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).

Scientists have uncovered a new explanation for how swimming bacteria change direction, providing fresh insight into one of ...

About half of all spiral galaxies appear to be rotating clockwise and the other half counterclockwise. The direction a galaxy rotates depends on your perspective. As an analogy, consider a spinning ...

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