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Review Of Scattered And Fugitive Things: How Black Collectors Created Archives And Remade History, Kai H. Uchida

Journal of Contemporary Archival Studies

In Scattered and Fugitive Things: How Black Collectors Created Archives and Remade History, historian and archivist Laura E. Helton tells the story of six individuals – Arturo Schomburg, Alexander Gumby, Virginia Lee, Dorothy Porter, Vivian Harsh, and Lawrence Reddick – whose practices of radical collecting revalued and recast the importance of Black history. Helton combines innovative methodological readings of previously undervalued archival sources with a keen understanding of archival practice to illuminate Black archives as a site of radical collecting, intellectual inquiry, and community empowerment. Compellingly written with insights about the theory of their curation and the story of …

Pricing And Production Without The Invisible Hand, Joel P. Flynn, George Nikolakoudis, Karthik A. Sastry

Cowles Foundation Discussion Papers

Modern theories of the business cycle do not allow for the simultaneous rational choice of both prices and quantities, instead assuming that an “invisible hand” determines one of these variables to clear markets. In this paper, we develop a macroeconomic framework in which both prices and quantities are chosen directly by firms, and exchange is both voluntary and efficient. Because of uncertainty about demand and productivity, individual product markets can be in excess supply or rationed. The absence of market-clearing changes pricing and production in qualitatively important ways: markups are no longer determined solely by the elasticity of demand, and …

Initial-Condition-Robust Inference In Autoregressive Models, Donald W. K. Andrews, Ming Li, Yapeng Zheng

Cowles Foundation Discussion Papers

This paper considers confidence intervals (CIs) for the autoregressive (AR) parameter in an AR model with an AR parameter that may be close or equal to one. Existing CIs rely on the assumption of a stationary or fixed initial condition to obtain correct asymptotic coverage and good finite sample coverage. When this assumption fails, their coverage can be quite poor. In this paper, we introduce a new CI for the AR parameter whose coverage probability is completely robust to the initial condition, both asymptotically and in finite samples. This CI pays only a small price in terms of its length …

Willingness To Travel With Endogenous Distance: Evidence From The Changing Retail Landscape, Yue Cao, Judith Chevalier, Jessie Handbury, Hayden Parsley, Kevin Williams

Cowles Foundation Discussion Papers

Economists often use variation in consumers’ distance from services as a source of demand variation. This approach typically treats consumer-supplier distance as exogenous, despite suppliers strategically choosing locations. We develop a novel class of instruments to address this endogeneity. These instruments exploit the spatial distribution of consumer demographics and can be constructed from standard cross-sectional data, making them useful in a variety of spatial applications. Our preferred instruments use the income composition of concentric discs centered on the Central Business District. Applying these instruments to smartphone geolocation data for millions of devices across 18 metropolitan areas, we estimate consumer preferences …

Human Capital And Development, Philippe Aghion, Ingvild Almås, Costas Meghir

Cowles Foundation Discussion Papers

Human capital is central to efforts to promote growth, convergence, and the elimination of poverty. Drawing on seminal macroeconomic frameworks by Nelson-Phelps, Lucas, and subsequent developments, alongside macro and microeconomic evidence, the chapter examines the role of human capital in driving innovation and growth, emphasizing how different types of human capital matter at different stages of development, and discussing obstacles to accumulation and evidence from policy interventions.

Wedges: A Microeconomic Perspective On Misallocation, Lauren Falcao Bergquist, Daniel Lashkari, Eric Verhoogen

Cowles Foundation Discussion Papers

This chapter, prepared for the Handbook of Development Economics (Vol. 6), reviews recent microeconomic evidence on the causes of resource misallocation in developing countries. It distinguishes between “technological” and “distortionary” wedges, develops a unified theoretical framework linking market power, taxes, financial frictions, and firm dynamics, and summarizes empirical findings from the “direct approach” to misallocation. The authors emphasize how wedges vary by firm size and discuss policy implications for improving allocative efficiency.

Information Design And Mechanism Design: An Integrated Framework, Dirk Bergemann, Tibor Heumann, Stephen Morris

Cowles Foundation Discussion Papers

We develop an integrated framework for information design and mechanism design in screening environments with quasilinear utility. Using the tools of majorization theory and quantile functions, we show that both information design and mechanism design problems reduce to maximizing linear functionals subject to majorization constraints. For mechanism design, the designer chooses allocations weakly majorized by the exogenous inventory. For information design, the designer chooses information structures that are majorized by the prior distribution. When the designer can choose both the mechanism and the information structure simultaneously, then the joint optimization problem becomes bilinear with two majorization constraints. We show that …

Extreme Points And Majorization, Andreas Kleiner, Benny Moldovanu, Philipp Strack

Cowles Foundation Discussion Papers

Many seemingly different economic problems share a common mathematical structure: they involve the maximization of a functional over sets of monotonic functions that are either majorized by, or majorize, a given function. This paper presents new, simpler proofs for the main characterization results of the extreme points of sets defined by monotonicity and majorization constraints obtained by Kleiner, Moldovanu, and Strack (2021). It demonstrates how these characterizations can be applied to a broad range of economic applications, including auction and information design, contest design, optimal delegation, optimal stopping, and decision problems under risk. The paper concludes with an overview of …

Methylenetetrahydrofolate Reductase (Mthfr) Polymorphisms And Neural Tube Defects In African Populations: A Global Meta-Analysis And Population Genetic Characterization In Uganda, Nana Ekua Entsiwa Adenu-Mensah

Yale Medicine Thesis Digital Library

Background: Neural tube defects (NTDs) affect 1.9 per 1,000 births globally, with the highest burden occurring in African populations that remain underrepresented in genetic epidemiology. The methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms reduce enzyme activity and have been associated with increased NTD risk in several populations, though their relevance across African regions remains unclear.

Methods: We conducted: (1) an updated systematic review and meta-analysis of MTHFR C677T and A1298C polymorphisms and NTD risk (66 studies, ~22,000 participants); (2) population-level genotype characterization of 978 Ugandan children using whole-genome sequencing; and (3), a comparative analysis of MTHFR C677T allele frequencies across …

Level Of Evidence And Cost Considerations In United States Clinical Practice Guidelines, 2019-2023, Omar Qureshi

Yale Medicine Thesis Digital Library

BackgroundClinicians rely on clinical practice guidelines (CPGs) to fulfill a dual mandate: practicing evidence-based medicine and ensuring cost-conscious stewardship of resources. However, it remains unclear whether modern CPGs provide the guidance necessary to meet these goals. Specifically, the extent to which recommendation strengths align with evidence quality and the prevalence of cost-related guidance within U.S. medical society CPGs remains unknown.

Research Aimsa) To examine the distribution of SOR and LOE ratings for recommendations offered by United States medical societies through CPGs and evaluate concordance between SOR and LOE ratings for CPG recommendations. Additionally, assess whether there are recommendation-level, guideline-level, or …

Clinical And Pathologic Factors Associated With Poor Outcomes In Cutaneous Sarcomas, Jennifer Rodriguez

Yale Medicine Thesis Digital Library

Background:Cutaneous sarcomas exhibit a broad spectrum of clinical behavior, ranging from indolent tumors to lesions with significant metastatic potential. In atypical fibroxanthoma, pleomorphic dermal sarcoma, and cutaneous leiomyosarcoma predictors of recurrence and metastasis are not always apparent at initial diagnosis. Improved understanding of clinicopathologic features associated with adverse outcomes is needed to guide risk stratification and management.

Objectives:To identify clinical and pathologic factors associated with poor outcomes in AFX, PDS, and cutaneous leiomyosarcoma and to evaluate the relationship between initial biopsy, definitive excision findings, and clinical outcomes.

Methods:This thesis comprises three retrospective cohort studies conducted at a single academic institution. …

Automated Cerebral Autoregulation Monitoring With Machine Learning, Matteo Rosati

Yale Medicine Thesis Digital Library

Background - Current methods of identifying patients in the neurological intensive care unit (NeuroICU) with disrupted cerebral autoregulation rely on statistical methods that require significant time to produce predictions. There is a need for faster algorithms that can minimize the secondary damage caused by disrupted autoregulation in these patients.

Research Aims - We aim to develop a machine learning (ML) model that determines whether a patient is outside optimal autoregulatory limits using continuously recordable and minimally invasive physiologic data gathered in the NeuroICU.

Hypothesis - We hypothesize we can use ML techinques to ingest physiologic data in short time windows …

Predictive Modeling Of Transfusion After Cranial Vault Remodeling For Pediatric Craniosynostosis, Paul Serrato

Yale Medicine Thesis Digital Library

Background: Cranial vault remodeling (CVR) for pediatric craniosynostosis is associated with postoperative blood transfusion, yet determinants of transfusion risk remain incompletely defined. Estimating transfusion risk preoperatively could support more personalized blood management planning for this population.Research Aims: To evaluate whether supervised machine learning models can reliably predict postoperative transfusion risk following CVR compared to traditional logistic regression and to identify the most informative predictors of those models. Hypothesis/Question: We hypothesized that ensemble machine learning approaches (e.g. random forest, extreme gradient boosting) would match or outperform logistic regression in predicting transfusion by leveraging nonlinear associations and higher-order interactions across patient, procedural, …

Leveraging Large Language Models To Augment Emergency Department Chest Pain Decision-Making, Conrad Safranek

Yale Medicine Thesis Digital Library

Background - Large language models (LLMs) can convert unstructured clinical text into structured, computable signals, creating a new class of clinical decision support (CDS) that is tightly coupled to real documentation workflows. This is especially relevant in emergency medicine, where decisions must be made rapidly under uncertainty, often with key information scattered across notes, reports, and prior encounters. Emergency department (ED) chest pain evaluation is a prototypical setting for this problem: it is high-volume, high-stakes, operationally costly, and driven by pathway-based triage and risk stratification, yet care remains heterogeneous across clinicians and teams. As health systems and electronic medical record …

Comparison Of Clinical Outcomes By Tube Type And Size Following Percutaneous Radiologic Gastrostomy: A 10-Year Retrospective Study, Diane Zhao

Yale Medicine Thesis Digital Library

PurposeTo compare the complication rate and time to the first reintervention of pull-type and push-type gastrostomy tubes placed under radiologic fluoroscopy guidance in adults. Materials and Methods During a 10-year period (2012-2022), 2341 adult patients underwent percutaneous radiological gastrostomy at our institution, and their charts were reviewed. 896 (39%) procedures were done with the push method, and 1393 (61%) were done with the pull method. Results Rates of significant hemorrhage at the surgical site, leakage at the site, and malplacement of the g-tube were not found to be statistically different between the two groups. However, push g-tubes were significantly more …

The Strength Of Association Between Surrogate Markers And Clinical Outcomes Used By The Fda For Chronic Disease Indications, Samuel Yoon

Yale Medicine Thesis Digital Library

The U.S. Food and Drug Administration (FDA) has traditionally required the use of clinical outcome measures as clinical trial endpoints to support the approval of new drugs. However, clinical outcome trials are typically large, lengthy, and expensive. To expedite this process, Congress has enacted several regulatory programs to facilitate FDA approval of new drugs on the basis of surrogate markers, endpoints that are reasonably likely to predict clinical benefit, as trial endpoints. However, the evidence demonstrating the validity and reliability is mixed, creating uncertainty for patients and physicians about the true clinical benefits of new drugs approved on the basis …

Prevalence, Reporting, And Management Of Interstitial Lung Abnormalities And Incidental Findings On Lung Cancer Screening, Tian Wei Yu

Yale Medicine Thesis Digital Library

Background: Low dose computed tomography for lung cancer screening frequently identifies incidental findings. The most frequent and consequential thoracic and upper abdominal incidental findings include interstitial lung disease (ILD), interstitial lung abnormalities (ILA), emphysema, coronary artery calcification, aortic calcification, aortic aneurysm, and adrenal lesions. Many of these abnormalities carry prognostic and therapeutic implications. However, the prevalence of these findings, variation in reporting practices, and downstream management within integrated health systems remain incompletely characterized, particularly for ILA and ILD.

Research Aims: We aimed to quantify the prevalence of selected incidental findings on lung cancer screening CT across a large multi-hospital health …

A Questionnaire Assessing Attitudes And Readiness For Hiv Pre-Exposure Prophylaxis Therapy For Community Members At-Risk For Hiv Acquisition In Liberia, Yishak Bedaso

Yale Medicine Thesis Digital Library

AbstractA Questionnaire Assessing Attitudes And Readiness For HIV Pre-Exposure Prophylaxis Therapy For Community Members At-Risk For HIV Acquisition In Liberia Yishak Bedaso;1 Jessica Tuan, MD, MS;2 Yassah M. Barclay-Korboi;3 Onyema Ogbuagu MBBCh, FACP, FIDSA4 Affiliation: 1. Yale School of Medicine, New Haven, CT, USA 2. Columbia University Vagelos College of Physicians and Surgeons, Department of Infectious Diseases, New York, NY, USA 3. JFK Memorial Hospital, Monrovia, Liberia. 4.Yale Antivirals & Vaccines Research Program, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT, USA; Despite how effective Pre-exposure prophylaxis (PrEP) is in preventing HIV, uptake among women in sub-Saharan …

Epidermal Differentiation Disorders Across The Lifespan: Growth, Ophthalmologic, And Perinatal Manifestations, Caroline Echeandia-Francis

Yale Medicine Thesis Digital Library

Epidermal differentiation disorders (EDDs) are a heterogeneous group of inherited skin diseases characterized by impaired epidermal barrier function, scaling, and erythema. Although substantial progress has been made in identifying the genetic causes of EDD, long-standing clinical observations—including impaired growth, ectropion, and increased rates of preterm birth—remain poorly characterized across genotypes. The prevalence, severity, and clinical significance of these manifestations have not been systematically evaluated in large, genotype-stratified cohorts, limiting the ability to provide anticipatory guidance and tailored clinical care. This thesis seeks to (1) characterize growth trajectories in children with EDD and determine genotype-specific patterns of growth impairment; (2) assess …

Prevalence Of K13 Mutant Malaria Parasites In Busia, Uganda, Ahmed Elzamzami

Yale Medicine Thesis Digital Library

Artemisinin derivatives form the backbone of all antimalarial combination therapies usedworld-wide. Resistance to this critical drug class is a growing problem in the highest malaria transmission regions of the world. First detected in southeast Asia, independent mutations conferring partial resistance to artemisinin’s have now emerged in East Africa.27, 32 Retrospectively, these mutations have been detected as early as 2016 in Uganda.36 Previous work by the Parikh lab highlights the efficacy of 3-day vs 5-day artemether-lumefantrine treatment regimen for uncomplicated malarial episodes in Busia, Uganda in 2019.41 Infections were followed and classified as recrudescent, a reinfection, SBP1 slow clearing, or an …

Repurposing Ezetimibe As A Therapeutic For Parkinson's Disease: Evaluating The Therapeutic Potential And Probing For A Mechanism, Brian Hilton

Yale Medicine Thesis Digital Library

Neurologic disease is the leading cause of disability globally and Parkinson’s disease (PD) has been the fastest growing neurologic brain disease over the last several decades. Despite the immense burden of PD on patients and society, there has yet to be an efficacious disease-modifying therapy. Investigation of candidate pharmaceuticals that have already been approved by the FDA for other conditions might provide an expedited path to the advent of disease-modifying therapy. There is a rich history of drug repurposing for symptomatic therapy for PD, with amantadine as the preeminent example. In order to identify candidate therapeutics for possible repurposing, an …

Rns-Based Early Prediction Of Antiseizure Medication Efficacy, Joshua Hobbs

Yale Medicine Thesis Digital Library

Drug-resistant focal epilepsy accounts for a significant portion of patients with epilepsy. These patients many times experience persistent seizures despite several ASM (anti-seizure medication) trials. RNS (Responsive neurostimulation) has demonstrated efficacy in reducing seizure frequency in patients that are resistant to drug trials, and provide continuous intracranial electroencephalographic monitoring. This longitudinal data may offer an opportunity to identify potential early biomarkers of ASM trial effectiveness, which could lead to quicker optimization of pharmacological therapy. This study in particular evaluated whether early changes in RNS-detection of seizure activity can predict a clinical response to ASMs in patients with drug-resistant focal epilepsy. …

Facial Harmony And Gender Congruence: Patient-Reported Outcomes Of Gender-Affirming Facial Surgery Using The Gender-Q And Gpsq, Helia Hosseini

Yale Medicine Thesis Digital Library

Background:Gender-affirming facial surgery (GAFS) addresses gender dysphoria by aligning facial features with gender identity, with historical emphasis on refining the upper facial third to render patients more attractive and feminine. The GENDER-Q, a novel patient-reported outcome measure (PROM), evaluates aesthetic, functional, and psychosocial outcomes, complementing the Gender Preoccupation and Stability Questionnaire (GPSQ) to assess effects of GAFS in this study. Methodology: Survey data from 86 patients was analyzed using GENDER-Q and GPSQ scores. Higher GENDER-Q scores indicated improved outcomes, whereas lower GPSQ scores reflected reduced gender dysphoria. Pre- and post-operative outcomes were compared using paired and unpaired t-tests. Spearman’s correlation …

A Spatial Transcriptomic Atlas And Cellular Lineage-Based Analysis Of Chondroblastoma, Will Jiang

Yale Medicine Thesis Digital Library

Chondroblastoma is a benign primary bone tumor with controversial cellular origin. Although bearing the name “chondroblastoma”, this musculoskeletal tumor has faced controversy as to whether chondroblasts are chondrocytes. Moreover, its cellular composition can make it difficult to distinguish amongst its mimics including giant cell tumor of bone, chondrosarcoma, and chondromyxoid fibromas.

This thesis aims to characterize the transcriptomic expression atlas of human chondroblastoma to better define the gene expression profile and diagnostic expression markers of chondroblastoma. Secondarily, this thesis aims to identify the lineage progression and cellular composition of chondroblastoma using spatial and temporal patterning analysis.

Histologically confirmed samples of …

Trends, Predictors, And Cerebrovascular Outcomes Of Vertebral Artery Injury In Cervical Fractures, Rahul Jayaram

Yale Medicine Thesis Digital Library

Background and Scientific Premise: Cervical spine trauma is a common emergencydepartment presentation, and vertebral artery injury (VAI) is a potentially occult but serious complication associated with posterior circulation stroke. Identification of patients at risk remains challenging due to subtle presentations, variable screening practices, and limited prior data. Research Aims: The aims of this study were to characterize temporal trends in VAI detection among adult patients presenting to the emergency department with cervical spine fractures between 2010 and 2022, identify independent demographic, clinical, and injury-related predictors of VAI, and evaluate the association between VAI and ischemic stroke within ninety days of …

Prevalence, Predictors, And Consequences Of Postoperative Dysphagia After Aortic Surgery, Andrew Joseph Johnson

Yale Medicine Thesis Digital Library

Prevalence, Predictors, and Consequences of Postoperative Dysphagia After Aortic SurgeryAndrew Johnson and Ronny Munoz-Acuna, M.D., Department of Anesthesiology, Yale School of Medicine, New Haven, CT 06510. Abstract Background: Postoperative dysphagia is an underrecognized complication following cardiothoracic surgery and is associated with aspiration, prolonged hospitalization, and adverse clinical outcomes. Patients undergoing complex aortic surgery may be at particularly high risk due to prolonged mechanical ventilation, extensive airway instrumentation, and neurologic vulnerability. Data describing the prevalence, predictors, and clinical consequences of postoperative dysphagia in this population remain limited. Research Aim: This study consisted of three aims: first, to determine the prevalence and …

Cross-Sectional Analysis Of The Hepatitis C Care Cascade Among People Who Use Drugs In New Haven, Ct, Thomas Shaifer Jones

Yale Medicine Thesis Digital Library

People who use drugs (PWUD) are at high risk of contracting Hepatitis C Virus (HCV) and often face significant barriers in accessing healthcare. Treatment of HCV is highly effective, but previous studies show low rates of successful treatment in practice due to multiple points of failure along the treatment cascade. Harm reduction and outreach programs such as syringe services programs (SSPs) and drug treatment programs including medication for opioid use disorder (MOUD) have emerged as possible points of leverage in advancing people through the cascade of care. To better understand how people who use drugs access HCV treatment and elucidate …

Tone Matters: Advancing Equity Through A Pilot Intervention To Increase Exposure Of Clinical Findings In Skin Of Color, Lamley Amanuah Lawson

Yale Medicine Thesis Digital Library

Background: The ability to accurately recognize cutaneous manifestations of disease is a foundational clinical skill. However, current undergraduate medical education heavily relies on lighter skin tone prototypes, leaving trainees underprepared to diagnose conditions in patients with melanin-rich skin.Research Aims: This study aimed to evaluate the efficacy of a brief, targeted, visually comparative digital intervention by measuring its impact on medical students' immediate diagnostic accuracy and self-reported clinical confidence in identifying dermatologic conditions across a diverse range of skin tones. Hypothesis: We hypothesized that a brief, targeted digital educational intervention featuring side-by-side visual comparisons of dermatologic conditions across a range of …

Frailty And Functional Decline After Elective Endovascular Abdominal Aortic Aneurysm Repair, Judy Li

Yale Medicine Thesis Digital Library

Background: Frailty can be used to estimate perioperative and long-term mortality risk in octogenarians undergoing elective endovascular abdominal aortic aneurysm repair (EVAR). Its association with functional decline, an important surrogate of quality of life in older adults, has not been well studied in this population. We aimed to evaluate whether preoperative factors such as frailty are associated with one-year functional decline after elective EVAR in octogenarians and to compare the performance of three different frailty assessments.

Methods: The Vascular Quality Initiative (VQI) database was queried for octogenarians who underwent elective EVAR for an asymptomatic infrarenal abdominal aortic aneurysm (AAA) (2014 …

Neurophysiologic Responses To Endovascular Interventions For Delayed Cerebral Ischemia Management, Rafael Seth Maarek

Yale Medicine Thesis Digital Library

Background/Scientific Premise: Delayed cerebral ischemia (DCI) continues to be a leading cause of poor outcomes in hospitalized aneurysmal subarachnoid hemorrhage (aSAH) patients. In addition to cerebral vasospasm, a growing constellation of pathophysiologic processes has been implicated in the development of DCI, including impaired autoregulation, micro-thrombosis, inflammation, and cortical spreading depolarizations. However, management options for patients showing signs of emerging DCI have largely remained spasmolytic in nature, and it remains unclear if reversing cerebral vasospasm in patients with signs of emerging DCI will reliably improve underlying neurophysiology. To our knowledge, no group has reliably shown postprocedural improvements in quantitative EEG metrics …