Abstract: Techniques are described for performing physical uplink shared channel (PUSCH) transmission. An example wireless communication method includes performing, by a communication device, an uplink transmission, where the uplink transmission is performed using a precoder, where the precoder is based on one or more sounding reference signal (SRS) resources, one or more ranks, and/or one or more precoding matrix indicators, and where one precoding matrix indicator of the one or more precoding matrix indicators indicates a precoding matrix for a rank.

Abstract: Provided are a TEV protease variant, a fusion protein thereof, a preparation method therefor and the use thereof. Provided are a TEV protease variant with unique properties obtained by screening and a fusion protein thereof. The TEV protease variant has a low enzyme cleavage activity during expression in hosts, and preferably has a lower enzyme cleavage activity compared to an S219V variant having an amino acid sequence as shown in SEQ ID NO: 10. The enzyme cleavage site of the TEV protease variant is selected from EXXYXQG/S/H, wherein X is any amino acid residue, and the enzyme cleavage site is preferably selected from SEQ ID NO: 7 and 8. Fusion expression using the TEV protease variant of the present invention and a polypeptide can be used for preparing a polypeptide quickly and efficiently, thereby solving the problems currently present in the process of the recombinant production of a polypeptide.

Abstract: The present invention discloses a push-type safety protection mechanism of a blood collection needle.

Abstract: Provided are a TEV protease variant, a fusion protein thereof, a preparation method therefor and the use thereof. Provided are a TEV protease variant with unique properties obtained by screening and a fusion protein thereof. The TEV protease variant has a low enzyme cleavage activity during expression in hosts, and preferably has a lower enzyme cleavage activity compared to an S219V variant having an amino acid sequence as shown in SEQ ID NO: 10. The enzyme cleavage site of the TEV protease variant is selected from EXXYXQG/S/H, wherein X is any amino acid residue, and the enzyme cleavage site is preferably selected from SEQ ID NO: 7 and 8. Fusion expression using the TEV protease variant of the present invention and a polypeptide can be used for preparing a polypeptide quickly and efficiently, thereby solving the problems currently present in the process of the recombinant production of a polypeptide.

Abstract: The present invention relates to a method for screening a protease variant and the obtained protease variant, and the protease variant has a special performance. The method for screening the protease variant comprises the following steps: (1) constructing a protease random mutation library, optimizing a protease random mutation virus library, and optimizing a protease random mutation phage library; (2) for the protease random mutation library, optimizing the protease random mutation virus library, and optimizing the protease random mutation phage library and screening a protease variant having weak protease enzyme-cutting activity in a host or a similar condition and having protease enzyme-cutting activity in an in vitro denaturation condition; and (3) the step of optionally characterizing the protease variant, wherein the protease optimizes TEV protease or enterokinase. The protease variant in the present invention facilitates industrial production of protein.

Abstract: An anti-derailment safety device is in a shape of an inverted letter L and includes a transverse portion and a longitudinal portion perpendicular to the transverse portion at a side below the transverse portion; two sides of the transverse portion in a width direction of the transverse portion are each provided with an installation seat formed by a wing plate extending outwardly, and bolt holes are provided on the installation seat; and an inner side surface of the longitudinal portion is a stopping surface.

Abstract: An anti-derailment safety device is in a shape of an inverted letter L and includes a transverse portion and a longitudinal portion perpendicular to the transverse portion at a side below the transverse portion; two sides of the transverse portion in a width direction of the transverse portion are each provided with an installation seat formed by a wing plate extending outwardly, and bolt holes are provided on the installation seat; and an inner side surface of the longitudinal portion is a stopping surface.

Abstract: A railway vehicle and an axle box structure thereof are provided. The axle box structure includes an axle box body and a positioning joint mounting seat, and a bearing mounting cavity is provided inside the axle box body. The positioning joint mounting seat is provided with a mounting cavity configured to mount a positioning joint, a longitudinal center line of the axle box body is in parallel with a longitudinal center plane of the positioning joint mounting seat, and the longitudinal center plane of the positioning joint mounting seat is outwardly deviated with respect to a longitudinal center plane of the axle box body. In this way, a large space can be left for mounting the brake clamp, and the mounting and replacing of the brake clamp and the wheel set can be facilitated.

Abstract: A railway vehicle and an axle box structure thereof are provided. The axle box structure includes an axle box body and a positioning joint mounting seat, and a bearing mounting cavity is provided inside the axle box body. The positioning joint mounting seat is provided with a mounting cavity configured to mount a positioning joint, a longitudinal center line of the axle box body is in parallel with a longitudinal center plane of the positioning joint mounting seat, and the longitudinal center plane of the positioning joint mounting seat is outwardly deviated with respect to a longitudinal center plane of the axle box body. In this way, a large space can be left for mounting the brake clamp, and the mounting and replacing of the brake clamp and the wheel set can be facilitated.