A fully liquid Earth’s core also generates a magnetic field

ETH Zurich

Facebook

X
BlueskyMessageWhatsAppEmail

 

image: 

A view of the Earth’s interior around 1 billion years ago: Tangled magnetic field lines inside the core are linked with the Earth’s exterior magnetic field. (Scientifically correct image from a research simulation)

view more 

Credit: ETH Zurich / SUS Tech

In brief:

• Geophysicists from ETH Zurich and SUSTech, China, have demonstrated the dynamo effect of the Earth’s core in a model in which viscosity has no influence, as is the correct physical regime for the Earth.
• The magnetic field was created in the Earth’s early history when its core was completely liquid in a similar way to today.
• This finding helps us to better understand the history of the Earth’s magnetic field and make more precise predictions of its future development.

The Earth is fortunate in having a magnetic field: it protects the planet and its life from harmful cosmic radiation. Other planets in our solar system – such as Mars – are constantly bombarded by charged particles that make life difficult.

Scientists explain the generation of the magnetic field by the mechanism known as the dynamo theory. This states that the ongoing slow cooling of the liquid iron and nickel core drives circular currents of liquid material in the outer core known as convection currents. At the same time, the Earth’s rotation deflects these currents, causing them to flow in a screw-like pattern. These convection currents generate electric currents, which in turn produce magnetic fields and thus most of the Earth’s magnetic field.

However, the theory has a flaw: the Earth’s core was completely liquid before the Earth’s inner core crystallised – around 1 billion years ago. The question is whether the magnetic field could have been generated prior to this time.

A team of three geophysicists from ETH Zurich and SUSTech, China, have come up with an answer to this question in a new study published in the journal Nature.

New model provides the answer

As the Earth’s interior and the processes taking place within it cannot be observed directly, geoscientists study this with the aid of computer models.

The researchers developed a computer model of the Earth with which to simulate whether a completely liquid core could also generate a stable magnetic field. Their simulations were partially calculated on the Piz Daint high-performance computer at the CSCS in Lugano.

In the simulations, the researchers demonstrate the correct physical regime in which the Earth’s core viscosity has no influence on the dynamo effect. This means that the Earth’s magnetic field was generated in the early history of the Earth in a similar way to today.

The research team is the first to successfully minimise the influence of the Earth’s core viscosity to a negligible value in a model. “Until now, no one has ever managed to perform such calculations under these correct physical conditions,” says the study’s lead author, Yufeng Lin.

Understanding the history of the Earth’s magnetic field

“This finding helps us to better understand the history of the Earth’s magnetic field and is useful in interpreting data from the geological past,” says co-author Andy Jackson, Professor of Geophysics at ETH Zurich.

This also places the emergence of life in a different light. Billions of years ago, life apparently benefited from the magnetic shield, which blocked harmful radiation from space, making its development possible in the first place.

The researchers can also use the new findings to study the magnetic fields of other celestial bodies such as the Sun or the planets Jupiter and Saturn.

Indispensable for modern civilisations

The Earth’s magnetic field not only protects life, however; it plays a crucial role in making satellite communications and many other aspects of modern civilisation possible. “It is therefore important to understand how the magnetic field is generated, how it changes over time, and what mechanisms maintain it,” says Jackson. “If we understand how the magnetic field is generated, we can predict its future development.”

The magnetic field has changed its polarity thousands of times throughout the history of the Earth. In recent decades, researchers have also observed a rapid shift of the magnetic north pole toward the geographic north pole. It is essential for our civilisation to understand how magnetism is changing on Earth.

---

Journal

Nature

DOI

10.1038/s41586-025-09334-y 

Method of Research

Computational simulation/modeling

Subject of Research

Not applicable

Article Title

Invariance of dynamo action in an early-Earth model

Article Publication Date

30-Jul-2025

COI Statement

This study was funded in part by an ERC (European Research Commission) Advanced Grant awarded to Andy Jackson, Professor of Geophysics at ETH Zurich in 2019.

21ST CENTURY ALCHEMY

Techniques honed by Kansas nuclear physicists helped detect creation of gold in Large Hadron Collider collisions

University of Kansas

Facebook

WeChatBluesky
Email

 

image: 

ALICE experiment at CERN's Large Hadron Collider, where KU nuclear physicists helped detect gold, briefly, during ultra-peripheral collisions. 

view more 

Credit: CERN

LAWRENCE — Nuclear physicists working at the Large Hadron Collider recently made headlines by achieving the centuries-old dream of alchemists (and nightmare of precious-metals investors): They transformed lead into gold.

At least for a fraction of a second. The scientists reported their results in Physical Reviews.

The accomplishment at the Large Hadron Collider, the 17-mile particle accelerator buried under the French-Swiss border, happened within a sophisticated and sensitive detector called ALICE, a scientific instrument roughly the size of a McMansion.

It was scientists from the University of Kansas, working on the ALICE experiment, who developed the technique that tracked “ultra-peripheral” collisions between protons and ions that made gold in the LHC.

“Usually in collider experiments, we make the particles crash into each other to produce lots of debris,” said Daniel Tapia Takaki, professor of physics and leader of KU’s group at ALICE. “But in ultra-peripheral collisions, we’re interested in what happens when the particles don’t hit each other. These are near misses. The ions pass close enough to interact — but without touching. There’s no physical overlap.”

The ions racing around the LHC tunnel are heavy nuclei with many protons, each generating powerful electric fields. When accelerated, these charged ions emit photons — they shine light.

“When you accelerate an electric charge to near light speeds, it starts shining,” Tapia Takaki said. “One ion can shine light that essentially takes a picture of the other. When that light is energetic enough, it can probe deep inside the other nucleus, like a high-energy flashbulb.”

The KU researcher said during these UPC “flashes” surprising interactions can occur, including the rate event that sparked worldwide attention.

“Sometimes, the photons from both ions interact with each other — what we call photon-photon collisions,” he said. “These events are incredibly clean, with almost nothing else produced. They contrast with typical collisions where we see sprays of particles flying everywhere.”

However, the ALICE detector and the LHC were designed to collect data on head-on collisions that result in messy sprays of particles.

“These clean interactions were hard to detect with earlier setups,” Tapia Takaki said. “Our group at KU pioneered new techniques to study them. We built up this expertise years ago when it was not a popular subject.”

These methods allowed for the news-making discovery that the LHC team transmuted lead into gold momentarily via ultra-peripheral collisions where lead ions lose three protons (turning the speck of lead into a gold speck) for a fraction of a second.

Tapia Takaki’s KU co-authors on the paper are graduate student Anna Binoy; graduate student Amrit Gautam; postdoctoral researcher Tommaso Isidori; postdoctoral research assistant Anisa Khatun; and research scientist Nicola Minafra.

The KU team at the LHC ALICE experiment plans to continue studying the ultra-peripheral collisions. Tapia Takaki said that while the creation of gold fascinated the public, the potential of understanding the interactions goes deeper.

“This light is so energetic, it can knock protons out of the nucleus,” he said. “Sometimes one, sometimes two, three or even four protons. We can see these ejected protons directly with our detectors.”

Each proton removed changes the elements: One gives thallium, two gives mercury, three gives gold.

“These new nuclei are very short-lived,” he said. “They decay quickly, but not always immediately. Sometimes they travel along the beamline and hit parts of the collider — triggering safety systems.”

That’s why this research matters beyond the headlines.

“With proposals for future colliders even larger than the LHC — some up to 100 kilometers in Europe and China — you need to understand these nuclear byproducts,” Tapia Takaki said. “This ‘alchemy’ may be crucial for designing the next generation of machines.”

This work was supported by the U.S. Department of Energy Office of Science, Office of Nuclear Physics.

---

DOI

10.1103/PhysRevC.111.054906 

 

More than telehealth: Social factors shape heart health

Heart health tied not just to habits, but to access and opportunity, study finds

University of Mississippi

Facebook

XLinkedInWeChatBlueskyMessage

Ruaa Al Juboori, assistant professor of public health and data analytics statistician, and Andrew Yockey, assistant professor of public health, analyzed data from 418 counties in Alabama, Georgia, Louisiana, Mississippi and South Carolina. They used mapping and statistical methods to test hypotheses, explore patterns in heart disease rates, and identify key social and structural factors linked to those patterns.

They found that especially high rates of coronary heart disease, or CHD, deaths were found in the Mississippi Delta and parts of western Alabama. These areas often face challenges such as poverty, shortages of health care workers and ongoing health inequalities.

"One of the most promising findings from our spatial analysis was the protective role of health care provider availability, particularly primary care physicians, on coronary heart disease outcomes," said Al Juboori, lead author of the study that was published in the International Journal of Environmental Research and Public Health.

The results indicate that even small increases in the number of primary care physicians in an area can produce a substantial improvement in CHD rates and mortality, she said.

"This highlights the impact that even modest investments in rural health care workforce capacity, through initiatives like loan forgiveness programs or rural residency incentives, could have on improving cardiovascular health," Al Juboori said.

Not all Southern regions were ranked poorly. In fact, some performed better than expected, she said.

"Despite facing structural disadvantages such as low broadband access, high rurality and economic hardship, Washington County, Alabama, stood out in this regard," Al Juboori said. "Despite limited provider density and a high proportion of households without digital access or vehicles, the county reported lower-than-expected CHD mortality."

Treutlen County, Georgia, also stood out with better-than-expected cardiovascular outcomes despite structural challenges, said Neva Agarwala, a researcher at South College and a co-author of the study.

"This may reflect state-supported efforts like the Georgia Rural Health Innovation Center, which expanded telehealth access to over 130 rural clinics," Agarwala said. "The Georgia Department of Public Health also deploys community health workers to provide chronic disease education and support in underserved areas."

"These initiatives help reduce access barriers and promote better health outcomes in rural communities."

A key takeaway from this study is that not all rural areas face the same challenges, Al Juboori said. Some counties have overlapping barriers including low income, aging populations and no access to providers or digital tools, while others may have strengths to build on.

This study revealed that closing the digital divide is essential for expanding telehealth in rural areas.

"In the Deep South counties we studied, approximately 10.3% of households lacked a computer or smartphone, and broadband infrastructure was still underdeveloped in many areas, especially compared to national averages," Al Juboori said. "This means that even where broadband is technically available, many residents are still unable to use telehealth due to affordability or lack of digital readiness."

But technology alone is not enough, she said.

"Telehealth needs to be paired with strong local health care infrastructure," she explained. "Mobile clinics and community health workers can help bridge the gap. Ultimately, telehealth can be part of a hybrid care model that combines digital tools with community-based support."

Yockey suggested that taking inspiration from regions in the West where heart disease rates are especially low can be a good idea.

"Denver, Colorado is a resilient county because everyone is healthy and they have resources," he said. "The cost of living is a little higher, but they have more things to better promote health and social well-being than Mississippi."

According to South Denver Cardiology, Colorado has the third-lowest heart disease rate in the country, the fifth-lowest number of heart disease deaths per 100,000 adults between 45 and 64, and the highest percentage of physically active adults in the country.

"Studying resilient counties with favorable outcomes that outperform expectations can help identify scalable, community-driven strategies to improve health equity," said J. Riley Morgan, of Tupelo, who earned a master's degree in public health in 2024.

Morgan was among several Ole Miss graduate students in public health who assisted with the study. He helped review literature on telehealth and health access in the Deep South.

"Improving health access in Mississippi's rural regions could also reduce long-term health care costs, increase workforce participation and strengthen the state's economy by keeping more residents healthy and able to work," he said.

By 2030, the state will need an additional 364 primary care providers, 24% more than the 2010 workforce, to meet the demands of an aging, growing and increasingly insured population, according to the Robert Graham Center.

"You look at Mississippi – 82 counties, and 80 of them have major health care disparities," Yockey said. "For example, 12 counties in Mississippi have been identified as 'high burden' for cardiovascular disease risk – meaning they rank in the top 25% statewide for obesity, physical inactivity, hypertension and have the lowest levels of health insurance coverage. There's a clear issue.

"I grew up in a very rural environment, so having a rural health care approach really matters. We need a program that blends metropolitan and rural health. Rural counties are being neglected, no matter where you are."

---

Journal

International Journal of Environmental Research and Public Health

DOI

10.3390/ijerph22071020 

Article Title

Telehealth-Readiness, Healthcare Access, and Cardiovascular Health in the Deep South: A Spatial Perspective

 

Borderline democracy? How Polish voters tolerated restrictions of civil liberties to address immigration crisis

New research suggests citizens may accept democratic infringements if policy goals are popular

University of California - Merced

LinkedInWeChatBlueskyMessageWhatsAppEmail

In the face of a growing migration crisis in 2021, the Polish government declared a state of emergency along its border with Belarus, suspending basic civil liberties for citizens in the affected areas. A new study forthcoming in The Journal of Politics investigates whether these restrictions sparked a political backlash at the ballot box — and finds surprisingly little evidence that they did.

Researchers Anil Menon (University of California, Merced) and Paweł Charasz (The Chinese University of Hong Kong, Shenzhen) examined voting behavior before and after the emergency in areas impacted by the restrictions compared to nearby unaffected areas. They focused on Poland’s 2019 and 2023 parliamentary elections, using a statistical method known as difference-in-discontinuities to isolate the effect of the policy.

Their findings: Despite the suspension of rights such as freedom of assembly and movement, voters living under the state of emergency did not significantly punish the ruling Law and Justice party (PiS) at the polls. The estimated drop in vote share was modest —between 0.8 and 1.7 percentage points — and statistically insignificant. The researchers also did not find an effect on turnout or on support for opposition parties.

The results suggest voters may be willing to tolerate restrictions on democratic freedoms if they perceive the government will in turn take decisive action on related issues — in this case, illegal immigration.

"These findings provide one explanation for the global rise of strongman politics and the strategic use of emergency powers by democratic governments," the authors note.

The 2021 emergency followed Belarus’s deliberate funneling of migrants into the European Union, which Poland countered by enforcing a three-month emergency zone with strict movement controls and limited media access. Some restrictions remained for another seven months. Despite public debate and legal challenges, local electoral consequences were minimal.

Charasz and Menon stress that their findings do not imply voters approved of the restrictions, but rather that such measures did not substantially affect support for the incumbents. They call for future research to better understand how voters weigh policy outcomes against democratic costs.

---

Journal

The Journal of Politics

DOI

10.1086/737687 

Method of Research

Data/statistical analysis

Subject of Research

People

Article Title

Borderline Democracy? The Electoral Consequences of the 2021 State of Emergency on the Poland-Belarus Border

 

We might inhale 68,000 lung-penetrating microplastics daily in our homes and cars – 100x previous estimates

In small French study, researchers found surprisingly high concentrations of these 1-10 micrometer particles in air samples of their own homes and cars

PLOS

LinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Indoor microplastic concentrations.

view more 

Credit: Nadiia Yakovenko, CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

New measurements of fine microplastic particles suspended in the air in homes and cars suggest that humans may be inhaling far greater amounts of lung-penetrating microplastics than previously thought. Nadiia Yakovenko and colleagues at the Université de Toulouse, France, present these findings in the open-access journal PLOS One on July 30, 2025.

Prior research has detected tiny fragments of plastic known as microplastics suspended in the air across a wide variety of outdoor and indoor environments worldwide. The ubiquity of these airborne pollutants has raised concerns about their potential health effects, as small-sized inhaled microplastic particles may penetrate the lungs and could pose risks of oxidative stress, immune-system effects, and organ damage. However, prior research on airborne microplastics has mostly focused on larger particles ranging from 20 to 200 micrometers in diameter, which are less likely to penetrate the lungs than particles of 10 micrometers across or less.

To help improve understanding of the risk of microplastic inhalation, Yakovenko and colleagues collected air samples from their own apartments, as well as from their own cars in realistic driving conditions. A technique called Raman spectroscopy enabled them to measure concentrations of microplastics, including those from 1 to 10 micrometers across, in 16 air samples.

They found that the median concentration of detected microplastics in the apartment air samples was 528 particles per cubic meter, and in the cars, 2,238 particles per cubic meter. Ninety-four percent of the detected particles were smaller than 10 micrometers. (While car levels were higher than apartment levels, the difference was not statistically significant because of high variability of microplastic concentration in both environments.)

The researchers then combined their results with previously published data on exposure to indoor microplastics, estimating that adults inhale about 3,200 microplastic particles per day in the range of 10 to 300 micrometers across, and 68,000 particles of 1 to 10 micrometers per day—100 times more than prior estimates for small-diameter exposures.

These findings suggest that health risks due to inhalation of lung-penetrating microplastics may be higher than previously thought. Further research will be needed to confirm and expand on these results.

The authors add: “We found that over 90% of the microplastic particles in indoor air across both homes and cars were smaller than 10 µm, small enough to be inhaled deep into the lungs. This was also the first study to measure microplastics in the car cabin environment, and overall, we detected indoor concentrations up to 100 times higher than previous extrapolated estimates, revealing indoor air as a major and previously underestimated exposure route of fine particulate microplastic inhalation.”

“Everywhere we look, we find microplastics, even in the air we breathe inside our homes and cars. The biggest concern is how small these particles are completely invisible to the naked eye. We inhale thousands of them every day without even realizing it. Deep inside our lungs, microplastics release toxic additives that reach our blood and cause multiple diseases.”

Electron microscope image of a quartz fiber filter with numerous micrometer-sized microplastic indoor dust particles.

Credit

Nadiia Yakovenko, CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

Total suspended MP polymer composition observed in different indoor environments studied.

Credit

Yakovenko et al., 2025, PLOS One, CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

In your coverage, please use this URL to provide access to the freely available article in PLOS One: http://plos.io/44QxPdr

Citation: Yakovenko N, Pérez-Serrano L, Segur T, Hagelskjaer O, Margenat H, Le Roux G, et al. (2025) Human exposure to PM10 microplastics in indoor air. PLoS One 20(7): e0328011. https://doi.org/10.1371/journal.pone.0328011

Author countries: France

Funding: ANR-20-CE34-0014 ATMO-PLASTIC ANR-23-CE34-0012 BUBBLPLAST

---

Journal

PLOS One

DOI

10.1371/journal.pone.0328011 

Method of Research

Observational study

Subject of Research

People

Article Title

Human exposure to PM10 microplastics in indoor air

Article Publication Date

30-Jul-2025

Instagram images could influence public opinion on certain major events

Study finds especially strong correlation between sentiment of anti-war images and user sentiment expressed in later comments

PLOS

Facebook

XLinkedInWeChat

 

image: 

Instagram images could influence public opinion on certain major events.

view more 

Credit: Pixabay, Pexels, CC0 (https://creativecommons.org/publicdomain/zero/1.0/)

A new study of Instagram posts has uncovered strong statistical correlations suggesting that social media images may play a key role in shaping public opinion toward events, with notable social and political effects. Nafiseh Jabbari Tofighi of Istanbul Medipol University, Turkey, and Reda Alhajj of University of Calgary, Canada, Istanbul Medipol University, Turkey, and University of Southern Denmark, Denmark, present these findings in the open-access journal PLOS One on July 30, 2025.

Some prior studies have suggested that images and videos on social media can significantly impact users’ sentiments toward certain sociopolitical topics. However, other studies suggest that such impacts are limited because users typically only process information that aligns with what they already believe.

While both textual data and image-based data have previously been used for research on sociopolitical sentiment, few studies have combined these two data types. To help fill that gap, Tofighi and Alhajj investigated potential links between the sentiments suggested by static images in Instagram posts and the sentiments expressed by users who commented on the posts.

The researchers selected 100 Instagram posts, each with high user engagement and high relevance to one of four sociopolitical movements: Black Live Matter, Women’s March, climate change protests, and anti-war demonstrations. They manually categorized the sentiment of each image as either positive or negative, and they used deep machine learning methods to analyze comments and determine the percentage of comments expressing positive versus negative sentiment.

The analysis showed strong alignment between sentiment scores for the images and the sentiment of later comments, supporting the idea that social media images may significantly influence public sentiment on sociopolitical events.

Images related to anti-war demonstrations had the highest correlations between visual and commenter sentiments, perhaps because of the emotionally charged nature of such images. Images related to climate change protests had lower correlations, perhaps because the impact of such visuals relies on users being more informed about the context. Images related to the Black Lives Matter and Women’s March movements had moderate correlations, perhaps because of broad variations in type of image and user personal backgrounds.

The authors note the potential for misrepresentation in their analysis as AI-generated or synthetic images may exist in the dataset. They call for the development of technology that can detect such content and filter it out of datasets going forward. These findings help set the stage for future research in the field and could help inform activist strategies and efforts to combat misinformation.

  

 

In your coverage, please use this URL to provide access to the freely available article in PLOS One: http://plos.io/45XCQTC

Citation: Jabbari Tofighi N, Alhajj R (2025) Investigating the impact of social media images on users’ sentiments towards sociopolitical events based on deep artificial intelligence. PLoS One 20(7): e0326936. https://doi.org/10.1371/journal.pone.0326936

Author countries: Turkey, Canada, Denmark

Funding: The author(s) received no specific funding for this work.

---

Journal

PLOS One

DOI

10.1371/journal.pone.0326936 

Method of Research

Computational simulation/modeling

Article Title

Investigating the impact of social media images on users’ sentiments towards sociopolitical events based on deep artificial intelligence

Article Publication Date

30-Jul-2025