In the 19th century, circulating libraries were essential for readers who could not afford to buy books.

In the 18th century, many novels first reached readers through a circulating library in the town square.

Scientists study the Hadley circulation to understand how heat and moisture are transported between the equator and the subtropics.

In comparative anatomy, researchers compared the efficiency of systemic circulations across different mammalian species.

Researchers compared the pulmonary circulations of several mammalian species to understand adaptations to high-altitude environments.

After the arterial blockage, collateral circulations developed around the affected area, maintaining tissue perfusion.