Within a half-mile from ground zero, death from radiation poisoning will occur within twelve hours.

在核爆点半英里内，辐射中毒引起的死亡会在十二小时内发生。

《柯林斯英汉双解大词典》

That zero equals death.

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"Our goal is to get to zero deaths because each alcohol-impaired death is preventable, " NTSB Chairman Deborah Hersman said.

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Calabrese says that many poisons follow, instead, a U-shaped curve: The death rate goes down as the dose climbs from zero to a certain small amount, what you could call the optimal exposure.

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