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Adolescents' Social Networking Use and Its Relationship to Attachment and Mental Health
Adolescents spend much of their time using the internet and electronic media. Since its inception, the use of online social networking (OSN) sites by adolescents continues to grow. With the proliferation of OSN, it is critical to examine how this activity affects psychological development, but better measurement tools are needed. As researchers struggle to keep up with this rapidly growing field, many gaps remain in the literature investigating the interrelations between adolescent's OSN use and mental health outcomes. Research examining the relationship between OSN and mental health outcomes, specifically depression and anxiety, has produced mixed results suggesting that other factors influence this association. A large research literature documents associations between attachment and mental health. Given that attachment also affects interpersonal communication, several studies have investigated links between attachment and OSN use in adult and college populations. Results indicated that even though attachment to father was independently related to anxiety and depression symptoms, it was not a significant moderator for mental health and OSN. Attachment to mother was a significant moderator for anxiety and depression and several OSN subscales. Based on this information, a greater focus on youth's interpersonal connection and social skills both online and offline may be beneficial when treating adolescents experiencing anxiety or depression.
The Story of Pathfinders [Family Pathfinders]: Investigating the Impact, Experiences, and Context of Re-Entry Mentoring
The United States has the largest population of imprisoned persons in the world. The vast majority of these individuals eventually leave prison and re-enter society, facing a number of challenges in the process. Those who are unable to successfully re-enter society run the risk of recidivating back into the prison system. Mentoring has the potential to promote successful re-entry and help offenders to get their lives back on track. Pathfinders of Tarrant County is a unique organization. Its historical position as one of the foremost "welfare to work" programs gives it unique insight into the economic struggles of at-risk individuals and families, and its existing relationships with mentors and other community organizations gives it a rich pool of resources to draw from. By helping to connect participants with community resources, Pathfinders removes quite a bit of the complexity from seeking help at a time when vulnerable people need it most. This thesis presents an overview of how Pathfinders conducts mentoring and its unique brand of social service advocacy, including the unique and not-so unique challenges that a re-entry population may have to offer.
Drought: Construction of a Social Problem
Drought is a complex subject that has varied definitions and perspectives. Although drought has historically been characterized as an environmental problem from both the meteorological and agricultural communities, it is not considered a sociological disaster despite its severe societal impacts. Utilizing the framework developed by Spector and Kitsuse (2011) and Stallings (1995), this research examines the process through which drought is defined as a social problem. An analysis of the data revealed drought was well covered in Africa, India, China, Australia, and New Zealand, yet very little coverage focused on the United States. There were less than 10 articles discussing drought and drought impacts in the United States. The workshops/meetings examined also were lacking in the attention to drought, although their overall theme was focused on hazards and resilience. Six sessions in over 16 years of meetings/workshops focused on the topic of drought, and one session was focused on the condition in Canada. The interviews uncovered five thematic areas demonstrating drought understanding and awareness: Use of outreach to get the message out; agricultures familiarity with drought; the role of drought in media; the variability of what drought is; and water conservation. Drought's claims-makers who are dedicated to providing outreach and education to impacted communities. Drought is often overlooked due to its slow onset and evolving development makes it difficult to determine when to engage in recovery efforts. Drought defined as a social problem also expands theoretical conversations regarding what events or issues should be included within the sociological disaster list of topics.
Increasing Number of Toys: A Case Study of Response Generalization across Novel Toys
Children diagnosed with autism are often described as having limited or restricted activities that serve as reinforcers as compared to neurotypical peers. Many theories suggest that one of the many ways children develop is through participation in play. This results in children coming into contact with new environmental stimuli. The procedures used to enhance play skills for children diagnosed with autism typically involve training novel responses with novel stimuli (e.g., toys). This is often done using naturalistic procedures. Because multiple procedures are used, it is unclear what procedure or combination of procedures causes the increases in play repertoires. This study investigated an important component of the treatment package know as reciprocal imitation training. Specifically, the study examined whether increased opportunities, contingent imitation without the requirement to imitate, or contingent imitation with the requirement to imitate would increase the number of toys a child diagnosed with autism would play with. The results showed dramatic increases in the number of toys the child independently chose to play with and an increase in the spontaneous use of different response topographies across novel stimuli only when the student was required to imitate a model. The results are discussed in terms of mediated generalization, the use of common responses, stimulus class formation and stimulus class expansion.
Characterization of Aprotic Solutes and Solvents using Abraham Model Correlations
Experimental data were obtained for the computation of mole fraction solubilities of three dichloronitrobenzenes in organic solvents at 25oC, and solubility ratios were obtained from this data. Abraham model equations were developed for solutes in tributyl phosphate that describe experimental values to within 0.15 log units, and correlations were made to describe solute partitioning in systems that contain either "wet" or "dry" tributyl phosphate. Abraham model correlations have also been developed for solute transfer into anhydrous diisopropyl ether, and these correlations fit in well with those for other ethers. Abraham correlations for the solvation of enthalpy have been derived from experimental and literature data for mesitylene, p-xylene, chlorobenzene, and 1,2-dichlorobenzene at 298.15 K. In addition, the enthalpy contribution of hydrogen bonding between these solutes and acidic solvents were predicted by these correlations and were in agreement with an established method. Residual plots corresponding to Abraham models developed in all of these studies were analyzed for trends in error between experimental and calculated values.
Commissioning Music for Trombone and Percussion: A Collaboration Between Composer and Performer with an Accompanying Survey of Trombone and Percussion Repertoire
The repertoire for trombone and percussion has grown in popularity since the later 1980s. There are currently more than 110 pieces written for the ensemble. This project follows the commissioning and collaboration of Dr. Blake Tyson, Professor of Percussion at the University of Central Arkansas and well known percussion composer, in the creation of a new piece for trombone and percussion. The project also created a survey of works for trombone and percussion duet that includes 32 works. The survey includes details such as specific percussion instrumentation range, tessitura, grade level, publisher, and a description of each piece.
STEM Professional Volunteers in K-12 Competition Programs: Educator Practices and Impact on Pedagogy
This mixed methods dissertation study explored how secondary school educators in specific K-12 competition programs recruited and deployed STEM professional volunteers. The study explored which practices were viewed as most important, and how practices related to constructivist pedagogy, all from the viewpoint of educators. The non-positivist approach sought new knowledge without pursuing generalized results. Review of the literature uncovered extensive anecdotal information about current practices, and suggested that large investments are made in engaging volunteers. One National Science Foundation-sponsored study was identified, and its recommendations for a sustained research agenda were advanced. Three study phases were performed, one to explore practices and operationalize definitions, a second to rate practice's importance and their relation to pedagogy, and a third to seek explanations. Educators preferred recruiting local, meaning recruiting parents and former students, versus from industry or other employers. Most educators preferred volunteers with mentoring skills, and placing them in direct contact with students, versus deploying volunteers to help with behind-the-scenes tasks supporting the educator. Relationships were identified between the highest-rated practices and constructivism in programs. In STEM professional volunteers, educators see affordances, in the same way a classroom tool opens affordances. A model is proposed which shows educators considering practicality, pedagogy, knowledge and skills, and rapport when accessing the affordances opened by STEM professional volunteers. Benefits are maximized when programs align with strong industry clusters in the community.
The Museum is the Object: An Action Research Study in How Critical Theory Curriculum Influences Student Understanding of an Art Museum
The purpose of this action research study was to determine how a critical theory curriculum implemented in a college-level art appreciation course impacted student understanding of an encyclopedic art museum. A critical theory-based curriculum unit was designed and implemented, and students were given assignments to assess their learning. The most significant assignment centered on a self-guided student visit to the art museum in which students made detailed observations of the museum spaces and responded to articles critiquing museum practices. These documents, together with class discussions and my personal observations, were analyzed and described in this research study. The data revealed that students had a high level of regard for and interest in art museums, were capable of understanding how history and context influences museum practices, detected multiple instances of bias in art museum galleries, and self-reported high levels of cognition and empowerment based on their experiences. The data suggested that, in college students, both art appreciation instructors and museum educators have an ideal audience in which to facilitate sustained, higher-level, critical theory-based museum learning experiences.
Adult Learning: Evaluation of Preferences for Technology and Learning Sources for Workplace Learning
The purpose of this research was to provide an initial investigation of the preferences for both technology and learning sources that are available today in the modern workplace at a large financial institution with a national presence in the USA. In addition to the preferences of the participants, the research includes insights about the culture of the learning organization by using the Dimension of Learning Organization Questionnaire (DLOQ) and two preference surveys. The research methods used in this study are categorized as mixed methods and include both quantitative and qualitative methods. This study is nonpositivist and descriptive. It is based on a triangulation design method which is comprised of analysis from data obtained from the DLOQ and preference surveys, as well as semi-structured interviews with several survey participants. The results of the studies provide the foundational information for an extended quantitative analysis.
Framework to Evaluate Entropy Based Data Fusion Methods in Supply Chain Management
This dissertation explores data fusion methodology to deduce an overall inference from the data gathered from multiple heterogeneous sources. Typically, if there existed a data source in which the data were reliable and unbiased, then data fusion would not be necessary. Data fusion methodology combines data form multiple diverse sources so that the desired information - such as the population mean - is improved despite redundancies, inaccuracies, biases, and inflated variability in the data. Examples of data fusion include estimating average demand from similar sources, and integrating fatality counts from different media sources after a catastrophe. The approach in this study combines "inputs" from distinct sources so that the information is "fused." Another way of describing this process is "data integration." Important assumptions are 1. Several sources provide "inputs" for information used to estimate parameters of a probability distribution. 2. Since distributions for the data from the sources are heterogeneous, some sources are less reliable. 3. Distortions, bias, censorship, and systematic errors may be more prominent in data from certain sources. 4. The sample size of sources data, number of "inputs," may be very small. Examples of information from multiple sources are abundant: traffic information from sensors at intersections, multiple economic indicators from various sources, demand data for product using similar retail stores as sources, polling data from various sources, and disaster count of fatalities from different media sources after a catastrophic event. This dissertation seeks to address a gap in the operations literature by addressing three research questions regarding entropy base data fusion (EBDF) approaches to estimation. Three separate, but unifying, essays address the research questions for this dissertation. Essay 1 provides an overview of supporting literature for the research questions. A numerical analysis of airline maximum wait time data illustrates the underlying issues involved in EBDF methods. This ...
Simulink Based Modeling of a Multi Global Navigation Satellite System
The objective of this thesis is to design a model for a multi global navigation satellite system using Simulink. It explains a design procedure which includes the models for transmitter and receiver for two different navigation systems. To overcome the problem, where less number of satellites are visible to determine location degrades the performance of any positioning system significantly, this research has done to make use of multi GNSS satellite signals in one navigation receiver.
Musical Ekphrasis in the Poetry of Nicolás Guillén, Federico García Lorca, and Langston Hughes
Musical ekphrasis was occurring in the twentieth century in different centers around the world, Cuba: Andalusia, Spain; and Harlem, New York, simultaneously. The writers at the heart of this movement used poetry about music as a means to celebrate the cultures of the marginalized people in their lands, los negros, los gitanos, and African-Americans. The purpose of this study is to define musical ekphrasis and identify it in the works of Nicolás Guillén, Federico García Lorca, and Langston Hughes. Also explored are the common characteristics in ekphrastic poetry by the three poets and the common themes found in their ekphrastic poetry, as well as common influences. Each author is considered in the context of his surroundings and his respective culture, and how that influenced his musical tastes as well as his writing style.
Associations between Collaborative Learning and Personality/Cognitive Style among Online Community College Students
This research study investigated associations between online community college students' personal characteristics and experiences in online courses (n = 123). Specifically, students' personalities and cognitive styles were examined alongside the perceived quality and outcomes of collaboration. Negative correlations were found between the conscientiousness personality style and both the quality of collaboration (p = .09) and the outcome of collaboration (p = .05). This finding indicates that conscientious students who, according to the literature tend to have higher academic achievement than other students, perceive negative experiences in online collaborative environments. Conversely, a positive correlation was discovered between the extraversion personality type and the perceived outcomes of collaboration (p = .01). Thus, students with a strongly extraverted personality tend to perceive that they benefits from collaborative learning. Approximately 11% of the variance in the collaborative experience was explained by the combined personal characteristics. The reported frequency of collaboration was positively correlated with both the quality (p < .01) and the outcomes of collaboration (p < .01). While not generalizable, these results suggest that not all students perceive benefits from online collaborative learning. It may be worthwhile to teach students traits associated with the extraversion type like flexibility which is important for collaborative learning. Also, teaching students to adopt traits associated with conscientiousness that improve academic achievement like self-regulation may help improve perceptions of collaborative experiences.
Assessing the Older Diabetic Population in the US: A Descriptive Look at This Population from 2001-2010 Focusing upon Education and Clinical Behaviors
The focus of this research study was to gain needed information on the older adult population in the United States who have diabetes. The research method was quantitative retrospective study of American diabetes obtained from the National Health Interview Survey database from 2001 through 2010. The study results confirmed more than one-third of the U.S. diabetics are aged 65 and older. More than 75% of the older diabetic population report clinical limitations or comorbidities. Based on surrogate markers of education, it appears the older diabetic cohort did receive more preventative care visits than did the older nondiabetic population; however, the difference was not robust. I found a slight negative trend between age and emergency room visits in the older diabetic population; in addition, there was a negative association between age and smoking in this population. There continues to be a need for scientific research in this population. Greater numbers need education and more clinical trials specific to the older diabetic should be encouraged.
Can Observing Behavior Predict Performance in Conditional Discriminations?
Prompts are implemented often in training procedures, to include conditional discriminations, and this can lead to prompt dependency. The current study extends a prior study that suggested that the effectiveness of supplementary visual stimuli displaying the sample and comparison was dependent on the timing in relation to the selection task, presented as a prompt or feedback, in a match-to-sample procedure. The current research examines if the differences in that effectiveness were due to differences in observing behavior in those two conditions. Measures of observing behavior were determined by making access to the individual visual stimuli contingent on clicking on the visual stimulus and keeping the cursor located on the stimulus. Participants viewed the sample comparison much less than the comparison stimulus in both the prompt and feedback conditions. Latency to select the comparison stimulus was much shorter for the prompt condition suggesting that the participants might have interacted differently with the selection task in the two conditions.
An Evaluation of the Effects of Effort on Resistance to Change
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.
Defect Behaviors in Zinc Oxide and Zinc Titanates Ceramics from First Principles Computer Simulations
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.
A Multidimensional Polymetric Analysis of Excerpts from the Wind Band Music of Dan Welcher and Yo Gotō
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.
An Evaluation of Correspondence between Preference and Performance under a Progressive Ration Schedule with College Students
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.
Ethiopian Coffee Stories: Applied Research with Sidama Coffee Farmers Combining Visual and Ethnographic Methods
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.
Dissimilar Friction Stir Welding Between Magnesium and Aluminum Alloys
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.
Maternal Transfer of Dietary Methylmercury and Implications for Embryotoxicity in Fathead Minnows (Pimephales promelas)
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 ...
Western Spruce Budworm Effects on Throughfall C, N, and P Fluxes in a Central Washington Forest
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.
Effects of Brain Brain Injury on Primary Cilia of Glial Cells and Pericytes
Glial cells maintain homeostasis that is essential to neuronal function. Injury to the nervous system leads to the activation and proliferation of glial cells and pericytes, which helps to wall off the damaged region and restore homeostatic conditions. Sonic hedgehog is a mitogen which is implicated in injury-induced proliferation of glial cells and pericytes. The mitogenic effects of sonic hedgehog require primary cilia, but the few reports on glial or pericyte primary cilia do not agree about their abundance and did not address effects of injury on these cilia. Primary cilia are microtubule-based organelles that arise from the centrosome and are retracted before cells divide. Depending on cell type, proteins concentrated in cilia can transduce several mitotic, chemosensory, or mechanosensory stimuli. The present study investigated effects of stab wound injury on the incidence and length of glial and pericyte primary cilia in the area adjacent to the injury core. Astrocytes, polydendrocytes and pericytes were classified by immunohistochemistry based on cell-type markers. In normal adult mice, Arl13b immunoreactive primary cilia were present in a majority of each cell type examined: astrocytes, 98±2%; polydendrocytes, 87±6%; and pericytes, 79±13% (mean ± SEM). Three days post-injury, cilium incidence decreased by 24% in astrocytes (p< 0.008) and 41% in polydendrocytes (p< 0.002), but there was no significant effect in pericytes. Polydendrocytes labeled with the cell cycle marker Ki67 were less likely to have cilia compared to resting, Ki67- polydendrocytes. Considering post-injury rates of proliferation for astrocytes and polydendrocytes, it appears that resorption of cilia due to cell cycle entry may account for much of the loss of cilia in polydendrocytes but was not sufficient to account for the loss of cilia in astrocytes. Under normal conditions, astrocytes rarely divide, and they maintain non-overlapping territories. However, three days after injury, there was a 7-fold increase in ...
Negotiated Living: An Ethno-Historical Perspective of Punta Allen
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.
A Decomposition of the Group Algebra of a Hyperoctahedral Group
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.
Teaching Water Safety Skills to Children with Autism Using Behavioral Skills Training
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.
Ion Beam Synthesis of Binary and Ternary Transition Metal Silicide Thin Films
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 ...
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
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.
Modeling of Fracture Toughness of Magnesium Alloy WE43 Before and After Friction Stir Processing
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.
Women Chief Housing Officers at State Universities in the Northwest United States
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.
Enhanced Coarse-Graining for Multiscale Modeling of Elastomers
One of the major goal of the researchers is to reduce energy loss including nanoscale to the structural level. For instance, around 65% of fuel energy is lost during the propulsion of the automobiles, where 11% of the loss happens at tires due to rolling friction. Out of that tire loss, 90 to 95% loss happens due to hysteresis of tire materials. This dissertation focuses on multiscale modeling techniques in order to facilitate the discovery new rubber materials. Enhanced coarse-grained models of elastomers (thermoplastic polyurethane elastomer and natural rubber) are constructed from full-atomic models with reasonable repeat units/beads associated with pressure-correction for non-bonded interactions of the beads using inverse Boltzmann method (IBM). Equivalent continuum modeling is performed with volumetric/isochoric loading to predict macroscopic mechanical properties using molecular mechanics (MM) and molecular dynamics (MD). Glass-transition and rate-dependent mechanical properties along with hysteresis loss under uniaxial deformation is predicted with varying composition of the material. A statistical non-Gaussian treatment of a rubber chain is performed and linked with molecular dynamics in order predict hyperelastic material constants without fitting with any experimental data.
The Role of Misfit Strain and Oxygen Content on Formation and Evolution of Omega Precipitate in Metastable Beta-titanium Alloys
β-Ti alloys are widely used in airframe and biomedical applications due to their high ductility, high hardenability, and low elastic modulus. The phase transformations in β-Ti alloys are rather complex due to formation of metastable phases during various thermo-mechanical treatments. One such critical metastable phase, the hexagonal omega (ω) phase, can form in β-Ti alloys under quenching from the high temperature β phase and/or isothermal aging at intermediate temperature. Despite a substantial amount of reported works on the ω phase, there are several critical issues related to the ω formation need to be resolved, e.g. role of alloying elements and oxygen content. Therefore, this dissertation has attempted to provide insights into ω transformation in low misfit (Ti-Mo) and high misfit (Ti-V) binary systems as well as multicomponent (Ti-Nb-Zr-Ta) alloys. The evolution of ω structure, morphology and composition from the early stage (β-solution+quenched) to later stages after prolonged aging are systematically investigated by coupling transmission electron microscopy (TEM), atom probe tomography (APT) and high-energy synchrotron X-ray diffraction techniques. The influence of aging temperature and duration on characteristic of ω phase in Ti-Mo, and Ti-V alloys is addressed in details. It is found that compositional changes during aging can alter the structure, size and morphology of ω precipitates. In low misfit alloys, the ellipsoidal morphology of ω phase was retained during isothermal aging, while in high misfit alloys it changed from ellipsoidal to cuboidal morphology after prolonged aging. Secondly, ω transformation in biomedical Ti-Nb-Zr-Ta alloy is probed in which the micro-hardness was sensitive to microstructural changes. Furthermore, the evolution of oxygen concentration in ω precipitates during various aging conditions in binary Ti-Mo and Ti-V alloys are reported. It has been accepted that interstitial elements such as oxygen can largely alter mechanical behavior and the microstructure of Ti-alloys. Recently, oxygen is intentionally added ...
Black Males' Treatment Experiences in Mental Health Court: A Phenomenological Analysis
Mental health courts (MHCs) are part of an umbrella of specialty courts in which court officials, law enforcement, and treatment providers work together to seek alternative solutions to failed traditional approaches to justice. Researchers investigating MHCs indicated that the courts may be helpful in reducing recidivism and introducing offenders with mental health disorders to treatment services. I used the qualitative method of phenomenology to understand the experiences of young adult Black male clients' perceptions of mental health treatment in MHCs. Twelve participants ranged in age from 21-40 years. The research team identified three themes -- (a) helpful treatment factors, (b) relational growth, (c) treatment barriers – and five subthemes: (a) internal growth, (b) relational growth, (c) behavioral growth, (d) factors of marginalization, and (e) interpersonal barriers. Meaning pertaining to findings and implications for research and practice are discussed.
Strategies for Developing Individual Education Programs for Public School Music Students with Attention Deficit Hyperactivity Disorder and Dyslexia
Strategies for Developing Individual Education Programs for Public School Music Students with Attention Deficit Hyperactivity Disorder and Dyslexia explores the need for curriculum modifications, accommodations, and remediation techniques for beginner band students with specific learning disorders (SLDs) under the umbrella of Individual Education Programs (IEPs) or 504 plans for attention-deficit/hyperactivity disorder (ADHD) and/or dyslexia. ADHD and dyslexia are the most common of the neurodevelopmental disorders, often affecting a student's ability to stay focused and attentive; remain quiet and well behaved; comprehend written, visual and/or oral instruction; organize thoughts and materials; exhibit good time management; execute fine and gross motor skills; retain and recall information; decode symbols; process information quickly and correctly; maintain healthy, interpersonal relationships; and overcome anxiety. In order to provide inclusive instruction, music educators should understand how to identify these (often comorbid) conditions and the musical challenges these students might encounter, including time/pulse, notation, rhythm, posture, fingerings, and sight-reading. A guide for instrumental directors and private instrumental teachers, "How to Accommodate or Modify Musical Instruction for a Student with ADHD and/or Dyslexia" is included in this dissertation to provide useful information, multisensory techniques, and suggestions to help students with these learning disabilities achieve better success in the music classroom.
Memory and Continuity Amidst Irreversible Decline in the Texas Big Empty
This thesis interrogates sense of place and place attachment in the Big Empty on the north central Texas plains. The region stretches from the Red River on the north to the Colorado River basin on the south and from the Cross Timbers on the east to the Caprock escarpment on the west. Since 1930, the Big Empty has seen sustained and severe population decline such that some counties there now register less than a quarter the population they did at their peaks during the interwar years. Through in-depth field interviews, I examine sense of place and place attachment amidst apparently irreversible decline. I also describe conditions of postindustrial rurality arising from rolling reconfigurations of economic and social relations, particularly changes in scale in farming and the diminished centrality of productivist agriculture in local economies and culture, and how these conditions become legible through the study of place.
Local Phase Manipulation for Multi-Beam Interference Lithography for the Fabrication of Two and Three Dimensional Photonic Crystal Templates
In this work, we study the use of a spatial light modulator (SLM) for local manipulation of phase in interfering laser beams to fabricate photonic crystal templates with embedded, engineered defects. A SLM displaying geometric phase patterns was used as a digitally programmable phase mask to fabricate 4-fold and 6-fold symmetric photonic crystal templates. Through pixel-by-pixel phase engineering, digital control of the phases of one or more of the interfering beams was demonstrated, thus allowing change in the interference pattern. The phases of the generated beams were programmed at specific locations, resulting in defect structures in the fabricated photonic lattices such as missing lattice line defects, and single-motif lattice defects in dual-motif lattice background. The diffraction efficiency from the phase pattern was used to locally modify the filling fraction in holographically fabricated structures, resulting in defects with a different fill fraction than the bulk lattice. Through two steps of phase engineering, a spatially variant lattice defect with a 90° bend in a periodic bulk lattice was fabricated. Finally, by reducing the relative phase shift of the defect line and utilizing the different diffraction efficiency between the defect line and the background phase pattern, desired and functional defect lattices can be registered into the background lattice through direct imaging of the designed phase patterns.
Clocks and Mirrors
The essays featured in this collection highlight the gaps, as well as parallels, between mental illness and the human condition. In "Appearances," the narrator struggles with her own visual identity especially after reflecting on her Mom's own lengthy history with the mirror. In "Migrations," the lyrical voice of the narrator carries the reader through the typical day of a clinically depressed female character. Lastly, "Attempting the Fall," addresses the issues society has with mental illness by following the narrator from her suicide attempt to the mental ward.
Angular Analysis of a Wide-Band Energy Harvester based on Mutually Perpendicular Vibrating Piezoelectric Beams
The recent advancements in electronics and the advents of small scaled instruments has increased the attachment of life and functionality of devices to electrical power sources but at the same time granted the engineers and companies the ability to use smaller sources of power and batteries. Therefore, many scientists have tried to come up with new solutions for a power alternatives. Piezoelectric is a promising material which can readily produce continuous electric power from mechanical inputs. However, their power output is dependent upon several factors such as, system natural frequency, their position in the system, the direction of vibration and many other internal and external factors. In this research the working bandwidth of the system is increased through utilizing of two different piezoelectric beam in different directions. The dependency of output power with respect to rotation angle and also the frequency shift due to the rotation angle is studied.
The Duality of the Hitler Youth: Ideological Indoctrination and Premilitary Education
This thesis examines the National Socialists' ultimate designs for Germany's youth, conveniently organized within the Hitlerjugend. Prevailing scholarship portrays the Hitler Youth as a place for ideological indoctrination and activities akin to the modern Boy Scouts. Furthermore, it often implies that the Hitler Youth was paramilitary but always lacks support for this claim. These claims are not incorrect, but in regard to the paramilitary nature of the organization, they do not delve nearly deeply enough. The National Socialists ultimately desired to consolidate their control over the nation and to prepare the nation for a future war. Therefore, they needed to simultaneously indoctrinate German youth, securing the future existence of National Socialism but also ensuring that German youth carry out their orders and defend Germany, and train the youth in premilitary skills, deliberately attempting to increase the quality of the Wehrmacht and furnish it with a massive, trained reserve in case of war. This paper relies on published training manuals, translated propaganda, memoirs of former Hitler Youth members and secondary literature to examine the form and extent of the ideological indoctrination and premilitary training--which included the general Hitler Youth, special Hitler Youth subdivisions, military preparedness camps akin to boot camp, and elaborate war games which tested the youths' military knowledge. This thesis clearly demonstrates that the National Socialists desired to train the youth in skills that assisted them later in the Wehrmacht and reveals the process implemented by the National Socialists to instill these abilities in Germany's impressionable youth.
Programmable Mechanical Metamaterials with Negative Poisson's Ratio and Negative Thermal Expansion
Programmable matter is a material whose properties can be programmed to achieve particular shapes or mechanical properties upon command. This is an essential technique that could one day lead to morphing aircraft and ground vehicles. Metamaterials are the rationally designed artificial materials whose properties are not observed in nature. Their properties are typically controlled by geometry rather than chemical compositions. Combining metamaterials with a programmable function will create a new area in the intelligent material design. The objective of this study is to design and demonstrate a tunable metamaterial and to investigate its thermo-mechanical behavior. An integrated approach to the metamaterial design was used with analytical modeling, numerical simulation, and experimental demonstration. The dynamic thermo-mechanical analysis was used to measure base materials' modulus and thermal expansion coefficient as a function of temperature. CPS, the unit cell of the metamaterial, is composed of circular holes and slits. By decomposing kinematic rotation of the arm and elastic deformation of a bi-material hinge, thermo-mechanical constitutive models of CPS were developed and it was extended to 3D polyhedral structures for securing isotropic properties. Finite element based numerical simulations of CPS and polyhedral models were conducted for comparison with the analytical model. 3D printing of multi-materials was used for sample fabrication followed by tests with uniaxial compressive mechanical tests and thermal tests at 50℃. From the analytical model of the metamaterial, the contour plots were obtained for the effective properties – Poisson's ratio, the effective coefficient of thermal expansion of the metamaterial as a function of geometry and materials. A controllable range of temperature and strain was identified associated with maximized thermal expansion mismatch and contact on the slit surface of CPS, respectively. This work will pave the road toward the design of programmable metamaterials with both mechanically- and thermally- tunable capability and provide unique ...
Two-Phase Spray Cooling with Water/2-Propanol Binary Mixtures for High Heat Flux Focal Source
Two-phase spray cooling has been an emerging thermal management technique offering high heat transfer coefficients and critical heat flux levels, near-uniform surface temperatures, and efficient coolant usage that enables to design of compact and lightweight systems. Due to these capabilities, spray cooling is a promising approach for high heat flux applications in computing, power electronics, and optics. Two-phase spray cooling inherently depends on saturation temperature-pressure relationships of the working fluid to take advantage of high heat transfer rates associated with liquid-vapor phase change. When a certain application requires strict temperature and/or pressure conditions, thermo-physical properties of the working fluid play a critical role in attaining proper efficiency, reliability, or packaging structure. However, some of the commonly used single-component working fluids have relatively poor properties and heat transfer performance. For example, water is the best coolant in terms of properties, yet in certain applications where the system operates at low temperature ambient, it cannot be implemented due to freezing risk. The common solution for this problem is to use the antifreeze mixtures (binary mixtures of water and alcohol) to reduce the freezing point. In such cases, utilizing binary mixtures to tune working fluid properties becomes an alternative approach. This study has two main objectives; (1) to experimentally investigate the two-phase spray cooling performance of water/2-propanol binary mixture, and (2) to numerically investigate the performance of an advanced heat spreader featuring high and directional thermal conductivity materials for high heat flux focal sources. The first part of the study involves experimental characterization of heat transfer performance. Tests are conducted on a small-scale, closed loop spray cooling system featuring a pressure atomized spray nozzle. The test section, made of copper, measures 10 mm x 10 mm x 2 mm with a plain, smooth surface. A cylindrical copper block, with a matching size square ...
African American Children in the Jim Crow North: Learning Race and Developing a Racial Identity
This thesis explores how African American children in the North learned race and racial identity during the Jim Crow era. Influences such as literature, media, parental instruction, interactions with others, and observations are examined.
Effect of Makerspace Professional Development Activities on Elementary and Middle School Educator Perceptions of Integrating Technologies with STEM (Science, Technology, Engineering, Mathematics)
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.
Chemical and Electronic Structure of Aromatic/Carborane Composite Films by PECVD for Neutron Detection
Boron carbide-aromatic composites, formed by plasma-enhanced co-deposition of carboranes and aromatic precursors, present enhanced electron-hole separation as neutron detector. This is achieved by aromatic coordination to the carborane icosahedra and results in improved neutron detection efficiency. Photoemission (XPS) and FTIR suggest that chemical bonding between B atoms in icosahedra and aromatic contents with preservation of π system during plasma process. XPS, UPS, density functional theory (DFT) calculations, and variable angle spectroscopic ellipsometery (VASE) demonstrate that for orthocarborane/pyridine and orthocarborane/aniline films, states near the valence band maximum are aromatic in character, while states near the conduction band minimum include those of either carborane or aromatic character. Thus, excitation across the band gap results in electrons and holes on carboranes and aromatics, respectively. Further such aromatic-carborane interaction dramatically shrinks the indirect band gap from 3 eV (PECVD orthocarborane) to ~ 1.6 eV (PECVD orthocarborane/pyridine) to ~1.0 eV (PECVD orthocarborane/aniline), with little variation in such properties with aromatic/orthocarborane stoichiometry. The narrowed band gap indicate the potential for greatly enhanced charge generation relative to PECVD orthocarborane films, as confirmed by zero-bias neutron voltaic studies. The results indicate that the enhanced electron-hole separation and band gap narrowing observed for aromatic/orthocarborane films relative to PECVD orthocarborane, has significant potential for a range of applications, including neutron detection, photovoltaics, and photocatalysis. Acknowledgements: This work was supported by the Defense Threat Reduction Agency (Grant No.HDTRA1-14-1-0041). James Hilfiker is also gratefully acknowledged for stimulating discussions.
Loyalty or Fairness: A Study of the Influence of Moral Foundations on Auditors' Propensity to Subordinate their Judgment
Subordination of judgment is a fundamental threat to auditor objectivity. Subordination of judgment occurs when auditors agree with their superiors either in spite of or without forming their own independent judgments. Many audit procedures rely on independent, critical thinking at every level of the audit team; however, a number of studies suggest that auditors tend to agree with superiors even when a superior's views clearly run contrary to generally accepted accounting principles. While there is general agreement among scholars that subordination of judgment is "bad," very little attention has been given to moral biases that might influence an auditor's tendency to subordination of judgment, or to potential remedies that could mitigate an auditor's tendency to subordinate judgment. Moral Foundations Theory suggests that individuals tend to make intuitive, normative evaluations of situations based upon a set of personal moral biases or preferences called "moral foundations." Two specific moral foundations could influence subordination of judgment in divergent ways. The moral foundation of loyalty-respect may make agreement with a superior's views seem more acceptable than would disagreement. Meanwhile, the moral foundation of fairness may make an auditor more sensitive to the observance of rules, resulting in less subordination of judgment when a superior's views run contrary to professional rules. Social Identity Theory suggests that in-group favoritism may exacerbate subordination of judgment in general; however, strengthening an auditor's professional identity salience (PIS) could strengthen an auditor's objectivity. PIS is the temporary, heightened awareness of an auditor's identity as a professional and their role as guardian of professional rules. As a result, PIS may interact with an auditor's innate sense of fairness, resulting in less subordination of judgment than when professional identity is less salient. Results supported the hypothesis that auditors tend to subordinate their judgment to that of a superior, but not that PIS ...
Determinants of Women's Autonomy in Nepal
Nepal in recent times has witnessed a proliferation of community-based organization (CBOs). Established by local residents, CBOs are small level organizations that promote and defend the rights and interests of people especially that of minorities and the disadvantaged. One such minority group that CBOs greatly focus on are women. Despite dramatic increase in the number of CBOs in Nepal its impact on women is understudied. The purpose of this dissertation is to analyze the relationship between Nepalese women's participation in CBOs and their autonomy. Autonomy comprises of four different dimensions; physical mobility, financial autonomy, household decision-making, and reproductive autonomy. Modifying the conceptual framework used by Mahmud, Shah, and Becker in 2012, I hypothesize that women who participate in CBOs experience greater autonomy. Data from the 2008 Chitwan Valley Family Study is used for analysis. Using SPSS, separate logistic regressions are run to analyze the relationship between CBO membership and the dimensions of autonomy. The results support three of the four proposed major hypotheses. Nepalese women who participate in CBOs have greater autonomy in terms of physical mobility, financial autonomy, and household decision-making. No evidence was found to establish link between CBO membership and reproductive autonomy. The variables that are controlled for in the study include age, caste, religion, education, marital status, exposure to television, exposure to radio, and relationship with one's mother-in-law.
What's in Your Garden? Assessing the "Eco-friendliness" of Plant Choices of Denton, Texas Gardeners
Urbanization is seen as a threat to biodiversity within urban ecosystems, which are largely reliant on humans for their composition. Two types of extremes exist in the spectrum of urban domestic gardens; on one end, the typical urban garden which is planted by landscapers at the time the house is built and is generally left unchanged, and, at the other, a "wild" landscape planted entirely with native plants which provides habitat for native fauna and pollinators. This study assesses the plant choices made by members of organized gardening groups-the Denton County Master Gardeners (DCMG), the Elm Fork Master Naturalists (EFMN), the Trinity Forks Native Plant Society (TFNPS), and Keep Denton Beautiful (KDB)-and toward which extreme these choices put these gardens on the psectrum. TFNPS and EFMN both fall closer to the wild garden extreme, with TFNPS the closest to a "wild garden." DCMG was almost directly between the two extremes, but fell closer to the typical urban garden. By looking at how these groups manage their gardens, we begin to understand the ways in which gardeners can mitigate and soften the harsh changes between wild landscapes and urban environments. Collaboration between groups could have the potential to encourage more people to use native plants which provide habitat for native fauna and pollinators if those in the typical urban garden spectrum could find in the "wild" gardens of those on the opposite end of the spectrum.
Cyclic Polarization of AA 3102 in Corrosive Electrolytes Containing Sodium Chloride and Ammonium Sulfate
Corrosion of all aluminum microchannel heat exchangers present a challenge in automotive and heating, ventilation, and air conditioning (HVAC) industries. Reproducibility of Salt Water Acetic Acid Test (SWAAT) has been questioned and a need to new corrosion tests with better reproducibility has risen. Cyclic polarization, that is an electrochemical test, was explored for its suitability for the assessment of AA 3102 tube material that is currently a popular aluminum alloy used in manufacturing of heat exchanger. Corrosive electrolytes containing 3.5 % sodium chloride with 0.5 % ammonium sulfate (high chloride) or 0.5 % sodium chloride with 3.5 % ammonium sulfate (high sulfate) at their pH or acidic (pH=4) were used to measure corrosion potential (Ecorr), protection potential (Epp), pitting potential (Epit), Tafel constants (βa and βc), corrosion rate (mpy). Corrosive electrolyte used in SWAAT test (4.2% Sea Salt at pH 2.9) was also used to compare corrosion resistance of AA 3102 in SWAAT electrolyte compared to the other electrolytes used in this research. Scanning electron microscopy (SEM) was used to observe and document sample surface corrosion damage after each electrochemical test on all samples. Results of the cyclic polarization tests indicated that SWAAT electrolytes was the most aggressive electrolyte resulting in highest corrosion rates compared to all other electrolytes used in this investigation. SEM results indicated AA 3102 alloy exhibited higher pitting tendency in electrolytes with high sodium chloride whereas high sulfate electrolytes cause appearance of uniform corrosion surface damage on this alloy. Both high sulfate and SWAAT electrolytes showed intergranular corrosion but high chloride electrolyte showed severe pitting of AA 3102. Mohammad Navid Dorreyatim- Cyclic Polarization of AA 3102 in Corrosive Electrolytes Containing Sodium Chloride and Ammonium Sulfate. Master of Science (Mechanical and Energy Engineering), December 2016, 98 pp., references, 31 titles.
Exploring Ahope Client Satisfaction and Attitudes
I led a participatory action research (PAR) project with the staff and homeless clients of Ahope Day Center in Asheville, North Carolina, which was meant to evaluate client satisfaction with services and attitudes about certain issues. Project is led by an inquiry group consisting of members of Ahope staff and Ahope clients. The project is a co-designed, co-implemented, and co-interpreted mixed-method evaluation of Ahope's services, client attitudes about education and the environment, client adaptive strategies, optimism levels, and a mapping of client daily routines. The data was collected through participant observation, document analysis, surveys, a listing activity, and informal interviews. Documents were coded using grounded theory and themes emerged related to the value of the intangibles of security, community, and ‘being seen' at Ahope while some suggestions were also made. Findings included client attitudes indicating the importance of the environment and education to clients, high optimism levels among clients, and a number of suggestions for the improvement of Ahope's services.