Abstract: The disclosure provides an ultrasonic signal detection circuit including a sensing circuit, a unidirectional conduction circuit and a source follower circuit. The sensing circuit is connected to an input terminal of the source follower circuit through the unidirectional conduction circuit; the sensing circuit is configured to generate a piezoelectric signal according to a received ultrasonic echo signal and output the piezoelectric signal to the unidirectional conduction circuit. The piezoelectric signal is an alternating current signal; the unidirectional conduction circuit is configured to rectify the alternating current signal to only allow a forward or a reverse current portion thereof to pass through. The forward/reverse current portion charges/discharges the input terminal of the source follower circuit after passing through the unidirectional conduction circuit.

Abstract: An optical sensor array substrate and an optical fingerprint reader are provided. The optical sensor array substrate includes a substrate including a detection area which includes a plurality of photosensitive pixels. Photosensitive pixel includes: a TFT arranged on the substrate; a storage capacitor arranged on the substrate and having a first capacitor plate, and a second capacitor plate electrically connected to the source or drain of the TFT; a photosensitive element, having one end electrically connected to the second capacitor plate; a first electrode layer electrically connected to another end of the photosensitive element. On the substrate, an orthographic projection of the second capacitor plate at least partially overlaps with that of the first electrode layer, and the first capacitor plate is located in the same layer and has the same material as the gate of the TFT.

Abstract: The invention relates to a 2-isopropyl malate synthase, a genetically engineered bacterium for producing L-leucine and application thereof and belongs to the field of metabolic engineering. The genetically engineered bacterium is obtained by overexpressing an isopropyl malate synthase coding gene leuAM for relieving feedback inhibition by L-leucine, an acetohydroxy acid synthase coding gene ilvBNM for relieving feedback inhibition by L-isoleucine, a 3-isopropyl malate dehydrogenase coding gene leuB and a 3-isopropyl malate dehydratase coding gene leuCD in host cells. The genetically engineered bacterium for producing the L-leucine is free from nutritional deficiency, rapid in growth, short in fermentation period, high in yield and high in conversion rate.

Abstract: A recombinant bacterium with a high PHA yield and its construction method provide an engineered microorganism that can be used for the production of polyhydroxyalkanoate (PHA). A recombinant Ralstonia eutropha with a high PHA yield includes a promoter for upregulating a phaJ gene and further includes a mutant phaC gene. The recombinant Ralstonia eutropha can be used for producing 3-hydroxybutyrate-co-3-hydroxyhexanoate (PHBHHx) in PHA.

Abstract: The invention relates to a 2-isopropyl malate synthase, a genetically engineered bacterium for producing L-leucine and application thereof and belongs to the field of metabolic engineering. The genetically engineered bacterium is obtained by overexpressing an isopropyl malate synthase coding gene leuAM for relieving feedback inhibition by L-leucine, an acetohydroxy acid synthase coding gene ilvBNM for relieving feedback inhibition by L-isoleucine, a 3-isopropyl malate dehydrogenase coding gene leuB and a 3-isopropyl malate dehydratase coding gene leuCD in host cells. The genetically engineered bacterium for producing the L-leucine is free from nutritional deficiency, rapid in growth, short in fermentation period, high in yield and high in conversion rate.

Abstract: The invention discloses CA-4 antitumour drug, their synthetic methods and applications. The CA-4 antitumour drug are obtained by introducing an alkoxy group or a fluorine-containing alkoxy group at the 4? position of the natural product Combretastatin and modified with a functional chemical group at its 3? position. The CA-4 derivated anti-tumor drugs of the invention have inhibitory ability on two targets related to tubulin and arylsulfatase, and can be used for anti-tumor treatment.