Looking at the plots in Fig. , one can clearly see the different coupling patterns for different secondary structure elements. For the polyalanine α-helix, the nearest-neighbor couplings are generally larger than the second-neighbor couplings, while for the polyalanine and 1GPB 3 10 -helices, this pattern is reversed. For the polyalanine β-strand, the polyalanine β-hairpin, and Trpzip2, the second neighbor couplings are significantly smaller than for the helices.