diff -r e4050732ba15 -r f4112721a4b9 Slides/document/root.tex
--- a/Slides/document/root.tex	Tue Jan 24 16:51:01 2012 +0000
+++ b/Slides/document/root.tex	Tue Jan 24 17:43:07 2012 +0000
@@ -63,7 +63,8 @@
 \renewcommand{\isasymdots}{\isamath{...}}
 \renewcommand{\isasymbullet}{\act}
 \renewcommand{\isasymequiv}{$\dn$}
-
+\renewcommand{\isasymtau}{}
+\renewcommand{\isasymrightarrow}{$\Rightarrow$}
 % mathpatir
 %%\mprset{sep=1em}