AUTHOR=Ren Hao , Liang Junrui , Feng Jicheng , Zhang Xiaosheng TITLE=Editorial: Miniaturized Bioenergy and Energy Harvesting Systems JOURNAL=Frontiers in Mechanical Engineering VOLUME=7 YEAR=2021 URL=https://www.frontiersin.org/journals/mechanical-engineering/articles/10.3389/fmech.2021.741190 DOI=10.3389/fmech.2021.741190 ISSN=2297-3079