Knowledge Update

​Toronto, Dec 9 (IANS) Smallpox, a pathogen that caused millions of deaths worldwide, may not be an ancient disease but a much more modern killer that went on to become the first human disease eradicated by vaccination, suggests genetic research.

Smallpox, one of the most devastating viral diseases ever to strike humankind, had long been thought to have appeared in human populations thousands of years ago in ancient Egypt, India and China, with some historical accounts suggesting that Pharaoh Ramses V - who died in 1145 BC -- suffered from smallpox.

The new findings, published in the journal Current Biology, fuel a longstanding debate over when the virus that causes smallpox, variola, first emerged and later evolved in response to inoculation and vaccination.

"This study sets the clock of smallpox evolution to a much more recent time-scale" said Eddie Holmes, Professor at the University of Sydney, Australia.

In an attempt to better understand its evolutionary history, and after obtaining clearance from the World Health Organisation (WHO), the team of scientists extracted the heavily fragmented DNA from the partially mummified remains of a Lithuanian child.

The child is believed to have died between 1643 A.D. and 1665 A.D., a period in which several smallpox outbreaks were documented throughout Europe with increasing levels of mortality. 

The smallpox DNA was captured, sequenced and the ancient genome, one of the oldest viral genomes to date, was completely reconstructed. 

Researchers compared and contrasted the 17th century strain with those from a modern databank of samples dating from 1940 up to its eradication in 1977. 

Strikingly, the research showed that the evolution of smallpox virus occurred far more recently than previously thought, with all the available strains of the virus having an ancestor no older than 1580.

"So now that we have a timeline, we have to ask whether the earlier documented historical evidence of smallpox, which goes back to Ramses V and includes everything up to the 1500s, is real," senior author of the study Hendrik Poinar from McMaster University in Hamilton, Canada, said.

"Are these indeed real cases of smallpox, or are these misidentifications, which we know is very easy to do, because it is likely possible to mistake smallpox for chicken pox and measles," Poinar pointed out.

"It is still unclear what animal is the true reservoir of smallpox virus and when the virus first jumped into humans," Holmes noted.

​Nay Pyi Taw, Dec 9 (IANS) In one-of-a-kind discovery, a tail of a feathered dinosaur has been found perfectly preserved in amber in Myanmar, opening a new window on the biology of a group that dominated earth for more than 160 million years, a media reported on Friday.

Described in the journal Current Biology, the examination of the specimen suggests the tail was chestnut brown on top and white on its underside.

"This is the first time we've found dinosaur material preserved in amber," co-author Ryan McKellar, of the Royal Saskatchewan Museum in Canada, told the BBC news.

The study's first author, Lida Xing from the China University of Geosciences in Beijing, discovered the remarkable fossil at an amber market in Myitkina, Myanmar.

The 99-million-year-old amber had already been polished for jewellery and the seller had thought it was plant material. On closer inspection, however, it turned out to be the tail of a feathered dinosaur about the size of a sparrow.

McKellar said examination of the tail's anatomy showed it definitely belonged to a feathered dinosaur and not an ancient bird.

"We can be sure of the source because the vertebrae are not fused into a rod or pygostyle as in modern birds and their closest relatives," he explained.

"Instead, the tail is long and flexible, with keels of feathers running down each side."

McKellar said there are signs the dinosaur still contained fluids when it was incorporated into the tree resin that eventually formed the amber. This indicates that it could even have become trapped in the sticky substance while it was still alive.

Co-author Prof Mike Benton, from the University of Bristol, added: "It's amazing to see all the details of a dinosaur tail - the bones, flesh, skin, and feathers - and to imagine how this little fellow got his tail caught in the resin, and then presumably died because he could not wrestle free."

The findings also shed light on how feathers were arranged on these dinosaurs, because 3D features are often lost due to the compression that occurs when corpses become fossils in sedimentary rocks.

The feathers lack the well-developed central shaft - a rachis - known from modern birds. Their structure suggests that the two finest tiers of branching in modern feathers, known as barbs and barbules, arose before the rachis formed.

Paul Barrett, from London's Natural History Museum, called the specimen a "beautiful fossil", describing it as a "really rare occurrence of vertebrate material in amber".

He told BBC news: "Feathers have been recovered in amber before, so that aspect isn't new, but what this new specimen shows is the 3D arrangement of feathers in a Mesozoic dinosaur/bird for the first time, as almost all of the other feathered dinosaur fossils and Mesozoic bird skeletons that we have are flattened and 2D only, which has obscured some important features of their anatomy."

​Washington, Dec 9 (IANS) US researchers said on Thursday they have discovered a tumour in a 255-million-year-old mammalian ancestor called a gorgonopsian.

The tumour, found in the extinct species's fossilised jaw, is a benign one made up of miniature, tooth-like structures, they reported in the latest issue of Journal of the American Medical Association Oncology.

Known as a compound odontoma, this type of tumour is common to mammals today. Before this discovery, the earliest known evidence of odontomas came from Ice Age-era fossils, Xinhua reported.

"We think this is by far the oldest known instance of a compound odontoma," said senior author Christian Sidor, a University of Washington (UW) professor of biology and curator of vertebrate paleontology at the Burke Museum of Natural History and Culture. "It would indicate that this is an ancient type of tumour."

According to the study, gorgonopsians were distant mammal relatives and the top predators the apex predator during its pre-dinosaur era about 255 million years ago. 

These animals are part of a larger group of animals called synapsids, which includes modern mammals as its only living member.

Sidor and colleagues spotted the tumour when they examined wafer-thin slices of the fossilised gorgonopsian jaw, collected in southern Tanzani, to see how the tooth was nestled within its socket.

They immediately noticed irregular clusters of up to eight tiny, round objects embedded next to the root of a canine tooth. The objects within each cluster resembled small, poorly differentiated teeth, or toothlets, that harboured distinct layers of dentin and enamel.

"At first we did not know what to make of it," said Megan Whitney, lead author and UW biology graduate student. "But after some investigation we realized this gorgonopsian had what looks like a textbook compound odontoma."

In humans and other mammals, the tumour's toothlets grow within the gums or other soft tissues of the jaw and can cause pain and swelling, as well as disrupt the position of teeth and other tissues, the researchers said.

Odontomas are considered benign tumours because they do not metastasize and spread throughout the body. But given the disruptions they cause, surgeons often opt to remove them.

"Until now, the earliest known occurrence of this tumour was about one million years ago, in fossil mammals," said Judy Skog, programme director in the National Science Foundation's Division of Earth Sciences, which funded the research.

"These researchers have found an example in the ancestors of mammals that lived 255 million years ago. The discovery suggests that the suspected cause of an odontoma is not tied solely to traits in modern species, as had been thought," Skog added.

​Kathmandu, Dec 8 (IANS) Nepal's state-owned telecom company Nepal Telecom and China Telecom Global have signed an agreement on providing internet protocol service between the two countries through cross-border Terrestrial Cable Route, the company said.

​Tehran, Dec 7 (IANS) The Iran government on Wednesday approved a proposal to change the name of the country's currency unit from rial to toman, media reported.

One toman equals 10 rials and one dollar is worth about 3,900 tomans in Iran's unofficial market currently, Xinhua news agency reported.

​London, Dec 8 (IANS) Repeatedly hearing fake events of the past such as taking a hot air balloon ride, playing a prank on a teacher or creating havoc at a family wedding during childhood, may push people into imagining them and believing that which never happened, researchers say.

In a study conducted on false memories, more than 400 participants were suggested fictitious autobiographical events, nearly 50 per cent believed, to some degree, that they had experienced those events.

Thirty per cent of participants appeared to 'remember' the event, they accepted the suggested event, elaborated on how the event occurred, and even described images of what the event was like.

Another 23 per cent showed signs that they accepted the suggested event to some degree and believed it really happened.

It can be very difficult to determine when a person is recollecting actual past events, as opposed to false memories, even in a controlled research environment and more so in real life situations, said Kimberley Wade from University of Warwick in Britain. 

The study may have significance in many areas such as raising questions around the authenticity of memories used in forensic investigations, court rooms and therapy treatments.

However, misinformation in the news can create incorrect collective memories that can affect behaviour and attitudes of society, the researchers explained.

"The finding that a large portion of people are prone to developing false beliefs is important. We know from other research that distorted beliefs can influence people's behaviours, intentions and attitudes," Wade said.

The study was published in the journal Memory.

New York, Dec 8 (IANS) A team of University of Illinois researchers has discovered the existence of hot atomic hydrogen (H) atoms in an upper layer of Earth's atmosphere known as thermosphere.

This finding significantly changes current understanding of the H distribution and its interaction with other atmospheric constituents.

Because H atoms are very light, they can easily overcome a planet's gravitational force and permanently escape into interplanetary space.

The ongoing atmospheric escape of H atoms is one reason why Earth's sister planet, Mars, has lost the majority of its water.

In addition, H atoms play a critical role in the physics governing the Earth's upper atmosphere and also serve as an important shield for satellites in low-earth orbit against the harsh space environment.

"Hot H atoms had been theorized to exist at very high altitudes, above several thousand km, but our discovery that they exist as low as 250 km was truly surprising," said Lara Waldrop, assistant professor of electrical and computer engineering and principle investigator of the project.

The result suggests that current atmospheric models are missing some key physics that impacts many different studies, ranging from atmospheric escape to the thermal structure of the upper atmosphere.

The results also show that the presence of such hot H atoms in the thermosphere significantly affects the distribution of the H atoms throughout the entire atmosphere.

The origin of such hot H atoms, previously thought not to be able to exist in the thermosphere, is still a mystery.

"We know that there must be a source of hot H atoms, either in the local thermosphere or in more distant layers of the atmosphere, but we do not have a solid answer yet," said Waldrop in a paper published in the journal Nature Communications.

​New York, Dec 8 (IANS) Want to live longer? Try to maintain an optimistic outlook towards life -- a general expectation that good things will happen.

In the study, the researchers have found that women who were optimistic had a significantly reduced risk of dying from several major causes of death -- including cancer, heart disease, stroke, respiratory disease and infection, compared with women who were less optimistic.

"While most medical and public health efforts today focus on reducing risk factors for diseases, evidence has been mounting that enhancing psychological resilience may also make a difference," said Eric Kim, research student at Harvard T.H. Chan School of Public Health, US.

"Our new findings suggest that we should make efforts to boost optimism, which has been shown to be associated with healthier behaviours and healthier ways of coping with life challenges," Kim added.

The study also found that healthy behaviours only partially explain the link between optimism and reduced mortality risk. 

One other possibility is that higher optimism directly impacts our biological systems, Kim said.

For the study, the team analysed 70,000 women's levels of optimism and other factors that might play a role in how optimism may affect mortality risk, such as race, high blood pressure, diet and physical activity.

The results showed that most optimistic women had a nearly 30 per cent lower risk of dying from any of the diseases analysed in the study compared with the least optimistic women.

Previous studies have shown that optimism can be altered with relatively uncomplicated and low-cost interventions, even something as simple as having people write down and think about the best possible outcomes for various areas of their lives, such as careers or friendships, the researchers said, adding that encouraging the use of such interventions could be an innovative way to enhance health in the future.

The study appeared online in the American Journal of Epidemiology.

​New York, Dec 8 (IANS) Not just pizzas or groceries, drones can one day transport blood for transfusion to hospitals in rural areas -- while keeping it safe and intact -- in less time.

In what is believed to be the first proof-of-concept study of its kind, researchers from Johns Hopkins University have determined that large bags of blood products, such as those transfused into patients every day, can maintain temperature and cellular integrity while transported by drones.

Remotely-piloted drones are an effective, safe and timely way to quickly get blood products to remote accident or natural catastrophe sites, or other time-sensitive destinations.

"For rural areas that lack access to nearby clinics, or that may lack the infrastructure for collecting blood products or transporting them on their own, drones can provide that access," says Timothy Amukele, assistant professor of pathology and the paper's first author.

The new study examined the effects of drone transportation on larger amounts of blood products used for transfusion, which have significantly more complex handling, transport and storage requirements compared to blood samples for laboratory testing.

The team purchased six units of red blood cells, six units of platelets and six units of unthawed plasma from the American Red Cross, and then packed the units into a 5-quart cooler two to three units at a time.

The cooler was then attached to a commercial S900-model drone.

This particular drone model comes equipped with a camera mount, which the team removed and replaced with the cooler.

For each test, the drone was flown by remote control a distance of approximately 13 to 20 km while 328 feet above ground. This flight took up to 26.5 minutes.

The team designed the test to maintain temperature for the red blood cells, platelets and plasma units. They used wet ice, pre-calibrated thermal packs and dry ice for each type of blood product, respectively.

Following flight, all samples were transported to The Johns Hopkins Hospital where the team used the institution's laboratories to check for any damage.

The team plans larger studies in the US and overseas and hopes to test methods of active cooling, such as programming a cooler to maintain a specific temperature.

The findings are forthcoming in the journal Transfusion.

New York, Dec 8 (IANS) Saturn's moons may be younger than previously thought, says a study based on freshly-harvested data from NASA's Cassini mission.

"All of these Cassini mission measurements are changing our view of the Saturnian system, as it turns our old theories upside down," said Radwan Tajeddine from Cornell University in the US.

Tajeddine is a member of the European-based Encelade scientific team that pored over the Cassini data.

The Encelade team provided two key measurements in the research -- the rigidity of the tidal bulge, or the Love number - named for Augustus E.H. Love, a famed British mathematician who studied elasticity - and the dissipation factor, which controls the speed at which moons move away.

While Saturn is mostly a gigantic shroud of liquid hydrogen and liquid helium, it contains a rocky core -- about 18 times the size of Earth, which responds to tidal forces from all of Saturn's major moons by bulging. 

The forces of the bulging core, in turn, push the moons slightly away.

The team detected and examined the orbits of four tiny moons associated with the larger moons Tethys (Telesto and Calypso) and Dione (Helene and Polydeuces). 

While these tiny moons do not affect the tidal forces on Saturn, their orbits are disturbed by Saturn's core tidal bulges.

"By monitoring these disturbances, we managed to obtain the first measurement of Saturn's Love number and distinguish it from the planet's dissipation factor," Tajeddine said. 

"The moons are migrating away much faster than expected," Tajeddine said.

If Saturn moons actually formed 4.5 billion years ago, as currently believed, their current distances from the home planet should be greater, Tajeddine explained.

Thus, this new research -- published in the astronomy journal Icarus -- suggests, the moons are younger than 4.5 billion years, favouring a theory that the moons formed from Saturn's rings.

"What we believe about Saturn's moons history might still change in the coming years with the finale of the Cassini mission," lead researcher Valery Lainey of the Paris Observatory said.

"The more we learn about Saturn, the more we learn about exoplanets," Lainey noted.