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Table 3 Summary of physical parameters obtained from the fit of Boettiger’s data [2] for active (A), inactive (I) and repressed (R) epigenetic domains through the Bayesian procedure (mean values, see Additional file 1: Figs. S3–S5)

From: Polymer coil–globule phase transition is a universal folding principle of Drosophila epigenetic domains

State Active Inactive Repressed
  Bayesian fit Estimate Bayesian fit Bayesian fit
Fitted:     
\(\varepsilon \, [k_BT]\) \(0.1 \pm 0.05\)   \(0.32 \pm 0.03\) \(0.44 \pm 0.04\)
\(K_{\mathrm {bp}}\) [bp] \(K_{\mathrm {nm}} \propto K_{\mathrm {bp}}^{0.56}\) ~ 1100–1500 \(3900 \pm 1300\) \(1500 \pm 550\)
\(K_{\mathrm {nm}}\) [nm] ~ 32–37 \(60 \pm 9\) \(37\pm 6\)
\(a_0\) [nm] \(130 \pm 7\)   \(93 \pm 10\) \(94 \pm 4\)
\(a_{\infty }\) [nm] \(290 \pm 15\)   \(170 \pm 10\) n/a
\(N_{0}\) \(630 \pm 370\)   \(10 \pm 6\) n/a
Derived:     
\(c = \frac{K_{\mathrm {bp}} }{K_{\mathrm {nm}}}\) [bp/nm]   ~ 35–40 \(66 \pm 24\) \(40 \pm 16\)
\(c_{10}\) [nucl./10 nm]   ~ 1.9–2.2 \(3.5 \pm 1.5\) \(2 \pm 1\)
C [\(\hbox {nucl.}/K_{\mathrm {nm}}\)]   ~ 6–8 \(20 \pm 7\) \(8 \pm 3\)
  1. Errors are calculated from the standard deviations of marginalized parameter distributions. At the bottom, some derived geometrical parameters as the compaction in bp/nm, in nucleosomes per 10 nm, the number of nucleosomes per Kuhn segment C. Derived parameters are calculated by assuming a nucleosome repeat length of 182 bp for active domains, 192 bp for inactive and repressed domains [25]. (The numerical results obtained with 182 or 192 bp are very close, in the error range). For active domains, the right column estimates are obtained by including architectural features, see “Discussion