The deformed cells block blood vessels and cut off the flow of oxygen to tissue in the body.
VOA: special.2009.12.16
Initially, the projected revenue for Scotland - and hence the cut in block grant - would be calculated by the Treasury with an initial guarantee of financial stability.
It suggests that London set Scottish rates at 10p less than those for Britain as a whole, and cut its block grant by the amount that the difference in rates might be expected to raise.
Central to the Scotland Bill is a recommendation that Scotland should take charge of half the standard income tax rate - 10p - with a corresponding cut in the block grant Scotland gets from the Treasury.