Riot in Argentine prison after coronavirus case confirmed

Washington, Mar 27: The United States has seen a record 18,000 new confirmed coronavirus cases and 345 deaths over the past 24 hours, according to a Johns Hopkins University tracker.

There are now 97,028 declared virus cases in the country and there have been 1,475 deaths, Johns Hopkins said.

Jun 15: Oil prices fell on Monday, with U.S. oil dropping more than 2%, as a spike in new coronavirus cases in the United States raised concerns over a second wave of the virus which would weigh on the pace of fuel demand recovery.

Brent crude futures fell 66 cents, or 1.7%, at $38.07 a barrel as of 0016 GMT, while U.S. West Texas Intermediate (WTI) crude futures fell 81 cents, or 2.2%, to $35.45 a barrel.

Both benchmarks ended down about 8% last week, their first weekly declines since April, hit by the U.S. coronavirus concerns: More than 25,000 new cases were reported on Saturday alone as more states, including Florida and Texas, reported record new infection highs.

"Concerns about the recent uptick in COVID-19 infections in the U.S. and a potential 'second wave' are weighing on oil at the moment," said Stephen Innes, chief global market strategist at AxiCorp.

Meanwhile, an OPEC-led monitoring panel will meet on Thursday to discuss ongoing record production cuts to see whether countries have delivered their share of the reductions, but will not make any decision, according to five OPEC+ sources.

The Organization of the Petroleum Exporting Countries (OPEC) and its allies, collectively known as OPEC+, have been reducing supplies by 9.7 million barrels per day (bpd), about 10% of pre-pandemic demand, and agreed in early June to extend the cuts for a month until end-July.

Iraq, one of the laggards in complying with the curbs, agreed with its major oil companies to cut crude production further in June, Iraqi officials working at the fields told Reuters on Sunday.

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.