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Objective: Due to the tumor immune microenvironment (TIME) complexity and cancer heterogeneity, the clinical outcomes of hepatocellular carcinoma (HCC) are barely elicited from the conventional treatment options, even from the promising anti-cancer immunotherapy. As a suppressive TIME-related marker, the role played by cyclooxygenase-2 (COX-2) in HCC TIME, and its potential effects on anti-cancer T cell immune response remains unknown. In our study, to investigate the COX-2-dependent immune regulation pathway, we verified that the macrophages phenotypes were correlated to COX-2/PGE2 expressions among HCC patients. A multi-cellular co-culture platform containing HCC cells, macrophages, and T cells were established to mimic HCC TIME in vitro and in animal model. M2 macrophage polarization and activated CD8(+) T cells exhaustion were observed under high COX-2 levels in HCC cells, with further evaluation using CRISPR/Cas9-based PTGS2 knocking out and COX-2 blockade (celecoxib) treatment controls. PGE2, TGF-β, Granzyme B, and IFN-γ levels were testified by flow cytometry and ELISA to fully understand the mechanism of COX-2 suppressive effects on T cell-based anti-HCC responses. The activation of the TGF-β pathway evaluated by auto-western blot in T cells was confirmed which increased the level of phosphorylated Smad3, phosphorylated Samd2, and FoxP1, leading to T cell de-lymphotoxin. In conclusion, high COX-2-expressing HCC cell lines can induce anti-tumor abilities exhaustion in activated CD8(+) T cell through M2 TAMs polarization and TGF beta pathway. COX-2 inhibitors may reduce the inhibitory effect on CD8(+) T cells through regulating TAMs in TIME, thus enhance the T cell-based cytotoxicity and improve the prognosis of HCC patients.

The growing tendency of the abnormity and accident which caused by arc fault has already become the social harmfulness in the power system. With the extensive use of electrical equipment, arc fault has the features of randomness, which further increase the difficulty to recognize arc and set higher requirement on the performance of arc fault protection switch. In this paper, a comprehensive test system is developed to generate arc and study the characteristics of arc fault on the basis of integrated design and multi-threading technique. Then the effectiveness and credibility of arc fault simulation devices have been verified and the characteristics of arc fault are analyzed under different loads. Experiments show that characteristic of arc fault are influenced by the fault reasons and load in series. The system can meet the requirements of arc fault protection switch research, and can provide experimental condition and data support for the research of arc fault detection technique.

MSs (Magnetic switches) have been widely used in situations where frequent on-off load are required. The operating voltage range of the conventional magnetic switch is usually between 85% and 110% of the rated control voltage. When the control voltage sags, the narrow operating voltage range might lead the conventional MS to malfunction causing an unintended operation of load. To address this problem, a control module is designed in this paper: the control parameters of the module are obtained from simulation result of MS by Maxwell, a bi-coefficient feedback control strategy is established to improve the accuracy of coil current control, and a waveform detection strategy is used to shorten the time from the opening operation occurred to the MS switching off the load for increasing the operation frequency.