If the students activate the YASARA sequence bar on the bottom, they see that YASARA
includes the residues 19-27 in the helix. I think, though, that Glu-28 belongs to
the helix. The assistants can discuss with the students that the ends of helices
are a matter of definition. How far can the C-α be away from the helix axis?
Should both the N and the C=O point in the right direction? How good should the
last hydrogenbond be? Etcetera.