PM Modi awarded Seoul Peace Prize: Dedicates prize money to Namami Gange

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.

Bengaluru, Mar 23: Indian stocks plunged over 9% on Monday, as the rapidly spreading coronavirus pandemic sent major states including the country's capital into a lockdown amid increasing fears that outbreak could bring world economies to a grinding halt.

The NSE Nifty 50 index slipped 9.17% to 7,937.75 by 0408 GMT, while the S&P BSE Sensex was 9.42% lower at 27,093.24.

Over the weekend in India, the virus drove several companies to shut operations and the government sent states into lockdowns, bringing normal life to a grinding halt.

"Panic has gone up domestically because of the lockdown situation," said Vinod Nair, head of research at Geojit Financial Services.

"There is fear that the situation will not be brought under control soon."

The rupee hit a fresh record low of 76.05 against the dollar, as a flight into cash and worries about tightening liquidity boosted demand for the world's reserve currency.

Meanwhile, global markets crumbled, with MSCI's broadest index of Asia-Pacific shares outside Japan sliding nearly 4% as the global death toll climbed to over 14,000, further battering economic activity, and raising fears of a global recession.

After market hours on Friday, the Securities and Exchange Board of India halved position limits for certain stock futures, restricted short-selling of index derivatives and raised margin rates for some shares to curb "abnormally high" volatility amid the pandemic.

In domestic trading, the Nifty PSU Bank Index plunged 8%, while the Nifty bank index crashed nearly 10%.

The Nifty Auto Index slid 9% after several carmakers over the weekend suspended production due to the virus.

New Delhi, Jan 24: The Election Commission of India on Friday told the Supreme Court that its 2018 direction asking poll candidates to declare their criminal antecedents in electronic and print media has not helped curb criminalisation of politics. The poll panel suggested that instead of asking candidates to declare criminal antecedents in the media, political parties should be asked not to give tickets to candidates with criminal background.

A bench of Justices R F Nariman and S Ravindra Bhat asked the ECI to come up with a framework within one week which can help curb criminalisation of politics in nation's interest.

The top court asked the petitioner BJP leader and advocate Ashiwini Upadhyay and the poll panel to sit together and come up with suggestions which would help him in curbing criminalisation of politics.

In September 2018, a five-judge Constitution bench had unanimously held that all candidates will have to declare their criminal antecedents to the Election Commission before contesting polls and had called for a wider publicity, through print and electronic media about antecedents of candidates.