Degree holders may wait for 150 years for a green card

Washington, May 30: US President Donald Trump on Friday said that America is terminating its relationship with the World Health Organization as he blamed it and China for the deaths and destruction caused by the COVID-19 pandemic across the globe.

Stating that the funding of the WHO would now be diverted to other global public health organisations, Trump announced a series of decisions against China including issuing proclamation to deny entry to certain Chinese nationals and tightening of regulations against Chinese investments in America.

"Because they (WHO) have failed to make the requested and greatly needed reforms, we will be today terminating our relationship with the World Health Organization and redirecting those funds to other worldwide and deserving urgent global public health needs, Trump said.

May 22: A Pakistan International Airlines (PIA) flight on its way from Lahore to Karachi, crashed in the area near Jinnah International Airport on Friday, according to Civil Aviation Authority officials.

Geo News reported that the plane crashed at the Jinnah Ground area near the airport as it was approaching for landing. There were more than 90 passengers on board the Airbus aircraft. Black smoke could be seen from afar at the crash site, say eye witnesses.

There were no immediate reports on the number of casualties. The aircraft arriving from the eastern city of Lahore was carrying 99 passengers and 8 crew members, news agency AP said, quoting Abdul Sattar Kokhar, spokesman for the country’s civil aviation authority.

Witnesses said the Airbus A320 appeared to attempt to land two or three times before crashing in a residential area near Jinnah International Airport.

Flight PK-303 from Lahore was about to land in Karachi when it crashed at the Jinnah Garden area near Model Colony in Malir, just a minute before its landing, Geo News reported.

Local television reports showed smoke coming from the direction of the airport. Ambulances were on their way to the airport.

News agency said Sindh’s Ministry of Health and Population Welfare has declared emergency in all major hospitals of Karachi due to the plane crash.

It’s the second plane crash for Pakistani carrier in less than four years. The airline’s chairman resigned in late 2016, less than a week after the crash of an ATR-42 aircraft killed 47 people. The incident comes as Pakistan was slowly resuming domestic flights in the wake of the coronavirus pandemic, Bloomberg reported.

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.