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Source Localization of Simulated Electroencephalogram of Virtual Epileptic Patient to Investigate Clinically Feasible Montages
No full textM.S.Source localization of electroencephalogram (EEG) data is commonly used to estimate regions of ictal onset in epilepsy patients with temporal lobe epilepsy. Results are used to inform further investigations and treatment options such as surgical resection. Localization of EEG data still struggles to achieve high spatial resolution, especially in deep regions of brain tissue, and is difficult to validate because the ground truth is unknown. In this paper we utilize a spatiotemporally realistic generative brain network model based on patient structural and functional data, created in The Virtual Brain (TVB) platform, to generate simulated EEG data for assessment of head model approaches, distributed source inverse methods and clinically feasible electrode montages. We find that dSPM is less sensitive to head model errors introduced when warping an anatomical template in localization; sparse montages with increased density over regions of interest provide a clinically feasible way to increase localization accuracy of a sparse montage; and TVB platform can be utilized to model patient anatomy and physiology virtually, incorporating individualized estimates of disease mechanisms through parameter choices reflecting clinical assessment, which may be implemented to determine an optimized electrode montage for the purpose of providing personalized neurological care.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Closing the Cage: Theorizing the Border and Permissibility of Violence at the Periphery
No full textPh.D.This work seeks to draw a thread through the academic approaches of conceptualizing space and time—through history and cartography—across their development and with an eye specifically towards their role in the formation of borders. It seeks to draw out the manner in which such structures of knowledge have come to be understood as precise or veritable representation of the world and are thus interchangeable with it. Simply put, this work takes borders as its object of analysis and, by working to isolate its development along fields of temporal (history) and spatial (cartography) knowledge, make tangible what remains elusive to analysis. Furthermore, it seeks to directly relate this ascension of knowledge with the formation of borders and, ultimately, with the violence that becomes increasingly permissible at the peripheries of the nation-state. Lastly, this work seeks to locate this analysis of knowledge squarely within the space of the Mexican-American border so as to better understand the manner in which these structures of knowledge play a role in an emerging crisis of human rights in the borderlands. It traces both the historical and cartographic developments of the borderlands to the culminating violence of the late 20th and early 21st centuries. Ultimately, it hints at the foundational paradox of the liberal nation-state that cannot sustain its ideologies in a borderless existence.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
"It Gives Me Courage to Do the Same": Exploring the Narrated and Lived Experiences of Refugee Students
No full textPh.D.This ethnographic case study explores refugee student perceptions of education, identity and experiences. It also aims to address the aspects of education that may hinder authentic learning, as well as modes of communication and instruction that are beneficial for refugee student learning. Through the data collection of interviews, artifacts, and observations, this study aims to provide new perspectives on refugee student education, with Culturally Relevant Education as an overarching theoretical concept. This research is undertaken in the effort to showcase the impact of student voices, specifically those of refugee students who are often underrepresented. Findings reflect student interest in social justice and reform, as well as the role of multimodal learning in addressing issues of language, cultural biases, and the pressures of a high stakes testing culture.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Graphene Oxide Modified Membranes with Enhanced Antifouling Properties for Microalgae Dewatering
No full textM.S.Ultrafiltration (UF) membranes are attractive for microalgae dewatering due to the high energy-efficiency. However, the membranes can be fouled by the organic matters in the microalgae solutions, resulting in low water permeance. Enhancing the hydrophilicity of the membrane surface is a practical approach to mitigate fouling by decreasing the adhesion between the membranes and foulants. In this work, we graft graphene oxide (GO) onto the UF membrane surface using bio-adhesive polydopamine (PDA). The GO is rich with COOH groups, which react with the amine groups of the PDA. The effect of the GO coating on the microalgae dewatering performance is evaluated using microalgae solutions of various concentrations. The GO modified membranes show less microalgae adhesion and higher water permeance than the unmodified membranes.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Alcohol-Directed Behavior under Intermittent Access and Nicotine
No full textPh.D.One of the primary goals of addiction research is to better understand the behavioral and mechanistic processes underlying drug-directed behavior. In particular, patterns of drug-taking behavior are important in determining changes in both intake and drug-directed motivation. For example, intermittent-access schedules of cocaine reinforcement in rats result in a pattern of spiking brain drug concentrations, and lead to enhanced motivation for the drug, compared to continuous access schedules in which drug is freely available (Zimmer et al. 2012). Preclinical models of alcohol and tobacco use disorders would benefit from examining how patterns of drug-taking can influence drug-directed motivation and intake. The present experiments sought to address this by examining how different patterns of alcohol self-administration in the presence of absence of nicotine can alter intake and motivation for alcohol; Specifically, 1) whether within-session intermittent access to alcohol would alter alcohol-directed motivation and intake relative to continuous-access subjects (experiment 1), and 2) whether pattern of nicotine and alcohol self-administration could change drug-directed behavior by examining the self-administration of both either continuously (experiment 2), or intermittently (experiment 3). The results show 1) that intermittent-access alcohol produced a similar pattern of intake to long-access, 2) did not affect motivation to work for alcohol under progressive ratio and extinction conditions, but 3) alcohol-directed motivation was not related to intake across subjects. Further, 4) when nicotine and alcohol were taken continuously together, and 5) when nicotine and alcohol were taken in intermittent alternation, the presence of nicotine appears to suppress alcohol intake without affecting responding for alcohol. These results indicate factors regulating alcohol intake are separable from operant behavior, and intake specifically is acutely suppressed by nicotine when it is present during bouts of alcohol drinking.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
mmWave Radar Based Real-Time Human Pose Construction
No full textM.S.Recently, Millimeter wave(mmWave) FMCW radar sensors are popular in diverse application scenarios of Internet of things (IoT), especially in industrial and automobile scenarios. This type of sensors have specialty of providing the range, velocity, and angle of detected objects which may block by some materials in the line of sight, which makes they outperforms camera in some special scenarios. However, applying mmWave radar sensor on the human pose reconstruction task still lacks extensive research. So, this paper presents a real-time system based on TI automotive mmWave radar sensors that can estimate 3D pose of the human body from streaming Analog-to-Digital Converters (ADC) signal data. This system can capture ADC signal from TI AWR1843 radar sensor coupled with DCA1000 and convert it to points cloud array with classical radar signal processing algorithms. Then, points cloud will be fed into a deep learning model which extracts pose parameters of detected human body and constructs and renders the human pose in 3D skeleton form. The system performance achieves real-time level reconstruction of the 3D human pose within centimeter-level error and 300ms delay at 10fps.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Understanding the Effects of Obfuscation on String Analysis for Malware Classification
No full textPh.D.A high quality malware detection tool must utilize a feature set that provides high classification accuracy but is also difficult for malware developers to mask with obfuscation. We propose that the use of string structures provides this type of feature as it can classify malicious code with high accuracy even in the presence of obfuscation. Obfuscation itself provides malware developers tools and techniques to hide malicious intent. This significantly degrades the ability of many malware detection tools to accurately classify malware as occurrences of malicious intent used as classification features are no longer present or purposefully misrepresented. String structures capture how strings are created and employed by mobile applications and are themselves resilient to different forms of obfuscation. This is because string structures are not focused on the literal content of the string and are focused instead on the set of operations needed to create the string which is more difficult to meaningfully obfuscate. We provide an analysis of multiple obfuscation tools, both academic and open source, and examine how different types of applied obfuscation change an application's code structure. Our research shows that these changes do not significantly affect string structures nor the most important features from this set used for malware classification. Our research furthers the field of malware analysis in two ways. First, it provides string computations as a new, obfuscation resilient feature for classification of malware and benign applications. This feature type can be used either independently or as a complement to other feature types for more accurate classification of malware. Second, it provides a set of metrics that may be used to measure obfuscation resiliency in terms of the feature set used for classification. Currently, obfuscation resiliency is tied to accuracy measures for obfuscated applications but ignores how the underlying feature set changes and its implications. Our metrics allow this change to be measured and compared across different obfuscation tools and their obfuscators.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Perovskite Based Catalysts for Dry Reforming of Methane
No full textM.S.More than ever, the need for dry reforming has been increasing in the past few years because of its ability to convert the most signficant greenhouse gases (methane and carbon dioxide) into syngas (carbon monoxide and hydrogen) which further can be used to synthesize various other compounds by Fischer-Tropsch synthesis or other downstream processing. In this thesis, we have chosen perovskites as a route to catalysts for dry reforming of methane. With various applications in the chemical world, perovskites can also generate good catalysts for dry reforming because of their ability to disperse the active metal uniformly over the support, by initially incorporating the active metal into the perovskite phase. The LaNiO3 perovskite was synthesized using the Pechini method of sol-gel synthesis and analyzed by complementary material characterization techniques including X-ray diffraction, Brunauer–Emmett–Teller method for surface area analysis, Scanning Electron Microscopy and Transmission Electron Microscopy. To determine whether the perovkite route to catalyst production improves catalyst performance, catalysts were also synthesized in the gas phase (aerosol route) with the same support to catalyst ratio, but without forming the perovskite phase. The High Temperature Reducing Jet Reactor (HTRJ), a novel flame-based aerosol process for nanomaterial production, was used to make these aerosol synthesized catalysts. Both catalysts were tested for their methane dry reforming activity at 500oC to 800oC. Both catalysts were very active because of the high nickel percentage in the catalyst (30%), but the HTRJ catalyst coked earlier and was less stable. The perovskite-derived sample was then promoted using other basic metals by replacing half the nickel concentration in an attempt to improve stability and performance. The best performance was obtained from catalysts containing Mg and Sr. They were compared to their gas phase-synthesized counterparts which coked earlier than the last time, because the nickel available was halved and as soon as the active nickel particles were covered with carbon nanotubes, there was no more conversion. This was also evident from reduced flow rates leaving the reactor and high pressure inside the reactor. Stability tests were performed for the perovskite-derived Mg and Sr samples for 12 hrs at 800oC. Both samples showed evidence of significant coking, but did not lose activity during this 12 hour test, and proved much more stable than the aerosol-synthesized catalysts. The Sr sample gave lower conversion but also showed less coking. Based on the results, future research directions for perovskite-derived catalysts are suggested.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Central solTNF in the Mechanism of Neuropathic Pain
No full textM.A.Chronic pain will affect >50 million U.S. adults in 2020. Defined as pain persisting longer than six months, chronic pain is a leading reason why adults seek medical care. Neuropathic pain is a type of chronic pain linked to damaged nerve fibers, which then incorrectly communicate with the body’s pain centers in the spinal cord and brain. Tumor Necrosis Factor (TNF) is a pro-inflammatory cytokine that when produced in excess is involved in neuropathic pain. TNF exists in two forms, soluble (solTNF) and transmembrane TNF (tmTNF). This study tested whether analgesia produced by blockade of brain TNF entails selective inactivation of solTNF or requires inhibition of both forms. Prior research suggests that selective inhibition of solTNF offers better treatment for chronic inflammation than non-specific, antibody-mediated TNF blockage. We hypothesized that analgesia produced by TNF-antibody blockade of brain TNF is mediated by inactivation of solTNF that primarily activates pro-inflammatory TNF receptor 1 (TNFR1), as opposed to TNFR2. Neuropathic pain was induced in male and female Sprague-Dawley rats via chronic constriction injury (CCI); control rats received sham surgery. Withdrawal latencies to a noxious thermal stimulus (hyperalgesia) and withdrawal to innocuous forces (allodynia) were recorded every other day for 8 days and compared to baseline values and to sham-operated rats. On day 4 following pain behavior testing, rats were randomized to receive a perispinal injection (100 µl) of saline (vehicle), anti-TNF antibody (3 µg), control IgG isotype antibody (3 µg), or the selective solTNF inhibitor INB03 (3 μg). In addition to sensory nociception testing (thermal hyperalgesia and mechanical allodynia), cognitive testing (novel object recognition) for memory, which is negatively impacted during chronic pain, was performed. To determine the TNFR-mediated pathway involved in neuropathic pain, we (i) completed western blot analysis of ex vivo brain specimens from the locus coeruleus, left hippocampus, mid prefrontal cortex and parietal cortex, and (ii) quantified secondary messengers including ASK1 (TNFR1), NF-κB (TNFR2), and TGFβ-3/-1 (tmTNF reverse signaling). Preliminary results from western blot analysis of left hippocampus and locus coeruleus brain regions showed CCI-induced increase in ASK-1 and NFκB-p65 levels that were reduced by perispinal TNF-Ab.CCI-induced thermal hyperalgesia was completely relieved in male rats following PS TNF-Ab, but only transiently relieved by INB03. Female CCI rats also demonstrated decreased thermal hyperalgesia following blockade of brain TNF, although to a lesser extent than males. For male rats tactile allodynia (1-G stimulus) was unaffected by PS TNF-Ab, while mechanical allodynia (15-G filament) was significantly reduced (at day-8 post-CCI) by PS TNF-Ab. For Female rats treated with PS TNF-Ab, tactile allodynia (1-G stimulus) appeared to be reduced, but this did not seem to be the case for the 15-G filament (at day-8 post-CCI). CCI-induced cognitive impairment did not show any conclusive results. Therefore, blocking brain TNF via PS administration of TNF-Ab is anti-nociceptive for CCI-induced neuropathic pain.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Women and the Consolidation Controversy: The Development of the American Catholic Church, 1800-1870
No full textPh.D.This dissertation bridges the fields of Catholic History, Women's History, and American Religious History to propose a new perspective for studying the development of the American Catholic Church, termed by me as the Consolidation Controversy. Previous historians have focused on the development of the local parishes and the diocese, focusing on the power conflicts between the lay trustees and the local bishops that accompanied this institutional growth. However, an often-forgotten aspect of Catholic history is the simultaneous rise of religious congregations and orders. As these communities developed, their leaders clashed with the local bishops over questions of property and authority over members of the communities. Often at the center of these power struggles were the women religious. Rather than allowing themselves to be manipulated, women religious demonstrated their own agency, navigating larger institutional politics. Should these women fail to maneuver these institutional relationships, they faced losing their autonomy within the diocese as well as their position and vocation as women religious. This dissertation examines three religious communities in America, each of whom endured the politics of Catholic Consolidation. The first is the Oblates of Providence, the first congregation for women religious of African-descent. The Oblates could be called an "ideal" Catholic model of diocesan governance under the leadership of the bishop and other local clergy. The second case study is the Order of the Preachers of St. Dominic, or the Dominicans, who employed a provincial style of governance. The Dominican Order consisted of friars and nuns both, leading to multiple struggles over authority and jurisdiction in the local dioceses. The final case study, the Sisters of St. Joseph, were also a provincial-style congregation. However, they promoted female leadership, questionably undermining the authority of the local bishops. Each of the three case studies point to a distinct trend in consolidation, as these various congregations either supported the authority of the local diocesan bishops or argued for the autonomy of their communities. The resulting power struggles, and the role women played within them, created the Consolidation Controversy.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*