%%%%%%%%%%%%%REDEFINICION ITEMIZE%%%%%%%%%
\renewcommand{\labelitemi}{$\bullet$}%enumera con punto negro
\renewcommand{\labelitemii}{$\circ$}%enumera con circulo 
\renewcommand{\labelitemiii}{$\ast$}%enumera con asterisco
\renewcommand{\labelitemiv}{$\star$}%enumera con estrella
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%