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We present results from two-dimensional numerical simulations of a supersonic turbulent flow with parameters characteristic of the interstellar medium at the 1 kpc scale in the plane of the galactic disk, incorporating threshold star formation (SF), self-gravity, rotation and magnetic fields. We find that rotation tends to inhibit SF but does not completely eliminate it. Concerning the magnetic field: a) the evolution of the simulations depends in a complex manner on the field's intensity, topology and scale. b) It is found that a seed uniform magnetic field is necessary for the maintenance of magnetic energy, suggesting that the latter is stored in large-scale Alfv\'en waves. c) The uniform, large-scale component of the field inhibits the expansion of ``HII'' regions as well as the production of strong turbulence-induced compressions. d) The turbulent component of the field promotes SF. e) An inverse (from small to large scales) turbulent magnetic cascade is observed. f) The large-scale azymuthal field appears to be originated by the large-scale Galactic shear. Concerning the cloud energetics, an earlier conjecture that there is no tendency to form virialized clouds, but that nearly-virial clouds have the longest lifetimes and are thus overabundant is again supported by the simulations.
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