Funding for this research was provided by:
BrightFocus Foundation (A2016241F)
National Institute on Aging (5P50AG005131)
U.S. Department of Veterans Affairs (5I01CX000565)
Received: 4 April 2017
Accepted: 27 June 2017
First Online: 2 August 2017
Ethics approval and consent to participate
: This study was carried out in accordance with the recommendations of University of California, San Diego (UCSD) Human Research Protections Program Board with written informed consent from all subjects. All subjects gave written informed consent in accordance with the Declaration of Helsinki. The protocol was approved by the UCSD Human Research Protections Program Board, study number 080012.
: Not applicable.
: The authors declare that they have no competing interests.
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