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The shape of things to come: How spheroid geometry guides multicellular orbiting and invasion

As organisms develop from embryos, groups of cells migrate and reshape themselves to form all manner of complex tissues. There are no anatomical molds shaped like lungs, livers or other tissues for cells to grow into. Rather, these structures form through the coordinated activity of different types of cells as they move and multiply.

No one is sure exactly how cells manage this collective construction of complex tissue, but a study by Brown University engineers could offer some new insights.

The study, published in Nature Physics, looked at how human epithelial cells behave as spherical aggregates confined inside a collagen matrix. The research revealed surprising ways in which cell clusters first rotate collectively within the confined space, then eventually reconfigure their surroundings to allow individual cells to venture out of the sphere.

Microgravity rewires microbial metabolism, limiting space-based manufacturing efficiency

Scientists at the U.S. Naval Research Laboratory (NRL) have completed a spaceflight biology investigation aboard the International Space Station (ISS) that reveals how microgravity fundamentally alters microbial metabolism, limiting the efficiency of biological manufacturing processes critical to future long-duration space missions. The findings were recently published in the journal npj Microgravity.

The Melanized Microbes for Multiple Uses in Space Project (MELSP), launched to the space station in November 2023, examined how microgravity affects the ability of engineered microbes to produce melanin, a multifunctional biopolymer known for its radiation-shielding, antioxidant, and thermal stable properties.

Results from the completed mission show that while microbes remain capable of producing melanin in space, microgravity significantly interferes with substrate transport, cellular stress responses, and metabolic balance, ultimately reducing production efficiency.

Swimming in a shared medium makes particles synchronize without touching

Several years ago, scientists discovered that a single microscopic particle could rock back and forth on its own under a steady electric field. The result was curious, but lonely. Now, Northwestern University engineers have discovered what happens when many of those particles come together. The answer looks less like ordinary physics and more like mystifying, flawlessly timed choreography.

The study appears in the journal Nature Communications.

In the work, the team found that groups of tiny particles suspended in liquid oscillate together, keeping time as though they somehow sense one another’s motion. Nearby particles fall into sync, forming clusters that appear to sway in unison—rocking back and forth with striking coordination.

Collaboration of elementary particles: How teamwork among photon pairs overcomes quantum errors

Some things are easier to achieve if you’re not alone. As researchers from the University of Rostock, Germany have shown, this very human insight also applies to the most fundamental building blocks of nature.

At its very core, quantum mechanics postulates that everything is made out of elementary particles, which cannot be split up into even smaller units. This made Ph.D. candidate Vera Neef, first author of the recent publication “Pairing particles into holonomies,” wonder: “What can two particles only accomplish if they work as a team? Can they jointly achieve something, that is impossible for one particle alone?”

Software allows scientists to simulate nanodevices on a supercomputer

From computers to smartphones, from smart appliances to the internet itself, the technology we use every day only exists thanks to decades of improvements in the semiconductor industry, that have allowed engineers to keep miniaturizing transistors and fitting more and more of them onto integrated circuits, or microchips. It’s the famous Moore’s scaling law, the observation—rather than an actual law—that the number of transistors on an integrated circuit tends to double roughly every two years.

The current growth of artificial intelligence, robotics and cloud computing calls for more powerful chips made with even smaller transistors, which at this point means creating components that are only a few nanometers (or millionths of millimeters) in size. At that scale, classical physics is no longer enough to predict how the device will function, because, among other effects, electrons get so close to each other that quantum interactions between them can hugely affect the performance of the device.

AI makes quantum field theories computable

An old puzzle in particle physics has been solved: How can quantum field theories be best formulated on a lattice to optimally simulate them on a computer? The answer comes from AI.

Quantum field theories are the foundation of modern physics. They tell us how particles behave and how their interactions can be described. However, many complicated questions in particle physics cannot be answered simply with pen and paper, but only through extremely complex quantum field theory computer simulations.

This presents exceptionally complex problems: Quantum field theories can be formulated in different ways on a computer. In principle, all of them yield the same physical predictions—but in radically different ways. Some variants are computationally completely unusable, inaccurate, or inefficient, while others are surprisingly practical. For decades, researchers have been searching for the optimal way to embed quantum theories in computer simulations. Now, a team from TU Wien, together with teams from the U.S. and Switzerland, has shown that artificial intelligence can bring about tremendous progress in this area. Their paper is published in Physical Review Letters.

AI sheds light on mysterious dinosaur footprints

A new app, powered by artificial intelligence (AI), could help scientists and the public identify dinosaur footprints made millions of years ago, a study reveals.

For decades, paleontologists have pondered over a number of ancient dinosaur tracks and asked themselves if they were left by fierce carnivores, gentle plant-eaters or even early species of birds?

Now, researchers and dinosaur enthusiasts alike can upload an image or sketch of a dinosaur footprint from their mobile phone to the DinoTracker app and receive an instant analysis.

From fleeting to stable: Scientists uncover recipe for new carbon dioxide-based energetic materials

When materials are compressed, their atoms are forced into unusual arrangements that do not normally exist under everyday conditions. These configurations are often fleeting: when the pressure is released, the atoms typically relax back to a stable low-pressure state. Only a few very specific materials, like diamond, retain their high-pressure structure after returning to room temperature and atmospheric pressure.

But locking those atomic arrangements in place under ambient conditions could create new classes of useful materials with a wide range of potential applications. One particularly compelling example is energetic materials, which are useful for propellants and explosives.

In a study published in Communications Chemistry, researchers at Lawrence Livermore National Laboratory (LLNL) identified a first-of-its-kind carbon dioxide-equivalent polymer that can be recovered from high-pressure conditions.

Sloshing liquefied natural gas in cargo tanks causes higher impact forces than expected

What happens if liquefied natural gas (LNG) hits the wall of the cargo tanks in a ship? New research from the team of physicist Devaraj van der Meer from the University of Twente, published in the Proceedings of the National Academy of Sciences, shows that much higher pressure peaks can occur during impact than previously assumed. This insight is important for the design and safety of LNG ships and future liquid hydrogen transport systems.

Normally, a thin layer of air prevents a liquid from hitting a surface directly. The gas acts as a cushion and dampens the blow. In LNG ships, that air has been replaced by vapor from the LNG itself. And that vapor can condense back into liquid during impact. As a result, the cushion disappears, and the load on the wall increases sharply.

Watching atoms roam before they decay

Together with an international team, researchers from the Molecular Physics Department at the Fritz Haber Institute have revealed how atoms rearrange themselves before releasing low-energy electrons in a decay process initiated by X-ray irradiation. For the first time, they have gained detailed insights into the timing of the process—shedding light on related radiation damage mechanisms. Their research is published in the Journal of the American Chemical Society.

High-energy radiation, for example in the X-ray range, can cause damage to our cells. This is because energetic radiation can excite atoms and molecules, which then often decay—meaning that biomolecules are destroyed and larger biological units can lose their function. There is a wide variety of such decay processes, and studying them is of great interest in order to better understand and avert radiation damage.

In the study, researchers from the Molecular Physics Department, together with international partners, investigated a radiation-induced decay process that plays a key role in radiation chemistry and biological damage processes: electron-transfer-mediated decay (ETMD). In this process, one atom is excited by irradiation. Afterward, this atom relaxes by stealing an electron from a neighbor, while the released energy ionizes yet another nearby atom.

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