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Machines made of soft materials bridge life sciences and engineering 1 . Advances in soft materials have led to skin-like sensors and muscle-like actuators for soft robots and wearable devices 1 – 3 . Flexible or stretchable counterparts of most key mechatronic components have been developed 4 , 5 , principally using fluidically driven systems 6 – 8 ; other reported mechanisms include electrostatic 9 – 12 , stimuli-responsive gels 13 , 14 and thermally responsive materials such as liquid metals 15 – 17 and shape-memory polymers 18 . Despite the widespread use of fluidic actuation, there have been few soft counterparts of pumps or compressors, limiting the portability and autonomy of soft machines 4 , 8 . Here we describe a class of soft-matter bidirectional pumps based on charge-injection electrohydrodynamics 19 . These solid-state pumps are flexible, stretchable, modular, scalable, quiet and rapid. By integrating the pump into a glove, we demonstrate wearable active thermal management. Embedding the pump in an inflatable structure produces a self-contained fluidic ‘muscle’. The stretchable pumps have potential uses in wearable laboratory-on-a-chip and microfluidic sensors, thermally active clothing and autonomous soft robots. A stretchable polymer pump that uses electric fields to accelerate ions in dielectric liquids can generate flow even when bent into different conformations, offering applications in soft robotics.

Electro-adhesion (EA) is a low-power, tunable, fast and reversible electrically-controlled adhesion method, effective on both conducting and insulating objects. Typically, only the electro-adhesive detachment force, i.e., the force required to separate an object from the EA patch, is measured. Here, we report a method that enables comparing the pre-contact EA attachment forces with post-contact EA detachment forces. We observe that pre-contact pressures are 1 to 100 times lower than post-contact detachment pressures, indicating the large role played by surface forces, charge injection, and polarization inertia. We characterize the time-dependence of pre- and post-contact EA forces as a function of the applied voltage waveform, observing that using an AC drive allowing for much faster release than DC operation. We measure both EA forces on conductive and insulating objects, using over 100 different EA patches covering a wide range of electrode dimensions. At 400 V, the EA release pressures for conductive objects range from 1 to 100 kPa, and are 1 to 10 times higher than pre-contact adhesion force. For dielectric objects, release pressures are 1 to 100 higher than pre-contact adhesion pressures. The methodology presented in this paper can enable standardized EA characterization while varying numerous parameters.

Force and strain sensors made of soft materials enable robots to interact intelligently with their surroundings. Capacitive sensing is widely adopted thanks to its low power consumption, fast response, and facile fabrication. Capacitive sensors are, however, susceptible to electromagnetic interference and proximity effects and thus require electrical shielding. Shielding has not been previously implemented in soft capacitive sensors due to the parasitic capacitance between the shield and sensing electrodes, which changes when the sensor is deformed. We address this crucial challenge by patterning the central sensing elastomer layer to control its compressibility. One design uses an ultrasoft silicone foam, and the other includes microchannels filled with liquid metal and air. The force resolution is sub-mN both in normal and shear directions, yet the sensor withstands large forces (>20 N), demonstrating a wide dynamic range. Performance is unaffected by nearby high DC and AC electric fields and even electric sparks. Capacitive soft force sensors require electrical shielding from electromagnetic interference, but this shielding can mess with the effectiveness of the sensing electrodes. Here, Aksoy et al. solve this problem by patterning the central sensing elastomer layer to control its compressibility.

Uncooled infrared detectors have enabled the rapid growth of thermal imaging applications. These detectors are predominantly bolometers, reading out a pixel’s temperature change due to infrared radiation as a resistance change. Another uncooled sensing method is to transduce the infrared radiation into the frequency shift of a mechanical resonator. We present here highly sensitive resonant infrared sensors, based on thermo-responsive shape memory polymers. By exploiting the phase-change polymer as transduction mechanism, our approach provides 2 orders of magnitude improvement of the temperature coefficient of frequency. Noise equivalent temperature difference of 22 mK in vacuum and 112 mK in air are obtained using f/2 optics. The noise equivalent temperature difference is further improved to 6 mK in vacuum by using high-Q silicon nitride membranes as substrates for the shape memory polymers. This high performance in air eliminates the need for vacuum packaging, paving a path towards flexible non-hermetically sealed infrared sensors. Though resonant infrared (IR) detectors are an attractive thermal imaging technology owing to its high performance potential, realizing devices with high sensitivity remains a challenge. Here, the authors report high-sensitivity resonant IR sensors based on thermo-responsive shape memory polymers.

Clothing with integrated high‐force actuators enables wearable haptics for immersive virtual reality (VR) and enables soft exoskeletons for rehabilitation or human augmentation. Electrostatic clutches (ESClutches) offer a very‐low‐energy solution to block motion and are mm thin. Challenges for ESClutches in wearables are 1) effective integration in clothing to accurately block body motion while ensuring comfort, 2) well‐controlled sliding for variable stiffness rendering, and 3) adaptation to shoulder or hip joints. Here, the control of sliding friction of soft ESClutches is demonstrated, using materials that enable both integration in textile and efficient force transfer to the user. We present a 1.3 mm‐thick soft glove with five ESClutches, providing up to 50 N of kinesthetic feedback per finger. A clutch in a thin haptic sleeve that controls elbow extension is reported. Eight cable‐format ESClutches on a shoulder are shown, selectively blocking multiple degrees of freedom. VR tests demonstrate that the glove and the sleeve give the user the ability to rank the softness and weight of virtual objects. In a teleoperation scenario, the glove enables the user to remotely feel an object's stiffness. The ESClutches and textile integration pave a path toward socially acceptable and comfortable kinesthetic haptics. Herein, clothing with integrated high‐force electrostatic clutches that enable wearable haptics for more immersive virtual reality (VR) and teleoperation is presented. Variable stiffness rendering, effective clothing integration, and hip joints’ adaptation challenges are presented. This enables to design haptic garments like a 30 g and 1.3 mm‐thick soft glove and a sleeve rendering variable stiffness and weights in VR.

Systematic investigations of the effects of mechano-electric coupling (MEC) on cellular cardiac electrophysiology lack experimental systems suitable to subject tissues to in-vivo like strain patterns while simultaneously reporting changes in electrical activation. Here, we describe a self-contained motor-less device (mechano-active multielectrode-array, MaMEA) that permits the assessment of impulse conduction along bioengineered strands of cardiac tissue in response to dynamic strain cycles. The device is based on polydimethylsiloxane (PDMS) cell culture substrates patterned with dielectric actuators (DEAs) and compliant gold ion-implanted extracellular electrodes. The DEAs induce uniaxial stretch and compression in defined regions of the PDMS substrate at selectable amplitudes and with rates up to 18 s −1 . Conduction along cardiomyocyte strands was found to depend linearly on static strain according to cable theory while, unexpectedly, being completely independent on strain rates. Parallel operation of multiple MaMEAs provides for systematic high-throughput investigations of MEC during spatially patterned mechanical perturbations mimicking in-vivo conditions. While strain is known to affect cardiac electrophysiology, experimental systems to interrogate the effect of rapid strain cycles on cardiac tissue are lacking. Here the authors introduce a multielectrode array that can induce rapid dynamic strain cycles on cardiomyocyte strands and see effects of strain amplitude but not strain rate on impulse conduction.

•  Introduction •  Telomerase inhibitors •  Telomerase activators •  Conclusions and perspectives Telomeres serve the dual function of protecting chromosomes from genomic instability as well as protecting the ends of chromosomes from DNA damage machinery. The enzyme responsible for telomere maintenance is telomerase, an enzyme capable of reverse transcription. Telomerase activity is typically limited to specific cell types. However, telomerase activation in somatic cells serves as a key step toward cell immortalization and cancer. Targeting telomerase serves as a potential cancer treatment with significant therapeutic benefits. Beyond targeting cancers by inhibiting telomerase, manipulating the regulation of telomerase may also provide therapeutic benefit to other ailments, such as those related to aging. This review will introduce human telomeres and telomerase and discuss pharmacological regulation of telomerase, including telomerase inhibitors and activators, and their use in human diseases.

Electrowetting on dielectric (EWOD) allows rapid movement of liquid droplets on a smooth surface, with applications ranging from lab‐on‐chip devices to micro‐actuators. The in‐plane force on a droplet is a key indicator of EWOD performance. This force has been extensively modeled but few direct experimental measurements are reported. We study the EWOD force on a droplet using two setups that allow, for the first time, the simultaneous measurement of force and contact angle, while imaging the droplet shape at 6000 frames/s. For several liquids and surfaces, we observe that the force saturates at a voltage of approximately 150 V. Application of voltages of up 2 kV, that is, 10 times higher than is typical, does not significantly increase forces beyond the saturation point. However, we observe that the transient dynamics, localized at the front contact line, do not show saturation with voltage. At the higher voltages, the initial front contact line speed continues to increase, the front contact angle temporarily becomes near zero, creating a thin liquid film, and capillary waves form at the liquid–air interface. When the localized EWOD forces at the contact line exceed the capillary forces, projectile droplets form. Increasing surface tension allows for higher droplet forces, which we demonstrate with mercury. We investigate electrowetting on dielectric actuation, force saturation, contact angle saturation, and dynamics using two experimental setups. The setups measure the droplet force and contact angles simultaneously and apply high voltages of up to 2000 V.

A multimaterial inkjet printing method for integrated soft multifunctional machines is reported, combining dense arrays of electrostatic actuators, multilayer electrical routing, and complex networks of microfluidic channels in one printing process. Most additive manufacturing methods for soft robots are developed for devices driven by external fluidic pressure sources and are not suited to fabricate soft electrically driven actuators. To integrate electrostatic zipping actuators and microfluidics in stretchable soft machines without any rigid components, inks for sacrificial layers, dielectric elastomers, and compliant electrodes are developed herein, along with a unified printing process to print multilayer structures. Printed 2.5D stacks are transformed into fully functional 3D soft machines by inflating thin elastomer channels. Two demonstrators are reported, each consisting of seven printed layers: a flexible peristaltic pump and a compliant slug drive, inspired by the locomotion of slugs. The peristaltic pump has six integrated actuators, whereas the slug drive has 28 integrated actuators, generating a travelling wave used to transport objects. These soft devices demonstrate how inkjet printing produces densely packed high‐voltage actuators, including vias for electrical routing. Sensors and logic may be printed in the future to produce more complex autonomous soft machines. A multimaterial inkjet printing method for integrated soft multifunctional machines is reported, integrating densely packed electrostatic zipping actuators and microfluidics into stretchable machines. Two stretchable demonstrators are shown: a flexible peristaltic pump, with six integrated actuators, and a slug drive, inspired by the locomotion of slugs, with 28 integrated actuators generating a travelling wave.

We present a mechanically active cell culture substrate that produces complex strain patterns and generates extremely high strain rates. The transparent miniaturized cell stretcher is compatible with live cell microscopy and provides a very compact and portable alternative to other systems. A cell monolayer is cultured on a dielectric elastomer actuator (DEA) made of a 30 μm thick silicone membrane sandwiched between stretchable electrodes. A potential difference of several kV’s is applied across the electrodes to generate electrostatic forces and induce mechanical deformation of the silicone membrane. The DEA cell stretcher we present here applies up to 38% tensile and 12% compressive strain, while allowing real-time live cell imaging. It reaches the set strain in well under 1 ms and generates strain rates as high as 870 s −1 , or 87%/ms. With the unique capability to stretch and compress cells, our ultra-fast device can reproduce the rich mechanical environment experienced by cells in normal physiological conditions, as well as in extreme conditions such as blunt force trauma. This new tool will help solving lingering questions in the field of mechanobiology, including the strain-rate dependence of axonal injury and the role of mechanics in actin stress fiber kinetics.