Connect with us

Science News

International Space Station Spacewalk, July 1, 2020 – NASA

Tune in for our next International Space Station spacewalk! On Wednesday, July 1, NASA astronauts Chris Cassidy and Robert Behnken will begin the 229th space…

Published

on

post featured image

Science News

Does UV light kill the new coronavirus? – Live Science

Published

on

post featured image

Ultraviolet light has been used to stop pathogens in their tracks for decades. But does it work against SARS-CoV-2, the virus behind the pandemic?
The short answer is yes. But it takes the right kind of UV in the right dosage, a complex operation that is best administered by trained professionals. In other words, many at-home UV-light devices claiming to kill SARS-CoV-2 likely aren’t a safe bet. 
UV radiation can be classified into three types based on wavelength: UVA, UVB and UVC. Nearly all the UV radiation that reaches Earth is UVA, because most of UVB and all of UVC light is absorbed by the ozone layer, according to the Centers for Disease Control and Prevention
. And it’s UVC, which has the shortest wavelength and the highest energy, that can act as a disinfectant. 
Related: What is ultraviolet light?
“UVC has been used for years, it’s not new,” Indermeet Kohli, a physicist who studies photomedicine in dermatology at Henry Ford Hospital in Detroit, told Live Science. UVC at a specific wavelength, 254 nanometers, has been successfully used to inactivate H1N1 influenza and other coronaviruses
, such as severe acute respiratory virus (SARS-CoV) and Middle Eastern Respiratory Syndrome (MERS-CoV), she said. A study published June 26 to the preprint database medRxiv
from Kohli’s colleagues awaiting peer review now confirms that UVC also eliminates SARS-CoV-2. 
UVC-254 works because this wavelength causes lesions in DNA and RNA. Enough exposure to UVC-254 damages the DNA
and RNA so that they can’t replicate, effectively killing or inactivating a microorganism or virus. 
“The data that backs up this technology, the ease of use, and the non-contact nature” of UVC make it a valuable tool amid the pandemic, Kohli said. But responsible, accurate use is critical. UVC’s DNA-damaging capabilities make it extremely dangerous to human skin and eyes, Kohli said. She cautioned that UVC disinfection technologies should primarily be left to medical facilities and evaluated for safety and efficacy by teams with expertise in photomedicine and photobiology. 
When it comes to a-home UVC lamps, their ability to damage skin and eyes isn’t the only danger, Dr. Jacob Scott, a research physician in the Department of Translational Hematology and Oncology Research at Cleveland Clinic, said. These devices also have low quality control, which means there’s no guarantee that you’re actually eliminating the pathogen, he said.  
“UVC does kill the virus, period, but the issue is you have to get enough dose,” Scott told Live Science. “Particularly, for N95 masks, which are porous, it takes a pretty big dose” of UVC-254 nm to eliminate SARS-CoV-2. This kind of accuracy isn’t possible with at-home devices. 
In hospitals, the geometry of the room, shadowing, timing and the type of material or object being disinfected are all accounted for when experts determine the right dosage of UVC needed to kill pathogens. But that kind of “quality assurance is really hard out in the world, out in the wild,” Scott said. At-home devices don’t offer that kind of precision, so using them could offer a false assurance that SARS-CoV-2 has been eliminated when it hasn’t, he noted. “Having something you think is clean, but it’s not, is worse than something that you know is dirty” because it affects your behavior toward that object, he said. 
Both Kohli and Scott and their teams are working to make UVC disinfection of personal protective equipment (PPE), such as face masks and N95 respirators, more efficient. Kohli’s group advises hospitals and vendors repurposing existing UVC equipment for N95 respirator decontamination. Scott’s group developed
a machine
that can be used by smaller medical facilities and a software program that helps users factor in the geometry of the disinfection room so that staff can deliver the most effective dose of UVC. 
There are ongoing conversations in the field about installing UVC units in ceilings to decontaminate circulating air, Kohli said. And others are researching another wavelength of UVC called UVC-222 or Far-UVC, which may not damage human cells, she added. But that will require more research, Kohli said.  Still, it’s clear that “used accurately and responsibly, UVC has enormous potential.”
Originally published on Live Science.

Click here to view the original article.

Continue Reading

Science News

Dark matter SHOCK: Scientist announces new Moon core theory – ‘Newton’s out-of-date’ – Express.co.uk

A SUCCESSOR to Sir Isaac Newton’s law of universal gravitation theory has been proposed by a UK-based scientist.

Published

on

post featured image

Click here to view the original article.

Continue Reading

Science News

Ring of Firepower: Electric Hall Thruster for NASA’s Psyche Spacecraft Propulsion – SciTechDaily

NASA’s Psyche spacecraft, set to launch in August 2022, will travel to its target in the main asteroid belt between Mars and Jupiter under the power of super-efficient electric propulsion. This photo captures an operating electric Hall thruster identical to t…

Published

on

post featured image

An electric Hall thruster, identical to those that will be used to propel NASA’s Psyche spacecraft, undergoes testing at NASA’s Jet Propulsion Laboratory. The blue glow is produced by the xenon propellant, a neutral gas used in car headlights and plasma TVs. Credit: NASA/JPL-Caltech
NASA’s Psyche spacecraft, set to launch in August 2022, will travel to its target in the main asteroid belt between Mars and Jupiter under the power of super-efficient electric propulsion. This photo captures an operating electric Hall thruster identical to those that will be used to propel the Psyche spacecraft. This photo was taken at NASA’s Jet Propulsion Laboratory in Southern California on May 20, 2020 with an iPhone, through the thick window of a vacuum chamber used to simulate the environment of deep space.
The thruster works by turning xenon gas, a neutral gas used in car headlights and plasma TVs, into xenon ions. As the xenon ions are accelerated out of the thruster, they create the thrust that will propel the spacecraft. The xenon plasma emits a blue glow, seen here, as it operates. An observer in space traveling behind Psyche would see the blue glow of plasma trailing behind the spacecraft. Solar arrays will provide the electricity that powers the thrusters. Hall thrusters will be used for the first time beyond lunar orbit, demonstrating that they could play a role in supporting future missions to deep space.
Arizona State University in Tempe leads the Psyche mission. JPL is responsible for the mission’s overall management, system engineering, integration and test, and mission operations. Maxar Technologies in Palo Alto, California, is providing the high-power solar electric propulsion spacecraft chassis.

Click here to view the original article.

Continue Reading

Trending