37 results about "Heavy ion radiation" patented technology

The invention discloses a method for verifying a single particle soft error protection design based on a heavy ion accelerator, and relates to the field of heavy ion and proton equivalent test verification of system single particle protection effect verification based on accelerator test data. The method includes the following steps: (1) adopting a ground accelerator heavy ion test which is determined on the basis of a LET value; (2) analyzing a proton static overturning cross section; (3) analyzing a sensitive bit factor of the system under any working mode; (4) analyzing a dynamic overturning cross section of the system under heavy ion radiation; (5) analyzing a dynamic overturning cross section of the system under proton radiation. The invention provides a method for verifying a single particle soft error protection design based on the heavy ion accelerator. The method can be intended for verifying single particle protection effects, and address the problems of tight time of domestic accelerators and difficulty in realizing high energy proton tests.

The invention discloses a proton and heavy ion dose calculation method under a magnetic field based on a GPU Monte-Carlo method. The method comprises the following steps: 1) collecting data; 2) determining an optimal thread count and transport task batches of a GPU; 3) calculating proton and heavy ion radiation dose of each batch under the magnetic field by utilizing the Monte-Carlo method; 4) calculating radiation dose of secondary particles of each batch under the magnetic field by utilizing the Monte-Carlo method; and 5) summarizing dose results based on a GPU fast atom addition method. The method can quickly and accurately calculate the proton and heavy ion radiation dose under the action of the magnetic field, and can be used for dose calculation of an MRI real-time guided proton and heavy ion treatment planning system, thereby improving accuracy and speed of dose calculation in the treatment planning system, and improving radiation treatment effect.

The invention relates to a positioning and verification method for radiation therapy of tumors. The method consists of a radiation therapy field positioning method and a multileaf collimator shape verification method. The radiation therapy field positioning method comprises the following steps of (1) marking the position of a field center cross on the body surface of a patient; (2) making the center cross of the visual field of a camera in a positioning and verification device for radiation therapy of tumors and the therapy field central axis coincide; (3) showing the shooting field of the camera on a displayer in real time; (4) making the center cross of the visual field and the field center cross on the body surface of the patient coincide; and (5) completing the positioning, and making the camera return to the initial position on a guide rail. The multileaf collimator shape verification method comprises the following steps of: performing the steps of (1) to (4) in the radiation therapy field positioning method; (5) obtaining a corresponding ratio on the optical grating distance of a multileaf collimator; (6) displaying a radiation field shape or virtual multileaf collimator shape of the patient in the visual field of the camera, and making the center of the radiation field shape or virtual multileaf collimator shape of the camera coincide with the center of the visual field of the camera; (7) forming a heavy ion radiation field shape; and (8) completing the multileaf collimator shape verification. The method is simple and convenient.

The invention relates to a method for screening biomarkers of ionizing radiation as well as an application of SZT2 protein determined by the method to preparation of a molecular biomarker kit for personnel exposed to heavy ion radiation. The method comprises the following steps: screening differentially expressed genes in human cells which are treated with heavy ion irradiation by using a genechip method; screening differentially expressed proteins in cells of the same type which are treated with heavy ion irradiation by using iTRAQ technology; comparing screening results, and from the genes and the proteins which are differentially expressed simultaneously, selecting differentially expressed protein SZT2 which is down-regulated both in gene and protein levels as the biomarker of ionizing radiation. The genechip method and iTRAQ technology are combined, categories and quantities of genes and proteins in cell specimens of experimental groups of different dosages and a control group are compared and analyzed, the differentially expressed protein SZT2 which is down-regulated both in gene and protein levels can be rapidly found, and the protein can be used as a significant biomarker of ionizing radiation.

The invention discloses a novel kelp heavy ion radiation mutation breeding method. The novel kelp heavy ion radiation mutation breeding method comprises the following steps: dispersing and filtering a kelp gametophyte cloning cell system to each gametophyte cell segment composed of 1-3 gametophyte cells; radiating by using 12C heavy ions; breeding a sporophore by using a kelp gametophyte cloning breeding technology; after the sporophore is ripen, carrying out phenotype and quality character determination; carrying out DNA (Deoxyribonucleic Acid) variation detection on candidate plants with a large forward direction variation range; obviously improving phenotype and quality characters and taking the plants with obviously-varied DNA structures as breeding materials for breeding new varieties. The novel kelp heavy ion radiation mutation breeding method has the advantages that a lot of variation can be generated by radiating and inducing kelp gametophytes by the heavy ions; the variant plants can be obtained in shorter time and a new gene pool related with the good property is preserved.

The invention relates to to a high-nitrogen yeast (particularly referring to Saccharomyces cerevisiae) and a preparation method thereof. Saccharomyces cerevisiae is preserved in China General Microbiological Culture Collection Center (CGMCC) with the preservation number of CGMCC No.5004; and Saccharomyces cerevisiae is obtained by heavy ion radiation mutation, the content of nitrogen in Saccharomyces cerevisiae is 40-60%. A heavy ion mutation technology has the following main advantages that (1) variation rate is high, generally 1000 times higher than natural variation rate; (2) variation spectrum is wide, namely type of variation is diverse, and a new type of microbe strain can be obtained; (3) variation stability is strong, relatively stable strains (coexistence of positive and negative mutations) can be obtained, and screening period can be shortened; and (4) mutation operability is strong, and the radiation mutation of the microbe can be easily completed.

The invention relates to application of an ABCG1 gene as a molecular marker to preparation of a reagent for diagnosis of exposure to heavy ion radiation, belonging to the field of application of genetic molecular markers. As the ABCG1 gene is used as the molecular marker for detection of exposure to heavy ion radiation, detection is more convenient and accurate and a radiation dose can be determined.

The invention relates to a preparation method of sea cucumber polysaccharides, particularly a membrane separation method of sea cucumber polysaccharide fragments acting on simulation space heavy ion radiation oxidation stress. The method solves the problems of low sea cucumber polysaccharide extraction rate, indefinite active sites and complex production technique in the existing traditional process. The method comprises the following steps: drying fresh sea cucumbers and taking dry sea cucumbers, pulverizing, extracting in a high-voltage pulse electric field, separating the extracting solution by an ultracentrifuge, carrying out membrane separation on the polysaccharide fragments through a plate-frame membrane component, screening the effective fragments through in-vivo and in-vitro experiments, carrying out vacuum scraper membrane concentration, and carrying out freeze-drying by using a vacuum freeze drier, thereby obtaining the sea cucumber polysaccharide fragment powder acting on simulation space heavy ion radiation oxidation stress. The sea cucumber polysaccharide fragments acting on simulation space heavy ion radiation oxidation stress are a natural extract with no side effects on the human body, have the effects of resisting oxidation, enhancing the immunity and the like, and are suitable for astronauts, air force soldiers, radar soldiers, chemoradiotherapeutic tumor patients and people with hypoimmunity. The sea cucumber polysaccharide fragments acting on simulation space heavy ion radiation oxidation stress are applicable to the fields of food, health products, cosmetics, medicine, biochemical engineering and the like.

The invention discloses an efficient marking method for heavy ion radiation mouseearcress genome target spots, and relates to the field of heavy ion plant radiation induction breeding mechanism research. In order to solve the problem that an existing reporter gene has defects for marking heavy ion radiation plant genome target spots, the method comprises the steps that a mouseearcress homologous recombination report system is adopted as an experimental material, the heavy ion radiation plant genome target spots are efficiently marked in the mode that the activity of the reporter gene is recovered after the reporter gene is damaged by DNA dual-chain breakage and subjected to homologous recombination repair, red recombination fragment and a flanking genome sequence thereof are amplified through PCR high fidelity, the sequencing detection amplification sequence basic group mutation condition is cloned, and therefore the heavy ion radiation plant genome target spots are marked. The methodhas the advantages that experiment operations are easy, the marking efficiency is high, and specific induction of DNA dual-chain breakage is achieved.

The invention relates to application of genistein in the preparation of a heavy ion radiation-sensitizing drug. Effective concentration of the genistein as a radiation-sensitizing drug in the preparation of a heavy ion radiation-sensitizing drug for inhibiting tumor proliferation of patients is 5-20 microns. The drug can remarkably inhibit heavy ion radiation induced DNA double-strand break repairand promote tumor cell apoptosis so as to further raise tumor cell killing efficiency of heavy ions, has potential application value in the preparation of a radiosensitivity drug, and is helpful forenhancing the effect of single irradiation in heavy ion treatment, reducing the number of treatment, shortening treatment course and lowering treatment cost.

The invention discloses a device for measuring the exposure of rice seed embryos to heavy ion radiation. The device is a seed box for study of rice seed space radiation effect. The device consists ofan upper cover plate (3), a nuclear track detector (4), a matrix (6) and a lower cover plate (7) from top to bottom in order, the matrix (6) is a square groove equipped with a plurality of ellipticalholes (5), the elliptical holes (5) are through-holes and are used for installing and fixing rice seeds (8), the nuclear track detector (4) is installed in the square groove, and is fixed through theupper cover plate (3) and the lower cover plate (7). Based on the device, the invention also discloses a method for measuring the exposure of rice seed embryos to heavy ion radiation, and the method can acquire the linear energy transfer information of heavy ion radiation to the seed embryos. The method provided by the invention can accurately acquire the heavy ion radiation to the seed embryos, in addition to high energy and long-range heavy ions, the heavy ions also include low energy and short-range heavy ions.

The invention specifically relates to a method for increasing the starch yield of duckweed mutants through induced mutation by heavy ion radiation. Duckweed is an ideal plant material for starch production. In order to further improve the starch production efficiency of duckweed, the invention provides a method for increasing the starch yield of duckweed mutants through induced mutation by heavy ion radiation. The method comprises the specific steps: performing induced mutation on duckweed callus through heavy ion radiation, performing differentiation culture so as to obtain regenerated plants, screening plants with high-yield starch, and performing combination with certain culture conditions so as to achieve further increase of the starch yield. The starch yield of one mutant with a goodeffect is significantly increased compared to the starch yield of a control group. As an energy plant, the accumulation amount of biomass is crucial for production of bioethanol, the mass per mutant is increased by 13.5% compared with the mass of a wild type, and the biomass per unit area is increased by 74.0% compared with that of the wild type; and the mutants which are obtained by using the method have good genetic stability of traits, and are ideal engineering strains for production of bio-energy.