The chiral version of the QMC model, in which the effect of gluon and pion
exchanges is included self-consistently, is applied to the hyperons in a
nuclear medium. The hyperfine interaction due to the gluon exchange plays an
important role in the in-medium baryon spectra, while the pion-cloud effect is
relatively small. At the quark mean-field level, the Ξ feels more
attractive force than the \Sigma or \Xi in matter.Comment: 9 pages, 6 figure