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Taking decisions - how monkeys do it http://www.nature.com/nature/journal/v447/n7148/pdf/nature05852.pdf

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

Almost in time for the workshop last week! This new Nature paper (e-mail me for full paper) claims training and usage of neural network implemented with metal-oxide memristors, without selector CMOS. They used it to implement a delta-rule algorithm for classification of 3x3 pixel black and white letters. Very impressive work!!!!

For those not that much into the topic, see the Nature's News and View section www.nature.com/nature/journal/v521/n7550/full/521037a.html?WT.ec_id=NATURE-20150507 where they feature this article.

Here is a probably definite answer to the strong polemics around the test of gravitational redshift with atom interferometers, which would be far better than the one done by ACES/PHARAO. Read the abstract it's very ACT like, Luzi should like it :) The original Nature paper is the one of Muller, Peters and Chu (the nobel and secretary of energy in the US): http://www.nature.com/nature/journal/v463/n7283/full/nature08776.html

is this really worth a nature paper??

Funny to read this question exactly from you, the all and ever fan of anything linked to bio :-) I have read worse papers in nature and in addition it's just "Nature physics", viz. "Nature garbage." Could be that they don't find enough really good stuff to publish in all their topical clones of Nature.

francesco already posted this below

Sounds too super to be true, no?

> Sounds too super to be true, no? Yeah, how else may it sound, being a combination of hi-quality (I assume) research targeted at attracting funding, raised to the power of Science Daily's pop-pseudo-scientific journalists' bu****it? Original article starts with a cool sentence too: > The ultimate proof of our understanding of natural or technological systems is reflected in our ability to control them. ...a good starting point for a never-ending philosophers' debate... Now seriously, because of a big name behind the study, I'm very curious to read the original article. Although I expect the conclusion to be that in practical cases (i.e. the cases of "networks" you *would like to* "control"), you need to control all nodes or something equally impractical...

then I am looking forward to reading your conclusions here after you will have actually read the paper

Sorry ,here now the right link to the nature paper ...in english

Progress in atomic, optical and quantum science1, 2 has led to rapid improvements in atomic clocks. At the same time, atomic clock research has helped to advance the frontiers of science, affecting both fundamental and applied research. The ability to control quantum states of individual atoms and photons is central to quantum information science and precision measurement, and optical clocks based on single ions have achieved the lowest systematic uncertainty of any frequency standard3, 4, 5. Although many-atom lattice clocks have shown advantages in measurement precision over trapped-ion clocks6, 7, their accuracy has remained 16 times worse8, 9, 10. Here we demonstrate a many-atom system that achieves an accuracy of 6.4 × 10−18, which is not only better than a single-ion-based clock, but also reduces the required measurement time by two orders of magnitude. By systematically evaluating all known sources of uncertainty, including in situ monitoring of the blackbody radiation environment, we improve the accuracy of optical lattice clocks by a factor of 22. This single clock has simultaneously achieved the best known performance in the key characteristics necessary for consideration as a primary standard-stability and accuracy. More stable and accurate atomic clocks will benefit a wide range of fields, such as the realization and distribution of SI units11, the search for time variation of fundamental constants12, clock-based geodesy13 and other precision tests of the fundamental laws of nature. This work also connects to the development of quantum sensors and many-body quantum state engineering14 (such as spin squeezing) to advance measurement precision beyond the standard quantum limit.

very nice nature paper ... the title says it all ...

...This slippery surface was bio-inspired by the carnivorous plant I showed you sometimes ago! I was sure it was a good idea! next time I will be quicker!!

And a good lesson that it is important to proceed quickly when you have an idea and don't wait ...

Yes, I will see what we could do, but they really did a good job, from the biomimetic of the surface, up to the realization of the material, and the tests...

In a work published on Nature (http://www.nature.com/nature/journal/v517/n7536/full/nature14090.html#affil-auth) a new DFT based simulation of convection in Earth's Core iron shows that electron-electron scattering has a similar contribution to electron's thermal vibration. The outcome is that using the old dynamo theory the simulation matches the Earth magnetic field experimental results, solving an 80 years old puzzle.

Yay to science! I'm always intrigued by related experiments that try to measure material properties at the GPa range. Especially, the efforts of reaching 'metallic hydrogen' (http://en.wikipedia.org/wiki/Metallic_hydrogen), requiring pressures above 25GPa at which hydrogen becomes conductive. It is thought that gas giant planets could have such a core, but no-one has been able to produce/verify this theory as off yet.

once more ... the Romans did it already 2000 years ago! this time: burning so much wood that they increased the methane level in a way we can still measure it in ice cores ...

The ALPHA collaboration reports the first ever measurement on the optical spectrum of an antimatter hydrogen atom. Optical transitions shown to be the same as for normal hydrogen. Paper at http://www.nature.com/nature/journal/vaap/ncurrent/full/nature21040.html#affil-auth

Look at this! Seems that we are as close to the bonobos as we are to the chimpanzees If only we resolved more to their ways of getting rid of stress (sex) more than using the chimpanzees' (aggression)...

theoretical physicists... :) Read the last sentence of the paper...in this way anyone can publish in nature...just make a good story with little evidence Did dark matter kill the dinosaurs? The Solar System's periodic passage through a 'dark disk' on the galactic plane could trigger comet bombardments that would cause mass extinctions.

Hmm.. right.. then again, this is not an actual journal publication but a news broadcast. But you are right that the name Nature is attached to it so the journal is definitely banking on their acquired status.

A possible way of teraforming some planets or moons?

Here we go: we might not need liquid water after all on mars to get some nice flowering plants there! ... and terraform ? :-) Thirsty plants can extract water from the crystalline structure of gypsum, a rock-forming mineral found in soil on Earth and Mars.

Some plants grow on gypsum outcrops and remain active even during dry summer months, despite having shallow roots that cannot reach the water table. Sara Palacio of the Pyrenean Institute of Ecology in Jaca, Spain, and her colleagues compared the isotopic composition of sap from one such plant, called Helianthemum squamatum (pictured), with gypsum crystallization water and water found free in the soil. The team found that up to 90% of the plant's summer water supply came from gypsum.

The study has implications for the search for life in extreme environments on this planet and others.

Nature Commun 5, 4660 (2014)

Very interesting indeed. Attention is to be put on the form of calcium sulfate that is found on Mars. If it is hydrated (gypsum Ca(SO4)*2(H2O)) it works, but if it is dehydrated there is no water for the roots to take in. The Curiosity Rover tries to find out, but has uncertainty in recognising the hydrogen presence in the mineral: Copying : "(...) 3.2 Hydration state of calcium sulfates Calcium sulfates occur as a non-hydrated phase (anhydrite, CaSO4) or as one of two hydrated phases (bassanite, CaSO4.1/2H2O, which can contain a somewhat variable water content, and gypsum, CaSO4.2H2O). ChemCam identifies the presence of hydrogen at 656 nm, as already found in soils and dust [Meslin et al., 2013] and within fluvial conglomerates [Williams et al., 2013]. However, the quantification of H is strongly affected by matrix effects [Schröder et al., 2013], i.e. effects including major or even minor element chemistry, optical and mechanical properties, that can result in variations of emission lines unrelated to actual quantitative variations of the element in question in the sample. Due to these effects, discriminating between bassanite and gypsum is difficult. (...)"

forgot the reference http://www.msl-chemcam.com/doc/documents/577/Nachon%20et%20al%20Calcium%20sulfate%20veins%20characterized%20by%20ChemCam%20Curiosity%20at%20Gale%20Crater%20Mars_2013.pdf

one more step in the right direction for thermoelectrics ...

interesting power source ...