Astronomers discover 83 supermassive black holes 13 billion light-years away

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.

Riyadh, May 22: The family of murdered Saudi journalist Jamal Khashoggi on Friday said that they forgave his killers. Washington Post journalist Jamal Khashoggi, who had written columns critical of Saudi Arabia, was brutally killed in October 2018, allegedly at the behest of Crown Prince Mohammad bin Salman.

“In this blessed night of the blessed month [of Ramadan] we remember God’s saying: If a person forgives and makes reconciliation, his reward is due from Allah,” Jamal Khashoggi’s son Salah Khashoggi said in a tweet. “Therefore, we the sons of the Martyr Jamal Khashoggi announce that we pardon those who killed our father, seeking reward [from] God almighty.”

The legal outcome of this announcement is not yet clear. Earlier, Salah Khashoggi said he had “full confidence” in the judicial system, and that the accused were trying to exploit the case.

Jamal Khashoggi’s body was said to have been dismembered inside the Saudi consulate in Istanbul and disposed of elsewhere, but his remains were never found.

New Delhi, Jan 11: Islamic preacher Zakir Naik has revealed that the Bharatiya Janata Party-led government offered to drop false money-laundering charges against him and provide with a "safe passage to India" in return for his support to the government's move to revoke Article 370 of the Constitution.

In a statement issued by Naik's PR team on Saturday, the Islamic preacher said that he was approached by a representative of the Indian government in September, who offered him the said deal on Kashmir, which he refused.

"Three and a half months before, the Indian officials approached me for a private meeting with a representative of the Indian government. When he came to Putrajaya (a Malaysian city), in the fourth week of September 2019, to meet me, he said that he is coming after personally meeting and under the direct instructions of the Prime Minister of India Narendra Modi and the Home Minister of India Amit Shah," Naik said in a video statement released by his Mumbai-based PR team.

Naik, who has been living in Malaysia for the last three years, is facing charges of inciting communal disharmony and committing unlawful activities in India.

"(The representative) said that he wanted to remove the misconceptions and miscommunications between myself (Naik) and the Indian government, and wants to provide me a safe passage to India," he added. "He (the representative) said that he would like to use my connections to better the relationship between India and the other Muslim countries."

"The meeting lasted for several hours. He told me that he wanted me to support the BJP government when they revoked Article 370 in Kashmir. And I flatly refused," he added.

Naik said that after he refused the offer, he was further asked to not make public statements against the BJP or Prime Minister Narendra Modi.