为研究快中子照相技术(FNR)在武器质量检测中的可行性,以公开的武器模型数据建立模拟模型,利用Monte Carlo(MC)方法对快中子照相在武器质量检测中的安全性进行评估,由评估数据得出在14.1 Me V快中子累计照射2×10~8n条件下,铀、钚...为研究快中子照相技术(FNR)在武器质量检测中的可行性,以公开的武器模型数据建立模拟模型,利用Monte Carlo(MC)方法对快中子照相在武器质量检测中的安全性进行评估,由评估数据得出在14.1 Me V快中子累计照射2×10~8n条件下,铀、钚两种裂变材料损伤极小。同时,参考国外研究模型和预设缺陷,设计加工了类比模型实验样品,通过实验和模拟相结合的方式对武器检测中可能出现的内部狭缝、圆孔和中心位移等问题进行研究。实验结果表明FNR可以识别5 mm钢包裹条件下的1 mm的狭缝缺陷。模拟结果显示FNR可以实现对特定厚度的特殊材料进行中心位移缺陷诊断,模拟评估和实验结果表明快中子照相技术在武器质量检测中具有可行性。展开更多
Calpastatin is an endogenous inhibitor of calpain which is responsible for the breakdown of myofibrillar proteins, The association of Single Nucleotide Polymorphism （SNP） in the calpastatin gene with meat tenderness...Calpastatin is an endogenous inhibitor of calpain which is responsible for the breakdown of myofibrillar proteins, The association of Single Nucleotide Polymorphism （SNP） in the calpastatin gene with meat tenderness is an important topic in meat production. Therefore efficient procedure to investigate the SNP is necessary. The objectives of this study were to detect the SNP of calpastatin gene at domain L marker （G/C transversion） of the Kamphaengsaen beef breed （KPS cattle; n = 26） by the Amplification Refractory Mutation System （ARMS） compared with the Restriction Fragment Length Polymorphism （RFLP） methods and to determine the genotypes of the KPS cattle at that marker. Genomic DNA of calpastatin gene extracted from blood of the KPS cattle was detected with ARMS and RFLP methods. The ARMS system has utilized two primer pairs to amplify the two different alleles of a polymorphism in single PCR reaction to detected single base mutation. In this method, the alleles-specific primers had a mismatch at 3＇ terminal base and a second deliberate mismatch at position -2 from 3＇ terminus. While the RFLP method detected a polymorphism using PCR-base technique follow by RsaI restriction enzyme. Amplification of the ARMS method revealed that the results were not different from the conventional method of RFLP. Analysis of genotypes revealed that the KPS cattle inherited the CC, CG and GG genotypes at domain L marker. These were reliable when verified by nucleotide sequence analysis of PCR products. The animals were genotyped and determined for tenderness phenotype with this marker that predicted variation of an intronic polymorphism at domain L of the calpastatin gene. Therefore, the ARMS method was simple, efficient technique, and suitable for detecting SNP at domain L marker of the calpastatin gene.展开更多
文摘Calpastatin is an endogenous inhibitor of calpain which is responsible for the breakdown of myofibrillar proteins, The association of Single Nucleotide Polymorphism （SNP） in the calpastatin gene with meat tenderness is an important topic in meat production. Therefore efficient procedure to investigate the SNP is necessary. The objectives of this study were to detect the SNP of calpastatin gene at domain L marker （G/C transversion） of the Kamphaengsaen beef breed （KPS cattle; n = 26） by the Amplification Refractory Mutation System （ARMS） compared with the Restriction Fragment Length Polymorphism （RFLP） methods and to determine the genotypes of the KPS cattle at that marker. Genomic DNA of calpastatin gene extracted from blood of the KPS cattle was detected with ARMS and RFLP methods. The ARMS system has utilized two primer pairs to amplify the two different alleles of a polymorphism in single PCR reaction to detected single base mutation. In this method, the alleles-specific primers had a mismatch at 3＇ terminal base and a second deliberate mismatch at position -2 from 3＇ terminus. While the RFLP method detected a polymorphism using PCR-base technique follow by RsaI restriction enzyme. Amplification of the ARMS method revealed that the results were not different from the conventional method of RFLP. Analysis of genotypes revealed that the KPS cattle inherited the CC, CG and GG genotypes at domain L marker. These were reliable when verified by nucleotide sequence analysis of PCR products. The animals were genotyped and determined for tenderness phenotype with this marker that predicted variation of an intronic polymorphism at domain L of the calpastatin gene. Therefore, the ARMS method was simple, efficient technique, and suitable for detecting SNP at domain L marker of the calpastatin gene.
