function xdot=glutfun(t,x,flag,Gin,Gout)
x1=x(1,1);
x2=x(2,1);
x3=x(3,1);

k12=2.4;k43=2.4;k21=42;k34=42;k14=1000;k41=1000;k23=1000;k32=1000;

xdot(1,1)=-k12*Gout*x1+k21*x2+k41*(1-x1-x2-x3)-k14*x1;
xdot(2,1)=k12*Gout*x1-k21*x2-k23*x2+k32*x3;
xdot(3,1)=k23*x2-k32*x3-k34*x3+k43*Gin*(1-x1-x2-x3);