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Undergraduate Library Research Award Essay: "Histories of Privatization: Examining Culture, Legal Conflict, and Economic Transformation at Adams Morgan Plaza in Washington, DC"
No full textFirst-place winning essay in the Sophomore, Junior, or Senior category of the Undergraduate Library Research Award, presented by the Science, Engineering, and Social Sciences Libraries (SESSL).
Public spaces are disappearing at alarming rates as cities face mounting housing, economic, and social issues. Adams Morgan Plaza in Washington, DC is no different. Over the past several years, the Plaza has experienced numerous changes that have radically altered the neighborhood. It sparked community outrage and an ensuing lawsuit that wounds way, slowly, through the DC courts. This study uses census data and primary source documents to understand why Adams Morgan Plaza was privatized and how these changes are challenged. The results shed new light on how legal battles and economic pressures shaped the development of a central neighborhood landmark. It’s history as a theatre and communal epicenter are obscured by its liminality. The Plaza today contradicts Adams Morgan’s legacy of diversity and artistic culture,
but also finds itself on a new path: to create affordable housing. These findings provide insights into an ongoing history of change, cultural expression, and community within a vibrant neighborhood of the nation’s capital.
Keywords: Washington, DC; housing; historic preservation; Adams Morgan; public space; urban studies; economics; legal history; DC governance and politics; social and economic history
Representation of mental states in the primate brain
No full textA fundamental goal of neuroscience has been to study sensory perception, internal states, and observable behavior simultaneously. Traditionally, however, studies of the brain have often examined these processes separately, either by studying how individual neurons respond to specific sensory stimuli, or by tracking neural activity during overt movement.
What these approaches often fail to consider are mental states---that is, the underlying neural mechanisms of emotions and homeostatic needs, such as motivation, arousal, thirst and hunger---that influence perception and bias behavior. Even for affective neuroscientists studying emotions, longstanding limitations in both electrophysiological recording systems and accessible compute have made it difficult, if not impossible, to analyze the neural representation of mental states across multiple brain regions in a single experiment, while also holistically characterizing behavior using objective and analytical approaches.
Recent advances in electrode manufacturing, GPU architecture, automated spike-sorting methods, and computer vision models have ushered in a new era of neuroscience, in which mind, brain, and behavior can be studied in a more unified framework. Here I describe a new approach leveraging these advances to bridge the gap between studies of internal states and observable behavior in the primate brain.
I utilize state-of-the-art Neuropixels Non-Human Primate (NHP) probes to record from over one thousand neurons in multiple cortical and subcortical regions in a single experimental session, generating across many sessions the largest known dataset of simultaneous high-density recordings across primate amygdala, insula, and IT cortex. I synchronize the neural activity to multiple high-resolution video cameras pointed at the face and body, and train neural network models on the video data to identify key body parts in order to relate recorded neural activity preceding and during overt behavioral motifs.
I investigate mental states that are observable only in behavioral data, or only in neural activity, i.e. hidden from behavioral observation. Using analysis techniques rooted in both representational and dynamical frameworks, this dissertation argues that recording high-dimensional neural data alongside high-dimensional behavioral data is required to reveal the source and expression of emotions, emotion-based decision-making, and ultimately, cognition more broadly
Accounting Rules and Accountants
No full textI explore the role that accounting rules, in particular the restrictiveness of GAAP, have played in the declining number of accountants. I find that when exposure to restrictiveness is high, there are fewer students majoring in accounting, fewer CPA exam candidates, and fewer accountants and auditors overall.
The overall number of accounting positions that firms recruit for does not decrease when exposure to restrictiveness is higher – however, the nature of accountants’ work changes. There is less focus on tasks such as applying judgment, thinking creatively, and thinking critically and more focus on determining compliance. Despite the decrease in accountants, earnings for accountants do not increase, and the wage distribution becomes more compressed.
I supplement these analyses with a survey-based field experiment. Consistent with the archival results, the salience of restrictiveness deters students from entering the profession due to their inability to use creative and critical thinking. Overall, the findings suggest that restrictive regulation can shift the task content of occupations and reduce the pool of individuals interested in the profession
Undergraduate Library Research Award Essay: "Moral Code"
No full textSecond-place winning essay in the Sophomore, Junior, or Senior category of the Undergraduate Library Research Award, presented by the Science, Engineering, and Social Sciences Libraries (SESSL).
This essay describes the thought process (and usage of Columbia's libraries) for the creation of an interactive website which focuses on AI and technology ethics ("Moral Code")
A Novel Method for Assessing Word Finding Difficulty in Persons with Multiple Sclerosis: Semantically-Cued Retrieval of Exact Words
No full textMultiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) that results in damage to the myelin sheath that surrounds the neurons in the CNS. Resulting cognitive impairment is experienced by roughly 40% to 70% of individuals with MS. While research has historically focused on processing speed and memory deficits as the hallmarks of cognitive impairment in MS, more recent research has highlighted word finding impairment as a prevalent weakness experienced by those with MS, even early in disease. Such findings are in line with new neuroimaging research demonstrating cortical atrophy and lesion activity in language regions (e.g., left temporo-parietal regions) as part of the MS disease process.
Despite this, there remains little attention on language impairment in MS and existing research is often conflicted in quantifying deficits. These issues may stem from reliance on available expressive language metrics designed for use in aphasia and dementia populations, which are likely insensitive to the subtler “tip-of-the-tongue” phenomenon that is described by persons with MS. As such, the purpose of this dissertation was to investigate a more sensitive metric for objective word finding impairment in MS that better mirrors the word finding demands in everyday life. Furthermore, in line with research showing neuropathological changes in left temporo-parietal regions (e.g., planum temporale), this dissertation investigated if patterns of cortical thickness were associated with performance on this word finding metric and if this hypothesized relationship was mediated through differences in phonological processing ability, given previous research showing this skill as an area of weakness in persons with MS.
A sample of 172 persons with relapse-onset MS participated in objective cognitive assessment and self-report questionnaires at two timepoints. A subset of this group (n=132) also underwent 3.0 Tesla magnetic resonance imaging (MRI) at timepoint 1. The primary outcome of this study was objective language performance, quantified by both existing language metrics (e.g., verbal fluency, rapid automatized naming), and the novel paradigms of cued semantic retrieval and phonological processing. One predictor was patient-reported language complaints, assessed by the following questions: (a) having a word ‘on the tip of your tongue’ but with difficulty getting it out, (b) having a sense of what you want to say, but having trouble clearly expressing your thoughts, (c) accidentally saying the wrong word / misspeaking. Disease burden (cortical thickness) was also used as a predictor. Mood (Mental Health Inventory-5 (MHI-5)), vocabulary knowledge (NIH Toolbox Picture Vocabulary test), age, sex, and bilingualism were included as covariates.
As hypothesized, results revealed that cued semantic retrieval was the only objective language task related to expressive language difficulty, such that worse performance on cued semantic retrieval was associated with more severe/frequent expressive language complaints. Furthermore, performance on cued semantic retrieval was correlated with thinner left temporo-parietal regions of interest, specifically in the planum temporale. Lastly, this relationship between thinner planum temporale and worse cued semantic retrieval performance was significantly mediated through performance on a phonological processing task.
Taken together, results demonstrate the cued semantic retrieval is sensitive to patient-reported expressive language concerns and associated with cortical thickness patterns in relevant language regions, highlighting this task’s feasibility as an objective word finding measure. That phonological processing mediated this relationship suggests a potential mechanism for word finding impairment in persons with MS. However, because results are cross-sectional, it cannot be definitively concluded that such a relationship is disease-related, and it may be that developmental weaknesses in phonological processing serve as a risk factor for later word finding impairment in persons with MS. As such, future research should investigate this relationship longitudinally and using other neuropathological markers of disease burden (e.g., cortical lesions) to confirm that such findings are disease-related
Capturing COVID-Era Isolation and Illness in Poems: A Book Review of "Days of Grace and Silence"
No full text"Synapsis: A Health Humanities Journal" was founded in 2017 by Arden Hegele, a literary scholar, and Rishi Goyal, a physician. Its mission is to develop conversations among diverse people thinking about medical and humanistic ways of knowing ... as a “Department Without Walls” that connects scholars and thinkers from different spheres
Essays in Political Economy and Public Economics: Information, Institutions, and Behavior
No full textThis dissertation examines how the structure and flow of information shape individual decision-making and collective outcomes. Across three essays, it explores how social networks influence voter knowledge and participation, how allowing delegation in a voting system affects information aggregation, and how a program providing early information about college affordability affects educational attainment. Together, these essays study how institutions interact with and shape information environments, and the consequences for decision-making.
In Chapter 1, I study how political boundaries impact social learning. Informed voters are essential for government accountability, and social networks are an important avenue through which voters acquire political information. However, U.S. House of Representatives districts do not necessarily align with social networks. This misalignment potentially impacts the ease with which voters learn about their representatives, by altering the chance of encountering friends who provide relevant political information. I study whether the alignment between district boundaries and social networks affects voter knowledge, turnout, and campaign contributions in congressional elections. Using Facebook’s Social Connectedness Index and an event study design, I find that an increase in the share of friends living in the same district increases voters’ knowledge about their representative. For example, a 10 percentage point increase in this share raises the probability that a voter knows their representative’s party by 3.3 percentage points; this represents a 5\% increase over the mean. Additionally, a higher share of friends in the same district increases voter turnout in House elections and shifts campaign contributions towards own-district House candidates. I use a model of information diffusion to simulate the share of informed voters under counterfactual district maps, creating a framework to evaluate the informational effects of alternative maps. These findings suggest that aligning political boundaries with social networks can enhance democratic engagement.
In Chapter 2, coauthored with Joseph Campbell, Alessandra Casella, Lucas De Lara, and Dilip Ravindran, we study whether Liquid Democracy---in which decisions are taken by referendum, but voters can delegate their votes freely---can improve over existing systems in terms of information aggregation. We show that when better informed voters are present, delegation can increase the probability of a correct decision. However, delegation must be used sparely because it reduces the information aggregated through voting. In two different experiments, we find that delegation underperforms both universal majority voting and the simpler option of abstention.
In a tightly controlled lab experiment where the subjects’ precision of information is conveyed in precise mathematical terms and very salient, the result is due to overdelegation. In a perceptual task run online where the precision of information is not known precisely, delegation remains very high and again underperforms both majority voting and abstention. In addition, subjects substantially overestimate the precision of the better informed voters, underlining that Liquid Democracy is fragile to multiple sources of noise. The paper makes an innovative methodological contribution by combining two very different experimental procedures: the study of voting rules would benefit from complementing controlled experiments with known precision of information with tests under ambiguity, a realistic assumption in many voting situations.
In Chapter 3, I study a program that aims to increase college enrollment by addressing both financial and informational constraints. These "early commitment'' programs provide free tuition but require participants to sign up years before graduating high school. The goal is to ensure that students learn early the academic requirements for college and gain certainty about college affordability. This chapter examines an early commitment program in Oklahoma that is unique in its broad eligibility (families earning below median income) and its policy of not revoking scholarships if family incomes rise after sign-up, potentially enhancing certainty for participants.
Using synthetic control methods, I study the program's impact on college enrollment, high school completion, and standardized test scores. Among 18-19 year-olds, I find no consistent evidence of impacts on college enrollment or high school graduation. However, across specifications, I find a decline in the share of high school dropouts among 18-19 year-olds. This suggests the program may encourage students to remain in school longer, possibly to complete courses to meet scholarship eligibility requirements. Consistent with this, I replicate Bucceri (2013)'s finding that college enrollment increased among 18-21 year-olds from families earning less than $50,000. I also find an increase in high school graduation rates for this group. Additionally, I find evidence suggesting a decline in ACT scores but no consistent effect on SAT scores. Given test-taking patterns in Oklahoma, if the program encourages marginal students to prepare for college, it is unsurprising to see lower ACT scores and no effect on SAT scores, as the latter group was likely college-bound regardless
How can governments and investors successfully invoke positive human rights obligations in international investment law and arbitration?
No full textPositive obligations stemming from international human rights law require states to realize fundamental rights. This Perspective argues that those human rights obligations may serve as basis for the conceptualization of a duty to regulate in investment law. Furthermore, it reflects on the implications this may have for investment arbitration
RNA-templated DNA synthesis in antiviral immunity and genome evolution
No full textThe conventional flow of genetic information proceeds from DNA to RNA to protein, and yet reverse transcriptase (RT) enzymes that reverse this flow are widespread across all three domains of life. Many RTs are associated with RNA-based mobile genetic elements (MGEs), promoting their maintenance and propagation by copying them for long-term storage in DNA genomes. However, expanded surveys of RT diversity have revealed that a substantial fraction of these enzymes lack any apparent connection to MGE mobility, implying that they have been repurposed for distinct cellular roles.
In this work, I investigate the mechanisms and biological functions of an enigmatic bacterial RT family, termed defense-associated RTs (DRTs), and uncover a remarkable diversity of pathways through which reverse transcription mediates immunity against bacteriophages. By integrating high-throughput sequencing, genetics, biochemistry, microbiology, and bioinformatics approaches, I demonstrate that DRT enzymes catalyze the synthesis of de novo genes, DNA homopolymers, and tandem-repeat products — each functioning in unique ways to confer phage defense.
Furthermore, elucidation of the repetitive DNA synthesis mechanism employed by DRT enzymes reveals an evolutionary link between this bacterial RT family and eukaryotic telomerase. This finding points to an ancient bacterial origin for the DNA repeat addition mechanism that safeguards genome integrity across nearly all eukaryotes. Collectively, this work expands the conceptual boundaries of the genome, highlights novel noncoding functions of DNA, and uncovers a striking diversity of previously unrecognized cellular roles for RNA-templated DNA synthesis
Mining terms: “Use-it-or-lose-it” provisions
No full text"Use-it-or-lose-it" provisions in mining laws and contracts compel timely and sustained production, preventing firms from hoarding mineral rights without development. Especially vital amid global competition for “critical” resources, these clauses protect host states’ economic interests by ensuring expected resource income and employment, deterring speculative behavior and guiding granting of waivers