  By considering non-orientable surfaces in the surgered manifolds, we show
that the 10/3- and -10/3-Dehn surgeries on the 2-bridge knot $9_{27} =
S(49,19)$ are not cosmetic, i.e., they give mutually non-homeomorphic
manifolds. The knot is unknown to have no cosmetic surgeries by previously
known results; in particular, by using the Casson invariant and the Heegaard
Floer homology.
