We present a  joint work with Richard Bamler. We consider Ricci flows that satisfy scalar curvature bounds. It is found that the time derivative of the heat equation and the curvature tensor have better than expected bounds. Based on these, we address a number of problems which have been around for some time. Among these are: backward pseudolocality, $L^{^2}$-curvature bounds in dimension $4$, bounds on distance distortion at different times in low dimensions and Gaussian bounds for the heat kernel.