BCCI bars Smith, Warner from this year's IPL

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.

London, Apr 25: Former Australian cricketer Graeme Watson who was fighting cancer, has died at the age of 75.

Primarily a middle-order batsman and a medium-pace bowler, he featured in five Tests from 1967 to 1972 and two ODIs in 1972, ESPNcricinfo reported.

The all-rounder earned the national call during the 1966-67 tour of Rhodesia and South Africa. Watson slammed a half-century in the first innings of the second Test of the series.

However, the medium-pace bowler was ruled of the next test after suffering an ankle injury. He returned for the fourth Test in Johannesburg where scalped his career-best 2 for 67 but failed to leave a mark with the bat as Kangaroos lost the series.

In 1971-72 he moved to Western Australia and played a major role in their Sheffield-Shield win in 1971-72, 1972-73, and 1974-75 seasons.

Former Australia batsman Mike Hussey has heaped praise on MS Dhoni, saying the veteran Indian wicketkeeper-batsman is the "greatest finisher" the game of cricket has ever seen.

"Dhoni is the greatest finisher of all time that the cricketing world has ever produced," Hussey said while speaking to Sanjay Manjrekar on ESPNcricinfo's Videocast.

"Dhoni can keep his cool and make the opposition captain blink first. Dhoni also has unbelievable power. He knows that when he needs to clear the ropes, he can do it. He has that kind of self-belief. Honestly, I didn't have that kind of belief in myself," he added.

The former Australian batsman, who shared the dressing room with Dhoni for the Chennai Super Kings, said the 38-year-old Indian believes in the philosophy that he who panics last, wins the game.

"I tried not to let it reach 12 or 13 runs an over," said Hussey while talking about his ability to finish the game without much hiccups.

"And I learnt this from MS Dhoni. He is incredible. He believes that he who panics last wins the game. So Dhoni would keep his cool, and keep it longer because the pressure is on the bowler as well," he added.

The 44-year-old believes that the greatest players of the game have a few common traits like "they don't hang on to a defeat for too long. If they lose, they move on quickly. They don't let a loss or a win hamper their thinking".

"They are always consistent, and level headed whether it's MS Dhoni or Ricky Ponting."

Hussey, who played 59 IPL matches for CSK, further revealed the secret about the franchise's success in the Indian Premier League.

"And I learnt this from MS Dhoni. He is incredible. He believes that he who panics last wins the game. So Dhoni would keep his cool, and keep it longer because the pressure is on the bowler as well," he added.

The 44-year-old believes that the greatest players of the game have a few common traits like "they don't hang on to a defeat for too long. If they lose, they move on quickly. They don't let a loss or a win hamper their thinking".

"They are always consistent, and level headed whether it's MS Dhoni or Ricky Ponting."

Hussey, who played 59 IPL matches for CSK, further revealed the secret about the franchise's success in the Indian Premier League.

"Supportive owners who let coach Stephen Fleming and captain Dhoni decide how to run the team, excellent chemistry between the coach and the captain, Dhoni's leadership and lastly the foresight of the owners, Fleming and Dhoni to pick the best players, particularly the good Indian players and then stick with them for as long as possible."

"This has built an excellent continuity in the team. And once you have continuity, you build relationships and trust that otherwise takes time to grow," he added.

Hussey also said that once Dhoni bids adieu to the game, CSK would probably like to start all over again.

"That's a 60-million-dollar question, and I am equally intrigued. I believe the owners would like to keep Dhoni involved in some way or the other," said Hussey.

"However, whenever the change of guard happens, CSK might want to start all over again, build a brand, new team, and use their existing philosophy as they enter the next decade of IPL. It is definitely going to be more challenging in current times," he added.

Dhoni was supposed to lead CSK in the 13th IPL edition which now stands postponed due to the coronavirus pandemic.