Implementation of the Mainen et al. pyramidal cell model from: Mainen ZF, Joerges J, Huguenard JR, Sejnowski TJ (1995) A model of spike initiation in neocortical pyramidal neurons. Neuron 15:1427-39.
See http://www.opensourcebrain.org/projects/mainenetalpyramidalcell for more details.