In a first, scientists map winds in Mars’ upper atmosphere

Agencies
December 14, 2019

Washington, Dec 14: Using data from NASA's MAVEN spacecraft, researchers have created the first-ever map of wind circulation in the upper atmosphere of Mars.

The new map of Mars winds will help scientists to better understand the workings of the Martian climate, giving them a more accurate picture of its ancient past and its ongoing evolution.

"The observed global circulation provides critical inputs needed to constrain global atmospheric models," said Mehdi Benna of NASA's Goddard Space Flight Center in Greenbelt, Maryland.

"These are the same models that are used to extrapolate the state of the Martian climate into the distant past," added Benna in the first paper published in the journal Science.

MAVEN (Mars Atmosphere and Volatile EvolutioN mission) celebrated the five-year anniversary of its entrance into orbit around Mars on September 21.

The primary scientific goal of the mission is to study what is left of Mars' atmosphere to determine how, in the distant past, an ocean-covered and potentially habitable Mars became the dry and desolate place it is today.

"The winds observed in the Martian upper atmosphere are sometimes similar to what we see in global model simulations, but other times can be quite different," said Kali Roeten of University of Michigan.

"These winds can also be highly variable on the timescale of hours, yet in other cases, are consistent throughout the observation period, said Roeten in the second paper published in the Journal of Geophysical Research-Planets.

Upper atmospheric winds on Earth have already been mapped in detail.

Winds drive a series of processes in the atmosphere that can affect the propagation of radio waves, which are crucial for communications purposes for those on the surface, and the prediction of paths satellites will take in their orbit around Earth.

Mapping Martian winds, therefore, is a crucial step towards understanding characteristics of extraterrestrial atmospheres beyond what we know about processes on Earth.

The upper atmospheric winds on both Earth and Mars are in the planets' respective thermospheres, which are areas where temperature increases with height.

This discovery was the first detection of topography-induced gravity wave ripples in the thermosphere of any planet, even Earth.

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Agencies
July 3,2020

Mumbai, Jul 3: In yet another move to keep Chinese technologies companies at bay, the Centre has cancelled the 4G upgradation tender for BSNL as it has decided to come up with fresh specifications for the upgrade process, sources said.

The Department of Telecommunications (DoT) is likely to issue a fresh tender in the next two weeks.

People in the know said that the fresh tender may not allow Chinese companies to participate and that the new tenders that will be floated in the next two weeks will emphasise on Make in India.

As the border tussle with China escalated last month and around 20 soldiers lost their lives, the government had last month asked both BSNL and MTNL not to use equipment of Chinese makers in their upgrading process to 4G facilities.

Huawei and ZTE are the major Chinese telecom equipment makers working with Indian telecom companies and they would be the hardest hit by the decision.

The impact may be felt in terms of the much-awaited 5G trials in the country. After much deliberation, the Centre last December decided to allow Huawei to take part in the 5G trials.

The cancellation of tender for BSNL's 4G upgradation comes after the Centre on Monday banned 59 Chinese apps including TikTok, WeChat and UC Browser.

A statement by the Ministry of Electronics and IT said that the decision was taken since "there is credible information that these apps are engaged in activities which are prejudicial to sovereignty and integrity of India, defence of India, security of state and public order".

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Agencies
February 26,2020

New Delhi, Feb 26: With the government pushing for the disinvestment of Air India, industrial conglomerate Adani Group may emerge as one of the bidders for the debt-laden national carrier, sources said.

According to highly placed sources, the Group has held internal rounds of deliberations on whether or not to submit an Expression of Interest (EoI) and the discussions are still in the preliminary stage.

If the company actually submits an EoI, it would be a major move towards further diversification of the company which has business interests across sectors right from edible oil, food to mining and minerals. 

It also entered into airport operations and maintenance business and won bids for privatisation of six airports, Ahmedabad, Lucknow, Jaipur, Guwahati, Thiruvananthapuram and Mangaluru in 2019. 

On being contacted by IANS, the company did not comment on the matter.

Air India is one of the most important divestment proposals for the current fiscal to reach the huge Rs 2.1 lakh crore target.

The government in January restarted the divestment process of the airline and invited bids for selling 100 per cent of its equity in the state-owned airline, including Air India's 100 per cent shareholding in AI Express Ltd. and 50 per cent in Air India SATS Airport Services Private Ltd.

After its unsuccessful bid to sell Air India in 2018, the government this time has decided to offload its entire stake. In 2018, it had offered to sell its 76 per cent stake in the airline.

Of the total debt of Rs 60,074 crore as of March 31, 2019, the buyer would be required to absorb Rs 23,286 crore.

Air India, along with its subsidiary Air India Express, has a total operational fleet of 146 aeroplanes.

Further, the disinvestment department has extended the last date for submission of written queries on the Performance Information Memorandum and Share Purchase Agreement to March 6.

The last date for submission of written queries on PIM and SPA was originally set for February 11, following which the Department of Investment and Public Asset Management (DIPAM) on February 21 issued 20 clarifications on the queries raised and expected.

Any delay in the tentatively rolled out timeline would also delay DIPAM's plan to identify the pre-qualified bidders by March 31 and the financial bids invitation as well. It is expected to take more than two months after the selection of the pre-qualified bidders to complete Air India's sale.

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News Network
May 7,2020

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.

Follow latest updates on the COVID-19 pandemic here

"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.

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