Funding for this research was provided by:
Defense Intelligence Agency (HHM402-14-1-007)
Received: 26 April 2018
Accepted: 11 July 2018
First Online: 27 July 2018
Ethics approval and consent to participate
: Not applicable. We did not seek approval from an ethics board/institutional review board because the data were from publically available sources.
: Not applicable
: The authors declare that they have no competing interests.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
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