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Balancing the exceptional mechanical strength and repair efficiency of self-healing materials presents a significant challenge to unlocking their full potential in practical applications. Inspired by natural spider silk and cartilage, multiple dynamic hydrogen bonds were introduced into the pre-prepared polyurethane (PU). Then modifided graphene oxide (GO) nanosheets with dynamic hydrogen bonds were added into the prepared PU to form composites (AU-PU/GDU) to establish a dense hydrogen bond network structure, providing strong interfacial interactions. The AU-PU/GDU film exhibits excellent tensile strength (39.6 MPa), high elongation at break (1155.6 %), and outstanding repair efficiency (90.3 %). Using AU-PU/GDU as the flexible base, a superhydrophobic conductive composite coating (F-AU-PU/GDU) with a contact angle greater than 150° was prepared by incorporating superhydrophobic nanomaterials. This work lays the foundation for the development of multifunctional materials through the creation of self-healing superhydrophobic conductive composite coatings, which have a wide range of potential applications. Functionalized graphene oxide forms a coating on a flexible, self-repairing polyurethane film, resulting in the composite film with super-strong strength, toughness, high extensibility, conductivity, and superhydrophobicity. After damage, the composite film undergoes repair with minimal impact on its electrical conductivity and superhydrophobic properties. [Display omitted] • Self-healing polyurethane composites with a hierarchical hydrogen bonding structure was successfully prepared. • The surface of polyurethane coated with modified nanoparticles showing superhydrophobicity and electrical conductivity. • The composite film has excellent tensile strength, high stretchability. [ABSTRACT FROM AUTHOR]

• Fe 3 O 4 nanoparticles were successfully deposited in situ on the pore wall of 3D enhanced graphene aerogel. • The aerogel has strong compression properties. • The aerogel has good microwave absorption performance with the minimum reflection loss -58.13 dB. Graphene aerogels with three-dimensional (3D) hierarchical porous structures have attracted considerable attention as absorptive materials. Here, an enhanced 3D graphene oxide/carbon nanotube/epoxy resin aerogel (GCEA) was used as a template to successfully deposit Fe 3 O 4 nanoparticles on the pore walls through in-situ chemical precipitation, resulting in a 3D composite aerogel absorber (rGCEA@Fe 3 O 4) with both dielectric and magnetic loss properties. The rGCEA@Fe 3 O 4 possesses excellent structural stability, conductive network, and evenly distributed magnetic particles. The rGCEA@Fe 3 O 4 showed excellent electromagnetic wave (EMW) absorption performance, with the minimum reflection loss (RL) reaching -58.13 dB at a frequency of 12.08 GHz and a thickness of 2.5 mm. The effective bandwidth was maximized at 6.64 GHz when the thickness was 2.2 mm. The aerogel prepared in this study can be directly used as encapsulation and absorptive materials for precision instruments. This work provides a new approach for the development of 3D hierarchical absorptive composite materials. Fe 3 O 4 nanoparticles are deposited onto the pore wall of graphene aerogel through in-situ chemical precipitation method. Multiple heterogeneous interfaces are formed among graphene, CNTs and Fe 3 O 4 , leading to the occurrence of both dipole polarization and interface polarization phenomena. The prepared composite aerogel exhibits excellent dielectric and magnetic loss properties, demonstrating outstanding absorption performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Background Astragalus membranaceus has been clinically used in cerebral ischemia treatment in China and its main component, Astragaloside IV (Ast IV) shows anti-hypoxia activity, but the underlying mechanism has not been clearly clarified. This study was aimed to investigate the effects of Ast IV on hypoxia-induced injury in PC-12 cells as well as the underlying mechanism. Methods Relative miR-124 expression was detected by qRT-PCR. Hic-5 expression was analyzed by qRT-PCR and Western blot. To alter miR-124 and Hic-5 expressions, cells were respectively transfected with miR-124 mimic and pEX-Hic-5. Cell proliferation and apoptosis were measured by BrdU assay and Annexin V-fluorescein isothiocynate (FITC)/propidium iodide (PI) double staining method, respectively. Besides, apoptotic proteins and cell proliferation-associated factors were analyzed by Western blot. Results Ast IV alleviated hypoxia-induced injury in PC-12 cells by decreasing apoptosis ( P  <  0.01). Ast IV inhibited up-regulation of miR-124 induced by hypoxia ( P  <  0.01). miR-124 mimic impaired the anti-apoptotic effect of Ast IV on PC-12 cells ( P  <  0.01). Hic-5 expression was significantly down-regulated in miR-124 overexpressed cells ( P  <  0.001) and Hic-5 overexpression activated Sp1/Survivin signaling pathway ( P  <  0.001). Conclusion Ast IV could ameliorate hypoxia-induced injury in PC-12 cells by decreasing miR-124 expression and then up-regulating Hic-5 expression. [ABSTRACT FROM AUTHOR]