Perhaps the U-bend is merely an expression of the effect of external circumstances.

也许u型轨迹只是外部环境造成影响的一种表示方法。

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Life is not a long slow decline from sunlit uplands towards the valley of death.It is, rather, a U-bend.

生命不是一段长长的从阳光普照的高地缓慢地下落到死亡低谷的旅程，而是一个U型曲线。

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Since then, interest in the U-bend has been growing. Its effect on happiness is significant-about half as much, from the nadir of middle age to the elderly peak, as that of unemployment.

此后，人们对马蹄形趋势的关注日益增长，它对幸福感的作用十分显著，从处于最低端的中年时期到达随后的顶峰年纪，正如失业率趋势一样，且具有全球普遍性。

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She also said evidence of petrol was found in water taken from a sink u-bend at the house in Allenton.

BBC: Derby death blaze: Fuel 'found on accused man's clothes'

And, like New Delhi, Islamabad showed no readiness to bend to U.S. pressure and sign the Comprehensive Test Ban Treaty.

CNN: The India Tilt

Until now, the collection of factors cited as bringing on the angst have included societal and economic pressures that exert psychological forces strong enough to bend our lives into the famous U-shaped curve of happiness.

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