Abstract The typical spectrum of the prompt emission gamma-ray bursts (GRBs) indicates that electron cooling is suppressed in spite strong magnetic field standard synchrotron model. Recent particle-in-cell simulations show particle acceleration by reconnection a magnetically dominated plasma can lead to small pitch angles especially low-energy region. Such angle prevents electrons from via radi...

abstract introduction: the mineral content of dentin increases with age and its primary structure is altered. these changes may have unknown effects on efficiency of adhesive systems. the aim of this study was to find the effect of aging on dentin bonding agents. methods and materials: fourty eight extracted human premolars were divided into 2 groups under 15 years old & 2 groups over 45 years ...