Funding for this research was provided by:
Ministry of Higher Education, Malaysia (LRGS/2015/UKM-UKM/NANOMITE/04/01, LRGS (2015)/NGOD/UM/KPT)
Text and Data Mining valid from 2018-02-20
Received: 11 September 2017
Accepted: 29 January 2018
First Online: 20 February 2018
: All authors declare that they have no competing interests.
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