science

Marked differences between caffeinated, decaffeinated drinks in analysis of more than 130,000 people

Goeppert Mayer and her contemporaries explained these numbers by proposing that protons and neutrons occupy discrete energy levels, or shells. This model, which is still used to interpret many nuclear physics experiments, treats each particle in the nucleus as independent, but our best quantum theories assert that particles within nuclei actually interact strongly.

Jiangming Yao at Sun Yat-sen University in China and his colleagues have now resolved this contradiction and, in the process, elucidated how magic numbers emerge from these interactions.

Yao says the shell model relies on input from experiments and doesn’t encode details of interactions between each particle. Instead, he and his team started their calculations from first principles, which means they mathematically described how particles interact with each other, how they stick together and how much energy is needed to move them apart in more detail.

Women have made gradual inroads into scientific careers. In Spain, they represent 39.6% of research personnel. However, their increased presence does not translate into equal conditions, and the differences that still persist also extend to scientific communication. This is demonstrated by a large-scale study recently published in the journal PLOS Biology. The authors analyzed 36.5 million academic articles and concluded that biomedical and life science research led by women spends more time in the peer-review process than that led by their male colleagues.

The study used a sample of texts indexed in PubMed, the biomedical literature database, and compared the time elapsed between manuscript submission and final acceptance. The results show that studies with women as first authors or corresponding authors experienced this delay.

For researcher David Álvarez-Ponce, a professor at the University of Nevada in the United States, and one of the study’s authors, this delay poses a series of long-term disadvantages for female scientists. “If a person publishes 50 articles during their career, those days they wait multiply. In the end, we’re talking about a significant difference,” he says.

Ana González, director of the Center for Advanced Social Studies at the Spanish National Research Council (CSIC), agrees. For the sociologist, who did not participate in the study, the most obvious consequence is related to women’s professional advancement and the funding of their research. “If publications are delayed, there are fewer articles, which are still the primary means of scientific advancement,” she points out.

From the surface, Chetumal Bay looks almost placid – just a wide sheet of water with no hint of drama underneath. But below that calm is Taam ja’, a massive underwater sinkhole, or “blue hole,” that’s turned into an unexpected mystery for scientists.

At first, the plan seemed straightforward: map it with sonar, get a depth, move on. Instead, the early readings created a bigger problem – what if Taam ja’ isn’t anywhere near as shallow as those first numbers suggested?

The most recent measurements point to a hole that drops far deeper than expected, and the true bottom may still be out of reach...

Mass migration of US scientists to Europe

"According to data from the European Research Council (ERC), the European Union’s premier funding agency for basic research, applications from the United States for its starting, consolidator and advanced grants to individual researchers — worth up to €2.5 million apiece over five years — rose by 120% in its most recent round of calls, compared with an overall rise in applications of 17% (see ‘Choosing Europe’)."
https://www.nature.com/articles/d41586-026-00362-w
@science

Astronomers may have witnessed the birth of a brand-new black hole in our neighboring galaxy, offering one of the clearest glimpses yet of how some stars quietly collapse into these cosmic abysses without the usual fireworks of an explosion.

While scouring archival data from NASA's NEOWISE mission, a team led by Columbia University astronomer Kishalay De discovered that one of the brightest stars in the Andromeda Galaxy mysteriously brightened over a decade ago, faded dramatically and then vanished from view. The star, labeled M31-2014-DS1, lay about 2.5 million light-years from Earth and weighed just 13 times the mass of our sun — relatively lightweight by typical black hole-forming standards, according to De and colleagues' research.

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Exercise pumps up your muscles — but it might also be pumping up your neurons. According to a study published today in Neuron, repeated exercise sessions on a treadmill strengthen the wiring in a mouse’s brain, making certain neurons quicker to activate. This ‘rewiring’ was essential for mice in the study to gradually improve their running endurance.

Betley and his colleagues[...] decided to focus on the ventromedial hypothalamus, a brain region that regulates appetite and blood sugar. The team then zeroed in on a group of neurons in that region that produce a protein called steroidogenic factor 1 (SF1), which is known to play a part in regulating metabolism. A previous study found that the deletion of the gene that codes for SF1 impairs endurance in mice.

Betley’s team monitored the activity of SF1 neurons in mice running on a treadmill and found that these cells were indeed activated by exercise. Interestingly, one group of SF1 neurons became active only after exercise sessions ended. After several training sessions, the number of neurons that were activated post-run, as well as the magnitude of their activation, increased.

When the researchers examined brain slices from mice that had trained consistently over three weeks, they saw changes in the SF1 neurons’ electrical properties compared with mice that had not repeatedly exercised. These changes indicated that the neurons in the trained mice had become easier to activate. They also found that repeated exercise doubled the number of synapses — connections between the neurons — that were ‘excitatory’, or primed to fire off an electrical signal.

Finally, the authors used optogenetics — a technique that can activate or inhibit genetically engineered neurons with light — to ‘switch off’ SF1 neurons in the mice after they exercised. When these neurons were turned off, the mice didn’t improve their running performance over time, becoming exhausted more quickly than mice in which SF1 neurons were not switched off.

The research article itself (open access): Kindel et al.. Exercise-induced activation of ventromedial hypothalamic steroidogenic factor-1 neurons mediates improvements in endurance. Neuron. URL link. The graphical abstract does a very good job of explaining the research

The Trump administration on Thursday revoked a scientific finding that long has been the central basis for U.S. action to regulate greenhouse gas emissions and fight climate change, the most aggressive move by the Republican president to roll back climate regulations.

The rule finalized by the Environmental Protection Agency rescinds a 2009 government declaration known as the endangerment finding that determined that carbon dioxide and other greenhouse gases threaten public health and welfare. The Obama-era finding is the legal underpinning of nearly all climate regulations under the Clean Air Act for motor vehicles, power plants and other pollution sources that are heating the planet.

The repeal eliminates all greenhouse gas emissions standards for cars and trucks and could unleash a broader undoing of climate regulations on stationary sources such as power plants and oil and gas facilities, experts say. Legal challenges are near certain.

https://www.pnas.org/doi/10.1073/pnas.2520328122

Ocean warming is increasing the frequency, extent, and severity of tropical-coral bleaching and mortality. During 2014–2017, marine heatwaves caused the Third Global Coral Bleaching Event. We analyze data from 15,066 reef surveys globally during 2014–2017. Across all surveyed reefs, 80% and 35% experienced moderate or greater (affecting >10% of corals) bleaching and mortality, respectively.

We assess the global extent of coral bleaching and mortality by applying bleaching response curves calibrated from surveyed reefs to predict bleaching globally, based on comprehensive remote-sensing of heat stress. These models predict that 51% and 15% of the world’s coral reefs suffered moderate or greater bleaching and mortality, respectively, during one or multiple years, surpassing damage from any prior global coral bleaching event. Our findings demonstrate that the impacts of ocean warming on coral reefs are accelerating, with the near certainty that ongoing warming will cause large-scale, possibly irreversible, degradation of these essential ecosystems. With heat stress levels during this event surpassing those observed previously, the National Oceanic and Atmospheric Administration developed more extreme Bleaching Alert levels that are now being used during the ongoing Fourth Global Coral Bleaching Event.

https://archive.md/KBCis

Some cuts from the article:

They found that individuals with very short sleep, high inactivity and low moderate to vigorous activity had the highest rates of dementia and evidence of accelerated brain ageing on MRI.

How to stave off dementia when you’re a short sleeper

To figure out your optimal ratio, we should start with a baseline understanding of our sleep.

For instance, are you a short sleeper (who gets less than six hours of sleep) or a normal sleeper (who gets between six and nine hours)?

If you’re a short sleeper, the study found that increasing sleep duration was associated with a lowering of dementia risk when at the expense of inactivity or light activity, but not when at the expense of moderate to vigorous physical activity.

Specifically, increasing sleep by 30 minute instead of engaging in inactivity or light activity was associated with a 9 per cent and 19 per cent reduction in dementia risk, respectively.

A key technique of cognitive behavioral therapy for panic disorder is interoceptive exposure, where patients learn to tolerate the physical effects of panic attacks through repeated simulated exposure. Now, scientists have shown in a randomized controlled trial that brief intermittent intensive exercise is more effective at reducing the severity of panic disorder than relaxation therapy.