Complexity Digest 2003.40

06-Oct-2003

  1. Life and the Art of Networks, Science
    1. Biological Networks: The Tinkerer as an Engineer, Science
    2. Social Insect Networks, Science
    3. Communication in Neuronal Networks, Science
    4. A Bacterial Cell-Cycle Regulatory Network Operating in Time and Space, Science
  2. Stock Market Traders Show Signs Of Zero Intelligence, Nature
    1. The Predictive Power Of Zero Intelligence In Financial Markets, arVix
  3. On the Origin of Power Law Tails in Price Fluctuations, SFI Working Papers
    1. Predict the Future? You Can Bet on It, NYTimes
  4. A Study On Virtual Market Model For e-Marketplace Server, Elec. Comm. Res. & Appl.
  5. Universal Mechanisms in the Growth of Voluntary Organizations, arXiv
    1. Volunteering Leads To Rock–Paper–Scissors Dynamics In A Public Goods Game, Nature
  6. Are More People Cheating?, NYTimes
  7. Leading Takes More Than A Vision, Darwin Mag
  8. Reducing Underage Drinking Requires Cooperative Effort, National Academies
  9. Active Internet Traffic Filtering: Real-time Response to Denial of Service Attacks, arXiv
    1. Confessions of a Spam King, NYTimes
  10. How to Find That Needle Hopelessly Lost in the Haystack, NYTimes
  11. Biological Basis For Creativity Linked To Mental Illness, ScienceDaily
    1. Long-Term Retention Of The Differential Values Of Arabic Numerals By Chimpanzees, Animal Cognition
  12. Neuromaturation Of Human Locomotion Revealed By Non-Dimensional Scaling, Experi. Brain Res.
  13. An Age of Instability, Science
    1. An Age-Induced Switch to a Hyper-Recombinational State, Science
  14. Now Hear This, Quickly, NYTimes
  15. Applied Physics: Spintronics Gets A Magnetic Flute, Nature
  16. Uniform Resonant Chaotic Mixing In Fluid Flows, Nature
  17. Particle Formation by Ion Nucleation in the Upper Troposphere and Lower Stratosphere, Science
  18. Interactions Between Ecological And Climatic Systems In Northern Africa, Ecosystems
  19. Complex Challenge: Terrorist Networks
    1. Government Seeks Next-Generation Biosensors, The Scientist
    2. U.S. Uses Terror Law to Pursue Crimes From Drugs to Swindling, NYTimes
    3. Building Intelligence to Fight Terrorism, James Steinberg, Mary, Brookings Policy Brief
  20. Links & Snippets
    1. Other Publications
    2. Webcast Announcements
    3. Conference & Call for Papers Announcements
    4. ComDig Announcement: New ComDig Archive in Beta Test
    5. Special Announcement: Artists Explore Complex Systems, Federal Reserve Board
  1. Life and the Art of Networks, Science Bookmark and Share

    Excerpts: Biologists are striving to move beyond a "parts list" to more fully understand the ways in which network components interact with one another to influence complex processes. Thus attention has turned to the analysis of networks that operate at many levels. At the scale of networks of interacting proteins that govern cellular function, the flagellated bacterium Caulobacter crescentus has been a model system for cell cycle regulation (...). The design principles for efficient coordination of cells that work together in organ systems are also under scrutiny.
    • Source: Life and the Art of Networks
      [ http://www.sciencemag.org/cgi/content/summary/301/5641/1863 ], Barbara R. Jasny, L. Bryan Ray, Science Sep 26 2003: 1863

    1. Biological Networks: The Tinkerer as an Engineer, Science Bookmark and Share

      Excerpt: François Jacob pictured evolution as a tinkerer, not an engineer (1). Engineers and tinkerers arrive at their solutions by very different routes. Rather than planning structures in advance and drawing up blueprints (as an engineer would), evolution as a tinkerer works with odds and ends, assembling interactions until they are good enough to work. It is therefore wondrous that the solutions found by evolution have much in common with good engineering design (2). This Viewpoint comments on recent advances in understanding biological networks using concepts from engineering.
      • Source: Biological Networks: The Tinkerer as an Engineer
        [ http://www.sciencemag.org/cgi/content/full/301/5641/1866 ], U. Alon, Science Sep 26 2003: 1866-1867.

    2. Social Insect Networks, Science Bookmark and Share

      Excerpts: Social insect colonies have many of the properties of adaptive networks. The simple rules governing how local interactions among individuals translate into group behaviors are found across social groups, giving social insects the potential to have a profound impact on our understanding of the interplay between network dynamics and social evolution. (...), social insects such as wasps, ants, and honeybees provide a powerful system for examining how network dynamics contribute to the evolution of complex biological systems. (...) have key network attributes that appear consistently in complex biological systems, (...).
      • Source: Social Insect Networks
        [ http://www.sciencemag.org/cgi/content/full/301/5641/1867 ], Jennifer H. Fewell, Science Sep 26 2003: 1867-1870.

    3. Communication in Neuronal Networks, Science Bookmark and Share

      Excerpts: Brains perform with remarkable efficiency, are capable of prodigious computation, and are marvels of communication. We are beginning to understand some of the geometric, biophysical, and energy constraints that have governed the evolution of cortical networks. (...), nature has optimized the structure and function of cortical networks with design principles similar to those used in electronic networks. The brain also exploits the adaptability of biological systems to reconfigure in response to changing needs. (...) The global connectivity in the cortex is very sparse, (...) reduces the volume occupied by long-range connections.
      • Source: Communication in Neuronal Networks
        [ http://www.sciencemag.org/cgi/content/full/301/5641/1870 ], Simon B. Laughlin, Terrence J. Sejnowski, Science Sep 26 2003: 1870-1874

    4. A Bacterial Cell-Cycle Regulatory Network Operating in Time and Space, Science Bookmark and Share

      Excerpts: Transcriptional regulatory circuits provide only a fraction of the signaling pathways and regulatory mechanisms that control the bacterial cell cycle. The CtrA regulatory network, important in control of the Caulobacter cell cycle, illustrates the critical role of nontranscriptional pathways and temporally and spatially localized regulatory proteins. The system architecture of Caulobacter cell-cycle control involves top-down control of modular functions by a small number of master regulatory proteins with cross-module signaling coordinating the overall process. Modeling the cell cycle probably requires a top-down modeling approach (...).
      • Source: A Bacterial Cell-Cycle Regulatory Network Operating in Time and Space
        [ http://www.sciencemag.org/cgi/content/full/301/5641/1874 ], Harley H. McAdams, Lucy Shapiro, Science Sep 26 2003: 1874-1877

  2. Stock Market Traders Show Signs Of Zero Intelligence, Nature Bookmark and Share

    Excerpts: Market traders are not mindless. But if they were we might not notice the difference, claim J. Doyne Farmer, of the Santa Fe Institute in New Mexico, and co-workers. Their theoretical model assumes that traders place orders at random rather than on the basis of shrewd calculation and observation of economic trends. It reproduces some of the statistical features of financial markets. Traders, it suggests, are rather like ants swarming chaotically through the guts of a great clock, barely affecting its ability to tick.
    • Source: Stock Market Traders Show Signs Of Zero Intelligence
      [ http://www.nature.com/nsu/030922/030922-6.html ], Philip Ball, Nature Science Update, 24 September 2003

    1. The Predictive Power Of Zero Intelligence In Financial Markets, arVix Bookmark and Share

      Excerpts: Standard models in economics are based on intelligent agents that maximize utility. However, there may be situations where constraints imposed by market institutions are more important than intelligent agent behavior. We use data from the London Stock Exchange to test a simple model in which zero intelligence agents place orders to trade at random. (...). The agreement between model and theory is excellent, explaining 96% of the variance of the bid-ask spread across stocks and 76% of the price diffusion rate. We also study the market impact function, describing the response of prices to orders. (...) Thus, it appears that the price formation mechanism strongly constrains the statistical properties of the market, playing a more important role than the strategic behavior of agents.
      • Source: The Predictive Power Of Zero Intelligence In Financial Markets
        [ http://xxx.arxiv.org/abs/cond-mat/0309233 ], Farmer, J. D., Patelli, P. & Zovko, I. I., arXiv, 03/09/09

  3. On the Origin of Power Law Tails in Price Fluctuations, SFI Working Papers Bookmark and Share

    Abstract: In a recent Nature paper, Gabaix et al. presented a theory to explain the power-law tail of price fluctuations. The main points of their theory are that volume fluctuations, which have a power-law tail with exponent roughly -1.5, are modulated by the average market impact function, which describes the response of prices to transactions. They argue that the average market impact function follows a square root law, which gives power-law tails for prices with exponent roughly -3. We demonstrate that the long-memory nature of order flow invalidates their statistical analysis of market impact, and present a more careful analysis that properly takes this into account. This makes it clear that the functional form of the average market impact function varies from market to market, and in some cases from stock to stock. In fact, for both the London Stock Exchange and the New York Stock Exchange the average market impact function grows much slower than a square root law; this implies that the exponent for price fluctuations predicted by modulations of volume fluctuations is much too big. We find that for LSE stocks the distribution of transaction volumes does not even have a power law tail. This makes it clear that volume fluctuations do not determine the power law tail of price returns.
    • Source: On the Origin of Power Law Tails in Price Fluctuations
      [ http://www.santafe.edu/sfi/publications/wpabstract/200309052 ], J. Doyne Farmer, Fabrizio Lillo, DOI: SFI-WP 03-09-052

    1. Predict the Future? You Can Bet on It, NYTimes Bookmark and Share

      Excerpt: But in fact, marketplaces like the Foresight Exchange and the one envisioned by Admiral Poindexter are darlings of economists, who describe their workings with sophisticated terms like "price discovery," "opinion aggregation" or "risk analysis." They argue that the constant betting is an efficient way for distilling the opinions of many people into one number. In the simplest systems, players buy and sell contracts to pay 100 units of fake or real money at some future point - like the end of a game or an election.
      • Source: Predict the Future? You Can Bet on It
        [ http://www.nytimes.com/2003/10/02/technology/circuits/02mark.html ], Peter Wayner, NYTimes, 03/10/02

  4. A Study On Virtual Market Model For e-Marketplace Server, Elec. Comm. Res. & Appl. Bookmark and Share

    Abstract: Internet procurement is now in progress and is regarded as an information infrastructure for global business. As the number and diversity of EC (electronic commerce) participants grows at the agile environment, the complexity of purchasing from a vast and dynamic array of goods and services needs to be hidden from the end user. Putting the complexity into the EC system instead means providing flexible auction server for enabling commerce within different business units. In this paper, we propose an e-Marketplace server for B2B EC with multi-agent paradigm (...).
    • Source: A Study On Virtual Market Model For e-Marketplace Server
      [ http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6X4K-48TM2CG-1&_user=10&_handle=W-WA-A-A-AW-MsSAYVW-UUW-AUZCACDVWE-ADWDAVEV-AW-U&_fmt=summary&_coverDate=12%2F31%2F2003&_rdoc=10&_orig=browse&_srch=%23toc%237329%232003%23999979996%23450562!&_cdi=7329&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=33b602c9f8eed4cf9df3830227c9cc02 ], T. Kaihara - kaiharaacs.kobe-u.ac.jp, DOI: 10.1016/S1567-4223(03)00029-2, Autumn 2003
    • Contributed by Pritha Das - prithadas01ayahoo.com

  5. Universal Mechanisms in the Growth of Voluntary Organizations, arXiv Bookmark and Share

    Abstract: We analyze the growth statistics of Swedish trade unions and find a universal functional form for the probability distribution of growth rates of union size, and a power law dependence of the standard deviation of this distribution on the number of members of the union. We also find that the typical size and the typical number of local chapters scales as a power law of the union size. Intriguingly, our results are similar to results reported for other human organizations of a quite different nature. Our findings are consistent with the possibility that universal mechanisms may exist governing the growth patterns of human organizations.
    • Source: Universal Mechanisms in the Growth of Voluntary Organizations
      [ http://arXiv.org/abs/nlin.AO/0310001 ], Fredrik Liljeros, Luis A Nunes Amaral, H. Eugene Stanley, DOI: nlin.AO/0310001, arXiv, 2003-10-01

    1. Volunteering Leads To Rock-Paper-Scissors Dynamics In A Public Goods Game, Nature Bookmark and Share

      Excerpts: Collective efforts are a trademark of both insect and human societies. They are achieved through relatedness in the former and unknown mechanisms in the latter. (...) It can be maintained by the opportunity to punish defectors (...). Both schemes require that defectors are identified. Theorists propose that a simple but effective mechanism operates under full anonymity. (...) Here we show experimentally that volunteering generates these dynamics in public goods games and that manipulating initial conditions can produce each predicted direction. (...) On average, cooperation is perpetuated at a substantial level.
      • Source: Volunteering Leads To Rock–Paper–Scissors Dynamics In A Public Goods Game
        [ http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v425/n6956/full/nature01986_fs.html ], Dirk Semmann, Hans-Jürgen Krambeck, Manfred Milinski, DOI: 10.1038/nature01986, Nature 425, 390 - 393, 25 September 2003

  6. Are More People Cheating?, NYTimes Bookmark and Share

    Excerpts: (...) "by its nature cheating is intended to go undetected, and trends in unethical behavior can be hard to document." (...) student cheating, because studies have documented its rise in recent years. And there is broad agreement that the Internet has certainly made it much easier to plunder other people's work. Yet even in this area educators, ethicists and lawmakers warn that the Internet has created a murky territory of outdated laws and shifting standards. "Law, technology and ethics are not in sync right now,"(...).
    • Source: Are More People Cheating?
      [ http://www.nytimes.com/2003/10/04/arts/04CHEA.html ], Felicia R. Lee, NYTimes, 03/10/04

  7. Leading Takes More Than A Vision, Darwin Mag Bookmark and Share

    Excerpts: Leading An organization today has become more complex, requiring substantially more than stating a vision or articulating a strategy. In addition to being the facilitator between the inside and outside arenas associated with the corporation, the CEO and top management must juggle a variety of tasks to help their managers and employees become more effective in their jobs.
    • Source: Leading Takes More Than A Vision
      [ http://www.darwinmag.com/read/100103/vision.html ], Chuck Martin, Darwin Mag, 03/10

  8. Reducing Underage Drinking Requires Cooperative Effort, National Academies Bookmark and Share

    Excerpts: Reducing underage drinking requires a cooperative effort from all levels of government, alcohol manufacturers and retailers, the entertainment industry, parents and other adults in a community, says a new report from the National Academies' Institute of Medicine and National Research Council. The report proposes a comprehensive strategy to curb underage drinking, a problem that costs the nation an estimated $53 billion annually, due in part to losses stemming from traffic fatalities and violent crime.
    • Source: Reducing Underage Drinking Requires Cooperative Effort
      [ http://www4.nationalacademies.org/news.nsf/isbn/0309089352?OpenDocument ], Mary Ellen O'Connell et al., National Academies, 03/09/09

  9. Active Internet Traffic Filtering: Real-time Response to Denial of Service Attacks, arXiv Bookmark and Share

    Abstract: Denial of Service (DoS) attacks are one of the most challenging threats to Internet security. An attacker typically compromises a large number of vulnerable hosts and uses them to flood the victim's site with malicious traffic, clogging its tail circuit and interfering with normal traffic. At present, the network operator of a site under attack has no other resolution but to respond manually by inserting filters in the appropriate edge routers to drop attack traffic. However, as DoS attacks become increasingly sophisticated, manual filter propagation becomes unacceptably slow or even infeasible.
    In this paper, we present Active Internet Traffic Filtering, a new automatic filter propagation protocol. We argue that this system provides a guaranteed, significant level of protection against DoS attacks in exchange for a reasonable, bounded amount of router resources. We also argue that the proposed system cannot be abused by a malicious node to interfere with normal Internet operation. Finally, we argue that it retains its efficiency in the face of continued Internet growth.
    • Source: Active Internet Traffic Filtering: Real-time Response to Denial of Service Attacks
      [ http://arXiv.org/abs/cs.NI/0309054 ], Katerina J. Argyraki, David R. Cheriton, DOI: cs.NI/0309054, arXiv, 2003-09-29

    1. Confessions of a Spam King, NYTimes Bookmark and Share

      Excerpts: He likes to call it ''bulk e-mailing,'' for starters. And he considers it just one of the many exciting new markets available on the Internet. (...) tell you about some smart economic angle he has figured out, some new edge. (...) (...)good reason that so many spammers wind up on Spam Beach: ''Boca Raton is where they used to run those pump-and-dump investment scams and where the telemarketing sweatshops are.'' (...) pushed aside by the new boys on the block, the bulk e-mailers of the Internet.
      • Source: Confessions of a Spam King
        [ http://www.nytimes.com/2003/09/28/magazine/28SPAMLT.html ], Jack Hitt, NYTimes, 03/09/28

  10. How to Find That Needle Hopelessly Lost in the Haystack, NYTimes Bookmark and Share

    Excerpts: New product tags equipped with microchips and tiny antennas could one day make it easy to scan all the groceries in a bag simultaneously, allow businesses to locate any item in a warehouse instantly (...) . Hitachi announced this month that it has developed tags so small that they can be embedded in bank notes to foil money launderers and counterfeiters. Tags with the technology known as radio frequency identification, or R.F.I.D., transmit a digital response when contacted by radio signals from scanning devices.
    • Source: How to Find That Needle Hopelessly Lost in the Haystack
      [ http://www.nytimes.com/2003/09/29/technology/29TAGS.html ], Barnaby J. Feder, NYTimes, 03/09/29

  11. Biological Basis For Creativity Linked To Mental Illness, ScienceDaily Bookmark and Share

    Excerpts: Psychologists (...) have identified one of the biological bases of creativity. (...) brains of creative people appear to be more open to incoming stimuli from the surrounding environment. Other people's brains might shut out this same information through a process called "latent inhibition" - defined as an animal's unconscious capacity to ignore stimuli that experience has shown are irrelevant to its needs. "Scientists have wondered for a long time why madness and creativity seem linked. (...) low levels of latent inhibition and exceptional flexibility in thought might predispose to mental illness under some conditions and to creative accomplishment under others."
    • Source: Biological Basis For Creativity Linked To Mental Illness
      [ http://www.sciencedaily.com/releases/2003/10/031001061055.htm ], ScienceDaily & Univ. Of Toronto, 2003/10/01
    • Contributed by Atin Das - dasatinayahoo.co.in

    1. Long-Term Retention Of The Differential Values Of Arabic Numerals By Chimpanzees, Animal Cognition Bookmark and Share

      Abstract: (...) two chimpanzees used a joystick to collect dots, one-at-a-time, on a computer monitor, and then ended a trial when the number of dots collected was equal to the Arabic numeral presented for the trial. Here, the chimpanzees were presented with the task again after an interval of 6 months and then again after an additional interval of 3.25 years. (...) both chimpanzees performed above chance levels in collecting a quantity of dots equal to the target numeral, one chimpanzee for the numerals 1-7, and the second chimpanzee for the numerals 1-6.
      • Source: Long-Term Retention Of The Differential Values Of Arabic Numerals By Chimpanzees (Pan Troglodytes)
        [ http://www.springerlink.com/app/home/contribution.asp?wasp=320e3xxgtm0jylv5pn5u&referrer=parent&backto=issue,1,15;journal,1,21;browsepublicationsresults,24,491; ], I. Kurtzer - isaacabiomed.queensu.ca, p. dizio & j. lackner, DOI: 10.1007/s10071-003-0191-x, 2003/09/18
      • Contributed by Atin Das - dasatinayahoo.co.in

  12. Neuromaturation Of Human Locomotion Revealed By Non-Dimensional Scaling, Experi. Brain Res. Bookmark and Share

    Abstract: When two fundamental gait parameters-step length and step frequency-are scaled non-dimensionally, thereby accounting for increases in a child's physical size, ontogenetic changes in the locomotor control strategy are revealed. We believe dimensionless velocity, the product of dimensionless step length and frequency, serves as a measure of neural development. It increases from the age of 18 months and reaches a plateau between 50 and 90 months, attaining the adult value of 0.45. Based on a study of 200 children, our findings lend support to a theory that posits a neuromaturation growth curve (...).
    • Source: Neuromaturation Of Human Locomotion Revealed By Non-Dimensional Scaling
      [ http://www.springerlink.com/app/home/contribution.asp?wasp=3aa8lu4d757kqh8030vn&referrer=parent&backto=issue,22,84;journal,1,153;browsepublicationsresults,155,491; ], C. L. Vaughan - kvaughanacormack.uct.ac.za, n. g. langerak & m. j. o'malley, DOI: 10.1007/s00221-003-1635-x, 2003/09/12
    • Contributed by Atin Das - dasatinayahoo.co.in

  13. An Age of Instability, Science Bookmark and Share

    Excerpts: (...) yeast cell aging is accompanied by increased genetic instability, a hallmark of cancer. This finding might help researchers to understand the link between cancer and old age in humans. In the final decades of life, one's chance of developing cancer rises exponentially. (...) Certainly, cells isolated from the elderly have more chromosomal abnormalities than cells from the young. (...) rates of spontaneous mutation are too low to account for the extensive genome rearrangements found in tumors. Experiments in mice have confirmed the suspicion that mutation rates increase with age.
    • Source: An Age of Instability
      [ http://www.sciencemag.org/cgi/content/summary/301/5641/1859 ], David A. Sinclair, Science 2003 301: 1859-1860

    1. An Age-Induced Switch to a Hyper-Recombinational State, Science Bookmark and Share

      Abstract: There is a strong correlation between age and cancer, but the mechanism by which this phenomenon occurs is unclear. We chose Saccharomyces cerevisiae to examine one of the hallmarks of cancer-genomic instability- as a function of cellular age. As diploid yeast mother cells aged, an 100-fold increase in loss of heterozygosity (LOH) occurred. Extending life-span altered neither the onset nor the frequency of age-induced LOH; the switch to hyper-LOH appears to be on its own clock. In young cells, LOH occurs by reciprocal recombination, whereas LOH in old cells was nonreciprocal, occurring predominantly in the old mother's progeny. Thus, nuclear genomes may be inherently unstable with age.
      • Source: An Age-Induced Switch to a Hyper-Recombinational State
        [ http://www.sciencemag.org/cgi/content/abstract/301/5641/1908 ], Michael A. McMurray, Daniel E. Gottschling, Science 2003 301: 1908-1911.

  14. Now Hear This, Quickly, NYTimes Bookmark and Share

    Excerpts: The new software programs, DVD players and phone services rising to this challenge all take advantage of the human ability to comprehend speech much more quickly than the typical spoken rate of 140 to 180 words a minute. How many times as fast? "I've heard of instances where people go to 4X, and they still want it to go faster," (...). Scientists have long known that people can understand speech at a rate of up to 400 words a minute and beyond.
    • Source: Now Hear This, Quickly
      [ http://www.nytimes.com/2003/10/02/technology/circuits/02spee.html ], Douglas Heingartner, NYTimes, 03/10/02

  15. Applied Physics: Spintronics Gets A Magnetic Flute, Nature Bookmark and Share

    Excerpts: Magnetic-memory devices of the future could be based on 'spintronics', through switching the directions of electron spins. (...) Progress in understanding the microscopic behaviour of electrons continues to open up new frontiers for materials and device research, and vice versa. Watching how electrons move, at high current density, through structures that are less than 100 nm in size has revealed a wealth of new physics based on the 'spin' properties of these particles, and potentially a new class of electronic device: a spin-transfer switch for magnetic-memory 'spintronics'.
    • Source: Applied Physics: Spintronics Gets A Magnetic Flute
      [ http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v425/n6956/full/425359a_fs.html ], Jonathan Sun, DOI: 10.1038/425359a, Nature 425, 359 - 361, 25 September 2003

  16. Uniform Resonant Chaotic Mixing In Fluid Flows, Nature Bookmark and Share

    Excerpts: Laminar flows can produce particle trajectories that are chaotic, with nearby tracers separating exponentially in time. For time-periodic, two-dimensional flows and steady three-dimensional (3D) flows, enhancements in mixing due to chaotic advection are typically limited by impenetrable transport barriers that form at the boundaries between ordered and chaotic mixing regions. (...).The system is an oscillating horizontal vortex chain (...), occurring in many geophysical, industrial and biophysical flows. We observe completely uniform mixing, as predicted3-5 by singularity-induced diffusion, but only for oscillation periods close to typical circulation times.
    • Source: Uniform Resonant Chaotic Mixing In Fluid Flows
      [ http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v425/n6956/full/nature01993_fs.html ], T. H. Solomon, Igor Mezi, DOI: 10.1038/nature01993, Nature 425, 376 - 380, 25 September 2003

  17. Particle Formation by Ion Nucleation in the Upper Troposphere and Lower Stratosphere, Science Bookmark and Share

    Summary: Clouds and Cosmic Rays Particle nucleation in the upper troposphere and lower stratosphere is an important step in the chain of events that produces clouds, but the mechanisms that contribute to this process are poorly understood. One possible avenue of particle nucleation is by the ionization of gas phase particles by galactic cosmic rays, which can then act as seeds for droplets. Lee et al. (p. 1886) describe observations of new particle formation in the upper troposphere and lower stratosphere, and results from a numerical model, which together show that the abundance and size distribution of these particles are consistent with production by this type of ion-induced nucleation. Hence, galactic cosmic rays appear to affect the production of aerosol particles and, in turn, Earth's radiative energy balance and climate.
    • Source: Particle Formation by Ion Nucleation in the Upper Troposphere and Lower Stratosphere
      [ http://www.sciencemag.org/cgi/content/abstract/301/5641/1886 ], S.-H. Lee, J. M. Reeves, J. C. Wilson, D. E. Hunton, A. A. Viggiano, T. M. Miller, J. O. Ballenthin, L. R. Lait, Science Sep 26 2003: 1886-1889

  18. Interactions Between Ecological And Climatic Systems In Northern Africa, Ecosystems Bookmark and Share

    Abstract: The Sahara and Sahel regions of northern Africa have complex environmental histories punctuated by sudden and dramatic "regime shifts" in climate and ecological conditions. Here we review the current understanding of the causes and consequences of two environmental regime shifts in the Sahara and Sahel. (...) we conclude that the existence of alternative stable states (or regimes) in the climate and ecosystems of the Sahara and Sahel may be the result of strong, nonlinear interactions between vegetation and the atmosphere. Although the shifts between these regimes occur rapidly, they are made possible by slow, subtle changes in underlying environmental conditions (...).
    • Source: Regime Shifts In The Sahara And Sahel: Interactions Between Ecological And Climatic Systems In Northern Africa
      [ http://www.springerlink.com/app/home/contribution.asp?wasp=2l5x18d0fkcvtg593nr7&referrer=parent&backto=issue,4,14;journal,1,39;browsepublicationsresults,119,491; ], J. A. Foley - jfoleyawisc.edu, m. t. coe, m. scheffer & g. wang, DOI: 10.1007/s10021-002-0227-0, 2003/09/09
    • Contributed by Pritha Das - prithadas01ayahoo.com

  19. Complex Challenge: Terrorist Networks Bookmark and Share


    1. Government Seeks Next-Generation Biosensors, The Scientist Bookmark and Share

      Excerpts: (...)new agency plans to award upwards of $350 million in contracts (...). HSARPA is seeking proposals to develop, field test, and commercialize sensors capable of detecting a wide range of biological and chemical agents in the open air as well as inside buildings. The systems should operate continuously, be fully autonomous, and be able to identify and signal alerts for a minimum of 20 bioterror agents and "a large range" of toxic chemicals. The detectors must also be highly accurate, reliable, low maintenance, modest in size, and affordable.
      Editor's Note: This total research budget is comparable to the amount allocated so far for the search of WMD in Iraq.
      • Source: Government Seeks Next-Generation Biosensors
        [ http://www.biomedcentral.com/news/20030930/04 ], Ted Agres, The Scientist, 03/09/30

    2. U.S. Uses Terror Law to Pursue Crimes From Drugs to Swindling, NYTimes Bookmark and Share

      Excerpts: The Bush administration, which calls the USA Patriot Act perhaps its most essential tool in fighting terrorists, has begun using the law with increasing frequency in many criminal investigations that have little or no connection to terrorism. The government is using its expanded authority under the far-reaching law to investigate suspected drug traffickers, white-collar criminals, blackmailers, child pornographers, money launderers, spies and even corrupt foreign leaders, (...). Justice Department officials say they are simply using all the tools now available to them to pursue criminals - terrorists or otherwise.
      • Source: U.S. Uses Terror Law to Pursue Crimes From Drugs to Swindling
        [ http://www.nytimes.com/2003/09/28/politics/28LEGA.html ], Eric Lichtblau, NYTimes, 03/09/28

    3. Building Intelligence to Fight Terrorism, James Steinberg, Mary, Brookings Policy Brief Bookmark and Share

      Excerpts: Policymakers must go further to build a new intelligence system to support transformed national security needs. Threats involving unknown perpetrators, methods, and targets cannot be countered with strategies designed for use by federal officials to combat more predictable adversaries. Today, state and local law enforcement, public health, and emergency response personnel are on the front lines of detecting and responding to terrorist threats; corporate managers are responsible for securing key infrastructure such as energy supplies, chemical plants, and telecommunications; and workers and neighborhood residents may hold information that can help prevent attacks.
      • Source: Building Intelligence to Fight Terrorism, James Steinberg, Mary
        [ http://www.brookings.edu/comm/policybriefs/pb125.htm ], James B. Steinberg, Mary Graham, Andrew Eggers, Brookings Policy Brief #125, 03/09

  20. Links & Snippets Bookmark and Share


    1. Other Publications Bookmark and Share

      1. Ontological Uncertainty and Innovation, David A. Lane, Robert M. Maxfield, DOI: SFI-WP 03-09-050
      2. Threshold Behavior and Aggregate Fluctuation, Makoto Nirei, DOI: SFI-WP 03-09-049
      3. Local Evaluation Functions and Global Evaluation Functions for Computational Evolution, Jing Han, DOI: SFI-WP 03-09-048
      4. Art Out Of Body Movements, A new computer system aims to create visuals and sound scapes using the artist's body movements and a 3D canvas.
      5. ''The Grid gets real!'' @CERN Geneva - Tuesday Oct. 7th
      6. Huge Computing Power Goes Online, The first phase of an ambitious computing network designed to handle huge amounts of data is launched.
      7. New Transistor Created That Uses 80 Percent Less Power , An innovative chip design for future wireless devices has been created that can improve performance fourfold or reduce power consumption fivefold.
      8. Microbial Co-op in Evolution, Getting by with a little help from their friends
      9. Systems Biology Has its Backers and Attackers, Revolution or buzzword du jour, pundits ponder a pervasive term
      10. Putting the Buzz in Navigation, Scientists apply bee and dragonfly research to robotics, aviation, and the military
      11. Volcanic Blast Recorded In DNA, Tortoises living on the slopes of a Galapagos volcano have the signature of an ancient eruption written in their DNA, scientists say.
      12. Reprogramming Control of an Allosteric Signaling Switch Through Modular Recombination, John E. Dueber, Brian J. Yeh, Kayam Chak, Wendell A. Lim, Science Sep 26 2003: 1904-1908.
      13. Salmonella SipA Polymerizes Actin by Stapling Filaments with Nonglobular Protein Arms, Mirjana Lilic, Vitold E. Galkin, Albina Orlova, Margaret S. VanLoock, Edward H. Egelman, C. Erec Stebbins, Science Sep 26 2003: 1918-1921.
      14. 5 Technologies That Will Change the World, Scott Kirsner, 03/09, Fast Company, pg 93
      15. The Octopus as Eyewitness , Michelle Delio, 03/09/26, Wired
      16. Washington Insiders' New Firm Consults on Contracts in Iraq, Douglas Jehl, 03/09/30, NYTimes
      17. Schrödinger's Cat Comes Closer, Object big enough to see with microscope could be in two places at once. Philip Ball, 03/10/01, Nature Science update
      18. Pilots Practice How to Down Hijacked Jets, The U.S. military practices how to shoot down hijacked commercial airliners as often as three to four times a week, a senior general said on Thursday. Eric Schmitt, 03/10/03, NYTimes
      19. Government Lawyers Fear 9/11 Ruling Threatens Qaeda Cases, Philip Shenon, 03/10/04, NYTimes
      20. French-Made Missiles Turn Up in Iraq , Steven R. Hurst, 03/10/04, Guardian
      21. Sizing Up Nature's Denizens, From insects to Blue whales, various constraints dictate an organism's size, 03/10/06, The Scientist
      22. A Measure of Betweenness Centrality Based on Random Walks, M. E. J. Newman, 2003-09-01, arXiv, DOI: cond-mat/0309045
      23. A Quasispecies on a Moving Oasis, Michael M. Desai, David R. Nelson, 2003-09-26, arXiv, DOI: q-bio.PE/0309015
      24. Multidisciplinary Creativity: The Case of Herbert A. Simon, Subrata Dasgupta, 2003-09/10, Cognitive Science 27(5):683-707, DOI: 10.1016/S0364-0213(03)00063-6
      25. The Use Of Visual Feedback And On-Line Target Information In Catching And Grasping, T. Schenk - thomas.schenkadur.ac.uk, b. mair & j. zihl, 2003/09/12, DOI: 10.1007/s00221-003-1642-y
      26. Task-Dependent Motor Learning, I. Kurtzer - isaacabiomed.queensu.ca, p. dizio & j. lackner, 2003/09/16, DOI: 10.1007/s00221-003-1632-0
      27. Sound Recognition And Localization In Man: Specialized Cortical Networks And Effects Of Acute Circumscribed Lesions, M. Adriani, P. Maeder, R. Meuli, A. B. Thiran, R. Frischknecht, J. G. Villemure, J. Mayer, J. M. Annoni, J. Bogousslavsky, E. Fornari, J. P. Thiran & S. Clarke - stephanie.clarkeachuv.hospvd.ch, 2003/09/18, DOI: 10.1007/s00221-003-1616-0
      28. Study To Assess The Effects Of Mobile Phones On Hearing Nears End Of First Phase, S. Watts - s.a.wattsasoton.ac.uk, 2003/09/25
      29. Long-Term Moderate Elevation Of Corticosterone Facilitates Avian Food-Caching Behaviour And Enhances Spatial Memory, V. V. Pravosudov, 2003/09/29
      30. The Effect Of Foraging Parameters On The Probability That A Dive Is Successful, A. I. Houston, J. M. McNamara, J. E. Heron & Z. Barta, 2003/09/29
      31. Cloning Of An Olfactory Sensory Neuron-Specific Protein In The Land Snail (Eobania Vermiculata), A. Mazzatenta, P. Pelosi & A. Cellerino, 2003/09/29
      32. 'Good' Chemical, Neurons In Brain Elevated Among Exercise Addicts, 2003/09/29, ScienceDaily & Oregon Health & Sc. Univ.
      33. What Are The Chances? Mathematician Solves Evolutionary Mystery, 2003/09/29, ScienceDaily & Michigan Tech. Univ.
      34. Why Marriages, Voting And Traffic Can All Be Explained By Physics, D. Reid - david.reidaiop.org, 2003/09/30
      35. Johns Hopkins APL Creates System To Detect Digital Video Tampering, 2003/10/01, ScienceDaily & Johns Hopkins Univ.
      36. Summation Of Power Series By Self-Similar Factor Approximants, V. I. Yukalov - yukalovathsun1.jinr.ru, s. gluzman & d. sornette, 2003/10/15, DOI: 10.1016/S0378-4371(03)00549-1
      37. Phase Transition And 1/f Noise In A Computer Network Model, F. Liu - fliuatsinghua.org.cn, x. shan, y. ren & j. zhang, 2003/10/15, DOI: 10.1016/S0378-4371(03)00614-9
      38. Cosmologists Cluster To Plot Course Towards Dark Energy , Geoff Brumfiel, 25 September 2003, Nature 425, 335 , DOI: 10.1038/425335a
      39. Stem Cells: To Be And Not To Be , Haifan Lin - hlinaduke.edu, 25 September 2003, Nature 425, 353 - 355 , DOI: 10.1038/425353a
      40. Trust And e-Commerce: A Study Of Consumer Perceptions, B. J. Corbitt - bcorbittadeakin.edu.au, t. thanasankit & h. yi, Autumn 2003, DOI: 10.1016/S1567-4223(03)00024-3
      41. Dissolving A Partnership (Un)Fairly, J. Morgan, May 2004, DOI: 10.1007/s00199-003-0409-9
      42. Connective Tissue - Get Connected, V. Duance, Oct. 2003
      43. Homework: An Easy Load?, According to data analyzed by the Brookings Brown Center on Education Policy, the great majority of students at all grade levels now spend less than one hour studying on a typical day-an amount that has not changed substantially in at least twenty years. Falk Auditorium, Wednesday, October 1, 10:00am

    2. Webcast Announcements Bookmark and Share

      1. Fair Value; The Good, The Bad, and The Unknown, Financial Executives International (FEI), 03/08/26, 5:00-6:00 p.m. GMT
      2. 13th Ann Intl Conf, Soc f Chaos Theory in Psych & Life Sciences, Boston, MA, USA, 2003/08/08-10
      3. IMA International Conference Bifurcation 2003, Univ. Southampton, UK, 27-30 July, 2003
      4. New Santa Fe Institute President About His Vision for SFI's Future Role, (Video, Santa Fe, NM, 03/06/04)
      5. Edge Videos
      6. SPIE's 1st Intl Symp on Fluctuations and Noise, Santa Fe, NM, 2003/06/01-04
      7. NAS Sackler Colloquium on Mapping Knowledge Domains, Video/Audio Report, 03/05/11
      8. Uncertainty and Surprise: Questions on Working with the Unexpected and Unknowable, The University of Texas Austin, Texas USA, 2003/04/10-12
      9. New Trends In Industrial Partnership And Innovation Management At European Research Laboratories, CERN, Geneva, 2003/03/19 (with webcast)

        1. CERN Webcast Service, Streamed videos of Archived Lectures and Live Events

      10. Dean LeBaron's Archive of Daily Video Commentary, Ongoing Since February 1998
      11. ECAL 2003, 7th European Conference on Artificial Life, Dortmund, Germany, 03/09/14-17
      12. The Semantic Web and Language Technology - Its Potential and Practicalities, Bucharest, Romania, 03/07/28-08/08

    3. Conference & Call for Papers Announcements Bookmark and Share

      1. Executive Leadership in a Changing Environment, Washington, DC, 03/09/07-12, 03/10/05-10
      2. Exystence Thematic Institute - Algorithms And Challenges In Hard Combinatorial Problems, Turin, Italy, 03/10/01-30
      3. Intl School Mathematical Aspects of Quantum Chaos II Quantum Chaos on Hyperbolic Manifolds, Schloss Reisensburg (Gunzburg, Germany), 03/10/04-11
      4. European Workshop on The Analysis of Microfabrics in Geomaterials, Munchen, Germany, 03/10/06-11
      5. Plexusinstitute Organizational Management Conference With Ralph Stacey, Washington, DC, 03/12/02-04
      6. XVII Brazilian Symposium on Artificial Intelligence, Sao Luis, Maranhao - Brazil, 04/09/22-24
      7. Art & Artificial Life International Competition, [red]Deadline[/red]: 03/10/31
      8. Evolutionary Substrates of Communication, Signaling, and Perception in the Dynamics of Social Complexity, London, England, 03/10/08-10
      9. From Animals To Animats 8, 8th Intl Conf On The Simulation Of Adaptive Behavior (SAB'04), Los Angeles, USA, 04/07/13-17
      10. 13th International Symposium on HIV & Emerging Infectious Diseases, Toulon, France, 04/06/03-05
      11. 9th Annual Workshop on Economics and Heterogeneous Interaction Agents (WEHIA04),, Kyoto, Japan, 2004/05/27-29
      12. 3rd Intl Conf on Systems Thinking in Management (ICSTM 2004) "Transforming Organizations to Achieve Sustainable Success", Philadelphia, Pennsylvania, USA, 04/05/19-21
      13. Urban Vulnerability and Network Failure: Constructions and Experiences of Emergencies, Crises and Collapse, Manchester, UK, 04/04/29-30
      14. Fifth International Conference on Complex Systems (ICCS2004), Boston, MA, USA, 2004/05/16-21
      15. Fractal 2004, "Complexity and Fractals in Nature", 8th Intl Multidisciplinary Conf, Vancouver, Canada, 2004/04/04-07
      16. 4th Intl ICSC Symposium Engineering Of Intelligent Systems (EIS 2004), Island of Madeira, Portugal, 04/02/29-03/02
      17. 1st International Workshop on Biologically Inspired Approaches to Advanced Information Technology, Lausanne, Switzerland, 04/01/29-30
      18. 2nd Biennial Seminar on the Philosophical, Epistemological, and Methodological Implications of Complexity Theory, Havana, Cuba, 04/01/07-10
      19. 2003 IEEE/WIC Intl Joint Conf. Web Intelligence and Intelligent Agent Technology, Halifax, Canada, 2003/10/13-17

        1. Workshop on Collaboration Agents: Autonomous Agents for Collaborative Environments, Halifax, Canada, 03/10/13

      20. 2nd International Workshop on the Mathematics and Algorithms of Social Insects, Georgia Tech, Atlanta, Georgia, USA; 2003/12/15-17
      21. 3rd International Workshop on Meta-Synthesis and Complex System, Guangzhou, China, 2003/11/29-30
      22. 4th Intl Conf on Systems Science and Systems Engineering, Hong Kong, 03/11/25-28
      23. ICDM '03: The Third IEEE International Conference on Data Mining, Melbourne, Florida, USA, 2003/11/19-22
      24. American Society for Cybernetics (ASC) 2003 Conference (H.v.Foerster), Vienna, Austria, 2003/11/10-15
      25. Trends And Perspectives In Extensive And Non-Extensive Statistical Mechanics, In Honour Of The 60th Birthday Of Constantino Tsallis, Angra Dos Reis, Brazil, 2003/11/19-21
      26. Intl Congress on Computational Intelligence, Medellin, Colombia, 03/11/06-08,(Mirror)

    4. ComDig Announcement: New ComDig Archive in Beta Test Bookmark and Share

      We are in the process of upgrading the Complexity Digest archives to a format with improved search capabilities. Also, we will finally be able to adequately publish the valuable feedback and comments from our knowledgable readers. You are cordially invited to become a beta tester of our new ComDig2 archive.

    5. Special Announcement: Artists Explore Complex Systems, Federal Reserve Board Bookmark and Share

      COMPLEXITY, the first major museum exhibition about complex systems, is on display at the Federal Reserve Board in Washington, DC, ongoing - 03/11/28. The Washington exhibition is being co-sponsored by the Washington Center for Complexity and Public Policy and the Fine Arts Program of the Federal Reserve Board.