Yifan Ying

1 Introduction Sarcopenia, a geriatric syndrome marked by the gradual decline in both skeletal muscle mass and function, represents a significant health concern, particularly among aging populations (Rosenberg 1997). As a multifaceted condition, sarcopenia not only contributes to diminished physical performance but also poses a substantial risk for adverse health outcomes, including falls, fractures, and a decline in overall quality of life (Cruz-Jentoft and Sayer 2019).

On-chip gas reaction nanolab for in situ TEM observation† The catalysis reaction mechanism at nano/atomic scale attracted intense attention in the past decades. However, most in situ characterization technologies can only reflect the average information of catalysts, which leads to the inability to characterize the dynamic changes of single nanostructures or active sites under operando conditions, and many micro–nanoscale reaction mechanisms are still unknown.