Knowledge Update

​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.​

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.​

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.​

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.​

​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 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.​

London, June 6 (IANS) There could soon be a pill to reduce your calorie consumption as researchers have identified a bitter plant extract that can suppress food intake by stimulating the secretion of gut peptide hormones involved in appetite regulation.

Gut chemosensory mechanisms, particularly those involved in detecting and relaying to the brain the chemical composition of food during digestion, play an important role in regulating appetite and food intake. 

The researchers hypothesised that activation of specific bitter taste receptors which are expressed throughout the gastrointestinal tract by hormone secreting 'enteroendocrine' cells, could also regulate food intake by triggering the release of satiety or 'fullness' hormones, a mechanism termed by the team as the "bitter brake."

The study was conducted by John Ingram and colleagues from the New Zealand Institute for Plant & Food Research Limited and University of Auckland, New Zealand.

The team screened over 900 plant extracts for their ability to stimulate enteroendocrine "I cell" hormone release before identifying a highly bitter, non-nutritive plant derived ingredient they have called "Amarasate extract" to take forward into clinical testing. 

Twenty lean healthy male volunteers were recruited (mean body mass index 23.4 kg/m2) with 19 completing all three treatments within the randomised, double-blind study.

Treatments comprising 500 mg Amarasate extract or a placebo were administered for targeted intestinal (duodenal) or stomach (gastric) release. 

The researchers found that, compared with placebo, both gastric and duodenal delivery of the Amarasate extract stimulated significant increases in the gut peptide hormones CCK, GLP-1 and PYY while significantly reducing total (lunch plus snack) meal energy intake by 218 calories and 226 calories, respectively. 

However, no significant treatment effects were observed for any subjective ratings of appetite or nausea.

"We have demonstrated that activation of the 'bitter brake' mechanism by a bitter plant extract can stimulate the release of gut peptide hormones involved in appetite regulation and suppress subsequent feeding behaviour in healthy men," the authors noted.

The findings were presented at the 2016 European Obesity Summit in Gothenburg, Sweden.​

​Washington, June 3 (IANS) In a discovery that points to exciting geological activity on a distant cold planet billions of miles from the Earth, NASA scientists have discovered that the icy surface of Pluto's "heart" is being constantly renewed by a process called convection that replaces older surface ice with fresher material.

The prime attraction in the photos of Pluto sent by NASA’s New Horizon spacecraft during its July 2015 flyby was its heart -- a large plain informally known as Sputnik Planum.

Combining computer models with topographic and compositional data gathered by the mission last summer, the scientists showed that the surface of Sputnik Planum is covered with icy, churning, convective "cells" 16 to 48 kms across, and less than one million years old. 

The findings offer additional insight into the unusual and highly active geology on Pluto and, perhaps, other bodies like it on the outskirts of the solar system.

"For the first time, we can really determine what these strange welts of the icy surface of Pluto really are," said lead researcher William McKinnon from Washington University in St. Louis. 

"We found evidence that even on a distant cold planet billions of miles from Earth, there is sufficient energy for vigorous geological activity, as long as you have 'the right stuff,' meaning something as soft and pliable as solid nitrogen," noted McKinnon, who is co-investigator on the New Horizons science team.

The study was published in the journal Nature.

McKinnon and colleagues believe the pattern of these cells stems from the slow thermal convection of the nitrogen-dominated ices that fill Sputnik Planum. 

A reservoir that is likely several miles deep in some places, the solid nitrogen is warmed by Pluto's modest internal heat, becomes buoyant and rises up in great blobs -- like a lava lamp -- before cooling off and sinking again to renew the cycle. 

The computer models showed that ice need only be a few miles deep for this process to occur, and that the convection cells are very broad. 

These convective surface motions average only a few centimetres a year - about as fast as your fingernails grow - which means cells recycle their surfaces every 500,000 years or so. While slow on human clocks, it is a fast clip on geological timescales, the researchers said.

"This activity probably helps support Pluto's atmosphere by continually refreshing the surface of 'the heart,'" McKinnon said. 

"It wouldn't surprise us to see this process on other dwarf planets in the Kuiper Belt," he added.

New Horizons flew through the Pluto system on July 14, 2015, making the first close observations of Pluto and its family of five moons.​

Toronto, June 4 (IANS) A dietary supplement containing a blend of 30 vitamins and minerals has the potential to slow the progress of catastrophic neurological diseases such as Alzheimer's and Parkinson's, researchers say.

The supplement has shown remarkable anti-ageing properties that can prevent and even reverse massive brain cell loss, according to the study by Ontario's McMaster University researchers.

"The findings are dramatic," said lead author of the study Jennifer Lemon.

"Our hope is that this supplement could offset some very serious illnesses and ultimately improve quality of life," Lemon noted.

The formula contains common ingredients such as vitamins B, C and D, folic acid, green tea extract, cod liver oil and other nutraceuticals.

The mice used in this study had widespread loss of more than half of their brain cells, severely impacting multiple regions of the brain by one year of age, the human equivalent of severe Alzheimer's disease.

The mice were fed the supplement on small pieces of bagel each day over the course of several months. Over time, researchers found that it completely eliminated the severe brain cell loss and abolished cognitive decline.

"The research suggests that there is tremendous potential with this supplement to help people who are suffering from some catastrophic neurological diseases," Lemon noted.

The findings were published online in the journal Environmental and Molecular Mutagenesis.

"We know this because mice experience the same basic cell mechanisms that contribute to neurodegeneration that humans do. All species, in fact. There is a commonality among us all," she explained.

In addition to looking at the major markers of aging, they also discovered that the mice on the supplements experienced enhancement in vision and most remarkably in the sense of smell - the loss of which is often associated with neurological disease - improved balance and motor activity.

The next step in the research is to test the supplement on humans, likely within the next two years, and target those who are dealing with neurodegenerative diseases, the researchers said.​

​London, June 4 (IANS) What archaeologists earlier thought to be ancient underwater remains of a long lost Greek city were in fact created by a naturally occurring phenomenon, suggests new research.

When underwater divers discovered what looked like paved floors, courtyards and colonnades, they thought they had found the ruins of a long-forgotten civilisation that perished when tidal waves hit the shores of the Greek holiday island Zakynthos.

But new research published in the journal Marine and Petroleum Geology reveals that the site discovered a few years ago was created by a natural geological phenomenon that took place in the Pliocene era - up to five million years ago.

"The site was discovered by snorkelers and first thought to be an ancient city port, lost to the sea. There were what superficially looked like circular column bases, and paved floors. But mysteriously no other signs of life - such as pottery," said lead author Julian Andrews , professor at the University of East Anglia in Norwich, England.

The research team went on to investigate in detail the mineral content and texture of the underwater formation in minute detail, using microscopy, X-ray and stable isotope techniques.

"We investigated the site, which is between two and five meters under water, and found that it is actually a natural geologically occurring phenomenon,” Andrews said.

"The disk and doughnut morphology, which looked a bit like circular column bases, is typical of mineralisation at hydrocarbon seeps - seen both in modern seafloor and palaeo settings,” Andrews noted.

Microbes in the sediment use the carbon in methane as fuel. Microbe-driven oxidation of the methane then changes the chemistry of the sediment forming a kind of natural cement, known to geologists as concretion.

"In this case the cement was an unusual mineral called dolomite which rarely forms in seawater, but can be quite common in microbe-rich sediments,” Andrews explained.​