Malainey et al. find a possible explanation in late-eighteenth and early-nineteenth century accounts from three frontiersmen who had adapted to lean-meat diets during extended periods in the plains.

马莱内等人在18世纪末和19世纪初的三个前沿地区发现了一个可能的解释，这些前沿国家在平原上长期适应了瘦肉饮食。

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Only the periods between early March and late May, along with early September and late October are fit for climbing, among which less than 20 days are actually fine.

只有三月初到四月底以及九月初到十月底的这两段时间才适合登山，就算在这两段时间里，也不超过20天是好天气。

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A long-term graph of the Vix hints at cyclicality, with periods of great choppiness in the early and late 1990s book-ending an era of relative calm in the middle of the decade.

Vix的长期图像也暗示着周期性，1990s的早期和末期呈现大量的波浪，夹在中间的90年代中期却是一段相对平静的时期。

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Indeed, a casual look at the ratio of corporate profits to net assets since the early 1950s shows two peaks: in the mid-1960s and late-1990s, both periods of robust growth.

ECONOMIST: Has the tide turned for corporate profits?

Chicago killed all four San Jose power plays, all of which occurred in a span of under 14 minutes late in the second and early in the third periods.

NPR: Blackhawks Set NHL Record With 2-1 Win Over Sharks