[R] ggplot2: sub/super-script axes labels

How are sub/superscripts designated for text in axis labels? As in this y-axis label: scale_y_continuous("Respiration, pmol O2 h-1") where the "2" needs to be subscripted and the "-1" needs to be superscripted. Thanks. Adam --- Adam

[R] ggplot2: edge outlines on points

The graphic design elements in ggplot2 are so well done for color graphics. Thank you! For BW publication graphs, there are a few options I would like to be able to tweak, but can't seem to find the grob handles necessary OR the right plotting strategy. Here's one problem I've been puzzling