Before revision:  {\it  {\it   Fitting with a linear behavior \alpha(T), we find evidence  for a decreasing growth rate as a function of T . However, a decrease in the growth rate is visible also in the very low-T data.
After revision:  {\it {\it extended Fitting with a linear behavior \alpha(T), we find evidence for a decreasing growth rate as a function of T . However, a decrease in the growth rate is visible also in the very low-T data.