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Advances in Neuroprosthetic Learning and Control

Advances in Neuroprosthetic Learning and Control | Papers | Scoop.it

Significant progress has occurred in the field of brain–machine interfaces (BMI) since the first demonstrations with rodents, monkeys, and humans controlling different prosthetic devices directly with neural activity. This technology holds great potential to aid large numbers of people with neurological disorders. However, despite this initial enthusiasm and the plethora of available robotic technologies, existing neural interfaces cannot as yet master the control of prosthetic, paralyzed, or otherwise disabled limbs. Here I briefly discuss recent advances from our laboratory into the neural basis of BMIs that should lead to better prosthetic control and clinically viable solutions, as well as new insights into the neurobiology of action.

 

Carmena JM (2013) Advances in Neuroprosthetic Learning and Control. PLoS Biol 11(5): e1001561. http://dx.doi.org/10.1371/journal.pbio.1001561

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Stochastic Model for the Vocabulary Growth in Natural Languages

Stochastic Model for the Vocabulary Growth in Natural Languages | Papers | Scoop.it

What cultural and social processes determine the size and growth of the vocabulary of a natural language? Does such a vocabulary grow forever? From large text databases, such as the Google Ngram, that have become available only recently, researchers tease out new and systematic insights into these fundamental questions and develop a mathematical model with predictive power that describes vocabulary growth as a simple stochastic process.

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Controllability Transition and Nonlocality in Network Control

 A common goal in the control of a large network is to minimize the number of driver nodes or control inputs. Yet, the physical determination of control signals and the properties of the resulting control trajectories remain widely underexplored. Here we show that (i) numerical control fails in practice even for linear systems if the controllability Gramian is ill conditioned, which occurs frequently even when existing controllability criteria are satisfied unambiguously, (ii) the control trajectories are generally nonlocal in the phase space, and their lengths are strongly anti-correlated with the numerical success rate and number of control inputs, and (iii) numerical success rate increases abruptly from zero to nearly one as the number of control inputs is increased, a transformation we term numerical controllability transition. This reveals a trade-off between nonlocality of the control trajectory in the phase space and nonlocality of the control inputs in the network itself. The failure of numerical control cannot be overcome in general by merely increasing numerical precision—successful control requires instead increasing the number of control inputs beyond the numerical controllability transition.

 

Controllability Transition and Nonlocality in Network Control
Jie Sun and Adilson E. Motter
Phys. Rev. Lett. 110, 208701 (2013)
http://prl.aps.org/abstract/PRL/v110/i20/e208701

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The Emergence of Environmental Homeostasis in Complex Ecosystems

The Emergence of Environmental Homeostasis in Complex Ecosystems | Papers | Scoop.it

Life on Earth is perhaps greater than three and a half billion years old and it would appear that once it started it never stopped. During this period a number of dramatic shocks and drivers have affected the Earth. These include the impacts of massive asteroids, runaway climate change and increases in brightness of the Sun. Has life on Earth simply been lucky in withstanding such perturbations? Are there any self-regulating or homeostatic processes operating in the Earth system that would reduce the severity of such perturbations? If such planetary processes exist, to what extent are they the result of the actions of life? In this study, we show how the regulation of environmental conditions can emerge as a consequence of life's effects. If life is both affected by and affects it environment, then this coupled system can self-organise into a robust control system that was first described during the early cybernetics movement around the middle of the twentieth century. Our findings are in principle applicable to a wide range of real world systems - from microbial mats to aquatic ecosystems up to and including the entire biosphere.

 

 Dyke JG, Weaver IS (2013) The Emergence of Environmental Homeostasis in Complex Ecosystems. PLoS Comput Biol 9(5): e1003050. http://dx.doi.org/10.1371/journal.pcbi.1003050

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Burstiness and spreading on temporal networks

We discuss how spreading processes on temporal networks are impacted by the shape of their inter-event time distributions. Through simple mathematical arguments and toy examples, we find that the key factor is the ordering in which events take place, a property that tends to be affected by the bulk of the distributions and not only by their tail, as usually considered in the literature. We show that a detailed modeling of the temporal patterns observed in complex networks can change dramatically the properties of a spreading process, such as the ergodicity of a random walk process or the persistence of an epidemic.

 

Burstiness and spreading on temporal networks

Renaud Lambiotte, Lionel Tabourier, Jean-Charles Delvenne

http://arxiv.org/abs/1305.0543

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Smart solutions from the plant kingdom

Plants represent almost 99.9% of the biomass of our planet. This means that virtually every environment that can be colonized by life has been explored and populated by plants. To achieve such amazing results while being unable to move from the site of seed germination, plants have evolved an arsenal of solutions that make them suitable for life in the most demanding and extreme conditions. In addition, it is well established that plants are able to show considerable plasticity in their morphology and physiology in response to variability within their environment and to survive extremely diverse environmental conditions and stresses (Fujita et al (2006)). Thus the mechanical properties of plants, the morphology of their structures and their characteristic movements represent a goldmine of solutions that, with appropriate investigation, could be used to obtain new design rules for advanced bioinspired systems and materials in countless applications. Meanwhile, advances in technology, partly related to the adoption of such bio-inspired approaches in design, are opening new opportunities for the application of bioinspired artefacts in biological research.

 

Smart solutions from the plant kingdom

Barbara Mazzolai and Stefano Mancuso 2013 Bioinspir. Biomim. 8 020301 http://dx.doi.org/10.1088/1748-3182/8/2/020301

 

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Consciousness: Watching your mind in action

One area in which we have made great progress is in discovering the physical or neural correlates of consciousness – what consciousness in the brain "looks like", you might say. One way to investigate this question is to see what changes when consciousness is reduced or absent, as happens when people are in a vegetative state, with no sign of awareness.

Brain scans show that such people usually have damage to the thalamus, a relay centre located smack-bang in the middle of the brain. Another common finding is damage to the connections between the thalamus and the prefrontal cortex, a region at the front of the brain, generally responsible for high-level complex thought.

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'Geography of Hate' maps racism and homophobia on Twitter

'Geography of Hate' maps racism and homophobia on Twitter | Papers | Scoop.it

Twitter, even more than many other social media tools, can feel disconnected from the real world. But a group of students and professors at research site Floating Sheep have built a comprehensive map of some of Twitter's most distasteful content: the racist, homophobic, or ableist slurs that can proliferate online. Called Geography of Hate, the interactive map charts ten relatively common slurs across the continental US, either by general category or individually. Looking at the whole country, you'll often see a mass of red or what the map's creators call a "blue smog of hate." Zooming in, however, patches appear over individual regions or cities; some may be predictable, while others are not.

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Controlled Flight of a Biologically Inspired, Insect-Scale Robot

Flies are among the most agile flying creatures on Earth. To mimic this aerial prowess in a similarly sized robot requires tiny, high-efficiency mechanical components that pose miniaturization challenges governed by force-scaling laws, suggesting unconventional solutions for propulsion, actuation, and manufacturing. To this end, we developed high-power-density piezoelectric flight muscles and a manufacturing methodology capable of rapidly prototyping articulated, flexure-based sub-millimeter mechanisms. We built an 80-milligram, insect-scale, flapping-wing robot modeled loosely on the morphology of flies. Using a modular approach to flight control that relies on limited information about the robot’s dynamics, we demonstrated tethered but unconstrained stable hovering and basic controlled flight maneuvers. The result validates a sufficient suite of innovations for achieving artificial, insect-like flight.

 

Controlled Flight of a Biologically Inspired, Insect-Scale Robot
Kevin Y. Ma, Pakpong Chirarattananon, Sawyer B. Fuller, Robert J. Wood

Science 3 May 2013:
Vol. 340 no. 6132 pp. 603-607
http://dx.doi.org/10.1126/science.1231806

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Cosmological natural selection and the purpose of the universe

The cosmological natural selection (CNS) hypothesis holds that the fundamental constants of nature have been fine-tuned by an evolutionary process in which universes produce daughter universes via the formation of black holes. Here, we formulate the CNS hypothesis using standard mathematical tools of evolutionary biology. Specifically, we capture the dynamics of CNS using Price's equation, and we capture the adaptive purpose of the universe using an optimization program. We establish mathematical correspondences between the dynamics and optimization formalisms, confirming that CNS acts according to a formal design objective, with successive generations of universes appearing designed to produce black holes.

 

Cosmological natural selection and the purpose of the universe

Andy Gardner, Joseph P. Conlon

Complexity, Early View

http://dx.doi.org/10.1002/cplx.21446

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Harshal Hayatnagarkar's curator insight, May 10, 2013 8:52 AM

I

Arjen ten Have's curator insight, May 23, 2013 7:52 AM

This ought to be interesting, but look at that. It is the other way around. It is not a law of physics that rules biology. It is a biological theory that governs physics?? Or is it?

The principle of evolution by selection is that strong (and clear, except for when you are an IDiot) that it applies to everything. Natural selection is like the rule that rules it all. It is      GOD!

I have to read this but for sure can say that the Universe has no purpose.

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Exploration versus exploitation in polydomous ant colonies

In socially foraging species resource information can be shared between individuals, increasing foraging success. In ant colonies, nestmate recruitment allows high exploitation rates at known resources however, to maximise foraging efficiency this must be balanced with searching for new resources.

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Evolutionary game based control for biological systems with applications in drug delivery

Evolutionary game based control for biological systems with applications in drug delivery | Papers | Scoop.it

This paper proposes a control framework for biological systems subject to dynamics that exhibit adaptive behavior under evolutionary pressures. The control framework was formulated based on evolutionary game based modeling, which integrates both the internal dynamics and the population dynamics.

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A review on agent-based technology for traffic and transportation

In the last few years, the number of papers devoted to applications of agent-based technologies to traffic and transportation engineering has grown enormously. Thus, it seems to be the appropriate time to shed light over the achievements of the last decade, on the questions that have been successfully addressed, as well as on remaining challenging issues. In the present paper, we review the literature related to the areas of agent-based traffic modelling and simulation, and agent-based traffic control and management. Later we discuss and summarize the main achievements and the challenges.

 

A review on agent-based technology for traffic and transportation
Ana L. C. Bazzan and Franziska Klügl

The Knowledge Engineering Review

http://dx.doi.org/10.1017/S0269888913000118

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More Power from Below

Geothermal heat provides sustainable energy for electricity generation and heating applications. Worldwide use of geothermal energy has increased steadily over the past few decades (1, 2), and exploration and development are ongoing at unprecedented levels in Iceland, New Zealand, East Africa, Germany, Chile, and Australia. Today, 24 countries generate electricity from geothermal energy and 78 countries use geothermal energy for direct uses. Yet, geothermal sources still represent less than one percent of global energy production. The accessibility of geothermal resources depends on temperature and depth (see the figure). What are the limitations of geothermal energy extraction, and can the use of this resource be increased?

 

More Power from Below
Joseph N. Moore, Stuart F. Simmons

Science 24 May 2013:
Vol. 340 no. 6135 pp. 933-934
http://dx.doi.org/10.1126/science.1235640

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Whatever next? Predictive brains, situated agents, and the future of cognitive science

Brains, it has recently been argued, are essentially prediction machines. They are bundles of cells that support perception and action by constantly attempting to match incoming sensory inputs with top-down expectations or predictions. This is achieved using a hierarchical generative model that aims to minimize prediction error within a bidirectional cascade of cortical processing. Such accounts offer a unifying model of perception and action, illuminate the functional role of attention, and may neatly capture the special contribution of cortical processing to adaptive success. This target article critically examines this “hierarchical prediction machine” approach, concluding that it offers the best clue yet to the shape of a unified science of mind and action.

 

Whatever next? Predictive brains, situated agents, and the future of cognitive science
Andy Clark

Behavioral and Brain Sciences / Volume 36 / Issue 03 / June 2013, pp 181-204

http://dx.doi.org/10.1017/S0140525X12000477

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Harshal Hayatnagarkar's comment, May 21, 2013 9:37 PM
Singularity is near !
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Exploiting ecological principles to better understand cancer progression and treatment

A small but growing number of people are finding interesting parallels between ecosystems as studied by ecologists (think of a Savanna or the Amazon rain forest or a Coral reef) and tumours1-3. The idea of viewing cancer from an ecological perspective has many implications but fundamentally, it means that we should not see cancer just as a group of mutated cells. A more useful definition of cancer is to consider it a disruption in the complex balance of many interacting cellular and microenvironmental elements in a specific organ. This perspective means that organs undergoing carcinogenesis should be seen as sophisticated ecosystems in homeostasis that cancer cells can disrupt. It also makes cancer seem even more complex but may ultimately provides isights that make it more treatable. Here we discuss how ecological principles can be used to better understand cancer progression and treatment, using several mathematical and computational models to illustrate our argument.

 

Exploiting ecological principles to better understand cancer progression and treatment

David Basanta, Alexander R. A. Anderson

http://arxiv.org/abs/1305.2249

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Self-organization of progress across the century of physics

We make use of information provided in the titles and abstracts of over half a million publications that were published by the American Physical Society during the past 119 years. By identifying all unique words and phrases and determining their monthly usage patterns, we obtain quantifiable insights into the trends of physics discovery from the end of the 19th century to today. We show that the magnitudes of upward and downward trends yield heavy-tailed distributions, and that their emergence is due to the Matthew effect. This indicates that both the rise and fall of scientific paradigms is driven by robust principles of self-organization. Data also confirm that periods of war decelerate scientific progress, and that the later is very much subject to globalization.

 

Self-organization of progress across the century of physics

Matjaz Perc

http://arxiv.org/abs/1305.0552

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The Future of Green Building May Be Closer than You Think

The Future of Green Building May Be Closer than You Think | Papers | Scoop.it

Buildings that consume no outside energy are being developed today -- with existing technology. So much innovative work has been done in green building that a growing number of people are now shifting their focus from means to ends. Their goal: Create buildings that generate as much energy as they need to operate, called net-zero energy buildings (NZEB). Efforts to achieve NZEB are underway in all sectors -- government, academia, the military, not-for-profits and business -- and at all scales: residential, community and commercial. While it is still early days, the results have been impressive.
http://knowledge.wharton.upenn.edu/article.cfm?articleid=3247

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On Creativity of Elementary Cellular Automata

We map cell-state transition rules of elementary cellular automata (ECA) onto the cognitive control versus schizotypy spectrum phase space and interpret cellular automaton behaviour in terms of creativity. To implement the mapping we draw analogies between a degree of schizotypy and generative diversity of ECA rules, and between cognitive control and robustness of ECA rules (expressed via Derrida coefficient). We found that null and fixed point ECA rules lie in the autistic domain and chaotic rules are 'schizophrenic'. There are no highly articulated 'creative' ECA rules. Rules closest to 'creativity' domains are two-cycle rules exhibiting wave-like patterns in the space-time evolution.

 

On Creativity of Elementary Cellular Automata

Andrew Adamatzky, Andrew Wuensche

http://arxiv.org/abs/1305.2537

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Global computational intelligence

Global computational intelligence | Papers | Scoop.it

So what would it mean for us?

For a person – start feeling as part of the whole body or real-time sensor/motor cell of entire humanity organism, with every your search query, email, chat message or mouse click making it a bit more clever and strong, and every your action to some extent inspired by it.

For software developers – get ready for emerging market of intellectual agent software (with first lonely players like Siri, Google Now and Sherpa), either keeping in mind business model of a «pilot fish», operating in biocenosis with one of the «Big Sharks» or having a good exit strategy for the case when your functionality may get on the way of some of major players (like it has happened to Yandex Wonder).

For business – for competitive business promotion, understand how to craft «double-sided» web pages looking attractive for fellow people on one side and rich of true semantic markup on the other side. That kind of markup, invisible to human eye (see http://schema.org/ for more details) is to be indexed by «semantic crawler» at Google, collecting the thought-food for its Knowledge Graph — so that your site could get returned to user as single right answer on user's query, instead of being on 10th row of second page of search results.

For government – be clear that ability to enable national projects of intellectual globalization might turn into a key for national security in the very close future. That does not necessarily mean any governmental funding of certain developments, as we have seen couple business enterprises managed to capture the third of the world in few years, so the most efficient option would be creation of appropriate business environments for high technology and information technology businesses within national borders.

For humanity – get ready to pass through the next (since invention of computers and internet) pivotal point of development, with all coming surprises, frustrations and openings of new opportunities.

For evolution – prepare to record forthcoming meta-system transition (since assembly of atoms in the molecule, molecules in the cell, cells into organism and neurons in the brain) in the Universe's diary book.

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Luciano Lampi's curator insight, May 17, 2013 3:51 AM

Endless complexity!

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Employment Growth through Labor Flow Networks

Employment Growth through Labor Flow Networks | Papers | Scoop.it

It is conventional in labor economics to treat all workers who are seeking new jobs as belonging to a labor pool, and all firms that have job vacancies as an employer pool, and then match workers to jobs. Here we develop a new approach to study labor and firm dynamics. By combining the emerging science of networks with newly available employment micro-data, comprehensive at the level of whole countries, we are able to broadly characterize the process through which workers move between firms. Specifically, for each firm in an economy as a node in a graph, we draw edges between firms if a worker has migrated between them, possibly with a spell of unemployment in between. An economy's overall graph of firm-worker interactions is an object we call the labor flow network (LFN). This is the first study that characterizes a LFN for an entire economy. We explore the properties of this network, including its topology, its community structure, and its relationship to economic variables. It is shown that LFNs can be useful in identifying firms with high growth potential. We relate LFNs to other notions of high performance firms. Specifically, it is shown that fewer than 10% of firms account for nearly 90% of all employment growth. We conclude with a model in which empirically-salient LFNs emerge from the interaction of heterogeneous adaptive agents in a decentralized labor market.

 

Guerrero OA, Axtell RL (2013) Employment Growth through Labor Flow Networks. PLoS ONE 8(5): e60808. http://dx.doi.org/10.1371/journal.pone.0060808

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Recombinatorial Logic

Logic gates evoke images of circuit boards, but cells are arguably equally good in relying on logic computations. A classic example is the Lac operon, which activates itself upon the condition “lactose AND NOT glucose” (1). In recent years, there have been multiple reports on rationally designed, genetically encoded logic gates and circuits in living cells (2). Just like the Lac operon, these gates receive two or more molecular signals (inputs) and generate a product (output) whose level is logically linked to the inputs. Sixteen different logic connections are possible with two inputs and one output, but many of these operations have remained refractory to rational design. The trickiest of these gates usually make general statements about the inputs without referring to their exact values, such as “both inputs are the same” (an XNOR gate) or “two inputs are different” (an XOR gate). Two studies, one on page 599 of this issue by Bonnet et al. (3) and one by Siuti et al. (4), describe approaches that produce any of the 16 gates, including the notorious XNOR and XOR, in a compact manner by making relatively minor tweaks to the gates' genetic building blocks.

 

Recombinatorial Logic
Yaakov Benenson

Science 3 May 2013:
Vol. 340 no. 6132 pp. 554-555
http://dx.doi.org/10.1126/science.1237738

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Modeling Practices in the Social and Human Sciences. An Interdisciplinary Exchange

The study of scientific models has become an active and important focus in history and philosophy of science, and to a lesser extent in sociology of science. Such attention acknowledges that models are central to scientific practice and that they are distinct from both theory and data, but there is a growing realization that modeling practices differ between and within disciplines. This special issue uses this realization to extend the discussion on models into new areas and different uses in the human and social sciences.

 


Modeling Practices in the Social and Human Sciences. An Interdisciplinary Exchange
Mary S. Morgan and Till Grüne-Yanoff
Perspectives on Science Summer 2013, Vol. 21, No. 2, Summer 2013: 143-156.

http://dx.doi.org/10.1162/POSC_a_00089

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Task-partitioning in insect societies: Non-random direct material transfers affect both colony efficiency and information flow

Task-partitioning is an important organisational principle in insect colonies and is thought to increase colony efficiency. In task-partitioning, tasks such as the collection of resources are divided into subtasks in which the material is passed from one worker to another. We used an agent-based simulation model to explore how non-random interactions during task-partitioning with direct transfer affect colony work efficiency.

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Overpunishing is not necessary to fix cooperation in voluntary public goods games

The fixation of cooperation among unrelated individuals is one of the fundamental problems in biology and social sciences. It is investigated by means of public goods games, the generalization of the prisoner's dilemma to more than two players. In compulsory public goods games, defect is the dominant strategy, while voluntary participation overcomes the social dilemma by allowing a cyclic coexistence of cooperators, defectors, and non-participants. [...] a milder punishing mechanism, where defectors only risk a fixed penalty per round—as in many real situations—and the cost of punishment is shared among the punishers. The payoffs for the four strategies—cooperate, defect, abstain, and cooperate-&-punish—are derived and the corresponding replicator dynamics analyzed in full detail.

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