2 SpiceJet pilots suspended for improper landing at Mangaluru Airport

The current physical distancing guidelines provided by the World Health Organisation (WHO) and by the US Centers for Disease Control and Prevention (CDC) may not be adequate to curb the coronavirus spread, according to a research which says the gas cloud from a cough or sneeze may help virus particles travel up to 8 metres. The research, published in the Journal of the American Medical Association, noted that the the current guidelines issued by the WHO and CDC are based on outdated models from the 1930s of how gas clouds from a cough, sneeze, or exhalation spread.

Study author, MIT associate professor Lydia Bourouiba, warned that droplets of all sizes can travel 23 to 27 feet, or 7-8 metres, carrying the pathogen.

According to Bourouiba, the current guidelines are based on "arbitrary" assumptions of droplet size, "overly simplified", and "may limit the effectiveness of the proposed interventions" against the deadly pandemic.

 She explained that the old guidelines assume droplets to be one of two categories, small or large, taking short-range semi-ballistic trajectories when a person exhales, coughs, or sneezes.

However based on more recent discoveries, the MIT scientist said, sneezes and coughs are made of a puff cloud that carries ambient air, transporting within it clusters of droplets of a wide range of sizes.

Bourouiba warned that this puff cloud, with ambient air entrapped in it, can offer the droplets moisture and warmth that can prevent it from evaporation in the outer environment.

"The locally moist and warm atmosphere within the turbulent gas cloud allows the contained droplets to evade evaporation for much longer than occurs with isolated droplets," she said.

"Under these conditions, the lifetime of a droplet could be considerably extended by a factor of up to 1000, from a fraction of a second to minutes," the researcher explained in the study.

The MIT scientist, who has researched the dynamics of coughs and sneezes for years, added that these droplets settle along the trajectory of a cough or sneeze contaminating surfaces, with their residues staying suspended in the air for hours.

"Even when maximum containment policies were enforced, the rapid international spread of COVID-19 suggests that using arbitrary droplet size cutoffs may not accurately reflect what actually occurs with respiratory emissions, possibly contributing to the ineffectiveness of some procedures used to limit the spread of respiratory disease," Bourouiba wrote in the study

The euphoria over the claim that around 3,000 tonnes of gold reserves, worth Rs 12 trillion, have been discovered in Uttar Pradesh’s Sonbhadra district could not last even 24 hours, with the Geological Survey of India (GSI) clarifying on Saturday there had been no such discovery.

The GSI, headquartered in Kolkata, rebutted the claims of the Uttar Pradesh Directorate of Geology and Mining (UPDGM), and said “miscommunication” must have led to the wrong reporting of facts.

M Sridhar, director general of the GSI, said nobody in the agency gave any such data. He said 52,806 tonnes of gold ore was found in Sonbhadra district during the exploration work in 1998-2000. From this reserve, only 160 kg of gold can be extracted.

“There must have been some miscommunication of facts because of which the gold ore deposits have been overestimated. We have written a letter to Uttar Pradesh (UPDGM), stating the facts. The GSI has not estimated such kind of vast resource of gold deposits in Sonbhadra,” Sridhar said.

ALSO READ: 2,900-tonne gold mine found in Sonbhadra, 4 times that of India's reserves

The UPDGM had said on Friday that gold deposits were found in Son Pahadi and Hardi areas of the district. Sridhar said while gold ore was found in the area during the GSI’s exploration work in 1998-2000, it had told the state government about the discovery in November last year.

Under the new regulation, which came into effect from 2015, the GSI has to inform the state government when ore deposits are discovered. Earlier, no such action was mandatory. In its report, the GSI estimated that only 3.03 gm of gold can be extracted from a tonne of ore. It also clarified that even the extraction amount was tentative and could not be established for certain.

Moreover, Sridhar said the deposits were spread across only 0.5 sq km in forest land, which made the mining of ore economically unviable. “When there are several mines nearby, we can club it into a block and then it makes sense to mine the ore. But in this case, the deposits are too small to make it viable for any company to mine it,” he said. The GSI usually prioritises its exploration work based on the needs of the Centre. While strategic minerals like tin, cobalt, lithium, beryllium, germanium, gallium, indium, tantalum, niobium, selenium, and bismuth are atop the list in GSI exploration, gold is another commodity on its priority list.

According to the World Gold Council, India has reserves of 630 tonnes of gold.