最上面比较暗的冰层是去年冬天的雪，而中间比较亮的部分形成于去年夏天，最底部比较暗的部分又是更早一年冬天的雪。

The uppermost dimmer layer is snow from last winter, the bright layer in the center is last summer, and the dimmer layer at bottom is the winter before that.

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这种激光器的相反工作模式才是它真正的新奇之处，其中大部分时间光线是打开的，但它在很短的闪烁及非常短暂的暗脉冲里关闭。

"What's really novel is that this laser works in the opposite mode, where most of the time the light is on, but it turns off in very brief flashes, very brief dark pulses," said Wiener.

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另一种设想是暗物质和暗能量之间的联系会改变宇宙的结构，因为宇宙结构严重依赖于它的各种构成成分，包括黑暗部分。

Another idea is that a connection between dark matter and dark energy would alter the growth of cosmic structures, which depends delicately on the composition of the universe, including its dark side.

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If your have good eyesight from the distance that you're at you can see the vessels leading out of the heart and into the lungs, and the lungs are these darker spaces within the ribcage.

如果你的视力足够好的话,你们能看到,由心脏发出血管,进入到肺部,肺是胸腔里这片比较暗的部分

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