So far no bill has bounced between the Houses more than 15 times, but one constraint on the process might be finding a different ink to signify the exchange of amendments.

BBC: That most mysterious of Westminster rituals

Like the movie business, the games business is limited by the bandwidth-constraint online, but it has more flexibility to get around the problem.

ECONOMIST: Games and the Internet go well together

The more intensely you feel those emotions, the bigger the constraint may be.

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Freedom from constraint by others (negative liberty) is more urgent or basic, he argued, than freedom to realise your potential (positive liberty).

ECONOMIST: Isaiah Berlin

This, to an extent, mitigates the supply constraint reason for the lower-than-expected sales but more people preferring to pre-order the device still remains a viable candidate.

FORBES: Overwhelming Pre-Order Demand Could Be The Reason Behind Apple's Disappointing iPhone 5 Sales

But we're also in an era of fiscal constraint, which means that we've got to start finding more creative, new approaches to financing these projects.

WHITEHOUSE: President Obama: ��Economy Back from the Brink��

The choice of electrolyte is a critical constraint that drives many of the choices fuel cell developers must make as they pursue more efficient fuel cell technologies.

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