aDepartment of Biology, Portland State University, Portland, Oregon, USA
bDepartment of Environmental Health Sciences, School of Public Health, UCLA, Los Angeles, California, USA.
cDepartment of Biology, University of Nebraska-Kearney, Kearney, Nebraska, USA.
dDepartment of Biology, San Francisco State University, San Francisco, California, USA.
Copyright ©2012, Korea Centers for Disease Control and Prevention
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