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"The concept of the cosmic web-viewing the universe as a set of discrete galaxies held together by gravity-is deeply ingrained in cosmology. Yet, little is known about architecture of this network or its characteristics. Our research used data from 24,000 galaxies to construct multiple models of the cosmic web, offering complex blueprints for how galaxies fit together. These three interactive visualizations help us imagine the cosmic web, show us differences between the models, and give us insight into the fundamental structure of the universe."

This is the first time that significant pair production has been demonstrated in a structure that can be electrically self-pumped and which can form the basis for passive optical circuitry, bringing us markedly closer to complete integration of quantum optical technologies.

our next gadget? fully open source it seems

Something for our Nano structure fans. Funniest remark: "One of the researchers got to take advantage of his Russian language skills since some of the chemistry details necessary for understanding the reaction mechanism was only available in an old Russian PhD thesis."

"When a control laser is fired at the crystal, a complex quantum-level reaction turns it the opaque crystal transparent. A second light source is beamed into the crystal before the control laser is shut off, returning the crystal to its opaque state. This leaves the light trapped inside the crystal, and the opacity of the crystal keeps the light trapped inside from bouncing around, effectively bringing light to a full stop." is the simple explanation, but I am not sure how this is actually possible with the current laws of physics

There are two ways to make slow light: material slow light and structural slow light, where you either change the material or the structural properties of your system. Here they used EIT to make material slow light, by inducing transparency inside an otherwise opaque material. As you change the absorption properties of a material you also change its dispersion properties, the so-called Kramers-Kronig relations. A rapid positive change in the dispersion properties of a material will give rise to slow light. To effectively stop light they switched off the control beam, bringing back the opaque state. Another control beam is then used to retrieve the probe pulse that was 'frozen' inside the medium. Light will be halted according to the population lifetime on the energy level (~ 100s). They used an evolutionary algorithm to find an optimal pulse preparation sequence to reach close to the maximum possible storage duration of 100s. Interesting paper!

So it is not real storage then in a sense, as you are stimulating an excitation population which retains the phase information of your original pulse? Still it is amazing that they could store this up to 100s and retrieve it with a probe pulse, but light has never been halted.

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

Using the angular momentum transmitted by an internal flywheel as an impulse, these cubes can move, jump, roll across the ground and climb over and around one another. They stick together using a set of small magnets, smart !

That is indeed a great way of using modular robots to build larger structures. I think we did bump into this some time back, but never really considered it much. Considering now the working group on structure assembling, I think we should add it to the list of building strategies and seriously consider it.

New 3D printed macro structure exhibits selective buckling open the way for custom shape-memory materials found our neighbor scientists from the Lorentz Institut of the Leiden University. Wonder if it can be applied for self-assembled deployment of structures.

"We fit data to zonal interaction models and characterize which individual interaction forces suffice to explain observed spatial patterns." You can get the paper from the first author's website: http://people.stfx.ca/rlukeman/research.htm

PNAS? Didnt strike me as sth very new though... We should refer to it in the roots study though: "Social organisms form striking aggregation patterns, displaying cohesion, polarization, and collective intelligence. Determining how they do so in nature is challenging; a plethora of simulation studies displaying life-like swarm behavior lack rigorous comparison with actual data because collecting field data of sufficient quality has been a bottleneck." For roots it is NO bottleneck :) Tobias was right :)

Here they assume all relevant variables influencing behaviour are being observed. Namely, the relative positions and orientations of all ducks in the swarm. So, they make movies of the swarm's movements, process them, and them fit the models to that data. In the roots, though we can observe the complete final structure, or even obtain time-lapse movies showing how that structure came out to be, getting the measurements of all relevant soil variables (nitrogen, phosphorus, ...) throughout the soil, and over time, would be extremely difficult. So I guess a replication of the kind of work they did, but for the roots, would be hard. Nice reference though.

wow ....

impressive! I'm sure it's connected to the black hole, at some point it must have been active. It shows how it's important to put all observations public !

this is what they speculate ... the original image looks though much less impressive ...

some ideas for movie Fridays A "must" see on my opinion (never heard about it in the past!) : Primer Sounds ideal: "Primer is a 2004 American science fiction film about the accidental discovery of time travel. The film was written, directed and produced by Shane Carruth, a mathematician and a former engineer, and was completed on a budget of $7,000.[1] Primer is of note for its extremely low budget, experimental plot structure and complex technical dialogue, which Carruth chose not to 'dumb down' for the sake of his audience. One reviewer said that "anybody who claims [to] fully understand what's going on in Primer after seeing it just once is either a savant or a liar."[2] The film collected the Grand Jury Prize at Sundance in 2004 before securing a limited release in US cinemas, and has since gained a cult following."

I watched it a while ago during my studies in Belgium... The plot is quite well summarized on this diagram: http://xkcd.com/657/large/ According to the text above I'm either savant or a liar (you choose). But I watched the movie under significant exposure to Belgian beer, so this may have helped...

Here, we report new materials and mechanical design principles of the iron-plated multilayered structure of the natural armor of Crysomallon squamiferum, a recently discovered gastropod mollusc from the Kairei Indian hydrothermal vent field, which is unlike any other known natural or synthetic engineered armor.

bit confused about what they actually have achieved so far but sounds like it might turn out to be interesting. "The scientists first infiltrated the leaves of Anemone vitifolia -- a plant native to China -- with titanium dioxide in a two-step process. Using advanced spectroscopic techniques, the scientists were then able to confirm that the structural features in the leaf favorable for light harvesting were replicated in the new TiO2 structure. Excitingly, the AIL are eight times more active for hydrogen production than TiO2 that has not been "biotemplated" in that fashion. AILs also are more than three times as active as commercial photo-catalysts. Next, the scientists embedded nanoparticles of platinum into the leaf surface. Platinum, along with the nitrogen found naturally in the leaf, helps increase the activity of the artificial leaves by an additional factor of ten."

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cool. It would be very to make a review of interesting photonic properties we could benefit from nature, and the possible use for space. It's nice to see that some structured can already be replicated...! Is there a structure to give angulaer momentum to light ?

This is about biological and technical hygromorphs, i.e. structures that change shape according to humidity. Next to pine cones, there is also a cool study on wheat awns which drill themselves into the soil just by daily variance of air humidity. Biomimetics would be passively controlled acutators or humidity driven valves in space station to open/close dehumidification devices.

Interesting, but only an abstract... do you have the full paper ?

Not yet. There is also some other nice mechanism of wheat awns and how they use changes in humidity to anchor in soil. Would maybe fit with the above mentioned work of oisin.

On the basis of molecular dynamics simulations, we propose a design for a molecular water pump. The design uses a combination of charges positioned adjacent to a nanopore and is inspired by the structure of channels in the cellular membrane that conduct w

Intelligent Material Systems and Structures (Virginia)

We find that the high thermal conductivity of carbon nanotubes remains intact under severe structural deformations while the corresponding electrical resistance and thermoelectric power show compromised responses. Similar robust thermal transport against