Hope triple talaq bill becomes a law soon: President Kovind

Washington DC, Jun 8: Astronomers acting on a hunch have likely resolved a mystery about young, still-forming stars and regions rich in organic molecules closely surrounding some of them.

They used the National Science Foundation's Karl G Jansky Very Large Array (VLA) to reveal one such region that previously had eluded detection and that revelation answered a longstanding question.

The regions around the young protostars contain complex organic molecules which can further combine into prebiotic molecules that are the first steps on the road to life.

The regions, dubbed "hot corinos" by astronomers, are typically about the size of our solar system and are much warmer than their surroundings, though still quite cold by terrestrial standards.

The first hot corino was discovered in 2003 and only about a dozen have been found so far. Most of these are in binary systems, with two protostars forming simultaneously.

Astronomers have been puzzled by the fact that, in some of these binary systems, they found evidence for a hot corino around one of the protostars but not the other.

"Since the two stars are forming from the same molecular cloud and at the same time, it seemed strange that one would be surrounded by a dense region of complex organic molecules and the other wouldn't," said Cecilia Ceccarelli, of the Institute for Planetary Sciences and Astrophysics at the University of Grenoble (IPAG) in France.

The complex organic molecules were found by detecting specific radio frequencies, called spectral lines, emitted by the molecules. Those characteristic radio frequencies serve as "fingerprints" to identify the chemicals.

The astronomers noted that all the chemicals found in hot corinos had been found by detecting these "fingerprints" at radio frequencies corresponding to wavelengths of only a few millimetres.

"We know that dust blocks those wavelengths, so we decided to look for evidence of these chemicals at longer wavelengths that can easily pass through dust," said Claire Chandler of the National Radio Astronomy Observatory, and principal investigator on the project.

"It struck us that dust might be what was preventing us from detecting the molecules in one of the twin protostars," added Chandler.

The astronomers used the VLA to observe a pair of protostars called IRAS 4A, in a star-forming region about 1,000 light-years from Earth. They observed the pair at wavelengths of centimetres.

At those wavelengths, they sought radio emissions from methanol, CH3OH (wood alcohol, not for drinking). This was a pair in which one protostar clearly had a hot corino and the other did not, as seen using the much shorter wavelengths.

The result confirmed their hunch. "With the VLA, both protostars showed strong evidence of methanol surrounding them. This means that both protostars have hot corinos. The reason we did not see the one at shorter wavelengths was because of dust," said Marta de Simone, a graduate student at IPAG who led the data analysis for this object.

The astronomers cautioned that while both hot corinos now are known to contain methanol, there still may be some chemical differences between them. That, they said, can be settled by looking for other molecules at wavelengths not obscured by dust.

"This result tells us that using centimetre radio wavelengths is necessary to properly study hot corinos," Claudio Codella of Arcetri Astrophysical Observatory in Florence, Italy, said.

"In the future, planned new telescopes such as the next-generation VLA and SKA, will be very important to understanding these objects," added Codella.

New Delhi, Jun 18: Vodafone Idea on Thursday told the Supreme Court that it has incurred Rs 1 lakh crore losses as it insisted it is not in a position to furnish bank guarantees.

A bench comprising Justices Arun Mishra, S. Abdul Nazeer, and M.R. Shah, taking up the adjusted gross revenue (AGR) matter through video conferencing, directed the telecom companies to submit their financial documents and books for the last 10 years.

Asking Vodafone if it was a foreign company, the bench said that how can the company say it would not furnish any bank guarantee.

"What if you fly away overnight in future without paying anything?" it asked.

Senior advocate Mukul Rohatgi, representing Vodafone Idea, denied his client is a completely foreign firm and cited before the bench its tie-ups and investments.

Vodafone owes over Rs 58,000 crore as AGR dues and so far, has paid close to Rs 7,000 crore.

Rohatgi contended before the court that the telecom company is in a tough situation, and cannot furnish any fresh bank guarantee, as profits have eluded the company in past many quarters. He submitted before the bench that Rs 15,000 crore bank guarantees are lying with the government, and his client's losses are over Rs 1 lakh crore.

"I cannot offer any more surety," he informed the bench.

Justice Mishra noted that this is public money and these dues should be recovered. "Do not tell us that you will pay if you were to make profits... the money must come," he noted.

Justice Shah observed that the telecom industry is the only industry which earned during the Covid-19 pandemic. "After all, this money will be used for public welfare", he said.

Rohatgi argued that his client would have to fold up if orders were issued to clear dues tomorrow. "11,000 employees will have to go without notice, as we cannot pay them," he added.

Senior advocate Abhishek Manu Singhvi, appearing for Bharti Airtel, contended before the court that out of Rs 21,000 crore AGR dues, the company has already deposited a sum of Rs 18,000 crore.

He argued that his client has given a bank guarantee, in excess of demand, to DoT, and supported the proposal for phased repayment of remaining AGR dues. He insisted that the company needs to sit down with the government and calculate the dues. Airtel owes Rs 25,976 crore after paying Rs 18,000 crore, as per the government.

Senior advocate Arvind Datar, representing Tata Telecom, informed the bench that his client has paid Rs 6,504 crore in AGR dues so far, and furnishing a bank guarantee may adversely impact investments in the sector.

The total AGR dues are close to Rs 1.5 lakh crore.

The top court will now take up the matter in the third week of July.

Melbourne, Jul 24: Home-made cloth face masks may need a minimum of two layers, and preferably three, to prevent the dispersal of viral droplets associated with Covid-19, according to a study.

Researchers, including those from the University of New South Wales in Australia, noted that viral droplets are generated by those infected with the novel coronavirus when they cough, sneeze, or speak.

As face masks have been proven to protect healthy people from inhaling infectious droplets as well as reducing the spread from those who are already infected, several types of material have been suggested for these, but based on little or no evidence of how well they work, the scientists said.

In the current study, published in the journal Thorax, the researchers compared the effectiveness of single and double-layer cloth face coverings with a surgical face mask (Bao Thach) at reducing droplet spread.

They said the single layer covering was made from a folded piece of cotton T shirt and hair ties, and the double layer covering was made using the sew method described by the US Centers for Disease Control and Prevention (CDC).

The scientists used a tailored LED lighting system and a high-speed camera to film the dispersal of airborne droplets produced by a healthy person with no respiratory infection, during speaking, coughing, and sneezing while wearing each type of mask.

Their analysis showed that the surgical face mask was the most effective at reducing airborne droplet dispersal, although even a single layer cloth face covering reduced the droplet spread from speaking.

But the study noted that a double layer covering was better than a single layer in reducing the droplet spread from coughing and sneezing.

According to the researchers, the effectiveness of cloth face masks is dependent on the number of layers of the covering, the type of material used, design, fit as well as the frequency of washing.

Based on their observations, they said a home made cloth mask with at least two layers is preferable to a single layer mask.

"Guidelines on home-made cloth masks should stipulate multiple layers," the scientists said, adding that there is a need for more research to inform safer cloth mask design.