Most of what we know about "habitability" -- the ability of an environment to host and support life -- has been studied under the very different conditions on Earth.

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Looking ahead, I can see more and more instances where I'll disagree with the president on very fundamental issues -- the issues of choice, the direction of the judiciary, tax and spending decisions, missile defense, energy and the environment, and a host of other issues, large and small.

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"The work environment provides a host of potential partners, " researcher Adrian J.

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The defining political question of this decade will not be Iraq or Afghanistan, or the environment or any of a host of other problems.

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But the multi-billion-dollar effort is straining the host city's resources, environment and nerves.

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There are a host of chemicals found in the typical office environment that may cause long-term health issues.

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The President has tasked the Secretary to develop and devise a process for a long-term Gulf restoration plan that includes all of the stakeholders -- states, local communities, Gulf Coast residents, a whole host of -- those that have significant equities in the environment and the ecosystem.

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As well as contributing to global warming, those emissions -- as well as a host of other toxic by products of Chinese industrialization -- are having a catastrophic effect on the health and environment of the nation that is producing them.

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