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KentuckyFC writes "Binge drinking is a rapidly growing problem in city centers in the UK. "Vomiting, collapsing in the street, shouting and chanting loudly, intimidating passers-by and fighting are now regular night-time features of many British towns and cities," say economists who release the results of their study of the problem today (abstract). Their conclusion is that the pattern of binge drinking among individuals in the UK follows a small world network. In other words, you are much more likely to binge drink if your friends, family and work colleagues also indulge. Understanding the network properties could be crucial for stopping this kind of behaviour. In scale free networks, well-connected individuals such as film stars can have a disproportionate effect because they are linked to such a large number of others. So targeting these so-called hubs has been suggested as a good strategy for tackling behaviour of this kind. But today's study is significant because hubs don't exist in small world networks and that means that this approach won't work."
http://arxivblog.com/?p=484

KentuckyFC writes "X-ray crystallography has been a workhorse for chemists since the 1940s and 50s, revealing the 3D structure of complex biological molecules such as haemoglobin, DNA and insulin. But the technique has a severe limitation: it only works with molecules that form into crystals and that turns out to be a tiny fraction of the proteins that make up living things. But today, a team of US researchers say they have created the first image of a single uncrystallized virus using x-ray diffraction. The trick is to take a diffraction pattern of the virus and then subtract the diffraction pattern of its surroundings (abstract). The breakthrough paves the way for scientists to start teasing apart the 3D structures of the many proteins that have eluded biologists to date."

X-ray crystallography has been a workhorse for chemists since the 1940s and 50s, revealing the 3D structure of complex biological molecules such as haemoglobin, DNA and insulin. But the technique has a severe limitation: it only works with molecules that form into crystals and that turns out to be a tiny fraction of the proteins that make up living things. But today, a team of US researchers say they have created the first image of a single uncrystalised virus using x-ray diffraction. The trick is to take a diffraction pattern of the virus and then substract the diffraction pattern of its surroundings (abstract). The breakthrough paves the way for scientists to start teasing apart the 3D structures of the many proteins that have eluded biologists to date.
http://arxivblog.com/?p=480

KentuckyFC writes "Numerous studies have found the building blocks of life in meteorite samples. But critics point out that its hardly surprising that a rock that has slammed into the Earth at huge speed should end up covered in muck. If you're going to make the claim that these compunds came from space, you've got to prove it, they say. Today, an international group of astrobiologists provides the first unambiguous detection of extraterrestrial nucleobases, subunits from which nucleic acids such as DNA are formed. The proof consists of carbon isotope anaylsis of the compounds in a meteorite which landed in Australia in 1969. On Earth carbon-13 makes up about 1 per cent of carbon. The nucleobase samples from the meteorite, on the other hand, contain up to 44 per cent carbon-13 (abstract). That's as good a signature of extraterrestrial origin as you're likely to get."
http://arxivblog.com/?p=472

Quantum encryption is perfectly secure, at least in theory. In practice, however, it contains a number of loopholes. Now Japanese scientists have designed a quantum eavesdropper that exploits one of these loopholes to listen in to quantum conversations. Quantum encryption is secure because it is impossible to make a perfect copy of a quantum object. If it were possible, Eve could make a copy of a quantum message and pass on the original without anybody being the wiser. But copying destroys quantum objects, so the sender and receiver can always tell if they've been overheard. But the loophole is that an eavesdropper can make imperfect copies and use them to extract information from a quantum message without the sender or receiver knowing (abstract). The Japanese design does just this. That should send a shiver down the spine of any banks or government agencies that have begun to use some of the commercial quantum encryption systems now available.
http://arxivblog.com/?p=469

A team of German computer scientists has developed a program that reproduces all the known forms of spit (spam over internet telephony) attack . Their plan is to make the spitting software available to computer security experts wanting to test antispit strategies. Developing these won't be easy. There are various antispit techniques such as white lists that allow only calls from predetermined callers, Turing tests such as audio CAPTCHAs that make a caller prove he or she is human and payment-at-risk services where the caller makes a small payment in advance and is refunded immediately if the receiver acknowledges the call as legitimate. But all have weaknesses say the researchers. The main difference between junk calls and junk email is that the email arrives at your mail server before you access it. This gives the server time to analyse its content and filter out the junk before it gets to you. Not so with internet telephony which is why radically different strategies are needed.
http://arxivblog.com/?p=467

Einstein famously believed that the instantaeous effect of quantum entanglement would allow "spooky action-at-a-distance" in violation of special relativity. Every test of entanglement on Earth has so far agreed with quantum mechanics but naysayers continue to point out various loopholes that might allow the results of these experiments to be determined in advance rather than instantaneously as QM suggests. Today, an international team of scientists is proposing the mother of all entanglement experiments to be performed in space. The plan is to send entangled photons between an observer on the ground and one on the International Space Station . By the peculiarities of special relativity, the high relative velocity between the observers means that both will always be able to claim to have carried out their measurement first, thereby ruling out the naysayers' arguments (abstract). The experiment, called Space-QUEST, would be housed aboard Europe's Columbus module and would give the much-derided ISS a stab at doing some decent science for a change.
http://arxivblog.com/?p=460

KentuckyFC writes "You don't have to delve far into the realms of scriptwriting before you'll be pointed towards a book called Story by Robert McKee, which explains why scriptwriting is more akin to engineering than art. The book has become hugely influential and is now cited by thousands of scriptwriters as the inspiration for their films and TV series. Now researchers have used McKee's ideas to develop a computer model that analyses scripts in a repeatable, unambiguous and potentially-automatic way. The team have used the model to find unexpected similarities between the film Casablanca and the TV series CSI (Crime Scene Investigation). They now hope to use their model to develop project management software for scriptwriters, a package that might find a handy niche since many scripts, TV serials in particular, are now written by teams rather than individuals and so need careful management from the start."
http://arxivblog.com/?p=452

There are enough loopholes in the general theory of relativity to allow antimatter to fall up rather than down in a gravitational field. But we've never been able to make enough of the stuff to do the experiment. But at the European particle physics laboratory at CERN, where scientists have been refining the technique for making antihydrogen, researchers are designing an experiment called AEGIS that will finally settle the matter. The idea is simple: fire a beam of antihydrogen atoms and watch which way they fall but the details are fiendish (abstract). The answer should help solve a number of important conundrums such as why there is so little antimatter in our part of the universe and the value of the cosmological constant.
http://arxivblog.com/?p=450

A NASA-funded test of an entirely new way to control orbiting satellites has ended with the prototype arcing dangerously and parts of the machine exploding. The new propulsion system is based on the Lorentz force: that a charged particle moving through a magnetic field experiences a force perpendicular to both its velocity and the field. So the plan is to ensure that a satellite passing though the Earth's magnetic field is electrically charged so as to generate a force that can be used to steer the spacecraft. The advantage of the idea is that it requires no propellant which is a big deal since most satellites' lifespans are limited by the amount of fuel they can carry. But the first ground-based tests have't gone entirely to plan.
http://arxivblog.com/?p=432

Neutrinos are better than photons for communicating across the galaxy. That's the conclusion of a group of US astronomers who say that the galaxy is filled with photons that make communications channels noisy whereas neutrino comms would be relatively noise free. Photons are also easily scattered and the centre of the galaxy blocks them entirely. That means any civilisation advanced enough to have started to colonise the galaxy would have to rely on neutrino communications. And the astronomers reckon that the next generation of neutrino detectors should be sensitive enough to pick up ET's chatter (abstract).
http://arxivblog.com/?p=426

KentuckyFC writes "Astronomers have known for some time that the martian moon Phobos is gradually spiralling in towards the Red Planet at a about 20cm per year. At that rate, it'll hit Mars in about 11 million years. But one researcher is suggesting another fate (abstract). He calculates that long before Phobos hits, the planet's gravitational tidal forces could break it apart. And if that happens, Phobos will form a Saturn-like ring around Mars. The timescale? About 7.6 million years from now. That's a blink of an eye in astronomical terms"
http://arxivblog.com/?p=416

KentuckyFC writes "The world's oldest social network has been reconstructed from medieval land records in southwest France. A team of scientists and historians used this dataset, which record the date, the type of transaction and the people involved, to work out the network of links between medieval peasants in the area between 1260 and 1340 AD . These kinds of networks could provide anthropolgists with an exciting new way to study historical societies by asking how this medieval network differs from the kind of networks we see in the 21st century. The team promise an analysis soon (abstract). All that's left is to christen the new science of the study ancient social networks. Any suggestions?"
http://arxivblog.com/?p=413

Water is the most abundant solid material in space. But although astronomers see it on planets, moons, in comets and in interstellar clouds, nobody has been able to show how it forms. In theory, it should form easily when oxygen and atomic hydrogen meet. The problem is that there is not enough of it floating around as gas in interstellar dust clouds. So instead, the thinking is that water must form when atomic hydrogen interacts with frozen solid oxygen on the surface of dust grains in these clouds. Now Japanese astronomers have demonstrated this process for the first time in the lab in conditions that simulate interstellar space. That's cool because all the water in the solar system, including almost every drop you drink on Earth today, must have formed in exactly this way more than 5 billion years ago in a pre-solar dustcloud (abstract).
http://arxivblog.com/?p=397

One of the biggest problems in nuclear proliferation is verifying that countries are not secretly transferring fissile material by taking it out of reactors and selling it. Now a group of US scientists say they've developed a machine that can remotely detect whether a reactor has been switched on and off by detecting the antineutrinos produced by nuclear reactions. The detector is about the size of a car engine and is designed to be left near a reactor to record data. The group has been testing a prototype at the San Onofre Nuclear Generating Station in Southern California and says it works well (abstract). Now its up to the International Atomic Energy Authority in Vienna to decide whether to deploy the new machine
http://arxivblog.com/?p=393