Knowledge Update

​London, May 29 (IANS) A team of archaeologists has scanned the highest prehistoric paintings of animals in Europe discovered in a rock shelter in the French Alps 2,133 metres above sea level.

The team from the University of York used car batteries to power laser and white-light scanners in a logistically complex operation to reveal the rock paintings of Abri Faravel that were discovered in 2010.

The rock shelter has seen phases of human activity from the Mesolithic to the medieval period, with its prehistoric rock paintings known to be the highest painted representations of animals (quadrupeds) in Europe.

Researchers recently published the scans in online journal Internet Archaeology.

"After years of research in this valley, the day we discovered these paintings was undeniably the highlight of the research programme," said project lead Kevin Walsh from University of York. 

"As this site is so unusual, we made the decision to carry out a laser-scan of the rock shelter and the surrounding landscape, plus a white-light scan of the actual paintings," he added. 

The scanning was logistically complex as the only source of electricity was car batteries, which, along with all of the scanning equipment, had to be carried up to the site. 

"This is the only example of virtual models, including a scan of the art, done at high altitude in the Alps and probably the highest virtual model of an archaeological landscape in Europe," Walsh said.

The project was part of a study that investigates the development of human activity over the last 8,000 years at high altitude in the southern Alps.

Artefacts found in Abri Faravel also include Mesolithic and Neolithic flint tools, Iron Age hand-thrown pottery, a Roman fibula and some medieval metalwork.

However, the paintings are the most unique feature of the site, revealing a story of human occupation and activity in one of the world's most challenging environments from the Mesolithic to post-Medieval period.

​London, May 30 (IANS) Even if comets did not play as big a role in delivering water as once thought to the Earth they certainly had the potential to deliver the ingredients of life, new research has found.

The possibility that water and organic molecules were brought to the early Earth through impacts of objects like asteroids and comets have long been the subject of debate.

The European Space Agency's (ESA) Rosetta probe has now shown a significant difference in composition between Comet 67P/C-G's water and that of Earth.

“The multitude of organic molecules already identified by ROSINA, now joined by the exciting confirmation of fundamental ingredients like glycine and phosphorus, confirms our idea that comets have the potential to deliver key molecules for prebiotic chemistry," explained Matt Taylor, Rosetta project scientist of the European Space Agency (ESA).

While more than 140 different molecules have already been identified in the interstellar medium, amino acids could not be traced. 

However, hints of the amino acid glycine, a biologically important organic compound commonly found in proteins, were found during NASA's Stardust mission that flew by “Comet Wild 2” in 2004.

Now, for the first time, repeated detections at a comet have been confirmed by Rosetta in Comet 67P/C-G's fuzzy atmosphere or coma.

“This is the first unambiguous detection of glycine in the thin atmosphere of a comet," says Kathrin Altwegg, principal investigator of the ROSINA instrument at University of Bern. 

At the same time, the researchers also detected the organic molecules methylamine and ethylamine which are precursors to forming glycine. 

Unlike other amino acids, glycine is the only one that has been shown to be able to form without liquid water. 

"The simultaneous presence of methylamine and ethylamine, and the correlation between dust and glycine, also hints at how the glycine was formed," Altwegg noted.

Another exciting detection by ROSINA made for the first time at a comet is of phosphorus. 

It is a key element in all living organisms and is found in the structural framework of DNA and RNA.

“Demonstrating that comets are reservoirs of primitive material in the solar system and vessels that could have transported these vital ingredients to Earth is one of the key goals of the Rosetta mission, and we are delighted with this result,” Taylor pointed out in a paper forthcoming in the journal Science.​

​Sydney, May 27 (IANS) In a finding that could lead to new drugs to treat cancer and autoimmune diseases, researchers, including one of Indian-origin, have discovered a new way of triggering cell death.

Programmed cell death, also called apoptosis, is a natural process that removes unwanted cells from the body. Failure of apoptosis can allow cancer cells to grow unchecked or immune cells to inappropriately attack the body.

The protein known as Bak is central to apoptosis. In healthy cells Bak sits in an inert state but when a cell receives a signal to die, Bak transforms into a killer protein that destroys the cell.

In this study, researcher Sweta Iyer from the Walter and Eliza Hall Institute of Medical Research, Victoria, and colleagues discovered a novel way of directly activating Bak to trigger cell death. 

The researchers discovered that an antibody they had produced to study Bak actually bound to the Bak protein and triggered its activation.

"We were excited when we realised we had found an entirely new way of activating Bak," said Ruth Kluck who is also from Walter and Eliza Hall Institute of Medical Research in Australia.

The researchers hope to use this discovery to develop drugs that promote cell death.

"There is great interest in developing drugs that trigger Bak activation to treat diseases such as cancer where apoptosis has gone awry," she said. 

"This discovery gives us a new starting point for developing therapies that directly activate Bak and cause cell death," Kluck pointed out.

The researchers used information about Bak's three-dimensional structure to find out precisely how the antibody activated Bak.

The study was published in the journal Nature Communications.

"The advantage of our antibody is that it can't be 'mopped up' and neutralised by pro-survival proteins in the cell, potentially reducing the chance of drug resistance occurring," Kluck said.​

​New York, May 27 (IANS) Researchers, including one of Indian-origin, have discovered that lower levels of a hormone may make teenagers vulnerable to gaining unhealthy weight.

"Our study is the first to look at levels of spexin in the pediatric population," said one of the study authors Seema Kumar from Mayo Clinic Children's Centre in Minnesota, US. 

Potentially tied to weight management, spexin is also believed to have a role in controlling arterial blood pressure as well as salt and water balance.

"Previous research has found reduced levels of this hormone in adults with obesity. Overall, our findings suggest spexin may play a role in weight gain, beginning at an early age," she added.

The study was published in the Journal of Clinical Endocrinology & Metabolism.

The study analysed spexin levels in 51 obese and 18 teenagers of normal weights between ages 12 and 18. The participants had blood samples taken between 2008 and 2010 as part of separate clinical trials.

Researchers tested the blood samples to measure spexin levels. They divided the teenagers into four groups based on their spexin levels. 

Among the participants with the lowest levels of spexin, the odds of having obesity were a little more than five times higher than in the group with the highest levels of the hormone.

"It is noteworthy that we see such clear differences in spexin levels between obese and normal weight adolescents," Kumar said. 

"Since this is a cross-sectional study, more research is needed to explore the physiological significance of spexin, how it may be involved in the development of childhood obesity, and whether it can be used to treat or manage the condition," she added.​

​New York, May 27 (IANS) In order to help you identify between habitual and goal-directed action, your brain's circuits compete for control and make a fine balance between the two actions, an international team of researchers has identified.

They found brain chemicals and neural pathway involved in switching between habitual behaviour and deliberate decision-making -- providing the strongest evidence to date that the brain's circuits for habitual and goal-directed action compete for control. 

"We need a balance between habitual and goal-directed actions. For everyday function, we need to be able to make routine actions quickly and efficiently, and habits serve this purpose," said lead author Christina Gremel from the University of California-San Diego.

"However, we also encounter changing circumstances, and need the capacity to 'break habits' and perform a goal-directed action based on updated information. When we can't, there can be devastating consequences," she added.

The study, published recently in the journal Neuron, worked with a mouse model to demonstrate what happens in the brain for habits to control behaviour.

Gremel said the brain's circuits for habitual and goal-directed action compete for control -- in the orbitofrontal cortex (OFC), a decision-making area of the brain -- and that neurochemicals called endocannabinoids allow for habit to take over, by acting as a sort of brake on the goal-directed circuit.

"Habit takes over when the OFC is quieted," Gremel said.

In the study, since endocannabinoids are known to reduce the activity of neurons in general, the researchers hypothesised that endocannabinoids may be quieting or reducing activity in the OFC and, with it, the ability to shift to goal-directed action. 

They trained mice to perform the same lever-pressing action for the same food reward but in two different environments that differentially bias the development of goal-directed versus habitual actions. 

Like humans who don't suffer from neuropsychiatric disorders, healthy mice readily shifted between performing the same action using a goal-directed versus habitual action strategy. 

To test their hypothesis on the role played by endocannabinoids, the researchers then deleted a particular endocannabinoid receptor. 

Mice missing these receptors did not form habits -- showing the critical role played by the neurochemicals as well as that particular pathway.​

​New York, May 27 (IANS) As the difficulty of making a decision increases, activity in a part of the brain that is crucial to making coherent thoughts also increases, a study says.

Researchers found a strong positive correlation between perceptual difficulty and activity in insular cortex which is generally divided into anterior insula, middle insula, and a posterior insula.

Perceptual decision-making is the process in which sensory information is gathered and used to influence our behaviour. For instance, if a person is driving and suddenly sees an object in front of the vehicle, he or she must decide what action to take, such as whether to slow down or bypass the object.

"This study found the activity of the anterior insulae can predict how well the sensory information is perceived or what the difficulty level of the perceptual task is," said Mukesh Dhamala, associate professor at Georgia State University in the US.

"This research is important because the anterior insulae, along with two nearby brain structures, make up the salience network, and when this network is impaired, it affects the ability to switch between tasks and make coherent thoughts,” Dhamala noted.

“Impairment in this network could possibly be linked to psychiatric illnesses, such as schizophrenia, dementia and autism, so it's essential to learn more about how this brain area should be functioning," he explained.

The findings were reported in the journal Neuroscience.

The study involved 33 people with normal or corrected-to-normal vision and normal neurological history. 

They completed four tasks, in which the researchers manipulated the visual and audiovisual stimuli to create varying degrees of task difficulty.

In all four experimental tasks, researchers found that anterior insulae activity consistently increased with task difficulty.

​London, May 27 (IANS) Have you ever wondered why any talk of giving money to the unemployed often triggers a political storm whereas increase in healthcare costs often earn laurels? The answer, say researchers, can be found deep in our psychology, where powerful intuitions lead us to view illness as the result of bad luck and worthy of help.

People intuitively believe that those who fall ill are unlucky, while unemployed people have brought it on themselves, the study found.

Using techniques to uncover people's implicit intuitions, the researchers explored the fundamental differences behind our attitudes towards unemployment benefits and healthcare.

According to the researchers, the differences may be found in the evolutionary history of our species.

Unemployment came about as a result of the industrialisation, while illness is something the human species has faced for millions of years. 

"For millions of years, a need for health care reflected accidents such as broken legs or random infections. Evolution could therefore have built our psychology to think about illnesses in this way, as something we have no control over,” said one of the researchers Michael Bang Petersen, professor in political science at Aarhus University in Denmark.

“People everywhere seem to have this deep-seated intuition that ill people are unfortunate and deserve to be helped," he noted.

The researchers did research in Denmark, the US and Japan and found that everywhere people intuitively believed that people who fall ill are unlucky, while unemployed people have brought it on themselves.

"When it comes to healthcare, everyone seem united in the belief that people who are ill are unlucky and need help,” he said.

The findings appeared in the American Journal of Political Science.

“This means that the policies in the areas of health care and unemployment are very different, as we all more or less agree on the goal in healthcare, while we deeply disagree on whether or not unemployed people deserve help," the researcher said.​

​New York, May 27 (IANS) A team of students has developed an early version of a foot that enables women adjusting to life with a prosthetic limb to wear heels up to four inches high.

"High heels have become an integral part of the female lifestyle in modern society, permeating through all aspects of life -- professional and social," said the authors from Johns Hopkins University who made the prosthetic foot as part of their final senior project in mechanical engineering. 

"For female veterans of the US armed services with lower limb amputations, that seemingly innocuous but so pervasive and decidedly feminine part of their lives is gone," they added.

So, they took up the challenge of creating a foot that adjusts without a separate tool to a range of heel heights, holds position without slipping, supports up to 250 pounds or 114 kg, weighs less than three pounds or 1.3 kg and, of course, is slender enough to accommodate a woman's shoe.

They tried a balloon in the heel to give it spring or "energy return", as engineers say. That didn't work. 

They tried a mousetrap spring but that didn't work either. Then they tried a sideways sandwich of 23 slender titanium plates to form the foot itself but that was too heavy and not springy. 

A 20-layer carbon fibre footplate failed a stress test, but a 28-layer version worked, forming the base of the foot which the team now calls the "Prominence".

They built a heel-adjustment mechanism with two interlocking aluminum disks. It opens and closes with an attached lever at the ankle. 

For the ankle, they used an off-the-shelf hydraulic unit that enables a smooth gait and flexing at the sole.

Alexandra Capellini, a Johns Hopkins University junior who lost her right leg to bone cancer as a child, tried the foot with a flat shoe and liked it.

The design is still in progress. It will take time to assess the commercial appeal and potential of the "Prominence", including the question of whether anything the team created could qualify for a patent.​

​New York, May 28 (IANS) People have always wondered why many birds lay bright blue eggs. Researchers have now shown that the colour could protect the embryo from harmful sunlight, including dangerous ultraviolet (UV) radiation.

David Lahti of the City University of New York and Dan Ardia of Franklin & Marshall College tested the hypothesis that pigmentation might help an egg strike a balance between two opposing and potentially damaging effects of the sun - light transmission into light-coloured eggs, and heating up of dark-coloured eggs. 

As predicted, more intensely blue eggshells shielded the interior from light, including dangerous UV radiation, but more intense colour also caused eggs to absorb more light and heat up, which can be even more dangerous in brighter environments. 

These two patterns - termed by the authors "pigment as parasol" and the "dark car effect" --combined with a knowledge of the nesting behaviour and habitats of birds, can lead to predictions as to why the eggs of some birds vary across species from blue to white. 

Darker eggs are predicted in moderate light to shield the embryo, but in brighter nests the dangers of egg heating predict lighter coloured eggs. 

Whereas camouflage from predators is still probably the single most important factor governing the evolution of dull and mottled egg colours, for the brighter colours the biophysical evidence points to the sun, the study said.

The findings appeared in the journal The American Naturalist.​

​Beijing, May 29 (IANS) China will launch its first experimental quantum communication satellite in July, according to the Chinese Academy of Sciences (CAS) on Friday.

This will be the first quantum communication through a satellite in the world, Xinhua news agency quoted Pan Jianwei, professor with University of Science and Technology of China as saying.

Quantum communication boasts ultra-high security as a quantum photon can neither be separated nor duplicated. It is hence impossible to wiretap, intercept or crack the information transmitted through it, said Pan.

Chinese scientists have taken five years to develop and manufacture the first quantum satellite. It will be transported to Jiuquan Satellite Launch Center in June, according to the CAS. ​