UP civic poll: BJP sweeps big cities, but fails to open account in 36 districts

New Delhi, May 25: India witnessed the highest ever spike of 6,977 positive cases in the last 24 hours, taking the total number of COVID-19 to 1,38,845, according to the Union Ministry of Health and Family Welfare.

India is now among the top 10 countries in the world regarding the total number of COVID-19 cases.

With 154 deaths reported in the last 24 hours, the total number of deaths due to COVID-19 now stands at 4,021 in the country.

Out of the total number of cases, 77,103 are active cases and 57,721 have been cured/discharged/migrated.

Maharashtra continues to remain the worst affected state with 50,231 COVID-19 cases, followed by Tamil Nadu (16,277), Gujarat (14,056) and Delhi (13,418).

The fourth phase of the nationwide lockdown imposed as a precautionary measure to contain the spread of COVID-19 is scheduled to end on May 31.

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 26: The death toll in northeast Delhi communal violence over the amended citizenship law rose to 20 on Wednesday, according to GTB Hospital authorities.

On Tuesday, the death toll was 13.

"The death toll has risen to 20 today," Medical Superintendent of GTB Hospital, Sunil Kumar, told PTI.

Earlier, at least four bodies were brought to the Guru Teg Bahadur Hospital from the Lok Nayak Jai Prakash Narayan Hospital, a senior official said.