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Reactive oxygen species (ROS) are important factors mediating aging according to the free radical theory of aging. Few studies have systematically measured ROS levels in relationship to aging, partly due to the lack of tools for detection of specific ROS in live animals. By using the H₂O₂-specific fluorescence probe Peroxy Orange 1, we assayed the H₂O₂ levels of live Caenorhabditis elegans with 41 aging-related genes being individually knocked down by RNAi. Knockdown of 14 genes extends the lifespan but increases H₂O₂ level or shortens the lifespan but decreases H₂O₂ level, contradicting the free radical theory of aging. Strikingly, a significant inverse correlation between lifespan and the normalized standard deviation of H₂O₂ levels was observed (p < 0.0001). Such inverse correlation was also observed in worms cultured under heat shock conditions. An oxidative fluctuation hypothesis of aging is thus proposed and suggests that the ability of animals to homeostatically maintain the ROS levels within a narrow range is more important for lifespan extension than just minimizing the ROS levels though the latter still being crucial.

Piezocatalysis, governed by piezo‐potential within piezoelectrics, has gained prominence for reactive oxygen species (ROS) generation, which is significant to environmental and biological applications. However, designing piezocatalysts with excellent piezocatalytic performance in a wide temperature and efficient charge carrier separation ability is still challenging. Herein, eco‐friendly BaTiO3 (BT)‐based perovskite ferroelectrics with tailored multiphase coexistence in a wide temperature range are constructed to boost higher piezoelectricity and large piezo‐potential, which is attributed to decreased polarization anisotropy by flat Gibbs energy profile. Elevated piezo‐potential in designed BT‐based piezocatalyst guarantees high‐efficient generation rate of •OH (200 µmol g−1 h−1) and •O2− (40 µmol g−1 h−1) by ultrasound stimulation, which is 3.5 times more than that of pure BT. Besides, piezocatalytic capacity to degrade dye wastewater shows a rate constant of 0.0182 min−1 and gives an antibacterial rate of 95% within 30 min for eliminating E. coli. Theoretical simulations validate that the local distortion of TiO6 octahedra also contributes to piezocatalytic performance by inducing electron–hole pairs separation in real space, and better response to slight structural deformation. This work is important to design high‐performance piezocatalysts with high‐efficiency ROS generation for sewage treatment and sonodynamic therapy. [ABSTRACT FROM AUTHOR]