A geometry problem over a century old has just found its definitive answer. Mathematicians have confirmed that the solution ...

The shapes of these cells are puzzling. They have wavy edges and protrusions that fit together a bit like puzzle pieces. But what is it for? New research looking at the lymph capillary cells ...

She was very frustrated. She had been working on this jigsaw puzzle for a long time, and she was exhausted.  Clinching her fist tightly, with an odd-shaped piece in her grip, she gave in to all the ...