Washington University Medical Center
Washington University St. Louis: Open ScholarshipNot a member yet
26344 research outputs found
Sort by
Partisan Realignment & The Evolution of Abortion Laws: Case Studies of Missouri and Florida
Get PDFThis thesis analyzes the relationship between partisan realignment and abortion policy in Missouri and Florida, demonstrating how the evolution of these laws reflects shifts in political identity, national party strategy, and state-level advocacy
Learning-based MRI Reconstruction Method with Coil Sensitivity Estimation and Prior Adaptation
Get PDFMagnetic Resonance Imaging (MRI) reconstruction from undersampled multi-coil k-space data is a challenging inverse problem, typically relying on fixed priors such as precom puted coil sensitivity maps. To improve adaptability, we propose a novel framework named Learning-based Coil sensitivity Estimation and Prior Adaptation (LCEPA). LCEPA formu lates reconstruction as a bilevel optimization, using a Joint Deep Equilibrium (Joint DEQ) model in the inner loop to simultaneously estimate images and coil sensitivity maps, while the outer loop adaptively fine-tunes image and coil priors using supervised data. Experiments demonstrate that LCEPA surpasses state-of-the-art methods in terms of PSNR and SSIM, showcasing robust generalization to varying acceleration rates and imaging modalities. Our approach thus provides an effective and flexible solution for accelerated MRI reconstruction in clinical scenarios
Development of A Bioelectronic Device for In Vitro Electrical Impedance Monitoring Using 3D Printed Conducting Hydrogel Scaffolds
No full textBioelectronic in vitro devices use electronics integrated with biology to monitor or influence cell behavior, with many methods using impedance to measure cell viability. By incorporating soft, 3-dimensional substrates into bioelectronics, we increase the relevancy of cell behavior by mimicking the in vivo environment. Previously, we have published a method for fabricating soft, tissue-like scaffolds by 3D printing a conducting polymer hydrogel, poly(3,4 - ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). Here, we present a novel method for anchoring these scaffolds into a fabricated device, enabling noninvasive electrical monitoring of cells growing on the scaffolds. The substrate, insulating material, adhesion method, and assembly were all optimized for ease of fabrication, electrical performance, and cytocompatibility. Characterization of the device reveals that the PEDOT:PSS structure reduces impedance and is stable for up to 56 days in solution. Studies in cell culture conditions suggest that the device\u27s impedance will stabilize after multiple days in media. Preliminary cell culture experiments provide proof of concept for the device’s use in drug screening for ovarian cancer. This report presents a customizable 3D cell sensing platform that can noninvasively monitor cell viability with future applications in personalized medicine using patient-derived cells
Constitutive Modeling of Uterine Wound Healing: Applications to Postpartum Involution and Surgical Scarring
No full textThe uterus undergoes major structural and mechanical changes after childbirth, especially during postpartum involution and following Cesarean delivery. However, the biomechanics of uterine healing remain poorly understood. This thesis focuses on characterizing the passive mechanical properties of murine uterine tissue across both natural postpartum recovery and surgical healing in the uterus. By using previously collected uniaxial and biaxial mechanical testing data, a two-fiber family plus neo-Hookean (2D 2FF + NH) constitutive model was applied to quantify changes in matrix stiffness, fiber alignment, and strain energy across various timepoints. Both mechanical testing data offered an extensive advantage to study these experimental setups, as they uncover the directional properties and physiological behavior of the murine uterine horns. This study establishes a mathematical foundation for futures studies on uterine wound healing and supports the development of diagnostic or therapeutic tools to improve proper uterine involution and recovery
Go Cry About It!
Get PDFI have always been a crier. I have always felt deeply and intensely. Goodbyes, heartbreak, joy, and empathy—I’m grateful to feel it all, even when it hurts. My artwork often investigates vulnerable topics through making the personal public using self archival and diaristic elements. Inspired by my familial and romantic relationships, I explore my connections to other people and how I memorialize and honor them. My painted works often depict ephemeral objects, establishing their value through the use of oil paints while my sculptures are often exaggerated, oversize forms, emphasizing the passage of time.
From January 1st to December 31st of 2024, I kept a record of every time I cried in a spreadsheet. My thesis explores the emotional release and absurdity of crying through the unpredictability of ceramics. Tracking emotions through cold, hard data negates the gravity of those feelings while contrasting them with bulbous, illustrative images of tears brings back the human touch. The subtle themes of grief—of people, relationships, and time itself—highlight the ways repressed emotions find their way out. The physicality of my thesis work specifically demands attention from the viewer by entering their space physically, screaming for someone to recognize the absurdity of such a display. I hope to inspire embracing vulnerability and appreciation of tears as a necessary bodily function required for emotional release as opposed to an embarrassment
Experimental Measurements of Compounds in Lithium-Air Battery Discharge Products
No full textLithium-air batteries have become increasingly popular due to their high theoretical energy density of 11,000 Wh/kg [1]. However, there are several challenges associated with lithium-air batteries. This project aims to gain a better understanding of the solid product produced from discharge of lithium-oxygen batteries by observing the lithium peroxide dependence on time spent discharging, time spent soaking for titration analyses, and cathode orientation. These experiments were performed using titration and UV-visible spectrophotometry. The lithium peroxide content was analyzed in cathodes with four different discharge times at the same current density. It was determined that there is a linearly increasing relationship between the discharge time and the mass of lithium peroxide; however, there is no significant relationship between the discharge time and the mass fraction of the experimental to theoretical mass of lithium peroxide. The dependence of lithium peroxide content on the soaking time in the titration solution was analyzed by comparing eight different soaking times on quarter cathodes. It was determined that there is no significant relationship between soaking time and mass fraction of lithium peroxide. The lithium peroxide dependence on cathode orientation – the coated side of the cathode facing towards the separator or away from the separator – was analyzed, and no significant relationship between cathode orientation and mass fraction was determined
Elastin and Endothelium’s Role in Aortic Contraction: A Wire Myography Study in Adult Mice
Get PDFThoracic aortic aneurysms (TAAs) are characterized by dilation and structural weakening of the aortic wall [1]. If left untreated, aortic dissections or life-threatening ruptures can occur. While current treatment options primarily involve minimally invasive surgical procedures, a deeper understanding of the underlying molecular and mechanical changes in the vessel wall could direct new forms of treatment. This report investigates the role of elastic fibers in the extracellular matrix (ECM) and the contribution of endothelial cells in maintaining aortic contractility. The overall goal is to observe how elastin degradation contributes to vessel dysfunction
Modeling Tendon Adaptation Under High-Intensity, Short-Duration Loads in Baseball Pitching
No full textBaseball pitching produces brief impulses of extremely high mechanical stress on the ulnar collateral ligament (UCL) and the surrounding flexor–pronator tendon complex. To quantify how these repeated loads influence tissue integrity, a high-level systems‑biology qualitative ODE model was developed that links mechanical stress, cumulative fatigue, viscoelastic relaxation, fibroblast activity, IL‑1β–mediated inflammation, and macrophage polarization to extracellular‑matrix (ECM) turnover. Using parameters derived from the literature and a representative workload of 100 pitches thrown over 2 hours, the model predicts (i) rapid ECM synthesis outpaces degradation in the early hours after a single outing, (ii) a transient peak in IL‑1β concentration (~2 × 10^-3 a.u.) after a moderate amount of time that coincides with a pro‑to‑anti‑inflammatory macrophage shift, and (iii) a saturation of cumulative fatigue after the first pitching session. These results highlight that recovery windows may be a dominant lever for maintaining tendon and ligament integrity, and they establish a qualitative foundation for real‑time workload management in pitchers
Integration of Sensors and Actuators in Mechanical Systems for Makerspace Applications
Get PDFThis independent study developed and implemented a workshop for the SLMP Makerspace that introduced microprocessors and actuators by guiding beginner makers through building a tilt- controlled marble maze using the Adafruit Circuit Playground Express (CPX). Participants learned to integrate the CPX’s onboard accelerometer with servo motors to control the maze’s movement, while gaining foundational skills in wiring and programming using Circuit Python or Arduino IDE. The workshop was designed to be accessible for those new to microprocessor integration, while still offering a meaningful introduction to core concepts in sensor-driven systems. It complements a Makerspace training module on Sensors and Actuators, currently in development, by reinforcing key concepts and ensuring that participants leave with both a solid understanding of the material and practical skills they can apply to their own projects. The training module will guide users toward more effective sensor and actuator selection, actuator control, implementation, and troubleshooting of common issues by providing detailed guidance using simple projects
Biology Department Publications: 2024
Get PDFThis document is a non-comprehensive list of publications made by graduate students, post-doctoral researchers, and faculty members in the Biology Department in 2024. It indexes those publications available through PubMed, and serves as an archival record of the Department\u27s robust scholarly contributions