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Abstract Transcatheter aortic valve replacement (TAVR) first received FDA approval for high-risk surgical patients in 2011 and has been approved for low-risk surgical patients since 2019. It is now the most common type of aortic valve replacement, and its use continues to accelerate. Computer modeling and simulation (CM&S) is a tool to aid in TAVR device design, regulatory approval, and indication in patient-specific care. This study introduces a computational fluid-structure interaction (FSI) model of TAVR with Medtronic’s CoreValve Evolut R device using the immersed finite element-difference (IFED) method. We perform dynamic simulations of crimping and deployment of the Evolut R, as well as device behavior across the cardiac cycle in a patient-specific aortic root anatomy reconstructed from computed tomography (CT) image data. These IFED simulations, which incorporate biomechanics models fit to experimental tensile test data, automatically capture the contact within the device and between the self-expanding stent and native anatomy. Further, we apply realistic driving and loading conditions based on clinical measurements of human ventricular and aortic pressures and flow rates to demonstrate that our Evolut R model supports a physiological diastolic pressure load and provides informative clinical performance predictions. 

Abstract This paper provides an overview of the new features of the finite element library deal.II, version 9.4. 

Abstract This paper provides an overview of the new features of the finite element library deal.II , version 9.5. 

Many studies have documented the impact of maker experiences on children's learning, but few have examined how caregivers participate in maker activities in museums, both as facilitators of their children's learning and as learners in their own right. This qualitative study involved observations and interviews with 88 caregivers participating in a range of making and tinkering activities at a science museum. Aspects of the physical setting (including the arrangement and familiarity of tools and materials) and social setting (including facilitators' interactions with children versus caregivers) influenced whether families participated and the roles that caregivers played (observing, facilitating, or making). Across these roles, caregivers described benefitting as learners -- by noticing their children's abilities and interests, learning new ways to support their children's learning, or fostering their own creativity. The results highlight strategies that museums can use to create inclusive maker activities that recognize caregivers' many roles and motivations during family visits. 

Reduced order models (ROMs) are computational models whose dimension is significantly lower than those obtained through classical numerical discretizations (e.g., finite element, finite difference, finite volume, or spectral methods). Thus, ROMs have been used to accelerate numerical simulations of many query problems, e.g., uncertainty quantification, control, and shape optimization. Projection-based ROMs have been particularly successful in the numerical simulation of fluid flows. In this brief survey, we summarize some recent ROM developments for the quasi-geostrophic equations (QGE) (also known as the barotropic vorticity equations), which are a simplified model for geophysical flows in which rotation plays a central role, such as wind-driven ocean circulation in mid-latitude ocean basins. Since the QGE represent a practical compromise between efficient numerical simulations of ocean flows and accurate representations of large scale ocean dynamics, these equations have often been used in the testing of new numerical methods for ocean flows. ROMs have also been tested on the QGE for various settings in order to understand their potential in efficient numerical simulations of ocean flows. In this paper, we survey the ROMs developed for the QGE in order to understand their potential in efficient numerical simulations of more complex ocean flows: We explain how classical numerical methods for the QGE are used to generate the ROM basis functions, we outline the main steps in the construction of projection-based ROMs (with a particular focus on the under-resolved regime, when the closure problem needs to be addressed), we illustrate the ROMs in the numerical simulation of the QGE for various settings, and we present several potential future research avenues in the ROM exploration of the QGE and more complex models of geophysical flows. 

This paper presents findings from a year-long after-school program that engages youth from local communities in computational making and community problem solving. Our goal is to understand how self-directed computational making activities contribute to shifts in students’ self-efficacy and perception of themselves as people who can pursue careers in STEM. During the first, skill-building semester, our preliminary findings suggest that when youth have the opportunity to work through self-directed projects, they engage in a variety of strategies to set goals and work through challenges. We believe that this work contributes to a growing field-wide understanding of novice designers’ problem scoping practices and their nuanced perceptions of challenge. 

Abstract This paper provides an overview of the new features of the finite element library deal.II, version 9.3.