Lotus will now bloom in Karnataka, Kerala, says Yogi Adityanath

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, Jun 4: Press Council of India (PCI) member BR Gupta has resigned from his post, saying he was unable to work individually or collectively for the media, which is in a "deep crisis".

"I have tendered my resignation as a Press Council of India member," Gupta told PTI.

He said the PCI had the responsibility to encourage media and media professionals constantly.

"But everyone now realises that the media scenario is in a deep crisis. The motto for which the Council was created was not being fulfilled and I felt I was not doing anything remarkable for the freedom of media," Gupta said.

He claimed that the PCI was not a wholly representative body for the media.

"Then how can we come out of the crisis being faced by the media and mediapersons? It is a big challenge for us. I have quit as I have not been able to work individually or collectively being a PCI member," Gupta added.

Referring to salary cuts and job losses, he said media and mediapersons were struggling for social, political and economic justice.

When contacted, PCI chairman Justice C K Prasad said Gupta's resignation has not been accepted yet.

"I have received it (the resignation). I have not gone through it. It has not been accepted," Prasad told PTI.

Gupta was appointed as a PCI member for a three-year term on May 30, 2018.

He said liberty is one of the basic features of the preamble to the Constitution that continues to inspire people and the media.

"It is difficult (for me) to fulfil the unbiased role and responsibility to help citizens and the media for making democracy stronger," Gupta said.