Abstract: Synchronous rectification control circuit and switching power supply system are provided. The circuit includes a sampling circuit, a turn-on comparison circuit, a turn-off comparison circuit, a drive control circuit, an anti-accidental turn-on circuit, wherein the sampling circuit has a first terminal coupled to a first output terminal of a transformer; the anti-accidental turn-on circuit has a first input terminal coupled to a second terminal of the sampling circuit; the turn-on comparison circuit has a first input terminal coupled to the second terminal of the sampling circuit, a second input terminal coupled to an output terminal of the anti-accidental turn-on circuit; the turn-off comparison circuit has an input terminal coupled to the second terminal of the sampling circuit; the drive control circuit has a first input terminal coupled to an output terminal of the turn-on comparison circuit, a second input terminal coupled to an output terminal of the turn-off comparison circuit.

Abstract: The present disclosure discloses a method for preparation of derivatives of gram-positive bacteria surface capsular polysaccharide, and belongs to the field of carbohydrate chemistry. The present disclosure takes glucose as a glycosyl donor to obtain a target ?-glucosidic bond, then successfully synthesizes a disaccharide building block through a method of redox of a glucose C-2 site, and then takes the disaccharide building block as a repeat unit to synthesize a target oligosaccharide structure such as a derivative [?3)-?-D-Manp-(1?4)-?-D-Rhap-(1?]5-Linker of gram-positive bacteria cell wall capsular polysaccharide. A reduction end of decose is linked with a linker to be linked with a protein to make glycoconjugates for immunological studies. The method provided by the present disclosure is simple, time-saving, labor-saving and low-cost, and the resultant derivatives of the gram-positive bacteria surface capsular polysaccharide may be used for development and preparation of medicine related to autism.

Abstract: Disclosed is synthesis of an O-Antigen oligosaccharide compound of Helicobacter pylori serotype O2, belonging to the field of organic synthesis. The disclosure obtains O-antigen disaccharide to tetracosasaccharide of Helicobacter pylori serotype O2 by chemical synthesis. A chemical synthesis method which is quite conducive to production of a glucose-?-lglucosidic bond is developed in the disclosure by a protectant strategy, temperature effect, solvent effect, and additive effect. The method is applied in synthesis of an O-antigen oligosaccharide compound of Helicobacter pylori serotype O2 assembled with an amino linking arm. A saccharide conjugate can be prepared from the synthesized O-antigen oligosaccharide compound of Helicobacter pylori serotype O2 assembled with an amino linking arm together with a carrier protein for immunology researches, playing an important role in preventing and treating Helicobacter pylori.

Abstract: The present invention relates to a composition comprises at least one random copolymer having at least one repeat unit of structure (1), The present invention also relates to novel processes for forming patterns using this novel crosslinked layer on a substrate by enable a film of a block copolymer coated on the novel crosslinked layer to undergo self-assembly.

Abstract: The present disclosure discloses a crosslinked hydrogel for muscle stem cell culture and a preparation method and use thereof, and belongs to the technical field of biological food materials. The preparation method includes: dissolving collagen to prepare a solution and adding a certain amount of alginate and heparan sulfate proteoglycan for being uniformly mixed with the collagen solution; and adding ?-PL and TGase into the solution, uniformly stirring, and putting a slurry into a mold for crosslinking to obtain the hydrogel. The hydrogel is prepared by linking the collagen, the polylysine and the heparan sulfate proteoglycan using the TGase to form covalent crosslinking, and forming a compact three-dimensional “egg box” network structure through a physical electrostatic interaction between the polylysine and the alginate. The hydrogel can enhance the absorption to nutrient substances by the muscle stem cells and facilitate the growth of the muscle stem cells.

Abstract: The present disclosure discloses a preparation method and use of a crosslinked hydrogel for muscle stem cell culture, and belongs to the technical field of biological food materials. Chitosan, alginate, dextran and Ca2+ are crosslinked through physical crosslinking to form a double-network hydrogel with a high mechanical strength, the hydrogel is coated with heparin and collagen through dip coating, such that the hydrogel can immobilize growth factors and adhere to cells. Meanwhile, extracted primary muscle stem cells are inoculated onto the hydrogel and cultured in a growth medium (79% of DMEM, 10% of FBS and 1% of double antibodies) for 24 h. The cells are cultured in an incubator with a differential medium (97% of DMEM, 2% of horse serum and 1% of double antibodies) for 7 d. The hydrogel can enhance the absorption to nutrient substances by the muscle stem cells and facilitate growth of the muscle stem cells.

Abstract: A linear asymmetric method for examining branch-outage-type steady-state security of AC power networks is provided. Two linear expressions of bus injection active and reactive powers in terms of translation voltages and voltage angles of all buses are established. Then a linear asymmetric matrix-equation model for the steady state of the network is built considering the reference bus number. Manipulating this model produces the matrix expression of branch-not-outage-type translation voltages and voltage angles of non-reference buses and the bus impedance matrix with the reference bus discarded. The branch-outage-type translation-voltage increments and voltage-angle increments of non-reference buses are then obtained by the bus impedance matrix and the outage branch using the calculation formula of ordinary inverse of a modified matrix. The examination of the steady-state security of the network is achieved using these increments.

Abstract: The present disclosure discloses preparation and application of a novel multifunctional nanocomposite material with new photosensitizer, and belongs to the technical field of photodynamic therapy and the field of biomedicine. The photosensitizer multifunctional nanocomposite material provided by the present disclosure is prepared by self-assembly of cercosporin and an acid-sensitive copolymer multifunctional material with liver tumor cell targeting ability and traceability, wherein the acid-sensitive copolymer multifunctional material can be a copolymer of poly(N,N-dimethylaminoethyl methacrylate) and poly-3-azido-2-hydroxypropyl methacrylate covalently linked by galactose-modified rhodamine B.

Abstract: A power semiconductor package comprises a lead frame, a low side field-effect transistor (FET), a high side FET, a capacitor, a resistor, an inductor assembly, a first plurality of bonding wires, and a molding encapsulation. In one example, an entirety of the inductor assembly is disposed at a position higher than an entirety of the low side FET, higher than an entirety of the high side FET, and higher than an entirety of the first plurality of bonding wires. In another example, a bottom surface of the low side FET and a bottom surface of the inductor assembly are co-planar.

Abstract: A multi-function switch has a Junction-Field Effect Transistor (JFET) that outputs a voltage for both charging and timing/sense the synchronous rectifier controller. Current is provided to a synchronous rectifier controller from a JET having its drain conductively coupled to the drain electrode of the secondary side rectifying MOSFET, wherein the current from the source of the JET is used for both timing/sense and powering the synchronous rectifier controller. The JFET is biased for a fixed output with its source to gate voltage at a turn on threshold voltage of the JFET for charging. The JFET is fully conducting from the secondary side of transformer with a small voltage drop across the drain to source electrode of the secondary side rectifying MOSFET for timing/sense.

Abstract: The present invention relates to resist compositions comprising a polymer component, a photoacid generator component (PAG), a photoactive diazonaphthoquinone component (PAC), a base component, a solvent component, and optionally, a heterocyclic thiol component. The polymer component is a Novolak derivative, comprising Novolak repeat units with free phenolic hydroxy moieties, and Novolak repeat units comprising phenolic hydroxy moieties protected with an acid cleavable acetal moiety.

Abstract: Disclosed is the application of heptoglycan-chain-containing oligosaccharide compounds in preparation of a vaccine against Helicobacter pylori, belonging to the field of medicine. Different antigen oligosaccharides were obtained by chemical synthesis and fixed onto a chip surface to prepare a synthetic oligosaccharide chip. With animal immunization experiments and synthetic oligosaccharide chip analysis, the antibodies in antiserum produced by Helicobacter pylori polysaccharide immunization are used to determine the structure-activity relationship between the synthetic oligosaccharides and immunogenicity. It is found that the heptoglycan chain in the oligosaccharide compounds is an important immune epitope, and oligosaccharides containing ?-(1?3) heptoglycan chain can be used in preparation and development of vaccines for prevention and treatment of Helicobacter pylori infection.

Abstract: Disclosed is a method for synthesizing an 0-antigen saccharide chain of Helicobacter pylori serotype O:6 using seven glycosylation building blocks. Inexpensive and easily available D-glucosamine, D-galactose, D-mannose and L-fucose are used as starting materials, and seven glycosylation building blocks are obtained through a series of chemical reactions. The saccharide building blocks are then selectively linked together to produce O-antigen oligosaccharide chains of Helicobacter pylori serotype O:6 with different saccharide configuration through a series of glycosylation reactions. Also disclosed is a method to assemble an amino linker at the reducing end of the O-antigen saccharide chain of Helicobacter pylori serotype O:6, and the synthesized oligosaccharide chain with an amino linker can be coupled to a carrier molecule or immobilized on a matrix.

Abstract: The disclosure discloses a glyco-metal-organic frameworks-based hepatic targeted therapeutic drug and a preparation method thereof, and belongs to the field of biomedicine. The disclosure loads a chemotherapeutic drug onto specific metal-organic frameworks, and modifies targeted molecule galactose on the surface of the materials through amide reaction. The biocompatibility and cytotoxicity of the obtained hepatic targeted therapeutic drug have been carefully evaluated at the cellular level. The hepatic targeted therapeutic drug of the disclosure has good stability and acidic pH triggered drug release property, and can exert the synergistic therapeutic effect of photodynamic therapy and chemotherapy. In addition, in vivo behavioral tracing and therapeutic efficacy are evaluated in mouse models with subcutaneous solid tumor and tumor in situ, and the disclosure is expected to play a huge role in clinical applications.

Abstract: A multi-function switch has a Junction-Field Effect Transistor (JFET) that outputs a voltage for both charging and timing/sense the synchronous rectifier controller. Current is provided to a synchronous rectifier controller from a JET having its drain conductively coupled to the drain electrode of the secondary side rectifying MOSFET, wherein the current from the source of the JET is used for both timing/sense and powering the synchronous rectifier controller. The JFET is biased for a fixed output with its source to gate voltage at a turn on threshold voltage of the JFET for charging. The JFET is fully conducting from the secondary side of transformer with a small voltage drop across the drain to source electrode of the secondary side rectifying MOSFET for timing/sense.

Abstract: A linear asymmetric method for examining branch-outage-type steady-state security of AC power networks is provided. Two linear expressions of bus injection active and reactive powers in terms of translation voltages and voltage angles of all buses are established. Then a linear asymmetric matrix-equation model for the steady state of the network is built considering the reference bus number. Manipulating this model produces the matrix expression of branch-not-outage-type translation voltages and voltage angles of non-reference buses and the bus impedance matrix with the reference bus discarded. The branch-outage-type translation-voltage increments and voltage-angle increments of non-reference buses are then obtained by the bus impedance matrix and the outage branch using the calculation formula of ordinary inverse of a modified matrix. The examination of the steady-state security of the network is achieved using these increments.

Abstract: A power semiconductor package comprises a lead frame, a low side field-effect transistor (FET), a high side FET, a capacitor, a resistor, an inductor assembly, a first plurality of bonding wires, and a molding encapsulation. In one example, an entirety of the inductor assembly is disposed at a position higher than an entirety of the low side FET, higher than an entirety of the high side FET, and higher than an entirety of the first plurality of bonding wires. In another example, a bottom surface of the low side FET and a bottom surface of the inductor assembly are co-planar.

Abstract: The present invention provides light-emitting devices with improved quantum efficiency. The light emitting diode structure comprising: a p-doped layer an n-doped layer; and a multiple quantum well structure sandwiched between the p-doped layer and n-doped layer, wherein the multiple quantum well structure comprising a quantum well disposed between n-doped barrier layers.

Abstract: The present disclosure discloses a method for preparation of derivatives of gram-positive bacteria surface capsular polysaccharide, and belongs to the field of carbohydrate chemistry. The present disclosure takes glucose as a glycosyl donor to obtain a target ?-glucosidic bond, then successfully synthesizes a disaccharide building block through a method of redox of a glucose C-2 site, and then takes the disaccharide building block as a repeat unit to synthesize a target oligosaccharide structure such as a derivative [?3)-?-D-Manp-(1?4)-?-D-Rhap-(1?]5-Linker of gram-positive bacteria cell wall capsular polysaccharide. A reduction end of decose is linked with a linker to be linked with a protein to make glycoconjugates for immunological studies. The method provided by the present disclosure is simple, time-saving, labor-saving and low-cost, and the resultant derivatives of the gram-positive bacteria surface capsular polysaccharide may be used for development and preparation of medicine related to autism.

Abstract: The disclosure discloses a chemical synthesis method of oligosaccharides of a Pseudomonas aeruginosa serotype O11 O-antigen, and belongs to the field of chemistry. The disclosure includes constructing an O-antigen trisaccharide by using a D-glucose building block, an L-fucosamine building block and a D-fucosamine building block; wherein the D-glucose building block or the L-fucosamine building block is linked with the D-fucosamine building block through a 1,2-?-cis-glycosidic bond, the D-glucose building block is linked with the L-fucosamine building block through a 1,2-?-trans-glycosidic bond, and the construction of the 1,2-?-cis-glycosidic bond is conducted in a mixed solvent; and the mixed solvent includes two or more of dichloromethane, diethyl ether and thiophene.