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Hong-Peng Chen,1,2,* Xiao-Yan Wang,1,* Xiao-Yan Pan,1 Wang-Wang Hu,1 Shu-Ting Cai,1 Kiran Joshi,3 Lie-Hua Deng,1,2 Daqing Ma3 1Department of Critical Care Medicine, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, People’s Republic of China; 2Zhanjiang Key Laboratory of Organ Injury and Protection and Translational Medicine, Zhanjiang, Guangdong, People’s Republic of China; 3Division of Anesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital, London, UK*These authors contributed equally to this workCorrespondence: Lie-Hua Deng; Daqing MaDepartment of Critical Care Medicine, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, ChinaEmail glinson@126.com; d.ma@imperial.ac.ukIntroduction: Because of its high morbidity and mortality, sepsis remains the leading cause of death in the ICU. Microparticles (MP) have been largely studied as potential diagnostic or prognostic markers in various diseases including sepsis.Objective: The biological and clinical relevance of neutrophil-derived microparticles (NDMPs) within the MP population remains unclear. The objective of this study was to elucidate the relationship between plasma NDMPs and the prognosis of patients with sepsis and/or septic shock.Methods: The study was designed as an observational, noninterventional clinical study. The cohort for this study included 40 sepsis and 40 septic shock patients together with 10 healthy controls admitted to the Intensive Care Unit (ICU) and the Health Surveillance Center in the Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China, from January to November 2018, respectively. The degree of critical disease for sepsis and septic shock was evaluated, with data analyses conducted from 2018 to 2019.Results: On days 1, 3 and 5 post-admission a series of data including plasma NDMP levels, patient demographics, TNF-α levels, IL-6 levels, sTREM-1 levels, and the sepsis severity score measurements were collected. A survival curve was plotted against levels of plasma NDMPs. Levels of NDMPs were observed to be higher in the septic shock patients than in the sepsis patients on days 1, 3, and 5 post-ICU admission (p < 0.05). NDMP levels were significantly increased in sepsis and septic shock patients with a parallel increase in pro-inflammatory mediators and sepsis severity score (p < 0.05) as well as mortality.Conclusion: Our data suggest that NDMPs may be a biomarker of sepsis severity and mortality although its implications on sepsis prognosis warrant further study.Keywords: sepsis, septic shock, cell-derived microparticles, biomarker, prognosis

A novel smoothing method based on control vector parameterization technique for solving nonlinear optimal control problems with inequality constraints is developed in this paper. The proposed algorithm discretizes the original nonlinear optimal control problem by using parametization quadratic penalty function and smoothing function. The nonlinear optimal control problems with inequality path constraints can be converted into vector parameterization by adjusting penalty factors. The equivalence of the transformation for optimal control problem with inequality path constraints is proved. The theorems show the proposed smoothing method for nonlinear optimal control problems is effective.

A new spectral method based on Galerkin approximation solutions of the nonlinear optimal control systems is proposed in this paper. Galerkin approximation with Chebyshev polynomials (GACP) is firstly used to solve the generalized Hamilton-Jacobi-Bellman (GHJB) equation for the nonlinear optimal control systems. The proposed GACP method employs some Chebyshev global polynomials as the trial functions for discretization of GHJB equation on a well-defined region of attraction. A stable optimal solution of a nonlinear control system is finally obtained. Numerical example shows that the proposed method can efficiently solve the nonlinear optimal control problem and therefore is promising.

Controlling the GOP (group of picture) size in distributed video coding is an important task since it has significant impact on the video coding performance. This paper presents a method to control the GOP size in the distributed video coding based on the Distortion-Quantization optimal and frame activity. To perform GOP size control adaptively, firstly this work compute the frame activity in current frame of video sequence, which take GOP size and frame scene changes in frame into account at the same time. Then, the GOP size control method is obtained based on the computation of the best Distortion-Quantization parameter and the frame activity. Experimental results show that the proposed method not only achieves notable video quality improvements, but also reduced the average distortion, comparisons with the conventional scheme.

Due to the error concealment recommended by H.264 cannot reconstruct the loss image effectively, an efficient error concealment method is proposed in this paper. The proposed scheme adoptively selects a proper concealment candidate to conceal the artifact of a lost block. To determine the best concealment candidate, a trial process in which the concealment candidates are examined based on analyzing motion activity of the MBs. Simulations show that the proposed scheme outperforms the existing method both on PSNR and visual quality obviously.

To solve the dilemma introduced by rate-distortion optimization (RDO) in H.264 rate control, the linear model of MAD prediction is applied. However, this model suits image characteristics locally but in some cases it could be inefficient. If there is a low spatial correlation (i.e., the encoder is processing pictures with varying characteristics), the MAD estimated by the model does not stand for the complexity resulting in the improper quantization parameter (QP) value and image quality degradation. In this paper, the mean square of AC coefficients is introduced into R-D model instead of MAD. Experiments show that the proposed rate control scheme performs well when compared with JlT-G012.