+<<fig=TRUE,echo=FALSE,results=hide,width=7,height=7>>=
+x <- seq(-1,0,length.out=20)
+y <- seq(-1,0,length.out=20)
+grid <- expand.grid(x=x,y=y)
+grid$z <- as.vector(to.kcal(60^(-outer(x,y))))
+print(wireframe(z~x*y,grid,cuts=50,
+ drape=TRUE,
+ scales=list(arrows=FALSE),
+ xlab=list("Average Vesicle Charge",rot=30),
+ ylab=list("Component Charge",rot=-35),
+ zlab=list("Charge Forward (k cal)",rot=93)))
+rm(x,y,grid)
+@
+
+