Funding for this research was provided by:
U.S. Department of Veterans Affairs (1I01RX000996-01, I21RX002069)
National Institutes of Health (P50 AG005138)
Uniformed Services University of the Health Sciences (601152N.0000.000.A1308)
Received: 5 September 2017
Accepted: 17 October 2017
First Online: 10 November 2017
: The authors declare that they have no competing interests.
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