Combined refraction and diffraction models for sea waves over complicated topography and with currents in shallow water

-Combined refraction and diffraction models in the form of linear parabolic approximation are derived through smallparameter method. More strictly theoretical basis and more accuracy in the models than Lozano's (1980) are obtained. Some theoretical defects in Liu's model (1985) with consideration of current are not only found but also eliminated. More strict and accurate models are, therefore, presented in this paper.The calculation results and analysis in applying the models to actual wave field with consideration of bottom friction will be given in the following paper.

Bilayered nanosheets used for complex topography wound anti‑infection

There is a consensus that the prevention of wound infection should be achieved in the following ways:(1)closing the wound to protect it from extra infection;(2)an antibacterial agent that could kill endogenous bacteria.However,existing bulk two-dimensional antibacterial materials show inefficient adhesion to wounds with complex morphology and thus cause the prevention of wound closure.Reducing the thickness of bulk two-dimensional materials to less than 100 nanometres endows them with great flexibility,which could allow them to adhere to wounds with complex morphology by only physical adhesion.Herein,a broad-spectrum and efficient antimicrobial peptide(AMP)was introduced to biocompatible methacrylated gelatine(GelMA)with multiple modification sites,which served as an inner antibacterial layer.After being combined with a biodegradable and good mechanical poly-l-lactide(PLLA)outer layer through plasma-treatment-assisted spin coating,we finally constructed bilayered antibacterial nanosheets with a thickness of approximately 80 nm.These bilayered nanosheets possess good adhesion to surfaces with complex topography and thus achieve better wound closure than other bulk two-dimensional materials.Moreover,this AMP-grafted conjugation shows minimal cytotoxicity compared with Ag^+antibacterial agents,and the antibacterial rate of nanosheets is dependent on the graft rate of AMP.We suggest that this bilayered antibacterial nanosheet might be an advanced anti-infection dressing for wound treatment in clinical settings.

THE SLOP FLUX METHOD FOR NUMERICAL BALANCE IN USING ROE'S APPROXIMATE RIEMANN SOLVER

Imbalance arises when the Roe＇s method is directly applied in the shallow water simulation.The reasons are different for the continuity equation and the momentum equations.Based on the Roe＇s method,a partial surface method is proposed for a perfect balance for the continuity equation.In order to generate a mathematically hyperbolic formulation,the momentum equations are split,which causes incompatibility in the calculation of the momentum equations.In this article a numerical approach named the Slop Flux Method（SFM）is proposed to balance the source terms and the flux gradient based on the finite volume method.The method is first applied to shallow water equations.The model is verified by analytical results of classical test cases with good agreement.Finally the method is applied to a steady flow simulation over a practical complicated topography and the result shows good balance and conservation.