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COVID-19 can be spread by building ventilation, say Canadian researchers working on an HVAC fix – St. Thomas Times-Journal

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A group of Alberta researchers are working on ways that buildings could change their HVAC set-ups to curb the risk of infection

An African restaurant is closed off along with other businesses in Guangzhou’s Sanyuanli area, where a neighborhood is in lockdown after several people tested positive for the novel coronavirus disease (COVID-19), in Guangdong province, China April 13, 2020.

REUTERS/David Kirton

The outbreak of COVID-19 at a restaurant in the southern Chinese city of Guangzhou was a puzzle.

The suspected index patient was a visitor from the coronavirus’s epicentre in Wuhan. But the eight other customers who later tested positive were not sitting close enough for droplet transmission, and most of the patrons and staff avoided infection altogether.

A team of local scientists eventually came to an eye-opening conclusion about the episode: tiny particles of virus had hitched a ride on currents created by the eatery’s air-conditioning.

That runs counter to the prevailing view that the novel coronavirus is transmitted only by heavier “droplets.” But for a group of civil engineers at the University of Alberta, the finding was no surprise. In their world, they say, it’s well known that building ventilation systems are efficient disseminators of viruses and other pathogens, and they believe the COVID-19 bug is no exception.

Aided by a $440,000 federal-government grant, they’re now working on ways that buildings could change their HVAC set-ups to curb the risk of infection, what the researchers call a “non-pharmaceutical” intervention against the disease.

We want to save lives, let’s cut right to the chase

“We want to save lives, let’s cut right to the chase,” said Prof. Brian Fleck, part of the project. “There are so many, many, many buildings … This affects absolutely everybody. Billions of people. If we are able to cut down the transmission rate by a per cent, that’s a lot of people.”

The engineers’ belief in the importance of building ventilation as a transmitter of the COVID-19 virus is not universally held.

The World Health Organization and other public-health bodies, citing the science to date, say the pathogen is spread almost entirely by droplets, heavier particles emitted mostly when infected people cough or sneeze, and which fall down within a short distance. Hence the two-metre rule for social distancing, and the emphasis on washing hands after touching surfaces where virus may have alighted.

“The HVAC systems in most non-medical buildings play only a small role in infectious disease transmission, including COVID-19,” argued the American Society of Heating, Refrigerating, and Air-Conditioning Engineers last month.

It’s just smaller and lighter aerosol particles that can spread through a ventilation system and “the truth is that we still don’t really know if the (COVID-19) virus can be spread by aerosols,” said Matthew Miller, a virus expert at McMaster University in Hamilton.

But Chinese and Australian air-quality experts, citing in part the experience with SARS, another coronavirus, argued in a paper earlier this month that as droplets from an infected person start to evaporate, the resulting smaller particles can indeed become airborne.

They point to evidence that passengers confined to their cabins on cruise ships like the Diamond Princess may have been infected through the vessels’ air ducts.

“It is highly likely that the SARS-CoV-2 virus also spreads by air,” they conclude, urging “all possible” action in response, including modifications to ventilation systems. “We predict that … failure to immediately recognize and acknowledge the importance of airborne transmission and to take adequate actions against it will result in additional cases.”

Then there was the Guangzhou restaurant case, detailed in a U.S. Centers for Disease Control online journal recently. Researchers concluded flow from an air conditioner moved over three tables, carrying virus from the infected patron at the middle one to the far table, then back to the diners closest to the air conditioner.

Even if it turned out SARS-CoV-2 does not spread that way, influenza viruses can, and the University of Alberta research would be valuable for that reason alone, said Miller.

Heating, ventilation and air conditioning (HVAC) engineers have long known that tiny particles of pathogen travel in the air that is circulated, heated and cooled in modern buildings, said Fleck. He pointed to Legionnaires disease, a bacterial pneumonia first traced to a hotel’s air-conditioning system.

The particle can stay airborne long enough to go all the way through the system and then pop out in somebody else’s office

“This has been on people’s radar for quite a while,” he said. “Somebody on a different floor sneezes …The particle can stay airborne long enough to go all the way through the system and then pop out in somebody else’s office.”

There are various ways that the risk can be lessened, including use of filters that catch a greater number of those particles, and drawing more fresh air into a system. It also is likely that higher levels of humidity – a factor that only some Canadian buildings can adjust – will help kill off the virus, said Fleck.

But each of those changes carries a cost. Adding more fresh air can require additional heat or air conditioning. Heavier filters means more energy is needed to push the air through them. And more humidity can lead to mould, he noted.

“This will make for difficult decision making.”

Funded by the Canadian Institute for Health Research, the University of Alberta project is led by engineering professor Lexuan Zhong and also involves pediatrics professor Lisa Hartling. It consists of three phases: systematically reviewing literature on air circulation and viruses, determining what strategies would be effective and then carrying out a detailed audit of all the buildings on the Edmonton campus to create a real-world model of what should be done.

The team hopes to have solid results by the summer of 2021, said Fleck.

(Modified 12:40 April 26 to add comments by Matthew Miller.)

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A 2020 space oddity? Mysterious metal object found in Utah desert – cjoy.com

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A mysterious slab of metal stands silently in the desert, leaving Earth’s primates puzzled.

That’s how the Stanley Kubrick film 2001: A Space Odyssey begins. It’s also the way things are playing out in Utah in 2020, after biologists made a baffling discovery in the state’s southern desert.

Read more:
Famous alien-hunting telescope shut down to avoid ‘catastrophic failure’

State wildlife officials say they were counting bighorn sheep from a helicopter last Wednesday when they stumbled upon a mysterious slab of metal sticking up out of the rock. The object stood 3-3.7 metres tall and appeared to be completely solid and undecorated, according to a crew from the Utah Department of Public Safety and the Utah Division of Wildlife Resources.

Its true origin is unknown.

“One of the biologists is the one who spotted it and we just happened to fly directly over the top of it,” helicopter pilot Bret Hutchings told Utah broadcaster KSLTV.

Read more:
Mysterious radio signal from space traced to ‘zombie’ in our galaxy

Hutchings and the crew of biologists touched down nearby and ventured down into a red-rock cove to examine the object up close.

Video shows it’s a solid piece of metal standing as tall as two humans.

“The intrepid explorers go down to investigate the alien life form,” one crew member said with a chuckle, in video they later provided to KSLTV.

Hutchings says the group had some fun with the discovery, though they still don’t know exactly they’re dealing with.

“We were joking around that if one of us suddenly disappears, I guess the rest of us make a run for it,” Hutchings said.

The object appeared to have been planted in place and likely did not fall into position from above, Hutchings said.

State officials did not indicate exactly where they found the monolith because it was in a remote area that is dangerous for hikers. They say they’d rather not inspire amateur adventurers to go out looking for it in hopes of solving the mystery.

Read more:
‘Hell’ planet found with lava oceans, rocky rain and supersonic winds

“That’s been about the strangest thing that I’ve come across out there in all my years of flying,” Hutchings said.

He added that the object is probably an art installation or a tribute to Kubrick’s film.

The opening scene of 2001: A Space Odyssey depicts a race of ape-like human ancestors who swarm over a mysterious slab of metal that suddenly appears in their rocky home. One of the apes learns how to use tools a short time after the object appears.

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No members of the helicopter crew have reported any incredible scientific discoveries to date, but that hasn’t stopped people from speculating about the object’s origin.

The Utah Highway Patrol encouraged followers to guess about the object’s purpose, triggering a slew of guesses about aliens, wormholes, interdimensional portals and Kubrick’s film.

Many users called for the object to be left alone, if only to avoid any further misfortunes during a historically weird 2020.

“If I were y’all I’d wait until at least 2021, maybe 2022 for good measure, before touching it,” one user wrote.

“PUT IT BACK!” another user wrote. “We’ve had enough surprises this year.”

© 2020 Global News, a division of Corus Entertainment Inc.

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Scientists produce diamonds in minutes at room temperature – MINING.com

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“Natural diamonds are usually formed over billions of years, about 150 kilometres deep in the Earth where there are high pressures and temperatures above 1,000 degrees Celsius,”  Jodie Bradby, professor at The Australian National University and one of the authors of the study, said in a media statement.

“The twist in this story is how we apply the pressure. As well as very high pressures, we allow the carbon to also experience something called ‘shear’ – which is like a twisting or sliding force. We think this allows the carbon atoms to move into place and form Lonsdaleite and regular diamond.” 

The RMIT team’s pictures showed that the regular diamonds only form in the middle of these Lonsdaleite veins under this new method. (Image courtesy of the Royal Melbourne Institute of Technology).

To observe and understand how this process works, the researchers used advanced electron microscopy techniques to capture solid and intact slices from the experimental samples to create snapshots of how the two types of diamonds formed.

The pictures showed that the regular diamonds only form in the middle of Lonsdaleite veins under this new method.

“Seeing these little ‘rivers’ of Lonsdaleite and regular diamond for the first time was just amazing and really helps us understand how they might form,” Dougal McCulloch, the study’s lead author and a professor at the Royal Melbourne Institute of Technology, said. 

According to the scientists, Lonsdaleite has the potential to be used for cutting through ultra-solid materials on mining sites. As such, they said that creating more of this rare diamond is the long-term aim of their work.

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Siemens, Deutsche Bahn launch local hydrogen trains trial – The Guardian

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MUNICH (Reuters) – Siemens Mobility and Deutsche Bahn have started developing hydrogen-powered fuel cell trains and a filling station which will be trialled in 2024 with view to replace diesel engines on German local rail networks.

The prototype, to be built by Siemens, is based on electric railcar Mireo Plus which will be equipped with fuel cells to turn hydrogen and oxygen into electricity on board, and with a battery, both companies said.

Siemens mobility chief executive Michael Peter told Reuters the train combined the possibility to be fed by three sources in a modular system – either by the battery, the fuel cell or even existing overhead lines, depending on where it would run.

German railway operator Deutsche Bahn has not electrified 40% of its 33,000 kilometre (km) long network, on which it runs 1,300 fossil-fuel emitting diesel locomotives.

Rail transport must be decarbonised over the long-term under European Union and national climate targets.

“Our hydrogen trains are able to replace diesel-fuelled trains in the long term,” Peter said.

The new prototype will be fuelled within 15 minutes, have a range of 600 km and a top speed of 160 km/hour.

It will be tested between Tuebingen, Horb and Pforzheim in Baden Wuerttemberg state.

The main target market are operators of regional networks that typically re-order lots of 10 to 50 trains, Peter said.

“We see a market potential of 10,000-15,000 trains in Europe that will need to be replaced over the next 10-15 years, with 3,000 alone in Germany,” he said.

Each train will cost between five and 10 million euros ($5.9-$11.9 million), creating a market potential of 50-150 billion euros overall.

The Berlin government expects green hydrogen to become competitive with fossil fuels over the long term and to play a key role in decarbonising industry, heating and transport.

(Reporting by Joern Poltz in Munich and Vera Eckert in Frankfurt, editing by David Evans)

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