Complex sentence: Bernstein's work was concentrated in the fields of neurobiology and biophysics, largely being recognized for his "membrane hypothesis" in regards to the origin of the "resting potential" and the "action potential" in the nerve.
Split into simpler sentences: Bernstein's work was concentrated in the fields of neurobiology and biophysics. He is largely recognized for his "membrane hypothesis" in regards to the origin of the "resting potential" and the "action potential" in the nerve.