Funding for this research was provided by:
National Institute on Drug Abuse (R01DA038675)
National Institute on Alcohol Abuse and Alcoholism (R24AA022919)
National Institute of Mental Health (MH58107)
UCLA Center for AIDS Research (5P30AI028697)
National Center for Advancing Translational Sciences (UL1TR000124)
William T. Grant Foundation (180039)
National Research Foundation, South Africa (N/A - no reference number available)
Received: 15 February 2018
Accepted: 10 July 2018
First Online: 3 August 2018
Ethics approval and consent to participate
: The study has been approved by the Institutional Review Boards (IRB) of the University of California, Los Angeles (IRB 14–001587) and Stellenbosch University (N14/08/116). Informed consent will be obtained from all participants prior to participation in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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