Figure 6.
A schematic of the writhe calculation for a nucleosome in a regular fibre. Scales and length have been arbitrarily chosen for the sake of clarity. The curve represents the tangent indicatrix of DNA in the fibre. Point Ti represents the vertex of the ith linker tangent vector. The circular part corresponds to the indicatrix of the DNA wrapping around the nucleosome. The central point is the direction of the fibre axis. The surface 𝒮(α, β) of equation (5.4) corresponds to the spherical triangle FTiTi+1.