NASA probe beams back ultraviolet images of Martian atmosphere

October 18, 2016

Washington, Oct 18: In a first, NASA's MAVEN spacecraft has beamed back ultraviolet images of Mars that unveils dynamic, previously invisible activities in the atmosphere of the red planet such as change in ozone levels over the seasons and formation of clouds.master

The images were taken by the Imaging UltraViolet Spectrograph (IUVS) on the Mars Atmosphere and Volatile Evolution mission (MAVEN) - a space probe designed to study the Martian atmosphere while orbiting Mars.

These were then used to make this movie of rapid cloud formation on Mars on July this year.

The movie uses four MAVEN images to show about seven hours of Mars rotation during this period, and interleaves simulated views that would be seen between the four images.

"MAVEN obtained hundreds of such images in recent months, giving some of the best high-resolution ultraviolet coverage of Mars ever obtained," said Nick Schneider from the University of Colorado, Boulder in the US.

Nightside images show ultraviolet (UV) "nightglow" emission from nitric oxide (NO). Nightglow is a common planetary phenomenon in which the sky faintly glows in the complete absence of external light.

Mars' nightside atmosphere emits light in the ultraviolet due to chemical reactions that start on Mars' dayside.

Ultraviolet light from the Sun breaks down molecules of carbon dioxide and nitrogen, and the resulting atoms are carried around the planet by high-altitude wind patterns that encircle the planet.

On the nightside, these winds bring the atoms down to lower altitudes where nitrogen and oxygen atoms collide to form nitric oxide molecules. The recombination releases extra energy, which comes out as ultraviolet light.

Scientists predicted NO nightglow at Mars, and prior missions detected its presence, but MAVEN has returned the first images of this phenomenon in the Martian atmosphere.

Splotches and streaks appearing in the images occur where NO recombination is enhanced by winds.

Such concentrations are clear evidence of strong irregularities in Mars' high altitude winds and circulation patterns. These winds control how Mars' atmosphere responds to its very strong seasonal cycles.

Dayside images show the atmosphere and surface near Mars' south pole in unprecedented ultraviolet detail. They were obtained as spring comes to the southern hemisphere.

Ozone is destroyed when water vapour is present, so ozone accumulates in the winter polar region where the water vapour has frozen out of the atmosphere.

The images show ozone lasting into spring, indicating that global winds are inhibiting the spread of water vapour from the rest of the planet into winter polar regions.

MAVEN observations also show afternoon cloud formation over the four giant volcanoes on Mars.
Clouds are a key to understanding a planet's energy balance and water vapour inventory, so these observations will be valuable in understanding the daily and seasonal behaviour of the atmosphere, researchers said.

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News Network
May 19,2020

May 19: A Chinese laboratory has been developing a drug it believes has the power to bring the coronavirus pandemic to a halt.

The outbreak first emerged in China late last year before spreading across the world, prompting an international race to find treatments and vaccines.

A drug being tested by scientists at China's prestigious Peking University could not only shorten the recovery time for those infected, but even offer short-term immunity from the virus, researchers say.

Sunney Xie, director of the university's Beijing Advanced Innovation Center for Genomics, told AFP that the drug has been successful at the animal testing stage.

"When we injected neutralising antibodies into infected mice, after five days the viral load was reduced by a factor of 2,500," said Xie.

"That means this potential drug has (a) therapeutic effect."

The drug uses neutralising antibodies -- produced by the human immune system to prevent the virus infecting cells -- which Xie's team isolated from the blood of 60 recovered patients.

A study on the team's research, published Sunday in the scientific journal Cell, suggests that using the antibodies provides a potential "cure" for the disease and shortens recovery time.

Xie said his team had been working "day and night" searching for the antibody.

"Our expertise is single-cell genomics rather than immunology or virology. When we realised that the single-cell genomic approach can effectively find the neutralising antibody we were thrilled."

He added that the drug should be ready for use later this year and in time for any potential winter outbreak of the virus, which has infected 4.8 million people around the world and killed more than 315,000.

"Planning for the clinical trial is underway," said Xie, adding it will be carried out in Australia and other countries since cases have dwindled in China, offering fewer human guinea pigs for testing.

"The hope is these neutralised antibodies can become a specialised drug that would stop the pandemic," he said.

China already has five potential coronavirus vaccines at the human trial stage, a health official said last week.

But the World Health Organization has warned that developing a vaccine could take 12 to 18 months.

Scientists have also pointed to the potential benefits of plasma -- a blood fluid -- from recovered individuals who have developed antibodies to the virus enabling the body's defences to attack it.

More than 700 patients have received plasma therapy in China, a process which authorities said showed "very good therapeutic effects".

"However, it (plasma) is limited in supply," Xie said, noting that the 14 neutralising antibodies used in their drug could be put into mass production quickly.

Using antibodies in drug treatments is not a new approach, and it has been successful in treating several other viruses such as HIV, Ebola and Middle East Respiratory Syndrome (MERS).

Xie said his researchers had "an early start" since the outbreak started in China before spreading to other countries.

Ebola drug Remdesivir was considered a hopeful early treatment for COVID-19 -- clinical trials in the US showed it shortened the recovery time in some patients by a third -- but the difference in mortality rate was not significant.

The new drug could even offer short-term protection against the virus.

The study showed that if the neutralising antibody was injected before the mice were infected with the virus, the mice stayed free of infection and no virus was detected.

This may offer temporary protection for medical workers for a few weeks, which Xie said they are hoping to "extend to a few months".

More than 100 vaccines for COVID-19 are in the works globally, but as the process of vaccine development is more demanding, Xie is hoping that the new drug could be a faster and more efficient way to stop the global march of the coronavirus.

"We would be able to stop the pandemic with an effective drug, even without a vaccine," he said.

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News Network
March 11,2020

Rome, Mar 11: Italy has recorded its deadliest day of the coronavirus crisis despite locking down the entire country, as New York deployed the National Guard to contain a disease that has sown worldwide panic.

The hardest-hit country in Europe said its death toll from the COVID-19 virus had risen Tuesday by a third to 631, with the surging epidemic taking its toll on global sporting, cultural and political events.

While authorities in China, where the outbreak began, have declared it "basically curbed", cases are multiplying around the world, sparking panic buying in shops, and wild swings on financial markets.

China remains the hardest-hit overall with more than 80,000 cases and over 3,000 deaths, out of a global total of 117,339 cases and 4,251 deaths across 107 countries and territories, according to an AFP tally.

The virus is infecting all walks of life, including politics, with US Democratic presidential hopefuls Bernie Sanders and Joe Biden both cancelling campaign rallies and British health minister Nadine Dorries saying she had tested positive.

And amid criticism of the US authorities' response, New York deployed the National Guard for the first time during the crisis to help contain the spread of the disease from an infection-hit suburb.

There have been 173 confirmed cases in New York state, including 108 in Westchester County, home to New Rochelle where the majority of infections have been detected.

"It is a dramatic action, but it is the largest cluster in the country. This is literally a matter of life and death," said state governor Andrew Cuomo.

"People are scared, it's an unusual situation to be in," Miles Goldberg, who runs a New Rochelle bar, told AFP.

"It makes people nervous to be around others, it makes people nervous to get inside into businesses and such," he said.

In an unprecedented move, Italian Prime Minister Giuseppe Conte has told the 60 million residents of his country they should travel only for the most urgent work or health reasons.

And while squares in Milan and Rome were emptied of their usual bustle and traffic, some residents appeared uncertain if they were even allowed to leave their homes for everyday tasks like shopping.

The virus has battered tourism around the world, as people scrap travel plans, and a restaurant owner in Florence in northern Italy said that the impact on business had been catastrophic.

"We hope that we will see the end of it, because from around 140 covers a day, this afternoon, we've gone down to 20-25," Agostino Ferrara told AFP.

Pope Francis also seemed to muddy the waters, holding a mass in which he urged priests to go out and visit the sick -- something Conte has specifically discouraged.

Sporting events continued to fall victim to the virus as authorities urge people to avoid large gatherings.

Arsenal's game at Manchester City was postponed after players from the London club were put into quarantine, making it the first Premier League fixture to be called off because of the virus.

The virus has sparked doubts about the Olympics due to open in Tokyo on July 24 and the traditional flame lighting ceremony in Greece is set to be held without spectators.

In the United States, organisers rescheduled the two-week Coachella music festival for October.

The virus and the response to the crisis has prompted pandemonium on global markets with volatility not seen since the world financial crisis in 2008.

After suffering its worst session in more than 11 years at the beginning of the week, the Dow Jones Index in New York bounced back significantly, rising five percent on Tuesday.

Politicians around the world have scrambled to put together emergency packages to ease the significant financial hardships the virus is expected to cause for households and businesses.

US President Donald Trump, who is relying on a strong economy to boost his re-election hopes, promised to announce "major" economic measures on Tuesday.

The biggest item on his wish list is a cut in payroll taxes. But even allies in Congress and reportedly some aides in the White House are sceptical, questioning the cost.

Italy prepared Tuesday to let families skip mortgage and some tax payments while Japan unveiled a second emergency package to tackle economic woes stemming from the outbreak, including $15 billion in loan programmes to support small businesses.

Analysts warned of further volatility ahead however.

"It's like winding up a rubber band. The more you wind it, when you let go, the more it pops," said LBBW's Karl Haeling.

"A lot of the uncertainty goes to the root of the virus itself."

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News Network
May 24,2020

Beijing, May 24: The Chinese virology institute in the city where COVID-19 first emerged has three live strains of bat coronavirus on-site, but none match the new contagion wreaking chaos across the world, its director has said.

Scientists think COVID-19 -- which first emerged in Wuhan and has killed some 340,000 people worldwide -- originated in bats and could have been transmitted to people via another mammal.

But the director of the Wuhan Institute of Virology told state broadcaster CGTN that claims made by US President Donald Trump and others that the virus could have leaked from the facility were "pure fabrication".

"Now we have three strains of live viruses... But their highest similarity to SARS-CoV-2 only reaches 79.8 percent," she said, referring to the coronavirus strain that causes COVID-19.

US demands immediate start to WHO review

The United States called on the World Health Organisation on Friday to begin working immediately on investigating the source of the novel coronavirus, as well as its handling of the response to the pandemic.

One of their research teams, led by Professor Shi Zhengli, has been researching bat coronaviruses since 2004 and focused on the "source tracing of SARS", the strain behind another virus outbreak nearly two decades ago.

"We know that the whole genome of SARS-CoV-2 is only 80 percent similar to that of SARS. It's an obvious difference," she said.

"So, in Professor Shi's past research, they didn't pay attention to such viruses which are less similar to the SARS virus."

Conspiracy rumours that the biosafety lab was involved in the outbreak swirled online for months before Trump and US Secretary of State Mike Pompeo brought the theory into the mainstream by claiming that there is evidence the pathogen came from the institute.

The lab has said it received samples of the then-unknown virus on December 30, determined the viral genome sequence on January 2 and submitted information on the pathogen to the WHO on January 11.

Wang said in the interview that before it received samples in December, their team had never "encountered, researched or kept the virus."

"In fact, like everyone else, we didn't even know the virus existed," she said. "How could it have leaked from our lab when we never had it?"

The World Health Organization said Washington had offered no evidence to support the "speculative" claims.

In an interview with Scientific American, Shi said the SARS-CoV-2 genome sequence did not match any of the bat coronaviruses her laboratory had previously collected and studied.

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