From: Anders Sandberg (asa@nada.kth.se)
Date: Fri Nov 06 1998 - 09:03:08 MST
Just a quick list of interesting papers that caught my eye this week
(some of this earlier reported on or from the transhumantech list):
* Beta-amyloid precursors as memory enhancers
* Geocybernetics: controlling the world
* Tisse-engineering of large tissues
* Growing neurons on patterned substrates
* Quantum key distribution through air
* NP=P if QM is nonlinear
* The street performer protocol for funding public works
* Networked schools
* Controlling complexity
Memory-enhancing effects of secreted forms of the beta-amyloid
precursor protein in normal and amnestic mice, H. Meziane, J. Dodart,
C. Mathis, S. Little, J. Clemens, S. M. Paul and A. Ungerer
Proc Natl Acad Sci U S A, 95:21, pages 12683--8, Oct 13, 1998
In Alzheimer's disease plaques of so called beta-amyloid protein form
in the brain. It has been shown that this is some kind of derivative
of a couple of precursor proteins that are used in the normal
brain. It seems that these precursors have many fun properties,
including being memory enhancing. This seems to hold for several
different memory tasks in short-term and long-term memory at a range
of very low doses (0.05-5000 pg intracerebroventricularly). It seems
that the precursors play some kind of role in memory, most likely
rather important. It also means that we have *another* family of
memory enhancing substances to play with.
Biology
Geocybernetics: Controlling a Complex Dynamical System Under
Uncertainty, H.-J. Schellnhuber, J. Kropp, Naturwissenschaften Volume
85 Issue 9 (1998) pp 411-425
(http://link.springer.de/link/service/journals/00114/bibs/8085009/80850411.htm)
A systems analysis of the large scale interaction between the natural
environment and human activities; the authors argue that it may be
possible to develop a science of "geocybernetics" for controlling this
interaction in order to achieve desired results. By using detailled
models, control of chaotic processes and implementing fuzzy control
strategies (dependent upon the desired goals, such as minimizing the
risk of catastrophic change, maximizing human benefit, retaining
options, or combinations of different goals) it might be possible to
regulate the combined human + nature system. Contains references to
various interesting projects (such as regulating el nino or controlled
algae blooms to eat carbon dioxide) and a discussion of how to
formulate the vague environmental-ethical goals into stringent systems
theory. Overall many good ideas, even if the authors right at the end
fall for the systems theory temptation of calling for a central
regulator (maybe we are starting to see a split here between 'old
school' centralized cybernetics and 'new school' networked,
complexity-embracing cybernetics?).
Development of technologies aiding large-tissue engineering,
P. Eiselt, B. S. Kim, B. Chacko, B. Isenberg, M. C. Peters,
K. G. Greene, W. D. Roland, A. B. Loebsack, K. J. Burg, C. Culberson,
C. R. Halberstadt, W. D. Holder, D. J. Mooney Biotechnol Prog, volume
14, number 1, pages 134-140
(http://pubs.acs.org/isubscribe/journals/bipret/jtext.cgi?bipret/14/i01/abs/bp970135h.html)
A discussion of how to create large artificial tissues. The problems
include creating a structure the cells can grow on that is both
biodegradable, strong enough to not collapse when implanted and a good
growth substrate for the cells, and how to make blood vessels grow
into the implant so the cells can thrive. They did some experiments
with lactide and glycolide scaffoldings, and made smooth muscle cells
grow on them. By putting microspheres with vascular endothelial growth
factor (VEGF) into the scaffolding they got blood vessels to grow into
the implant.
Neurite outgrowth and growth cone morphology on micropatterned
surfaces, H. C. Tai and H. M. Buettner, Biotechnol Prog, 14:3, 364-70,
May-Jun 1998
(http://pubs.acs.org/isubscribe/journals/bipret/jtext.cgi?bipret/14/i03/abs/bp980035r.html)
Growing neurons on surfaces is interesting from a transhuman point of
view, especially if they can be made to grow in the right pattern. Tai
and Buettner investigated how patterns of laminin affected the growth
of cultured neurons, and found that they indeed did tend to grow along
the stripes, but became somewhat smaller than neurons cultured on free
laminin surfaces.
Quantum Weirdness
Practical Free-Space Quantum Key Distribution over 1 km,
W. T. Buttler, R. J. Hughes, P. G. Kwiat, S. K. Lamoreaux, G. G. Luther, G. L. Morgan, J. E. Nordholt, C. G. Peterson, and C. M. Simmons
Physical Review Letters, 81:15, 3283-3286, 1998
(http://ojps.aip.org/journal_cgi/getabs?KEY=PRLTAO&cvips=PRLTAO000081000015003283000001&gifs=No
Quantum cryptography seems to become ever more practical; this article
describes how keys have been exchanged over an outdoor optical path
around one kilometer long during nighttime. A quite fun feat, so far
most experiments have been based on optical fibers. They also discuss
the possibility of ground-satellite communication this way.
Nonlinear Quantum Mechanics Implies Polynomial-Time Solution for
NP-Complete and \#P Problems, Daniel S. Abrams and Seth Lloyd
Physical Review Letters, 1998, 81_18, 3992-3995
(http://ojps.aip.org/journal_cgi/getabs?KEY=PRLTAO&cvips=PRLTAO000081000018003992000001&gifs=No
If there are small nonlinearities in quantum mechanics, then quantum
computers can solve NP-complete problems in polynomial time. There is
no evidence whatsoever that QM is nonlinear, but this paper at least
shows that physics really can have implications for computer
science.
Economics / Society
The Street Performer Protocol, J. Kelsey and B. Schneier, The Third
USENIX Workshop on Electronic Commerce Proceedings 1998
http://www.counterpane.com/street_performer.html
Copyrights seems to become increasingly hard to enforce; information
is by its nature easy to copy. This causes a problem for creating
works of art, programs and other information products that can be
pirated - how does the author get paid? The SPP is based on the idea
that the author announces that she will create a certain work (or more
likely, has created and will release) when a certain amount of money
has been placed in eschrow. People place donations in the eschrow, and
when the announced amount has been gathered the work is
made/released. This can be extended to include publishers, banking and
funding of public works. Quite fun idea, might be tested in the
shareware field at first.
The Living Network of Schools Owned by Teachers and Students,
Stanislaw D. Glazek, http://xxx.lanl.gov/abs/physics/9804005
An alternative school system, composed of a network of teachers and
students forming distributed school system. The network is divided
into teams, which may consist of students, teachers or both, and each
team is assigned to learn something and will exist for as long as the
task is not completed. Teams form classes, classes form schools,
schools form districts and so on. Teachers hold stock in the schools,
and will get dividends depending on the overall performance of the
school. They will also earn extra by producing good educational
materials or doing a good job. Students own credits, which are gained
by passing standard tests, exams, writing reports or scientific papers
(there is no firm division between basic education and university
level research; the system is intended to work on many levels,
allowing students to gradually move upwards). Overall, this seems to
be an interesting idea, even if it is (as the author points out)
half-baked as yet. It might be sufficiently flexible and encouraging
of inquiry and development to work well for a transhuman community.
Complexity
Controlling complexity, Leon Poon and Celso Grebogi, Physical Review
Letters, November 27, 1995 Volume 75, Issue 22, pp. 4023-4026
(http://ojps.aip.org/journal_cgi/getabs?KEY=PRLTAO&cvips=PRLTAO000075000022004023000001&gifs=No
A bit old-hat these days, but it is nice to see that chaotic systems
can be controlled (see the geocybernetics paper). This paper is about
the reason why this works and how to control the noisy double rotor
map.
-- ----------------------------------------------------------------------- Anders Sandberg Towards Ascension! asa@nada.kth.se http://www.nada.kth.se/~asa/ GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y
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