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Examining the Shade/flood Tolerance Tradeoff Hypothesis in Bottomland Herbs Through Field Study and Experimentation

Description: While there is growing evidence that shade/flood tolerance tradeoffs may be important in distributions of bottomland hardwood trees and indications that they should apply to herbs, no studies have definitively explored this possibility. Four years of field data following historic flooding were supplemented with a greenhouse experiment designed to identify interactions congruent with tradeoffs. Fifteen bottomland species were grown in two levels of water availability and three levels of shade over 10 weeks. Results indicate responses of Fimbristylis vahlii and Ammannia robusta are consistent with tradeoffs. Modification of classical allometric responses to shade by substrate saturation indicates a potential mechanism for the tradeoff in A. robusta. Responses indicating potential for increased susceptibility to physical flooding disturbance are also discussed.
Date: May 2012
Creator: Sloop, Jordan
Partner: UNT Libraries

“Almost Astronauts”: Short Stories

Description: In this collection of short stories, I abduct experiences from my own life and take them on an imaginative journey. I experiment with elements of structure and point of view, often incorporating the magical or surreal to amplify the narrator’s internal landscape. As demonstrated in the title story, “Almost Astronauts,” these stories all deal with a sudden and sometimes destructive shift in the narrator’s perspective.
Date: May 2012
Creator: Miller, Laura I.
Partner: UNT Libraries

Impact of Congruence Between Self-disclosed Personal Information and Review on Source Credibility in Online Travel Reviews

Description: This experimental study examined the source-message congruence effect on source credibility by manipulating the congruence of the reviewer’s profile information (travel interest, geographical location) with no changes in the review content. the congruence effect was found to influence perceptions of the reviewer’s expertise in a travel interest. This finding suggests that revealing the reviewer’s travel interest can assist the credibility assessment of travel reviewers-particularly in terms of expertise-within the category of a travel interest. the refined classification of travel reviewers based on their travel interests can improve their usefulness as information sources for prospective travelers’ information searches. These attributes can further be employed as search cues if embedded in the reviewer’s profile.
Date: May 2012
Creator: Park, Hee Lye
Partner: UNT Libraries

Jiggs

Description: Jiggs is a documentary that explores how Jiggs Gaffney serves despite his mental disability. By observing Jiggs’ involvement at Pine Cove Christian Camps, and revealing his past, the documentary shows how anyone can be used for a greater good, and reveals how God can be served and glorified by anyone, no matter the individual circumstances.
Date: May 2012
Creator: Sosa, Mario
Partner: UNT Libraries

Investigating Realistic Scenarios of Biodiversity Loss on Ecosystem Functioning: Extirpation of Rare Species and Food Web Collapse in Tropical Floodplain Lagoons

Description: This thesis investigates the influence of nonrandom species loss on the structure and functioning of trophic floodplain lagoons. Two experiments were conducted based on different realistic scenarios of biodiversity loss using multitrophic fish assemblages derived from long-term survey data. Loss of fish diversity influenced overall ecosystem multifunctionality of these lagoons through complex multitrophic interactions throughout the aquatic food web. These results indicate that biodiversity loss from diverse multitrophic ecosystems can influence ecosystem structure and function and likely deviate from simplified food chain dynamics or patterns that emerged from single trophic level studies.
Date: May 2012
Creator: Pendleton, Richard McCall
Partner: UNT Libraries

Implementing a Physical Activity Centered Education Program for Individuals with Brain Injury

Description: Research has shown that health promotion programs (HPP) that incorporate education about physical activity (PA) are one mode of rehabilitation that can improve the health of individuals with disabilities. However, education-based PA curriculum is not included in the rehabilitation program for individuals with a brain injury, indicating a gap in services provided. Consequently, the purpose of this study was to create and deliver a physical activity centered education (PACE) program that supplemented the existing rehabilitation program for brain injury. PACE consists of an 8-week (16 session) program aimed to (1) increase self-efficacy for being physically active of PACE program participants, (2) increase PA stage of change in PACE program participants or the maintenance of adequate level of PA, and (3) improve the rehabilitation outcomes (i.e., abilities, participation, adjustment) of PACE program participants. Based on previous research, it is hypothesized that participation in PACE will result in (1A) increased self-efficacy for PA, (1B) greater self-efficacy for PA than the standard of care group, (2A) increased readiness to be physically active, (2B) greater readiness to change their PA behavior than the standard of care group, (3A) improved rehabilitation outcomes, and (3B) greater rehabilitation outcomes than the standard of care group. the PACE program resulted in: (1) an average increase of 19.36% in participants’ PA self-efficacy (effect size [ES] = 0.37), (2) 15 of the 22 PACE participants (68.18%) reported readiness to engage in regular PA , and (3) an increase in rehabilitation outcomes (i.e., abilities, adjustment, and participation)In conclusion, the PACE program can improve PA self-efficacy, readiness for regular PA behavior, and improved short-term rehabilitation outcomes.
Date: May 2012
Creator: Woolsey, Anne-Lorraine T.
Partner: UNT Libraries

Detection of Mercury Among Avian Trophic Levels at Caddo Lake and Lake Lewisville, TX

Description: Mercury (Hg) is a globally distributed toxicant that has been shown to have negative effects on birds. in the United States, avian taxa have been shown to possess high Hg concentrations in the northeast, Great Lakes and Everglades ecosystems; however, few studies have measured avian Hg concentrations in other geographic regions. Previous studies have documented high Hg concentrations in multiple organisms in east Texas, but birds were not included in these studies. the main objective of the present study was to quantify Hg concentrations in birds in differing trophic levels at Caddo Lake and Lake Lewisville, TX. Results suggest that Hg concentrations may be high enough to negatively impact some bird taxa, particularly those at high trophic levels, residing at both Caddo Lake and Lake Lewisville.
Date: May 2012
Creator: Schulwitz, Sarah Elizabeth
Partner: UNT Libraries

Experimental Determination of L, Ostwald Solubility Solute Descriptor for Illegal Drugs By Gas Chromatography and Analysis By the Abraham Model

Description: The experiment successfully established the mathematical correlations between the logarithm of retention time of illegal drugs with GC system and the solute descriptor L from the Abraham model. the experiment used the method of Gas Chromatography to analyze the samples of illegal drugs and obtain the retention time of each one. Using the Abraham model to calculate and analyze the sorption coefficient of illegal drugs is an effective way to estimate the drugs. Comparison of the experimental data and calculated data shows that the Abraham linear free energy relationship (LFER) model predicts retention behavior reasonably well for most compounds. It can calculate the solute descriptors of illegal drugs from the retention time of GC system. However, the illegal drugs chosen for this experiment were not all ideal for GC analysis. HPLC is the optimal instrument and will be used for future work. HPLC analysis of the illegal drug compounds will allow for the determination of all the solute descriptors allowing one to predict the illegal drugs behavior in various Abraham biological and medical equations. the results can be applied to predict the properties in biological and medical research which the data is difficult to measure. the Abraham model will predict more accurate results by increasing the samples with effective functional groups.
Date: May 2012
Creator: Wang, Zhouxing
Partner: UNT Libraries

Electrochemical Depostion of Bismuth on Ruthenium and Ruthenium Oxide Surfaces

Description: Cyclic voltammetry experiments were performed to compare the electrodeposition characteristics of bismuth on ruthenium. Two types of electrodes were used for comparison: a Ru shot electrode (polycrystalline) and a thin film of radio-frequency sputtered Ru on a Ti/Si(100) support. Experiments were performed in 1mM Bi(NO3)3/0.5M H2SO4 with switching potentials between -0.25 and 0.55V (vs. KCl sat. Ag/AgCl) and a 20mV/s scan rate. Grazing incidence x-ray diffraction (GIXRD) determined the freshly prepared thin film electrode was hexagonally close-packed. After thermally oxidizing at 600°C for 20 minutes, the thin film adopts the tetragonal structure consistent with RuO2. a hydrated oxide film (RuOx?(H2O)y) was made by holding 1.3V on the surface of the film in H2SO4 for 60 seconds and was determined to be amorphous. Underpotential deposition of Bi was observed on the metallic surfaces and the electrochemically oxidized surface; it was not observed on the thermal oxide.
Date: May 2012
Creator: Taylor, Daniel M.
Partner: UNT Libraries

My Land, My Life

Description: My Land, My Life is a documentary film about the woman, Jo Angela Lamb, who lives and works on Frying Pan Ranch in Texas Panhandle. the film explores the complexity of a ranch woman's experience that breaks the spell of the stereotyped image of American cowgirls. It also reflects on women ranchers’ relationship with their family members and their relationship with the land.
Date: May 2012
Creator: Zhang, Mingyun
Partner: UNT Libraries

Social Networking: the Benefits of Twitter for Music Fans and Consumers

Description: Due to the evolution of new media technologies, social networking websites have become major avenues for online media consumption. Twitter is one of many proven beneficial for online users. It is utilized for many different reasons, one of which includes music. It is then necessary to know how beneficial Twitter is for music fans and consumers. This study attempts to analyze the benefits of Twitter for music fans and consumers. Using an online survey, different gratification items are measured. Results reveal that some music fans and consumers do use Twitter for music purposes and that there is a statistically significant difference in terms of gratifications between those who use Twitter for music purposes and those who do not.
Date: May 2012
Creator: Perrilliat, Jessica A.
Partner: UNT Libraries

Alternative Complementation in Partially Schematic Constructions: a Quantitative Corpus-based Examination of COME to V2 and GET to V2

Description: This paper examines two English polyverbal constructions, COME to V2 and GET to V2, as exemplified in Examples 1 and 2, respectively. (1) the senator came to know thousands of his constituents (2) Little Johnny got to eat ice cream after every little league game. Previous studies considered these types of constructions (though come and get as used here have not been sufficiently studied) as belonging to a special class of complement constructions, in which the infinitive is regarded as instantiating a separate, subordinate predication from that of the “matrix” or leftward finite verb. These constructions, however, exhibit systematic deviation from the various criteria proposed in previous research. This study uses the American National Corpus to investigate the statistical propensities of the target phenomena via lexico-syntactic (collostructional analysis) and morpho-syntactic (binary logistic regression) features, as captured through the lens of construction grammar.
Date: May 2012
Creator: Lester, Nicholas A.
Partner: UNT Libraries

Baseband Noise Suppression in Ofdm Using Kalman Filter

Description: As the technology is advances the reduced size of hardware gives rise to an additive 1/f baseband noise. This additive 1/f noise is a system noise generated due to miniaturization of hardware and affects the lower frequencies. Though 1/f noise does not show much effect in wide band channels because of its nature to affect only certain frequencies, 1/f noise becomes a prominent in OFDM communication systems where narrow band channels are used. in this thesis, I study the effects of 1/f noise on the OFDM systems and implement algorithms for estimation and suppression of the noise using Kalman filter. Suppression of the noise is achieved by subtracting the estimated noise from the received noise. I show that the performance of the system is considerably improved by applying the 1/f noise suppression.
Date: May 2012
Creator: Rodda, Lasya
Partner: UNT Libraries

The Geography of Maternal Mortality in Nigeria

Description: Maternal mortality is the leading cause of death among women in Nigeria, especially women aged between 15 and 19 years. This research examines the geography of maternal mortality in Nigeria and the role of cultural and religious practices, socio-economic inequalities, urbanization, access to pre and postnatal care in explaining the spatial pattern. State-level data on maternal mortality rates and predictor variables are presented. Access to healthcare, place of residence and religion explains over 74 percent of the spatial pattern of maternal mortality in Nigeria, especially in the predominantly Muslim region of northern Nigeria where poverty, early marriage and childbirth are at its highest, making them a more vulnerable population. Targeting vulnerable populations in policy-making procedures may be an important strategy for reducing maternal mortality, which would also be more successful if other socio-economic issues such as poverty, religious and health care issues are promptly addressed as well.
Date: May 2012
Creator: Ebeniro, Jane
Partner: UNT Libraries

Relative Effectiveness of Anti-poverty Nonprofit Organizations in Assisting a Below Poverty Population in Dallas County and Tarrant County: Recipients of Faith-based and Non Faith-based Organizations

Description: Recent orders from the executive branch of the United States’ government have encouraged participation from faith-based organizations in providing human services because they are more effective in aiding impoverished citizens. This study examined the effectiveness of faith-based and non faith-based anti-poverty nonprofit organizations to find if one organization type is more effective in providing social services. the data for this study were collected through a survey-questionnaire which was administered to a convenience sample of 82 participants seeking assistance from four different nonprofit organizations (two faith-based and two non faith-based) in Dallas County and Tarrant County. the results from this study indicated that when controlling for demographic and socio-economic variables, recipients from faith-based organizations were less likely to report that they at least received services desired as compared to those who visited a non faith-based organization. Therefore, non faith-based organizations were better at meeting the needs of respondents than faith-based organizations.
Date: May 2012
Creator: Gregory, Callie
Partner: UNT Libraries

From Associates to Antagonists: the United States, Great Britain, the First World War, and the Origins of War Plan Red, 1914-1919

Description: American military plans for a war with the British Empire, first discussed in 1919, have received varied treatment since their declassification. the most common theme among historians in their appraisals of WAR PLAN RED is that of an oddity. Lack of a detailed study of Anglo-American relations in the immediate post-First World War years makes a right understanding of the difficult relationship between the United States and Britain after the War problematic. As a result of divergent aims and policies, the United States and Great Britain did not find the diplomatic and social unity so many on both sides of the Atlantic aspired to during and immediately after the First World War. Instead, United States’ civil and military organizations came to see the British Empire as a fierce and potentially dangerous rival, worthy of suspicion, and planned accordingly. Less than a year after the end of the War, internal debates and notes discussed and circulated between the most influential members of the United States Government, coalesced around a premise that became the rationale for WAR PLAN RED. Ample evidence reveals that contrary to the common narrative of “Anglo-American” and “Atlanticist” historians of the past century, the First World War did not forge a new union of spirit between the English-speaking nations. the experiences of the War, instead, engendered American antipathy for the British Empire. Economic and military advisers feared that the British might use their naval power to check American expansion, as they believed it did during the then recent conflict. the first full year of peace witnessed the beginnings of what became WAR PLAN RED. the foundational elements of America’s war plan against the British Empire emerged in reaction to the events of the day. Planners saw Britain as a potentially hostile nation, which might regard the United States’ ...
Date: May 2012
Creator: Gleason, Mark C.
Partner: UNT Libraries

A Global Stochastic Modeling Framework to Simulate and Visualize Epidemics

Description: Epidemics have caused major human and monetary losses through the course of human civilization. It is very important that epidemiologists and public health personnel are prepared to handle an impending infectious disease outbreak. the ever-changing demographics, evolving infrastructural resources of geographic regions, emerging and re-emerging diseases, compel the use of simulation to predict disease dynamics. By the means of simulation, public health personnel and epidemiologists can predict the disease dynamics, population groups at risk and their geographic locations beforehand, so that they are prepared to respond in case of an epidemic outbreak. As a consequence of the large numbers of individuals and inter-personal interactions involved in simulating infectious disease spread in a region such as a county, sizeable amounts of data may be produced that have to be analyzed. Methods to visualize this data would be effective in facilitating people from diverse disciplines understand and analyze the simulation. This thesis proposes a framework to simulate and visualize the spread of an infectious disease in a population of a region such as a county. As real-world populations have a non-homogeneous demographic and spatial distribution, this framework models the spread of an infectious disease based on population of and geographic distance between census blocks; social behavioral parameters for demographic groups. the population is stratified into demographic groups in individual census blocks using census data. Infection spread is modeled by means of local and global contacts generated between groups of population in census blocks. the strength and likelihood of the contacts are based on population, geographic distance and social behavioral parameters of the groups involved. the disease dynamics are represented on a geographic map of the region using a heat map representation, where the intensity of infection is mapped to a color scale. This framework provides a tool for public health personnel and ...
Date: May 2012
Creator: Indrakanti, Saratchandra
Partner: UNT Libraries

Alterations in Fatty Acid Amide Hydrolase (Faah) Transcript Levels and Activity Lead to Changes in the Abiotic Stress Susceptibility of Arabidopsis Thaliana

Description: N-Acylethanolamines (NAEs) are a class of bioactive lipids, and FAAH is one of the enzymes responsible for degrading NAEs in both plants and animals. in plants, FAAH appears to be closely associated with ABA, a phytohormone which has long been associated with plant stress responses, since the overexpression of FAAH in Arabidopsis results in ABA hypersensitivity. Therefore, it is reasonable to speculate that alterations in FAAH transcript levels will result in altered stress responses in plants. to investigate this hypothesis experiments were carried out in which wild type (WT), FAAH-overexpressing (OE), and T-DNA insertional FAAH knockouts of Arabidopsis (faah) were grown in MS media under stress conditions. the stress conditions tested included chilling stress, heavy metal stress induced by cadmium or copper, nutrient limitations induced by low phosphorus or low nitrogen, salt stress induced with NaCl, and osmotic stress induced with mannitol. the OE plants were consistently hypersensitive to all stress conditions in relation to wild type plants. Inactive FAAH overexpressors did not have the hypersensitivity to the salt and osmotic stress of the active OE plants and were instead tolerant to these stresses. FAAH2 (faah2) knockouts and FAAH 1 and 2 double knockouts (faah 1+2) were based on some root development parameters somewhat more tolerant than WT plants, but more sensitive in terms of shoot growth. Collectively the data suggests that FAAH activity may interact with stress-responsive pathways in plants, perhaps including pathways involving ABA.
Date: May 2012
Creator: Gonzalez, Gabriel
Partner: UNT Libraries

Ota-quadrotor: An Object-tracking Autonomous Quadrotor for Real-time Detection and Recognition

Description: The field of robotics and mechatronics is advancing at an ever-increasing rate and we are starting to see robots making the transition from the factories to the workplace and homes as cost is reduced and they become more useful. In recent years quadrotors have become a popular unmanned air vehicle (UAV) platform. These UAVs or micro air vehicles (MAV) are being used for many new and exciting applications such as aerial monitoring of wildlife, disaster sites, riots and protests. They are also being used in the film industry, as they are significantly cheaper means of getting aerial footage. While quadrotors are not extremely expensive a good system can cost in the range of $3000 - $8000 and thus too costly as a research platform for many. There are a number of cheaper open source platforms. The ArduCopter is under constant development, has the largest community and is inexpensive making it an ideal platform to work with. The goal of this thesis was to implement video processing on a ground control station allowing for the ArduCopter to track moving objects. This was achieved by using the OpenCV video-processing library to implement object tracking and the MAVLink communication protocol, available on the ArduCopter platform, for communication.
Date: May 2012
Creator: Coelho, Gavin
Partner: UNT Libraries

Forgiveness and Loneliness: Stress and Anxiety’s Correlates in a Student and Clinical Hiv-positive Sample

Description: Persistent periods of stress exacerbate the symptoms of chronic illness. Additionally, loneliness is strongly correlated with stress and both state and trait anxiety. Prolonged periods of loneliness are linked with depression in both clinical and student samples. Forgiveness, a cognitive, emotional, and behavioral response to interpersonal or intrapersonal conflict, is important to social harmony. in this study I describe three studies that examine forgiveness, loneliness, stress, and anxiety in two populations, a student population and an HIV+ clinical population. Study 1 examined how the variables of forgiveness and loneliness are associated with perceived stress in a student sample of undergraduate students. Study 2 examined the same variables (forgiveness, loneliness, and perceived stress) in an HIV-positive clinical population. Finally, study 3 extends the model and examines the relationship of forgiveness and loneliness to variables related to stress, state and trait anxiety. for studies 2 and 3, 63 HIV-positive individuals participated in the cross-sectional correlational study. the data was analyzed in each study using hierarchical linear regression analysis. We also tested the models for the three studies to determine if forgiveness moderates the relationship between loneliness and state and trait anxiety. in study 1, using hierarchical linear regression analyses, I found that increased forgiveness and decreased loneliness was associated with less perceived stress in both a non-clinical and clinical sample of HIV-positive adults. in studies 2 and 3, I conducted hierarchical linear regression analyses and found that increased forgiveness contributed a significant portion of the variance in perceived stress and state and trait anxiety in a non-clinical and HIV-positive sample. I did not find moderation in any of the models.
Date: May 2012
Creator: Hill, Jonathan
Partner: UNT Libraries

Mental Toughness: An Analysis of Sex, Race, and Mood

Description: Mental toughness has become a focus for researchers as coaches, athletes, and others extol its influence in performance success. In this study I examined mental toughness among collegiate athletes, focusing on its potential relationship to different demographic variables and to the athletes’ mood. Two hundred seventy-two student-athletes representing 12 different sports from a southwestern NCAA Division I university, participated by completing the Sports Mental Toughness Questionnaire (SMTQ), the Brief Assessment of Mood (BAM), and providing demographic information. Analyses of variance (ANOVA) assessed differences in mental toughness scores by sex, race, scholarship status, and starting status. Significant differences in mental toughness emerged between Black – White, male – female, and full – partial – zero scholarship athletes. Pearson correlations showed mental toughness was significantly related to lower levels of anxiety, sadness, anger, confusion, fatigue, and total mood disturbance, and higher levels of vigor.
Date: May 2012
Creator: Beck, Nicholas M.
Partner: UNT Libraries

Never Odd Or Even: Using Temporal Structures In Composing Music For Dance

Description: This study engages the collaboration of dance and music, focusing primarily on experiences in the production of a large scale collaborative concert entitled Never Odd or Even. Famous historical collaborations offer archetypal collaborative models, the more unconventional of which are applied to the pieces of the concert. Issues and observations regarding cross-influence, project evolution, and application of the collaborative models are engaged to determine effective means of collaboration given different circumstances. The key focus of the study, the temporal relationship between music and dance, is explored in great detail to determine three models for relating time between music and dance. These temporal relationship models are applied to the pieces and evaluated on effectiveness and potential strengths when applied to dance.
Date: May 2012
Creator: Bernardo, Daniel
Partner: UNT Libraries

A Multiscalar Analysis of Buruli Ulcer in Ghana: Environmental and Behavioral Factors in Disease Prevalence

Description: Buruli ulcer (BU), an infectious disease caused by Mycobacterium ulcerans, is the third most common mycobacterial disease after leprosy and tuberculosis and a WHO-defined neglected tropical disease. Despite years of research, the mode of transmission of BU remains unknown. This master’s thesis provides an integrated spatial analysis of disease dynamics in Ghana, West Africa, an area of comparatively high BU incidence. Within a case/matched control study design, environmental factors associated with BU infection and spatial behaviors are investigated to uncover possible links between individual daily activity spaces and terrains of risk across disturbed landscapes. This research relies upon archival and field-collected data and analyses conducted with geographical information systems (GIS).
Date: May 2012
Creator: Ferring, David
Partner: UNT Libraries

Spatial Analysis of Hiv/aids Survival in Dallas and Harris Counties, Texas

Description: More Texans are living with HIV infection than ever before. in fact, there has been a 6% increase annually, since 2002. This trend is not a result of increased HIV/AIDS incidence, but rather improving life expectancy of those living with HIV. Due to significant advances in HIV/AIDS testing, prevention, and treatment, individuals with HIV are living longer than ever before. However, throughout the state, the life expectancy of a person infected with HIV/AIDS varies spatially. This study investigates and attempts to explain the spatial distribution of HIV/AIDS survival rates by examining neighborhood socioeconomic characteristics. the results suggest that, contrary to expectation, the lowest survival rates occur, not in extreme poverty areas, but rather in moderate SES areas. Too rich to qualify for free treatments, but not rich enough to afford purchasing such treatments, the middle income living with HIV infection are caught between the cracks. the results provide important input for targeting public health interventions to improve HIV/AIDS survival.
Date: May 2012
Creator: Heald, Stephanie
Partner: UNT Libraries