Bangladesh Votes Today, Sheikh Hasina Seeks Fourth Term as Prime Minister

London, May 20: The current physical distancing guidelines of 6 feet may be insufficient to prevent COVID-19 transmission, according to a study which says a mild cough in low wind speeds can propel saliva droplets by as much as 18 feet.

Researchers, including those from the University of Nicosia in Cyprus, said a good baseline for studying the airborne transmission of viruses, like the one behind the COVID-19 pandemic, is a deeper understanding of how particles travel through the air when people cough.

In the study, published in the journal Physics of Fluids, they said even with a slight breeze of about four kilometres per hour (kph), saliva travels 18 feet in 5 seconds.

"The droplet cloud will affect both adults and children of different heights," said study co-author Dimitris Drikakis from the University of Nicosia.

According to the scientists, shorter adults and children could be at higher risk if they are located within the trajectory of the saliva droplets.

They said saliva is a complex fluid, which travels suspended in a bulk of surrounding air released by a cough, adding that many factors affect how saliva droplets travel in the air.

These factors, the study noted, include the size and number of droplets, how they interact with one another and the surrounding air as they disperse and evaporate, how heat and mass are transferred, and the humidity and temperature of the surrounding air.

In the study, the scientists created a computer simulation to examine the state of every saliva droplet moving through the air in front of a coughing person.

The model considered the effects of humidity, dispersion force, interactions of molecules of saliva and air, and how the droplets change from liquid to vapour and evaporate, along with a grid representing the space in front of a coughing person.

Each grid, the scientists said, holds information about variables like pressure, fluid velocity, temperature, droplet mass, and droplet position.

The study analysed the fates of nearly 1,008 simulated saliva droplets, and solved as many as 3.7 million equations.

"The purpose of the mathematical modelling and simulation is to take into account all the real coupling or interaction mechanisms that may take place between the main bulk fluid flow and the saliva droplets, and between the saliva droplets themselves," explained Talib Dbouk, another co-author of the study.

However, the researchers added that further studies are needed to determine the effect of ground surface temperature on the behaviour of saliva in air.

They also believe that indoor environments, especially ones with air conditioning, may significantly affect the particle movement through air.

This work is important since it concerns safety distance guidelines, and advances the understanding of the transmission of airborne diseases, Drikakis said.

Jun 27: Alittle-known Indian IT firm offered its hacking services to help clients spy on more than 10,000 email accounts over a period of seven years.

New Delhi-based BellTroX InfoTech Services targeted government officials in Europe, gambling tycoons in the Bahamas, and well-known investors in the United States including private equity giant KKR and short seller Muddy Waters, according to three former employees, outside researchers, and a trail of online evidence.

Aspects of BellTroX's hacking spree aimed at American targets are currently under investigation by U.S. law enforcement, five people familiar with the matter told Reuters. The U.S. Department of Justice declined to comment.

Reuters does not know the identity of BellTroX's clients. In a telephone interview, the company's owner, Sumit Gupta, declined to disclose who had hired him and denied any wrongdoing.

Muddy Waters founder Carson Block said he was "disappointed, but not surprised, to learn that we were likely targeted for hacking by a client of BellTroX." KKR declined to comment.

Researchers at internet watchdog group Citizen Lab, who spent more than two years mapping out the infrastructure used by the hackers, released a report that BellTroX employees were behind the espionage campaign.

"This is one of the largest spy-for-hire operations ever exposed," said Citizen Lab researcher John Scott-Railton.

Although they receive a fraction of the attention devoted to state-sponsored espionage groups or headline-grabbing heists, "cyber mercenary" services are widely used, he said. "Our investigation found that no sector is immune."

A cache of data reviewed by Reuters provides insight into the operation, detailing tens of thousands of malicious messages designed to trick victims into giving up their passwords that were sent by BellTroX between 2013 and 2020. The data was supplied on condition of anonymity by online service providers used by the hackers after Reuters alerted the firms to unusual patterns of activity on their platforms.

The data is effectively a digital hit list showing who was targeted and when. Reuters validated the data by checking it against emails received by the targets.

On the list: judges in South Africa, politicians in Mexico, lawyers in France and environmental groups in the United States. These dozens of people, among the thousands targeted by BellTroX, did not respond to messages or declined comment.

Reuters was not able to establish how many of the hacking attempts were successful.

BellTroX's Gupta was charged in a 2015 hacking case in which two U.S. private investigators admitted to paying him to hack the accounts of marketing executives. Gupta was declared a fugitive in 2017, although the U.S. Justice Department declined to comment on the current status of the case or whether an extradition request had been issued.

Speaking by phone from his home in New Delhi, Gupta denied hacking and said he had never been contacted by law enforcement. He said he had only ever helped private investigators download messages from email inboxes after they provided him with login details.

"I didn't help them access anything, I just helped them with downloading the mails and they provided me all the details," he told Reuters. "I am not aware how they got these details but I was just helping them with the technical support."

Reuters could not determine why the private investigators might need Gupta to download emails. Gupta did not return follow-up messages. Spokesmen for Delhi police and India's foreign ministry did not respond to requests for comment.

HOROSCOPES AND PORNOGRAPHY

Operating from a small room above a shuttered tea stall in a west-Delhi retail complex, BellTroX bombarded its targets with tens of thousands of malicious emails, according to the data reviewed by Reuters. Some messages would imitate colleagues or relatives; others posed as Facebook login requests or graphic notifications to unsubscribe from pornography websites.

Fahmi Quadir's New York-based short selling firm Safkhet Capital was among 17 investment companies targeted by BellTroX between 2017 and 2019. She said she noticed a surge in suspicious emails in early 2018, shortly after she launched her fund.

Initially "it didn't seem necessarily malicious," Quadir said. "It was just horoscopes; then it escalated to pornography."

Eventually the hackers upped their game, sending her credible-sounding messages that looked like they came from her coworkers, other short sellers or members of her family. "They were even trying to emulate my sister," Quadir said, adding that she believes the attacks were unsuccessful.

U.S. advocacy groups were also repeatedly targeted. Among them were digital rights organizations Free Press and Fight for the Future, both of whom have lobbied for net neutrality. The groups said a small number of employee accounts were compromised, but the wider organizations' networks were untouched. The spying on those groups was detailed in a report by the Electronic Frontier Foundation in 2017, but has not been publicly tied to BellTroX until now.

Timothy Karr, a director at Free Press, said his organization "sees an uptick in breach attempts whenever we're engaged in heated and high-profile public policy debates." Evan Greer, deputy director of Fight for the Future, said: "When corporations and politicians can hire digital mercenaries to target civil society advocates, it undermines our democratic process."

While Reuters was not able to establish who hired BellTroX to carry out the hacking, two former employees said the company and others like it were usually contracted by private investigators on behalf of business rivals or political opponents.

Bart Santos of San Diego-based Bulldog Investigations was one of a dozen private detectives in the United States and Europe who told Reuters they had received unsolicited advertisements for hacking services out of India - including one from a person who described himself as a former BellTroX employee. The pitch offered to carry out "data penetration" and "email penetration."

Santos said he ignored those overtures, but could understand why some people didn't. "The Indian guys have a reputation for customer service," he said.

Seoul, Jun 24: North Korea on Wednesday said leader Kim Jong Un suspended a planned military retaliation against South Korea, possibly slowing the pressure campaign it has waged against its rival amid stalled nuclear negotiations with the Trump administration.

Last week, the North had declared relations with the South as fully ruptured, destroyed an inter-Korean liaison office in its territory and threatened unspecified military action to censure Seoul for a lack of progress in bilateral cooperation and for activists floating anti-Pyongyang leaflets across the border.

Analysts say North Korea, after weeks deliberately raising tensions, may be pulling away just enough to make room for South Korean concessions.

Pyongyang's official Korean Central News Agency said Kim presided by video conference over a meeting Tuesday of the ruling Workers' Party's Central Military Commission, which decided to postpone plans for military action against the South brought up by the North's military leaders.

KCNA didn't specify why the decision was made. It said other discussions included bolstering the country's "war deterrent".

Yoh Sang-key, spokesman of South Korea's Unification Ministry, said Seoul was "closely reviewing" the North's report but didn't further elaborate.

Yoh also said it was the first report in state media of Kim holding a video conferencing meeting, but he didn't provide a specific answer when asked whether that would have something to do with the coronavirus.

The North says there hasn't been a single COVID-19 case on its territory, but the claim is questioned by outside experts.

Kim Dong-yub, an analyst from Seoul's Institute for Far Eastern Studies, said it's likely that the North is waiting for further action from the South to salvage ties from what it sees as a position of strength, rather than softening its stance on its rival.

"What's clear is that the North said (the military action) was postponed, not cancelled," said Kim, a former South Korean military official who participated in inter-Korean military negotiations.

Other experts say the North would be seeking something major from the South, possibly a commitment to resume operations at a shuttered joint factory park in Kaesong, which was where the liaison office was located, or restart South Korean tours to the North's Diamond Mountain resort.

Those steps are prohibited by the international sanctions against the North over its nuclear weapons programme.

The public face of the North's recent bashing of the South has been Kim Yo Jong, the powerful sister of leader Kim Jong Un, who has been confirmed as his top official on inter-Korean affairs.

Issuing harsh statements through state media, she had said the North's demolishing of the liaison office would be just the first in a series of retaliatory action against the enemy South and that she would leave it to the North's military to come up with the next steps.

The General Staff of the North's military has said it would send troops to the mothballed inter-Korean cooperation sites in Kaesong and Diamond Mountain and restart military drills in frontline areas.

Such steps would nullify a set of deals the Koreas reached during a flurry of diplomacy in 2018 that prohibited them from taking hostile action against each other.

Also condemning the South over North Korean refugees floating anti-Pyongyang leaflets across the border, the North said Monday it printed 12 million of its own propaganda leaflets to be dropped over the South in what would be its largest ever anti-Seoul leafleting campaign.

It wasn't immediately clear whether Kim's decision to hold back military action would affect the country's plans for leafleting. The North's military had said it would open border areas on land and sea and provide protection for civilians involved in the leafleting campaigns.

The North has a history of dialling up pressure against the South when it fails to get what it wants from the United States. The North's recent steps came after months of frustration over Seoul's unwillingness to defy US-led sanctions and restart the inter-Korean economic projects that would breathe life into its broken economy.

Nuclear negotiations between Pyongyang and Washington largely stalled after Kim's second summit with President Donald Trump last year in Vietnam, where the Americans rejected North Korea's demands for major sanctions relief in exchange for a partial surrender of its nuclear capabilities.