Alpha-1 antitrypsin dysfunction and large artery stroke.

American tree frog Hypsiboas punctatus, an amphibian that exhibits natural fluorescence. Carlos Taboada et al. traced the frog’s fluorescence to a class of compounds called hyloins, and found that in low-light conditions the fluorescence substantially enhances the brightness of individuals and matches the sensitivity of amphibian night vision. See the article by Taboada et al. on pages 3672–3677. Image courtesy of Julián Faivovich and Carlos Taboada. From the Cover