Funding for this research was provided by:
National Institute on Drug Abuse (K23DA047473)
Received: 28 February 2020
Accepted: 14 May 2020
First Online: 12 June 2020
Ethics approval and consent to participate
: The study was approved by Stanford’s IRB (protocol # 48784) 3000 El-Camino Real, 5 Palo Alto Square, 4th Floor, Palo Alto, CA 94306, USA. An informed consent will be obtained from all participants in the study.
: Not applicable
: All authors declare that they have no competing interests.