Artificial Pancreas as a Potential 'Cure' for Diabetes," March 23, 2004,
http://www.medtronic.com/newsroom/news_2004323a.html. Such devices require
a glucose sensor, an insulin
pump, and an automated feedback mechanism to monitor insulin levels (International Hospital Federation,
"Progress in Artificial Pancreas Development for Treating Diabetes,"
http://www.hospitalmanagement.net/informer/technology/tech10). Roche is also in the race to produce an
artificial pancreas by 2007. See http://www.roche.com/pages/downloads/science/pdf/rtdcmannh02-6.pdf.
41.
A number of models and simulations have been created based on analyses of individual neurons and
interneuronal connections.
Tomaso Poggio writes, "One view of the neuron is that it is more like a chip with
thousands of logical-gates-equivalents rather than a single threshold element," Tomaso Poggio, private
communication to Ray Kurzweil, January 2005.
See also T. Poggio and C. Koch, "Synapses That
Compute Motion,"
Scientific American
256 (1987): 46–
52.
C. Koch and T. Poggio, "Biophysics of Computational Systems: Neurons, Synapses, and Membranes," in
Synaptic Function
, G. M. Edelman, W. E. Gall, and W. M. Cowan, eds. (New York: John Wiley and Sons,
1987), pp. 637–97.
Another set of detailed neuron-level models and simulations is being created at the University of
Pennsylvania's Neuroengineering Research Lab based on reverse engineering brain function
at the neuron
level. Dr. Leif Finkel, head of the laboratory, says, "Right now we're building a cellular-level model of a small
piece of visual cortex. It's a very detailed computer simulation which reflects with some accuracy at least the
basic operations of real neurons. [My colleague Kwabena Boahen] has a chip that accurately models
the retina
and produces output spikes that closely match real retinae." See
http://nanodot.org/article.pl?sid=0l/12/18/1552221.
Reviews of these and other models and simulations at the neuron level indicate that an estimate of 10
3
calculations per neural transaction (a single transaction involving signal transmission and reset on a single
dendrite) is a reasonable upper bound. Most simulations use considerably less than this.
42.
Plans for Blue Gene/L, the second generation of Blue Gene computers, were announced in late 2001. The new
supercomputer, planned to be fifteen times faster than today's supercomputers and one twentieth the size, is
being built jointly by the National Nuclear Security Agency's Lawrence Livermore National Laboratory and
IBM. In 2002, IBM announced that open-source Linux had been chosen as the operating system for the new
supercomputers. By July 2003, the innovative processor chips for the supercomputer, which
are complete
systems on chips, were in production. "Blue Gene/L is a poster child for what is possible with the system-on-a-
chip concept. More than 90 percent of this chip was built from standard blocks in our technology library,"
according to Paul Coteus, one of the managers of the project (Timothy Morgan, "IBM's Blue Gene/L
Shows
Off Minimalist Server Design,"
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