Two mathematicians have proved that a straightforward question — how hard is it to untie a knot? — has a complicated answer.

The measurement system was tested last year and snow and fog were found to be issues. Chain gangs will remain a backup for such situations.

William Truswell, MD, FACS, operates his own cosmetic and reconstructive facial surgery practice. Dr. Truswell was the first in his area in Western Massachusetts to have an accredited private office ...