  In universal extra-dimensional models a conserved $Z_2$ parity ensures the
stability of the lightest Kaluza-Klein particle, a potential dark-matter
candidate. We show here that boundary-localized kinetic terms, in general, do
not preserve this symmetry. We examine the single production of a Kaluza-Klein
excitation of the photon and its decay to zero-mode fermion-antifermion pairs
in the presence of such terms. We explore how experiments at the Large Hadron
Collider at CERN can help constrain the boundary-localized kinetic terms for
different choices of the compactification radius.
