Water harvesting in Death Valley: Conquering the arid wilderness

Korea is regarded as a "water-stressed nation." Although the country receives an annual precipitation of approximately 1,300mm, it is characterized by concentrated periods and specific regions, thereby giving rise to challenges ...

Do technological civilizations depend on atmospheric oxygen?

Nearly 2 million years ago a species of upright apes known as Homo erectus began to use fire. It was a gradual process, from opportunistic users of natural fires to masters able to craft flames from flint and tender. We are ...

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