Like Bajrang Dal, many Muslims have sacrificed lives for cow protection: RSS chief

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, Jun 10: Internet connectivity, provided under the central government's BharatNet initiative, will be improved in rural areas of Karnataka in the next two to three months, said Deputy Chief Minister CN Ashwath Narayan.

After video conferencing with heads of different agencies and officials, on improving the quality of internet in rural areas, Ashwath Narayan said, "I reviewed the progress of the BharatNet implementation and the steps to be taken to improve the quality of internet connectivity in the next two to three months."

"We also discussed the possibility of giving the implementation of BharatNet to a different agency. We will seek permission from the central government and continue the project. We will ease communication with rural people by ensuring quality and high-speed internet to all Gram Panchayats," he added.

When BSNL officials and other agency representatives who attended the video conference shared their problems, the Deputy Chief Minister assured to solve them through proper coordination.

"Through BharatNet, several government schemes are being implemented in rural areas. Civic service centres are issuing birth and death certificates, Aadhaar cards and social security pensions among others. Of the total 6,000 Gram Panchayats in the state, 4,000 have high-speed internet connectivity, and the remaining will be provided with better internet connectivity through a new agency,'' said Ashwath Narayan.

Additional Secretary (e-governance) Rajeev Chawla, Additional Chief Secretary (IT-BT) EV Ramana Reddy, Principal Secretary (RDPR) Uma Mahadevan, Director (IT) Meena Nagaraj, Collegiate Education Director Pradeep and other senior officials were present in the meeting.