PDE and ODE implementation

Dear all,

I am quite new in COMSOL world and I would like to ask some help for my problem.

I am trying to implement the model described in the paper which I attached here, and I would know if someone can help me with it or can suggest some good tutorial to implement PDE and ODE equation.
I tried to read the Users Guide, but I am not still able to figure out my problem.

I would be grateful if someone could help me.
Regards,
R