Asif Noorani, the founder of Dr. Cell Phone, a chain of repair shops in Texas, has also seen one iPad.

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Dr Thomas said sickle cell has suffered from a low profile and poor understanding among clinical staff.

BBC: Sickle cell hospital admissions cut

Using this technique doubled the efficiency of Dr Kamat's cell from 5% to 10% at ultraviolet wavelengths and he reckons it would create similar increases in efficiency in both plastic and dye-based cells.

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