EFFECTS OF VARYING BOTTOM ON NONLINEAR SURFACE WAVES

The resonant flow of an incompressible, inviscid fluid with surface tension on varying bottoms was researched. The effects of different bottoms on the nonlinear surface waves were analyzed. The waterfall plots of the wave were drawn with Matlab according to the numerical simulation of the fKdV equation with the pseudo-spectral method. From the waterfall plots, the results are obtained as follows： for the convex bottom, the waves system can be viewed as a combination of the effects of forward-step forcing and backwardstep forcing, and these two wave systems respectively radiate upstream and downstream without mutual interaction. Nevertheless, the result for the concave bottom is contrary to the convex one. For some combined bottoms, the wave systems can be considered as the combination of positive forcing and negative forcing.

Objective response rate assessment in oncology: Current situation and future expectations

The tumor objective response rate(ORR)is an important parameter to demonstrate the efficacy of a treatment in oncology.The ORR is valuable for clinical decision making in routine practice and a significant end-point for reporting the results of clinical trials.World Health Organization and Response Evaluation Criteria in Solid Tumors(RECIST)are anatomic response criteria developed mainly for cytotoxic chemotherapy.These criteria are based on the visual assessment of tumor size in morphological images provided by computed tomography(CT)or magnetic resonance imaging.Anatomic response criteria may not be optimal for biologic agents,some disease sites,and some regional therapies.Consequently,modifications of RECIST,Choi criteria and Morphologic response criteria were developed based on the concept of the evaluation of viable tumors.Despite its limitations,RECIST v1.1 is validated in prospective studies,is widely accepted by regulatory agencies and has recently shown good performance for targeted cancer agents.Finally,some alternatives of RECIST were developed as immune-specific response criteria for checkpoint inhibitors.Immune RECIST criteria are based essentially on defining true progressive disease after a confirmatory imaging.Some graphical methods may be useful to show longitudinal change in the tumor burden over time.Tumor tissue is a tridimensional heterogenous mass,and tumor shrinkage is not always symmetrical;thus,metabolic response assessments using positron emission tomography(PET)or PET/CT may reflect the viability of cancer cells or functional changes evolving after anticancer treatments.The metabolic response can show the benefit of a treatment earlier than anatomic shrinkage,possibly preventing delays in drug approval.Computer-assisted automated volumetric assessments,quantitative multimodality imaging in radiology,new tracers in nuclear medicine and finally artificial intelligence have great potential in future evaluations.

Generation of Solitary Rossby Waves by Unstable Topography

The effect of topography on generation of the solitary Rossby waves is researched. Here, the topography, as a forcing for waves generation, is taken as a function of longitude variable x and time variable t, which is called unstable topography. With the help of a perturbation expansion method, a forced mKdv equation governing the evolution of amplitude of the solitary Rossby waves is derived from quasi-geostrophic vortieity equation and is solved by the pseudo-spectral method. Basing on the waterfall plots, the generational features of the solitary Rossby waves under the influence of unstable topography and stable topography are compared and some conclusions are obtained.