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When faults such as blocking and commutation failure occur in a high-voltage direct current （HVDC） transmission system， they can cause transient voltage fluctuations near the sending-side converter station and lead to the disconnection with power grid. Firstly， the operating principles， response characteristics， and key parameter influences of the grid-forming energy storage open-loop control strategy are analyzed. Then， the reactive response characteristics of the synchronous condenser are analyzed， and a comparison is made between the grid-forming energy storage reactive power control model and the excitation regulation control model. Finally， a semi-physical simulation system is established， including EHVDC， photovoltaics， synchronous condenser， and grid-forming energy storage， to conduct comparative experiments on the effect of suppressing AC transient overvoltage under DC commutation failure. The results indicate that grid-forming energy storage and distributed synchronous condenser with the same capacity can achieve similar effects in terms of reactive transient response speed and the ability to suppress AC transient overvoltage.

Cynarin, a caffeoylquinic acid compound that was mainly extracted from Cynara scolymus L., displays various activities such as antioxidant, antibacterial, choleretic, and hepatoprotective functions. However, the target of cynarin and the mechanism of its hepatoprotective effect are still unclear. To find cynarin’s target, we performed molecular docking analysis, fluorescence-based ligand-binding assay, and reporter gene system assay. Our results indicated that cynarin was a partial agonist of peroxisome proliferator-activated receptor gamma (PPARγ). Further studies showed that cynarin significantly inhibited platelet-derived growth factor (PDGF)-BB-induced proliferation and activation of rat CFSC-8G hepatic stellate cells (HSCs). Our results also revealed that cynarin inhibited PDGF-BB-induced extracellular regulated protein kinase (ERK) and v-akt murine thymoma viral oncogene homolog (AKT) phosphorylation in HSCs. In addition, this inhibition effect was PPARγ dependent since the knockdown of PPARγ significantly attenuated the effects of cynarin on PDGF-BB-induced p-ERK, p-AKT, and α-smooth muscle actin (α-SMA) expressions. Therefore, this study suggests that cynarin is a promising antifibrotic lead compound that inhibits the activation of HSCs, and it works by targeting PPARγ.

In order to meet the growing demand of lymphotherapists, training and patients, guidance, a specific model was designed for training manual lymphatic drainage therapy. The design and application effect of this model is described and discussed in this study. The model can easily let the operator know whether the manipulation is accurate, whether the operation pressure is stable and whether the drainage effect is satisfactory for further adjustments. The design is very close to the clinical practice and the operation of the model is simple and convenient. Preliminary application of this training model showed good effect in better understanding and mastering manipulation technique both in therapists and the patients, as well as their family members. (本研究针对当前淋巴治疗师培训及患者指导上的缺陷, 设计了一种淋巴水肿手法淋巴引流培训教具装置, 并对设计思路及使用效果加以分析。通过使用手法淋巴引流培训教具装置进行操作练习, 可以直观的感受到操作手法的准确性、操作压力的稳定性及引流操作的效果, 增强治疗师的培训成效, 提高患者或者家属掌握的可控性, 进而提升淋巴水肿治疗师培训及患者指导的应用效果。该手法淋巴引流培训教具装置操作简单方便, 应用效果显著。)

The Cu–20 wt% Ag alloy wire rod was prepared using three-chamber vacuum cold mold vertical continuous up-casting followed by multi-pass continuous drawing. The evolution of microstructure, mechanical property, and electrical property of the Cu–20 wt% Ag alloy wire during multi-pass continuous drawing was studied. After multi-pass continuous drawing, the continuous network eutectic structure in the longitudinal section of the as-casted rod was gradually drawn into long fibers that approximately parallel to the axial direction, while the space of the continuous network eutectic structure in the transverse section is getting smaller and smaller. Both the preferred orientation of copper and silver grains are (1,1,1). With the increase of drawing strain (η), the tensile strength of Cu–20 wt% Ag alloy wire gradually increases while the elongation gradually decreases. When the diameter is drawn to 0.02 mm (η = 11.94), the tensile strength of the alloy is 1,682 MPa and elongation is 2.0%. The relationship between tensile strength, elongation, and diameter conforms to Allometric and Boltzmann functions, respectively.

In this study, a methodology was presented to predict density stratified flows in the near-field of submerged bodies. The energy equation in temperature form was solved coupled with momentum and mass conservation equations. Linear stratification was achieved by the definition of the density as a function of temperature. At first, verifications were performed for the stratified flows passing a submerged horizontal circular cylinder, showing excellent agreement with available experimental data. The ability of the method to cope with variable density was demonstrated. Different turbulence models were used for different Re numbers and flow states. Based on the numerical methods proposed in this paper, the stratified flow was studied for the real scale benchmark DAPRA Suboff submarine. The approach used the VOF method for tracing the free surface. Turbulence was implemented with a k − ω based Detached Eddy Simulation (DES) approach. The effects of submarine speed, depth and density gradient on the free surface wave pattern were quantitatively analyzed. It was shown that, with the increasing of the speed of the submarine, the wavelength and wave height of the free surface wave were gradually increasing. The wave height of the free surface wave was gradually reduced as the submarine’s depth increased. Relative to the speed and submarine depth, the changes of the gradient density gradient have negligible effects on the free surface wave field.

The recycling of polyethylene terephthalate (PET) is the most attractive method for PET waste management because it not only decreases the load on landfill space, but also provides opportunities for reducing the use of raw petrochemical products. Therefore, in this investigation, neopentyl glycol is used for alcoholysis of waste PET, and glycolyzed PET product was applied for preparation of the waterborne alkyd resin. Furthermore, the waterborne alkyd-amino baking coatings were prepared from the waterborne alkyd based on glycolyzed waste PET and melamine formaldehyde resin and applied on tinplate. The waterborne alkyd-amino resin films showed excellent adhesion, balanced hardness and flexibility, high gloss and outstanding chemical resistance except for alkali resistance owing to hydrolysis of ester bonds.

This paper mainly studies the longitudinal motion prediction method and control technology of high-speed catamaran using the active hydrofoils. To establish the longitudinal motion equations of the ship basing on the 2.5D theory. Using the CFD software to obtain the hydrodynamic data of the hydrofoil. Bring the hydrodynamic expression of hydrofoils into the longitudinal motion equations of the ship. Predicting the longitudinal motion of High-speed catamaran before and after added the hydrofoils. A specific catamaran has been predicted with this approach, the result indicates this approach is workable and this prediction approach provides the theoretical basis for assessing the stabilization ability of appendages and possess the engineering practical value.

Abstract Background Gastric cancer presents a major health burden worldwide. Therefore, many molecular targeting agents have been evaluated for treatment of gastric cancer. Gefitinib has shown anticancer activity against gastric cancer which work through inhibiting epidermal growth factor receptor (EGFR). However, the effect of gefitinib is limited due to its resistance. Therefore, understanding the mechanisms of gefitinib resistance is desperately needed to formulate novel strategies against gastric cancer. Here, we analyzed resistance mechanism from the crosstalk between EGFR and integrin β4. Methods Integrin β4-expression vector or siRNA were used to analyze the functional effects of integrin β4 on chemoresistance of gastric cancer cells to gefitinib. EGFR and integrin β4 expression, proliferation and apoptosis of gastric cancer cells were assayed by indirect immunofluorescence, western blot, MTT and flow cytometry respectively. EGFR and integrin β4 expression were also assayed on patient samples. Results It was found that the integrin β4 expression was increased in gefitinib-resistant gastric cell line. The upregulated integrin β4 expression was identified to promote gefitinib resistance and proliferation, and inhibit apoptosis, while downregulation of integrin β4 was to inhibit gefitinib resistance and proliferation, and induce apoptosis. Moreover, the overexpression of integrin β4 in SGC7901 cells resulted in the down-regulation of p-EGFR protein levels while down-regulation of integrin β4, significantly resulted in overexpression of p-EGFR. The results of western blot from patients also showed there was obvious negative correlation between p-EGFR and integrin β4 in gastric cancer patients. Conclusion Considering the above results, it is concluded that the interaction of EGFR and integrin β4 may change the sensitivity of gefitinib treatment.

C88H64Cl4N8O12S4Cd2, monoclinic, P21/c (no. 14), a = 13.5247(6) Å, b = 15.3257(7) Å, c = 20.6985(8) Å, β = 101.8630(10)°, V = 4198.7(3) Å3, Z = 2, Rgt(F) = 0.0484, wRref(F2) = 0.0967, T = 173(2) K.

The structure-borne noise while the vehicle passing across the bridge expansion joint is the main source of urban bridge noise. In order to control this noise pollution, 20 bridges including three types of typical expansion joints in Ningbo City were selected, and the noises were measured while vehicle passed across the bridge expansion joints. The measured results are expressed by the Z-weighted sound pressure level, which kept the effect of the low-frequency noise. Then the influence factors of this noise are discussed. The results show that: (1) The sound pressure while vehicle on the bridge expansion joints is much greater than that on the normal road or mid-span of the bridges, which results in significant environmental noise pollution; (2) The wider the gap of the bridge expansion joints, the greater the noise level; (3) The noises produced by the modular expansion joints and comb-plate expansion joints are greater than that from the single-gap expansion joints.

In multipath environment, the conventional Capon beamformer suffers from signal cancellation mainly because of the variation in phase differences (near ±π ) between the array output corresponding to the signal of interest and multipath interferences. To solve this problem, a novel beamforming method for multipath signal reception is proposed. This method uses an antidiagonal unit matrix to construct a new covariance matrix and a constrained steering vector. Then, the weighting vector is obtained based on the minimum variance distortionless response criterion and the array output is performed. The proposed method does not have to estimate the direction of arrival of multipath interferences and uncorrelated interferences; moreover, the array output can improve by adjusting the number of array elements. The simulations demonstrate the superior performance of the proposed method over the conventional Capon and multipath signal reception methods.

The black phase of formamidinium lead iodide (FAPbI3) perovskite shows huge promise as an efficient photovoltaic, but it is not favoured energetically at room temperature, meaning that the undesirable yellow phases are always present alongside it during crystallization1-4. This problem has made it difficult to formulate the fast crystallization process of perovskite and develop guidelines governing the formation of black-phase FAPbI3 (refs. 5,6). Here we use in situ monitoring of the perovskite crystallization process to report an oriented nucleation mechanism that can help to avoid the presence of undesirable phases and improve the performance of photovoltaic devices in different film-processing scenarios. The resulting device has a demonstrated power-conversion efficiency of 25.4% (certified 25.0%) and the module, which has an area of 27.83 cm2, has achieved an impressive certified aperture efficiency of 21.4%.

In this paper, the robot (humanoid robot) soccer activity is decomposed according to the process of Human-Robot football professional skill competition. This paper analyzes the shooting problem of robot in the forward range and outside the range of the door frame, applies it to the rotation angle of robot foot, and gives the mathematical model of linear motion through the force of the center of the ball. Then, the further research direction are discussed.

This paper mainly studies operational model of the famous Computer Games - PlayerUnkown’s BattleGrounds (PUBG), be aimed at human beings in the game or human beings regarded as intelligent robots, including the influence of objective factors and subjective factors on the game results, linear programming model is established for the various factors and the game results, using Excel software, realized in different situations the relationship between various factors and the result of game problem solving and plotting table. To solve the problem 1, the paper find out the trend of the safety area and the random coverage circle of the safety area through statistical data and analyze the data, and then push it to the parachute jumping time and the parachute jumping place. To solve the problem 2, the paper build a game model based on the analysis of the distance between two sides, the judgement of the azimuth and the random running and attacking each other caused by the psychological state of the bullet avoidance, and then, according to experience, how to perform micro manipulation to improve the hit rate. To solve the problem 3, the paper make KDA as a measure of bureau of the game in the best performing team and the best individual (MVP) of the key indicators, through the calculation of KDA for the game and the individual scores and rankings, distribution to determine the winners of the prize gaming contest.