UNT Theses and Dissertations - 133 Matching Results

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Acute Endocrine Responses to Rest Redistribution with Heavier Loads in Resistance-Trained Men
The purpose of this study was to investigate endocrine responses to redistribution with heavier loads (RR+L) during back squat (BS) exercise in resistance-trained men. Ten men (mean±SE; 23±2 years, 175.6±2.0 cm, 78.0±3.4 kg, 4±1 training years) were assigned using randomization to either RR+L (4 sets of (2×5 repetitions) of BS with 30 s intra-set and 90 s inter-set rest using 75% of their 1RM) or traditional sets (TS; 4 sets of 10 repetitions of BS with 120 s inter-set rest using 70% of their 1RM). Fasted blood samples were collected pre-exercise (PRE), immediately post-exercise (IP), and 5 (+5), 15 (+15), and 30 (+30) minutes post-exercise to analyze the concentrations of testosterone (T), growth hormone (GH), cortisol (C), and blood lactate (BL). Two-way ANOVAs with repeated measures were used (p≤0.05). A main effect of condition (p=0.023) was observed for BL (RR+L; 5.9±0.5 vs TS; 6.7±0.4 mmol/L). A main effect of time point (p≤0.001) was observed for T, GH, C, and BL. T was greater at IP (8.8±1.1), +5 (9.0±1.1), +15 (8.5±1.0), and +30 (8.0±1.0) than PRE (7.1±0.8 ng/mL). GH was greater at IP (58.3±12.7), +5 (62.8±12.7), +15 (67.9±13.3), and +30 (52.8±11.2) than PRE (3.6±1.6 µIU/mL). C was greater at +15 (25.5±2.9) and +30 (25.6±2.7) than PRE (20.0±2.7 µg/dL). BL was greater at IP (8.6±0.6), +5 (8.2±0.6), +15 (7.4±0.5), and +30 (5.8±0.5) than PRE (1.4±0.2 mmol/L). RR+L resulted in lower BL but no differences in T, GH, and C responses compared to TS. Thus, practitioners may incorporate RR+L without affecting endocrine responses.
Adult Attachment, Perceived Social Support, and Problematic Video Gaming Behavior
With the growing popularity in video games, there has been increased concerns over the prolonged exposure to the entertainment medium. Problematic gaming is defined as a pattern of gaming behavior that causes significant impairment in personal, social, other important areas of functioning, often characterized by preoccupation and loss of interest in other areas. This study examined how problematic gaming behaviors may be influenced by insecure adult attachment and perceived social support from differing sources. It was hypothesized that avoidant attachment would have a significant direct and indirect effect (via perceived social support) on problematic gaming. In addition, perceived social support from online friends and from offline friends were hypothesized to moderate the relationship between attachment and problematic gaming, Participants were recruited from both SONA (n = 151) and Amazon's Mturk (n = 264) to complete an online research questionnaire that measured variables of interest. Results indicated that the direct and indirect effects of attachment avoidance on problematic gaming were supported in both subsamples but the moderator effects were not. Further exploratory analysis found that anxious attachment demonstrated a similar pattern as avoidant attachment, but with a significant moderator effect of perceived social support from online friends (enhance) on the attachment anxiety and problematic gaming relation. Additionally, anhedonia and depressive symptoms were found to be significantly correlated with problematic gaming. Limitations, future research directions, and clinical implications are discussed.
Alexandria Ocasio-Cortez: Media Coverage of Age, Gender, and Ethnicity in the 116th Congress
This study focuses on Alexandria Ocasio-Cortez, the U.S. Representative for New York's 14th Congressional District, and how news media portray her based on her gender, age, and ethnicity, which still play essential roles in the political system in the United States. The analysis of previous academic research, newspaper articles from the New York Times and the Washington Post (June 1, 2018 to June 30, 2019) and framing and feminist theories are used to evaluate coverage of Alexandria Ocasio-Cortez. The newspaper stories are examined based on the framing of traits including being the youngest woman ever elected to Congress, being Latina, and being one the most progressive politicians in the Congress. The main objective of this study is to shed light on a topic that at this moment in time is more relevant than ever because the 116th Congress has the highest number of women and women of color in U.S. history. I examine media coverage that Rep. Alexandria Ocasio-Cortez receives for stereotypical frames, so that, overall, all women running or holding public office may receive unbiased and more balanced media coverage. This study also intends to hold media outlets accountable for the way they portray different candidates because it has a significant influence on the voting population.
Analysis of Interrelationships between Climate Change and Cotton Yield in Texas High Plains
The Texas High Plains produces the most substantial amount of cotton in Texas. The region is a semi-arid area with limited precipitation, and it is, therefore, susceptible to climate change. Cotton production in the Texas High Plains is mostly dependent on irrigation to increase yield. The overall goal of this research was to study the interrelationships between climate change and cotton yield using correlation analysis and also to study how climate has changed in the region using trend analysis. A three-decade data (1987-2017) was analyzed to establish the relationship between climate change and cotton and also to determine how climate has changed in the area over the last 30 years. The research used precipitation and temperature data to assess climate change.The results of this research showed that annual mean temperature has lesser impacts on cotton yield, and the correlation between annual precipitation and cotton yield is insignificant. It also found out that high rates of temperature at the boll opening stage of cotton growth results in decreased cotton yield and that at the boll development and boll opening stages, precipitation is needed. Again, the research indicated that, on average, there had been a significant increase in temperature, but precipitation trends are insignificant. About 60% of cotton acreage in the area is irrigated. Therefore the research also found out that increasing trends of cotton yield may contribute to the decline of groundwater in the area.
Analysis of N-Acylethanolamines in the Oilseed Crop Camelina sativa
To better understand the nature and function of N-acylethanolamines (NAEs) in Camelina sativa, we used mass spectrometry analysis to identify and quantify NAE types in developing seeds, desiccated seeds and seedlings. Developing seeds showed a differential increase in individual NAE species and an overall increase in NAE content with seed development and maturation. The NAE composition in mature, desiccated seeds mostly reflected the total fatty acid composition in the seed tissues, except for a noted absence of 11-eicosenoic (20C monounsaturated) fatty acid in the NAE pool. During seed stratification and seedling growth, individual NAE species were depleted at similar rates. Simulated drought treatments during seedling development resulted in a significant rise in NAE levels for the major 18C NAE types compared with untreated seedlings. Arabidopsis and Camelina mutants with reported altered fatty acid profiles were analyzed for their NAE compositions; both Arabidopsis and Camelina had relatively similar changes between compositions of total seed fatty acids and NAEs. Furthermore, seeds were analyzed from transgenic Arabidopsis and Camelina with engineered, non-native, long-chain polyunsaturated fatty acids (18C, 20C and 22C), and the results showed the production of novel N-acylphosphatidylethanolamines (presumed precursors of NAEs) and NAEs with the same long acyl chains. These results demonstrate i) that NAE levels change dramatically with seed and seedling development in Camelina, ii) that NAE levels in Camelina seedlings can be elevated in response to environmental stress, and iii) that the pool of NAEs can be manipulated by making alterations to seed fatty acid compositions, some of which may have promise for the production of novel, bioactive NAEs.
Anxiety in the Workplace: A Study of Different Anxiety Relief Methods for Hotel Employees
There is a lack of anxiety relief methods used in the hospitality workplace. This study examines the effectiveness of two forms of anxiety relief through four different methods. The data collection took place in classroom environments at the University of North Texas and the University of New Orleans, both of which are located in southern USA. The independent variables are the recovery method, the mediator variables are restorativeness and emotional improvement, and the dependent variables are negative job affects, positive job affects, turnover intention, and job commitment. Professors were asked for some time during their lecture to conduct the experiment in a classroom environment during the students' class time. Eight classes were visited, with each class being exposed to a designated anxiety relief method. The anxiety relief methods consisted of using a virtual reality headset with sound, virtual reality headset without sound, nature pictures with sound, and nature pictures without sound. Results of 206 usable surveys indicated virtual reality recovery method evoked higher levels of restorativeness than picture recovery method. Restorativeness partially mediated the effects of positive job affects and job commitment. lastly, emotional improvement partially mediated the effects of negative job affects, positive job affects, and turnover intention.
Anxiety Sensitivity and Nonmedical Prescription Drug Use among Adolescents
Research suggests that non-medical prescription drug (NMPD) use is becoming increasingly prevalent, particularly among adolescents. A critical step towards developing effective intervention efforts requires identifying adolescents who are at risk for NMPD use. An extensive literature suggests that both adolescents and adults with elevated anxiety sensitivity (AS) are at greater risk for problematic substance use, and a small body of work has identified similar links with NMPD use specifically among adults. However, most of this literature combines all prescription drugs into a single category, and no work has evaluated the relation between AS and NMPD use among adolescents. The current study endeavors to further this area of research by examining the relation between AS (overall and subscales) and NMPD use among adolescents. The project evaluated 276 adolescents (age 9-19 years) enrolled in a residential treatment program on level of AS, including sub-dimensions (i.e., cognitive, physical, and social), and NMPD use across three categories of drugs: analgesic (e.g., Vicodin®), anxiolytic (e.g., Xanax®), and stimulant (e.g., Adderall®). A series of logistic regression models indicated that overall AS predicted nonmedical analgesic use, but not anxiolytic/sedative or stimulant use. A closer investigation of the AS subscales demonstrated that only the AS social subscale significantly predicted nonmedical analgesic and anxiolytic/sedative use. These results suggest that AS is related to NMPD use among adolescents, highlighting the need for future work to disaggregate the assessment of NMPD use into specific drug classes and explore the subscale dimensions of AS.
Assessing Agricultural and Hydrologic Potential of Ancestral Puebloan Community Centers using Open Source Data
The Pueblo III period marks a critical shift in settlement location of Ancestral Puebloan people within the Mesa Verde region. Community centers during the Pueblo I and Pueblo II periods were built on mesa tops, whereas canyon-rims and alcoves became the preferred settlement location during the Pueblo III period. Beginning in the Pueblo I period, community centers consisted of linear roomblock villages. By the late Pueblo II period great house community centers influenced by the Chaco culture system spanned the Mesa Verde region. The Pueblo III period hallmarks the transition to canyon-rim villages and cliff dwellings. The location of these Pueblo III centers is thought to be related to the need for a defensive position on the landscape, and access to water sources. This shift in settlement locations undoubtedly led to change in the access to resources, such as water, arable farmland, and wild food plants and game. This study aims to evaluate whether the change in community center location impacted the accessibility to arable farmland and water sources immediately available to Ancestral Puebloan people throughout time. Specifically, several variables related to farming potential and hydrologic potential, including soil type, soil moisture, elevation, cropland suitability, distance to water sources, drainage density, and hydrogeologic units were evaluated. Nine community centers within the McElmo drainage area in southwestern Colorado ranging in age from the Pueblo II to Pueblo III periods were included in this study.
Athletic Participation as a Protective Factor for Childhood Maltreatment
The purpose of the study was to examine whether athletic participation as a child and/or adolescent acts as a protective factor for youth who endure childhood maltreatment. After screening for childhood maltreatment, our 269 participants were separated into either an athlete group or a non-athlete group and compared using two one-way multivariate analyses of covariance (MANCOVA). Emotional neglect served as the covariate due to non-athletes' significantly higher emotional neglect scores than athletes. The first MANCOVA compared athletes and non-athletes on positive outcomes, which included measures of post-traumatic growth, three adaptive coping strategies, and self-compassion. In the second MANCOVA, we assessed for differences between athletes and non-athletes on negative outcomes, which included measures of traumatic, depressive, and anxious symptomology and a maladaptive coping strategy. Neither MANCOVA reached significance, rejecting our hypothesis that athletes would be more resilient than non-athletes to the negative impact of childhood maltreatment. Discussion considers possible reasons for the lack of significance, such as the recency of athletic participation or the specific type of maltreatment experienced, as well as limitations and directions for future research.
Australian Mateship and Imperialistic Encounters with the United States in the Vietnam War
This thesis attempts to prove the significance of the relationship between the United States and Australia, and how their similar cultures and experiences assisted creating that shared bond throughout the twentieth century. Chapter 2 examines the effects of the Cold War on both the United States and Australia, as well as their growing relationship during that period. There is some backtracking chronologically in order to make connections to important historical legacies such as the ANZAC Legend and settlement on the periphery of their respective societies. Then the first half of chapter 3 delves into the Vietnam War by examining the interactions of the American support unit, the 11th Combat Aviation Battalion, a helicopter unit that includes transports and gunships. Afterwards, the latter half of chapter 3 examines the Australians' after-action reports to better understand their tactical and operational methods. Finally, chapter 4 provides an overview of Australian and American interactions between the advisers and the Vietnamese, as well as their attitudes towards the end of the war and the withdrawal from Vietnam. The conclusion summarizes the significance of the thesis by reemphasizing the significance of US-Australian interactions in the twentieth century and the importance of continued studies on this topic between US and Australian historians.
The Austrian Army in the War of the Sixth Coalition: A Reassessment
The Austrian army played a crucial role in Napoleon's decisive defeat during the War of the Sixth Coalition. Often considered a staid, hidebound institution, the army showed considerable adaptation in a time that witnessed a revolution in the art of war. In particular, changes made after defeat in the War of the Fifth Coalition demonstrate the modernity of the army. It embraced the key features of the new revolutionary way of war, including mass mobilization, a strategy of annihilation, and tactics based on deep echelonment, mobility, and the flexible use of varied formations. While the Austrians did not achieve the compromise peace they desired in 1814, this represented a political failing rather than a military one. Nevertheless, the Austrian army was critical in securing the century of general European peace that lasted until the dawn of the Great War.
Ayurveda as Medicine
Complimentary and alternate medicine, especially Ayurveda is gaining popularity in United States. However, there are various barriers that people face in adopting Ayurvedic practices into their lives and making cultural, familial and societal changes to better their health. This research explores these relationships and barriers behind why some people adopt and are able/unable to sustain Ayurvedic practices in the presence of traditional bio-medicine.
BC Framework for CAV Edge Computing
Edge computing and CAV (Connected Autonomous Vehicle) fields can work as a team. With the short latency and high responsiveness of edge computing, it is a better fit than cloud computing in the CAV field. Moreover, containerized applications are getting rid of the annoying procedures for setting the required environment. So that deployment of applications on new machines is much more user-friendly than before. Therefore, this paper proposes a framework developed for the CAV edge computing scenario. This framework consists of various programs written in different languages. The framework uses Docker technology to containerize these applications so that the deployment could be simple and easy. This framework consists of two parts. One is for the vehicle on-board unit, which exposes data to the closest edge device and receives the output generated by the edge device. Another is for the edge device, which is responsible for collecting and processing big load of data and broadcasting output to vehicles. So the vehicle does not need to perform the heavyweight tasks that could drain up the limited power.
Black and White Attitudes toward Interracial Marriage in the U.S.: The Role of Social Contact Characteristics
This research advances the literature on interracial marriage by using variables that align with the social contact hypothesis. The purpose of this project is to accurately gauge the exact social predictors influencing current attitudes towards Black and White interracial marriage. Multiple regression models containing social contact predictors are analyzed using data from the 2018 General Social Survey. The conclusive review of the literature summarizes age, region, and education as essential social contact predictors of attitudes towards interracial marriage. Therefore, the formulated hypotheses and multiple regression models measure this specific relationship controlling for other predictors such as sex and income. For Whites, the two most significant factors are age and living in the south vs. the west. Interestingly, a college education is not significant. For Blacks, the key contact variable that seems to matter is age. Baby boomers are less likely to favor interracial marriage. Overall, results show areas of convergence. Therefore, one's age is significant predictor for White and Black acceptance. However, it also shows divergence-region appears to only matter for Whites. Accordingly, younger Blacks and Whites were more likely to favor close relatives marrying individuals of the opposite race. Older Blacks and Whites were less likely to support interracial marriage. This analysis displays some of the critical gaps in using the social contact hypothesis to measure beliefs in Black and White conformity. Thus, there is a need to develop more logical variables to help solidify the exact social forces effecting attitudes towards interracial relationships.
A 'Bohemian' Premiere? Smetana's "The Bartered Bride" and National Identity in 1909 New York
When Czech composer Bedřich Smetana's opera The Bartered Bride received its American premiere at the Metropolitan Opera in February 1909, New York music critics published positive reviews which displayed a great fascination with the many "Bohemian" aspects of the production. However, certain comments or language used by some critics indicate that American opinions of the Czech people were less than positive. After Czechs began immigrating to America en masse in 1848, already-established American citizens developed skewed cultural perceptions of the Czech people, established negative stereotypes, and propagated their opinions in various forms of press throughout the nation. Despite a general dislike of the Czechs, reviewers revered The Bartered Bride and praised its many authentic "Bohemian" qualities. This research explores the idea of a paradoxical cultural phenomenon in which the prejudice against Czech people did not fully cross over into the musical sphere. Instead, appreciation for Czech music and musicians may have trumped any such negative opinions and authentic Czech productions such as The Bartered Bride may have been considered a novelty in the eyes of early twentieth-century New Yorkers.
Bridging the Fantastical Gap: Dread and the Uncanny in the Score of "It Follows"
"It Follows" (2014), written and directed by David Robert Mitchell, premiered at the Cannes Film Festival in 2014. It chronicles the story of Jay, a college student who contracts a curse through sexual intercourse. The curse manifests itself as a human whom only the infected persons can see, always following at a walking pace, and determined to kill if it catches up. This thesis demonstrates the score's crucial role in establishing affect, setting, and character in a film with sparse dialogue and a silent monster. Moreover, the score creates a sense of the uncanny by complicating the binary between music and sound effect and fulfills the need to create dread without resorting to the loud or sudden sounds traditionally heard in horror films. The score's composer, Richard Vreeland, achieves this effect by drawing on both classical film scoring techniques as well as more modern horror scoring styles. It is this interaction between styles that enhances the viewers' experience of dread and horror in the film. This thesis analyzes how Vreeland's score for "It Follows" exploits the poetics of the fantastical gap, of the uncanny, and of musical semiosis. I primarily focus on the "Heels" theme and use of drones in "It Follows," tracing how these musical features blur the distinction between what is score and what is sound effect. I also examine the use of melodic themes in a primarily non-melodic score. By analyzing these elements, I show how Richard Vreeland uses both classical and modern scoring techniques to answer his own question: "Why is this scary? What could push that emotion even further?"
The Buffering Effects of Religiosity on Adolescent Alcohol Abuse Coping following Victimization
This research comprised a secondary study using the National Longitudinal Study of Adolescent Health restricted data set to examine the buffering effects of religiosity on adolescent alcohol coping following victimization within the context of Agnew's general stain theory. Its purpose was to determine if religiosity buffered the effects of alcohol abuse coping following victimization for native-born and foreign-born non-Hispanic adolescents, and was designed as a follow-up research study to similarly replicate a prior study limited to native-born and foreign-born Hispanic adolescents. This study's findings were consistent with prior research that higher religiosity was generally predictive of lower levels of alcohol abuse. However, in the presence of violent victimization, religiosity did not buffer later increased alcohol abuse coping for non-Hispanic adolescents. Native-born religiously oriented adolescents were as likely to abuse alcohol following violent victimization as their native-born non-religious peers. Foreign-born religiously oriented versus non-religiously-oriented adolescents did not have statistically significant different outcomes on later alcohol abuse following victimization. Foreign-born non-Hispanic adolescents as a group appeared generally insensitive to victimization strain as measured by alcohol abuse coping. An important outcome of this study was the collateral finding that being Catholic substantially increased the likelihood of later alcohol abuse for both native-born and foreign-born non-Hispanic adolescents; the increase in alcohol abuse for foreign-born adolescents was especially pronounced. The study's findings have particular relevance for adolescent counseling and others working with adolescents, and especially for those working within a religious context. Numerous areas for additional research are identified and discussed.
A Century of Ash
Contained within is a sample, consisting of the first twelve chapters, which portray the final days of the fictional Polian War. The events are a springboard for the rest of the novel, and indeed the series.
Clementi the Scientist: Contemporary Reception of His Symphonies
Muzio Clementi's symphonies were first performed in London between 1786 and 1796. After an extended hiatus from 1796 to 1813, his symphonic works appeared on programs again from 1813 to 1824. Clementi's career as a symphonist corresponds closely with trends in London's concert life. The reception of Clementi's symphonies during his lifetime has frequently been misinterpreted by scholars who oversimplify the use of "science" in musical discourse of the day and fail to consider the positive connotations of this adjective, so frequently applied to Clementi. Musical discourse at the time addressed the science and art of music emphasizing a composition, or its composer's, science, harmony, effects, genius, and the audience's response. Though an unstated ideal, reviews evince a preference for balancing scientific and artistic display. Reviews of Clementi's symphonies suggest he initially struggled to balance the technical and artistic qualities of his compositions but succeeded, according to reviews, in finally doing so in 1796. After his early efforts, Clementi was consistently praised as worthy to stand among the current and most prestigious composers of the continent: Haydn and Mozart initially, and Beethoven and Rossini later.
Collected Stories
A collection of short fiction stories that fixate on the role of the strange and the imagined.
A Combined Theoretical and Experimental Study on Deposition of Solid State Materials
Deposition of solid state materials span a wide variety of methods and often utilize high energy sources such as plasmas and ultra-violet light resulting in a wide variety of characteristics and applications. A fundamental understanding is essential for furthering the applications of these materials which include catalysis, molecular filtration, electronics, sensing devices, and energy storage among others. A combination of experimental and theoretical work is presented here on several materials including 2D silicates on Pd, boron oxide, and vanadium oxynitride. Silicate formation under low energy electron microscopy demonstrate film permeability to oxygen, while ab initio molecular dynamics simulations reveal the possible initial mechanisms associated with the formation of boron oxide films during atomic layer deposition. Lastly, vanadium oxynitrides have shown preferential sputtering of N over O sites and theoretical binding energies serve as a guide for assigning experimental x-ray photoelectron spectra.
A Comparative Analysis of Saudi and U.S. Online Newspapers' Framing of Saudi Women's Issues: Content Analysis of Newspaper Coverage Before and After Saudi Vision 2030
Previous research on framing has proved its strong effects on the social perception and political preferences of individuals. Therefore, the aim of this research is to explore how Saudi women's issues have been framed in a sample of United States and Saudi newspapers. Saudi Vision 2030 is the post-oil plan for the Kingdom of Saudi Arabia that was announced on April 25, 2016. The sample of this thesis was 300 news stories from eight newspapers. The U.S. newspapers were the New York Times, the Washington Post, the Wall Street Journal, and the Los Angeles Times. The Saudi newspapers were Al Riyadh, Okaz, Al Jazirah, and Al Watan. This thesis explores how these issues have been covered before and after Saudi Vision 2030 by answering five basic questions. Quantitative and qualitative methods were used to analyze the news stories. For the quantitative analysis, five pre-defined generic frames from Semetko and Valkenburg were adopted: conflict frame, human interest frame, morality frame, economic consequences frame, and responsibility frame. An inductive approach to find the new frames was used for the qualitative analysis. Moreover, this thesis looked at how U.S. and Saudi newspapers have visually framed Saudi women through an analysis of the types of images used in the news stories related to Saudi women's issues. The main finding suggests that within the used frames in the newspapers, the U.S. newspapers focused more on the human-interest frame, while the Saudi newspapers mostly used the economic frame. Furthermore, the types of issues covered are discussed.
Comparative Resistomics of Ancient and Modern Human Microbiomes
Increased exposure to antibiotics has led to the dissemination of genes conferring resistance to antimicrobial metabolites throughout human microbiomes globally via horizontal gene transfer (HGT). This has resulted in the emergence of new resistant strains leading to a rising epidemic of deaths from previously treatable infections. Evidence suggests that before the age of anthropogenic antibiotic use, microbes living within a community produced antibiotic metabolites and, subsequently, maintained such genes for several useful functions and a balance of diversity in nature. The question of the origin of these resistant genes is difficult to answer, but with continued advancements in ancient genomic analysis, researchers have developed methods of acquiring a more accurate representation of the microbiome associated with our human ancestors by extracting fossilized microbial specimens from dental calculus and directly sequencing the metagenomes. This thesis outlines the production of taxonomic and functional profiles of 20 different human and non-human oral microbiome samples using metagenomics tools originally developed for living individuals, altered for use with ancient microbial specimens. Putative antimicrobial resistant (AMR) genes derived from these profiles were reconstructed and conserved functional regions were identified. From the data that is available regarding the human microbiome from a range of time points throughout history dating back to Neanderthal specimens, it is possible to elucidate relationships between these AMR genes and to better understand the evolutionary trajectory of antibiotic resistance.
Comparing Diabetic and Non-Diabetic Latinxs: Racial Discrimination Perception, Depressive Symptoms, and Blood Pressure
Associations between greater perceived racial discrimination and both higher levels of depressive symptomology and higher blood pressure have been established in the literature. Research has found that depression is often comorbid with diabetes and individuals with type 2 diabetes are at an increased risk for depression as the prevalence of depression is 2 to 3 times higher in people with diabetes when compared to the general population. Additionally, individuals with type 2 diabetes are also at an increased risk for high blood pressure. Although these associations are present in the literature, no studies have been found that examine all of these variables in conjunction. The current study used data from the 2014 Health and Retirement Study to examine the associations among perceived racial/ethnic discrimination, depression symptoms, and blood pressure for older Latinx adults (ages 50+) with type 2 diabetes (n = 303) and without type 2 diabetes (n = 521), while controlling for sex, age, partner status, and education. Findings indicated diabetes status was positively associated with both depression symptoms (t(790) = 5.32, p < .001) and systolic blood pressure (t(703) = 2.74, p = .006). Racial/ethnic discrimination was positively associated with depression (r(206) = .14, p = .045); however, it was not associated with blood pressure. No statistically significant interactions were found. Discussion focuses on possible explanations for the research findings, future directions, and clinical implications.
Crafting Downtown Denton: An Exploration of Craft Beer Consumption as an Activity in Denton, Texas
Craft beer as a cultural phenomenon coincided with the revitalization of downtown Denton, Texas. Much of the existing literature on craft beer and its relation to place focuses on breweries rather than bars. This exploratory study aims to explain why people consume craft beer, what factors influenced its popularity in Denton despite little beer production, and to explore considerations for the promotion of Denton as a craft beer destination and making downtown an inclusive space. Data was collected through interviews, participant observation, and a survey. Findings indicated that craft beer consumption in Denton is largely related to perceptions of community, localism, and knowledge seeking. The ethos of the craft beer industry closely aligned with participants' perceptions of Denton as a city.
Crisis, New Imperialisms, and Accumulation by Dispossession: The Case of the Pakistan Railways
My research examines the three interrelated concepts of crisis; new imperialisms, spatial-temporal fix and accumulation by dispossession (ABD) stemming from the work of David Harvey as a way to understand the contested history of the Pakistan Railways. For the first thirty odd years after Pakistan's inception in 1947, the railways, a state-owned institution, was the primary mode of transport for the public, cargo, and workers. Alongside basic infrastructure, the railways had a vast network of hospitals, schools, workers' colonies and an array of physical infrastructure connected to production, operations and other aspects of the economy. The systematic ransack and decline of the Pakistan Railways reached its peak in 2010. Despite several attempts throughout the 1990s by successive democratic and military-led governments backed by the IMF/World Bank in 2015, it was announced that Pakistan railways would be revived under the banner of the 46 billion dollar China Pakistan Economic Corridor (CPEC) as part of the changing geopolitical context of growing regional connectivity and new Chinese imperialism. By examining the processes that underlie ABD, such as spatial-temporal fix, the following research shows that these processes not only reflect a shift of resources away from the public domain, but in Pakistan also entailed the transformation of the railways from a utilitarian welfare organization to an entity that facilitates looting, unbundling, and dispossession of shared resources and infrastructure.
Cultivating Liberation: The Effects of Collective Shaping on Context and Power Dynamics within Social Justice Narratives
Social issues are becoming increasingly apparent. More people are experiencing the impact of social issues directly and through their media consumption. It is important to understand and reflect on our collective impact on the media and how the media affects the collective. The purpose of the present study was to evaluate the effects of a collaborative workshop (collective shaping) and a verbal community that examined media depictions of social justice and injustice related to context and power dynamics. The effects of the workshop were evaluated using an A-B design with multiple probe measures across three participants. During the pre-, probe, and post-training assessments, participants watched videos and responded to a written prompt. Results of the study suggest that written responses were not adequately trained during the workshop. However, anecdotally, participant's verbal responding shifted drastically during the training workshop. The results are discussed within the context of the training apparatus, effects the workshop had on the participants and researchers, and progression forward.
Cultivating Liberation within a Verbal Community: Evaluating the Effects of Collective Shaping on Written Narratives and Reflective Statements about Social Issues
The purpose of this study was to evaluate the effects that a training workshop and collective shaping had on the reflective statements and feeling and emotion labels in a written response to videos relating to social issues. The workshop included a presentation interspersed with videos to help practice dialoguing and guide discussion toward generating discourse for social change. The effects of the workshop were evaluated using a single subject A – B design with multiple probe measures across three participants. Participants were given a prompt to write a descriptive narrative in response to a video clip, creating a permanent product for quantitative and qualitative analyses. The study resulted in slight increasing trends for both reflective statements and feeling and emotion labels for Participants 1 and 2. Further analyses show that Participant 3, despite showing little change across reflective statements and feeling and emotion labels, showed significant increase and more stability in the percentage of total words within reflective statements. The results of the workshop are discussed in the context of future research, including the role of social issues in our everyday language and how that affects us at a personal level.
Design Method for Cold-Formed Steel Shear Wall Sheathed with Polymer Composite Panel
In order to predict the strength of shear wall with cold-formed steel framing members, analytical models were reviewed. Multiple analytical models were studied, as well as twenty-one connection tests were performed. The connection tests consist of 50-ksi cold-formed steel framing track, different fastening configurations, and different sheathing thicknesses (1/8" and 1/2"). No.12 screw resulted in the highest peak load of all fastening configurations, while the rivet connection had the lowest peak load. In addition, failure modes were observed after conducting the connection tests including shear in fastening, screw pullout, and bearing in the sheathing. However, only the rivet and No.10 screw fastening configurations were used in the prediction analysis of the shear wall by the elastic model. Six shear wall tests were conducted on both panels (1/2"and 1/8" thickness). After doing the comparison between the experimental and the elastic model, the percentage difference for the 1/8" and the 1/2" polymer composite panels (3''along the edge and 6''along the chord stud), was very small. It was 6.2% for the 1/8" and 2.96% for the 1/2" panels. This means the analytical model can predict the shear wall peak load. However, the percentage difference was slightly higher being 7.4% for the 1/2" polymer composite panels with 6" along the perimeter with the 12" at the chord stud. After comparing the experimental values to the predicted value of shear walls, it was concluded that this model is the most appropriate analytical method for predicting the shear wall capacity framed with cold-formed steel sheathed with polymer composite panels. Many of these configurations were used in a prototype shelter that was constructed and built at the structural testing laboratory at the University of North Texas.
Design of a Wearable Flexible Resonant Body Temperature Sensor with Inkjet-Printing
A wearable body temperature sensor would allow for early detection of fever or infection, as well as frequent and accurate hassle-free recording. This thesis explores the design of a body-temperature-sensing device inkjet-printed on a flexible substrate. All structures were first modeled by first-principles, theoretical calculations, and then simulated in HFSS. A variety of planar square inductor geometries were studied before selecting an optimal design. The designs were fabricated using multiple techniques and compared to the simulation results. It was determined that inductance must be carefully measured and documented to ensure good functionality. The same is true for parallel-plate and interdigitated capacitors. While inductance remains relatively constant with temperature, the capacitance of the device with a temperature-sensitive dielectric layer will result in a shift in the resonant frequency as environmental or ambient temperature changes. This resonant frequency can be wirelessly detected, with no battery required for the sensing device, from which the temperature can be deduced. From this work, the optimized version of the design comprises of conductive silver in with a temperature-sensitive graphene oxide layer, intended for inkjet-printing on flexible polyimide substrates. Graphene oxide demonstrates a high dielectric permittivity with good sensing capabilities and high accuracy. This work pushes the state-of-the-art in applying these novel materials and techniques to enable flexible body temperature sensors for future biomedical applications.
Design of Ultra Wideband Low Noise Amplifier for Satellite Communications
This thesis offers the design and improvement of a 2 GHz to 20 GHz low noise amplifier (LNA) utilizing pHEMT technology. The pHEMT technology allows the LNA to generate a boosted signal at a lower noise figure (NF) while consuming less power and achieving smooth overall gain. The design achieves an overall gain (S21) of ≥ 10 dB with an NF ≤ 2 dB while consuming ≤ 30 mA of power while using commercial off-the-shelf (COTS) components.
"Despedida con Mariachi": The Musical Mediation of Masculine Grief in Mexican Immigrant Funerals
Music plays an important role in Mexican funeral ceremonies, acting as a vehicle for men to acceptably express emotions of bereavement. As an important symbol of mexicanidad (Mexicanness), mariachi music is often used in traditional Catholic funerals, ritualizing grief equally as a mourning of loss and a celebration of the life of a deceased person. Although a form of popular music, mariachi's secular songs go through a process of sacralization, becoming meaningful sites for experiencing grief. As a musical expression of Mexico's idealized gender norms mariachi opens an aesthetic sphere for masculine grief to be expressed, experienced, and socialized in an acceptable form. The purpose of this thesis is to investigate the musical mediation of masculine grief, experienced and ritualized within funeral ceremonies, and observed through an ethnographic study of Mexican immigrant communities.
Determining Event Outcomes from Social Media
An event is something that happens at a time and location. Events include major life events such as graduating college or getting married, and also simple day-to-day activities such as commuting to work or eating lunch. Most work on event extraction detects events and the entities involved in events. For example, cooking events will usually involve a cook, some utensils and appliances, and a final product. In this work, we target the task of determining whether events result in their expected outcomes. Specifically, we target cooking and baking events, and characterize event outcomes into two categories. First, we distinguish whether something edible resulted from the event. Second, if something edible resulted, we distinguish between perfect, partial and alternative outcomes. The main contributions of this thesis are a corpus of 4,000 tweets annotated with event outcome information and experimental results showing that the task can be automated. The corpus includes tweets that have only text as well as tweets that have text and an image.
Development and Disruption of Collateral Behavior and DRL Performances: A PORTL Exploration
One schedule of reinforcement that is used to decrease the rate of a target behavior is differential reinforcement of low rates (DRL). During this schedule, reinforcement is delivered for a target response if it occurs after a certain amount of time has passed since the last instance of this target response. The current study used a table-top game called PORTL and college student participants to investigate how collateral patterns develop and are disrupted during DRL schedules. After the participant developed a collateral pattern of behaviors with the objects, the researcher removed one of the objects that was part of the pattern and waited for a new pattern of behaviors to develop. Once the participant developed a new collateral pattern, the researcher removed a second object. This continued until there was only one object present. Results showed that the rate of reinforcement decreased following the removal of each object, then slowly increased as a new pattern developed.
Effect of Barrier Height on Magnitude and Character of Hurricane Harvey Washover Fans, Matagorda Peninsula, Texas
This study uses topographic profiles, washover fan volumes, and shoreline retreat rates to explore relationships between barrier types and Hurricane Harvey storm washover sedimentation. Pre- and post-Hurricane Harvey topographic profiles were created on 15 transects using Bare Earth LiDAR (2016) and surveyed elevations (2019). Depth and area of washover fan measurements were collected to estimate washover fan volumes. An inverse relationship was found between washover fan volume and pre- and post-storm barrier heights. Based on the topographic profiles, one section of shoreline had a scarp up to 3m high which blocked overwash, but appears to have increased shoreline erosion. In contrast, a low-lying section of shoreline generated relatively large washover fans, but experienced less shoreline retreat. Shoreline retreat was further quantified between 2014 and 2019 using Google Earth Imagery from 2014, 2016, 2017, and 2019 to track migration of the shoreline. The entire shoreline in the study area is undergoing relatively rapid retreat, but the results suggest that Hurricane Harvey increased erosional rates. The Colorado River Jetty borders the study area and may have acted as an anthropogenic barrier, likely reducing storm surge energy and contributing to marsh aggradation on transects in its close proximity. The study findings indicate that the identification and incorporation of other variables that influence washover magnitude would further the understanding of this complex natural system. The research results provide valuable information on the interaction of hurricane storm surge with natural and anthropogenic barriers, beach and dune erosion, and marsh aggradation along the coast of Texas.
The Effect of Welfare Benefit Levels on Female Headship in the AFDC and TANF Eras
The purpose of this study is to revisit the question of whether welfare benefit levels influence female headship, and whether the effect differs between the two main eras of welfare policy relevant to female headship, Aid to Families with Dependent Children (AFDC) and Temporary Assistance to Needy Families (TANF). This study adds to the existing literature by including more up to date data allowing for a comparison between the AFDC and TANF eras. Results show that the effect of welfare benefits on female headship rates changes from negative to positive after welfare reform occurred among blacks, while no change occured among whites.
Effectiveness of the SASSI-4 in Classifying Substance Use Disorders and Detecting Response Styles
The current study explored the effects of simulated adjustment domains (i.e., partial denial and social desirability) on specialized substance abuse measures in a sample of 104 inpatient offenders with substance use disorders. Results indicated nearly two thirds (57.9%) of offenders successfully escaped detection on the SASSI-4 and InDUC-2R. Further, subtle approaches employed by the SASSI-4 failed to detect unacknowledged substance use by simulators, and the remaining decision rules were redundant and most likely contributed to the false positive rates for non SU offenders. More promisingly, the current study developed an empirically based validity scale to bolster the SASSI-4's effectiveness in detecting response styles that showed initial promise. Results, a review of detection strategies for SU validity scales, and implications for assessment are further explored.
The Effects of Instructions on Schedule Sensitivity
There are many situations in which human performances appear insensitive to changing contingencies of reinforcement when compared to nonhuman operant performances. Explanations of these discrepancies have appealed to rule-governance and have provided some evidence that instructions produce these differences by restricting response alternatives as well as functioning as discriminative stimuli for other contingencies. In order to further evaluate these potential functions, a canonical study on rule-governance was systematically replicated. Five undergraduate participants were tasked with earning blocks by pressing a button during LED-signaled, fixed-ratio 7 and differential-reinforcement-of-low-rate 5-s schedules of reinforcement. Phase 1 of the experiment switched between these two schedules, with the schedule alternating every 1 minute. Phase 2 added instructions to "Go Fast" and "Go Slow" to the LEDs and programmed the lit LED to switch 30 seconds into each 1-minute session. Phase 3 removed the instructions from the LEDs and returned to the procedures of phase 1, with only one LED lit during each 1-minute session. Results showed that instructions influence the response rates as well as stimulus control over those rates. Results also showed that all participants ignored instructions conflicting with the reinforceable rate by the end of Phase 2. These findings indicate that instances of insensitivity may result from instructions restricting response alternatives and their stimulus control, as opposed to instructions signaling a second contingency. These findings are discussed in terms of the nature of instructional stimulus control, its relation to the operant unit of analysis, and alternative interpretations of other instances of insensitivity.
The Effects of Probiotics on Growth, and Metabolism in Juvenile Oreochromis mossambicus (Mozambique Tilapia)
Improving growth, lowering mortality rates, and having a faster turnaround to harvest is essential for the future of commercial aquaculture. The primary goal of this study was to determine if introducing a single strain probiotic Lactobacillus rhamnosus IMC 501 into the feed regimen of a commercially important aquaculture freshwater fish, Mozambique tilapia (Oreochromis mossambicus), would decrease mortality; change metabolic rates; and increase tissue wet mass (MW), standard length, growth rate and feed conversion rate (FCRs). IMC501 was added to the fishmeal in four increasing concentrations and compared to a control without probiotics. Results from two-way ANOVAs showed that both treatment levels and elapsed time had a significant effect on both mean standard length and wet mass; in the latter case, time points and treatments interacted with one another, showing that tilapia grew best with a moderate level of probiotics present. The growth benefits of probiotics continued for months after the initial treatments. Oxygen consumption (metabolic rate) was measured using closed respirometry and resulted in recording the first values for juvenile tilapia treated with probiotics. For oxygen consumption, there were significant treatment and time effects with significant interactions, indicating that metabolism increased with probiotics once the dosage exceeded three times the industry level. These results are consistent with the observed increases in mass, length and growth rates. These results demonstrate the importance of conducting dose-response experiments in order to determine the most effective concentration of probiotics in juvenile freshwater fish. Importantly, probiotics at the right concentration increase metabolic rates and can positively influence tilapia growth, which is of interest for the optimization of Mozambique tilapia production in aquaculture.
The Emergence of the Subconscious in Erik Satie's "Parade": The Search for Surrealism in Sound
This thesis investigates possible connections between the music of Erik Satie (1866-1925) and the later surrealist movement, turning to Parade (1917) in a case study that seeks to understand surrealism in music through the idea of self-exploration, a well-established interpretive approach in studies of surrealism in the visual arts. This thesis seeks to redefine surrealism in music not as a set of concrete musical characteristics, but as a collection of techniques meant to evoke subconscious turbulence by blurring the boundary between the "outside" and "inside," between conscious and subconscious, leading to a new discovery of higher or deeper truth. Satie's music aligns with the psychoanalytic elements of the discourse on surrealism. Psychoanalysis, pioneered by Sigmund Freud (1856-1939) and his followers in the 1890s in Vienna, permeated France around the time of the creation of the work. It inspired early surrealist techniques like automatism, illusory formal structures, collage, and stylistic allusion. This thesis demonstrates that such techniques can be discerned throughout Parade, not only in Satie's music, but also in its scenario, staging, costumes, and choreography. As such, Parade was a foundational work for the surrealist movement, with Satie's music contributing with the other media equally to the emotional and psychological impact of the ballet.
Encouraging Tolerance of and Cooperation with Dental/Medical Routines
The participant is a 61-year-old woman, diagnosed with a generalized anxiety disorder and profound intellectual disability who was referred to a behavior-disorders clinic, to increase cooperation with routine dental procedures. I used a behavioral treatment package consisting of stimulus fading, differential reinforcement, and extinction to establish tolerance of, and cooperation with, routine dental procedures. Results showed that cooperative responding varied throughout the progression of teaching the prerequisite steps (sitting in a chair, sitting in a variety of chairs, then working on sitting in the dental chair). However, by the end of the study, the participant engaged in the behavior of open mouth for 30 s and tolerated/cooperated with the experimenter using a plastic visual inspection tool for 30 s. Further research should evaluate the effectiveness of a similar treatment package to develop a more streamlined and systematic framework to improve compliance and tolerance.
Encrypted Collaborative Editing Software
Cloud-based collaborative editors enable real-time document processing via remote connections. Their common application is to allow Internet users to collaboratively work on their documents stored in the cloud, even if these users are physically a world apart. However, this convenience comes at a cost in terms of user privacy. Hence, the growth of popularity of cloud computing application stipulates the growth in importance of cloud security. A major concern with the cloud is who has access to user data. In order to address this issue, various third-party services offer encryption mechanisms for protection of the user data in the case of insider attacks or data leakage. However, these services often only encrypt data-at-rest, leaving the data which is being processed potentially vulnerable. The purpose of this study is to propose a prototype software system that encrypts collaboratively edited data in real-time, preserving the user experience similar to that of, e.g., Google Docs.
Equines Do Not Live for Grass Alone: Teaching Equines with Social Interaction
Most horse training methods heavily rely on negative reinforcement and punishment. However, there is a movement in the horse community to utilize positive reinforcement to meet training goals. Although food has been used effective as a reinforcer with horses, social interaction has also been demonstrated to function as a positive reinforcer for animals. Utilizing social interaction as a reinforcer may lead to several benefits for both the trainer and animal. Some of the benefits can be improved relationships between animals and their caretakers and improved animal welfare. The purpose of this study was to apply Owens and Owens et al. previous research protocols to three equines to assess if social interaction, in the form of petting and gentle scratching, would function as a reinforcer. Using a changing criterion design, this study demonstrated that petting and gentle scratching could function as a reinforcer to teach three equines to stay and come in their natural environment.
Ethnic Groups and Institutions: Can Autonomy and Party Bans Reduce Ethnic Conflict?
Can institutions successfully reduce ethnic conflict? Institutions such as autonomy and federalism are often advocated as a means to prevent ethnic conflict, however empirical evidence is largely mixed with regards to their effectiveness. In a similar manner, political parties have begun to receive more scholarly attention in determining their relationship with ethnic conflict, but their evidence is also mixed. In this research I examine autonomy, federalism, and the banning of political parties within ongoing ethnic group self-determination movements. While I do not find evidence for a relationship between autonomy and conflict, I do find that federalism increases the likelihood of ethnic conflict. Additionally, the banning of ethnic political parties indicates a strong increase the likelihood of ethnic conflict, while the banning of regional political parties significantly reduces the likelihood of ethnic conflict.
Evaluating Variables that Influence Research Staff Performance
Performance analysis, based on operant analysis of behavior, has been utilized since the 1960s to investigate behavioral skills or deficits in the workplace. One type of analytical tool is Carr et al.'s Performance Diagnostic Checklist- Human Services (PDC-HS). This functional assessment allows investigators to pinpoint causes of performance issues (e.g., a training issue, task clarification/prompting, insufficient resources/materials/processes, or performance consequences/effort/competition). Typically, the PDC-HS is used with clinicians and therapists. The purpose of this study is to extend Carr et al. by evaluating the PDC-HS in assessing the clinical performance of graduate-level research assistants working at a specialized clinic for the assessment and treatment of severe behavior disorders. For each participant, three supervisors, the study investigator and the participants themselves completed the PDC-HS with respect to the performance concern. Results of the PDCH-HS showed variability in congruence across the three groups of respondents. Due to the occurrence of the global coronavirus disease 2019 (COVID-19) pandemic during the study's investigation, the project was modified to assess different clinical performance involving safety procedures. The PDC-HS was re-administered to assess participants' cleanliness behavior and a subsequent targeted intervention was designed. Results showed no improvement of performance for 4/4 participants in the nontargeted intervention for clinic session performance and an increase for 1 participant in the targeted intervention for the cleanliness performance. Implications of PDC-HS results and limitations are discussed.
An Evaluation of a Waiting Period and DRL on Reducing Mands serving as Precursors to Self-Injurious Behavior
Extensive research has been conducted demonstrating the utility of differential reinforcement as an effective intervention for self-injurious behavior. However, the majority of this literature requires teaching an alternative response to access reinforcement. Further evaluation of treating self-injurious behavior in individuals that already possess the repertories to contact reinforcement appropriately. Prior to initiating the study, functional assessments were completed for both participant that demonstrated high-rate bursts of mands served as a reliable precursor to self-injurious behavior. In the present study, we evaluated a waiting period and differential reinforcement of low rate behavior on reducing mands while keeping self-injurious behavior at or near zero levels. Results indicated that shorter waiting periods and DRL values were effective at reducing mands and maintaining near zero levels of self-injurious behavior.
An Evaluation of Effectiveness and Efficiency of Matrix Training Permutations
Recombinative generalization is a generative outcome that involves responding to novel stimulus combinations, and it can be facilitated through an instructional approach called matrix training. A learner's history with constituent stimuli and the arrangement of combination stimuli within the instructional matrix may affect the likelihood of recombinative generalization. To investigate this further, the current project assessed recombinative generalization with novel combinations of abstract stimuli by programming specific training histories for undergraduate student participants. The matrix training conditions were: (a) trained constituents with overlap training, (b) untrained constituents with overlap training, (c) trained constituents with nonoverlap training, and (d) untrained constituents with nonoverlap training. We evaluated whether and the extent to which recombinative generalization occurred in each matrix training condition in comparison to a condition that included training the constituents and providing a word-order rule. Finally, we compared the training trials in experimental conditions to directly training all constituents and combinations. The results suggested both overlap conditions and the trained constituents with nonoverlap condition produced recombinative generalization, and the trained constituents with nonoverlap condition was the most efficient. These results could inform the training order and stimulus arrangements practitioners employ to program for recombinative generalization.
An Evaluation of Effects of Collective Shaping on Perspective Taking and Social Empathy Statements Related to Social Justice
Prejudice establishes coercive contingencies that restrict human rights and diminish quality of life. Social media has made the oppression experienced by individuals more apparent. Perspective taking and empathy can change prejudicial behavior by fostering relationships and encouraging self-identification with those who are different from ourselves. The purpose of the present study was to evaluate the effects of a guided collective shaping program on the occurrence of perspective taking and empathetic responses when viewing social justice media. The effects of the workshop were evaluated using a multiple baseline design across workshop topics. Written responses to video clips were analyzed before, during, and after training. The results of the study were inconclusive. The results of the training, based on the responses measured, indicate an increase in one measure of perspective taking and no changes in the other measures. At the same time, anecdotal observations indicated a change in the way participants talked about the issues over the course of the training. The results are discussed within the context of response form measurement, the COVID-19 pandemic, and potential research directions.
Examining Alcohol Related Consequences in Undergraduate Sorority Women
Members of Greek Life organizations consume more alcohol and participate in risky drinking behaviors at higher rate than their non-Greek counterparts due to deep rooted social norms within this population. Undergraduate sorority women at college and universities are often overlooked in research regarding trends in alcohol use in Greek Life organizations. However, women between the ages of 18 and 24 are more vulnerable to the consequences of heavy alcohol use compared to men, including liver disease, sexual assault, poor academic outcomes and post-collegiate alcohol use disorders (AUDs). Although higher education institutions are tasked with educating their students about safe alcohol use and protecting students from harm, these interventions are often inadequate in decreasing alcohol related consequences. Among students, sorority women consistently consume higher amounts of alcohol and exhibit higher rates of risky drinking behavior. This thesis aims to examine the unique alcohol-related consequences and risk factors sorority women face. Implications are discussed to guide college administrators, counselors and other supports that are likely to encounter issues associated with alcohol use within this population.
Experimental Investigation on Efficiency of Fresnel Lenses with Different Manufacturing Methods
Non-imaging Fresnel lenses have been playing an important role in improving the efficiency of the solar energy systems. Many researchers and scientists have devoted their research to optimize the design of the Fresnel lenses. Before it can contribute to energy efficiency increase, a Fresnel lens with optimized design will first need to be fabricated with the most cost-effective method as well as the best quality fabrication as possible. If targeted in a commercial market, feasibility of mass production with a minimum fabrication time would also be a consideration. To bring the design optimization of a Fresnel lens from a conceptual theory to a real-life increase in energy efficiency, the lens needs to be fabricated, tested, compared, and analyzed. This research thesis is intended to explore the performance of the lenses with optimized design through experimental investigations. The design optimization was achieved by a previous PhD student at UNT. A total of six lenses fabricated with four different methods along with two purchased lenses were tested with two different approaches. Multiple testing routes were conducted within a 10-month period to observe the effects of material decomposition and degradation on the lens performance. The resulting experimental data has provided a solid base for analyzing the performance of the lenses, in particular, the energy conversion efficiency increase of the solar cell by using each lens. The potential cause of the performance variation can be extracted from the comparison and evaluation.
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