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The electric servo loading system can more fully test the stability and dynamic performance of the motor body and controller, and is widely used in the research and development of flight control systems. The traditional dual PWM converter has hysteresis characteristics. When the load power is abrupt, especially when the load power is suddenly reduced, the DC output voltage of the PWM rectifier will fluctuate. Voltage fluctuations can be suppressed by increasing the capacitance of the DC side capacitors, but an increase in the capacitance capacity causes the adjustment time of the system to become longer and slows down the response speed of the system. By analyzing the fluctuation of DC output voltage caused by sudden load change, a variable feedforward control method for iq load power is proposed, which uses the method of compensating the active current on the grid side to achieve instantaneous active power balance on both sides. The simulation results show that the method reduces the DC capacitor capacity and improves the dynamic response speed of the system.

A number of novel 2-(N-(2-(5,5-dimethyl-1,3-dioxane-2-yl)ethyl)aminoacyl)amino-2-deoxy- d-glucopyranoside were synthesized from a readily available starting material, glucosamine, 2,2-dimethyl-1,3-propanediol and 1,1,3,3-tetramethoxypropane, and evaluated for their anti-inflammatory activity. Our results showed that all of the compounds tested exhibited a significant inhibition of xylene-induced inflammation in mice.

The aim of the present study was to characterize the effects of early growth response factor-1 DNA enzyme (EDRz) in a rat abdominal aortic aneurysm (AAA) model to determine the mechanism by which EDRz inhibits AAA and affects the formation of AAA by regulating the activity of matrix metalloproteinase (MMP)-2 and MMP-9. EDRz was transfected into the abdominal aorta of rats using the jetPRIME transfection reagent following infusion with elastase. Fluorescent microscopy, hematoxylin and eosin staining, ultrastructural analysis, reverse transcription-quantitative polymerase chain reaction, western blotting and immunohistochemical analysis were performed to characterize the response to EDRz. The EDRz group showed minimal aneurysm formation when compared with the control group, with significantly lower aortic diameter expansion (2.5±0.1 vs. 3.5±0.1 mm; P

In this study, several novel coumarin derivatives, 7-hydroxy-2-oxo-2H-chromene-3-carboxyl-Trp-Trp-AA-OBzl compounds, were designed and synthesized as potential anticancer agents. Their in vitro cytotoxic activities were evaluated using methylthiazoltetrazolium (MTT) assay. The anti-tumor activity of the newly coumarin derivatives was determined in a S180 bearing mouse model and some of the compounds demonstrated tumor growth inhibition similar to the positive control, doxorubicin. Compared to doxorubicin, most of the compounds exhibited enhanced immunologic function suggesting a relatively minor toxic effect. The intercalation of the coumarin derivatives synthesized with calf thymus (CT) DNA was also studied.

In this study, several novel peptidomimetics were designed and synthesized as potential anti-inflammatory agents. Their anti-inflammatory activity was evaluated using a xylene-induced ear edema model assay. Some of the compounds demonstrated inhibitory activity against xylene-induced inflammation similar to the positive control, aspirin.