From Pritchard and Kell (2002) Eur. J. Biochem. 269, 3894-3904 which was

modified from Teusink et al. (2000) Eur J Biochem 267, 5313-5329.

This version uses the Vmaxes found by the best fit (R1) of Table 1 of the

Pritchard and Kell paper, and simulates a decrease of external glucose concentration from 100 to 2 mM.

(More model files at http://users.aber.ac.uk/lep/models.shtml)