Couldn't generate code for the following reason:
Encountered unsupported operator partialdiff; 
  In MathML apply element.
  In MathML math element.
  In CellMLComponent element with cmeta:id TCa with name TCa.
  In Model element with cmeta:id seemann_sachse_weib_dossel_2003_version01 with name seemann_sachse_weib_dossel_2003_version01.