Fig. 2.

Validating VMV near a glass boundary and linearity of our culture media. (A) A 4.5 µm vaterite microsphere rotating at 6.4 Hz in water at room temperature near a solid boundary comprising a glass wall. The gap thickness is measured as shown. Scale bar is 10 µm (B) Experimental data and fit of relative rotation rates as a function of gap thickness. The residual of fit is 0.0791, mostly due the point closest to the boundary. Note the fine scale on the vertical axis. (C) PMR measurement in EGL collapsing media. (D) PMR measurement in EGL preserving media. PMR confirms linearity of the culture media across observed frequencies.