Phys. Rev. Focus--11 FEB 2005 PHYSICAL REVIEW FOCUS   11 February 2005   http://focus.aps.org/ David Ehrenstein and Davide Castelvecchi, American Physical Society Introductions to the Focus stories of the past week; visit http://focus.aps.org for the complete stories. WATCHING ATOMS MOVE Researchers usually compare "before" and "after" pictures of  typical regions of a material to see how it changes during a phase  transition. But now a team has watched a specific set of atoms  continuously during a surface phase transition to see exactly how  it occurs, and has made atomic-scale movies. In the 4 February PRL  they describe their ultrastable scanning-tunneling microscope, or  STM, that can remain fixed on the same set of surface atoms, even  as the temperature rises by 100 Kelvin--a huge warming that would  cause other microscopes to "lose their place." By studying one  especially pristine region of the surface, the researchers were  able to learn how the transition occurs, atom-by-atom, in a  perfectly clean system. (I. Brihuega et al., Phys. Rev. Lett. 94, 046101) Link to the paper: http://link.aps.org/abstract/PRL/v94/e046101 COMPLETE Focus story and PHASE TRANSITION VIDEOS at  http://focus.aps.org/story/v15/st6 NEW FOCUS POSTER: Go to http://focus.aps.org/poster.html to download the  new poster. For free copies on glossy paper, follow the email ordering  instructions on the page. Also from PRL (stories from AIP's Physics News Update): MEMORY AND CRITICAL AVALANCHES IN THE BRAIN Story at http://www.aip.org/pnu/2005/split/719-1.html (Clayton Haldeman and John M. Beggs, Phys. Rev. Lett. 94, 058101) LIQUID CARBON CHEMISTRY Story at http://www.aip.org/pnu/2005/split/719-2.html (S. L. Johnson et al., Phys. Rev. Lett. 94, 057407) --- Copyright 2005, The American Physical Society. You are currently subscribed to focus as:  To unsubscribe, send blank e-mail to:  To subscribe, send blank e-mail to:  The Focus list web interface is at: http://lists.apsmsgs.org/read/focus.html APS MEMBERS, READ THIS APS Member Number: [PR090950] If there is a number in the brackets, then your Focus e-mail address is "synchronized" with your APS membership address, and you should make any future changes at http://www.aps.org/memb/services.html. For more information, send a blank e-mail to .