Amid the shortage of medical oxygen for treating COVID-19 patients, the IIT-Bombay has come up with an ingenious solution to help address the issue by converting a nitrogen unit into an oxygen generating unit, the institute said on Thursday.

The pilot project, which has been tested successfully, relies on a simple technological intervention of converting a Pressure Swing Adsorption nitrogen unit into a PSA oxygen unit, according to an official statement.

It claimed that initial tests conducted at the Indian Institute of Technology (IIT) Bombay have shown “promising results”.

The oxygen production could be achieved at “3.5 atm pressure with a purity level of 93% to 96%”, the statement said.

This gaseous oxygen can be utilised for COVID-19- related needs across the existing hospitals and upcoming COVID-19-specific facilities by providing a continuous supply of oxygen, it said.

“It [conversion of nitrogen unit into an oxygen unit] has been done by fine-tuning the existing nitrogen plant setup and changing the molecular sieves from Carbon to Zeolite,” the statement said quoting Prof. Milind Atrey, dean (R&D), IITB, who led the project.

Mr. Atrey said such nitrogen plants, which take air from the atmosphere as raw material, are available in various industrial plants across India.

“Therefore, each of them could potentially be converted into an oxygen generator, thus helping us tide over the current public health emergency,” he said.

The pilot project is a collaborative effort among IIT-Bombay, Tata Consulting Engineers and Spantech Engineers, Mumbai, who deal with the PSA nitrogen and oxygen plant production, the statement said.

To undertake this study on an urgent basis, an MoU was signed among IIT-Bombay, Tata Consulting Engineers and Spantech Engineers to finalise a standard operating procedure (SOP) that may be leveraged across the country, it said.

IIT-Bombay Director Prof. Subhasis Chaudhuri congratulated all the involved parties and said such partnership between the academia and industry is “highly” desirable and essential for the growth and success of the nation, it added.

China launched an unmanned module on Thursday containing what will become living quarters for three crew on a permanent space station that it plans to complete by the end of 2022, state media reported.

The module, named "Tianhe", or "Harmony of the Heavens", was launched on the Long March 5B, China's largest carrier rocket, at 11:23 a.m. (0323 GMT) from the Wenchang Space Launch Centre on the southern island of Hainan.

Tianhe is one of three main components of what would be China's first self-developed space station, rivalling the only other station in service - the International Space Station (ISS).

The ISS is backed by the United States, Russia, Europe, Japan and Canada. China was barred from participating by the United States.

"(Tianhe) is an important pilot project in the building of a powerful nation in both technology and in space," state media quoted President Xi Jinping as saying in a congratulatory speech.

Tianhe forms the main living quarters for three crew members in the Chinese space station, which will have a life span of at least 10 years.

The Tianhe launch was the first of 11 missions needed to complete the space station, which will orbit Earth at an altitude of 340 to 450 km (211-280 miles).

In the later missions, China will launch the two other core modules, four manned spacecraft and four cargo spacecraft.

Work on the space station programme began a decade ago with the launch of a space lab Tiangong-1 in 2011, and later, Tiangong-2 in 2016.

Both helped China test the programme's space rendezvous and docking capabilities.

China has prioritised space exploration in recent years, with the aim of becoming a major space power by 2030. By 2045, it hopes to establish a programme operating thousands of space flights a year and carrying tens of thousands of tonnes of cargo and passengers.

Apollo 11 astronaut Michael Collins, who piloted the ship from which Neil Armstrong and Buzz Aldrin left to make their historic first steps on the moon in 1969, died on Wednesday of cancer, his family said. He was 90.

Mr. Collins was part of the three-man Apollo 11 crew that effectively ended the space race between the United States and Russia and fulfilled President John F Kennedy's challenge to reach the moon by the end of the 1960s.

Though he travelled some 238,000 miles to the moon and came within 69 miles, Mr. Collins never set foot on the lunar surface like his crewmates Mr. Aldrin and Mr. Armstrong, who died in 2012. None of the men flew in space after the Apollo 11 mission.

“It's human nature to stretch, to go, to see, to understand,” Mr. Collins said on the 10th anniversary of the moon landing in 1979.

“Exploration is not a choice really — it's an imperative, and it's simply a matter of timing as to when the option is exercised.” In a statement, acting NASA administrator Steve Jurczyk said: “Whether his work was behind the scenes or on full view, his legacy will always be as one of the leaders who took America's first steps into the cosmos.” Mr. Collins spent the eight-day mission piloting the command module. While Mr. Armstrong and Mr. Aldrin descended to the moon's surface in the lunar lander, Eagle, Collins remained alone in the command module, Columbia.

“I guess you're about the only person around that doesn't have TV coverage of the scene,” Mission Control radioed Mr. Collins after the landing.

“That's all right. I don't mind a bit,” he responded.

Mr. Collins was alone for nearly 28 hours before Mr. Armstrong and Mr. Aldrin finished their tasks on the moon's surface and lifted off in the lunar lander.

Mr. Collins was responsible for re-docking the two spacecraft before the men could begin heading back to Earth. Had something gone wrong and Mr. Aldrin and Mr. Armstrong been stuck on the moon's surface — a real fear — Mr. Collins would have returned to Earth alone.

Though he was frequently asked if he regretted not landing on the moon, that was never an option for Mr. Collins, at least not on Apollo 11.

Mr. Collins' specialty was as a command module pilot, a job he compared to being the base-camp operator on a mountain climbing expedition. As a result, it meant he wasn't considered to take part in the July 20, 1969, landing.

“I know that I would be a liar or a fool if I said that I have the best of the three Apollo 11 seats, but I can say with truth and equanimity that I am perfectly satisfied with the one I have,” he wrote in his 1974 autobiography, “Carrying the Fire.” “This venture has been structured for three men, and I consider my third to be as necessary as either of the other two.” Mr. Collins was born in Rome on Halloween 1930. His parents were Virginia Collins and U.S. Army Maj. Gen. James L. Collins. After graduating from the U.S. Military Academy in 1952, a year behind Aldrin, Collins joined the Air Force, where he became a fighter pilot and test pilot.

John Glenn's 1962 flight making him the first American to orbit the Earth persuaded Mr. Collins to apply to NASA. He was accepted on his second try, in 1963, as part of the third group of astronauts selected. Mr. Collins' first mission was 1966's Gemini 10, one of the two-man missions made in preparation for flights to the moon.

Along with John Young, Collins practiced maneuvers necessary for a moon landing and performed a spacewalk during the three-day mission. During the spacewalk, he famously lost a camera, which is frequently cited as one of the items of “space junk” orbiting Earth.

On January 9, 1969, NASA announced that Mr. Collins, Mr. Armstrong and Mr. Aldrin would be on the crew of Apollo 11, the United States' first moon landing attempt.

Of his fellow Apollo 11 astronauts, Mr. Collins said they were: “Smart as hell, both of them, competent and experienced, each in his own way.” Still, Mr. Collins called the group “amiable strangers” because the trio never developed as intense a bond as other crews.

Of the three, Collins was the acknowledged jokester. Mr. Aldrin called him the “easygoing guy who brought levity into things.” In summarising Mr. Kennedy's famous challenge to go to the moon, for example, Mr. Collins later said: “It was beautiful in its simplicity. Do what? Moon. When? End of decade.” The Apollo 11 crew trained for just six months before launching on July 16, 1969, from Florida's Cape Canaveral. The mission insignia — an eagle landing on the moon with an olive branch in its talons — was largely Collins' creation.

Mr. Collins said one of the things that struck him most was the way the Earth looked from space — peaceful and serene but also delicate.

“As I look back on Apollo 11, I more and more am attracted to my recollection, not of the moon, but of the Earth. Tiny, little Earth in its little black velvet background,” Mr. Collins said while marking the mission's 50th anniversary in 2019.

In contrast, he said the moon seemed almost hostile. In fact, it was considered so hostile that on their return, Collins, Armstrong and Aldrin all spent several days in a quarantine trailer. They received visitors, including President Richard Nixon, staring through a window.

When the group was finally deemed safe, they went on a world tour, visiting 25 countries in just over five weeks.

Mr. Collins often remarked that he was surprised that everywhere they went people didn't say “Well, you Americans finally did it.” Instead, they said, “Well, we finally did it,” meaning “we” humans.

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Seafloor study

Published in Nature Communications

The Red Sea is no longer a baby ocean. It is a young adult with a structure similar to the young southern Atlantic some 120 million years ago, notes a new study. By studying high-resolution seafloor maps and also investigating the chemical makeup of rock samples, the international team was able to arrive at this conclusion.

Tough cage-suit

Published in Nature Materials

It's time to lose your leather racing suits and buy an advanced version made of zeolite. Researchers at the University of Birmingham have developed a new material using zeolitic imidazolate frameworks which can be used to develop shock and impact resistant clothing for soldiers, athletes, and motorists.

Fungal friend

Published in PNAS

Meet Parascedosporium putredinis, a fungus that has given the world a new enzyme. Researchers noted that the enzyme can act as a catalyst to break down lignocellulose. "We believe this discovery is important as there is much interest in using lignocellulose as a renewable and sustainable resource for the production of liquid fuels and chemicals,” says lead author Neil Bruce in a release.

HIV's favourite targets

Published in Cell Reports

It is well known that HIV attacks and destroys our CD4+ T cells. "CD4+ T cells orchestrate the immune response against all kinds of pathogens, so you can't just eliminate them to prevent HIV infections," explains lead author Nadia Roan in a release. "But if you can find the more specific subsets of CD4+ T cells that are highly susceptible to HIV infection, you may be able to specifically target those cells without detrimental side effects." Using new technologies the team has now established a detailed atlas of the CD4+ T cells, which can help scientists determine whether some subsets are more susceptible to infection than others.

Plastic to fuel

Published in Current Biology

Researchers from the University of Delaware have developed a new direct method to convert single-use plastic waste to molecules that can be used for jet fuels. “The process can be tuned to convert different common plastic wastes, including low- and high-density polyethylene, polypropylene, polystyrene, everyday polyethylene bottles and bags, and composite plastics to desirable fuels and light lubricants,” adds the paper.

One in four people experience mild, short lived systemic side effects after receiving the COVID-19 preventive by Oxford-AstraZeneca (ChAdOx1 nCoV-19) vaccine — known as Covishield in India — with headache, fatigue and tenderness the most common symptoms, according to a study published in the Lancet Infectious Diseases journal.

The researchers from King's College London in the U.K. also found that most systemic side effects — meaning side effects excluding where the injection took place — peaked within the first 24 hours following vaccination and usually lasted 1-2 days.

Systemic effects included headache, fatigue, chills and shiver, diarrhoea, fever, arthralgia, myalgia, and nausea. Local side effects — meaning side effects where the injection took place in the arm — included pain at the site of injection, swelling, tenderness, redness, itch, warmth and swollen armpit glands.

The analysis of data from the ZOE COVID Symptom Study app found much fewer side effects in the general population with both the Pfizer and AstraZeneca vaccines than reported in trials.

"The data should reassure many people that in the real world, after effects of the vaccine are usually mild and short-lived, especially in the over 50's who are most at risk of the infection," said Professor Tim Spector, lead scientist on the ZOE COVID Symptom Study app and Professor at King's College London.

The data comes from 627,383 users of the ZOE COVID Symptom Study app who self-reported systemic and local effects within eight days of receiving one or two doses of the Pfizer vaccine or one dose of the AstraZeneca vaccine between December 8 and March 10.

The study also found that side effects were more common among people under 55 years of age and among women. Participants who had a confirmed case of prior COVID-19 were three times more likely to have side effects that affect the whole body after receiving doses of the Pfizer vaccine than those without known infection. Those with a confirmed case of prior COVID-19 number were almost twice more likely to have side effects that affect the whole body after the first dose of the AstraZeneca vaccine.

The researchers noted that in Phase III clinical trials of the Pfizer vaccine, the most common side effects were pain at the injection site (71-83%), fatigue (34-47%) and headache (25-42%). However, the real-world analysis found less than 30% of users complained of injection site pain and less than 10% of fatigue and headache after the first dose, they said. Similarly, in Phase III trials for the AstraZeneca vaccine, systemic side effects were found in 88% of younger participants (18-55 years) after the first dose but the study found a significantly lower rate of 46.2% after the first dose.

"Our results support the after effects safety of both vaccines with fewer side effects in the general population than reported in the Pfizer and AstraZeneca experimental trials and should help allay safety concerns of people willing to get vaccinated," Spector added

The study also reports a significant decrease of infection rates from 12 to 21 days after the first dose of the Pfizer (58% reduction) and AstraZeneca (39% reduction) vaccines compared to a control group. The drop in infection at least 21 days after the first dose for Pfizer is 69% and for AstraZeneca 60%, according to the study.

A study has found that people who have been vaccinated with Covaxin have protection against the double mutant (B.1.617) variant first found in India. A preprint of the study carried out by ICMR and Bharat Biotech researchers has been posted in biorXiv. Preprints are yet to be peer-reviewed and published in medical journals.

So far, 21 countries have detected the B.1.617 variant. Of those, the majority of cases has been reported from India.

The researchers used the sera collected from 28 people who had participated in the Covaxin phase-2 trial. They also collected sera samples from 17 people who were infected with older strains of SARS-CoV-2 virus and had recovered.

“The study found that the neutralising capacity against the double mutant (B.1.617) variant was found to be good in both groups — people who have received the vaccine and those who have recovered from COVID-19,” says Dr. Samiran Panda, a senior scientist at ICMR and one of the co-authors of the preprint.

“Compared with people who have recovered from COVID-19, the ability of the sera of vaccinated people to neutralise the B.1.617 variant was found to be two-fold less.”

An earlier study had found that Covaxin neutralises the B.1.1.7 variant first found in the U.K.

“The assurance of neutralisation of B.1.617 variant with sera of Covaxin vaccinees and recovered COVID-19 sera will provide the much-needed boost for the COVID-19 vaccination programme in India,” the authors write.

Speaking to reporters during a conference call on April 27, Dr. Antony Fauci, Director of the National Institute of Allergy and Infectious Diseases (NIAID), said: “Despite the real difficulty that we’re seeing in India, vaccination could be a very important antidote against this [variant].”

The B.1.617 variant has two mutations — E484Q and L425R — of concern. These mutations are found in the receptor-binding domain of the spike protein. Though how the two mutations behave individually is well known, the combined effect of these mutations when present together is not known. “Further studies are needed to understand the transmissibility and infectivity of the B.1.617 variant,” the authors write.

The World Health Organization said Tuesday that a variant of COVID-19 feared to be contributing to a surge in coronavirus cases in India has been found in over a dozen countries.

The U.N. health agency said the B.1.617 variant of COVID-19 first found in India had as of Tuesday been detected in over 1,200 sequences uploaded to the GISAID open-access database "from at least 17 countries".

"Most sequences were uploaded from India, the United Kingdom, USA and Singapore," the WHO said in its weekly epidemiological update on the pandemic.

The WHO recently listed B.1.617 — which counts several sub-lineages with slightly different mutations and characteristics — as a "variant of interest".

But so far it has stopped short of declaring it a "variant of concern".

That label would indicate that it is more dangerous that the original version of the virus by for instance being more transmissible, deadly or able to dodge vaccine protections.

India is facing surging new cases and deaths in the pandemic, and fears are rising that the variant could be contributing to the unfolding catastrophe.

The explosion in infections in India — 350,000 new cases were recorded there on Tuesday alone — has driven a surge in global cases to 147.7 million.

The virus has now killed more than 3.1 million people worldwide.

The WHO acknowledged that its preliminary modelling based on sequences submitted to GISAID indicates "that B.1.617 has a higher growth rate than other circulating variants in India, suggesting potential increased transmissibility".

It stressed that other variants circulating at the same time were also showing increased transmissibility, and that the combination "may be playing a role in the current resurgence in this country."

"Indeed, studies have highlighted that the spread of the second wave has been much faster than the first," the WHO said.

It highlighted though that "other drivers" could be contributing to the surge, including lax adherence to public health measures as well as mass gatherings.

"Further investigation is needed to understand the relative contribution of these factors," it said.

The UN agency also stressed that "further robust studies" into the characteristics of B.1.617 and other variants, including impacts on transmissibility, severity and the risk of reinfection, were "urgently needed".

One in seven pregnancies worldwide ends in miscarriage, and eleven percent of women endure a failed pregnancy at least once in their lifetime, experts said Tuesday.

Some 23 million miscarriages occur every year, according to data pieced together from around the globe by an international team of 31 researchers.

But the actual tally is sure to be "substantially higher" due to underreporting, they said in a trio of studies published in The Lancet.

Two percent of women — one in 50 — have experienced two miscarriages, while less that one percent have been through three or more.

Levels of care for women suffering miscarriage is highly uneven across countries, and even within many wealthy nations, the data showed.

"A new system is needed to ensure miscarriages are better recognised and women are given the physical and mental health care they need," the researchers said in a statement.

Misconceptions about miscarriage are widespread. Many women believe they occur only rarely, for example, or that they can be caused by lifting heavy objects or previous contraceptive use.

They may also think that there's no effective treatments to prevent a miscarriage, especially in women at high risk.

Such misconceptions can be damaging, leaving women and their partners feeling at fault and discouraging them from seeking treatment and support, the authors note.

Miscarriage can also lead to isolation, since many women might not tell their family, close friends, or even their partner about the loss of a pregnancy.

"Silence around miscarriage remains not only for women who experience it, but also among health care providers, policymakers and research funders," said co-lead author Siobhan Quenby, a professor at the University of Warwick and director of Tommy's National Centre for Miscarriage Research.

A miscarriage is widely defined as the loss of a pregnancy before 20 to 24 weeks of gestation, with the exact time period varying from country to country.

Unrecognised trauma

A review of published academic literature up to mid-May 2020 identified many causes for miscarriages, including a more advanced maternal age, previous miscarriages, and a father older than 40.

Other risk factors correlating with pregnancies that end spontaneously are being extremely under- or over-weight, smoking, alcohol consumption, persistent stress, working night shifts, and constant exposure to air pollution or pesticides.

Health consequences can be severe, especially for women who experience a second or multiple miscarriages.

"Recurrent miscarriage is a devastating experience for most women, but the mental health impact is rarely acknowledged or addressed in medical care," said co-lead author Arri Coomarasamy, from the University of Birmingham. "Women can experience trauma and bereavement, which may have no obvious sign and can go unrecognised."

There is also a link with anxiety, depression and — for about 20 percent of women — post-traumatic stress disorder nine months after a miscarriage.

The authors of the three studies noted that most data comes from wealthier nations, but that the "silence around miscarriage" is found everywhere.

They recommended that national health authorities strengthen miscarriage care services, improve research in prevention, and identify women at high risk.

"For too long miscarriage has been minimised and often dismissed," The Lancet said in an companion editorial. "The lack of medical progress should be shocking — instead, there is pervasive acceptance."

"The era of telling women to 'just try again' is over," The Lancet said.

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NASA's mini helicopter Ingenuity on Sunday successfully completed its third flight on Mars, moving farther and faster than ever before, with a peak speed of 6.6 feet per second.

After two initial flights during which the craft hovered above the Red Planet's surface, the helicopter on this third flight covered 64 feet (50 meters) of distance, reaching the speed of 6.6 feet per second (two meters per second), or four miles per hour in this latest flight.

"Today's flight was what we planned for, and yet it was nothing short of amazing," said Dave Lavery, the Ingenuity project's program executive.

The Perseverance rover, which carried the four-pound (1.8 kilograms) rotorcraft to Mars, filmed the 80-second third flight. NASA said Sunday that video clips would be sent to Earth in the coming days.

The lateral flight was a test for the helicopter's autonomous navigation system, which completes the route according to information received beforehand.

"If Ingenuity flies too fast, the flight algorithm can't track surface features," NASA explained in a statement about the flight.

Ingenuity's flights are challenging because of conditions vastly different from Earth's -- foremost among them a rarefied atmosphere that has less than one percent the density of our own.

This means that Ingenuity's rotors, which span four feet, have to spin at 2,400 revolutions per minute to achieve lift -- about five times more than a helicopter on Earth.

NASA announced it is now preparing for a fourth flight. Each flight is planned to be of increasing difficulty in order to push Ingenuity to its limits.

The Ingenuity experiment will end in one month in order to let Perseverance return to its main task: searching for signs of past microbial life on Mars.

Scientists have discovered what may be the smallest-known black hole in the Milky Way galaxy and the closest to our solar system — an object so curious that they nicknamed it 'the Unicorn.'

The researchers said the black hole is roughly three times the mass of our sun, testing the lower limits of size for these extraordinarily dense objects that possess gravitational pulls so strong not even light can escape. A luminous star called a red giant orbits with the black hole in a so-called binary star system named V723 Mon.

The black hole is located about 1,500 light years — the distance light travels in a year, 9.5 trillion km — from Earth. While it may be the closest one to us, it is still far away. By way of comparison, the closest star to our solar system, Proxima Centauri, is 4 light years away.

Black holes like this one form when massive stars die and their cores collapse.

"We nicknamed this black hole 'the Unicorn' partly because V723 Mon is in the Monoceros constellation — which translates to unicorn — and partly because it is a very unique system" in terms of the black hole's mass and relative closeness to Earth, said Ohio State University astronomy doctoral student Tharindu Jayasinghe, lead author of the study published this week in the journal Monthly Notices of the Royal Astronomical Society.

There are three categories of black holes:

1. The smallest, like 'the Unicorn,' are so-called stellar mass black holes formed by the gravitational collapse of a single star.
2. There are gargantuan 'supermassive' black holes like the one at our galaxy's center, 26,000 light years from Earth, which is four million times the sun's mass.
3. A few intermediate-mass black holes also have been found with masses somewhere in between.

"It is clear that nature makes black holes of a wide range of masses. But a three-solar-mass black hole is a big surprise. There are no very good models for how to make such a black hole, but I am sure people will work on that more now," said Ohio State University astronomy professor and study co-author Kris Stanek.

'The Unicorn' falls into what the researchers called a "mass gap" between the largest-known neutron stars - objects similarly formed by a large star's collapse - at around 2.2 times the mass of our sun and what previously had been considered the smallest black holes at around five times the sun's mass.

"'The unicorn' is truly one of the smallest black holes possible," Jayasinghe said.

Its strong gravity alters the shape of its companion star in a phenomenon known as tidal distortion, making it elongated rather than spherical and causing its light to change as it moves along its orbital path. It was these effects on the companion star, observed using Earth-based and orbiting telescopes, that indicated the black hole's presence.

"Black holes are electromagnetically dark, and so they are difficult to find," Jayasinghe said.

Unlike some other black holes orbiting with a star, this one was not observed to be drawing material from its companion, which is 173 times more luminous than our sun. The only smaller potential black hole is one with a mass 2.6 times that of our sun that was spotted in another galaxy, Jayasinghe said.

China’s first Mars rover will be named Zhurong after a traditional fire god, the government announced Saturday.

The rover is aboard the Tianwen-1 probe that arrived in Mars orbit on February 24 and is due to land in May to look for evidence of life.

It is part of Chinese space plans that include launching a crewed orbital station and landing a human on the moon. China in 2019 became the first country to land a space probe on the little-explored far side of the moon and in December returned lunar rocks to Earth for the first time since the 1970s.

The rover’s title fits with the Chinese name for Mars — “Huo Xing,” or fire star, the China National Space Administration said.

The name “signifies igniting the flame of China’s planetary exploration,” a deputy CNSA administrator, Wu Yanhua, was cited by the official Xinhua News Agency as saying.

The top candidate for the landing site is Utopia Planitia, a rock-strewn plain where the U.S. lander Viking 2 touched down in 1976.

CNSA says Tianwen-1's goals include analysing and mapping the Martian surface and geology, looking for water ice and studying the climate and surface environment.

China would become the third country after the former Soviet Union and the United States to put a robot rover on Mars.

Researchers have discovered a series of creativity-linked genes that may have given Homo sapiens a significant edge over Neanderthals, enabling them to avoid extinction.

The findings suggest that these genes played "a fundamental role in the evolution of creativity, self-awareness and cooperative behaviour," the multinational research team wrote Wednesday in the Nature journal Molecular Psychiatry.

Such genes were like "a secret weapon" that gave modern humans "a significant advantage over now-extinct hominids by fostering greater resilience to ageing, injury, and disease, they wrote.

Led by Granada University in Spain, the experts identified 267 genes unique to humans, and through genetic markers, genetic expression data and AI-related MRI techniques, found they were related to creativity.

"The scientists were able to identify the regions of the brain in which those genes (and those with which they interacted) were overexpressed," they wrote. "These regions are involved in human self-awareness and creativity, and include the regions that are strongly associated with human well-being and that appeared relatively recently."

Previously, the same team had identified a pool of 972 genes organised into three brain networks, the oldest — which relates to learning habits, social attachment and conflict resolution — dating back 40 million years. The second network — which relates to intentional self-control — emerged 2 million years ago, while the newest, governing creative self-awareness, only emerged 100,000 years ago.

"Thanks to these genes, Homo sapiens enjoyed greater physical fitness than now-extinct hominids, providing them with a superior level of resilience to ageing, injury, and disease," they wrote.

"Physical fitness, or resilience, is intrinsic to the definition of creativity," said the study's lead author Igor Zwir.

The finding offers fresh insight into the mystery of why Homo sapiens outlived the Neanderthals and other species.

The authors said creativity may have encouraged cooperation between individuals which would have set the stage for technological innovation, behavioural flexibility and openness to exploration, enabling them to spread out more successfully than their predecessors.

Researchers from Purdue University in the U.S. have developed an ‘ultra-white’ paint, which when painted onto buildings, can reflect the sunlight falling on them and lower the temperature indoors by 4.5 degrees Celsius than the surroundings. They say this can alleviate global warming on two counts; by reducing carbon emissions from air conditioners, and driving the sun’s incoming heat away to outer space – a principle called radiative cooling.

The able to achieve this by adding Barium sulfate(BaSO4) to acrylic paint, imparting a reflectance of 98.1%. This marked an improvement over the team’s earlier work last year that made use of Calcium carbonate(CaCO3) as a filler material to produce a paint that boasted 95.5% reflectance. To lend context, heat-reflective commercial white paints in the market possess reflectance ranging from 80 - 91%. But they are unable to maintain a temperature consistently lower than the surroundings throughout the day.

Speaking to The Hindu over email, Xiulin Ruan, who headed the team, says “Our previous CaCO3 paint could consistently cool 1.7 degrees Celsius below the ambient temperature. The new BaSO4 paint can cool 4.5 degrees Celsius below the ambient surroundings.” The findings were published recently in the journal ACS Applied Materials & Interfaces.

In BaSO4, they found a compound with low heat absorption and high sky emissivity. The compound, characterised by a high electron band-gap, requires greater energy for an electron to jump from the valence band to the conduction band and start conducting heat. This ensures there is minimal absorption of the heat falling on the surface.

“The previous paint absorbs 4.5% sunlight while the new paint only absorbs 1.9%, representing a 58% reduction of heat gain from the sun. For a one-story house with a 100m2 roof area, this represents an increase of 2.6 kW cooling power for the new paint,” Dr. Ruan says.

By adopting a relatively high volume concentration of 60%, and employing particles of varying sizes rather than a uniform one, the BaSO4-acrylic paint is able to reflect sunlight at a wavelength suitable enough to pass through the atmosphere during the day and take it to deep space — a principle called sky emissivity. The paint functioning in this manner can offer an average cooling power of 117 W/m2.

“We did some simple analysis...and found out that you could save up to 70% air conditioning cost in the summer,” Dr. Ruan says.

But there are apprehensions that the gains made this way could be offset by heating requirements during winter. When asked about this, Dr. Ruan says: “Right now, this paint will be most suitable for hot climates where air conditioning in the summer is the primary need rather than heating in the winter. On certain days, you might not need to turn on the air conditioner while on other very hot days, you need to turn on air conditioner, but the paint can help offset some cooling demand. “

“However, it is possible to develop dynamic coatings to switch properties between summer and winter hence used for all climates, but it will take some time,” he adds.

Spiders are fascinating creatures. Master builders who expertly weave strands of silk into intricate webs, spiders use these both as their home and their hunting grounds. Human beings have been enthralled by the spider’s ways and there have been many who have wished to enter the spider’s world to learn more about web construction and arachnid behaviour.

Notes from the web

In April 2021, a group of researchers from Massachusetts Institute of Technology (MIT) along with collaborators at Studio Tomas Saraceno reported a way of translating the structure of spider’s web into music. As spiders live in an environment of vibrating strings with different frequencies, which they use to sense the world around them, researchers decided to extract these rhythms of non-human origin and convert them to music.

In order to achieve their objective, a laser was used to capture the spider web. The 2D cross-sections thus obtained were then reconstructed into a 3D web network using the aid of computer algorithms.

Next, different frequencies of sound were assigned to each strand of a web, thereby creating notes. These were combined based on the web’s patterns to create melodies. By creating a harp-like instrument, the researchers then played the spider web music in a number of live performances around the world.

3D printing

Apart from the wow factor that such a research provides and the fact that it could act as musical inspiration as well, researchers have identified a number of other uses that might come in handy. After gaining insights into how spiders build their webs, the step-by-step knowledge could be used in constructing 3D printers that mimic these spiders and hence might be able to build complex electronic circuits.

Additionally, these experiments showed that an algorithm was able to correctly classify spider sounds into different activities, even though they sounded similar to human ears. This means that the time when human beings learn how to communicate with spiders in their own language may not be that far away!

With the daily infections accelerating at a blazing speed to reach 3,45,103 on April 23, and the daily deaths stubbornly remaining above 2,000 and rising since April 20, the second wave is growing at an alarming rate resulting in health-care facilities bursting at the seams. The second wave is expected to peak in May. Bhramar Mukherjee, Professor of Epidemiology at University of Michigan in an email says there will be 8–10 lakhs cases a day in mid-May when it peaks, and 4,500 deaths around May 23. Edited excerpts:

Since April 1, the number of daily cases has been accelerating at a rapid speed. Can it be any reason other than more infectious variants?

We have to be cautious here. Causality can sometimes be established by elimination of alternative explanations. Let us try that argument here.

We all agree that it is not a single factor but a confluence of different factors all coinciding to create the perfect transmission inferno in India. Lack of covid-appropriate behaviour at a time when the country was fully reopening, massive rallies, religious gatherings, cricket matches, use of public transportations, all were taking place largely without proper face covering, throwing caution to the wind. Indoor facilities with air-conditionings like malls, theatres, restaurants were buzzing with people.

We were complacent with a false sense of security, thinking we have conquered COVID-19. Instead of anticipating the silent footsteps of this insidious virus, we let it run wild without any surveillance. Even when we saw the uptick in mid-February, we were dismissive and continued with data denial. The nonchalance, negligence, complacency and hubris cannot be ignored. Colossal mistakes were made by not accelerating vaccination when the virus curve was at its nadir.

Even with all of those features factored in, and allowing for a certain rate of re-infection consistent with existing literature (84% protection from past infections at seven months), the growth rate that we are seeing with cases growing by 8-folds, deaths increasing by 9-fold, and eight States having a reproduction number (R0) around 2 cannot be adequately explained without entertaining the possibility of an intrinsically more transmissible variant. We have data now from different Indian States showing that the double mutant or the UK variant have quickly become dominant strains in Maharashtra or Punjab for example. The increasing number of reports of cluster/family level infections also point to this hypothesis. However, without proper sequencing data over geography and time and proper epidemiological investigations, this evidence is still circumstantial.

Even if the rise is due to new highly transmissive variants, why are we seeing a sudden acceleration since April 1?

This is the nature of exponential growth, the virus creeps in silently and explodes astronomically. The rate parameter of the growth is startling, but the pattern is explainable. This is a feature of the last surges for example in the US and UK. During the 1918 Influenza pandemic, India saw a similar pattern.

We started imposing lockdowns only recently to slow down transmission. Before then we were having not one or two isolated superspreader events but a continuous flow of numerous superspreader events.

The reproduction number is over 2.5 in Uttar Pradesh and Bihar, and above 2 in Delhi, Rajasthan and West Bengal for a few days now. At this high reproduction number, are these States reporting the expected daily cases?

Our papers have consistently estimated underreporting factors for reporting cases nationally around 10-20. The IHME model is projecting 45 lakhs daily new infections today in India, pointing to a daily underreporting factor of about 15. This factor widely varies across States. Even with inaccurate numbers the relative trends are clear. From all I know, the reality on the ground is much starker than what the numbers show.

I would like to reiterate that suppressing the truth or having artificially deflated numbers does not help anyone. It hinders prudent policymaking, prevents estimating true healthcare needs or need for oxygen supply/ICU beds accurately. This pandemic has turned into this confusing policy pandemonium partially because the data and science have not been presented transparently to the public.

Based on the high reproduction number in these Uttar Pradesh, Bihar, West Bengal, Rajasthan, Madhya Pradesh, Gujarat for days, are we seeing the expected number of deaths now?

We have estimated death underreporting by a factor of 2-5 in the first wave. Now with the surge, the reporting infrastructure has probably eclipsed dramatically. So I expect the underreporting of deaths to be massive right now. All reports from burial grounds and crematoriums strongly suggest this possibility.

The fact is, we have a relative idea of the growth but we have no idea about the absolute numbers. I tell my students that this India modelling exercise is to teach them to adopt best statistical practices with the worst possible data. Finally, even if we believe the reported death numbers, the IHME is projecting 664,000 reported deaths by August 1 for India. Each number is a person and I am so heartbroken to see the loss of countless human lives that could have been saved, particularly when in a few months we may have copious vaccine supply.

Misclassification of COVID-19 deaths and attributing the cause of death to other comorbidities has happened to some extent in every country. The excess mortality calculations can provide a holistic evaluation of COVID-related deaths, comparing say year 2020 to historic data. For example, in the U.S. there have been 23% excess deaths than expected from March 2020-January 2, 2021 and 73% of those are attributed to COVID-19.

But in India, medical reporting of deaths and cause of deaths is already a very porous system so it is challenging to do such calculation reliably to quantify COVID-related fatalities in an indirect way. The data deficient infrastructure in India is really hurting us right now.

The seven-day average test positivity rate (TPR) nationally on April 23 was 18.5%. Delhi (30.5%), Chhattisgarh (30.1%), Maharashtra (24.6%), Madhya Pradesh (23.8%), Andhra Pradesh (22%) and West Bengal (20.4%) are reporting higher TPR than the national average. Are the daily fresh cases reported from these States in concordance with the test positivity rate?

These high levels of TPR can capture both increasing prevalence or limited testing. I think in this case it is a combination of both and impossible to unconfound one from the other. Again, I think all arrows point that cases are severely underreported.

How much should the daily tests be in these States to detect cases early and to bring down the TPR?

The testing shortfall can be estimated by setting a target TPR, if you set it at 5% say, that indicates it should be 4-5 times more than current level. You can also be clever with testing strategies by repeated testing with rapid tests instead of all RT-PCR tests to avoid testing bottleneck. India should also allow the home testing kit that we have in the U.S. now produced by Abbott which is inexpensive, easy to use and accurate. You can be clever with all of these strategies, there are so many papers now on optimal allocation of tests with limited budget. You have to innovate and be open to using new efficient tools.

Why are we seeing low TPR in Uttar Pradesh (12.5%), despite the number of tests done being less than in Maharashtra? What are the reasons for this?

You are asking me about a ratio where I neither believe the reported numerator nor the denominator. It could be that patients with obvious COVID-19 symptoms are not even being tested. Selection bias in testing can distort the numbers you get. We have worked on this issue of selective testing. I would like to add that some RT-PCR tests have a high false negative and they may not have the same accuracy to detect new variants if they are optimized for the original strain.

You had tweeted saying “Uttar Pradesh's growth in spread is alarming. Our models are failing at this high rate of growth to come up with sensible predictions”. Is the growth in spread alarming only in Uttar Pradesh?

No, not just Uttar Pradesh. Uttar Pradesh, West Bengal, Bihar and Delhi are on top of my “high alert” list. Then comes Andhra Pradesh, Rajasthan, Madhya Pradesh, Kerala, Gujarat, and Karnataka. Kerala is again starting to look worrisome. I feel West Bengal, Uttar Pradesh, Bihar and Kerala will need lockdown at some point. Odisha and Assam also have a high R0 value but the projected number of total cases is lower.

When do you think the second wave in India will peak and what will be the daily fresh cases reported at the time it peaks nationally?

All models are projecting a peak for infections in May right now. Deaths will be a lagged indicator by 7-10 days. The IHME is projecting early-May and we are projecting mid-May for infections to peak. We are projecting reported cases at 8-10 lakhs a day with 4,500 deaths, whereas the IHME predicts about 50 lakh infections (reported plus unreported) and 5,500 deaths at the peak of the two curves.

Do you expect a third wave in India? Are we anywhere close to reaching the daily vaccinations needed to avert a third wave?

Depends on how fast we vaccinate. We need to get to 10M vaccines a day (with the assumption of two dose vaccines). To vaccinate 800M adults it will then take another 5 months. If we could procure one dose vaccines like the J & J that will be best.

Very plausible that this will not be the last wave, this will not be the last variant we are seeing. We need to have an agile public health alert system to deal with this situation governed by data, science and humanity. We need to continue to build healthcare capacity, oxygen supply, ICU beds. Sequence reinfections, breakthrough infections.

Preparation and anticipation is the key to prevention. We have had a sluggish start to the vaccination. I am hoping with the new policies (like opening up to 18+ from May 1, approving multiple other vaccines with EUA) we can ramp up and have copious supplies by the summer.

Despite the increasing number of deaths seen since April 1 (from less than 500 daily deaths to over 2,000 on April 20) the case fatality rate is continuously dipping. How do you explain this?

Case fatality rate (CRF) is calculated by taking the ratio of deaths to cases. It could be that deaths have been growing but cases are growing at a faster rate, but please remember that death also is a lagged indicator. This lag is not incorporated in the current calculation. We should really calculate CFR by the number of deaths divided by the number of recovered plus deaths as we do not know what proportion of the active cases will die. A fair comparison could also be dividing today’s death by cases reported two weeks ago.

I really want to advocate to look at the absolute numbers of active cases here. It is your number of active cases that determines what proportion will need oxygen/ventilators and drives your plan for gauging the need for healthcare capacity.

In general we do see a lower overall mortality in more recent surges in the U.S. as younger people are infected who have less co-morbidities. We should really compare age-specific mortalities across two waves, not overall mortalities here.

It seems like the released data by the government does not indicate that younger people are more infected in the second wave, though it seems from the same briefing that there is enrichment in disease severity in younger age groups compared to the first wave. I would love to get individual level or age-sex stratified data to study this.

Adar Poonawalla, CEO of Serum Institute, issued a statement on April 24 to address the “ongoing public scepticism and confusion towards the pricing of Covishield”. The statement tried to address the controversy over whether the price of the vaccine at ₹600 (nearly $8) per dose for private hospitals was more than its cost when it was exported. But it did not refer to the issue of whether the vaccine would be priced differently for procurement by the Centre and the State governments.

Only a few hours before the statement, Union Health Minister Dr. Harsh Vardhan tweeted saying that the Central government’s procurement price for both COVID-19 vaccines — Covishield and Covaxin — remains at ₹150 per dose; the Health Ministry, too, tweeted a similar clarification.

These tweets contradicted what Mr. Poonawalla had claimed in an interview to CNBC-TV18 on April 21, that the price of ₹150 per dose was not applicable for any future procurement by the Central government, and that the vaccine would be sold at ₹400 both to the Central and State governments.

He said: “It is not a different price [for State and Central government supplies]. All government prices will henceforth be ₹400 for new contract. The ₹150 per dose for the Central government was for prior commitment and contracts. It ceases to exist after we supply 100 million doses to them. We will also charge ₹400 to any government, let me clarify that.”

These remarks had come in after the SII’s statement of April 21 announcing the price of the vaccine for State governments (at ₹400 per dose) and private hospitals (₹600 per dose) but which did not mention the price at which the vaccine would be sold to the Centre.

The April 24 statement, by remaining silent on the Health Minister’s clarification, has kept the question over “differential pricing” alive.

As regards the higher pricing for private hospitals, the statement said, “The initial prices were kept very low globally as it was based on advance funding given by those countries for at-risk vaccine manufacturing.”

However, while SII charged South Africa $5.25 per dose, AstraZeneca was supplying to European countries at $2.18 per dose.

Volumes matter

In the April 24 statement, Mr. Poonawalla also made the point that vaccines used in the universal immunisation programme were sold at a far lower price as the volumes were large. He cited the example of pneumococcal vaccines that are sold at a higher price in the private market, while the government is charged only one-third the cost.

Also read | Require around ₹3,000 crore to ramp up COVID-19 vaccine production: Adar Poonawalla

Mr. Poonawalla brought in the issue of the investment needed to scale-up manufacturing capacity to fight the pandemic to justify the higher costs. But what he left unsaid was that based on his demand for ₹3,000 crore to meet the cost of ramping up production capacity, the government had already agreed to advance that amount to SII, and ₹1,500 crore to Bharat Biotech.

While Mr. Poonawalla says that “only a limited portion of Serum’s volume will be sold to private hospitals at ₹600 per dose”, India is the only country that is selling the vaccine to private players.

With the Central government procuring 50% of the vaccines and supplying it to State governments for free administration to people above 45 years and when vaccinated in government facilities, States will be competing with private hospitals and with one another to procure the remaining 50% vaccines.

With the setting in of the second wave of covid-19, there is round the corner, a growth in the need for ventilators and related interventions. While hospital ICU beds do come with ventilators, makeshift ones will not be so, hence the need. Indian Institute of Science researchers have come up with several non-pharmaceutical interventions such as ICU ventilators, oxygen supply manifolds and oxygen concentrators which will each satisfy different sets of needs.

Low-cost solutions

In 2020, when the pandemic set in within India, Sushobhan Avasthi, Associate Professor with Centre for Nanoscience and Engineering and his team wanted to build low-cost ventilators. But as the project evolved, they realised that what was needed was a more sophisticated device that could sense when the patients were able to breathe on their own, and then wean them off gently so that they could become independent again. “In September we were ready with the D3 edition of smart ventilators that were good enough to be used in the ICU,” says Dr Avasthi. They teamed up with the company Vasmed with an aim to produce these ventilators for the market. “These would have cost about 1.5 lakh rupees,” says Anoop Varghese, COO of Vasmed, pegging the cost at approximately a third of the price of commercially available ones.

The group worked with Dr Justin Aryabhata Gopaldas, of the Manipal Hospital, Bangalore, to get inputs and feedback as they developed the devices. “There were many doctors involved initially, perhaps it was my familiarity with physics that helped. We discussed many things, for example, when a breath was taken what kinds of waves were formed,” says Dr Gopaldas. However, the effort did not see fruition during the first wave. Vasmed needed the pull of the market to be able to finance a complete testing and certification of the module.

No prior experience

The group then also started looking out for other interventions that would be useful in this juncture. They came up with the idea of the oxygen supply manifold, which is a system using which oxygen may be supplied to several patients from a central source and the amount of oxygen supplied may be adjusted.

“We started this project with zero experience in medical devices, let alone a critical one like a ventilator… Prof. Prosenjit Sen developed the touchscreen user interface. Prof. Saurabh Chandorkar designed the embedded system – the brain of the ventilator. Prof. Srinivasan Raghavan oversaw the development of the pneumatics. Most crucial of all was the enthusiasm of our students, specifically Harshvardhan Gupta and Ankit Rao,” says Dr Avasthi in recollection.

Sturdy concentrator

Meanwhile, in the Materials Engineering lab, efforts were on to produce an oxygen concentrator. Ambient air contains about 70% nitrogen and about 28% oxygen and other gases; the work of a concentrator is to separate the oxygen and collect air enriched with oxygen to the patient. “By August 2020 we had the third generation of the concentrator ready. It worked to concentrate more than 90% in five litres and 80% in ten litres. Not just this, it could run non-stop for months together without getting heated up,” says Praveen Ramamurthy, who led the effort. By September they had the system ready, but interest had died down.

“In the last couple of weeks, again I have been getting many mails and calls enquiring about this,” says Dr Ramamurthy.

Certification for safety

The device has the advantage that it can pump the data into the cloud, which can be shared with a doctor for monitoring use. The group is going to apply for a certification which will test for electrical and pressure safety and also biocompatibility. They expect it will take about two weeks to obtain.

Both the oxygen supply manifold and the oxygen concentrator are very much the need of the hour, the group feels, and can be manufactured easily.

Every year a stunning and colourful image of India does the rounds on Diwali, with claims that it was taken from space. In reality, the image is a composite of several satellite photos, created in 2003 by the National Oceanic and Atmospheric Administration (NOAA) to highlight population growth in the country.

So how do we know if a satellite image is fake or even if it has been used for misinformation? A new study says that there is a lot of this ‘deepfake geography’ happening in recent times and with new and more sophisticated artificial intelligence technologies available today, the problem could grow.

To the untrained eye it may be difficult to detect the differences between real and fake images, the researchers point out. To try to identify a “fake,” researchers employed many technical aspects of image processing, such as colour histograms and spatial domains.

Bo Zhao, assistant professor of geography at the University of Washington and lead author of the study said in a release that the study’s goal was not to show that geospatial data can be falsified, rather it was to learn how to detect fake images so that geographers can begin to develop the data literacy tools, similar to today’s fact-checking services, for public benefit.

India is the second-largest producer of wheat in the world, with over 30 million hectares in the country dedicated to producing this crop. But with severe groundwater depletion, the cropping intensity or the amount of land planted in the winter season may decrease by up to 20% by 2025, notes a new paper. Some of the important winter crops are wheat, barley, mustard and peas.

The international team studied India’s three main irrigation types on winter cropped areas: dug wells, tube wells, canals, and also analysed the groundwater data from the Central Ground Water Board. They found that 13% of the villages in which farmers plant a winter crop are located in critically water-depleted regions. The team writes that these villages may lose 68% of their cropped area in future if access to all groundwater irrigation is lost. The results suggest that these losses will largely occur in northwest and central India.

Alternative sources

The team then looked at canals to understand if they can be promoted as an alternative irrigation source and as an adaptation strategy to falling groundwater tables. But the results showed that “switching to canal irrigation has limited adaptation potential at the national scale. We find that even if all regions that are currently using depleted groundwater for irrigation will switch to using canal irrigation, cropping intensity may decline by 7% nationally,” notes the paper published in Science Advances.

When asked what new or additional adaptation strategies can be implemented, corresponding author Meha Jain explains: “We can conjecture based on other literature and say that adoption of water-saving technologies like a sprinkler, drip irrigation and maybe switching to less water-intensive crops may help use the limited groundwater resources more effectively,” She is from the School for Environment and Sustainability at the University of Michigan.

Her team is now trying to understand how groundwater depletion has already reduced yields and cropped areas in India over the last 20 years, and also how climate change may affect the future availability of groundwater resources.

Unsuited soils

Balwinder Singh from the International Maize and Wheat Improvement Center, New Delhi, explains more about the problems wheat farmers face in our country. “There are several first-generation (productivity) and second-generation (sustainability) problems. In the green revolution era, policy-supported environment led to a large increase in rice cultivation in northwestern India mainly in Punjab and Haryana which are ecologically less suitable for rice cultivation due to predominantly light soils.”

He explains that this policy-supported intensive agriculture led to unsustainable groundwater use for irrigation and in turn groundwater scarcity. There was also post-harvest residue burning to make way for the timely sowing of wheat. He is one of the authors of the paper.

Poor infrastructure

He adds that there are enough groundwater resources supported with higher monsoon rainfall in eastern Indian states like Bihar. But due to lack of enough irrigation infrastructure, farmers are not able to make use of natural resources there.

“So we need better policies in eastern India to expand the irrigation and thus increase agriculture productivity. This will also release some pressure from northwestern Indian states,” he concludes.

Preliminary studies show that people who have been vaccinated with Covishield have protection against the double mutant variant (B.1.617) first found in India.

Studies by researchers at the Hyderabad-based Centre for Cellular and Molecular Biology (CCMB), a Council of Scientific and Industrial Research (CSIR) lab, found that protection against the double mutant variant was also seen both when convalescent plasma from people who have been infected and have already recovered was tested in the lab.

“Both Covishield vaccinated sera and convalescent sera were found to offer protection against the double mutant variant (B.1.167),” said Dr. Rakesh Mishra, Director, CCMB. “This is only a preliminary study involving four-five people for each group, and was carried out among young people who have recovered from prior infection and another group of people who have received Covishield vaccine.”

Dr. Mishra said that in about 10 days, studies involving more people from both groups — who have recovered and who have been vaccinated — will be done. Also, the study will involve older people to understand the level of protection conferred by previous infection and by the Covishield vaccine.

“The study, though preliminary, does show that vaccination with Covishield offers protection against the double mutant variant. So people should go ahead and get vaccinated quickly,” said Dr. Mishra. “The preliminary study also suggests that convalescent plasma may offer protection against reinfection with the double mutant variant. Studies using plasma from more recovered and vaccinated people of different age groups are needed for confirmation.”

The institute is carrying out similar studies using plasma from people vaccinated with Covaxin.

The B.1.617 variant has two mutations — E484Q and L425R — of concern.

According to Dr. Vinod Scaria, a senior scientist at the Delhi-based Institute of Genomics and Integrative Biology (IGIB), a CSIR lab, the two mutations have individually been found to make the virus more infectious and evade antibodies. But the combined effect of these two mutations when found together has not been determined.

“The two mutations, when found together, could alter the structure of the spike protein in unanticipated ways. Therefore, we cannot predict with utmost accuracy whether the two mutations when present together will further increase or reduce the infectivity and ability to evade specific antibodies. The CCMB study shows that serum from people vaccinated with Covishield could inhibit the B.1.167 variant of the virus. More detailed studies involving a larger number of people is the way forward,” Dr. Scaria said.

Studies found that in the lab, the convalescent plasma from recovered people was able to neutralise the double mutant variant almost completely even when the plasma was diluted 20-fold. The relative viral load seen when the plasma was diluted 40- and 80-fold was about 2-3%. The relative viral load reached nearly 65% only when the plasma was diluted 320-fold, showing the effectiveness of convalescent plasma in neutralising the double mutant variant.

Neutralisation studies carried out using plasma from Covishield-vaccinated people showed that the level of protection against the double mutant variant was far superior than convalescent plasma.

Even when the plasma from Covishield-vaccinated people was diluted 80-fold, the relative viral load was almost nil. In simple terms, this means that even 80-fold diluted plasma is effective against the double mutant variant. It was only when the plasma of vaccinated people was diluted 320-fold did the relative viral load increase and reach nearly 55%.

In Maharashtra, the double mutant variant (B.1.617) was found in more than 60% of samples taken for genome sequencing.

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Unlike its popular movie incarnations, Tyrannosaurus rex - the giant meat-eating dinosaur from the Cretaceous period - walked slower than previously thought, most likely ambling around at human walking speed, new Dutch research found.

Working with a 3-dimensional computer model of "Trix", a female T. rex skeleton at the Dutch Naturalis museum, researcher Pasha van Bijlert added computer reconstructions of muscles and ligaments to find that it's likely that the dinosaur's preferred speed was 4.61 kms (2.86 miles) an hour, close to the walking pace of humans and horses.

In an article on the movement of dinosaurs in the Royal Open Society Science journal, Van Bijlert and his co-authors said T. rex's huge tail played an important part in its locomotion.

They looked at how the animal would achieve a natural frequency of movement, factoring in not only leg muscles as in previous studies but also tail movement, that would minimize the amount of energy used.

"The tail would sway up and down with each step (like a giraffe's neck). If the step rhythm and tail natural frequency were matched, the tail would resonate, maximizing energy storage," Van Bijlert said on Twitter.

By calculating the T. Rex's step rhythm researchers estimated its walking speed.

However, it's too soon to assume a human could have outrun a T. rex: the researchers said they were looking at the fearsome predator's walking pace and still researching its possible top speeds. There's also no possibility of it being put to the test as the species died out more than 60 million years before people appeared on Earth.

SpaceX on Wednesday bumped its next astronaut launch by a day because of dangerously high waves and wind offshore.

Liftoff is now scheduled for early Friday morning from NASA’s Kennedy Space Center, when better weather is expected.

The SpaceX Dragon capsule has the ability to abort the launch all the way to orbit in case of an emergency. That’s why good weather is needed not only at the Florida launch site, but all the way up the East Coast and across the North Atlantic to Ireland.

The four astronauts — from the U.S., Japan and France — will spend six months at the International Space Station.

This will be SpaceX's third launch of astronauts for NASA in less than a year. NASA turned to private companies once the shuttle program ended to haul not only supplies to the space station, but also people. SpaceX began delivering cargo in 2012 and flew its first crew up last May.

NASA has logged another extraterrestrial first on its latest mission to Mars: converting carbon dioxide from the Martian atmosphere into pure, breathable oxygen, the U.S. space agency said on Wednesday.

The unprecedented extraction of oxygen, literally out of thin air on Mars, was achieved on Tuesday by an experimental device aboard Perseverance, a six-wheeled science rover that landed on the Red Planet on February 18 after a seven-month journey from Earth.

In its first activation, the toaster-sized instrument dubbed MOXIE, short for Mars Oxygen In-Situ Resource Utilisation Experiment, produced about 5 grams of oxygen, equivalent to roughly 10 minutes’ worth of breathing for an astronaut, NASA said. Although the initial output was modest, the feat marked the first experimental extraction of a natural resources from the environment of another planet for direct use by humans.

“MOXIE isn’t just the first instrument to produce oxygen on another world,” Trudy Kortes, director of technology demonstrations within NASA’s Space Technology Mission Directorate, said in a statement. She called it the first technology of its kind to help future missions “live off the land” of another planet.

How does it work?

The instrument works through electrolysis, which uses extreme heat to separate oxygen atoms from molecules of carbondioxide, which accounts for about 95% of the atmosphere on Mars.

The remaining 5% of Mars’ atmosphere, which is only about 1%as dense Earth’s, consists primarily of molecular nitrogen and argon. Oxygen exists on Mars in negligible trace amounts.

But an abundant supply is considered critical to eventual human exploration of the Red Planet, both as a sustainable source of breathable air for astronauts and as a necessary ingredient for rocket fuel to fly them home.

The volumes required for launching rockets into space from Mars are particularly daunting.

According to NASA, getting four astronauts off the Martian surface would take about 7 metric tons of rocket fuel, combined with 25 metric tons of oxygen.

Transporting a one-ton oxygen-conversion machine to Mars is more practical than trying to haul 25 tons of oxygen in tanks from Earth, MOXIE principal investigator Michael Hecht, of the Massachusetts Institute of Technology, said in NASA’s news release.

Astronauts living and working on Mars would require perhaps one metric ton of oxygen between them to last an entire year, Mr. Hecht said.

MOXIE is designed to generate up to 10 grams per hour as a proof of concept, and scientists plan to run the machine at least another nine times over the next two years under different conditions and speeds, NASA said.

The first oxygen conversion run came a day after NASA achieved the historic first controlled powered flight of an aircraft on another planet with a successful take-off and landing of a miniature robot helicopter on Mars.

Like MOXIE, the twin-rotor chopper dubbed Ingenuity hitched a ride to Mars with Perseverance, whose primary mission is to search for fossilised traces of ancient microbes that may have flourished on Mars billions of years ago.

IIT Kharagpur has successfully commercialised its flagship healthcare product COVIRAP the novel diagnostic technology to zero on infectious diseases including COVID-19, the institute said Wednesday.

The product, developed by lead researchers Professor Suman Chakraborty, Dr Arindam Mondal and their research group, has been licensed for commercialisation to the Rapid Diagnostic Group of Companies, India and Bramerton Holdings LLC, USA.

A virtual press meet was organised on Wednesday by the institute in which the researchers were present along with institute director to make the announcement.

"The above move has taken place at a critical juncture when the recent spurt in COVID-19 infection, commonly known as the second wave, has been threatening to spread more rapidly than ever before," IIT Kharagpur Director Prof V.K. Tewari said.

"Moreover, the commercialisation of COVIRAP will initiate complete indigenisation and availability of a large range of affordable healthcare products in the Indian market as well as deep trenches of a large global market that is literally starving for the need of such technology," Mr. Tewari said.

Bramerton Holdings has signed a record deal for securing global rights for commercially disseminating the COVIRAP technology developed at IIT Kharagpur in various geographical locations outside the territory of the Indian subcontinent, an institute spokesperson informed.

Rapid Diagnostic has also initiated adapting the COVIRAP technology platform for COVID-19 and tuberculosis, in collaboration with IIT Kharagpur, the spokesperson said.

The research team has now developed a more advanced version of COVIRAP using a step-wise isothermal nucleic acid testing technology for the rapid diagnostics of pathogenic infections including SARS-CoV-2 in individuals, Mr. Chakraborty said.

The COVID-19 diagnostic test can be conducted directly from human swab samples in the portable device developed by the team, without requiring any separate facility for RNA extraction.

Results in 45 minutes

The results can be made available within 45 minutes of obtaining the patient sample, he said.

The kit has also been also supplemented with a free smartphone app to facilitate unambiguous results interpretation and automated dissemination to the patients.

For use of the test, the nasal, as well as oral swab samples, are diluted in a solution and tested in the portable device by mixing with reagents that are supplied in a pre- mixed form, Mr. Chakraborty said, adding the test runs automatically in the device without intermediate manual intervention.

"We have conducted field trials for running the tests with the help of unskilled personnel outside controlled laboratory ambience, with no compromise in quality of the test outcome. The entire sample-to-result procedure may be conducted in the portable device, virtually anywhere and with minimal training thus making the process of testing more effective for community-level screening and early detection of any emerging infection outbreak.

"This may act as a key to arrest community level spreading of the infection," Mr. Chakraborty hoped.

COVIRAP promises its reach to the grassroots level in catering to the needs of the last person of the society, he added.

The researchers claimed COVIRAP test overcomes several potential bottlenecks faced by similar other tests in the past, for instance, poor performance outside highly controlled laboratory and lack of simple, affordable, yet generic and universal instrument that may be used for home-based testing and community healthcare for a wide variety of infectious and non-infectious diseases.

Recognising the impact of the COVIRAP technology in meeting the long-standing demands of high-quality community-level testing, IIT Kharagpur has further initiated the procedure of deploying this product for on-campus use to detect possible novel coronavirus infection, the institute spokesperson said.

Patents centred around this innovation have been filed in the India, USA, several other countries, in the name of IIT Kharagpur.

The foreign filing license has been granted recently.

Commercialisation and use in the USA and Europe under the Emergency Use Authorization (EUA) process are currently underway.

Published in Cell

Scientists have now grown monkey embryos containing human stem cells for the first time, raising several ethical questions. Fertilised eggs extracted from monkeys (Macaca fascicularis) were injected with human extended pluripotent stem cells. Out of the injected 132 embryos, three survived 19 days after fertilisation. Scientists hope that such hybrids could be used as models for drug tests and to grow organs for transplants. Expressing concern, Julian Savulescu and Julian Koplin from the University of Melbourne wrote in a statement, “The challenge for chimera research is that there is no agreed-upon account of moral status. We need to work out what properties confer a right to life, a right to not be experimented on without consent and a right to live freely.”

DNA in sediments

Published in Science

Skeletal remains and DNA collected from them have helped archeologists tell stories of our long-lost relatives. But what to do when such bones and teeth are not available? Study the sediments, says a new paper that extracted nuclear DNA from cave sediments and showed that the Neanderthal population lived in the region 100,000 years ago.

Chagyrskaya cave in the Altai Mountains of southern Siberia. Credit: Richard G. Roberts 

Honey history

Published in Nature Communications

Researchers studying pot fragments from 12 archaeological sites in Central Nigeria were in for a sweet surprise when they found that it contained beeswax. It implied that the Nok people who lived in the region about 3,500 years ago consumed honey and also heated the wax to be used as a coating for the cooking pots or to store honey.

Marine magic

Published in Science Advances

Inspired by the porous and layered cuttlefish bone, researchers have 3D printed new microstructures and materials that show many adaptations. The team hopes that this can help 3-D print implants for injuries. "The implants would more closely mimic the porous nature of the human bone and would promote the growth of the bone itself inside the scaffold. As the bone grows, the scaffold biodegrades, and if everything goes well, in the end, the scaffold is gone, and the patient has new bones in the right places." explains the corresponding author of the work A. Pereira in a release.

It's all in the gut

Published in Cell Reports

There is a connection between sugar, mosquitoes and malaria. A new study has shown that when mosquitoes are given a sugar diet, it increases the abundance of a particular bacteria in the mosquito's gut. This in turn raises the gut’s pH and leads to an increase in the number of malaria-causing parasites in its midgut. The team writes that this finding may help in the development of new preventive strategies.

Indigenously developed COVID-19 vaccine, Covaxin, neutralises multiple variants of SARS-CoV-2 and effectively works against the double mutant strain as well, the Indian Council of Medical Research (ICMR) said on Wednesday.

Bharat Biotech's Covaxin has received Emergency Use Authorizations (EUAs) for COVID-19 treatment in India and in several countries across the globe with another 60 in the process.

"ICMR study shows Covaxin neutralises against multiple variants of SARS-CoV-2 and effectively neutralises the double mutant strain as well," the ICMR tweeted.

ICMR-National Institute of Virology has successfully isolated and cultured multiple variants of concern of SARS-CoV-2 virus: B.1.1.7 (the UK variant), B.1.1.28 (Brazil variant) and B.1.351 (South Africa variant).

ICMR-NIV has demonstrated the neutralisation potential of Covaxin against the UK variant and Brazil variant, the apex health research body said.

ICMR-NIV recently has been successful in isolating and culturing the double mutant strain B.1.617 SARS-CoV-2 identified in certain regions of India and several other countries, the ICMR stated.

"Covaxin has been found to effectively neutralise the double mutant strain as well," it said.

Eight cases of serious, unusual blood clots associated with low levels of blood platelets, one of which was fatal, have been seen in the U.S. after administration of Johnson & Johnson COVID-19 vaccine. On April 20, European Medicines Agency’s safety committee (PRAC) based on these cases “concluded that a warning about unusual blood clots with low blood platelets should be added to the product information for COVID-19 Vaccine Janssen”. The safety committee also “concluded that these events should be listed as very rare side effects of the vaccine”. As of 13 April 2021, over seven million people had received the vaccine in the U.S.

In a press release, the EMA said that it found “possible link to very rare cases of unusual blood clots with low blood platelets” following administration of Johnson and Johnson vaccine.

On April 13, the U.S. called for a pause in Johnson & Johnson vaccine use when six cases of a rare blood-clotting disorder were seen in the vaccinated people.

All the eight cases were seen in those under 60 years of age within three weeks after vaccination, the majority being in women. “Based on the currently available evidence, specific risk factors have not been confirmed,” the EMA said in a release.

Kai Kupferschmidt, a science journalist, tweeted saying that Sabine Straus, Chair of EMA, told the press that though the U.S. paused vaccination on April 13, cases can still occur for three weeks after immunisation. “So we still have to wait and see if there are more cases coming in, so it's too early to say anything about the real occurrence of the cases,” Ms. Straus had apparently warned.

“At this moment, it's not possible to identify clear risk factors for the occurrence of these very rare events, such as gender or age”, Ms. Straus told the press.

The safety committee also noted that the blood clots occurred mostly at unusual sites such as in veins in the brain (cerebral venous sinus thrombosis, CVST) and the abdomen (splanchnic vein thrombosis) and in arteries, together with low levels of blood platelets and sometimes bleeding. The cases reviewed had close similarity to cases seen after administration of AstraZeneca vaccine.

The EMA stressed that the reported “combination of blood clots and low blood platelets is very rare, and the overall benefits of COVID-19 Vaccine Janssen [owned by Johnson and Johnson] in preventing COVID-19 outweigh the risks of side effects”.

The EMA listed out the symptoms to look out for within three weeks after vaccination. These include shortness of breath; chest pain; swelling in the leg; persistent abdominal pain; neurological symptoms, including severe or persistent headaches or blurred vision; and skin bruising beyond the site of injection.

The safety committee emphasised the importance of prompt specialist medical treatment. “By recognising the signs of blood clots and low blood platelets and treating them early, healthcare professionals can help those affected in their recovery and avoid complications,” the committee said.

For the first time, NASA is putting its trust in a recycled SpaceX rocket and capsule for a crew.

Astronaut Megan McArthur takes special pleasure in the reused spacecraft set to soar Thursday morning. In “a fun twist,” she’ll sit in the same seat in the same capsule as her husband, Bob Behnken, did last spring for a test flight to the International Space Station. “It's kind of a fun thing that we can share. I can see him and say, ‘Hey, can you hand over the keys. I'm ready now to go,' “ she said in a recent interview with The Associated Press. She and her three crewmates will spend six months at the space station.

This will be SpaceX’s third crew flight for NASA from Florida's Kennedy Space Center in under a year. The commercial flights ended the U.S.'s reliance on Russian rockets launched from Kazakhstan to get astronauts to and from the space station after the shuttles retired.

SpaceX’s Benji Reed noted Tuesday the private company already has put six people in space — as many as NASA's Project Mercury did back in the early 1960s when it launched the first Americans. The upcoming flight will boost that number to 10.

Some highlights of the SpaceX flight:

Use, recycle, repeat: Both the Dragon capsule and Falcon rocket for this mission have soared once before. The capsule launched the first SpaceX crew last May, while the rocket hoisted the second set of astronauts, who are still at the space station.

For SpaceX, recycling is key to space exploration, Reed said, lowering costs, increasing flights and destinations, and allowing more kinds of people to jump on board. Each capsule is designed to launch at least five times with a crew.

SpaceX and NASA are assessing how many times a Falcon can safely launch astronauts. For satellites, Falcons can be used for 10 flights. The company uses the same kind of rocket and similar capsules for station supply runs, and recycles those, too.

U.S.-French-Japanese Crew: This is the most internationally diverse crew yet for SpaceX. NASA astronaut Shane Kimbrough, a retired Army colonel, is the spacecraft commander, with McArthur, an oceanographer, as his pilot. Thomas Pesquet, a former Air France pilot, is representing the European Space Agency. Engineer Akihiko Hoshide has worked for the Japanese Space Agency for nearly 30 years and helped build the space station.

All but McArthur have already visited the 260-mile-high (420-kilometer-high) outpost. But she's ventured 100 miles (160 kilometers) higher on the space shuttle, taking part in NASA's final Hubble Space Telescope mission in 2009. The four have started a new recycled-rocket tradition for SpaceX crews, writing their initials in the soot of their booster.

Bon appetit: With French and Japanese astronauts flying together, dining promises to reach new heights. Hoshide is taking up curry and rice, as well as canned fish and yakitori — grilled and skewered chicken — but no sushi.

Pesquet had a Michelin-starred chef whip up some French delicacies: beef with red wine and mushroom sauce, truffled potato and onion tart, and almond tart with caramelized pears. There are also Crepes Suzette.

Pesquet said last weekend he had “some national pressure” to fly French cuisine. His crewmates also had high expectations: “OK, we're flying with a Frenchman, it better be good."

Coming and going: Five days after this crew's arrival at the space station, the one Japanese and three U.S. astronauts who have been up there since November will strap into their SpaceX capsule to come home.

NASA wants some time in orbit between the two crews, so the newcomers can benefit from their colleagues' experience up there.

SpaceX is targeting an April 28 splashdown in the Gulf of Mexico off the coast of Tallahassee, Florida. The company already is conferring with the Coast Guard to prevent pleasure boats from swarming the area like they did for the first SpaceX crew's splashdown in August. More Coast Guard ships will be on patrol this time.

An orally administered antiviral drug initially developed to treat influenza can significantly decrease novel coronavirus levels in hamsters, holding out promise of a pill to combat COVID-19, say researchers.

Scientists from the National Institutes of Health (NIH) in the U.S. and the University of Plymouth in the U.K. found that MK-4482, also called Molnupiravir, was effective when provided up to 12 hours before or 12 hours after infection with SARS-CoV-2, the novel coronavirus that causes COVID-19.

The drug can also decrease damage it causes to lungs, states the study conducted on hamsters.

Published in the journal Nature Communications on April 16, it suggests that treatment with MK-4482 could potentially mitigate high-risk exposure to SARS-CoV-2 and might be used to treat established SARS-CoV-2 infection alone or in combination with other agents.

Also read: Jubilant Pharma develops oral formulation of Remdesivir

"In contrast to vaccines against SARS-CoV-2, we really don't have many drugs that are effective against the virus. This is an exciting result that identifies MK-4482 as an additional antiviral against SARS-CoV-2,” said Michael Jarvis, associate professor of Virology and Immunology at the University of Plymouth and a guest researcher at NIH. “The drug, also called Molnupiravir, is in the final stages of human clinical trials in SARS-CoV-2 infected patients.”

If human data shows a similar antiviral effect, it may be suitable for use as an orally administered pill following exposure to the virus, similar to the way Tamiflu is used for influenza, the researchers said.

“I think this additional control measure could prove to be really useful in the current pandemic," Jarvis added.

Though Remdesivir has already been approved by the U.S. Food and Drug Administration under emergency use authorization (EUA) it must be provided intravenously, making its use primarily limited to clinical settings at later stages of the disease.

The research group developed a model last year which uses hamsters to mimic SARS-CoV-2 infection and mild disease in people.

The current research involved three groups of hamsters — a pre-infection treatment group, a post-infection treatment group and an untreated control group. The scientists administered MK-4482 orally in the two treatment groups every 12 hours for three days. Their study found that the animals in each of the treatment groups had 100 times less infectious virus in their lungs than the control group.

Animals in the two treatment groups also had significantly fewer lesions or tissue damage in the lungs than the control group, according to the researchers.

The researchers noted that MK-4482 has been shown to inhibit the replication of other related human coronaviruses, Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS) in mouse models.

In their earlier research, the team determined the inhibitory effect of the drug on SARS-CoV-2 replication in human lung cells in the laboratory. The treatment resulted in a significant decrease in SARS-CoV-2 replication when compared to no drug controls, they said. The drug also demonstrated only minimal cellular toxicity.

Scientists studying Chile's parched Atacama desert, the world's driest, have discovered the remains of a previously unknown species of dinosaur that millions of years ago lived among lush greenery in what is now a moonscape of rock and sand.

A team led by Chilean geologist Carlos Arévalo unearthed the remains of Arackar licanantay, which means "Atacama bones" in the Kunza language, 75 kilometers south of the desert city ​​of Copiapó. The so-called titanosaur had a small head and long neck and tail, as well as an unusually flat back compared with others like it.

Recent paleontological studies suggest Arackar lived amid flowering plants, ferns and palm trees during the Cretaceous period 66-80 million years ago. Parts of the Atacama today, by contrast, have gone without rain for one hundred years and support little plant or animal life.

The discovery of a titanosaur on the west side of South America's Andes Mountains is rare, though several species have been found in Argentina and Brazil, further east.

The dinosaur's remains were first discovered in the 1990s and were described by the scientists in the journal Cretaceous Research.

Arackar also appears smaller in size compared with some other titanosaurs. The Argentinosaurus, discovered on the east side of the Andes in neighbouring Argentina, was more than four times as long, scientists say.

The dinosaur's remains will eventually be exhibited in Chile's Museum of Natural History, though that is currently closed due to coronavirus restrictions.

Ferocious tyrannosaur dinosaurs may not have been solitary predators as long envisioned, but more like social carnivores such as wolves, new research unveiled Monday found.

Paleontologists developed the theory while studying a mass tyrannosaur death site found seven years ago in the Grand Staircase-Escalante National Monument in southern Utah, one of two monuments that the Biden administration is considering restoring to their full size after former President Donald Trump shrunk them.

Using geochemical analysis of the bones and rock, a team of researchers with the University of Arkansas determined that the dinosaurs died and were buried in the same place and were not the result of fossils washing in from multiple areas.

The new Utah site is the third mass tyrannosaur grave site that’s been discovered in North America — bolstering a theory first developed 20 years ago that they lived in packs. However, more research needs to be done to make that argument, said Kristi Curry Rogers, a biology professor at Macalester College who wasn’t involved in the research but reviewed the finding Monday.

“It is a little tougher to be so sure that these data mean that these tyrannosaurs lived together in the good times,” Rogers said. “It’s possible that these animals may have lived in the same vicinity as one another without traveling together in a social group, and just came together around dwindling resources as times got tougher.”

In 2014, Bureau of Land Management paleontologist Alan Titus discovered the site, which was later named the Rainbows and Unicorns quarry because of the vast array of fossils contained inside. Excavation has been ongoing since the site's discovery because of the size of the area and volume of bones.

“I consider this a once-in-a-lifetime discovery for myself,” Titus told reporters during a virtual news conference. “I probably won’t find another site this exciting and scientifically significant during my career.”

The social tyrannosaurs theory began over 20 years ago when more than a dozen tyrannosaurs were found at a site in Alberta, Canada. Another mass death site in Montana again raised the possibility of social tyrannosaurs. Many scientists questioned the theory, arguing that the dinosaurs didn't have the brainpower to engage in sophisticated social interaction, Titus said.

“Going that next step to understand behavior and how animals behave requires really amazing evidence,” Joseph Sertich, curator of dinosaurs at the Denver Museum of Nature & Science, said at the news conference. “I think that this site, the spectacular collection of tyrannosaurs but also the other assembled pieces of evidence ... pushes us to the point where we can show some evidence for behavior.”

In addition to the tyrannosaurs, researchers have also found seven species of turtles, multiple fish and ray species, two other kinds of dinosaurs and a nearly complete skeleton of a juvenile Deinosuchus alligator. These other animals do not appear to have all died together.

Paleontology groups have been among those pushing the federal government to restore the Bears Ears National Monument and Grand Staircase-Escalante to their original sizes to protect the region’s rich paleontological and archaeological record.

Interior Secretary Deb Haaland visited southern Utah earlier this month as she prepared to submit recommendations on whether to reverse Trump’s decision to downsize the monuments. Titus said he showed Haaland some of the fossils at his lab during her visit and said she “appreciated getting to see the material.”

“The (Bureau of Land Management) is protecting these fossils as national treasures.” Titus said. “They’re part of the story of how North America came to be and how ultimately we came to be.”

In dense tropical forests in Sierra Leone, scientists have rediscovered a coffee species not seen in the wild in decades — a plant they say may help secure the future of this valuable commodity that has been imperiled by climate change.

The researchers said on Monday that the species, called Coffea stenophylla, possesses greater tolerance for higher temperatures than the Arabica coffee that makes up 56% of global production and the robusta coffee that makes up 43%. The stenophylla coffee, they added, was demonstrated to have a superior flavour, similar to Arabica.

Botanist Aaron Davis, who led the study published in the journal Nature Plants, said stenophylla was farmed in parts of West Africa and exported to Europe until the early 20th century before being abandoned as a crop after robusta's introduction.

Many farmers throughout the world's coffee-growing belt already are experiencing climate change's negative effects, an acute concern for the multibillion dollar industry.

Arabica's flavour is rated as superior and brings higher prices than robusta, which is mainly used for instant coffee and coffee blends. But Arabica has limited resilience to climate change and research has shown its global production could fall by at least 50% by mid-century.

Stenophylla grows at a mean annual temperature of 24.9℃ — 1.9℃ higher than robusta coffee and up to 6.8°C higher than Arabica coffee, the researchers said.

The stenophylla rediscovery, Davis said, may help in the "future-proofing" of a coffee industry that supports the economy of several tropical countries and provides livelihoods for more than 100 million farmers. While 124 coffee species are known, Arabica and robusta comprise 99% of consumption.

"The idea is that stenophylla could be used, with minimum domestication, as a high-value coffee for farmers in warmer climates," said Davis, head of coffee research at Britain's Royal Botanic Gardens, Kew.

"For the longer term, stenophylla provides us with an important resource for breeding a new generation of climate-resilient coffee crop plants, given that it possesses a great flavour and heat tolerance. If the historic reports of resistance to coffee leaf rust and drought tolerance are found to be correct, this would represent further useful assets for coffee plant breeding," Davis added.

Leaf rust is a fungal disease that has devastated coffee crops in Central and South America.

The study included flavour assessments involving 18 coffee-tasting experts. Stenophylla was found to have a complex flavour profile, with natural sweetness, medium-high acidity, fruitiness and good "body" — the way it feels in the mouth.

In December 2018, Davis and study co-authors Jeremy Haggar of the University of Greenwich and coffee development specialist Daniel Sarmu searched for stenophylla in the wild. They initially spotted a single plant in central Sierra Leone. About 140 km away in southeastern Sierra Leone, they found a healthy wild stenophylla population.

"Both locations were thick tropical forest, but stenophylla tends to occur on drier, more open areas: ridges, slopes and rocky areas," Davis said.

Stenophylla had not been seen in the wild in Sierra Leone since 1954 and anywhere since the 1980s in Ivory Coast, Davis said. A few examples were held in coffee research collections.

Davis said stenophylla is threatened with extinction amid large-scale deforestation in the three countries where it has been known to grow in the wild: Sierra Leone, Guinea and Ivory Coast.

Unlike the red and occasionally yellow fruit of Arabica and robusta plants, stenophylla's fruit are intense black. The coffee beans are inside the fruit.

"I think we're hugely optimistic for the future that stenophylla can bring," said Jeremy Torz, co-founder of the specialty coffee business Union Hand-Roasted Coffee in East London where part of the taste-testing was held.

NASA's miniature robot helicopter Ingenuity performed a successful takeoff and landing on Mars early on Monday, achieving the first powered, controlled flight by an aircraft over the surface of another planet, the U.S. space agency said.

The solar-powered whirligig's debut on the Red Planet marked a 21st-century Wright Brothers moment for NASA, which said success could pave the way for new modes of exploration on Marsand other destinations in the solar system, such as Venus and Saturn's moon Titan.

Mission managers at NASA's Jet Propulsion Laboratory (JPL) near Los Angeles burst into applause and cheers as engineering data beamed back from Mars confirmed that the 4-pound (1.8-kg) twin-rotor helicopter had performed its maiden 40-second flight as planned about three hours earlier.

The robot rotorcraft was programmed to ascend 10 feet (3 meters) straight up, then hover and rotate in place over the Martian surface for half a minute before settling back down on its four legs. JPL officials said data returned from Mars showed that this had in fact occurred.

Also Read | How do astronauts write in space?

During NASA's own coverage of the event livestreamed from JPL headquarters, NASA also displayed the first images from the flight.

A black-and-white photo taken by a downward-pointing onboard camera while the helicopter was aloft showed the distinct shadow cast by Ingenuity in the Martian sunlight onto the ground just below it.

A snippet of color video footage captured by a separate camera mounted on the NASA's Mars rover Perseverance, parked about 200 feet away, showed the helicopter in flight against the orange-colored landscape surrounding it.

"We can now say that human beings have flown an aircraft on another planet," said MiMi Aung, Ingenuity project manager at JPL.

The 300-million-year-old shark’s teeth were the first sign that it might be a distinct species. The ancient chompers looked less like the spear-like rows of teeth of related species. They were squatter and shorter, less than an inch long, around 2 centimeters.

“Great for grasping and crushing prey rather than piercing prey,” said discoverer John-Paul Hodnett, who was a graduate student when he unearthed the first fossils of the shark at a dig east of Albuquerque in 2013.

This week, Hodnett and a slew of other researchers published their findings in a bulletin of the New Mexico Museum of Natural History & Science identifying the shark as a separate species.

He named the 6.7-foot (2 meter) monster Dracopristis hoffmanorum, or Hoffman’s Dragon Shark, in honor of the New Mexico family that owns the land in the Manzano Mountains where the fossils were found. Hodnett says the area is rife with fossils and easy to access because of a quarry and other commercial digging operations.

The name also harkens to the dragon-like jawline and 2.5-foot (0.75-meter) fin spines that inspired the discovery’s initial nickname, “Godzilla Shark.”

The formal naming announcement followed seven years of excavation, preservation and study.

The 12 rows of teeth on the shark's lower jaw, for example, were still obscured by layers of sediment after excavation. Hodnett only saw them by using an angled light technique that illuminates objects below.

The recovered fossil skeleton is considered the most complete of its evolutionary branch — ctenacanth — that split from modern sharks and rays around 390 million years ago and went extinct around 60 million years later.

Back then, eastern New Mexico was covered by a seaway that extended deep into North America. Hodnett and his colleagues believe that Hoffman’s dragon shark most likely lived in the shallows along the coast, stalking prey like crustaceans, fish and other sharks.

New Mexico's high desert plateaus have also yielded many dinosaur fossils, including various species of tyrannosaurus that roamed the land millions of years ago when it was a tropical rain forest.

Google Doodle today celebrates the 151st birth anniversary of Russian surgeon, poet, and author Dr. Vera Gedroits. She was the first female military surgeon in Russia and one of the first female professors of surgery. She was also the first woman physician for the Russian royal family.

She was known for her innovations in the field of battlefield medicine. She adopted the method of laparotomy (surgical cut into the abdominal cavity) for treating penetrating wounds.

She has authored several papers on nutrition, surgical treatments, and a book on her experiences as an industrial doctor. In 1912, she was awarded a doctorate of medicine by the University of Moscow, for her work in hernia repair. In 1914, she published another book titled Surgical Discourses for Nurses and Doctors.

She was diagnosed with cancer in 1931 and died in March 1947, aged 78.

In 2007, an article in the journal Clinical and Investigative Medicine lamented the fact that the world has forgotten Gedroits story. “It is a wonder that her significant and diverse accomplishments are detailed in so few sources...It is clear that her surgical accomplishments deserve recognition, at least as much as that heaped upon those who effected almost identical feats over a decade later,” wrote Ben J. Wilson from the University of Calgary.

“The limited audience to which Gedroits presented her work defined its limited impact. Russia failed to show, and the West failed to see, Gedroits’ discoveries...The tale of Vera Gedroits is but one illustration of an unfortunately prevalent cycle of forgetting and relearning,” wrote Prof. Wilson.

NASA is hoping to make history early on Monday when the Ingenuity Mars Helicopter attempts the first powered, controlled flight on another planet.

The space agency had originally planned the flight for April 11 but postponed it over a software issue that was identified during a planned high-speed test of the aircraft's rotors.

The issue has since been resolved, and the 1.8 kilograms drone could achieve its feat by around 7.30 GMT.

Data, however, won’t arrive until several hours later, and NASA will begin a livestream at 10.15 GMT.

“Each world gets only one first flight,” MiMi Aung, the Ingenuity project manager, said before the first attempt.

The first powered flight on Earth was achieved by the Wright brothers in 1903 in Kitty Hawk, North Carolina. A piece of fabric from that plane has been tucked inside Ingenuity in honour of that feat.

The helicopter travelled to Mars attached to the underside of the rover Perseverance, which touched down on the planet on February 18 on a mission to search for signs of extraterrestrial life.

Ingenuity’s goal, by contrast, is to demonstrate its technology works, and it won't contribute to Perseverance’s science goals.

But it is hoped that Ingenuity can pave the way for future flyers that revolutionise our exploration of celestial bodies because they can reach areas that rovers can’t go, and travel much faster.

The timing of the helicopter flight is chosen with the weather on Mars in mind. Wind is the big unknown and could jeopardise the mission.

The flight is challenging because the air on Mars is so thin — less than one percent of the pressure of Earths atmosphere.

That makes it much harder to achieve lift, even though it will be partly aided by a gravitational pull that is a third of Earth’s.

High-res video

The helicopter will rise for about six seconds, hover and rotate for about 30 seconds, then go back down.

The flight will be autonomous, pre-programmed into the aircraft because of the 15 minutes it takes for signals to travel from Earth to Mars.

Ingenuity itself will analyse its position with respect to the Martian surface.

After the flight, Ingenuity will send Perseverance technical data on what it has done, and that information will be transmitted back to Earth.

This will include a black and white photo of the Martian surface that Ingenuity is programmed to snap while flying.

Later, once its batteries have charged up again, Ingenuity is to transmit another photo — in colour, of the Martian horizon, taken with a different camera.

But the most spectacular images are supposed to come from the rover Perseverance, which will film the flight from a few meters away.

Shortly after this filming, six videos of 2.5 seconds each will be sent to Earth. NASA hopes at least one of them will show the helicopter in flight.

The entire video will be sent over the following few days.

“There will be surprises, and you will be learning about them right at the same time that we will. So let's all get the popcorn,” said Elsa Jensen, who oversees the cameras on the rover.

‘High risk’

Four outcomes are possible, said Ms. Aung: full success, partial success, insufficient or no data coming back, or failure.

If the flight is a success, NASA plans another no more than four days later. It plans as many as five altogether, each successively more difficult, over the course of a month.

NASA hopes to make the helicopter rise five meters and then move laterally.

Ingenuity’s “lifetime will be determined by how well it lands” each time, said Ms. Aung — meaning whether it crashes.

“Once we get to the fourth and fifth flight, we’ll have fun,” she said. “We are going to take very bold flights and take high risk.”

Very little of today’s world resembles Planet Earth from 500 years ago. In fact, only about 3% of land surfaces might be ecologically intact — still home to their full range of native species and unblemished by human activity, according to new research.

The finding -- published in the journal Frontiers in Forests and Global Change — is far lower than previous estimates based on satellite images, which suggested around 20% to 40% of land ecosystems were undamaged.

For the new study, however, scientists conducted an extensive survey of forest cover and species losses to understand better what was happening beneath the world’s tree canopies.

“I was particularly surprised to see how low it really is,” said Andrew Plumptre, a conservation biologist at the University of Cambridge. “It shows how rare such intact places are. It’s scary just how little the world looks like what it was just 500 years ago.”

The term ecosystem describes the complex relationships within a natural area that, altogether, help to sustain a healthy and balanced diversity of life. Lose just one or two key species, and the whole system could fall apart.

Today’s still-pristine habitats, containing the same species abundance as in the year 1500 A.D., were mostly found in regions considered less hospitable for humans, including the Sahara Desert and chilly regions of Greenland and northern Canada. Other intact habitats were in areas under extreme pressure from deforestation and development, including parts of the Amazon in Latin America.

The authors argue that these areas should be a priority for future conservation. Though currently, only 11% of these areas are under protection, the study found.

“The idea of focusing on intact areas is so that you don’t have to work to remove the human footprint,” Plumptre said.

Some scientists, however, questioned the extremely low figure, saying it could be attributed to the study using a particularly narrow definition of “intact habitats” — those with their full, historical collection of animals and plants.

“We need practical actions to ensure species and ecosystems survive,” said Stuart Pimm, a conservation scientist at Duke University.

He also questioned the study authors’ call for protecting still-intact areas, noting frozen or desert patches are not the most abundant with species. “Encouraging nations to protect remote, sparsely populated areas won’t do biodiversity a lot of good,” Pimm said.

An effort led by the United Nations to protect 30% of the planet’s land and waters by 2030 — up from about 17% currently under some form of protection — has gained momentum over the last year, as governments including the United States have pledged to commit more land to conservation.

Some conservationists argue, however, that the world’s conservation goal should be much higher than 30% in order to prevent mass die-offs of species. A 2019 U.N. report estimated as many as 1 million species are under threat of extinction due to human activity. “30 by 30 is a nice catchphrase, but it won’t do much good if the areas to be protected are not selected carefully,” Pimm said.

If one Tyrannosaurus rex — the school bus-sized meat-eating dinosaur that stalked the Cretaceous Period landscape — seems impressive, how about 2.5 billion of them?

Researchers on Thursday unveiled the first calculation of the total T. rex population during the estimated 2.4 million years that this fearsome species inhabited western North America during the twilight of the age of dinosaurs.

They considered factors including the size of its geographic range, its body mass, growth pattern, age at sexual maturity, life expectancy, duration of a single generation and the total time that T. rex existed before extinction 66 million years ago. They also heeded a doctrine called Damuth's law linking population to body mass: the bigger the animal, the fewer the individuals.

Their analysis put the total number of T. rex individuals that ever existed at about 2.5 billion, including approximately 20,000 adults alive at any one time.

Fossils of more than 40 T. rex individuals have been found since it was first described in 1905, providing a wealth of information about a beast that thrives in the popular imagination.

"Why iconic?" asked paleontologist Charles Marshall, who led the study published in the journal Science. "Heck, a hugely massive killer with super-huge teeth, one that you would never dream up on your own if we didn't have the fossil record. So not only super-cool and beyond the imagination, but real. Like Godzilla, but actually real. And I think we like feeling small, and T. rex sure makes us feel small and vulnerable."

It was among the largest carnivorous dinosaurs, possessing a skull about 5 feet (1.5 meters) long, massive and muscular jaws with a bite force capable of crushing bone, a mouthful of banana-sized serrated teeth, a keen sense of smell, strong legs and puny arms with hands boasting just two fingers.

Perhaps the largest-known T. rex is a specimen named Sue at the Field Museum in Chicago, measuring 40-1/2-foot-long (12.3-meters), weighing an estimated 9 tons and living about 33 years.

The new study put the weight of the average adult T. rex at 5.2 tons, average lifespan at 28 years, generation time at 19 years, total number of generations of the species at about 125,000, and its geographic range at roughly 890,000 square miles (2.3 million square kilometers).

They calculated an average population density of about one T. rex for every roughly 40 square miles (100 square kilometers).

T. rex fossils have been found in Canada's Alberta and Saskatchewan provinces and the U.S. states of Montana, Wyoming, South Dakota, North Dakota, Utah, Colorado, New Mexico and Texas. T. rex apparently met a fiery end when an asteroid slammed into Mexico, exterminating three quarters of Earth's species.

While the uncertainties in the estimates were large and some of the assumptions may be challenged by other paleontologists, the study was a worthwhile effort to expand the understanding of this famous dinosaur, said Marshall, director of the University of California Museum of Paleontology and a University of California, Berkeley professor of integrative biology. The formula could be applied to other extinct animals, Marshall added.

Paleontologist and study co-author Ashley Poust of the San Diego Natural History Museum said while 2.5 billion is a lot, it represents only about a third of Earth's current human population — and 20,000 is merely the size of a small town.

“They’d have to meet up over possibly long distances to mate, or maybe even care for their young,” Poust said of Tyrannosaurus. “The numbers can seem big and cold, but I guess I see them as a pretty intimate window into their lives.”

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A recycled SpaceX capsule carrying four astronauts arrived at the International Space Station on Saturday.

The Dragon capsule docked autonomously with the orbiting outpost 420 kilometres above the Indian Ocean, a day after launching from NASA’s Kennedy Space Center.

The new arrivals – representing the U.S., France and Japan – will spend six months at the space station. They’ll replace four astronauts who will return to Earth in their own Dragon capsule Wednesday.

It was the first time two SpaceX crew Dragons were parked there at the same time – practically side by side.

Third crew flight

Although this was SpaceX’s third crew flight for NASA, it was the first to use a vehicle that’s flown before. The Dragon capsule was used for Space’'s first crew launch last May, while the Falcon rocket soaring Friday hoisted crew two in November.

Fully automated

NASA astronauts Shane Kimbrough and Megan McArthur – the commander and pilot of the arriving Dragon – monitored their capsule’s flat screen computers as the space station loomed ever larger. They could have taken control if necessary, but the autonomous system did its job, much like a self-driving car.

Also checking into the space station: France’s Thomas Pesquet and Japan's Akihiko Hoshide. Both have lived there before, as has Kimbrough. It was the first station visit for Megan McArthur.

For the next four days, the space station will be home to 11 astronauts, just shy of the record of 13 set during NASA's space shuttle era.

The Indian programme to study the Sun and the region between the Sun and the Earth from space – Aditya-L1 – is due to be launched next year. It will carry seven payloads which have been developed by various institutions across the country. Once the mission is launched, there will be a need for a ground support centre to monitor and coordinate the work on its various payloads. This role will be played by the ARIES facility (short for Aryabhata Research Institute for observational Sciences) which is situated near Nainital. In January 2021, an agreement was signed to this effect based on the proposal submitted by the ARIES team, led by Dipankar Banerjee, Director of ARIES, who is a solar physicist and co-chair of the science working group of the Aditya-L1 mission. With about four to five personnel, this centre will come up at Haldawani, where ARIES is setting up a data centre also.

Guest users

Researchers who may not even be associated with core Aditya-L1 team will be able to book a specific payload to conduct observations for a particular time. Any PhD student or postdoctoral fellow in a research institution can submit observing proposals through the online proposal submission system. “The main aim of this centre is to let every researcher in India perform analysis over scientific data obtained from Aditya-L1. The total number of guest users will be from a few tens to a few hundreds,” says Prof. Banerjee. A time allocation committee comprising senior and expert scientists will evaluate proposals based on their merit and feasibility to decide the priority. “We are open to users outside India by giving hand-outs of data analysis during international meetings and online training in the later phase of the mission,” he adds.

Studying lower corona

The Aditya-L1 Support Centre (ASC) will provide training through regular workshops for the guest users. Apart from this, it will provide ready-to-use Python and Java apps for the satellite data and demos and handouts to facilitate the guest users. An ARIES team has recently developed an algorithm to study the accelerating solar eruptions in the lower corona called CMEs Identification in Inner Solar Corona (in short, CIISCO), where CME stands for coronal mass ejection. Prof. Banerjee explains how this will be put to use: “The centre will also provide source code for advanced data analysis. For example, it will provide the source code for CIISCO that we have developed in ARIES to detect accelerating CMEs in the solar atmosphere.”

The group has also developed several advanced image processing algorithms to detect fine-scale structures in the solar atmosphere. Such techniques are important to capture dynamics at different spatial and temporal scales. Prof. Banerjee gives an example of this: “While ISRO will provide raw and calibrated spectra of the solar atmosphere, at ASC we will further process the spectra to derive meaningful quantities such as intensity, Doppler velocities and line widths and provide these quantities to the scientific community.”

The facility will store co-aligned data from other observatories. That is, data taken at other wavelengths of observation than by Aditya-L1 and aligned in time and space so that they complement Aditya-L1 observations.

Long-term plans

The centre will host a compendium of the location and duration of different features on the solar surface such as coronal holes, prominences, flares, CMEs and sunspots. “We will employ automated methods to detect these features,” he says. Continuous monitoring of the location and duration of these features will help in monitoring the Earth directed CMEs and thereby, the space weather. “Also, it will help us to understand the long-term evolution of these features and underlying physical mechanisms responsible for this,” says Prof. Banerjee.

“This centre will expand the visibility of Aditya-L1 beyond India at the international level.

Also, it will expand its reach within India. It will allow every interested individual to be able to perform scientific analysis of the data,” he adds.

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Bearded dragon embryos can use two different sets of genes to become a female lizard — one activated by the sex chromosomes and the other activated by high temperatures during development (PLOS Genetics).

This so-called temperature-dependent sex determination was discovered in the 1960s. Now, for the first time the molecular details of how it happens have been found by scientists from the University of Canberra.

It is known that male bearded dragons have ZZ sex chromosomes, while females have ZW sex chromosomes. However, hot temperatures can override the ZZ sex chromosomes, causing a male lizard to develop as a female.

The researchers discovered that, initially, different sets of developmental genes are active in the two types of females, but that ultimately the pathways converge to produce ovaries, according to a release.

The findings support recent research proposing that ancient signalling processes inside the cell help translate high temperatures into a sex reversal.

This study is the first to show there are two ways to produce an ovary in the bearded dragon, revealing partially how temperature determines sex.

In a meeting held on March 24, the Subject Expert Committee of the India drug regulator permitted Bharat Biotech to carry out a phase-2 trial of Covaxin wherein a booster dose is to be administered six months after the second dose to further improve vaccine efficacy. Currently, two doses of Covaxin are administered 28 days apart.

In the phase-2 trial 380 participants were recruited in all and were split into two groups of 190 each to receive either 3 microgram or 6 microgram of the vaccine. With the SEC directing Bharat Biotech to conduct the booster dose study only in the cohort that received 6 microgram of the vaccine, the phase-2 booster dose trial will be limited to 190 participants.

The booster dose will be given six months after the second dose and the company has been directed to follow up the participants who get a booster dose for at least six months.

Virologist Dr. Jacob John, formerly with CMC Vellore, feels that providing a booster dose will be a good idea in increasing the duration of protection. “The immunological principle says that to make long-lived antibody secreting cells as well as long-lived memory T cells, the first and second dose should be given 28 days apart and the third dose should be given with a minimum gap of four months after the second dose and optimally five months after the second dose,” he says.

According to him, when only two doses of the vaccine are given with a gap of 28 days between doses, the immunity would last for about a year or so. “So if the disease is around for more than a year, then a booster dose is needed after a year if only two doses are given one month apart,” says Dr. John. “The reason being that the first dose is a priming dose while the second dose given 28 days later is partially priming and partially boosting. As a result, the boosting effect of the second dose is short-lived, which is about a year.”

Since Covaxin uses an inactivated virus platform, the virus does not multiply in the body and so the antigen level is maximum only for a day or two. In order to stimulate the immune system, a second dose is needed.

He warns that when the second dose is given less than 28 days after the first, no boosting effect is achieved, and when given after 28 days, the booster effect is only partial and will last for about a year. So a booster dose will be needed after a year if the disease is around.

“If the third dose is administered four–five months after the second dose, the immunological principle is that the immunity will be long-lived. This is because the antibody secreting cells will be treated specially by the body and will be taken into the bone marrow and will live for years and continue secreting antibodies,” Dr. John says.

North Arcot study

He recalls the North Arcot (in Tamil Nadu) Polio study of 1986–95 where the inactivated polio vaccine was tested as three doses under the government’s watch. As required by ICMR, the study compared oral polio vaccine (OPV) and the inactivated polio vaccine (IPV).

While the CDC recommends four doses, most countries use three doses of inactivated polio vaccine. In the beginning, three doses of inactivated polio vaccine were given, with the second and third doses given with one month gap. But even after three doses a booster was needed a year later.

But the second dose given with at least eight weeks gap after the first resulted in higher antibody levels and longer duration of protection. However, a booster dose is still required and so the third dose is given a year after the second dose.

In the North Arcot Polio study of 1986–1995, Dr. John and his team administered the first dose at 14 weeks and the second dose 22 weeks later. The third dose was administered at nine months of age. “Polio almost disappeared,” Dr. John vividly recalls. Despite the very encouraging results of the study, the government dumped inactivated polio vaccine and instead went ahead using oral polio vaccine to combat polio in the country. Unfortunately, even the results of the study were not published.

Drop in cases

But in 1998, Dr. John and three others included the critical data of the North Arcot Polio study in a paper in The Lancet. The paper dealing with district-level disease surveillance showed that increasing vaccine coverage both in private and public health facilities resulted in a substantial drop in the prevalence of vaccine-preventable diseases. In the case of polio, the drop was from 150 cases in private hospitals and 116 cases in government hospitals in 1989 to just 14 polio cases in private hospitals and five cases in government hospitals six years later in 1995. “The intervention was not to eradicate but to contain polio,” says Dr. John recalling the study.

Even in the case of the HPV vaccine, three doses were initially given, with the second dose given a month after the first and the third dose given at six months. “Scientists soon found that the second dose was irrelevant. If the gap between the first and second dose is more than five months then a third dose is not required,” he says. “Protection between the first and second dose is not good. But since there is no pandemic and we don’t need short-term protection, the second dose of HPV is generally administered six months later. If both short-term and long-term protection is needed then three doses at 0-1-6 months interval are needed for HPV.”

Scientists at Johnson & Johnson on April 16 refuted an assertion in a major medical journal that the design of their COVID-19 vaccine, which is similar to AstraZeneca’s, may explain why both have been linked to very rare brain blood clots in some vaccine recipients.

The U.S. earlier this week paused distribution of the J&J vaccine to investigate six cases of a rare brain blood clot known as cerebral venous sinus thrombosis (CVST), accompanied by a low blood platelet count, in U.S. women under age 50, out of about 7 million people who got the shot.

The blood clots in patients who received the J&J vaccine bear close resemblance to 169 cases in Europe reported with the AstraZeneca vaccine, out of 34 million doses administered there.

Both vaccines are based on a new technology that uses a modified version of adenoviruses, which cause the common cold, as vectors to ferry instructions to human cells. Several scientists have suggested the issue may be a “class effect” linked to this type of vaccine.

In a letter on Friday in The New England Journal ofMedicine, J&J scientists refuted a case report published earlier this week by Kate Lynn-Muir and colleagues at the University ofNebraska, who asserted that the rare blood clots “could be related to adenoviral vector vaccines.”

In an interview with Reuters on Thursday, Dr. Anthony Fauci,the top U.S. infectious disease expert and an adviser to the White House, said the fact that they are both adenovirus vector vaccines is a “pretty obvious clue” that the cases could be linked to the vector.

“Whether that is the reason, I can’t say for sure, but it certainly is something that raises suspicion,” Dr. Fauci said.

In the correspondence on April 16, Macaya Douoguih, a scientist with J&J’s Janssen vaccines division, and colleagues pointed out that the vectors used in its vaccine and the AstraZeneca shot are “substantially different” and that those differences could lead to “quite different biological effects.”

Specifically, they noted that the J&J vaccine uses a human adenovirus while the AstraZeneca vaccine uses a chimpanzee adenovirus. The vectors are also from different virologic families or species, and use different cell receptors to enter cells.

The J&J shot also includes mutations to stabilise the so-called spike protein portion of the coronavirus that the vaccine uses to produce an immune response, while the AstraZeneca vaccine does not.

“The vectors are very different,” said Dr. Dan Barouch of the Center for Virology and Vaccine Research at Harvard’s Beth Israel Deaconness Medical Center in Boston, who helped design the J&J vaccine.

“The implications of issues with one vector for the other one are not clear at this point,” he said in an interview earlier this week.

The J&J scientists said in the letter there was not enough evidence to say their vaccine caused the blood clots and they continue to work with health authorities to assess the data.

A panel of advisers to the U.S. Centers for Disease Control and Prevention are expected to meet on April 23 to determine whether the pause on use of the J&J vaccine can be lifted.

The Tiki Formation in Madhya Pradesh, a treasure trove of vertebrate fossils, has now yielded a new species and two genera of cynodonts, small rat-like animals that lived about 220 million years ago.

The researchers from the Indian Institute of Technology Kharagpur, used scanning electron microscopy to study about 10 teeth samples collected from the village of Tihki in Shahdol District, Madhya Pradesh.

Teeth trail

The teeth were studied for size, crown shape, structure of the cusps and compared with previously reported cynodonts. The results showed that they had found a new species, and they named it Rewaconodon indicus, indicating India, the country it was discovered from.

The team also identified two new genera from the area. The first was named Inditherium floris, after India and the Latin word therium meaning beast. As the teeth had a flower-shaped crown, it earned the species name floris. The second was named Tikiodon cromptoni, after Tiki Formation and Greek word odon meaning tooth. The species name is after paleontologist A.W. Crompton.

Evolutionary link

Sanghamitra Ray, the corresponding author of the work, explains: “Cynodonts are important in evolutionary studies as this group ultimately gave rise to the present-day mammals. By studying their molar and premolar teeth, we see how they slowly evolved and modified. Their crown shape shows that these animals are actually intermediate forms that are very near to the mammalian line of evolution.” She is from the Department of Geology and Geophysics at the Indian Institute of Technology, Kharagpur.

Advait M. Jukar from the Department of Paleobiology at the National Museum of Natural History, Smithsonian Institution, who was not involved in the work explains some more: “Cynodonts and living mammals both belong to a group of egg-laying vertebrates (amniotes) called synapsids. The close relationship of cynodonts with living mammals is seen in their bones. They also have differentiated teeth ( for example, different teeth in the front of mouths compared with the back), a secondary palate in their mouths, which, like humans, allowed them to breathe and eat at the same time. Some cynodonts show evidence for the inferred presence of whiskers and fur.”

DNA analysis

When asked if DNA studies can be done on these teeth Dr. Ray explained that as the samples are extremely old, the organic matter would have completely degraded making it impossible to look at DNA.

About eighty cynodont genera have been reported from around the world. The ones similar to the newly discovered ones were previously found in Laurasia which includes North America, England, Germany, Switzerland, France, and Belgium. “This possibly suggests abiotic interchange between India and Laurasian regions and/or similarity in paleoclimatic conditions, but this requires further study,” according to the paper, which is recently published in the Journal of Paleontology.

Space agencies of India and France on Thursday signed an agreement for cooperation for the country's first human space mission Gaganyaan, the French space agency CNES said.

The agreement was announced during French Foreign Affairs minister Jean-Yves Le Drian visit to the Indian Space Research Organisation's (ISRO) headquarters.

ISRO has asked CNES to help prepare for Gaganyaan missions and to serve as its single European contact in this domain.

"Under the terms of the agreement, CNES will train India's flight physicians and CAPCOM mission control teams in France at the CADMOS centre for the development of microgravity applications and space operations at CNES in Toulouse and at the European Astronaut Centre (EAC) in Cologne, Germany," the CNES said.

The agreement provides for the CNES to support implementation of a scientific experiment plan on validation missions, exchange information on food packaging and the nutrition programme, and above all the use by Indian astronauts of French equipment, consumables and medical instruments.

French equipment developed by CNES, tested and still operating aboard the International Space Station (ISS) will thus be made available to Indian crews.

Thomas Pesquet, who is set to make his second flight to the International Space Station on April 22 for the Alpha mission, had previously tested these devices on his first spaceflight.

The CNES will also be supplying fireproof carry bags made in France to shield equipment from shocks and radiation, it said.

"This cooperation could be extended in the future to parabolic flights operated by Novespace to test instruments and for astronaut training, as well as technical support for construction of an astronaut training centre in Bangalore," the CNES added.

The Gaganyaan orbital spacecraft project was kicked off in August 2018. It originally intended to send astronauts from Indian soil to mark the 75th anniversary of India's independence in 2022.

However, the mission has been delayed due to the restrictions imposed in view of the coronavirus pandemic.

Among COVID-19 patients, a lack of exercise is linked to more severe symptoms and a higher risk of death, according to a study covering nearly 50,000 people who were infected with the virus.

People physically inactive for at least two years before the pandemic were more likely to be hospitalised, to require intensive care, and to die, researchers reported on Tuesday in the British Journal of Sports Medicine.

As a risk factor for serious COVID-19 disease, physical inactivity was surpassed only by advanced age and a history of organ transplant, the study found.

Indeed, compared to other modifiable risk factors such as smoking, obesity or hypertension, “physical inactivity was the strongest risk factor across all outcomes,” the authors concluded.

The pre-existing conditions most associated with severe COVID-19 infection are advanced age, being male, and having diabetes, obesity or cardiovascular disease.

But up to now, a sedentary lifestyle has not been included.

To see whether a lack of exercise increases the odds of severe infection, hospitalisation, admission into an intensive care unit (ICU), and death, the researchers compared these outcomes in 48,440 adults in the United States infected with COVID-19 between January and October 2020.

The average age of patients was 47, and three out of five were women. On average, their mass-body index was 31, just above the threshold for obesity.

Intensive care

Around half had no underlying illnesses, such as diabetes, chronic lung conditions, heart or kidney disease, or cancer. Nearly 20% had one, and more than 30% had two or more.

All of the patients had reported their level of regular physical activity at least three times between March 2018 and March 2020 at outpatient clinics.

Some 15% described themselves as inactive (0-10 minutes of physical activity per week), nearly 80% reported “some activity” (11-149 minutes/week), and 7% were consistently active in keeping with national health guidelines (150+ minutes/week).

After allowing for differences due to race, age and underlying medical conditions, sedentary COVID-19 patients were more than twice as likely to be admitted to hospital as those who were most active.

They were also 73% more likely to require intensive care, and 2.5 times more likely to die due to the infection.

Compared to patients in the habit of doing occasional physical activity, couch potatoes were 20% more likely to be admitted to hospital, 10% more likely to require intensive care, and 32% more likely to die.

While the link is statistically strong, the study — which is observational, as opposed to a clinical trial — cannot be construed as direct evidence that a lack of exercise directly caused the difference in outcomes.

The findings also depend on self-reporting by patients, with a potential for bias.

A study carried out by researchers from the Central University of Kerala has found that the monsoon was much stronger 7,000 years to 5,000 years ago and it underwent a cyclic change caused by variations in solar radiation.

A.V. Sijinkumar, Assistant Professor, Department of Geology, who led the research team, said the study was carried out in the Indian Ocean to understand changes in the monsoon in the past. This would help researchers forecast monsoon variability and the results could be used for building models that would offer insight into future variations in the monsoon, especially in the context of global warming.

“The monsoon is critical to Indian economy. A weak monsoon has led to severe droughts, famine, affecting the economy and food security, whereas a strong monsoon may lead to floods like those in Kerala in 2018 and 2019,” he said.

Mr. Sijinkumar said the main finding of the report was that the monsoon started weakening 4,200 to 2,000 years ago, before arriving at the present condition. The study found a strong summer monsoon in approximately every 10,000 years in the last 55,000 years.

Long-term records

He said the researchers looked for monsoon details in geological records because instrumental records (rain gauge data) were available only for the past 150 years. To improve forecasting, it was necessary to have long-term rainfall records, he said. “We have reconstructed monsoon variability by using the marine sediment core collected from the Andaman Sea. The Andaman Sea was selected because of its excellent preservation of fossils and the significant influence of river water run-off,” he said.

Mr. Sijinkumar said the sample fossil shells were dated using the radiocarbon dating technique. The study covered the time span of the past 55,000 years with a time resolution of 200 to 400 years. The microfossil shells, which look like sand grains to the naked eye, but were shaped in spirals, disks, spheres, tubes, and cones under microscope, were picked, identified, and their abundance recorded in each sample.

The isotopic and chemical composition of each samples was measured. The analyses gave the temperature and salinity of seawater at the time when foraminifera, a single cell organism, was alive. They tell about past freshwater runoff levels in the ocean from rivers. Less saline conditions indicate times of increased rainfall.

The results of the study were published in the Journal of Quaternary Science.

NASA has delayed by at least several days the first flight of its mini-helicopter on Mars after a possible tech issue emerged while testing its rotors, the U.S. space agency said Saturday.

Ingenuity's trip, which is to be the first-ever powered, controlled flight on another planet, was set for Sunday but is now on hold until at least April 14.

A high-speed test of the 1.8 kilogram helicopter's rotors on Friday ended earlier than expected due to an alert of a potential issue.

"The helicopter team is reviewing telemetry to diagnose and understand the issue," NASA said in a statement. "Following that, they will reschedule the full-speed test." NASA noted the copter is "safe and healthy" and had sent information back to Earth.

Initially the plan for Sunday was to have Ingenuity fly for 30 seconds to take a picture of the Perseverance rover, which touched down on Mars on February 18 with the helicopter attached to its underside.

NASA calls the unprecedented helicopter operation highly risky, but says it could reap invaluable data about the conditions on Mars.

The flight is a true challenge because the air on Mars is so thin — less than one percent of the pressure of Earth's atmosphere. This means Ingenuity must spin its rotor blades much faster than a helicopter needs to do on Earth in order to fly.

After the flight, Ingenuity will send Perseverance technical data on what it has done, and that information will be transmitted back to Earth. This will include a black and white photo of the Martian surface that Ingenuity is programmed to snap while flying.

A day later, once its batteries have charged up again, Ingenuity is to transmit another photo — in colour, of the Martian horizon, taken with a different camera.

If the flight is a success, NASA plans another no more than four days later. It plans as many as five altogether, each successively more difficult, over the course of a month.

NASA hopes to make the helicopter rise five meters (16 feet) and then move laterally.

The mission is be the equivalent on Mars of the first powered flight on Earth — by the Wright brothers in 1903 in Kitty Hawk, North Carolina. A piece of fabric from that plane has been tucked inside Ingenuity in honor of that feat.

Legend has it that during the height of the space race in the 1960s, NASA scientists figured that pens could not function in space. So, they spent millions of dollars developing a pen that could write in space, while their Soviet counterparts used the humble pencil.

This story has been floating around the Internet for way too long. However, it is just a myth.

The truth

According to NASA historians, NASA astronauts also used pencils. In 1965, NASA ordered 34 mechanical pencils from Houston's Tycam Engineering Manufacturing, Inc. at the rate of $128.89 per pencil. When the public got to know about these rates, there was an outcry, and NASA had to find something much cheaper for its astronauts to use.

The pencil loses out

The pencil wasn’t an ideal choice for writing in space because its tip could flake and break off, drifting in microgravity with the potential to harm an astronaut or an equipment. Apart from this, pencils are flammable, and NASA wanted to avoid anything flammable aboard a spacecraft.

And the pen?

Regular pens that work on Earth did not work in space because they rely on gravity for the flow of ink to the nib. This was understood quite early by scientists and hence astronauts used pencils. But with both the pencil and the pen creating issues, what did NASA finally resort to?

The saviour

Around the time NASA was embroiled in the mechanical pencils controversy, Paul C. Fisher of the Fisher Pen Co. designed a ballpoint pen that could work in space. His company invested one million dollars to fund, design, and patent the pen on its own.

Fisher’s pen operated seamlessly, not just in space, but also in a weightless environment, underwater, in other liquids, and in temperatures ranging from -50 F to +400 F.

The company offered the pen to NASA, but the space agency was hesitant to buy it due to the mechanical pencil controversy.

However, a few years later, after rigorous testing, NASA agreed to equip its astronauts with the space pen. The space agency bought 400 pens from Fisher. And a year later, the Russians also ordered 100 pens and 1,000 ink cartridges to use on their Soyuz space missions. Both NASA and the Soviet space agency received a 40% discount on bulk purchase of the pens, paying about $2.39 per pen.

Over the years, Fisher’s company has created different space pens, which are still used by NASA and the Soviet space agency.

If you would like to get your hands on one of these space pens, it would cost you approximately $50.

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A major milestone in evolutionary history occurred about 370 million years ago – the water-to-land transition – when a certain fish species converted its fins to limbs and modified its respiratory organ for air-breathing. So how did the creatures breathe when in water? A new study (Science Advances) has found evidence of advanced breathing organs in 450-million-year-old sea creatures called Trilobites.

Fossil studies showed that trilobites used gill-like structures hanging off their thighs to breathe. This went unnoticed for decades as scientists thought the upper branch of the leg was non-respiratory just like the upper branch seen in present-day crustaceans.

Advanced Computer tomography or CT scanner helped read the fossil and surrounding rock and 3D models of the gill structures were created. Paleontologist Melanie Hopkins, a research team member at the American Museum of Natural History explained in a release that the new technique helped get a view that would even be hard to see under a microscope. The gill structures were just 10 to 30 microns wide. For comparison, a human hair is about 100 microns thick.

The researchers write that blood would have filtered through chambers in these tiny structures and helped pick up oxygen. They note that this ancient gill is similar to those found in present-day crabs and lobsters.

“What’s in a name? A rose by any other name would smell as sweet,” wrote Shakespeare. But ask a taxonomist and she will tell you how naming plays an important role in understanding and organising the diverse life forms on our planet. Now, a new study has once again shown the importance of taxonomic classification. Detailed analysis of South Asian river dolphins has revealed that the Indus and Ganges River dolphins are not one, but two separate species.

Divergent species

Currently, they are classified as two subspecies under Platanista gangetica and this needs a revision. The study estimates that Indus and Ganges river dolphins may have diverged around 550,000 years ago.

The international team studied body growth, skull morphology, tooth counts, colouration and genetic makeup and published the findings last month in Marine Mammal Science.

DNA analysis

The corresponding author of the study Gill T. Braulik from the University of St. Andrews, U.K. explains about the DNA analysis to The Hindu: “To collect mitochondrial DNA, one would normally use skin samples or blood and hair. But in this instance, we didn’t really have access to fresh tissue samples. So we got ancient DNA out of skulls and skeletons, which were 20 to 30 to even 150 years old. Looking at the sequences in the DNA, it was quite clear that the Ganges dolphins and the Indus dolphins were quite different.”

The paper notes that “comparative studies of animals in the two river systems are complicated by the fact that they occur in neighboring countries separated by an unfriendly international border...Thus, sharing of samples or data between countries is extremely challenging.”

One of the authors of the paper Ravindra K. Sinha from Patna University explains: “The Ganges dolphin is a Schedule I animal under the Indian Wildlife (Protection) Act 1972, and has been included in Annexure – I of Convention on International Trade in Endangered Species (CITES), so you cannot transfer any tissue or sample to foreign countries without getting CITES permission from the Competent Authority of Government of India.” Another reason was that finding dead animals were uncommon because they either float downstream or sink, and museum collections worldwide contain only a few specimens and most of them are damaged.

Conservation status

The Indus and Ganges River dolphins are both classified as ‘Endangered’ species by the International Union for Conservation of Nature (IUCN). Dr. Sinha who has been studying Ganges dolphins for almost four decades explains that physical barriers such as dams and barrages created across the river reduced the gene flow to a great extent making the species vulnerable; He adds that river flow is also declining very fast as river water is being diverted through the barrages and this has affected the dolphin habitats. “Previously fishermen used to hunt dolphins and use their oil as bait, but though that practice of directed killing has stopped and they are not being hunted intentionally they end up as accidental catches. Also, before the 1990s, we had oar boats and country boats; but now mechanised boats are also causing accidental injury to the dolphins.”

Sources of pollution

Being a part of the Ganga Action Plan, Dr. Sinha monitored a large stretch of the river and noted that both point and non-point sources of pollution are affecting the dolphin habitat. “Recently we saw the Chinese river dolphin go extinct. Though the Indian government has given legal protection to the dolphin, more ground action and close work with local communities are needed to help them survive,” adds Dr. Sinha.

A fossil of a skunk-like mammal that lived during the age of dinosaurs has been discovered in Chilean Patagonia, adding further proof to recent evidence that mammals roamed that part of South America a lot earlier than previously thought.

A part of the creature’s fossilized jawbone with five teeth attached were discovered close to the famous Torres del Paine national park.

Christened Orretherium tzen, meaning ‘Beast of Five Teeth’ in an amalgam of Greek and a local indigenous language, the animal is thought to have lived between 72 and 74 million years ago during the Upper Cretaceous period, at the end of the Mesozoic era, and been a herbivore.

Prior to its discovery, and the teeth of the Magallanodon baikashkenke, a rodent-like creature, in the same area last year, only mammals living between 38 and 46 million years ago had been found in the southernmost tip of the Americas, the team that discovered it said.

The finds are critical to completing the evolutionary puzzle of the Gondwanatheria, a group of long-extinct early mammals that co-existed with dinosaurs, said Sergio Soto, a University of Chile paleontologist.

“This and other discoveries that we are going to make known in the future are revealing that there is enormous potential in terms of paleontology in the southern tip of Chile,” said Soto. “We are finding things that we did not expect to find and that are going to help us answer a lot of questions that we had for a long time about dinosaurs, mammals and other groups.”

The discovery was published in the journal Scientific Reports by experts from the University of Chile working with researchers from Argentina’s Natural History and La Plata museums and the Chilean Antarctic Institute.

The scientists think Orretherium tzen cohabited with Magallanodon baikashkenke, which was thought to have been an evolutionary step between a platypus or marsupial, and dinosaurs such as the long-necked titanosaur.

A Russian-U.S. trio of space travelers launched successfully Friday, heading for the International Space Station.

NASA astronaut Mark Vande Hei and Russian cosmonauts Oleg Novitskiy and Pyotr Dubrov blasted off as scheduled at 12:42 p.m. (0742 GMT, 3:42 a.m. EDT) aboard the Soyuz MS-18 spacecraft from the Russia-leased Baikonur launch facility in Kazakhstan.

They are set to dock at the station after a two-orbit, three-hour journey.

It’s the second space mission for Vande Hei and the third for Novitskiy, while Dubrov is on his first mission.

During their mission, the crew will work on hundreds of experiments in biology, biotechnology, physical science and Earth science.

Over a third of the Antarctic's ice shelf area may be at risk of collapsing into the sea if global temperatures reach four degrees Celsius above pre-industrial levels, according to a study.

The research, published in the Geophysical Research Letters journal, found that 34 % of the area of all Antarctic ice shelves – around half a million square kilometers – including 67 % of ice shelf area on the Antarctic Peninsula, would be at risk of destabilisation under such a warming scenario.

The team also identified Larsen C – the largest remaining ice shelf on the peninsula, which split to form the enormous A68 iceberg in 2017 – as one of four ice shelves that would be particularly threatened in a warmer climate.

"Ice shelves are important buffers preventing glaciers on land from flowing freely into the ocean and contributing to sea level rise," said Ella Gilbert from the University of Reading in the UK.

"When they collapse, it's like a giant cork being removed from a bottle, allowing unimaginable amounts of water from glaciers to pour into the sea," Ms. Gilbert said.

The researchers noted that limiting temperature rise to two degrees Celsius rather than four degrees Celsius would halve the area at risk, and potentially avoid significant sea level rise.

They noted that when melted ice accumulates on the surface of ice shelves, it can make them fracture and collapse spectacularly.

Previous research has given the scientists the bigger picture in terms of predicting Antarctic ice shelf decline.

However, the new study uses the latest modelling techniques to fill in the finer detail and provide more precise projections.

"The findings highlight the importance of limiting global temperature increases as set out in the Paris Agreement if we are to avoid the worst consequences of climate change, including sea level rise," said Ms. Gilbert.

The study used state-of-the-art, high-resolution regional climate modelling to predict in more detail than before the impact of increased melting and water runoff on ice shelf stability.

The team said the ice shelf vulnerability from this fracturing process was forecast under 1.5, 2 and 4 degrees Celsius global warming scenarios, which are all possible this century.

Ice shelves are permanent floating platforms of ice attached to areas of the coastline and are formed where glaciers flowing off the land meet the sea, they said.

The researchers identified the Larsen C, Shackleton, Pine Island and Wilkins ice shelves as most at-risk under four degrees Celsius of warming, due to their geography and the significant runoff predicted in those areas.

"If temperatures continue to rise at current rates, we may lose more Antarctic ice shelves in the coming decades," Ms. Gilbert added.

Fermilab, which houses the American particle accelerator, has released the first results from its ‘muon g-2’ experiment. These results spotlight the anomalous behaviour of the elementary particle called the muon. The muon, a heavier cousin of the electron, is expected to have a value of 2 for its magnetic moment, labelled ‘g’. However, the muon exists not in isolation but embedded in a sea where particles are popping out and vanishing every instant due to quantum effects. So, its g value is altered by its interactions with these short-lived excitations.

Magnetic moment

The Standard Model of particle physics calculates this correction, called the anomalous magnetic moment, very accurately.

The muon g-2 experiment measured the extent of the anomaly and on Wednesday, Fermilab announced that the measured ‘g’ deviated from the amount predicted by the Standard Model. That is, while the calculated value in the Standard Model is 2.00233183620 approximately, the experimental results show a value of 2.00233184122.

When the results are combined with those from a 20-year-old experiment at Brookhaven National Laboratory in the U.S., they show an accuracy of about 4.2 sigma. This means the possibility that this is due to a statistical fluctuation is about 1 in 40,000. This makes physicists sit up and take note, but it is not significant enough to constitute a discovery, for which a significance of 5 sigma is needed.

It is interesting that while the Brookhaven experiment had to be closed down in 2001, the main component of the experimental set up, a large superconducting magnetic storage ring that measures over 15 metres in diameter, was transported a distance of over 5,000 kilometres, in 2013, to be reused in the Fermilab experiment.

Rahul Sinha of The Institute of Mathematical Sciences, Chennai, who specialises in studying physics beyond the Standard Model, is very excited by the Fermilab result. According to him, even though the experiment measures a very elementary property related to the magnetic moment of the muon it is by no means a simple experiment. “Kudos to the experimental team for such a detailed treatment of the mindboggling systematic effects that makes this measurement so special. The muon g-2 experiment at Fermilab promises to be a torch bearer in the search for new physics,” he says.

The g factor

The muon is also known as the ‘fat electron’. It is produced copiously in the Fermilab experiments and occurs naturally in cosmic ray showers. Like the electron, the muon has a magnetic moment because of which, when it is placed in a magnetic field, it spins and precesses, or wobbles slightly, like the axis of a spinning top. Its internal magnetic moment, the g factor, determines the extent of this wobble.

As the muon spins, it also interacts with the surrounding environment, which consists of short-lived particles popping in and out of a vacuum.

The implications of this difference in the muon’s g factor can be significant. The Standard Model is supposed to contain the effects of all known particles and forces at the particle level. So, a contradiction of the Standard Model would imply that there exist new particles, and their interactions with known particles would enlarge the canvas of particle physics. These new particles could be the dark matter particles which people have been looking out for, in a long time. These interactions make corrections to the g factor, and this affects the precession of the muon.

Thus, if the measured g factor differs from the value calculated by the Standard Model, it could signify that there are new particles in the environment that the SM does not account for. “This observation together with the recently observed anomaly in B decays at CERN indicates that the effects of new yet unobserved particles and forces is being seen as quantum effects,” says Prof. Sinha.

Note of caution

There have also been calculations made by a group of scientists which appeared in Nature that use the Standard Model itself to explain this difference. But these so-called Lattice Models could have large errors and need to be substantiated further.

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Scientists from Singapore are closely working on ‘robo-plants’, an experiment they call a fusion of nature and technology. They attached electrodes to a Venus flytrap plant.

The electrodes are film-like and soft and fit tightly to the plant's surface. They are attached using a ‘thermogel’, which is liquid at low temperatures but turns into a gel at room temperature. These electrodes are capable of monitoring weak electrical pulses naturally emitted by plants.

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DNA extracted from remains found in a Bulgarian cave of three people who lived roughly 45,000 years ago is revealing surprises about some of the first Homo sapiens populations to venture into Europe, including extensive interbreeding with Neanderthals and genetic links to present-day East Asians.

Scientists said on Wednesday they sequenced the genomes of these three individuals — all males — using DNA obtained from a molar and bone fragments discovered in Bacho Kiro Cave near the town of Dryanovo, as well as one female who lived roughly 35,000 years ago at the same site.

Also read: DNA reveals first inter-species child

Our species first appeared in Africa approximately 300,000 years ago and later trekked to other parts of the world, sometimes encountering Neanderthals — our close cousins — already inhabiting parts of Eurasia. The three Bacho Kiro Cave males represent the oldest securely dated Homo sapiens individuals from Europe.

They had 3% to 3.8% Neanderthal DNA, and had Neanderthal ancestors about five to seven generations back in their family histories, evidence of interbreeding, said geneticist Mateja Hajdinjak of the Francis Crick Institute in London, lead author of the study published in the journal Nature.

Interbreeding, known as admixture, between Homo sapiens and Neanderthals before the extinction of Neanderthals sometime after 40,000 years ago has been previously shown, with present-day human populations outside Africa bearing a small percentage of Neanderthal DNA.

The prevalence of this interbreeding and the relationship and power dynamics between Homo sapiens and Neanderthals has been harder to understand — including any role our species played in the demise of the Neanderthals. The new study suggests interbreeding was more common than previously known for the first Homo sapiens in Europe.

It is an “amazing observation” that all three individuals had Neanderthal ancestors in their recent family history, said geneticist and study co-author Svante Pääbo, director of the Max Planck Institute for Evolutionary Anthropology in Germany.

“This makes it likely that the earliest modern humans frequently mixed with Neanderthals when they met. It may even be the case that part of the reason Neanderthals disappeared is that they were simply absorbed into larger modern human groups. It may be just part of the reason they disappeared but the data supports such a scenario,” Pääbo said.

The researchers detected a genetic contribution among present-day people from the group that included these three, but unexpectedly it was found particularly in East Asia, including China, rather than Europe. This suggested that some people from this group eventually headed east.

“This study shifted our previous understanding of early human migrations into Europe in a way that it showed how even the earliest history of modern humans in Europe may have been tumultuous and involved population replacements,” Hajdinjak said.

The notion of population replacement was illustrated by the fact that the 35,000-year-old individual from Bacho Kiro Cave belonged to a group genetically unrelated to the site’s earlier inhabitants.

Another study published on Wednesday in the journal Nature Ecology & Evolution shed more light on Europe’s early Homo sapiens populations.

Scientists sequenced the genome of a Homo sapiens female using DNA extracted from a skull found at a site southwest of Prague in the Czech Republic. She is believed to have lived more than 45,000 years ago, though radiocarbon dating efforts to determine a firm date were unsuccessful.

This woman carried 3% Neanderthal ancestry and bore genetic traits suggesting she had dark skin and dark eyes, said geneticist Kay Prüfer of the Max Planck Institute for Evolutionary Anthropology, the study’s lead author. “Her skull shows evidence of gnawing by a predator, possibly a hyena,” Prüfer said.

Her group, distinct from the one in Bulgaria, appears to have died out without leaving genetic ancestry among modern-day people.

Tu Youyou is a Chinese scientist, known for her isolation of the antimalarial substance artemisinin. She won the 2015 Nobel Prize for Physiology or Medicine (shared with Irish-born American parasitologist William Campbell and Japanese microbiologist Omura Satoshi).

Tu was born in Ningbo, Zhejiang, China, in 1930. A tuberculosis infection at 16 interrupted her education for two years, but inspired her to pursue medical research. In 1955, Tu graduated from Beijing Medical University School of Pharmacy and continued her research on Chinese herbal medicine in the China Academy of Chinese Medical Sciences. After graduation, Tu worked at the Academy of Traditional Chinese Medicine in Beijing.

In 1967, during the Vietnam War, North Vietnam requested China to help battle malaria, which was affecting its soldiers. Tu was appointed to lead Project 523, a secret effort to discover a treatment for malaria. Tu and her team pored over ancient Chinese medical texts to identify plants with appropriate medicinal value. Out of 640 plants identified, 380 extracts from about 200 plant species were zeroed in. The target was to rid malaria-causing Plasmodium parasites from the blood of infected people.

In 1971, after refining the extraction process, Tu and colleagues successfully isolated a nontoxic extract from sweet wormwood that effectively eliminated Plasmodium parasites from mice and monkeys. In 1972, they isolated the active compound in the extracts, which they named qinghaosu, or artemisinin. Tu and two colleagues tested the substance on themselves before testing them on 21 patients in the Hainan Province. All of them recovered.

Her work was not published in English until 1979. The World Health Organisation invited Tu to present her findings on the global stage in 1981. It took two decades, but finally the WHO recommended artemisinin combination therapy as the first line of defence against malaria.

In 2011 she received the Lasker-DeBakey Clinical Medical Research Award for her contributions to the discovery of artemisinin. When she won the Nobel in 2015, Tu became the first Chinese Nobel laureate in physiology or medicine and the first female citizen of the People's Republic of China to receive a Nobel Prize in any category.

A team of researchers from the Indian Institute of Technology-Guwahati (IIT-G) has developed a technique of boosting the performance of rechargeable lithium-ion batteries used in electric vehicles (EVs).

The advanced technique can precisely estimate the state of charge (SOC), one of the most important internal aspects of a battery, the team from the institute’s Department of Electronics and Electrical Engineering said.

The research by Professor Somanath Majhi, Associate Professor Sisir Kumar Nayak and research scholar Gautam Sethia was published in IEEE Transactions on Circuit and System I: Regular Papers, a scientific journal.

The SOC indicates the remaining charge that can be withdrawn from a battery before it gets fully discharged. “The knowledge of remaining capacity helps optimise a battery’s capacity utilisation, prevent its overcharging and undercharging, increase its lifespan, reduce cost, and ensure the safety of the battery and its surroundings,” Prof. Majhi said.

Lithium-ion batteries are preferred in cellphones and laptops for their low carbon emission, high energy density, low self-discharge rate, and low maintenance cost. They are also being widely used in EVs, integrated smart grids and microgrids of renewable energy sources.

“The EVs are becoming the most suitable alternatives to the conventional fossil fuel-based vehicles. The battery acts as the prime energy source of electric vehicles. The precise estimation of SOC that cannot be directly measured by any sensor plays a vital role for their efficient operation,” Prof. Majhi said.

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Light it up

Published in Science

Bose-Einstein condensate is a state of matter that occurs at extremely low temperatures. A new study has shown a previously unknown phase transition in the Bose-Einstein condensate. "The overdamped phase we observed corresponds to a new state of the light field, so to speak," says lead author Fahri Emre Öztürk in a release. The team writes that this can find applications in transmitting quantum-encrypted messages.

Ancient innovation

Published in Nature

About 105 thousand years ago, humans lived in coastal southern Africa as well as in the Kalahari basin about 600 km inland. A study on the collection of objects such as calcite crystals and ostrich eggshells from the Basin showed that the early humans who lived inland were as innovative as those who lived near the coast. The authors write that the shells may have been used for water storage and the crystals found a role in rituals.

Face vs brain shape

Published in Nature Genetics

By studying the various genes in our body, an international team has identified 76 overlapping genetic locations that shape both our face and our brain. But the team writes that this overlap is almost completely unrelated to that individual’s behavioural-cognitive traits. So it will be impossible to tell the risk of developing a neuropsychiatric disorder just by looking at a person’s face.

Cool physics

Published in Nature

Using special laser techniques, researchers from the European Organisation for Nuclear Research (CERN) have successfully shown the cooling of antimatter. “With this technique, we can address long-standing mysteries like: How does antimatter respond to gravity? Can antimatter help us understand symmetries in physics?. These answers may fundamentally alter our understanding of our Universe,” says Dr. Takamasa Momose, a physicist at the University of British Columbia and one of the authors of the paper in a release.

Antarctic meteor

Published in Science Advances

About 430 thousand years ago, an asteroid at least 100 m in size, burst on top of Antarctica says a new study. A study on seventeen spherules found on the summit of Walnumfjellet in the Sør Rondane Mountains helped the researchers tell this story. “This study has implications for the identification and inventory of large cosmic events on Earth,” adds the paper.

During some summers, as the Caribbean water temperatures climb, the luminous coral colonies of gold, green and blue that ring the island nation of Cuba give way to patches of skeletal white. The technicolor streaks of darting tropical fish flash less frequently. The rasping sounds of lobsters go quiet.

While Cuba’s marine life has suffered from overfishing and pollution, there is mounting evidence that the warming of waters due to climate change may be taking a large toll as well — both off the island’s coast and globally.

Research published Monday finds that the total number of open-water species declined by about half in the 40 years up to 2010 in tropical marine zones worldwide. During that time, sea surface temperatures in the tropics rose nearly 0.2℃.

“Climate change is already impacting marine species diversity distribution,” with changes being more dramatic in the Northern Hemisphere where waters have warmed faster, said study co-author Chhaya Chaudhary, a biogeographer at Goethe University.

While numerous factors like overfishing have impacted tropical species, the study published in the Proceedings of the National Academy of Sciences found a strong correlation between species decline and rising temperature. Fish species diversity tended to either plateau or decline at or above 20℃, the researchers found.

‘Blink of an eye’

While past studies have shown that ocean warming is driving some species to migrate to cooler waters, the new study attempts to gauge that impact more broadly — analyzing data on 48,661 marine species including fish, mollusks, birds and corals since 1955.

The dataset is a representative sample of 20% of all named open-water and seabed-dwelling marine species - like corals and sponges, researchers said.

The number of species attached to the seafloor remained somewhat stable in the tropics between the 1970s and 2010, according to the study. Some were also found beyond the tropics, suggesting they had expanded their ranges. In other words, scientists say, species that can move are moving.

“In geological history, this has occurred in the blink of an eye,” said Sebastian Ferse, an ecologist at the Leibniz Centre for Tropical Marine Research who was not involved with the study. “To see such changes occurring so rapidly is something quite alarming.”

For fixed species like corals, moving is not an option.

“One of the big questions is ‘Will coral reefs as ecosystems and corals as species be able to move north or south enough fast enough to adjust to a changing climate?’” Ferse said.

Having fleets of fish and other swimmers shift rapidly to more temperate waters could devastate the coral ecosystems they leave behind — along with any fishing and tourism industries that rely on them.

Such changes “can have a really huge impact on some of the most vulnerable human communities around the planet,” said Stuart Pimm, a conservation scientist at Duke University not involved in the study.

For Cuba, such an impact could unravel the island nation’s efforts to manage its underwater gardens although its corals have been less stressed by coastal development and pollution than corals elsewhere. They are considered more resilient to ocean warming.

“It’s impressive to return to an area that experienced significant bleaching the year before, but looks perfectly healthy a year later,” said Daniel Whittle, who heads the Caribbean program at the Environmental Defense Fund.

Cuba opened its first coral reef nursery four years ago to research which species coped best with warming and eventually to repopulate depleted reefs. The country is also restoring coastal mangroves, which serve as fish nurseries and shelter.

Chaudhary and her colleagues plan next to look at which tropical species were in decline or were migrating.

Prioritising who receives the limited supply of COVID-19 vaccines available can save lives and reduce the spread of the viral infection, according to a study.

Researchers from the University of California (UC), Davis in the U.S. noted that while there is mostly universal agreement that older people should be prioritised for vaccination, debates are currently underway about giving priority to a variety of other groups.

"Prioritisation has benefits because people differ in at least two key ways — their risk of infection and the likelihood of serious consequences from infection," said UC Davis professor Michael Springborn, senior author of the study published in the journal PNAS.

"We know that front-line essential workers have less capacity to socially distance and thus an elevated risk, while seniors are more seriously impacted by infection,” said Springborn, adding that accounting for this substantially increases the benefits of vaccination.

The researchers modelled COVID-19 transmission rates and the optimal allocation of an initially limited vaccine supply in the U.S. under a variety of scenarios.

They found that deaths, years of life lost and infections were between 17% and 44% lower when vaccinations targeted vulnerable populations — particularly seniors and essential workers — rather than an alternative approach where everyone is equally likely to be vaccinated.

"We also found that in regions where there was a faster increase in infections, and where there is less masking and social distancing occurring, targeting was even more important in avoiding those outcomes," said study lead author Jack Buckner, a PhD candidate in the UC Davis Graduate Group in Ecology.

The team identified that front-line essential workers should be a vaccination priority along with or shortly after seniors. The researchers noted that policies that target based on both age and essential worker status substantially outperformed those that consider age only. They said prioritising essential workers versus seniors depends on the conditions.

For example, the researchers explained when there is a good supply of effective vaccines and the outbreak is relatively under control, targeting essential workers first to help reduce overall spread can be ideal.

However, if vaccine supply is limited and cases and deaths are surging, targeting seniors and the most vulnerable directly may be the better strategy, they said. Previous studies have assumed that a given prioritisation strategy remains constant over time.

The latest study uniquely allows for prioritisation to evolve as conditions change, such as when more people in certain groups become vaccinated.

"There is a substantial value to prioritisation, at least for the first few months of the vaccine rollout," Springborn said.

"Once a large proportion of the most vulnerable people or the most likely to be exposed have been vaccinated, it becomes less important who gets it," Buckner added.

For the first time, researchers at the University of Leuven, Belgium have succeeded in measuring brain waves directly through ear implants. These brain waves indicate how good or bad a person’s hearing is.

"In our research, we have succeeded in using these implanted electrodes to record the brain waves that arise in response to sound. That is a first," said Ben Somers, postdoctoral researcher from the experimental Oto-rhino-laryngology unit in a release. He is the first author of the paper published last month in Scientific Reports.

Researchers expect this finding to help manufacturers further develop smart hearing aids. It can measure larger brain responses than the traditional electrodes planted on the head.

An ear implant enables people with severe hearing loss to hear again. An audiologist adjusts the device based on the user's input. However, children who are born deaf or elderly people with dementia have more difficulty assessing and communicating how well they hear the sounds, resulting in an implant that is not tuned to their situation.

Researchers believe that the new development can adjust the implant based on brain waves and help to get a measurement that does not depend on the user's input. They also expect that audiologists can consult the data remotely and adjust the implant where necessary, without the user going through testing at the hospital.

They believe that in the future, the hearing implant can adjust itself autonomously based on the recorded brain waves.

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NASA's Ingenuity mini-helicopter has been dropped on the surface of Mars in preparation for its first flight, the U.S. space agency said.

The ultra-light aircraft had been fixed to the belly of the Perseverance rover, which touched down on the Red Planet on February 18.

A photograph accompanying the tweet showed Perseverance had driven clear of the helicopter and its "airfield" after dropping to the surface.

Ingenuity had been feeding off the Perseverance's power system but will now have to use its own battery to run a vital heater to protect its unshielded electrical components from freezing and cracking during the bitter Martian night.

"This heater keeps the interior at about 45 degrees F (7 degrees Celsius) through the bitter cold of the Martian night, where temperatures can drop to as low as -130F (-90 degrees Celsius)," Bob Balaram, Mars Helicopter Project chief engineer at the Jet Propulsion Laboratory, wrote in an update on Friday. "That comfortably protects key components such as the battery and some of the sensitive electronics from harm at very cold temperatures."

Over the next couple of days, the Ingenuity team will check that the helicopter's solar panels are working properly and recharging its battery before testing its motors and sensors ahead of its first flight, Balaram said.

Ingenuity is expected to make its first flight attempt no earlier than April 11, the Jet Propulsion Laboratory tweeted.

Ingenuity will be attempting to fly in an atmosphere that is one percent the density of Earth's, which makes achieving lift harder — but will be assisted by gravity that is one-third of our planet's.

The first flight will involve climbing at a rate of about three feet (one meter) per second to a height of 10 feet (three meters), hovering there for 30 seconds, then descending back to the surface.

Ingenuity will be taking high-resolution photography as it flies. Up to five flights of gradual difficulty are planned over the month.

The 1.8-kilogram rotorcraft cost NASA around $85 million to develop and is considered a proof of concept that could revolutionize space exploration.

Future aircraft could cover ground much quicker than rovers, and explore more rugged terrain.

Scientists have identified three different types of COVID-19 disease traits in patients, depending on their comorbidities, complications, and clinical outcomes, an advance that may help target future interventions to the most risk-prone individuals.

The new study, published in the journal PLOS ONE, analysed the electronic health records (EHRs) from 14 hospitals in the midwestern U.S. and from 60 primary care clinics in the state of Minnesota.

According to the researchers, including those from the University of Minnesota in the U.S., the study included 7,538 patients with confirmed COVID-19 between March 7 and August 25, 2020, of which 1,022 patients required hospitalisation.

Close to 60% of the patients included in the research presented with what the researchers called "phenotype II." They said about 23% of the patients presented with "phenotype I," or the "adverse phenotype," which was associated with the worst clinical outcomes. The researchers said these patients had the highest level of comorbidies related to heart and kidney dysfunction.

According to the study, 173 patients, or 16.9 % presented with "phenotype III," or the "favorable phenotype," which the scientists said was associated with the best clinical outcomes. While this group had the lowest complication rate and mortality, the scientists said these patients had the highest rate of respiratory comorbidities as well as a 10% greater risk of hospital readmission compared to the other phenotypes.

Overall, they said phenotypes I and II were associated with 7.30-fold and 2.57-fold increases in hazard of death relative to phenotype III.

Based on the results, the scientists said such phenotype-specific medical care could improve COVID-19 outcomes. However, they believe further studies are needed to determine the utility of these findings in clinical practice.

"Patients do not suffer from COVID-19 in a uniform matter. By identifying similarly affected groups, we not only improve our understanding of the disease process, but this enables us to precisely target future interventions to the highest risk patients," the scientists added.

Two researchers from IIT Kanpur have developed a touch-sensitive, tactile, haptic watch that can help visually impaired people learn what time it is by touching the face. The watch makes up for two of the disadvantages of watches made for the use of visually challenged people: first, the lack of privacy in watches that audibly announce the time and second, the large sizes of touch sensitive watches.

The prototypes were developed by Siddhartha Panda, who is a professor at the Department of Chemical Engineering and the National Centre for Flexible Electronics at IIT Kanpur, and Vishwaraj Srivastava who is a Senior Project Associate at the Centre.

Telling time

The watch conveys the time in the form of vibrations when a person touches the right spoke on the face. For instance, if the time is 6.15, the watch gives a vibration of slightly long duration when the sixth spoke is touched and a short vibration when the third spoke is touched. “The watches have resolution of five minutes right now, but with an improvement we are planning, the resolution can go up to one minute,” says Mr Srivastava. They have filed for a patent for the watch.

Not just the simple watch, the researchers have also developed a prototype smart watch which can, in addition to telling the time, measure vital health parameters.

They started working on the watches only in September 2020 as a part of an older and longer project to develop a tool that would help a visually challenged person interface with a computer. “This was basically the low-hanging fruit,” says Prof. Panda, about the project. “The interface is more complicated and is in the process of being developed.”

The watch has been tested with the help of a person from IIT Kanpur who is visually challenged. They plan to have a more formal testing done soon.

The other project – a computer user-interface that is friendly to visually impaired users - is gaining ground. The device consists of a wearable headset or headband, to which is attached a camera eye, and a haptic glove. The word haptic refers to technology that enables transmission and reception of information through touch.

Virtual screen

By coupling the camera to the touch-sensitive glove, visually challenged users can be helped to navigate a virtual screen spread out before them. Further if this virtual screen is coupled to a smart phone or ATM, they can operate the same even if they are not able to see it. This device is still in the works.

Both Mr. Srivastava and Prof. Panda say that the projects are close to their hearts as they have been deeply affected by people close to them with visual impairment.

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NASA's Ingenuity mini-helicopter has been dropped on the surface of Mars in preparation for its first flight, the U.S. space agency said.

The ultra-light aircraft had been fixed to the belly of the Perseverance rover, which touched down on the Red Planet on February 18.

A photograph accompanying the tweet showed Perseverance had driven clear of the helicopter and its "airfield" after dropping to the surface.

Ingenuity had been feeding off the Perseverance's power system but will now have to use its own battery to run a vital heater to protect its unshielded electrical components from freezing and cracking during the bitter Martian night.

"This heater keeps the interior at about 45 degrees F (7 degrees Celsius) through the bitter cold of the Martian night, where temperatures can drop to as low as -130F (-90 degrees Celsius)," Bob Balaram, Mars Helicopter Project chief engineer at the Jet Propulsion Laboratory, wrote in an update on Friday. "That comfortably protects key components such as the battery and some of the sensitive electronics from harm at very cold temperatures."

Over the next couple of days, the Ingenuity team will check that the helicopter's solar panels are working properly and recharging its battery before testing its motors and sensors ahead of its first flight, Balaram said.

Ingenuity is expected to make its first flight attempt no earlier than April 11, the Jet Propulsion Laboratory tweeted.

Ingenuity will be attempting to fly in an atmosphere that is one percent the density of Earth's, which makes achieving lift harder — but will be assisted by gravity that is one-third of our planet's.

The first flight will involve climbing at a rate of about three feet (one meter) per second to a height of 10 feet (three meters), hovering there for 30 seconds, then descending back to the surface.

Ingenuity will be taking high-resolution photography as it flies. Up to five flights of gradual difficulty are planned over the month.

The 1.8-kilogram rotorcraft cost NASA around $85 million to develop and is considered a proof of concept that could revolutionize space exploration.

Future aircraft could cover ground much quicker than rovers, and explore more rugged terrain.

Scientists have identified three different types of COVID-19 disease traits in patients, depending on their comorbidities, complications, and clinical outcomes, an advance that may help target future interventions to the most risk-prone individuals.

The new study, published in the journal PLOS ONE, analysed the electronic health records (EHRs) from 14 hospitals in the midwestern U.S. and from 60 primary care clinics in the state of Minnesota.

According to the researchers, including those from the University of Minnesota in the U.S., the study included 7,538 patients with confirmed COVID-19 between March 7 and August 25, 2020, of which 1,022 patients required hospitalisation.

Close to 60% of the patients included in the research presented with what the researchers called "phenotype II." They said about 23% of the patients presented with "phenotype I," or the "adverse phenotype," which was associated with the worst clinical outcomes. The researchers said these patients had the highest level of comorbidies related to heart and kidney dysfunction.

According to the study, 173 patients, or 16.9 % presented with "phenotype III," or the "favorable phenotype," which the scientists said was associated with the best clinical outcomes. While this group had the lowest complication rate and mortality, the scientists said these patients had the highest rate of respiratory comorbidities as well as a 10% greater risk of hospital readmission compared to the other phenotypes.

Overall, they said phenotypes I and II were associated with 7.30-fold and 2.57-fold increases in hazard of death relative to phenotype III.

Based on the results, the scientists said such phenotype-specific medical care could improve COVID-19 outcomes. However, they believe further studies are needed to determine the utility of these findings in clinical practice.

"Patients do not suffer from COVID-19 in a uniform matter. By identifying similarly affected groups, we not only improve our understanding of the disease process, but this enables us to precisely target future interventions to the highest risk patients," the scientists added.

Two researchers from IIT Kanpur have developed a touch-sensitive, tactile, haptic watch that can help visually impaired people learn what time it is by touching the face. The watch makes up for two of the disadvantages of watches made for the use of visually challenged people: first, the lack of privacy in watches that audibly announce the time and second, the large sizes of touch sensitive watches.

The prototypes were developed by Siddhartha Panda, who is a professor at the Department of Chemical Engineering and the National Centre for Flexible Electronics at IIT Kanpur, and Vishwaraj Srivastava who is a Senior Project Associate at the Centre.

Telling time

The watch conveys the time in the form of vibrations when a person touches the right spoke on the face. For instance, if the time is 6.15, the watch gives a vibration of slightly long duration when the sixth spoke is touched and a short vibration when the third spoke is touched. “The watches have resolution of five minutes right now, but with an improvement we are planning, the resolution can go up to one minute,” says Mr Srivastava. They have filed for a patent for the watch.

Not just the simple watch, the researchers have also developed a prototype smart watch which can, in addition to telling the time, measure vital health parameters.

They started working on the watches only in September 2020 as a part of an older and longer project to develop a tool that would help a visually challenged person interface with a computer. “This was basically the low-hanging fruit,” says Prof. Panda, about the project. “The interface is more complicated and is in the process of being developed.”

The watch has been tested with the help of a person from IIT Kanpur who is visually challenged. They plan to have a more formal testing done soon.

The other project – a computer user-interface that is friendly to visually impaired users - is gaining ground. The device consists of a wearable headset or headband, to which is attached a camera eye, and a haptic glove. The word haptic refers to technology that enables transmission and reception of information through touch.

Virtual screen

By coupling the camera to the touch-sensitive glove, visually challenged users can be helped to navigate a virtual screen spread out before them. Further if this virtual screen is coupled to a smart phone or ATM, they can operate the same even if they are not able to see it. This device is still in the works.

Both Mr. Srivastava and Prof. Panda say that the projects are close to their hearts as they have been deeply affected by people close to them with visual impairment.

Researchers from India, the U.K. and Russia have analysed a large collection of 502 genomes sourced from over 16 countries and collected from over a period of 122 years of the bacterium that causes diphtheria – Corynebacterium diphtheriae. The results of this massive and collaborative study hint that we need to anticipate increase in incidence of diphtheria which may be fomented by the diversity of the species, emergence of variant toxin genes and progression of antimicrobial resistance.

They recommend that more in vivo and in vitro studies be undertaken to verify these hypotheses. The work was published recently in Nature Communications.

Diphtheria usually begins with angina (a type of chest pain) and tonsilitis symptoms, sore throat and mild fever. The diphtheria toxin causes inflammation of heart muscle (myocarditis) and this can lead to death if not treated with diptheria antitoxin and proper antibiotics. Formation of white-grey pseudomembrane over parts of the throat (pharynx) , voice box (larynx) and tonsils and swollen bull neck are considered stereotypical, although they may not show up in some cases.

Vaccine preventable

Diphtheria is a vaccine preventable disease – the toxoid vaccine elicits an immune response against the toxin which is encoded by a tox gene of the pathogen. Sometimes, spurts of diphtheria outbreaks occur in unvaccinated or partially vaccinated communities.

There is an increasing trend in the number of cases of diphtheria globally, as the number of cases in 2018 (16,651) was double the 1996–2017 average (8,105). Relevant to India is the statistic that 50% of the cases that came up in 2018 were in India.

To understand the epidemiology of the disease from a genetic perspective, it is needed to know how the microorganism has evolved in time and over the geographical spread. It is needed to know whether the gene for antimicrobial resistance has evolved and to understand variants of the tox gene which may be prevalent thereby influencing the vaccine targeted towards toxin produced by an old strain of C. diphtheriae.

Family tree

In order to map out the genetic spread of the organism, the group has done a phylogenetic analysis that basically gives a picture of the family tree of the species. Unlike certain other bacteria, C. diphtheriae has shown a diversity in evolution, which makes it, as a species, more stable and powerful. This is also true of clades (or groups) that are prevailing in India.

They then analyse the genes for their capacity towards antimicrobial resistance. Compared to the 1990s, isolates from the decade spanning the years from 2010 to 2019 show the highest average number of antimicrobial resistance genes encoding resistance for sulphonamide, aminoglycoside, chloramphenicol and trimethoprim.

Transferred AMR genes

“These antimicrobial resistance genes might have been transferred by the mobile genetic elements from other bacteria,” says Thandavaranyan Ramamurthy, one author of the paper. He is presently INSA-Senior Scientist at the ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, and the work was completed when he was at DBT-Translational Health Science and Technology Institute, Faridabad. “Fortunately, none of the isolates harboured beta-lactam resistance genes. [that is, for example, resistance to antibiotics like penicillin]. Penicillin or erythromycin are the choice of antibiotics for the treatment of diphtheria,” he explains.

Finally, the researchers study the variations (or mutations) in the tox gene, which is responsible for producing the diphtheria toxin – which is the main target of the vaccinations.

“We identified 18 tox gene variants, with mutations estimated in its toxin structural impact,” explains Dr. Ramamurthy. This may imply that specific vaccines made for a particular diphtheria toxin may not work against newly evolved ones. “However, this hypothesis has to be demonstrated in in vitro and in vivo studies,” he adds.

With a steady increase in the daily fresh coronavirus cases since the third week of February, with over 89,000 cases reported on April 2, the seven-day average test positivity rate climbing to 6.8% as on April 2, and with the reproduction number (R0) — how many people each infected person will infect on average — above 1.5 and steadily increasing over the last two–three weeks, the second wave has well and truly begun in many States. The rate of increase in cases in India during March has been faster than at any other time during the pandemic, which is also reflected in the modelling studies by Indian researchers, including Gautam Menon, Professor of Physics and Biology at Ashoka University. Modelling suggests that the previous peak in the number of cases (about 98,000) will soon be exceeded.

While the onset of the festival season since the pandemic peaked in mid-September in India, winter, no restrictions on movement, large gatherings and not-so-good adherence of mask wearing and other non-pharmaceutical interventions did not cause any spike in cases across the country, what is driving the current surge in cases in many States?

Cited reasons

The Health Ministry has cited the general laxity among people regarding COVID-19 appropriate behaviour, including mask wearing, and lack of containment and management strategy at the ground level as reasons for the surge in cases. The role of variants, either the imported ones or those that have originated in India, are not seen to be responsible.

But Dr. Giridhara Babu, epidemiologist at the Public Health Foundation of India (PHFI), Bengaluru cites three important factors — the virus, the host, and the environment — constituting the epidemiological triad for the surge in cases in many States. Explaining the contribution of the three factors, Dr. Babu says in an email: “New variants of concern might be in circulation, which is probably more infectious, and some can be an immune escape as well.” The host factors include waning antibodies, not following COVID-19 appropriate behaviour and incomplete vaccination, while the environmental factors include super-spreader events and poor compliance with preventive measures. The misconception that vaccination prevents even infection might also be contributing to rising cases.

Indian variants

“We just don’t know enough about the Indian variants to say whether they are more transmissible or more virulent, at this stage. I would personally think, extrapolating from the very high levels of seropositivity in the cities that several surveys have detected across the past several months, that a more transmissible, immune escape variant is responsible,” says Dr. Menon in an email to The Hindu.

In an email to The Hindu, virologist Dr. Shahid Jameel, Director of the Trivedi School of Biosciences at Ashoka University says variants, both imported and home-grown, are increasingly seen but have so far not been linked epidemiologically to the surge. “It is possible that may be the case, but there is no data to either support or negate that possibility,” he points out.

Explaining the tricky question of why no surge was seen between mid-September 2020 to end-February this year despite perfect conditions for the virus to spread wildly, Dr. Babu says the threshold for population immunity cannot be held as a yardstick when the virus is changing or when the immunity is waning. “Any infectious disease will have outbreaks whenever the susceptible pool builds up. Also, there has been the introduction of other variants due to international travel in some parts of the country, which can be more infectious than the earlier strain,” he says.

Surge in large cities

Large cities including Mumbai and Pune, which had recorded large infection rates during the first wave, are witnessing a surge. It is unclear if cases in such cities are only in virus-naïve people or if reinfections constitute a significant proportion. “There is no data I know of that is available in the public domain to address this question. Specifically, we don’t know what fraction of these new cases might reflect a new, more transmissible, immune escape variant that is responsible for reinfections,” says Dr. Menon. An ICMR study covering January-October 2020 found reinfection, most likely due to older strains, accounting for about 4.5% of cases.

According to Dr. Babu, in the cities that reported more than 50% of seroprevalence (at least in some parts), resurgence of cases would either suggest that the antibodies are rapidly waning (and are below threshold levels to mount a response) or presence of newer variants.

An imported variant (UK variant) has been identified in a few States. A double mutant variant has also been identified in at least a few States but all three experts feel that it is too early to conclusively say if this variant is responsible for higher transmission leading to a surge in cases or increased disease severity and death. This is because epidemiological link has so far not been established. That said, the U.K. variant and double mutant variant are considered to be more infectious and therefore more likely to contribute to intense transmission resulting in a faster peak wherever the variants are found.

Systematic study needed

One way to know if the variant is more infectious is by undertaking concurrent genomic sequencing of the cluster of cases and establishing the chain of transmission of the variants among the contacts, says Dr. Babu.

Only such a systematic study will help establish the epidemiological linkage of the variant. Also, in vitro testing is necessary to establish infectiousness. Similarly, the extent of morbidity caused by the variant can be established by tracking the clinical parameters of individual patients. “I am not sure if these studies are being done at sufficient scale and results are certainly not available in the public domain,” says Dr. Menon.

Also, against a target of sequencing at least 5% of positive samples across India to know the emergence of new variants, only 7,664 samples — less than 1% of the total positive samples from January to March 18 — have been sequenced. “The 5% is an aspiration, a vision. It can’t happen overnight. Capacity, systems and logistics have to be built for it. Since the INSACOG came together, India has seen about one million cases, and 11,000 sequences have been done. So, the rate is 1%. It needs to go up,” says Dr. Jameel. Dr. Menon adds: “The INSACOG group came together only in January and started working in February, so there's been relatively less time to ramp up.”

Undertaking studies to understand infectiousness of the double mutant variant becomes all the more important as noncompliance to COVID-19-appropriate behaviour is uniformly poor across India. Yet, the surge in cases is seen only in 19 States, and mainly in about a dozen States. In the absence of timely results of such studies, which will help policy making, placing all the blame on people appears to be the easy way out.

Carl Sagan once described Earth as a ‘small speck of dust’, a seemingly insignificant tiny particle. But dust has incredible power: it is known to influence monsoons, hurricanes and even fertilize rainforests. A new study now details how dust coming from the deserts in the West, Central and East Asia plays an important role in the Indian Summer Monsoon.

Reverse effect

The researchers also explain how the Indian Summer Monsoon has a reverse effect and can increase the winds in West Asia to produce yet more dust.

Dust swarms from the desert when lifted by strong winds can absorb solar radiation and become hot. This can cause heating of the atmosphere, change the air pressure, wind circulation patterns, influence moisture transport and increase precipitation and rainfall. A strong monsoon can also transport air to West Asia and again pick up a lot of dust. The researchers say this is a positive feedback loop.

Lead author Qinjian Jin, lecturer and academic program associate at the University of Kansas explains a new hypothesis formulated by the team to The Hindu. “Not just the dust from the Middle East [West Asia], we think the Iranian Plateau also influences the Indian Summer Monsoon. The hot air over the Iranian Plateau can heat the atmosphere over the plateau, strengthen the circulation over the deserts of the Arabian Peninsula and increase dust emission from the Middle East [West Asia].”

Aerosols transported

He explains how deserts across the globe play important roles in monsoons. “The dust aerosols from deserts in West China such as the Taklamakan desert and the Gobi Desert can be transported eastward to eastern China and can influence the East Asia summer monsoon. And in the southwest United States, we have some small deserts that influence the North African monsoon.”

When asked if anthropogenic dust from vehicles, mining, construction can influence monsoons, he explained: “Some studies have found that the anthropogenic aerosols emitted from the Indian subcontinent can decrease summer monsoon precipitation, while others found that absorbing aerosols such as dust can strengthen the monsoon circulation. However, in our study, we use the climate model to simulate the impact of anthropogenic aerosols on India and our results showed that they can strengthen Indian summer monsoon rainfall.” The findings were recently published in Earth-Science Reviews.

Why study dust?

But why is it important to study dust? Many studies have shown that the dust emission scheme is extremely sensitive to climate change and the team writes that understanding these mechanisms and effects of dust will help understand our monsoon systems in the face of global climate change.

Mineral components

The team has now planned to study the mineral components of desert dust aerosols. “We used to think that dust from deserts across the globe will have the same components, but we now know that different deserts have different chemical compositions and this can influence the dust’s properties. For example, we think that dust from the Middle East [West Asia] has more absorbing ability of solar radiation than dust from North Africa and this difference in absorbing ability might influence monsoon systems,” adds Dr. Jin. “We have also planned to use high spatial resolution remote sensing to identify source regions and create a better dust emission map. I would also like to study new drying lakes and how dust from them can also play a role in the monsoons.”

Since the first COVID-19 case was reported in India, the next four weeks will be the defining period in terms of how successful India’s COVID-19 response will be in controlling the ongoing, uncontrollable surge in virus spread across many States. Dr. Giridhara Babu, epidemiologist at the Public Health Foundation of India (PHFI), Bengaluru explains the possible reasons for the sudden surge and how the steep increase in cases can strain the healthcare system leading to more deaths.

The increase in daily cases has been very steep – from over 12,200 cases on March 1 to over 1,26,000 on April 7. The doubling time has reduced from 504 day on March 1 to 115 on April 4. What do you think is the reason for the increase in cases in a short time?

First, outbreaks can occur only when we cross the critical threshold level of a pool of susceptible persons. Over a while, there has been an accumulation of susceptible persons. Second, the disregard for COVID-19 appropriate behaviour (CAB) is ubiquitous all over the country.

Considering both as constant for all States in India, invoking Occam’s razor, the simplest explanation for the explosion of cases is the newer variants of concern. The newer strains are possibly more infectious, albeit not more lethal.

Can the exponential increase in daily cases be explained any other way other than a new, more infectious variant?

A small proportion of the population might have reinfections due to the waning antibodies. With newer areas seeing the surge in cases, we cannot rule out older variants spreading to these areas. There may be a dual problem facing the country. The old and newer variants might be in circulation in the uninfected regions in an earlier wave. Newer contagious variants might be spreading faster in urban pockets that had reached near-threshold levels of immunity. It is a pity that we do not have sufficient data from the field to explain the distinction between these.

The reproduction number (R0) crossed 1 on March 21 and is 1.54 as on April 6. Will increasing R0 suggest that the daily cases will increase further?

Based on the projections by several modellers, including Bhramar Mukherjee, Professor of Epidemiology at the University of Michigan, India will have nearly 1.8–3 lakh cases per day by May 1. The reproductive number is not decreasing, suggesting that there might be a higher number of cases in the next few weeks.

The active cases as on April 7 is over 9.05 lakh. If the daily cases continue to increase, what will be the number of active cases in the next few weeks/months?

The conservative projected estimates indicate that by May 1 India will have a total of over 17 million cases compared to 13 million now. Of the four million cases that will be added by May 1, two million will recover and we might have over two million active cases. Most of these will be asymptomatic cases. Hence, what matters is what proportion of these will have severe illness or succumb.

Why are we seeing more cases in States such as Maharashtra and cities such as Mumbai, Pune, Bengaluru and Chennai that experienced more virus spread in the first wave?

As we have seen in multiple health programmes, we have a skewed reporting problem in the country. States that report higher cases could be perhaps because they have a well-functioning surveillance system, and they test well. Apart from infecting susceptible people, the high number of cases in metros compared to the first wave is indicative of a more contagious variant of the virus at play.

As on April 8, the seven-day average test positivity rate has touched 9% nationally, while it has reached 26.5% in Maharashtra, 17.2% in Chhattisgarh, 13.1% in Chandigarh, and 10.8% in Madhya Pradesh. Does this not suggest that a large number of cases are being missed?

Yes, we are missing cases. Some states are missing more than others. Even where done, a relatively higher proportion of rapid antigen tests (RAT) done in some States confounds this problem even more. In case of symptomatic illness, the RAT might be a useful tool to diagnose and isolate the persons quickly. It is not very sensitive in asymptomatic persons. Therefore, in Karnataka’s technical advisory committee, we recommend that RT-PCR be the test of choice in all persons with asymptomatic illness.

Kerala has had a low seroprevalence, as suggested by ICMR and other surveys. After seeing a steady decline since the third week of January, an uptick in daily cases is seen in Kerala too. Will we see a surge in Kerala after a few weeks?

It is time that we speak of variant-specific thresholds of population immunity. If it’s the earlier variant, the low seroprevalence indicates that either a vast population is susceptible to the strain or the antibodies have waned over a period of time. For the newer variants, a vast majority of the people in the entire country, including Kerala, is susceptible, and case surge is a universal possibility in all States.

Is there any evidence that reinfections form a sizeable fraction of cases reported now?

The antibodies might be waning faster, and therefore, a small proportion of persons infected might be having reinfections. There is no robust data to prove the proportion of reinfections in India. Epidemiologically, we need to monitor all those who are positive for the RT-PCR test (Ct values less than 35) more than 90 days from the first episode, regardless of symptoms. The ICMR database will have these details. Studies can be done by matching unique identifying information such as mobile numbers and names etc.

With bed shortages already reported in Maharashtra and hospitals fast filling up in other States, what will the hospitalisation trend due to the accelerated increase in daily cases be?

More cases occurring in a short period will adversely impact the utilisation of the health system. Even if we assume that 5–10% of the cases are severe, we need 15,000–30,000 critical care beds (with oxygen) by May 1, assuming the trajectory continues as it is now, resulting in 3,00,000 cases each day. This will severely strain the health system, especially in areas that do not have robust infrastructure and human resources.

Most States are already reporting increased numbers of daily deaths. Is it possibly due to a new variant causing severe disease and death or due to healthcare facilities becoming strained and stretched beyond capacity?

There is a lag time of at least 10–17 days between case surge and death surges. Therefore, eventually, there will be a higher case fatality rate. The new variant might be more infectious but may not per se be causing more severe cases. As a result, there will be more cases in a short time. When the surge in cases is rapid, more persons with the severe disease might require critical care at the same time, resulting in a shortage of beds. This can increase mortality, as seen in most developed countries as well.

Without a national or Statewide lockdown, can increased containment measures including testing and tracing, adherence to COVID-appropriate behaviour, and increased vaccination coverage help reduce virus spread?

I have argued elsewhere that lockdown is a lazy policy option at this stage and should not replace the much-needed enhanced containment measures. In addition to enhanced testing and timely isolation and quarantine, we need to follow the 3C strategy. These include prevention of crowding of any nature, minimising the spread in closed spaces, especially with poor ventilation, and preventing the transmission in close-contact settings through strict enforcement of mask wearing.

Natural temperature differences which exist in the upper and lower respiratory tract influence the replication of the novel coronavirus and the subsequent activation of the immune system, says a new study that may lead to the development of new therapeutics and preventive measures against COVID-19.

The study, published in the journal PLOS Biology, assessed the growth of the novel coronavirus SARS-CoV-2, and activation of the immune system's cellular defense mechanisms.

In the research, scientists, including those from the University of Bern in Switzerland, compared the infection pathways of the novel coronavirus and the 2002-03 SARS-CoV pandemic virus in special cell cultures mimicking the respiratory tract.

"SARS-CoV-2 and SARS-CoV are highly similar genetically, generate a homologous repertoire of viral proteins, and use the same receptor to infect human cells. However, despite these similarities, there are also important differences between the two viruses," said study co-author Ronald Dijkman from the University of Bern.

While the 2002-03 pandemic virus is characterized by severe disease and inflammation in the lower respiratory tract, the scientists said SARS-CoV-2 preferentially replicates in the upper airways, including the nasal cavity and trachea.

According to the researchers, people infected with the SARS virus were only contagious after the onset of symptoms, making it easier to identify and interrupt infection chains, while the novel coronavirus is efficiently transmitted from one individual to another before the signs of disease appear.

The scientists used specialised human airway cell cultures to investigate the impact of respiratory tract temperatures on SARS-CoV and SARS-CoV-2 replication.

They found that temperature plays an important role as SARS-CoV-2 preferred to replicate at temperatures typically found in the upper airways of about 33 degrees Celsius.

When the researchers created colder conditions, they found that the virus replicated faster than when infections were carried out at 37 degrees Celsius to mimic the lower lung environment.

Unlike the novel coronavirus, they said the replication of SARS-CoV was not impacted by different incubation temperatures.

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When simulating conditions found in the upper airways, the team found that infection with SARS-CoV-2 did not induce immune response within these cells as strongly as it did when they mimicked conditions found in the lower respiratory tract.

"Since the strength of the innate immune response can directly influence the degree of viral replication, this may help explain why SARS-CoV-2 replicated more efficiently at lower temperatures," Dijkman said.

While a strong innate immune response against the virus is generally beneficial, the scientists cautioned that in some cases this could be overactivated, leading to high levels of inflammation, tissue damage and accelerated disease progression -- a phenomenon seen in patients suffering from severe COVID19.

"The detailed analysis of SARS-CoV-2 replication and the temperature-induced changes in the host innate immune defense mechanisms helps explain why SARS-CoV-2 replicates so well in the upper respiratory tract, and is perhaps why SARS-CoV-2 exhibits higher human-to-human transmissibility than SARS-CoV," Dijkman explained.

The researchers believe the findings may open new opportunities for the development of targeted intervention strategies and potential drug candidates to combat COVID-19.

Two positive tests at an interval of at least 102 days with one interim negative test have been defined as SARS-CoV-2 re-infection for establishing surveillance systems, according to an ICMR study. But a confirmation of the re-infection will require a whole genome sequencing, it stated.

According to the study published in the journal Epidemiology and Infection, an investigation was conducted with the objective to develop an epidemiological case definition of possible SARS CoV-2 re-infection and assess its magnitude in India.

SARS-CoV-2 re-infection is an emerging concern and there is a need to define it, the scientists highlighted. Therefore, working epidemiological case definition for re-infection was developed and its magnitude was explored via archive-based, telephonic survey.

The epidemiological case definition for SARS-CoV-2 reinfection was developed from literature review of data on viral kinetics.

Re-infection with SARS CoV-2 was defined as two positive tests at an interval of at least 102 days with one interim negative test. During the archive based, telephonic survey, thirty-eight of the 58 eligible patients could be contacted, with twelve (31.6%) being healthcare workers. Majority of the participants were asymptomatic.

"To conclude, a working epidemiological case definition of SARS CoV-2 re-infection is important to strengthen surveillance. The present investigation contributes to this goal and records reinfection in 4.5% of SARS CoV-2 infected individuals in India," the paper stated.

"Taking available evidence into consideration, re-infection with SARS CoV-2 in our study was defined as any individual who tested positive for SARS-CoV-2 on two separate occasions by either molecular tests or rapid antigen test at an interval of at least 102 days with one negative molecular test in between," the study stated. "While SARSCoV-2 re-infection is still a rare phenomenon, there is a need for epidemiological definition of re-infection for establishing surveillance systems and this study contributes to such goal."

Some respondents in the study had a symptomatic second episode as opposed to the first one. The rate and duration of hospitalisation was not compared as during the initial phase of the pandemic in India all cases were being hospitalized for at least 14 days, irrespective of symptom severity.

Currently, there is no consensus regarding the working definition of re-infection, based only on epidemiological features; a resource intensive method like whole genome sequencing being the only confirmation.

"It is not logistically feasible to store the samples of millions of positive cases for future sequencing to identify an important phenomenon like SARS CoV-2 re-infection," the study said.

Centers for Disease Control and Prevention (CDC) has considered the duration of 90 days between two positive SARS-CoV-2 RNA along with genomic evidence of re-infection as an investigative criterion to understand the phenomenon of reinfection.

Both CDC and European CDC suggested the use of genomic evidence for confirmation of reinfection, However, an epidemiological working definition will be more pragmatic and helpful to assess the magnitude of re-infection in most population and resource constrained settings.

While COVID-19 re-infection is still rarely reported, nonetheless, immunity should not be assumed and public health measures such as physical distancing, hand-hygiene, and use of masks should be followed after recovery from first event of infection, the study stated.

Further well-designed cohort studies must be undertaken to understand the natural history of COVID-19, including its immunogenicity, susceptibility to re-infection, antibody dependent enhancement and the severity of re-infections.

It may also be suggested that the samples of healthcare workers may be stored for genomic analysis to study suspected COVID-19 reinfections, particularly in resource limited settings as chances of them encountering such events are higher due to potential high-risk occupational exposure.

Disease-carrying mosquitoes, crop-ravaging rodents, forest-eating insects and even the domestic cat are all "exotic" intruders whose cost to humanity and the environment is vast and growing, according to a sweeping study published Wednesday.

Researchers in France estimate that invasive species have cost nearly $1.3 trillion dollars to the global economy since 1970, an average of $26.8 billion per year. And they warn that this is likely an underestimate.

In a study published in the journal Nature, scientists totted up the dizzying array of harmful effects from species carried between habitats, whether plants, insects, reptiles, birds, fish, molluscs, micro-organisms or mammals.

Beyond the "phenomenal magnitude" of these costs, there is also sign of a steady upward trend since 1970, said lead author Christophe Diagne, of the Ecology, Systematics and Evolution laboratory at the University of Paris-Saclay.

Most of the price tag is associated with the damage to ecosystems, crops or fisheries, although pest-control measures were also included in the research, an analysis of hundreds of studies that are part of a new invasive species database.

A preliminary roundup of the top ten invasive pests includes crop-eating rats and the Asian gypsy moth, which is attacking trees throughout the northern hemisphere.

It also included the tiger mosquito, native to Southeast Asia, which has become one of the worst invasive species in the world, carrying diseases like chikungunya, dengue and zika.

Average annual costs triple every decade, researchers said, in part because of an increase in scientific studies on this subject.

But there is also evidence of an "exponential increase in introduced species, due to growing international trade," said Franck Courchamp, director of the same Paris-Saclay laboratory. "We import lots of species, voluntarily or involuntarily."

Musseling in

It is a problem with a long history, linked to human trade, travel and colonialism.

In Australia, feral European rabbit populations were first reported in the early 1800s and their population exploded, reaching such proportions that they ravaged native species and caused billions of dollars of damage to crops. 

In 1950, the government released the disease myxomatosis, which only affects rabbits, killing over 90% of the wild bunnies. But some have since built up immunity.

The brown tree snake has eaten nearly all of the native birds and lizards of Guam since it was accidentally introduced in the mid-twentieth century from its South Pacific habitat, as well as causing power outages by infiltrating electrical installations and menacing people in their homes.

In the 1980s and 90s the zebra mussel, which originated in the waterways of the former Soviet Union, invaded North America's Great Lakes, blocking pipes, threatening native species and causing billions in damages.

On land, American forests — and more recently those in Europe — have been devastated by the Asian long-horned beetle.

While in Hawaii, the Puerto Rican coqui frog has found a new home with no natural predators — except local homeowners whose property values have tumbled thanks to its ear-splitting croak, which can reach 100 decibels.

'Incalculable'

Researchers hope that by putting a number on the cost of invasive species they can raise awareness of the enormity of the problem and push it higher on humanity's daunting list of environmental challenges.

But beyond the monetary estimate, the study said the "ecological and health impacts of invasions are at least as significant, yet often incalculable".

The UN's science advisory panel for biodiversity, called IPBES, has said invasive species are among the top five culprits — all human-driven — of environmental destruction worldwide, along with changes to land use, resource exploitation, pollution and climate change.

In 2019, IPBES estimated there had been a 70% increase in invasive species since 1970, in the 21 countries studied. And the worst could be to come, said Courchamp, who is taking part in upcoming IPBES research.

"International trade will cause more and more species to be introduced, while climate change will cause more and more of these introduced species to survive and become established," he said.

Early detection, better data and preventative measures could reduce costs considerably, the study said.

Courchamp said the domestic cat also has a lot to answer for — among the worst, in fact, in the researchers' top ten. The animal, which has been taken across the world for hundreds of years, is now "invasive in almost all the islands of the world", he said.

Domestic cats have been responsible for "the most killings in the world of birds, reptiles and amphibians, which are not prepared for this type of predator", he added.