A polygon's or polyhedron's Euler characteristic is just the number of corners minus the number of edges plus the number of faces.

One patient, in walking through the street, may be quite appalled at the approach of a runaway horse. The degree of appalment in another may be quite trifling.

semisupervised learning

The aerophore consisted of two main components — an air-filled canister about the size and shape of a lawn mower engine, which the diver wore on his back, and a new creation, a regulator, which automatically adjusted the pressure of the air in the tank to that of the water surrounding it.