a renormalization of the nuclear moment of inertia [@minkov06], has been used to describe the lowest quadrupole and octupole bands of the $N=90$ isotones $^{150}$Nd, $^{152}$Sm, $^{154}$Gd and $^{156}$Dy. A discussion of the octupole bands of $^{150}$Nd and $^{152}$Sm is also contained in the Ref.s [@bizzetirila; @bizzetipredeal]. Finally, an extension of the Extended Coherent State model [@raduta03] has been developed by A.A. Raduta and coworkers [@raduta06b; @raduta06c; @radutapredeal], to include in the model space also the lowest $K^\pi=1^+$ and $1^-$ bands, and the model predictions have been compared with the experimental data for several nuclei of the regions of the actinides and of the rare-earths.

\[S:2\]Phase transitions in the R – T region
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We summarize here the existing evidence for the evolution of nuclear shapes for Radium and Thorium isotopes in the transitional region $N=130 - 140$.

The Fig. \[F:1\], taken from I, shows the behavior of some indicators of quadrupole and octupole collectivity, as a function of the neutron number $N$, in the isotopic chain of Ra and Th. It has been noted in I that $^{226}$Th appears to be close to the critical point in the octupole deformation, while it possesses a stable quadrupole deformation $\beta_2$. At 