Abstract: Disclosed are a step-by-step paired and up-down reciprocating combined fishway and a fish passage method thereof, belonging to the technical field of fish passage facilities. The present disclosure aims to provide an efficient fish passage technology for a low-head water control project, which overcomes the defects of long construction length and low fish passage efficiency of the traditional fishway. The present disclosure includes several fishway units, a mechanical transmission system, a fish repelling system, a control system, and a recovery cableway. Under the combined action of the mechanical transmission system and the fish repelling system, the fishway units reciprocate up and down step by step to form a fish passage way. The weight of the fishway units is balanced through the rotation of coaxial eccentric wheels, and the energy consumption of the mechanical transmission system is reduced.

Abstract: A lens and an illumination method thereof relates to the field of illumination technologies. The lens is provided with a concave space for accommodating a light source, a first irradiation part is formed on a first side of an inner wall of the concave space, and second irradiation parts are formed on the bottom and a second side of the inner wall of the concave space; a main light beam emitted by the first irradiation part and a main light beam emitted by the second irradiation parts form an acute angle. By means of the present invention, an upper region and a lower region of a to-be-irradiated object can be illuminated through one light source at the same time, and the light source arrangement cost is reduced.

Abstract: Provided is a gene for trypsin-like serine protease, a protein encoded thereby and use thereof. The nucleotide sequence of the gene for trypsin-like serine protease is set forth in SEQ ID No. 1, the amino acid sequence of the protein encoded by the gene for trypsin-like serine protease is set forth in SEQ ID No. 2. The protein encoded by the gene provided by the present disclosure is capable of inhibiting P. aeruginosa, A. hydrophila, V. parahaemolyticus and V. harveyi.