Second row: The first picture was taken by Jerry Lee at the Academia Sinica at the National Taiwan University in Dec., 2011. The second picture was taken by Andrea Li at the Chern Institute of Mathematics at Nankai University in Oct., 2011.
Third row: The picture on the left was taken by Nung-Sing Sze at the International Linear Society Conference at Shanghai, China, July, 2007. The picture in the center was taken by Ilya Spitkovsky at the Eighth WONRA - Workshop on Numerical Ranges and Numerical Radii, Bremen, Germany, 2006. The picture on the right was taken by Tin-Yau Tam at the Fourth WONRA -- Workshop on Numerical Ranges and Numerical Radii, Madison, Wisconsin, June, 1998.