RF: defaults min kurtosis is always set to -3./7
RF: defaults min kurtosis is always set to -3./7

According to Barmpoutis and Zhuo (2011) this is the theoretical limit for regions of water confined to spherical pores (see full ref in code)

nilgoyyou/dipy,FrancoisRheaultUS/dipy,FrancoisRheaultUS/dipy,nilgoyyou/dipy