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Pterostilbene is a natural resveratrol dimethylated analogue that has anticancer effects against a variety of cancers. It has better and oral absorption than resveratrol. In this paper, the molecular mechanism of p53-53BP1 complex regulating pterostilbene on the proliferation of lung cancer cells was elaborated from the aspects of the regulatory mechanism of pterostilbene on lung cancer cells.

The phytoalexin resveratrol exhibits anti-tumour activity in many types of cancer. In this study, we showed that resveratrol suppressed the survival of gastric tumour cells both in vivo and in vitro. Resveratrol promoted apoptosis, autophagy and endoplasmic reticulum (ER) stress in a dosedependent manner. In conclusion, resveratrol inhibited cancer cell survival, while knockdown of lncRNA H19 resulted in increased sensitivity to resveratrol therapy.

In HVDC system, the coordinated control of reactive power compensation equipment in converter station is of great significance to improve the stability of DC system, especially the DC system with frequent fluctuation of DC transmission power. This paper presents a multi-mode coordinated control strategy for the coordination of the new-generation synchronous condensers and the capacitor bank, which mainly includes the steady-state voltage regulation mode of the converter bus voltage tracking rated voltage without static error, the automatic voltage control (AVC) mode of the converter station participating in the voltage regulation of the near-area AC system, and the short-circuit fault of the converter bus. Transient control mode to suppress voltage fluctuation and commutation failure. Finally, based on the actual engineering parameters, the proposed strategy is validated in the electromagnetic transient simulation software (PSCAD).The simulation results demonstrate the rationality and effectiveness of the proposed strategy.

In order to meet the higher demand of dynamic reactive power support is put forward in the UHV DC power transmission project, the new-generation synchronous condensers are applied in the UHV DC/AC. However, the new-generation synchronous condensers needs to coordinate with DC. This means that the excitation control system of the new-generation synchronous condenser has changed greatly, and its control parameters need to be setting to improve the reactive power fast output ability. In this paper, the rapidity and stability of the system is considered, and the open-loop and closed-loop models of the control system are established. Then, a setting method for excitation control parameters of new-generation synchronous condenser is proposed. This is of great significance to the actual operation control of the new-generation synchronous condensers.

In recent years, with the increasingly growth of power grid scale and its load, the requirements for security and stability of the power grid and reliability of power supply are gradually improved. In this paper, the superposition principle of power flow transfer in component state space considering multiple faults and maintenance mode of power grid is proved based on that the characteristic of the power flow transfer after N-1 contingency is approximate linearity. According to user-defined set of transmission sections and set of faults and maintenance states, a mathematical model based on state superposition algorithm to calculate steady-state security region of transmission section is proposed. The correctness of the model and the validity of the solution are verified by the actual example of Hubei power grid.

To solve the problem of thermal overload failure in dual-mass flywheel (DMF), we performed temperature field calculation and thermal analysis of the secondary flywheel in DMF. Based on the results of this analysis, we performed thermal stress analysis on the secondary flywheel. The heat transform model was built for the secondary flywheel using the thermodynamics theory. Finite element model (FEM) was built for the secondary flywheel using ABAQUS 6.12-3 software. This model was solved to obtain the distributions of the temperature field and thermal stress in the secondary flywheel after it completed five engagement-disengagement cycles. Finally, thermal shock test was conducted for the secondary flywheel on the thermal shock test bench. We performed a targeted test to verify the accuracy of thermal analysis of secondary flywheel. The analysis method can be used to optimize product parameters such as the product thickness.

In order to meet the higher demand of dynamic reactive power support is put forward in the Ultra High Voltage Direct Current(UHV DC) power transmission project, the new-generation synchronous condensers are applied in the UHV DC-AC. However, in order to provide bidirectional transient reactive power characteristics during AC and DC grid fault condition, especially to reduce the commutation failure phenomenon at the inverter station, there are great changes in the main body and excitation control system of the new-generation synchronous condensers compared with the same-capacity generators. In this paper, the limiting model of excitation system for the new-generation synchronous condensers under low excitation and strong excitation conditions are established. Then, the expression of sub-transient reactive power for the new-generation synchronous condenser is derived and the reactive power characteristics considering the influence of excitation regulation are also obtained. In addition, the transient reactive power demand of the high-voltage direct current(HVDC) transmission system is also analyzed. Finally, the simulation model of the new-generation synchronous condensers access to UHV DC power grids are built based on the PSCAD software. The simulation results verify the support effect of the new-generation synchronous condensers on DC transient reactive power.

In order to meet the higher demand of dynamic reactive power support is put forward in the UHV DC power transmission project, the new-generation synchronous condensers are applied in the UHV DC/AC. However, the excitation system of the new-generation synchronous condensers and the reactive power compensation device of the DC converter station are controlled individually, and there is no reasonable coordination strategy. Therefore, the transient reactive power support capability of the synchronous condenser is analyzed in this paper considering with excitation control characteristics. Then, the transient reactive power demand of the HVDC transmission system is also analyzed. Based on this, the coordinated control strategy of the reactive power compensation device in DC converter station with synchronous condensers are proposed, and a coordinated control system is given in this paper. Finally, the simulation model of the new-generation synchronous condensers access to UHV DC power grids are built based on the PSCAD software. The digital simulation results validate the proposed coordinated control strategy.