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Polyhydroxy stilbenes have been reported to possess various biological activities and have potential for treatment of Alzheimer's disease. Tetrahydroxystilbene glucoside is one of the major polyhydroxy stilbenes, which provides the underlying therapeutic activities for neuroprotective actions in various experimental conditions. This study investigates the impact of a tetrahydroxystilbene glucoside remedy for cognitive disorder and oxidative stress in Aβ1-42-induced Alzheimer's disease mice and clarifies the mechanisms of action through the Kelch-like erythroid cell-derived protein with conserved non-coding homology-associated protein 1/nuclear factor erythroid 2-related factor pathway. It was found that the swimming time of Aβ1-42-induced mice treated with tetrahydroxystilbene glucoside (30, 60, and 120 mg/kg) was significantly increased in the target quadrant of a Morris water maze experiment and the number of avoidances was increased during a passive avoidance experiment, Moreover, tetrahydroxystilbene glucoside attenuated Aβ1-42-induced memory impairment. However, the locomotor and exploratory activity of mice were not affected. Tetrahydroxystilbene glucoside clearly decreased the levels of malondialdehyde and oxidized glutathione in both hippocampus and cortex compared with the Aβ1-42-treated group, and also clearly increased the level of glutathione and activities of catalase and superoxide dismutase in those tissues. The results of this study demonstrated that tetrahydroxystilbene glucoside increased nuclear factor erythroid 2-related factor and heme oxygenase-1 protein expression and decreased Kelch-like erythroid cell-derived protein with conserved non-coding homology-associated protein 1 protein expression in a concentration-dependent manner in Aβ1-42-treated mice, which involved the Kelch-like erythroid cell-derived protein with conserved non-coding homology-associated protein 1/nuclear factor erythroid 2-related factor antioxidant pathway in hippocampus and cerebral cortex tissue. These results demonstrate that tetrahydroxystilbene glucoside as a natural drug that may provide a potential treatment for Alzheimer's disease.

A high-speed on/off valve (HSV) is generally the core component of a digital hydraulic transmission system. Therefore, its dynamic characteristics often restrict the overall performance of the digital hydraulic system. Most of the current studies focus on the optimization on the dynamic characteristics or the energy characteristics, few studies have comprehensively considered the two characteristics of the valve together. In this paper, a pre-existing control algorithm (PECA) is proposed to improve the dynamic characteristics of the HSV, and simultaneously optimize the power losses of the HSV to improve its energy conversion efficiency. The results show that, compared with the traditional single-voltage driven strategy, the opening time of the PECA decreases by 29.4%, the closing time decreases by 59.6%, and the energy conversion rate increases by 7.9%.

During the commissioning phase of pressurized water reactor (PWR) nuclear power station,a temporary filter shall be installed in the pump inlet to prevent foreign body in fluid entering the pump body, which could cause disaster effect on the pump during safety and normal operation. The strainer blockage was an urgent problem to be solved, as well as the operation of the filter was monitored by effective means. In order to decrease the risk of human failures and realize intelligent control, a protection device was designed in this paper. This device could monitor the variation of pressure differential between front and back sides of pump’s inlet filter accompany with functions of alarming and pump emergency shutdown. The corresponding alarm would be generated when the pressure differential reaches the set values, and the command to pump shut down could be generated when reaching the jump threshold, to ensure the safety of nuclear classified important equipment.

Cloud computing is the extension of parallel computing technology that provide robust storage and computing capacity for geospatial information services. The author introduces the classifications, architecture and characteristic of cloud computing, analyzes the relationship among the SaaS model, traditional service model and SOA, proposes a new geospatial information system architecture that fits to the ‘software-and-service’ model of cloud computing, at last studies the key technologies for the architecture.