But it would make sense to promote the economic benefits of a modernized and streamlined immigration system that would allow the regulated flow of tourists and workers from Latin America.

CNN: Obama pays attention to Latin America

The commission has long run the St Lawrence hydro-power project at Cornwall, Ontario, and regulated the river flow without dispute or political interference.

ECONOMIST: Environmental management faces moving targets

Growers and distributors have invested in "ripe rooms, " where temperature, humidity and air flow are all regulated.

WSJ: Avocado Sales Are Rising, as Consumers Buy Into the Fruit as a Source of 'Healthy Fats'

As the flow of water can be regulated, it's also not affected by seasonal or daily changes in weather or water patterns.

FORBES: Getting Power From Salty Water

Power stations are built on rivers with a consistent and steady flow, either natural or regulated by a reservoir at the head of the facility.

FORBES: Hydroelectric Revolution: A River Runs Through It

Sniffing is regulated by the soft palate, a flap of tissue in the back of the throat that directs the flow of air through the mouth and nose.

ECONOMIST: Monitor

But the Asian crisis, like the 1995 Mexican crisis before it, has shown that some types of capital can flow out even more quickly than they flowed in, causing serious economic harm in countries with badly regulated financial systems.

ECONOMIST: Can capital controls stop poor countries crashing?