كلية الأفق الجامعية
كلية الأفق الجامعية

Knowledge Update

Scientists listen to sounds from oldest stars in our galaxy

London, June 7 (IANS) Astrophysicists from the University of Birmingham have captured the sounds of some of the oldest stars in our Milky Way galaxy, a study says.

The findings could help researchers understand how our galaxy formed and evolved.

"We were thrilled to be able to listen to some of the stellar relics of the early universe,” said lead researcher Andrea Miglio.

The researchers reported the detection of resonant acoustic oscillations of stars in 'M4', one of the oldest known clusters of stars in the galaxy, some 13 billion years old.

"The stars we have studied really are living fossils from the time of the formation of our Galaxy, and we now hope be able to unlock the secrets of how spiral galaxies, like our own, formed and evolved,” Miglio noted.

Using data from the NASA Kepler/K2 mission, the team studied the resonant oscillations of stars using a technique called asteroseismology. 

These oscillations lead to miniscule changes or pulses in brightness, and are caused by sound trapped inside the stars. By measuring the tones in this 'stellar music', it is possible to determine the mass and age of individual stars.

The findings published in the journal Monthly Notices of the Royal Astronomical Society open the door to using asteroseismology to study the very early history of our galaxy.

"Just as archaeologists can reveal the past by excavating the earth, so we can use sound inside the stars to perform Galactic archaeology,” Professor Bill Chaplin said.​

Scientists design protein to modify memory

New York, June 7 (IANS) Scientists have developed a new tool to modify brain activity and memory in targeted ways, without the help of any drugs or chemicals.

The new tool is a protein that can be encoded in animal genomes to effectively switch off their inhibitory synapses -- connections between neurons -- increasing their electrical activity.

The GFE3 protein may help researchers map the brain's connections and better understand how inhibitory synapses modulate brain function, said lead author Don Arnold, Professor at University of Southern California.

It also may enable them to control neural activity and lead to advancements in research for diseases or conditions ranging from schizophrenia to cocaine addiction, Arnold said.

"GFE3 harnesses a little known and remarkable property of proteins within the brain," Arnold said.

The protein takes advantage of an intrinsic process -- the brain's cycle of degrading and replacing proteins.

Most brain proteins last only a couple of days before they are actively degraded and replaced by new proteins. GFE3 targets proteins that hold inhibitory synapses together to this degradation system and as a result, the synapses fall apart.

"Rather than a cell deciding when a protein needs to be degraded, we sort of hijack the process," Arnold explained.

For the study, published in the journal Nature Methods, the team of scientists studied the protein's effect in both mice and zebrafish. 

The researchers found that GFE3 protein triggered the neurons on the two sides of the spine to work in opposition, generating uncoordinated movements.

Drugs could be used to inhibit inhibitory synapses in the brain, for instance benzodiazapines, which treat anxiety, insomnia or seizures. 

"Unfortunately, cells that have very different, even opposite functions tend to be right next to each other in the brain," Arnold said. 

"Thus, pharmacological experiments are especially difficult to interpret. By encoding GFE3 within the genome, we can target and modulate the inhibitory synapses of specific cells without affecting other cells that have different functions," Arnold noted.​

Scientists recover high purity metals from battery waste

London, June 6 (IANS) Finnish scientists have recovered important metals -- lithium, cobalt and nickel -- from battery waste with nearly 100 per cent purity.

Recovered metals could be used in the manufacture of batteries, and in the future especially in batteries of electric vehicles.

Researchers from Lappeenranta University of Technology (LUT) were able to extract cobalt at 99.6 per cent purity, nickel at 99.7 per cent purity, and lithium at 99.9 per cent purity from battery waste. 

"The manufacturing of new batteries requires metals of particularly high purity. If the purity of lithium is below 99.5 per cent, it is not suitable as raw material for batteries. In other words, the difference between 99.4 per cent and 99.9 per cent purity is very significant," said one of the researchers Sami Virolainen.

The findings were presented at the 'Circular Materials' conference organised by Chalmers University of Technology in Gothenburg, Sweden.

Lithium and cobalt are increasing in importance because they are needed in batteries of electronic devices and especially in electric cars. 

Forecasts indicate that the global need for lithium may quadruple between the years 2011 and 2025. 

The study separated metals through a liquid-liquid extraction process on a pilot scale. In the process, extraction takes place between two liquid phases which do not dissolve in each other. 

All other impurities are separated from the solution, leaving only lithium, cobalt and nickel. 

Previous studies have attempted to extract all three metals, but have only succeeded in extracting two at a relatively high purity and the third with low purity, the study said.

"As a separation process, liquid-liquid extraction is a viable option when nearly 100 per cent purity and a high recovery rate are required," Virolainen noted.​

Arctic getting greener due to climate change: NASA

Washington, June 6 (IANS) Using 29 years of data from satellite imageries, NASA scientists have found extensive greening in the Arctic region, thanks to rising temperatures.

The northern reaches of North America are getting greener, said the study that provides the most detailed look yet at plant life across Alaska and Canada. 

In a changing climate, almost a third of the land cover -- much of it Arctic tundra -- is looking more like landscapes found in warmer ecosystems, the researchers said.

With 87,000 images taken from Landsat satellites, the researchers found that western Alaska, Quebec and other regions became greener between 1984 and 2012. 

Landsat is a joint NASA/US Geological Survey programme that provides the longest continuous space-based record of the Earth's land vegetation in existence.

"It shows the climate impact on vegetation in the high latitudes," said one of the researchers Jeffrey Masek from NASA's Goddard Space Flight Center in Greenbelt, Maryland. 

Temperatures are warming fast in the Arctic which has led to longer seasons for plants to grow in and changes to the soils. 

Overall, the scientists found that 29.4 percent of the region greened up, especially in shrublands and sparsely vegetated areas, while 2.9 percent showed vegetation decline.

The findings were reported in the journal Remote Sensing of Environment.

Landsat, like other satellite missions, can use the amount of visible and near-infrared light reflected by the green, leafy vegetation of grasses, shrubs and trees to characterize the vegetation. 

Then, with computer programs that track each individual pixel of data over time, researchers can see if an area is greening -- if more vegetation is growing, or if individual plants are getting larger and leafier. 

If, however, the vegetation becomes sparser, the scientists would classify that area as browning.​

'Wasteful' galaxies launch heavy elements into deep space

New York, June 6 (IANS) Galaxies "waste" large quantities of heavy elements generated by star formation by ejecting them up to a million light years away into their surrounding halos and deep space, says a study.

More oxygen, carbon and iron atoms exist in the sprawling, gaseous halos outside of galaxies than exist within the galaxies themselves, leaving the galaxies deprived of raw materials needed to build stars and planets, the findings showed.

"Previously, we thought that these heavier elements would be recycled into future generations of stars and contribute to building planetary systems," said lead author of the study Benjamin Oppenheimer from University of Colorado Boulder (CU-Boulder) in the US.

"As it turns out, galaxies are not very good at recycling," Oppenheimer pointed out.

The near-invisible reservoir of gas that surrounds a galaxy, known as the circumgalactic medium (CGM), is thought to play a central role in cycling elements in and out of the galaxy, but the exact mechanisms of this relationship remain elusive. 

A typical galaxy ranges in size from 30,000 to 100,000 light years while the CGM can span up to a million light years.

The researchers used data from the Cosmic Origin Spectrograph (COS), a $70 million instrument designed at CU-Boulder and built by Colorado-based Ball Aerospace Technology Corp, to study the composition of the CGM.

The instrument is installed on NASA's Hubble Space Telescope and uses ultraviolet spectroscopy to study the evolution of the universe.

After running a series of simulations, the researchers found that the CGMs in both spiral and elliptical galaxies contained more than half of a galaxy's heavier elements, suggesting that galaxies are not as efficient at retaining their raw materials as previously thought.

The findings appeared in the journal Monthly Notices of the Royal Astronomical Society.​

Exercise can reduce chemotherapy-induced numbness

New York, June 5 (IANS) Exercise could offer a simple and inexpensive way to reduce weakness, numbness and pain in hands and feet due to chemotherapy, new research has found.

The study, involving more than 300 cancer patients, directly compared the neuropathic symptoms in non-exercisers to the pain among patients who took part in a specialized six-week walking routine with gentle, resistance-band training at home.

The exercisers reported significantly fewer symptoms of neuropathy - which includes shooting or burning pain, tingling, numbness, and sensitivity to cold - and the effects of exercise seemed to be most beneficial for older patients, said lead author Ian Kleckner, from University of Rochester Wilmot Cancer Institute in the US.

The findings are scheduled to be presented at the American Society of Clinical Oncology (ASCO) annual meeting 2016 in Chicago.

Not all chemotherapy drugs cause neuropathy, but 60 per cent of people with breast cancer and other solid tumours who receive taxanes, vinca alkaloids, and platinum-based chemotherapies will likely suffer this type of side effect, Kleckner said.

Neuropathy is more commonly associated with diabetes or nerve damage. No US Food and Drug Administration-approved drugs are available to prevent or treat chemotherapy-induced neuropathy, he added.

"Exercise is like a sledgehammer because it affects so many biological and psycho-social pathways at the same time - brain circuitry, inflammation, our social interactions - whereas drugs usually have a specific target," Kleckner said.​

Disconnect with nature raising mental illness in cities

Washington, June 5 (IANS) Mental illnesses and mood disorders are more common in urban areas partly due to reduced access to nature, say researchers.

"There's an enormous amount of disease largely tied to our removal from the natural environment," said Peter Kahn, Professor at University of Washington.

In a perspective piece published in the journal Science, the authors discussed the growing tension between an arguably necessary role urban areas play in society and the numbing, even debilitating, aspects of cities that disconnect humans from the natural world.

"Kids in large cities are growing up having never seen the stars. Can you imagine that -- having never in your life walked under the vastness of the star-lit sky, and there's that feeling of awe, restoration and imaginative spark?" Kahn said.

"As we build bigger cities, we're not aware how much and how fast we're undermining our connection to nature, and more wild nature -- the wellspring of our existence," he pointed out.

In the article, Kahn, and co-author Terry Hartig at Uppsala University in Sweden, pointed to research that shows the emotional and mental strain cities can have on people.

"I'm willing to say there's a naturalness we can achieve in cities, but not at the scale we're building or at the scale we're headed with many cities," Kahn said.

"There's nothing natural about a megacity," he noted.

There are steps cities can take to introduce nature into the urban core, including requiring buildings to have windows that open to allow in fresh air and natural light; incorporating more rooftop gardens and urban agriculture; and creating spaces within and around buildings to touch, see and smell native plants.

But these remedies first require an appreciation for nature in urban centres, as well as the space, resources and collective will to make these changes.

Kahn argues that it is more than just introducing nature into urban areas.

People must be able to interact with these elements using more of their senses in order to experience physical and psychological benefits of nature, as well as to shift the collective baseline toward better understanding and appreciation of the natural world.

For example, looking at an office plant on the windowsill might be soothing, but having a place to sit in the grass on a lunch break and perhaps even sink one's feet into the soil are sensory experiences that can deepen a person's engagement with nature.

Thoughtfully designed cities with nature can offer both the stimulation and energy of an urban area and meaningful interaction with a psychologically restorative natural environment.

"Thus, cities designed well, with nature in mind and at hand, can be understood as natural, supportive of both ecosystem integrity and public health," the authors noted.​

Brain cells hold key to decision making: Study

London, June 5 (IANS) Researchers have discovered that two neurons in the brain hold the key to explaining how complex behavioural decisions are made.

In this study, scientists monitored the snails' behaviour while they made decisions in their search for food.

"Our study reveals for the first time how just two neurons can create a mechanism in an animal's brain which drives and optimises complex decision making tasks," said lead researchers George Kemenes, Professor at the University of Sussex in Britain.

They then measured the activity in the snail's brain by using electrodes to record small electrical changes, called action potentials, in individual neurons.

The results showed a controller type neuron which lets the snail's brain know potential food is present and a second neuron which transmits signals telling the snail's brain what it's motivational state is, i.e., whether it's hungry or not.

Also, the system created by the neurons was found to enable the snails to save energy by reducing brain activity when food is not available.

"The findings can help scientists to identify other core neuronal systems which underlie similar decision making processes," Kemenes added in the paper published in the journal Nature Communications.

"The study will eventually help us design the 'brains' of robots based on the principle of using the fewest possible components necessary to perform complex tasks," Kemenes concluded.​

Now, squeeze out colours from microscopic marbles

London, June 5 (IANS) A team of researchers has devised a new method for stacking microscopic marbles into regular layers, producing intriguing materials which scatter light into intense colours and which change colour when twisted or stretched.

The team, led by the University of Cambridge, used a new method called Bend-Induced-Oscillatory-Shearing (BIOS) to produce hundreds of metres of these materials, known as 'polymer opals', on a roll-to-roll process.

The results, reported in the journal Nature Communications, has allowed such sheets to be manufactured on industrial scale, opening up applications ranging from smart clothing for people or buildings, to banknote security.

Some of the brightest colours in nature can be found in opal gemstones, butterfly wings and beetles. These materials get their colour from the systematically-ordered microstructures they contain.

When stretched, the material shifts into the blue range of the spectrum and when compressed, the colour shifts towards red. When released, the material returns to its original colour.

"Finding a way to coax objects a billionth of a metre across into perfect formation over kilometre scales is a miracle," said Professor Jeremy Baumberg, the paper's senior author.

"It is wonderful to finally understand the secrets of these attractive films," said PhD student Qibin Zhao, the paper's lead author.​

New test shows link between T-cells and ageing

New York, June 5 (IANS) Immune cells of older people are less likely to be effective at fending off the hepatitis C virus (HCV), finds a new study suggesting a correlation between ageing and the effectiveness of T-cells.

Using a novel technique called iTAST (in situ TCR affinity and sequence test), the team measured a group of donors' T-cell's affinity -- a physical parameter that determines how well the immune cell receptors recognise and bind to their antigens -- for HCV.

If a person has low-affinity T-cells for a specific virus, the body won't mount an effective fight against the virus.

However, high-affinity T-cells can launch strong fights against diseases and illnesses such as cancer and diabetes.

"T-cell affinity is a parameter that can gauge how healthy your immune system is toward a specific antigen," said lead author Jenny Jiang, Assistant Professor, at University of Texas, in the US.

The findings showed a stark difference between the HCV-specific T-cells of older and younger donors.

"The study found that as one grows older, the T-cells capable of recognising some of the viruses become progressively lower in affinity," Jiang added.

iTAST is the first technique capable of retrieving and measuring the affinity of a large volume of T-cells and their correlated receptor sequences from an individual, the researchers said in the paper published in the journal Science Translational Medicine.

"What we are doing is isolating T-cells from a patient. They are the patient's own cells, so iTAST is potentially a way to isolate safe high-affinity T-cells for adoptive immunotherapy," explained Shuqi Zhang, Graduate Student at University of Texas.

ITAST's ability to identify and retrieve a person's high-affinity T-cells could benefit immunotherapy and vaccine development, resulting in improved personalised medicine and therapies, the researchers noted.​