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Jacques-Antoine-Hippolyte, Comte De Guibert: Father of the Grande Armée

Description: Jacques-Antoine-Hippolyte, comte de Guibert (1743-1790) dedicated his life and career to creating a new doctrine for the French army. Little about this doctrine was revolutionary. Indeed, Guibert openly decried the anarchy of popular participation in government and looked askance at the early days of the Revolution. Rather, Guibert’s doctrine marked the culmination of an evolutionary process that commenced decades before his time and reached fruition in the Réglement of 1791, which remained in force until the 1830s. Not content with military reform, Guibert demanded a political and social constitution to match. His reforms required these changes, demanding a disciplined, service-oriented society and a functional, rational government to assist his reformed military. He delved deeply, like no other contemporary writer, into the linkages between society, politics, and the military throughout his career and his writings. Guibert exerted an overwhelming influence on military thought across Europe for the next fifty years. His military theories provided the foundation for military reform during the twilight of the Old Regime. The Revolution, which adopted most of Guibert’s doctrine in 1791, continued his work. A new army and way of war based on Guibert’s reforms emerged to defeat France’s major enemies. In Napoleon’s hands, Guibert’s army all but conquered Europe by 1807. As other nations adopted French methods, Guibert’s influence spread across the Continent, reigning supreme until the 1830s. This dissertation adopts a biographical approach to examine Guibert’s life and influence on the creation of the French military system that led to Napoleon’s conquest of Europe. As no such biography exists in Anglophone literature, such a work will fill a crucial gap in understanding French military success to 1807. It examines the period of French military reform from 1760 to the creation and use of Napoleon’s Grande Armée from 1803 to 1807, illustrating the importance of ...
Date: August 2014
Creator: Abel, Jonathan, 1985-
Partner: UNT Libraries

Boosting for Learning From Imbalanced, Multiclass Data Sets

Description: In many real-world applications, it is common to have uneven number of examples among multiple classes. The data imbalance, however, usually complicates the learning process, especially for the minority classes, and results in deteriorated performance. Boosting methods were proposed to handle the imbalance problem. These methods need elongated training time and require diversity among the classifiers of the ensemble to achieve improved performance. Additionally, extending the boosting method to handle multi-class data sets is not straightforward. Examples of applications that suffer from imbalanced multi-class data can be found in face recognition, where tens of classes exist, and in capsule endoscopy, which suffers massive imbalance between the classes. This dissertation introduces RegBoost, a new boosting framework to address the imbalanced, multi-class problems. This method applies a weighted stratified sampling technique and incorporates a regularization term that accommodates multi-class data sets and automatically determines the error bound of each base classifier. The regularization parameter penalizes the classifier when it misclassifies instances that were correctly classified in the previous iteration. The parameter additionally reduces the bias towards majority classes. Experiments are conducted using 12 diverse data sets with moderate to high imbalance ratios. The results demonstrate superior performance of the proposed method compared to several state-of-the-art algorithms for imbalanced, multi-class classification problems. More importantly, the sensitivity improvement of the minority classes using RegBoost is accompanied with the improvement of the overall accuracy for all classes. With unpredictability regularization, a diverse group of classifiers are created and the maximum accuracy improvement reaches above 24%. Using stratified undersampling, RegBoost exhibits the best efficiency. The reduction in computational cost is significant reaching above 50%. As the volume of training data increase, the gain of efficiency with the proposed method becomes more significant.
Date: December 2013
Creator: Abouelenien, Mohamed
Partner: UNT Libraries

Cooperative Strategy and Sources of Knowledge Integration Capability and Innovation: A Relational View

Description: Faced with the challenges to addressing the novelties of the changing business environments (e.g., new customer requirement, changes in customers taste and preferences, the introduction of new products or services by competitors), organizations seek to build collaboration among their employees who possess complementary knowledge. Integrating complementary knowledge enhances employees' ability to address environmental challenges and foster innovation. Despite the importance of knowledge integration for innovation, integration of such knowledge becomes difficult when employees lack a shared understanding of knowledge, and when the knowledge is newly generated. Because new knowledge is tacit in nature and highly personal to a particular individual, it is difficult to articulate, making knowledge integration (KI) an arduous task. Lack of shared understanding, the presence of new knowledge, and lack of common interests in employees creates three types of knowledge boundaries – syntactic (information processing) boundaries, semantic (interpretive) boundaries, and pragmatic (political) boundaries. The presence of knowledge boundaries makes it difficult for employees to share and access their knowledge with each other. To overcome the challenges related to the knowledge boundaries, employees use boundary-spanning objects, which are common lexicons, common meaning, and common interests, to share and access their knowledge across the boundaries. Although prior studies have emphasized the importance of knowledge integration of various knowledge sources for innovations, examinations of what enhances KI capability of employees for organizational innovation remain limited. In addition, apart from Carlile, (2004) and Franco (2013), which are both case studies, other studies that examine the role of boundary spanning objects for knowledge integration are missing. The knowledge management literature also fails to measures (the success of common lexicons, common meaning, and common interests for achieving KI capability) boundary spanning objects. Therefore, in this study, new measurement items of boundary spanning objects and novelty are developed to test the hypotheses. A survey-based ...
Date: August 2016
Creator: Acharya, Chandan
Partner: UNT Libraries

New Frameworks for Secure Image Communication in the Internet of Things (IoT)

Description: The continuous expansion of technology, broadband connectivity and the wide range of new devices in the IoT cause serious concerns regarding privacy and security. In addition, in the IoT a key challenge is the storage and management of massive data streams. For example, there is always the demand for acceptable size with the highest quality possible for images to meet the rapidly increasing number of multimedia applications. The effort in this dissertation contributes to the resolution of concerns related to the security and compression functions in image communications in the Internet of Thing (IoT), due to the fast of evolution of IoT. This dissertation proposes frameworks for a secure digital camera in the IoT. The objectives of this dissertation are twofold. On the one hand, the proposed framework architecture offers a double-layer of protection: encryption and watermarking that will address all issues related to security, privacy, and digital rights management (DRM) by applying a hardware architecture of the state-of-the-art image compression technique Better Portable Graphics (BPG), which achieves high compression ratio with small size. On the other hand, the proposed framework of SBPG is integrated with the Digital Camera. Thus, the proposed framework of SBPG integrated with SDC is suitable for high performance imaging in the IoT, such as Intelligent Traffic Surveillance (ITS) and Telemedicine. Due to power consumption, which has become a major concern in any portable application, a low-power design of SBPG is proposed to achieve an energy- efficient SBPG design. As the visual quality of the watermarked and compressed images improves with larger values of PSNR, the results show that the proposed SBPG substantially increases the quality of the watermarked compressed images. Higher value of PSNR also shows how robust the algorithm is to different types of attack. From the results obtained for the energy- efficient SBPG ...
Date: August 2016
Creator: Albalawi, Umar Abdalah S
Partner: UNT Libraries

Development of an Instrument to Measure the Level of Acceptability and Tolerability of Cyber Aggression: Mixed-Methods Research on Saudi Arabian Social Media Users

Description: Cyber aggression came about as a result of advances in information communication technology and the aggressive usage of the technology in real life. Cyber aggression can take on many forms and facets. However, the main focus of this study is cyberbullying and cyberstalking through information sharing practices that might constitute digital aggressive acts. Human aggression has been extensively investigated. Studies focusing on understanding the causes and effects that can lead to physical and digital aggression have shown the prevalence of cyber aggression in different settings. Moreover, these studies have shown strong relationship between cyber aggression and the physiological and physical trauma on both perpetrators and their victims. Nevertheless, the literature shows a lack of studies that could measure the level of acceptance and tolerance of these dangerous digital acts. This study is divided into two main stages; Stage one is a qualitative pilot study carried out to explore the concept of cyber aggression and its existence in Saudi Arabia. In-depth interviews were conducted with 14 Saudi social media users to collect understanding and meanings of cyber aggression. The researcher followed the Colaizzi’s methods to analyze the descriptive data. A proposed model was generated to describe cyber aggression in social media applications. The results showed that there is a level of acceptance to some cyber aggression acts due to a number of factors. The second stage of the study is focused on developing scales with reliable items that could determine acceptability and tolerability of cyber aggression. In this second stage, the researcher used the factors discovered during the first stage as source to create the scales’ items. The proposed methods and scales were analyzed and tested to increase reliability as indicated by the Cronbach’s Alpha value. The scales were designed to measure how acceptable and tolerable is cyber-bullying, cyber-stalking in Saudi ...
Date: May 2016
Creator: Albar, Ali A
Partner: UNT Libraries

Decision Makers’ Cognitive Biases in Operations Management: An Experimental Study

Description: Behavioral operations management (BOM) has gained popularity in the last two decades. The main theme in this new stream of research is to include the human behavior in Operations Management (OM) models to increase the effectiveness of such models. BOM is classified into 4 areas: cognitive psychology, social psychology, group dynamics and system dynamics (Bendoly et al. 2010). This dissertation will focus on the first class, namely cognitive psychology. Cognitive psychology is further classified into heuristics and biases. Tversky and Kahneman (1974) discussed 3 heuristics and 13 cognitive biases that usually face decision makers. This dissertation is going to study 6 cognitive biases under the representativeness heuristic. The model in this dissertation states that cognitive reflection of the individual (Frederick 2005) and training about cognitive biases in the form of warning (Kaufmann and Michel 2009) will help decisions’ makers make less biased decisions. The 6 cognitive biases investigated in this dissertation are insensitivity to prior probability, insensitivity to sample size, misconception of chance, insensitivity to predictability, the illusion of validity and misconception of regression. 6 scenarios in OM contexts have been used in this study. Each scenario corresponds to one cognitive bias. Experimental design has been used as the research tool. To see the impact of training, one group of the participants received the scenarios without training and the other group received them with training. The training consists of a brief description of the cognitive bias as well as an example of the cognitive bias. Cognitive reflection is operationalized using cognitive reflection test (CRT). The survey was distributed to students at University of North Texas (UNT). Logistic regression has been employed to analyze data. The research shows that participants show the cognitive biases proposed by Tversky and Kahneman. Moreover, CRT is significant factor to predict the cognitive bias in two ...
Date: May 2016
Creator: Alkhars, Mohammed
Partner: UNT Libraries

Customers' Attitudes toward Mobile Banking Applications in Saudi Arabia

Description: Mobile banking services have changed the design and delivery of financial services and the whole banking sector. Financial service companies employ mobile banking applications as new alternative channels to increase customers' convenience and to reduce costs and maintain profitability. The primary focus of this study was to explore the Saudi bank customers' perceptions about the adoption of mobile banking applications and to test the relationships between the factors that influence mobile banking adoption as independent variables and the action to adopt them as the dependent variable. Saudi customers' perceptions were tested based on the extended versions of IDT, TAM and other diffusion of innovation theories and frameworks to generate a model of constructs that can be used to study the use and the adoption of mobile technology by users. Koenig-Lewis, Palmer, & Moll's (2010) model was used to test its constructs of (1) perceived usefulness, (2) perceived ease of use, (3) perceived compatibility, (4) perceived credibility, (5) perceived trust, (6) perceived risk, and (7) perceived cost, and these were the independent variables in current study. This study revealed a high level of adoption that 82.7% of Saudis had adopted mobile banking applications. Also, the findings of this study identified a statistically significant relationship between all of demographic differences: gender, education level, monthly income, and profession and mobile banking services among adopters and non-adopters. Seven attributes relating to the adoption of mobile banking applications were evaluated in this study to assess which variables affected Saudi banks customers in their adoption of mobile banking services. The findings indicated that the attributes that significantly affected the adoption of mobile banking applications among Saudis were perceived trust, perceived cost, and perceived risk. These three predictors, as a result, explained more than 60% of variance in intention to adopt mobile banking technology in Saudi Arabia. ...
Date: August 2016
Creator: Alshara, Mohammed Ali
Partner: UNT Libraries

Novel Role of Trypsin in Zebrafish

Description: It has been shown previously in our laboratory that zebrafish produce trypsin from their gills when they are under stress, and this trypsin is involved in thrombocyte activation via PAR2 during gill bleeding. In this study, I investigated another role of the trypsin that is secreted from zebrafish. This investigation has demonstrated a novel role of trypsin in zebrafish. Not only did this investigation demonstrate the role of trypsin in zebrafish behavior, but also it showed that PAR2 might be the receptor that is involved in trypsin-mediated behavioral response. In addition, we have shown that Gq and ERK inhibitors are able to block the trypsin pathway and prevent the escaping behavior. Finally, the results of this investigation suggest that the cells that respond to trypsin are surface cells, which have an appearance similar to that of neuromast cells.
Date: May 2013
Creator: Alsrhani, Abdullah Falleh
Partner: UNT Libraries

Health-related Quality of Life and Social Engagement in Assisted Living Facilities

Description: This research project aims to clarify the factors that impact successful aging in Assisted Living facilities (ALFs) in Denton County, Texas. We hypothesize that social disengagement decreases physical and mental components of quality of life. This exploratory research project employed standardized questionnaires to assess residents in the following domains; HRQOL, social engagement status, level of cognition, depression, and the level of functioning. This study collected data from 75 participants living in five ALFs. The average of Physical Component Scale (PCS) and Mental Component Scale (MCS) was 35.33, and 53.62 respectively. None of the participants had five or more social contacts out of facilities, and two-third of them had two or less social contacts. On average, those participants who were more socially engaged had higher score of MCS compared with disengaged counterparts. The level of physical function significantly affects social engagement, when people with more disabilities are more likely to be socially disengaged. Social engagement and depression significantly impact MCS, when depression is a mediating factor between social engagement and mental component of quality of life. Considering the expansion in aging population in the United States within the next three decades, the demand for high quality long-term care will skyrocket consequently. This study reveals that external social engagement can sustain HRQOL of residents in assisted living facilities.
Date: August 2015
Creator: Amini, Reza
Partner: UNT Libraries

Effect of Acute Alcohol Ingestion on Resistance Exercise Induced Mtorc1 Signaling in Human Muscle

Description: The purpose of this project was to further elucidate the effects post-exercise alcohol ingestion. This project had many novel aspects including using a resistance exercise (RE) only exercise design and the inclusion of women. To our knowledge, we are the first to investigate the effect of post-RE alcohol ingestion in women. In the first chapter of this project, information on the prevalence of alcohol use and the importance of skeletal muscle as a dynamic and metabolic tissue was provided. In chapter two, the effects of post-RE alcohol ingestion in men and women are detailed. The major findings of this study was that although RE elicited similar mTORC1 signaling both in men and in women, alcohol ingestion appeared to only attenuate RE-induced phosphorylation of the mTORC1 signaling pathway in men. The third chapter focused on examining the effects of post-RE alcohol ingestion on acute testosterone bioavailability. The primary findings of this study was that alcohol substantially elevated serum total and free testosterone concentrations during recovery from a bout of resistance exercise. The fourth chapter detailed factors that contribute to bone density in men. The major findings of this study was that young adult male long-distance runners who participated in resistance training at least once per week had greater bone mineral density than their non-resistance trained and non-exercise trained peers.
Date: August 2015
Creator: Anthony A. Duplanty
Partner: UNT Libraries

A Guide to Arranging Late Eighteenth and Early Nineteenth Century Harmoniemusik in an Historical Style

Description: The wind octet was a popular ensemble of the classical period. In 1782, the Viennese Emperor formed a wind octet which specialized in playing opera arrangements. This music was used primarily as a form of background entertainment for dinners. This guide analyzes and compares the works of several well-known arrangers from the classical period in order to demonstrate arranging styles of the time. The arrangers of the period were often the performers of these various wind octets who were writing specifically for the players in their own ensembles. The style of Mozart’s original wind music is also discussed, in contrast to the arrangements of his works made by others. This guide is intended for serve performers of today as a tool to learn the art of arranging in an historical style. Idiosyncrasies of the classical-period wind instruments are discussed, as they relate to the style of wind arranging. The role of the contemporary arranger is compared with that of the classical period, and the case is made for the need for more contemporary arrangements of classical works using period arrangers as models.
Date: August 2015
Creator: April Marie Ross
Partner: UNT Libraries

Space and Spectrum Engineered High Frequency Components and Circuits

Description: With the increasing demand on wireless and portable devices, the radio frequency front end blocks are required to feature properties such as wideband, high frequency, multiple operating frequencies, low cost and compact size. However, the current radio frequency system blocks are designed by combining several individual frequency band blocks into one functional block, which increase the cost and size of devices. To address these issues, it is important to develop novel approaches to further advance the current design methodologies in both space and spectrum domains. In recent years, the concept of artificial materials has been proposed and studied intensively in RF/Microwave, Terahertz, and optical frequency range. It is a combination of conventional materials such as air, wood, metal and plastic. It can achieve the material properties that have not been found in nature. Therefore, the artificial material (i.e. meta-materials) provides design freedoms to control both the spectrum performance and geometrical structures of radio frequency front end blocks and other high frequency systems. In this dissertation, several artificial materials are proposed and designed by different methods, and their applications to different high frequency components and circuits are studied. First, quasi-conformal mapping (QCM) method is applied to design plasmonic wave-adapters and couplers working at the optical frequency range. Second, inverse QCM method is proposed to implement flattened Luneburg lens antennas and parabolic antennas in the microwave range. Third, a dual-band compact directional coupler is realized by applying artificial transmission lines. In addition, a fully symmetrical coupler with artificial lumped element structure is also implemented. Finally, a tunable on-chip inductor, compact CMOS transmission lines, and metamaterial-based interconnects are proposed using artificial metal structures. All the proposed designs are simulated in full-wave 3D electromagnetic solvers, and the measurement results agree well with the simulation results. These artificial material-based novel design methodologies pave the way ...
Date: May 2015
Creator: Arigong, Bayaner
Partner: UNT Libraries

Witchcraft: a Targeted Societal Discrimination Against Women in Northern Ghana

Description: A combination of aging and poverty is becoming dominant in African society today, at a time when African countries are expected to be recovering from poverty, and are projected to house the economic growth of the next century. The emergence of aging in African context and the aging of the world population will expose the weakness of the current mechanisms used for older people around the world. As economies grow around the world, the distribution gap between the affluent and the poor widens, and the constant struggles for wealth, power, and social status, amidst scarce resources, continue to be sustained. To remain in charge of economic resources, the powerful few devise means to disenfranchise the weak, and witchcraft accusation is one of such tools used in Northern Ghana today. A new wave of witchcraft accusation has caught the attention of many in Northern Ghana. These victims with certain socioeconomic characteristics appear helpless and without defense against such accusations. As a result, they suffer untold hardships and are often compelled to leave their homes and to reside in camps reserved for witches. This study was undertaken to identify those sociodemographic characteristics, which are commonly shared by witchcraft accusation victims. These sociodemographic characteristics can be used to predict those who are most likely to be discriminated against using accusations of witchcraft in Northern Ghana. As age places more strain on existing systems and as more people survive into old age with inadequate healthcare, more accusations may be predicted to occur against the elderly, unless enough government intervention is used to address the present redistribution of income in third world countries.
Date: December 2013
Creator: Atumah, Oscar Nwagbo
Partner: UNT Libraries

Functional Characterization of Mtnip/latd’s Biochemical and Biological Function

Description: Symbiotic nitrogen fixation occurs in plants harboring nitrogen-fixing bacteria within the plant tissue. The most widely studied association is between the legumes and rhizobia. In this relationship the plant (legumes) provides the bacteria (rhizobia) with reduced carbon derived from photosynthesis in exchange for reduced atmospheric nitrogen. This allows the plant to survive in soil, which is low in available of nitrogen. Rhizobia infect and enter plant root and reside in organs known as nodules. In the nodules the bacteria fix atmospheric nitrogen. The association between the legume, Medicago truncatula and the bacteria Sinorhizobium meliloti, has been studied in detail. Medicago mutants that have defects in nodulation help us understand the process of nitrogen fixation better. One such mutant is the Mtnip-1. Mtnip-1 plants respond to S. meliloti by producing abnormal nodules in which numerous aberrant infection threads are produced, with very rare rhizobial release into host plant cells. The mutant plant Mtnip-1 has an abnormal defense-like response in root nodules as well as defects in lateral root development. Three alleles of the Mtnip/latd mutants, Mtnip-1, Mtlatd and Mtnip-3 show different degrees of severity in their phenotype. Phylogenetic analysis showed that MtNIP/LATD encodes a protein belonging to the NRT1(PTR) family of nitrate, peptide, dicarboxylate and phytohprmone transporters. Experiments with Mtnip/latd mutants demonstrats a defective nitrate response associated with low (250 μM) external nitrate concentration rather than high (5 mM) nitrate concentration. This suggests that the mutants have defective nitrate transport. To test if MtNIP/LATD was a nitrate transporter, Xenopus laevis oocytes and Arabidopsis thaliana mutant plants Atchl1-5, defective in a major nitrate transporter AtNRT1.1(CHL1), were used as surrogate expression systems. Heterologous expression of MtNIP/LATD in X. laevis oocytes and Atchl1-5 mutant plants conferred on them the ability to take up nitrate from external media with high affinity, thus demonstrating that MtNIP/LATD ...
Date: December 2013
Creator: Bagchi, Rammyani
Partner: UNT Libraries

Eight-Year Course of Cognitive Functioning in Bipolar Disorder with Psychotic Features

Description: The purpose of the current study was to examine neuropsychological functioning in patients with bipolar disorder (BD) with psychotic features. Data from a large, epidemiological study of patients with first-episode psychosis was used to examine verbal learning and working memory 10 years after onset of psychosis in patients with BD relative to patients with schizophrenia (SZ) and patients with psychotic major depressive disorder (MDD). Cross-sectional comparisons of verbal learning and working memory at the 10-year follow-up mirrored findings of relative performance at the 2-year follow-up (Mojtabai, 2000), as patients with SZ performed significantly worse than patients with psychotic affective disorders. When FEP patients' cognitive performance was examined longitudinally, all groups showed non-significant decline over time, with no significant diagnostic group differences after accounting for current symptoms. More frequent hospitalizations and longer treatment with antipsychotics were associated with poorer performance on cognitive testing 10 years after illness onset, but these associations disappeared when controlling baseline cognitive performance. Within the BD sample, current positive and negative psychotic symptoms were associated with poorer performance on cognitive testing. After controlling for baseline cognitive performance, markers of clinical course were unrelated to cognitive performance, consistent with existing literature on longitudinal cognitive functioning in patients with BD. The current findings support a neurodevelopmental model of verbal learning and working memory deficits in patients with bipolar disorder.
Date: August 2016
Creator: Bain, Kathleen Marie
Partner: UNT Libraries

Sensing and Decoding Brain States for Predicting and Enhancing Human Behavior, Health, and Security

Description: The human brain acts as an intelligent sensor by helping in effective signal communication and execution of logical functions and instructions, thus, coordinating all functions of the human body. More importantly, it shows the potential to combine prior knowledge with adaptive learning, thus ensuring constant improvement. These qualities help the brain to interact efficiently with both, the body (brain-body) as well as the environment (brain-environment). This dissertation attempts to apply the brain-body-environment interactions (BBEI) to elevate human existence and enhance our day-to-day experiences. For instance, when one stepped out of the house in the past, one had to carry keys (for unlocking), money (for purchasing), and a phone (for communication). With the advent of smartphones, this scenario changed completely and today, it is often enough to carry just one's smartphone because all the above activities can be performed with a single device. In the future, with advanced research and progress in BBEI interactions, one will be able to perform many activities by dictating it in one's mind without any physical involvement. This dissertation aims to shift the paradigm of existing brain-computer-interfaces from just ‘control' to ‘monitor, control, enhance, and restore' in three main areas - healthcare, transportation safety, and cryptography. In healthcare, measures were developed for understanding brain-body interactions by correlating cerebral autoregulation with brain signals. The variation in estimated blood flow of brain (obtained through EEG) was detected with evoked change in blood pressure, thus, enabling EEG metrics to be used as a first hand screening tool to check impaired cerebral autoregulation. To enhance road safety, distracted drivers' behavior in various multitasking scenarios while driving was identified by significant changes in the time-frequency spectrum of the EEG signals. A distraction metric was calculated to rank the severity of a distraction task that can be used as an intuitive measure ...
Date: August 2016
Creator: Bajwa, Garima
Partner: UNT Libraries

American Indian Worldviews, Risk Perceptions and Disaster Planning: an Exploratory Study

Description: It is commonly assumed that when confronted with an imminent hazard that people will react rationally, and prepare for, or at least attempt to avoid, danger from pending disasters. However, this conventional wisdom is not as evident as it appears. People prepare for, react to, or take social action to avoid hazards when they perceive the risk of danger to be threatening enough to warrant action, providing one has the will, insight and resources to do so. However, not all people perceive risks similarly. Risk is perceived differently by different people which affects risk perception and responses to hazards. This dissertation explores the relationships between American Indian worldviews, risk perceptions and disaster planning. To carry out this research 28 American Indians were interviewed. The sample consists of 14 American Indians residing in a rural are on the northern plains and 14 urban American Indians. The results only partially support that worldview is linked to risk perception and subsequent disaster planning. Other factors found to relate to risk perception and disaster planning for this non-representative sample of American Indians include various forms of social vulnerability.
Date: December 2013
Creator: Bales, Rodney A.
Partner: UNT Libraries

Synthesis and Photochemical Studies of Wide-Band Capturing Sensitizers Capable of Light Energy Harvesting

Description: Artificial photosynthesis, for the purpose of converting solar energy into fuel, is one of the most viable and promising alternative approaches to solve the current global energy and environmental issues. Among the challenges faced in artificial photosynthesis is in building photosystems that can effectively and efficiently perform light absorption and charge separation in broad-band capturing donor-acceptor systems. While having a broad-band capturing antenna system that can harness incoming photons is crucial, another equally important task is to successfully couple the antenna system, while maintaining its optical properties, to an energy or electron acceptor which serves as the reaction center for the generation of charged species of useful potential energy. The stored potential energy will be utilized in different applications such as driving electrons in solar cells or in splitting water for the generation of fuel. Hence, the particular endeavor of this thesis is to study and synthesize molecular/supramolecular systems with wide-band capturing capabilities to generate long-lived charge separated states. The sensitizer used in building these systems in the present study is 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene, for short, BF2 chelated Azaboron dipyrromenthene or AzaBODIPY. A handful of novel donor-acceptor systems based on AzaBODIPY have been successfully designed, synthesized and their photochemistry have been investigated using various techniques. In these systems, Azabodipy has been covalently attached to several donors like porphyrin, bodipy, subphthalocyanine, phenothiazine, ferrocene, bithiophene and effectively coupled to an electron acceptor, C60. These systems have been fully characterized by NMR, Mass, optical absorption and emission, X-ray crystallographic, computational, electrochemical, and photochemical studies. It has been possible to demonstrate occurrence of efficient electron and energy transfer events and long-lived charge separated states upon photoexcitation in these model compounds. By changing the arrangements of the donor and acceptor entities, it has also been possible to show directional, through-space and through-bond electron transfer processes. The present ...
Date: August 2016
Creator: Bandi, Venu Gopal
Partner: UNT Libraries

Application of Cyclic Polarization of Aluminum 3003 Used in All-Aluminum Microchannel Heat Exchangers

Description: All-aluminum microchannel heat exchangers are designed to significantly reduce refrigerant charge requirements, weight, reduced brazed joints, and decreased potential for leakage by increasing reliability. Al 3003 alloy is corrosion resistant and can be formed, welded, and brazed but the issue with all-aluminum heat exchangers is localized corrosion (pitting) in corrosive environments. Currently, there is no universally accepted corrosion test that all coil manufacturers use to characterize their products. Electrochemical testing method of cyclic polarization was employed in this investigation and relevant parameters including electrolyte corrosive agent and its concentration, electrolyte pH, and applied potential scan rate was varied to find an optimal set of parameters. Results of cyclic polarization of Al 3003 in electrolytes containing various concentrations of NaCl were compared with those of the tests in Sea Water Acidified Accelerated Test (SWAAT) electrolyte and it is shown the SWAAT electrolyte (4.2% sea salt acidified to pH of 2.9) is by far stronger (in terms of corrosivity) than typical 3.5% NaCl solution used in most corrosion testing. Corrosion rates (g/m2yr) of Al 3003 measured in this investigation were comparable to those provided by ISO 9223 standard corresponding to C1 through CX categories. Duration of cyclic polarization test is much shorter than that of SWAAT and results obtained in this test is more reproducible compared to those of SWAAT. Scanning electron microscopy micrographs show typical pit depths of about 50 μm.
Date: May 2015
Creator: Barnes, Javier
Partner: UNT Libraries

The “Nigger Trinity”: Engaging the Discourse in Post Civil Rights/Post 1960s America

Description: The cultural and popular media landscape of the United States of America changed after the Civil-Rights movement of the 1960s. The word “Nigger” was changed during that same period of American history. There are several authors and a comic that helped change this word during the 1960s. The post Civil-Rights American has a different experience and understanding with this word than those born before 1970. This work triangulates the current cultural location of the word “Nigger,” “nigga,” and “the n-word” using linguistics, law, and two media case studies. The “Nigger” trinity is a model that adds value to the discourse that surrounds this one word in post civil-rights/post 1960s America.
Date: December 2011
Creator: Bell, Adrian Shane
Partner: UNT Libraries

Characteristics of Primary Cilia and Centrosomes in Neuronal and Glial Lineages of the Adult Brain

Description: Primary cilia are sensory organelles that are important for initiating cell division in the brain, especially through sonic hedgehog (Shh) signaling. Several lines of evidence suggest that the mitogenic effect of Shh requires primary cilia. Proliferation initiated by Shh signaling plays key roles in brain development, in neurogenesis in the adult hippocampus, and in the generation of glial cells in response to cortical injury. In spite of the likely involvement of cilia in these events, little is known about their characteristics. Centrosomes, which are associated with primary cilia, also have multiple influences on the cell cycle, and they are important in assembling microtubules for the maintenance of the cell’s cytoskeleton and cilia. The cilia of terminally differentiated neurons have been previously examined with respect to length, incidence, and receptors present. However, almost nothing is known about primary cilia in stem cells, progenitors, or differentiated glial cells. Moreover, it is not known how the properties of cilia and centrosomes may vary with cell cycle or proliferative potential, in brain or other tissues. This dissertation focuses first on neurogenesis in the hippocampal subgranular zone (SGZ). The SGZ is one of the few brain regions in mammals that gives rise to a substantial number of new neurons throughout adulthood. The neuron lineage contains a progression of identifiable precursor cell types with different proliferation rates. This present study found that primary cilia were present in every cell type in the neuronal lineage in SGZ. Cilium length and incidence were positively correlated among these cell types. Ciliary levels of adenylyl cyclase type III (ACIII) levels relative to ADP-ribosylation factor-like protein 13b (Arl13b) was higher in neurons than in precursor cells and glia, and also changed with the cell cycle. G-protein coupled receptors, SstR3, MCHR1, and Gpr161 receptors were only found in neuronal cilia. The levels ...
Date: May 2015
Creator: Bhattarai, Samip Ram
Partner: UNT Libraries

Between Comancheros and Comanchería: a History of Fort Bascom, New Mexico

Description: In 1863, Fort Bascom was built along the Canadian River in the Eroded Plains of Territorial New Mexico. Its unique location placed it between the Comanches of Texas and the Comancheros of the Sangre de Cristo Mountains. This post was situated within Comanchería during the height of the United States Army's war against the Southern Plains Indians, yet it has garnered little attention. This study broadens the scholarly understanding of how the United States Army gained control of the Southwest by examining the role Fort Bascom played in this mission. This includes an exploration of the Canadian River Valley environment, an examination of the economic relationship that existed between the Southern Plains Indians and the mountain people of New Mexico, and an account of the daily life of soldiers posted to Fort Bascom. This dissertation thus provides an environmental and cultural history of the Canadian River Valley in New Mexico, a social history of the men stationed at Fort Bascom, and proof that the post played a key role in the Army's efforts to gain control of the Southern Plains Indians. This study argues that Fort Bascom should be recognized as Texas' northern-most frontier fort. Its men were closer to the Comanche homeland than any Texas post of the period. Its records clearly show that the Army used Fort Bascom as a key forward base of operations against Comanches and Kiowas. An examination of Bascom's post returns, daily patrols, and major expeditions allows its history to provide a useful perspective on the nineteenth-century American Southwest.
Date: August 2012
Creator: Blackshear, James Bailey
Partner: UNT Libraries

"This Fundamental Lack": Stories

Description: This short story collection includes five original works of fiction, three of which make up a trilogy titled "The World Drops Beneath You," which follows the life of James McClellan from 1969 in Texas until roughly 2009, when he is struggling to care for his wife, who suffers from Alzheimer's disease. One of the two remaining stories, "She Loved Him When He Looked Like Elvis," prominently features James McClellan's parents and is set approximately eight years before the start of the trilogy. Each of the stories is concerned with blue-collar families trying to make their way in postindustrial America and the forces that buffet them, including some brought on by the choices they make.
Date: August 2016
Creator: Bohanan, Ronal L.
Partner: UNT Libraries

Role of Gpr17 in Thrombocyte Aggregation in Adult Zebrafish

Description: GPR17, a uracil nucleotide cysteinyl leukotriene receptor, belongs to the GPCR (G protein coupled receptor) family. It has been shown recently that inhibiting this protein in the nervous system in mice can lead to blockage of oligodendrocyte maturation, which supports myelin repair. Interestingly, our laboratory found GPR17 in thrombocytes. However, we do not know whether it has any function in thrombocyte aggregation or the nature of the ligand. In this paper, we studied the role of GPR17 in hemostasis, which is a fundamental defense mechanism in the event of injury. Using zebrafish as a model system, our laboratory has studied specifically thrombocytes, which play a significant role in hemostasis. The major reasons to use zebrafish as a model system are that their thrombocytes are functionally equivalent to human platelets, the adult fish are amenable to knockdown experiments, and they are readily available in the market. This study was performed by using a piggy back knockdown method where we used a chemical hybrid of control morpholino and an antisense oligonucleotide sequence leads to the degradation the mRNA for GPR17. After knockdown GPR17 in thrombocytes, the percent difference of the thrombocytes aggregation between the control and knockdown blood samples was measured by flow cytometry. We used various thrombocyte agonists to study differences in aggregation between the control and knockdown blood samples. The study showed that knockdown of GPR17 resulted in no significant differences in percent thrombocyte aggregation between control and agonist treated samples except for a slight increase in collagen-treated samples. Thus, it appears that GPR17 has no significant role in hemostasis.
Date: December 2015
Creator: Bohassan, Maruah Hejey
Partner: UNT Libraries