In a “normal” electrocardiogram (ECG), the transition of the QRS axis in the precordial leads occurs between leads V 3 and V 4 (i.e., there is a dominant S in V 3 and a dominant R in V 4).

Researchers have unseated a previous theory for the mechanism underlying bacterial flagella movement, changing our ...

Usually, tornadoes in the U.S. rotate counterclockwise. Coriolis force, imparted due to the Earth’s rotation, causes air around low centers to circulate counterclockwise in the northern hemisphere.