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Essays in Sequential Games
No full textIn my dissertation, I explore the intricate dynamics of decision-making in three distinct contexts: protest participation, sequential games, and delegation problems. Firstly, I develop a framework to understand why individuals engage in protests despite the costs of participation, minimal individual impact, and non-exclusive benefits. This model incorporates stochastic opportunities for participation, which determine whose decisions are crucial to the protest's success. Secondly, I introduce the concept of simplification games to address the inherent human preference for simplicity over optimal strategies in sequential games. This new game type considers players' preferences for both outcomes and strategy complexity, providing a basis for rationalizing empirical mistakes. Finally, in collaboration with a coauthor, I examine a delegation problem in which an agent holds private knowledge about the suitability of a multidimensional action. We investigate the range of outcomes the principal can achieve when there exists one dimension where their ideal actions significantly diverge. We show that there exists a mechanism through which the implemented action in the dimension with pronounced disagreement increasingly aligns with the principal's ideal uninformed action as the extent of disagreement intensifies. In every other dimension, the principal's payoff nears the level she would attain if she had access to all the information pertinent to her actions in those dimensions
Influences of Negation on the Predictability and Informativity of Sentence Continuations
No full textThis study investigates how negation influences expectations for upcoming words in sentences, examining the interplay between negation, semantic constraints, and informativity. Experiments 1 and 2 extended Albu et al.'s (2024) findings by using a regular cloze task to explore how negation and modal adverbials affect sentence completions. Results showed negative sentences yielded completions with lower semantic relatedness, higher entropy, and lower cloze probabilities compared to affirmative conditions, with modal adverbials further reducing informativity and semantic constraint. These findings suggest negation serves multiple functions, including describing negative events and denying plausible ones. Building on these results, Experiments 3 and 4 focused on comprehenders' expectations about speaker informativity with negation. Experiment 3 employed a two-choice cloze task, while Experiment 4 used a regular cloze task. Results revealed a preference for negating antonyms, preserving the meaning of affirmative counterparts, indicating a tendency to use negation for describing events rather than solely for deviating from expectations. The study highlights negation's complex, context-dependent role in language processing and production. Future research directions include investigating shared knowledge among interlocutors, exploring interactions between pragmatic markers and negation, and conducting corpus analyses to complement these experimental findings
Batch-to-Continuous Transition in Specialty Chemicals Industry: Intensified Dispersants Production
No full textThe specialty chemicals industry relies heavily on batch reactor technology due to its
operational simplicity and versatility in handling diverse chemistries. However, batch reactors face
significant challenges in large-volume production, including heat and mass transfer limitations
which result in poor operational efficiency, and safety concerns when processing large volumes of
hazardous chemicals. Transitioning to modular continuous processing units holds the potential for
addressing these challenges, as demonstrated in our previous study of succinimide dispersants
production.
The first part of the dissertation aims at back-integrating succinimide dispersant production
by transitioning the production of a key reactant, polyisobutenyl succinic anhydride (PIBSA), from
batch to continuous operation and thus unlocking the full benefits of continuous operation for the
overall process. PIBSA is produced via reaction of polyisobutylene (PIB) with maleic acid
anhydride (MAA) and poses significant challenges for continuous processing, including slow
intrinsic kinetics and hence long batch times at typical operating conditions, poor miscibility
between reactants that result in strong mass transport limitations, and solid byproducts formation
due to the high reactivity and thermal instability of MAA. We address these issues by (i)
demonstrating novel ways for mitigating MAA side reactions via enhanced reactor mixing, and
(b) acquiring the first robust reaction kinetics for PIBSA formation, which are then used to model
different reactor operation schemes to identify suitable operating conditions for continuous
processing. Overall, this work supports the transition from batch to continuous processing for
v
PIBSA production via a recycle reactor operation, aimed at integrating succinimide dispersant
production into a fully continuous process, thereby improving operational efficiency and
scalability.
The second part of this dissertation briefly evaluates a hydrodynamic cavitation reactor as
a novel reactor concept for succinimide dispersants production by investigating its heating, mixing,
and reactive performance. Counter to expectations, however, our findings indicate that cavitation
phenomena offer little to no additional intensification potential over conventional tubular reactor
operations.
In summary, this dissertation elucidates the methodology for transitioning from batch to
continuous processing in the specialty chemicals sector
Role of lactate metabolism in T cell activation and exhaustion
No full textCD8+ T cells are critical mediators of immunity against infected and malignant cells, but differentiate into a state of dysfunction, known as exhaustion, after experiencing persistent TCR stimulation and metabolic stress in the tumor microenvironment (TME). Exhausted T (Texh) cells are characterized by the sustained upregulation of co-inhibitory molecules and reduced stemness and polyfunctionality. The TME creates an immunosuppressive metabolic environment via reduced levels of vital nutrients and oxygen, combined with increased catabolic waste products. Additionally, highly glycolytic tumor and stromal cells secrete lactic acid, which acidifies the extracellular space. T cells have high metabolic plasticity and have been shown to metabolize lactate. Here we investigate the role of lactic acid metabolism during T cell synapse formation and lactic acid metabolism in Texh cells infiltrating tumors. We found that during T cell activation, T cells restrict aerobic glycolysis to the T cell synapse. Additionally, we found that LDH bound the transcripts of many effector and metabolic genes in naïve T cells. Furthermore, we investigated the lactic acid metabolism of tumor infiltrating Texh cells. We found that Texh cells upregulate a newly characterized monocarboxylate transporter, MCT11 (encoded by Slc16a11), enabling uptake of lactic acid which can drive their dysfunction. MCT11 expression requires both the core exhaustion transcriptional program induced through chronic activation and metabolic stress signals, like hypoxia, originating within tissues. While overexpression of MCT11 in tumor- specific T cells decreased their polyfunctionality, conditional deletion of MCT11 in T cells reduced lactic acid uptake in Texh cells and improved effector function and response to immunotherapy. Further, a monoclonal antibody targeting MCT11 reduced lactate uptake
specifically in Texh cells, which, when used therapeutically in tumor-bearing mice, resulted in significantly reduced tumor growth, inducing complete regressions and immunologic memory in lactate-rich tumors. Our data support a model in which the exhaustion program upregulates MCT11, rendering exhausted T cells sensitive to toxic lactic acid present at high levels in the tumor microenvironment. MCT11 represents an attractive target to edit in therapeutic T cells or block using antibodies to render exhausted T cells impervious to lactic acid, allowing for tumor eradication
Enhancing Maternal Healthcare for Latina/Hispanic Women/Birthing People during the Perinatal Period in the United States Through the Social Ecological Model
No full textThis essay explores the barriers and facilitators to maternal healthcare services for Latina/Hispanic women/birthing people in the United States, structured around the social ecological model (SEM) across the prenatal, labor and delivery, and postpartum periods. It identifies that Latina women/birthing people encounter several barriers, such as language challenges, transportation difficulties, systemic discrimination, which hinder access to adequate and timely maternal care. These barriers are analyzed across the individual, interpersonal, organizational, community, and policy levels of the SEM. In comparison, facilitators like Spanish- proficient providers, doula and partner support, and culturally appropriate health education programs are highlighted as key to improving healthcare engagement and outcomes. This essay highlights the need for improving communication strategies and support systems within healthcare environments to foster a more inclusive and accessible maternal care experience for Latina women/birthing people. The findings indicate targeted interventions that can address these challenges, promoting better health outcomes for Latina mothers and their infants. The essay includes recommendations for future programs and policies to bridge existing gaps and empower Latina women/birthing people within the healthcare system
A Generation Rising: Education for Freedpeople in Post-Abolition Jamaica, 1834-1872
No full textMy dissertation explores the role of education in Jamaica from abolition in 1834 to the aftermath of the 1865 Morant Bay Rebellion. There is not a single story of education in Jamaica, but rather, multiple ones; between missionaries, planters, and freedpeople, no single group expressed a monolithic perspective on the role of schooling in Jamaica after abolition. Access to education became a new frontier for freedpeople, as well as a new target for conflict. The type of education offered to Black children and adults during the post-emancipation period sometimes reinforced racialized stereotypes about them and hindered upward mobility, even as it also provided narrow access to skills and knowledge that some freedpeople valued; paving the way for more opportunities for Black and mixed-race Jamaicans to pursue jobs as teachers and preachers. Planters feared that educating Black Jamaicans might provoke thoughts of rebellion that could echo Haiti’s path to liberation. Missionaries promised education would bring Christian virtue. Actual school attendance figures tell another story: of the hardships and hopes that gave rise to freedpeople engaging and disengaging tactically and practically with schooling in post-emancipation Jamaica.
Whether attendance at available schools reflected a component of free community life, or represented a new kind of compelled labor was an open question. Tensions over this issue, shaped by the animosity between freedpeople and those in positions of power, persisted decades after the abolition of apprenticeship in 1838 and spilled over in times of economic depression. The impact of unforeseen environmental and economic conditions on Black families typically affected their level of engagement with educational institutions, and ultimately, freedpeople prioritized family survival. Afro-Jamaican parents sometimes required their children to miss school in favor of tending the family’s provision grounds or helping with domestic labor. Amid times of intense socio-economic distress, such as during epidemics and droughts, some children would stop attending school altogether until conditions improved. Despite the planters’ efforts to promote education as a mechanism of control, rather than one of possibility, freedpeople continued to live as active agents of their own destinies by carving out the meaning of freedom for themselves
Skeletal Muscle Adiposity, Cognitive Function and Sleep Patterns in Adults of African Ancestry: Insights from the CARDIA and Tobago Health Studies
No full textSkeletal muscle adipose tissue infiltration (myosteatosis) increases cardiometabolic diseases risk. Myosteatosis is greater in individuals of African ancestry (AA) and in women, who are at higher risk of Alzheimer's disease and Related Dementia (ADRD). Visceral adiposity has been linked to dementia and cognitive decline, yet the relationship between myosteatosis and cognition is unclear. Given the importance of myosteatosis in cardiometabolic health, it is critical to examine the association of myosteatosis with cognitive function and its decline and determine if associations are independent of cardiometabolic disorders. Additionally, the impact of emerging lifestyle risk factors, like short sleep duration, on myosteatosis, has not been thoroughly explored, especially in AA Caribbean populations. This doctoral dissertation fills these gaps by investigating associations between myosteatosis, cognitive function, and sleep duration in AA and White adults.
The first aim was to examine the association between calf myosteatosis and cognitive function in middle and older-aged AA Caribbean women. Myosteatosis was inversely associated with information processing speed measured by the Digit-Symbol-Substitution-Test (DSST), an early indicator of cognitive decline. The second aim was to extend these findings by exploring the relationship between abdominal myosteatosis and 5-year cognitive decline in middle-aged U.S. White and AA men and women. Over five years, greater myosteatosis predicted cognitive decline, as measured by DSST, in White and female participants. The third aim was to examine the association of sleep duration with adiposity (general, central, and muscle) and cognitive function in AA Caribbeans. Longer sleep duration was significantly associated with lower BMI, reduced waist circumference, and lower calf myosteatosis. Despite these beneficial associations of longer sleep duration with adiposity, we found no association between sleep duration and cognitive function.
In summary, these findings emphasize the novel role of myosteatosis in brain health. We also show for the first time that sleep duration is an important risk factor for myosteatosis among AA individuals. Our work has significant public health implications, particularly for vulnerable and understudied populations such as AA middle-aged individuals, and women. Targeted interventions to mitigate dementia risk factors and improve overall health in diverse populations are critically needed
Cultivating Leaders within the University: Examining Effectiveness and Learning in Leadership Working Sessions
No full textThe goal of this work was to build the leadership aptitude of managers in the Enrollment Management Group (EMG) at Duquesne University and to study the efficacy of an intervention—two specific and intentional leadership working sessions. The project used an improvement science framework with survey and interview methods to determine to what extent the participant managers found the working sessions to have a positive effect on their practice and development. Many of the managers reported the sessions helped them to understand leadership development in new ways and brought them a greater awareness of themselves as leaders and their own leadership style. In engaging the managers as a group, the leadership working sessions generated discussions on pertinent issues facing the leadership team. Moreover, the discussions took on an atmosphere of problem solving and collaboration that the managers reported as being highly effective and something they had not engaged in previously. The sessions provided an avenue for the leaders to explore the organizational obstacles that prevented leadership development from taking root. Many staff in the office still felt the effects of previous leadership’s lack of investment in development, leaving the current leadership to manage through a variety of cultural challenges. While the managers face challenges in changing the culture of the organization, and some uncertainty on how to proceed in their leadership development, the sessions reinforced the idea that intentional leadership development works for higher education managers and demonstrated the value of investing greater time and resources in building leadership development into an organization’s culture. In drawing implications from these findings, it is evident that the EMG needs to take intentional actions—a mentorship program being one example—to begin instilling leadership development into its culture. If there is to be progress in leadership development, the project illustrated the need for it to be organization-wide
Investigating approaches for selective modulation of LOC efferent input to the cochlea
No full textThe lateral olivocochlear pathway (LOC) is an efferent pathway that originates from the lateral superior olivary complex and directly innervates the dendrites of auditory nerve fibers beneath inner hair cells. Investigating the LOC pathway has been difficult due to the lack of tools that would allow for direct and specific manipulation of the LOC pathway. In chapter 2 of my thesis, I explore the use of retrograde Adeno-Associated viruses (AAVs) for inner ear gene delivery to LOC neurons and report on the remarkable ability of the AAV2-retro serotype to spread throughout the central nervous system and onto the contralateral cochlea when it is unilaterally delivered to the inner ear. In chapter 3 I characterize a novel mouse line, X-Cre, that would allow for the selective manipulation of the LOC pathway. In chapters 4 and 5 I attempt to utilize the X-Cre mouse line to investigate its function during development and to investigate its modulation of auditory nerve activity in adult animals. Throughout both chapters, however, I encounter unforeseen issues that limit the specificity of the X-Cre mouse line to the LOC pathway. In chapter 6 I discuss potential approaches to restricting transgene expression in the X-Cre mouse line to the LOC pathway as well as alternative approaches for specific targeting of the LOC pathway beyond the use of the X-Cre mouse line
Funding Climate Action: New Grassroots Social Movements, Resource Mobilization, and the Role of Philanthropic Patronage
No full textThe year 2018 marked a pivotal moment for the global climate movement. The emergence of new grassroots groups like Fridays for Future, Extinction Rebellion, and the Sunrise Movement inspired hundreds of thousands of people to participate in diverse forms of climate activism. Resource mobilization theory (RMT), a key theory within social movement scholarship, stresses the importance of resources (e.g., time, money, skills, and organizational capabilities) in the emergence, development, and success of social movements. While a number of studies have identified resources as critical to environmental movements’ survival and influence, existing scholarship is relatively silent on how, and from where, new grassroots climate movements derive the financial resources necessary to support their mobilizations. Even less attention has been paid to the role and impact of philanthropic foundations in bankrolling climate activism. This study addresses this gap, asking: (1) How do recent climate change movement organizations secure the financial resources to sustain their activities? (2) What are the primary barriers that grassroots movements face when seeking funding from philanthropic foundations? (3) What are the implications of foundation patronage of grassroots climate change movements? Focusing on two climate movement cases (Extinction Rebellion UK and the Sunrise Movement), this study uses qualitative methods to analyze a number of data sources including 36 original, in-depth semi structured interviews with climate activists and foundation staff; ethnographic participant observations of climate activism in the UK and US; and a variety of secondary sources on climate movement funding. The findings demonstrate that philanthropic foundation funding played a significant role in the development of two of the most consequential grassroots climate movements to emerge in the climate wave of 2018. Regarding barriers to grassroots movement funding, I identify and detail a number of ‘foundation-social movement mismatches,’ that fall into three broad categories related to: (1) structure (legal status, organizational structure, grant size, timing, fluctuating interest in certain issue areas, as well as accessibility); (2) capacity and culture (human resource, labor, skills and expertise); and (3) theories of change (conflicting strategic and ideological orientations towards social change). I conclude by discussing potential pathways for overcoming these funding barriers