It's not available in sufficient quantity.

So many Americans accept “zero population growth” as a new canon of conventional wisdom that it comes as a surprise to hear the notion disputed.

To understand this name, note that the helicity is, roughly speaking, the spin in the direction of motion.

I thought I would like to learn about the dope scene anyway, and the boy must have some character, you know, if he got the monkey off his back (as they used to say in our time) without outside help.