Abstract: The present disclosure discloses an AtPPR1 gene (negative regulatory factor) for Phytophthora resistance and homologous genes thereof, involving an AtPPR1 gene and a protein encoded by the AtPPR1 gene. The AtPPR1 gene has a nucleotide sequence of SEQ ID NO:6, and the protein encoded by the AtPPR1 gene has an amino acid sequence of SEQ ID NO:7. A function of the AtPPR1 gene of the present disclosure to improve Phytophthora resistance of plants can be used for the selective breeding of Phytophthora-resistant varieties. As a new type of negative immunoregulatory factor in plants, AtPPR1 negatively regulates the resistance of plants to Phytophthora by interfering with downstream signal transduction of endogenous jasmonic acid (JA) and salicylic acid (SA) and ROS signals in plants.

Abstract: Disclosed are 3,4-methylenedioxyphenylimidazolylethanonexime ether derivatives, a preparation method and use thereof, and a drug for the treatment of Alzheimer's disease, which relates to the technical field of preparation of acetophenone oxime ether compounds. The (Z)-3,4-methylenedioxyphenylimidazolylethanonexime ether derivatives provided by the present disclosure show a significant effect on the inhibition of NO production, with an EC50 of 2.07-5.41 ?mol/L. Compared with the positive control group of quercetin (with an EC50 of 9.56 ?mol/L) and oxiconazole (with an EC50 of 13.5 ?mol/L), the inhibitory effect is stronger without significant cytotoxicity (cell viability >90%), which can be used to prepare drugs for the treatment of Alzheimer's disease.

Abstract: A steroidal piperidone derivative, a synthesis method, and a use thereof are provided. The steroidal piperidone derivative has a chemical structure shown in general formula (1) or general formula (2), where R is any one selected from the group consisting of alkyl, phenyl, substituted phenyl, and a heterocycle. In the synthesis method of the steroidal piperidone derivative, dehydroepiandrosterone (DHEA) is used as a basic raw material to prepare the steroidal piperidone derivative of the present disclosure through a series of reactions. A product prepared by the synthesis method has a high yield and is easily separated, and thus the synthesis method is the optimal method for preparing the steroidal piperidone derivative of the present disclosure. The present steroidal piperidone derivative exhibits prominent toxic activity against sucking pests, such as aphids, spider mites, rice planthoppers, and B. tabaci, and can be used for the control of a plant pest.

Abstract: A method for simulating a development date based on a response mechanism and an adaptation mechanism of a crop to an environment, including: collecting crop phenology data observed at a research station; obtaining a day of year of a start date, a quantity of days, and an average temperature, in the development phase, based on the crop phenology data; obtaining a development rate based on the quantity of days in the development phase, where the development rate is a reciprocal of the quantity of days in the development phase; calculating a product of the average temperature and the day of year of the start date of the development phase; and obtaining a regression equation as an equation simulating the development date, through a linear regression algorithm, where the development rate serves as a dependent variable, and the average temperature and the product serve as regressors.

Abstract: The present invention relates to internal combustion engines, and discloses a double-cylinder internal combustion engine. The double-cylinder internal combustion engine of the present invention adopts a curved groove ball bearing mechanism to replace crank-connecting rod mechanisms since traditional internal combustion engines have a complicated structure, high material requirements, high processing difficulty, and the inertia effect and noises thereof are hard to be eliminated. Two inner rings of the curved groove ball bearing mechanism are fixedly connected, and a valve mechanism and an ignition mechanism are driven through a gear pair, so that the two sets of cylinders and pistons reciprocate in opposite directions to automatically balance reciprocating inertia thereof. Compared with the prior art, the present invention has simple motion forms which only consist of the rotary motion and the reciprocating motion, and low noises are produced.

Abstract: A serum-free culture medium for in vitro maturation of bovine oocytes includes a Hepes-free M199 basal medium, fatty acid-free BSA, human menopausal gonadotrophin (HMG), 17?-estradiol, epidermal growth factor (EGF), L-cysteine, bFGF, Glutamax (100×), folic acid, cholic acid and CXCL12. A method of culturing bovine oocytes using such serum-free culture medium is provided.

Abstract: The present invention discloses a method for efficiently and mildly reducing ovalbumin allergenicity. The present invention promotes the exposure of the ovalbumin allergenic site to the molecular surface by repeated freezing and thawing pretreatment, and combines transglycosylase and trypsinase for synergistic treatment to reduce the ovalbumin sugar chain and epitope to achieve the purpose of significantly reducing the allergenicity of ovalbumin and egg foods. Compared with other traditional methods such as high temperature and high pressure and other physical means to reduce egg allergenicity, the method significantly improves the specificity and effectiveness of egg desensitization, and minimizes the damage to the nutrition and quality of egg proteins, and is an efficient and mild egg desensitization method. The method has the prospects of being applied to the industrial development of low-allergenicity egg products.

Abstract: The present invention discloses a method for efficiently and mildly reducing ovalbumin allergenicity. The present invention promotes the exposure of the ovalbumin allergenic site to the molecular surface by repeated freezing and thawing pretreatment, and combines transglycosylase and trypsinase for synergistic treatment to reduce the ovalbumin sugar chain and epitope to achieve the purpose of significantly reducing the allergenicity of ovalbumin and egg foods. Compared with other traditional methods such as high temperature and high pressure and other physical means to reduce egg allergenicity, the method significantly improves the specificity and effectiveness of egg desensitization, and minimizes the damage to the nutrition and quality of egg proteins, and is an efficient and mild egg desensitization method. The method has the prospects of being applied to the industrial development of low-allergenicity egg products.