It is unclear whether the antioxidants in grapeseed oil penetrate the skin sufficiently to benefit the skin, dermatologists say.

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The recording electrodes can be carried by a skull cap, and nothing has to penetrate the skin.

ECONOMIST: Bionics (I)

And so -- but apparently the ones that are being tested right now by all the big laboratories, they only can be used for skin cancer or places where the light can penetrate fairly close to the surface.

WHITEHOUSE: Backyard Discussion on Women and the Economy