Studies are under way to determine whether the devices can also prevent that condition or moderate the symptoms of heart failure.

Though those devices do not prevent plane crashes, they are invaluable for investigating them.

Eventually, telephone companies designed devices to prevent this misuse of the loop around.

A cast or similar device prevents the lower leg and ankle from moving.

A mechanical device prevents a train from moving if the doors are open.

These devices prevent an unchanging image from burning itself permanently into the screen.

And they amplify the original devices to prevent abuse of official power.

Power systems contain protective devices to prevent injury or damage during failures.

But the devices, known as specs, would, in the wild, prevent them from gathering food effectively, he said.

He needs devices to prevent that happening on the field.