The simple r-g assumption is one of the most important in debt dynamics: an r-g of greater than zero (when interest rates are greater than GDP growth) means that the debt stock increases over time.

简单的对（r-g）的假设是债务动态中最重要的部分之一。

youdao

Time spent in zero G changes the body: Astronauts come home with bone loss and weakness. But what happens in their heads?

失重会改变身体：宇航员回家时会有骨质流失和肌肉无力的感觉，但是他们的大脑里会发生什么呢？

youdao

A leak is indicated if usage does not drop to zero, at least for a period of time, during a given time interval (e. g., during a 24-hour period).

如果在给定时间间隔(例如在24小时的时段)内，至少一段时间用量未降至零，则指示有泄漏。

youdao

Earth-orientated sciences in a zero-g environment will always be its priority, and with six individuals living permanently on the station the amount of astronaut time dedicated to experimentation has now been raised to something like 70 hours a week.

BBC: Manned flight around Moon considered