Guang, Qiang2022-11-010002-9939http://hdl.handle.net/1885/277339Inspired by the work of Spruck and Xiao on mean convex translators, in this note, we show that any closed and mean convex λ-surface in R with λ ≤ 0 must be convex. We also give a curvature estimate for mean convex λ-surfaces in R 3 3application/pdfen-AU© 2021 American Mathematical Society202110.1090/proc/152972021-11-28