19世纪末的中国已经日益腐朽，20世纪末的中国开始渐渐繁荣。

China at the end of the 19th century was deteriorating, but it was beginning to prosper at the end of the 20th century.

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这种情况上世纪90年代末发生在日本，21世纪初再次发生，但从20世纪50年代末以来在大多西方国家并没发生这种情况。

This had come to pass in Japan in the late 1990s and again in the early 2000s, but had not occurred in most Western countries since the late 1950s.

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研究者们将一种至今经常被忽视的效应纳入模型。这个效应就是由德国物理学家阿诺德•索末菲尔德在20世纪30年代提出的索末菲尔德效应。

The researchers included in their model a hitherto-neglected effect proposed by a German physicist, Arnold Sommerfeld, in the 1930s.

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