档案Archive: www.comdig.org, 欧洲镜像European Mirror: www.comdig.de
亚洲镜像Asian Mirror: http://www.phil.pku.edu.cn/resguide/comdig/ (Chinese GB-Code)
“我认为下一世纪将是复杂性的世纪”"I think the next century will be the century of complexity." 霍金 Stephen Hawking
Excerpt: (...) a team led by Phaedon Avouris of IBM reported making a circuit out of a single semiconducting nanotube. By draping the nanotube over a pair of electrodes and independently controlling their behavior, the team coaxed the device to work like a simple circuit called an inverter, another basic building block for more complex circuitry.
In addition to carrying out rudimentary processing, the IBM circuit demonstrated another key advantage: "gain," the ability to turn a weak electrical input into a stronger output (...).
- Breakthrough Of The Year:Molecules Get Wired, Robert F. Service, Science Dec 21 2001: 2442-2443
Excerpt: Molecular-scale circuitry - which could open the way for ultrafast computers and disease-fighting micromachines in your bloodstream - ranks at the top of Science's annual list of the year's 10 biggest scientific achievements. This year's runners-up include RNA chemistry, the decoding of the human genome, the appearance of anti-cancer "smart bombs" and the growing consensus on the causes of climate change.
(...) the rapid advances in the field of nanotechnology, which incorporates molecular-scale computers, self-assembling micromachines and the fabrication of carbon nanotubes and nanowires
- Nanocircuits Lead 2001's List Of Breakthroughs, MSNBC News, 01/12/20
Excerpt: The World Technology Awards have been created to honour those individual leaders or, at times, co-equal teams from across the globe who most contribute to the advance of emerging technologies of all sorts for the benefit of business and society. We especially seek to honour those innovators who have done work recently which has the greatest likely future significance and impact over the long-term... and who will likely become or remain "key players" in the technological drama unfolding in coming years.
- The World Technology Awards, The World Technology Network , 01/12/27
2. A Golden Age Of Cosmology, Edge [Video]
Editor's Note: Alan Guth introduced the concept of an "inflationary" universe that basically treats the Big Bang as a phase transition, thereby introducing concepts from complex systems to cosmology.
Excerpts: ( ) we have to assume that there's a new component of energy in the universe that we didn't know existed before. This new component is usually referred to as "dark energy." ( ) It's a component of energy which in fact is very much like the repulsive gravity matter I talked about earlier - the material that drives the inflation in the early universe. ( ), but the universe today appears very definitely to be starting to accelerate again under the influence of this so-called dark energy.
3. Software, Property & Human Civilization, Edge [Video]
Excerpts: It looks like biological complexity comes from the interplay of several different fields. Physics, Evolution, and Game theory. What's possible is determined by a set of rules. There are the immutable rules, systems that obey these rules, and create new systems which operate with rule-like behaviors that we think of as computation. Evolution enables a kind of exploration of the possible, , putting together components in various ways (¡K).Physics (the rules) determine whats possible. Evolution (the variation) explores the possible. The Game determines what persists.
4. Sharing the Garden, Science
Excerpts: There is no doubt that these human impacts are large, but it can be difficult to say how large in a way that is accurate, meaningful, ( ).
Among the most useful measures proposed to date is the fraction of Earth's total plant growth or net primary production (NPP) that is appropriated by humans. NPP is the energy transferred from plants to other levels in the food chain. ( )
In human-modified regions where NPP exceeds that of the pristine vegetation, subsidies of nutrients and often water and pesticides are also high.
- Sharing the Garden, Christopher B. Field, Science 2001 294: 2490-2491
Excerpts: Previous global estimates of the human impact on terrestrial photosynthesis products depended heavily on extrapolation ( ). Here, we estimated this impact with the use of recent data, many of which were collected at global and continental scales. ( ) We estimate that humans appropriate 10 to 55% of terrestrial photosynthesis products. This broad range reflects uncertainty in key parameters and makes it difficult to ascertain whether we are approaching crisis levels in our use of the planet's resources. Improved estimates will require high-resolution global measures within agricultural lands and tropical forests.
- Human Appropriation of Photosynthesis Products, Stuart Rojstaczer, Shannon M. Sterling, Nathan J. Moore, Science 2001 294: 2549-2552
5. Revving Up Auto Branding, The Mckinsey Quarterly
Summary: US car companies spend upward of $40 billion a year on marketing-more than any other US industry. Yet the combined market share of the Big Three continues to slide. Why? The authors of this piece place the blame on a loss of brand identity. As cars become more alike, carmakers have often made price the main reason for choosing one brand over another-the classic trap of a commoditizing industry and the destroyer of healthy profit margins.
- Revving Up Auto Branding, Anjan Chatterjee, Matthew E. Jauchius, Hans-Werner Kaas, Aurobind Satpathy , The Mckinsey Quarterly, 2002 Number 1
6. Computer Crack Funnier Than Many Human Jokes, New Scientist
Excerpts: The Laugh Lab survey is being conducted through a web site, on which members of the public are invited to submit favorite jokes and rate other submissions. They are also asked to contribute information about themselves.
( ) computers used to create the entries are programmed to play with the meaning of words but are not able to judge funniness themselves. He suggests that, were a computer able to do this, it could perhaps be considered intelligent. "It might be the ultimate Turing test,"( )
7. Image Processing: Fractals In Pixellated Video Feedback, Nature
Excerpts: We demonstrate that pixellated, but otherwise unmodified, video feedback with M > 1 can lead to fractal patterns ( ). Previous experiments with [magnification, Ed.] M > 1 produced non-stationary complex patterns - for example, rapidly rotating planet-like, fractal-looking structures suspected of being connected to pixels. Pixels were also described as acting like the 'cells' of a cellular automaton, a class of abstract machine capable of producing fractal patterns, and simulations of video feedback on a matrix model - in which the matrix elements acted like square pixels - produced stationary fractal spirals.
- Image Processing: Fractals In Pixellated Video Feedback, J Courtial, J Leach, M J Padgett, Nature 414, 864 (2001)
8. Windows XP Security Bug "Very Serious" Says Microsoft, New Scientist
Excerpts: A software glitch with Windows XP (¡K) leaves users in unprecedented danger (¡K).
The hole is in a service called Universal Plug and Play, which comes as standard with Windows XP. The bug allows a malicious hacker to gain complete control over a computer. (¡K)
Microsoft representatives say that the fault poses an unprecedented risk because a user is vulnerable as soon as they connect to the internet - no other action is required. (¡K)
Microsoft touted Windows XP as its most secure operating system (¡K).
- Windows XP Security Bug "Very Serious" Says Microsoft, Will Knight, New Scientist, 01/12/21
- Windows XP Vulnerable To 'Serious' Attacks, CNN, 01/12/20
9. How Does The Brain Generate Computation?, Edge [Video]
Excerpt: Whenever nature has created systems that seem to be open-ended and generative, they've used some kind of system with a discrete set of recombinable elements. ( ) For example, many organisms seem to be capable of quite simple statistical computations, such as conditional probabilities that focus on local dependencies: if A, then B. Lots of animals seem capable of that. But when you step up to the next level in the computational hierarchy, one that requires recursion, you find great limitations both among animals and human infants.
10. Connectionism Reconsidered: Minds, Machines and Models, CogPrints
Abstract: In this paper the issue of drawing inferences about biological cognitive systems on the basis of connectionist simulations is addressed. In particular, the justification of inferences based on connectionist models trained using the backpropagation learning algorithm is examined. First it is noted that a justification commonly found in the philosophical literature is inapplicable. Then some general issues are raised about the relationships between models and biological systems. A way of conceiving the role of hidden units in connectionist networks is then introduced. This, in combination with an assumption about the way evolution goes about solving problems, is then used to suggest a means of justifying inferences about biological systems based on connectionist research.
- Connectionism Reconsidered: Minds, Machines and Models , Berkeley, Istvan, CogPrints. 2001
- Contributed by Carlos Gershenson
11. Pattern-Motion Responses In Human Visual Cortex, Nature Neuroscience
Abstract: Physiological models of visual motion processing posit that 'pattern-motion cells' represent the direction of moving objects independent of their particular spatial pattern. We performed fMRI experiments to identify neuronal activity in the human brain selective for pattern motion. A protocol using adaptation to moving 'plaid' stimuli allowed us to separate pattern-motion responses from other types of motion-related activity within the same brain structures (&). Reducing the perceptual coherence of the plaids yielded a corresponding decrease in pattern-motion responsivity, providing evidence that percepts of coherent motion are closely linked to the activity of pattern-motion cells in human MT+.
12. Response Dynamics Of Entorhinal Cortex, Brain Research
Abstract: The generation of oscillatory activity may be crucial to brain function. The coordination of individual neurons into rhythmic and coherently active populations is thought to result from interactions between excitatory and inhibitory cells mediated by local feedback connections. By using extracellular recording wires and silicon microprobes to measure electrically evoked damped oscillatory responses at the level of neural populations in the entorhinal cortex, and by using current-source density analysis to determine the spatial pattern of evoked responses, we show that the propagation of activity through the cortical circuit and consequent oscillations in the local field potential are dependent upon background neural activity.
- Response Dynamics Of Entorhinal Cortex In Awake, Anesthetized And Bulbotomized Rats, Ahrens, K. F. , Freeman, W. J. ,Brain Research 911(2), 2001
- Contributed by Atin Das
13. Efforts To Transform Computers Reach Milestone, NYTimes
Excerpt: By bombarding the molecules with a precise sequence of electromagnetic pulses, the experimenters carefully flipped the atoms back and forth between 1 and 0, carrying out the steps of Dr. Shor's algorithm.
Rapidly factoring numbers the size of those used in cryptography would probably require delicate manipulation of tens of thousands of atoms, and the slightest disturbance could cause the calculation to come undone. But with the principle of quantum factoring proved on paper and now demonstrated in the laboratory, some scientists are optimistic.
- Efforts To Transform Computers Reach Milestone, George Johnson, NYTimes, 01/12/20
Excerpts: The number of steps any classical computer requires in order to find the prime factors of an l-digit integer N increases exponentially with l, at least using algorithms known at present. Factoring large integers is therefore conjectured to be intractable classically ( ). Quantum computers, however, could factor integers in only polynomial time, using Shor's quantum factoring algorithm. ( ) experimental demonstration of this algorithm has proved elusive. Here we report an implementation of the simplest instance of Shor's algorithm: factorization of N = 15
- Experimental Realization Of Shor's Quantum Factoring Algorithm Using Nuclear Magnetic Resonance, L M K Vandersypen, M Steffen, G Breyta, C S Yannoni, M H Sherwood, I L Chuang, Nature 414, 883 - 887 (2001)
14. Horses Damp The Spring In Their Step, Nature
Excerpts: The muscular work of galloping in horses is halved by storing and returning elastic strain energy in spring-like muscle-tendon units. ( ) tuned to stretch and recoil at 2.5 strides per second. This mechanism is optimized by unique musculoskeletal adaptations: the digital flexor muscles have extremely short fibres and significant passive properties, whereas the tendons are very long and span several joints. ( ) Furthermore, we show that the digital flexor muscles ( ) are ideally arranged to damp these high-frequency [40 Hz, Ed.] oscillations in the limb.
- Horses Damp The Spring In Their Step, A M Wilson, M P Mcguigan, A Su, A J Van Den Bogert
Excerpt: More than 95 per cent of today's male thoroughbreds are descended from just one stallion, and more than three-quarters of modern racehorse genes come from just 30 ancestors, new research reveals.
- Racehorse Relations, John Whitfield, Nature, 01/12/18
15. Pattern Formation And Traveling Waves In Myxobacteria: Theory And Modeling, PNAS
Abstract: Recent experiments have provided new quantitative measurements of the rippling phenomenon in fields of developing myxobacteria cells. These measurements have enabled us to develop a mathematical model for the ripple phenomenon on the basis of the biochemistry of the C-signaling system, whereby individuals signal by direct cell contact. The model quantitatively reproduces all of the experimental observations and illustrates how intracellular dynamics, contact-mediated intercellular communication, and cell motility can coordinate to produce collective behavior. This pattern of waves is qualitatively different from that observed in other social organisms, especially Dictyostelium discoideum, which depend on diffusible morphogens.
- Pattern Formation And Traveling Waves In Myxobacteria: Theory And Modeling, Oleg A. Igoshin, Alex Mogilner, Roy D. Welch, Dale Kaiser, George Oster, PNAS 2001;98 14913-14918
Excerpts: Cells in the early stages of starvation-induced fruiting body development migrate in a highly organized periodic pattern of equispaced accumulations that move as traveling waves. Two sets of waves are observed moving in opposite directions with the same wavelength and speed. To learn how the behavior of individual cells contributes to the wave pattern, fluorescent cells were tracked within a rippling population. ( ) This model of traveling waves represents a new mode of biological pattern formation that depends on cell-contact interactions rather than reaction diffusion.
- Cell Behavior In Traveling Wave Patterns Of Myxobacteria, Roy Welch and Dale Kaiser, PNAS 2001;98 14907-14912
16. Report: Space Sugar Sweetened Primordial Soup, CNN
Excerpt: The discovery of sugar and several related organic compounds in two rare meteorites offers fresh evidence that key building blocks to life originated in outer space, according to a new NASA study. ( )
And last year, NASA astronomers announced they had spotted a compound similar to table sugar near the center of the Milky Way.
But the new finding is the first of sugary organic compounds in primordial space rocks recovered on Earth.
- Report: Space Sugar Sweetened Primordial Soup, Richard Stenger, CNN, 01/12/20
Excerpts: The much-studied Murchison meteorite is generally used as the standard reference for organic compounds in extraterrestrial material. Amino acids and other organic compounds important in contemporary biochemistry are thought to have been delivered to the early Earth by asteroids and comets, where they may have played a role in the origin of life. ( ) We conclude from this that polyols were present on the early Earth and therefore at least available for incorporation into the first forms of life.
- Carbonaceous Meteorites As A Source Of Sugar-Related Organic Compounds For The Early Earth,G Cooper, N Kimmich, W Belisle, J Sarinana, K Brabham, L Garrel, Nature 414, 879 - 883 (2001)
17. The Reliability Theory Of Aging And Longevity, J. Theoretical Biology
Excerpts: The theory explains why mortality rates increase exponentially with age (the Gompertz law) in many species, by taking into account the initial flaws (defects) in newly formed systems. It also explains why organisms "prefer" to die according to the Gompertz law, while technical devices usually fail according to the Weibull (power) law. Theoretical conditions are specified when organisms die according to the Weibull law: organisms should be relatively free of initial flaws and defects. The theory makes it possible to find a general failure law ( )
18. Can Engineered Bacteria Help Control Cancer?, PNAS
Excerpts: Hypoxia and anoxia are pathophysiologic characteristics of most solid tumors. For nearly 150 years, nonpathogenic, anaerobic bacteria ( ) have been investigated as treatments for experimental and human tumors with mixed success. In recent years, there has been a renewed interest in using these bacteria as innovative delivery vehicles for gene therapy. ( ) Vogelstein and coworkers have created a new strain of anaerobic bacteria, devoid of its toxic genes, that leads to dramatic and prolonged regression of subcutaneous tumors when systematically administered with conventional drugs.
- Can Engineered Bacteria Help Control Cancer?, Rakesh K. Jain, Neil S. Forbes, PNAS, Vol. 98, Issue 26, 14748-14750, December 18, 2001
Excerpts: Current chemotherapeutic approaches for cancer are in part limited by the inability of drugs to destroy neoplastic cells within poorly vascularized compartments of tumors. We have here systematically assessed anaerobic bacteria for their capacity to grow expansively within avascular compartments of transplanted tumors. ( ) When ( ) administered together with conventional chemotherapeutic drugs, extensive hemorrhagic necrosis of tumors often developed within 24 h, resulting in significant and prolonged antitumor effects. This strategy, called combination bacteriolytic therapy (COBALT), has the potential to add a new dimension to the treatment of cancer.
- Combination Bacteriolytic Therapy For The Treatment Of Experimental Tumors, Long H. Dang, Chetan Bettegowda, David L. Huso, Kenneth W. Kinzler, Bert Vogelstein, PNAS 2001 98: 15155-15160.
19. Complex Challenges: Global Terrorist Networks
Editor's Note: After having witnessed elderly ladies having their cosmetic utensils confiscated at a US airport security check I asked one of the security inspectors if he would recognize plastic explosives if I had some in my carry-on luggage. The answer was that they were not instructed to look for plastic explosives.
Last week the quick thinking of a flight attendant and the collective action of several passengers in combination with the lack of intelligence of the would-be terrorist (fortunately he didn't try to light his sneakers in the bathroom) prevented another airplane disaster. Mr. Reid didn't fit the profile of a cold-blooded terrorist and still he could get hold of sophisticated C4 and smuggle it on an airplane even after he has gone through considerable efforts to raise red flags. One might wonder if current security measures really have improved the chance to prevent a sophisticated terrorist to blow-up a plane in a suicide mission.
Excerpt: The plastic explosive that a passenger allegedly tried to detonate aboard a trans-Atlantic American Airlines flight last week was "very, very sophisticated," ( )
Officials say Richard Reid hid 10 ounces of PETN-based material, a version of the plastic explosive C4 that is very sensitive to heat and friction, in each of his shoes when he boarded Flight 63 in Paris on December 22. ( )
Investigators, the official noted, have also found a safety fuse -- black powder packed inside a cord that is attached to and designed to detonate the explosive.
20. Links & Snippets
20.1 Other Papers
- Nonlinear Thinker - Technology And Design, Daintry Duffy, Darwin Mag, 01/12
- Independent and Redundant Information in Nearby Cortical Neurons, Daniel S. Reich, Ferenc Mechler, and Jonathan D. Victor, Science 2001 December 21; 294: 2566-2568
- Circadian Rhythms:A Time To Rest: Clock Signal Identified, Barinaga, Marcia, Science 2001 294: 2453
- Pharmacogenomics: The Promise of Personalized Medicine, Mancinelli L, Cronin M, Sadee W., AAPS PharmSci 2000;2(1):E4
- Hitting the Surface-Softly,Daniel J. Auerbach, Science 2001 294, pp. 2488-2489
- Chemically Induced Electronic Excitations at Metal Surfaces, Science
- Control Analysis for Autonomously Oscillating Biochemical Networks, Biophys. J
- Complexities Of The DNA Base Excision Repair Pathway For Repair Of Oxidative DNA Damage, Mitra S, Boldogh I, Izumi T, Hazra TK., Environ Mol Mutagen 2001;38(2-3):180-190
- Computational Complexity of Multiple Sequence Alignment with SP-Score, J Comput Biol.
- Fractal Dimension Of Trabecular Bone,.Chappard D, Legrand E, Haettich B, Chales G, Auvinet B, Eschard JP, Hamelin JP, Basle MF, Audran M., J Pathol 2001 Nov;195(4):515-521
- From Self-Assembly Of Life To Present-Day Bacteria: A Possible Role For Nanocells, FEMS Microbiol Rev.
- Bizarre Squid Discovered Near Ocean Floor, New Scientist
- Worldwide Observations of Remarkable Deep-Sea Squids, Science
- Ball Lightning Scientists Remain In The Dark, New Scientist
- 2001 Set To Be Second Warmest Year On Record, Nicola Jones, New Scientist, 01/12/19
- A Probabilistic Symmetric Encryption Scheme For Very Fast Secure Communication Based On Chaotic Systems Of Difference Equations, S. Papadimitriou, T. Bountis, S. Mavroudi & A. Bezerianos, Int. J. Bifurcation and Chaos, Vol. 11, No. 12 pp. 3107-3115, (2001)
- Acquiring Languages: Two For The Price Of One?, L. Wagner, Trends In Cognitive Sciences, Volume 5, Issue 12 pp. 509, December 2001
- Ultrastructure Of Acetylcholine Receptor Aggregates Parallels Mechanisms Of Aggregation, D. D, Kunkel, L. K. Lee,J. Stollberg ,BMC Neuroscience 2001 2: 19,10 Dec 2001
- Anatomic Subdivisions In Human Temporal Cortical Neuronal Activity Related To Recent Verbal Memory, G A Ojemann, J Schoenfield-McNeill & D P Corina, Nature Neuroscience, Vol 5, No 1 pp 64 - 71, January 2002
- Rational Competitive Analysis, Moshe Tennenholtz, arXiv. Paper ID: cs.AI/0112015. 01/12/13
- 'The Stirling Engine-Refrigerator: Rich Pedagogy from Applied Physics, Randall Peters, arXiv, v1 19 Dec 2001
- Defining the Undefinable: The Living Cell, Natalie Angier , NYTimes, 01/12/18
20.2 Conference Announcements
- Complex Systems, Modeling Nonlinear Natural and Human Systems, Hawaii International Conference On System Sciences, HICSS-35, Hawaii, 02/01/07-10
- 1st Biennial Seminar on Philosophical, Methodological & Epistemological Implications of Complexity Theory, La Habana, Cuba, 02/01/07-11
- Topics in Nonlinear Dynamics, Collective Phenomena and Complexity: Dynamical Model Formulation, Analysis and Symmetry, Canberra, Australia, 02/01/21-02/01
- Managing Complex Health Care Organizations In A Complex World, NECSI, Cambridge, MA, 02/02/04-05
- ASPS [American Studies Project at Skeria] Seminar, Globalization and Business Cultures, Skellefteå, Sweden, 02/02/15-
- Physik Sozio-Oekonomischer Systeme, German Phys Soc, Regensburg, Germany, 02/03/11-15
- Capturing Business Complexity with Agent-Based Modeling and Simulation, SFI, Argonne National Laboratory, Il. 02/03/04-08
- AIS'2002: Towards Component-Based Modeling and Simulation, Lisbon, Portugal, 02/04/07-10
- World Conference NL 2002 - Networked Learning in a Global Environment: Challenges and Solutions for Virtual Education, Berlin, Germany, 02/05/01-04
- International Conference on Complex Systems (ICCS2002), NECSI, Nashua, NH, 02/06/9-14
- International Conference SocioPhysics, ZIF - Bielefeld, Germany, 02/06/06-09
- 7th International Conference on Music Perception & Cognition - ICMPC7, Sydney, 02/07/17-21
- Self-Organisation and Evolution of Social Behaviour, Monte Verità, Switzerland, 02/09/08-13
- Complex Systems (CS02) Complexity with Agent-based Modelling, Chuo University, Tokyo, Japan, 02/09/10-12
- 3rd Intl NAISO Symposium on Engineering Of Intelligent Systems (EIS 20020), Malaga, Spain, 02/09/24-27
- ACRI 2002, 5th Intl Conf on Cellular Automata for Research and Industry, Geneva, Switzerland, 02/10/09-11
- Artificial Life VIII, UNSW, Sydney, Australia, 02/12/09-13