UBIR Repository (Univ. at Buffalo)
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Lecture Video Summarization by Detection and Representation of Content
No full textPh.D.Educational videos are an abundant resource thanks to the proliferation of Massively Online Open Courses and University Distance Learning programs. It has been shown that breaking down a lecture into topically coherent segments increases viewer engagement and that students tend to return multiple times to certain points in the video to review concepts. Thus, there is a need to \emph{summarize} the content so that a student can a) quickly decide which lecture to view and b) navigate to specific content. Information extraction from lecture videos is a challenging problem. Robust algorithms are required to handle illumination changes, occlusions due to speaker. Video annotation is expensive and time-consuming. Several lectures are self-recorded and do not have extensive production and transcript annotation and often involve a single fixed camera covering the content. Thus, there is a need for a pipeline to summarize lectures via visual text as opposed to text transcript. Further, content of lecture videos tends to be loosely structured consisting of phrases, math expressions, figures and graphics requiring specialized methods for processing as opposed to direct optical character recognition (OCR). In this thesis, we investigate methodologies and build frameworks to summarize both whiteboard and presentation-based lecture videos by detecting and representing \textit{visual content} in video frames. We define visual content as visible typeset and handwritten text, math expressions and sketches as opposed to spoken content. Lecture video summaries are commonly in the form of \textit{keyframes} - a subset of frames that contain all unique content within a corresponding segment of the video. Prior techniques typically use heuristic methods to estimate region of interest, binarize images and perform spatio-temporal analysis of binary connected component (BCC) content to summarize whiteboard videos. For presentation videos, most existing methods perform OCR on slide images to produce text-based summaries ignoring math and other content or use shot boundary detection to produce keyframes - this is susceptible to noise and unsuitable for text. As part of this thesis, we first developed a framework to directly detect \textit{regions} of various types of text content in whiteboard lecture videos by leveraging deep neural networks thus removing dependence on heuristic-driven methods for background removal. We then performed binarization, segmented the video and produced summary keyframes using spatio-temporal BCC analysis. Secondly, we investigated the use of deep triplet loss embedding to perform spatio-temporal analysis of content at the region level (as opposed to BCC) even with a lack of extensive annotations such as OCR transcripts. Inspired by recent advances in general video summarization, we also proposed summarization of lecture videos via \textit{key content} as opposed to keyframes. Finally, we develop a unified framework combining our preliminary work to detect and represent lecture video content, followed by spatio-temporal analysis at the region level to produce both keyframes and key content as summary. Region feature interactions are characterized to make accurate segmentation decisions that lead to compact summarization, retaining most of the unique content within the lecture. We obtained state-of-the-art results on public whiteboard lecture video data. We also demonstrate the generality of our framework by experimenting with presentation videos and show that the obtained summaries along with the data structures produced during spatio-temporal analysis allow us to navigate the video based on content regions and can be indexed for search and retrieval applications.**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.*
Humor in Shakespeare's Comedies, Histories and Tragedies from a Philosophical Perspective
No full textM.A.This thesis describes and analyzes the humor used in William Shakespeare's plays from a philosophical and psychological perspective. In doing so, this thesis demonstrates how humor constitutes meaning in Shakespeare's plays and at the same time traces the use of humor in the development of Shakespeare's craft. In order to set a context for this argument, this thesis introduces the various philosophical approaches to humor from Plato to John Morreall and Mikhail Bakhtin, appraising these critically and illustrating them with reference to Shakespeare's plays. This thesis then proceeds to consider individual Shakespeare's plays in the light of the most currently accepted philosophical and psychological approaches to humor. These plays include Twelfth Night, A Midsummer Night's Dream, Henry IV Part I, and Hamlet.**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.*
Rustbelt Radicals: Black Power in Buffalo and Rochester, New York in the 1960s-1980s
No full textPh.D."Rustbelt Radicals" examines the histories of two Black Power organizations in the Rustbelt, more specifically, in Western New York: BUILD (Build Unity, Independence, Leadership and Dignity) Buffalo, established in 1966 and FIGHT (Freedom, Integrity, God, Honor, Today) Rochester, established in 1964. BUILD and FIGHT were created before the Black Panther Party (BPP), and though they were influenced by national movements and organizations, they used local strategies to dismantle discrimination in urban renewal projects, created their own community-owned factories and campaigned against police brutality. This local focus led to many successful campaigns and programs, including FIGHT's attack on the Eastman Kodak Company's racially discriminatory hiring, the creation of the community owned and controlled factory FIGHTON, the establishment of the exclusively African American BUILD Academy, and the intervention and support of the Attica Brothers during the prison rebellion of 1971. BUILD and FIGHT sent powerful messages of Black solidarity to residents and took control of federal initiatives like urban renewal and the War on Poverty while coercing big businesses to heed to their demands to hire poor, urban African Americans. BUILD and FIGHT's local approaches were unique, yet their goals of promoting Black self-determination and pride were part of the broader Black Power movement. The stories of BUILD and FIGHT expand existing Black Power historiography, and answers historians' calls to study the more "obscure" organizations within this body of history. There are undoubtedly many more organizations like BUILD and FIGHT that have yet to be discovered; we must work to uncover their histories to understand the depth and complexity of the Black Power movement.**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.*
The Transcription Factor Ets1 Cooperates with IL-17 Receptor Subunit A to Prevent the Development of Autoimmunity and Immunodeficiency
No full textPh.D.Ets1 is a lineage-specific transcription factor that regulates B and T cell functions in development and disease. Mice that lack Ets1 (Ets1 KO) develop spontaneous autoimmune disease with high levels of autoantibodies. Naïve CD4+ T cells isolated from Ets1 KO mice differentiate more readily to Th17 cells and secrete IL-17, a cytokine extensively implicated in autoimmune disease pathogenesis, and the immune responses to bacterial and fungal pathogens. To determine if increased IL-17 production contributes to the development of autoimmunity in Ets1 KO mice, I generated Ets1 and IL-17 Receptor double knock out (DKO) mice. I used a combination of flow cytometry, ELISA, ELISPOT, immunofluorescence, and in vitro differentiation assays to evaluate immune responses in DKO and control mice. These studies demonstrated that the absence of IL-17 signaling did not prevent or ameliorate the phenotype of Ets1 KO mice, but rather that DKO animals exhibited worse symptoms with striking increases in the numbers of Th2, Th17, and Tfh cells. DKO mice also developed an increased number of germinal center B cells, isotype-switched B cells, memory B cells, and plasma cells. During my studies, I noted that DKO mice began to develop skin lesions as they age, typically on the ventral surface of the neck. These lesions harbored Staphylococcus aureus (S. aureus) bacteria, and S. aureus could be recovered from the skin of DKO mice, even before lesions developed. Using a bioluminescent strain of S. aureus and IVIS imaging, I found that DKO mice experimentally infected with S. aureus on the back skin were unable to clear the bacteria. Interestingly, older DKO mice (4-6 months of age) had a more significant defect in clearing S. aureus than did younger mice (2-3 months of age). This lack of clearance to S. aureus indicates that an age-related alteration in the immune response underlies the susceptibility. Because DKO mice have strong autoimmune responses, they accumulate autoantibodies as they age. I found that DKO mice produce autoantibodies against the antimicrobial peptides, including cathelicidin-related antimicrobial peptide (CRAMP) and β-defensin 1 (DEFB1). They also produce autoantibodies that bind to the cytoplasm of neutrophils. Because these innate immune system components are essential in controlling bacterial infections, I theorized that autoantibody-mediated neutralization of these components might underlie the susceptibility to S. aureus that develops with age. To further test the roles of one of the antimicrobial peptides in the immune to S. aureus, I infected CRAMP KO with S. aureus, but I found that these mice were equally capable of clearing the infection as WT mice. My current model is that excessive immune activation leads to the production of autoantibodies that accumulate with age and that target innate immune effector mechanisms important for anti-bacterial immunity, thereby resulting in susceptibility to skin infections with S. aureus. My studies may have important implications in understanding the mechanisms that drive pathogenesis in human diseases characterized by both autoimmunity and immunodeficiency.**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.*
A Theoretical Study of Adsorption Over the Ag/SSZ-13 Zeolite Informed with Experiments
No full textM.S.Zeolites are unique materials with exceptional adsorption properties exploited by various industries. One such industry application is the trapping of air pollutants emitted from a vehicle’s exhaust at low temperatures, before the catalytic converter activates at high, operating temperatures. Preventing the release of these "cold-start" emissions is expected to improve air quality. The trapping candidate material chosen for evaluation in this work is the zeolite SSZ-13 ion exchanged with Ag. Adsorption of ethylene (C2H4) and water (H2O), two components present in vehicle exhaust, where C2H4 is an undesirable emission is studied from density functional theory (DFT) calculations. The uncertainty stemming from approximations in DFT is propagated through adsorption models and results in adsorption behavior predictions holding uncertainties. The adsorption predictions and their uncertainties for three adsorption sites are reported and informed by experiments using Bayesian statistical framework. The three active sites studied are the intended Ag ion-exchanged with an H in the zeolite framework, an H site (known as a Brønsted acid site) and Ag2O which may form as a non-zeolite adsorption site during the Ag ion-exchange synthesis. Chapter 1 of this thesis is an investigation of co-adsorption of ethylene and water over the Ag ion adsorption site in the Ag/SSZ-13 zeolite using DFT calculations. The baseline Langmuir adsorption model and a microkinetic model including interactions between adsorbates are the two adsorption models that are explored in this study. Chapter 2 is a combination of theoretical and experimental work in which adsorption experiments were used to inform the modeled adsorption predictions for the three adsorption sites in Ag/SSZ-13, using Bayesian statistical framework.**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.*
Effects of Central α7 Nicotinic Acetylcholine Receptors on Energy Intake and Body Weight in Rats
No full textM.S.Obesity is a prevalent disease, but effective treatments remain limited. Agonists of the alpha-7 nicotinic acetylcholine receptor (α7nAChR) promote negative energy balance in mice, but these effects are not well-studied in rats. The α7nAChR agonist GTS-21 has been shown to increase the food intake-suppressive incretin hormone glucagon-like peptide-1 (GLP-1) in mice, suggesting that GTS-21 may produce hypophagia via a GLP-1-related mechanism. We tested the hypothesis that GTS-21 would decrease food intake and body weight in adult male Sprague Dawley rats. In a dose-response study of feeding and body weight change after acute intracerebroventricular (ICV) injection of GTS-21, contrary to our hypothesis, GTS-21 had no impact (p>0.05) on food intake and increased (p<0.05) body weight at the highest dose tested (0.5mg). As endogenous GLP-1 is rapidly degraded by dipeptidyl peptidase-IV (DPP-IV), we hypothesized that if GTS-21 induces GLP-1 release in rats, DPP-IV-mediated degradation of GLP-1 may mask feeding effects of GTS-21. We combined ICV administration of the DPP-IV inhibitor sitagliptin (SIT) with ICV GTS-21 and measured feeding effects when rats had a choice of both chow and palatable high-fat diet (HFD). Rats ate more chow with SIT, GTS-21, or SIT+GTS-21 at 1h post-injection (p<0.05), with no effect on HFD intake. Main effects of SIT and GTS-21 to increase chow intake were found at 3h. At 3h, SIT-treated rats also had lower preference for HFD than vehicle-treated rats. Finally, we hypothesized that a more selective agonist of the α7nAChR may produce stronger effects. ICV administration of the selective α7nAChR agonist PHA-543613 produced a numerical, but non-significant, decrease in body weight and intake of HFD, with no effect on chow intake. Collectively, our studies suggest a more selective agonist of the α7nAChR may be needed to produce a negative energy balance effect. Furthermore, lateral ventricle injection of SIT may induce a shift in food preference, favoring lower calorie food options.**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.*
Modeling a Multi level Intervention to Improve Oral Health for Chinese Americans
No full textPh.D.Many Chinese Americans experience certain barriers (e.g., low income, English as a second language, lack of insurance, cultural differences, discrimination) when they seek oral healthcare services. These barriers may contribute to health disparities by discouraging use (leading to reduced utilization) of preventive and treatment services. This dissertation research adopts a modeling approach to develop theory that accounts for dynamic relationships operating at multiple levels, from individuals to families to communities. A multi-method and multi-level modeling approach allows for the interaction of factors at different levels of aggregation. This research applies methods of spatial statistics and spatially explicit agent-based modeling to examine how demographic, socioeconomic, and geographic factors shape access to oral healthcare for low-income Chinese Americans in New York City. The simulation model developed in this dissertation was used to test different intervention scenarios involving community health workers who facilitate care coordination and other health promotion activities. In addition to demographic characteristics and socioeconomic factors, this study also considers geographic factors and spatial behavior, such as distance and activity space. The overarching contribution of this study is to provide a complex systems science framework to better understand access to oral healthcare for urban Chinese Americans, toward adapting it for other racial/ethnic minority groups, by integrating health-seeking behaviors at the individual level, barriers to care at multiple levels, and opportunities for health promotion at the community level.**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.*
Hidden Liquidity, Market Quality, and Order Submission Strategies
No full textPh.D.Traders in most equity markets can instruct exchanges whether they want to hide or display their limit orders on the book. While the ability to hide trading interests could be advantageous to liquidity providers, it increases uncertainties for liquidity demanders by reducing pre-trade transparency. Even though hidden liquidity accounts for approximately 20% of trading volume in the U.S., there is limited evidence on its effects. Exploiting a recent pilot program as an exogenous shock to hidden liquidity, we show that hidden liquidity has significant effects on various measures of market quality and order submission strategies after controlling for market volatility and other stock attributes. Hidden liquidity widens the quoted spread, as some traders switch to use hidden orders to minimize the probability of their orders being undercut by other traders. Other spread measures, depths, trading volume, and trade size increase with hidden liquidity. The extent of informed trading and the price impact of a trade also increase with hidden liquidity, suggesting that using hidden orders helps informed traders to take advantage of their private information more effectively. Traders use more inside-the-quote limit orders, consistent with informed traders' submitting less aggressive orders while uninformed traders trading more aggressively when there is more hidden liquidity. Algorithmic traders engage in more pinging activities and raise message traffic when there is more hidden liquidity to discover any trading interest that has not been displayed on the book.**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.*
Potential Power of Innovation: Perseverance, Openness and Students' Creative Problem-Solving
No full textM.A.Creative problem-solving (CPS) is referred to as a novel and innovative approach used in problem-solving situations, which focuses on divergently generating ideas, understanding the challenge, creating solutions and actively managing and examining the ideas at each stage. In accordance with the existing literature, the purpose of current research is to 1) investigate the relations between perseverance, openness and CPS, 2) explore whether there is a gender difference in the previous relations, and 3) discuss whether parent(s)' education level, occupation and students' Information and Communication Technology (ICT) use will have any association with students' CPS competency. Using the PISA 2012 data from Shanghai-China, descriptive statistics of included variables and linear multivariate regression analysis are conducted to analyze the results. My main findings include 1) Openness had a positive relation with CPS, and it was stronger comparing to the relation between perseverance and CPS; 2)The gender difference between openness and CPS was not significant, but the negative relation between perseverance and CPS was stronger for females; 3) Students whose parent(s) had higher level of education and/or occupation tend to have better CPS competency; 4) ICT use for different purpose had different relations with students CPS; 5) After controlling school-related factors (school types, school sectors and school mean socio-economic status (SES), there was no significant association between parental backgrounds and students' CPS competency.**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.*
Investigating the Integrated Performance Assessment (IPA) in University Classrooms
No full textPh.D.The Integrated Performance Assessment (IPA) is a task-based performance assessment designed to be used in language classrooms. The IPA framework is intended to combine this assessment with instruction for a seamless link between these two elements along with feedback. As the IPA's purpose is to serve as an assessment that corresponds with language use that is used for communication across the interpretive, interpersonal, and presentational modes and that reflects natural language use, this research investigates to the degree that it does so during the first three semesters of implementation. The study is a longitudinal, multi-semester study of the IPA in university-level communicative Spanish classrooms, and includes data and analysis from a pilot study that was conducted before the fuller study. Specifically, this study analyzes the effect of instructor feedback on student progress in the performance of oral and written communication across the three previously mentioned modes using both quantitative data from assessments and qualitative data from interviews, stimulated recalls, and classroom observations. The study investigates student task performance and how feedback effects this performance, forms of Spanish language that students use to complete the tasks, teacher and student attitudes about the IPA, how students incorporate the feedback to self-assess and set goals, and how teachers use the results to tailor their instruction or not. By the end of the third semester of implementation, students and instructors began to value the IPA as assessment to foster progress in the target language, but this was more on an individual level than as a program as a whole.**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.*