The Editor-in-Chief has retracted this article (Taşkin et al. 2015) because it contains substantial overlap with previously published articles (Uygun et al. 2013; Chang 2014). Specifically, Figures 2, 3, 4, 5 and 6 as well as Tables 1, 2, 9, 10 and 13 have been published previously in Uygun et al. (2013).

None of the authors responded to any correspondence from the publisher about this retraction.