an exploration of the tipping point between signal and noise. Through tablature notation, MIR tools, granular synthesis, and the deconstruction of the saxophone, I have assembled a palette of inordinately contrasting sounds and threaded them together based on action profiles obtained by computer assisted analysis. With them, I have set varying physical conditions of friction that dictates whether the sonic energy is to become focused to one resonant point, or distributed equally/randomly throughout the spectrum as noise. In my critical essay, I use the software to analyze independent video games, showing how tA/v\Am is a highly appropriate tool for such analysis as it is an analogous medium. I then show the software's capabilities as a multimedia platform in analyzing acoustic music, as well as my own electroacoustic work, G®¡ND. In doing so, I advocate for a media-driven analyses, and maintain that one can communicate nuanced ideas using minimal verbal/textual explanation. digital.library.unt.edu/ark:/67531/metadc801904/
Vanishing Act
This dissertation is comprised of a collection of poems preceded by a critical preface. The preface reconsiders the value of discontinuous poetic forms and advocates a return to lyric as an antidote to the toxic aspects of what Tony Hoagland terms “the skittery poem of our moment.” I consider poems by Wendy Xu, Kevin Prufer, Sharon Olds, and Stephen Dunn in depth to facilitate a discussion about the value of a more centrist position between the poles of supreme discontinuity and totalizing continuity. Though poets working in discontinuous forms are rightly skeptical of the hierarchies that govern narrative and linear forms, as Czesław Miłosz notes in The Witness of Poetry, “a poet discovers a secret, namely that he can be faithful to real things only by arranging them hierarchically.” In my own poems, I make use of the hierarchies of ordered perception in lyric and narrative forms to faithfully illuminate the collapsed structures of my own family history in the shadow of Detroit. I practice the principles I advocate in the preface, using a continuous form to address fractured realities in a busy, disordered age when poets often seek forms as fragmented as their perceptions. These poems are distinctly American, but because there is no true royalty in America, our great cultural and economic institutions—television, music, film, magazines, and big business—take the place of the castle (the book’s emblem) while Michael Jackson ultimately rises as the commanding dead king whose passing prompts contemplation of the viability of popular culture, family, history, and geography. The fallen structures that litter the work are many: the twin towers, chess rooks, bounce castles, nuclear families, the auto industry. However, the sole structure cohering the whole is that of a lyric voice whose authority is derived through lived experience and presented in rich, continuous poetic forms. digital.library.unt.edu/ark:/67531/metadc801936/
An Application of Marxian and Weberian Theories of Capitalism: the Emergence of Big Businesses in the United States, 1861 to 1890
This study was an examination of businesses that became big businesses in the United States during the time period between the years of 1861 and 1890, a period of time frequently referred to as the “big business era.” The purpose of the study was to identify actions taken by businesses that enabled them to become and remain big businesses. A secondary purpose of the study was to show that these actions were explained by theories of Karl Marx and Max Weber. The results of the study showed that businesses which took specific actions were able to become and remain big businesses and these actions were explained by the theories of Marx and Weber. The results of the study demonstrate the ability of classical sociological theory to explain macro-level social change. digital.library.unt.edu/ark:/67531/metadc801922/
Investigation on Segmentation, Recognition and 3D Reconstruction of Objects Based on Lidar Data Or Mri
Segmentation, recognition and 3D reconstruction of objects have been cutting-edge research topics, which have many applications ranging from environmental and medical to geographical applications as well as intelligent transportation. In this dissertation, I focus on the study of segmentation, recognition and 3D reconstruction of objects using LiDAR data/MRI. Three main works are that (I). Feature extraction algorithm based on sparse LiDAR data. A novel method has been proposed for feature extraction from sparse LiDAR data. The algorithm and the related principles have been described. Also, I have tested and discussed the choices and roles of parameters. By using correlation of neighboring points directly, statistic distribution of normal vectors at each point has been effectively used to determine the category of the selected point. (II). Segmentation and 3D reconstruction of objects based on LiDAR/MRI. The proposed method includes that the 3D LiDAR data are layered, that different categories are segmented, and that 3D canopy surfaces of individual tree crowns and clusters of trees are reconstructed from LiDAR point data based on a region active contour model. The proposed method allows for delineations of 3D forest canopy naturally from the contours of raw LiDAR point clouds. The proposed model is suitable not only for a series of ideal cone shapes, but also for other kinds of 3D shapes as well as other kinds dataset such as MRI. (III). Novel algorithms for recognition of objects based on LiDAR/MRI. Aimed to the sparse LiDAR data, the feature extraction algorithm has been proposed and applied to classify the building and trees. More importantly, the novel algorithms based on level set methods have been provided and employed to recognize not only the buildings and trees, the different trees (e.g. Oak trees and Douglas firs), but also the subthalamus nuclei (STNs). By using the novel algorithms based on level set method, a 3D model of the subthalamus nuclei (STNs) in the brain has been successfully reconstructed based on the statistical data of previous investigations of an anatomy atlas as reference. The 3D rendering of the subthalamic nuclei and the skull directly from MR imaging is also utilized to determine the 3D coordinates of the STNs in the brain. In summary, the novel methods and algorithms of segmentation, recognition and 3D reconstruction of objects have been proposed. The related experiments have been done to test and confirm the validation of the proposed methods. The experimental results also demonstrate the accuracy, efficiency and effectiveness of the proposed methods. A framework for segmentation, recognition and 3D reconstruction of objects has been established, which has been applied to many research areas. digital.library.unt.edu/ark:/67531/metadc801920/
Space and Spectrum Engineered High Frequency Components and Circuits
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With the increasing demand on wireless and portable devices, the radio frequency front end blocks are required to feature properties such as wideband, high frequency, multiple operating frequencies, low cost and compact size. However, the current radio frequency system blocks are designed by combining several individual frequency band blocks into one functional block, which increase the cost and size of devices. To address these issues, it is important to develop novel approaches to further advance the current design methodologies in both space and spectrum domains. In recent years, the concept of artificial materials has been proposed and studied intensively in RF/Microwave, Terahertz, and optical frequency range. It is a combination of conventional materials such as air, wood, metal and plastic. It can achieve the material properties that have not been found in nature. Therefore, the artificial material (i.e. meta-materials) provides design freedoms to control both the spectrum performance and geometrical structures of radio frequency front end blocks and other high frequency systems. In this dissertation, several artificial materials are proposed and designed by different methods, and their applications to different high frequency components and circuits are studied. First, quasi-conformal mapping (QCM) method is applied to design plasmonic wave-adapters and couplers working at the optical frequency range. Second, inverse QCM method is proposed to implement flattened Luneburg lens antennas and parabolic antennas in the microwave range. Third, a dual-band compact directional coupler is realized by applying artificial transmission lines. In addition, a fully symmetrical coupler with artificial lumped element structure is also implemented. Finally, a tunable on-chip inductor, compact CMOS transmission lines, and metamaterial-based interconnects are proposed using artificial metal structures. All the proposed designs are simulated in full-wave 3D electromagnetic solvers, and the measurement results agree well with the simulation results. These artificial material-based novel design methodologies pave the way toward next generation high frequency circuit, component, and system design. digital.library.unt.edu/ark:/67531/metadc801923/
Synthesis of Peropyrene and Tetracene Derivatives for Photochemical Applications
A novel route for the synthesis of the polycyclic aromatic hydrocarbon peropyrene (Pp) is reported along with the efforts to synthesize derivatives of Pp, 2,2′- and 5,5′-linked tetracene dimers as candidates for study as singlet fission materials in photovoltaic devices. Peropyrene was synthesized by the McMurry coupling conditions from phenalenone and low-valent titanium species. The crystal structure of Pp is formed by π-stacked molecular pairs in a herringbone arrangement. The direct functionalization of Pp was studied, and several indirect methods for the functionalization of Pp via phenalenone derivatives are reported. Nucleophilicly dependent, regioselective Michael addition pathways for phenalenone are described. Phenalenone forms a nucleophilic complex with bispinacolatodiboron and yields chiral 3,3′-linked phenalenone dimers and a bicyclo[3.2.1]octane derivative product of an unusual 3,4 addition. An active complex product of phenalenone and (dimethylphenylsilyl)boronic acid pinacolic ester forms Pp directly. The synthesis of 2,2′- and 5,5′-linked tetracene dimers led to the study of the reduction of 1-arylprop-2-yn-1-ol derivatives via TFA-catalyzed hydride transfer from triethylsilane. Substrates with terminal and TMS-protected alkynes showed silane exchange upon reduction. A TMS-protected, terminal alkyne became triethylsilyl-protected by about 50% whereas only triethylsilyl-protected, terminal alkyne was observed from the reduction of an unprotected, terminal alkyne. A new conformational polymorph of 1,4-bis(triisopropylsilyl)buta-1,3-diyne is reported. Five other rotamers are studied by density functional theory as possible candidates of conformational polymorphism by the analysis of torsional strain energies. The relative stabilities and interconversion equilibria of the seven conformational isomers are studied. digital.library.unt.edu/ark:/67531/metadc801958/
Design of Multi Band Microwave Devices Using Coupled Line Transmission Lines
Multi band technology helps in getting multiple operating frequencies using a single microwave device. This thesis presents the design of dual and tri band microwave devices using coupled transmission line structures. Chapter 2 presents the design of a novel dual band transmission line structure using coupled lines. In chapter 3, Design of a dual band branch line coupler and a dual band Wilkinson power divider are proposed using the novel dual band transmission line structure presented in the previous chapter. In chapter 4, Design of a tri band transmission line structure by extending the dual band structure is presented. The Conclusion and future work are presented in chapter 5. digital.library.unt.edu/ark:/67531/metadc801903/
A Multimodal Investigation of Renewal of Human Avoidance, Perceived Threat, and Emotion
Many people who receive exposure-based treatments for anxiety disorders exhibit a return of fear and avoidance which is often referred to as renewal or relapse. Human and nonhuman research on fear conditioning and renewal has been instrumental in helping understand relapse in anxiety disorders. The purpose of this investigation was to examine renewal of human avoidance and assess whether avoidance may aid in sustaining renewal of fear responses. We adopted a multimodal measurement approach consisting of an approach-avoidance task along with ratings of perceived threat and fear and measures of skin-conductance, a widely used physiological measure of fear. A traditional, single-subject research design was used with six healthy adults. All tasks employed a discrete trial procedure. Experimental conditions included Pavlovian fear conditioning in which increased probability of money loss was paired with a “threat” meter in Context A and later followed extinction in Context B. Fear and avoidance increased to higher threat levels in Context A but not Context B. Renewal testing involved presenting the threat meter on a return to Context A to determine if it evoked fear and avoidance (i.e., relapse). As predicted, renewal testing in Context A showed that increased threat was associated with increased avoidance, ratings of perceived threat and fear, and higher skin-conductance. Moreover, results showed that renewal maintained over six blocks of trials. This is the first investigation of renewal of threat and avoidance in humans that highlights avoidance as a mechanism that may contribute to maintaining fear in anxiety pathology. digital.library.unt.edu/ark:/67531/metadc801907/
Act Like a Punk, Sing Like a Feminist: a Longitudinal Content Analysis of Feminist Themes in Punk Rock Song Lyrics, 1970-2009
Punk rock music has long been labeled sexist as copious media-generated accounts and reports of the genre concentrate on male artists, hyper-masculine performances, and lyrics considered to be aggressive, sexist, and misogynist. However, scholars have rarely examined punk rock music longitudinally, focusing heavily on 1980s and 1990s manifestations of the genre. Furthermore, few systematic content analyses of feminist themes in punk rock song lyrics have been conducted. The present research is a longitudinal content analysis of lyrics of 600 punk rock songs released for four decades between 1970 and 2009 to examine the prevalence of and longitudinal shifts in antiestablishment themes, the prevalence of and longitudinal shifts in sexist themes relative to feminist themes, the prevalence of and longitudinal shifts in specific feminist branches, and what factors are related to feminism. Using top-rated albums retrieved from Sputnik Music’s “Best Punk Albums” charts, systematic random sampling was applied to select 50 songs for each combination of three gender types and four decades. Sexism and feminism were then operationalized to construct a coding sheet to examine relevant dimensions. While the present study found no significant patterns of longitudinal increase or decrease in feminist or sexist themes, it revealed that feminist themes were consistently high across four decades and, furthermore, indicated a phenomenon of post-modern hybridity. digital.library.unt.edu/ark:/67531/metadc801944/
Friendship, Politics, and the Good in Aristotle's Nicomachean Ethics
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In Aristotle's Nicomachean Ethics, Books VIII and IX provide A philosophic examination of friendship. While these Books initially appear to be non sequiturs in the inquiry, a closer examination of the questions raised by the preceding Books and consideration of the discussion of friendship's position between two accounts of pleasure in Books VII and X indicate friendship's central role in the Ethics. In friendship, Aristotle finds a uniquely human capacity that helps readers understand the good is distinct from pleasure by leading them to think seriously about what they can hold in common with their friends throughout their lives without changing who they are. What emerges from Aristotle's account of friendship is a nuanced portrait of human nature that recognizes the authoritative place of the intellect in human beings and how its ability to think about an end and hold its thinking in relation to that end depends upon whether it orders or is ordered by pleasures and pains. Aristotle lays the groundwork for this conclusion throughout the Ethics by gradually disclosing pleasures and pains are not caused solely by things we feel through the senses, but by reasoned arguments and ideas as well. Through this insight, we can begin to understand how Aristotle's Ethics is a work of political philosophy; to fully appreciate the significance of his approach, however, we must contrast his work with that of Thomas Hobbes, his harshest Modern critic. Unlike Aristotle, Hobbes is nearly silent on friendship in his political philosophy, and examining his political works especially Leviathan reveals the absence of friendship is part of his deliberate attempt to advance a politics founded on the moral teaching that pleasure is the good. Aristotle's political philosophy, by way of contrast, aims to preserve the good, and through friendship, he not only disentangles the good from pleasure, but shows a level of human community more suitable for preserving the good than political regimes because these communities have more natural bonds than any regime can hope to create between its citizens. digital.library.unt.edu/ark:/67531/metadc801900/
The Best Medicine
The Best Medicine is an animated documentary that explores the true stories behind the live performances of stand-up comedians. The film juxtaposes live stand-up performances with candid interview footage combined with animation and illustration. Three subjects– Michael Burd, Casey Stoddard, and Jacob Kubon– discuss alcoholism, childhood abuse, and sexual anxiety, respectively. Their candid, intimate interviews reveal personal information, creating a new context with which to understand live stand-up comedy performance. This illustrates themes of finding humor in dark or painful circumstances and the cathartic nature writing and performance. digital.library.unt.edu/ark:/67531/metadc801938/
Cross-cultural Differences in the Presentation of Depressive Symptoms
Epidemiological studies show that China has a lower prevalence rate of major depression than that of Western countries. The disparity in prevalence is commonly attributed to the tendency of Chinese to somatize depression. Empirical evidence of Chinese somatization has yielded mixed results. The present study thus aimed to 1) examine differences in somatic and psychological symptom reporting between Chinese from Macau and Americans in America and 2) identify cultural and psychological variables that would predict somatization. Independent and interdependent self-construals, sociotropy, and emotional approach coping were hypothesized to predict somatization of depression. Participants included 353 Chinese and 491 American college students who completed self-report measures online. Contrary to prediction, results indicated that Americans endorsed a higher proportion of somatic symptoms than Chinese did. Sociotropy predicted both relative endorsement and severity of somatic symptoms for the American sample, whereas emotional expression coping was related to somatization in the Chinese sample. The findings challenge the common assumption of greater Chinese somatization and highlight the importance of context in understanding the relationships between somatization and cultural and psychological variables. Implications of the present study and future directions are discussed. digital.library.unt.edu/ark:/67531/metadc801937/
Pathways for C—h Activation and Functionalization by Group 9 Metals
As fossil fuel resources become more and more scarce, attention has been turned to alternative sources of fuels and energy. One promising prospect is the conversion of methane (natural gas) to methanol, which requires an initial activation of a C-H bond and subsequent formation of a C-O bond. The most well studied methodologies for both C-H activation and C-O bond formation involve oxidation of the metal center. Metal complexes with facile access to oxidation states separated by four charge units, required for two subsequent oxidations, are rare. Non-oxidative methods to perform C-H bond activation or C-O bond formation must be pursued in order for methane to methanol to become a viable strategy. In this dissertation studies on redox and non-redox methods for both C-H activation and C-O bond formation are discussed. In the early chapters C-O bond formation in the form of reductive functionalization is modeled. Polypyridine ligated rhodium complexes were studied computationally to determine the properties that would promote reductive functionalization. These principles were then tested by designing an experimental complex that could form C-O bonds. This complex was then shown to also work in acidic media, a critical aspect for product stabilization. In the later chapters, non-oxidative C-H activation is discussed with Ir complexes. Both sigma bond metathesis and concerted metalation deprotonation were investigated. For the former, the mechanism for an experimentally known complex was elucidated and for the latter the controlling factors for a proposed catalyst were explored. digital.library.unt.edu/ark:/67531/metadc801909/
The Microbial Retting Environment of Hibiscus Cannabinus and Its Implications in Broader Applications
Fiber-yielding plants is an area of increased interest due to the potential use in a variety of green-based materials. These biocomposites can be incorporated into multiple uses; for example, to replace building materials and interior vehicular paneling. The research here aims to focus in on the crop Hibiscus cannabinus for utilization into these functions. H. cannabinus is economically attractive due to the entire process being able to be accomplished here in the United States. The plant can be grown in a relatively short growth period (120-180 days), and then processed and incorporated in a biocomposite. The plant fiber must first be broken down into a useable medium. This is accomplished by the retting process, which occurs when microbial constituents breakdown the heteropolysaccharides releasing the fiber. The research aims to bridge the gap between the primitive process of retting and current techniques in molecular and microbiology. Utilizing a classical microbiological approach, which entailed enrichment and isolation of pectinase-producing bacteria for downstream use in augmented microbial retting experiments. The tracking of the bacteria was accomplished by using the 16S rRNA which acts as “barcodes” for bacteria. Next-generation sequencing can then provide data from each environment telling the composition and microbial diversity of each tested variable. The main environments tested are: a natural environment, organisms contributed by the plant material solely, and an augmented version in which pectinase-producing bacteria are added. In addition, a time-course experiment was performed on the augmented environment providing data of the shift to an anaerobic environment. Lastly, a drop-in set was performed using each isolate separately to determine which contributes to the shift in microbial organization. This research provided a much needed modernization of the retting technique. Previous studies have been subject to simple clone libraries and growth plate assays and next-generation sequencing will bring the understanding of microbial retting into the 21st century. digital.library.unt.edu/ark:/67531/metadc801953/
Spanish Measurement of Adult Attachment: Reliability and Validity of the Experiences in Close Relationships Scale in a Hispanic American Sample
Measures of adult attachment developed in English have been translated and validated in multiple Spanish-speaking countries, yet to this date no self-report adult attachment instrument has been systematically examined for validation with Latinos/Hispanic Americans. The present study examined psychometric properties of a Spanish version of a widely used adult attachment scale, the Experiences in Close Relationships Scale (ECRS), with a bilingual college student sample. Following the dual-language split half (DLSH) quantitative method of evaluating semantic equivalence, 209 bilingual, Latinos/Hispanic American college students recruited from a large public university completed a DLSH version of the ECRS (half English, half Spanish). Internal consistency reliability and DLSH reliability were within acceptable limits, although significantly smaller than coefficients of the English ECRS completed by a large Caucasian sample (n = 459); 3- to 8-week test-retest reliability was also adequate. Exploratory factor analysis revealed a two-factor solution with 35 items accounting for 40% of the variance, which was similar to the English ECRS. Convergent validity was supported by findings that showed significant associations of attachment dimensions with social self-efficacy, self-esteem, depressive symptoms, and comfort with self-disclosure, but not interpersonal trust. Evidence for discriminant validity was found in that attachment dimensions were not significantly associated with social desirability. Theoretical implications, limitations, and future directions of the study will be discussed based on adult attachment theory and cross-cultural perspectives. digital.library.unt.edu/ark:/67531/metadc801946/
Professional Learning Community Dimensions in a North Texas Elementary School’s Culture and Their Impact on Reading and Math Student Growth Scores
The purpose of this mixed methods study was to determine which dimensions, as represented by the Professional Learning Community Assessment – Revised dimensions, are present in the environment of North Texas elementary schools and their impact on student growth. A survey design was utilized in which elementary principals and teachers in a selected school district completed the Professional Learning Community – Revised survey developed by Hipp and Huffman (2009), to gather perceptions of PLC implementation within their school environments as well as reflect strengths and needs regarding each dimension. The results of the survey were analyzed and one-to-one interviews were completed to clarify and support survey results. Bivariate and multiple regression analysis were used to determine correlations between dimensions present in a school’s environment and their impact on student growth. The study found a statistically significant relationship between the dimensions of shared values and vision and shared personal practice and math growth. Although PLCA-R dimensions were not found to be statistically significant in predicting reading and math growth, the effect sizes were notable at 22.4% for reading growth and 15.8% for math growth. This study’s findings provide important information which educators can use to implement practical application of Professional Learning Communities within their schools and districts. By understanding which dimensions are present within a school’s environment as well as their impact on student growth, educators can continue to increase knowledge and develop a focused plan for implementing strategies which are effective in strengthening teaching and learning in order to increase student achievement. digital.library.unt.edu/ark:/67531/metadc801961/
A Restorative Environmental Justice for the Prison Industrial Complex: a Transformative Feminist Theory of Justice
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This dissertation provides a feminist restorative model of environmental justice that addresses the injustices found within UNICOR’s e-waste recycling operations. A feminist restorative environmental justice challenges the presupposition that grassroots efforts, law and policy, medical and scientific research, and theoretical pursuits (alone or in conjunction) are sufficient to address the emotional and relational harm of environmental injustices. To eliminate environmental harms, this model uses collaborative dialogue for interested parties to prevent environmental harm. To encourage participation, a feminist restorative model accepts many forms of knowledge and truth as ‘legitimate’ and offers an opportunity for women to share how their personal experiences of love, violence, and caring differ from men and other women and connect to larger social practices. This method of environmental justice offers opportunities for repair, reparation and reintegration that can transform perspectives on criminality, dangerous practices and structures in the PIC, and all persons who share in a restorative encounter. digital.library.unt.edu/ark:/67531/metadc801925/
Understanding Microbial Biodegradation of Environmental Contaminants
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The accumulation of industrial contaminants in the natural environments have rapidly become a serious threat for human and animal life. Fortunately, there are microorganisms capable of degrading or transforming environmental contaminants. The present dissertation work aimed to understand the genomic basis of microbial degradation and resistance. The focus was the genomic study of the following bacteria: a) Pseudomonas fluorescens NCIMB 11764, a unique bacterium with specific enzymes that allow cyanide adaptation features. Potential cyanide degradation mechanisms found in this strain included nit1C cluster, and CNO complex. Potential cyanide tolerance genes found included cyanide insensitive oxidases, nitric oxide producing gene, and iron metabolism genes. b) Cupriavidus sp. strain SK-3 and strain SK-4. The genome of both bacteria presented the bph operon for polychlorinated biphenyl (PCB) degradation, but we found differences in the sequences of the genes. Those differences might indicate their preferences for different PCB substrates. c) Arsenic resistant bacterial communities observed in the Atacama Desert. Specific bacteria were found to thrive depending on the arsenic concentration. Examples were Bacteroidetes and Spirochaetes phyla whose proportions increased in the river with high arsenic concentrations. Also, DNA repair and replication metabolic functions seem to be necessary for resistance to arsenic contaminated environments. Our research give us insights on how bacteria communities, not just individually, can adapt and become resistant to the contaminants. The present dissertation work showed specific genes and mechanisms for degradation and resistance of contaminants that could contribute to develop new bioremediation strategies. digital.library.unt.edu/ark:/67531/metadc801956/
Executive Information Seeking and the Corporate Library
This study began with an interest in corporate libraries and a genuine curiosity in the information preferences and resources valued by executive leaders at JET Aircraft Co. Executive information preferences and the downward trend in special libraries initiated the investigation of information seeking among executive leaders and yielded the inquiry: What resources do JET Aircraft Co. executives value when they need information? Employing an ethnographic approach, this study investigated what JET Aircraft Co. executives know about information resources, what they believe about information resources, and how they act when they require information. While JET Aircraft Co. maintained a special corporate library called the Company Research Library (CRL), the purpose of this study was to determine what resources were of value to executives at JET Aircraft Co., understanding that the CRL may or may not be a resource executives’ value. As a byproduct, this study also sought to establish executive information preferences and perceptions of the CRL. Information seeking at the executive level, studied through an ethnographic lens, provided insight into how executives at JET Aircraft Co. work and what they prefer, and it established a baseline for the Company Research Library’s position among the resources valued by executives. digital.library.unt.edu/ark:/67531/metadc801910/
Investigating Communication and Warning Channels to Enhance Crowd Management Strategies: a Study of Hajj Pilgrims in Saudi Arabia
The global increase in the number of mass gatherings and crowded events has brought with it new emergencies and unintended consequences for public administrators and first responders. Crowd managers attempt to overcome these challenges by enhancing operations, alleviating financial losses, keeping event organizers safe from liability and, most importantly, keeping the attendees safe. Effective communication among and between officials and guests has been identified as a key element in this process. However, there is a lack of risk communication studies, especially about heterogeneous crowds that congregate at religious events. With this gap in mind, this research aims to investigate the use of major communication channels available and/or preferred by Muslim pilgrims in Makkah, Saudi Arabia during Hajj to gauge their effectiveness in communicating risk information. This annual religious pilgrimage was chosen because it attracts over 2 million pilgrims from more than 140 countries, most of whom speak different languages and belong to different cultures but perform the same rituals at the same time. This dissertation seeks to answer three broad research questions: “what are the most popular communication channels used by pilgrims,” “what are the weaknesses of the current communication strategies,” and “what can be done to improve risk communication among pilgrims, and between pilgrims and authorities to enhance crowd control and crowd management strategies.” The protective action decision model (PADM) is used as the theoretical framework to understand the influence of six factors (environmental cues, social cues, information sources, channel access and preferences, warning messages, and receiver characteristics) on risk communication. In collaboration with the Transportation and Crowd Management Center of Research Excellence (TCMCORE) of Saudi Arabia, a convenience sampling strategy was employed to interview 348 pilgrims in the Prophet’s Mosque area, during the Hajj of 2013. The surveys were conducted in Arabic and English and included pilgrims from different backgrounds and countries. Data analysis included an evaluation of the correlation between the use of risk communication channels and receiver characteristics, message content, and information sources. Findings highlight low percentages in the overall use of communication channels. It also demonstrated an over-dependence on channels that foster the passive top-down communication strategy (such as TV stations, messages at mosques, billboard, text messages, and pamphlets), while marginalizing channels that foster the horizontal and bottom-up strategies (such as bilingual staff outreach and social media). The findings also show the differences in risk communication channels used by pilgrims from different socio-demographic groups. The study concludes that adopting bottom-up and horizontal strategies is key to effective risk communication. Additionally, crowd managers must recognize the importance of social media and use this medium more proactively. They can also work towards increasing the overall effectiveness of risk communication channels by addressing the impact of information sources, channel access, and receiver characteristics to better suit the needs of pilgrims. Finally, the study states the limitations and future research directions. digital.library.unt.edu/ark:/67531/metadc801945/
Patient Family and Hospital Staff Information Needs at a Pediatric Hospital: an Analysis of Information Requests Received by the Family Resource Libraries
This research explored the information needs of patient families and hospital staff at a pediatric hospital system in Dallas, Texas. Library statistics recorded in four hospital libraries from 2011 - 2013 were used to analyze the information requests from patient families and hospital staff. Crosstabulations revealed the extent to which patient families and hospital staff used the libraries to satisfy their information needs. The data showed that patient families used the libraries very differently than hospital staff. Chi-square tests for independence were performed to identify the relationships between the Classification (Patient Family, Hospital Staff) and two descriptors of information needs (Request Type, Resources Used). There were a total of 1,406 information requests analyzed. The data showed that patient families and hospital staff information requests differed greatly in the number of information requests, the type of information requested, the resources used and the time the library staff spent on the requests. Chi-square analyses revealed relationships statistically significant at the p < .05 level; however, the strength of the relationships varied. digital.library.unt.edu/ark:/67531/metadc801947/
Academic Reading Online: Digital Reading Strategies of Graduate-level English Language Learners
English language learners (ELLs) face many linguistic and cultural challenges in their attempts to succeed academically. They encounter complex academic text, which is increasingly presented online. Although some research has addressed the challenges that university-level ELLs face when reading online texts, almost all of this prior work has focused on undergraduates. The purpose of the current study was to investigate the reading strategies employed by graduate-level ELLs when reading an academic English text online. Participating in the study were four foreign-born doctoral students from different first-language backgrounds—Arabic, Korean, Urdu, and Vietnamese—and the focus was on commonalities as well as differences among them. All four were enrolled in the same doctoral-level course, which included the reading of a specific online academic article as a course requirement. When reading this text individually, each student participated in a think-aloud procedure, followed by post-reading and discourse-based interviews. Analyses included unitizing data from the think-aloud protocols, coding units for strategies employed, and considering related interview commentary and classroom contributions. In their reading, these students made major use of problem-solving strategies, especially reading segments aloud and questioning. They also employed evaluative strategies as well as metacognitive strategies, which included affirming their understanding or indicating lack of understanding. With respect to global strategies, all made use of the article’s abstract and used the cursor to scroll forward to preview the article. In contrast to previous research with undergraduates, these students made little use of support strategies that involved translation websites. Instead, their major support strategies were navigating to web-based tools, particularly online encyclopedias in English. Despite prior theory and research suggesting the importance of sociorhetorical strategies in academic reading, only one student directed much attention to the authors of the article and to authorial intent. Although all four participants were students in the same doctoral course and were reading the same contextualized article, their strategy use differed in ways that seemed to be related to their educational and cultural backgrounds. Through its detailed analyses of these acts of academic reading, the study contributes to research into the sociocultural nature of ELL students’ reading process. digital.library.unt.edu/ark:/67531/metadc801951/
Determinants of Citizens’ 311 Use Behaviors: 311 Citizen-initiated Contact, Contact Channel Choice, and Frequent Use
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Facing increasingly complex policy issues and diminishing citizen satisfaction with government and service performance, managing the quality of citizen relationship management has become a main challenge for public managers. Solutions to complex policy problems of service performance and low level of citizen participation often must be developed by encouraging citizens to make their voices heard through the various participation mechanisms. Reflecting on this need, the municipal governments in the U.S. have developed centralized customer systems for citizen relationship management. 311 centralized customer system (named 311 in this study) has the functions of citizen-initiated contact, service-coproduction, and transaction, and many local governments launch 311 to maintain or enhance their relationship with the public. Using 311 is an easy and free technically for citizens, but ensuring some degree of citizen engagement and citizens’ 311 use has been challenging for local public managers of municipalities. Despite calls for the importance of 311 in the service and information delivery process, fair treatment and access to use of governmental information, citizen participation, government responsiveness, and citizen satisfaction, to the best of our understanding, no empirical studies explore citizens’ 311 behaviors in the micro and individual level in the field of public administration. This dissertation provides a comprehensive understanding of the 311 centralized customer system, helps local public managers know citizens’ perceived perspectives toward the operation of 311, and assists these managers to develop an effective 311 system in municipalities. The dissertation’s main purpose is to clarify the importance of 311 to citizen relationship management and provide insights into citizens’ 311 use behaviors. More specifically, this dissertation tries to answers the following questions: a. Why do citizens use 311? Do the various groups of the population access and use 311 in San Francisco equally? If not, what factors influence the citizens’ 311 citizen-initiated contact behaviors? b. Why do citizens choose the 311 digital channel to contact with local governments? c. Why do citizens use 311 frequently? This dissertation will address these questions and draws on data from the 2011 citizen survey of City of San Francisco to explore citizens’ 311 use behaviors by examining them from citizens’ perspectives. The main arguments of each question listed above are: 1. 311 citizen-initiated contact is different from traditional citizen-initiated contact, and exposure to governmental-ICT environment, gender, income, and race are the factors influencing 311 citizen-initiated contact. 2. The digital divide, including the social side of the digital divide and access-side of the digital divide, influences citizens’ 311 channel choice. 3. Citizens’ technology acceptance, citizen satisfaction, and frequent use of public services influence the frequency of citizens’ 311 use. digital.library.unt.edu/ark:/67531/metadc801912/
Let the Punishment Fit the Crime: an Overview of the Historical Approach to Probation in the State of Texas
Adult probation evolved in the United States as a result of the suspended sentence concept. As a result of a lack of follow through when an individual obtained a suspended sentence, there was no “checks and balances” to monitor whether an individual completed the guidelines set forth. As time progressed, it became apparent a more cohesive and monitored system was needed. Thus, an energetic and motivated individual, John Augustus, started the concept of probation by taking it upon himself to assist in the rehabilitative process of individuals charged with criminal behavior. Subsequent to his death, the concept of probation was embraced by his advocates who lobbied legislatively in order to enact probation laws that would oversee the success of probationers. It wasn’t until the 1950’s that the counties in the state of Texas took it upon themselves to enact their own system of monitoring of probationers. Over time the states have guided their probation concepts from evidence based research. Juvenile probation in the United States didn’t gain a solid foundation until the end of the 19th century with the development of the first juvenile court in Illinois. It took this country time to understand that juveniles were different than adults mentally; therefore, there would need to be a separation of juveniles from adults from being subjected to the same punishments as adults. The approach in dealing with juveniles was more grounded in treatment rather than in punishment. In the state of Texas, the focus for juvenile probation was based on different approaches based on the areas within the state. The juvenile system has gone through the due process era to its current state of the evidence based research. This thesis will provide the reader an overview of the history of the development of probation in the United States and in the State of Texas, specifically in the two largest counties in Texas. This thesis will go into detail in how probation came into existence to where it is in its current state. digital.library.unt.edu/ark:/67531/metadc801934/
Effect of Friction-stir Processing on the Wear Behavior of Titanium (Ti-1al-8v-5fe) and Stainless Steel (A-286) Alloys
The effect of friction stir processing (FSP) on the mechanical wear behavior was investigated for Ti-1Al-8V-5Fe (Ti-185) and stainless steel (Incoloy® A-286) alloys. The Ti-185 and A-286 alloys were tested in different processing conditions, including as rolled (AR), AR+FSP, and AR+FSP+aged. A high frequency reciprocating rig was used to simulate fretting-type wear of these alloys at room temperature. The Vickers micro-hardness and wear rates were calculated and compared for each processing condition. It was determined that along with increasing hardness in the stir zones, FSP resulted in improved wear resistance for both alloys. Specifically, wear rates in the stir zones were reduced to lowest values of 1.6 x 10-5 and 5.8 x 10-7 mm3/N·m for the AR+FSP+aged Ti-185 and A-286 alloys, respectively, despite lower hardness for A-286 alloy. Mechanistic studies were conducted to determine the reason behind these improvements in wear resistance and the effect of FSP on the microstructural evolution during wear. For the Ti-185 alloy, x-ray diffraction revealed that there was a phase transformation from β-Ti (AR+FSP) to α-Ti (AR+FSP+aged). This phase decomposition resulted in the harder and stiffer Ti phase responsible for lowering of wear rate in Ti-185. While x-ray diffraction confirmed the A-286 alloy retains its austenitic structure for all conditions, scanning electron microscopy revealed completely different wear track morphology structures. There was increased coarse abrasion (galling) with the AR+aged A-286 alloy compared to the much finer-scale abrasion with the AR+FSP+aged alloy, which was responsible for smaller and less abrasive wear debris, and hence lower wear rate. Furthermore, cross-sectional focused ion beam microscopy studies inside the stir zone of AR+FSP+aged A-286 alloy determined that a) increased micro-hardness was due to FSP-induced microscopic grain refinement, and b) the corresponding wear rate decrease was due to even finer wear-induced grain refinement. With both effects combined, the level of damage and surface fatigue wear was suppressed resulting in lowering of the wear rate. In contrast, the absence of FSP-induced grain refinement in the AR+aged A-286 alloy resulted in lower hardness and increasing wear rate. In addition, micro-Raman spectroscopy inside the stir wear zone determined that the wear debris contained metal oxides of Fe3O4, Cr2O3, and NiO, but were a consequence and not the cause of low wear. Overall, FSP of titanium and stainless steel alloys resulted in lowering of wear rates suggesting it is a viable surface engineering technique to target and mitigate site-specific wear. digital.library.unt.edu/ark:/67531/metadc801955/
Disrupting the Discourse of the Other: a Transformative Learning Study of African Art
The primary question of this study is: How does the disruption of African art discourse influence a group of university students’ perceptions of African aesthetics? This inquiry developed from previous studies on the exclusion of modern and contemporary African art in Western art museums. Through the theoretical lens of Postcolonial Theory and Critical Multiculturalism, this research conceptualizes the dominance of traditional African art in art museums, art history, and art education as a Western hegemonic discourse that normalizes perceptions of Africa and African aesthetics as the fixed primitive Other. Thus, this research applied Action Research (AR) methodology coupled with Transformative Learning Theory (TL) to disrupt the discourse of African art; with the purpose of affecting positive changes in perceptions of African aesthetics. The participants for this study were 10 students in a course (Art 1301 Honors Art Appreciation) I instructed at the University of North Texas in the fall (September–December) 2013 semester. Data was collected, analyzed, and interpreted from participants’ assignments and my research journal. This study comprised a dual enquiry on: 1. Discourse and Meaning-making; and 2. Disruption and Transformation. First, the study analyzed students’ perceptions of African aesthetics from their learning experience of traditional African art in an art museum. The findings affirmed traditional African art at the museum as a discourse of Africa as the Other of the West. Secondly, the study analyzed how students’ perceptions were influenced from their experience (in my classroom) of learning histories of modern and contemporary African art that disrupt the authenticity of traditional African art. The findings revealed that 80% of participants developed positive transformations. This research demonstrates how art education grounded in critical theory and transformative learning subverted African art as the discourse of the Other, developed students’ understandings of the multiple realities of Africa and African aesthetics, and encouraged positive transformations in students’ perceptions of African aesthetics. digital.library.unt.edu/ark:/67531/metadc801948/
Classifying Pairwise Object Interactions: A Trajectory Analytics Approach
We have a huge amount of video data from extensively available surveillance cameras and increasingly growing technology to record the motion of a moving object in the form of trajectory data. With proliferation of location-enabled devices and ongoing growth in smartphone penetration as well as advancements in exploiting image processing techniques, tracking moving objects is more flawlessly achievable. In this work, we explore some domain-independent qualitative and quantitative features in raw trajectory (spatio-temporal) data in videos captured by a fixed single wide-angle view camera sensor in outdoor areas. We study the efficacy of those features in classifying four basic high level actions by employing two supervised learning algorithms and show how each of the features affect the learning algorithms’ overall accuracy as a single factor or confounded with others. digital.library.unt.edu/ark:/67531/metadc801901/
Explaining Economic Development Strategies Using Product Differentiation Theory: a Reconceptualization of Competition Among City Governments
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Local governments do not operate in a vacuum. Instead, they are part of a complex “polycentric” system of governments where politically autonomous and self-ruled cities compete with one another over taxable wealth. Missing from the scholarship on metropolitan governance is an understanding of the factors driving competition among local governments. The purpose of this dissertation is to fill this gap by examining how interjurisdictional competition over economic development impacts a city’s choice of strategies for attracting business and residential investment and how those strategies affect revenue collection. First, this dissertation examines whether cities, knowing the economic development strategies of their neighboring cities, pursue similar types of businesses? Or do cities strategically target different types of businesses as a way to avoid the negative consequences of competition? Second, this dissertation explores what impact the decision to pursue similar or dissimilar businesses has on the revenue collection of local governments. Using spatial data analysis to analyze a sample of 2,299 cities, this dissertation finds general support for both theoretical frameworks presented. Overall, the findings from both analyses provide unique insights into metropolitan governance and interjurisdictional competition. digital.library.unt.edu/ark:/67531/metadc801942/
(Some More) American Literature
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This short story collection consists of twenty short fictions and a novella. A preface precedes the collection addressing issues of craft, pedagogy, and the post Program Era literary landscape, with particular attention paid to the need for empathy as an active guiding principle in the writing of fiction. digital.library.unt.edu/ark:/67531/metadc801908/
Application of Cyclic Polarization of Aluminum 3003 Used in All-aluminum Microchannel Heat Exchangers
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All-aluminum microchannel heat exchangers are designed to significantly reduce refrigerant charge requirements, weight, reduced brazed joints, and decreased potential for leakage by increasing reliability. Al 3003 alloy is corrosion resistant and can be formed, welded, and brazed but the issue with all-aluminum heat exchangers is localized corrosion (pitting) in corrosive environments. Currently, there is no universally accepted corrosion test that all coil manufacturers use to characterize their products. Electrochemical testing method of cyclic polarization was employed in this investigation and relevant parameters including electrolyte corrosive agent and its concentration, electrolyte pH, and applied potential scan rate was varied to find an optimal set of parameters. Results of cyclic polarization of Al 3003 in electrolytes containing various concentrations of NaCl were compared with those of the tests in Sea Water Acidified Accelerated Test (SWAAT) electrolyte and it is shown the SWAAT electrolyte (4.2% sea salt acidified to pH of 2.9) is by far stronger (in terms of corrosivity) than typical 3.5% NaCl solution used in most corrosion testing. Corrosion rates (g/m2yr) of Al 3003 measured in this investigation were comparable to those provided by ISO 9223 standard corresponding to C1 through CX categories. Duration of cyclic polarization test is much shorter than that of SWAAT and results obtained in this test is more reproducible compared to those of SWAAT. Scanning electron microscopy micrographs show typical pit depths of about 50 μm. digital.library.unt.edu/ark:/67531/metadc801930/
The Effects of Neighboring, Social Networks, and Collective Efficacy on Crime Victimization: an Alternative to the Systemic Model
The systemic model posits that informal social control directly reduces crime victimization and social networks indirectly reduce crime victimization through informal social control. While empirical testing of the systemic model advanced the theory, important analytical issues remain. First, social networks are inconsistently conceptualized and measured. Second, the conceptual relationship between social networks and informal social control remains unclear. This study addresses these issues by testing an alternative to the systemic model, including new constructs and hypotheses. The goal is to develop better indicators for the model and refine the theory, rethinking and deepening the existing theory about neighborhood effects on crime victimization. The data come from the 2002-2003 Seattle Neighborhoods and Crime Survey (N=2,200). Structural equation modeling (SEM), a multivariate statistical technique, was used to analyze these data. The SEM included five latent constructs (neighboring, neighborhood and non-neighborhood social networks, collective efficacy, and crime victimization) and six social structural variables (racially homogeneous neighborhood, resident tenure, household income, family disruption, male, and non-white ethnicity). One of my 9 hypotheses was supported; the remaining hypotheses were partly supported. The results support my argument that the systemic model is too simplistic, but the relationships among the variables are not exactly as I hypothesized. The results provide insight into the complexities of the systemic model and areas for future research. digital.library.unt.edu/ark:/67531/metadc801962/
Examining Self-efficacy in Community College Adjunct Faculty
Though professional development interventions are widespread in higher education, administrators often do not formally assess their effectiveness, particularly in relation to teacher self-efficacy. The purposes of this study were to determine if any statistically significant difference existed between the self-efficacy scores of adjunct faculty participants in a community college’s professional development program and nonparticipants and to identify the variables with a statistically significant relationship with self-efficacy. A modified version of the Teachers’ Sense of Efficacy Scale (TSES) was administered to 21 adjunct faculty participants in Lone Star College’s Adjunct Certification Program (ACP) and 312 adjunct faculty not currently participating in the program. A demographic questionnaire development by the researcher was also administered. Independent variables of the demographic questionnaire included gender, ethnicity, age, K-12 teaching experience, highest degree earned, subject taught, years of college teaching experience, and number of courses taught each semester. Paired t-test results indicated statistically significant differences in Efficacy in Instructional Strategies for adjunct participants in the ACP program. No significant differences were found for Efficacy in Student Engagement and Efficacy in Classroom Management. Multiple regression analyses indicated that gender has a statistically significant relationship to Efficacy Instructional Strategies. A statistically significant relationship was found for race for Efficacy in Classroom Management. Finally, analysis also indicated a positive relationship between race and gender for Efficacy in Student Engagement. No other statistically significant relationships were found across the other demographic variables. Findings of this study revealed that the ACP increased teacher self-efficacy across two of the three dimensions of the TSES indicating that the professional development intervention had a positive effect on the efficacy of its participants. The present study contributes to the research on teacher self-efficacy, adjunct faculty and professional development interventions. digital.library.unt.edu/ark:/67531/metadc801926/
Transition Metal Catalyzed Oxidative Cleavage of C-o Bond
The focus of this thesis is on C-O bonds activation by transition metal atoms. Lignin is a potential alternative energy resource, but currently is an underused biomass species because of its highly branched structure. To aid in better understanding this species, the oxidative cleavage of the Cβ-O bond in an archetypal arylglycerol β-aryl ether (β–O–4 Linkage) model compound of lignin with late 3d, 4d, and 5d metals was investigated. Methoxyethane was utilized as a model molecule to study the activation of the C-O bond. Binding enthalpies (ΔHb), enthalpy formations (ΔH) and activation enthalpies (ΔH‡) have been studied at 298K to learn the energetic properties in the C-O bond cleavage in methoxyethane. Density functional theory (DFT) has become a common choice for the transition metal containing systems. It is important to select suitable functionals for the target reactions, especially for systems with degeneracies that lead to static correlation effects. A set of 26 density functionals including eight GGA, six meta-GGA, six hybrid-GGA, and six hybrid-meta-GGA were applied in order to investigate the performance of different types of density functionals for transition metal catalyzed C-O bond cleavage. A CR-CCSD(T)/aug-cc-pVTZ was used to calibrate the performance of different density functionals. digital.library.unt.edu/ark:/67531/metadc801914/
Effects of Auditor-provided Tax Services on Book-tax Differences and Investors’ Mispricing of Book-tax Differences
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In this study, I investigate the effect of auditor-provided tax services (ATS) on firms’ levels of book-tax differences and investors’ mispricing of book-tax differences. The joint provision of audit and tax services has been a controversial issue among regulators and academic researchers. Evidence on whether ATS improve or impair the overall accounting quality is inconclusive as a result of the specific testing circumstances involved in different studies. Book-tax differences capture managers’ earnings management and/or tax avoidance intended to maximize reported financial income and to minimize tax expense. Therefore, my first research question investigates whether ATS improve or impair audit quality by examining the relation between ATS and firms’ levels of book-tax differences. My results show that ATS are negatively related to book-tax differences, suggesting that ATS improve the overall audit quality and reduce aggressive financial and/or tax reporting. My second research question examines whether the improved earnings quality for firms acquiring ATS leads to reduced mispricing of book-tax differences among investors. Recent studies document that despite the rich information about firms’ future earnings contained in book-tax differences, investors process such information inefficiently, leading to systematic pricing errors among firms with large book-tax differences. My empirical evidence indicates that ATS mitigate such mispricing, with pricing errors being lower among firms acquiring ATS compared with firms without ATS. Collectively, these results support the notion that ATS improve audit quality through knowledge spillover. Moreover, the improved earnings quality among firms acquiring ATS in turn helps reduce investors’ mispricing of book-tax differences. digital.library.unt.edu/ark:/67531/metadc801928/
An Instructional Guide to Teaching Kurtág’s Játékok Volume I to Beginning and Intermediate Piano Students
Pedagogical methods in piano instruction are constantly evolving. Traditional approaches for beginning students typically focus on teaching music theory and developing the skills necessary to read music. Some contemporary methods, however, are centered on training students to use their whole body while playing the instrument. These more recent methodologies allow students to bond with the piano in a more personal manner, as if they were playing a game with a big toy. One of the most representative works of this approach is the eight-volume collection Játékok (1973) by György Kurtág (b.1926). Volume 1 of Játékok consists of short pieces featuring a new graphic notation devised by Kurtág himself. It also incorporates the use of unusual piano techniques, such as playing with the palm, fist, and forearm. The method also explores the use of the entire range of the instrument. Though the work is over 40 years old, Játékok is only infrequently used as a teaching tool for piano instructors in Hungary, and is unknown in the United States. This probably stems from the fact that it presents students and teachers with atypical musical elements such as unusual notation, use of an unlimited register, and pieces that feature varying degrees of difficulty within the same volume. This study provides a guideline which will assist instructors in implementing Játékok’s Volume 1 effectively as a pedagogical tool by introducing instructor’s teaching content, rearranging the original order of pieces in ascending level of difficulty, and providing a methodology to creatively teach the three most significant musical skills to be developed through Volume 1. digital.library.unt.edu/ark:/67531/metadc801950/
An Evaluation of Matrix Training Approaches for Teaching Compound Labels to Toddlers
Matrix training techniques arrange instruction for stimulus relations that facilitate emergent responding to novel stimulus arrangements, which is a phenomenon known as recombinative generalization. The current study compared two common matrix training approaches, an overlapping (OV) design and a non-overlapping (NOV) design, with respect to arranging relations targeted for training. Two, typically-developing toddlers were taught compound action-object labels in either an OV or NOV matrix training design. Results suggest that an OV matrix design facilitates recombinative generalization more effectively than a NOV design. digital.library.unt.edu/ark:/67531/metadc801954/
Distributed Frameworks Towards Building an Open Data Architecture
Data is everywhere. The current Technological advancements in Digital, Social media and the ease at which the availability of different application services to interact with variety of systems are causing to generate tremendous volumes of data. Due to such varied services, Data format is now not restricted to only structure type like text but can generate unstructured content like social media data, videos and images etc. The generated Data is of no use unless been stored and analyzed to derive some Value. Traditional Database systems comes with limitations on the type of data format schema, access rates and storage sizes etc. Hadoop is an Apache open source distributed framework that support storing huge datasets of different formatted data reliably on its file system named Hadoop File System (HDFS) and to process the data stored on HDFS using MapReduce programming model. This thesis study is about building a Data Architecture using Hadoop and its related open source distributed frameworks to support a Data flow pipeline on a low commodity hardware. The Data flow components are, sourcing data, storage management on HDFS and data access layer. This study also discuss about a use case to utilize the architecture components. Sqoop, a framework to ingest the structured data from database onto Hadoop and Flume is used to ingest the semi-structured Twitter streaming json data on to HDFS for analysis. The data sourced using Sqoop and Flume have been analyzed using Hive for SQL like analytics and at a higher level of data access layer, Hadoop has been compared with an in memory computing system using Spark. Significant differences in query execution performances have been analyzed when working with Hadoop and Spark frameworks. This integration helps for ingesting huge Volumes of streaming json Variety data to derive better Value based analytics using Hive and Spark. digital.library.unt.edu/ark:/67531/metadc801911/
Mapping Overlapping Constellations: Nature and Technology in “Research in Philosophy and Technology”/“techné” and “Environmental Ethics"
The overlap between the separate fields of philosophy of technology and environmental philosophy can be investigated using the two longest running flagship journals for each field, Environmental Ethics (EE) and Research in Philosophy and Technology, which is now published as Techné: Research in Philosophy and Technology (RPT/Techné). By looking at the theoretical and conceptual ideas on nature and the environment expressed in RPT/Techné, at those on technology and artifacts expressed in EE, and at the individuals who contributed them using the principles of social epistemology as developed by Steve Fuller, a stereoscopic view incorporating the insights from both specializations can be constructed. The ideas developed in the articles can be charted like stars within constellations, loosely connected in groupings that are neither clear nor evident. Five constellations can be discerned from the relevant articles in each journal, and while there is some overlap, there is considerable difference. The stereoscopic view is developed in three ways: first, by reviewing the contributions of authors who have published in both journals; second, by utilizing resources in both specializations to add subtlety and depth to the ideas expressed, starting in this case from Jacques Ellul’s “Nature, Technique and Artificiality”; and third, by using W. D. Ross’s ethical theory, which fuses prima facie duties with virtues, to integrate traditional ethical concerns with those raised by philosophers focused on technology and those concerned with the environment. digital.library.unt.edu/ark:/67531/metadc801893/
Computational Studies of C–h/c–c Manipulation Utilizing Transition Metal Complexes
Density Functional Theory (DFT) is an effective tool for studying diverse metal systems. Presented herein are studies of a variety of metal systems, which can be applied to accomplish transformations that are currently difficult/impossible to achieve. The specific topics studied utilizing DFT include: 1) C–H bond activation via an Earth-abundant transition metal complex, 2) C–H bond deprotonation via an alkali metal superbase, 3) and amination/aziridination reactions utilizing a CuI reagent. Using DFT, the transformation to methanol (CH3OH) from methane (CH4) was examined. The transition metal systems studied for this transformation included a model FeII complex. This first-row transition metal is an economical, Earth-abundant metal. The ligand set for this transformation includes a carbonyl ligand in one set of complexes as well as a phosphite ligand in another. The 3d Fe metal shows the ability to convert alkyls/aryls to their oxidized counterpart in an energetically favorable manner. Also, “superbasic” alkali metal amides were investigated to perform C—H bond cleavage. Toluene was the substrate of interest with Cs chosen to be the metal of interest because of the highly electropositive nature of this alkali metal. These highly electrophilic Cs metal systems allow for very favorable C—H bond scission with a toluene substrate. Finally, the amination and aziridination of C–H and C=C bonds, respectively, by a CuI reagent was studied. The mechanism was investigated using DFT calculations. Presently, these mechanisms involving the use of coinage metals are debated. Our DFT simulations shed some insight into how these transformations occur and ultimately how they can be manipulated. digital.library.unt.edu/ark:/67531/metadc801892/
The Burner Project: Privacy and Social Control in a Networked World
As mobile phones become increasingly ubiquitous in today’s world, academic and public audiences alike are curious about the interaction between mobile technologies and social norms. To investigate this phenomenon, I examined how individuals use technology to actively manage their communication behaviors. Through a three-month research project on usage patterns of Burner, a mobile application, this thesis explores the relationships among technology, culture, and privacy. Burner is a service that equips individuals with the means to create, maintain, and/or dissolve social ties by providing temporary, disposable numbers to customers. The application offers a way to communicate without relying on a user’s personal phone number. In other words, Burner acts as a “privacy layer” for mobile phones. It also provides a valuable platform to examine how customers use the application as a strategy for communication management. This thesis represents a marriage of practice and theory: (1) As an applied enterprise, the project was constructed as a customer needs assessment intending to examine how the service was situated in the lives of its users. The findings have successfully been applied to my client’s company strategy and have led to a more informed customer approach. (2) As an academic endeavor, this research contributes to existing scholarship in anthropology, computer-mediated communication, privacy, and design. The results provide rich fodder for discussions about the impact of mobile communication and services. digital.library.unt.edu/ark:/67531/metadc801891/
Combinatorial Assessment of the Influence of Composition and Exposure Time on the Oxidation Behavior and Concurrent Oxygen-induced Phase Transformations of Binary Ti-x Systems
The relatively low oxidation resistance and subsequent surface embrittlement have often limited the use of titanium alloys in elevated temperature structural applications. Although extensive effort is spent to investigate the high temperature oxidation performance of titanium alloys, the studies are often constrained to complex technical titanium alloys and neither the mechanisms associated with evolution of the oxide scale nor the effect of oxygen ingress on the microstructure of the base metal are well-understood. In addition lack of systematic oxidation studies across a wider domain of the alloy composition has complicated the determination of composition-mechanism-property relationships. Clearly, it would be ideal to assess the influence of composition and exposure time on the oxidation resistance, independent of experimental variabilities regarding time, temperature and atmosphere as the potential source of error. Such studies might also provide a series of metrics (e.g., hardness, scale, etc) that could be interpreted together and related to the alloy composition. In this thesis a novel combinatorial approach was adopted whereby a series of compositionally graded specimens, (Ti-xMo, Ti-xCr, Ti-xAl and Ti-xW) were prepared using Laser Engineered Net Shaping (LENS™) technology and exposed to still-air at 650 °C. A suite of the state-of-the-art characterization techniques were employed to assess several aspects of the oxidation reaction as a function of local average composition including: the operating oxidation mechanisms; the structure and composition of the oxides; the oxide adherence and porosity; the thickness of the oxide layers; the depth of oxygen ingress; and microstructural evolution of the base material just below the surface but within the oxygen-enriched region. The results showed that for the Ti-Mo, Ti-Al and Ti-W systems a parabolic oxidation rate law is obeyed in the studied composition-time domain while Ti-Cr system experiences a rapid breakaway oxidation regime at low solute concentrations. The only titanium oxide phase present in the scale for all the binary systems was identified as rutile (TiO2) and formation of multiphase oxide scales TiO2+Al2O3 in Ti-Al system and TiO2+TiCr2 in Ti-Cr system was observed. A thermodynamic framework has been used to rationalize the oxygen-induced subsurface microstructural transformations including: homogeneous precipitation of nano-scaled β particles and discontinuous precipitation of +β phases in Ti-Mo and Ti-W system, evolution of TiCr2 intermetallic phase in Ti-Cr system and ordering phase transformation in Ti-Al system. digital.library.unt.edu/ark:/67531/metadc801898/
Gis in Ap Human Geography: a Means of Developing Students’ Spatial Thinking?
Geography education is undergoing change in K-12 education due in part to the introduction of geospatial technologies, including geographic information systems (GIS). Although active engagement in GIS mapping would seem to enhance students’ spatial thinking, little is known about the mapping strategies that students employ or about changes in their geographic knowledge that would result. This study, set in a high school Advanced Placement human geography class, sought to contribute to these areas of inquiry. Participants performed a web-based GIS task focused on global population and migration. Attention in the study was on (a) the strategies students employed when investigating geographic phenomena using GIS, (b) changes in their cognitive maps, as assessed through sketch maps, resulting from the activity, (c) the relationship between GIS maps and sketch maps, and (d) the ways in which a subset of students serving as case studies explained the nature of their mapping. The study employed screen-captures, video-recordings, observations, pre- and post-study sketch maps, and interviews. Analyses of the GIS process revealed that, in creating their maps, the students used a number of strategies, which included searching, layering, removing layers of data, adjusting transparency, editing, and noting. Although searching and layering were employed by all students, there was variability across students in use of the other strategies. With respect to changes in their spatial thinking, analyses of the sketch maps showed increases in elaboration and accuracy in terms of migration patterns. When GIS maps were compared to sketch maps, analyses showed relations for many students. The six students who served as case studies revealed major connections between personal interests and the reasoning employed in mapping. They also described their entry points into the process. The study shows how real-time data collection, including screen captures, as well as more static measures, specifically sketch maps, can provide insights into the spatial thinking of students while using GIS. It provides some support to educational approaches to geography in which students become creators of maps, not simply users of maps, and suggests that, through their own mapping process, students expand their cognitive maps and enhance their spatial thinking. digital.library.unt.edu/ark:/67531/metadc801894/
Marvels of the Invisible
This dissertation is comprised of a collection of poems preceded by a critical preface. The preface considers the consumed animal body as a metaphor in contemporary American poetry, specifically in the works of Galway Kinnell, Li Young Lee, and Brigit Pegeen Kelly. The consumption of the mute creature allows the poet to identify the human self in the animal other, and serves as a metaphor for our continuity with the natural world. I revise Owen Barfield’s notion of “original participation,” positing that through imaginative participation, the poet and the reader can identify the animal within the self, and thus approach a fuller understanding of both the self and the outside world. We identify the animal other within the human self, and in of this act of relating, we are able to temporarily transgress the boundaries of the individual self to create art that expresses continuity with the outside world. This argument brings about a discussion of text as an act of consumption, and the way and which this can symbolize the ways in which the self is altered through the act of reading. The book-length collection of poems, entitled Marvels of the Invisible, won Tupelo Press’s 2014 Berkshire prize for a first or second book of poetry. The poems look to sources like 17th and 18th century scientific letters, modern and contemporary art, and recent studies in biological phenomena in order to parse the intersection between personal experience and the outside world. The title of the collection points to the conceptual interests of the book: through the lens of scientific phenomena, memory, and personal history, one begins to see that what seems very small (the ant under a microscope, a Russian nesting doll, two people on horseback) are, in fact, individual offerings that articulate one’s place in the cosmos. The collective voice I advocate in the critical preface appears in these poems, especially “Echolocation,” “My Name in Sleep,” “Civilization,” and “Narrative,” all of which make use of the animal-as-metaphor. This collective voice is particularly female, and deals with motherhood, loss, and childhood experience. Poetry, as part-myth, longs to transgress the felt boundaries of the self; it must see that self as inextricably dependent on the natural world. digital.library.unt.edu/ark:/67531/metadc801890/
The Palestinian Archipelago and the Construction of Palestinian Identity After Sixty-five Years of Diaspora: the Rebirth of the Nation
This dissertation conceptualizes a Palestinian archipelago based on Mikhail Bakhtin’s theory of the chronotope, and uses the archipelago model to illustrate the situation and development of Palestinian consciousness in diaspora. To gain insight into the personal lives of Palestinians in diaspora, This project highlights several islands of Palestinian identities as represented in the novels: Dancing Arabs, A Compass for the Sunflower, and The Inheritance. The identities of the characters in these works are organized according to the archipelago model, which illustrates how the characters rediscover, repress, or change their identities in order to accommodate life in diaspora. Analysis reveals that a major goal of Palestinian existence in diaspora is the maintenance of an authentic Palestinian identity. Therefore, my description of the characters’ identities and locations in the archipelago model are informed by various scholars and theories of nationalism. Moreover, this dissertation illustrates how different Palestinian identities coalesce into a single national consciousness that has been created and sustained by a collective experience of suffering and thirst for sense of belonging and community among Palestinians. Foremost in the memories of all Palestinians is the memory of the land of Palestine and the dream of national restoration; these are the main uniting factors between Palestinians revealed in my analysis. Furthermore, this project presents an argument that developing a Palestinian exceptionalism as both a response and a solution to the problems Palestine faced in the 20th century has already occurred among diasporic Palestinians as well as those settled in the West Bank. In addition, a significant finding of this dissertation is the generation clash in regarding to the methods of modernization of the West Bank society between the settled Palestinian and those returning from diaspora. Nevertheless, a Palestinian homecoming will require a renegotiation of Palestinian identities in which generation gaps and other disagreements will be resolved and transcended in favor of nation-state building. digital.library.unt.edu/ark:/67531/metadc801889/
Belief Transfers in Co-branding and Brand Extension and the Roles of Perceptual Fit
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Existing co-branding and brand extension research generally coalesces around two important constructs: perceptual fit and attitude toward the brand. Studies in co-branding and brand extension to date have generally emphasized the transference of affective elements of attitude from parent brand to the extension. Researchers and practitioners clearly need to learn more about the transfer of belief, the cognitive elements of attitude. Too little is currently known about whether and how beliefs are actually transferred in co-branding and brand extension applications, particularly in terms of perceptual fit. This dissertation investigates belief transfer and the effect of perceptual fit on belief transfer in co-branding and brand extension scenarios and develops answers to the following research questions: 1.Are different categories of beliefs transferable from parent brand to theextension? 2.How do various sub-dimensions of perceptual fit affect belief transfers fromparent brands to the extension? 3.How do different categories of beliefs affect consumers’ intentions to purchasethe extension products? Categorization Theory was used as the fundamental theory to build the hypotheses. This dissertation involved qualitative studies, belief scale development, and experimental design studies. The results revealed that aesthetic and functional beliefs are positively transferred from parent brand to the extension. The transfer of aesthetic beliefs is affected by the level of brand fit while the transfer of functional beliefs is independent upon the level of any perceptual fit construct. Finally, cognitive structure based on the strength of extension beliefs is more predictive upon the purchase intention. Findings will extend the co-branding and brand extension literature, especially in terms of the pattern of belief transfers that unfold subject to the influence of various perceptual fit constructs. The results will also provide additional insights about the role that perceptual fit plays in influencing categories of consumer beliefs as those beliefs are also influenced by the specific perceptual fits that are presumably transferred to the extension. digital.library.unt.edu/ark:/67531/metadc801896/
Restoration Techniques for Northern Bobwhites
Isolated populations of northern bobwhites (Colinus virginianus) have declined causing many quail managers to attempt population restoration by releasing captive-reared bobwhites or translocating wild bobwhites. I evaluated three restoration techniques: (1) release of captive-reared bobwhites, (2) translocation of bobwhites from high densities to low densities, and (3) release of captive-reared and translocated bobwhites acclimated on site prior to release. These results show that captive-reared birds have reduced survival and fewer nesting attempts when compared to translocated birds and that acclimation time was not a factor. I hypothesized that high mortality rates were caused by captive-reared birds exhibiting different predator avoidance behavior than wild birds. Captive-reared and wild-trapped bobwhites were subjected to independent predator simulations and their responses were recorded on high definition video. Threat recognition time, reaction type, and reaction time was recorded for comparative analysis. Pen-reared birds recognized the simulated raptorial and terrestrial predator threats quicker than wild-trapped birds, but reaction times were not different among groups. However, the type of reaction was different among groups where pen-reared birds typically flushed immediately upon recognizing either simulated predator as compared to wild-trapped birds which typically ran or held when subjected to the raptorial threat and showed little to no observable reaction to the terrestrial threat. These results reveal a potential loss of a holding trait in pen-reared birds, resulting in a quicker revealing of their position in the presence of a threat, thereby increasing their risk of predation. digital.library.unt.edu/ark:/67531/metadc801897/
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