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Abstract Collecting gait data and providing haptic feedback are essential for the safety and efficiency of robot-based rehabilitation. However, readily available devices that can perform both are scarce. This work presents a novel method for mutual sensing and haptic feedback, through the development of an inflatable soft haptic sensor (ISHASE). The design, modeling, and characterization of ISHASE are discussed. Four ISHASEs are embedded in the insole of a shoe to measure ground reaction forces and provide haptic feedback. Four participants were recruited to evaluate the performance of ISHASE as a sensor and haptic device. Experimental results indicate that ISHASE can accurately estimate user’s ground reaction forces while walking, with a maximum and a minimum accuracy of 91% and 85%, respectively. Haptic feedback was delivered to four different locations under the foot, and users could identify the location with an average 92% accuracy. A case study that exemplifies a rehabilitation scenario is presented to demonstrate ISHASE’s usefulness for mutual sensing and haptic feedback. 

Abstract Uracil DNA-glycosylase (UNG) is a DNA repair enzyme that removes the highly mutagenic uracil lesion from DNA using a base flipping mechanism. Although this enzyme has evolved to remove uracil from diverse sequence contexts, UNG excision efficiency depends on DNA sequence. To provide the molecular basis for rationalizing UNG substrate preferences, we used time-resolved fluorescence spectroscopy, NMR imino proton exchange measurements, and molecular dynamics simulations to measure UNG specificity constants ( k cat / K M ) and DNA flexibilities for DNA substrates containing central AUT, TUA, AUA, and TUT motifs. Our study shows that UNG efficiency is dictated by the intrinsic deformability around the lesion, establishes a direct relationship between substrate flexibility modes and UNG efficiency, and shows that bases immediately adjacent to the uracil are allosterically coupled and have the greatest impact on substrate flexibility and UNG activity. The finding that substrate flexibility controls UNG efficiency is likely significant for other repair enzymes and has major implications for the understanding of mutation hotspot genesis, molecular evolution, and base editing.