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Abstract Point defects typically reduce the thermal conductivity (κ) of a crystal due to increased scattering of heat‐carrying phonons, a mechanism that is well understood and widely used to enhance or impede heat transfer in the material for different applications. Here an opposite effect is reported where the introduction of point defects in graphite with energetic particle irradiation increases its cross‐planeκby nearly a factor of two, from 10.8 to 18.9 W m K⁻¹at room temperature. Integrated differential phase contrast imaging with scanning transmission electron microscopy revealed the creation of spiro interstitials in graphite by the irradiation. The enhancement inκis attributed to a remarkable mechanism that works to the benefit of phonon propagation in both the harmonic and anharmonic terms: these spiro interstitial defects covalently bridge neighboring basal planes, simultaneously enhancing acoustic phonon group velocity and reducing phonon–phonon scattering in the graphite structure. The enhancement ofκreveals an unconventional role of lattice defects in heat conduction, i.e., easing the propagation of heat‐carrying phonons rather than impeding them in layered materials, inspiring their applications for thermal management in heavily radiative environments. 

Grasping a simple object from the side is easy --- unless the object is almost as big as the hand or space constraints require positioning the robot hand awkwardly with respect to the object. We show that humans --- when faced with this challenge --- adopt coordinated finger movements which enable them to successfully grasp objects even from these awkward poses. We also show that it is relatively straight forward to implement these strategies autonomously. Our human-studies approach asks participants to perform grasping task by either ``puppetteering'' a robotic manipulator that is identical~(geometrically and kinematically) to a popular underactuated robotic manipulator~(the Barrett hand), or using sliders to control the original Barrett hand. Unlike previous studies, this enables us to directly capture and compare human manipulation strategies with robotic ones. Our observation is that, while humans employ underactuation, how they use it is fundamentally different (and more effective) than that found in existing hardware. 

Bistable electroactive polymers (BSEP) combine shape memory with large-strain actuation at the rubbery state to achieve rigid-to-rigid actuation. The stiffness of the BSEP is tunable via glass transition or phase changing. The reversible melting-crystallization of the polymer chains in the phase changing BSEP contributes to the stiffness change within a narrow temperature range. A modulus change of more than 1000 folds can be achieved within 3 °C. Additionally, large actuation strains rivaling those of VHB acrylic elastomers can be obtained at the rubbery state. Explorations regarding potential applications of this material have been focused on tactile displays. In one design, Joule heating of a serpentine-shaped compliant electrode coated on a BSEP film, coupled with a pneumatic pressure source has been employed to raise diaphragm dots with 1.5 mm base diameter to heights up to 0.7 mm. The resulting Braille electronic readers could thus be actuated with low voltages. 

Artificial smart skins that integrate sensing and adaptiveness present a novel platform in wearable electronics on epidermis or next‐generation robotics. Herein, a highly sensitive capacitive touch senor based on a self‐conformable bi‐stable electroactive polymer (BSEP) is developed. The device combines the properties of conformable polymers and touch sensors, which grants the sensor the ability to conform to the shape of various surfaces and in different working conditions. A spray‐coated silver nanowire (AgNW) is selected as the sensor electrode for high‐resolution patterning. The unique antenna‐shaped electrode pattern results in a capacitance change of 31% when in contact with ground at a baseline of 0.13 pF. The BSEP provides stiffness tunability via an embedded compliant heater. The heater combines interdigitated silver with carbon nanotubes delivering uniform and highly efficient heating to create a tunable device with stiffness between 100s of MPa and tens of kPa, providing a large working flexibility. The efficient resistive heater provides uniform and stable heating over an area of 40 by 40 mm with a rate of 48 °C min⁻¹at an input voltage as low as 7 V. This research merges intelligent polymeric systems and thin film electronics advancing conformable, skin‐like functional electronics. 

We report the results of the COVID Moonshot, a fully open-science, crowdsourced, and structure-enabled drug discovery campaign targeting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease. We discovered a noncovalent, nonpeptidic inhibitor scaffold with lead-like properties that is differentiated from current main protease inhibitors. Our approach leveraged crowdsourcing, machine learning, exascale molecular simulations, and high-throughput structural biology and chemistry. We generated a detailed map of the structural plasticity of the SARS-CoV-2 main protease, extensive structure-activity relationships for multiple chemotypes, and a wealth of biochemical activity data. All compound designs (>18,000 designs), crystallographic data (>490 ligand-bound x-ray structures), assay data (>10,000 measurements), and synthesized molecules (>2400 compounds) for this campaign were shared rapidly and openly, creating a rich, open, and intellectual property–free knowledge base for future anticoronavirus drug discovery.