Knowledge Update

​New York, May 24 (IANS) Higher long-term fluctuations in blood pressure readings may be linked to faster declines in brain and cognitive function among older adults, says a study.

"Blood pressure variability might signal blood flow instability, which could lead to the damage of the finer vessels of the body with changes in brain structure and function," said Bo (Bonnie) Qin, lead study author and a postdoctoral scholar at Rutgers Cancer Institute in New Brunswick, New Jersey, US.

"These blood pressure fluctuations may indicate pathological processes such as inflammation and impaired function in the blood vessels themselves," she noted.

For the study, the researchers analysed results from 976 Chinese adults (half women, age 55 and or older) who participated in the China Health and Nutrition Survey over a period of five years. 

Blood pressure variability was calculated from three or four visits to the health professional. Participants also underwent a series of cognitive quizzes such as performing word recall and counting backwards.

Higher visit-to-visit variability in the top number in a blood pressure reading (systolic blood pressure) was associated with a faster decline of cognitive function and verbal memory, the findings showed.

However, higher variability in the bottom number (diastolic blood pressure) was associated with faster decline of cognitive function among adults aged 55 to 64, but not among those aged 65 and older.

The findings appeared in the journal Hypertension: Journal of the American Heart Association.

While physicians tend to focus on average blood pressure readings, the new findings suggest that high variability may be something for physicians to watch for in their patients.

"Controlling blood pressure instability could possibly be a potential strategy in preserving cognitive function among older adults," Qin said.​

Munich, May 23 (IANS) Bayer, Germany-based life science company in health and agriculture has offered to buy Monsanto, the American seed multinational in an all-cash deal worth $62 billion.

Washington, May 24 (IANS) Solar storms four billion years ago may have provided the crucial energy needed to warm Earth and seed life despite the Sun's faintness, new research has revealed.

Some four billion years ago, the sun shone with only about three-quarters the brightness we see today, but its surface roiled with giant eruptions spewing enormous amounts of solar material and radiation out into space. 

The eruptions also may have furnished the energy needed to turn simple molecules into the complex molecules such as RNA and DNA that were necessary for life, said NASA researchers.

“Back then, Earth received only about 70 percent of the energy from the Sun than it does today,” said Vladimir Airapetian, solar scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

That means Earth should have been an icy ball.

“Instead, geological evidence says it was a warm globe with liquid water. We call this the 'Faint Young Sun Paradox'. Our new research shows that solar storms could have been central to warming Earth,” he added.

Understanding what conditions were necessary for life on our planet helps us both trace the origins of life on Earth and guide the search for life on other planets.

Until now, however, fully mapping Earth's evolution has been hindered by the simple fact that the young Sun wasn't luminous enough to warm Earth.

Scientists are able to piece together the history of the sun by searching for similar stars in our galaxy.

By placing these sun-like stars in order according to their age, the stars appear as a functional timeline of how our own Sun evolved.

It is from this kind of data that scientists know the sun was fainter four billion years ago.

Such studies also show that young stars frequently produce powerful flares - giant bursts of light and radiation -- similar to the flares we see on our own Sun today.

Such flares are often accompanied by huge clouds of solar material, called coronal mass ejections or CMEs which erupt out into space.

NASA's Kepler mission has found stars that resemble our sun about a few million years after its birth.

The Kepler data showed many examples of what are called "superflares" - enormous explosions so rare today that we only experience them once every 100 years or so.

Yet the Kepler data also show these youngsters producing as many as 10 superflares a day.

While our sun still produces flares and CMEs, they are not so frequent or intense.

What's more, Earth today has a strong magnetic field that helps keep the bulk of the energy from such space weather from reaching Earth, the authors said.

Our young Earth, however, had a weaker magnetic field, with a much wider footprint near the poles.

This newly discovered constant influx of solar particles to early Earth may have done more than just warm the atmosphere; it may also have provided the energy needed to make complex chemicals.

In a planet scattered evenly with simple molecules, it takes a huge amount of incoming energy to create the complex molecules such as RNA and DNA that eventually seeded life.

While enough energy appears to be hugely important for a growing planet, too much would also be an issue -- a constant chain of solar eruptions producing showers of particle radiation can be quite detrimental.

Such an onslaught of magnetic clouds can rip off a planet's atmosphere if the magnetosphere is too weak.

Understanding these kinds of balances help scientists determine what kinds of stars and what kinds of planets could be hospitable for life.

The research was published in the journal Nature Geoscience.​

​Sydney, May 24 (IANS) Unlike the declining populations of many fish species, the number of cephalopods - octopus, cuttlefish and squid -- has increased in the world's oceans over the past 60 years, new research has found.

To investigate long-term trends in its abundance, the international team of researchers compiled a global database of cephalopod catch rates 

"Our analyses showed that cephalopod abundance has increased since the 1950s, a result that was remarkably consistent across three distinct groups," said study lead author Zoe Doubleday from University of Adelaide in Australia.

"Cephalopods are often called 'weeds of the sea' as they have a unique set of biological traits, including rapid growth, short lifespans and flexible development. These allow them to adapt to changing environmental conditions (such as temperature) more quickly than many other marine species, which suggests that they may be benefiting from a changing ocean environment," Doubleday said.

The research stemmed from an investigation of declining numbers of the iconic Giant Australian cuttlefish, Doubleday said.

"Surprisingly, analyses revealed that cephalopods, as a whole, are in fact increasing; and since this study, cuttlefish numbers from this iconic population near Whyalla are luckily bouncing back," Doubleday noted.

The study was published in the journal Current Biology.

Cephalopods are found in all marine habitats and, as well as being voracious predators, they are also an important source of food for many marine species, as well as humans.

"As such, the increase in abundance has significant and complex implications for both the marine food web and us," Doubleday said.​

​London, May 24 (IANS) The rise of user-generated content (UGC) - information submitted by members of the public or posted on social media - has made journalists harness a variety of new skills, thereby bringing in a sea change in the profession, a study says.

"As more news organisations move towards becoming 'digital first', the skills journalists are expected to possess have changed,” said study author Lisette Johnston from London's City University.

"They must become more "tech-savvy" … In turn, the role of the journalist itself is being redefined, as are the skills needed by newsroom staff," Johnston noted.

The study was published in the journal Digital Journalism.

To understand the evolution of journalism in the age of social media, Johnston studied how journalists from BBC World News integrated user-generated content into their reports on the conflict in Syria. She studied hours of video as well as interviewed reporters and newsroom staff.

As expected, user-generated content formed a large part of the material she studied. More than half the 35 reports or 'news packages' on Syria she analysed opened with a social media clip. 

She also found that the amount of user-generated content integrated by BBC journalists increased as the conflict wore on and reporters found access to the country more challenging.

But the increasing amount of social media content used by BBC journalists was only part of the story. The journalists to whom Johnson spoke said they felt “they had to harness a variety of new skills to enable them to "harvest" content uploaded to digital platforms”. 

They also found themselves actively engaged in "social media newsgathering" -- for images, contacts and eyewitnesses -- across multiple platforms, a practice encouraged by their managers.

Johnston's contacts also admitted that shifting through the immense volume of UGC posted online posed a huge challenge, as did verifying what was chosen -- a task made even more difficult in a war zone, where contacting the uploader of the footage could put his or her life at risk. 

Journalists had to become 'detective-like' when verifying footage found online; but even if they weren't responsible for the actual verification themselves, they had to learn how to use social media content appropriately in terms of attribution, labelling and caveats.

As for the future, “being capable of processing user-generated content and being able to navigate social media platforms which audiences inhabit are becoming core skills which journalists need to possess and maintain”, Johnston concluded.​

​New York, May 23 (IANS) Researchers have developed the first flexible wearable device that has the potential to monitor both biochemical and electric signals in the human body.

The device, which includes a flexible suite of sensors and a small electronic board, is known as the "Chem-Phys" patch and records electrocardiogram (EKG) heart signals and tracks levels of lactate -- a biochemical that is a marker of physical effort -- in real time. 

"One of the overarching goals of our research is to build a wearable tricorder-like device that can measure simultaneously a whole suite of chemical, physical and electrophysiological signals continuously throughout the day," said Patrick Mercier, professor at University of California-San Diego.

The tiny device -- made by screen printing on to a thin, flexible polymer sheet -- can be applied directly to the skin and communicates wirelessly with a phone, smart watch or laptop

The device can also transmit the data from biochemical and electrical signals via Bluetooth.

Combining information about heart rate and lactate -- a first in the field of wearable sensors -- could be especially useful for athletes wanting to improve their performance, the researchers noted. 

The teams' biggest challenge was making sure that signals from the two sensors didn't interfere with each other. 

In the study, detailed in the journal Nature Communications, the "Chem-Phys" patch was tested on three male subjects who wore the device on their chest, near the base of their sternum, while doing 15 to 30 minutes of intense activity on a stationary bike. 

Two of the subjects also wore a commercial wristband heart rate monitor. 

The data collected by the EKG electrodes on the patch closely matched the data collected by the commercial wristband. 

The device can also be helpful for physicians to monitor patients with heart disease.

"The ability to concurrently assess EKG and lactate could also open up some interesting possibilities in preventing and/or managing individuals with heart diseases," explained Kevin Patrick, a physician.

​London, May 23 (IANS) Britons are spending almost an entire day in a week online scrolling through social networking site Facebook and watching video streaming service Netflix -- driven mainly by a fear of "missing out" on what friends and colleagues are getting up to, says a study.

The study, conducted by gadget insurance provider www.row.co.uk, found that Britons spend a whopping 21 hours browsing the internet each week with over six of those solely using Facebook, Mirror.co.uk reported.

British visitors to Facebook spent 850 million hours in March this year. Of the country's 32 million Facebook users, that works out to a massive 26.5 hours per visitor every month, the report added.

"We spend hours scrolling through our timelines and catching up with what’s happening in our friends’ and families’ worlds," Zoe Cairns, founder of ZC Social Media, was quoted as saying by the website. 

“Checking our phone is a new life habit. We have a fear of logging off and missing out with what’s going on,” Cairns added.

The researchers collected data from 2,000 people for the study.

It also revealed that the average Briton spends over nine hours on Google and related services and 7.5 hours on Netflix each month.

The study also revealed that users spent an average of 58 hours 39 minutes each month browsing or using apps on smartphones, compared to 31 hours 19 minutes browsing on laptops and desktop computers.

The majority of internet users said they have happily controlled their finances on the internet.​

Phnom Penh, May 20 (IANS) The World Bank has approved $130 million worth of fresh loans to Cambodia following a five-year freeze sparked by the forced evictions of a Phnom Penh community.

New York, May 24 (IANS) An international team of scientists has detected and confirmed the faintest early-universe galaxy ever -- a finding that can help explain how the "cosmic dark ages" ended.

Using the WM Keck Observatory on the summit on Mauna Kea in Hawaii, the researchers detected the galaxy as it was 13 billion years ago.

According to Tommaso Treu, professor of physics and astronomy at University of California-Los Angeles, the discovery could be a step toward unraveling one of the biggest mysteries in astronomy -- how a period known as the "cosmic dark ages" ended.

According to the Big Bang theory, the universe cooled as it expanded. As that happened, Treu said, protons captured electrons to form hydrogen atoms, which in turn made the universe opaque to radiation -- giving rise to the cosmic dark ages.

“At some point, a few hundred million years later, the first stars formed and they started to produce ultraviolet light capable of ionizing hydrogen," Treu said.

"Eventually, when there were enough stars, they might have been able to ionize all of the intergalactic hydrogen and create the universe as we see it now,” he added.

That process, called cosmic reionization, happened about 13 billion years ago but scientists have so far been unable to determine whether there were enough stars to do it or whether more exotic sources, like gas falling onto supermassive black holes, might have been responsible.
“Currently, the most likely suspect is stars within faint galaxies that are too faint to see with our telescopes without gravitational lensing magnification," Treu said.

The new study, published in the Astrophysical Journal Letters, exploits gravitational lensing to demonstrate that such galaxies exist, and is thus an important step toward solving this mystery.

Gravitational lensing was first predicted by famous theoretical physicist Albert Einstein.

The effect is similar to that of an image behind a glass lens appearing distorted because of how the lens bends light.​