How to remove my theme creator's name in header?

Hello,
I'm using Admin Treaks plugin to hide some part of the admin side of my site... but I can't remove the name of the company that create the theme I'm using (neuropro). I went in theme options, I couldn't find the way to remove it too.
Any suggestion? Ideas?

Thank you kindly for your answers

Regards,
PS: My site is http://www.positifstyle.com