人类的褪黑激素水平在夜晚上升，以响应黑暗和昼夜节律钟发出的信号。
In humans melatonin levels rise at night, in response to darkness and cues from the circadian clock.
Visa对于此次ipo时机的把握也许显示了这样一个信号，即尽管现在市场情况可能不会转好，但对于首次公开募股，也许是黑暗中难得露出的一点微光。
The timing of Visa's impending IPO is perhaps a sign that the firm believes that market conditions will not improve, but for now the IPO itself is a rare moment of light amid the gloom.
我们的身体依靠“睡眠信号”来入睡，其中一个信号就是黑暗。
Our bodies depend on 'sleep signals' to fall asleep and one of those signals is darkness.
应用推荐