Plattner et al. Vol. 139, No. 7, December 1997. Pages 1709–1717.

Underlined portions of the text below represent corrected symbols that appeared in the derivation of equation 2 on p. 1711.

Assume that the centers of granules are distributed randomly and uniformly over the cell volume, except for those regions in which steric hindrance does not allow the presence of a granule larger than a certain diameter because of overlap with the cell boundary. Then the probability pρ(d) to find the center of a granule of radius ρ at a distance d from the boundary of a cell with radius r0 is given by

\begin{equation*}{\mathit{p}}_{{\rho}}({\mathit{d}})= \left\{ \begin{matrix}0\;\;\;\;\;\;\;for\;{\mathit{d}}<{\mathit{{\rho}}} \enskip & \\ const{\cdot}4{\pi}({\mathit{r}}_{0}-{\mathit{d}})^{2}\;for\;{\mathit{d}}>{\mathit{{\rho}}} \enskip & \end{matrix} \right \end{equation*}

where 4π(r0d)2dr is the volume of a shell of width dr at distance (r0d) from the center of the cell.