Knowledge Update

Beijing, April 12 (IANS) Over 80 percent of groundwater in China is polluted and not fit for human consumption.

In its most recent monthly report, published on Monday, the water resources ministry said that of 2,103 monitored wells, water from 691, or 32.9 percent, was defined as Class

​London, April 12 (IANS) A team of scientists led by Oxford University has made a discovery that can improve chances of developing an effective vaccine against Tuberculosis (TB).

The researchers identified new biomarkers for TB which have shown for the first time why immunity from the widely used BCG vaccine is so variable. 

The biomarkers will also provide valuable clues to assess whether potential new vaccines could be effective, the team said.

TB remains one of the world's major killer diseases. The only available BCG vaccine works well (estimated 50 percent effective) to prevent severe disease in children but is very variable (0 percent to 80 percent effective) in adults.

With a pressing need for a TB vaccine that is more effective than BCG, the Oxford team working with colleagues from the University of Cape Town and the London School of Hygiene and Tropical Medicine set out to identify immune correlates that could facilitate TB vaccine development. 

The team, led by professor Helen McShane and Dr Helen Fletcher, studied immune responses in infants in South Africa who were taking part in a TB vaccine trial.

The team carried out tests for 22 possible factors. 

“These are useful results. They show that antigen-specific T cells are important in protection against TB but that activated T cells increase the risk,” explained professor McShane from Oxford in a paper that appeared in the journal Nature Communications.

“For the first time we have some evidence of how BCG might work and also what could block it from working. Although there is still much work to do, these findings may bring us a step closer to developing a more effective vaccine for TB,” added Dr Fletcher from the London School of Hygiene and Tropical Medicine.

The team is working to develop an effective TB vaccine aimed at protecting more people from the disease.​

​New York, April 13 (IANS) World-renowned British astrophysicist Stephen Hawking on Tuesday teamed up with Russian billionaire Yuri Milner and Facebook founder Mark Zuckerberg in a $100 million effort to make tiny spaceships capable of interstellar space travel.

Hawking and Milner made the joint announcement at a press conference held at One World Observatory in New York City on Tuesday, Xinhua reported.

The project, dubbed "Breakthrough Starshot," is a research and engineering programme that aims to build laser beam propelled "nanocrafts" that can travel at 20 percent of lightspeed -- more than 1,000 times faster than current fastest spacecraft.

According to Milner, once the "nanocrafts" are built, they could reach Alpha Centauri, a star 4.37 light-years away, approximately 20 years in a fly-by mission.

Alpha Centauri is one of the closest star systems to the solar system and the current fastest spacecraft would have to spend 30,000 years to get there.

The "nanocrafts" are gram-scale robotic spacecrafts consisting of two main parts: a computer CPU sized "StarChip" and a "Lightsail" made with metamaterials no more than a few hundred atoms thick.

Although weighing just a few grams, the "StarChip" is a fully functional space probe, which carries various equipment including cameras, navigation and communication.

"The 'StarChip' can be mass-produced at the cost of an iPhone," Milner said.

The "nanocrafts" can then be propelled into space by a powerful laser beam, which according to Avi Loeb, a theoretical physicist and panelist at the news conference, will carry a power of 100 gigawatt.

"This is the power needed to lift off a space shuttle," Loeb said.

Milner and the scientists believe that with the rising power and falling costs of lasers, the entire process is practical within a couple of years.

"Fifteen years ago, it would not have made sense to make this investment. Now we have looked at the numbers, and it does," Milner said.

The project was part of the Breakthrough Initiatives first launched in July 2015 by Hawking and Milner, including a series of research plans to scan the 100 galaxies closest to the Milky Way in search for aliens. "Starshot" is its newest endeavor.

Hawking believes that human's innate sense to transcend limits is the driving force behind the project. "Gravity pins us to the ground, but I just flew to America."

While one cannot hear the joking tone through Hawking's voice synthesizer, his humour had been easily received.

What the scientists are looking for is not just reaching Alpha Centauri, but what can be learned during the efforts.

"A lot of science will be learned by the process of going through this, making this happen," said panelist Mae Jemison, a former NASA astronaut. 

"There is big task ahead, there's a big leap in getting something of a micro size to go at some percentage of the speed of light. That will have all kinds of reverberations."

Tuesday also marked the 55th anniversary of the first human space flight by Russian cosmonaut Yuri Gagarin.

"Today we commit to this next great leap into the cosmos because we are human and our nature is to fly," Hawking said.​

New York, April 13 (IANS) An image taken in 1917 and kept on an astronomical glass plate with the Carnegie Institution for Science (CIS) has revealed the first-ever evidence of a planetary system beyond our own Sun.

The unexpected find was recognised in the process of researching an article about planetary systems surrounding white dwarf stars in the journal New Astronomy Reviews.

The Review's author Jay Farihi from University College London and Carnegie Observatories' director John Mulchaey were looking for a plate in the Carnegie archive that contained a spectrum of van Maanen's star.

It is a white dwarf discovered by Dutch-American astronomer Adriaan van Maanen in the very year the plate was made.

Stellar spectra images allowed 19th century astronomers to develop a system for classifying stars that is still used today. 

Modern astronomers use digital tools to image stars but for decades, they would use glass photographic plates both to take images of the sky, and to record stellar spectra.

When Farihi examined the spectrum, he found something quite extraordinary.

Carnegie's 1917 spectrum of van Maanen's star revealed the presence of heavier elements such as calcium, magnesium, and iron, which should have long since disappeared into the star's interior due to their weight.

Astronomers now know that that van Maanen's star and other white dwarfs with heavy elements in their spectra represent a type of planetary system featuring vast rings of rocky planetary remnants that deposit debris into the stellar atmosphere. 

“The unexpected realisation that this 1917 plate from our archive contains the earliest recorded evidence of a polluted white dwarf system is just incredible,” said Mulchaey. 

Planets themselves have not yet been detected orbiting van Maanen's star, nor around similar systems, but Farihi is confident it is only a matter of time.

Carnegie has one of the world's largest collections of astronomical plates with an archive that includes about 250,000 plates from three different observatories.

“We have a ton of history sitting in our basement and who knows what other finds we might unearth in the future?” asked Mulchaey.

New York, April 12 (IANS) Infants' brains can understand what they are observing and thus can copy other people's action, finds a new study providing the first evidence that directly links neural responses from the motor system to overt social behaviour in infants.

Babies understand what they are observing. There is a direct connection between observing others, understanding what others are doing, and learning how to act -- abilities which are often disrupted in developmental disabilities, including autism, the researchers said.

Like adults, infants show this response when acting themselves and when watching others' actions, suggesting that the motor system of babies may play a role in the perception of others' actions, the researchers pointed out. 

"Our research provides initial evidence that motor system recruitment is contingently linked to infants' social interactive behaviour," said lead author Courtney Filippi, doctoral candidate at the University of Chicago in the US. 

The findings showed that recruiting the motor system during action encoding predicts infants' subsequent social interactive behaviour, the researchers stated.

"This understanding on the part of a baby involves not just seeing the other person's action, but also involves the baby's own motor system, which is recruited when he or she chooses the same toy," said Helen Tager-Flusberg, professor at Boston University in the US, who was not involved in the research. 

The study, published in the journal Psychological Science, showed that by the middle of their first year of life, babies begin to understand that people act intentionally.

"Here we looked at the development of social cognition, social behaviour, and the motor system, all of which are critical for human development and are often disrupted in developmental disabilities, including autism," explained co-author Amanda Woodward, professor at the Chicago University.

For the study, the team involved 36 seven-month-old infants, whose brain activity was measured using electroencephalography (EEG), during an experiment, where each infant had to observe a person reaching out to a toy. 

Babies' brain activity predicted how they would respond to the person's behaviour.

When the infants recruited their motor system while observing the person grasp the toy, they subsequently imitated him. 

When they didn't imitate the person, there was no detectable engagement of the motor system in their brain activity as they watched him.​

Washington, April 13 (IANS) The first expandable habitats for astronauts that may help set the design of deep space habitats including on Mars is set to be installed to the International Space Station (ISS) on April 16.

Expandable habitats are designed to take up less room on a rocket but provide greater volume for living and working in space once expanded.

This first test of an expandable module will allow investigators to gauge how well the habitat performs overall and how well it protects against solar radiation, space debris and the temperature extremes of space.

Once the test period is over, BEAM will be released from the space station and will burn up during its descent through Earth's atmosphere.

The Bigelow Expandable Activity Module (BEAM) will be attached to the station's Tranquility module over a period of about four hours, the US space agency said in a statement.

Using the robotic arm, ground controllers at NASA's Johnson Space Center in Houston will remove BEAM from the unpressurised trunk of SpaceX's Dragon spacecraft.

NASA astronauts aboard the station will secure BEAM using common berthing mechanism controls.

BEAM was launched aboard Dragon spacecraft from Cape Canaveral Air Force Station in Florida on April 8.

At the end of May, the module will be expanded to nearly five times its compressed size of 7 feet in diameter by 8 feet in length to roughly 10 feet in diameter and 13 feet in length.

Astronauts will first enter the habitat about a week after expansion and, during a two-year test mission, will return to the module for a few hours several times a year to retrieve sensor data and assess conditions.

The BEAM project is co-sponsored by NASA's Advanced Exploration Systems Division and Bigelow Aerospace.​

Sydney, April 12 (IANS) A team of researchers has demonstrated that a new plant-derived drug can block the progression of multiple sclerosis.

Multiple Sclerosis (MS) is a disease that affects the brain and spinal cord and is also a chronic incurable condition marked by attacks that bring gradual deterioration in the patient's health. It has affected nearly 2.5 million people worldwide.

The new drug -- named T20K -- was extracted from a traditional medicinal plant, the Oldenlandia affinis.

"This is a really exciting discovery because it may offer a whole new quality of life for people with this debilitating disease," said Christian Gruber, researcher at University of Queensland in Australia. 

The findings demonstrated in an animal model showed that T20K stopped progression in the normal clinical symptoms of MS.

The new treatment arose from a synthesised plant peptide, a class of drugs known as cyclotides.

"Cyclotides are present in a range of common plants, and they show significant potential for the treatment of auto immune diseases," Gruber noted in the paper published in the journal PNAS.

The new drug is to be taken by mouth, in contrast to some current MS treatments where patients need to have frequent injections.

"The T20K peptides exhibit extraordinary stability and chemical features that are ideally what you want in an oral drug candidate," Gruber stated.

The breakthrough could be a step forward in preventing and treating MS and other autoimmune diseases, the researchers concluded.​

​Washington, April 9 (IANS) US space firm SpaceX resumed its resupply mission to the International Space Station (ISS) on Friday, carrying aboard an experimental inflatable space habitat that might be crucial for future deep space explorations.

The California-based company also made history by landing the first stage of its Falcon 9 rocket on a droneship in the Atlantic Ocean, after it launched the Dragon spacecraft at 4:43 p.m. (2043 GMT) from Cape Canaveral Air Force Station in Florida, Xinhua reported.

This was SpaceX's eighth cargo mission to the ISS. It also marked the first flight of Dragon to the ISS since June, when the Falcon 9 rocket exploded about two minutes after liftoff.

As usual, SpaceX attempted to land the Falcon 9's first stage on the "Of Course I Still Love You" droneship, which was stationed in the Atlantic Ocean off the Florida coast.

Minutes later, the company posted a photo via Twitter in which the first stage was clearly seen standing on the deck of the ship.

It is the first time SpaceX has been able to stick a landing on a droneship after four previous such attempts ended in failure. It also achieved one successful soft landing on a land-based pad at Cape Canaveral in December last year.

What is different this time was "the rocket landed instead of putting a hole in the ship or tipping over. So we are really excited about that," said SpaceX founder Elon Musk at a press conference after the landing.

NASA offered a congratulation via Twitter to SpaceX for the successful landing and sending the unmanned Dragon to the orbiting laboratory.

Among the almost 7,000 pounds (3,200 kilograms) of items inside the Dragon spacecraft is the 3,100-pound (1,400-kilogram) Bigelow Expandable Activity Module (BEAM), a $17.8-million project that will be attached to the ISS to test the use of an inflatable space habitat in microgravity.

"It is the future," said Kirk Shireman, manager of NASA's ISS programme. 

"Humans will be using these kinds of modules as we move further and further off the planet and actually as we inhabit low Earth orbit."

According to NASA, inflatable habitats greatly decrease the amount of transport volume at launch for future space missions and take up less room on a rocket, but once set up, provide additional volume for living and working.

Shireman said the company that developed BEAM, Bigelow Aerospace, launched two inflatable modules about 10 years ago using Russian rockets but this will be the first time humans will interact with such a module.

After being attached to the ISS, BEAM will be filled with air to expand it for a two-year test period in which ISS astronauts will conduct a series of tests to validate overall performance and capability of expandable habitats.

BEAM is 5.7 feet (1.7 meters) long and 7.75 feet (2.4 meters) in diameter when packed; 12 feet (3.7 meters) long and 10.5 feet (3.2 meters) in diameter when expanded, with 565 cubic feet (16 cubic meters) of interior volume.

Bigelow Aerospace is also developing a new inflatable module called B330, which is 20 times larger than BEAM, and hopes to put two B330s together in orbit into a private space station in 2020, Robert Bigelow, the company's president, told reporters.

"We are in the early phase of a new kind of spacecraft that offers a lot of promise," Bigelow said.

The cargo also included new experiments that will help investigators study muscle atrophy and bone loss in space, seek insight into the interactions of particle flows at the nanoscale level and use protein crystal growth in microgravity to help design new drugs.

SpaceX is one of two US companies that provide ISS cargo services for NASA. The other company is Orbital ATK, whose Cygnus capsule was launched to the ISS on March 22.

It is the first time that both companies' cargo ships will be docked at the orbiting lab simultaneously.​

​London, April 9 (IANS) Nearly six-10 million years ago, the central Arctic was completely ice-free during summer and sea-surface temperature reached values of four to nine degrees Celsius, an international team of scientists has revealed.

They used unique sediment samples from the Lomonosov Ridge -- a large undersea mountain range in the central Arctic, while travelling on board Germany's research icebreaker RV Polarstern in 2014. 

"The Arctic sea ice is a very critical and sensitive component in the global climate system. It is therefore important to better understand the processes controlling present and past changes in sea ice," said study lead author Ruediger Stein from the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI).

"One of our expedition's aims was to recover long sediment cores from the central Arctic, that can be used to reconstruct the history of the ocean's sea ice cover throughout the past 50 million years," Stein added.

Although the recovered sediment cores were only four to eight metres long, one of them turned out to be precisely one of those climate archives that the scientists had been looking for a long time. 

"With the help of certain microfossils, so-called dinoflagellates, we were able to unambiguously establish that the lower part of this core consists of approximately six to eight million-year-old sediments, thereby tracing its geological history back to the late Miocene," Stein said.

With the help of so-called "climate indicators or proxies", the scientists were able to to reconstruct the climate conditions in the central Arctic Ocean for a time period for which only very vague and contradictory information was available. 

The study, published in the journal Nature Communications, however, said that in spring, autumn and winter the ocean was covered by sea ice of variable extent.

"By combining our data records on surface water temperature and on sea ice, we are now able to prove for the first time that six to ten million years ago, the central Arctic Ocean was ice-free in the summer," Stein said. 

"In the spring and the preceding winter, on the other hand, the ocean was covered by sea ice. The seasonal ice cover around the North Pole must have been similar to that in the Arctic marginal seas today," he noted.​

​London, April 9 (IANS) Obesity and poor nutrition in mothers during pregnancy can affect the egg reserves of their female children, which can increase the risk of fertility problems, a study has found.

The researchers claimed this understanding to be the first step towards devising interventions to protect the fertility of females who experienced very difficult womb environments in the study conducted on mice.

"Infertility can have devastating impacts on individuals and families, and our study will help to better identify women who are at risk of experiencing problems with their fertility," said Catherine Aiken from University of Cambridge in Britain. 

"We hope to be able to devise ways to maintain future fertility for children who faced a very difficult nutritional environment in the womb," Aiken added in the paper published in the journal The FASEB.

This finding improves scientific understanding of the long-term, generational, effects of obesity and poor nutrition.

The team used mice and fed them with either a high-fat and high-sugar (obesogenic) diet or a normal healthy diet during pregnancy. After which, their female offspring were weaned onto the same obesogenic diet or normal diet. 

The results revealed that low egg reserves in all of the daughters whose mothers ate a high-fat and high-sugar diet, regardless the daughters' diet.

To find the cause of the low egg reserves, researchers examined the ovaries of the daughters and discovered changes that disrupted the normal protection against damaging free radicals in the ovaries, as well as energy production.

"It has of course long been known that the intrauterine environment is critical and also that maternal nutritional deprivation in particular can have very adverse effects on the offspring," said another researcher Thoru Pederson.

"However, this study shows that caloric excess also has adverse consequences and that to an extent it can affect is reduced ovulation, it constitutes a transgenerational defect that would be evolution”rily severe," Pederson explained.

Although rodent models can be different, it seems likely that these finding would translate to the humans and indeed such studies seeking this correlation would be highly warranted, the researchers suggested.​