Time Spent Talking, Not Just Physical Distance, Plays Role In Covid-19 Spread Researchers Say


Stay six feet apart — that’s the rule of thumb when it comes to social distancing. However, a new study suggests we need to take speech into account in addition to physical distancing when creating Covid-19 transmission mitigation strategies. By assessing the physics of saliva droplet formation and subsequent spray while a person speaks, researchers have shown the words we say play a role in how many droplets we spread — and how far they go.  

The paper, published in Physical Review Fluids, explores the mechanics behind transmission of droplets through speech. Manouk Abkarian of the University of Montpellier, France, and Howard Stone of Princeton University used high-speed videos to study how a talking person forms saliva droplets.

“Since there are many excellent studies on the size of droplets formed in some of these activities, we decided to study the airflows that would carry small droplets and aerosols from one person to another in casual interaction such as speaking,” says Stone, a professor of Mechanical and Aerospace Engineering with research interests in fluid dynamics.

Previous studies have also explored the role of speech in Covid-19 transmission. Earlier this year, researchers from the National Institutes of Health used laser light to observe droplet production. Their findings revealed that a person talking loudly even for just a second will emit thousands of droplets. Ironically, they found the phrase “stay healthy” is especially effective in sending saliva spraying, due to the pronunciation of “th.”

Similarly to the NIH study, Abkarian and Stone’s research suggested the length a person speaks is a more important factor in droplet spread than has been discussed in social distancing conversations thus far. “We were basically discovering that a ‘distance of security’ made no sense without introducing time in the problem,” says

China spent a record 2.2 trillion yuan on R&D in 2019 but needs to do more to escape US tech strangulation


a group of people standing in a room: A promoter dressed to look like an astronaut walks past a robot at the China Beijing International High Tech Expo in Beijing, China on Thursday, Sept. 17, 2020. Photo: AP

© AP
A promoter dressed to look like an astronaut walks past a robot at the China Beijing International High Tech Expo in Beijing, China on Thursday, Sept. 17, 2020. Photo: AP

Whatever the outcome of the upcoming US elections, most analysts agree that the tech rivalry between the US and China is unlikely to let up any time soon and therefore Beijing is expected to keep doubling down on its catch-up efforts.

China’s Ministry of Science and Technology last week vowed once again to look carefully at how the work of researchers is evaluated, ensuring that the focus is on research that “achieves real performance” as opposed to simply counting the number of publications.

This is part of Beijing’s wider drive to close a core science gap with the US and reduce its dependence on imported technology. Measures to revise the evaluation of researchers began in 2018 as part of a push to address a “paper-only” mindset and cover other criteria, such as academic titles, degrees attained and awards.

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Zhang Yewen, a professor of electrical engineering at Tongji University in Shanghai, said that although some progress had been made, awards are still being made to some scientists simply for having papers accepted by influential journals. Zhang said this needs reform although he acknowledged it cannot be stopped altogether.

“If you don’t refer to any of the four criteria, including which journal someone is published in, how can you evaluate their work,” said Zhang. “These judgments can only be made within a very small scientific circle and the public might not be aware of how we do this.”

World can benefit from China science

Amid the tech and trade war, China is

Joe Biden spent the first debate staring into the camera like Jim Halpert


Look out, Jim. There’s a new reaction guy in town, and his name’s Joe.

On Tuesday night, Joe Biden made his hometown of Scranton, Pennsylvania, proud by spending the majority of the first presidential debate imitating another famous Scranton man: Jim Halpert.

As fans of The Office know, Jim is the go-to camera reaction guy in Dunder Mifflin’s Scranton branch. His signature move is a look straight to camera, often accompanied by a smirk or a dumbfounded look — depending on the situation. And as the first debate unfolded, Biden essentially perfected Jim’s famous reaction.

For those who missed the debate (or simply blacked out from stress and can’t remember anything that happened) Donald Trump and Joe Biden had a tough time communicating. The two spent nearly 90 straight minutes talking over each other and moderator Chris Wallace, and at one point Biden got so frustrated with Trump’s constant interruptions that he simply said, “Will you shut up, man?”

Biden did try to exercise self-control and let Trump speak at times, but the president’s statements were often so outlandish that Biden couldn’t help but visibly react. Rather than vocally interrupt Trump, Biden spent much of the night laughing to himself and pulling a Jim Halpert by gazing directly into camera to meet the tired eyes of the American people watching at home.