历史上的今天-Today in History 2012-02-28

（单词翻译）

 Feb 28th, 1953, in Britain, scientists say and they found the double helix structure of DNA¹, the molecule² that contains the human genes³. Years later, Francis Crick describes this discovery that he and fellow scientist James Watson made. “Biological systems are the result of evolution and they produce very complicated things. Now the reason of DNA looks so beautiful and simple; it goes right back to near the origins of life.” 1993, start of the arm standoff at the Branch Davidian compound in Waco, Texas. Federal agents try to arrest religious leader David Koresh for stock piling guns and explosives. That sparks a shoot-out which kills four agents and six of Koresh’s Davidian followers⁴. The standoff ends 51-days later when the compound burns to the ground, killing⁵ nearly 80 people. 1986, Sweden’s Prime Minister Olof Palme is shot to death in central Stockholm. His murder remains⁶ unsolved.