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Microorganism invasion is still a severe threat for wound healing, which usually induces severe complications and cannot be eradicated completely. Thus, a biodegradable nanomaterial for guarding against bacteria-associated wound infection and accelerating wound healing is of vital importance. Here, black phosphorus nanosheets (BPs) were successfully decorated with cationic carbon dots (CDs) through an in situ growth strategy. The BPs@CDs exhibit photon-responsiveness and contact-responsiveness as an antibacterial agent, which shorten wound healing time. Moreover, the BPs@CDs show available photothermal and photodynamic therapy via exploring their photothermal properties and the ability of singlet-oxygen (1O2) production. Astonishingly, the BPs@CDs could possess antibacterial activity even without laser illumination due to an electrostatic attraction between bacteria and cationic CDs on the surface of BPs. This chemical therapy causes the antibacterial process to occur more accurately and for a faster 1O2 release to kill bacteria than in a normal process. Importantly, BPs@CDs display outstanding cytocompatibility and hemocompatibility. In vitro and in vivo investigations demonstrate that the BPs@CDs have enhanced antibacterial effect and can significantly accelerate skin tissue regeneration and wound closure. Given their antibacterial triple-combination therapy and excellent physicochemical properties, the broad application of BPs@CDs in bacteria-associated wound management is anticipated. [ABSTRACT FROM AUTHOR]

This paper describes the influence on the compressive and dissipative behavior of entangled metallic wire material (EMWM) samples provided by their size and mutual connectivity. The mechanical properties of EMWM specimens with different thicknesses are obtained from quasi-static compressive and cyclic loading. The behavior of the stress-strain curves, tangent modulus, and loss factor are strongly dependent on the thickness of the samples. The analysis from samples connected in different layouts shows that apart from the global thickness, size scale effects and contact interface also play important roles in controlling the behavior of EMWM systems. The importance of the sample size and its connectivity with adjacent different layers are defined by the unique microstructure and contact properties of the wires near the specimen boundary layer. The boundary layer produces different mechanical behaviors and a distinct structural configuration compared to the EMWM bulk solid. These peculiar characteristics are confirmed by microstructural and qualitative observations obtained from computed tomography scanning. The results and analysis presented in this work are relevant to designing EMWM material systems with adaptive performance under different loading and geometric constraints. [ABSTRACT FROM AUTHOR]