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friday :: may 26, 2006
   
 
evolution: cheats don't always prosper

Selfishness is not necessarily the best survival trait for microorganisms, according to researchers studying the comparative effectiveness of 'cheating' and 'cooperating' strains of yeast.

Scientists reports that studies of lab-grown yeast populations suggest the benefits of cheating are eventually counterbalanced by the costs. This contradicts classic evolutionary theory, which states that in a competition for common resources the long-term winner will always be the individual acting selfishly rather than the one working as part of a group.

To test this theory, scientists set up a series of competitions between two strains of yeast. The strains are identical apart from the genes that determine whether they convert energy from resources such as sugar rapidly or if they convert it efficiently.

In one corner were the 'cooperators', which produce energy efficiently by taking in sugar slowly and fully converting into energy all that they ingest. This method maximises resources available to the group by avoiding any waste.

Against them were the 'cheaters', which produce energy rapidly by quickly taking in all the sugar they can and only partially converting it into energy. While this ensures swift energy production for the individual, it is a wasteful method that reduces resources available for the group as a whole.

The researchers were surprised to find that in a well-mixed population the cooperators were not excluded by the cheats. Further experiments and mathematical modelling established that this is because cheats accumulate toxins as a direct result of taking in resources more quickly than they can digest them, which limits the level of energy they derive from the sugar. This enables the cooperators to hold their own, meaning that the two different strains could coexist over the long-term without either being excluded. Lead researcher Dr Craig MacLean of Imperial College London says: "This evidence that a cooperative group can resist invasion by exploitative cheats is unexpected and gives us greater insight into how cooperation evolves. This is important because we live in a world in which cooperations exists at every level, from genes working together to build functioning individuals to individuals forming societies."

The researchers suggest that the ideal organism type would be one that can switch between selfish and efficient metabolism. Dr MacLean adds: "While microbes are obviously not capable of rational thought, they can change their behaviour rapidly in response to simple environmental cues. The possibility that one type could become both a cheater and a cooperator depending on what's needed at the time is intriguing. We hope examining social conflict at the level of individual cells will shed more light on this." >from *Survival of the selfless - scientists find cheats don't always prosper*. May 24, 2006

related context
>
game theory. 'studies choice of optimal behavior when costs and benefits of each option are not fixed, but depend upon the choices of other individuals.' via victor
> why we give. december 30, 2005
> revenge: neural basis of altruistic punishment. 'cooperation flourishes if altruistic punishment is possible, and breaks down if it is ruled out.' september 10, 2004
> others' intentions. march 5, 2004
> cooperation evolution. october 8, 2003
> commons-based peer production in the digitally networked environment. december 19, 2002
> neurophysiology of sympathy: patterns of brain activity. december 10, 2002
> human cooperation: biological basis revealed. july 19, 2002
> cooperation and affiliation: primary social behavior in primates. february 25, 2002

imago
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cheat: not a chance

sonic flow
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cheats accumulate toxins [stream]
cheats accumulate toxins [download]

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friday :: may 19, 2006
   
 
the big bounce universe

According to Einstein's general theory of relativity, the Big Bang represents The Beginning, the grand event at which not only matter but space-time itself was born. While classical theories offer no clues about existence before that moment, a research team at Penn State has used quantum gravitational calculations to find threads that lead to an earlier time. “General relativity can be used to describe the universe back to a point at which matter becomes so dense that its equations don't hold up,” says Abhay Ashtekar, Director of the Institute for Gravitational Physics and Geometry at Penn State. “Beyond that point, we needed to apply quantum tools that were not available to Einstein.” By combining quantum physics with general relativity, Ashtekar and post-doctoral researchers, Tomasz Pawlowski and Parmpreet Singh, were able to develop a model that traces through the Big Bang to a shrinking universe that exhibits physics similar to ours.

In research reported, the team shows that, prior to the Big Bang, there was a contracting universe with space-time geometry that otherwise is similar to that of our current expanding universe. As gravitational forces pulled this previous universe inward, it reached a point at which the quantum properties of space-time cause gravity to become repulsive, rather than attractive. “Using quantum modifications of Einstein's cosmological equations, we have shown that in place of a classical Big Bang there is in fact a quantum Bounce,” says Ashtekar. “We were so surprised by the finding that there is another classical, pre-Big Bang universe that we repeated the simulations with different parameter values over several months, but we found that the Big Bounce scenario is robust.”

While the general idea of another universe existing prior to the Big Bang has been proposed before, this is the first mathematical description that systematically establishes its existence and deduces properties of space-time geometry in that universe.

The research team used loop quantum gravity, a leading approach to the problem of the unification of general relativity with quantum physics, which also was pioneered at the Penn State Institute of Gravitational Physics and Geometry. In this theory, space-time geometry itself has a discrete 'atomic' structure and the familiar continuum is only an approximation. The fabric of space is literally woven by one-dimensional quantum threads. Near the Big-Bang, this fabric is violently torn and the quantum nature of geometry becomes important. It makes gravity strongly repulsive, giving rise to the Big Bounce.

"Our initial work assumes a homogenous model of our universe," says Ashtekar. "However, it has given us confidence in the underlying ideas of loop quantum gravity. We will continue to refine the model to better portray the universe as we know it and to better understand the features of quantum gravity." >from *Penn State Researchers Look Beyond the Birth of the Universe* . May 12, 2006

related context
>
cyclic model of the universe by paul j. steinhardt and neil turok. 'why the cosmological constant is small an positive.' may 4, 2006
> gravity-modification breakthrough. 'scientists have measured the gravitational equivalent of a magnetic field for the first time in a laboratory. just as a moving electrical charge creates a magnetic field, so a moving mass generates a gravitomagnetic field. a significant step towards the quantum theory of gravity' march 23, 2006
> new satellite data on universe's first trillionth second. 'new evidence for what happened when the universe suddenly grew from microscopic quantum fluctuations to enable the formation of stars, planets and life. according to this picture, researchers say, only 4 percent of the universe is ordinary familiar atoms; another 22 percent is an as-yet unidentified dark matter, and 74 percent is a mysterious dark energy.' march 16, 2006
> gravitational wave research project. 'gravitational waves are ripples in the fabric of space and time produced by events in our galaxy and throughout universe.' july 30, 2004
> quantum universe. 'what is the nature of the universe and what is it made of? what are matter, energy, space and time? how did we get here and where are we going?.' june 11, 2004
> space/time atoms?: quantum gravity-based universe. 'the tiny scale at which the microscopic structure of space and time becomes observable is the planck scale.' february 26, 2003
> oldest light: milestone in cosmology. 'in addition, the new portrait precisely pegs the age of the Universe at 13.7 billion years old.' february 17, 2003
> in search of extra dimensions: beyond the standard model. 'somewhere within the planck scale, or at extreme energy levels, an incredibly small extra dimension may finally combine gravity and electromagnetism.' february 20, 2002
> search for gravity waves. '"gravitational waves are at the frontier of astrophysics. there's no question they exist, but they have not yet been detected directly.' december 10, 2001


imago
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le forze d'eolo dialogo quantico

sonic flow
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big bounce [stream]
big bounce [download]

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friday :: may 12, 2006
   
 
genes in the brain change with experience at every age

Scientists have long known that brains need neural activity to mature and that sensory input is most important during a specific window of time called the 'critical period' when the brain is primed for aggressive learning. Vision, hearing and touch all develop during such critical periods, while other senses, such as the olfactory system, maintain lifelong plasticity.

A new study focusing on the molecular roots of plasticity has found that visual stimulus turns up the expression of some genes and turns down the expression of others, somewhat like a conductor cueing the members of an orchestra. The study also found that during different stages of life in rodents, distinct sets of genes spring into action in response to visual input. These gene sets may work in concert to allow synapses and neural circuits to respond to visual activity and shape the brain.

The investigators' identification of many distinct sets of activity-dependent genes follows a shift in neuroscience research toward a more holistic view of the role of genes in neural development and plasticity.

First author Marta Majdan and co-author Carla Shatz, and Nathan Marsh Pusey, studied rodents during the critical period in which visual input stimulates aggressive plasticity, shaping the mesh of neural connections in the cortex and tuning the strengths of messages relayed by synapses. In mice, this period begins shortly after they open their eyes and begin to see. Previous research had determined that visual activity changes the level of expression of, or regulates, individual genes.

The researchers found other sets of genes superimposed on this core pathway, but these sets are turned on and off by vision at specific ages before, during and after the critical period and into adulthood.

"This suggests that sensory experience regulates different genes in your brain depending on your age and past experience," said Shatz. "Thus, nurture, our experience of the world via our senses, acts through nature, sets of genes, to alter brain circuits."

This study helps explain why it is that children learn so quickly and easily, and it lends credence to the idea that, in adults, mental activity leads to mental agility.

"It is amazing that, even in our oldest mice we saw genes regulated by vision. Genes in the brain change with experience at every age, forming a basis for our ability to learn and remember even in adulthood," said Shatz. >from *Research Shows How Visual Stimulation Turns Up Genes to Shape the Brain* . May 1, 2006

related context
>
brain is a dynamic network. 'brain is not a huge fixed network, as had been previously thought, but a dynamic, changing network that adapts continuously.' october 15, 2003
> synaptic plasticity: how experiences rewire the brain. 'rewiring of the brain involves the formation and elimination of synapses, the connections between neurons. the traditional view of neural development has been that when animals mature, the formation of synapses ceases.' january 23, 2003
> neurogenesis observed in human adult brain. 'new cells in the adult brain grow and mature over time. this landmark study upset long-held dogma that stated we are born with a full supply of brain cells that steadily diminish throughout our lives.' march 6, 2002
> how genes affect brain structure. 'brain mapping researchers have created the first images to show how an individual's genes influence their brain structure and intelligence. the amount of gray matter in frontal brain regions was strongly inherited, and also predicted an individual's iq score.' november 4, 2001

imago
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gen expandable orchestra

sonic flow
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activity-dependent genes [stream]
activity-dependent genes [download]

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friday :: may 5, 2006
   
 
net community hacks cultural funding system

“Our much-discussed, game-theory-oriented approach to cultural funding represents a clear rejection of all the Austrian cultural industry's hegemonic tendencies,” states MANA coordinator Stefan Lutschinger: “This hack of the outmoded jury and committee system opposes every rationalistic funding cut with pure difference, contingency coping and the fruitful development of paradox.”

Software-based Funding Distribution

Last week, a participatory cultural support budget of 125,000 euros was distributed to artists and cultural producers in Vienna using the MANA Community Game – an innovative software-supported selection process. The decision regarding the distribution of funding was not made by curators, juries or committees, but by the submitters themselves. Twelve people will receive project grants between 5,000 and 15,000 euros, whereby 42% of the recipients are women.

'Old' Concepts and 'New Thinking'

The Community Game is one of the most innovative distribution systems for cultural funding worldwide. It is based on 'old' concepts of the avant-garde – auto-curating and self-organization – and the 'new thinking' of second-order cybernetics. MANA's great advantage is its capacity for self-correction and adaptation to intelligent system environments: errors and irregularities can be recognized and corrected immediately by the net community, which emerges strengthened from this process. Here 120 submitters agreed to a complex set of rules.

A Self-managed Cultural Funding Budget

Since the autumn of 2004, the open net community 'netznetz.net' has grown out of the numerous digital cultural initiatives that have developed in Vienna in recent years. In order to do justice to these diverse cultural and artistic modes of expression, an application has been made to the City of Vienna's Department of Cultural Affairs (Net Culture Unit) for a self-managed cultural funding budget to support this very active scene with around 500,000 euros yearly. The heart of this funding model is the software-based selection process MANA. After a two-month evaluation phase in early summer, the net community will decide on its specific adaptation and further development. >from *Net Community Hacks Cultural Funding System* . May 2, 2006. via rama

related context
>
parliaments of art 2005. 'a symposium is organized for the viennese net culture community or meta community (netznetz.net) that in turn is building a software (mana) to organize its own workflows and future money distribution.' symposium & festival for the vienna star-up of the new funding model for net culture 2006. december 11-13, 2005
> MyCreativity: convention of international creative industries researchers. 'intends to bring the trends and tendencies around the creative industries into critical question.' amsterdam, november 17-18, 2006
> a new cultural movement?. 'the pioneers of active appropriation of digital technology are the diyers and hackers. this diy (do it yourself) approach is now assuming the form of a new cultural movement: the software becomes an engine of cultural innovation.' updated on october 22, 2003
> the search for organizational models for a post-web world. 'the theory of organizations needs to be recast in the context of cybernetics, graph and network theory as well as in the sciences of complexity, cognition and consciousness... architectures of 'collectives of collectives' on a planetary scale. within these emerging web sub structures there is a proliferation of cooperation, as well as collaborative projects for a variety of purposes and on a variety of scales. many such projects are 'temporary organizations' that seem to be characteristic of a well-connected network.' june 12, 2002

imago
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windmill machinery to hack public funds

sonic flow
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cultural funding system [stream]
cultural funding system [download]

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