Using the lab service account is highly recommended, but not mandatory because you can also use local accounts on each machine.

强烈建议使用实验室服务帐户，但不强制使用，因为您还可以在每台计算机上使用本地帐户。

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If you operate within electricity, gas and emissions industries you'll know that it will soon be mandatory for individuals and businesses to account their carbon usage.

如果您在经营电力，天然气和有工业排放的产业，相信您知道，个人和企业将必须考虑碳排放的问题。

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To put that in perspective, all the countries now under mandatory Kyoto cuts account for just 27 percent of global CO2 emissions.

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In addition, some workers might see a mandatory contribution to their personal unemployment-support account as a long-term investment, not as a tax.

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Proceeds will be held in a restricted account, as terms include a mandatory redemption covenant tied to closing of the merger by Jan. 17, 2014.

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