Calabresi says his next step will be to look at changes in the fiber layer thickness in 100 patients over a period of three years.

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In each layer, electrons exist at a different level of energy, determined by the layer's thickness.

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Once the container is spinning at the correct speed (typically a few revolutions per minute), the mercury spreads out to form a layer less than a millimetre thick, and in such a way that variations in the thickness of the mercury layer compensate for the imperfect shape of the container.

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Stick the part in acid, run an electric current through it and we can increase the thickness of the layer by a factor of 20-40.

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Instead, the transistor is built up as a series of layers, deposited one at a time on the chip a process that allows the thickness of each layer to be controlled very accurately.

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When the thickness of the polymer layer was greater than 50 nm, essentially almost all the bacteria were killed.

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First, the team measured the thickness of the fluid layer between the toe pad and the Petri dish that the frog was standing on.

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