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Abstract To overcome the spatial resolution limit set by aperture-limited diffraction in traditional scanning transmission electron microscopy, microscopists have developed ptychography enabled by iterative phase retrieval algorithms and high-dynamic-range pixel array detectors. Current detector designs are limited by the data rate off chip, so a high-pixel-count detector has a proportionally lower frame rate than the few-segment detectors used for differential phase contrast (DPC) imaging. This slower acquisition speed leads to heightened vulnerability to scan noise, drift, and potential sample damage. This creates opportunities for repurposing fast segmented detectors for ptychography by trading a reduction in reciprocal space pixels for an increase in real space pixels. Here, we explore a strategy of oversampling in real space and instead apply detector pixel upsampling during the reconstruction process. We demonstrate the viability of achieving super-resolution ptychography on thin objects using only 2 × 2 detector pixels, surpassing the resolution of integrated DPC (iDPC) imaging. With optimization using simulated datasets and experiments on MoTe2/WSe2 bilayer moiré superlattices, we achieved super-resolution ptychography reconstructions under rapid acquisition conditions (37.5 pA, 1 μs dwell time), yielding over 50% improvements in contrast and information limit compared to annular dark field and iDPC imaging on the same detectors. 

Institutional support is crucial for the successful career advancement of all faculty but in particular those who are women. Evolving from the past, in which gender disparities were prevalent in many institutions, recent decades have witnessed significant progress in supporting the career advancement of women faculty in science and academic medicine. However, continued advancement is necessary as previously unrecognized needs and new opportunities for improvement emerge. To identify the needs, opportunities, and potential challenges encountered by women faculty, the Women’s Leadership Committee of the Arteriosclerosis, Thrombosis, and Vascular Biology Council developed an initiative termed GROWTH (Generating Resources and Opportunities for Women in Technology and Health). The committee designed a survey questionnaire and interviewed 19 leaders with roles and responsibilities in faculty development from a total of 12 institutions across various regions of the United States. The results were compiled, analyzed, and discussed. Based on our interviews and analyses, we present the current status of these representative institutions in supporting faculty development, highlighting efforts specific to women faculty. Through the experiences, insights, and vision of these leaders, we identified success stories, challenges, and future priorities. Our article provides a primer and a snapshot of institutional efforts to support the advancement of women faculty. Importantly, this article can serve as a reference and resource for academic entities seeking ideas to gauge their commitment level to women faculty and to implement new initiatives. Additionally, this article can provide guidance and strategies for women faculty as they seek support and resources from their current or prospective institutions when pursuing new career opportunities. 

This book develops limit theorems for a natural class of long range random walks on finitely generated torsion free nilpotent groups. The limits in these limit theorems are Lévy processes on some simply connected nilpotent Lie groups. Both the limit Lévy process and the limit Lie group carrying this process are determined by and depend on the law of the original random walk. The book offers the first systematic study of such limit theorems involving stable-like random walks and stable limit Lévy processes in the context of (non-commutative) nilpotent groups.