Abstract: Disclosed are an offset calibration method and circuit applied to a comparator array. The offset calibration circuit includes a global calibration voltage generation module, integrators, comparators, a global logic control circuit, and local logic control circuits; an entire comparator array shares the single global calibration voltage generation module, and each of the comparators only needs to introduce an integrator circuit, such that a large calibration range and a small calibration step are achieved, a long calibration cycle and a large circuit area are required, and the requirements for a low area are satisfied. The offset calibration method provided by the present disclosure is similar to a binary search algorithm, which is adopted to search for the offset voltage, the calibration step of 1 2 N ? Vref can be realized by only N cycles, and short calibration time is thus realized.

Abstract: Disclosed is a hybridoma cell strain that secretes anti-dinitolmide monoclonal antibodies applicable to the field of food safety immunoassay methods. The hybridoma cell strain DAS3H10 that secretes anti-dinitolmide monoclonal antibodies has been deposited in Comprehensive Microbiology Center of China Microbial Culture Collection Management Committee (CGMCC), addressed in No. 1 Hospital No. 3 Institute of Microbiology of the Chinese Academy of Sciences, North Chenxi Road, Beijing Chaoyang District in Beijing. It is classified as a monoclonal cell strain. The deposit date is Nov. 28, 2019, and the deposit number is MCCC No. 19165. The monoclonal antibody secreted by the hybridoma cell strain DAS3H10 has a good affinity and high sensitivity to dinitolmide. Because of IC50 to dinitolmide up to 9.01 ng/mL, the monoclonal antibody could be used to prepare dinitolmide immunoassay kits and colloidal gold test strips, and can further provide a powerful means for detecting dinitolmide in animal-derived foods.

Abstract: Disclosed are a flexible pH sensor and detection system, belonging to the technical field of sensors. A material that does not react with electrolyte is mixed with metals to print an anode substrate, and one-step synthesis of a metal ions doped polyaniline composite material is realized through an electrochemical method. The doping amount of metal ions in polyaniline is changed by controlling metal content; due to addition of the metals, the conductivity of the anode substrate is improved, which is conducive to the deposition of polyaniline; such one-step method for preparing the polyaniline composite material is simpler, low in cost, and pollution-free; and compared with pure polyaniline, the sensitivity is further improved. According to the solution, this material is applied to the pH sensor for the first time, achieving a wide pH detection range (2-12) and high bending stability.

Abstract: The disclosure discloses a strain of Lactobacillus crispatus capable of preventing and/or treating Helicobacter pylori infection, and belongs to the technical fields of microorganisms and medicine. The disclosure provides a strain of Lactobacillus crispatus CCFM1118. The Lactobacillus crispatus CCFM1118 can inhibit Helicobacter pylori, specifically embodied in that: (1) the diameter of an inhibition zone of supernatant of the Lactobacillus crispatus CCFM1118 on Helicobacter pylori can reach 13.14 mm; and (2) the Lactobacillus crispatus CCFM1118 can significantly reduce the adhesion of Helicobacter pylori to AGS cells. Therefore, the Lactobacillus crispatus CCFM1118 has great application prospects in inhibiting Helicobacter pylori (not for the purposes of disease diagnosis and treatment) and preparing Helicobacter pylori inhibitors.

Abstract: The disclosure discloses Bifidobacterium longum with the ability to relieve atopic dermatitis and its application, and belongs to the technical fields of microorganisms and medicine. The Bifidobacterium longum of the disclosure has the effects of relieving atopic dermatitis, and the effects are specifically embodied in: (1) significantly improving the degree of ear swelling in mice with atopic dermatitis; (2) significantly improving skin pathological symptoms and inflammatory cell infiltration in mice with atopic dermatitis; (3) significantly reducing the serum IgE level in mice with atopic dermatitis; (4) significantly reducing the levels of IL-4 and IL-13 in the skin tissues of mice with atopic dermatitis; and (5) significantly reducing the level of histamine in the skin tissues of mice with atopic dermatitis. Therefore, the Bifidobacterium longum has great application prospects in the preparation of products for the prevention and/or treatment of atopic dermatitis.

Abstract: The present disclosure provides a method for preparing concentrated high-protein yogurt before fermentation, belonging to the technical field of dairy product processing. The method for preparing the concentrated high-protein yogurt before fermentation in the present disclosure includes: enabling a high-protein base material with a decalcification rate of 21.8-44.2% to be subjected to heat treatment at pH of 6.6-6.8 and temperature of 80-95° C. for 10-30 min; after that, cooling to 40-45° C., adding 0.05-0.2% (w/w) of a starter, and carrying out high end-point pH fermentation at 40-45° C. until the pH drops to 4.8-5.0; and then, performing low-temperature after-ripening to obtain the high-protein yogurt. Compared with high-protein yogurt prepared by a whey discharge process after fermentation, the concentrated high-protein yogurt prepared according to the present disclosure has similar or better soft texture, delicate taste, water holding capacity and digestibility, and is higher in calcium content.

Abstract: The present invention discloses a RamA transcription factor mutant for promoting the production of N-acetylglucosamine and use thereof. The mutant is obtained by mutating lysine at position 90 to asparagine and serine at position 92 to lysine in a parent having an amino acid sequence as shown in SEQ ID NO: 2. The present invention provides a genetically engineered strain that overexpresses the RamA transcription factor mutant and increases the production of N-acetylglucosamine. By overexpressing the transcription factor RamA that is involved in the regulation of carbon metabolism, the extracellular accumulation of N-acetylglucosamine is increased, with a maximum concentration reaching 31.5 g/L, which lays a foundation for further metabolic engineering of Corynebacterium glutamicum to produce glucosamine. The method for constructing recombinant Corynebacterium glutamicum of the invention is simple, and convenient in use, and thus has good application prospects.

Abstract: The disclosure discloses a strain of Lactobacillus rhamnosus and application thereof in inhibiting Helicobacter pylori, and belongs to the technical fields of microorganisms and medicine. The disclosure provides a strain of Lactobacillus rhamnosus CCFM1119. The Lactobacillus rhamnosus CCFM1119 can prevent and/or treat Helicobacter pylori infection, specifically embodied in that: (1) the Lactobacillus rhamnosus CCFM1119 can significantly relieve the gastrointestinal symptoms of patients with Helicobacter pylori infection; (2) the Lactobacillus rhamnosus CCFM1119 can significantly reduce the amount of colonization of Helicobacter pylori in patients with Helicobacter pylori infection; and (3) the Lactobacillus rhamnosus CCFM1119 can significantly increase the clearance rate of Helicobacter pylori in patients with Helicobacter pylori infection.

Abstract: The disclosure discloses a method for increasing the intracellular heme content of Escherichia coli and belongs to the field of metabolic engineering. In the disclosure, in E. coli, the gene mscS encoding a small conductance mechanically sensitive ion channel protein is knocked out, the gene aroG encoding 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase is knocked out, or the gene hemA encoding glutamyl-tRNA reductase is overexpressed. The constructed recombinant strain is cultured in an LB culture medium, and the heme content can reach 47.6 ?mol·L?1, which is significantly higher than that of a control strain. The recombinant strain has the value of wide application.

Abstract: A method for preparing a sustained-release antibacterial film includes: (1) mixing a cyclodextrin metal-organic framework (CD-MOF) material with a silver nitrate short-chain alcohol solution to prepare an intermediate material A; (2) mixing the intermediate material A with a caffeic acid short-chain alcohol solution to prepare an intermediate material B; (3) dispersing the intermediate material B in a solvent, adding a polydimethylsiloxane main agent and a PDMS auxiliary agent in sequence, and mixing well by stirring to obtain a casting solution; and (4) coating the casting solution on a film support material, conducting vacuum drying, and peeling off a film from the film support material to obtain the sustained-release antibacterial film. A mixed matrix-based film material in which the CD-MOF and the PDMS are physically blended is prepared based on CD-MOF and PDMS for the first time, and may be used in application researches of food, environment and other fields.

Abstract: The disclosure discloses a feruloyl esterase and application thereof, and belongs to the technical field of microorganisms. The disclosure provides a feruloyl esterase with an amino acid sequence shown in SEQ ID NO: 2 and specific enzyme activity as high as 519 U/g. The disclosure provides a recombinant Bacillus subtilis which uses Bacillus subtilis as a host, expresses a gene encoding the feruloyl esterase with an amino acid sequence shown in SEQ ID NO: 2, and can be used for producing the feruloyl esterase with a high yield. The process specifically includes inoculating a fermentation culture medium with the recombinant Bacillus subtilis for fermentation for 14 hours, and the enzyme activity of the feruloyl esterase in a cell disruption supernatant can be as high as 82.53 U/mL.

Abstract: The present disclosure discloses a preparation method of fatty acid-based VC liposomes, and belongs to the field of pharmaceutical preparations. In the disclosure, a complex of industrial conjugated linoleic acid and other fatty acids with sodium dodecyl sulfate is taken as a capsule material, which is self-assembled to embed vitamin C in an aqueous phase under an acidic condition (pH<7) to form the fatty acid-based vitamin C liposome. The preparation method of the disclosure does not use organic solvents and other substances harmful to the human body, and has the characteristics of safety and health. In addition to VC encapsulation under the acidic condition, the prepared fatty acid-based liposome can play a role in slowly releasing VC.

Abstract: The disclosure discloses a fusion albumin nanoparticle and application thereof, and belongs to the technical field of biomedicine. In the disclosure, fusion albumin is expressed by using a genetic engineering technology, and the fusion albumin nanoparticle is formed by performing self-assembly and drug loading on the fusion albumin in a neutral aqueous solution. The fusion albumin studied in the disclosure has targetability, pH and enzyme-sensitive functional groups, the nanoparticle prepared by using the fusion albumin has the functions of targetability and controlled drug release, and a method for preparing the fusion albumin nanoparticle is simple and easy to implement and has great application potential.

Abstract: Disclosed are a water-soluble chlorhexidine antimicrobial agent and a preparation method therefor and use thereof. The present disclosure takes hyaluronic acid as a raw material to prepare a hyaluronic acid aqueous solution or organic solution, then the hyaluronic acid aqueous solution or organic solution and a chlorhexidine solution are subjected to a complexation reaction, an insoluble substance therein is removed, and then the resulting solution is dried to obtain the water-soluble chlorhexidine antimicrobial agent, namely hyaluronic acid chlorhexidine. The hyaluronic acid chlorhexidine has a good broad-spectrum antimicrobial performance, and excellent water solubility.

Abstract: The invention provides a method for constructing a target prediction model in a multicenter small sample scenario and a prediction method. In combination with the idea of transfer learning, a training set of a new node is predicted by directly using knowledge of a trained node, and a prediction error sample is used to reflect a difference between the new node and the trained node. The difference is used as supplementary knowledge. Model knowledge of the new node is quickly acquired, to avoid training of a new node from scratch each time. Finally, parallel integration of incremental subclassifiers is implemented by using a ridge regression method, so that the deployment time and costs are greatly reduced. The generalization of models is ensured through sharing of historical knowledge and a knowledge discarding mechanism, good classification effect can also be achieved for a node with a small sample size.

Abstract: A hybridoma cell line of secreting cyproheptadine monoclonal antibodies with a preservation number of CGMCC No. 14699 belongs to the field of food safety immunological detection. BALB/c mice are immunized through one time immunization with complete freund's adjuvant, three times of booster immunization with incomplete freund's adjuvant and one time of rush immunization with cyproheptadine complete antigen without adjuvant; the spleen cells from BALB/C mice immunized with high potency and low value of IC50 are fused with murine myeloma cells; and then the hybridoma cell line is obtained through indirect competitive ELISA screening and three sub-clones. The monoclonal antibody secreted by this cell line has good specificity and detection sensitivity to cyproheptadine (value of IC50 is 0.37 ng/ml), being suitable for detection of cyproheptadine in food.

Abstract: The present invention provides a method for promoting N-acetylglucosamine synthesis by using the GlcN6P responsive element. In the present invention, Bacillus subtilis BSGNY-Pveg-glmS-P43-GNA1 is used as a starting strain, in which a CRISPRi system regulated by GlcN6P responsive element is integrated into the genome to dynamically weaken the N-acetylglucosamine synthesis competitive pathway; a GlcN6P responsive promoter is used to regulate the expression of GNA1 on the plasmid to dynamically regulate the N-acetylglucosamine synthesis pathway; and the key gene alsSD involved in the acetoin synthesis pathway is knocked out. During fed-batch fermentation with this strain in a 15 L fermenter, the production of N-acetylglucosamine reaches 131.6 g/L and no by-product acetoin is accumulated, which lays a foundation for the production of GlcNAc by industrial fermentation.

Abstract: Disclosed are self-aspirating and gas-liquid dispersing impellers, belonging to the technical field of impellers. The self-aspirating and gas-liquid dispersing impellers include an stirring shaft, a hub, a disc and blades; the hub is coaxially sleeved on the stirring shaft, the disc is connected to the hub, a plurality of blades which extend in the radial direction are arranged on the circumferential side face of the disc, and a gas inlet channel is formed in the disc; each of the plurality of blades includes an upper curved surface and a lower curved surface, and a rotary cavity is embedded between the upper curved surface and the corresponding lower curved surface; and one side of the rotary cavity is a liquid facing surface. The impeller of the disclosure has the dual functions of radial gas-liquid dispersing and axial fluid mixing, effectively promotes microscopic mass transfer and macroscopic fluid delivery between gas and liquid phases.

Abstract: The present disclosure discloses a method for modification of mung bean protein and preparation of simulated egg pulp based on the modified protein. A commercial mung bean protein isolate is used as a raw material in the present disclosure, then subjected to pH shift modification, ultrasonic treatment and protein-glutaminase treatment for compound modification to prepare a high-functionality modified mung bean protein isolate; and the modified mung bean protein isolate is used as a raw material, using high-speed emulsification and high-pressure homogenization are conducted to obtain a high-stability mung bean protein-based simulated egg pulp. In the present disclosure, the mung bean protein isolate prepared by compound modification has good solubility, emulsifying property and gelling property. The mung bean protein-based simulated egg pulp is in the form of a stable emulsion and has good fluidity and moderate gelling property, and uniformity and stability can still be maintained for a long time.

Abstract: The disclosure discloses a nicotinamide dummy template surface molecularly imprinted polymer, a preparation method and application thereof, and belongs to the technical field of chemical materials. The preparation method of the disclosure includes the steps of preparing a modified silica gel carrier, preparing a dummy template surface molecularly imprinted polymer and the like. The disclosure uses nicotinamide, a structural analogue of imidacloprid and acetamiprid, as a dummy template to prepare a silica gel surface molecularly imprinted polymer. The polymer not only can effectively avoid pollution caused by the leakage of template molecules, but also can specifically remove imidacloprid and acetamiprid from water-soluble tea extracts. The removal rate of imidacloprid and acetamiprid is greater than 96% and 93%, respectively, and the loss of tea polyphenols in the extracts is less than 10%.