Anupam Kher is the new FTII chairman, replaces Gajendra Chauhan

London, May 20: The current physical distancing guidelines of 6 feet may be insufficient to prevent COVID-19 transmission, according to a study which says a mild cough in low wind speeds can propel saliva droplets by as much as 18 feet.

Researchers, including those from the University of Nicosia in Cyprus, said a good baseline for studying the airborne transmission of viruses, like the one behind the COVID-19 pandemic, is a deeper understanding of how particles travel through the air when people cough.

In the study, published in the journal Physics of Fluids, they said even with a slight breeze of about four kilometres per hour (kph), saliva travels 18 feet in 5 seconds.

"The droplet cloud will affect both adults and children of different heights," said study co-author Dimitris Drikakis from the University of Nicosia.

According to the scientists, shorter adults and children could be at higher risk if they are located within the trajectory of the saliva droplets.

They said saliva is a complex fluid, which travels suspended in a bulk of surrounding air released by a cough, adding that many factors affect how saliva droplets travel in the air.

These factors, the study noted, include the size and number of droplets, how they interact with one another and the surrounding air as they disperse and evaporate, how heat and mass are transferred, and the humidity and temperature of the surrounding air.

In the study, the scientists created a computer simulation to examine the state of every saliva droplet moving through the air in front of a coughing person.

The model considered the effects of humidity, dispersion force, interactions of molecules of saliva and air, and how the droplets change from liquid to vapour and evaporate, along with a grid representing the space in front of a coughing person.

Each grid, the scientists said, holds information about variables like pressure, fluid velocity, temperature, droplet mass, and droplet position.

The study analysed the fates of nearly 1,008 simulated saliva droplets, and solved as many as 3.7 million equations.

"The purpose of the mathematical modelling and simulation is to take into account all the real coupling or interaction mechanisms that may take place between the main bulk fluid flow and the saliva droplets, and between the saliva droplets themselves," explained Talib Dbouk, another co-author of the study.

However, the researchers added that further studies are needed to determine the effect of ground surface temperature on the behaviour of saliva in air.

They also believe that indoor environments, especially ones with air conditioning, may significantly affect the particle movement through air.

This work is important since it concerns safety distance guidelines, and advances the understanding of the transmission of airborne diseases, Drikakis said.

New Delhi, Mar 4: The government on Wednesday permitted NRIs to own up to 100 per cent stake in disinvestment-bound Air India.

The decision comes at a time when the government is looking to sell 100 per cent stake sale in the national carrier.

Union minister Prakash Javadekar said the Cabinet has approved allowing Non-Residents Indians (NRIs) to hold up to 100 per cent stake in Air India.

Allowing 100 per cent investment by Non-Resident Indians (NRIs) in the carrier would also not be in violation of SOEC norms. NRI investments would be treated as domestic investments.

Under the Substantial Ownership and Effective Control (SOEC) framework, which is followed in the airline industry globally, a carrier that flies overseas from a particular country should be substantially owned by that country's government or its nationals.

Currently, NRIs can acquire only 49 per cent in Air India. Foreign Direct Investment (FDI) in the airline is also 49 per cent through the government approval route.

As per the existing norms, 100 per cent FDI is permitted in scheduled domestic carriers, subject to certain conditions, including that it would not be applicable for overseas airlines.

In the case of scheduled airlines, 49 per cent FDI is permitted through automatic approval route and any such investment beyond that level requires government nod.

On January 27, the government came out witha Preliminary Information Memorandum (PIM) for Air India disinvestment. It has proposed selling 100 per cent stake in Air India along with budget airline Air India Express and the national carrier's 50 per cent stake in AISATS, an equal joint venture with Singapore Airlines.

Under the latest disinvestment plan, the successful bidder would have to take over only debt worth Rs 23,286.5 crore while the liabilities would be decided depending on current assets at the time of closing of the transaction.

This is the second attempt by the government in as many years to divest Air India, which has been in the red for long.

New Delhi, Mar 10: A military transport aircraft of the Indian Air Force (IAF) brought back 58 Indians from coronavirus-hit Iran on Tuesday, official said.

The aircraft, a C-17 Globemaster, was sent to Tehran on Monday evening.

About 2,000 Indians are living in Iran, a country that has witnessed increasing numbers of coronavirus cases in the last few days.

"The IAF aircraft has landed. Mission completed. On to the next," External Affairs Minister S Jaishankar tweeted.

In an earlier tweet, he said, "First batch of 58 Indian pilgrims being brought back from Iran. IAF C-17 taken off from Tehran and expected to land soon in Hindon."

"Thanks to the efforts of our Embassy @India_in_Iran and Indian medical team there, operating under challenging conditions. Thank you @IAF_MCC. Appreciate cooperation of Iranian authorities. We are working on the return of other Indians stranded there (sic)," Jaishankar added.

The aircraft landed at Hindon airbase in Ghaziabad, from where the passengers were take to a medical facility.

According to latest reports, 237 people have died of novel coronavirus in Iran while the number of positive cases stands at around 7,000.

It is the second such evacuation by the C-17 Globemaster in the last two weeks.

On February 27, 76 Indians and 36 foreign nationals were brought back from the Chinese city of Wuhan by the aircraft of the Indian Air Force.

The C-17 Globemaster is the largest military aircraft in the IAF's inventory. The plane can carry large combat equipment, troops and humanitarian aid across long distances in all weather conditions.

Four days ago, a Mahan airline plane brought swab samples of 300 Indians from Iran to India.