Dr. Yao received his PhD in Environmental Science in 2006 from Rutgers University, and performed postdoctoral studies at Yale University afterwards. Dr. Yao joined Peking University via “100 Scholar Program” in 2007. Dr. Yao is currently a FULL Professor with Tenure in the College of Environmental Sciences and Engineering, Peking University, China. In 2018, Dr. Yao was appointed as Boya Distinguished Professor. Dr. Yao’s research interests are mainly focused on bioaerosols (airborne bacteria, virus, fungi and etc.). As of now, Dr. Yao has published 73 peer-reviewed journal articles, including 68 first/corresponding ones, and filed/received 16 national invention patents. Over the past 10 years, Dr. Yao along with his students have developed three major aerosol systems: GREATpa, SLEPTor and dLABer. These innovative systems have enabled his team to real-time monitor biological agents in the air, to study the PM2.5 health effects mechanisms on a single living cell level, and also to characterize the PM2.5 health effects on an animal level through real-time detecting breath-borne biomarkers. His studies were featured as research highlights by American Association for the Advancement of Science (AAAS), and ACS Chemical & Engineering News. One of his studies was published as an ES&T cover and won the Best ES&T Science Paper Award of 2018. His work has been recognized by three major aerosol awards, including the Marian Smoluchowski Award in 2013 from GAeF, the 2013 Asian Young Aerosol Scientist Award from Asian Aerosol Research Assembly (AARA), and also the Kenneth T. Whitby Award in 2014 from AAAR. His several research patents have been successfully commercialized and widely used in China. In 2015, Dr. Yao won a Second Prize for “P.R. China State Technological Invention Award”, and the 44th Geneva International Exhibition Special Gold Award in 2016. In 2017, Dr. Yao was awarded the NSFC Distinguished Young Scholar Award-one of the highest honor bestowed to a scientist below 45 years old in China, and in the same year Dr. Yao organized the first state level bioaerosol Xiangshan Conference. Dr. Yao serves an editorial board member/Guest Editor for J Aerosol Sci and Atmos Environ, and was an Awards Committee member of the American Association for Aerosol Research (AAAR). Currently, Dr. Yao is also serving as the Vice Chair for Indoor Environment and Health Branch, Chinese Society for Environmental Sciences. Involved in aim 1.