But the experts from Codelco, the state copper producer, who have headed the rescue operation, are still taking no unnecessary chances.

不过，来自国家矿企codelco的救援负责专家却不想冒任何不必要的风险。

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According to the absolute humidity to adjust relieves the room temperature fluctuations in the relative humidity change which causes the unnecessary missed operation increasing the power consumption.

采用先进节能的绝对湿度控制方式，根据绝对湿度来调节，不会因机房温度波动使相对湿度变化，造成不必要的加湿、除湿误操作，增大功耗。

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'All women should be screened before they try for a baby. And they should be made aware of the operation that could save them unnecessary miscarriages.'

在偿试怀孕一名孩子之前，应对所有的妇女进行筛选。应使她们认识到这种手术，可以免去她们很多不必要的流产。

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The study, published in the Lancet, could spare other women the trauma and worry of an unnecessary operation, as well as the distressing news that they may be at risk from cancer.

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"We've always felt that the whole SNH operation and the cull was completely unnecessary, " she said.

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Opponents claim that at best, it is an unnecessary ritual, and that at worst, it is an operation that proves detrimental to the physical and psychological health of the patient.

CNN: Health