  We investigate dynamic nuclear polarization in quantum point contacts (QPCs)
in the integer and fractional quantum Hall regimes. Following the application
of a dc bias, fractional plateaus in the QPC shift symmetrically about half
filling of the lowest Landau level, \nu=1/2, suggesting an interpretation in
terms of composite fermions. Polarizing and detecting at different filling
factors indicates that Zeeman energy is reduced by the induced nuclear
polarization. Mapping effects from integer to fractional regimes extends the
composite fermion picture to include hyperfine coupling.
