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Organic compounds of unexpected complexity exist throughout the universe, Prof. Sun Kwok and Dr. Yong Zhang of the University of Hong Kong have discovered, suggesting that complex organic compounds can be synthesized in space even when no life forms are present. The organic substance they found contains a mixture of aromatic (ring-like) and aliphatic (chain-like) components that are so complex, their chemical structures resemble those of coal and petroleum. Since coal and oil are remnants of ancient life, this type of organic matter was thought to arise only from living organisms. Unidentified radiation from the universe The researchers investigated an unsolved phenomenon: a set of infrared emissions detected in stars, interstellar space, and galaxies, known as "Unidentified Infrared Emission features." From observations taken by the Infrared Space Observatory and the Spitzer Space Telescope, Kwok and Zhang showed that the astronomical spectra have chemical structures that are much more complex that previously thought. By analyzing spectra of star dust formed in exploding stars called novae, they show that stars are making these complex organic compounds on extremely short time scales of weeks, and ejecting it into the general interstellar space, the region between stars. "Our work has shown that stars have no problem making complex organic compounds under near-vacuum conditions," says Kwok. "Theoretically, this is impossible, but observationally we can see it happening." Most interestingly, this organic star dust is similar in structure to complex organic compounds found in meteorites. Since meteorites are remnants of the early Solar System, the findings raise the possibility that stars enriched the early Solar System with organic compounds. The early Earth was subjected to severe bombardments by comets and asteroids, which potentially could have carried organic star dust. Whether these delivered organic compounds played any role in the development of l

The scientists suggest that life on Earth originated at photosynthetically-active porous structures, similar to deep-sea hydrothermal vents, made of zinc sulfide (more commonly known as phosphor). They argue that under the high pressure of a carbon-dioxide-dominated atmosphere, zinc sulfide structures could form on the surface of the first continents, where they had access to sunlight.

"A new bioprinter developed at a hackerspace can print living cells for less than the cost of an iPod touch. 3-D bioprinters have the potential to change the way medical research is conducted, even print living tissue and replacement organs, but they are expensive and highly specialized. They literally build living structures, like blood vessels or skin tissue, cell by cell, revolutionizing biomedical engineering. Unfortunately, they're expensive, rare, and require a Ph.D. (or two) to operate successfully. Frustrated by their cost and exclusivity, a group of makers at the DIYbio hackerspace BioCurious are developing a system open to anyone with a soldering iron and a serious passion for cell biology."

"Arches is an open-source, web-based, geospatial information system for cultural heritage inventory and management. Purpose-built for the international cultural heritage field, Arches is designed to record all types of immovable heritage, including archaeological sites, buildings and other historic structures, landscapes, and heritage ensembles or districts."

Droplet network printer ""We aren't trying to make materials that faithfully resemble tissues, but rather structures that can carry out the functions of tissues," said Professor Hagan Bayley of Oxford University's Department of Chemistry, who led the research. "We've shown that it is possible to create networks of tens of thousands of connected droplets. The droplets can be printed with protein pores to form pathways through the network that mimic nerves and are able to transmit electrical signals from one side of a network to the other.""

The goal of this project is the development of cognitive non-computational structure close to those of human brain. In fact - this is an attempt to create an artificial brain.

UBY is a large-scale lexical-semantic resource for natural language processing (NLP) based on the ISO standard Lexical Markup Framework (LMF). UBY combines a wide range of information from expert-constructed and collaboratively constructed resources for English and German. Currently, UBY holds structurally and semantically interoperable versions of nine resources in two languages:  English WordNet, Wiktionary, Wikipedia, FrameNet and VerbNet,  German Wikipedia, Wiktionary and GermaNet, and multilingual OmegaWiki. 

"We found that adult Nod2-deficient mice display a substantially altered microbial community structure and a significantly elevated bacterial load in their faeces and terminal ileum compared to their wild-type counterparts. Interestingly, we demonstrate that these findings are also present in weaning mice, indicating a profound influence of Nod2 on the early development and composition of the intestinal microbiota. We demonstrate that NOD2 genotypes also influence the microbial composition in humans. Conclusions Our results point to an essential role of Nod2 for the temporal development and composition of the host microbiota, both in mice and in humans, which may contribute to the complex role of NOD2 for the aetiopathogenesis of Crohn's disease. "

"The SOS-Ras-Raf-MAPK cascade plays a central role here. In about 25% of human tumors, Ras proteins are present in structurally altered forms that enable them to release a flux of mitogenic signals into cells, without ongoing stimulation by their normal upstream regulators (Medema and Bos 1993). We suspect that growth signaling pathways suffer deregulation in all"

Our genetic code is translated by two super-families of modern-day enzymes. Carter's research team created and superimposed digital three-dimensional versions of the two super-families to see how their structures aligned. Carter found that all the enzymes have virtually identical cores that can be extracted to produce "molecular fossils" he calls Urzymes-Ur meaning earliest or original. The other parts, he said, are variations that were introduced later, as evolution unfolded. These two Urzymes are as close as scientists have gotten to the actual ancient enzymes that would have populated the Earth billions of years ago.

Living Science is an open and editable database for publication metadata, structured as author profiles and for all research fields. There are currently 100345 author profiles.

To see if quantum processes play a role in determining the shape of DNA, Elisabeth Rieper of the National University of Singapore and colleagues modelled each base pair as a cloud of electrons that oscillates around a positively charged nucleus. The team found that quantum entanglement between these clouds helped DNA to maintain its helical structure.

"Basically, any computing device (or switch, or router) that is based on light requires a nonlinear interaction between different light beams, but light doesn't like to do nonlinear stuff. With current technology, you can get efficient nonlinear optical interactions, but the hardware is kind of bulky or very delicate. Not the sort of thing you want to put in a billion devices. What my friends in Barcelona have demonstrated is that it's possible to create a relatively efficient optical nonlinear interaction in a nano-structured metallic surface. "

The fruit fly has evolved a method for arranging the tiny, hair-like structures it uses to feel and hear the world that's so efficient a team of scientists in Israel and at Carnegie Mellon University says it could be used to more effectively deploy wireless sensor networks and other distributed computing applications.

COULD the structure of space and time be sketched out inside a cousin of plain old pencil lead? The atomic grid of graphene may mimic a lattice underlying reality, two physicists have claimed, an idea that could explain the curious spin of the electron. Graphene is an atom-thick layer of carbon in a hexagonal formation. Depending on its position in this grid, an electron can adopt either of two quantum states - a property called pseudospin which is mathematically akin to the intrinsic spin of an electron. Most physicists do not think it is true spin, but Chris Regan at the University of California, Los Angeles, disagrees. He cites work with carbon nanotubes (rolled up sheets of graphene) in the late 1990s, in which electrons were found to be reluctant to bounce back off these obstacles. Regan and his colleague Matthew Mecklenburg say this can be explained if a tricky change in spin is required to reverse direction. Their quantum model of graphene backs that up. The spin arises from the way electrons hop between atoms in graphene's lattice, says Regan. So how about the electron's intrinsic spin? It cannot be a rotation in the ordinary sense, as electrons are point particles with no radius and no innards. Instead, like pseudospin, it might come from a lattice pattern in space-time itself, says Regan. This echoes some attempts to unify quantum mechanics with gravity in which space-time is built out of tiny pieces or fundamental networks (Physical Review Letters, vol 106, p 116803). Sergei Sharapov of the National Academy of Sciences of Ukraine in Kiev says that the work provides an interesting angle on how electrons and other particles acquire spin, but he is doubtful how far the analogy can be pushed. Regan admits that moving from the flatland world of graphene to higher-dimensional space is tricky. "It will be interesting to see if there are other lattices that give emergent spin," he says.

It's not quite Cyclops, the sci-fi superhero from the X-Men franchise whose eyes produce destructive blasts of light, but for the first time a laser has been created using a biological cell. The human kidney cell that was used to make the laser survived the experience. In future such "living lasers" might be created inside live animals, which could potentially allow internal tissues to be imaged in unprecedented detail. It's not the first unconventional laser. Other attempts include lasers made of Jell-O and powered by nuclear reactors (see box below). But how do you go about giving a living cell this bizarre ability? Typically, a laser consists of two mirrors on either side of a gain medium - a material whose structural properties allow it to amplify light. A source of energy such as a flash tube or electrical discharge excites the atoms in the gain medium, releasing photons. Normally, these would shoot out in random directions, as in the broad beam of a flashlight, but a laser uses mirrors on either end of the gain medium to create a directed beam. As photons bounce back and forth between the mirrors, repeatedly passing through the gain medium, they stimulate other atoms to release photons of exactly the same wavelength, phase and direction. Eventually, a concentrated single-frequency beam of light erupts through one of the mirrors as laser light.

The Bolshoi simulation is the most accurate cosmological simulation of the evolution of the large-scale structure of the universe yet made ("bolshoi" is the Russian word for "great" or "grand").  The first two of a series of research papers describing Bolshoi and its implications have been accepted for publication in the Astrophysical Journal. The first data release of Bolshoi outputs, including output from Bolshoi and also the BigBolshoi or MultiDark simulation of a volume 64 times bigger than Bolshoi, has just been made publicly available to the world's astronomers and astrophysicists.

Together with ever-improving observations of the early universe, grand simulations are beginning to paint a single, unifying picture of why the universe looks as it does. At its heart is an almost invisible scaffold of dark matter and cold gas on which the visible constituents of the universe hang - a structure known as the cosmic web.

James Crutchfield, Physics Professor at the University of California at Davis, and graduate students Christopher Ellison and John Mahoney, have developed the analogy of scientists as cryptologists who are trying to glean hidden information from Nature. As they explain, "Nature speaks for herself only through the data she willingly gives up." To build good models, scientists must use the correct "codebook" in order to decrypt the information hidden in observations and so decode the structure embedded in Nature's processes.