To be termed a compound fracture, outside air with bacteria and debris are able to access the fracture site without skin or soft tissue serving as a barrier.

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People become infected when they breathe in air containing legionella bacteria.

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It comes after a Leeds University study has added to a growing body of evidence about the ability of bacteria to float on air currents.

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The water is combined is an air tight chamber with anaerobic digesters (bacteria) which take out about 70% of the bad stuff out of the water.

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This lifesaving machine is itself a threat, because bacteria can grow in the tubes that bring air to the baby's lungs.

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And then we listened to his chest and his chest was just filled with, you know, all kind of bacteria that was just - there's no air moving.

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Bacteria evolved the necessary chemistry to "fix" nitrogen from the air, about two billion years ago.

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By using atmospheric air and negative ions, a natural cleansing agent, it fights dirt and bacteria with nature's own weapon, he said.

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The microscopic whiskers can stop bacteria in a face mask or filter out water droplets in a hospital's air conditioner.

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