Knowledge Update

​Tokyo, March 27 (IANS) Highly magnetised, rapidly spinning neutron stars called magnetars can explain the energy source behind extremely unusual stellar explosions, calculations done by scientists have found.

Stellar explosions known as supernovae usually shine a billion times brighter than the Sun.

Super-luminous supernovae (SLSNe) are a relatively new and rare class of stellar explosions, 10 to 100 times brighter than normal supernovae.

But the energy source of their super-luminosity, and explosion mechanisms are a mystery and remain controversial amongst scientists.

A group of researchers led by Melina Bersten from Kavli Institute for the Physics and Mathematics of the Universe at Tokyo University tested a model that suggests that the energy to power the luminosity of two recently discovered SLSNe, SN 2011kl and ASASSN-15lh, is mainly due to the rotational energy lost by a newly born magnetar.

They analysed two recently discovered super-luminous supernovae: SN 2011kl and ASASSN-15lh.

"These supernovae can be found in very distant universe, thus possibly informing us the properties of the first stars of the universe," said Kavli IPMU principal investigator Ken'ichi Nomoto,

The team performed numerical calculations to explore the magnetar hypothesis.

It found both explosions could be understood in the framework of magnetar-powered supernovae.

"These two extreme super-luminous supernovae put to the test our knowledge of stellar explosions," added Bersten in a paper published in The Astrophysical Journal Letters in January.

To confirm the team's calculations, further observations would need to be carried out when the material ejected by the supernova is expected to become thin.

The most powerful telescopes, including the Hubble Space Telescope, will be required for this purpose.

If correct, these observations will allow scientists to probe the inner part of an exploding object and provide new insight on its origin and evolution of stars in the Universe.​

​New York, March 27 (IANS) Stop acting like a tough man and start facing the reality. A team of US researchers has found that most men on an average die five years earlier than women as they are less likely than women to go to a doctor.

The study also says, if they do go, they are more likely to choose a male doctor and are less likely to be honest with that doctor about their symptoms.

The researchers found that men who held traditional beliefs about masculinity -- that men should be tough, brave, self-reliant and restrained in their expression of emotion -- were more likely to ignore medical problems, or at least put off dealing with them, than women or than men with less traditional beliefs.

"The question that we wanted to answer was, why do men die earlier than women?" said Diana Sanchez from Rutgers University in the US.

"Men can expect to die five years earlier than women and physiological differences don't explain that difference," Sanchez added in the paper published in the journal Preventive Medicine.

For their study, researchers asked about 250 men participants to fill an online questionnaire designed to elicit their opinions about manhood and relative attributes of men and women.

They also answered questions about the preference of doctor.

The higher they scored on the masculinity scale, the more likely participants were to prefer a male to a female doctor.

They were more likely to choose a male doctor, based on the belief that male doctors were more competent than female doctors.

"That's because they don't want to show weakness or dependence to another man, including a male doctor," Sanchez explained.

The researchers then recruited 250 male undergraduates at a large public university and had them fill out similar questionnaires.

Each subject was interviewed by male and female pre-medical and nursing students about their medical conditions.

Ironically, the researchers found that men tend to be more honest about their medical symptoms with female doctors, because to be honest about vulnerabilities causes them no loss of status with women.​

​New York, March 28 (IANS) Higher rates of breastfeeding, use of vaccinations and lower rates of smoking by mothers have reduced the rates of ear infections during the first year of a baby, finds a new study.

"Prolonged breastfeeding was associated with significant reductions in both colds and ear infections, which is a common complication of the cold," said lead researcher Tasnee Chonmaitree, professor at University of Texas in US.

"It is likely that medical interventions in the past few decades, such as the use of pneumonia and flu vaccines and decreased smoking helped reduce ear infection incidences," he said.

Ear infections in young infants who are under six months old are at an increased risk of having the infection recurrently later in life. 

The findings, published in the journal Pediatrics, revealed that the rates of ear infection dropped from 18 to 6 percent in three month olds, from 39 to 23 percent in six month olds and from 62 to 46 percent in one year olds.

For the study, 367 babies less than one month old were investigated from October 2008 to March 2014, till their first birthday.

The team collected nose and throat mucus samples throughout the study to seek out and identify infections and gathered information on family history of ear infections, cigarette smoke exposure and breast versus formula feeding. 

Parents notified whenever their baby showed any signs of an ear infection or upper respiratory infection, which is the common cold. 

"We clearly showed that frequent upper respiratory infections, carriage of bacteria in the nose, and lack of breastfeeding are major risk factors for ear infections," said Chonmaitree. 

Acute otitis media, or an ear infection, is one of the most common childhood infections, the leading cause of visits to doctors by children and the most common reason children take antibiotics or undergo surgery.

Dubai, March 28 (IANS/WAM) The official logo of Dubai Expo 2020 was unveiled by vice president and prime minister of the UAE, Ruler of Dubai Sheikh Mohammed bin Rashid Al Maktoum.

The new logo is inspired by a 4,000 year-old piece of jewellery found at "Saroug Al Hadeed", an ancient archaeological site discovered by Mohammed bin Rashid in 2002.

Mohammed bin Rashid on Sunday said: "We have chosen an authentic Emirati logo for Dubai Expo 2020. The design of the logo is inspired by a civilisation that existed 4,000 years ago in an area extending from Baynounah in Abu Dhabi to Saroug Al Hadeed in Dubai and from Maliha Valley in Sharjah to the mountains of Ras al Khaimah and Fujairah."

He also said: "Dubai is the city of gold, but the minds and hands of our citizens are more precious than gold."

The Saroug Al Hadeed archaeological site is one of the most important sites discovered in Arabian Peninsula and one of the main centres for the manufacture of copper tools in the region since the beginning of the Iron Age.

The site contains large quantities of metal ores. Thousands of rare artefacts have been discovered in the site, including swords and daggers.

​New York, March 28 (IANS) Researchers have identified a single, universal facial expression that is interpreted across cultures -- whether one speaks Mandarin Chinese or English -- as the embodiment of negative emotion.

This facial expression that the researchers call “Not face” consists of furrowed brows of "anger", raised chin of "disgust" and the pressed-together lips of "contempt", the study said.

"To our knowledge, this is the first evidence that the facial expressions we use to communicate negative moral judgment have been compounded into a unique, universal part of language," said Aleix Martinez, cognitive scientist and professor of electrical and computer engineering at the Ohio State University in the US.

The look proved identical for native speakers of English, Spanish, Mandarin Chinese and American Sign Language (ASL), the researchers said.

The study, published in the journal Cognition, also revealed that our facial muscles contract to form the "not face" at the same frequency at which we speak.

For this new study, the researchers hypothesised that if a universal "not face" existed, it was likely to be combination of three basic facial expressions that are universally accepted to indicate moral disagreement -- anger, disgust and contempt.

To test the hypothesis, they recruited 158 Ohio State students in front of a digital camera. The students, divided in four groups, were filmed and photographed as they had a casual conversation with the person behind the camera in their native language.

In all four groups -- speakers of English, Spanish, Mandarin and ASL -- the researchers identified clear grammatical markers of negation. 

The students' answers translated to statements like "That's not a good idea," and "They should not do that."

The researchers manually tagged images of the students speaking, frame by frame, to show which facial muscles were moving and in which directions. 

Then computer algorithms searched the thousands of resulting frames to find commonalities among them.

Regardless of language, the participants' faces displayed the “Not Face” when they communicated negative sentences.​

​New York, March 28 (IANS) Scientists have developed a new way to make "polymer nanobrush" -- bristly materials which prevent dust from accumulating on various surfaces.

Polymer brushes have been used to coat everything from eyeglass lenses, boats and medical devices -- where they keep away smudges, damaging chemicals and germs -- to artificial joints and mechanical components in vehicles where they act as a lubricant.

Developed by a team of engineers led by Christopher Li, professor at Drexel University's college of engineering in Philadelphia, it gives scientists a higher degree of control over the shape of the brush and bristles and is much more efficient.

"The past few decades witnessed exciting progresses in studies on polymer brushes, and they show great promises in various fields, including coating, biomedical, sensing, catalysis to name just a few," Li said. 

His approach involves growing a functional two-dimensional sheet of polymer crystals -- similar to a nanoscale piece of double-sided tape. When the sheet is stuck to an existing substrate, and the crystals are dissolved, the remaining polymer chains spring up, forming the bristles of the brush.

"We believe that our discovery of a new way to make polymer brushes is a significant advance in the field and will enable use of the brushes in exciting new ways," added Li in the study published in the journal Nature Communications.

The new brush is the most densely packed polymer brushes to date, with bristles less than a nanometre apart.

Polymer brush materials are especially useful in situations where pieces need to fit tightly together but need to be able to move without friction throwing a wrench in the works. 

These are also effective for keeping important surfaces free of particles, chemicals, proteins and other fouling agents. ​

​New York, March 27 (IANS) Researchers have developed a way to make a magnetic material that could lead to lighter and smaller, cheaper and better-performing high-frequency transformers, needed for more flexible energy storage systems and widespread adoption of renewable energy.

Transportable energy storage and power conversion systems, which can fit inside a single semi-trailer, could make it cost effective to rapidly install solar, wind and geothermal energy systems in even the most remote locations.

"Such modular systems could be deployed quickly to multiple sites with much less assembly and validation time," said one of the researchers Todd Monson from Sandia National Laboratories in the US.

The new manufacturing method enables the creation of transformer cores from raw starting materials in minutes, without decomposing the required iron nitrides, as could happen at the higher temperatures used in conventional method, the researchers said.

Using this method could make transformers up to 10 times smaller than they are currently, Monson said in a statement.

Due to its magnetic properties, iron nitride transformers can be made much more compact and lighter than traditional transformers, with better power-handling capability and greater efficiency.

They will require only air cooling, another important space saver. Iron nitride also could serve as a more robust, high-performance transformer core material for the electrical grid.

So far, Monson and his colleagues have demonstrated the fabrication of iron nitride transformer cores with good physical and magnetic characteristics and now are refining their process and preparing to test the transformers in power-conversion test beds.​

​Beijing, March 27 (IANS) China will change the tax rules on online retail goods from April 8 to level the playing field for e-commerce platforms and traditional retailers and importers, a media report said on Sunday.

​London, March 26 (IANS) Exploring new pose for selfies? Thighbrows and duckface poses are things of the past. The new Tyrannosaurus rex (T.rex) hands pose is the latest trend, the media reported on Thursday.

​London, March 27 (IANS) Just one session of a non-invasive brain stimulation technique can reduce core symptoms of anorexia nervosa, including the urge to restrict food intake and feeling fat, says a study.

The researchers assessed whether repetitive transcranial stimulation (rTMS), already an approved treatment for depression, is also effective in reducing symptoms of anorexia.

Up to 20 percent of people with anorexia die prematurely from the disorder and treatments in adults are moderately effective, with only 20-30 per cent of people recovering from the best

"With rTMS we targeted the dorsolateral prefrontal cortex, an area of the brain thought to be involved in some of the self-regulation difficulties associated with anorexia. This technique alters neural activity by delivering magnetic pulses to specific regions of the brain, which feels like a gentle tapping sensation on the side of the head," said first author of the study Jessica McClelland from King's College London.

"We found that one session of rTMS reduced the urge to restrict food intake, levels of feeling full and levels of feeling fat, as well as encouraging more prudent decision-making. Taken together, these findings suggest that brain stimulation may reduce symptoms of anorexia by improving cognitive control over compulsive features of the disorder," McClelland noted.

The findings were published in the journal PLOS ONE.

In the study, 49 people completed food exposure and decision-making tasks, both before and after a session of either real or placebo rTMS. Symptoms of anorexia were measured immediately prior to and following rTMS, as well as 20 minutes and 24 hours after the session.

Compared to the placebo group, they found that participants who had real rTMS showed a tendency for more prudent decision-making.​