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RANDI KAYE, CNN CORRESPONDENT: We take our shoes off, remove our laptops, and toss our bottled water all in the name of safety. But are we any safer today than we were before 9/11? Not exactly, says Bruce Schneier, author and security technologist. B
This is Scientific American's 60-Second Science. I'm Steve Mirsky. Got a minute?. [Spray sound.] Killing bugs? No. [Spray sound.] Deodorizing the bathroom? No. [Spray sound.] Checking for explosives, yes. Because chemists at the University of Califor
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Independence Day 词汇典故:独立日 Hello and welcome to the VOA Learning English program Words and Their Stories. Independence Day is a huge celebration in the United States. People celebrate by having parades and picnics and usually end the day
By Catherine Maddux Washington 07 March 2006 watch Africa report While experts worry about a decline in much of the industrialized world's population, sub-Saharan Africa is among the few places where
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