  The crossover region in the phase diagram of polymer solutions, in the regime
above the overlap concentration, is explored by Brownian Dynamics simulations,
to map out the universal crossover scaling functions for the gyration radius
and the single-chain diffusion constant. Scaling considerations, our simulation
results, and recently reported data on the polymer contribution to the
viscosity obtained from rheological measurements on DNA systems, support the
assumption that there are simple relations between these functions, such that
they can be inferred from one another.
