Random examples of the probability distribution of orientations of XBs of cardiac myofibrils of rigor transgenic (Tg)-WT and MUT ventricles. Gray line is the best fit to a 3-parameter Gaussian. Graphs on the bottom show regular residuals of the counts. Left: WT muscle, FWHM = 0.469, AR2 = 0.932, mean intensity = 4.7 photons/ms, mean polarization = −0.269. Right: mutated muscle, FWHM = 0.563, AR2 = 0.942, mean intensity = 6.817 photons/ms, mean polarization = −0.223.