13 booked for firing air shots at Mahatma Gandhi's effigy

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, Jan 18: Lieutenant Governor (LG) Anil Baijal has granted the power of detaining authority to the Delhi Police Commissioner under the National Security Act (NSA), according to a notification. The NSA allows preventive detention of an individual for months if the authorities feel that the individual is a threat to the national security, and law and order, sources said.

In exercise of the powers conferred by sub-section (3) of section 3, read with clause (c) of Section 2 of the National Security Act, 1980, the Lt Governor is pleased to direct that during the period January 19 to April 18, the Delhi Police Commissioner may also exercise the powers of detaining authority under sub-section (2) of the section 3 of the aforesaid Act, the notification stated.

The notification has been issued on January 10 following the approval of the LG.

It comes at a time when the national capital has been witnessing a number of protests against the Citizenship Amendment Act (CAA) and the National Register of Citizens (NRC).

However, the Delhi Police said it is a routine order that has been issued in every quarter and has nothing to do with the current situation.

Dubai, Jan 9: A roadshow promoting Gujarat as an education hub of India will be held here from January 17, officials said.

Representatives of 22 universities and four colleges from Gujarat will be part of the two-day event organised by the Indian Consulate in Dubai.

"The roadshow will provide a glimpse of the thriving education sector in Gujarat and enable the interested candidates to get a first-hand understanding of the rich resources of the state in order to pursue higher education," according to a statement released by the Indian Consulate here on Wednesday.

A delegation led by Gujarat's Education Minister Bhupendrasinh Chudasama will take part in the event under the 'Study in Gujarat' campaign, the statement said.

The Principal Secretary of the state's Higher and Technical Education, Anju Sharma, will participate in the roadshow, which will conclude on January 18.

The participating educational institutions include Pandit Deendayal Petroleum University, Gujarat Forensic Science University, Nirma University, LD College of Engineering, Gujarat Arts and Science College, Vishwakarma Government College and SAL College.

"In the last decade and a half, Gujarat has been successful in establishing its identity as the leading educational hub of India. State of the art infrastructure, safe environment, curriculum at par with international standards and industry exposure gives students an edge during the course of their study," the statement said.