Home-made face masks may need at least two layers to stop Covid-19 spread: Study

Washington, Jan 7: Facebook will ban deepfake videos ahead of the US elections but the new policy will still allow heavily edited clips so long as they are parody or satire, the social media giant said Tuesday.

Deepfake videos are hyper-realistic doctored clips made using artificial intelligence or programs that have been designed to accurately fake real human movements.

In a blog published following a Washington Post report, Facebook said it would begin removing clips that were edited--beyond for clarity and quality--in ways that "aren't apparent to an average person" and could mislead people.

Clips would be removed if they were "the product of artificial intelligence or machine learning that merges, replaces or superimposes content onto a video, making it appear to be authentic," the statement from Facebook vice-president Monika Bickert said.

However, the statement added: "This policy does not extend to content that is parody or satire, or video that has been edited solely to omit or change the order of words."

US media noted the new guidelines would not cover videos such as the 2019 viral clip -- which was not a deepfake -- of House Speaker Nancy Pelosi that appeared to show her slurring her words.

Facebook also gave no indication on the number of people assigned to identify and take down the offending videos, but said videos failing to meet its usual guidelines would be removed, and those flagged clips would be reviewed by teams of third-party fact-checkers -- among them AFP.

The news agency has been paid by the social media giant to fact-check posts across 30 countries and 10 languages as part of a program starting in December 2016, and including more than 60 organisations.

Content labeled "false" is not always removed from newsfeeds but is downgraded so fewer people see it -- alongside a warning explaining why the post is misleading.

Toronto, May 7: Scientists have uncovered how bats can carry the MERS coronavirus without getting sick, shedding light on what triggers coronaviruses, including the one behind the COVID-19 pandemic, to jump to humans.

According to the study, published in the journal Scientific Reports, coronaviruses like the Middle East respiratory syndrome (MERS) virus, and the COVID19-causing SARS-CoV-2 virus, are thought to have originated in bats.

While these viruses can cause serious, and often fatal disease in people, bats seem unharmed, the researchers, including those from the University of Saskatchewan (USask) in Canada, said.

"The bats don't get rid of the virus and yet don't get sick. We wanted to understand why the MERS virus doesn't shut down the bat immune responses as it does in humans," said USask microbiologist Vikram Misra.

In the study, the scientists demonstrated that cells from an insect-eating brown bat can be persistently infected with MERS coronavirus for months, due to important adaptations from both the bat and the virus working together.

"Instead of killing bat cells as the virus does with human cells, the MERS coronavirus enters a long-term relationship with the host, maintained by the bat's unique 'super' immune system," said Misra, one of the study's co-authors.

"SARS-CoV-2 is thought to operate in the same way," he added.

Stresses on bats, such as wet markets, other diseases, and habitat loss, may have a role in coronavirus spilling over to other species, the study noted.

"When a bat experiences stress to their immune system, it disrupts this immune system-virus balance and allows the virus to multiply," Misra said.

The scientists, involved in the study, had earlier developed a potential treatment for MERS-CoV, and are currently working towards a vaccine against COVID-19.

While camels are the known intermediate hosts of MERS-CoV, they said bats are suspected to be the ancestral host.

There is no vaccine for either SARS-CoV-2 or MERS, the researchers noted.

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"We see that the MERS coronavirus can very quickly adapt itself to a particular niche, and although we do not completely understand what is going on, this demonstrates how coronaviruses are able to jump from species to species so effortlessly," said USask scientist Darryl Falzarano, who co-led the study.

According to Misra, coronaviruses rapidly adapt to the species they infect, but little is known on the molecular interactions of these viruses with their natural bat hosts.

An earlier study had shown that bat coronaviruses can persist in their natural bat host for at least four months of hibernation.

When exposed to the MERS virus, the researchers said, bat cells adapt, not by producing inflammation-causing proteins that are hallmarks of getting sick, but instead by maintaining a natural antiviral response.

On the contrary, they said this function shuts down in other species, including humans.

The MERS virus, the researchers said, also adapts to the bat host cells by very rapidly mutating one specific gene.

These adaptations, according to the study, result in the virus remaining long-term in the bat, but being rendered harmless until something like a disease, or other stressors, upsets this balance.

In future experiments, the scientists hope to understand how the bat-borne MERS virus adapts to infection and replication in human cells.

"This information may be critical for predicting the next bat virus that will cause a pandemic," Misra said.

Ahmedabad, Feb 29: The presence of two feral pigeons onboard a GoAir flight at the airport in Ahmedabad in Gujarat created a flutter among the amused passengers, even though the avian surprise did not lead to any untoward incident or delay in the flight.

The incident took place on Friday when the passengers were boarding the Ahmedabad-Jaipur flight.

"Two pigeons had found their way inside the flight G8 702 while the passengers were boarding," an airline statement said on Saturday.

"The crew immediately shooed away the birds. The flight took off at its scheduled time at 5 p.m.," it added.

"Do Kabootar plane ke andar "
The passengers on the Ahmedabad-Jaipur flight were surprised when two #pigeons came out of the overhead storage bin of #GoAir Aircraft, minutes before flight was to take off, flight delayed by 30 minutes. "Video Viral" via : Satish Jha pic.twitter.com/orKuZ65Can

— Joydeep Roy (@IjoydeepRoy) February 29, 2020