A laser beam like the one pictured up top combines short and long pulses of light to identify individual molecules with a high degree of precision from a safe distance.

一道激光射线由或短或长的光脉冲组合而成，从而能在一个安全的距离高精度地辨别单个的分子。

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The report goes on to discuss the top-down and bottom-up approach to developing services (both are required to one degree or another).

报告继续讨论了自顶向下和自底向上两种开发服务的方式(或多或少两种都是必需的)。

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The challenge for the Japanese is to open up to individualism and more top-down leadership while retaining collectivism to some degree.

CNN: STORY HIGHLIGHTS

It is also instructive to keep in mind that all the large companies headed up by non-degree holders also invest heavily in recruiting top college graduates to acquire the talent they need to drive the future success of their organizations.

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