New super-dense forms of carbon outshine diamond

We can all only dream of owning rocks made of these. Simulations have revealed three stable forms of pure carbon that would sparkle more than diamond if synthesised.

Carbon atoms can be combined in different configurations with widely varying properties. Graphite and diamond are the most familiar, while more exotic allotropes include graphene, with versatile electrical properties, and M-carbon and Bct-carbon, which rival diamond's legendary hardness.

To explore whether forms of carbon denser than diamond might be possible, Artem Oganov of Stony Brook University in New York and colleagues systematically simulated different configurations of carbon atoms at different temperatures and pressures. Three – named hP3, tI12 and tP12 – seemed stable enough to be made in principle.

The simulations show none would be as hard as diamond, but all three would be between 1.1 and 3.2 per cent denser. "These new allotropes are significantly denser than any of the known allotropes of carbon," says Oganov.

This gives them a higher refractive index – a measure of the extent to which they bend light – leading to greater lustre and sparkle.
Superconducting carbon?

The simulations also suggest that the three materials have band gaps – the amount of energy needed for electrons to jump from one energy level to another – that are very different to one another. One of them, tP12, has the largest band gap of any carbon allotrope. This variability may make the allotropes good candidates for superconductors – exotic substances that conduct electricity without resistance, says Oganov.

According to Boris Yakobson at Rice University in Houston, Texas, a large variation in band gap implies strong interactions between electrons and packets of energy in the lattice called phonons. This in turn could lead to the formation of electron couplings called Cooper pairs, which are necessary for superconductivity.

The presence of widely varying band gaps might also give the materials other unique properties. "The large spread of band gaps gives an excellent playground for engineering new electronic materials," adds Oganov.
Hard to make

Creating the three new materials could be difficult, though. "It is not clear how we can fabricate them," says Vadim Brazhkin of the Institute for High Pressure Physics in Troitsk, Russia, who was not involved in the research.

"Using standard pristine materials, such as graphite or amorphous carbon [an allotrope in which the atoms have no crystal structure], we can possibly obtain a tiny amount of new materials using extreme pressure treatment," he says.

Read more at New Scientist

Cloned Cows to Produce Human-Like Milk

An Argentine laboratory announced that it had created the world's first transgenic cow, using human genes that will allow the animal to produce the equivalent of mothers' milk.

"The cloned cow, named Rosita ISA, is the first bovine born in the world that incorporates human genes that contain the proteins present in human milk," Argentina's National Institute of Agrobusiness Technology said in a statement on Thursday.

Rosita ISA was born on April 6 by Ceasarian because she weighed more than 45 kilos (99 pounds), about twice the normal weight of Jersey cows, according to the statement.
biotechnology

As an adult, "the cow will produce milk that is similar to humans," the statement said.

"Our goal was to raise the nutritional value of cows' milk by adding two human genes, the protein lactoferrin, which provides infants with anti-bacterial and anti-viral protection, and lysozyme, which is also an anti-bacterial agent," said researcher Adrian Mutto at a press conference.

Read more at Discovery News

Extra Gene Copies May Trigger Some Cases of Autism

Viewed from some perspectives, autism is a genetic disease. Studies of identical twins show that, when one sibling is affected, the other is also, with a frequency approaching 90 percent. Several genes associated with autism have been identified due to their prevalence in individual families with high rates of autism. All of that, however, doesn’t help explain why there are so many of what appear to be sporadic cases of autism, where a single individual in a family has the disorder; these account for the majority of all cases of autism.

Over the past several years, a case has been building that many of the sporadic cases are also genetic, the result of brand-new mutations that appear only in the affected individual. A set of studies that appear in the journal Neuron make a compelling case that these new mutations can also account for a significant fraction of the total incidence of autism, but still aren’t common enough to fully account for the incidence of the disease.

The new studies rely heavily on a project developed by a private foundation, the Simons Simplex Collection. The Simons Foundation has worked with academic researchers to obtain DNA and cell samples from thousands of unaffected parents and their autistic children; unaffected siblings are also included. This has allowed researchers to screen for changes in the DNA that are unique to the affected individual. In this case, the papers looked for what are called copy number variations, or CNVs, which occur when a chromosome has either ended up with an extra copy of part of the genome, or seen a part of the genome deleted. CNVs will often contain genes, so they create differences in the dose of these genes.

The studies found slightly different numbers, but the same general trend: New CNVs (deletions or duplications that are not present in either parent) are much more common in autistic children than they are in their unaffected siblings. One study found that they showed up 3.4 times more often; the other showed 3.9 times. In either case, there were many more changes in the dose of genes among autistic individuals. Moreover, most of these changes are rare, showing up in only one or a few individuals. This low frequency implies that, with a larger population, even rarer CNVs would be uncovered. The statistics are such that the authors estimate that there may be several hundred potential sites in the genome that could be linked to autism.

A number of areas that were previously associated with autism came out of the screens, but many of the sites were brand-new. In one case, the authors found duplications of a region produced autism; previously, others had found that deletion of this region produced a disorder where affected individuals are unusually gregarious.

An accompanying paper looks at what the genes present in these CNVs do. In general, they seem to be involved in what you’d expect: synapse formation, the internal structure of nerve cells, and the generation of the axons and dendrites that help nerve cells form connections with one another. Thus, the findings help support the general picture that autism is associated with problems with wiring the brain up, rather than the production or function of nerve cells.

Where do these new results leave us in terms of the root causes of autism? They certainly support the general idea that even sporadic cases of autism are caused by new mutations. But on their own, CNVs don’t seem to be occurring at a rate that is sufficient to account for all the sporadic cases of autism. There is the chance that many of the same genes we see within the CNVs, however, are damaged by smaller mutations, including single base changes, that can’t be detected by the techniques used in these studies. Identifying these sorts of mutations, however, will probably require whole-genome sequencing of thousands of individuals, so we’re unlikely to see it in the near future.

Read more at Wired Science

Council quizzed over zombie invasion plans by resident

A "concerned citizen", Robert Ainsley, lodged his query on Tuesday, asking: "Can you please let us know what provisions you have in place in the event of a zombie invasion?"

He added: "Having watched several films it is clear that preparation for such an event is poor and one that councils throughout the kingdom must prepare for."

The authority has yet to formally respond but has indicated that there are no specific references to zombies in its emergency plans.

Leicester City Council has 20 working days to answer but its head of information governance, Lynn Wyeth, took to local radio yesterday to address the issue.

She said: "We've had a few wacky ones but this one did make us laugh.

"It's one of those questions that you could do a one-liner saying there is nothing specifically in the emergency plan to state a response to a zombie invasion.

"But you could look at it in more depth and say, 'Which parts of the emergency plan could you apply to a zombie invasion?' - as it would have the same impact as perhaps some other disaster or attack."

She told the BBC: "If it's specifically about zombies then I would say, from my recollection of the plan... then unfortunately there's nothing in there... saying how we would respond to zombies."

Ms Wyeth said that the council was required by law to responond to all requests made under the Freedom of Information Act.

Read more at The Telegraph

Dogs can instinctively sense a friendly face

Dog owners often claim their pets have an uncanny ability to understand them, sensing tiredness, depression and illness even if they hide the signs.

Now scientists claimed to have proved the phenomenon and that the ability is natural and not just learnt.

Dr Monique Udell and her team from Florida University carried out two experiments involving both domesticated dogs and their relative the wolf.

The two sets of animals were given the opportunity to beg for food, either from an attentive person or from a person who ignored the potential beggar.

The researchers showed for the first time that wolves, like domestic dogs, are capable of begging successfully for food by approaching the attentive human.

This demonstrates that both species – domesticated and non-domesticated – have the capacity to behave in accordance with a human's attentional state.

They are therefore likely born with the ability, since wolves would not have had much practice, which the typical pet dog gains by begging for treats during dinner and at other times.

Dogs did, however, get better at the ability the more time they spent with humans.

Dogs in shelters were not nearly as good as well loved pets, demonstrating that exposure to humans allows dogs to hone their natural people-reading skills more.

Read more at The Telegraph

Jack Horner the man who’s making a “Chickenosaurus”

Renowned paleontologist Jack Horner has spent his career trying to reconstruct a dinosaur. He’s found fossils with extraordinarily well-preserved blood vessels and soft tissues, but never intact DNA. So, in a new approach, he’s taking living descendants of the dinosaur (chickens) and genetically engineering them to reactivate ancestral traits — including teeth, tails, and even hands — to make a “Chickenosaurus”.

Police hunt ‘psychic’ after false tip-off about mass grave of children

Police in Texas are investigating a woman who claimed to be a psychic after she sparked an ultimately fruitless hunt for a mass grave of dismembered bodies.

Local officers and FBI agents raided a rural farmhouse in Hardin, north-east of Houston, after receiving the report that it held up to 30 bodies, including children.

After finding nothing, police gave up the search – but not before ”a source” had told CBS news that “a lot” of dismembered children’s bodies had indeed been found at the scene, sparking a global news story.

Liberty county judge Craig McNair, the county’s top elected official, said the sheriff’s office had received two calls from the person. The first came on Monday, directing officers to an address in Hardin, but after officers found nothing the same caller told police on Tuesday that they had the wrong house.

Officers approached the scene of the second tip-off on Tuesday morning and said there was blood on a back door and a foul odour coming from the house, leading to the search warrant.

“We have to take tips like this very seriously,” McNair said.

However the Houston Chronicle has since reported that the calls had come from a woman who claimed to have psychic powers, prompting questions over why police responded so vigorously.

The FBI were summoned and officers scrambled to the home on Tuesday, but not before a source apparently told CBS the bodies had already been found. Local television station KPRC was given the same information and the story was promptly followed up by news agenciesAFP and Reuters.

Before long the news that 30 bodies had been uncovered in a mass grave was leading BBC and Sky News channels in the UK and across the world. The Guardian contributed its own version.

Liberty county sheriff’s captain Rex Evans said authorities took the tip seriously in part because the caller had details about the inside of the house that only someone who had seen it could have known.

He said authorities were working to track her down. They had a name and number.

Asked if he thought the tip was a hoax, Evans said only that police found no bodies or anything to indicate a murder. “We are going to continue our investigation and find out how this individual had this information in the first place,” Evans said, adding that the caller may face criminal proceedings.

Full story at The Guardian

Risk, Probability and How Brains Are Easily Misled

The World Science Festival’s panel on Probability and Risk started out in an unusual manner: MIT’s Josh Tennenbaum strode onto a stage and flipped a coin five times, claiming he was psychically broadcasting each result to the audience. The audience dutifully wrote down the results they thought he had seen on note cards, and handed them in when the experiment was over. Towards the end of the program, he announced there were low odds that even one person in the audience had guessed the right order of results. When he announced them, however, about a dozen people raised their hands, saying that was what they had written down.

Is Tennenbaum psychic? The audience sprinkled with liars?

Neither, according to Tennenbaum. Instead, we’re the victims of our own tendency to expect that a series of coin tosses will produce results that look satisfyingly random to us. As a result, we’re unlikely to suggest a series of four heads followed by a tails. In the same way, we’re likely to end up choosing something like TTHTH. So likely, in fact, that if the coin flips do happen to produce one of these random looking patterns, it’ll be overrepresented in whatever crowd we’re testing. Instant psychic ability, with built in statistical significance.


The funny thing is that this isn’t the product of some mental weakness—Tennenbaum suggested that it’s the product of an excellent built-in sense of what makes for a random pattern. If you graph the frequency of various possible results, it’s possible to see a pattern of peaks at random-looking series and valleys at the ones that chance would seem to disfavor. Comparing the graph generated from our audience to one produced in the 1930s, and it was obvious that the pattern was nearly identical—what we think of as random appears to be quite stable.

The one exception, he noted, was when he performed the experiment with a math-savvy audience. There, a part of the audience recognizes that any series is equally probable, so they are more likely to put down all heads or all tails.

Subverting wisdom

Although Tennenbaum clearly felt that our intuitive feel for randomness was a positive feature, other speakers on the panel noted that human decision-making could obviously get stuck or be manipulated. Mathematician Amir Aczel mentioned that many trained mathematicians can’t wrap their heads around the Monty Hall problem, in which changing probabilities dictate how you should act on a popular game show. It’s relatively easy to run through the probabilities that show which action you should take, but the answer remains counterintuitive—even for those with an exceptional grasp of math.

And that’s assuming, as co-panelist Gerd Gigerenzer noted, that Monty isn’t being malicious. A crowd experiment run by physicist Leonard Mlodinow showed how easy it is to manipulate a people’s answers to simple questions without doing anything overt. Mlodinow divided the audience in half, and asked both halves separately to estimate the number of countries in Africa. This is a standard “wisdom of the crowds” sort of question, where the mean should be somewhere close to the actual number. Instead, the two groups had wildly divergent means, with one half of the audience answering well above the actual answer, the second significantly below.

How’d he manage this? Prior to asking the actual number, Mlodinow had asked a question that subtly primed each group. For one half of the audience, he asked if they thought there were more than 180 countries in Africa; this group ended up with a much higher mean. The second half was asked if there were more than five. Their answers were, on average, too low. Although this was a case of conscious manipulation, it’s easy to see how a similar effect could be generated accidentally, simply based on (for example) the order of questions in a survey.

How do we fix this?

Does all this mean that humans will perpetually remain stuck when it comes to risk and probability? Possibly not, but we have to be careful. That was the message of Gerd Gigerenzer, who helps train decision makers in how to evaluate probabilities. Gigerenzer consistently noted that language was important when it comes to dealing with probabilities.

The most compelling example he gave was one he used when working in medical education. He described the probabilities associated with a breast cancer test: one percent of women tested have the disease, and the test is 90 percent accurate, with a nine percent false positive rate. With all that information, what do you tell a woman who tests positive about the likelihood they have the disease? For a lot of people in medicine, the question leaves them stumped; a typical survey of doctors (and the World Science Festival audience) reveals that there’s no single consensus about the probability that the test indicates a real case of cancer.

Read more at Wired Science

Top bizarre health remedies

Below is a list of the top bizarre health remedies that have been suggested over the years.

 - A peacock feather tied to the leg cures lethal snake venom.

- Cow urine can cure liver complaints, cancers, heart ailments, AIDS and constipation. It is currently being developed into a healthy soft drink

- Cow dung keep homes antiseptic and cool when used as flooring cement.

- Crushed human skull powder can treat epilepsy

- Indian otter testicles is a cure for ‘sexual weakness'

- Green apples cure claustrophobia

- Beer bath to help slow down aging

- Bats blood for help eye infections

- Spider's webs as a cure for malaria

Taken from The Telegraph

Remembering Alan Turing

Alan Mathison Turing, OBE, FRS (23 June 1912 – 7 June 1954), was an English mathematician, logician, cryptanalyst and computer scientist. He was highly influential in the development of computer science, providing a formalization of the concepts of “algorithm” and “computation” with the Turing machine, which played a significant role in the creation of the modern computer. Turing is widely considered to be the father of computer science and artificial intelligence.

During the Second World War, Turing worked for the Government Code and Cypher School at Bletchley Park, Britain’s codebreaking centre. He devised a number of techniques for breaking Germanciphers, including the method of the bombe, an electromechanical machine that could find settings for the Enigma machine.

Turing’s homosexuality resulted in a criminal prosecution in 1952, when homosexual acts were still illegal in the United Kingdom. He accepted treatment with female hormones (chemical castration) as an alternative to prison. He died in 1954, several weeks before his 42nd birthday, fromcyanide poisoning.

An inquest determined it was suicide; his mother and some others believed his death was accidental. On 10 September 2009, following an Internet campaign, British Prime Minister Gordon Brown made an official public apology on behalf of the British government for the way in which Turing was treated after the war.