While constructing it, they doped the quantum well layers with precise quantities of impurities. (newscientist.com)
The Number Sense games, including a snazzy - looking iPhone version of Numberbonds, are intended to nurture the abilities that, Butterworth contends, are the root of numerical cognition and the core deficit of dyscalculia — manipulating precise quantities. (scientificamerican.com)
Previous studies of Amazon tribes who lack words for numbers greater than three — or, in the case of the Pirahã, for any numbers at all — had shown that they struggle to understand precise quantities when numbers are relatively large. (newscientist.com)