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
March 28,2020

Washington, Mar 28: A US-based lab has unveiled a portable test that can tell if someone has COVID-19 in as little as five minutes, it said in a statement Friday.

Abbot Laboratories said the US Food and Drug Administration (FDA) had given it emergency authorization to begin making the test available to healthcare providers as early as next week.

The test, which is the size of a small toaster and uses molecular technology, also shows negative results within 13 minutes, the company said in a press statement.

"The COVID-19 pandemic will be fought on multiple fronts, and a portable molecular test that offers results in minutes adds to the broad range of diagnostic solutions needed to combat this virus," said Abbot president and chief operating officer Robert Ford.

The test's small size means it can be deployed outside the "traditional four walls of a hospital in outbreak hotspots," Ford said, and Abbott is working with the FDA to send it to virus epicenters.

The test has not been cleared or approved by the FDA, and has only been authorized for emergency use by approved labs and healthcare providers, the company said.

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News Network
May 6,2020

Singapore, May 6: Oil prices slipped back Wednesday after two days of gains, although Brent crude remained above $30 a barrel, as renewed US-China tensions offset optimism about the easing of coronavirus lockdowns.

Brent, the international benchmark, fell 1.1 per cent to $30.63 a barrel in early Asian trade. On Tuesday, the contract surged 14 per cent and rose above $30 for the first time since mid-April.

US marker West Texas Intermediate slipped 1.9 per cent and was changing hands for $24.13 a barrel.

Oil markets have been battered as the virus strangled demand due to business closures and travel restrictions, with US crude falling into negative territory last month for the first time.

They started rallying strongly this week as countries from Europe to Asia ease curbs and economies start shuddering back to life.

But gains were capped Wednesday as dealers follow a brewing US-China row after Donald Trump hit out at Beijing over its handling of the outbreak, saying it began in a Wuhan lab, but so far offering no evidence.

"Traders are incredibly cautious this morning, weighing all the possible China responses," said Stephen Innes, chief global market strategist at AxiCorp.

"And the one that would hurt the most would be for China to reduce imports of US oil."

This week's rally was in part driven by a deal agreed between top producers to reduce output by almost 10 million barrels a day, which came into effect on May 1.

There have also been signs that the massive oversupply in the market is starting to ease as demand slowly comes back.

Energy data provider Genscape said earlier this week that stockpiles at the main US oil depot in Cushing, Oklahoma had increased by only 1.8 million barrels last week following weeks of major rises.

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Agencies
August 5,2020

Ninety per cent of a sample group of coronavirus-recovered patients from a prominent hospital in China's Wuhan city where the pandemic broke out have reported lung damage and five per cent of them are again in quarantine after testing positive for the virus, according to a media report on Wednesday.

A team at the Zhongnan Hospital of Wuhan University led by Peng Zhiyong, director of the hospital's Intensive Care Unit, has been conducting follow-up visits with '100 recovered patients' since April.

The first phase of this one-year programme finished in July. The average age of the patients in the study is 59.

According to the first phase results, 90 per cent of the patients' lungs are still in a damaged state, which means their lungs ventilation and gas exchange functions have not recovered to the level of healthy people, state-run Global Times reported.

Peng's team conducted a six-minute walking test with the patients. They found that the recovered patients could only walk 400 metres in six minutes while their healthy peers could walk 500 metres in the same period.

Some recovered patients have to rely on oxygen machines even three months after being discharged from the hospital, Liang Tengxiao, a doctor from the Dongzhimen Hospital, Beijing University of Chinese Medicine, was quoted as saying by the report.

Liang's team is also conducting follow-up visits with recovered patients aged above 65.

The results also showed that antibodies against the novel coronavirus in 10 per cent of the 100 patients have disappeared.

Five per cent of them received negative results in Covid-19 nucleic acid tests but positive results in Immunoglobulin M (IgM) tests, and thus have to be quarantined again, the report said.

IgM is usually the first antibody produced by the immune system when a virus attacks. A positive result in an IgM test usually means that a person has just been infected by the virus.

It is still unclear if this means these people have been infected again.

The 100 patients' immune systems have not fully recovered as they showed a low level of B cells -- - a primary force for killing viruses in the human body -- but a high level of T cells which only recognise viral antigens outside infected cells.

"The results revealed that the patients’ immune systems are still recovering," Peng said.

The patients also suffered from depression and a sense of stigma. Most of the recovered patients told the team that their families were not willing to have dinner with them at the same table, the report said.

Less than half of the recovered patients have returned to work, it said.

The findings are significant as the coronavirus first emerged in Wuhan city.

Hubei province for which Wuhan is the provincial capital has reported a total of 68,138 confirmed Covid-19 cases till now. The disease has claimed 4,512 lives in the province, according to the official data.

China reported 27 new confirmed Covid-19 cases on Tuesday, including 22 locally-transmitted cases, the National Health Commission (NHC) said on Wednesday.

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