Complexity Digest 2001.27

02-Jul-2001

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Content

  1. Brane New World, Nature
  2. Chaos Killed The Dinosaurs, Nature
  3. Chaotic Hysteresis and Systemic Economic Transformation: Soviet Investment Patterns, NDPLS
  4. Quantum Bargaining Games, arXiv
  5. New York 121 -- Is Sent To Russia To Stave Off Potato Crisis, Cornell Press Release
  6. From Double Bind to N-Bind: Toward a New Theory of Schizophrenia and Family Interaction, NDPLS
  7. Future Psychological Evolution, Dynamical Psychology
  8. Secrets Of An Acid Head, New Scientist
  9. Putting Numbers Into Words, BioMedNet
    1. Lip Service To Phantom Limbs, BioMedNet
  10. The Structure of Growing Social Networks, SFI Working Papers
  11. The Web Of Human Sexual Contacts, Nature
  12. Metazoan Inventions For Integrating Cells Into Tissues, Physiol. Rev
  13. Writing Gets A Rewrite, Science
  14. Researchers Undaunted In Complex Quest For Aids Vaccine Keay Davidson, The San Francisco Chronicle
  15. SIMPLIcity: Semantics-sensitive Integrated Matching for Picture Libraries, IEEE
  16. Regularities Unseen, Randomness Observed: Levels of Entropy Convergence, SFI Working Paper
  17. Crystal-Like Structure Of Photosystem I Providing Light Capturing And Electron Transfer, Nature
  18. Nitric Oxide And The Control Of Firefly Flashing, Science
    1. NO Helps Make Fireflies Flash, Science
    2. Why Do Fireflies Glow?, CNN Video
  19. Flickering Lights Foretell Glowing Networks, BBC News Online
  20. Links & Snippets
    1. Santa Fe Institute Working Papers
    2. Other Papers
    3. Announcements
      1. Complexity Digest Site Design Competition!
      2. Global Brain Conference Webcasting, (Today!)
      3. Other Announcements

  1. Brane New World, Nature Next Article Bookmark and Share

    Excerpt: Could this 'brane-world' concept unify gravity with nature's other fundamental forces? (…)

    Imagine a parallel universe in which the three familiar dimensions of space and one of time are replaced by alternative dimensions beyond our experience. Now imagine that multiple universes exist as membranes, or branes, through a multidimensional hyperspace. These additional dimensions could be the size of atoms, or infinitely large. We would never be able to enter them, yet they could have profound effects on the physics of our Universe.


  2. Chaos Killed The Dinosaurs, Nature Next Article Bookmark and Share

    Excerpt: A bizarre wobble 65 million years ago, perturbing the orbits of Mars, Earth and Mercury, may have caused the demise of the dinosaurs, new models of the Solar System suggest.

    The celestial upset could have disrupted the trajectories of asteroids - normally safely confined to asteroid belts -sending one or more careering into the Earth.

    The proposed wobble coincides with the Cretaceous-Tertiary (K-T) boundary, when an asteroid or comet is thought to have smashed into Earth, exterminating the dinosaurs.


  3. Chaotic Hysteresis and Systemic Economic Transformation: Soviet Investment Patterns, NDPLS Next Article Bookmark and Share

    Abstract: Economies making a transition from centrally planned socialism to market capitalism can experience chaotic hysteresis. This can arise from elements of the previous system persisting even as institutions are transformed with the system possibly experiencing chaos during this conflict. A model of investment cycles accompanied by technological stagnation shows this phenomenon which can be viewed from a cusp catastrophe perspective. Empirical tests of Soviet investment and construction data provide incomplete support for the cusp structure with chaos. Nonlinear structures are found with bifurcation effects for all cases and possibly chaotic dynamics for five-year lagged construction data.

  4. Quantum Bargaining Games, arXiv Next Article Bookmark and Share

    Abstract: We continue the analysis of quantum-like description of markets and economics. The approach has roots in the recently developed quantum game theory and quantum computing. The present paper is devoted to quantum bargaining games which are a special class of quantum market games without institutionalized clearinghouses.

    Excerpt: There have recently been important changes in the paradigms of economics: economists discuss the role of the Heisenberg uncertainty relation or even dare claim that quantum mechanics and mathematical economics are isomorphic. These shocking changes have probably been brought about by the emergence of econophysics. Research on quantum computation and quantum information allows to extend the scope game theory for the quantum world. Among various proposed qualitative scientific methods only quantum theory does not allow to take no account of the news phenomenon so persistent in social sciences. Therefore the quantum-like description of market phenomena has a remarkable chance of gaining favourable reception from the experts. On the other hand only thorough investigation may reveal if economics already is in or would ever enter the domain of quantum theory.

    Editor's Note: If human decisions can be traced to microscopic quantum events one would expect that nature would have taken advantage of quantum computation in evolving complex brains. In that sense one could indeed say that quantum computers are playing their market games according to quantum rules.


  5. New York 121 -- Is Sent To Russia To Stave Off Potato Crisis, Cornell Press Release Next Article Bookmark and Share

    Excerpt: Russia is teetering on the brink of a large-scale potato crisis ignited by the same virulent, fungal-like pathogen, Phytophthora infestans, more commonly called late blight, that was responsible for the 19th century Irish potato famine.

    But there is hope in the form of a blight-resistant potato variety, New York 121, which Cornell University scientists have provided to Russia for testing in the hopes of preventing food shortages. (...)

    Annually, Russia loses 4 million tons of potato, more than 10 percent of total production, due to late blight. Virulent strains of the pathogen are now spreading to important potato--producing areas in Russia and to Central and Eastern Europe. (...) The scientists meeting in Warsaw said that New York 121 is not a silver bullet to solve all of Russia's agricultural woes, but is a small, early step toward sustainability and modernization of a system that has long been at the mercy of pestilence. (...)


  6. From Double Bind to N-Bind: Toward a New Theory of Schizophrenia and Family Interaction, NDPLS Next Article Bookmark and Share

    Abstract: Double Bind Theory has long been discredited as a viable theoretical framework to understand the relationship between schizophrenia and family interaction. Since research continues to indicate that the family environment plays a crucial role in the development and/or maintenance of the disorder, a reconsideration of the status of Double Bind is both necessary and timely. This paper utilizes a Nonlinear Dynamical Systems framework to bring the theory up to date with current dynamical thinking, and renames the resulting model N-Bind theory. The premises of N-Bind theory are discussed, and the symptoms of schizophrenia are described in light of the theory. The compatibility of N-Bind theory with the Vulnerability-Stress model is discussed, and a procedure is proposed to test the two hypotheses which postulate on different levels of analysis that Binds are more likely to occur in families with than without a schizophrenic member. Some of the implications for treatment and prevention are considered, should the theory be supported by empirical evidence.


  7. Future Psychological Evolution, Dynamical Psychology Next Article Bookmark and Share

    Abstract: Humans are able to construct mental representations and models of possible interactions with their environment. They can use these mental models to identify actions that will enable them to achieve their adaptive goals. But humans do not use this capacity to identify and implement the actions that would contribute most to the evolutionary success of humanity. In general, humans do not find motivation or satisfaction in doing so, no matter how effective the actions might be in evolutionary terms. From an evolutionary perspective, this is a significant limitation in the psychological adaptability of humans. This paper sets out to identify the new psychological capacity that would be needed to overcome this limitation and how the new capacity might be acquired.

    Contributing Editor's Note: Natural evolution has no "goal" but to adapt to a dynamic environment. Even if we will be able to control "consciously" our evolution, it would be towards a goal determined by the society. Will artificial evolution allow us to adapt to our dynamic environment? It should, since we have been manipulating our environment for some millennia already.


  8. Secrets Of An Acid Head, New Scientist Next Article Bookmark and Share

    Excerpts: (…) Cowan and his team think they have found where hallucinations really come from. And there's nothing transcendental about it. (…) "It's just the innate tendency of the brain to make patterns when it goes unstable."

    Cowan's goal is to find out how the brain makes sense of the visible world-(…). In the process, he may learn how it breaks down in other extraordinary conditions, such as migraine headaches. Hallucinations could even offer a route to the more profound depths of the mind, to emotions and conscious thought.


  9. Putting Numbers Into Words, BioMedNet Next Article Bookmark and Share

    Excerpt: The brain circuits for mathematical approximations and for exact calculations have been shown to be separate and distinct. The architecture for the former is specialized and also appears to exist in monkeys, but the latter is embedded in language systems and may be uniquely human.(…)

    Gerstmann Syndrome - with symptoms including acalculia or impaired calculation, agraphia or impaired writing, poor ability to distinguish between right and left and to name or differentiate fingers - might reflect brain damage that falls in the spot where these four spatial skills overlap, he adds. The mosaic theory might also explain our tendency - as children, at least - to count on our fingers.


    1. Lip Service To Phantom Limbs, BioMedNet Next Article Bookmark and Share

      Excerpt: German researchers may have found a way to prevent the cortical reorganization that occurs following amputation, and block the phantom limb pain associated with it.

      Phantom limb pain is associated with a cortical reorganization such that, typically, the representation of the face and particularly the lips in the brain's primary somatosensory cortex expands. It "pushes" into the area that used to represent the amputated limb - the so-called deafferented area - so that if a patient's lip area is stimulated he or she may report pain in that limb, even though it no longer exists.


  10. The Structure of Growing Social Networks, SFI Working Papers Next Article Bookmark and Share

    Abstract: We propose some simple models of the growth of social networks, based on three general principles: (1) meetings take place between pairs of individuals at a rate which is high if a pair has one or more mutual friends and low otherwise; (2) acquaintances between pairs of individuals who rarely meet decay over time; (3) there is an upper limit on the number of friendships an individual can maintain. Using computer simulations, we find that models that incorporatge all of these features reproduce many of the features of real social networks, including high levels of clustering or network transitivity and strong community structure in which individuals have more links to others within their community than to individuals from other communities.

  11. The Web Of Human Sexual Contacts, Nature Next Article Bookmark and Share

    Excerpts: One unambiguous type of connection, however, is sexual contact, and here we analyse the sexual behaviour of a random sample of individuals to reveal the mathematical features of a sexual-contact network. We find that the cumulative distribution of the number of different sexual partners in one year decays as a scale-free power law that has a similar exponent for males and females.

    the web of sexual contacts has a scale-free structure indicates that strategic targeting of safe-sex education campaigns to those individuals with a large number of partners may significantly reduce the propagation of sexually transmitted diseases.

    • The Web Of Human Sexual Contacts, Fredrik Liljeros, Christofer R. Edling, Luis A. Nunes Amaral, H. Eugene Stanley, Yvonne Aberg, Nature 411, 907 - 908 (21 June 2001)

  12. Metazoan Inventions For Integrating Cells Into Tissues, Physiol. Rev Next Article Bookmark and Share

    Abstract: The spectrin-based membrane skeleton of the humble mammalian erythrocyte has provided biologists with a set of interacting proteins with diverse roles in organization and survival of cells in metazoan organisms. This review deals with the molecular physiology of spectrin, ankyrin, which links spectrin to the anion exchanger, and two spectrin-associated proteins that promote spectrin interactions with actin: adducin and protein 4.1. The lack of essential functions for these proteins in generic cells grown in culture and the absence of their genes in the yeast genome have, until recently, limited advances in understanding their roles outside of erythrocytes. However, completion of the genomes of simple metazoans and application of homologous recombination in mice now are providing the first glimpses of the full scope of physiological roles for spectrin, ankyrin, and their associated proteins. These functions now include targeting of ion channels and cell adhesion molecules to specialized compartments within the plasma membrane and endoplasmic reticulum of striated muscle and the nervous system, mechanical stabilization at the tissue level based on transcellular protein assemblies, participation in epithelial morphogenesis, and orientation of mitotic spindles in asymmetric cell divisions. These studies, in addition to stretching the erythrocyte paradigm beyond recognition, also are revealing novel cellular pathways essential for metazoan life. Examples are ankyrin-dependent targeting of proteins to excitable membrane domains in the plasma membrane and the Ca2+ homeostasis compartment of the endoplasmic reticulum. Exciting questions for the future relate to the molecular basis for these pathways and their roles in a clinical context, either as the basis for disease or more positively as therapeutic targets.

  13. Writing Gets A Rewrite, Science Next Article Bookmark and Share

    Excerpt:. Most researchers now agree that writing is less the invention of a single talented individual than the result of a complex evolutionary process stretching back thousands of years before the first hard evidence of writing surfaced in Mesopotamia, Egypt, and the Indus River valley about 3300 B.C. But a lack of fresh data, the reluctance of museum curators to allow potentially destructive testing of critical artifacts, and the limitations of radiocarbon dating are making it difficult to sort out the origins of writing.

  14. Researchers Undaunted In Complex Quest For Aids Vaccine Keay Davidson, The San Francisco Chronicle Next Article Bookmark and Share

    Excerpt: Why is it taking so long to develop an AIDS vaccine? In June 1990, Dr. Wayne Koff was one of the speakers at an AIDS conference in San Francisco. (...) he ran the AIDS vaccine program at the National Institutes of Health - and he was very excited by recent developments in animal models of AIDS. (...) he declared at the conference: "We have cracked open the door, and next year we're going to knock it down," suggesting an AIDS vaccine was close at hand. (...) To laypeople, the progress toward an AIDS vaccine may seem excruciatingly slow. In fact, such seemingly pokey progress is typical of the history of medicine.

  15. SIMPLIcity: Semantics-sensitive Integrated Matching for Picture Libraries, IEEE Next Article Bookmark and Share

    Contributing Editor's Note: Retrieving digital images - the way people look at and understand pictures - promises faster, more accurate image database searches. The new approach considers no information other than the image itself. Just as a person shown a picture of a horse can extract the features characteristic of horses and then identify other pictures that contain horses, so does the new approach. The new system retrieves relevant images from an image database or the web on the basis of automatically-derived image features or content.

    Abstract: The need for efficient content-based image retrieval has increased tremendously in many application areas such as biomedicine, military, commerce, education, and Web image classification and searching. We present here SIMPLIcity (Semantics-sensitive Integrated Matching for Picture LIbraries), an image retrieval system, which uses semantics classification methods, a wavelet-based approach for feature extraction, and integrated region matching based upon image segmentation. As in other region-based retrieval systems, an image is represented by a set of regions, roughly corresponding to objects, which are characterized by color, texture, shape, and location. The system classifies images into semantic categories, such as textured-nontextured, graph-photograph. Potentially, the categorization enhances retrieval by permitting semantically-adaptive searching methods and narrowing down the searching range in a database. A measure for the overall similarity between images is developed using a region-matching scheme that integrates properties of all the regions in the images. Compared with retrieval based on individual regions, the overall similarity approach (1) reduces the adverse effect of inaccurate segmentation, (2) helps to clarify the semantics of a particular region, and (3) enables a {\it simple} querying interface for region-based image retrieval systems. The application of SIMPLIcity to several databases, including a database of about 200,000 general-purpose images, has demonstrated that our system performs significantly better and faster than existing ones. The system is fairly robust to image alterations.


  16. Regularities Unseen, Randomness Observed: Levels of Entropy Convergence, SFI Working Paper Next Article Bookmark and Share

    Abstract: We study how the Shannon entropy of sequences produced by an information source converges to the source's entropy rate. We synthesize several phenomenological approaches to applying information theoretic measures of randomness and memory to stochastic and deterministic processes by using a hierarchy of derivatives of Shannon entropy convergence. This leads, in turn, to natural measures of (i) apparent memory stored in a source and (ii) the amounts of information that must be extracted from observations of a source in order (a) for it to be optimally predicted and (b) for an observer to synchronize to it. One consequence of ignoring these structural properties is that the missed regularities are converted to apparent randomness. We demonstrate that this problem arises particularly for small data sets; e.g., in settings where one has access to a relatively few, short measurement sequences.

    Contributing Editor's Note: While some of this material has appeared previously (and is dutifully cited by the authors), the synthesis presented here is both self-contained and easier to understand than the previously existing, widely scattered literature. Another useful feature of the paper is the application of its entropy convergence measures to a series of sample data sources, showing how they can be used to experimentally infer important features of a hidden data source. One such source is the "RRXOR process", consisting of triples of two randomly chosen binary bits, followed by their "Exclusive-OR (XOR), followed by a different, independently chosen realization, etc. Applying the techniques of the paper to this source, but without using any prior knowledge as to its nature, the triplet structure was identified.


  17. Crystal-Like Structure Of Photosystem I Providing Light Capturing And Electron Transfer, Nature Next Article Bookmark and Share

    Excerpts. The crystal structure of photosystem I from the thermophilic cyanobacterium Synechococcus elongatus provides a picture at atomic detail of 12 protein subunits and 127 cofactors comprising 96 chlorophylls, 2 phylloquinones, 3 Fe4S4 clusters, 22 carotenoids, 4 lipids, a putative Ca2+ ion and 201 water molecules. The structural information on the proteins and cofactors and their interactions provides a basis for understanding how the high efficiency of photosystem I in light capturing and electron transfer is achieved.

    Contributing Editor's Comment. From a complex macromolecule to an integrated 3D crystalline matrix: the high-resolution structure obtained indicates to the high level of integration of numerous and chemically different components into the 3D crystalline matrix. The number and the variety of components is indicative, including components like metal ions (Fe and Ca), elements (S), and water molecules. Demonstration of such an integration into highly-organized 3D architecture is in accordance with E. Shroedinger' vision of living matter as a "aperiodic crystal". The aperiodic crystal provides a 3D infrastructure for spatial control of structure and functions.


  18. Nitric Oxide And The Control Of Firefly Flashing, Science Next Article Bookmark and Share

    Excerpts: We report that light production by fireflies can be stimulated by nitric oxide (NO) gas in the presence of oxygen and that NO scavengers block bioluminescence induced by the neurotransmitter octopamine. (…). These results suggest that NO synthesis is a key determinant of flash control in fireflies.

    Firefly courtship depends on a remarkable flash communication system involving precisely timed, rapid bursts of bioluminescence. The duration of a single flash is typically a few hundred milliseconds, and flash patterns vary among firefly species.

    Editor's Note: Nitric oxide also plays an important role in the human central nervous system. Note that the flash duration is of the same time-scale as the activity duration of human neuronal cell assemblies during a "binding event".


    1. NO Helps Make Fireflies Flash, Science Next Article Bookmark and Share

      Excerpt: Neurobiologists have long known that the firefly's abdomen contains a lantern made of specialized cells,. (…) A nerve signal called octopamine controls the flash pattern, (…). But how it does so has been unclear, as the nerve ending isn't in direct contact with the photocytes. (…)

      When it's time to flash, however, the NO concentration increases in the air-duct cells and diffuses over the mitochondria, briefly shutting down this oxygen barrier. (…) "the lantern in and of itself turns off the NO reaction," (…) light inhibits NO.


    2. Why Do Fireflies Glow?, CNN Video Next Article Bookmark and Share


  19. Flickering Lights Foretell Glowing Networks, BBC News Online Next Article Bookmark and Share

    Excerpt: Fluorescent lights could soon be shedding bits of data as well as illumination. US scientists have found a way to make the flicker of fluorescent lights carry data. If widely adopted, the technology could be used to set up cheap data networks inside buildings, or could be used to help the disabled and the blind or deaf cope with unfamiliar surroundings.

    Early trials of the system have shown how it can help disabled patients find their way around the confusing corridors of a busy Boston hospital. (...)


  20. Links & Snippets Next Article Bookmark and Share

    1. Santa Fe Institute Working Papers Next Article Bookmark and Share

      1. Fractal Geometry of Spin-Glass Models, J. F. Fontanari and P. F. Stadler, SFI WP 01-06-034
      2. Stochasticity in Transcriptional Regulation: Origins, Consequences and Mathematical Representations, Thomas B. Kepler and Timothy C. Elston, SFI WP 01-06-033
      3. The Structure of Growing Social Networks , Emily M. Jin, Michelle Girvan, and M. E. J. Newman, SFI WP 01-06-032
      4. If You're So Smart, Why Aren't You Rich? Belief Selection in Complete and Incomplete Markets , Lawrence Blue and David Easley, SFI WP 01-06-031
      5. A Simple Model of Epidemics with Pathogen Mutation, Michelle Girvan, Duncan S. Callaway, M. E. J. Newman, and Steven H. Strogatz, SFI WP 01-05-030
      6. The Topology of Technology Graphs: Small World Patterns in Electronic Circuits , Ramon Ferrer i Cancho, Christiaan Janssen and Ricard V. Solé , SFI WP 01-05-029
      7. Recovery After Mass Extinction: Evolutionary Assembly in Large-Scale Biosphere Dynamics , Ricard V. Solé, José M. Montoya, and Douglas H. Erwin , SFI WP 01-05-028
      8. The Peacock, the Sparrow, and the Evolution of Human Language , Carl T. Bergstrom, Rustom Antia, Szabolcs Számadó, and Michael Lachmann, SFI WP 01-05-027
      9. Quantum Walks on the Hypercube , Cristopher Moore and Alexander Russell , SFI WP 01-05-026
      10. Are Randomly Grown Graphs Really Random? , D. S. Callaway, J. E. Hopcroft, J. M. Kleinberg, M. E. J. Newman, and S. H. Strogatz, SFI WP 01-05-025
      11. Field Theory of a Reaction-Diffusion Model of Quasispecies Dynamics , Romualdo Pastor-Satorras and Ricard V. Solé , SFI WP 01-05-024

    2. Other Papers Next Article Bookmark and Share

      1. Instruments Aboard CONTOUR Spacecraft Will Provide First Surface 'Fingerprint' Of Comet Nucleus, Cornell Press Release, 6/12/01
      2. Nonlinear Dynamics Estimation of EEG Signals Accompanying Self-Paced Goal-Directed Movements, Juliana Dushanova, David Popivanov, Nonlinear Dynamics, Psychology, and Life Sciences, 5 (4): 325-344, 10/2001
      3. Conductance Switching in Single Molecules Through Conformational Changes, Z. J. Donhauser, B. A. Mantooth, K. F. Kelly, L. A. Bumm, J. D. Monnell, J. J. Stapleton, D. W. Price Jr., A. M. Rawlett, D. L. Allara, J. M. Tour, P. S. Weiss, Science vol.292, n5525, pp.2303-2307(Jun 22 2001)
      4. Quinones as the Redox Signal for the Arc Two-Component System of Bacteria, Dimitris Georgellis, Ohsuk Kwon, Edmund C. C. Lin, Science vol 292, n5525, (22 Jun 2001), pp. 2314-2316.
      5. Phylogenetic Analyses Do Not Support Horizontal Gene Transfers From Bacteria To Vertebrates, Michael J. Stanhope, Andrei Lupas, Michael J. Italia, Kristin K. Koretke, Craig Volker, James R. Brown, Nature v.411, pp.940-944 (21 June 2001)
      6. A Neuron-Glia Signalling Network In The Active Brain, Paola Bezzi and Andrea Volterra, Current Opinion in Neurobiology, 2001, 11:3387-394

    3. Announcements Next Article Bookmark and Share

      1. Complexity Digest Site Design Competition! Next Article Bookmark and Share

        We have had essentially the same site layout since November 1999. And it seems to work. But in the interest of embracing change and evolution, we want to consider modifications or a compete redesign. The people who have the most to gain from a redesign are the ComDig readers. And, given the experience of the community we served, you also have the most to offer.

        To that end, we propose to run a design competition during the summer accepting entries of suggested layouts, structural ideas and anything that you think we should develop. The successful entry will have a monetary reward, offer to be hired to complete the details and the satisfaction of seeing the work implemented.

        Anyone, anywhere, any age is welcome. Submissions can be sent to: editor@comdig.org


      2. Global Brain Conference Webcasting, (Today!) Next Article Bookmark and Share

        We post short, edited video clips from the sessions and comments by speakers and participants on the Complexity Digest Webcasting page at: http://www.comdig.de/Conf/GB0


      3. Other Announcements Bookmark and Share


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