I use the iopart class to write a paper. I include the table of contents with the usual command, but I got the part related with the appendices which overlap with the title (see figure).

How can I fixed this?
NB you will NEED the iopart class to compile.
A minimal working example - sorry some packages are unnecessary.
\documentclass[12pt]{iopart}
\usepackage[dvips]{graphicx}
\usepackage[usenames,dvipsnames]{xcolor}
\usepackage[latin1]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{latexsym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsthm}
%\usepackage{amsmath} % Error with iopart class
\usepackage{color}
\usepackage{psfrag}
\usepackage{rotating}
\usepackage{pgf,pgfsys,pgffor}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\usepackage[caption=false]{subfig}
\usepackage{tikz}
\usepackage{hyperref}
\bibliographystyle{iopart-num}
\begin{document}
\title{Main title}% Force line breaks with \\
\begin{abstract}
bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla
bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla
\end{abstract}
\maketitle
\tableofcontents
bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla
\section{Title 1}
bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla \ref{AppendixA}
\section{Title 2}
bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla bla bla blabla \ref{AppendixB}
\appendix
\section{Title A}
\label{AppendixA}
\section{Title B}
\label{AppendixB}
\end{document}


iopartclass does not make provisions for appendixes in the TOC. It will need a major rewrite of the\section,\l@sectionor both. The best advice is not to use a table of contents for IOP articles. – Danie Els Jul 10 '14 at 07:35iopart.clsin line 501, find\def\thesection{Appendix \Alph{section}}and replace it by\def\thesection{\Alph{section}}. If this is a solution for you, I will try to patch that or you could rephrase your question in order to find someone who is able to do this. – LaRiFaRi Jul 10 '14 at 07:49