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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.

From the machinery of life to the fate of the cosmos, what can't science explain?

Those who are easily distracted from the task in hand may have "too much brain".

A new strain of MRSA has been identified in cows' milk and in people, but don't stop drinking milk - the bug is killed off in pasteurisation. However, the strain evades detection by standard tests used by some hospitals to screen for MRSA (methicillin-resistant Staphylococcus aureus), potentially putting people at risk. Laura Garcia Alvarez, then at the University of Cambridge, and colleagues were studying infections in British cows when they discovered antibiotic-resistant bacteria that they thought were MRSA. However, tests failed to identify the samples as any known strains of the superbug. Sequencing the mystery bacteria's genomes revealed a previously unknown strain of MRSA with a different version of a gene called MecA. The new strain was also identified in samples of human MRSA, and is now known to account for about 1 per cent of human MRSA cases.

The lushest patches of some jungles are rooted in enigmatic black soil - with unexpected origins

Researchers at the University of Rochester have determined that when humans see the color red, their reactions become both faster and more forceful. The researchers measured the reactions of students in two experiments. In the first, 30 fourth-through-10th graders pinched and held open a metal clasp. Right before doing so, they read aloud their participant number written in either red or gray crayon. In the second experiment, 46 undergraduates squeezed a handgrip with their dominant hand as hard as possible when they read the word "squeeze" on a computer monitor. The word appeared on a red, blue, or gray background. In both scenarios, red significantly increased the force exerted, with participants in the red condition squeezing with greater maximum force than those in the gray or blue conditions, the researchers said. Ref.: Andrew J. Elliot, Henk Aarts, Perception of the color red enhances the force and velocity of motor output, Emotion, Vol 11(2), Apr 2011, 445-449

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.

Theodore Berger and his team at the USC Viterbi School of Engineering's Department of Biomedical Engineering have developed a neural prosthesis for rats that is able to restore their ability to form long-term memories after they had been pharmacologically blocked. In a dramatic demonstration, Berger blocked the ability to rats to form long-term memories by using pharmacological agents to disrupt the neural circuitry that communicates between two subregions of the hippocampus, CA1 and CA3, which interact to create long-term memory, prior research has shown. The rats were unable to remember which lever to pull to gain a reward, or could only remember for 5-10 seconds, when previously they could remember for a long period of time. The researchers then developed an artificial hippocampal system that could duplicate the pattern of interaction between CA3-CA1 interactions. Long-term memory capability returned to the pharmacologically blocked rats when the team activated the electronic device programmed to duplicate the memory-encoding function. The researchers went on to show that if a prosthetic device and its associated electrodes were implanted in animals with a normal, functioning hippocampus, the device could actually strengthen the memory being generated internally in the brain and enhance the memory capability of normal rats. "These integrated experimental modeling studies show for the first time that with sufficient information about the neural coding of memories, a neural prosthesis capable of real-time identification and manipulation of the encoding process can restore and even enhance cognitive mnemonic processes," says the paper. Next steps, according to Berger and Deadwyler, will be attempts to duplicate the rat results in primates (monkeys), with the aim of eventually creating prostheses that might help human victims of Alzheimer's disease, stroke, or injury recover function. Ref.: "A Cortical Neural Prosthesis for Restoring and Enhancing

Life must have begun with a simple molecule that could reproduce itself - and now we think we know how to make one

Apply the electrodes... Externally modulating the brain's activity can boost its performance. The easiest way to manipulate the brain is through transcranial direct current stimulation (tDCS), which involves applying electrodes directly to the head to influence neuron activity with an electric current. Roi Cohen Kadosh's team at the University of Oxford showed last year that targeting tDCS at the brain's right parietal lobe can boost a person's arithmetic ability - the effects were still apparent six months after the tDCS session (newscientist.com/article/dn19679). More recently, Richard Chi and Allan Snyder at the University of Sydney, Australia, demonstrated that tDCS can improve a person's insight. The pair applied tDCS to volunteers' anterior frontal lobes - regions known to play a role in how we perceive the world - and found the participants were three times as likely as normal to complete a problem-solving task (newscientist.com/article/dn20080). Brain stimulation can also boost a person's learning abilities, according to Agnes Flöel's team at the University of Münster in Germany. Twenty minutes of tDCS to a part of the brain called the left perisylvian area was enough to speed up and improve language learning in a group of 19 volunteers (Journal of Cognitive Neuroscience, DOI: 10.1162/jocn.2008.20098). Using the same technique to stimulate the brain's motor cortex, meanwhile, can enhance a person's ability to learn a movement-based skill (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0805413106).

Last year 10 children died in California in the worst whooping cough outbreak to sweep the state since 1947. In the first six months of 2011, the Centers for Disease Control and Prevention recorded 10 measles outbreaks-the largest of which (21 cases) occurred in a Minnesota county, where many children were unvaccinated because of parental concerns about the safety of the standard MMR vaccine against measles, mumps and rubella. At least seven infants in the county who were too young to receive the MMR vaccine were infected.

Full Videos of the Singularity Summit 2010 Talks

Traditional methods of transmitting data, such as fibre optics or laser-based radar, require roughly 100 photons to transmit a single bit of data. Now a team led by Saikat Guha at Raytheon BBN Technologies in Cambridge, Massachusetts, say they can transmit 10 bits on a single photon - a 1000-fold improvement.

In 1967, Simon Kochen and Ernst Specker proved mathematically that even for a single quantum object, where entanglement is not possible, the values that you obtain when you measure its properties depend on the context. So the value of property A, say, depends on whether you chose to measure it with property B, or with property C. In other words, there is no reality independent of the choice of measurement. It wasn't until 2008, however, that Alexander Klyachko of Bilkent University in Ankara, Turkey, and colleagues devised a feasible test for this prediction. They calculated that if you repeatedly measured five different pairs of properties of a quantum particle that was in a superposition of three states, the results would differ for the quantum system compared with a classical system with hidden variables. That's because quantum properties are not fixed, but vary depending on the choice of measurements, which skews the statistics. "This was a very clever idea," says Anton Zeilinger of the Institute for Quantum Optics, Quantum Nanophysics and Quantum Information in Vienna, Austria. "The question was how to realise this in an experiment." Now he, Radek Lapkiewicz and colleagues have realised the idea experimentally. They used photons, each in a superposition in which they simultaneously took three paths. Then they repeated a sequence of five pairs of measurements on various properties of the photons, such as their polarisations, tens of thousands of times. A beautiful experiment They found that the resulting statistics could only be explained if the combination of properties that was tested was affecting the value of the property being measured. "There is no sense in assuming that what we do not measure about a system has [an independent] reality," Zeilinger concludes.

Fats in foods like potato chips and french fries make them nearly irresistible because they trigger natural marijuana-like chemicals in the body called endocannabinoids, researchers at the University of California, Irvine, have found. The researchers discovered that when rats tasted something fatty, cells in their upper gut started producing endocannabinoids, while sugars and proteins did not have this effect. How fats create, like, a buzz It starts on the tongue, where fats in food generate a signal that travels first to your brain, and then through a nerve bundle called the vagus to your intestines. There, the signal stimulates the production of endocannabinoids, which initiates a surge in cell signaling that prompts you to totally pig out - probably by initiating the release of digestive chemicals linked to hunger and satiety that compel us to eat more. And that leads to obesity, diabetes and cancer, the researchers said. But they suggest it might be possible to curb this process by obstructing endocannabinoid activity: for example, by using drugs that "clog" cannabinoid receptors. The trick: bypassing the brain to avoid creating anxiety and depression (which happens when endocannabinoid signaling is blocked in the brain). I'm guessing McDonald's won't be adding that drug to their fries. Ref.: Daniele Piomelli, et al., An endocannabinoid signal in the gut controls dietary fat intake, PNAS, 2011; in press

An immune-suppressing drug called rapamycin could possibly treat Hutchinson-Gilford progeria syndrome (HGPS), a rare genetic disease that causes premature aging, and advance biological understanding of the normal aging process, according to researchers from the National Human Genome Research Institute (NHGRI) at the National Institutes of Health, the University of Maryland and Massachusetts General Hospital. Progeria is a genetic disorder characterized by dramatic premature aging. "Progerin that causes progeria also accumulates, although in very small amounts, in normal aging," said Dimitri Krainc, M.D., Ph.D., associate professor of neurology at Harvard Medical School. "However, if rapamycin proves to have beneficial effects in lifespan in humans it is safe to assume that it will not be just because it may clear progerin from cells, but also because it clears other toxic products that accumulate during aging." Ref.: Francis S. Collins, et al., Rapamycin Reverses Cellular Phenotypes and Enhances Mutant Protein Clearance in Hutchinson-Gilford Progeria Syndrome Cells, Science, 2011; [DOI: 10.1126/scitranslmed.3002346]

Listen up, Facebook and Twitter groupies: how easily can social pressure affect your memory? Very easily, researchers at the Weizmann Institute and University College London have proved, and they think they even know what part of the brain is responsible. The participants conformed to the group on these "planted" responses, giving incorrect answers nearly 70% of the time. Volunteers watched a documentary film in small groups. Three days later, they returned to the lab individually to take a memory test, answering questions about the film. They were also asked how confident they were in their answers. They were later invited back to the lab to retake the test. This time, the subjects were also given supposed answers of the others in their film-viewing group (along with social-media-style photos) while being scanned in a functional MRI (fMRI) that revealed their brain activity. Is most of what you know false? Planted among these were false answers to questions the volunteers had previously answered correctly and confidently. The participants conformed to the group on these "planted" responses, giving incorrect answers nearly 70% of the time. To determine if their memory of the film had actually undergone a change, the researchers invited the subjects back to the lab later to take the memory test once again, telling them that the answers they had previously been fed were not those of their fellow film watchers, but random computer generations. Some of the responses reverted back to the original, correct ones, but get this: despite finding out the scientists messed with their minds, close to half of their responses remained erroneous, implying that the subjects were relying on false memories implanted in the earlier session. An analysis of the fMRI data showed a strong co-activation and connectivity between two brain areas: the hippocampus and the amygdala. Social reinforcement could act on the amygdala to persuade our brains to replace a strong memory wi

Scientists at the McEwen Centre for Regenerative Medicine and the Ontario Cancer Institute have isolated a human blood stem cell in its purest form: as a single stem cell capable of regenerating the entire blood system. "This discovery means we now have an increasingly detailed road map of the human blood development system, including the much sought after stem cell," says principal investigator John Dick, who holds a Canada Research Chair in Stem Cell Biology and is a Senior Scientist at the McEwen Centre for Regenerative Medicine and the Ontario Cancer Institute, University Health Network (UHN). "We have isolated a single cell that makes all arms of the blood system, which is key to maximizing the potential power of stem cells for use in more clinical applications. Stem cells are so rare that this is a little like finding a needle in a haystack," says Dr. Dick. Ref.: John E. Dick, Isolation of Single Human Hematopoietic Stem Cells Capable of Long-Term Multilineage Engraftment, Science, July 2011: Vol. 333 no. 6039 pp. 218-221 [DOI: 10.1126/science.1201219]