Helix	j and j + 1 and j + 2 ∈ H	→	j + 1 = helix
Strand	j and j + 1 and j + 2 ∈ S	→	j + 1 = strand
Type I turn	j + 1 ∈ T and j + 2 ∈ T	→	j + 1 = Type I turn (residue i + 1)
	j ∈ T and j + 1 ∈ T	→	j + 1 = Type I turn (residue i + 2)
Type I′ turn	j + 1 ∈ T′ and j + 2 ∈ T′	→	j + 1 = Type I′ turn (residue i + 1)
	j ∈ T′ and j + 1 ∈ T′	→	j + 1 = Type I′ turn (residue i + 2)
Type II turn	j + 1 ∈ U and j + 2 ∈ T′	→	j + 1 = Type II turn (residue i + 1)
	j ∈ U and j + 1 ∈ T′	→	j + 1 = Type II turn (residue i + 2)
Type II′ turn	j + 1 ∈ U′ and j + 2 ∈ T	→	j + 1 = Type II′ turn (residue i + 1)
	j ∈ U′ and j + 1 ∈ T	→	j + 1 = Type II′ turn (residue i + 2)
Coil	None of the above	→	j + 1 = Coil