Normally the sinoatrial node generates regular electrical pulses that spread across the chambers of the heart , causing the cells to contract in synchrony .
正常情况下，窦房结产生规律的电脉冲，传入各心房，再带动细胞同步收缩。
Brain scans show synchrony between the brains of mother and child ; but what they can 't show is the internal bond that belongs to neither alone a fusion in which the self feels so permeable it doesn 't matter whose body is whose .
When one fruit starts to ripen , it releases this hormone which is called ethylene , which is sensed by neighboring fruits , until entire trees and groves ripen more or less in synchrony .
