Muslim girls allegedly forced to remove scarves for II PU exam at Canara College

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, May 3: Karnataka Government has allowed the movement of migrant workers, pilgrims, tourists, students and other persons who are stranded and also those who want to go to their residence as a "one-time measure" from district to district, after obtaining "one-day, one way" passes issued by concerned authorities.

Consequent to the Ministry of Home Affairs (MHA) new guidelines on lockdown measures, the government of Karnataka issued new guidelines on lockdown measures which will come into effect from May 4 for the period of two weeks.

In an order issued on Saturday, Chief Secretary and Chairman, State Executive Committee, Karnataka State Disaster Management Authority stated, "In the exercise of the powers, conferred under the Disaster Management Act, 2005, the undersigned, in his capacity of Chairman, State Executive Committee, hereby order to permit movement migrant workers, pilgrims, tourists, students and other persons who are stranded and also those people who want to go to their residence as a one-time measure from district to district with one-time one-day one-way passes issued by concerned Deputy Commissioners of the districts/Deputy Commissioner of Police in Commissionerates for strict implementation."

The details of the passes issued shall be shared by the issuing Deputy Commissioners of the districts/ Deputy Commissioner of Police with the receiving Deputy Commissioners of the districts/Deputy Commissioners of Police shall follow the SOPs prescribed by the Ministry of Health and Family Welfare for the movement of such persons, the order read.

It is reiterated that this would be a one-time one-day one-way pass for the individuals to reach their final destination.

Meanwhile, three deaths and 12 new COVID-19 cases were reported in the 24 hours in Karnataka, said the state Health Department on Saturday.

According to the Health Department, the total number of coronavirus positive cases in the State is now 601. 271 patients have either been cured or discharged. The virus has killed 25 people so far in the State.

New Delhi, Jun 22: Defence Minister Rajnath Singh on Monday left for a three-day visit to Russia. Singh is likely to discuss the India-Russia defence and strategic partnership during the visit and also attend a military parade in Moscow to mark the 75th anniversary of the Soviet victory over Nazi Germany in the Second World War.

The visit comes days after the violent face-off with China in which 20 Indian Armymen were killed in Galwan valley in Ladakh.

"Leaving for Moscow on a three day visit. The visit to Russia will give me an opportunity to hold talks on ways to further deepen the India-Russia defence and strategic partnership. I shall also be attending the 75th Victory Day Parade in Moscow," the Defence Minister tweeted.

Defence Secretary Ajay Kumar is also accompanying the minister.