Funding for this research was provided by:
Doris Duke Charitable Foundation (R01NS095793)
National Institute on Aging (P30AG10124, R21NS097749, P01AG017586)
Received: 28 August 2017
Accepted: 28 August 2017
First Online: 6 September 2017
Ethics approval and consent to participate
: Informed consent was obtained from next of kin in accordance with institutional review board guidelines of the University of Pennsylvania.
: The authors declare that they have no competing interests.
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