It does however follow an earlier association made between shift work and breast cancer.

BBC: 'Night shift link' to ovarian cancer

With the weaker yen, some question whether Nissan will follow through with its plan to shift SUV production to the U.S. On April 12, the Nikkei business daily reported that the auto maker may delay the production shift.

WSJ: Weaker Yen Is Mixed Bag for Japan Auto Makers

Consultants have told the BBC there are also concerns over staffing the emergency department, covering holiday and sick leave, and the fact that the rest of the hospital system does not follow a seven-day working pattern shift, which has a knock on effect especially at the weekends.

BBC: Northern Ireland

Other buildings will be completed soon, and though there aren't many now under construction to follow them, Gordon Brown's determination to shift civil-service jobs out of London will dampen demand in the years ahead.

ECONOMIST: London office rents

After all, they stand to benefit from a huge shift in what the Soviets used to call the strategic "correlation of forces" should America actually follow through with this sort of unilateral disarmament.

CENTERFORSECURITYPOLICY: Center For Security Policy