"These difficult to reach populations frequently go underground and remain not visible to the medical delivery system,"

VOA: standard.2009.11.15

It is not only the laser-beam projectors and their visible cooling system with rotating vents that make the shimmering blue headlamps of the Concept GLA such an interesting feature.

ENGADGET: Mercedes-Benz GLA concept puts laser projectors in headlights, redefines SUV

More important still, there in the sky was a miniature Copernican system, visible to the aided eye.

NEWYORKER: Moon Man

Another reason that drugs get spotty results may be that some tumors are simply more visible to the immune system than others.

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