Complexity Digest 2001.19

07-May-2001

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Content

  1. Apoptosis, HMS Beagle
    1. APOPTOSIS: Death Of A Monopoly?, Science
  2. Proteins Are Vastly More Complicated Than Previously Realized, Science Daily
  3. Researchers Unfold Single RNA Molecules Using Mechanical Force, Science Daily
  4. A New Solution To The 3-Body Problem, Notices of the AMS
    1. Here Be No Dragons, Nature
  5. Microscopic Parasite Limits Own Virulence To Keep Host Alive, San Francisco Chronicle
    1. Regulation Of Differentiation To The Infective Stage Of Protozoan Parasite, Science
  6. Consistent Patterns And The Idiosyncratic Effects Of Biodiversity In Marine Ecosystems, Nature
  7. Sleep In Early Life May Play Crucial Role In Brain Development, Science Daily
  8. Mirror Self-Recognition In The Bottlenose Dolphin: A Case Of Cognitive Convergence, PNAS
    1. Brainy Dolphins Pass the Human 'Mirror' Test, NYTimes
  9. A Neural Correlate Of Syntactic Encoding During Speech Production, PNAS
  10. Computational Modeling Of Visual Attention Laurent, Nature
  11. Cortical Deafness To Dissonance, Brain
  12. Sex Matters, National Academy Of Sciences/Institute Of Medicine
  13. Prostate Cancer Complexity, Tracking The Disease's Genetic Roots Presents Enormous Challenges, The Scientist
  14. Glial Cells And The Synapse, Science
    1. Unwrapping Glial Cells From The Synapse: What Lies Inside?, Science
    2. Control Of Glutamate Clearance And Synaptic Efficacy By Glial Coverage Of Neurons, Science
    3. Glia-Synapse Interaction Through Ca2+-Permeable AMPA Receptors In Bergmann Glia, Science
  15. Integrated Genomic And Proteomic Analyses Of A Systematically Perturbed Metabolic Network, Science
  16. Circadian Rhythms In Plants, Annu. Rev. Plant Physiol. Plant Mol. Biol
  17. Complex Manoeuvres, Financial Times
    1. Winning The War On Complexity, Oracle White Paper
    2. Complex or Simple? Four Ways to Tell If You're Really an E-Business, Oracle.com
  18. Mutation, Selection, And Vertical Transmission Of Theistic Memes In Religious Canons, J. Memetics
  19. Is Suicide Contagious?, J. Memetics
  20. Links & Snippets
    1. Recent Santa Fe Institute Working Papers
    2. TheScientificWorld Pub Alert: "Complexity"
    3. Announcements

  1. Apoptosis, HMS Beagle Next Article Bookmark and Share

    Excerpts: Apoptosis [programmed "suicide" of cells, Ed.] plays a role in everything from early development to aging, as well as in a host of disease states. (…) one of the hottest topics in biology.

    Once the DNA has been cut, the cell sends signals to attract nearby immune cells, which consume the dead cell. Apoptosis prevents harmful contents of the dying cell from leaking out and hurting surrounding cells - unlike necrotic death, which leads to inflammation and can trigger apoptosis in previously healthy neighboring cells.

    • Apoptosis, Maia Szalavitz, HMS Beagle, Issue 101, 01/04/27


    1. APOPTOSIS: Death Of A Monopoly?, Science Next Article Bookmark and Share

      Excerpts: We know that a group of cysteine proteases named caspases are central to the death machinery inherited by all cells. Caspases act as the final executioners in a stereotyped cascade of molecular events leading ultimately to the cells' demise. (…) physiological evidence for an alternative mechanism by which cells can undergo apoptosis. (…) apoptosis-inducing factor (AIF) can induce PCD [Programmed Cell Death = Apoptosis, Ed.] in mammalian cells in a caspase-independent manner, and that this apoptotic pathway is strictly required for early development in the mouse.


  2. Proteins Are Vastly More Complicated Than Previously Realized, Science Daily Next Article Bookmark and Share

    Excerpts: The function of proteins - the workhorses of our bodies - depends on how those proteins are physically folded. Researchers around the world are examining the countless complex structures of proteins to learn more about therapies for the human body. Protein folding has been compared in complexity to the folding of delicate origami.

    This folding process is more complicated than previously realized, according to University of Washington researchers. Imagine trying to fold a delicate origami crane from silk paper - while you're in a wind tunnel. In fact, imagine trying to fold the origami in a wind tunnel while countless other hands are also pulling at the paper. And yet, that's comparable in complexity to what the hundreds of thousands of cells and proteins are doing in your body right now. (…)

    Vogel and colleagues ask these questions: What does force do to the fiber? How is force transmitted from the fiber to the cell? And how is force used to determine how the cell regulates the expression of certain proteins? "We are very excited about this because we believe a new field is being born: non-equilibrium protein structure-function analysis. It's very exciting to think about how nature regulates and controls function. We went from viewing the cell as a bag full of proteins a decade ago to a view of the cell as a dynamic place where proteins assemble and change under mechanical forces," Vogel says. (…)

    "Computer simulations allow us to see what happens to the structure if the protein ruptures," Vogel says. The computer simulations were done in collaboration with Dr. Klaus Schulten at the Beckman Institute in Illinois and former UW graduate student Andre Krammer. "People tend to think of protein function as biochemical - chemicals binding to the protein, for example. Only recently have people realized that mechanical tension - cells pulling on the matrix - is important," says David Craig, a graduate bioengineering student and another of the paper's authors.

    Vogel's lab is examining how mechanical force must be considered in the field of proteomics. "In proteomics, you go from the genome, then to the protein structure, and from that, make a prediction about the protein's function. But is that enough? Is it sufficient to only know the function in the equilibrium state?," Vogel says. "We think there are a series of proteins that may have different structures, depending on how much force is applied and how it is applied. If that is so, then it adds additional dimension to the field of proteomics."


  3. Researchers Unfold Single RNA Molecules Using Mechanical Force, Science Daily Next Article Bookmark and Share

    Excerpts: By applying precise, mechanical forces to the ends of individual RNA molecules, researchers have successfully unfolded and refolded the molecules. According to the scientists, measurements of the forces needed to unfold and refold these molecules will yield new information about how RNA molecules achieve their stable three-dimensional structures. (…)

    To measure the force needed to unfold a single RNA molecule, Bustamante and his colleagues attached each end of a test molecule to a single microscopic plastic bead via RNA/DNA "handles." They used an "optical trap" consisting of a laser beam that held and measured the force on one bead, as a piezoelectric actuator attached to the other bead supplied the minute forces required to unfold the molecule. The scientists also used the technique to measure the change in the length of the molecule as it was unfolded.

    "This system eliminated both the problems of averaging large numbers of molecules and the multiple reaction pathways," said Bustamante, "because when we are pulling, we are following a single molecule unfolding along a particular pathway."

    In their experiments, the scientists unfolded three kinds of RNA molecules, each more complex than the previous one:

    • the simplest, a folded "hairpin" RNA structure
    • an RNA that also contained a more complicated "helix junction" found in many folded RNAs
    • the most complex, an RNA that had a "bulge" in its structure, and can attain tertiary structure

    "Originally, we wanted to study a full ribozyme," said Bustamante, "but it became clear to us that the complexity we were observing when we pulled the ribozyme was going to make it impossible to understand everything from the beginning. Ultimately, we realized that because RNA molecules are hierarchical in their structure, with each domain being relatively independent, it would be possible to synthesize the different domains of the molecule and then pull on each type of domain to understand their characteristics."

    The results of the scientists' experiments revealed that each of the three types of RNA molecules had distinctive characteristics. For example, the hairpin and helix junction RNAs both exhibited a phenomenon the scientists called "hopping." In these instances, if the molecules were held at a constant force that was great enough to cause the molecule to transition to the unfolded state, they would hop back and forth between the unfolded and folded states. From that hopping state, the scientists could pinpoint the forces required to unfold the molecules, measure the rates of folding and unfolding and the energy of the process.

    They also found that the unfolding forces coincided with the refolding forces. "This means that all the work that we are doing mechanically, to pull the molecule, to unfold the molecule, is going to just break the bonds in the molecule that maintain the folding," said Bustamante. "This means you can carry the process at equilibrium."


  4. A New Solution To The 3-Body Problem, Notices of the AMS Next Article Bookmark and Share

    Background: Nonlinear dynamics arose out of Poincare's work on the celestial N-body problem. Given N celestial bodies and their initial positions and velocities, one seeks to determine their motion for all past time and all future time. To do this, one must solve N coupled second order ordinary differential equations. Henri Poincare showed that this essentially cannot be done if N is larger than two. (Isaac Newton had solved the 2-body problem, and a solution was sought for the N-body problem.) Not enough constants of motion exist to do this, so one can obtain chaotic dynamics. In his studies, Poincare became the first person to observe homoclinic tangles, which Stephen Smale later showed lead to his famous horseshoe chaos. Other notions of Hamiltonian dynamics,such as KAM theory and Arnold diffusion, also show up in the N-body problem. Celestial mechanics has played an essential role in the development of dynamical systems theory, and one cannot appreciate the evolution of the notion of chaos without some knowledge of the history and some of the intricacies associated with the celestial N-body problem.

    Excerpt: We describe a new solution to the three-body problem and motivate its discovery. We also sketch its existence proof, which is based on the direct method of the calculus of variations. We begin with the statement of the N-body problem and some of its solutions.

    Newton told us that two masses attract each other, the force of attraction being directed along the line joining them, proportional to the product of the masses, and inversely proportional to the square of the distance between them. (...)


    1. Here Be No Dragons, Nature Next Article Bookmark and Share

      Excerpts: Nature presents us with a bewildering variety of complex systems, from the Earth's atmosphere, to the stock market, to the anatomy of the fly. Their complexity appears in different ways and for different reasons. (…)

      Animals with six limbs would be interesting because they could adapt two limbs for manipulative purposes (centaurs) or for flying (dragons). But as centaurs and dragons do not exist, it is tempting to say that they must have had negligible probability of coming into being,


  5. Microscopic Parasite Limits Own Virulence To Keep Host Alive, San Francisco Chronicle Next Article Bookmark and Share

    Excerpt: (...) For decades, evolutionary biologists speculated that if a species of pathogen is to survive, it should wreak only so much infectious havoc, and no more. It is "a classic problem" of evolution, said famed evolutionary biologist Stephen Jay Gould of Harvard University. "You wonder, `Why would anything limit its own capacity to do what it's doing?' " Gould said. "And the obvious Darwinian answer is: If it kills its host, it (ultimately) kills itself - and that's not to its advantage.

    1. Regulation Of Differentiation To The Infective Stage Of Protozoan Parasite, Science Next Article Bookmark and Share

      Excerpt: (...) During its infectious cycle, the human pathogenic protozoan Leishmania spp. alternates between flagellated promastigote forms, which grow within the alimentary tract of the sand fly vector, and aflagellate amastigotes, which replicate within acidified phagolysosomes of vertebrate host macrophages. A critical step is metacyclogenesis, the differentiation of the noninfective procyclic promastigote to the highly infective metacyclic form within the sand fly (1). Several genes showing metacyclic-specific expression have been identified (2); however, the molecular mechanism(s) underlying the initiation and control of this vital step remain undefined. (...)


  6. Consistent Patterns And The Idiosyncratic Effects Of Biodiversity In Marine Ecosystems, Nature Next Article Bookmark and Share

    Excerpts: Revealing the consequences of species extinctions for ecosystem function has been a chief research goal (…).

    Diversity can influence aspects of ecosystem function, but questions remain as to how generic the patterns observed are, (…). Here we demonstrate variable diversity effects for species representative of marine coastal systems at both global and regional scales. We provide evidence for an increase in complementary resource use as diversity increases and show strong evidence for diversity effects in naturally assembled communities at a regional scale.


  7. Sleep In Early Life May Play Crucial Role In Brain Development, Science Daily Next Article Bookmark and Share

    Excerpts: The capacity for "change," or growth and strengthening, of connections between nerve cells is the basis of development in the brain. The elaboration and refinement of neural circuitry continues to a lesser extent in the adult brain. The process of growth, known as plasticity, is believed to underlie the brain's capacity to control behavior, including learning and memory. Plasticity occurs when neurons are stimulated by events, or information, from the environment. (…)

    "This is the first direct evidence that sleep modifies the effect of environmental stimuli on the development of new brain connections," says Frank.

    While the study focused specifically on the impact of sleep on neuronal remodeling during the critical period for visual development in the cat, the researchers believe the finding has broader implications, not just for plasticity during development in other brain structures, but for plasticity in the adult brain.

    If this is shown to be the case, sleep could prove an important part of the strategy for preparing for such challenges as exams. "The fact that sleep provoked slightly more plasticity than double the amount of exposure to experience [when cats remained awake in a lit room] suggests that if you reviewed your notes thoroughly until you were tired and then slept, you'd achieve as much plasticity, or 'learning,' in the brain as if you'd pulled an all-nighter repeating your review of the material," says Stryker.

    Significantly, the researchers determined that the amount of plasticity in the brain depended on the amount of sleep known as non-rapid eye movement, a deep, quiet, slumber marked by large, slow brain waves. This is the sleep that a person falls into when he or she first goes to sleep and which accounts for half of sleep in animals of this age. Non-REM sleep alternates with periods of rapid eye movement, or so-called "dream" sleep, a period marked by rapidly changing brain waves and rapid bursts of eye movement.

    This discovery offers direction for examining the two major hypotheses for how sleep impacts plasticity. One theory is that patterned neuronal activity following a period of environmental stimulation is replayed during non-REM sleep, strengthening neuronal connection changes. The alternative theory, which could also work in conjunction with the first, is that powerful growth factors, such as neurotrophins, which are known to be necessary for cortical plasticity, are released during non-REM sleep.


  8. Mirror Self-Recognition In The Bottlenose Dolphin: A Case Of Cognitive Convergence, PNAS Next Article Bookmark and Share

    Abstract: The ability to recognize oneself in a mirror is an exceedingly rare capacity in the animal kingdom. To date, only humans and great apes have shown convincing evidence of mirror self-recognition. Two dolphins were exposed to reflective surfaces, and both demonstrated responses consistent with the use of the mirror to investigate marked parts of the body. This ability to use a mirror to inspect parts of the body is a striking example of evolutionary convergence with great apes and humans.

    1. Brainy Dolphins Pass the Human 'Mirror' Test, NYTimes Next Article Bookmark and Share

      Excerpts: (…) dolphins are able to recognize themselves in mirrors - often taken as a sign of self-awareness - and of spontaneously grasping the thoughts of other individuals, in this case, humans.

      (…)dolphins can develop some notion of themselves and others as distinct individuals, abilities often associated only with humans and great apes.

      "opens the discussion about brain evolution because the brains of primates and dolphins have evolved along very different lines for more than 60 million years."


  9. A Neural Correlate Of Syntactic Encoding During Speech Production, PNAS Next Article Bookmark and Share

    Excerpts: Spoken language is one of the most compact and structured ways to convey information. (…)With the use of positron emission tomography we investigated the cortical activations during spoken language production that are related to the syntactic encoding process. In the paradigm of restrictive scene description, utterances varying in complexity of syntactic encoding were elicited. Results provided evidence that the left Rolandic operculum, caudally adjacent to Broca's area, is involved in both sentence-level and local (phrase-level) syntactic encoding during speaking.

  10. Computational Modeling Of Visual Attention Laurent, Nature Next Article Bookmark and Share

    How can our brain process the massive sensory input (estimated to be of the order of 107 -10 8 bits per sec at the optic nerve)? The ability to orient rapidly toward salient objects in a cluttered visual scene may be the purpose of 'attention'. It enables organisms to detect quickly a potential prey, mate or predator.

    Some stimuli are intrinsically salient in given context, say a flickering light in a static scene, automatically and involuntarily attracts attention. This suggests that saliency is computed in a pre-attentive manner across the entire visual field, most probably in terms of hierarchical 'center-surround mechanism' and the speed of such form of attention is in the order of 25-50 ms per item. The authors then present the second form of attention that involve variable selection criteria, depending upon the task at hand, for example, task of 'look at the red, horizontal line'. The expression of this top-down attention is most probably controlled from higher areas, including frontal lobes.

    The above two types of mechanisms can operate in parallel. Attention implements an information processing bottle neck that allows only a small part of the incoming sensory information to reach short term memory and visual awareness. So attention actually breaks down the problem of understanding a visual scene into a rapid series of computationally less demanding, localized visual problems. It is also characterized by a feedback modulation of neural activity for the visual attributes and at the location of the desired or selected activity. The authors focus on biologically plausible computational modeling of a saliency based form of focal bottom-up attention. The paper has illustrations with brief discussion on 1) neuronal mechanism for the control of attention, 2) Flow diagram of a typical model for the control of bottom-up attention, 3) Recording saliency and 4) Combined model of attentional selection and object recognition.

    Abstract: Five important trends have emerged from recent works on computational models of local visual attention that emphasize the bottom-up, image based control of attentional deployment. first the perceptual saliency of stimuli critically depend on the surrounding context. Second, a unique 'saliency map' that topographically encodes for stimulus conspicuity over the visual scene has proved to an efficient and plausible bottom-up control strategy. Third, the inhibition of return, the process by which the currently attended location is prevented from being attended again, is a crucial element of attentional deployment. Fourth, attention and eye movement tightly interplay, posing computational challenges with respect to the coordinate system used to control attention. And last, scene understanding and object recognition strongly constrain the selecting of attended locations. Insight from the five key areas provide a framework of computational and neuro biological understanding of visual attention.


  11. Cortical Deafness To Dissonance, Brain Next Article Bookmark and Share

    Excerpts: Ordinary listeners, including infants, easily distinguish consonant from dissonant pitch combinations and consider the former more pleasant than the latter. The preference for consonance over dissonance was tested in a patient, I.R., who suffers from music perception and memory disorders as a result of bilateral lesions to the auditory cortex. In Experiment 1, I.R. was found to be unable to distinguish consonant from dissonant versions of musical excerpts taken from the classical repertoire by rating their pleasantness. I.R.'s indifference to dissonance was not due to a loss of all affective responses to music, however, since she rated the same excerpts as happy or sad, as normal controls do. (…) Taken together, the findings suggest that dissonance may be computed bilaterally in the superior temporal gyri by specialized mechanisms prior to its emotional interpretation.

  12. Sex Matters, National Academy Of Sciences/Institute Of Medicine Next Article Bookmark and Share

    Abstract: A new IOM study, "Exploring the Biological Contributions to Human Health: Does Sex Matter?", reports that sex, that is, being male or female, is an important basic human variable that should be considered when designing and analyzing studies in all areas and at all levels of biomedical and health-related research. But while it is anatomically obvious why only males develop prostate cancer and only females get ovarian cancer, it is not at all obvious why, for example, females are more likely than males to recover language ability after suffering a left-hemisphere stroke, or why females have a far greater risk than males of developing life-threatening ventricular arrhythmias in response to a variety of potassium channel-blocking drugs. According to the new report, basic biochemical differences in cells of males and females contribute to health variability between the sexes. The report examines current knowledge on the mechanisms and origins of sex-related differences in human health and illness and addresses ethical, financial, sociological, and scientific challenges and opportunities in the future of research. A summary and the report itself are available online, respectively, at

  13. Prostate Cancer Complexity, Tracking The Disease's Genetic Roots Presents Enormous Challenges, The Scientist Next Article Bookmark and Share

    Excerpt: Trying to explain and predict metastasis is yet one more piece of an exceedingly complicated puzzle that has thus far baffled researchers. Albright concedes that environmental or other gene interactors might be more important in the case of prostate cancer than genetically well-described cancers such as breast or colon. (...) "The picture is actually way more complex than breast cancer," she comments. "But that's what we're all going to say while we're not successful--'It's because it's so complex.'"

  14. Glial Cells And The Synapse, Science Next Article Bookmark and Share

    Glial cells participate in the regulation of synaptic transmission by controlling neurotransmitter diffusion and concentration in the synaptic cleft. Two reports explore the role of glutamate and its receptors in this control (see the Perspective by Gallo and Chittajallu). To investigate the role of glial glutamate uptake, Oliet et al. (p. 923) took advantage of a substantial anatomical rearrangement between astrocytes and neurons in the hypothalamus during changes in reproductive state. During lactation, astrocyte ensheathment of synapses and hence glutamate removal are reduced, which leads to changes in the amplitude of evoked excitatory postsynaptic currents caused by activation of presynaptic metabotropic glutamate receptors. Glial cells express AMPA glutamate receptor subunits, the physiological role of which has been poorly understood. Iino et al. (p. 926) altered the function of Bergmann glial cells in the cerebellum by adding an AMPA receptor subunit that renders the channels calcium impermeable. They observed major changes in the morphology of the glial cell specializations around the synapses: The glial envelopment around Purkinje cell dendritic spines became retracted. Removal of released


    1. Unwrapping Glial Cells From The Synapse: What Lies Inside?, Science Next Article Bookmark and Share

      Excerpts: The central nervous system houses two main kinds of cells--neurons, which move information around the brain in the form of electrical signals, and glia, which until relatively recently have been considered to fulfill only a supportive role. However, an exciting possibility is emerging--the major type of glia, the astrocyte, seems actually to be required for synapse formation and maintenance, and for synaptic efficacy

      The long, thin processes of astrocytes ensheathe the synaptic connections between neurons and are therefore well positioned anatomically to contribute to synaptic transmission.


    2. Control Of Glutamate Clearance And Synaptic Efficacy By Glial Coverage Of Neurons, Science Next Article Bookmark and Share

      Abstract: Analysis of excitatory synaptic transmission in the rat hypothalamic supraoptic nucleus revealed that glutamate clearance and, as a consequence, glutamate concentration and diffusion in the extracellular space, is associated with the degree of astrocytic coverage of its neurons. Reduction in glutamate clearance, whether induced pharmacologically or associated with a relative decrease of glial coverage in the vicinity of synapses, affected transmitter release through modulation of presynaptic metabotropic glutamate receptors. Astrocytic wrapping of neurons, therefore, contributes to the regulation of synaptic efficacy in the central nervous system.


    3. Glia-Synapse Interaction Through Ca2+-Permeable AMPA Receptors In Bergmann Glia, Science Next Article Bookmark and Share

      Excerpts: Glial cells express a variety of neurotransmitter receptors. (…) To elucidate the role of these Ca2+-permeable AMPARs, we converted them into Ca2+-impermeable receptors by adenoviral-mediated delivery of the GluR2 gene. This conversion retracted the glial processes ensheathing synapses on Purkinje cell dendritic spines and retarded the removal of synaptically released glutamate. Furthermore, it caused multiple innervation of Purkinje cells by the climbing fibers. Thus, the glial Ca2+-permeable AMPARs are indispensable for proper structural and functional relations between Bergmann glia and glutamatergic synapses.


  15. Integrated Genomic And Proteomic Analyses Of A Systematically Perturbed Metabolic Network, Science Next Article Bookmark and Share

    Excerpts: We demonstrate an integrated approach to build, test, and refine a model of a cellular pathway, in which perturbations to critical pathway components are analyzed (…). Using this approach, we identify 997 messenger RNAs responding to 20 systematic perturbations of the yeast galactose-utilization pathway, provide evidence that approximately 15 of 289 detected proteins are regulated posttranscriptionally,(…). We refine the model through further iterations of perturbation and global measurements, suggesting hypotheses about the regulation of galactose utilization and physical interactions between this and a variety of other metabolic pathways.

  16. Circadian Rhythms In Plants, Annu. Rev. Plant Physiol. Plant Mol. Biol Next Article Bookmark and Share

    Abstract:Circadian rhythms, endogenous rhythms with periods of approximately 24 h, are widespread in nature. Although plants have provided many examples of rhythmic outputs and our understanding of photoreceptors of circadian input pathways is well advanced, studies with plants have lagged in the identification of components of the central circadian oscillator. Nonetheless, genetic and molecular biological studies, primarily in Arabidopsis, have begun to identify the components of plant circadian systems at an accelerating pace. There also is accumulating evidence that plants and other organisms house multiple circadian clocks both in different tissues and, quite probably, within individual cells, providing unanticipated complexity in circadian systems.


  17. Complex Manoeuvres, Financial Times Next Article Bookmark and Share

    It seems Kehoe uses the word "complex" synonymously with the word "complicated" in the sense of "hard to understand". Things that have many parts often are also more complicated. One of the contributions of complex systems theory is that it shows that universal order parameters can emerge through self-organization that make the complex system behave coherently with a substantial simplification of the behavior.

    In a sense that is really what she is describing with software: there are too many components that interact poorly because of lack of integration.

    The example she mentions is from an Oracle White Paper that talks about integration as a way to reduce complexity (in the sense of difficulties) for the users. As she mentions, that is done with an engineering strategy that has been used by IBM and Microsoft before. Oracle even recommends centralization of information which really is a step back to the old mainframe idea with terminal access instead of the networked client/server structure.

    An alternative approach is to use open standards where independent components ("objects") are built in a way that they can interact efficiently. The first approach is necessarily brittle: if you build more and more features into a centralized program, it will become more and more dependent on the design strategy of one single company (IBM, Microsoft, Oracle) whereas open source standards seem to be much more adaptive and robust.

    Therefore I would think that platform independent languages like java are more like order parameters of complex systems. In fact the emergence of languages is one of Hermann Haken's standard examples of self-organization in synergetics. It certainly also seems to apply to computer languages.

    Excerpts: Watch for "complexity" to become the next "bad technology" buzzword. It covers a multitude of sins and, unlike many technology terms that have swung from being positive to pejorative over the past year, complexity has never been a good thing.

    We have all felt the effects of software complexity. (…)

    At the corporate level, complexity means cost - the cost of implementing a new e-business application or of integrating a new application with existing "legacy" systems.


    1. Winning The War On Complexity, Oracle White Paper Next Article Bookmark and Share

      Excerpts: "To find the answers to simple questions, such as how many employees we had, we would literally have to go out and touch 60 databases,"(…)

      Many global enterprises add unnecessary complexity to their operations by distributing the workload to local systems. For these organizations, simplifying IT activities involves buying software applications that support consistent, worldwide operations from a single instance of the software. These centralized implementations can be accessed from any point on the globe via a simple Web browser.


    2. Complex or Simple? Four Ways to Tell If You're Really an E-Business, Oracle.com Next Article Bookmark and Share

      Complex: You bought kits made up of point solutions from different vendors. Then, you spend even more money (maybe as much as 80 percent of your IT budget) to integrate, customize, and implement them.

      Simple: You bought one, integrated suite. You spend your resources on your core business-and strengthen your position in the marketplace.

      Complex: You focus on isolated business functions. You think your business is about separate activities-call center, marketing, sales, inventory-and you select different applications for each one.

      Simple: You focus on business flows. You know your business is about integrated, connected process flows


  18. Mutation, Selection, And Vertical Transmission Of Theistic Memes In Religious Canons, J. Memetics Next Article Bookmark and Share

    Recently moral and social norms have been considered as emerging from cultural evolution, maximizing the survival probabilities of the societies following these norms. On the other hand, moral and social norms can be changed in different ways in order to increase the survival probability when they affect it. This work focuses on the evolution of religious canons, studying it from the memetics perspective.

    Abstract: A study of ancient and modern Near Eastern religious canons reveals the mutation, selection, and vertical transmission of fitness-enhancing textual units, defined as theistic memes. The earliest recorded theistic memes dealt with human fear of death and defined man's earliest relationship to god. Theistic memes that could theoretically affect fitness through selection and incorporation into religious canons included those dictating beliefs about (a) self-awareness in an unknown world, (b) strategies and behaviors toward others and within the nuclear family, and (c) appropriate sexual behaviors within marriage. Prohibition of aberrant sexual practices such as incest, adultery, homosexuality, bestiality, castration, and religious prostitution would have further maximized fitness. A remarkable mutation of the ancient Near Eastern theistic meme of child sacrifice is documented in the Old Testament in the story of Abraham and Isaac. Vertically transmitted theistic memes in the Hebrew canon were largely incorporated into Christian and Muslim religious canons (New Testament and Qur'an). Mutations of theistic memes during vertical transmission into these other canons allowed the same fitness-enhancing stability for the gentile and Arabic populations and are notable for the different strategies used to produce homogenized, orthodox canons.


  19. Is Suicide Contagious?, J. Memetics Next Article Bookmark and Share

    Abstract: The phenomenon of suicide contagion is demonstrated experimentally. An interpretation of the results is proposed using an understanding of memetics as contagion psychology informed by selectionist thinking. Using the term `meme' to denote an object of contagion and `contagion' to denote a process of spread by exposure, a selectionist explanation of why certain people might be susceptible to a contagion of suicide is provided. Specifically, it is suggested that people who have become socially isolated and culturally disenfranchised, i.e. those with reduced residual cultural fitness (compromised access to the means of cultural reproduction), might be at particular risk from suicide contagion. Finally, public health policy implications of this memetic understanding of suicide are briefly outlined.

  20. Links & Snippets Next Article Bookmark and Share

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

      1. Clustering and Preferential Attachment in Growing Networks, M. E. J. Newman, SFI WP 01-03-021
      2. Synchronizing to the Environment: Information Theoretic Constraints on Agent Learning, James P. Crutchfield and David P. Feldman, SFI WP 01-03-020
      3. Interfaces (and Regional Congruence?) in Spin Glasses, C. M. Newman and D. L. Stein, SFI WP 01-03-019
      4. Stochastic Economies with Locally Interacting Agents, I. V. Evstigneev and M. I. Taksar, SFI WP 01-03-018
      5. The Conservation of Homochirality and the Prebiotic Synthesis of Amino Acids, Harold J. Morowitz, SFI WP 01-03-017

    2. TheScientificWorld Pub Alert: "Complexity" 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.

      1. Reduced Complexity Decoding of Low Density Parity Check Codes for Generalized Partial Response Channels, Mittelholzer, T.; Dholakia, A.; Eleftheriou, E., IEEE TRANSACTIONS ON MAGNETICS MAG
      2. The Emergent Ego: Complexity and Coevolution in the Psychoanalytic Process, by Stanley R. Palombo, M.D, Glucksman, M. L., JOURNAL- AMERICAN ACADEMY OF PSYCHOANALYSIS
      3. Infinite Variety and Complexity: An Urgent Challenge for Psychoanalysis, Eckardt, M. H., JOURNAL- AMERICAN ACADEMY OF PSYCHOANALYSIS
      4. New experiences with absolute ethanol sclerotherapy in the management of a complex form of congenital venous malformation, Lee, B. B.; Kim, D. I.; Huh, S.; Kim, H. H.; Choo, I. W.; Byun, H. S.; Do, Y. S., JOURNAL OF VASCULAR SURGERY
      5. Forecasting and warning of water related disasters in a complex hydraulic setting - the case of Bangladesh, Paudyal, G. N., JOURNAL- INDIAN WATERWORKS ASSOCIATION
      6. Geometrical renormalization approach to calculating optical properties of fractal carbonaceous soot, MARKEL (Vadim A.); SHALAEV (Vladimir M.), Journal of the Optical Society of America. A, Optics and image science
      7. Statistical Properties of Inter-Series Mixing in Helium: From Integrability to Chaos, PUTTNER (R.); GREMAUD (B.); DELANDE (D.); DOMKE (M.); MARTINS (M.); SCHLACHTER (A. S.); KAINDL (G.), Physical review letters
      8. Complex causes of amphibian population declines, Kiesecker, J. M.; Blaustein, A. R.; Belden, L. K., NATURE -LONDON-
      9. The Complexity of Heart Rate in Its Postnatal Development, Mrowka, R.; Patzak, A.; Persson, P. B., IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE
      10. Constrained inversion of gravity fields for complex 3-D structures, Moraes, R. A. V.; Hansen, R. O., GEOPHYSICS -WISCONSIN THEN TULSA- SOCIETY OF EXPLORATION GEOPHYSICISTS-
      11. Complex Systems: Chaos and Beyond, K Kaneko & I Tsuda, Shlesinger, M. F., NATURE -LONDON-
      12. Impact of Overlapping Recruitment on Linkage Analysis of Complex Disorders: Simulation Studies, Davis, S.; Nimgaonkar, V. L., AMERICAN JOURNAL OF MEDICAL GENETICS
      13. Complexity results and approximation algorithms for the two machine no-wait flow-shop with limited machine availability, ESPINOUSE (M-L); FORMANOWICZ (P.); PENZ (B.), The Journal of the Operational Research Society
      14. Complex climate models - tools for studying the origin of stochasticity in the climate system, von Storch, J.-S., PROGRESS IN PROBABILITY
      15. Enterprise security management : Managing complexity, NYANCHAMA (Matunda); SOP (Paul), Information systems security
      16. Validation of Atmospheric Dispersion Model for Complex Terrain, Suh, K. S.; Kim, E. H.; Hwang, W. T.; Choi, Y. G.; Han, M. H.; Kim, H. S., FRONTIERS SCIENCE SERIES
      17. Application of Uncertainty Analysis to A Complex Computer Simulation Model: Use in Fire Protection Engineering Design, Notarianni, K. A.; Fischbeck, P. S., FRONTIERS SCIENCE SERIES
      18. The effects of complexity, of simplicity and of scaling in thermal-hydraulics, Zuber, N., NUCLEAR ENGINEERING AND DESIGN
      19. IDACrew: A Cognitive Model of Operating Crew Response to Complex System Accidents, Chang, Y. H.; Mosleh, A.; Shen, S. H., FRONTIERS SCIENCE SERIES
      20. ADS-IDACrew: Dynamic Probabilistic Simulation of Operating Crew Response to Complex System Accidents, Chang, Y. H.; Mosleh, A., FRONTIERS SCIENCE SERIES
      21. Effects of exercise and passive head-up tilt on fractal and complexity properties of heart rate dynamics, TULPPO (Mikko P.); HUGHSON (Richard L.); MÄKIKALLIO (Timo H.); AIRAKSINEN (K. E. Juhani); SEPPÄNEN (Tapio); HUIKURI (Heikki V.), American journal of physiology. Heart and circulatory physiology
      22. The impact of disruption and delay when compressing large projects : going for incentives?, HOWICK (S.); EDEN (C.), The Journal of the Operational Research Society
      23. The complexity of social networks: theoretical and empirical findings, Butts, C. T., SOCIAL NETWORKS
      24. Complex Chemical Stabilization of Dichlorodiphosphene, Vogel, U.; Stosser, G.; Scheer, M., ANGEWANDTE CHEMIE -INTERNATIONAL EDITION IN ENGLISH-
      25. The activation-relaxation technique : an efficient algorithm for sampling energy landscapes, BARKEMA (G. T.); MOUSSEAU (Normand), Computational materials science
      26. Brain potentials in human patients with extremely severe diffuse brain damage, KOTCHOUBEY (B.); LANG (S.); BAALES (R.); HERB (E.); MAURER (P.); MEZGER (G.); SCHMALOHR (D.); BOSTANOV (V.); BIRBAUMER (N.), Neuroscience letters
      27. Asthma und Allergie : Genetische Prädisposition und Umweltfaktoren : Asthma, KABESCH (M.), Monatsschrift für Kinderheilkunde
      28. Hydrological modeling using artificial neural networks, DAWSON (C. W.); WILBY (R. L.), Progress in physical geography
      29. The application of non-parametric techniques to solve classification problems in complex data sets in veterinary epidemiology - An example, Stark, K. D.; Pfeiffer, D. U., INTELLIGENT DATA ANALYSIS
      30. Characterizations, bounds, and probabilistic analysis of two complexity measures for linear programming problems, TODD (Michael J.); TUNCEL (Levent); YINYU YE, Mathematical programming
      31. Cellular automata: From a theoretical parallel computational model to its application to complex systems, Bandini, S.; Mauri, G.; Serra, R., PARALLEL COMPUTING -AMSTERDAM-
      32. A finite element-based identification method for complex metallic material behaviours, Ghouati, O.; Gelin, J. C., COMPUTATIONAL MATERIALS SCIENCE
      33. Soliton complex dynamics in strongly dispersive medium, Bogdan, M. M.; Kosevich, A. M.; Maugin, G. A., WAVE MOTION
      34. New architectures for constructed complex systems, Landauer, C.; Bellman, K. L., APPLIED MATHEMATICS AND COMPUTATION -ELSEVIER-
      35. Autonomous control of complex systems: robotic applications, Jamshidi, M., APPLIED MATHEMATICS AND COMPUTATION -ELSEVIER-
      36. Hysteresis in three-phase flow: Experiments, modeling and reservoir simulations, EGERMANN (P.); VIZIKA (O.); DALLET (L.); REQUIN (C.); SONIER (F.),
      37. Two-dimensional random adaptive sampling for image scanning, LO PRESTI (Letizia); D'AMATO (Giacomo); SAMBUELLI (Luigi), IEEE transactions on geoscience and remote sensing
      38. Geometrical renormalization approach to calculating optical properties of fractal carbonaceous soot, MARKEL (Vadim A.); SHALAEV (Vladimir M.), Journal of the Optical Society of America. A, Optics and image science
      39. Chaos control and taming of turbulence in plasma devices, KLINGER (Thomas); SCHRODER (Christiane); BLOCK (Dietmar); GREINER (Franko); PIEL (Alexander); BONHOMME (Gerard); NAULIN (Volker), Physics of plasmas
      40. Intermarriage, Social Complexity, and Ethnic Diversity in the Genealogy of Judah, Knoppers, G. N., JOURNAL OF BIBLICAL LITERATURE
      41. Synchronization and self-organization in arrays of coupled solid-state lasers, CHABANOL (M.); ZEHNLE (V.), Physical review. A
      42. Hydrological modelling using artificial neural networks, DAWSON (C. W.); WILBY (R. L.), Progress in physical geography
      43. Effects of exercise and passive head-up tilt on fractal and complexity properties of heart rate dynamics, TULPPO (Mikko P.); HUGHSON (Richard L.); MÄKIKALLIO (Timo H.); AIRAKSINEN (K. E. Juhani); SEPPÄNEN (Tapio); HUIKURI (Heikki V.), American journal of physiology. Heart and circulatory physiology
      44. Organizations and Complexity: Searching for the Edge of Chaos, Carroll, T.; Burton, R. M., COMPUTATIONAL AND MATHEMATICAL ORGANIZATION THEORY
      45. A model for complex aftershock sequences (Paper 2000JB900396), Moreno, Y.; Correig, A. M.; Gomez, J. B.; Pacheco, A. F., JOURNAL OF GEOPHYSICAL RESEARCH -ALL SERIES-
      46. Robotic cells Two robotic welding cells have automated the manufacture of complex assemblies for the new Jaguar saloon, Unknown Author, METALWORKING PRODUCTION
      47. Schizotypy and latent inhibition : non-linear linkage between psychometric and cognitive markers, WUTHRICH (Viviana); BATES (Timothy C.), Personality and individual differences
      48. Linkage Analysis of a Complex Pedigree with Severe Bipolar Disorder, Using a Markov Chain Monte Carlo Method, Garner, C.; McInnes, L. A.; Service, S. K.; Spesny, M.; Fournier, E.; Leon, P.; Freimer, N. B., AMERICAN JOURNAL OF HUMAN GENETICS
      49. Advanced life-cycle model for complex product development via stage-aligned information-substitutive concurrency and detour, Tianfield, H., INTERNATIONAL JOURNAL OF COMPUTER INTEGRATED MANUFACTURING
      50. The Theoretical Background of Contemporary Integrated Manufacturing Systems: One Type of Complexity Problems and Its Solution, Wu, C., COMPUTER INTEGRATED MANUFACTURING SYSTEMS -BEIJING-
      51. The Communication Complexity of Pointer Chasing, Ponzio, S. J.; Radhakrishnan, J.; Venkatesh, S., JOURNAL OF COMPUTER AND SYSTEM SCIENCES
      52. On the Complexity of k-SAT, Impagliazzo, R.; Paturi, R., JOURNAL OF COMPUTER AND SYSTEM SCIENCES
      53. Wind - excited random vibration of complex structures, Dongke, S.; Jiahao, L.; Yahui, Z., CHINESE JOURNAL OF MECHANICAL ENGINEERING
      54. The role of age, foreknowledge and complexity in learning to operate a complex device, Freudenthal, D., BEHAVIOUR AND INFORMATION TECHNOLOGY
      55. Information-Based Complexity of Uncertainty Sets in Feedback Control, Wang, L. Y.; Lin, L., IEEE TRANSACTIONS ON AUTOMATIC CONTROL
      56. Cardiac Surgery Increases Surgical Complexity, Glower, D. D.; Stafford-Smith, M.; Clements, F. M., ANESTHESIOLOGY -PHILADELPHIA THEN HAGERSTOWN-
      57. On the complexity of a class of combinatorial optimization problems with uncertainty, Averbakh, I., MATHEMATICAL PROGRAMMING
      58. Chronic epilepsy with complex partial seizures is not always medically intractable - a long-term observational study, Trinka, E.; Martin, F.; Luef, G.; Unterberger, I.; Bauer, G., ACTA NEUROLOGICA SCANDINAVICA
      59. Ergodic Theory of Complex Systems, Entropy and Applications, Wang, Q., JOURNAL- TONGJI UNIVERSITY
      60. Study of Complex Systems on PEP Polymer Surfactant, Zhou, L.; Hao, F.-q.; Liu, B., JOURNAL OF FUNCTIONAL POLYMERS
      61. Unsupervised Learning and Temporal Context to Recall Complex Robot Trajectories, De, G.; Barreto, A.; Araujo, A. F. R., INTERNATIONAL JOURNAL OF NEURAL SYSTEMS
      62. Virtual Practices, Complex Epistemologies, Hulsbus, M., CONVERGENCE -LONDON-
      63. COMPLEX TRAIT ANALYSIS IN THE MOUSE: THE STRENGTHS, THE LIMITATIONS, AND THE PROMISE YET TO COME, Moore, K. J.; Nagle, D. L., ANNUAL REVIEW OF GENETICS
      64. Restricted feedback control of one-dimensional maps, HALL (Kevin); CHRISTINI (David J.), Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics
      65. Multifractal characterization of stochastic resonance, SILCHENKO (Alexander); HU (Chin-Kun), Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics
      66. Organizational Complexity and Perceptions of Risk, McKenna, S., RISK MANAGEMENT -LEICESTER-
      67. Beyond resources: Formal models of complexity effects and age differences in working memory, Oberauer, K.; Kliegl, R., EUROPEAN JOURNAL OF COGNITIVE PSYCHOLOGY
      68. Method and Complexity in Bioethics: The Example of Community Genetics, Cleret de Langavant, G., COMMUNITY GENETICS
      69. Patient Dose Related to the Complexity of Interventional Cardiology Procedures, Padovani, R.; Bernardi, G.; Malisan, M. R.; Vano, E.; Morocutti, G.; Fioretti, P. M., RADIATION PROTECTION DOSIMETRY
      70. Refinery feed, complexity determine, SIELI (G.M.), Oil and Gas Journal
      71. Women's travel patterns and the environment : An agenda for research, SCHINTLER (Laurie); ROOT (Amanda); BUTTON (Kenneth), Transportation research record


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