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Social media feeds: Algorithm redesign could break echo chambers and reduce online polarization
Scroll through social media long enough and a pattern emerges. Pause on a post questioning climate change or taking a hard line on a political issue, and the platform is quick to respond—serving up more of the same viewpoints, delivered with growing confidence and certainty.
That feedback loop is the architecture of an echo chamber: a space where familiar ideas are amplified, dissenting voices fade, and beliefs can harden rather than evolve.
But new research from the University of Rochester has found that echo chambers might not be a fact of online life. Published in IEEE Transactions on Affective Computing, the study argues that they are partly a design choice—one that could be softened with a surprisingly modest change: introducing more randomness into what people see.
New model predicts the melting of free-floating ice in calm water
A pair of US researchers have developed a new model to tackle a deceptively simple problem: how a small block of ice melts while floating in calm water. Using an advanced experimental setup, Daisuke Noto and Hugo Ulloa at the University of Pennsylvania have captured the intricate dynamics that underlie this everyday process—work that could ultimately pave the way for more accurate predictions of melting sea ice. The study has been published in Science Advances.
If you place a block of ice in a glass of water, it will float at the surface and gradually melt. While this scenario seems simple at first glance, the dynamics involved are surprisingly complex: even if the surrounding water is completely still, the flow of heat from the warmer liquid into the colder ice generates motion that disrupts the system.
As the ice melts, it can begin drifting, spinning, or even flipping over. In turn, these motions alter the surrounding flow of water and heat, affecting the overall melting rate and making it remarkably difficult for physicists to predict how long the ice will last.
Reshaping gold leads to new electronic and optical properties
By changing the physical structure of gold at the nanoscale, researchers can drastically change how the material interacts with light—and, as a result, its electronic and optical properties. This is shown by a study from Umeå University published in Nature Communications.
Gold plays a crucial role in modern advanced technology thanks to its unique properties. New research now demonstrates that changing the material’s physical structure—its morphology—can fundamentally enhance both its electronic behavior and its ability to interact with light.
“This might make it possible to improve the efficiency of chemical reactions such as those used in hydrogen production or carbon capture,” says Tlek Tapani, one of the leading researchers behind the study and doctoral student at the Department of Physics.
Lab study suggests longer waves fracture floating ice sheets at lower stress
When waves are moving across ice-covered seas, they can cause sheets of ice to bend and ultimately break. Understanding the processes underlying these wave-induced ice fractures and predicting when they will occur could help to better forecast how climate change will impact the environment and marine ecosystems on Earth.
Researchers at PMMH Lab, ESPCI, CNRS, PSL University, Sorbonne Université and Université Paris Cité recently performed a new laboratory experiment aimed at shedding new light on this phenomenon. The results of this experiment, published in Physical Review Letters, suggest that the stress at which ice sheets break depends on the length of the underlying waves.
“Since 2021, we wanted to study the propagation of ocean waves in floating ice, with laboratory-scale experiments, and in particular the fracture of a thin sheet by a surface wave,” said Stéphane Perrard, senior author of the paper, told Phys.org. “We were later inspired by the work of E. Dumas Lefevbre and D. Dumont, who monitored the fracture of a real sea ice layer by the wake of an icebreaker. To study a small-scale analog of their experiment, we used the concept of scale invariance: the same physical phenomenon can occur at very different scales, as long as the key ingredients are conserved across scales.”
Zebrafish reveal new insights into the biology of autism
In recent decades, the zebrafish has become one of the most valuable model organisms in scientific research. For a variety of reasons, including their genetic similarities to humans, these tiny tropical fish have helped researchers unlock secrets to diseases ranging from muscular dystrophy to melanoma. Now, Yale researchers are hoping the zebrafish will do the same for autism spectrum disorder.
In a new study, a research team generated a database of 520 U.S. Food and Drug Administration (FDA)-approved drugs and their effects on basic larval zebrafish behaviors and then used the database to identify drug candidates that reverse disrupted behaviors in zebrafish carrying mutations in autism risk genes.
These drug candidates, the researchers say, might represent targets for people carrying mutations in specific autism risk genes.
Proton-trapping MNene transforms ammonia production for food security and economic growth
With a new electrochemical synthesis via an electrochemical nitrogen reduction reaction (NRR), achieving carbon-free ammonia production is closer to reality through work from Drs. Abdoulaye Djire and Perla Balbuena, chemical engineering professors at Texas A&M University, and graduate students David Kumar and Hao En Lai. A topic outlined in their recent paper published in the Journal of the American Chemical Society introduces NRR, which produces ammonia in a cleaner and simpler way by using renewable electricity.
The research branches off of the team’s previous work, where they looked further into enabling two-dimensional materials in renewable energy.
“The current process of making ammonia is energy intensive and emits a lot of carbon dioxide, so if you can make ammonia electrochemically, then you can avoid these two negative effects,” Djire said. “During the electrochemical NRR process, water provides the hydrogen atoms, which combine with nitrogen from the air to form ammonia, all powered by electricity.”
Aurora begins final assembly of revolutionary X-65 aircraft
Aurora Flight Sciences said the fuselage of its X-65 experimental aircraft has arrived for final systems integration.
The Boeing subsidiary said teams in Virginia are now installing the aircraft’s electrical, propulsion, and active flow control systems, while wing and tail production continues at its facility in West Virginia. The update marks the program’s transition from major structural assembly into the final integration phase ahead of flight testing.
“The X-65 fuselage has arrived! Our teams are now integrating electrical, propulsion, and AFC systems into the aircraft fuselage in Virginia, while wing and tail manufacturing is advancing at our facility in West Virginia,” the company said.
Swift spacecraft reorientation buys time for reboost mission
WASHINGTON — NASA modified operations of an astrophysics spacecraft in a decaying orbit to buy more time for a mission later this year that will attempt to raise its orbit.
NASA announced in September it selected Katalyst Space to develop a spacecraft that will rendezvous with the Neil Gehrels Swift Observatory and raise its orbit. Swift, launched in 2004, is in a decaying orbit, and the $30 million reboost mission would keep the spacecraft from reentering.
At an astronomy conference in early January, Jamie Kennea, a research professor at Penn State University who is head of Swift’s science operations team, said models projected that Swift’s orbit would decay below 300 kilometers, the minimum altitude for the reboost mission, sometime between mid-October 2026 and January 2027. That provided several months of margin for Katalyst’s Link spacecraft, scheduled to launch as soon as June 1 on a Northrop Grumman Pegasus XL.