Complexity Digest 2001.07

12-Feb-2001

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Content

  1. Strong Radiative Heating Of Black Carbon In Atmospheric Aerosols, Nature
  2. The Universal Nature Of Biochemistry, PNAS
    1. Searching For An Alien Haven In The Heavens, PNAS
    2. State-Of-The-Art Instruments For Detecting Extraterrestrial Life, PNAS
    3. Possible Ecosystems And The Search For Life On Europa, PNAS
  3. Panel Seeks Truth in Lie Detector Debate, Science
  4. Fitness of Advanced Eusocial Bees, PNAS
  5. What You Don't Know Will Hurt You, Science
    1. Recolonizing Carnivores And Naive Prey, Science
    2. Learning Fast, New Scientist
  6. Tilling History With Biology's Tools, NYTimes
  7. McAfee Creates Global Map To Track Viruses, CNN
  8. Computer-Mad Generation Has A Memory Crash, Sunday Times
  9. Major Cause Of Global Warming -- Ordinary Soot, Science Daily
    1. Soot In The Greenhouse, Nature
  10. New Report Backs Planting More Trees to Fight Warming, NY Times
  11. The Great Seaweed Slaughter, Businessweek
  12. An Agility-Based OODA Model For The e-Commerce/e-Business Enterprise, War, Chaos, and Business
  13. Learning in the Pond Snail Lymnaea, Learn. Mem.
    1. Maze Navigation by Honeybees, Learn. Mem.
    2. Learning Motor Synergies, Learn. Mem.
  14. Crackling Noise, arXiv
  15. Nobel Laureate Herbert A. Simon Dies at Age 84, Carnegie Mellon News
  16. Links & Snippets
    1. Other Complexity Related Articles
    2. Pub Alert
    3. Announcements

  1. Strong Radiative Heating Of Black Carbon In Atmospheric Aerosols, Nature Next Article Bookmark and Share

    Aerosols affect the Earth's temperature and climate by altering the radiative properties of the atmosphere. A large positive component of this radiative forcing from aerosols is due to black carbon-soot-that is released from the burning of fossil fuel and biomass, and, to a lesser extent, natural fires, but the exact forcing is affected by how black carbon is mixed with other aerosol constituents. From studies of aerosol radiative forcing, it is known that black carbon can exist in one of several possible mixing states (…)


  2. The Universal Nature Of Biochemistry, PNAS Next Article Bookmark and Share

    Excerpt: People have long speculated about the possibility of life in settings other than Earth. Only in the past few centuries, however, have we been able to conceive of the specific nature of such settings: other planets around our own sun and solar systems similar to our own elsewhere in the physical universe. Speculation on the nature of life elsewhere often has paid little heed to constraints imposed by the nature of biochemistry, however. A century of fanciful science fiction has resulted not only in social enthusiasm for the quest for extraterrestrial life, but also in fanciful notions of the chemical and physical forms that life can take, what the nature of life can be. Since the time of the Viking missions to Mars, in the mid-1970s, our view of life's diversity on Earth has expanded significantly, and we have a better understanding of the extreme conditions that limit life. Consequently, our search for extant life elsewhere in the solar system can now be conducted with broader perspective than before. (...)


    1. Searching For An Alien Haven In The Heavens, PNAS Next Article Bookmark and Share

      Excerpt: The first few articles in this issue of PNAS constitute the beginning of a two-part Special Feature dedicated to the study of astrobiology. Astrobiology is not an autonomous or self-sustaining discipline. Rather, it is a hybrid subject emerging at the crossroads of astronomy, geology, paleontology, physics, and biology. What at first pass may seem like an amalgamation of disparate fields, upon further review, is a clear and increasingly defined discipline. The roots of astrobiology are found in the 10 distinct goals set by the National Aeronautics and Space Administration (NASA) Astrobiology Institute. These objectives can be summarized into three branches: How does life begin and develop? Does life exist elsewhere in the universe? What is life's future on Earth and beyond?


    2. State-Of-The-Art Instruments For Detecting Extraterrestrial Life, PNAS Next Article Bookmark and Share

      Excerpt: The Mars Organic Detector (MOD) is an instrument that has been developed to search for traces of the key organic compounds, amino acids/amines, and PAHs, directly on the Martian surface (19). MOD is based on the following concepts: (i) amino acids and PAHs can be directly sublimed from natural samples by heating to 450°C under partial vacuum, thus eliminating the use of the aqueous reagents and organic solvents used in laboratory analyses; (ii) sublimed amino acids condensed on a cold finger coated with a reagent specific for amino acids can be detected at very high sensitivities by using UV fluorescence; and (iii) sublimed PAHs can be directly detected on the cold finger because they are naturally fluorescent when exposed to UV light.


    3. Possible Ecosystems And The Search For Life On Europa, PNAS Next Article Bookmark and Share

      Excerpt: There is now great excitement over Jupiter's moon Europa as a possible location for extraterrestrial biology (9 http://www.pnas.org/cgi/content/full/98/3/801#B9 ). Here we examine Europa's suitability for life as we know it and consider candidate ecosystems that seem plausible in light of current knowledge. We then sketch life detection experiments that could be conducted with a spacecraft lander.

      (…) the gardening depth over 107 yr is 1 m, rather than 1-10 cm. In this case, oxidants and organics created by irradiation of Europa's surface can be efficiently buried by gardening, and therefore protected.


  3. Panel Seeks Truth in Lie Detector Debate, Science Next Article Bookmark and Share

    An expanded polygraph screening program at U.S. nuclear weapons labs begun in the wake of suspected espionage has heated up the perennial debate over the validity of lie detectors. And if testimony at the first meeting last week of a new National Academy of Sciences panel examining the thorny issue is any guide, the truth will be hard to come by. Researchers are, however, exploring alternate technologies, including the use of brain and thermal imaging, to identify what happens in the brain when people lie.

    Excerpt: First introduced in the 1920s, the polygraph machine measures four parameters--heart rate, blood pressure, respiration, and sweating. But that physiological quartet doesn't get at what Davidson says is presumably the emotion being measured, namely, "fear of detection." For that, he says, researchers must go straight to the brain: "And if there's one emotion that we have really learned a lot about in the last decade, it's fear."

    E.N.: As research on bio-feedback suggests, it is likely that professional spies will learn to control their fear signature in the brain.


  4. Fitness of Advanced Eusocial Bees, PNAS Next Article Bookmark and Share

    Abstract: Advanced eusociality sometimes is given credit for the ecological success of termites, ants, some wasps, and some bees. Comprehensive study of bees fossilized in Baltic amber has revealed an unsuspected middle Eocene (ca. 45 million years ago) diversity of eusocial bee lineages. Advanced eusociality arose once in the bees with significant post-Eocene losses in diversity, leaving today only two advanced eusocial tribes comprising less than 2% of the total bee diversity, a trend analogous to that of hominid evolution. This pattern of changing diversity contradicts notions concerning the role of eusociality for evolutionary success in insects.


  5. What You Don't Know Will Hurt You, Science Next Article Bookmark and Share

    When a predator enters a landscape and encounters prey that have no previous experience of that predator, the prey can suffer heavily. Berger et al. (p. 1036; see the Perspective by Gittleman and Gompper), in a study of wolves and bears preying on moose in North America and Scandinavia, show that most of the damage is inflicted along the front of the advancing predator population. However, naive prey quickly become accustomed to the new predators and change their behavior to avoid them. These findings bear on current human reintroductions of predators and on how fauna may have responded to advancing human populations during the Pleistocene.

    Excerpt: "Ecological circumstances, such as living on an island or in a pristine habitat, often lead to an unusually high level of predation among prey populations when predators are reintroduced. For example, Darwin was able to collect a specimen of the now extinct Falkland Island wolf simply by walking up to one and killing it. Indeed, 81% of known mammalian extinctions during the last 500 years have been among mammals endemic to island habitats."


    1. Recolonizing Carnivores And Naive Prey, Science Next Article Bookmark and Share

      Abstract: The current extinction of many of Earth's large terrestrial carnivores has left some extant prey species lacking knowledge about contemporary predators, a situation roughly parallel to that 10,000 to 50,000 years ago, when naïve animals first encountered colonizing human hunters. Along present-day carnivore recolonization fronts, brown (also called grizzly) bears killed predator-naïve adult moose at disproportionately high rates in Scandinavia, and moose mothers who lost juveniles to recolonizing wolves in North America's Yellowstone region developed hypersensitivity to wolf howls. Although prey that had been unfamiliar with dangerous predators for as few as 50 to 130 years were highly vulnerable to initial encounters, behavioral adjustments to reduce predation transpired within a single generation. The fact that at least one prey species quickly learns to be wary of restored carnivores should negate fears about localized prey extinction.


    2. Learning Fast, New Scientist Next Article Bookmark and Share

      Excerpt: Moose living in areas without any natural predators are easy targets when bears and wolves are reintroduced, but they wise up quickly, says a US team.

      Within one generation, the predation rate drops to the level found in areas where the animals have long co-existed. This has important implications for programmes to reintroduce predators, says Joel Berger of the University of Nevada.


  6. Tilling History With Biology's Tools, NYTimes Next Article Bookmark and Share

    Excerpt: Evolutionary biology has become the scholarly equivalent of Starbucks or the Gap. Neo- Darwinist explanations for everything from artistic creativity to morality and rape spill off the presses. Every academic department, it seems, has its biology-enamored theorist. Every department, that is, except history.

    Until recently, historians were virtually the only remaining holdouts in an otherwise successful conquest of American universities by the science of innate traits, adaptive strategies and biological imperatives.


  7. McAfee Creates Global Map To Track Viruses, CNN Next Article Bookmark and Share

    Excerpt: The map claims to allow users to view global virus trends, anticipate virus outbreaks and alert computer users to any virus epidemic.

    The data for the map is compiled from McAfee.com's Internet-based virus scanning service, which tracks thousands of computers worldwide for virus activity. Any incidences of virus infection are added to the global virus map in real time. The map contains information about the types of viruses that have affected each region, and the number of computers infected.


  8. Computer-Mad Generation Has A Memory Crash, Sunday Times Next Article Bookmark and Share

    Excerpt: Doctors are blaming computer technology, electronic organisers and automatic car navigation systems. They claim these gadgets lead to diminished use of the brain to work out problems and inflict "information overload" that makes it difficult to distinguish between important and unimportant facts.

    A preliminary study of 150 people aged 20 to 35 has shown that more than one in 10 are suffering from severe problems with their memory. Researchers from Hokkaido University's school of medicine in Japan said the memory dysfunction among the young required further investigation.


  9. Major Cause Of Global Warming -- Ordinary Soot, Science Daily Next Article Bookmark and Share

    Excerpt: In their frantic search for a solution to the global warming crisis, climatologists and policy makers have managed to overlook one of the leading causes of rising world temperatures - soot, the familiar black residue that coats fireplaces and darkens truck exhaust.

    According to a new study in the journal Nature, soot may be the second biggest contributor to global warming - just behind the infamous greenhouse gas, carbon dioxide (CO2).

    ``Soot - or black carbon - may be responsible for 15 to 30 percent of global warming, yet it`s not even considered in any of the discussions about controlling climate change,`` says Stanford Professor Mark Z. Jacobson, author of the Feb. 8 Nature study.

    Human beings produce most of the soot particles that pollute the atmosphere, observes Jacobson, an assistant professor of civil and environmental engineering.

    ``Soot consists primarily of elemental carbon,`` he says, ``and 90 percent of it comes from the consumption of fossil fuels - particularly diesel fuel, coal, jet fuel, natural gas and kerosene - as well as the burning of wood and other biomass when land is cleared.``

    A reduction in worldwide soot emissions, he maintains, could prove beneficial in slowing down the disastrous pace of global warming.


    1. Soot In The Greenhouse, Nature Next Article Bookmark and Share

      Excerpt: Greenhouse gases warm the planet by reflecting heat back to earth, while aerosols keep it cool by bouncing radiation back into space. This balance is already being upset by anthropogenic greenhouse gas emissions, and now Mark Jacobson argues in this week's issue that we are compounding the problem with emissions of black carbon (soot). Black carbon reduces the reflectivity of aerosols and as such may be the second most potent agent of global warming after carbon dioxide.


  10. New Report Backs Planting More Trees to Fight Warming, NY Times Next Article Bookmark and Share

    Excerpt: (…) countries could blunt warming by sopping up 10 to 20 percent of the heat-trapping carbon dioxide that is expected to be released by smokestacks and tailpipes over the next 50 years.

    It also says the cost to industrialized countries of a global climate plan could be cut in half if they were allowed to buy and sell credits earned by those that make the deepest reductions in carbon dioxide and other so-called greenhouse gases.


  11. The Great Seaweed Slaughter, Businessweek Next Article Bookmark and Share

    Excerpt: In Japan, a wasteful public-works project may be backfiring and damaging this year's crop. If so, it will be one more reason to end the boondoggles. (…)

    The plan was to have a network of dikes that would control flooding and create more farmland. But with the tidal flows of the entire area having been altered in a damaging way, it seems to have backfired. Ecologists have noticed an abnormal amount of phytoplankton, microscopic ocean-dwelling plants that thrive on sun, water, and nutrients -- the same nutrients seaweed needs to thrive. That is leading to a seaweed scarcity.

    Editor's note: Dried Seaweed (nori) is a significant ingredient of Japanese cuisine


  12. An Agility-Based OODA Model For The e-Commerce/e-Business Enterprise, War, Chaos, and Business Next Article Bookmark and Share

    Excerpt: Since the mid-1970's, there has been a subtle yet increasing awareness that the dominant business model of the 20th century, based upon limited product variability and mass production manufacturing techniques, no longer is applicable to the rapidly-fragmenting, information-intensive, electronically wired and individually-customized global marketplace which has emerged. The pervasiveness and universality of this awareness has been accelerated in the past few years with the explosive growth and penetration of the Internet and its diversity of e-Commerce/e-Business implementations.

    Post-mass production models to address the new commerce of "controlled chaos" are currently in a state of evolutionary refinement. However, there is widespread agreement that their principal characteristic must be AGILITY, that is, the ability to adapt to, or to lead, constant, accelerated, uncertain and unpredictable change.


  13. Learning in the Pond Snail Lymnaea, Learn. Mem. Next Article Bookmark and Share

    Abstract: We show that appetitive and aversive conditioning can be analyzed at the cellular level in the well-described neural circuitries underlying rhythmic feeding and respiration in the pond snail, Lymnaea stagnalis. To relate electrical changes directly to behavior, the snails were first trained and the neural changes recorded at multiple sites in reduced preparations made from the same animals. Changes in neural activity following conditioning could be recorded at the level of motoneurons, central pattern generator interneurons and modulatory neurons. Of significant interest was recent work showing that neural correlates of long-term memory could be recorded in the feeding network following single-trial appetitive chemical conditioning. Available information on the synaptic connectivity and transmitter content of identified neurons within the Lymnaea circuits will allow further work on the synaptic and molecular mechanisms of learning and memory.


    1. Maze Navigation by Honeybees, Learn. Mem. Next Article Bookmark and Share

      Abstract: We investigated the ability of honeybees to learn mazes of four types: constant-turn mazes, in which the appropriate turn is always in the same direction in each decision chamber; zig-zag mazes, in which the appropriate turn is alternately left and right in successive decision chambers; irregular mazes, in which there is no readily apparent pattern to the turns; and variable irregular mazes, in which the bees were trained to learn several irregular mazes simultaneously. The bees were able to learn to navigate all four types of maze. Performance was best in the constant-turn mazes, somewhat poorer in the zig-zag mazes, poorer still in the irregular mazes, and poorest in the variable irregular mazes. These results demonstrate that bees do not navigate such mazes simply by memorizing the entire sequence of appropriate turns. Rather, performance in the various configurations depends on the existence of regularity in the structure of the maze and on the ease with which this regularity is recognized and learned.


    2. Learning Motor Synergies, Learn. Mem. Next Article Bookmark and Share

      Abstract: Prism adaptation, a form of procedural learning, requires the integration of visual and motor information for its proper acquisition. Although the role of the visual feedback has begun to be understood, the nature of the motor information necessary for the development of the adaptation remains unknown. In this work we have tested the idea that modifying the arm load at different stages of the adaptation process, and the ensuing change of motor information perceived by the subjects, would modify the final properties of the adaptation. We trained a set of subjects to throw balls to a target while wearing prism glasses and varied the weight of their arms at different time points during the task. We observed that the acquisition of the adaptation was not affected by the change in load. However, its persistence (i.e., the aftereffect) was reduced when tested under a weight condition different from the training trials. Furthermore, when the training weight conditions were restored later during testing, a second, late aftereffect was unmasked, suggesting that the missing aftereffect did not disappear but had remained latent. Our results show that the internal representation of a motor memory incorporates information about load conditions and that the memory stored under a specific weight condition can be fully retrieved only when the original training condition is restored.


  14. Crackling Noise, arXiv Next Article Bookmark and Share

    Abstract: Crackling noise arises when a system responds to changing external conditions through discrete, impulsive events spanning a broad range of sizes. A wide variety of physical systems exhibiting crackling noise have been studied, from earthquakes on faults to paper crumpling. Because these systems exhibit regular behavior over many decades of sizes, their behavior is likely independent of microscopic and macroscopic details, and progress can be made by the use of very simple models. The fact that simple models and real systems can share the same behavior on a wide range of scales is called universality. We illustrate these ideas using results for our model of crackling noise in magnets, explaining the use of the renormalization group and scaling collapses. This field is still developing: we describe a number of continuing challenges.

    • Crackling Noise, James P. Sethna, Karin A. Dahmen, Christopher R. Myers, arXiv, cond-mat/0102091, 01/02/06

  15. Nobel Laureate Herbert A. Simon Dies at Age 84, Carnegie Mellon News Next Article Bookmark and Share

    Excerpt: Carnegie Mellon University Professor Herbert A. Simon, winner of the 1978 Nobel Prize in Economics and many prestigious international scientific awards for his work in cognitive psychology and computer science, died today (Feb. 9) at the age of 84. (…)

    His research ranged from computer science to psychology, administration and economics. The thread of continuity through all of his work was his interest in human decision-making and problem-solving processes and the implications of these processes for social institutions.

    He made extensive use of the computer as a tool for both simulating human thinking and augmenting it with artificial intelligence. Simon was widely considered to be a founder of the field of artificial intelligence. (..)

    This past fall, Carnegie Mellon honored Simon by naming its new computer science facility after him and the late Computer Science Professor Allen Newell. Both were recognized as founders of the fields of artificial intelligence and cognitive psychology. At a symposium in his honor, Simon commented extensively on the role of computing in the future. A full text of his remarks can be found at: http://www.ulib.org


  16. Links & Snippets Next Article Bookmark and Share

    1. Other Complexity Related Articles Next Article Bookmark and Share


    2. Pub Alert Next Article Bookmark and Share

      These references can be found in http://www.thescientificworld.com/. To retrieve the articles connect to the site and search for the title.

      • Lowering The Drawbridge Of The Fortress: Moving From Simplicity To Complexity, Norman, T.; Campbell, E., ORGANISATIONS AND PEOPLE
      • Intercultural Education And Complex Instruction. Some Remarks And Questions From An Anthropological Perspective On Learning, Verlot, M.; Pinxten, R., INTERCULTURAL EDUCATION
      • School Policy In Sweden-A School Case: A Complex Instruction Introductory Workshop, Brettell, L., INTERCULTURAL EDUCATION
      • Complex Instruction As A Tool For Developing The Role Of The Teacher. A workshop presented at the "Intercultural Education and Co-operative Learning" conference in Ghent, May 2000, Kujansivu, A.; Rosell, J.-A., Intercultural Education
      • Using Complex Instruction In Poland: The Case Of The Lauder-Morasha School, Koszynska, M., Intercultural Education
      • The Big Myth: An Intercultural Complex Instruction Unit On The Internet, Batelaan, P.; Passantino, F., Intercultural Education
      • Management Of Complex Cardiovascular Problems: The Consultant's Approach, Borau, F. A., Revista Espanola De Cardiologia
      • On Lower Bounds for the Communication Complexity of Private Information Retrieval, Itoh, T., Ieice Transactions On Fundamentals Of Electronics Communications And Computer Sciences E Series A
      • Resolution-Based Complexity Control for Gaussian Mixture Models, Meinicke, P.; Ritter, H., Neural Computation
      • Characteristics of Seismicity Evolution Revealed by Algorithmic Complexity, Yuejun, L.; Yuanzhong, L.; Yuejun, Z., Earthquake
      • Earthquake Complexity Precursor and a Nomaly of Multi-Fractal Spectrum of Strong Earthquakes, Lingren, Z.; Shiyong, Z.; Maling, Y.; Haitao, W.; Yan, Z., EARTHQUAKE
      • Institutional Arrangements For The Governance Of Complex Marine Resource Systems: Lessons From Wider Caribbean Marine Protected Areas, Mascia, M. B., Coastal Zone
      • Study On Genetic Mechanism Of Seismic Precursory Complexity (-), Mingruo, J.; Guomin, Z., Earthquake
      • Improving Realism Of A Surgery Simulator: Linear Anisotropic Elasticity, Complex Interactions And Force Extrapolation, Picinbono, G.; Lombardo, J.-C.; Delingette, H.; Ayache, N., Rapport De Recherche- Institut National De Recherche En Informatique Et En Automatique
      • Rapid Optimization And Minimal Complexity In Computational Neural Network Multivariate Calibration Of Chlorinated Hydrocarbons Using Raman Spectroscopy, Egan, W. J.; Angel, S. M.; Morgan, S. L., Journal Of Chemometrics
      • Simple Versus Cooperative Relaxations In Complex Correlated Systems, Mano, J. F.; Lanceros-Mendez, S., Journal Of Applied Physics
      • Developmental Changes In The Complexity Of The Electrocortical Activity In Foetal Sheep, Schmidt, K.; Kott, M.; Muller, T.; Schubert, H.; Schwab, M., Journal Of Physiology -Paris-
      • The Complexity of Linkage Analysis with Neural Networks, Marinov, M.; Weeks, D. E., Human Heredity
      • Attribute Grammars And Automatic Complexity Analysis, Mishna, M., Rapport De Recherche- Institut National De Recherche En Informatique Et En Automatique
      • Two-Dimensional Fluorometry Coupled With Artificial Neural Networks: A Novel Method For On-Line Monitoring Of Complex Biological Processes, Wolf, G.; Almeida, J. S.; Pinheiro, C.; Correia, V.; Rodrigues, C.; Reis, M. A. M.; Crespo, J. G., Biotechnology And Bioengineering
      • Variable Effect Of A Large Suspension-Feeding Bivalve On Infauna: Experimenting In A Complex System, Cummings, V. J.; Thrush, S. F.; Hewitt, J. E.; Funnell, G. A., Marine Ecology- Progress Series
      • Women's Untold Stories: Breaking Silence, Talking Back, Voicing Complexity, edited by Mary Romero and Abigail J. Stewart, Webster, S. K., PSYCHOLOGY OF WOMEN QUARTERLY
      • The Model Customer As Web Site Complexity Grows Exponentially, Customer Analysis, Which Involves Extracting Information From Web Server Logs And Integrating It With Other Data, Becomes More Difficult. A Data Collection Framework Can Provide The Proper Context To Make This Process Work, Richebacher, T. F., INTELLIGENT ENTERPRISE -SAN MATEO-
      • Handling complex boundaries on a Cartesian grid using surface singularities, Revstedt, J.; Fuchs, L., INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS
      • Complex Hypothesis Tracking of Moving Objects, Shirokov, L. E., JOURNAL OF COMPUTER AND SYSTEMS SCIENCES INTERNATIONAL C/C OF TEKHNICHESKAIA KIBERNETIKA
      • Bilaterally synchronous complex spike Purkinje cell activity in the mammalian cerebellum, Yamamoto, T.; Fukuda, M.; Llinas, R., EUROPEAN JOURNAL OF NEUROSCIENCE
      • Anticipation Model for Sequential Learning of Complex Sequences, Wang, D., LECTURE NOTES IN COMPUTER SCIENCE
      • Unified Analysis of Complex Nonlinear Motions via Densities, Yim, S. C. S.; Lin, H., NONLINEAR DYNAMICS

    3. Announcements Bookmark and Share


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