Soft gels with spatially defined mesoscale distributions of chemical activity that guide and accelerate reactions by chemical nanoconfinement are found ubiquitously in nature but are rare in artificial systems. In this study, we introduce chemically nanostructured bulk organogels with periodically ordered morphologies from self-assembled block copolymer monoliths with a single selectively cross-linked block (xBCP). Ordered bulk organogels are fabricated with various distinct morphologies including hexagonally packed cylinders and two gyroidal three-dimensionally periodic network structures that exhibit macroscopic and nanoscopic structural integrity upon swelling.
View Article and Find Full Text PDFWearable robots are emerging as a viable and effective solution for assisting and enabling people who suffer from balance and mobility disorders. Virtual prototyping is a powerful tool to design robots, preventing the costly iterative physical prototyping and testing. Design of wearable robots through modelling, however, often involves computationally expensive and error-prone multi-body simulations wrapped in an optimization framework to simulate human-robot-environment interactions.
View Article and Find Full Text PDFObstructions influence the growth and expansion of bodies in a wide range of settings-but isolating and understanding their impact can be difficult in complex environments. Here, we study obstructed growth/expansion in a model system accessible to experiments, simulations, and theory: hydrogels swelling around fixed cylindrical obstacles with varying geometries. When the obstacles are large and widely-spaced, hydrogels swell around them and remain intact.
View Article and Find Full Text PDFConventional trajectory planning for lower limb assistive devices usually relies on a finite-state strategy, which pre-defines fixed trajectory types for specific gait events and activities. The advancement of deep learning enables walking assistive devices to better adapt to varied terrains for diverse users by learning movement patterns from gait data. Using a self-attention mechanism, a temporal deep learning model is developed in this study to continuously generate lower limb joint angle trajectories for an ankle and knee across various activities.
View Article and Find Full Text PDFCurrent guidelines recommend that individuals with moderate COVID-19 disease isolate for 5 days after the first appearance of symptoms or a positive SARS-CoV-2 test. It would be useful to understand the time course of infectious virus production and its correlation with virus detection using a rapid antigen test (RAT) or quantitative reverse transcriptase (qRT)-PCR. In a phase 2 study, 242 vaccinated patients with COVID-19 and at low risk for progression to severe disease initiated 5 days of treatment with pomotrelvir (PBI-0451, a SARS-CoV-2 main protease inhibitor) or placebo within 5 days after symptom onset.
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