PM Modi visits Zvezda shipbuilding complex along with President Putin

Washington, Feb 21: US President Donald Trump has made yet another tall claim about the size of the crowd that will welcome him in Ahmedabad, saying Prime Minister Narendra Modi has told him that there will 10 million(1 crore) people to greet him on his arrival for his maiden visit to India.

President Trump and First Lady Melania are scheduled to travel to Ahmedabad, Agra and New Delhi on February 24 and 25.

Speaking to reporters at the Joint Base Andrews in Maryland on Tuesday, Trump said that Modi told him that "we'll have 7 million people between the airport and the event."

"So it's going to be very exciting. But he says between the stadium and the airport, we'll have about 7 million people. So it's going to be very exciting. I hope you all enjoy it," he said.

On Thursday, Trump upped the crowd size by three million at a 'Keep America Great' rally in Colorado.

"I hear, they are going to have 10 million people. They say anywhere from six to 10 million people are going to be showing up along the route to one of the largest stadiums in the world, the largest cricket stadium in the world, which is brand new and beautiful," said Trump, who is seeking reelection in the November presidential polls.

But according to a top civic official in Ahmedabad, the total population of the city is only around 70 lakh.

The authorities believe that between one to two lakh people are expected to line up along the 22-km route of the road show by Modi and Trump from the airport to the Motera cricket stadium, said to be the world's largest.

"We believe that around one to two lakh people will gather to welcome the dignitaries during the road show," Ahmedabad Municipal Commissioner Vijay Nehra said on Thursday, contradicting the claims made by the US President.

As per the road show route plan, Trump and Modi will first reach the Sabarmati Ashram, a place closely associated with Mahatma Gandhi, from Ahmedabad airport.

Addressing his supporters, Trump spoke about his India visit and said the "Namaste Trump" rally in Ahmedabad would spoil him.

"Prime Minister Modi said, we will have 10 million people greet you. Here's my problem. We have a packed house. We have a lot of people, thousands of people that couldn't get in. It's going to look like peanuts from now on," he said.

"I'll never be satisfied with the crowd. If we have 10 million people in India, how can I be satisfied when we fill up like a 60,000-seat stadium? I am getting spoiled," Trump said.

One of Trump's supporters from the audience then suggested that he build a bigger stadium.

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.

Washington, Jul 1: The United States has approved four coronavirus vaccine candidates for clinical trials, Food and Drug Administration (FDA) head Stephen Hahn told reporters.

"Four vaccines have been approved for moving into clinical trials... and another six are in the pipeline for us to review," Hahn said during a press briefing on Tuesday.

The US Administration launched in May Operation Warp Speed, a joint project of Health and Defense Departments, which aims to deliver 300 million doses of a vaccine for COVID-19 by January 2021.

The country's top pandemics expert Anthony Fauci warned on Tuesday, however, that there is no certainty the United States will be able to develop a vaccine against COVID-19 that works and will be safe.

Data on vaccine effectiveness, he added, may be available in the winter or early next year.