Search

In order to improve the disadvantages of the existing variable step size LMS (least mean square) algorithm in terms of performance, this paper proposed an improved variable step size adaptive harmonic detection algorithm. The algorithm was based on the original hyperbolic tangent function and introduced factor T(n) that contained the input signal, tracked the changes of input signal, in order to analyze the performance of the algorithm to improve its anti-jamming capability. And it added compensation term to ensure the algorithm convergence speed. At the same time it replaced the fixed step size range restriction of step iterative formula by dynamic change restriction, which made the step change tend to be smoother and steady-state misadjustment was relatively small. Finally, it used normalization method to update weight formula to improve the dynamic range of the input signal. The results of simulation show that the new algorithm compares to the existing variable step harmonic detection algorithm improves greatly in terms of convergence speed, tracking capability, anti-interference ability, stable error. It is a feasible, effective, and has certain engineering application value algorithm. [ABSTRACT FROM AUTHOR]

Objective To study the expression and significance of myeloid-derived suppressor cell (MDSC)-associated chemokines in the spleen of hepatoma H22-bearing mice. Methods The percentage of splenic MDSCs was examined by flow cytometry. Splenic MDSCs were sorted using flow cytometry and co-cultured with activated splenocytes, and then the level of IFN-γ in the supernatant of co-cultured cells was assayed by ELISA. The murine orthotopic hepatoma model was established. The differential cytokine expression in the spleens of normal and tumor-bearing mice was assayed by protein chip, and splenic MDSC-associated chemokines were verified using ELISA. The chemokine receptors on splenic MDSCs were also detected by flow cytometry. Results The percentage of splenic MDSCs was markedly raised in the tumor-bearing mice, and splenic MDSCs exhibited immune-inhibitory function. Ten up-regulated cytokines and nine down-regulated ones were found out using protein chip. Among the up-regulated cytokines, 5 cytokines were chemokines, namely B lymphocyte chemoattractant (BLC), chemokine (C-X-C motif) ligand 16 (CXCL16), macrophage/monocyte chemotactic protein-5 (MCP-5), macrophage inflammatory protein 1γ (MIP-1γ) and MIP-2. The level of splenic MDSC-associated chemokine MIP-1γ significantly increased in the spleen of tumor-bearing mice, and its receptor CCR1 was also expressed on the cell surface of splenic MDSCs. Conclusion Splenic MDSC-associated chemokine MIP-1γ and its receptor CCR1 were obtained by protein chip, and they might be associated with the accumulation of splenic MDSCs in hepatoma H22-bearing mice.

The management of healthcare services for the suspected cases in non-designated hospitalsis a serious concern in controlling coronavirus disease 2019 (COVID-19) epidemic. Owing to the complexity of care providers, large requirement of medical supplies as well as the possible needs off frequent transfers, the major difficulty is preventing the coronavirus from spreading while caring the suspected critical cases before the 2019 novel coronavirus ribonucleic acid test results are reported. For the purpose of enhancing the prevention of the propagation of COVID-19, this article puts emphasis on the following aspects in non-designated hospital Peking University Third Hospital: preparatory procedures of receiving critical suspected patients, the management of medical personnel during the waiting session of RNA test results, the delivering procedures of testing samples, the management of referred medical wastes, daily operations including the cleaning and sanitizing of caring units and the management of related patients after the testing session.