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Is dust really people? - Video học tiếng Anh
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Is dust really people?
Is dust really people?
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0:00
(finger squeaking)
0:01
- Is dust just people?
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You may have heard, like me, that the dust
0:06
that collects around your house
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is mostly made of dead human skin cells.
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Is that really true?
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Well, as usual, the answer's more complicated
0:14
and more interesting, but that's also not totally wrong.
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Humans shed about a gram of skin every day.
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We actually replace our entire outer epidermal layer
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every two to four weeks.
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That means that your dead body does make up
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a significant portion of the dust on your windowsill,
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but dust is also much more than that.
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Under a microscope,
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dust contains a whole world of shapes and colors.
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It's almost beautiful in a really gross way.
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Now, one famous study of households in the Midwest
0:40
found that a third of dust comes from stuff inside the home.
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In addition to skin cells from you and your pets,
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that includes food debris and fibers from clothing
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and furniture, plus microscopic dust mites
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just feeding on all that debris
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from you and your belongings.
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But the other two thirds of household dust
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actually comes from outside the house,
0:57
including dirt, pollen, feces, eh,
1:00
environmental pollutants.
1:01
There's even trace amounts of space minerals from meteorites
1:04
and distant exploding stars that just shower down to Earth.
1:07
Dust is basically just a microcosm
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of your local environment.
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In fact, it's even used by forensic scientists
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to help solve crimes.
1:14
The DNA entombed in dust from a person of interest
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can help provide valuable information
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about where they may have traveled.
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So dust is people. It's just more than that, too.
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Guess that puts a whole new meaning
1:25
on cleaning up after yourself.
1:27
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