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Porcine reproductive and respiratory syndrome(PRRS) caused by porcine reproductive and respiratory syndrome virus(PRRSV) is one of the most infectious diseases in the swine industry worldwide, causing big economic losses. Vaccines are major weapons against PRRSV, however, current available vaccines have several limitations. Developing chemical drugs as alternatives is required. On the basis of traditional medical knowledge, we purposely selected 15 natural products originated from Chinese herbs with anti-infectious effects. Their antiviral activities were evaluated by PRRSV-induced cytopathic effect(CPE) on MARC-145 cells and reverse transcription polymerase chain reaction(RT-PCR) assay. Compounds ethoxysanguinarine(EOSG) and atractylodinol were found to be the hits which could significantly reduce PRRSV-associated CPE with 50% inhibited concentration(IC50) values of 7.9 and 39.4 μmol/L, respectively. Meanwhile, compounds ethoxysanguinarine and atractylodinol significantly decreased mRNA expression of ORF7 gene in a dose-dependent manner. Study results suggest that compounds ethoxysanguinarine and atractylodinol may be useful anti-PRRSV drugs for swine industry or the hits for further lead optimization.

In view of the natural gas leakage monitoring status, a distributed monitoring system is designed based on CAN bus, which is composed of Master Controller, CAN bus, and data acquisition modules, etc. As well as the circuit diagram and the flow chart of software are introduced in detail. The results indicate that the distributed natural gas leakage monitoring system can fulfill the task of gas leakage state display and alarm successfully in laboratory test, by using distributed structure, the system can be easily expended, and it has the character of reliability and flexibility.

vThe 4R principle refers to reduce, reuse, recycle and regeneration, which should be implemented in the process of concrete treatment. In terms of the special micro-structural properties and self-repairing capacity, concrete is one kind of regenerative construction materials. Through proper handlings, self-repairing (crack close-up) of concrete cracks is possible in the concrete hydration damaged region. Due to the effect of heterogeneous nucleation and subsequent crystal growth of calcium hydroxide, a better bonding strength forms interlocking the new and old concrete interfaces. A proposal on the relationship between the self-repairing, regeneration function of concrete and the rehabilitation of historic buildings is suggested, this is based on the formed process of the bonding strength of the interfaces and the function on concrete repairing. Besides the constitution and features of the microstructure of concrete, the relationship between the micro-structure and the macro-mechanical property is also investigated in this paper