Knowledge Update

​Washington, Oct 14 (IANS) There are at least 10 times more galaxies in the observable universe than previously thought, said astronomers.

One of the most fundamental questions in astronomy is that of just how many galaxies the universe contains, and astronomers earlier estimated that the observable universe contained about 200 billion galaxies.

The new research - to be published in The Astrophysical Journal -- shows that this estimate is at least 10 times too low.

The researchers led by Christopher Conselice of University of Nottingham in Britain reached this conclusion using deep-space images from NASA's Hubble space telescope and the already published data from other teams. 

They converted the images into 3-D, in order to make accurate measurements of the number of galaxies at different epochs in the universe's history. 

In addition, they used new mathematical models, which allowed them to infer the existence of galaxies that the current generation of telescopes cannot observe. 

This led to the surprising conclusion that in order for the numbers of galaxies we now see and their masses to add up, there must be a further 90 per cent of galaxies in the observable universe that are too faint and too far away to be seen with present-day telescopes. 

These myriad small faint galaxies from the early universe merged over time into the larger galaxies we can now observe.

"It boggles the mind that over 90 per cent of the galaxies in the universe have yet to be studied. Who knows what interesting properties we will find when we discover these galaxies with future generations of telescopes? In the near future, the James Webb Space Telescope will be able to study these ultra-faint galaxies," Conselice said.

"These results are powerful evidence that a significant galaxy evolution has taken place throughout the universe's history, which dramatically reduced the number of galaxies through mergers between them - thus reducing their total number," Conselice explained.

The decreasing number of galaxies as time progresses also contributes to the solution for Olbers' paradox (first formulated in the early 1800s by German astronomer Heinrich Wilhelm Olbers): Why is the sky dark at night if the universe contains an infinity of stars? 

The team came to the conclusion that indeed there actually is such an abundance of galaxies that, in principle, every patch in the sky contains part of a galaxy.

However, starlight from the galaxies is invisible to the human eye and most modern telescopes due to other known factors that reduce visible and ultraviolet light in the universe.

Those factors are the reddening of light due to the expansion of space, the universe's dynamic nature, and the absorption of light by intergalactic dust and gas. 

All combined, this keeps the night sky dark to our vision, the researchers said.

Wellington, Oct 14 (IANS) Vitamins A and C could improve the conversion of adult cells into stem cells, opening the way to advances in biomedical treatments for human diseases, according to a New Zealand-led study released on Friday.

The research team discovered that the two vitamins complemented each other in erasing "memory" associated with DNA, an important effect for improving technologies geared towards regenerative medicine and stem cell therapy, Xinhua news agency reported.

Ordinary adult cells, such as those in the skin or blood, could be artificially coerced in a culture dish to resemble embryos only a few days old, said study co-author Tim Hore of the University of Otago.

Since the 2006 discovery that reprogramming was possible, there had been much interest in using induced embryonic stem cells to cure human disease.

"However, hampering these efforts is the reality that adult cells are resistant to changes in their identity, partly because of chemical alterations to their DNA," Hore said in a statement.

These alterations, known as "DNA methylation", were acquired during development and provided a form of cellular memory that helped cells faithfully maintain a specialised function.

Removal of this memory was critical in order to create a developmentally potent stem cell, or to change one kind of adult cell to another.

With collaborators in Britain and Germany, Hore determined that adding vitamins A and C to culture dishes removed DNA methylation from embryonic stem cells.

When applied to cells during the reprogramming process, those with the desired "naive" embryonic characteristics were created in much greater numbers, he said.

"We found that both vitamins affect the same family of enzymes which actively remove DNA methylation. It turns out that vitamin A increases the number of these enzymes within the cell and vitamin C enhances their activity," he said.

In addition to regenerative medicine, the work could have implications for other areas of biomedical importance.

Loss of DNA methylation and cellular memory were a hallmark of certain cancers, so a better understanding of how this process occurred could prove significant.

New York, Oct 14 (IANS) Combining the tools of Big Data analysis and visualisation with the vast amounts of data generated by social media, a group of scientists from Indiana University has started to tackle new areas of health research.

"We try to find the commonality between biological, social, and technological networks, and the internet. Previous studies -- whether in hospitals or by sociologists -- could handle only 20, 30 or 40 patients in a study," said Luis Rocha, principal investigator of the Complex Adaptive Systems and Computational Intelligence (CASCI) group at Indiana University.

"Software is now driving our research, so through social media we can plug into millions and millions of people worldwide with very different types of conditions. This helps us tap into the psychological and social elements of healthcare, making this a major game changer," Rocha said.

The researchers partnered with Pune-based Persistent Systems, a provider of large-scale software-driven healthcare solutions, to develop sophisticated algorithms to analyse the connection between medicine and social behaviour in health issues, particularly how they are discussed across social media. 

For example, in looking at the analysis of depression, millions of posts are first analysed based on defined hashtags with the relevant drug names across social media channels such as Instagram, Facebook, or Twitter. 

The algorithms find connections on how drugs interact with each other, and how people are describing them, while also looking for clusters of symptoms at a scale not previously possible. 

Identifying and validating new clusters of drugs, natural products and symptoms can act as an early warning system for adverse drug effects and interactions.

The methodology also allows the study of multiple health issues with distinct social attitudes, such as depression and epilepsy.

Another goal is to allow health specialists to visualize and interact with the data in three dimensions, allowing them to study cohort and individual behaviours in much detail in a virtual reality setting. 

"Tapping into the scale of social networks offers an incredible source of consumer and patient data, opening up a whole new type of software-driven solution," Sid Chatterjee, Chief Technology Officer at Persistent Systems, said.

​New York, Oct 14 (IANS) A team of US researchers has developed a reliable and accurate navigation system that exploits existing environmental signals such as cellular and Wi-Fi rather than the Global Positioning System (GPS).

The technology can be used as a stand-alone alternative to GPS or complement current GPS-based systems to enable highly reliable, consistent and tamper-proof navigation. 

The technology could also be used to develop navigation systems that meet the stringent requirements of fully autonomous vehicles, such as driverless cars and unmanned drones, said the team from University of California, Riverside. 

"Our goal is to get autonomous vehicles operate with no human-in-the loop for prolonged periods of time, performing missions such as search, rescue, surveillance, mapping, farming, firefighting, package delivery and transportation," said Zak Kassas, assistant professor of electrical and computer engineering.

Most navigation systems in cars and portable electronics use the space-based Global Navigation Satellite System (GNSS). 

For precision technologies, such as aerospace and missiles, navigation systems typically combine GPS with a high-quality on-board Inertial Navigation System (INS).

Despite advances in this technology, current GPS/INS systems will not meet the demands of future autonomous vehicles for several reasons. 

GPS signals alone are extremely weak and unusable in certain environments like deep canyons.

"Civilian GPS signals are unencrypted, unauthenticated, and specified in publicly available documents, making them hackable," the researchers noted.

Instead of adding more internal sensors, Kassas and his team have been developing autonomous vehicles that could tap into the hundreds of signals around us at any point in time, like cellular, radio, television, Wi-Fi and other satellite signals.

The system can be used to supplement INS data in the event that GPS fails. 

The team presented its research at the 2016 Institute of Navigation Global Navigation Satellite System Conference (ION GNSS+), in Portland, Oregon recently.

​New York, Oct 14 (IANS) Young kids who miss daytime nap and also stay up late at night are likely to consume more calories, suggests new research.

​London, Oct 13 (IANS) In a move aimed at fostering peace, opening up access to space technologies and offering protection for citizens of planet Earth, a team of scientists and legal experts unveiled proposals for the "first nation state in space", media reported.

The "new nation" -- dubbed "Asgardia" after one of the mythical worlds inhabited by the Norse gods -- will eventually become a member of the United Nations, with its own flag and anthem devised by members of the public through a series of competitions, according to the team, the Guardian reported on Wednesday.

Asgardia "will offer an independent platform free from the constraint of a land-based country's laws," according to the project website.

"For the first time in history a new nation state has been created -- not on Earth but in the heavens above," read a statement at asgardia.space

"Asgardia is the prototype of a free and unrestricted society which holds knowledge, intelligence and science at its core along with the recognition of the ultimate value of each human life," it said.

According to the project website any human living on Earth can become a citizen of Asgardia.

"You can join like-minded people on this new exciting step in fostering an extended future for humankind," it said.

Initially, it would seem, this new nation will consist of a single satellite, scheduled to be launched next year.

"Physically the citizens of that nation state will be on Earth; they will be living in different countries on Earth, so they will be a citizen of their own country and at the same time they will be citizens of Asgardia," project lead Igor Ashurbeyli, told the Guardian.

"When the number of those applications goes above 100,000 we can officially apply to the UN for the status of state," Ashurbeyli, a Russian businessman and nanoscientist who also founded the Vienna-based Aerospace International Research Center and is currently Chairman of Unesco's Science of Space committee, added.

Washington, Oct 13 (IANS) An iPad app, designed specifically for use in space, simplifies the way astronauts track their dietary intake and offers greater insight for physicians and researchers on the Earth looking to keep crews healthy and fit, NASA said.

The International Space Station Food Intake Tracker (ISS FIT) iPad app, recently delivered to the space station, gives astronauts real-time feedback about their dietary habits.

"Understanding the relationship of diet with crew health is critical for future exploration missions, where nutrition will be a key countermeasure in mitigating the negative effects of spaceflight on the body," Scott M. Smith, nutritionist at NASA, said in a statement.

"We've recently documented that astronauts can protect their bones with good nutrition and exercise," Smith said. 

"This app puts the tools in their hands to track this information in real time," Smith explained.

The app does not require internet access to sync with the food database - that includes foods available on the space station, including those from international partner agencies - as many of the apps available on Earth require, NASA said.

The app reports nutrients specifically of concern for astronauts (and often terrestrial beings), ensuring adequate calorie consumption, minimising sodium intake and maintaining hydration to reduce kidney stone risk.

The app, developed through NASA's Center of Excellence for Collaborative Innovation, used crowdsourcing techniques hosted by TopCoder. 

Designed for use on the space station, the solution had to meet strict criteria, offer multiple user options and work without internet connectivity. 

The app allows crew members to record foods available on the space station. It gives astronauts options to record foods from a checklist, search tool, using audio recording, taking photos or scanning barcodes, if available.

The app provides real-time information on key nutrients including calories, sodium and fluid, allowing crew members to see at lunch that they need to consume more water later in the day, for example. 

The app replaces a weekly computer questionnaire, which provided an estimate of dietary intake over the week. 

The detailed data not only helps crews in real time each day, but also will allow for more detailed assessments of dietary intake during flight and relating these to other crew health concerns like bone loss and vision changes, NASA said.

​New York, Oct 13 (IANS) Children of mothers who used anti-depressants during pregnancy are at increased risk of having speech or language disorders, warns a new study.

"To our knowledge, this is the first study to examine the relationship between maternal anti-depressant use and speech/language, scholastic, and motor disorders in offspring," said one of the researchers Alan Brown, Professor at Columbia University's Mailman School of Public Health.

Mothers who purchased anti-depressants at least twice during pregnancy had a 37-percent increased risk of speech and/or language disorders among their offspring compared to mothers with depression and other psychiatric disorders who were not treated with anti-depressants, the findings showed.

"We believe that our finding about children of mothers who purchased at least two SSRI prescriptions during pregnancy is particularly meaningful because these women are more likely to have taken these medications, and more likely to have been exposed for a longer period and to larger amounts of the SSRI in pregnancy, compared to women who filled only one prescription," Brown noted. 

The speech/language disorders included expressive and receptive language disorders and those involving articulation of sounds.

"The study benefited from large sample population and followed the children beyond age three," Brown said.

Selective serotonin reuptake inhibitors (SSRIs) -- most commonly prescribed anti-depressants -- such as fluoxetine, citalopram, paroxetine, sertraline, fluvoxamine, and escitalopram may cross the placenta and enter the fetal circulation. 

The researchers examined a sample of 845,345 single, live births between 1996 and 2010 taken from national registries in Finland.

The exposure groups were classified as mothers who purchased SSRIs once or more before or during pregnancy; those diagnosed with a psychiatric disorder one year before or during pregnancy but did not purchase anti-depressants; and mothers who neither purchased anti-depressants nor were given depression-related diagnoses.

In the whole sample, the risk of speech/language disorders was increased among offspring of mothers who used SSRI during pregnancy, showed the study published online in the journal JAMA Psychiatry.

​New York, Oct 12 (IANS) A drug commonly used for the prevention of allergies and asthma has shown promise in preventing liver disease and reducing the need for transplants, says a study.

The study, conducted in mice, found that cromolyn sodium successfully blocked a series of cells that trigger liver scarring (known as fibrosis), which in advanced cases can lead to cirrhosis. 

The research was a direct outgrowth of previous published works involving the same drug for bile duct damage and liver cancer.

"If you base it off these studies, the possibility of reducing or preventing fibrosis in patients could be very high," said one of the researchers, Heather Francis from Baylor Scott & White Health in Texas, US.

The finding, published in the journal Hepatology, could most impact patients with primary sclerosing cholangitis (PSC), a chronic disease that damages bile ducts and causes serious liver damage.

The disease has no effective treatments and leaves patients with few options beyond a liver transplant.

In particular, the study evaluated mast cells (MCs), which are known to infiltrate and multiply after liver injury and release histamine, which causes fibrosis. 

Using a model that mimics human primary sclerosing cholangitis, researchers found that the drug successfully blocked that histamine, which in turn reduced fibrosis.

"Given the limited treatment options for PSC patients, we are thrilled with these study insights," Gianfranco Alpini, Director of the Digestive Disease Research Center at Baylor Scott & White, said.

"We need to perform additional experiments to ensure that we are giving a dose that would be tolerable to humans," Francis pointed out.

​Canberra, Oct 10 (IANS) An Australian researcher has devised a new high-tech UV-sensitive patch that changes colour when it is time to reapply sunscreen.

Queensland University of Technology (QUT's) Institute of Health and Biomedical Innovation lead researcher Dr Elke Hacker said on Monday in a statement that the research aims to help 75 per cent of young Australians who get sunburned every year that possibly contracts skin cancer, Xinhua news agency reported.

"Sunscreen when applied at the correct concentration (2mg/cm2) is effective at blocking the harmful effects of ultraviolet radiation. However, the concentration applied in real life conditions is usually less, which provides inadequate protection," Hacker said.

"Currently the most common way to assist people to determine how long they can safely stay in the sun after sunscreen application is time-based on the two hour reapply recommendation."

"However, what we are seeing is despite doing their best to stay sun safe and sunburn-free, people get either the concentration or the timing wrong resulting in a damaging dose of ultraviolet radiation," she said.

Hacker will lead a pilot study looking at the usability of a newly developed wearable UV indicator that takes away the guesswork in how much sunscreen to apply and when to reapply by changing colour to warn wearers their sunscreen is no longer effective.

"As part of our study we are looking for Brisbane-based volunteers to test a patch before we undertake a larger trial to determine if it can reduce the incidence of sunburn," Hacker said.

"Participants will be asked to test the patch for a seven day period and attend two focus groups sessions at the start and end of the study," she said.

Hacker said UV radiation or sunlight exposure was the main environmental risk factor for skin cancer.

"What we know is that sunburn rates are high, especially among younger people, with more than 72 per cent of Queenslanders aged 18 to 24 years admitting to getting sunburnt," she said.

"The sun-smart messages are getting through to Queenslanders but the concern is that high rates of sunburn are caused because people are unaware when dangerous UV levels have been reached."

"This device seeks to give real-time information that can help change unhealthy sun exposure habits," she said.