  We study the Lagrangian dynamics of semi-flexible macromolecules in laminar
as well as in homogeneous and isotropic turbulent flows by means of
analytically solvable stochastic models and direct numerical simulations. The
statistics of the bending angle is qualitatively different in laminar and
turbulent flows and exhibits a strong dependence on the topology of the
velocity field. In particular, in two-dimensional turbulence, particles are
either found in a fully extended or in a fully folded configuration; in three
dimensions, the predominant configuration is the fully extended one.

Fluid Dynamics;Chaotic Dynamics