The wrinkle dynamics (such as reversibility and stability) of human skin are affected by the external stimuli, as well as the skin's structure and mechanical properties. Inspired by these tunable responses, three types of moisture-responsive wrinkle dynamics are achieved, for the first time, through a single film-substrate system. These dynamics include: (1) completely reversible wrinkles formation; (2) irreversible wrinkles formation I: the initially formed wrinkles can be permanently erased and never reappear; and (3) irreversible wrinkles formation II: once the wrinkles form, they can no longer be erased. The key to success is to control the stiffness and thickness ratios of the film and the substrate, and tailor the crosslink degree/gradient of the film to allow for moisture-dependent changes of modulus and swelling degree. These unique responsive dynamics motivate the invention of a series of optical devices triggered by moisture, including anticounterfeit tabs, encryption devices, water indicators, light diffusors, and antiglare films. This study also paves the road for further understanding of the skin wrinkling dynamics and manipulation.

Quantum states are described by wave functions whose phases cannot be directly measured, but which play a vital role in quantum effects such as interference and entanglement. The loss of the relative phase information, termed decoherence, arises from the interactions between a quantum system and its environment. Decoherence is perhaps the biggest obstacle on the path to reliable quantum computing. Here we show that decoherence occurs even in an isolated molecule although not all phase information is lost via a theoretical study of a central electron spin qubit interacting with nearby nuclear spins in prototypical magnetic molecules.The residual coherence, which is molecule-dependent, provides a microscopic rationalization for the nuclear spin diffusion barrier proposed to explain experiments. The contribution of

Flexible intelligent materials are desired to effectively regulate their own deformation and accurately sense their immediate morphology at the same time. Graphene foam is an attractive material for strain sensing and electrical/thermal performance control due to its outstanding mechanical, electrical, and thermal properties. However, graphene‐foam‐based materials with both strain sensing and deformation control capabilities are rarely reported. Here, a multiscale design of graphene foam with a single‐layer‐graphene‐dominated microstructure and resilient 3D network architecture, which leads to exceptional strain sensing performance as well as modulation ability of the electrical and thermal conductivity for shape memory polymers, is reported. The graphene foams exhibit a strain detection limit of 0.033%, a rapid response of 53 ms, long‐term stability over 10 000 cycles, significant thermoacoustic effect, and great heat‐generation and heat‐diffusion ability. By combining these advantages, an electro‐activated shape‐memory composite that is capable of monitoring its own shape state during its morphing process, is demonstrated.

In article number 1700828, Dianyun Zhang, Luyi Sun, and co-workers develop a series of moisture-responsive wrinkled-surface devices made using a poly(vinyl alcohol)-poly(dimethylsiloxane) bilayer system. These devices demonstrate reversible, temporary, or permanent wrinkles as moisturized, providing a route to tune the optical properties of a wrinkled surface for various applications, such as encryption devices, anticounterfeiting tabs, and water indicators. WRINKLING DEVICES

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