function xdot=glucfun2(t,x);
%  Glucose-Dependent Insulin Secretion reduced model
%  example call:  ode45('glucfun2',[0:80],[6;.3]);

global Vm Km Vs Ks Vmax2 K2 Vmax1 K1 L ko Io Go KI Ki tau n m

Gis=x(1,1);
Jis=x(2,1);
G=Go;
Rm=(Vm*Gis)/(Km+Gis);
Rs=(Vs*(Rm^4+L^4))/(Ks^4+Rm^4+L^4);
I=Rs/ko;
Jinf=KI/(I+KI);
R1=(K1*Vmax1*(G-Gis)*I^n)/((K1+G)*(K1+Gis)*(Ki^n+I^n));
R2=(K2*Vmax2*(G*Jis^m-Gis))/((K2+G)*(K2+Gis));
xdot(1,1)=R1+R2-Rm;
xdot(2,1)=(Jinf-Jis)/tau;