Just a quick list of interesting papers that caught my eye this week
(some of this earlier reported on or from the transhumantech list):
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.
Geocybernetics: Controlling a Complex Dynamical System Under Uncertainty, H.-J. Schellnhuber, J. Kropp, Naturwissenschaften Volume 85 Issue 9 (1998) pp 411-425
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, volume14, number 1, pages 134-140
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
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.
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
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
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.
Controlling complexity, Leon Poon and Celso Grebogi, Physical Review Letters, November 27, 1995 Volume 75, Issue 22, pp. 4023-4026
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! email@example.com 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