Without the safety valves of emigration to Europe, which is getting harder, and families' willingness to support those out of work, Morocco would look far less stable.

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The college spread has elevated the function of slot receivers, who often work the middle of the field as safety valves whom the quarterback can target if pressured.

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The Renewable Fuels Standard builds in "safety valves" in the event of extreme economic harm in states or regions or if the ethanol industry does not produce an adequate supply.

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Scared as I watch the impending train wreck of a global economy that is being recklessly driven toward a fiscal and monetary cliff by its political masters safety valves welded shut, fuel being poured on the fire, desperately trying to outrun a disaster of their own making.

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The passive feature means they rely less on electrically driven pumps and valves, for safety, and more on systems designed to shut down plants safely in emergencies and to prevent operator error.

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America and operates a number of service centers, supply branches and sales offices through which it markets pipes, valves, fittings, safety and other maintenance products.

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The AP1000 has half the valves, 35% fewer safety-grade pumps, 80% less pipe and 85% less cable than existing plants.

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But the girls used one-way valves throughout the device as a safety measure.

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