Long-lived contrails usually form in natural ice clouds

Contrails over Jülich, embedded in very thin and therefore barely visible cirrus clouds.
Photo Credit:© Andreas Petzold

Long-lived contrails form predominantly not in cloud-free skies, but within already existing ice clouds. This is the conclusion reached by a team of scientists from Forschungszentrum Jülich, the University of Cologne, the University of Wuppertal, and Johannes Gutenberg University Mainz. Using extensive observational data, the researchers were able, for the first time, to systematically determine the atmospheric conditions under which long-lasting contrails form – whether in cloudless skies, in very thin and barely visible ice clouds, or in more clearly visible ice clouds, known as cirrus clouds. The result: more than 80 percent of all persistent contrails form within pre-existing clouds, mostly within natural cirrus clouds. The effects of this on the climate are not yet clearly understood. The study, now published in Nature Communications, provides important insights for further research – and, beyond that, strong arguments for taking cloud cover into account when planning flight routes adapted to climate considerations.

New study uncovers potential way to prevent breast cancer in premenopausal women

Photo Credit: Angiola Harry

A University of Manchester study funded by Breast Cancer Now and supported by Prevent Breast Cancer, reveals a drug approved for use in other conditions could be repurposed to prevent breast cancer in women before the menopause.

Researchers at the Manchester Breast Centre, based at The University of Manchester, found that blocking the effects of the hormone progesterone, using ulipristal acetate, a drug already used on the NHS, may reduce the risk of breast cancer developing in women before the menopause, with a strong family history of the disease.

Progesterone is a hormone that can drive breast cancer development. It promotes the growth of a type of breast cell, that has the potential to turn into breast cancer. It can also influence the environment inside the breast, making it easier for these healthy cells to transform into cancer cells.

Prime time for fiber optics to take a deep dive into brain circuits

Fiber-optic technology is being refined for brain research. WashU engineers have developed a way to vastly expand the utility of a single fiber-optic line that can fit in the brain.
Image Credit: JJ Ying

Fiber-optic technology revolutionized the telecommunications industry and may soon do the same for brain research.

A group of researchers from Washington University in St. Louis in both the McKelvey School of Engineering and the School of Medicine have created a new kind of fiber-optic device to manipulate neural activity deep in the brain. The device, called PRIME (Panoramically Reconfigurable IlluMinativE) fiber, delivers multi-site, reconfigurable optical stimulation through a single, hair-thin implant.

“By combining fiber-based techniques with optogenetics, we can achieve deep-brain stimulation at unprecedented scale,” said Song Hu, professor of biomedical engineering, who collaborated with the laboratory of Adam Kepecs, professor of neuroscience and psychiatry at WashU Medicine. 

New study revises our picture of the most common planets in the galaxy

A new study finds that many “mini-Neptunes”—perhaps the most common planets in the galaxy—are under so much pressure from their heavy atmospheres that the surface is likely compressed solid. Illustration Credit: NASA/JPL-Caltech/R. Hurt (IPAC)

As telescopes have become more powerful, it’s turned out our solar system is not the only game in town: There are millions of other planets out there in the galaxy. 

But we’re still teasing out clues about what they are actually like. 

One of the puzzles is a kind of planet that appears to be one of the most common types in the universe. Known as “mini-Neptunes” because they run a little smaller than Neptune in our solar system, these planets are made of some mix of rock and metal, with thick atmospheres mostly made of hydrogen, helium, and perhaps water. Strangely, despite their abundance elsewhere, they have no analogue in our own solar system, making the population something of an enigma. 

But a new study published Nov. 5, led by Prof. Eliza Kempton with the University of Chicago, adds a new wrinkle to our best picture yet of these distant worlds.

Ancient mammoth tooth offers clues about Ice Age life in northeastern Canada

Image Credit: Scientific Frontline / AI generated

The re-examination of a 19th-century fossil indicates that woolly mammoths once roamed much farther east than previously believed, proof that an old specimen can still have secrets to reveal

A worn-down mammoth tooth discovered nearly 150 years ago on an island in Nunavut offers new insights into where and how the Ice Age giants lived and died.

A McGill-led study has reclassified the 1878 find, originally thought to be a Columbian mammoth, as an older, cold-adapted woolly mammoth (Mammuthus primigenius), making it the most northeasterly woolly mammoth find ever in North America. The tooth, unearthed on Long Island, Nunavut near the junction of Hudson and James bays, was first described in 1898 by Geological Survey of Canada director Robert Bell.

’Living metal’ could bridge the gap between biological and electronic systems

Liquid metal oxidizes when exposed to air or aquatic environments, deterring electrical current. A new "living metal" composite (seen here in a nanoscale view) developed at Binghamton University includes bacterial endospores and appears to mitigate this problem.
Image Credit: Courtesy of Binghamton University / Provided

Electronics have been transforming from rigid, lifeless systems into adaptive, living platforms capable of seamlessly interacting with biological environments. Researchers at Binghamton University are pioneering “living metal” composites embedded with bacterial endospores, paving the way for dynamic communication and integration between electronic and biological systems.

In a paper recently published in the journal Advanced Functional Materials, Professor Seokheun “Sean” Choi, Maryam Rezaie, PhD ’25, and doctoral student Yang “Lexi” Gao share their potentially groundbreaking study on liquid living metal composites that could redefine the future of bioelectronics.

Choi — a faculty member in the Thomas J. Watson College of Engineering and Applied Science’s Department of Electrical and Computer Engineering — is developing innovative technologies to bridge the gap between electronic and biological systems.

Are there different types of black holes? New method puts Einstein to the test

At the current resolution of telescopes, black holes predicted by different theories of gravity still look very similar. Future telescopes will make the differences more visible, making it possible to distinguish Einstein's black holes from others.
(Image text translation: Einsteinian Black hole and Alternative Black hole)
Image Credit: L. Rezzolla / Goethe University

Images of black holes are more than just fascinating visuals: they could serve as a “testing ground” for alternative theories of gravity in the future. An international team led by Prof. Luciano Rezzolla has developed a new method to examine whether black holes operate according to Einstein’s theory of relativity or other, more exotic theories. To that end, the researchers conducted highly complex simulations and derived measurable criteria that can be tested with future, even sharper telescopes. Over the next few years, this method could reveal whether Einstein’s theories hold true even in the most extreme regions of the universe.

Black holes are considered cosmic gluttons, from which not even light can escape. That is also why the images of black holes at the center of the galaxy M87 and our Milky Way, published a few years ago by the Event Horizon Telescope (EHT) collaboration, broke new ground. “What you see on these images is not the black hole itself, but rather the hot matter in its immediate vicinity,” explains Prof. Luciano Rezzolla, who, along with his team at Goethe University Frankfurt, played a key role in the findings. “As long as the matter is still rotating outside the event horizon – before being inevitably pulled in – it can emit final signals of light that we can, in principle, detect.”

Study paints detailed picture of forest canopy damage caused by ‘heat dome’

Heat dome foliar scorch
Photo Credit: Courtesy of Oregon State University

A satellite imagery analysis shows that the 2021 “heat dome” scorched almost 5% of the forested area in western Oregon and western Washington, turning foliage in canopies from a healthy green to red or orange, sometimes within a matter of hours.

Damage to foliage leads to a range of problems for trees including reduced photosynthesis and increased vulnerability to pests and disease, scientists at Oregon State University say.

The study by researchers at OSU and the U.S. Forest Service identified 293,546 hectares of damaged forest, a total area of more than 1,000 square miles that’s nearly the size of Rhode Island. They took a deep dive into the affected areas to learn the factors that made some stands more vulnerable than others to the extreme heat event experienced by the Pacific Northwest in June 2021.

Researchers decipher mechanism that prevents the loss of brown adipose tissue activity during ageing

From left to right, Tania Quesada-López, Francesc Villarroya, Albert Blasco-Roset, Marta Giralt, Alberto Mestres-Arenas, Joan Villarroya, Aleix Gavaldà-Navarro and Rubén Cereijo.
Photo Credit: Courtesy of University of Barcelona

As the body ages, brown adipose tissue activity decreases, fewer calories are burned, and this can contribute to obesity and certain chronic cardiovascular diseases that worsen with age. A study led by the University of Barcelona has identified a key molecular mechanism in the loss of brown fat activity during ageing. The study opens up new perspectives for designing strategies to boost the activity of this tissue and prevent chronic metabolic and cardiovascular diseases as the population ages.

The paper, published in the journal Science Advances, is led by Professor Joan Villarroya, from the Faculty of Biology and the Institute of Biomedicine of the UB (IBUB) — based at the Barcelona Science Park-UB  — and the CIBER Area for Physiopathology of Obesity and Nutrition  (CIBEROBN). Teams from the Albert Einstein College of Medicine in New York (United States) are also collaborating.

“Rotten egg” gas could be the answer to treating nail infections, say scientists

Nearly half of people aged over 70 suffer from nail infections, which are notoriously difficult to treat.
Photo Credit: Wang Yanwei

Hydrogen sulphide, the volcanic gas that smells of rotten eggs, could be used in a new treatment for tricky nail infections that acts faster but with fewer side effects, according to scientists at the University of Bath and King’s College London (KCL).

Nail infections are mostly caused by fungi and occasionally by bacteria. They are very common, affecting between 4-10% of the global population, rising to nearly half those aged 70 or over.

These infections can lead to complications, particularly in vulnerable groups such as diabetics and the elderly, but are notoriously difficult to treat.

Current treatments include oral antifungals taken in pill form, and topical treatments which are applied directly to the nail.