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Building Specialized Collections from Web Archiving (open access)

Building Specialized Collections from Web Archiving

Short paper presented at Artificial Intelligence for Data Discovery and Reuse (AIDR). This short paper presents work on creating datasets of high-value publications and documents from web archives that can be used for machine learning research to help classify these large collections of data.
Date: May 2019
Creator: Caragea, Cornelia & Phillips, Mark Edward
Object Type: Paper
System: The UNT Digital Library
The Civilian Conservation Corps in Big Bend National Park (open access)

The Civilian Conservation Corps in Big Bend National Park

During the New Deal, the Civilian Conservation Corps (CCC) put young men to work in state and national parks across the United States. One of such parks, Big Bend National Park, is the focus of this study. The CCC had two camps within the park, one from 1934 to 1937 and another from 1940 to 1942. During their time in Big Bend, the CCC constructed many projects including a road, trails, cabins, and other various structures. The purpose of this study is to delineate the role of the CCC in creating Big Bend National Park and the experience of the CCC during their time in the Big Bend camp. This study determines the role of the CCC through a discussion of the planning done by the CCC for Big Bend National Park and the work completed by the CCC in the park. In doing so, it argues that the CCC played a substantial and significant role in the development and character of the park. This study works to understand the experience of the CCC in Big Bend through a discussion of education, safety, and an investigation of a commanding officer. Through this discussion, the role of the federal government and …
Date: May 2019
Creator: Jackson, Kimberly
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Cold-Formed Steel Member Connections Using BAC Screw Fasteners

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In this project, the main research objective is intend to seek criteria for evaluating the capacity of BAC screw fasteners with mixed configuration of waterproof seal washer, sealer tape and different pre-drill holes to determine shear and tension strength values for the screws used in cold-formed steel connections. The thesis presents the design methods and test program conducted to investigate the behavior and strength of the screw connections in shear and tension test. Test results were compared with AISI design provisions to determine if new design equations will be developed for those screws used in BAC cooling tower applications. LRFD resistance factors and ASD safety factors were investigated to the proposed design equations.
Date: May 2019
Creator: Li, Xun
Object Type: Thesis or Dissertation
System: The UNT Digital Library
College and Career Readiness of Students with Autism (open access)

College and Career Readiness of Students with Autism

With one in every 59 individuals now diagnosed with autism spectrum disorder (ASD), there is a significant increase in college enrollment for these students, yet, alarmingly, this population has the highest college dropout rate. Using Rawl's social justice theory as the frame, this qualitative study identified the perceptions of students with ASD, their college professors, and the director of the Office of Disability Accommodation (ODA). Perceptions were examined through open-ended surveys regarding awareness of autism, knowledge of student civil rights, and the availability and adequacy of resources provided through the ODA. In addition, the students with autism participated in semi-structured face-to-face interviews. The findings of this study are consistent with other studies in reflecting barriers experienced by students with ASD, such as poor transition planning, communication, and self-advocacy limitations. The variance among reported perceptions revealed a lack of awareness and continuity of resources and support for students with autism, hindering their successful transition from high school to and through post-secondary education. Both students and professors expressed a lack of knowledge of students' rights at the college level and of how to access needed accommodations. These findings reveal the need for a greater awareness of supports needed by students with ASD …
Date: May 2019
Creator: Stello, Christina N
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Comparison and Genetic Analysis of Host Specificity in Cluster BD1 Bacteriophages infecting Streptomyces (open access)

Comparison and Genetic Analysis of Host Specificity in Cluster BD1 Bacteriophages infecting Streptomyces

Bacteriophages are viruses that specifically infect bacteria. When a phage infects a bacterium, it attaches itself to the surface of the bacteria and injects its DNA into the intracellular space. The phage DNA hijacks the cellular machinery of the bacteria and forces it to produce phage proteins. Eventually, the bacteria cell bursts or lyses, releasing new phage. The bacteria act as a host for phage reproduction. The ability for a phage to infect multiple bacterial species is known as host range. In siphoviridae bacteriophages, host range is thought to primarily be determined by proteins at the tip of their tail fibers. These proteins act as anti-receptors to specific receptors on the surface of bacteria. In siphoviridae Gram-positive infecting phages, the genes that code these proteins are typically located between the tape measure protein gene and the endolysin gene. It is hypothesized that phages that have similar anti-receptor proteins will have similar host range. In this study, the host ranges of 12 BD1 bacteriophages were tested on 9 different Streptomyces species. In these 12 phages, the genes between the tape measure protein gene and endolysin gene were compared. The 12 phages had high levels of variability in these genes. Five genes …
Date: May 2019
Creator: Klug, Hannah
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Complex-Restricted Repetitive Patterns of Vocal Behavior of Individuals with High Functioning Autism: An Innovative Intervention

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Repetitive verbal patterns of speech are a trait associated with high-functioning autism (HFA). For some, this higher-order restricted, repetitive behavior impedes learning, social opportunities, and access to work environments. Despite emerging motivation for establishing social relationships, some individuals with HFA lack the behavioral prerequisites to establish meaningful relationships. The purpose of this study is to demonstrate the effectiveness of teaching interaction to decrease higher-order verbal restricted and repetitive behaviors (RRBs) for four adults with HFA. Through a multiple baseline design across participants, individuals were exposed to a function-based intervention (i.e., teaching interaction) that systematically taught and reinforced alternative communicative behaviors while interrupting repetitive speech with specific feedback. Teaching interaction effectively reduced RRBs and increased alternative conversation for all four participants. Three of the four participants elected to participate in post-intervention maintenance sessions that occurred in individualized naturalistic settings. Their conversation behaviors maintained with one participant receiving one booster session.
Date: May 2019
Creator: Flatt, Kimberlee Kay
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Computational and Experimental Studies of the Photoluminescence, Reactivity and Structural Properties of d10 and d8 Metal Complexes (open access)

Computational and Experimental Studies of the Photoluminescence, Reactivity and Structural Properties of d10 and d8 Metal Complexes

Computational chemistry has gained interest as a characterization tool to predict photoluminescence, reactivity and structural properties of organic and transition metal complexes. With the rise of methods including relativity, these studies have been expanded to the accurate modeling of luminescence spectra of complexes with considerable spin-orbit splitting due to heavy metal centers as well as the reaction pathways for these complexes to produce natural products such as hydrogen gas. These advances have led to the synthesis and utility of more effective catalysis as well as the development of more effective organic light emitting diodes (OLEDs) through the incorporation of organometallic complexes as emitters instead of typical organic emitters. In terms of significant scientific advancement presented in this work is in relation to the discovery of significant spin-orbit splitting in a gold(I) alkylphosphine complex, where the splitting results in the states that emit in different colors of the visible region of the electromagnetic spectrum. This work also reveals the discovery both computationally and experimentally, of a genuine polar-covalent bond between two-closed shell metals. This work highlights a complex with an incredibly short gold(I) – copper(I) intermetallic distance leading to a vibrational frequency and dissociation energy that is on par with those …
Date: May 2019
Creator: Otten, Brooke Michelle
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Computational Studies of C-H Bond Activation and Ethylene Polymerization Using Transition Metal Complexes

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This work discusses the C-H bond activation by transition metal complexes using various computational methods. First, we performed a DFT study of oxidative addition of methane to Ta(OC2H4)3A (where A may act as an ancillary ligand) to understand how A may affect the propensity of the complex to undergo oxidative addition. Among the A groups studied, they can be a Lewis acid (B or Al), a saturated, electron-precise moiety (CH or SiH), a σ-donor (N), or a σ-donor/π-acid (P). By varying A, we seek to understand how changing the electronic properties of A can affect the kinetics and thermodynamics of methane C–H activation by these complexes. For all A, the TS with H trans to A is favored kinetically over TS with CH3 trans to A. Upon moving from electron-deficient to electron-rich moieties (P and N), the computed C–H activation barrier for the kinetic product decreases significantly. Thus, changing A greatly influences the barrier for methane C–H oxidative addition by these complexes. Secondly, a computational study of oxidative addition (OA) of methane to M(OC2H4)3A (M = Ta, Re and A = ancillary ligand) was carried out using various computational methods. The purpose of this study was to understand how variation …
Date: May 2019
Creator: Parveen, Riffat
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Computational Studies of Catalysis Mediated by Transition Metal Complexes

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Computational methods were employed to investigate catalytic processes. First, DFT calculations predicted the important geometry metrics of a copper–nitrene complex. MCSCF calculations supported the open-shell singlet state as the ground state of a monomeric copper nitrene, which was consistent with the diamagnetic character deduced from experimental observations. The calculations predicted an elusive terminal copper nitrene intermediate. Second, DFT methods were carried out to investigate the mechanism of C–F bond activation by a low-coordinate cobalt(I) complex. The computational models suggested that oxidative addition, which is very rare for 3d metals, was preferred. A π–adduct of PhF was predicted to be a plausible intermediate via calculations. Third, DFT calculations were performed to study ancillary ligand effects on C(sp3)–N bond forming reductive elimination from alkylpalladium(II) amido complexes with different phosphine supporting ligands. The dimerization study of alkylpalladium(II) amido complexes indicated an unique arrangement of dative and covalent Pd-N bonds within the core four-membered ring of bimetallic complexes. In conclusion, computational methods enrich the arsenal of methods available to study catalytic processes in conjunction with experiments.
Date: May 2019
Creator: Jiang, Quan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
A Data-Driven Computational Framework to Assess the Risk of Epidemics at Global Mass Gatherings (open access)

A Data-Driven Computational Framework to Assess the Risk of Epidemics at Global Mass Gatherings

This dissertation presents a data-driven computational epidemic framework to simulate disease epidemics at global mass gatherings. The annual Muslim pilgrimage to Makkah, Saudi Arabia is used to demonstrate the simulation and analysis of various disease transmission scenarios throughout the different stages of the event from the arrival to the departure of international participants. The proposed agent-based epidemic model efficiently captures the demographic, spatial, and temporal heterogeneity at each stage of the global event of Hajj. Experimental results indicate the substantial impact of the demographic and mobility patterns of the heterogeneous population of pilgrims on the progression of the disease spread in the different stages of Hajj. In addition, these simulations suggest that the differences in the spatial and temporal settings in each stage can significantly affect the dynamic of the disease. Finally, the epidemic simulations conducted at the different stages in this dissertation illustrate the impact of the differences between the duration of each stage in the event and the length of the infectious and latent periods. This research contributes to a better understanding of epidemic modeling in the context of global mass gatherings to predict the risk of disease pandemics caused by associated international travel. The computational modeling and …
Date: May 2019
Creator: Alshammari, Sultanah
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Decision Making in Alternative Modes of Transportation: Two Essays on Ridesharing and Self-Driving Vehicles

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This manuscript includes an investigation of decision making in alternative modes of transportation in order to understand consumers' decision in different contexts. In essay 1 of this study, the motives for participation in situated ridesharing is investigated. The study proposes a theoretical model that includes economic benefits, time benefits, transportation anxiety, trust, and reciprocity either as direct antecedents of ridesharing participation intention, or mediated through attitude towards ridesharing. Essay 2 of this study, focuses on self-driving vehicles as one of the recent innovations in transportation industry. Using a survey approach, the study develops a conceptual model of consumers' anticipated motives. Both essays use partial least square- structural equation modeling for assessing the proposed theoretical models.
Date: May 2019
Creator: Amirkiaee, Seyede Yasaman
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Defining Components Linked to Bacterial Nutritional Utilization of Cyanide as a Sole Nitrogen Source

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One of the challenges in biology is placing a function on the myriad of gene sequences having become available from rapid advances in genome sequencing. One such example is a gene cluster (Nit1C) found in bacteria that is tied to the unusual ability of certain bacteria to grow when supplied cyanide as the sole nitrogen source. The term cyanotrophs has been applied to such bacteria, for which a genetic linkage between cyanotrophy and Nit1C was demonstrated for 10 separate bacteria. In addition to growth, cyanide induced the expression of Nit1C genes in all organisms tested, and in one case, deletion of one of the Nit1C genes (nitC) caused a loss of growth. Of the ten bacteria able to grow cyanotrophically, all gave evidence of harboring Nit1C on their genome except for two (Pseudomonas fluorescens Pf11764 and P. monteilii BCN3), which were sequenced and the presence of Nit1C was also confirmed. A broader search of bacteria identified 270 separate strains with the cluster, all limited to bacteria spanning the phyla Firmicutes, Actinobacteria, Proteobacteria and Cyanobacteria. Remarkably, many examples of a single representative of a given taxon contained Nit1C, most poignantly displayed by Pf11764 and PmBCN3; the interpretation being the cluster was …
Date: May 2019
Creator: Jones, Lauren Brittany
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Denim Fiberboard Fabricated from MUF and pMDI Hybrid Resin System (open access)

Denim Fiberboard Fabricated from MUF and pMDI Hybrid Resin System

In this study, a series of denim fiberboards are fabricated using two different resins, malamine urea formaldehyde (MUF) and polymeric methylene diphenyl diisocyanate (pMDI). Two experimental design factors (1) adhesive content and (2) MUF-pMDI weight ratio, were studied. All the denim fiberboard samples were fabricated following the same resin blending, cold-press and hot-press procedures. The physical and mechanical tests were conducted on the fiberboard following the procedures described in ASTM D1037 to obtain such as modulus of elasticity (MOE), modulus of rupture (MOR), internal bond (IB), thickness swell (TS), and water absorption (WA). The results indicated that the MOE was significantly affected by both factors. IB was affected significantly by weight ratio of different glue types, with 17 wt% more MDI resin portion in the core layer of the denim boards, the IB for total adhesive content 15% fiberboard was enhanced by 306%, while for total adhesive content 25% fiberboard, enhanced by 205%. TS and WA, with higher adhesive content used in denim boards' fabrication, and more pMDI portion in the core layer of the boards, the boards' TS and WA was reduced by up to 64.2% and 78.8%, respectively.
Date: May 2019
Creator: Cui, Zhiying
Object Type: Thesis or Dissertation
System: The UNT Digital Library
A Descriptive Study of the Musical Backgrounds of Orchestral Concert Attendees, with an Emphasis on Past Participation in School Music Programs (open access)

A Descriptive Study of the Musical Backgrounds of Orchestral Concert Attendees, with an Emphasis on Past Participation in School Music Programs

This was a descriptive study that was completed to gather information about musical backgrounds of orchestral concert attendees, and to determine if those attendees perceived relationships between past participation in school music programs and current patronage of classical music concerts. Participants completed a survey about their musical experiences from childhood through adulthood, as well as memories from school music programs. Results and analysis of the responses identified common themes among participants' childhoods, their schooling and private lessons, experiences that served as gateways to classical music listening, the aesthetic benefits that they found in concert attendance, and negative responses that they had to music participation. Results also found a large number of pieces and composers that participants recalled from past participation in school music programs. Findings from this study analyze why these experiences were important to participants and why they might serve as motivation to attend classical music concerts or continue to support them. Implications of this study include suggestions for professional music organizations, school music educators, professional classical musicians, and church music directors. Suggestions for further research based on this study's findings are also included.
Date: May 2019
Creator: Pearce, Kevin (Conductor)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Design of Voltage Boosting Rectifiers for Wireless Power Transfer Systems (open access)

Design of Voltage Boosting Rectifiers for Wireless Power Transfer Systems

This thesis presents a multi-stage rectifier for wireless power transfer in biomedical implant systems. The rectifier is built using Schottky diodes. The design has been simulated in 0.5µm and 130nm CMOS processes. The challenges for a rectifier in a wireless power transfer systems are observed to be the efficiency, output voltage yield, operating frequency range and the minimum input voltage the rectifier can convert. The rectifier outperformed the contemporary works in the mentioned criteria.
Date: May 2019
Creator: Suri, Ramaa Saket
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Design, Synthesis and Characterization of Polymer and Protein Coated Hybrid Nanomaterials: Investigation of Prototypes for Antimicrobial and Anticancer Applications

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This work involves synthesis and characterization of isotropic and anisotropic noble metal nanoparticles for applications ranging from antimicrobial uses to anticancer applications. These nanomaterials are stabilized in genuinely benign biomaterials ranging from polymers to cross linked proteins for targeted cancer treatments. The nanoparticles are found to have tunable optical properties.
Date: May 2019
Creator: Korir, Daniel Kiplangat
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Developing a Multicontextual Model of High Schools whose Students Participate in Financial Aid Preparation Services: Family, School, and Community Level Effects (open access)

Developing a Multicontextual Model of High Schools whose Students Participate in Financial Aid Preparation Services: Family, School, and Community Level Effects

The purpose of this quantitative secondary data analysis was to examine the effect of family, school, and community context on high schools whose students participate in financial aid preparation services. Data from the High School Longitudinal Study of 2009 were analyzed to answer the two research questions using Perna's conceptual model of college enrollment behaviors that explores how students gain and utilize information about financial aid and college prices. Descriptive statistics were used to determine the extent of high school participation in financial aid services. The results indicated a varying degree of these interventions being offered at high schools ranging from 22% to 52%. Schools sending students reminders of FAFSA deadlines (52%) and disseminating flyers/pamphlets on financial aid (50%) were the only two interventions that had a slight majority of schools participating. Multiple regression was used to determine if a relationship existed between the outcome variable (participation in financial aid preparation services) and several family context and school context predictor variables for eight financial aid interventions. Results revealed school context variables as the best predictors of the outcome variable. Counselor caseload and school control were the most effective in predicting high school participation in the eight financial aid preparation services, …
Date: May 2019
Creator: Perez, Consuela
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Development and Testing of Gold(I) and Europium(III) Based Sensors for Environmental Applications

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This dissertation focuses on the development, characterization, and analysis of luminescent materials and coatings for sensing applications, including CO2, heavy metals, and silver. Chapter 2 involves the use of a gold(I) pyrazolate trimer that is able to detect silver ions with an AgNP medium. Detection of silver is vital, because there is an influx of silver into our environment caused by the increased use of AgNP. Therefore, having a sensor that is able to differentiate between and detect only Ag ions is an important first step to solving the toxicity mystery of AgNPs. Chapter 3 focuses on the development of sensor coatings containing a Eu(III) based luminescent system for sensing dissolved CO2 without the aid of an absorption-based dye. It is well-known that monitoring CO2 levels in our environment is important since even at low concentrations it can cause adverse health effects to the human body. This work demonstrates a pH-sensitive Eu complex being used directly as a CO2 sensor without the aid of any other absorption-based dye. Chapter 4 explores the idea of developing a heavy metal sensor for lead and its ability to detect lead in wide concentration range upon changing the pH of the medium and the …
Date: May 2019
Creator: Benton, Erin Nicole
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Differentiation: A Taxonomy of Online Learner Types in Higher Education (open access)

Differentiation: A Taxonomy of Online Learner Types in Higher Education

Online learning is no longer considered novel within higher education. It has emerged as an accepted distinct channel and environment for instructional engagement. There is a notable deficit of works and theoretical constructs specifically addressing the identification and differentiation of online learner types and examining them as a distinct system within the learning environment. Learning effectiveness within an online instructional environment is affected by the individual student engaged in the instruction. The instructional experience of the learner is determined by their individual perceptions of and reactions to both internal and external factors. Therefore, it is critical to address the online learner holistically as a stand-alone systemic dimension of the online learning environment to truly understand their differentiating behaviors, motives, characteristics, and dynamics. The study classified and articulated the distinctive types of learners engaged in online instruction within the higher education context based on the key dynamics, factors, and influencers of the individual in order to provide a more comprehensive understanding of the individuals engaged in learning. Additionally, the study generated a new theoretical model, the taxonomy of online learner types (TOLT) to provide unique insights into the different types of learners and serve as an essential step towards developing awareness …
Date: May 2019
Creator: Darby, Douglas
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Distance Learning in Singing Education: An Overview of Historical and Modern Approaches and Future Trends (open access)

Distance Learning in Singing Education: An Overview of Historical and Modern Approaches and Future Trends

This research of distance learning in singing study provides some historical framework of long-distance singing study, including research on three former distance singing courses, which exemplify the "best practices" of their time: Siegel-Myers Correspondence School of Music, the Perfect Voice Institute, and the Hermann Klein Phono-Vocal Method: Based Upon the Famous School of Manuel Garcia. I also discuss current trends in long-distance singing study, including interviews and insights from current long-distance singing teachers using cutting edge technology in their virtual studios. Lastly, I make predictions and projections, based on analyses of past "best practices," where this information may have impact upon future methods of distance singing lessons, including conceivable distance singing course components of online degree programs offered at universities.
Date: May 2019
Creator: Wood, Samantha (Soprano)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Eak Tai Ahn's Korea Fantasy: His Life, Historical Context, and Compositional Style (open access)

Eak Tai Ahn's Korea Fantasy: His Life, Historical Context, and Compositional Style

Eak Tai Ahn is not only the first generation of Korean musicians, composers and conductors to have studied Western music and given successful musical performances in Western countries, but also is among the first to introduce the music of Korea to the West utilizing the Western music system. Korea Fantasy is an important work that helped Ahn win international acclaim. Korea Fantasy is an orchestral piece that evolved along with Ahn's unique life experiences shaped by the state of his native country. The piece is programmatic, depicting the history of Korea, which utilizes musical devices, such as rhythms and quotation that are distinctive musical elements of Korea. This document discusses the political and social history of Korea during Ahn's life time, offers an overview of Ahn's education and musical footsteps, and describes the premiere and reception of Korea Fantasy. Moreover, a discussion of his compositional traits and a musical analysis of Korea Fantasy are presented.
Date: May 2019
Creator: Baek, Da Mi
Object Type: Thesis or Dissertation
System: The UNT Digital Library

The Effect of Processing Conditions on the Surface Morphology of Few-Layered WS2 Thin Films

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Recent progress in layered transition metal dichalcogenides (TMDs) has led to various promising electronic and optoelectronic applications. However, the structure of materials plays a critical role in electronic and optoelectronic devices, and determines performance. Electronic and optoelectronic devices typically consist of multiple layers that form electrical homojunctions or heterojunctions. Therefore, in a device it can be expected that a WS2 layer may serve as the substrate for a subsequent layer in a multilayer device stack and determine how the layer grows. In transistor structures, roughness at the channel/gate dielectric interface introduces field variations and charge scattering. Therefore, understanding the relations between processing, surface morphology and properties is important. In this project, the effects of pulsed laser deposition (PLD) processing conditions on the surface morphology of few layered WS2 films were studied. WS2 films were synthesized under processing conditions that represent the extremes of surface supersaturation and kinetic energy transfer from the flux to the growing films, and evolution of the surface morphology was studied. The specific conditions were 1Hz/50mJ, 10Hz/50mJ, 1Hz/300mJ, and 10Hz/300mJ respectively. Combining AFM, XRD and Raman analyses, it was determined that deposition at 10Hz/300mJ, provided the best structural properties and surface morphology. Growth appeared to be 3D-cluster, …
Date: May 2019
Creator: Cai, Bimin
Object Type: Thesis or Dissertation
System: The UNT Digital Library

The Effect of Trauma Experiences and PTSD Severity on Positive Memory Recall and Memory Phenomenology

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Positive memories play an important role in the etiology and maintenance of posttraumatic stress disorder (PTSD). Additionally, there are potential clinical benefits of recalling positive memories on affect, cognitions, and behaviors. However, most research/clinical work has focused on the role of traumatic memories in PTSD's symptomatology and treatment. The current study examined positive memory recall difficulties and positive memory phenomenology among 185 trauma-exposed individuals with varying PTSD severity. Participants completed the Life Events Checklist for DSM-5, PTSD Checklist for DSM-5, Autobiographical Memory Test, Memory Experiences Questionnaire – Short Form, Ruminative Thought Style Questionnaire, Difficulties in Emotional Regulation Scale – Brief 16-Item Version, Difficulties in Emotional Regulation Scale – Positive Emotions, the Positive Affect subscale of the Affective Control Scale, and two items from the Pittsburg Sleep Quality Index. Results showed that (1) greater PTSD severity was a marginally significant predictor of fewer recalled positive memories; (2) greater positive emotional dysregulation predicted fewer recalled positive memories controlling for PTSD severity; and (3) increasing PTSD severity predicted more negative valence, less vividness, less coherence, less accessibility, less clear time perspective, fewer sensory details, and greater distancing ratings of the recalled positive memory, controlling for sleep quantity/quality. Such findings add to the PTSD-positive …
Date: May 2019
Creator: Dolan, Megan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Effects of Common and Uncommon Elements on the Emergence of Simple Discriminations (open access)

The Effects of Common and Uncommon Elements on the Emergence of Simple Discriminations

A computerized program was designed to test whether arranging a common element in two, otherwise independent, 2-term correlations (stimulus-stimulus and response-stimulus) would result in emergent simple discriminative-stimulus properties for the antecedent stimulus relative to an arrangement with no common elements programmed. Data from 8 adult participants in this experiment indicate that common element arrangements led to relatively high rates of responding in the presence of the putative discriminative stimulus and relatively low rates or no responding in the presence of the putative s-delta during testing in extinction. Conversely, the uncommon element arrangements produced no clear discriminative control. The current data reflect a comparison of arrangements across subjects. These data support Sidman's (2000) suggestion that common elements among contingencies are sufficient to produce stimulus classes and cause class mergers. The data also have implications for thinking about the mechanism by which and the conditions under which discriminative control develops. Finally, these data have the potential to inform the programming and implementation of reinforcement contingencies in applied settings.
Date: May 2019
Creator: Niland, Haven Sierra
Object Type: Thesis or Dissertation
System: The UNT Digital Library