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Monoclonal antibody drugs that inhibit programmed death 1 (PD-1) or programmed death ligand 1 (PD-L1) have been widely used in esophageal cancer (EC) and yielded significant therapeutic responses. However, only a few patients obtain lasting clinical benefits due to primary or acquired drug resistance, and new treatment schemes are urgently needed. The tumor immune microenvironment is the main factor that affects patients' response to immunosuppressive agents. This article will discuss the role of immunosuppressive cells and non-cellular components in the immune process to provide ideas for the next research direction of EC.

The analysis of transient voltage and current characteristics of DPFC （distributed power flow controller） under lightning strikes is an essential consideration in its design and operational management. Firstly， the structure and operational principles of DPFC are introduced， and simulation models are respectively constructed for two scenarios： a centralized arrangement of DPFC sub-modules in substations and a decentralized arrangement along transmission lines. Subsequently， the electromagnetic transient characteristics of DPFC are simulated and analyzed in the case of back strikes on the conductors and circling strikes on the transmission line， and the overvoltage and overcurrent levels at critical positions of DPFC during lightning strikes are thereby obtained. Finally， the differences in overvoltage and overcurrent between the centralized and decentralized arrangement of DPFC sub-modules are compared and analyzed in the case of back strikes and circling strikes. It is concluded that when lightning strikes the lightning conductor， the overvoltage to earth and the overvoltage at the submodule port of the centrally arranged DPFC are larger than the results of the decentralized arrangement； the overcurrents of the submodule of the centrally arranged DPFC and the arrester are smaller than the results of the decentralized arrangement.

To study the energy evolution of rocks under uniaxial compression, uniaxial compression and uniaxial step loading and unloading tests were performed on granite, sandstone, and coal, and the stress-strain curves under different conditions were obtained. The total energy density, elastic energy density and dissipation energy density for the whole process of rock specimens under different conditions were obtained by using the integral and formula. The energy evolution characteristics of rock specimens before and after the peak were analyzed, and the relationship between elastic energy density and total energy density under uniaxial compression were investigated. The results show that the outer envelope of the uniaxial step loading and unloading stress-strain curves have the same trend as the uniaxial compression curves, and the overall deviation exists to a certain extent, and the greater the density of the rock, the smaller the deviation is. The elastic energy density and total energy density of the rock specimens satisfy the linear energy storage law under uniaxial compression and uniaxial step loading and unloading. The energy storage limit of uniaxial compression and uniaxial step loading and unloading, which are almost equal, is obtained by using the linear energy storage law, and the greater the strength of the rock is, the greater the energy storage limit is.

Distributed power flow controller （DPFC） can improve power flow distribution in the power grid and solve the problem of power flow section excess. Based on the topology structure and operation principle of DPFC and with the backing of the world’s first 220 kV DPFC demonstration project， a distributed power flow control simulation model is established. The cases of distributed power flow controllers centrally installed in substations and dispersedly installed in transmission lines are considered， respectively. The overvoltage and overcurrent levels of DPFC key nodes in the case of short-circuit faults on the transmission lines are simulated. Moreover， it is analyzed how fault location influences the DPFC's overvoltage and overcurrent. The calculation results in this paper can provide a reference for DPFC insulation coordination in engineering practice.

In order to realize real-time, accurate and advanced prediction of coal and gas outburst in heading face, a coal and gas outburst earlywarning method based on change of gas concentration was proposed. Through inversion technique of coal gas pressure in heading face, critical condition of coal and gas outburst was determined, and early-warning model of coal and gas outburst was built. A non-contact early-warning system of coal and gas outburst was developed based on change of gas concentration. The application result shows that the system can monitor change of gas concentration and volume information real-timely, and make non-contact and real-time hazard early-warning in coal and gas outburst regional in advance of a work shift.

Based on the electrocaloric effect, a novelty refrigeration device with a ribbon electrocaloric module made of electrocaloric material P(VDF-TrFE-CFE) ternary polymer was proposed. In the device, the ribbon electrocaloric module was driven by a driving wheel and moved sequentially pass through electrodes, hot end, and cold end. In this way, the EC module would undergo four stages of electrocaloric effect. Continuous cooling could be a-chieved at the cold end. A numerical simulation study of a cooling unit of the structure was carried out, and the effects of the polarization time, length, movement speed, temperature span and applied electric field strength of the electrocaloric module on the cooling performance were investigated. The results showed that the polarization time of the electrocaloric module was essential to obtain a stable cooling power density(CPD). The CPD increased with the increase of the length of the electrocaloric module and its motion speed, decreased with the increase of the temperature span at both ends. It also showed a strong positive correlation with the electric field strength. The optimal COP/COPc values existed for different electric field strengths. The cooling power density of a cooling unit reached 6.61 W/cm at a temperature span of 3 K and an electric field strength of 160 MV/m. [ABSTRACT FROM AUTHOR]

Based on the reaction mechanism and research status of iron-based catalysts in direct coal liquefaction process, investigate the influence of pyrite iron-based catalyst on direct coal liquefaction process from the aspects of catalyst size and types, reaction temperature and the like. The analysis of raw coal yield and thermal electric energy production between 2007 and 2012 indicates the domestic coal enterprises status. The influencing factors of direct coal liquefaction decide that it' s the best time to spread this technology in China. Point out the unsolved problems from the view of application. [ABSTRACT FROM AUTHOR]

Background: Da Vinci Surgical System is one of the greatest inventions of the 20th century, which represents the development direction of the precise minimally invasive surgical techniques, the aim of this study was to comparing the short-term outcomes between da Vinci robot-assisted lobectomy and video-assisted thoracic surgery (VATS) lobectomy for non-small cell lung cancer., Methods: 45 pairs of non-small cell lung cancer patients underwent pulmonary lobectomy with da Vinci Robotic assisted thoracoscopic (RATS) and VATS approach during the same period from January 2014 to January 2017. The operative time, estimated blood loss (EBL), total number and total groups of dissected lymph nodes, postoperative duration of drainage, the first day volume of drainage, total volume of drainage were compared., Results: No perioperative death and convertion to thoracotomy occured in both groups. There were significant difference between RATS group and VATS group in EBL [(50.30±32.33) mL vs (208.60±132.63) mL], the first day volume of drainage [(275.00±145.42) mL vs (347.60±125.80) mL], the dissected total number [(22.67±9.67) vs (15.51±5.41)] and total team [(6.31±1.43) vs (4.91±1.04)] of lymph node. There were no significant difference in other outcomes., Conclusions: RATS is safe and effective and took better short-outcomes than VATS in non-small cell lung cancer.

A sensitive and convenient liquid chromatography-tandem mass spectrometric method was developed for the determination of 16 pesticides such as imidacloprid, prochloraz, difenoconazole, azoxystrobin, and thiamethoxam in fruits and vegetables. After compared with methanol and acetone-cyclohexane (1:2, v/v), acetonitrile was chosen as the extraction solvent. The samples were extracted by acetonitrile in high-speed homogenization. The extraction solution was cleaned up by liquid-liquid extraction, and the supernatant was collected. In this work, QuEChERS exhibited much higher efficiency than Carbon-NH2 solid-phase extraction in purification. The pigments and organic acids were removed by purge line (150 mg primary secondary amine (PSA) sorbent and 900 mg absolute magnesium sulfate), leading to the decrease of the background interferences. The average recoveries of the 16 pesticides were almost in the range of 75%-111% at the three spiked levels, and the relative standard deviations were less than 16%. The qualitative analysis and quantitative analysis were investigated by LC-MS/MS and matrix-matched calibration curves. The results showed that the method of QuEChERS combined with LC-MS/MS is rapid, accurate and sensitive for the determination of the 16 pesticide residues in fruits and vegetables.