Before revision:  For these calculations{\bf   we use a model that captures both the mechano-chemistry of each individual ribosome as well as their steric interactions in ribosome traffic on the same mRNA track.
After revision:  For these calculations{\bf , 598 (2008)). The form of this distribution predicted by our theory is consistent with that extracted from the experimental data. For our quantitative calculations, we use a model that captures both the mechano-chemistry of each individual ribosome as well as their steric interactions in ribosome traffic on the same mRNA track.