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A Modular and Standardized Pipeline for the Design and Fabrication of Dielectric Elastomer Actuator Multilayers
No full textThe development and deployment of DEAs has been severely limited by the slow and laborious design and manufacturing pipeline used to produce them. I have developed several elements of a pipeline that accelerates design and fabrication by standardizing and modularizing them. This allows for the easy development of task-specific devices, enhances their performance, and makes them scalable enough to be deployed in commercial products. Splitting elastomer deposition and assembly into modular processes allowed me to accelerate throughput, scale actuator size and quantity, and incorporate a variety of elastomer dielectrics by decoupling the interactions between materials and successive steps. Similarly, by spatial patterning of NP inks, I was able to decouple the advantages and disadvantages of each ink, allowing for modular, independent tuning of each ink to suit a single purpose. This allowed for faster development and higher-performance devices. My work automating the pre-clearing possible made it possible for each newly-designed device to be cleared quickly and with minimal labor, and my quantification and quantification of the process delivers the reliability necessary for an industrial process and product
The Long Arc of a Nation: Memory Politics in Canada and the United States
No full textIn Canada and the United States, there are ongoing debates about how the nation’s history should be remembered, including what should be included or excluded from educational curricula and which historical figures are worthy or unworthy of being honored with statues or memorials. Many of these memory politics disputes have focused on the legacies of racism and colonialism in the two countries, a trend which coheres with the proliferation of race, ethnicity, and indigeneity as topics in the public discourse. In this dissertation, I examine the dynamics of memory politics through a comparative analysis of the two countries, specifically focusing on four metropolitan areas: Boston, Minneapolis, Toronto, and Vancouver. I began with a content analysis of 165 newspaper articles published in major outlets that addressed topics related to the history of race, ethnicity, and indigeneity. I use the content analysis to identify salient themes of memory politics disputes in each context, including which aspects of national history are most frequently contested, the cultural repertoires employed during these disputes, and which ethnoracial groups are most frequently invoked during these discussions. To ensure the interviews spoke to the issues and concerns that were most likely to be relevant to the interviewees in each context, I also used this analysis to develop vignettes and refine the questions included on the interview guide.
I organize my findings into three empirical chapters. The first empirical chapter examines how recent events have prompted many Canadians and Americans to reconsider taken-for-granted narratives about national exceptionalism that are linked to the belief that the nation has achieved racial equality. The second empirical chapter focuses on the perceived stakes of memory politics disputes. Drawing on the concept of recognition, I find that interviewees are seeking recognition through historical representations. I identify four dimensions of the struggle for recognition in memory politics disputes: visibility, significance, adversity, and contributions. In the third empirical chapter, I describe how white interviewees in Canada and the United States perceive their personal status and the collective status of white people as a group in the context of memory politics disputes. Consistent with prior research on the racial attitudes of white people, I find that some interviewees downplay or dismiss the impact of historical racism on present-day inequalities and oppose any additional programs for redressing racial inequality. However, some white interviewees emphasized that racism and colonialism are directly connected to present-day inequalities and emphasized the need for more racial justice initiatives, a perspective that would undermine their privileged status in society. I find that those in the latter group do not feel a sense of racialized group status threat and employ the concept of linked fates to explore why this might be
"Stammering Elocution": Disfluency and Disability in Modern American Poetry
No full textThis study shows how the experiences, metaphors, and insights of communication disability are an overlooked but crucial factor for understanding the work of four American poets, William Carlos Williams, Theresa Hak Kyung Cha, Sonia Sanchez, and Bernadette Mayer. The poets I study radically refashion poetic form as they manage audience expectations surrounding their own provocative, disfluent voices. In so doing, their work reconceptualizes how we might think of voice and identity in poetry, as they innovate poetic form in response to changing social contexts. In the Introduction, I develop the concept of disfluency in light of paradoxical theories of poetic voice, the contextual nature of fluency, and the recent shift in disability studies toward cognitive disability, the connections between disability and rhetoric, and a relational model of disability.
In Chapter 1, I argue for the significant role that William Carlos Williams’s post-stroke embodiment and aphasia play in his late-career poetry and performances. Williams wrote collections such as The Desert Music (1954) and Journey to Love (1955) with the expectation of performing them, and when we listen closely to the available recordings of Williams’s reading his work, it becomes apparent that what Williams called “the variable foot” offers an accessible formatting that makes both composing and performing possible for his disfluent poetic voice. Listening closely to Williams’s audio archive also reveals many moments in which Williams explains his newfound difficulties with speech, even as he continues to tout the “American idiom” and its potential for postwar American poetics.
In Chapter 2, I look to the work of Theresa Hak Kyung Cha, especially her 1982 book Dictée, to argue for how Cha’s intermedial experiments with language upset hegemonic conceptions of fluency. Taking up Ed Park’s suggestion that Dictée is an “eloquent stutter” of a text, this second chapter makes a broader claim about the relationship between poiesis and varieties of “broken” language, as well as critics’ propensity for grasping at metaphors of disability to describe nonstandard language use. Paying careful attention to stuttering (both literal and figurative) in a text as suggestive as Dictée opens up other modes of eloquence outside of supposedly self-evident fluency. As Dictée, in addition to Cha’s earlier work such as Mouth to Mouth, stretches the limits of language’s shapes and sounds, Cha’s work offers an opportunity to think about disfluency beyond the disability studies context of the previous chapter.
Chapter 3 looks at the long career of Sonia Sanchez, as I follow the repetitions and rhythms of stuttering across Sanchez’s vast poetic corpus, interviews, and recordings of her performances. I argue for how Sanchez’s reading voice—and indeed, her genuine chorus of voices and different vocal styles—incorporates disfluency, music, and different languages to uncanny rhetorical and poetic effect as she talks back to the social forces that would otherwise silence her. While the critical narratives about Sanchez’s poetic voice focus on her childhood and adolescent “overcoming” of stuttering, I survey poetry from across her sixty-year career to illustrate stuttering’s long-standing influence on her poetics. I conclude by locating Sanchez’s legacy in the work of Douglas Kearney, JJJJJerome Ellis, and Tracie Morris.
In Chapter 4, I read the early- and late-career poetry of Bernadette Mayer in order to recognize the significance of disfluency, disability, and neurodivergence in Mayer’s late-career practice. This chapter speaks to how her post-stroke experience significantly altered her writing practice and daily life, but I also explore how Mayer in her early career challenged dominant assumptions about how an experimental poet was supposed to express her voice in poetry. I show not simply how disability disrupts Mayer’s famously intense methods of writing, but rather how she incorporates the lived experiences of disability and neurodivergence—these nonstandard ways of thinking, moving, and communicating—into a body of work that has always challenged the social perception of women’s expression.
Lastly, in the Coda, I consider my experience meeting Mayer, my own experience as a stutterer, and—via the theories of Michel de Certeau and Henri Lefebvre—the potential of disfluency to disrupt the rhythms of everyday life
A bipartite mechanism for IGF2BP1 in regulation of fetal hemoglobin
No full textDespite over a century of work on hemoglobinopathies, among them sickle cell disease, a complete understanding of hemoglobin switching and factors regulating hemoglobin expression remains incomplete even as the first CRISPR/Cas9 gene therapy has obtained approvals for the treatment of transfusion-dependent β-thalassemia and sickle cell disease.
DDX6, an RNA helicase and P-body nucleator associated with miRNA-mediated RNA decay and was identified as an HbF repressor in a genome-wide CRISPR screen performed in our lab. I performed a CRISPR tiling screen on DDX6 using SpRY-ABE8e-Cas9 to achieve near base-pair resolution and identify a well-tolerated variant that induces fetal hemoglobin expression, useful to enable the further study of the role of DDX6 in regulation of fetal hemoglobin.
I studied factors regulating the heterochronically silenced m6A RNA-binding protein IGF2BP1 which has been identified as a positive regulator of fetal hemoglobin expression by suppressing BCL11A expression. In contrast to this observation, post-transcriptional control by IGF2BP1 generally acts through improving the translation and mRNA stability of IGF2BP1 target mRNAs in an m6A-dependent manner. To better characterize the IGF2BP1-mediated mechanism responsible for control of fetal hemoglobin expression, I assessed whether BCL11A was required for IGF2BP1-mediated regulation of fetal hemoglobin and discovered a direct BCL11A-independent mechanism. I developed a luminescent transgenic reporter to disentangle the BCL11A¬¬-dependent and newly identified BCL11A-independent mechanisms and used it discovered that IGF2BP1 directly supports the translation of HBG mRNA in a manner requiring an intact stop codon-proximal m6A motif. In addition to this BCL11A-independent mechanism, I identified that the BCL11A-dependent mechanism relies on IGF2BP1-mediated post-transcriptional control of HIC2, which indirectly supports fetal hemoglobin expression via suppression of BCL11A.
This work establishes a strategy for near-base pair resolution CRISPR base editing screening and validation of variants of interest in a novel fetal hemoglobin reporter cell line. This gene, DDX6, is likely involved in post-transcriptional control of factors regulating fetal hemoglobin. Additionally, I characterize a heretofore misunderstood BCL11A-dependent mechanism for IGF2BP1 in regulating fetal hemoglobin expression while simultaneously identifying a novel direct effect of IGF2BP1 on the fetal hemoglobin RNA, a strategy with potential to be exploited for the improved expression of lentiviral gene therapy vectors delivering HBB for sickle cell disease or transfusion dependent β-thalassemia.Medical SciencesMedical Science
Are Carbon Emissions Associated with Stock Returns?
No full textAn influential emerging literature documents strong correlations between carbon emissions and stock returns. We re-examine those data and conclude that these associations are driven by two factors. First, stock returns are correlated only with unscaled emissions estimated by the data vendor, but not with unscaled emissions actually disclosed by firms. Vendor-estimated emissions systematically differ from firm-disclosed emissions and are highly correlated with financial fundamentals, suggesting that prior findings primarily capture the association between such fundamentals and returns. Second, unscaled emissions, the variable typically used in academic literature, is correlated with stock returns but emissions intensity (emissions scaled by firm size), an equally important measure used in practice, is not. While unscaled emissions represent an important metric for society, we argue that, for individual firms, emissions intensity is an appropriate measurement choice to assess carbon performance. The associations between emissions and returns disappear after accounting for either of the issues above.Version of Recor
Toward a Sensor for DNA Supercoiling
No full textDNA in the cell takes on a double helical structure that is then formed into larger loops, compacting into a supercoil. These supercoils are the result of mechanical torsional forces caused by over or underwound DNA. Supercoiling plays a strong role in chromatin compaction and gene expression; and the work of topoisomerases, which wind and unwind the DNA, are able to change topology of the DNA to facilitate transcription or replication. Despite the importance of supercoiling in DNA topology and DNA’s cellular function as a whole, there is not currently a single molecule sensor that can measure the degree of DNA supercoiling in vivo in real time.
This thesis proposes a design, synthesis protocol, and incorporation protocol for a sensor that reports twist in DNA strands via fluorescence lifetime imaging (FLIM). The protocol proposed here suggests a synthesis derived from the commercially available FlipperTR molecule, resulting in a sensor that can be attached to alkyne-painted DNA strands via a bioorthogonal Click Chemistry reaction.
Additionally, this thesis performs testing in vitro and in vivo in Escherichia coli of the proposed supercoiling sensor in order to establish its potential as an high-resolution in vivo reporter for twist in the genome. Data from this testing indicate that the sensor can be incorporated into the genome as proposed and does respond to torsional state in DNA via FLIM
Chiroptera: A Biomimicry Inspired Approach to Simultaneous Localization and Mapping for Autonomous Vehicles
No full textBiomimicry is a technique for solving complex technical challenges by applying biologically inspired processes. When considering flight through challenging conditions, bats (order chiroptera) have demonstrated a keen ability to use non-visual senses to navigate surroundings, avoiding obstacles, and create a mental map of the environment in which they live and operate.
Unmanned aerial drones are controlled in flight by an intelligent agent, be it a human pilot or artificial intelligence (AI) based autopilot. Simultaneous Localization and Mapping (SLAM) is a technique for building a map of an environment while keeping track of a vehicle’s position within that environment. This thesis shows that is possible to use bats as the inspiration for the development of an AI autopilot, Chiroptera, that can conduct SLAM operations to navigate a drone through an unknown environment. A bespoke 3D drone flight simulator, Bat Cave, will be developed concurrently within which Chiroptera’s SLAM capabilities can be tested and its behavior refined
Essays on the Use of Information in Financial Intermediaries
No full textMy dissertation explores capital market information flows, going beyond the usual focus on firm-to-investor communication. In the second and third chapters, I delve into the role of information in investment delegation among investors. I study private equity, a financial intermediary that is rapidly growing yet whose operating model is less known to accountants. And I find that regulatory intervention on information rights is important for private equity investors, despite the traditional assumption that they safeguard their own rights. Moreover, I also find that asking fund managers to disclose conflicts of interest is not enough; the effect depends on whether managers face public enforcement. In the fourth chapter, I, together with Miao Liu and Rachel Zhang, examine the \textit{inverse} information flow from investors to managers. Specifically, we explore the plausible yet puzzling argument in accounting literature: whether investment-Q sensitivity captures managers’ learning from the capital market, and if so, when and how they learn. Our evidence offers two insights. First, learning is concentrated in a short period of time when stock price movements provide a relatively clean binary signal for managers to act upon. Second, learning from prices can be supplemented by face-to-face discussions with institutional investors, which provides the context for managers to interpret investors’ trading decisions
Genomic methods for the surveillance and epidemiologic inference of respiratory viral pathogens
No full textRespiratory viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and respiratory syncytial virus (RSV), are globally circulating pathogens with a substantial disease burden. Epidemiologic and genomic approaches to surveil respiratory viruses guide public health efforts and advance our understanding of viral evolution and transmission. However, interpreting respiratory viral surveillance data can be challenging, as data collection is often (i) biased, in that epidemiologic and genomic data are primarily derived from cases exhibiting moderate or severe disease; and (ii) dynamic, in that surveillance practices evolve in response to diagnostic practices, methodologic advances, and public health priorities. In this dissertation, I develop methods to mitigate the biases inherent in traditional respiratory viral surveillance approaches, and apply them to study the epidemiology and evolution of both SARS-CoV-2 and RSV. In Chapter 2, I use scalable genomic tools and samples from universal SARS-CoV-2 testing programs to conduct population-wide genomic surveillance, providing a comprehensive view of the Omicron variant’s arrival and spread in university communities. In Chapter 3, I develop an experimental protocol to sequence viral genomes from at-home rapid antigen tests, allowing genomic surveillance to extend to individuals who do not seek clinical diagnostic testing. In Chapters 4 and 5, I investigate the increase in RSV cases reported after the emergence of SARS-CoV-2. I demonstrate that increased respiratory viral testing, rather than the evolution of a more severe or transmissible RSV variant, can explain the apparent increase in cases. Moreover, I establish quantitative approaches to estimate epidemic parameters under the counterfactual scenario in which viral diagnostic testing remained unchanged. In summary, I develop robust genomic and epidemiologic surveillance strategies and demonstrate their ability to generate actionable insights into the evolution and transmission of respiratory viruses
The Cuban Hypothesis: Aesthetics and Politics of Continuity & Rupture since the Radical Sixties
No full textThe different discourses (political, aesthetic, historiographic) that dispute since the 1960s the currency of Cuba’s recent past have consistently articulated their narratives around the figures of continuity and rupture—from the “new man” in a new Cuba to the existence of a Cuba “post Castro.” In actuality, these tropes, which refer to the passage of time, have been employed instead to discuss the synchronic relationships between political subjects and state politics—between society and government, the people and the leadership, Cuba and Fidel. In this dissertation, I challenge the rhetorical inversion of historical and political terms by proposing an alternative articulation of these synchronic agents of politics. The exceptionality of the process of social revolution in Cuba consists in a form of politics where power is never neither a predicate exclusive to the state or the people nor a negotiation of periodic tensions between them, but is always simultaneously held by both.
This dissertation historicizes the material and symbolic conditions of possibility of this dual power to produce three critical, historiographic, and theoretical interventions.
Firstly, to offer a mode of reading that makes the instances of actualization of this dual power visible in the forms of representation that registered it, primarily in Cuban cinema and literature. With the theoretical help of political historian Theda Skocpol and philosophers Alain Badiou and Jacques Rancière, I rethink the category of the “special plans” utilized in the economic history about the second half of the 1960s to define the elements and dynamics of dual power in Cuba and argue their effects in the cultural field and the realm of everyday life. Mass mobilization, rather than an economic strategy, constituted a form of political participation that was lived of as a social pharmakon, as I read it in the testimonies and creation of Silvio Rodríguez and Cintio Vitier. It was also in those actions of mass voluntary labor that Cuban cinema evolved both institutionally and aesthetically, a progression that is more evident in the theoretical writings of Julio García Espinosa and Tomás Gutiérrez Alea. New cinematic forms were found in literal sync with the radicalization of political participation in the different special plans launched during the decade and documented by the core of Cuba’s film industry—the Noticiero ICAIC Latinoamericano.
The figures of historical continuity and rupture are also forms of negotiating in the surface of cultural production the realms affected by the historical process of a social revolution, between everyday life and the historic event; that is, these tropes need to be read as a negotiation of the degree of importance of the revolutionary process, what it managed to generate for the future, as well as the level of agency of its Cuban participants—between subjective transformation or the formation of a political subjectivity. By thinking about the quotidian in terms of Bruno Latour’s new materialism, I rename a popular genre of film comedies from the 1980s as Socialist Costumbrismo to highlight its connection with the new country’s material realities, social relationships, and the political logics and collective fictions that sustained it. I revisit a series of understudied short films from this genre to disentangle contemporary forms of establishing cultural memory about the Cuban past from an archival curation of the material culture of the time that renders the latter obsolete and devoid of relevance for the post Soviet present. Against that archival drive in projects such as the online collections Cuba material and the Archive of Cuban Socialism (ARCHUS), I read these shorts by filmmaker Enrique Colina with Diana Taylor’s ideas about the repertoire to restitute their revolutionary potential and the implicit collective forms of politics to the material everyday life they represent.
Secondly, this dissertation theorizes the changing forms of the Cuban dual power to rethink the history of the Revolution against the prevalence of historiographic narratives of rupture in the interpretation of contemporary cultural production. Critics approach the Cuban visual and literary production in the decades after the dissolution of the Soviet Union as retreating from a utopian future, mourning a revolutionary past, or coping with a paranoid present. This critical description portrays a cultural scene devoted to dispassionately represent an omnipresent societal suspicion towards any collective project. The final chapter of this dissertation questions this portrayal and reveals, on the contrary, a deeply politically engaged cultural field invested in a programmatic retelling of the revolutionary aftermath. By employing Žižek’s political translation of Freud's different conceptualizations of trauma, I register a semantic and narratological change in the usage of the motif of death and interpret it as a central signifier of a new politics of memory at work on the Island. Based on the traditional Marxist and Perry Anderson’s concepts of ideology, I read a historical form of discursivity in literary works by Leonardo Padura, Pedro Juan Gutiérrez, Karla Suárez, Eduardo del Llano, Fabián Suárez, and Ahmel Echevarría Peré, as well as in films by Tomás Gutiérrez Alea, Daniel Díaz Torres, and Jorge Perugorría.
Lastly, this dissertation—engaging with the work of Alain Badiou, Slavoj Žižek, Jacques Rancière, Bruno Bosteels, Jodi Dean, and others—reintroduces the Cuban experience in contemporary debates about emancipatory theories—that is, Cuba as a hypothesis