22484 research outputs found
Sort by
Marvels and ‘Aja’ib as Contact Points: Medieval Christian, Muslim, and Jewish Literature on Cultural Contact
No full textMedieval people were fascinated by marvels, or those things, beings, or phenomena that are primarily natural and yet unexplained. Medievalists studying western Europe have used those things classified as marvels to interrogate medieval views of power, theories of mind, and the natural world. Scholars of the Islamicate world have considered ‘ajā’ib (“marvel” in Arabic) literature through the lens of Islamic belief, philosophical debates, and reception of classical thought. Scholars of both traditions have discussed the ways marvels appear in travel literature and act to demarcate the known from the unknown. This dissertation engages with the existing scholarship on marvels and ‘ajā’ib from the perspective of the Global Middle Ages, considering how movements of people, ideas, and trade goods shaped participating cultures in profound and unexpected ways. Through four case studies, this dissertation, “Marvels and ‘Aja’ib as Contact Points: Medieval Christian, Muslim, and Jewish Literature on Cultural Contact,” argues that the marvel often functions as a figure for cultural contact in medieval writing; and by interpreting the marvel, we can better understand the text’s position regarding who or what is considered foreign. Chapter one traces the intellectual trajectory of medical theories of human generation as they reached England and found expression as a monstrous birth in the climax of the fourteenth-century romance The King of Tars. Chapter two offers a comparative reading of the vita of Christina the Astonishing and an Ashkenazic Jewish exemplum from Sefer ha-ma’asim that present as marvels embodied dead women as commentaries on proper piety. Chapter three studies the way self-described scholar and reformed charlatan al-Jawbarī’s exposé of con artists, Kash al-asrār and Geoffrey Chaucer’s Canon’s Yeoman’s Tale employ similar rhetoric to argue against alchemy’s categorization as a marvel. Chapter four traces the adaptations made to the story of the mystical and marvelous City of Brass and its connection to the popular Alexander Romance cycle, as the economy of the Islamicate world incorporated sub-Saharan Africa. Taken together, the chapters of this dissertation offer a taxonomy of the medieval marvel in its role as a vessel holding the attitudes, anxieties, and hope involved in cultural contact
Logic, Arithmetic, and Definitions
No full textArithmetic and logic seem to enjoy an especially close relationship. Frege once wrote that arithmetic is reason’s nearest kin. To deny any of the basic laws of arithmetic seems tantamount to denying a basic law of logic. My dissertation is concerned with two great attempts to make something more of this informal idea. In one direction, Frege tried to reduce arithmetic to nothing but quantificational logic and definitions. Neo-logicists continue to follow in Frege’s footsteps, pursuing a version of this program today. In the other direction, Gödel tried to reduce certain applications of quantificational logic to nothing but arithmetic and definitions, by means of his Dialectica translation.
In the first half of my dissertation, I prove new theorems (with Jeremy Avigad) that shed a surprising light on the prospects for neo-logicism. An important objection against neo-logicism is that it makes use of allegedly stipulative definitions that are not conservative over pure logic, i.e., definitions that settle open questions that we could not have settled before. This violates a basic requirement on stipulative definitions. I argue that by passing to a richer logical and definitional framework, it is possible to overcome the conservativeness objection. However, there is a subtlety: the strategy succeeds only if conservativeness is understood semantically rather than deductively. This suggests that the viability of neo-logicism is highly sensitive to the way in which epistemic commitments are represented in formal theories.
In the second half of my dissertation, I argue that Gödel’s Dialectica translation succeeds in assigning a constructive meaning to quantificational theories of arithmetic. Virtually all commentators have objected that Gödel’s translation makes use of definitions which presuppose the very quantificational logic that Gödel was trying to eliminate. This, of course, would render the translation philosophically circular. Gödel was adamant that there was no circularity here, but no one has been able to understand his defense of this claim. I vindicate Gödel, showing that there is no circularity and answering a longstanding exegetical question in Gödel scholarship
Exploring the Use of Course Design to Support the Student Experience in an Asynchronous, Online Curriculum
No full textThe globally shared pandemic experience forced schools to shut their doors and required communities to examine their education systems. An important part of that examination is the evaluation of online learning education options. Online K-12 learning continues to grow, so examining how it can work better for students is important. This dissertation in practice study examined the use of a nationally recognized online course rubric to improve the student experience on an asynchronous, online platform through a series of three inquiry cycles: evaluating an existing course, revising units of the existing course, and implementation of the revised units with students. The outcome of this study was a revised evaluation rubric consisting of a unit-level and course-level section to support the organization within their course development, evaluation, and updates. The revised rubric tailors the national rubric to the specific needs of a local educational service center that provides online learning
Philosophical Foundations of Resource Rational Analysis
No full textTacit appeals to systems being rational or apparently irrational are common in cognitive science, and for good reason: irrationality provides valuable evidence for cognitive models. A methodological approach in cognitive science called resource rational analysis attempts to systematize the use of irrationality to develop and test models of cognition. It does so by initially assuming that a system is rational, and then iteratively de-idealizing this assumption by identifying psychological facts that prevent a system from being more rational. This dissertation seeks to analyze how this strategy has worked, how it should work, why it will work, and why it can work better with the conceptual foundations proposed here. In Chapter 1, I develop a specific account of resource rationality. I argue that all epistemic norms are relative to cognitive constraints, and that there is no principled way to distinguish between agents doing their best relative to their limitations and agents being irrational. I advocate for a maximally broad view of cognitive constraints, which renders all agents trivially resource rational, but still allows for meaningful evaluation and prescription. Chapter 2 reviews arguments that intentionality presupposes rationality, and argues that this position is strengthened if the appropriate notion of rationality is understood as my notion of resource rationality. This conclusion shows why rationality considerations are important and even necessary for any intentional psychological science. In Chapter 3, I extend my account of resource rationality to normative commitments, proposing that what I call a meta-reflective capacity—maintaining resource rationality under varying conditions—is necessary and sufficient for possessing normative commitments. This perspective offers a framework for endowing AI systems with normative commitments and empirically investigating these commitments in humans and non-human animals. Chapter 4 presents resource rational analysis as a methodological strategy in cognitive science and argues for its effectiveness. This strategy, I show, implements a dynamic theory-testing method known as ``Closing-the-Loop," as described by Smith (2014). I use the Material Theory of Induction and Topological Learning Theory to provide an epistemic justification for this dynamic testing strategy. These considerations support the iterative de-idealization process and demonstrate the utility of rationality considerations in cognitive science
Cell Type-specific effects of Liver X Receptor (LXR) and Estrogen Sulfotransferase (EST) on T-cell Mediated Autoimmune Hepatitis (AIH)
No full textAIH is a chronic liver disease in which the immune system attacks the liver cells, causing inflammation and liver damage. Long-term and uncontrolled AIH leads to progressive liver fibrosis and cirrhosis. However, the pathological mechanism of AIH remains elusive and there are no effective therapies except for the use of nonspecific immunosuppressive agents such as glucocorticoids. Liver X receptors (LXR), including the α and β isoforms, are nuclear receptors with pivotal roles in the transcriptional control of lipid metabolism. LXRs are previously known for their controversial effects on the development of immune-related diseases, but the specific role of LXRs in the pathogenesis of AIH has not been sufficiently explored. Estrogen sulfotransferase (EST or SULT1E1), a target gene of LXRs, is a phase II conjugating enzyme that catalyzes the transformation of an unconjugated estrogen into a sulfated estrogen, which makes estrogen inactive. Previous work from our lab demonstrated that Est is inducible and functional in several inflammation diseases, including liver ischemia and reperfusion (I/R) injury, sepsis-induced inflammatory response, hemorrhagic shock-induced lung injury, and I/R-induced acute kidney injury. However, the possible mechanisms and roles of EST in AIH remain unknown. In this dissertation study, I studied the cell type-specific effects of LXRs and EST on Concanavalin A-induced mouse AIH model. My results demonstrated that (1) Activation of LXRα sensitizes mice to ConA-induced AIH in iNKT cells and IFN-γ dependent manner. Pharmacological inhibition of LXRα may represent an effective approach to manage AIH in the clinic. (2) Hepatocyte Est is required for the sensitivity of female mice to ConA-induced AIH in an estrogen-independent manner. Mechanistically, Est ablation may have protected female mice from ConA-induced AIH by upregulating lipocalin 2 (Lcn2). Pharmacological inhibition of Est might be a potential strategy for the treatment of AIH. In summary, my dissertation research has uncovered the cell type-specific effects of LXRs and EST in AIH
MRTF-dependent Paracrine Regulation of Osteoclast Differentiation and Bone Colonization of Breast Cancer Cells
No full textBone is a frequent site for breast cancer metastasis. Conditioning of the local tumor microenvironment through crosstalk between tumor cells and bone resident cells in the metastatic niche is a major driving force for bone colonization of cancer cells. The vast majority of breast cancer-associated metastasis is osteolytic in nature due to dysregulated action of osteoclasts (OCL). Osteoclastogenesis and OCL survival are greatly enhanced by increased secreted levels of RANKL and other soluble factors contributed by tumor cells, osteocytes, osteoblasts, and immune cells. Increased bone resorption promotes the release and activation of ECM-bound growth factors and cytokines, further amplifying this loop and stimulating tumor cell proliferation and metastatic colonization of tumor cells. The present study investigates the role of Myocardin-related transcription factor (MRTF - a major cofactor for the transcription factor serum-response factor, SRF) in tumor-cell directed paracrine modulation of OCL differentiation and metastatic colonization of breast cancer cells. We herein demonstrate that MRTF depletion in breast cancer cells severely impairs experimental bone colonization of breast cancer cells in vivo. We further show that MRTF plays a key role in tumor-cell directed paracrine modulation of RANKL-induced OCL differentiation of bone marrow-derived macrophages (BMDMs). Luminex and transcriptomic analyses revealed that MRTF depletion in breast cancer cells impacts a broad range of cell secreted osteoclast regulatory factors. Rescue experiments demonstrated that downregulation of pro-osteoclastogenic matricellular protein connective tissue growth factor (CTGF) partly underlie the repressive effect of MRTF-depletion in breast cancer cells on RANKL-induced OCL differentiation of BMDMs. SRF’s interaction is critical for MRTF-dependent regulation of CTGF. A strong positive correlation between CTGF expression and MRTF gene signature in human breast cancer further establishes the clinical relevance of our findings. In conclusion, this study uncovers a novel functional aspect of MRTF in bone colonization of cancer cells, and we propose that MRTF inhibition could be a novel strategy to suppress OCL activity and skeletal involvement in metastatic breast cancer
Political-Economic Polarization
No full textThe political landscape in post-industrial democracies is increasingly turbulent and polarized, driven by structural economic changes, especially production automation since the mid-1990s. This dissertation explores how economic polarization (a disappearing middle class) fuels political polarization (declining moderate parties, candidates, and voters). It introduces the concept of “political-economic polarization" to explain the interplay between economic change and party system shifts. This theory provides insights into the political economy of job automation, examining its impact on political attitudes, partisan politics, and the interplay of economic, cultural, and institutional factors, drawing on political economy, institutions, party politics, and political psychology.
Structural economic changes create vulnerabilities among workers that political parties exploit strategically. Whether a party can appeal to these workers depends on its status as part of the establishment or an outsider and is critically dependent on a country's electoral institutions and party systems, which shape the mechanisms sustaining political polarization. In majoritarian systems, right-wing populists focus on tax and transfer policies to win the support of at-risk workers in marginal districts. In proportional representation systems with trichotomous multipartism (PRITM), right-wing populists emphasize identity-related issues rather than material transfers to attract dissatisfied voters. On the demand side of political representation, this dissertation proposes two channels explaining why at-risk workers shift to radical right instead of left parties and candidates. First, at-risk workers experience increased cultural grievances, including feelings of marginalization and nostalgia. Second, declining political efficacy among workers leads to political alienation, paving the way for radicalization. This work employs a multi-method approach, integrating formal modeling, time-series cross-sectional analysis, panel data analysis, survey experiments, and text-analysis techniques.
Despite the overall increase in political polarization, the strategies of outsider parties and leaders to mobilize support vary significantly. This research is among the first to consider how political-institutional contexts moderate economic polarization's effects on elections. It also explains why at-risk workers turn to right-wing populism. Methodologically, it advances political communication studies by utilizing cutting-edge natural language processing techniques to measure populism and identify issues. On the demand side, it employs a survey experiment with double randomization to identify causal mechanisms between automation exposure and politics
Bolstering the Immune System for Improved Defense Against Klebsiella pneumoniae
No full textKlebsiella pneumoniae (KP) are gram-negative bacteria of public health concern due to their capacity to acquire antibiotic resistance and cause deadly infections. Macrophages are crucial in the host defense against KP and understanding factors causing cellular dysfunction during severe infection is a priority. Signal transducer and activator of transcription 1 (STAT1) is a mammalian master transcription factor crucial for immune cells function. STAT1 is activated through interferon (IFN) signaling and helps defend against systemic spread of acute KP-intrapulmonary infection.
We found that in a two-hit model of an acute rise in red blood cell (RBC) engulfment by macrophages and KP-intrapulmonary infection caused dysregulated STAT1 suppression, both in vitro and in vivo. Using a mouse pneumonia model, we found that STAT1 deficiency led to an early neutrophil-dominant transcriptional profile and recruitment in the lung, followed by KP dissemination and lung injury. However, myeloid-cell STAT1 was dispensable for widespread KP control. By single cell RNA seq, KP-infected lungs of Stat1-/- mice displayed heightened CD4+T-cells at 24h and further analysis showed IL-17-producing CD4+T-cells were increased in lungs of Stat1-/- mice. Blocking global IL17-signaling led to increased KP proliferation and dissemination, while CD4+T-cell depletion reduced KP in lungs of Stat1-/- mice. These findings suggest STAT1 employs myeloid cell-extrinsic mechanisms to regulate neutrophil responses and protect against invasive KP by restricting non-specific CD4+T-cell activation in the lung.
Furthermore, we speculated that both host and pathogen factors were associated with the overall STAT1 protein degradation observed in the two-hit model of excess heme from RBC engulfment in macrophages and KP-infection. We found that STAT1 was not completely degraded through the proteasomal pathway upon KP+Hemin stimulus. Surprisingly, p62 expression, an important component of autophagy machinery formation for lysosomal degradation, was induced upon macrophage stimulation with KP, but hemin failed to suppress p62, while IRF1 (a downstream effector of STAT1) remained suppressed. Moreover, we noted variability of STAT1 protein expression in macrophages upon excess hemin challenge with different KP capsule-type strains. Overall, these findings suggest STAT1’s degradation through alternative mechanisms during oxidative stress from exposure to KP+Hemin along with the complex regulation of STAT1 during KP-infection
The Journey Through Focused Exploration: Engaging Sophomore TRIO Student Support Services Scholars
No full textEven though the sophomore year in college is a pivotal time when students make important decisions impacting their college experiences, the provision of a structured sophomore-year program has not been a priority in higher education in the United States. For the first-generation, low-income students participating in TRIO Student Support Services (TRIO SSS) who face additional obstacles throughout their college journey, the “sophomore slump” has even more potential of leading to lower levels of academic achievement and higher levels of attrition. As a Director of TRIO SSS, I aim to increase the number and self-efficacy of sophomore participants utilizing TRIO SSS services by 50% as evidenced by (a) the students’ increased sense of belonging within the SSS community, (b) the movement of participants from the state of focused exploration to tentative choices, and (c) the students’ increased engagement in both TRIO SSS and campuswide opportunities.
For this inquiry, I developed a series of events called the SSS Sophomore STRATEGY Series that addressed specific needs of sophomore-level students. The improvement science approach consisted of a mixed-methods research design with a participant survey seeking to gather quantitative data and focus groups gathering qualitative data exploring perceptions of how the Series impacted participants’ sense of belonging, their motivation to engage with TRIO SSS and campus events, and their creation of a personalized success strategy.
The key findings indicated that the Sophomore STRATEGY Sessions increased second-year participants’ sense of belonging, assisted them in crafting a personalized success strategy, and motivated them to engage actively with other events and activities organized by the TRIO SSS program. Moreover, the findings demonstrate the compelling interrelationship between sense of belonging, engagement, and a successful journey through focused exploration for sophomore college students, particularly those from first-generation, low-income, and other underrecognized backgrounds
Situationally Tailored and Analyzable Traffic Signal Control in Multimodal Networks
No full textThe increasing complexity of urban transportation systems requires innovative approaches in traffic signal control to enhance mobility, safety, and efficiency. This dissertation presents a comprehensive study of current practices, challenges, and potential advancements in traffic signal management through situationally tailored and analyzable traffic signal control solutions. Key objectives include conducting a detailed survey of traffic signal professionals, developing analyzable signal control strategies, establishing a methodology for programming an Event-Based Control (EBC) using DUMKA_E, benchmarking and demonstrating advanced functionalities of EBC, and implementing customized signal control strategies to improve multimodal urban traffic operations.
A comprehensive survey was conducted among professionals across North America to explore methodologies, challenges, and practices in multimodal signal retiming projects. The survey revealed a reliance on various tools and extensive data collection, highlighting the complexities of accommodating diverse traffic needs and balancing roadway user priorities.
This research introduced the EBC framework, implemented in the DUMKA_E virtual controller, to tackle these complexities. EBC provides greater programming flexibility than traditional control systems, allowing professionals to develop customized control logics suited to specific conditions, especially for multimodal users. Benchmarking EBC in microsimulation against commonly used controllers validates its effectiveness and demonstrates its advanced capabilities in developing more efficient control logics.
This study proposed the concept of “analyzable solutions” that practitioners can easily assess, contrasting them with solutions derived from opaque optimization tools. This approach was used to address traffic congestion on closely spaced, separately coordinated arterials impacted by shared left-turn lanes within one-way couplets during peak hours. The proposed analyzable signal timing strategies, Lagging Pedestrian phasing, Left-Turn Progression offsets, and Multicycle Co-Coordination-Based Gating, demonstrated significant improvements in queue lengths, delay, travel time, and environmental impacts.
This research bridges gaps in existing traffic signal control methodologies, offering innovative solutions to enhance multimodal urban traffic management. The proposed strategies promise to improve efficiency, safety, and sustainability in urban mobility, paving the way for more responsive and adaptable traffic signal control systems. Future research directions include customizing analyzable solutions for different transportation modes, integrating with public transit and micro-mobility, and developing dynamic pedestrian control strategies utilizing the EBC concept