Six feet distancing not enough to stop coronavirus transmission in light winds: Study

News Network
May 20, 2020

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.

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News Network
January 17,2020

Bengaluru, Jan 17: India’s latest communication satellite GSAT-30 was successfully launched from the Spaceport in French Guiana during the early hours on Friday.

In a press release, ISRO, has stated that the launch vehicle 'Ariane-5 VA-251' was blasted off from Kourou Launch Base, French Ginana at 0230 hours, carrying India’s GSA-30 and EUTELSAT KONNECT for Eutelasat, as per schedule.

The Ariane 5 upper stage in an elliptical Geosynchronous Transfer Orbit.

With a lift-off mass of 3,357 kg, GSAT-30 will provide continuity to operational services on some of the in-orbit satellites.

GSAT-30 derives its heritage from ISRO’s earlier INSAT/GSAT satellite series and will replace INSAT-4A in orbit.

“GSAT-30 has a unique configuration of providing flexible frequency segments and flexible coverage. The satellite will provide communication services to Indian mainland and islands through Ku-band and wide coverage covering Gulf countries, a large number of Asian countries and Australia through C-band," ISRO Chairman Dr K Sivan said.

Dr Sivan also said that “GSAT-30 will provide DTH Television Services, connectivity to VSATs for ATM, Stock-exchange, Television uplinking and teleport Services, Digital Satellite News Gathering (DSNG) and e-governance applications. The satellite will also be used for bulk data transfer for a host of emerging telecommunication applications.”

ISRO’s Master Control Facility (MCF) at Hassan in Karnataka took over the command and control of GSAT-30 immediately after its separation from the launch vehicle. Preliminary health checks of the satellite revealed its normal health.

In the days ahead, orbit-raising maneuvers will be performed to place the satellite in Geostationary Orbit (36,000 km above the equator) by using its onboard propulsion system.

During the final stages of its orbit raising operations, the two solar arrays and the antenna reflectors of GSAT-30 will be deployed. Following this, the satellite will be put in its final orbital configuration.

The satellite will be operational after the successful completion of all in-orbit tests.

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Agencies
January 21,2020

New Delhi, Jan 21: With the IMF lowering India's economic growth estimate for the current fiscal to 4.8 per cent, senior Congress leader P Chidambaram on Tuesday claimed an attack on the world body and its chief economist Gita Gopinath by government ministers was imminent.

He also alleged that the growth figure of 4.8 per cent given by the International Monetary Fund (IMF) is after some "window dressing" and he won't be surprised if it goes even lower.

"Reality check from IMF. Growth in 2019-20 will be BELOW 5 per cent at 4.8 per cent," Chidambaram said in a series of tweets.

"Even the 4.8 per cent is after some window dressing. I will not be surprised if it goes even lower," the former finance minister said.

IMF Chief Economist Gopinath was one of the first to denounce demonetisation, he noted.

"I suppose we must prepare ourselves for an attack by government ministers on the IMF and Dr Gita Gopinath," Chidambaram said.

The IMF lowered India's economic growth estimate for the current fiscal to 4.8 per cent and listed the country's much lower-than-expected GDP numbers as the single biggest drag on its global growth forecast for two years.

In October, the IMF had pegged India economic growth at 6.1 per cent for 2019.

Listing decline in rural demand growth and an overall credit sluggishness for lowering of India forecasts, Gopinath, however, had said the growth momentum should improve next year due to factors like positive impact of corporate tax rate reduction.

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News Network
February 12,2020

Feb 12: China on Wednesday reported another drop in the number of new cases of a viral infection and 97 more deaths, pushing the total dead past 1,100 as postal services worldwide said delivery was being affected by the cancellation of many flights to China.

The National Health Commission said 2,015 new cases had been reported over the last 24 hours, declining for a second day. The total number of cases in mainland China reached 44,653, although many experts say a large number of others infected have gone uncounted.

The additional deaths raised the mainland toll to 1,113. Two people have died elsewhere, one in Hong Kong and one in the Philippines.

In the port city of Tianjin, just southeast of Beijing, a cluster of cases has been traced to a department store in Baodi district. One-third of Tianjin’s 104 confirmed cases are in Baodi, the Xinhua state news agency reported.

A salesperson working in the store’s small home appliance section became the first individual in the cluster to be diagnosed on Jan. 31, Xinhua said. The store was already closed at that point, then disinfected on Feb. 1. Nevertheless, several more diagnoses soon followed.

The next to have their infections confirmed were also salespeople at the store. They had not visited Wuhan recently and, with the exception of one married couple, the patients worked in different sections of the store and did not know one another, according to Xinhua.

Japan’s Health Ministry said that 39 new cases have been confirmed on a cruise ship quarantined at Yokohama, bringing the total to 174 on the Diamond Princess.

The U.S. Postal Service said that it was “experiencing significant difficulties” in dispatching letters, parcels and express mail to China, including Hong Kong and Macau.

Both the U.S. and Singapore Post said in notes to their global counterparts that they are no longer accepting items destined for China, “until sufficient transport capacity becomes available.”

The Chinese mail service, China Post, said it was disinfecting postal offices, processing centers and vehicles to ensure the virus doesn’t spread via the mail and to protect staff.

It said the crisis is also impacting mail that transits China to other destinations including North Korea, Kazakhstan, Kyrgyzstan, Mongolia, Tajikistan, Turkmenistan, Uzbekistan and Vietnam.

The World Health Organization has named the disease caused by the virus as COVID-19, avoiding any animal or geographic designation to avoid stigmatization and to show the illness comes from a new coronavirus discovered in 2019.

The illness was first reported in December and connected to a food market in the central Chinese city of Wuhan, where the outbreak has largely been concentrated.

Zhong Nanshan, a leading Chinese epidemiologist, said that while the virus outbreak in China may peak this month, the situation at the center of the crisis remains more challenging.

“We still need more time of hard working in Wuhan,” he said, describing the isolation of infected patients there a priority.

“We have to stop more people from being infected,” he said. “The problem of human-to-human transmission has not yet been resolved.”

Without enough facilities to handle the number of cases, Wuhan has been building prefabricated hospitals and converting a gym and other large spaces to house patients and try to isolate them from others.

China’s official media reported Tuesday that the top health officials in Hubei province, of which Wuhan is the capital, have been relieved of their duties. No reasons were given, although the province’s initial response was deemed slow and ineffective. Speculation that higher-level officials could be sacked has simmered, but doing so could spark political infighting and be a tacit admission of responsibility.

The virus outbreak has become the latest political challenge for the party and its leader, Xi Jinping, who despite accruing more political power than any Chinese leader since Mao Zedong, has struggled to handle crises on multiple fronts. These include a sharply slowing domestic economy, the trade war with the U.S. and pushback on China’s increasingly aggressive foreign policies.

China is struggling to restart its economy after the annual Lunar New Year holiday was extended to try to curb the spread of the virus. About 60 million people are under virtual quarantine and many others are still working at home.

In Hong Kong, the diagnosis of four people living in an apartment building prompted worried comparisons with the deadly SARS pandemic of 17 years ago.

More than 100 people were evacuated from the building after a 62-year-old woman diagnosed with the virus was found living 10 floors directly below a man who was earlier confirmed with the virus.

Health officials called it a precautionary measure and sought to assuage fears of an epidemic, dismissing similarities to the SARS community outbreak at the Amoy Gardens housing estate in 2003.

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