Knowledge Update

London, May 19 (IANS) Current rates of climate change could trigger instability in a major Antarctic glacier, ultimately leading to nearly three metre rise of the sea level, say researchers.

The scientists looked at the future of Totten glacier, a significant glacier in Antarctica that drains one of the world's largest areas of ice, on the East Antarctic Ice Sheet (EAIS).

By studying the history of Totten's advances and retreats, the researchers discovered that if climate change continues unabated, the glacier could cross a critical threshold within the next century, entering an irreversible period of very rapid retreat.

This would cause it to withdraw up to 300 kilometres inland in the following centuries and release vast quantities of water, contributing up to 2.9 metres to global sea-level rise.

"The evidence coming together is painting a picture of East Antarctica being much more vulnerable to a warming environment than we thought," said study co-author Martin Siegert, professor at Imperial College London.

"This is something we should worry about. Totten Glacier is losing ice now, and the warm ocean water that is causing this loss has the potential to also push the glacier back to an unstable place," Siegert noted.

The East Antarctic Ice Sheet is currently thought to be relatively stable in the face of global warming compared with the much smaller ice sheet in West Antarctica, but Totten Glacier is bucking the trend by losing substantial amounts of ice. 

The new research revealed that Totten Glacier may be even more vulnerable than previously thought.

The findings were published in the journal Nature. 

To uncover the history of Totten Glacier's movements, the team looked at the sedimentary rocks below the glacier using airborne geophysical surveys. 

From the geological record, influenced by the erosion by ice above, they were able to understand the history of the glacier stretching back millions of years.

The researcehrs found that the glacier has retreated more quickly over certain 'unstable' regions in the past. 

Based on this evidence, the scientists believe that when the glacier hits these regions again we will see the same pattern of rapid retreat.​

​Washington, May 19 (IANS) April 2016 was the 12th consecutive month a monthly global temperature record has been broken, the US government's climate agency said on Wednesday.

"This is the longest such balmy streak in the 137-year record, which dates back to 1880," Xinhua quoted the US National Oceanic and Atmospheric Administration (NOAA) as saying.

"The heat goes on -- and so do the records," the agency added.

For April, the average temperature across global land and ocean surfaces was 1.98 degrees Fahrenheit (1.10 degrees Celsius) above the 20th century average of 56.7 degrees Fahrenheit (13.7 degrees Celsius), according to the monthly report released by the NOAA.

This temperature departure from average was not only the highest for the month of April in the 1880-2016 record, but also the fourth-highest among all months on record, behind March 2016, February 2016, and December 2015, said the report.

On land, all six continents had at least a top nine warm April, with South America, Africa, and Asia observing a record high average temperature for April, the NOAA report said.

Only northeastern Canada and southern South America were cooler than average, with the most notable cool temperature departures across northeastern Canada.

Overall, "April 2016 was characterised by warmer to much warmer-than-average conditions across most of Earth's land surfaces," it concluded.

The globally averaged sea surface temperature for April was also highest for this month on record and surpassed the same period in 1998 by 0.43 degrees Fahrenheit (0.24 degrees Celsius) -- the last time a similar strength El Nino occurred.

This April also saw the the smallest Northern Hemisphere snow cover extent recorded in 50 years of snow-cover data collection.

For the four months of 2016, the average temperature for the globe was 2.05 degrees Fahrenheit (1.14 degrees Celsius) above the 20th-century average of 54.8 degrees Fahrenheit (12.7 degrees Celsius), the report added.​

Sydney, May 18 (IANS) Australian researchers have created a device that has set a new world record for solar efficiency, the media reported on Wednesday.

The device traps light through a simple prism, which dramatically bolsters the efficiency of solar cells, Xinhua news agency reported.

Researchers from the University of New South Wales (UNSW) Martin Green and Mark Keevers said the device extracts the maximum energy from sunlight, using a hybrid four-junction receiver to squeeze even more electricity from each beam of sunlight.

"This encouraging result shows there are still advances to come in photovoltaics research to make solar cells even more efficient," said Keevers.

"Extracting more energy from every beam of sunlight is critical to reducing the cost of electricity generated by solar cells as it lowers the investment needed, and delivering payback faster."

The pair set a new world record for sunlight-to-electricity conversion efficiency at 34.5 percent.

"What's remarkable is that this level of efficiency had not been expected for many years," said Green.

"A recent study by Germany's Agora Energiewende think tank set an aggressive target of 35 percent efficiency by 2050 for a module that uses unconcentrated sunlight, such as the standard ones on family homes."

The efficiency of commercially available solar panels is said to range between 14 to 22 percent.

"So things are moving faster in solar cell efficiency than many experts expected, and that's good news for solar energy," Green added.

"But we must maintain the pace of photovoltaic research in Australia to ensure that we not only build on such tremendous results, but continue to bring benefits back to Australia."​

​New York, May 18 (IANS) A genetic switch that is turned on in the brain during fasting helps halt the spread of intestinal bacteria into the bloodstream, says a new study.

The study shows a molecular pathway by which the brain communicates with the gastrointestinal (GI) tract to prevent unnecessary activation of the immune system during fasting by strengthening the barrier against gut microbes. 

The discovery of this brain-gut signal in fruit flies, which has many parallels to humans, could eventually inform the treatment of inflammatory bowel diseases in people, said the study published in the journal Proceedings of the National Academy of Sciences.

In addition to its role in promoting the absorption of nutrients from food, the GI tract is host to a panoply of bacteria. These microbes actually help in the digestive process by producing chemicals that break down complex fats and carbohydrates.

"Fasting has a positive value that spills over not just into the metabolic system, but also inflammation and brain function," said the study's lead investigator Marc Montminy, professor at Salk Institute for Biological Studies in La Jolla, California, US.

"Understanding how the gut maintains this barrier, and creating drugs to enhance that barrier, may have important benefits for people with inflammatory bowel disease," Montminy noted.

The new study is part of an ongoing research to pin down the mechanisms that a genetic switch in the brain called Crtc uses to control energy balance. ​

​Toronto, May 18 (IANS) Researchers, including one of Indian origin, have developed a device that can dramatically reduce the time and cost required for detecting the deadly E. coli bacteria in drinking water.

Some kinds of E. coli can cause diarrohea, while others cause urinary tract infections, respiratory illness and pneumonia, and other illnesses, according to the US Centres for Disease Control and prevention.

"We have developed a hydrogel based rapid E. coli detection system that will turn red when E. coli is present,” said Sushanta Mitra, professor at York University in Toronto.

"It will detect the bacteria right at the water source before people start drinking contaminated water,” Mitra said.

The new technology can cut down the time taken to detect E. coli from a few days to just a couple of hours. 

It is also an inexpensive way to test drinking water (Rs.155 per test estimated), which is a boon for many developing countries, the researchers said.

"This is a significant improvement over the earlier version of the device, the Mobile Water Kit, that required more steps, handling of liquid chemicals and so on,” Mitra noted.

"The entire system is developed using a readily available plunger-tube assembly. It’s so user-friendly that even an untrained person can do the test using this kit,” he added.

Traditional methods of testing for E. coli contamination involves collecting water samples to send to an appropriate microbiological lab where the bacteria is cultured before a plate count is done to detect E. coli presence.

The testing device uses the porous hydrogel matrix, developed by Mitra’s team at his Micro & Nano-scale Transport Laboratory that cages specific enzymatic substrates that release certain enzymes in E. coli cells. 

These enzymes then chemically react with the substrates to change colour. If there is no E. coli, the colour of the hydrogel won’t change, as there is no chemical reaction.

The results of the water test can be instantly broadcast using a mobile app already developed by the team​

​Washington, May 18 (IANS) Jupiter's moon Europa -- strongly believed to hide a deep ocean of salty liquid water beneath its icy shell -- can have the necessary balance of chemical energy for life even if the moon lacks volcanic hydrothermal activity, researchers have revealed.

Scientists at NASA's Jet Propulsion Laboratory (JPL), Pasadena, California, compared Europa's potential for producing hydrogen and oxygen with that of Earth through processes that do not directly involve volcanism.

The balance of these two elements is a key indicator of the energy available for life.

The study found that the amounts would be comparable in scale. On both worlds, oxygen production is about 10 times higher than hydrogen production.

The work draws attention to the ways that Europa's rocky interior may be much more complex and possibly Earth-like than people typically think.

“We're studying an alien ocean using methods developed to understand the movement of energy and nutrients in Earth's own systems. The cycling of oxygen and hydrogen in Europa's ocean will be a major driver for Europa's ocean chemistry and any life there, just it is on Earth,” explained Steve Vance, planetary scientist at JPL and lead author.

As part of the study, the researchers calculated how much hydrogen could potentially be produced in Europa's ocean as seawater reacts with rock in a process called serpentinisation.

In this process, water percolates into spaces between mineral grains and reacts with the rock to form new minerals, releasing hydrogen in the process.

New cracks expose fresh rock to seawater, where more hydrogen-producing reactions can take place.

In Earth's oceanic crust, such fractures are believed to penetrate to a depth of five-six kms.

On present-day Europa, the researchers expect water could reach as deep as 25 kms into the rocky interior, driving these key chemical reactions throughout a deeper fraction of Europa's seafloor.

The other half of Europa's chemical-energy-for-life equation would be provided by oxidants -- oxygen and other compounds that could react with the hydrogen -- being cycled into the Europan ocean from the icy surface above.

“The oxidants from the ice are like the positive terminal of a battery, and the chemicals from the seafloor, called reductants, are like the negative terminal," noted Kevin Hand, planetary scientist at JPL.

“Whether or not life and biological processes complete the circuit is part of what motivates our exploration of Europa,” he added in a new paper published in Geophysical Research Letters, a journal of the American Geophysical Union.

Europa's rocky, neighbouring Jovian moon “Io” is the most volcanically active body in the solar system.

Scientists have long considered it possible that Europa might also have volcanic activity, as well as hydrothermal vents, where mineral-laden hot water would emerge from the sea floor.

NASA is currently formulating a mission to explore Europa and investigate the moon's potential habitability.​

London, May 18 (IANS) Based on the "liquid wire" technique in spider webs, a team of international researchers has created composite fibers which extend like a solid and compress like a liquid.

Pulling on a sticky thread in a garden spider's orb web and letting it snap back reveals that the thread never sags but always stays taut, even when stretched to many times its original length.

This is because any loose thread is immediately spooled inside the tiny droplets of watery glue that coat and surround the core gossamer fibres of the web's capture spiral.

The study, which was carried out by researchers from the University of Oxford and the Pierre and Marie Curie University, Paris, was published by the University of Oxford in the journal Proceedings of the National Academy of Sciences.

"Surprisingly, each drop packs enough punch in its watery skins to reel in loose bits of thread. And this winching behaviour is used to excellent effect to keep the threads tight at all times, as we can all observe and test in the webs in our gardens," said Prof. Fritz Vollrath form the University of Oxford.

The novel properties observed and analysed by the researchers rely on a subtle balance between fibre elasticity and droplet surface tension. The team was also able to recreate this technique in the laboratory using oil droplets on a plastic filament.

This artificial system behaved just like the spider's natural winch silk, with spools of filament reeling and unreeling inside the oil droplets as the thread extended and contracted, according to the study.

"Our bio-inspired hybrid threads could be manufactured from virtually any components. These new insights could lead to a wide range of applications, such as micro-fabrication of complex structures, reversible micro-motors, or self-tensioned stretchable systems," said Herve Elettro, the first author of the study and a doctoral researcher from the Pierre and Marie Curie University.​

​London, May 18 (IANS) A study has found a new link between inflammation and cell division -- two of the most important processes in the human body whose accurate control is a holy grail for scientists researching the prevention of infection, inflammatory disease and cancer.

"This is an exciting discovery: for the first time we find a link between the system which regulates how cells divide and the basis of some of medicine's most intractable diseases," said Mike White, who led the joint study by the University of Manchester and Liverpool. 

Inflammatory signals produced by a wound or during an infection can activate a protein called Nuclear Factor-kappaB (NF-kB), which controls the activity of genes that allow cells to adapt to the situation.

Incorrect control of NF-kB is associated with inflammatory diseases, such as Crohn's disease, psoriasis and rheumatoid arthritis. It has also been linked with ageing and some cancers.

A key way in which human cells adapt to signals in their environment is by dividing to produce new cells through a repeating pattern of events, called the cell cycle. A cell first makes copies of its DNA, in a stage known as the DNA synthesis phase, and then divides into two daughter cells.

The cell cycle is controlled by a family of proteins called E2 factors, which control the start of the new cell's DNA synthesis phase.

The study published recently in the journal eLife showed that the NF-kB and E2 factors bind to each other in the cell. This controls the level of the NF--kB signal, which is enhanced just before DNA synthesis, but reduced during the DNA synthesis phase.

Scientists also showed that signals which activate NF-kB can change the timing of cell division.

The findings suggest that direct interactions between E2 factor proteins and NF-kB enable cells to decide whether to divide and determine how they react in different ways to inflammatory signals.​

New York, May 18 (IANS) A skull condition that has been believed to be a thing of the past due to poor diet among our ancestors not only still exists, but is fairly common among modern humans, new research has found.

The skull condition called cribra orbitalia (CO) makes bone inside the eye sockets porous. It is not known to cause any adverse health effects, but is generally regarded as being caused by iron deficiency anemia.

The condition has traditionally been used by anthropologists to assess diet and health in prehistoric populations. 

For example, the presence of CO could tell researchers that a population was not getting a sufficiently varied diet.

"But there's been a lot of debate about the prevalence of CO in modern populations, with some saying it had effectively disappeared," said study co-author Ann Ross from North Carolina State University in the US.

"We wanted to know if CO was still extant and, if so, how common it is in modern populations, relative to earlier eras," Ross noted.

For this study, the researchers looked at modern, historic and prehistoric human remains from South Africa, North America.

Altogether, the researchers evaluated data on 844 skulls -- 245 prehistoric, 381 historic (as recent as the early 20th century) and 218 modern.

The researchers found that CO was not only present in modern populations, but that it was not even uncommon.

For example, the researchers found that two of the five modern North American juvenile skulls evaluated in the study - 40 percent - had CO. And 15 of the 60 South African juveniles evaluated in the study - 25 percent - had CO.

Overall, the researchers found that 12.35 percent of modern North Americans and 16.8 percent of modern South Africans, across all age groups, had CO.

Both rates are higher than their historic counterparts. Only 2.23 percent of historic South African skulls evaluated had CO, and only 6.25 percent of historic North American skulls. Even the prehistoric North American skulls had a lower rate of CO, at 11.86 percent.

The study was published online in the journal Clinical Anatomy.

"We think the increased prevalence of CO in the modern skulls may be due to intestinal parasites in some populations and iron-poor diet," Ross noted.

"These findings drive home the fact that disadvantaged socioeconomic groups, and parts of the developing world, are still struggling with access to adequate nutrition," Ross added.​

​Toronto, May 17 (IANS) Children and young adults take a long time to fully recover from any brain injury occurring while playing games, says a study.

The findings of the Canadian study indicate that those in the age group of eight to 16 are not only vulnerable to concussions but -- because their brain is still developing -- they are neurologically more fragile than adults for performing tasks that require cognitive motor integration following a concussion.

After a concussion, young athletes usually rejoin their teams in a few weeks if they do not have any active symptoms. 

“However, they may take up to two years to fully recover from the injury before they can play as skillfully as their teammates with no history of concussion," said Lauren Sergio from York University in Canada.

"Performing motor tasks, guided by what we see, is crucial in skill-based activities such as sports," Sergio added in the paper published in the journal Concussion. 

The team analysed the prolonged difficulty in cognitive-motor integration in 50 children and adolescents with a history of concussion and were compared with 49 who have never had a concussion.

The participants in both the groups were asked to perform two different tasks on a dual-touchscreen laptop. 

In one task, target location and motor action were aligned. In the other task that tested cognitive-motor integration, the required movement was not aligned with the guiding visual target and required simultaneous thinking for successful performance.

"We noticed significant difficulty in completing the tasks among those with concussion history," said lead author Marc Dalecki.

"In fact, it took many of the children two years after the concussion to have a similar performance on the task as children who did not have a history of concussion," Dalecki noted.

"The current return to sport assessment doesn't test to see if the injured person has regained this ability. Because of this, often children and youth who have had a concussion end up returning to normal activities before they are fully recovered which makes them more vulnerable to another concussion," Sergio said.​