Abstract: In certain aspects, a three-dimensional (3D) memory device includes a stack structure including alternating conductive layers and dielectric layers and having at least two core regions and a staircase region between the two core regions, and bridge structures connecting the two core regions and extending through the staircase region in a first direction. A first bridge structure of the bridge structures includes at least two current paths between the two core regions.

Abstract: A three-dimensional (3D) memory device is provided. In an example, the 3D memory device includes a staircase and a plurality of groups of support structures through the staircase. The plurality of groups of support structures are arranged in a first direction, and each of the groups of support structures comprises three support structures, wherein projections of the three support structures form a triangular shape in a plane parallel to the first direction.

Abstract: A paramyxovirus vaccine strain for novel coronavirus pneumonia and a construction method thereof are provided. The method includes performing a recombination of N and F genes of Newcastle disease virus type VII of Paramyxoviridae with P, M, H, L genes of Canine distemper virus of Paramyxoviridae to obtain a recombinant virus, inserting S1 gene of the novel coronavirus between the P and M genes of the recombinant virus to obtain a recombinant vector. The vaccine strain constructed can stably and efficiently express the novel coronavirus S1 protein, and induce the body to produce antibodies; and the recombined virus vaccine strain can stimulate the human body to produce mucosal immunity, and the prepared vaccine can be vaccinated through a nasal spray. Moreover, the vaccine strain can be tested in poultry and dogs, saving time, reducing costs, and being more conducive to actual production due to large output.

Abstract: A paramyxovirus vaccine strain for novel coronavirus pneumonia and a construction method thereof are provided. The method includes performing a recombination of N and F genes of Newcastle disease virus type VII of Paramyxoviridae with P, M, H, L genes of Canine distemper virus of Paramyxoviridae to obtain a recombinant virus, inserting S1 gene of the novel coronavirus between the P and M genes of the recombinant virus to obtain a recombinant vector. The vaccine strain constructed can stably and efficiently express the novel coronavirus S1 protein, and induce the body to produce antibodies; and the recombined virus vaccine strain can stimulate the human body to produce mucosal immunity, and the prepared vaccine can be vaccinated through a nasal spray. Moreover, the vaccine strain can be tested in poultry and dogs, saving time, reducing costs, and being more conducive to actual production due to large output.