Weather conditions that drive this bizarre temperature surge have visited the Arctic before.

导致这种奇怪的气温飙升的天气条件以前也曾出现在北极地区。

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They concluded that the surge had improved security and economic conditions in areas where General Petraeus had concentrated his forces.

他们得出的结论是，在彼得雷乌斯将军部署重兵的地方，增兵计划改善了社会和治安环境。

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But with conditions improving for those who were never that badly affected to begin with, new hiring is less likely to lead to a surge of fresh optimism.

但是随着情形转好，对于这些一开始就受影响不大的岗位，新的招聘也不大可能带来多大的惊喜。

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"We have very high confidence that by that date conditions will permit us to end the surge and begin a gradual and responsible drawdown of U.S.forces."

VOA: standard.2009.12.08

Their conclusions: The "hurricane protection system" built by the Corps had serious design and construction flaws, baked into the system over 40 years under administrations of both parties, that caused catastrophic failure in more than 50 locations under storm surge conditions markedly less than the system was advertised to withstand.

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In healthy people, an adrenaline surge can trigger irregular heart rhythms and in those with heart conditions, the surge could trigger a heart attack.

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Back then, the report was seen as an initial check on whether the U.S. military surge was reducing violence enough to create conditions for political progress.

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