  We study extreme-ultraviolet emission line spectra derived from
three-dimensional magnetohydrodynamic models of structures in the corona. In
order to investigate the effects of increased magnetic activity at photospheric
levels in a numerical experiment, a much higher magnetic flux density is
applied at photospheric levels as compared to the Sun. Thus, we can expect our
results to highlight the differences between the Sun and more active, but still
solar-like stars. We discuss signatures seen in extreme-ultraviolet emission
lines synthesized from these models and compare them to signatures found in the
spatial distribution and temporal evolution of Doppler shifts in lines formed
in the transition region and corona. This is of major interest to test the
quality of the underlying magnetohydrodynamic model to heat the corona, i.e.
currents in the corona driven by photospheric motions (flux braiding).
