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Very interesting presentation on how the brain can back-propagate error signals during learning (using time-derivatives to encode errors). Hinton discusses how back-propagation can be achieved with very limited / unsophisticated tools and in excessively noise environments.

Materials exposed to a high-radiation environment such as the inside of a nuclear reactor vessel can gradually degrade and weaken. A new approach to allow assessment of radiation damage in materials, on real time!

Finding penguin poo from space ....

news from the Sabre engine ...

Taking a look at some of the plants that push the boundaries in the botanical world.

Would be nice to also push for other alternative fuel and biofuel like the ones studied at Glenn Research Center for airacraft gas turbines (Fischer Tropsch Fuel instead of JP-8) and presented an the International Workshop on Environment and Alternative Energy at ESTEC

smart move ...

A new discovery from a chemist at the University of Texas at Austin may allow photovoltaic solar cells to double their efficiency, thus providing loads more electrical power from regular sunlight.

hey! This is essentially the Probabilistic Computing Ariadna

The link is there but my understanding of our purpose is different than what I understood from the abstract. In any case,the authors are from Palma de Mallorca, Balears, Spain "somebody" should somehow make them aware of the Ariadna study ... E.g somebody no longer in the team :-)

The work of our team on the Mimosa Pudica has been publish! It proves for the first time the ability of plants to learn. After a countless number of rejections, Oecologia had the courage of publishing it. Now the road is open to demonstrations that learning capability exists not only in sensitive plants, but also in normal plants. This can change the entire biology. A bit rhetorical, but real.

very nice!!! congratulations! what are you working on now - also on this?

I work on some aspects of plant to plant communication! I hope to publish soon something equally exciting!! and of course I will let you know!!

Weird.

This reminds me a 2013 paper on how to perform derivatives, integrals and even time reversal in optical fibres: http://www.nature.com/srep/2013/130403/srep01594/full/srep01594.html "The manipulation of dynamic Brillouin gratings in optical fibers is demonstrated to be an extremely flexible technique to achieve, with a single experimental setup, several all-optical signal processing functions. In particular, all-optical time differentiation, time integration and true time reversal are theoretically predicted, and then numerically and experimentally demonstrated."

Would this kind of computer be more space environment resistive?

Sounds relevant. Does ESA need to have a position on this question?

This was on Slashdot now, with a link to the paper. It quite an iteresting study actually. "The scenarios most closely reflecting the reality of our world today are found in the third group of experiments (see section 5.3), where we introduced economic stratification. Under such conditions, we find that collapse is difficult to avoid."

Interesting, but is it new? In general, I would say that history has shown us that it is inevitable that civilisations get replaced by new concepts (much is published about this, read eg Fog of War by Jona Lendering on the struggles between civilisations in ancient history, which have remarkably similar issues as today, yet on a different scale of course). "While some members of society might raise the alarm that the system is moving towards an impending collapse and therefore advocate structural changes to society in order to avoid it, Elites and their supporters, who opposed making these changes, could point to the long sustainable trajectory 'so far' in support of doing nothing." I guess this bang on it, the ones that can change the system, are not benefitted by doing so, hence enrichment, depletion, short term gain remain and might even accelerate to compensate for the loss in the rest of the system.

The underground lake is big enough to cover Kenia's water need for the next 70 years

"Horsetail plant spores use 'legs' to walk and jump!"

Another underestimated source of CO2, are turbulent waters. "The stronger the turbulences at the water's surface, the more CO2 is released into the atmosphere. The combination of maps and data revealed that, while the CO2 emissions from lakes and reservoirs are lower than assumed, those from rivers and streams are three times as high as previously believed." Alltogether the emitted CO2 equates to roughly one-fifth of the emissions caused by humans. Yet more stuff to model...

Nasia, I thought about your statement carefully - and I cannot agree with you. Water is not a greenhouse gas. It is instead a liquid. Also, I can't believe you keep feeding the troll! :-P But on a more topical note: I think it is an over-simplification to call water a greenhouse gas - water is one of the most important mechanisms in the way Earth handles heat input from the sun. The latent heat that you mention actually cools Earth: solar energy that would otherwise heat Earth's surface is ABSORBED as latent heat by water which consequently evaporates - the same water condenses into rain drops at high altitudes and releases this stored heat. In effect the water cycle is a mechanism of heat transport from low altitude to high altitude where the chance of infrared radiation escaping into space is much higher due to the much thinner layer of atmosphere above (including the smaller abundance of greenhouse gasses). Also, as I know you are well aware, the cloud cover that results from water condensation in the troposphere dramatically increases albedo which has a cooling effect on climate. Furthermore the heat capacity of wet air ("humid heat") is much larger than that of dry air - so any advective heat transfer due to air currents is more efficient in wet air - transporting heat from warm areas to a natural heat sink e.g. polar regions. Of course there are also climate heating effects of water like the absorption of IR radiation. But I stand by my statement (as defended in the above) that rain cools the atmosphere. Oh and also some nice reading material on the complexities related to climate feedback due to sea surface temperature: http://journals.ametsoc.org/doi/abs/10.1175/1520-0442(1993)006%3C2049%3ALSEOTR%3E2.0.CO%3B2

I enjoy trolling conversations when there is a gain for both sides at the end :-) . I had to check upon some of the facts in order to explain my self properly. The IPCC report states the greenhouse gases here, and water vapour is included: http://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-2-1.html Honestly, I read only the abstract of the article you posted, which is a very interesting hypothesis on the mechanism of regulating sea surface temperature, but it is very localized to the tropics (vivid convection, storms) a region of which I have very little expertise, and is difficult to study because it has non-hydrostatic dynamics. The only thing I can comment there is that the authors define constant relative humidity for the bottom layer, supplied by the oceanic surface, which limits the implementation of the concept on other earth regions. Also, we may confuse during the conversation the greenhouse gas with the Radiative Forcing of each greenhouse gas: I see your point of the latent heat trapped in the water vapour, and I agree, but the effect of the water is that it traps even as latent heat an amount of LR that would otherwise escape back to space. That is the greenhouse gas identity and an image to see the absorption bands in the atmosphere and how important the water is, without vain authority-based arguments that miss the explanation in the end: http://www.google.nl/imgres?imgurl=http://www.solarchords.com/uploaded/82/87-33833-450015_44absorbspec.gif&imgrefurl=http://www.solarchords.com/agw-science/4/greenhouse--1-radiation/33784/&h=468&w=458&sz=28&tbnid=x2NtfKh5OPM7lM:&tbnh=98&tbnw=96&zoom=1&usg=__KldteWbV19nVPbbsC4jsOgzCK6E=&docid=cMRZ9f22jbtYPM&sa=X&ei=SwynUq2TMqiS0QXVq4C4Aw&ved=0CDkQ9QEwAw

so it took us 70% of the time Earth is in the habitable zone to develop, would this be normal or could it be much faster? In other words, would all forms of life that started on a planet that originated at a 'similar' point in time like us, be equally far developed?

That is actually quite tricky to estimate rly. If for no other reason than the fact that all of the mass extinctions we had over the Earth's history basically reset the evolutionary clock. Assuming 2 Earths identical in every way but one did not have the dinosaur wipe-out impact, that would've given non-impact Earth 60million years to evolve a potential dinosaur intelligent super race.

The opposite might be true - or might not be ;-). Since usually the rate of evolution increases after major extinction events the chance is higher to produce 'intelligent' organisms if these events happen quite frequently. Usually the time of rapid evolution is only a few million years - so Earth is going quite slow. Certainly extinction events don't reset the evolutionary clock - if they would never have happened Earth gene pool would probably be quite primitive. By the way: dinosaurs were a quite diverse group and large dinosaurs might well have had cognitive abilities that come close to whales or primates - the difference to us might be that we have hands to manipulate our environment and vocal cords to communicate in very diverse ways. Modern dinosaur (descendents), i.e. birds, contain some very intelligent species - especially with respect to their body size and weight.