Sunday, December 18, 2022

ESPRESSO and CARMENES discover two potentially habitable exo-Earths around a star near the Sun

INSTITUTO DE ASTROFÍSICA DE CANARIAS (IAC)

Two Earth-mass planets orbiting the star GJ 1002 — IMAGE: ARTIST'S IMPRESSION OF TWO EARTH-MASS PLANETS ORBITING THE STAR GJ 1002 view more
CREDIT: ALEJANDRO SUÁREZ MASCAREÑO AND INÉS BONET (IAC)

“Nature seems bent on showing us that Earth-like planets are very common. With these two we now know 7 in planetary systems quite near to the Sun” explains Alejandro Suárez Mascareño, an IAC researcher, who is the first author of the study accepted for publication in Astronomy & Astrophysics.

The newly discovered planets orbit the star GJ 1002, which is at a distance of less than 16 light years from the Solar System. Both of them have masses similar to that of the Earth, and they are in the habitability zone of their star. GJ 1002b, the inner of the two, takes little more than 10 days to complete an orbit around the star, while GJ 1002c needs a little over 21 days. “GJ 1002 is a red dwarf star, with barely one eighth the mass of the Sun. It is quite a cool, faint star. This means that its habitability zone is very close to the star” explains Vera María Passegger, a co-author of the article and an IAC researcher.

The proximity of the star to our Solar System implies that the two planets, especially GJ 1002c, are excellent candidates for the characterization of their atmospheres based either on their reflected light, or on their thermal emission. “The future ANDES spectrograph for the ELT telescope at ESO in which the IAC is participating, could study the presence of oxygen in the atmosphere of GJ 1002c” notes Jonay I. González Hernández, an IAC researcher who is a co-author of the article. In addition, both planets satisfy the characteristics needed for them to be objectives for the future LIFE mission, which is presently in a study phase.

The discovery was made during a collaboration between the consortia of the two instruments ESPRESSO and CARMENES. GJ 1002 was observed by CARMENES between 2017 and 2019, and by ESPRESSO between 2019 and 2021. “Because of its low temperature the visible light from GJ 1002 is too faint to measure its variations in velocity with the majority of spectrographs” says says Ignasi Ribas, researcher at the Institute of Space Sciences (ICE-CSIC) and director of the Institut d'Estudis Espacials de Catalunya (IEEC). CARMENES has a sensitivity over a wide range of near infrared wavelengths which is superior to those of other spectrographs aimed at detecting variations in the velocities of stars, and this allowed it to study GJ 1002, from the 3.5m telescope at Calar Alto observatory.

The combination of ESPRESSO, and the light gathering power of the VLT 8m telescopes at ESO allowed measurements to be made with an accuracy of only 30 cm/sec, not attainable with any other instrument in the world. “Either of the two groups would have had many difficulties if they had tackled this work independently. Jointly we have been able to get much further than we would have done acting independently” states Suárez Mascareño.

Infographic comparing the relative distance between the discovered planets and their star with the inner planets of the Solar System. The region marked in green represents the habitable zone of the two planetary systems.
CREDIT
Design: Alejandro Suárez Mascareño (IAC). Planets of the Solar System: NASA

JOURNAL

Astronomy and Astrophysics

DOI

10.1051/0004-6361/202244991

ARTICLE TITLE

Two temperate Earth-mass planets orbiting the nearby star GJ 1002

Webb Space Telescope reveals previously shrouded newborn stars

Webb’s infrared camera peers through dust clouds, enabling discovery

Peer-Reviewed Publication

RICE UNIVERSITY

JWST infrared image of Cosmic Cliffs — IMAGE: ASTRONOMERS FROM RICE UNIVERSITY AND OTHER ORGANIZATIONS DUG DEEP INTO THE DATA FROM THIS NEAR-INFRARED IMAGE, ONE OF THE FIRST TAKEN BY NASA’S JAMES WEBB SPACE TELESCOPE. THE IMAGE SHOWS A STAR-FORMING REGION IN THE CONSTELLATION CARINA KNOWN AS THE COSMIC CLIFFS. MANY NEWBORN STARS IN SUCH REGIONS ARE SHROUDED IN THICK CLOUDS OF DUST. WEBB’S INFRARED CAMERA PENETRATED THE DUST, ALLOWING ASTRONOMERS TO DISCOVER TELLTALE SIGNS OF TWO DOZEN INFANT STARS THAT HADN’T BEEN PREVIOUSLY DETECTED. view more
CREDIT: IMAGE COURTESY OF NASA, ESA, CSA AND STSCI

HOUSTON – (Dec. 16, 2022) – Rice University astronomer Megan Reiter and colleagues took a “deep dive” into one of the first images from NASA’s James Webb Space Telescope and were rewarded with the discovery of telltale signs from two dozen previously unseen young stars about 7,500 light years from Earth.

The published research in the December issue of the Monthly Notices of the Royal Astronomical Society offers a glimpse of what astronomers will find with Webb’s near-infrared camera. The instrument is designed to peer through clouds of interstellar dust that have previously blocked astronomers’ view of stellar nurseries, especially those that produce stars similar to Earth’s sun.

Reiter, an assistant professor of physics and astronomy, and co-authors from the California Institute of Technology, the University of Arizona, Queen Mary University in London and the United Kingdom’s Royal Observatory in Edinburgh, Scotland, analyzed a portion of Webb’s first images of the Cosmic Cliffs, a star-forming region in a cluster of stars known as NGC 3324.

“What Webb gives us is a snapshot in time to see just how much star formation is going on in what may be a more typical corner of the universe that we haven’t been able to see before,” said Reiter, who led the study.

Located in the southern constellation Carina, NGC 3324 hosts several well-known regions of star formation that astronomers have studied for decades. Many details from the region have been obscured by dust in images from the Hubble Space Telescope and other observatories. Webb’s infrared camera was built to see through dust in such regions and to detect jets of gas and dust that spew from the poles of very young stars.

Reiter and colleagues focused their attention on a portion of NGC 3324 where only a few young stars had previously been found. By analyzing a specific infrared wavelength, 4.7 microns, they discovered two dozen previously unknown outflows of molecular hydrogen from young stars. The outflows range in size, but many appear to come from protostars that will eventually become low-mass stars like Earth’s sun.

“The findings speak both to how good the telescope is and to how much there is going on in even quiet corners of the universe,” Reiter said.

Within their first 10,000 years, newborn stars gather material from the gas and dust around them. Most young stars eject a fraction of that material back into space via jets that stream out in opposite directions from their poles. Dust and gas pile up in front of the jets, which clear paths through nebular clouds like snowplows. One vital ingredient for baby stars, molecular hydrogen, gets swept up by these jets and is visible in Webb’s infrared images.

“Jets like these are signposts for the most exciting part of the star formation process,” said study co-author Nathan Smith of the University of Arizona. “We only see them during a brief window of time when the protostar is actively accreting.”

The accretion period of early star formation has been especially difficult for astronomers to study because it is fleeting — usually just a few thousand years in the earliest portion of a star’s multimillion-year childhood.

Study co-author Jon Morse of the California Institute of Technology said jets like those discovered in the study “are only visible when you embark on that deep dive — dissecting data from each of the different filters and analyzing each area alone.

“It’s like finding buried treasure,” Morse said.

Reiter said the size of the Webb telescope also played a role in the discovery.

“It's just a huge light bucket,” Reiter said. “That lets us see smaller things that we might have missed with a smaller telescope. And it also gives us really good angular resolution. So we get a level of sharpness that allows us to see relatively small features, even in faraway regions.”

The Webb Space Telescope program is led by NASA in partnership with the European Space Agency (ESA) and the Canadian Space Agency (CSA). The telescope’s science and mission operations are led by the Space Telescope Science Institute (STScI) in Baltimore.

The research was supported by NASA (NAS 5-0312, NAS 5–26555), STScI and a Dorothy Hodgkin Fellowship from the UK’s Royal Society.

-30-

Matter flows away from the poles of newborn stars in fast-moving columns that plow through nebular clouds. Gas and dust pile up in front of these outflows, forming waves called “bow shocks” in much the same way that bow waves form at the leading edge of seagoing ships. This false-color infrared image from the James Webb Space Telescope shows bow shocks of molecular hydrogen (red) streaming away from newborn stars in a star-forming region called the Cosmic Cliffs in the southern constellation Carina.

CREDIT

Image courtesy of NASA, ESA, CSA and STScI

Peer-reviewed paper:

“Deep diving off the ‘Cosmic Cliffs’: previously hidden outflows in NGC 3324 revealed by JWST” | Monthly Notices of the Royal Astronomical Society | DOI: 10.1093/mnras/stac2820

Megan Reiter, Jon A. Morse, Nathan Smith, Thomas J. Haworth, Michael A. Kuhn and Pamela D. Klaassen

https://doi.org/10.1093/mnras/stac2820

High-resolution IMAGES are available for download at:

https://news-network.rice.edu/news/files/2022/12/1215_COSMIC-f2a-lg.jpg
CAPTION: Astronomers from Rice University and other organizations dug deep into the data from this near-infrared image, one of the first taken by NASA’s James Webb Space Telescope. The image shows a star-forming region in the constellation Carina known as the Cosmic Cliffs. Many newborn stars in such regions are shrouded in thick clouds of dust. Webb’s infrared camera penetrated the dust, allowing astronomers to discover telltale signs of two dozen infant stars that hadn’t been previously detected. (Image courtesy of NASA, ESA, CSA and STScI)

https://news-network.rice.edu/news/files/2022/12/1215_COSMIC-mr9Fit-lg.jpg
CAPTION: Rice University astronomer Megan Reiter led a “deep dive” study of the earliest images from the James Webb Space Telescope. The research revealed telltale signs of two dozen previously uncataloged young stars in the star cluster NGC 3324 in the constellation Carina. (Photo by Jeff Fitlow/Rice University)

https://news-network.rice.edu/news/files/2022/12/1215_COSMIC-f2b-lg.jpg
CAPTION: Matter flows away from the poles of newborn stars in fast-moving columns that plow through nebular clouds. Gas and dust pile up in front of these outflows, forming waves called “bow shocks” in much the same way that bow waves form at the leading edge of seagoing ships. This false-color infrared image from the James Webb Space Telescope shows bow shocks of molecular hydrogen (red) streaming away from newborn stars in a star-forming region called the Cosmic Cliffs in the southern constellation Carina. (Image courtesy of NASA, ESA, CSA and STScI)

JOURNAL

Monthly Notices of the Royal Astronomical Society

DOI

10.1093/mnras/stac2820

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Deep diving off the ‘Cosmic Cliffs’: previously hidden outflows in NGC 3324 revealed by JWST

JWST PEARLS project unveils exquisite views of distant galaxies

Peer-Reviewed Publication

ARIZONA STATE UNIVERSITY

The press release and accompanying multimedia are available online on ASU News here

For decades, the Hubble Space Telescope and ground-based telescopes have provided us with spectacular images of galaxies. This all changed when the James Webb Space Telescope (JWST) launched in December 2021 and successfully completed commissioning during the first half of 2022. For astronomers, the universe, as we had seen it, is now revealed in a new way never imagined by the telescope's Near-Infrared Camera(NIRCam) instrument.

The NIRCam is Webb's primary imager that covers the infrared wavelength range from 0.6 to 5 microns. NIRCam detects light from the earliest stars and galaxies in the process of formation, the population of stars in nearby galaxies, as well as young stars in the Milky Way and Kuiper Belt objects.

The Prime Extragalactic Areas for Reionization and Lensing Science, or PEARLS, project is the subject of a recent study published in Astronomical Journal by a team of researchers, including Arizona State University School of Earth and Space Exploration Regents Professor Rogier Windhorst, Research Scientist Rolf Jansen, Associate Research Scientist Seth Cohen, Research Assistant Jake Summers and Graduate Associate Rosalia O'Brien, along with the contribution of many other researchers.

For researchers, the PEARLS program's images of the earliest galaxies show the amount of gravitational lensing of objects in the background of massive clusters of galaxies, allowing the team to see some of these very distant objects. In one of these relatively deep fields, the team has worked with stunning multicolor images to identify interacting galaxies with active nuclei.

Windhorst and his team's data show evidence for giant black holes in their center where you can see the accretion disc — the stuff falling into the black hole, shining very brightly in the galaxy center. Plus, lots of galactic stars show up like drops on your car's windshields — like you're driving through intergalactic space. This colorful field is straight up from the ecliptic plane, the plane in which the Earth and the moon, and all the other planets, orbit around the sun.

"For over two decades, I've worked with a large international team of scientists to prepare our Webb science program," Windhorst said. "Webb's images are truly phenomenal, really beyond my wildest dreams. They allow us to measure the number density of galaxies shining to very faint infrared limits and the total amount of light they produce. This light is much dimmer than the very dark infrared sky measured between those galaxies."

The first thing the team can see in these new images is that many galaxies that were next to or truly invisible to Hubble are bright in the images taken by Webb. These galaxies are so far away that the light emitted by stars has been stretched.

The team focused on the North Ecliptic Pole time domain field with the Webb telescope — easily viewed due to its location in the sky. Windhorst and the team plan to observe it four times.

The first observations, consisting of two overlapping tiles, produced an image that shows objects as faint as the brightness of 10 fireflies at the distance of the moon (with the moon not there). The ultimate limit for Webb is one or two fireflies. The faintest reddest objects visible in the image are distant galaxies that go back to the first few hundred million years after the Big Bang.

For most of Jansen's career, he's worked with cameras on the ground and in space, where you have a single instrument with a single camera that produces one image. Now scientists have an instrument that has not just one detector or one image coming out of it, but 10 simultaneously. For every exposure NIRCam takes, it gives 10 of these images. That's a massive amount of data, and the sheer volume can be overwhelming.

To process that data and channel it through the analysis software of collaborators around the globe, Summers has been instrumental.

“The JWST images far exceed what we expected from my simulations prior to the first science observations,” Summers said. “Analyzing these JWST images, I was most surprised by their exquisite resolution.”

Jansen’s primary interest is to figure out how galaxies like our own Milky Way came to be. And the way to do that is by looking far back in time at how galaxies came together, seeing how they evolved, effectively, and so tracing the path from the Big Bang to people like us.

"I was blown away by the first PEARLS images," Jansen said. "Little did I know, when I selected this field near the North Ecliptic Pole, that it would yield such a treasure trove of distant galaxies, and that we would get direct clues about the processes by which galaxies assemble and grow — I can see streams, tails, shells and halos of stars in their outskirts, the leftovers of their building blocks."

Third-year astrophysics graduate student O'Brien designed algorithms to measure faint light between the galaxies and stars that first catch our eye.

"The diffuse light that I measured in between stars and galaxies has cosmological significance, encoding the history of the universe," O'Brien said. "I feel fortunate to start my career right now — JWST data is like nothing we have ever seen, and I'm excited about the opportunities and challenges it offers."

“I expect that this field will be monitored throughout the JWST mission, to reveal objects that move, vary in brightness or briefly flare up, like distant exploding supernovae or accreting gas around black holes in active galaxies,” Jansen said.

ASU press contact:  

Kim Baptista, 707-479-0311, Kim.baptista@asu.edu

###

JOURNAL

The Astronomical Journal

DOI

10.3847/1538-3881/aca163

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

JWST PEARLS. Prime Extragalactic Areas for Reionization and Lensing Science: Project Overview and First Results

ARTICLE PUBLICATION DATE

14-Dec-2022

New study confirms the light from

outside our galaxy brighter than

expected

Study led by RIT scientists uses data taken by LORRI on NASA’s New Horizons mission

Peer-Reviewed Publication

ROCHESTER INSTITUTE OF TECHNOLOGY

Scientists analyzed new measurements showing that the light emitted by stars outside our galaxy is two to three times brighter than the light from known populations of galaxies, challenging assumptions about the number and environment of stars are in the universe. Results of the study led by researchers at Rochester Institute of Technology have been posted to ArXiv and accepted for publication in The Astrophysical Journal.

The research team analyzed hundreds of images of background light taken by the Long-Range Reconnaissance Imager (LORRI) on NASA’s New Horizons mission to calculate the cosmic optical background (COB)—the sum of light emitted by stars beyond the Milky Way over the history of the universe. If the COB brightness doesn’t equal the light from galaxies we know about, it suggests there might be missing sources of optical light in the universe.

“We see more light than we should see based on the populations of galaxies that we understand to exist and how much light we estimate they should produce,” said Teresa Symons ’22 Ph.D. (astrophysical sciences and technology), who led the study for her dissertation and is now a postdoctoral researcher at University of California Irvine. “Determining what is producing that light could change our fundamental understanding of how the universe formed over time.”

Earlier this year, an independent team of scientists reported the COB was twice as large as originally believed in Astrophysical Journal Letters. Those results were no fluke, as corroborated using a much broader set of LORRI observations in the new study by Symons, RIT Associate Professor Michael Zemcov, and researchers at the Jet Propulsion Laboratory at Caltech, UC Irvine, UC Berkeley, and Johns Hopkins University.

While an unobscured measurement of the COB is difficult to achieve from the Earth due to dust between planets, the New Horizons spacecraft is at the edge of our solar system where this foreground is minimal and provides a much clearer view for this type of study. The scientists hope that future missions and instruments can be developed to help explore the discrepancy.

“This has gotten to the point where it’s an actual mystery that needs to be solved,” said Zemcov, a research professor at RIT’s Center for Detectors and School of Physics and Astronomy. “I hope that some of the experiments we’re involved in here at RIT including CIBER-2 and SPHEREx can help us resolve the discrepancy.”

To learn more, read the full study on the ArXiv website.

JOURNAL

The Astrophysical Journal

ARTICLE TITLE

A Measurement of the Cosmic Optical Background and Diffuse Galactic Light Scaling from the R < 50 AU New Horizons-LORRI Data

Astronomers discover clues about stellar ‘glitching’

New evidence shows that many stars experience irregularities in their core

Peer-Reviewed Publication

OHIO STATE UNIVERSITY

COLUMBUS, Ohio – Astronomers have found a way to peer into the physics of some of the brightest stars in the sky.

Using data from NASA’s Kepler space telescope, an international team of researchers has found new evidence that red giants, dying stars that have exhausted their supply of hydrogen and are in the final stages of stellar evolution, often experience large-scale structural variations, or what are known as “glitches” deep inside their inner core.

The stellar glitches popularized in the media have to do with a star’s rotation, but lead author Mathieu Vrard studies a different kind of defect. The glitches in this study can affect a star’s oscillations, or the frequencies and paths that sound waves travel when passing through a star.

Red clump stars, helium-core burning objects, are often used in astrophysical studies as probes of distance to measure aspects like galaxy density, and to learn more about the physical processes behind stellar chemical evolution. So it’s vital that scientists understand why these discontinuities happen, said Vrard, a postdoctoral research associate in astronomy at the Ohio State University.

“By analyzing these variations, we can use them to obtain not only the global parameters of the star, but also information on the precise structure of those objects,” he said.

The study, recently published in the journal Nature Communications is the first to perform detailed observational characterizations on the deepest layers of these red giants.

In order to determine if these glitches were becoming more prevalent across certain star groups, the team selected a sample of 359 red giants that were below a certain stellar mass, and measured various properties and individual frequencies of each star.

The team found proof that 24 of the red giants surveyed (about 7% of those in the sample) had experienced intermittent structural discontinuities at one point or another during their lifetime. While 7% may not seem like much, if applied to all of the known stars in our universe, the number of stars that have these irregularities would be enormous.

There are two main theories that explain how these disturbances might work. The first scenario posits that glitches are present throughout the star’s evolution, but are generally very weak and below the threshold for what astronomers would categorize as a true discontinuity.

The second suggests that irregularities are “smoothed out” by some unknown physical process that later leads to changes in the structure of the star’s core.

As it turns out, the first scenario is not supported by this study’s model, which predicts that glitches observed are actually a common occurrence, but more precise data is needed before scientists can confidently subscribe to the second.

“What we think is that the second theory might hold up better because the first one didn't make sense with our observations,” Vrard said.

As the study offers a better characterization of the physical processes taking place inside red-giant stars, Vrard’s work could potentially have large implications for the field of asteroseismology – a branch of astronomy that studies the internal composition of stars using the oscillations of sound waves – and for galactic archaeology, a field that uses detailed stellar fossil records to uncover the history of the universe.

And though Vrard’s current analysis has come to an end, he aims to build on the scientific community’s knowledge of red-giant stars by examining more precise data that could help cultivate even more refined stellar models.

This work received support from NASA as well as the European Regional Development Fund.

Contact: Mathieu Vrard, Vrard.1@osu.edu

Written by: Tatyana Woodall, Woodall.52@osu.edu

JOURNAL

Nature Communications

DOI

10.1038/s41467-022-34986-z

METHOD OF RESEARCH

Meta-analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Evidence of structural discontinuities in the inner core of red-giant stars

ARTICLE PUBLICATION DATE

16-Dec-2022

Astronomers may have uncovered

how galaxies change their shape

Researchers may have answered a decades-old question about galaxy evolution, leveraging the power of artificial intelligence (AI) to accelerate their research.

Peer-Reviewed Publication

INTERNATIONAL CENTRE FOR RADIO ASTRONOMY RESEARCH

The Eagles simulation classify galaxy types using AI — IMAGE: A REPRESENTATION OF HOW THE EAGLES PROGRAM CLASSIFIES GALAXY AS ASSESSED BY AI. view more
CREDIT: CREDIT: ICRAR

Researchers may have answered a decades-old question about galaxy evolution, leveraging the power of artificial intelligence (AI) to accelerate their research.

Ever since the Hubble Sequence, that classifies galaxy morphologies, was invented in 1926, astronomers have been refining our understanding of galaxy evolution and morphology as our technology advances.

By the 1970’s, researchers had confirmed that lone galaxies tend to be spiral-shaped, and those found in clusters of galaxies were likely to be smooth and featureless, known as elliptical and lenticular (shaped like a lens).

Published today in the journal Monthly Notices of the Royal Astronomical Society, new research led by astronomers at the International Centre for Radio Astronomy Research (ICRAR) may have uncovered the reason for these differences in shapes.

Lead author Dr Joel Pfeffer from The University of Western Australia node of ICRAR, said the research explains the ‘morphology-density relation’ – where clustered galaxies appear smoother and more featureless than their solo counterparts.

“We’ve discovered there are a few different things going on when we get lots of galaxies packed together,” Dr Pfeffer said.

“The spiral arms on galaxies are so fragile, and as you go to higher densities in the galaxy clusters, spiral galaxies start to lose their gas.

“This loss of gas causes them to ‘drop’ their spiral arms, transforming into a lenticular shape.”

“Another cause is galaxy mergers, which can see two or more spiral galaxies crashing together to form one large elliptical galaxy in the aftermath.”

The study utilised the powerful EAGLE simulations to analyse a group of galaxies in detail, using an AI algorithm to classify galaxies by their shape.

The neural network-based algorithm was trained by ICRAR PhD candidate Mitchell Cavanagh and can classify almost 20,000 galaxies per minute, compressing what would typically take weeks into one hour.

The simulations closely match what has been observed in the Universe, giving researchers the confidence to use the simulation results to interpret observations of galaxy clusters

The study also identified several lenticular galaxies outside of the high-density regions where they are expected, with the modelling suggesting they were created by the merging of two galaxies.

Dr Pfeffer said the work brings together various pieces of research in galactic evolution, to understand the morphology-density relation for the first time.

“There's been lots of suggestions over time,” he said. “But this is the first work to really put all of pieces of the puzzle together.”

PUBLICATION:

https://academic.oup.com/mnras/article/518/4/5260/6891783
‘The galaxy morphology-density relation in the EAGLE simulation, published in Monthly Notices of the Royal Astronomical Society on December 16, 2022.’

MORE INFO:

ICRAR
The International Centre for Radio Astronomy Research (ICRAR) is a joint venture between Curtin University and The University of Western Australia with support and funding from the State Government of Western Australia.

The EAGLE simulation
EAGLE (Evolution and Assembly of GaLaxies and their Environments) is a simulation aimed at understanding how galaxies form and evolve. This simulation is one of the largest cosmological hydrodynamical simulations ever, using nearly 7 billion particles to model the physics. It took more than one and a half months of computer time on 4000 compute cores of the DiRAC-2 supercomputer in Durham.

MULTIMEDIA:
Images are available from www.icrar.org/eagle-morphology-density

JOURNAL

Monthly Notices of the Royal Astronomical Society

DOI

10.1093/mnras/stac3466

METHOD OF RESEARCH

Computational simulation/modeling

ARTICLE TITLE

The galaxy morphology-density relation in the EAGLE simulation

ARTICLE PUBLICATION DATE

16-Dec-2022

Economic behaviour not influenced by gender or biological sex, study finds

Gender and sex assigned at birth are not as decisive in economic decision-making as previously thought

Peer-Reviewed Publication

UNIVERSITY OF EXETER

Gender and sex assigned at birth are not as decisive in economic decision-making as previously thought, a new study finds.

A new study published in Scientific Reports is the first analysis of transgender and cisgender economic behaviour, and the first to consider whether sex assigned at birth plays a significant part in economic decisions.

Helena Fornwagner and Brit Grosskopf from the University of Exeter Business School and Alexander Lauf, Vanessa Schöller, and Silvio Städter (University of Regensburg) have for the first time investigated the role of gender identity and biological sex in economic decision-making.

The researchers explored whether being transgender or cisgender impacted factors that could influence whether we compete with others in applying for a new job, investing in a risky asset or donating to charity.

In a controlled experimental study featuring 780 participants, with around half identifying as transgender, they hypothesised that if gender identity does determine levels of competitiveness, risk-taking or altruism with money, then those with the same gender identity (cis men and trans men, and cis women and trans women) will make similar decisions. Those with a different gender identity would make significantly different economic decisions. Moreover, it was suggested that participants having the same biological sex (cismen and transwomen, and ciswomen and transmen) would behave comparably.

The researchers used a series of well-known economic experiments to determine how competitive the participants were with money, their willingness to take risks and how willing they were to give to charity. Before making any decisions, the participants completed a word search priming exercise that subconsciously assigned them a masculine, feminine or gender-neutral identity by asking them to find gender-specific words.

Using their study design, the researchers first test for a correlation impact of gender and sex by comparing the behaviour of cis-gender men, cis women, trans men and trans women. Second, the priming intervention enabled to control for causal inferences about gender and behaviour.

But in contrast to previous studies that have established links between gender and economic behaviour, the researchers found that gender and biological sex actually make no significant difference to our economic decisions.

Part of their rationale for this unexpected finding is that educational initiatives and a greater awareness of gender equality in private and professional settings have narrowed any economic behavioural differences, which were first established in studies almost two decades ago.

Dr Fornwagner said: “Gender has long been reported to be a driving factor in domains such as competitiveness, risk-taking and altruism, but our study is the first to ask how much can be associated with gender, and how much is based on the biological sex people are endowed with.

“Despite the partly unexpected findings that led us to conclude that the role of gender and sex is not as decisive for economic behaviour as previously assumed, we believe there are several important take-aways from this study.“

“Transgender individuals have become a more and more visible part of society. Thus, we think it is crucial to understand their economic behaviour and essential to expand experimental economic research to all groups summarised under the LGBTQ+ flag to acknowledge the colourful society we are already part of also in our scientific research.”

“On the robustness of gender differences in economic behavior” is published in Scientific Reports.

JOURNAL

Scientific Reports

DOI

10.1038/s41598-022-25141-1

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

On the robustness of gender differences in economic behavior

ARTICLE PUBLICATION DATE

15-Dec-2022

Once a terrorist, always a terrorist?

Study examines the UN’s terrorist list

Peer-Reviewed Publication

MARTIN-LUTHER-UNIVERSITÄT HALLE-WI

At the United Nations, an ombudsperson reviews who is on the list of terrorists from Al Qaeda and the Islamic State. If someone feels that they have been wrongly placed on the list and should be removed, they can request that their case should be reviewed. Since the establishment of the office in 2010, 63 people have been struck off the list on the basis of recommendations made by the ombudsperson. Those on the list are subjected to far-reaching sanctions, for example travel bans and the freezing of bank accounts. Dr Andrej Lang, a legal scholar from Martin Luther University Halle-Wittenberg (MLU), takes stock of this issue in the American Journal of International Law.

The Office of the Ombudsperson for the United Nations’ "1267 Sanctions Regime" was introduced in 2010 - under pressure from the European Court of Justice. The regime was established by the UN Security Council in 1999 to combat terrorism by the Taliban and Al-Qaeda. Its aim was to target members and supporters of terrorist organisations. The Taliban were later removed from the regime and the so-called Islamic State (ISIL) was added. "International law has long permitted the Security Council to take economic sanctions against individual countries in order to maintain or restore international peace and security. However, these measures always affect an entire nation and its population. The sanctions regime was designed to allow taking targeted actions against individuals," explains legal scholar Dr Andrej Lang from MLU. The Security Council can decide whether individuals should be subjected to far-reaching sanctions. "When a person is placed on this list, all United Nations Member States are obliged to freeze that person’s accounts and restrict their freedom of movement by banning them from leaving the country," Lang adds. The measures aim to curb the financing of terrorism and thus prevent terrorist attacks.

However, according to Lang, the process for putting people on this list is problematic. The decisions are made by a UN Security Council committee that is staffed by diplomats. Sometimes a Member State will allude to confidential documents created by their secret service without submitting these to the other Member States. Even more problematic is that not everyone who is sanctioned has been notified directly that their name is on the list. "There have been cases where a person suddenly could no longer pay his rent because his account had been frozen. That can derail his entire life," explains Lang. For his new study, the scholar examined the importance of the office of the ombudsperson and its work. It is an institution that persons can turn to if they believe they have been wrongly placed on the list. In addition to conducting an extensive review of the literature and publicly available UN documents, Lang also performed numerous interviews with diplomats, lawyers representing people on the list, and the three former ombudspersons. He used this material to produce the most comprehensive assessment of the ombudsperson’s role to date and placed its work within the current legal discourse on international dispute settlement and security politics.

When a person on the list approaches the ombudsperson, she will start an investigation. At the end of these proceedings, the ombudsperson recommends whether the person should remain on or be removed from the list. This recommendation can be overruled only if all 15 members of the Sanctions Committee vote against it, or if the case is referred to the Security Council - neither of which has happened yet. "This gives the ombudsperson a strong recommendation power," says Lang. Around 450 people have been placed on the terrorist list since it was first introduced, and 105 of these people have initiated proceedings with the ombudsperson. According to Lang, most of these cases have been resolved. In most instances, a recommendation is made to remove the person from the list and the UN member states have so far always complied with this recommendation except in one case. "This is surprising since, in many cases, a number of states are convinced that the people deserved to remain on the list," says Lang. The researcher notes that the sheer amount of people removed from the list does not necessarily point to a serious flaw in the sanctions regime: "In the first few years, some people were wrongly placed on the terrorist list. However, if you look at the list now, for most people it seems justifiable that they were originally put on the list because they were or are active for al-Qaida or the ISIL." However, after a certain amount of time, this status has to be scrutinised. This applies, for example, to people who were convicted by a national court and have served their prison sentences - but remain on the list.

Lang believes the work of the ombudsperson embodies a new trend in international law. "In the coming decades, it is likely that fewer international courts will be established than in the era following the Cold War. While the West’s influence wains, states like China and India are gaining in geopolitical influence, yet these states are not keen on creating such institutions. Under these conditions of a changing world order, dispute settlement bodies such as an ombudsperson constitute a compromise that may provide a better solution than it would initially appear - even if they do not always meet our Western standards for the rule of law," concludes Lang.

Study: Lang A. Alternatives to adjudication in international law. A case study of the ombudsperson to the ISIL and Al-Qaida sanctions regime of the UN security council. American Journal of International Law (2022). doi: 10.1017/ajil.2022.81

JOURNAL

American Journal of International Law

DOI

10.1017/ajil.2022.81

METHOD OF RESEARCH

Case study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Alternatives to adjudication in international law. A case study of the ombudsperson to the ISIL and Al-Qaida sanctions regime of the UN security council

Measuring times in billionths of a billionth of a second

Peer-Reviewed Publication

ULTRAFAST SCIENCE

Schematics of the experimental setup for Gouy phase interferometer. — IMAGE: SCHEMATICS OF THE EXPERIMENTAL SETUP FOR GOUY PHASE INTERFEROMETER. THE SCHEMATIC OF THE EXPERIMENTAL SETUP IS SHOWN IN FIGURE 1. THERE ARE TWO MOVEABLE MOLECULAR JETS SEPARATED IN SPACE NEAR THE FOCUS OF THE DRIVING INFRARED LASER BEAM. THE PHASE DIFFERENCE BETWEEN HHG EMISSIONS FROM THE TWO JETS INCLUDES A CONTRIBUTION FROM THE GOUEY PHASE (THE ONLY CONTRIBUTION WHEN THE SAME GAS IS FLOWING IN BOTH JETS) AND AN ADDITIONAL PHASE SHIFT DUE TO THE DIFFERENT INTRINSIC HHG PHASES OF DIFFERENT SPECIES. TO EXTRACT THAT INTRINSIC PHASE SHIFT, THE HHG SPECTRA ARE MEASURED FIRST WITH THE SAME GASES IN BOTH JETS AND THEN WITH DIFFERENT GASES SWITCHED BETWEEN THE JETS. THIS PROCEDURE ALLOWS TO COMPLETELY REMOVE THE CONTRIBUTION OF THE GOUY PHASE AND THE EFFECT OF SLIGHTLY DIFFERENT INTENSITIES AT THE JETS’LOCATIONS. view more
CREDIT: ULTRAFAST SCIENCE

How fast do electrons inside a molecule move? Well, it is so fast that it takes them just few attoseconds (1 as = 10-18 s or one billionth of billionth of a second) to jump from one atom to another. Blink and you missed it – millions of billions of times. So measuring such ultrafast processes is a daunting task.

Scientists at the Australian Attosecond Science Facility and the Centre for Quantum Dynamics of Griffith University in Brisbane Australia, led by Professor Robert Sang and Professor Igor Litvinyuk have developed a novel interferometric technique capable of measuring time delays with zeptosecond (a trillionth of a billionth of a second) resolution.

They have used this technique to measure the time delay between extreme ultraviolet light pulses emitted by two different isotopes of hydrogen molecules – H2 and D2 – interacting with intense infrared laser pulses.

This delay was found to be less than three attoseconds (one quintillionth of a second long) and is caused by slightly different motions of the lighter and heavier nuclei.

This study has been published in Ultrafast Science, a new Science Partner Journal.

The first author Dr Mumta Hena Mustary explains: “Such unprecedented time resolution is achieved via an interferometric measurement – overlapping the delayed light waves and measuring their combined brightness.”

The light waves themselves were generated by molecules exposed to intense laser pulses in the process called high harmonic generation (HHG).

HHG occurs when an electron is removed from a molecule by a strong laser field, is accelerated by the same field and then recombines with the ion giving up the energy in the form of extreme ultraviolet (XUV) radiation. Both intensity and phase of that XUV HHG radiation are sensitive to exact dynamics of the electron wavefunctions involved in this process – all different atoms and molecules emit HHG radiation differently.

While it is relatively straightforward to measure spectral intensity of HHG – a simple grating spectrometer can do that – measuring HHG phase is a far more difficult task. And the phase contains the most relevant information about the timing of various steps in the emission process.

To measure this phase, it is usual to perform a so-called interferometric measurement when two replicas of the wave with finely controlled delay are made to overlap (or interfere) with each other. They can interfere constructively or destructively depending on the delay and relative phase difference between them.

Such measurement is performed by a device called an interferometer. It is very difficult to build an interferometer for XUV light, in particular to produce and maintain a stable, known and finely tuneable delay between two XUV pulses.

The Griffith researchers solved this problem by taking advantage of the phenomenon known as the Gouy phase – when phase of a light wave is shifted a certain way while going through a focus.

For their experiments the researchers used two different isotopes of molecular hydrogen – the simplest molecule in nature. The isotopes – light (H2) and heavy (D2) hydrogen – differ only in mass of nuclei – protons in H2 and deuterons in D2. Everything else including the electronic structure and energies are identical.

Due to their larger mass the nuclei in D2 move slightly slower then those in H2. Because nuclear and electronic motions in molecules are coupled, nuclear motion affects the dynamics of the electron wavefunctions during the HHG process resulting in a small phase shift ΔφH2-D2 between the two isotopes.

This phase shift is equivalent to a time delay Δt = ΔφH2-D2 /ω where ω is the frequency of the XUV wave. The Griffith scientists measured this emission time delay for all the harmonics observed in the HHG spectrum – it was nearly constant and slightly below 3 attoseconds.

To understand their result the Griffith researchers were supported by theorists at Shanghai Jiao Tong University in Shanghai, China, led by Professor Feng He.

The SJTU scientists used the most advanced theoretical methods to comprehensively model the HHG process in the two isotopes of molecular hydrogen including all degrees of freedom for nuclear and electronic motion at various levels of approximation.

Their simulation reproduced experimental results well, and this agreement between theory and experiment gave the team confidence that the model captured the most essential features of the underlying physical process, so adjusting the model’s parameters and levels of approximation can determine the relative importance of various effects.

While the actual dynamics is quite complex, it was found that two-centre interference during the electron recombination step is the dominant effect.
“Because hydrogen is the simplest molecule in nature and it can be modelled theoretically with high accuracy it was used in these proof-of-principle experiments for benchmarking and validation of the method,” Professor Litvinyuk said.

“In the future, this technique can be used to measure ultrafast dynamics of various light-induced processes in atoms and molecules with unprecedented time resolution.”

JOURNAL

Ultrafast Science

DOI

10.34133/2022/9834102

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Attosecond Delays of High-Harmonic Emissions from Hydrogen Isotopes Measured by XUV Interferometer

Securing stable green energy under future extreme weather conditions

Climate is changing, and this will affect future energy systems based on solar and wind. But how? A new research project at Aarhus University will focus on this with a Sapere Aude grant from Independent Research Fund Denmark.

Grant and Award Announcement

AARHUS UNIVERSITY

Associate Professor Marta Victoria — IMAGE: ASSOCIATE PROFESSOR MARTA VICTORIA view more
CREDIT: CLAUS LILLEVANG, INDEPENDENT RESEARCH FUND DENMARK

In February 2021, the state of Texas was hit by wave of cold weather lasting two weeks. The event was without precedent, and the Texan energy supply, which is primarily dependent on wind, coal and gas, was completely unprepared for this kind of extreme weather.

Due to the cold weather, gas pipes and some wind turbines froze, and since this was accompanied by a period with low wind speeds, it caused two-week-long power outages in 4.5 million homes. The incident cost USD 24 billion and 262 people lost their lives. It was the worst winter-weather disaster ever in the US.

The European energy network is better interconnected and prepared to deal with such events, but in a future with increasing climate change and more extreme weather, such events will very likely occur again.

So how do we ensure a stable future energy system, if this will be based on energy sources that may well be sustainable and renewable, but that are also dependent on local weather conditions?

A new research project at Aarhus University will now try to explain.

"We can't build an energy system that takes account of everything. That would be extremely costly. So, what do we do if there is a long period without wind and without sun, and with a high demand for energy, and how can we adapt the system without over-dimensioning it? We need to find out what we have to be prepared for when the weather changes as a result of climate change," says Associate Professor Marta Victoria from the Department of Mechanical and Production Engineering at Aarhus University, who is heading the project.

She has just received a prestigious Sapere Aude-grant from Independent Research Fund Denmark (DFF) of DKK 6.2 million. Her project is called EXTREMES (Highly renewable energy systems under extreme weather events) and it aims to describe periods of extreme weather using statistics, and to design strategies to ensure that an energy system with a very high proportion of solar and wind energy is reliable, even under extreme weather conditions.

"How long will the worst period of low wind or solar production be? How many times a year will this happen? What is the worst period we can expect within a decade? Or a century? And what conditions should we adapt the system to? As a rule, there’s a backup, but in the project we’ll try to take into account situations where several adverse events happen at the same time, and where spatial and temporal fluctuations can be hard to predict," she says.

The project starts in spring 2023 and will run for four years.

Sapere Aude grants are awarded by Independent Research Fund Denmark to talented early-career researchers to enable them to develop and strengthen their own research ideas and establish themselves as research directors with the foundation's financial assistance.

This year, Independent Research Fund Denmark has awarded Sapere Aude grants to 41 researchers following 356 applications. Of these, 12 recipients are from Aarhus University: The 41 researchers share a total of DKK 247 million.

Plastic pollution kills sea urchin larvae

Peer-Reviewed Publication

UNIVERSITY OF EXETER

Sea urchin development — IMAGE: SEA URCHIN DEVELOPMENT IN UNCONTAMINATED SEAWATER AND VARIOUS CONCENTRATIONS OF PVC NURDLES view more
CREDIT: DR EVA JIMENEZ-GURI

Sea urchin larvae raised in high levels of plastic pollution die due to developmental abnormalities, new research shows.

Scientists put fertilised urchin eggs in seawater with varying levels of plastic, and compared the effects of newly made PVC pellets (called nurdles) with fragments collected on beaches.

In all three concentrations tested (1%, 5% and 10% of plastic in seawater), PVC led to significant abnormalities and all urchin larvae died.

Beach-collected fragments at 10% concentration also killed the larvae, which developed no proper shape.

Lower concentrations of beach-collected plastic did not kill the embryos, suggesting newly made plastic – which still contains high levels of additives that can leach out – are more harmful.

Although the concentrations tested in the study are rare in the oceans, they could occur after spills of plastic or in areas like the tide line where pollution accumulates.

The research team – from the Anton Dohrn Zoological Station and National Biodiversity Future Center (Italy), and the University of Exeter (UK) – previously found plastic additives can harm sea urchin larvae, and the new study develops this and reveals how this harm is caused.

“The larvae affected by plastic pollution showed developmental abnormalities including malformation of the skeleton, neural and immune cells,” said Dr Eva Jimenez-Guri, from the Anton Dohrn Zoological Station and the University of Exeter.

“They also showed ‘radialisation’ – meaning they lacked proper symmetrical structure, and were instead largely formless and therefore unable to survive.

“In these larvae, mitochondria (the ‘powerhouses’ of cells) didn’t work properly, and they showed signs of oxidative stress, which damages cells.”

The study reveals the genetic processes behind these abnormalities.

In the case of new PVC nurdles, the damage was caused by high concentrations of zinc that leached into the water.

Larvae exposed 10% PVC pollution developed their gut outside their body, while the 5% and 1% levels also lead to fatal abnormalities.

The beach-collected samples – gathered in Cornwall, UK – did not release high levels of zinc, as most of the additives they contained would already have been released in the sea.

However, such particles are known to collect a variety of organic pollutants, and the release of these pollutants explains the abnormalities seen in this study.

“Our findings point to clear and specific detrimental effects of marine plastic pollution on the development of sea urchin larvae,” said Dr Jimenez-Guri.

“We have identified the genes that are affected by these pollutants, and we know many animal species rely on the same genes for key early stages of development.

“So it’s possible that plastic pollution could cause similar abnormalities in other species, and we are already investigating this in the next stage of our research.

“While the levels of pollution assessed in the study are not common in the ocean, marine plastic pollution continues to increase at a rapid rate – with potentially serious consequences for marine life.”

Dr Jimenez-Guri’s work was funded by a Marie Skłodowska-Curie fellowship.

The paper, published in the journal Science of the Total Environment, is entitled: “Plastic leachate-induced toxicity during sea urchin embryonic development: Insights into the molecular pathways affected by PVC.”

JOURNAL

Science of The Total Environment

DOI

10.1016/j.scitotenv.2022.160901

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Plastic leachate-induced toxicity during sea urchin embryonic development: Insights into the molecular pathways affected by PVC

Screening a puppy’s DNA methylome may help predict how energetic or fearful they will be

Differences in epigenetic DNA methylation predict behavioral differences between dogs better than genetic markers

Peer-Reviewed Publication

FRONTIERS

Anyone who’s ever had a dog knows how different one can be from another. For example, they can be reserved or friendly, playful or calm, fearful or bold, and prone to bark or fetch or not. Research has shown that some of these differences are genetically determined. But even within dog breeds, where line breeding and artificial selection have led to the loss of much of the original genetic variation, the behavior of individuals can differ widely.

Now, researchers show that part of the differences in temperament – in particular their ‘energy’ level and fear-related behaviors – depend on acquired differences in the epigenome. The epigenome, an individual’s unique set of chemical tags on DNA and its associated histone complexes (nucleosomes), can dial the expression of local genes up or down. Because the epigenome is known to depend on age, diet, exercise, training, socialization, and other environmental factors, it can impact the activity and wiring of nerve cells and thus alter behavior.

Corresponding author Dr Matteo Pellegrini, a professor at the University of California at Los Angeles, said: “Here we show that the behavior of dogs is associated with their epigenome, in particular DNA methylation. Our results open the door to using epigenetics to screen and select for desired behavioral traits in companion or service dogs.”

Behavioral questionnaire

Pellegrini and his colleagues quantified the epigenetic, genetic, and behavioral differences between 46 female and male dogs from 31 different breeds, with an age between one and 16 years. Behavioral differences were quantified based on how the owners rated their dog in the Canine Behavioral and Research Assessment Questionnaire (C-BARQ) questionnaire, a widely used standardized tool that consists of 101 questions. The researchers used a form of machine learning, Partial Least Squares (PLS) regression, to identify significant associations between genetic or epigenetic variants and behavioral traits.

The epigenome is known to differ strongly between tissues. In principle, nervous tissue would be the best place to look for associations between behavior and the epigenome. But for ease of collection, the researchers studied the epigenome of epithelial and immune cells obtained from swabs inside the dogs’ cheeks. For this proof-of-concept study, they focused on DNA methylation at 3,059 CG sites, as this is easier to quantify than other types of epigenetic marks, for example methylation or acetylation of histones.

Epigenetics are more informative than genetics for behavior

The results showed that the epigenome was a better predictor of behavior than the genotype at the sites they measured. Even within the most represented breed – Australian shepherds with 12 dogs in the sample – only two of the 930 selected Single-Locus Polymorphisms (SNP) examined were strongly associated with behavioral traits. Two SNPs on chromosome 12 could partly predict a dog’s degree of stranger-directed fear (ie, fear of unfamiliar people).

But when the authors corrected for the potential confounding effect of differences in age, differences in DNA methylation between dogs explained a far greater proportion of observed variation in energy, attention seeking, nonsocial fear, and stranger-directed fear than genetic differences did. These results imply that the epigenome helps to shape behavioral differences in dogs, even in tissues that aren’t part of the nervous system.

Surprising results

“These associations between the DNA methylation of cells in the mouth and dog behaviors were surprising, and suggests that future studies that examine DNA methylation in nerve tissues may identify similar patterns,” said Pellegrini.

“We plan to conduct much larger studies in the future, with the goal of developing biomarkers that allow us to better identify dogs with specific behavioral predispositions.”

He concluded: “Ultimately, we would be very interested in examining the epigenomes of highly specialized dogs such as guide dogs or sled dogs, to be able to assist in the selection of dogs that might be more likely to successfully complete their training.”

JOURNAL

Frontiers in Psychology

DOI

10.3389/fpsyg.2022.1025494

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Association of DNA methylation with energy and fear-related behaviors in canines

ARTICLE PUBLICATION DATE

16-Dec-2022

The first mass screening system for Covid cases has been developed with a sensitivity of 97%

A hydroalcoholic gel with a QR code enables people to access to a test that assesses their ability to identify the smell of the product and eight symptoms of the disease. Using IA techniques, it instantly evaluates the risk of having Covid.

Peer-Reviewed Publication

UNIVERSITAT ROVIRA I VIRGILI

Prototyp of the screening system for Covid cases — IMAGE: PROTOTYP view more
CREDIT: URV

Washing your hands with hydroalcoholic gel, smelling it and using a QR code to answer a short questionnaire. These very simple actions make up the world’s first patented mass screening system for Covid cases. A research group from the Universitat Rovira i Virgili, in conjunction with the Pere Virgili Health Research Institute, has developed this method, which is based on artificial intelligence techniques. The model instantly determines which people have a low, medium or high risk of having the disease at that moment with a sensitivity of 97%. The first prototype of this device has been installed at the entrance to the Sant Joan University Hospital in Reus and the research results have been published in the journal Scientific Reports.

Citrus fruits and apples are two of the first aromas that people with the SARS-CoV-2 virus stop detecting. Anosmia – that’s to say, the loss of the ability to detect smells – has been one of the characteristic symptoms of Covid since the beginning of the pandemic. But it is not the only one. A high temperature, a headache, a cough, discomfort and a sore throat are all signs of the coronavirus but also of a cold or flu. So, without any diagnostic test, how can you know which virus your symptoms are caused by? The system that has been patented is based on a hydroalcoholic gel to which a particular concentration of a citrus essence has been added. “We knew from the results of previous research that this aroma is one of the first that Covid sufferers cannot perceive when they lose their sense of smell,” said Eduard Llobet, a researcher from the URV’s Department of Electronic, Electrical and Automatic Engineering. “We did tests with different concentrations until we determined the one we needed,” he added.

This test was performed on approximately 500 patients who, during the second wave of the pandemic, attended the emergency department of the Sant Joan University Hospital in Reus and the primary care centres in Reus because they had Covid-like symptoms or because they were asymptomatic but had been in close contact of a positive case. They had to rub their hands with the gel and then smell them after three seconds. The result was considered negative if they recognized a citrus fruit, and positive if they couldn’t smell the gel or could not detect a citrus aroma. Once this had been done, the participants in the study had to fill in a short questionnaire with the result of the smell test and other data such as age, gender and the presence or absence of different symptoms. “We gave each symptom a diagnostic value based on our calculations, and there were eight that we regarded as statistically significant for detecting the disease,” explained Youcef Aceli, a researcher at the IISPV, who headed the research. Once the participants had given their answers were given, they were given a PCR test to check the result.

“The system we have developed is based on machine learning and the results of the questionnaire were used to generate a model that enables the mass detection of Covid cases when resources do not allow for diagnostic tests,” said Albert Fernandez, a URV researcher and developer of the algorithm based on artificial intelligence. The data ensure almost total sensitivity (97%), which makes it useful as a method for screening the population.

“The antigen tests on the market have an average sensitivity of 80%, which means that the number of false negatives is 20%. What we have developed is not a diagnostic test, but a screening system that aims to detect the maximum possible number of positives and prevent false negatives,” explained the researchers.

This device is designed to make it clear what risk people have of having Covid, which will help to interrupt the chains of transmission. “The aim is to protect the most vulnerable people and remind people with symptoms of Covid to stay at home or take extreme precautionary measures, such as wearing a mask and following the recommendations of the health authorities,” Aceli says.

The prototype, for which the IISPV and the URV have filed a European patent, is in the process of being put on the market. The aim is to have it installed in hospitals, residences, schools or public transport, so that the people who use it are aware of the risk of spreading the virus they have. The URV’s Valorization Unit and the IISPV’s Innovation and Transfer Unit have assisted the research team to protect the mass screening system.

Reference: Youcef Azeli, Alberto Fernández, Federico Capriles, Wojciech Rojewski, Vanesa Lopez-Madrid, David Sabaté-Lissner, Rosa Maria Serrano, Cristina Rey-Reñones, Marta Civit, Josefina Casellas, Abdelghani El Ouahabi-El Ouahabi, Maria Foglia-Fernández, Salvador Sarrá & Eduard Llobet. A machine learning COVID-19 mass screening based on symptoms and a simple olfactory test. Scientific Reports. DOI: https://www.nature.com/articles/s41598-022-19817-x.

JOURNAL

Scientific Reports

DOI

10.1038/s41598-022-19817-x

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

A machine learning COVID-19 mass screening based on symptoms and a simple olfactory test