The present work consists of dynamic detection of damages in reinforced concrete bridges by using a MMUM (mathematical model updating method) from incomplete test data. A well suited finite element model of a repair...The present work consists of dynamic detection of damages in reinforced concrete bridges by using a MMUM (mathematical model updating method) from incomplete test data. A well suited finite element model of a repaired bridge is carried out. The diagnosis enables us to locate and detect the damage in a reinforced concrete bridge. Thus, developments of analytical predictions have been checked by modal testing techniques. Besides, the FTCS (finite time centered space) scheme is developed to solve the set of equations which can easily handle finite element matrices of a bridge model. It is shown in this study that the method is applied to detect damages as well as existing cracks in real time of a repaired bridge. To check the efficiency of the method, the repaired bridge of OuedOumazer in Algeria has been selected. It is proven that identification methods have been able to detect the exact location of damage areas to be corrected avoiding the inaccuracy from the finite element model for the mass, stiffness and loading.展开更多
DNA double-strand break (DSB) is the most deleterious form of DNA damage and poses great threat to genome stability. Eu- karyotes have evolved complex mechanisms to repair DSBs through coordinated actions of protein...DNA double-strand break (DSB) is the most deleterious form of DNA damage and poses great threat to genome stability. Eu- karyotes have evolved complex mechanisms to repair DSBs through coordinated actions of protein sensors, transducers, and effectors. DSB-induced small RNAs (diRNAs) or Dicer/Drosha-dependent RNAs (DDRNAs) have been recently discovered in plants and vertebrates, adding an unsuspected RNA component into the DSB repair pathway. DiRNAs/DDRNAs control DNA damage response (DDR) activation by affecting DDR loci formation and cell cycle checkpoint enforcement and are required for efficient DSB repair. Here, we summarize the findings of diRNAs/DDRNAs and discuss the possible mechanisms through which they act to facilitate DSB repair.展开更多
文摘The present work consists of dynamic detection of damages in reinforced concrete bridges by using a MMUM (mathematical model updating method) from incomplete test data. A well suited finite element model of a repaired bridge is carried out. The diagnosis enables us to locate and detect the damage in a reinforced concrete bridge. Thus, developments of analytical predictions have been checked by modal testing techniques. Besides, the FTCS (finite time centered space) scheme is developed to solve the set of equations which can easily handle finite element matrices of a bridge model. It is shown in this study that the method is applied to detect damages as well as existing cracks in real time of a repaired bridge. To check the efficiency of the method, the repaired bridge of OuedOumazer in Algeria has been selected. It is proven that identification methods have been able to detect the exact location of damage areas to be corrected avoiding the inaccuracy from the finite element model for the mass, stiffness and loading.
基金supported in part by China National Funds for Distinguished Young Scientists(31225015)National Key Scientific Research Program of China(2012CB910900)to Qi YiJun
文摘DNA double-strand break (DSB) is the most deleterious form of DNA damage and poses great threat to genome stability. Eu- karyotes have evolved complex mechanisms to repair DSBs through coordinated actions of protein sensors, transducers, and effectors. DSB-induced small RNAs (diRNAs) or Dicer/Drosha-dependent RNAs (DDRNAs) have been recently discovered in plants and vertebrates, adding an unsuspected RNA component into the DSB repair pathway. DiRNAs/DDRNAs control DNA damage response (DDR) activation by affecting DDR loci formation and cell cycle checkpoint enforcement and are required for efficient DSB repair. Here, we summarize the findings of diRNAs/DDRNAs and discuss the possible mechanisms through which they act to facilitate DSB repair.