This article [J. Biomed. Opt. 16, 046022 (2011)] was originally published on 29 Apr. 2011 with an error in the author affiliations. A footnote has been added to indicate that the author Abdollah Hassanzadeh is currently affiliated with the University of Kurdistan, Department of Physics, Sanandej, Kurdistan, Iran.
The article was corrected online on 6 May 2011. The article appears correctly in print.