Group items tagged

As the researchers desribe, the aquifer found is defined as a basin filled with aged snow (firn) that was saturated with water trapped within its porous structure. More ice cores to study! But in that case the time sequence along the length of the cores - to be extracted- would not be monotonic, as was the case in the dry cores we analysed. That's because there is constant input of surface water percolating through the ice-sheet to reach the depth of the aquifer, and since it flows downward its temperature could affect its partial pressure => its vertical position along the core

Lockheed Martin Corp said on Wednesday it had made a technological breakthrough in developing a power source based on nuclear fusion, and the first reactors, small enough to fit on the back of a truck, could be ready in a decade.

Is positive news definitely, but when it comes to fusion energy being skeptic is the wisest course of action. On the back of a truck basically means that the energy density of the device is such that the surface energy of a (steady state) plasma is beyond currents materials limits. It is probably a pulsed (ignitor-type) device, which are prone to instabilities. That could therefore refer to their breakthrough claim, of which they hardly say anything though. Lets see

Since there were already a lot of false alarms on the field, one should definitively be careful about it. However not a single detail about its structure or how it works in this new... Here http://www.fusenet.eu/node/400 you can find a bit more of information about it.

Jeremy England, a 31-year-old assistant professor at the Massachusetts Institute of Technology, has derived a mathematical formula that he believes explains this capacity. The formula, based on established physics, indicates that when a group of atoms is driven by an external source of energy (like the sun or chemical fuel) and surrounded by a heat bath (like the ocean or atmosphere), it will often gradually restructure itself in order to dissipate increasingly more energy. This could mean that under certain conditions, matter inexorably acquires the key physical attribute associated with life. The simulation results made me think of Jojo's attempts to make a self-assembling space structure. Seems he may have been on the right track, just not thinking big enough

:-P Thanks Thijs... I do not agree with the premise of the article that a possible correlation of energy dissipation in living systems and their fitness means that one is the cause for the other - it may just be that both go hand-in-hand because of the nature of the world that we live in. Maybe there is such a drive for pre-biotic systems (like crystals and amino acids), but once life as we know it exists (i.e., heredity + mutation) it is hard to see the need for an amendment of Darwin's principles. The following just misses the essence of Darwin: "If England's approach stands up to more testing, it could further liberate biologists from seeking a Darwinian explanation for every adaptation and allow them to think more generally in terms of dissipation-driven organization. They might find, for example, that "the reason that an organism shows characteristic X rather than Y may not be because X is more fit than Y, but because physical constraints make it easier for X to evolve than for Y to evolve." Darwin's principle in its simplest expression just says that if a genome is more effective at reproducing it is more likely to dominate the next generation. The beauty of it is that there is NO need for a steering mechanism (like maximize energy dissipation) any random set of mutations will still lead to an increase of reproductive effectiveness. BTW: what does "better at dissipating energy" even mean? If I run around all the time I will have more babies? Most species that prove to be very successful end up being very good at conserving energy: trees, turtles, worms. Even complexity of an organism is not a recipe for evolutionary success: jellyfish have been successful for hundreds of millions of years while polar bears are seem to be on the way out.

In essence, the idea involves building a skeleton structure, wrapping it with elastic materials and then start filling it with concrete. A technique first tried in the 60's but now evaluated again with renewed interest as low-cost option for housing.

sort of reminds me of this thing: https://www.youtube.com/watch?v=Vb1pdvvoVoQ

There is this optical neuron that gets stimulated from motion. Mapping it is difficult in the lab: "The stumbling block is a lack of fine-grained anatomical detail about how the neurons in the retina are wired up to each other." So, use people deciphering from 2D images --> the 3D neuron structure using the human spatial reasoning to figure out what is part of a branching cell and what is just background noise in the images (yet incomparable to their best algorithms' performance) 120.000 users so far mapped 2% of the retina

"Tilted table", "peacock" and "triple-floor building" are just three of many fantastical 3D structures that have been created by compressing simple 2D patterns. The new technique for creating these objects is called compressive buckling, and has been developed by researchers in the US, China and South Korea.

Researchers have proposed a new "acoustic topological insulator" that could help alleviate sound scattering problems by transmitting sound in certain directions without any backscattering.

If I understood correctly the triangular structure would channel the incident sound wave to a unique direction between two options, according to the rotation direction of the cylinders included in its mesh. So, one (possibly two) directions left to detect the hypothetical submarines? Very interesting though, I hope no oceanographers take measurements simultaneously to the signals as climate models will get even more wrong...!

Hundreds of hidden nearby galaxies have been studied for the first time, shedding light on a mysterious gravitational anomaly dubbed the Great Attractor. Despite being just 250 million light years from Earth-very close in astronomical terms-the new galaxies had been hidden from view until now by our own galaxy, the Milky Way. Using CSIRO's Parkes radio telescope equipped with an innovative receiver, an international team of scientists were able to see through the stars and dust of the Milky Way, into a previously unexplored region of space. The discovery may help to explain the Great Attractor region, which appears to be drawing the Milky Way and hundreds of thousands of other galaxies towards it with a gravitational force equivalent to a million billion Suns. Lead author Professor Lister Staveley-Smith, from The University of Western Australia node of the International Centre for Radio Astronomy Research (ICRAR), said the team found 883 galaxies, a third of which had never been seen before. "The Milky Way is very beautiful of course and it's very interesting to study our own galaxy but it completely blocks out the view of the more distant galaxies behind it," he said. Professor Staveley-Smith said scientists have been trying to get to the bottom of the mysterious Great Attractor since major deviations from universal expansion were first discovered in the 1970s and 1980s. "We don't actually understand what's causing this gravitational acceleration on the Milky Way or where it's coming from," he said. "We know that in this region there are a few very large collections of galaxies we call clusters or superclusters, and our whole Milky Way is moving towards them at more than two million kilometres per hour." The research identified several new structures that could help to explain the movement of the Milky Way, including three galaxy concentrations (named NW1, NW2 and NW3) and two new clusters (named CW1 and CW2).

Researchers from North Carolina State University have discovered a new phase of solid carbon, called Q-carbon, which is distinct from the known phases of graphite and diamond. They have also developed a technique for using Q-carbon to make diamond-related structures at room temperature and at ambient atmospheric pressure in air. It turns out this configuration is harder than diamond, plus the material has a very low work function. The latter might be very interesting for electronics or as electrode material.

Maybe* this is the wonder material with very low workfunction needed in the Photon Enhanced Thermionic Emitter future prototype :)

Swarm-based fabrication of interwoven composite tubes via a fully autonomous, cooperative system can help create architectural-scale structures in effective and efficient ways, including in remote environments.

first science results reported in Nature (as far as I know) from the Yutu-2 and Chang'e mission .... and they look very good!

Sure they are very useful! It will be even better if they manage to fit the data to modeled circulation of the lunar magma ocean that was formed posterior to the "Theia" body collision with Earth. The collision was the cause of the magma ocean in the first place. The question now is how this circulation pattern of the lava-moon "froze" in time upon phase transition to solid. Because, what crystallizes last in sequence, is more rich in "incompatible" with the crystal structure, elements, we might combine data+models to predict their location. Those incompatible tracers are mainly radioactively decaying elements that produce heat (google publications about lunar KREEP elements (potassium (K), rare earth elements(REE), and phosphorus(P)). By knowing where the KREEP is: - we know where to dig for them mining (if they are useful for something, eg. Phosphorus for plants to be grown on the Moon) - we avoid planning to build the future human colony on top of radioactives, of course. The hope is that the Moon, due to lack of plate tectonics, has preserved this "signature of the freezing sequence". Let's see.

thanks Nasia! very interesting comment

Cool technique to 3D print glass structures of small sizes.

Couldn't find more details on this but sounds interesting.

interesting indeed as a concept and to explore how far one can go to overcome some of the natural deficiencies of wood. regarding the main purpose of debris avoidance, it's typically not the structure that survives re-entry and one would have to see the environmental effect of what would be released in the atmosphere when burning.

Cool project from a few years ago! Checked for some recent updates but they seem to have adapted the concept to structural health monitoring and visual vibrometry to estimate material properties and wear.