Knowledge Update

Washington, Nov 11 (IANS) In a first-of-its-kind collaboration, NASA's Spitzer and Swift space telescopes joined forces to reveal a brown dwarf - thought to be the missing link between planets and stars, with masses up to 80 times that of our solar system's most massive planet, Jupiter.

The discovery of this brown dwarf, with the unwieldy name OGLE-2015-BLG-1319, marks the first time two space telescopes have collaborated to observe a microlensing event -- when a distant star brightens due to the gravitational field of at least one foreground cosmic object, NASA said in a statement on Thursday.

"We want to understand how brown dwarfs form around stars, and why there is a gap in where they are found relative to their host stars," said Yossi Shvartzvald from NASA's Jet Propulsion Laboratory, Pasadena, California, and lead author of a study published in the Astrophysical Journal. 

Spitzer and Swift observed the microlensing event after being tipped off by ground-based microlensing surveys, including the Optical Gravitational Lensing Experiment (OGLE). 

By combining data from these space-based and ground-based telescopes, researchers determined that the newly discovered brown dwarf is between 30 and 65 Jupiter masses.

They also found that the brown dwarf orbits a K dwarf, a type of star that tends to have about half the mass of the sun. 

"In the future, we hope to have more observations of microlensing events from multiple viewing perspectives, allowing us to probe further the characteristics of brown dwarfs and planetary systems," co-author of the study Geoffrey Bryden Jet Propulsion Laboratory.

​Tokyo, Nov 11 (IANS) More than half of Japan's largest coral reef has been destroyed due to the rise in water temperatures this year, says a study released by the Ministry of Environment on Friday.

The reef, located in front of Ishigaki island in Okinawa and protected as a natural reserve, boasts over 70 coral species and is considered one of the oldest and largest in the northern hemisphere, Efe news reported.

Ninety-seven per cent of the corals have undergone bleaching and 56 per cent have died, according to the ministry study which analysed the reef between September and October.

The deterioration was attributed to the 2 degree Celsius rise in average water temperatures in the area and the ministry warned that the remaining corals are at risk of disappearing in these conditions.

The meteorological phenomenon of El Nino, which causes temperatures of the sea surface to rise, has contributed to the coral bleaching around the world this year, including some of the largest protected reefs in Australia, Thailand and Maldives.

Coral bleaching occurs when they are faced with constant and extreme changes of temperature, light and nutrients.

This process puts at risk the abundance of fish species that depend on the reefs for their shelter and food.

In the Indian and Pacific oceans, if greenhouse gas emissions continue at the current level, fish stocks could diminish between 10 and 30 per cent by 2050 compared to the 1970-2000 period, according to data from the International Union for Conservation of Nature. 

​New York, Nov 11 (IANS) Researchers have reported the discovery of a smart material that can be applied to any surface to repel ice and which "outperforms all others currently in use".

"Anti-icing surfaces have a critical footprint on daily lives of humans ranging from transportation systems and infrastructure to energy systems, but creation of these surfaces for low temperatures remains elusive," the researchers wrote. 

"Non-wetting surfaces and liquid-infused surfaces have inspired routes for the development of icephobic surfaces. However, high freezing temperature, high ice adhesion strength, and high cost have restricted their practical applications," the study said.

The new material, known as a magnetic slippery surface (MAGSS), was described in the journal Nature Communications.

Among the advantages of the new material is that it has a far lower freezing threshold than the best icephobic technology currently available, said principal investigator for the research Hadi Ghasemi, Assistant Professor at University of Houston in the US. 

"These new surfaces provide the path to tackle the challenge of icing in systems, thereby improving the quality of human life," he said.

Potential applications range from the aircraft industry -- planes can encounter freezing rain or super-cooled water droplets while flying, leading to a buildup of ice and, potentially, a crash -- to the power industry, where icing can cause power poles, towers and transmission lines to collapse.

These surfaces promise a new paradigm for development of icephobic surfaces in aviation technologies, ocean-going vessels, power transmission lines and wind turbines in extreme environments, the researchers wrote.

While one side of the surface is coated with a magnetic material, a thin layer of magnetic fluid -- a mixture of fluid and iron oxide nanoparticles -- is deposited on the other side, Ghasemi said.

The magnetic fluid faces outside. When a droplet of water hits the surface, the magnetic fluid acts as a barrier, stopping the droplet from reaching the solid surface.

"There's no adhesion of the ice to the solid surface, so it basically slides off the surface," he said.

Ultimately, Ghasemi said he hopes to develop the coating as a spray that can be applied to any surface. 

​London, Nov 11 (IANS) Researchers at the University of Oxford have developed a new, portable breath analyser that could someday help doctors diagnose diabetes without painful pinpricks, needles or other unpleasant methods.

Many studies examining the hallmarks of diabetes in exhaled breath have shown that elevated levels of acetone are strongly linked to diabetes. 

Detecting the concentrations of any given substance in breath in a simple way, however, is a major challenge. 

Breath contains a complex mix of compounds, including water, carbon dioxide and methane, that can throw results off. 

A technique called mass spectrometry can do the job, but it is not very practical for point-of-care testing. 

Robert Peverall from University of Oxford and colleagues wanted to fill that void.

The researchers created a hand-held device with an adsorbent polymer that can trap acetone from exhaled breath, then release it into a cavity where a laser probes its concentration. 

"The device features a seven cm long high finesse optical cavity as an optical sensor that is coupled to a miniature adsorption preconcentrator containing 0.5 g of polymer material," the researchers said.

They tested the accuracy of the device on the breath of healthy participants under different conditions, such as after overnight fasting or exercising, and compared results with mass spectrometry readings. 

The measurements were a close match and covered a wide range of concentrations, including those that would suggest a patient has undiagnosed Type-1 diabetes, or has problems controlling their blood glucose, said the study published in the American Chemical Society's journal Analytical Chemistry.

Adding to the practicality of the device, the researchers said it could be re-used many times.

​Beijing, Nov 11 (IANS) Scientists have discovered a dinosaur fossil -- nicknamed the 'Mud Dragon' -- that can help them better understand how the last-surviving dinosaurs were flourishing before their mass extinction.

'Mud Dragon', which meant 'muddy dragon on the road to heaven', was a bird-like species, discovered from a building site near Ganzhou in China. 

According to the study published in journal Scientific Reports, the two-legged animal belonged to a family of feathered dinosaurs called oviraptorosaurs. They were characterised by having short, toothless heads and sharp beaks.

"This new dinosaur is one of the most beautiful, but saddest, fossils. Its skeleton is one of the best examples of a dinosaur that was flourishing during those final few million years before the asteroid came down and changed the world in an instant," said Steve Brusatte of the University of Edinburgh in Scotland.

Fossil discoveries in recent decades suggest that this group of flightless animals were experiencing a numbers boost, diversifying into new species, during the 15 million years before the dinosaurs went extinct, the researchers noted. 

Further, the study showed that it was probably one of the last groups of dinosaurs to diversify before the asteroid impact 66 million years ago, which killed off all of the non-bird dinosaurs.

The fossil remains was remarkably well preserved and almost intact, lying on its front with its wings and neck outstretched.

According to scientists, the creature may have died in this pose after becoming mired in mud about 66-72 million years ago.

​New York, Nov 11 (IANS) Researchers from the University of Missouri School of Medicine has come out with a new test to check eye pressure to prevent possible vision loss.

The most common complication from cataract surgery is high eye pressure, which can cause swelling and other issues that can lead to vision loss or even blindness. 

"The current standard of care following cataract surgery is to refill the eye with a saline solution and tap on the eye with a Q-tip to observe if it is too firm, too soft or just right," said John Jarstad, Associate Professor at the University of Missouri School of Medicine in a statement.

"This Goldilocks-style guesstimate often is inaccurate, and patients might actually have higher eye fluid pressure than the surgeon believes. We use a device known as a tonometer to accurately gauge eye pressure," Jarstad added.

An electronic eye pressure monitoring device known as a tonometer often is used in a clinical setting to determine eye pressure, but the device rarely is used in a surgical setting. 

The researchers studied 170 patients who had eye pressure adjusted after cataract surgery with a tonometer and found that patients were 2.5 to 4 times less likely to develop cystoid macular edema -- cyst-like pockets of fluid in the macula of the eye.

According to the researchers, normal eye pressure should be between 16 and 21 mmHg, or millimeters of mercury.

In most cases, a high eye pressure will resolve itself in a matter of days without issue, but in cases in which the pressure is significantly high, a person can experience symptoms of nausea and pain above the eyebrow.

In these cases, it's important that the pressure be adjusted to prevent permanent damage to the eye, the study suggested.

"I recommend eye surgeons adopt this practice for the good of their patients. There is no additional cost to patients, and if it saves just one patient from going blind, it would be well worth every doctor using it in his or her surgical practice," the researcher said

New York, Nov 11 (IANS) In a major breakthrough, a team of researchers, including one of Indian origin, has identified two chemicals that can help develop heart cells that can beat harder, faster and stronger, bringing technology one step closer to regenerating damaged hearts.

Scientists from Gladstone Institute of Cardiovascular Disease, in San Francisco, US, tested 5,500 chemicals, and identified two that can potentially transform a scar tissue into healthy beating heart muscle -- a discovery that can help find new and effective treatments for heart failure. 

The two chemicals increased eightfold the number of heart cells created, as well as sped up the process of cell conversion, achieving in one week what used to take six to eight weeks, the study said.

"The study discovered that chemically inhibiting two biological pathways active in embryonic formation improves the speed, quantity, and quality of the heart cells produced from our original process," said senior author Deepak Srivastava, Director of the Gladstone Institute of Cardiovascular Disease. 

After suffering a heart attack, the connective tissues develop scar tissue, which then contribute to heart failure.

When the heart muscle gets damaged, the body is unable to repair the dead or injured cells.

According to researchers, the first chemical inhibits a growth factor that helps cells grow and divide and is important for repairing tissue after injury. 

The second chemical inhibits an important pathway that regulates heart development. 

By combining the two chemicals with the current method -- of reprogramming connective tissue cells into heart muscle cells using certain proteins -- the researchers successfully regenerated heart muscle and greatly improved heart function in mice that had suffered a heart attack.

In addition, the chemicals were also used to improve direct cardiac reprogramming of human cells, which is a more complicated process that requires additional factors, the researchers noted in the paper published in the journal Circulation.

London, Nov 10 (IANS) Scientists have for the first time used a neural prosthetic to restore walking movement directly to the legs of non-human primates.

In the study, the researchers from Brown University in Rhode Island, US, used a wireless "brain-spinal interface" to bypass spinal cord injuries in a pair of rhesus macaques, restoring intentional walking movement to a temporarily paralysed leg. 

Walking is made possible by a complex interplay among neurons in the brain and spinal cord. 

Electrical signals originating in the brain's motor cortex travel down to the lumbar region in the lower spinal cord, where they activate motor neurons that coordinate the movement of muscles responsible for extending and flexing the leg.

To calibrate the decoding of brain signals, the researchers implanted the brain sensor and wireless transmitter in healthy macaques. The signals relayed by the sensor could then be mapped onto the animals' leg movements. 

They showed that the decoder was able to accurately predict the brain states associated with extension and flexion of leg muscles.

"The system we have developed uses signals recorded from the motor cortex of the brain to trigger coordinated electrical stimulation of nerves in the spine that are responsible for locomotion," said David Borton, Assistant Professor at Brown University.

The study, published in the Journal Nature, suggests that a brain-controlled spinal stimulation system may enhance rehabilitation after a spinal cord injury.

New York, Nov 10 (IANS) Researchers have identified a gene -- previously known only to regulate bone growth and muscle metabolism in mammals -- that can also act as a promoter of brain maturation, cognition and learning in human and non-human primates.

The findings showed that osteocrin -- a gene found in the skeletal muscles of all mammals -- is completely turned off in rodent brains yet highly active in the brains of non-human primates and humans.

However, the activity of the gene was most intense in neurons of the neocortex, the topmost layer of cells covering the brain and responsible for higher-level cognition, such as long-term memory, thought and language. 

At the same time, osteocrin was noticeably absent from other parts of the brain responsible for non-cognitive functions such as spatial navigation, balance, breathing, heart rate and temperature control.

This suggests a possible role of the gene in the development of cognition -- a cardinal feature that distinguishes the brains of human and non-human primates from those of other mammals, the researchers said.

"We have uncovered what we believe is a critical clue into the evolution of the human brain, one that gives us a glimpse into the genetic mechanisms that may account for differences in cognition between mice and humans," said Michael Greenberg, Professor at the Harvard Medical School, in Boston, US.

Further analysis revealed that osteocrin's activation curbed the growth of neuronal dendrites -- branchlike projections responsible for transmitting signals from one brain cell to the next.

"Restricting dendritic growth is a precision-enhancing mechanism, essential to ensuring that neuronal wires don't get crossed and compromise signal transmission from one cell to the next," added Bulent Ataman, neurobiologist at the Harvard Medical School.

This observation suggests that osteocrin's activity may help enhance nerve cell agility and proper signal transmission to ensure robust communication across neurons, Ataman said.

For their experiments, published in the journal Nature, the team analysed RNA levels -- the molecular footprints of gene activity -- in the brain cells of mice, rats and humans. 

​New York, Nov 10 (IANS) The Indian Ocean's Agulhas Current -- one of the strongest currents in the world -- is getting wider rather than strengthening, which will have important implications for global climate change, a study says.

The findings suggest that intensifying winds in the region may be increasing the turbulence of the current, rather than increasing its flow rate.

"To find decades of broadening, rather than intensification, profoundly impacts our understanding of the Agulhas Current and its future role in climate change," said study co-author Shane Elipot of the University of Miami's Rosenstiel School of Marine and Atmospheric Science in the US.

The Agulhas Current flows along the east coast of South Africa, transporting warm, salty water away from the tropics toward the poles.

Using measurements collected during three scientific cruises to the Agulhas Current, the Indian Ocean's version of the Gulf Stream, the researchers estimated the long-term transport of the current leveraging 22 years of satellite data. 

They found the Agulhas Current has broadened, not strengthened, since the early 1990s, due to more turbulence from increased eddying and meandering.

"Increased eddying and meandering could act to decrease poleward heat transport, while increasing coastal upwelling and the exchange of pollutants and larvae across the current from the coast to the open ocean," Elipot said.

The Agulhas, which is hundreds of kilometres long and over 2,000-metres deep, transports large amounts of ocean heat and is considered to have an influence not only on the regional climate of Africa, but on global climate as part of the ocean's global overturning circulation.

"Changes in western boundary currents could exacerbate or mitigate future climate change," lead author of the study Lisa Beal, also a professor at the Rosenstiel School noted.

"Currently, western boundary current regions are warming at three times the rate of the rest of the world ocean and our research suggests this may be related to a broadening of these current systems," Beal said