Amit Shah to introduce Citizenship Amendment bill in Lok Sabha today

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, Feb 12: Unidentified people opened fire at the convoy of the newly elected Aam Aadmi Party legislator Naresh Yadav in Southwest Delhi when he and his supporters were returning home after visiting a temple after his victory, killing a party volunteer, police and a senior AAP leader said.

The firing incident happened in Kishangarh village late Tuesday night.

Police said they have detained a person for questioning and the incident appears to be a case of personal enmity. Sources said seven rounds were fired at the MLA's convoy.

Another person injured in the incident has been admitted to a hospital.

AAP leader Sanjay Singh identified the dead party volunteer as Ashok Mann.

“Convoy of MLA Naresh Yadav attacked in Mehrauli, Ashok Mann killed. Naresh Yadav was returning home after visiting a temple,” Singh said in a tweet in Hindi.

“At least one volunteer has passed away due to bullet wounds. Another is injured,” AAP tweeted.

Ankit Lal, AAP's social media in-charge, added that miscreants in another car opened fire on the MLA's convoy near Fortis Hospital.

New Delhi, Jan 16: Chief of Defence Staff (CDS) General Bipin Rawat on Thursday said that he supported a negotiated peace deal between the US and Taliban in Afghanistan.

Gen. Rawat was speaking along with other world leaders at Raisina dialogue organised by India's influential think-tank Observer Research Foundation (ORF).

Arguing that terrorism was going to stay in the world as long as states were going to use it against other states, he said it was important to prevent states from using terrorism as a "proxy war".

"The only way to deal with it was what the US did post 9/11," he said, adding that the war against terror was necessary.

However, now a peace deal with Taliban is required, Gen. Rawat said.

"It must be a negotiated peace deal so that the Taliban stops using terrorism," he added. Hinting that the US should maintain its presence in Afghanistan, the CDS said that though Afghan security forces are now equipped to fight back terror groups in Afghanistan but they still need support.

The newly appointed CDS officially confirmed that India has shifted its stance on Taliban. India has traditionally been opposed to the Pakistan-backed Taliban in Afghanistan. Thousands of Afghans were given refuge in India when they fled the country due to oppression and terrorism of the Taliban regime. India is in alignment with the democratically elected government in Kabul that the Taliban remains supported by Pakistan.