Search

The diffusion of passing over the saddle point of a three-dimensional quadric potential energy surface was studied by analytically solving a set of coupled generalized Langevin equations. An accurate expression of the passing probability was obtained. The effect of the coupling between different degrees of freedom which is represented by the off-diagonal elements of the inertia, friction and potential-curvature tensors was analyzed in detail. It is found that some of the coupling have great influence on the diffusion process, while others not. The combination of them results in an optimal injecting direction of the diffusing particles, revealing an optimal three-dimensional diffusion path. • Off-diagonal elements of the tensors in the generalized Langevin equation were all recovered. • Optimal path of diffusion on the three-dimensional potential energy surface was determined. • Two angles were defined to determine the optimal path of diffusion of Brownian particles. [ABSTRACT FROM AUTHOR]

Abstract Wound dressings with high flexibility, mechanical strength, and porosity have received increasing attention. Herein, nanocomposite sponges of sodium alginate/graphene oxide (GO)/polyvinyl alcohol were prepared by a freeze-thawing cyclic process and freeze-dried molding. The properties of the sponges were investigated including morphology, mechanical properties, swelling, water vapor permeability, in vitro norfloxacin (NFX) release, antibacterial property, and biocompatibility as well as in vivo wound healing in a mouse model. A GO concentration of 1 wt% resulted in the sponges with a homogeneously porous and interconnected network structure, which exhibited suitable water absorption, breathability, and mechanical properties. Hemolysis tests indicated that the prepared sponges were non-hemolytic material. The CCK-8 assay demonstrated that the presence of an appropriate amount of GO could promote the cell proliferation. The sponges displayed excellent bioavailability of NFX, with a sustained release behavior and a strong inhibitory effect against both Escherichia coli and Staphylococcus aureus. The in vivo evaluations demonstrated that the sponges enhanced wound healing. Therefore, these novel nanocomposite sponges are promising candidates for wound healing applications. Graphical abstract Image 1 Highlights • The sponges (SPG) were prepared by a freeze-thawing method and freeze-dried technology. • The SPG exhibited uniform pore structure and excellent flexibility. • Graphene oxide improved biocompatibility of the SPG. • The SPG could be used as an excellent wound dressing for biomedical field. [ABSTRACT FROM AUTHOR]