IZIUM, Ukraine — It's not the sight of 19th century buildings pockmarked by shell fragments and bullets that shocks visitors most in this eastern Ukrainian town. It's the fact that they drive into the ...

In the olden days — a mere 20 years ago — people talked about hard colloidal particles and soft vesicles or micelles, which covered all sizes from the micrometre to the nanometre regime. Now we talk ...