But prolonged viewing may result in an aching head, according to Dr Michael Rosenberg, an ophthalmology professor at Northwestern University Feinberg School of Medicine in Chicago.

但芝加哥西北大学费恩柏格医学院的眼科学教授迈克尔·罗森堡博士说，长时间观看3d电影可能会导致头痛。

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Records of those who paid the head tax are still available for viewing in the National Archives of Canada.

那些交了人头税的人，其档案至今还可以在加拿大国家档案馆查阅到。

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I bow my head in awe in front of our creator son and Esu, who are working so relentlessly under full power, just with small breaks to relax from viewing all the mess down there on the planet.

我在我们的创造者（基督迈克）和伊苏面前心怀敬畏，他们在如此竭尽所能、不遗余力的工作着，仅是偶尔从注视星球上混乱的一切中停下来放松一下。

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This will certainly make you want to head for your own viewing spot to watch the sunset.

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They also tested whether the learning process was conscious by distracting the subjects during the video viewing - the volunteers were asked to do simple arithmetic sums in their head, for example.

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Vodafone is also running several pilots, says Richard Saggers, the head of its mobile advertising unit, in which subscribers receive free content in exchange for viewing ads.

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