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The development of modern electronics has raised great demand for multifunctional materials to protect electronic instruments against electromagnetic interference (EMI) radiation and ice accretion in cold weather. However, it is still a great challenge to prepare high-performance multifunctional films with excellent flexibilty, mechanical strength, and durability. Here, we propose a layer-by-layer assembly of cellulose nanofiber (CNF)/Ti3C2Tx nanocomposites (TM) on a bacterial cellulose (BC) substrate via repeated spray coating. CNFs are hybridized with Ti3C2Tx nanoflakes to improve the mechanical properties of the functional coating layer and its adhesion with the BC substrate. The densely packed hierarchical structure and strong interfacial interactions endows the TM/BC films with good flexibility, ultrahigh mechanical strength (>250 MPa), and desirable toughness (>20 MJ cm-3). Furthermore, benefiting from the densely packed hierarchical structure, the resultant TM/BC films present outstanding EMI shielding effictiveness of 60 dB and efficient electro-/photothermal heating performance. Silicone encapsulation further imparts high hydrophobicity and exceptional durability against solutions and deformations to the multifunctional films. Impressively, the silicone-coated TM/BC film (Si-TM/BC) exhibits desirable low voltage-driven Joule heating and excellent photoresponsive heating performance, which demonstrates great feasibility for efficient thermal deicing under actual conditions. Therefore, we believe that the Si-TM/BC film with excellent mechanical properties and durability holds great promise for the practical applications of EMI shielding and ice accretion elimination.

In this study, we used murine chondrocytes as an in vitro model and mice exhibiting destabilization of the medial meniscus (DMM) as an in vivo model to investigate the mechanisms through which S-allyl cysteine (SAC) alleviates osteoarthritis (OA). SAC significantly reduced apoptosis and senescence and maintained homeostasis of extracellular matrix (ECM) metabolism in tert-butyl hydroperoxide (TBHP)-treated chondrocytes. Molecular docking analysis showed a -CDOCKER interaction energy value of 203.76 kcal/mol for interactions between SAC and nuclear factor erythroid 2-related factor 2 (Nrf2). SAC increased the nuclear translocation of Nrf2 and activated the Nrf2/HO1 signaling pathway in TBHP-treated chondrocytes. Furthermore, Nrf2 knockdown abrogated the antiapoptotic, antisenescence, and ECM regulatory effects of SAC in TBHP-treated chondrocytes. SAC treatment also significantly reduced cartilage ossification and erosion, joint-space narrowing, synovial thickening and hypercellularity in DMM model mice. Collectively, these findings show that SAC ameliorates OA pathology in TBHP-treated chondrocytes and DMM model mice by activating the Nrf2/HO1 signaling pathway.

Composite films containing different amounts of potassium sorbate (KS) were prepared by using fish scale collagen (Col) and polyvinyl alcohol (PVA). Fourier transform infrared spectroscopy (FTIR), light transmittance, mechanical, water vapor transmission rate (WVTR), and the antibacterial properties of the composite films were analyzed. The results showed that the addition of Col significantly reduced the light transmittance of the composite film, but KS had no significant effect on the light transmission. The tensile strength decreased first and then increased with the addition of KS, while the WVTR increased first and then decreased. The composite film exhibited a certain degree of antibacterial properties against E. coli and S. aureus. In addition, we found that ultrasonic treatment reduced the WVTR, and also improved tensile strength and elongation at break of the composite films, but had no significant effect on other properties. The KS/Col/PVA films have the potential to be used as antimicrobial food packaging.