Abstract: Provided are transaminase mutants and uses thereof. The transaminase mutant is obtained by one or more amino acid mutations occurring in SEQ ID NO: 2 or is a mutant with a conserved amino acid mutation obtained by taking the sequence SEQ ID NO: 1 of a wild-type CvTA transaminase as a reference. Compared with wild-type transaminases, the catalytic activity of the mutant is improved to different degrees, so that the production efficiency of chiral amine compound synthesis may be improved.

Abstract: Provided is a method for synthesizing a chiral amine compound. A transaminase is used to transaminate a ketone substrate under the action of an amino donor, to obtain the chiral amine compound; and the conserved amino acid sequence region of the transaminase at least includes a region 1 (MAGLWCVN) and a region 2 (YNTFFKT). With the transaminase with the specific conserved amino acid sequence region to synthesize a large sterically hindered chiral amine, the enzyme catalytic reaction volume is small, the synthesizing route is short, the product yield is high, a high-cost noble metal is not required for catalysis under the synthesizing conditions, three wastes are reduced, and the production cost is saved.

Abstract: Provided are a bovine rotavirus fusion protein and calf diarrhea multivalent vaccine. The bovine rotavirus fusion protein contains a VP6 fragment, wherein the VP6 fragment contains an amino acid sequence as represented by SEQ ID NO. 4, and at least one loop region of the following (a)˜(c) is substituted with an antigenic epitope derived from bovine coronavirus and/or an antigenic epitope derived from E. coli: (a) amino acid residues of sites 168-177; with an amino acid sequence as represented by SEQ ID NO. 1; (b) amino acid residues of sites 194-205; with an amino acid sequence as represented by SEQ ID NO. 2; and (a) amino acid residues of sites 296-316, with an amino acid sequence as represented by SEQ ID NO. 3, The bovine rotavirus fusion protein contains a plurality of antigenic epitopes, and can enable a host to generate a plurality of antibodies after immunizing the host.

Abstract: Provided are an esterase mutant and use thereof. The amino acid sequence of the esterase mutant has a sequence as shown in SEQ ID NO: 1, and sites at which amino acid mutations occur include an N51G site.

Abstract: Provided are an amino acid dehydrogenase mutant and use thereof. The amino acid sequence of the amino acid dehydrogenase mutant has a sequence as shown in SEQ ID NO: 1, and sites at which amino acid mutations occur include a K144G site.

Abstract: A ball picking robot and a ball unloading method using the same. The ball picking robot includes a chassis, an L-shaped hanging lug, a ball storage frame, an electric push rod disposed on the chassis, a baffle disposed on the chassis, a bracket disposed on the chassis and a drive motor for driving the electric push rod to move. A movable end of the electric push rod is connected with one end of the L-shaped hanging lug, the other end of the L-shaped hanging lug is connected with a side of the ball storage frame, and a camera is disposed on the bracket.

Abstract: Disclosed is a device for measuring speed of a tennis ball, which includes: a housing, a power supply, a main control device, a sensor device, a transmission device, a clamping device and a limiting device. The clamping device is clamped at the serve opening of a tennis ball machine, which can detect the serve speed of a tennis ball accurately with simple operation. The transmission device is engaged with the second sensor device, and the housing is slidably connected with the second sensor device. The emitting ends of the second sensor device and the first sensor device are positioned in the same vertical plane. The limiting device is connected with the second sensor device to limit excessive operation of the transmission device.

Abstract: A ball picking robot and a ball unloading method using the same. The ball picking robot includes a chassis, an L-shaped hanging lug, a ball storage frame, an electric push rod disposed on the chassis, a baffle disposed on the chassis, a bracket disposed on the chassis and a drive motor for driving the electric push rod to move. A movable end of the electric push rod is connected with one end of the L-shaped hanging lug, the other end of the L-shaped hanging lug is connected with a side of the ball storage frame, and a camera is disposed on the bracket.

Abstract: Disclosed is a device for measuring speed of a tennis ball, which includes: a housing, a power supply, a main control device, a sensor device, a transmission device, a clamping device and a limiting device. The clamping device is clamped at the serve opening of a tennis ball machine, which can detect the serve speed of a tennis ball accurately with simple operation. The transmission device is engaged with the second sensor device, and the housing is slidably connected with the second sensor device. The emitting ends of the second sensor device and the first sensor device are positioned in the same vertical plane. The limiting device is connected with the second sensor device to limit excessive operation of the transmission device.