The pillow uses a kind of LED material below the surface.

该枕头的表面下使用了一种 LED 材料。

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The falling water level denoted the passing hour as it dipped below hour lines inscribed on the inner surface.

当下降的水位低于内表面刻下的小时线，表示经过了多少时间。

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In the laboratory, when the seal dives below the surface of the water and stops breathing, its heart beats more slowly, requiring less oxygen, and its arteries become constricted.

在实验室里，当海豹潜入到水面以下并停止呼吸时，它的心脏跳动得更慢，需要的氧气更少，动脉也会收缩。

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In true ASEAN style, the below-the-surface griping is unlikely to bubble up.

CNN: A 'BOLD' BAND OF BROTHERS

Scientists may not be able to explain the "boiler" at the south pole but they are already talking up the possibility that conditions there could allow for liquid water below the surface - with all the implications that might have.

BBC: NEWS | Science/Nature | Saturn moon delights and baffles

Dubbed Jellyfish 45, the home would feature a globe-shaped room fitted with acrylic view-ports below the surface.

FORBES: 10 Floating Homes Of The Future