You can use that behavior to tell that the user is not online by having a scheduled agent check the timestamp and reset the user's status when it turns old.

您可以利用此行为来判断用户没有在线，通过使用预定的代理来检查时间戳，并在出现更新的时间戳时重置用户状态。

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Turns out, those who were primed to think of mortality were much more likely to save the resource for future use by others.

结果证明，事先想过死亡问题的志愿者更倾向于节省能源，为未来做准备。

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But what if this salutary caution turns into an unwillingness to use force at all, even when it is called for by the national interest or on humanitarian grounds?

ECONOMIST: Lexington

Now turns to Google half a billion Android devices are in use and most are powered by Qualcomm chips, he says.

FORBES: Qualcomm CEO Paul Jacobs Delivers Opening Keynote at CES (Live)