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Most current JPEG steganalytic methods can only extract features from a series of linear residuals.Non-linear filters are not considered in these JPEG steganalytic methods, resulting in single types of residuals.Hence, a JPEG steganalytic method using non-linear residuals was proposed.Firstly, non-linear residuals were generated without a high computational cost by using element-wise minimum and maximum operations across a couple of linear residuals which had been obtained in the current JPEG steganalytic method.Secondly, according to the JPEG phase, the non-linear residual was divided into sub-residuals in which the histogram features were extracted.Thirdly, considering the minimum and maximum operators, the symmetrization method was accordingly designed.Finally, all the symmetrized histogram features were concatenated to form the final feature set.Experimental results indicate that the performance for JPEG steganalysis can be improved effectively by using both the linear and the non-linear residuals.

Renal artery stenosis (RAS) refers to the reduction of lumen diameter of one or both renal arteries, which can cause multiple systemic lesions such as renovascular hypertension, ischemic nephropathy and flash pulmonary oedema. RAS has been attached importance with the improvement of diagnostic level. However, there are still no precise treatments for RAS. As for revascularization, its effect on RAS needs to be evaluated further, and it is also a hot research area. We analyzed the causes and mechanisms regarding the suboptimal effect of renal artery revascularization in some studies, summarized the strategies and neoadjuvant therapies that recently used to improve the effect of renal artery revascularization, with highlights on the importance of selection of patients for the treatment, providing evidence for guiding renal artery revascularization, and for choosing directions in research on patient selection for the treatment and the improvement of treatment effectiveness.