Funding for this research was provided by:
National Science Foundation (ANT-0944254)
Viet Nam National Foundation for Science and Technology Development (DFG 106-NN.06-2016.78)
Graduate University of Science and Technology, VAST (GUST.STS.ĐT2017-KHB01)
Article History
Received: 20 October 2017
Revised: 12 January 2018
Accepted: 16 January 2018
First Online: 31 January 2018
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: This manuscript does not contain any studies with human participants or animals performed by any of the authors.
: It was obtained from all individual participants included in the study.