Knowledge Update

​New York, April 6 (IANS) Eating potassium-rich foods like sweet potatoes, avocados, spinach, beans, bananas -- and even drinking coffee -- could be key to lowering blood pressure, new research suggests.

"Decreasing sodium intake is a well-established way to lower blood pressure, but evidence suggests that increasing dietary potassium may have an equally important effect on hypertension," said Alicia McDonough, Professor at the Keck School of Medicine of the University of Southern California (USC).

Hypertension is a global health issue that affects more than one billion people worldwide. The World Health Organization (WHO) estimates that hypertension is responsible for at least 51 per cent of deaths due to stroke and 45 per cent of deaths due to heart disease.

For the study, published in the American Journal of Physiology - Endocrinology and Metabolism, McDonough looked at population, interventional and molecular mechanism studies that investigated the effects of dietary sodium and potassium on hypertension.

The review found several population studies demonstrating that higher dietary potassium (estimated from urinary excretion or dietary recall) was associated with lower blood pressure, regardless of sodium intake. 

Interventional studies with potassium supplementation also suggested that potassium provides a direct benefit.

To understand the beneficial effects of potassium on hypertension, McDonough reviewed recent studies in rodent models.

These studies indicated that the body does a balancing act that uses sodium to maintain close control of potassium levels in the blood, which is critical to normal heart, nerve and muscle function.

"When dietary potassium is high, kidneys excrete more salt and water, which increases potassium excretion," McDonough said.

When dietary potassium is low, the balancing act uses sodium retention to hold onto the limited potassium, which is like eating a higher sodium diet, she said.

But how much dietary potassium should we consume? 

A 2004 Institute of Medicine report recommends that adults consume at least 4.7 grams of potassium per day to lower blood pressure, blunt the effects of dietary sodium and reduce the risks of kidney stones and bone loss, McDonough said.

​Tokyo, April 6 (IANS) Ever wondered why babies love and adore superheroes? It may be because they are born with a sense of justice -- a concept portrayed through the heroic acts of the characters, researchers say.

The findings showed that infants, as young as six months old, who can barely talk, are capable of recognising the heroic acts of justice and thus find themselves drawn to figures who protect the weak. 

This also explains why kids and adults alike have a never-ending love affair with superhero stories in popular culture, the researchers said.

"Six-month-old infants are still in an early developmental stage and most will not yet be able to talk. Nevertheless they can already understand the power dynamics between different characters, suggesting that recognising heroism is perhaps an innate ability," said David Butler from Kyoto University in Japan.

For the study, published in the journal Nature Human Behaviour, the team conducted a series of experiments where infants were shown animations of one geometric character chasing and bumping into another, as a third character watches from a distance. 

In one version, this third party character intervenes, and in another, it escapes in another direction. 

When the infants were then shown real life replicas of these intervening and non-intervening characters, they were more likely to choose the intervener, the researchers said.

"In human society, selflessly protecting the powerless is considered an act of heroic justice," added Yasuhiro Kanakogi from the Kyoto University. 

However, understanding these may be complex as one has to first grasp the power relationship between the actors, then understand that the hero's actions are favourable for the victim but not for the villain, and finally, that the hero acted deliberately, Kanakogi said.

​London, April 5 (IANS) A common antibiotic which is used to treat a wide range of diseases, from acne to urinary tract infections, may also help treat post-traumatic stress disorder (PTSD) by suppressing fear memory, suggest results of a trial conducted in a group of health volunteers.

PTSD is a term for a broad range of psychological symptoms that can develop after someone experiences or witnesses a traumatic event. 

The disorder is caused by an overactive fear memory, and the new research, published in the journal Molecular Psychiatry, showed that a common antibiotic, doxycycline, can reduce the fear memory response in healthy volunteers.

"We have demonstrated a proof-of-principle for an entirely new treatment strategy for PTSD," said lead author Dominik Bach from the University of Zurich in Switzerland.

The theory is based on the recent discovery that our brains need proteins outside nerve cells, called matrix enzymes, to form memories. 

"Matrix enzymes are found throughout the body, and their over-activity is involved in certain immune diseases and cancers. To treat such diseases, we already have clinically approved drugs that block these enzymes, including the antibiotic doxycycline, so we wanted to see if they could help to prevent fear memories from forming in the brain," Bach, who is also affiliated to University College London, added.

"Our results support this theory, opening up an exciting avenue of research that might help us to find treatments for PTSD," Bach noted.

In the study involving 76 healthy volunteers, participants were given either doxycycline or a placebo and learnt to associate a certain colour with an electric shock. 

The screen would flash either blue or red, and one of the colours was associated with a 50 per cent chance of receiving a painful electric shock. 

A week later they were shown the colours again, accompanied by a loud sound but no shocks, and their fear responses were measured.

The fear response was 60 per cent lower in participants who had doxycycline in the first session compared to those who had the placebo, suggesting that the fear memory was significantly suppressed by the drug. 

Other cognitive measures including sensory memory and attention were not affected.

"When we talk about reducing fear memory, we are not talking about deleting the memory of what actually happened," Bach said.

"The participants may not forget that they received a shock when the screen was red, but they 'forget' to be instinctively scared when they next see a red screen," Bach said.

The findings suggest that doxycycline can disrupt the formation of negative associations in the brain.

New York, March 27 (IANS) Feeling depressed? Beat the blues by playing video games, touted as viable and effective treatment for depression, researchers said. They help in brain training. The findings showed that playing the specifically designed video game helped people feel they had some control over their depression. Such video games had the potential to target depression caused by both internal -- such as chemical imbalance or hereditary factor -- and external factors -- like issues in job or relationship. "Through the use of carefully designed persuasive message prompts ... mental health video games can be perceived and used as a more viable and less attrition-ridden treatment option," said Subuhi Khan from the University of California - Davis in the US. Portraying depression as something caused internally because of biological factors and providing a video game-based app for brain training made participants feel that they could do something to control their depression. This supports other research that shows that brain-training games have the potential to induce cognitive changes, the researchers said. On the other hand, portraying depression as a condition caused by external factors led users to spend more time playing the game -- again, perhaps giving them a feeling of control over their situation. But this result was likely due to immediate engagement and was unlikely to have long-term benefits, the study noted. In the study, forthcoming in the journal Computers in Human Behavior, the team asked 160 student volunteers to play six, three-minute games. Each game was an adaptation of neurophysiological training tasks that have been shown to improve cognitive control among people experiencing depression and ended on basic inspirational notes to inspire the participant to play the game. The results revealed that when the video game users were messaged reminders, they played the game more often and in some cases increased the time spent playing.

​Washington, March 30 (IANS) Google, the technology giant born out of the internet age, rolled out a landline telephone service on Tuesday in some US cities.

The service, known as Fiber Phone, offers basic landline features including call waiting, caller identification, unlimited local and nationwide calling and 911 services at a price of

Los Angeles, March 30 (IANS) A group of US scientists have predicted that 31 to 67 percent of Southern California beaches could be severely damaged due to rising sea levels by 2100, a new study has revealed.

The study was published online on Wednesday by the American Geophysical Union in their Journal of Geophysical Research, Xinhua news agency reported.

"Beaches are perhaps the most iconic feature of California, and the potential for losing this identity is real. The effect of California losing its beaches is not just a matter of affecting the tourism economy," Sean Vitousek, lead author of the study, said in a statement.

"Losing the protecting swath of beach sand between us and the pounding surf exposes critical infrastructure, businesses and homes to damage. Beaches are natural resources, and it is likely that human management efforts must increase in order to preserve them," said Vitousek.

Scientists applied the "CoSMoS-COAST", a newly-developed shoreline change computer modelling system for coastal hazard assessment and management planning, to simulate sandy shoreline evolution along 500 km of coastline in Southern California, which hosts complex mixtures of beach settings variably backed by dunes, cliffs, estuaries, river mouths, and urban infrastructure, providing applicability of the model to virtually any coastal setting.

"Beaches in Southern California are a crucial feature of the economy, and the first line of defence against coastal storm impacts for the 18 million residents in the region. This study indicates that we will have to perform massive and costly interventions to preserve these beaches in the future under the erosive pressures of anticipated sea level rise, or risk losing many of the economic and protective benefits beaches provide," said US Geological Survey (USGS) geologist and co-author, Patrick Barnard.

As greenhouse gas emissions continue to rise, the window to limit global warming below 2 degrees Celsius appears to be closing. Associated projections for sea-level rise generally range near or below 1 metre by 2100.

Toronto, March 30 (IANS) For at least a million years, an asteroid orbiting the "wrong" way around the Sun has been playing a cosmic game of chicken to avoid collision with Jupiter and with about 6,000 other asteroids sharing the giant planet's space, a study says.

The findings published in the journal Nature showed that the orbit has been stable for at least a million years and will be stable for at least a million years more. 

The asteroid, nicknamed Bee-Zed, is the only one in this solar system that is known both to have an opposite, retrograde orbit around the Sun while at the same time sharing a planet's orbital space, said researcher and co-author Paul Wiegert from University of Western Ontario in Canada.

Most of the known asteroids in our solar system travel around the Sun in what is called a prograde motion -- that is, counter-clockwise when visualised from above. 

But asteroid 2015 BZ509 ("Bee-Zed" for short) circles clockwise, in a retrograde motion -- moving against the flow of all other asteroids in the giant planet's orbital entourage.

Put another way, it is as if Jupiter is a monster truck on a track circling the sun, and the asteroids in Jupiter's orbit are sub-compact cars all whizzing along in the same direction. 

Bee-Zed is the rogue -- driving around the track in the wrong direction -- steering between the 6,000 other cars and swerving around the monster truck. 

And it does so every single lap, and has done so for thousands of laps for a million years or more.

So how does it avoid colliding with Jupiter? Jupiter's gravity actually deflects the asteroid's path at each pass so as to allow both to continue safely on their way, Wiegert said.

Little is known about the asteroid, which was discovered in January, 2015. It has a diametre of about three kilometres and it may have originated from the same place as Halley's comet, which also has a retrograde orbit. 

The team has not been able to determine yet if Bee-Zed is an icy comet or a rocky asteroid.

But their analysis -- based on complex calculations and on observations through the Large Binocular Camera on the Large Binocular Telescope in Mt. Graham, Arizona, during a span of 300 days -- show Bee-Zed is somehow able to maintain a stable orbit even as an outlier.

The researchers believe that learning more about the asteroid provides another intriguing glimpse into previously unknown and unmapped features of our solar system. 

"The detective work has just begun," Wiegert said.

​New York, March 29 (IANS) It is easy to try to carry on a conversation with Siri, the virtual assistant on your iPhone, or Amazon's Alexa device from your living room. But if you are doing it more lately, please beware. Researchers suggest that frequent interactions with human-like products may indicate loneliness. "If someone notices they are talking more to Siri lately, maybe that has something to do with feeling lonely," said one of the researchers Jenny Olson, Assistant Professor at the University of Kansas School of Business in the US. "From that standpoint, it's important to be aware of it," Olson said. While these humanlike products do keep people from seeking out normal human interaction, which is typically how people try to recover from loneliness, there are limits to this phenomenon, and the long-term consequences are unclear, the researchers warned in a study published online in the Journal of Consumer Research. "Generally, when people feel socially excluded, they seek out other ways of compensating, like exaggerating their number of Facebook friends or engaging in pro-social behaviour to seek out interaction with other people," Olson said. "When you introduce a human-like product, those compensatory behaviours stop," Olson noted. In four experiments, the researchers found evidence that people who felt socially excluded would exhibit those compensating behaviours unless they were given the opportunity to interact with a human-like product. "Alexa isn't a perfect replacement for your friend Alexis," lead author James Mourey of DePaul University in Chicago said. "But the virtual assistant can affect your social needs," Mourey added.

New York, March 29 (IANS) After much speculation over its built and specifications over past few months, South Korean giant Samsung on Wednesday launched its flagship device, Galaxy S8, that has a voice assistant. The device comes in two variants with different screen sizes -- the 5.8-inch Galaxy S8 and 6.2-inch Galaxy S8 Plus - and will be available from April 21. Registrations begin from March 30. The device might be priced from $720 (approximately Rs 47,000). Samsung will release these devices in India in the coming months. Samsung also revealed Bixby, a smart voice assistant to rival Apple's Siri and Google's Assistant. With a perfect amalgam of voice, vision and touch, Bixby can search restaurants, take screenshots and even book a cab for you. The technology giant has used the best hardware and provided the best features available to date in the device. The device has a bezel-less curved edge "infinity display" covered with pristine glass and a 12MP rear camera with multi-frame processing and optical image stabilisation. It has an 8MP auto-focus front shooter. The device is IP68 rated, meaning it is water and dust resistant. The company has also upped the security feature with iris scanner, face recognition and fingerprint scanner - moved to the back of the device - to unlock the device. The home button has been shifted beneath the "infinity display". Available in five different colours, the device has a Qualcomm Snapdragon 835 Octa core (2.35 GHz Quad + 1.7 GHZ Quad) processor. For models that will be available in countries other than the US, Samsung has used Exynos Octa core (2.35 GHz Quad + 1.9 GHZ Quad) processor. According to The Verge, while Galaxy S8 comes with a 3,000 mAh battery, the Galaxy S8 Plus is fitted with 3,500 mAh battery pack. The devices run on Android 7.0 Nougat and have USB-C and 3.5mm headphone jacks. The company also launched Samsung Connect app that would allow users to control a number of internet-connected home devices such as TVs or refrigerators. It also unveiled new Gear 360 camera. There's a lot riding on Samsung S8 devices due to the Galaxy Note 7 fiasco. Samsung ultimately killed that smartphone after two recalls, both related to issues with faulty batteries. Earlier this month, Samsung launched two new smartphones in 'Galaxy A' series -- 5.7-inch Galaxy A7 and 5.2-inch Galaxy A5 in India which were priced at Rs 33,490 and Rs 28,990, respectively. Samsung also joined the 'go digital' bandwagon, and last week unveiled Samsung Pay, the company's flagship mobile payments service, in India. At MWC in Barcelona this year, Samsung announced its innovative "I&G (Infill & Growth) Project" for Reliance Jio Infocomm Ltd that will help expand both the current network capacity as well as network coverage.

​New York, March 29 (IANS) Researchers have found why at around the age of four children suddenly do what three-year-olds are unable to do -- put themselves in someone else's shoes.

This enormous developmental step occurs as a critical fibre connection in the brain matures, according to a study published in the journal Nature Communications.

For the study, the research team from Max Planck Institute for Human Cognitive and Brain Sciences (MPI CBS) in Leipzig, Germany and Leiden University in the Netherlands analysed MRI data and behavioural data of 43 normally developing 3- and 4-year-old children.

"Our findings show that the emergence of mental state representation is related to the maturation of core belief processing regions and their connection to the prefrontal cortex," said the researchers.

The study showed that maturation of fibres of a brain structure called the arcuate fascicle between the ages of three and four years establishes a connection between two critical brain regions.

One region is at the back of the temporal lobe that supports adult thinking about others and their thoughts, and the other is in the frontal lobe that is involved in keeping things at different levels of abstraction and, therefore, helps us to understand what the real world is and what the thoughts of others are. 

Only when these two brain regions are connected through the arcuate fascicle can children start to understand what other people think, the study said.

Interestingly, this new connection in the brain supports this ability independently of other cognitive abilities, such as intelligence, language ability or impulse control, according to the researcher.