Knowledge Update

​London, Feb 23 (IANS) People who suffer long-term stress may also be more prone to gaining extra kilos overtime, says a study. The findings, published in the journal Obesity, are based on examination of hair samples for levels of cortisol, a hormone which regulates the body's response to stress. The study showed that exposure to higher levels of cortisol over several months is associated with people being more heavily, and more persistently, overweight. "People who had higher hair cortisol levels also tended to have larger waist measurements, which is important because carrying excess fat around the abdomen is a risk factor for heart disease, diabetes, and premature death," said lead researcher Sarah Jackson from the University College London. "These results provide consistent evidence that chronic stress is associated with higher levels of obesity," Jackson added. Chronic stress has long been hypothesised to be implicated in obesity -- people tend to report overeating and 'comfort eating' foods high in fat, sugar and calories in times of stress, and the stress hormone cortisol plays an important role in metabolism and determining where fat is stored. Previous studies looking at the link between cortisol and obesity relied mainly on measurements of the hormone in blood, saliva or urine which may vary according to the time of day and other situational factors. These studies failed to capture long-term cortisol levels. This research involved 2,527 men and women aged 54 and older taking part in the English Longitudinal Study of Ageing, taking data over a four-year period. In the research, the scientists took a lock of hair two centimetre long from each participant which was cut as close possible to a person's scalp. This represented approximately two months' hair growth with associated accumulated levels of cortisol. The researchers found that people who had higher levels of cortisol present in their hair tended to have larger waist circumference measurements, were heavier, and had a higher body mass index (BMI).

​Washington, Feb 23 (IANS) In a remarkable step towards answering the question "Are we alone in the universe", astronomers have spotted a nearby star with seven Earth-size planets which could harbour liquid water, key to life as we know it, NASA said.

At about 40 light-years (235 trillion miles) from Earth, the system of planets is relatively close to us, in the constellation Aquarius. 

All of these seven planets could have liquid water under the right atmospheric conditions, but the chances are highest with three of the plants which are located in the habitable zone, according to the researchers.

"This discovery could be a significant piece in the puzzle of finding habitable environments, places that are conducive to life," said Thomas Zurbuchen, Associate Administrator of NASA's Science Mission Directorate in Washington. 

Because they are located outside of our solar system, these planets are scientifically known as exoplanets.

This exoplanet system is called TRAPPIST-1, named for The Transiting Planets and Planetesimals Small Telescope (TRAPPIST) in Chile. 

"The seven wonders of TRAPPIST-1 are the first Earth-size planets that have been found orbiting this kind of star," said Michael Gillon, lead author of the paper and the principal investigator of the TRAPPIST exoplanet survey at the University of Liege, Belgium. 

"It is also the best target yet for studying the atmospheres of potentially habitable, Earth-size worlds," Gillon said.

In May 2016, researchers using TRAPPIST announced they had discovered three planets in the system. 

Assisted by several ground-based telescopes, including the European Southern Observatory's Very Large Telescope, NASA's Spitzer space telescope confirmed the existence of two of these planets and discovered five additional ones, increasing the number of known planets in the system to seven.

Using Spitzer data, the team precisely measured the sizes of the seven planets and developed first estimates of the masses of six of them, allowing their density to be estimated.

Based on their densities, all of the TRAPPIST-1 planets are likely to be rocky, according to the new results published on Wednesday in the journal Nature

Further observations will not only help determine whether they are rich in water, but also possibly reveal whether any could have liquid water on their surface. 

The mass of the seventh and farthest exoplanet has not yet been estimated. But scientists believe it could be an icy, "snowball-like" world, but further observations are needed.

The discovery of the seven exoplanets sets a new record for greatest number of habitable-zone planets found around a single star outside our solar system. 

In contrast to our sun, the TRAPPIST-1 star -- classified as an ultra-cool dwarf -- is so cool that liquid water could survive on planets orbiting very close to it, closer than is possible on planets in our solar system. 

All seven of the TRAPPIST-1 planetary orbits are closer to their host star than Mercury is to our sun.

The planets also are very close to each other. If a person was standing on one of the planet's surface, they could gaze up and potentially see geological features or clouds of neighbouring worlds, which would sometimes appear larger than the moon in the Earth's sky, NASA said.

London, Feb 23 (IANS) Would you like to know what does the future hold for you? If yes, you may have only a few company. A new study shows that given the chance to see into the future, most people would rather not know what life has in store for them -- whether it brings good things or bad.

"In Greek mythology, Cassandra, daughter of the King of Troy, had the power to foresee the future. But, she was also cursed and no one believed her prophecies," said the study's lead author Gerd Gigerenzer from Max Planck Institute for Human Development in in Berlin, Germany. 

"In our study, we've found that people would rather decline the powers that made Cassandra famous, in an effort to forgo the suffering that knowing the future may cause, avoid regret and also maintain the enjoyment of suspense that pleasurable events provide," Gigerenzer said.

The findings, published in the journal Psychological Review, are based on two studies involving more than 2,000 adults in Germany and Spain.

The study found that 85 to 90 per cent of people would not want to know about upcoming negative events, and 40 to 70 percent preferred to remain ignorant of upcoming positive events. 

Only one percent of participants consistently wanted to know what the future held. 

The researchers also found that people who prefer not to know the future are more risk averse and more frequently buy life and legal insurance than those who want to know the future. 

This suggests that those who choose to be ignorant anticipate regret, Gigerenzer said. 

The length of time until an event would occur also played a role. Deliberate ignorance was more likely the nearer the event. 

For example, older adults were less likely than younger adults to want to know when they or their partner would die, and the cause of death. 

"Not wanting to know appears counter-intuitive and may raise eyebrows, but deliberate ignorance, as we've shown here, doesn't just exist; it is a widespread state of mind," Gigerenzer said.

​London, Feb 23 (IANS) Injecting a particular weight loss drug in combination with diet and exercise may reduce risk of diabetes by 80 per cent in individuals with obesity and prediabetes, a study said.

The results of the international clinical trial showed that liraglutide promoted weight loss by interacting with the areas of the brain that control appetite and energy intake.

Published in the journal The Lancet, the results showed that three years of continuous treatment with once-daily liraglutide 3.0 mg, in combination with diet and increased physical activity, reduced the risk of developing the Type 2 diabetes.

In fact, in 60 per cent of those patients with borderline diabetes the condition was reversed, and patients returned to healthy blood sugar levels, the study showed.

"Liraglutide promotes weight loss by activating brain areas that control appetite and eating, so that people feel fuller sooner after meals and their food intake is reduced," said Carel le Roux, Professor at Imperial College London. 

"Although liraglutide's role in weight loss is well known, this is the first time it has been shown to essentially reverse prediabetes and prevent diabetes, albeit with the help of diet and exercise," le Roux added.

Of the patients who did go on to develop diabetes, those who were given liraglutide, took nearly three times longer to develop the disease. 

In addition, liraglutide also helped patients lose seven per cent body weight compared to only two per cent in the placebo group, the researchers said.

"Liraglutide 3.0 mg can provide us with a new therapeutic approach for patients with obesity and prediabetes," explained John Wilding, Professor at the University of Liverpool.

For this obesity and prediabetes trial, the team followed 2,254 adults with prediabetes at 191 research sites in 27 countries worldwide. 

The participants were randomly allocated either liraglutide 3.0 mg or a placebo delivered by injection under the skin once daily for 160 weeks. 

They were also placed on a reduced calorie diet and advised to increase their physical activity.

​Washington, Feb 23 (IANS) In a major boost to the search for alien life outside our solar system, astronomers have spotted the first known system of seven Earth-size planets around a single star, NASA said.

All of these seven planets could have liquid water -- key to life as we know it -- under the right atmospheric conditions, but the chances are highest with three of the plants which are located in the habitable zone, according to the researchers.

"This discovery could be a significant piece in the puzzle of finding habitable environments, places that are conducive to life," said Thomas Zurbuchen, Associate Administrator of NASA's Science Mission Directorate in Washington. 

At about 40 light-years (235 trillion miles) from Earth, the system of planets is relatively close to us, in the constellation Aquarius. 

Because they are located outside of our solar system, these planets are scientifically known as exoplanets.

This exoplanet system is called TRAPPIST-1, named for The Transiting Planets and Planetesimals Small Telescope (TRAPPIST) in Chile. 

In May 2016, researchers using TRAPPIST announced they had discovered three planets in the system. 

Assisted by several ground-based telescopes, including the European Southern Observatory's Very Large Telescope, NASA's Spitzer space telescope confirmed the existence of two of these planets and discovered five additional ones, increasing the number of known planets in the system to seven.

Using Spitzer data, the team precisely measured the sizes of the seven planets and developed first estimates of the masses of six of them, allowing their density to be estimated.

Based on their densities, all of the TRAPPIST-1 planets are likely to be rocky, according to the new results published on Wednesday in the journal Nature

Further observations will not only help determine whether they are rich in water, but also possibly reveal whether any could have liquid water on their surfaces. 

The mass of the seventh and farthest exoplanet has not yet been estimated. But scientists believe it could be an icy, "snowball-like" world, but further observations are needed.

The discovery of the seven exoplanets sets a new record for greatest number of habitable-zone planets found around a single star outside our solar system. 

"The seven wonders of TRAPPIST-1 are the first Earth-size planets that have been found orbiting this kind of star," said Michael Gillon, lead author of the paper and the principal investigator of the TRAPPIST exoplanet survey at the University of Liege, Belgium. 

"It is also the best target yet for studying the atmospheres of potentially habitable, Earth-size worlds," Gillon said.

In contrast to our sun, the TRAPPIST-1 star - classified as an ultra-cool dwarf - is so cool that liquid water could survive on planets orbiting very close to it, closer than is possible on planets in our solar system. 

All seven of the TRAPPIST-1 planetary orbits are closer to their host star than Mercury is to our sun, the researchers said.

​Canberra, Feb 23 (IANS) Australian engineers have created an advanced microscope using a beefed-up "barcode scanner", which they believe will help doctors better analyse complex medical conditions such as cancer.

Engineers from the Australian National University (ANU) said the microscope can film moving blood cells and neurons in living animals, something which they say will help doctors and scientists to research complex blood disorders, Xinhua news agency reported.

Steve Lee, a biomedical optics engineer at the ANU, said the microscope used technology similar to retail barcode scanners and office laser printers.

"Scientists can use our new microscope to analyse complex medical problems ranging from blood disorders and cancer to neurological disorders," Lee said in a statement released on Thursday.

"The microscope can speed up or slow down to capture the slow moving cells in a blood stream or live neurons firing rapidly in the brain, making it much more flexible than other microscopes on the market."

In traditional, "supermarket-style", barcode scanners, a laser beam bounces off a spinning polygon mirror, allowing it to scan across a sample very quickly. The scanner detects the unique sequence of each barcode to identify each certain product.

Lee said the ANU microscope used a more powerful laser beam as the light source and up to 36 mirror facets to "scan the laser beam across the biological sample in a few thousandths of a second".

"We achieve the same imaging resolution of conventional scanning microscopes on the market but at double the speed," he said.

"The innovation here is that we modernised the polygon mirror microscopy system with advanced electronics and software controls to enable real-time imaging applications, with up to 800 frames per second."

Washington, Feb 22 (IANS) NASA's Fermi gamma-ray space telescope has found a signal at the centre of the neighbouring Andromeda galaxy that could be coming from dark matter, an unknown substance that makes up most of the universe, according to a study.

The gamma-ray signal is similar to one seen by Fermi at the centre of our own Milky Way galaxy.

"Our galaxy is so similar to Andromeda, it really helps us to be able to study it, because we can learn more about our galaxy and its formation," said study co-author Regina Caputo, a research scientist at NASA's Goddard Space Flight Centre in Greenbelt, Maryland. 

Gamma rays are the highest-energy form of light, produced by the universe's most energetic phenomena.

They are common in galaxies like the Milky Way because cosmic rays, particles moving near the speed of light, produce gamma rays when they interact with interstellar gas clouds and starlight.

Surprisingly, the latest Fermi data shows the gamma rays in Andromeda -- also known as M31 -- are confined to the galaxy's centre instead of spread throughout, said the study to be published in an upcoming issue of The Astrophysical Journal.

To explain this unusual distribution, scientists are proposing the emission may come from several undetermined sources. One of them could be dark matter.

"We expect dark matter to accumulate in the innermost regions of the Milky Way and other galaxies, which is why finding such a compact signal is very exciting," said led scientist Pierrick Martin, an astrophysicist at the National Center for Scientific Research and the Research Institute in Astrophysics and Planetology in Toulouse, France. 

"M31 will be a key to understanding what this means for both Andromeda and the Milky Way," Martin said.

Another possible source for this emission, according to the scientists, could be a rich concentration of pulsars in M31's centre.

​New York, Feb 21 (IANS) The much-anticipated video recording 'Spectacles' from photo-sharing service Snapchat is now available online for users in the US at $129.99. Snapchat 'Spectacles' record video and pair to user's phone over Bluetooth or WiFi which can then be uploaded to the user's Snapchat account. According to a report in Fortune, 'Spectacles' come with a charging case and cable in three shades including black, coral red and teal blue. "Snap's (Snapchat's parent company) IPO is expected to take place on March 2, so the move to sell Spectacles to the masses could give Snap a stronger footing as it tries to court investors during its whirlwind roadshow over the next two weeks," the report said. 'Spectacles' was launched in September last year and was available for purchase from vending machines at surprise locations in the US. The five-year-old Snap Inc, which filed documents for one of the biggest IPO by a technology company, is valued at $20-$25 billion.

​Spain, Feb 21 (IANS) Chinese smartphone maker Oppo will unveil a new smartphone with 5x zooming ability at the Mobile World Congress (MWC) in Barcelona, Spain, later this month. The company has teased the smartphone with the tagline 'Go 5x further' on its Facebook page. "We chose MWC to unveil the 5x technology with the belief that we can inspire the industry to aim higher, and continue to create pioneering products that give amazing experiences to consumers," GSMArena.com quoted Sky Li, Vice President, Oppo and Managing Director, International Mobile Business & President, Oppo India, as saying. According to a recent report from market analytics firm Counterpoint Research, "Oppo, Huawei, Vivo, Meizu and Gionee captured a combined 58 per cent of the total Chinese smartphone market in 2016."

Sydney, Feb 21 (IANS) Australia's New South Wales state will focus on better preparing students for university and employment in a major overhaul of its school curriculum.

New South Wales on Tuesday unveiled changes to its high school syllabus for the first time in 18 years, the BBC reported.

The new focus eschews "social context" teaching -- which had drawn criticism -- for more in-depth, critical thinking.

It comes after an international study in December showed Australia's maths and science ranking had tumbled.

The changes address recent criticism over a lack of rigour, said Tom Alegounarias, the head of the state's Education Standards Authority.

"We reviewed the whole (syllabus), we looked at what the community is demanding for now and in the future," Alegounarias told the Australian Broadcasting Corporation.

"The major shift is towards greater depth, rigour, and mastery of content learning."

However, education officials said the concerns were addressed.

Maths will now include more statistics and algorithms, such as those used by internet search engines.

In English, texts will no longer be studied through themes like "journey" or "discovery" but examined for their individual merit.

In history, subjects such as the Enlightenment and the Industrial Revolution will be explored in depth, rather than focusing on a breadth of topics.

The new curriculum will be introduced from next year, the BBC added.