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Some bi/multi‐stable mechanical meta‐structures are implemented as mechanical memory devices, which are with limits such as complex structural forms, low information storage capability and/or fragile structural stability to maintain the stored information bits robustly under external interferences. To address these issues, the structural intelligence is addressed by constructing a simple 3D‐printable multi‐layered cylindrical kirigami module with gradient structural parameters and a high‐efficiency mechanical memory device that can robustly store information bits exponentially larger than previous designs is proposed. The promising enhancement of information storage capability is demonstrated for the proposed mechanical memory device and relies on two mechanisms: 1) the deformation sequences of the kirigami module enabled by the gradient structural parameter, which brings the extra dimensional degree of freedom to break the traditional mechanical memory unit with only planar form and merits information bits with spatially combinatorial programmability, and 2) the combinatorics of the deformation independences among the cylindrical kirigami unit arrays in the constructed mechanical memory device. Particularly, both the structural stabilities and the desired structural robustness are achieved in the mechanical memory devices by additively introducing magnetic "N–S" poles in units, which can protect the stored information from interferences like mechanical crushing, impact, and/or vibration. [ABSTRACT FROM AUTHOR]

Antiadhesive hydrogels have been developed for preventing the formation of postoperative adhesions. However, it is challenging to design an injectable hydrogel with superior tissue retention properties that can be easily administered during minimally invasive surgical procedures to prevent the development of postsurgical adhesions. In this study, an injectable asymmetric‐adhesive hydrogel is fabricated using photocurable catechol‐grafted hyaluronic acid (HAD) for use during minimally invasive procedures to prevent the development of postoperative adhesions. The hydrogel exhibits superior tissue retention properties and favorably inhibits postoperative adhesion formation. This is the first time that an injectable hydrogel is designed via photocrosslinking to control asymmetric‐adhesive capability. The results show that laparoscopically delivered HAD precursor acts as a wet adhesive on the injured cecum, while its outward‐facing side is nonadherent after photocrosslinking. Intriguingly, the HAD acts as a physical barrier and polyanion trap to neutralize scavenger receptors, thereby inhibiting collagen deposition and uncontrolled recruitment of GATA6+ cavity macrophages. Furthermore, the HAD significantly downregulates the expression of fibrosis‐related and proinflammatory cytokines and promotes macrophage polarization. These results demonstrate that injection of the hydrogel can be readily integrated into laparoscopic surgery. Moreover, the HAD may be suitable for preventing adhesion formation after minimally invasive surgical procedures. [ABSTRACT FROM AUTHOR]