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Effect of Makerspace Professional Development Activities on Elementary and Middle School Educator Perceptions of Integrating Technologies with STEM (Science, Technology, Engineering, Mathematics)

Description: This study investigated a Makerspace professional development program, the Makers' Guild, provided to teachers within north Texas over the course of a semester. The research employed a constructionist approach delivered via 2D and 3D technologies during STEM instructional activities within a creative space. Participants reported statistically significant increases in self-reported competence in technology integration, confidence levels toward integrating World Wide Web, Emerging Technologies for Student Learning, Teacher Professional Development, and attitudes toward math, technology, science, and STEM careers.
Date: December 2016
Creator: Miller, Jennifer R
Partner: UNT Libraries

An Evaluation of the Effects of Effort on Resistance to Change

Description: Behavioral momentum theory (BMT) has become a prominent method of studying the effects of reinforcement on operant behavior. BMT represents a departure from the Skinnerian tradition in that it identifies the strength of responding with its resistance to change. Like in many other operant research paradigms, however, responses are considered to be momentary phenomena and so little attention has been paid to non-rate dimensions of responding. The current study takes up the question of whether or not the degree of effort defining a discriminated operant class has any meaningful effect on its resistance to change. Using a force transducer, rats responded on a two-component multiple VI 60-s VI 60-s schedule where each component was correlated with a different force requirement. Resistance to change was tested through prefeeding and extinction. Proportional declines in response rate were equal across components during all disruption tests. Differentiated response classes remained intact throughout. The negative result suggests several future research directions.
Date: December 2016
Creator: Foss, Erica K
Partner: UNT Libraries

Defect Behaviors in Zinc Oxide and Zinc Titanates Ceramics from First Principles Computer Simulations

Description: ZnO and ZnO-TiO2 ceramics have intriguing electronic and mechanical properties and find applications in many fields. Many of these properties and applications rely on the understanding of defects and defect processes in these oxides as these defects control the electronic, catalytic and mechanical behaviors. The goal of this dissertation is to systematically study the defects and defects behaviors in Wurtzite ZnO and Ilmenite ZnTiO3 by using first principles calculations and classical simulations employing empirical potentials. Firstly, the behavior of intrinsic and extrinsic point defects in ZnO and ZnTiO3 ceramics were investigated. Secondly, the effect of different surface absorbents and surface defects on the workfunction of ZnO were studied using DFT calculations. The results show that increasing the surface coverage of hydrocarbons decreased the workfunction. Lastly, the stacking fault behaviors on ilmenite ZnTiO3 were investigated by calculating the Generalized Stacking Fault (GSF) energies using density functional theory based first principles calculations and classical calculations employing effective partial charge inter-atomic potentials. The gamma-surfaces of two low energy surfaces, (110) and (104), of ZnTiO3 were fully mapped and, together with other analysis such as ideal shear stress calculations.
Date: December 2016
Creator: Sun, Wei
Partner: UNT Libraries

A Multidimensional Polymetric Analysis of Excerpts from the Wind Band Music of Dan Welcher and Yo Gotō

Description: Polymetric writing is an integral technique in contemporary compositional practice. Dan Welcher and Yo Goto are principal employers of this practice in the wind band medium. Their methods endure even the results of modern scholarship showing limited human perception of polyrhythmic events. This dissertation provides a comprehensive metric analysis of excerpts from the music of Welcher and Goto. Five examples are explored from major band works of each of the two composers. The analytical process in the study utilizes the metrical concept set forth by Maury Yeston, so that a comparison can be made between the rhythmic components of the competing meters. The results of the study show that both Welcher and Goto, in all ten excerpts, create polymetric sections containing elements that surpass the aural limits proposed by modern scholarship. Additionally, through identification of the misaligned metric layers causing each polymeter, pedagogical considerations are offered to aid performance of each identified excerpt.
Date: December 2016
Creator: Robinson, David
Partner: UNT Libraries

An Evaluation of Correspondence between Preference and Performance under a Progressive Ration Schedule with College Students

Description: Preference assessments are used in clinical settings to identify stimuli with reinforcing potential. The progressive-ratio schedule has shown to be useful in clinical assessments in identifying stimuli with stronger reinforcer efficacy that corresponds to formalized assessments.The current study utilized a progressive-ratio schedule to compare videos of high and low preference assessed by verbal reports of preference with college students. Results indicated breakpoints were higher for high preferred videos than low preferred videos for three out of five participants, but preference was not indicative of performance.
Date: December 2016
Creator: Johnson, Jamarious
Partner: UNT Libraries

Ethiopian Coffee Stories: Applied Research with Sidama Coffee Farmers Combining Visual and Ethnographic Methods

Description: The purpose of this study is to demonstrate the value of visual research methods to applied anthropology in the context of exploratory research with farmers in Ethiopia. The three methods of photo-elicitation, participatory photography, and ethnographic film, enrich and expand ethnographic methods to support the client's objective of supporting farmers. The applied project constructs a narrative from the local perspective to help consumers learn more about farmers' lives. The research focuses on specific farmers, and their experiences with direct fair trade and coffee farming. The client sees the application of research produced by ethnographic and visual methods as a good direction not only for his company, but the Fair Trade Industry as a whole.
Date: December 2016
Creator: Suter, Paula Jean
Partner: UNT Libraries

Dissimilar Friction Stir Welding Between Magnesium and Aluminum Alloys

Description: Joining two dissimilar metals, specifically Mg and Al alloys, using conventional welding techniques is extraordinarily challenging. Even when these alloys are able to be joined, the weld is littered with defects such as cracks, cavities, and wormholes. The focus of this project was to use friction stir welding to create a defect-free joint between Al 2139 and Mg WE43. The stir tool used in this project, made of H13 tool steel, is of fixed design. The design included an 11 mm scrolled and concave shoulder in addition to a 6 mm length pin comprised of two tapering, threaded re-entrant flutes that promoted and amplified material flow. Upon completion of this project an improved experimental setup process was created as well as successful welds between the two alloys. These successful joints, albeit containing defects, lead to the conclusion that the tool used in project was ill fit to join the Al and Mg alloy plates. This was primarily due to its conical shaped pin instead of the more traditional cylindrical shaped pins. As a result of this aggressive pin design, there was a lack of heat generation towards the bottom of the pin even at higher (800-1000 rpm) rotation speeds. This lack of heat generation prohibited the material from reaching plastic deformation thus preventing the needed material flow to form the defect free joint.
Date: December 2016
Creator: Reese, Gregory A
Partner: UNT Libraries

Maternal Transfer of Dietary Methylmercury and Implications for Embryotoxicity in Fathead Minnows (Pimephales promelas)

Description: Mercury (Hg) is a ubiquitous environmental contaminant, which is capable of global atmospheric transport. As a result, even the most pristine aquatic ecosystems are affected by atmospheric Hg deposition, following which microbial transformation yield organic Hg forms, the most concerning of which is methylmercury (MeHg). Methylmercury is capable of bioaccumulation and biomagnification in food webs, resulting in potentially toxic body burdens due to regular dietary exposure in long-lived organisms at higher trophic levels. It is also a molecular mimic of some endogenous amino acids, providing a route of transfer from mother to offspring via large amino acid transporters. Exposure during neurodevelopment can lead to serious, irreversible neurological dysfunction, associated with a variety of cognitive and motor abnormalities across species. The present studies evaluate the effects of maternally-transferred dietary MeHg, at environmentally relevant concentrations on early life stage fathead minnows (Pimephales promelas). Embryos were collected from adult fatheads exposed to one of three diets with varying concentrations of MeHg for 30 days. Adult reproductive metrics were also monitored over the course of the study, with results indicating no effects on spawning frequency, clutch size, or total egg output. In embryos, Hg concentration was a function of female diet and the duration (number of days) of female exposure. Offspring spawned in tanks administered the low Hg diet displayed altered embryonic movement patterns (hyperactivity), decreased time to hatch, decreased mean larval size, and alterations to several metabolite abundances when compared with controls. Significantly altered metabolites include those associated with cellular energetics, fatty acid metabolism, and polyamine synthesis, indicating current environmental exposure scenarios are sufficient to disrupt important cellular pathways. Dysregulation of the dopaminergic system of embryos is also characterized, and may be a possible mechanism by which hyperactive behaviors are observed in these embryos. Offspring from tanks administered the high Hg diet exhibited ...
Date: December 2016
Creator: Bridges, Kristin
Partner: UNT Libraries

Western Spruce Budworm Effects on Throughfall C, N, and P Fluxes in a Central Washington Forest

Description: Western spruce budworm (Choristoneura occidentalis) outbreaks periodically disturb Western US conifer forests by defoliating canopies, which could alter the quantity and chemistry of throughfall delivered to the forest floor. Our objectives were to: i) quantify throughfall water, carbon (C), nitrogen (N), and phosphorus (P) fluxes under budworm-impacted canopies, and ii) examine the influence of herbivore intensity on flux magnitudes. In June 2015, we installed throughfall collectors in two watersheds experiencing high and background levels of herbivory. In each watershed, four plots, each with three throughfall collectors, were established (n=24) collectors), and two bulk rainfall collectors were installed in areas without canopy cover. Throughfall and rainfall were collected from late June to early November 2015. Samples were analyzed for dissolved organic carbon (DOC), ammonium (NH4-N), and soluble reactive phosphorus (SRP). Over the sampling period, throughfall fluxes ranged 8.57 to 47.59 kg/ha for DOC, 0.004-0.011 kg/ha for NH4-N, and 007 - 0.29 kg/ha for SRP. Percent throughfall was slightly, but not significantly, higher in the high (48%) compared to the background watershed (42%). There were no differences in solute concentrations among the watersheds. Net throughfall fluxes, the sum of canopy uptake and leaching and dry/fog deposition, differed significantly for NH4-N by herbivory level and through time for NH4-N and DOC but not SRP. Over time, net NH4-N throughfall fluxes showed a clear transition from net uptake of NH4-N to net leaching of NH4-N in the high herbivory watershed. There was also a clearn NH4-N pulse in the high herbivory watershed after the first, but not subsequent, rainfall events. In this N-limited forest, altered throughfall N may affect soil nutrient cycling and downstream water quality.
Date: December 2016
Creator: Bailey, Jennifer Meghan
Partner: UNT Libraries

Negotiated Living: An Ethno-Historical Perspective of Punta Allen

Description: Situated within the jurisdiction of the Municipality of Tulum and within the Sian Ka'an Biosphere gives the village of Punta Allen a distinctive agency in determining their role in the on-going development of tourism in the region that is not given to other communities in the state. This unique circumstance facilitates a dialogue between the reserve, the municipality, and the business cooperatives of Punta Allen that produce a negotiated living. Through the negotiations with the reserve and Tulum, the lobster fishing and tourism cooperatives are given the opportunity to have a relatively significant role in determining the future of Punta Allen in regards to tourism.
Date: December 2016
Creator: McRae, David Thomas
Partner: UNT Libraries

A Decomposition of the Group Algebra of a Hyperoctahedral Group

Description: The descent algebra of a Coxeter group is a subalgebra of the group algebra with interesting representation theoretic properties. For instance, the natural map from the descent algebra of the symmetric group to the character ring is a surjective algebra homomorphism, so the descent algebra implicitly encodes information about the representations of the symmetric group. However, this property does not hold for other Coxeter groups. Moreover, a complete set of primitive idempotents in the descent algebra of the symmetric group leads to a decomposition of the group algebra as a direct sum of induced linear characters of centralizers of conjugacy class representatives. In this dissertation, I consider the hyperoctahedral group. When the descent algebra of a hyperoctahedral group is replaced with a generalization called the Mantaci-Reutenauer algebra, the natural map to the character ring is surjective. In 2008, Bonnafé asked whether a complete set of idempotents in the Mantaci-Reutenauer algebra could lead to a decomposition of the group algebra of the hyperoctahedral group as a direct sum of induced linear characters of centralizers. In this dissertation, I will answer this question positively and go through the construction of the idempotents, conjugacy class representatives, and linear characters required to do so.
Date: December 2016
Creator: Tomlin, Drew E
Partner: UNT Libraries

Teaching Water Safety Skills to Children with Autism Using Behavioral Skills Training

Description: Behavioral skills training (BST) and in situ training (IST) have been evaluated as methods to teach different safety skills to individuals with developmental disabilities. Research on BST has examined topics such as gun safety, abduction prevention, poison avoidance, and sexual abuse prevention. A large safety issue that is missing from the literature is drowning prevention and water safety skills. Drowning is one of the most prevalent issues facing facing children with Autism Spectrum Disorder (ASD), particularly those who elope from their homes or caregivers. The current study aimed the effectiveness of using BST+IST to teach three water safety skills to three children with ASD. The intial form of intervention was BST with total task presentation of the skill, using verbal instruction, modeling, rehearsal, and feedback. If this intervention did not result in an increase in performance, the skill was broken down into individual component presentation, in which each component of the skill was taught using the same procedures. Results from the current study showed that BST+IST was effective in teaching all skills to all participants.
Date: December 2016
Creator: Tucker, Marilyse
Partner: UNT Libraries

Ion Beam Synthesis of Binary and Ternary Transition Metal Silicide Thin Films

Description: Among the well-known methods to form or modify the composition and physical properties of thin films, ion implantation has shown to be a very powerful technique. In particular, ion beam syntheses of binary iron silicide have been studied by several groups. Further, the interests in transition metal silicide systems are triggered by their potential use in advanced silicon based opto-electronic devices. In addition, ternary silicides have been by far less studied than their binary counterparts despite the fact that they have interesting magnetic and electronic properties. In this study, we investigate ion beam synthesis of Fe-Si binary structures and Fe-Co-Si ternary structures. This work involves fundamental investigation into development of a scalable synthesis process involving binary and ternary transitional metal silicide thin films and Nano-structures using low energy ion beams. Binary structures were synthesized by implanting Fe- at 50 keV energy. Since ion implantation is a dynamic process, Dynamic simulation techniques were used in these studies to determine saturation fluences for ion implantation. Also, static and dynamic simulation results were compared with experimental results. The outcome of simulations and experimental results indicate, dynamic simulation codes are more suitable than static version of the TRIM to simulate high fluence, low energy and, heavy ion implantation processes. Furthermore, binary Fe-Si phase distribution was determined at different implantation fluences and annealing temperatures. A higher fluence implantation at 2.16×1017 atoms/cm2 and annealing at 500 oC showed three different Fe-Si phase formations (β-FeSi2, FeSi and Fe3Si) in substrate. Further, annealing the samples at 800 oC for 60 minutes converted the Fe3Si phase into FeSi2 and FeSi phases. As an extension, a second set of Fe- ion implantations was carried with the same parameters while the substrate was placed under an external magnetic field. External magnetic fields stimulate the formation of magnetic phase centers in the ...
Date: December 2016
Creator: Lakshantha, Wickramaarachchige Jayampath
Partner: UNT Libraries

Analysis of Students' Knowledge, Perceptions, and Interest in Engineering Post Teacher Participation in a National Science Foundation (NSF) Research Experience for Teachers (RET) Professional Development

Description: This study examined the impact of the National Science Foundation's Research Experience for Teachers (RET) in engineering at University of North Texas on students after their teachers' participation in the program. Students were evaluated in terms of self-efficacy, knowledge of engineering, perceptions of engineering, and interest in engineering. A 22-item Likert pre/post survey was used for analysis, and participants included 589 students from six high schools, one middle school, and one magnet school. Paired surveys were analyzed to determine if there was a statistically significant difference in attitudes and knowledge after teachers implemented lessons from their time at the RET. Surveys were also analyzed to determine if there was a statistically significant difference in student response based on gender or student school type. Results showed no statistically significant difference in the self-efficacy of students, however there was a statistically significant difference in knowledge, perceptions, and interest in engineering. In addition, there was a statistically significant difference between genders on an isolated question, and seven out of the 22 Likert questions showed a statistically significant difference between student school types.
Date: December 2016
Creator: Reeder, Christina
Partner: UNT Libraries

Modeling of Fracture Toughness of Magnesium Alloy WE43 Before and After Friction Stir Processing

Description: Magnesium alloys are a popular research topic for structural applications because they have a lower density than conventional structural materials, including steel, titanium, and aluminum; however, the reliability and safety of their mechanical properties must be further proven. An important mechanical property for this purpose is fracture toughness, which is the measure of the material's resistance to crack propagation. In this study, a model of an experiment to investigate the fracture toughness of a magnesium alloy WE43 before and after friction stir processing (FSP) is developed, and the results are compared to those produced by a digital image correlation (DIC) system during an experiment from another paper. The model results of the material before FSP matched well with the DIC results, but the model of the material after FSP only partially matches the DIC results. In addition, a theoretical approach to calculating the standard fracture toughness value, KIc, from the modeling results is proposed, and is found to be a conservative approach.
Date: December 2016
Creator: Lipscomb, Celena Andrea
Partner: UNT Libraries

Women Chief Housing Officers at State Universities in the Northwest United States

Description: Hyatt, Jennifer Leigh. Women Chief Housing Officers at State Universities in the Northwest United States. Doctor of Education (Higher Education), December 2016, 89 pp., 1 table, 3 figures, 48 references, titles. This qualitative study explored the experiences of women chief housing officers (CHOs) at state universities within the northwest region of the United States. The study used narrative inquiry methodology with a thematic analysis approach to investigate how seven female CHOs experience and make meaning of their professional career progression and journey toward becoming and remaining a CHO. Five core themes emerged from the study: (a) understanding housing operations, (b) self-efficacy, (c) gender inequities, (d) relationships with staff, and (e) mentorship. The theme of gender identity suggests that gender does influence how these female CHOs make meaning of their professional experience. The overall results suggest that although the perception of many is that the field of student affairs is wide open to women, in some senior-level positions, such as CHO, gender inequity is prevalent. A factor that may contribute to this inequity is the privatization of housing which calls for a greater understanding of business and housing operations, areas dominated by males. An implication from this study is that an increase in the number of women in the CHO position may only occur when university housing personnel expand professional preparation for mid-level housing positions to include more business-related practices. The mid-level position could then be seen as a step toward desired CHO competencies and toward making the position of CHO more inclusive.
Date: December 2016
Creator: Hyatt, Jennifer
Partner: UNT Libraries

Unclean Slates: Stories

Description: Unclean Slates: Stories is a collection of seven short stories that comments on the nature of family ties, and how such ties help form a sense of identity. Each story focuses on a separate protagonist, all of whom strive for a new beginning or an escape from some aspect of their current lives. The short story cycle of this collection is held together not by place or characters, but ultimately by the theme of wishing for a new beginning: they share a desire to fix some dissatisfying element of their lives. Mostly from the point of view of blue-collar characters leading mundane middle-class lives, these stories provide commentary on what it means to run from the conditions that make up one's sense of identity. Most of the revelations formed throughout these stories lead to a sense of acceptance of these conditions, and an understanding that family and history make up part of human consciousness. While the specific locations presented in these stories are not necessarily the same, each story seeks to focus on a location that proves to be fundamental to the makeup of the protagonist. The cities and geographic locations themselves are not as important as the specifics: the schools, diners, lakes, and so forth where these characters find themselves contemplating their disillusionment about where their lives have brought them. Facing everything from postpartum depression to simply missing out on a career opportunity, these characters all experience a sense of loss that brings them together in a way that is recognizable to the reader as the collection progresses.
Date: December 2016
Creator: Gollahon, Catherine
Partner: UNT Libraries

Creating a Verbal Community for Describing Emotional Responses within a Contingency Lens: The Effects of a Brief Training Workshop

Description: Observing emotional responses is recognized as a valuable clinical skill in a variety of professions, including applied behavior analysis. Emotional responses can flag possible contingencies thereby guiding a behavior analyst to better select valid measures, goals, and procedures. Additionally, emotional responses can be goals in and of themselves. The purpose of the present study was to evaluate the effects of a workshop on the observation and description of emotional responses by behavior analysts-in-training. The procedures included instructions, modeling, practice, discussion and feedback. The workshop included a blend of trainer presentation and interteaching strategies. The effects of the workshop were evaluated using a single-subject A-B design with multiple probe measures across four students. During probe assessments participants watched short video clips of family interactions and wrote a descriptive narrative in response to several questions. This created a permanent record for quantitative evaluation and analysis. The study resulted in an increase in the number of descriptions of emotional responses among all participants. The participants also increased responses tying the emotional response to external environmental events more often in the post-workshop assessment than the pre-workshop assessment. Results are discussed within the context of training applied behavior analysts, the analysis of verbal behavior, and the role of emotions in clinical practice.
Date: December 2016
Creator: Garden, Regan E.
Partner: UNT Libraries

Using Situated Learning, Community of Practice, and Guided Online Discourse in Healthcare Education for Learning Effective Interprofessional Communication

Description: The problem exists that there are no education initiatives focused on teaching and taking into practice the skills of effective interprofessional discourse in this online, asynchronous, professional environment. The purpose of this study was to examine whether it is possible for students in the health professions to learn to practice effective interprofesssional online discourse in an electronic health record. This was a mixed methods study that included both quantitative ad qualitative inquiry underpinned by post positivism and used a method triangulation research design model. Both quantitative and qualitative data were collected and analyzed from an educational intervention and simulated electronic health record exercise. The students' perceptions of their practice in an electronic health record did not necessarily match their knowledge and skills in this group of students. Emergent themes from the study pointed in the possible direction of perceived value of the exercise, prior experience in an electronic health record, and logistical barriers to the activity. Perceived time constraints was a particularly strong concern of the students. The emergent themes might be valuable considerations for other interprofessional programs looking to implement similar activities concerning the electronic health record.
Date: December 2016
Creator: Krumwiede, Kimberly A.H.
Partner: UNT Libraries

Academic Progress Scores to Predict Performance on a State Assessment

Description: This quantitative study examined seventh-grade reading scores to determine the extent to which certain demographic variables (race/ethnicity, gender, socioeconomic status) explain and MAP reading scores predict reading scores on the State of Texas Assessment of Academic Readiness (STAAR) in a selected northeast Texas public school. Standardized assessments only compare the relative performance of an individual student to other groups of students using scaled scores, which can vary from year to year and from state to state. With the advent of computer adaptive testing, this study provides information on the predictive validity of benchmark assessments. Specifically, this study looked for predictive evidence that indicates how accurately test data can predict criterion scores. Findings revealed, through a multiple regression analysis, that the fall MAP Rasch Unit (RIT) scores predicted the STAAR scale scores. Using SPSS version 22, the data were entered and analyzed in a multiple regression model to determine the presence of a statistical trend or lack thereof. Demographic data and MAP scores were entered into the regression model to examine the predictive validity of the MAP assessment in determining student performance on the STAAR seventh-grade state-mandated reading assessment. The statistical analysis revealed that MAP RIT scores explain a significant variance related to seventh-grade STAAR reading scale scores. There is a vital need for tools that improve a student's academic development and MAP assessments have been found to predict performance on state-mandated assessments.
Date: December 2016
Creator: Curry, David Mitchell
Partner: UNT Libraries

The Social Psychology of Social Media Reactions to Terrorism

Description: Columnists and social media users commonly stated that terrorist attacks resonate differently in the world and they speculated on some potential reasons such as familiarity, number of victims, and the difference in expectations of a country to be a stage for a terrorist attack to explain this difference. An academic perspective, more specifically a sociological one, is needed to bring light to this debate. In this study, I aimed to understand the discourse after terrorist attacks and to find out if there is a difference between reactions to terrorist attack based on where they happened. This paper embraces a text mining approach to uncover what topics are discussed after four cases of terrorist attacks and to reveal if there is a discrepancy in reactions towards terrorist attacks based on the country they happened. The study consists of two parts. In the first part, the determinants of the public interest and support and how public interest differentiates between different cases of terror attacks is explored. In the second part, topic sentiment analysis is conducted to reveal the nature of the discourse on terrorism. Using the insights from social identity theory, realistic conflict theory and integrated threat theory, I argued that social group categorization in the context of terrorism takes place in a dichotomous manner as Western and Non-Western. This argument, social self-identities being based on ‘West vs. the Rest' mentality in the context of terrorism, is supported by the statistical evidence and the topic model. Theoretical and practical implications are discussed.
Date: December 2016
Creator: Demirhan, Emirhan
Partner: UNT Libraries

The Strength of a Witness: Empowerment and Resiliency in the Aftermath of Atrocity

Description: Victims and witnesses that testify before an international criminal tribunal such as the International Criminal Tribunal for the Former Yugoslavia (ICTY) willingly subject themselves to scrutiny and bare their wounds before the world. Does this experience cause these vulnerable individuals undue psychological harm, re-traumatization, or worse? Existing literature indicates this may be the case, however using a new dataset I find the opposite to be true. Witnesses at the ICTY report feeling more positive than negative after their experiences on the stand. As the first systematic study on witness mental wellbeing, these findings contradict expectations found in previous research.
Date: December 2016
Creator: McKay, Melissa
Partner: UNT Libraries

The Influence of Population on Wrongful Convictions

Description: With criminal cases continuing to be exonerated across the United States, research must be done on the subject to advance current practices to reduce its occurrence in the future. This study combines county population data with the National Registry of Exonerations to analyze the contributing factors to wrongful convictions and the possible effect of population on their frequency. The objective of this study was to identify specific policy changes based on the five contributing factors to wrongful convictions that could be applied to population specific areas. The results yielded multiple patterns that are discussed thoroughly. These findings allowed the introduction of policy changes and proposals for future research.
Date: December 2016
Creator: Whittington, Kari
Partner: UNT Libraries

Cardiovascular Fetal Programming in Quail (Colinus virginianus), An Avian Comparative Model

Description: The consequences of early embryonic insults and how they affect subsequent life reflects the emerging concept of "fetal programming". The aim of this project is to study the effects of embryonic insults as they subsequently manifest themselves in adults, with emphasis on the heart and vasculature. My experiments establish that fetal programming operates on the bobwhite quail inducing similar changes as those observed in mammalians and other birds. The quail's fast development provides reliable data in a short period of time than other avian models (e.g. domestic chicken). Data on quail showed a correlation between egg mass and hatchling mass; where small eggs produce small hatchlings but a high mortality made it impractical as a stressor for this study. Hypoxia was used as a stressor during embryonic incubation, where it induced a low hatching weight in quail that was not observable in adult birds. Morphological measurements demonstrated an increased ventricular collagen content and reduced ventricular lumen in birds in adults incubated in hypoxia consistent with hypertension. The hematological analyzes showed few differences indicating organ remodeling instead of hematopoietic compensation. The assessment of vascular reactivity pointed out an impaired endothelium dependent relaxation commonly associated to hypertension in birds and mammals. Fetal programming could be a widespread response to an adverse prenatal environment in endotherms and the resulting data from this work contributes to our understanding of fetal programming in vertebrates and its long term consequences.
Date: December 2016
Creator: Flores Santin, Josele
Partner: UNT Libraries