© Sun et al.; licensee Springer. 2013
Received: 23 September 2013
Accepted: 23 September 2013
Published: 16 October 2013
A retraction article was published for this article. It is available from the following link; http://www.comcjournal.com/content/1/1/4.
This article is retracted.
One of the original authors of this article , Prof. Rod King, was unknowingly removed from the author list, and his significant contributions to the article as an author were not acknowledged.
The lead author accepts full responsibility and would like to apologize to Prof. King, as well as the co-authors of this article, the Editors and readers.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.