  In a recent Nature Materials article, Brown et al. reported a generality of
shear thickening in dense suspensions and demonstrated that shear thickening
can be masked by a yield stress and can be recovered when the yield stress is
decreased to below a threshold. However, the generality of the shear thickening
reported in the article may not be necessary true when a high electric/magnetic
field is applied on an ER/MR fluid. Shear thickening of ER fluid and MR fluid
under high electric/magnetic fields at low shear rates, indicating an obvious
phase change inside the dense suspensions has been observed.
