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
June 4,2020

Jun 4: A malaria drug President Donald Trump took to try to prevent COVID-19 proved ineffective for that in the first large, high-quality study to test it in people in close contact with someone with the disease.

Results published Wednesday by the New England Journal of Medicine show that hydroxychloroquine was no better than placebo pills at preventing illness from the coronavirus.

The drug did not seem to cause serious harm, though -- about 40% on it had side effects, mostly mild stomach problems.

 “We were disappointed. We would have liked for this to work,” said the study leader, Dr. David Boulware, an infectious disease specialist at the University of Minnesota.

“But our objective was to answer the question and to conduct a high-quality study,” because the evidence on the drug so far has been inconclusive, he said.

Hydroxychloroquine and a similar drug, chloroquine, have been the subject of much debate since Trump started promoting them in March.

Hydroxychloroquine has long been used for malaria, lupus, and rheumatoid arthritis, but no large studies have shown it or chloroquine to be safe or effective for much sicker patients with coronavirus, and some studies have suggested the drugs may do harm.

Trump took a two-week course of hydroxychloroquine, along with zinc and Vitamin D, after two staffers tested positive for COVID-19, and had no ill effects, according to results of his latest physical released by his doctor Wednesday.

Federal regulators have warned against hydroxychloroquine's use except in hospitals and formal studies because of the risk of side effects, especially heart rhythm problems.

Boulware's study involved 821 people in the United States and Canada living with someone diagnosed with COVID-19 or at high risk of getting it because of their job -- doctors, nurses, ambulance workers who had significant exposure to a sick patient while not wearing full protective gear.

They were randomly assigned to get either the nutrient folate as a placebo or hydroxychloroquine for five days, starting within four days of their exposure. Neither they nor others involved in the research knew who was getting which pills.

After 14 days in the study, 12 per cent on the drug developed COVID-19 symptoms versus 14 per cent in the placebo group, but the difference is so small it could have occurred by chance, Boulware said.

“There's basically no effect. It does not prevent infection,” he said of the drug. Even if it were to give some slim advantage, “we'd want a much larger effect” to justify its use and risk of side effects for preventing illness, he said.

Results were no different among a subgroup of participants who were taking zinc or vitamin C, which some people believe might help make hydroxychloroquine more effective or fight the coronavirus.

There are some big caveats: The study enrolled people through the Internet and social media, relying on them to report their own symptoms rather than having them tracked in a formal way by doctors.

Participants were not all tested for the coronavirus but were diagnosed as COVID-19 cases based on symptoms in many cases. And not all took their medicines as directed.

The results “are more provocative than definitive,” and the drug may yet have prevention benefits if tried sooner or in a different way, Dr. Myron Cohen of the University of North Carolina at Chapel Hill wrote in a commentary in the journal.

Others were glad to see a study that had a comparison group and good scientific methods after so many weaker reports on hydroxychloroquine.

“This fits with everything else we've seen so far which suggests that it's not beneficial," said Dr. Peter Bach, director of a health policy center at Memorial Sloan Kettering Cancer Center in New York.

This study was in younger relatively healthy people, but the results “would make me very discouraged about trying to use this in older people” who are most vulnerable to serious illness from the coronavirus, Bach said.

“If it does work, it doesn't work very well.” Dr. Dan Culver, a lung specialist at the Cleveland Clinic, said there's still a chance that giving the drug sooner than four days after someone's exposure to the virus may help prevent illness.

But the study “takes 'home run' off the table” as far as hopes for the drug, he said.

The study was mostly funded by David Baszucki, founder of Roblox, a California-based game software company, and other private donors and the Minnesota university.

Boulware also is leading a study testing hydroxychloroquine for treating COVID-19. The study is finished and results are being analyzed now.

On Tuesday, the journal Lancet posted an “expression of concern” about a study it published earlier this month of nearly 15,000 COVID-19 patients on the malaria drugs that tied their use to a higher risk of dying in the hospital or developing a heartbeat problem.

Scientists have raised serious questions about the database used for that study, and its authors have launched an independent audit.

That work had a big impact: the World Health Organization suspended use of hydroxychloroquine in a study it is leading, and French officials stopped the drug's use in hospitals. On Wednesday, the WHO said experts who reviewed safety information decided that its study could resume.

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Agencies
March 1,2020

Washington, Mar 1: The US Federal Communications Commission (FCC) has proposed a fine of over $200 million for all major US mobile carriers for selling the location data of customers to some agencies.

The Federal Communications Commission today proposed fines against the nation's four largest wireless carriers for apparently selling access to their customers' location information without taking reasonable measures to protect against unauthorised access to that information. As a result, T-Mobile faces a proposed fine of more than $91 million, AT&T faces a proposed fine of more than $57 million, Verizon faces a proposed fine of more than $48 million, and Sprint faces a proposed fine of more than $12 million, the FCC said in a statement on Friday.

The Enforcement Bureau of FCC opened this investigation after reports surfaced that a Missouri Sheriff, Cory Hutcheson, used a "location-finding service" operated by Securus, a provider of communications services to correctional facilities, to access the location information of the wireless carriers' customers without their consent between 2014 and 2017.

"American consumers take their wireless phones with them wherever they go. And information about a wireless customer's location is highly personal and sensitive. The FCC has long had clear rules on the books requiring all phone companies to protect their customers' personal information. And since 2007, these companies have been on notice that they must take reasonable precautions to safeguard this data and that the FCC will take strong enforcement action if they don't. Today, we do just that," said FCC Chairman Ajit Pai.

"This FCC will not tolerate phone companies putting Americans' privacy at risk."

The FCC also admonished these carriers for apparently disclosing their customers' location information, without their authorisation, to a third party

The four major US carriers mentioned sold access to their customers' location information to "aggregators," who then resold access to such information to third-party location-based service providers (like Securus).

Although their exact practices varied, each carrier relied heavily on contract-based assurances that the location-based services providers (acting on the carriers' behalf) would obtain consent from the wireless carrier's customer before accessing that customer's location information.

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News Network
May 6,2020

May 6: In a first, a Pakistani Hindu youth has become the first person from the minority community to join the Pakistan Air Force.

Rahul Dev has been recruited as a General Duty Pilot Officer, the Pakistan Air Force (PAF) said in a tweet.

Dev hails from Tharparkar district of Sindh province.

Sharing the picture of the young man, the PAF recently tweeted, "Good news during #COVID19 tense situation. Thar rocked again...Congratulations #RahulDev who hails from very remote village of Tharparkar has been selected as GD Pilot in #PAF."

Though Dev's exact age is not known, those inducted in PAF at his level are often around 20.

The official Radio Pakistan on Wednesday said it is "for the first time in Pakistan's history" that a Hindu youth has been recruited as a general duty pilot officer in PAF.

The Express Tribune in a report published on Wednesday said the induction showed that the PAF was breaking barriers.

Last year, Kainat Junaid became the first woman from Khyber-Pakthunkhwa province to have been selected for fighter pilot training.

Junaid not only secured the top position in PAF's test for General Duty Pilot, but also became Pakistan’s first female fighter pilot to serve the country alongside her father.

Her father Ahmed Junaid is a Squadron Leader in the PAF.

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