1 Erratum to: Acta Biotheor (2012) 60:333–356 DOI 10.1007/s10441-012-9161-5

The symbolic expression in the second paragraph of Sect. 3 has been published incorrectly. The correct expression is as follows:

$$ {{\left( {1 - \frac{\gamma N}{\alpha }} \right)} \mathord{\left/ {\vphantom {{\left( {1 - \frac{\gamma N}{\alpha }} \right)} m}} \right. \kern-0pt} m} $$