<html><head></head><body><div class="ydpa67164fbyahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div><div dir="ltr" data-setdir="false"><div><div dir="ltr" data-setdir="false"> <div><div dir="ltr" style="font-family: Helvetica Neue, Helvetica, Arial, sans-serif; font-size: 16px;" data-setdir="false">I attended the online APS Division of Fluid Dynamics meeting at the beginning of the week. Sunday morning had a "Mini Symposium on Infectious Diseases." There was a very good presentation by Howard Stone of Princeton, showing saliva threads between lips and the vocal chords breaking up into droplets and much more. He also showed visualizations of buoyancy effects in leakage around masks. Martin Bazant of MIT presented an analysis of building safety which seems very practical and is available on his web site with a spread sheet. His APS talk and a paper that is under review, "<span>Beyond Six Feet: A Guideline to Limit Indoor Airborne Transmission of COVID-19, " M. Z. Bazan and J. W. M. Bush</span> also are available. </div></div></div><div dir="ltr"><br clear="none"></div><div dir="ltr"><a href="http://web.mit.edu/bazant/www/COVID-19/" rel="nofollow" target="_blank" fg_scanned="1" class="">http://web.mit.edu/bazant/www/COVID-19/</a> <br clear="none"></div><div><br></div><div dir="ltr" data-setdir="false">Frank</div><div><br></div><div><br clear="none" style="color: rgb(38, 40, 42); font-family: Helvetica Neue, Helvetica, Arial, sans-serif; font-size: 16px;"></div></div> </div><div><br></div><div class="ydpa67164fbsignature"><div style="font-family:Helvetica, Arial, sans-serif;font-size:16px;"><div>Frank W. Chambers</div><div>2 Sabroso Pl.</div><div>Santa Fe, NM 87508</div><div>Home: (505) 466-1942</div><div>Cell: (405) 614-4353</div></div></div></div></div></body></html>