In tests on seven people with nocturnal asthma, 13 non-nocturnal asthmatics and 11 non-asthmatics, lung function tests revealed that patients with nocturnal asthma had the highest levels of melatonin and the greatest drop in lung function overnight.

BBC: NEWS | Health | Sleep supplement asthma warning

They are also unsure whether the early drop in brain function could lead to conditions such as dementia.

BBC: Smoking 'rots' brain, says King's College study

Researchers from the National Jewish Medical and Research Center in Denver, US, found that the hormone caused a drop in lung function in asthmatics.

BBC: NEWS | Health | Sleep supplement asthma warning

The suggestion from scientists was that the drop in lung function was linked at least in part to the high levels of melatonin in their system.

BBC: NEWS | Health | Sleep supplement asthma warning

PackBot offers unprecedented mobility and durability-it can be thrown into a building through a window, climb stairs, drop 20 feet and still function properly.

ENGADGET: Interview: Helen Greiner, Chairman and Cofounder of iRobot, Corp.

The drop in profitability appears to be a function not of the health insurance segment, which reported the same margin as last year, but of the smaller business that sells disability, property and other insurance.

FORBES: Cigna's Strong Earnings Should Be Sustainable

Once morningstar.com's premium fund selector spits out the funds from our screen, we drop them into fund tracker Morningstar's portfolio function.

FORBES: Magazine Article

More direct evidence from studies of experiments with animals and humans, however, suggests that we may have to alter the very concept of what we mean by hearing loss, and that current tests - particularly pure-tone audiometry which measures our ability to perform "pin-drop" hearing - may not be sufficient to pick up the early signs of a decline in hearing function.

BBC: Viewpoint: Does deafness contribute to dementia?