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Unusual Plasma Waves Above Jupiter’s North Pole

A spacecraft observes a new oscillation mode in the low-density plasma.

The Juno space probe has spent the past nine years observing Jupiter and its moons. As the spacecraft’s mission draws to a close, the precession of its orbit has caused its closest approach to the gas giant to shift toward the north pole, enabling it to uncover a surprise: an unusual pattern of plasma waves in the planet’s magnetosphere. Now Robert Lysak of the University of Minnesota and his colleagues describe these waves and propose a mechanism for generating them [1]. Their theory offers a new component to include in planetary magnetosphere models and opens a new plasma regime to further exploration.

According to textbook plasma physics, collective waves of electrons in a plasma called Langmuir waves tend to oscillate parallel to magnetic-field lines at a so-called plasma frequency that’s much greater than the ions’ angular frequency around these field lines, their gyrofrequency. Meanwhile, ions tend to oscillate perpendicular to magnetic-field lines as Alfvén waves, with an upper frequency limit corresponding to the ion gyrofrequency. The waves detected by Juno, however, departed from that paradigm: The Alfven waves’ frequency extended only to the plasma frequency, which was less than the ion gyrofrequency. And the waves’ frequency never exceeded the plasma frequency.

Dephasing enabled fast charging of quantum batteries

We propose and analyze a universal method to obtain fast charging of a quantum battery by a driven charger system using controlled, pure dephasing of the charger. While the battery displays coherent underdamped oscillations of energy for weak charger dephasing, the quantum Zeno freezing of the charger energy at high dephasing suppresses the rate of transfer of energy to the battery. Choosing an optimum dephasing rate between the regimes leads to a fast charging of the battery. We illustrate our results with the charger and battery modeled by either two-level systems or harmonic oscillators. Apart from the fast charging, the dephasing also renders the charging performance more robust to detuning between the charger, drive, and battery frequencies for the two-level systems case.


npj Quantum Inf ormation volume 11, Article number: 9 (2025) Cite this article.

Extracellular vesicles from antler blastema progenitor cells reverse bone loss and mitigate aging-related phenotypes in mice and macaques

Antler blastema progenitor cells (ABPCs) are a distinct population of skeletal mesenchymal stem cells found in regenerating deer antlers, with strong stemness and renewal capacity in vitro. Stem cell-derived extracellular vesicles (EVs) are emerging as potential therapeutic candidates that can mediate donor cells’ beneficial effects. Here, we tested the effects of ABPC-derived EVs (EVsABPC) on aging in mice and rhesus macaques (Macaca mulatta). We identified a variety of unique factors in EVsABPC and showed that in vitro, EVsABPC attenuated phenotypes of senescence in bone marrow stem cells. In aged mice and macaques, EVsABPC substantially increased femoral bone mineral density. Further, intravenous EVsABPC improved physical performance, enhanced cognitive function and reduced systemic inflammation in aged mice, while reversing epigenetic age by over 3 months. In macaques, EVABPC treatment was also neuroprotective, reduced inflammation, improved locomotor function and reduced epigenetic age by over 2 years. Our findings position ABPCs as an emerging and practical source of EVs with translational value for healthy aging interventions.


Inspired by the regenerative capacity of deer antlers, Hao and colleagues report that antler blastema progenitor cell-derived extracellular vesicle treatment counteracts bone loss and epigenetic aging and is neuroprotective in mice and macaques.