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Liu J, Hutchison K, Perrone-Bizzozero N, Morgan M, Sui J, Calhoun V.Liu J, et al.PLoS One. 2010 Oct 7;5(10):e13209. doi: 10.1371/journal.pone.0013209.PLoS One. 2010.PMID: 20949057Free PMC article.