Category: 7. Science

  • New mystery “planet” on the horizon? Here’s why planet ‘Y’ could be warping our Solar System

    New mystery “planet” on the horizon? Here’s why planet ‘Y’ could be warping our Solar System

    Why planet Y maybe the new mystery planet–Representative Image

    Ever since the first explorers charted the outer reaches of our Solar System, its true boundaries have remained hazy. While the Voyager probes have gone far into interstellar space, our Sun’s gravitational influence fades gradually, and we lose track of them. But as for the discoveries, far beyond Neptune lies a realm of icy wanderers that are not just remains of space but actually planets!A recent study talks about the evidence of a distortion or “warp” in the orbital plane of TNOs between roughly 80 to 400 astronomical units (AU) from the Sun. This subtle twist could mean the gravitational tug of an as‑yet‑undetected world, or a hypothetical Planet Y.The new study, accepted for publication by Astronomers Amir Siraj, Christopher F. Chyba, and Scott Tremaine, has identified this disturbance in space.

    Planets in Solar system--Representative Image

    Planets in Solar system–Representative Image

    The researchers measured the mean plane of non-resonant TNOs across distances ranging from 50 to 400 AU. They carefully excluded bodies in orbital resonance with Neptune and developed a method to minimize observational bias. Their findings show that between 80 and 200 AU, and more broadly 80 to 400 AU, the TNOs’ orbital plane is tilted by approximately 15° relative to the invariable plane of the Solar System. Statistical analysis shows this warp is unlikely to be a fluke, which means that there’s only about a 2–4% chance it’s coincidental.

    Scientists say there is a planet between the Earth and Mercury!

    If the warp is real, Siraj and his colleagues propose that a planet with a mass between Mercury and Earth, orbiting at 100–200 AU, inclined by more than 10°, could be the culprit. They note that a larger planet, say Earth‑mass or bigger, would also warp the inner region, which isn’t observed yet, this helps narrow down the scenario.

    So, are planets X and Y real?

    So while there have been speculations about the existence of warps in space, the planets have not been found with a full proof discovery as of now. This hypothetical Planet Y differs distinctly from the often-debated Planet Nine. Planet Nine, if it exists, is theorized to be much larger, about several Earth masses, and located far beyond, at hundreds of AU. Planet Y, by contrast, would be closer and more modest in size.

    Planet Earth--Representative Image

    Planet Earth–Representative Image

    The Vera Rubin Observatory’s Legacy Survey of Space and Time (LSST) could soon put this idea to the test. According to IFLScience, they write, “If such a body exists but is not discoverable by LSST due to its on‑sky location (i.e., high ecliptic latitude), LSST will nevertheless elucidate the details of the Kuiper belt mean plane warp induced by the planet.”If Planet Y exists, it’s possible it originated as another rocky embryo in the chaotic early Solar System, scattered outward during planetary formation. Siraj says that our Solar System likely formed with many such Mercury‑mass bodies, most were ejected, but one might still lurk far out there.Photos: Canva


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  • Scientists Unlock Quantum Computing Power by Entangling Vibrations in a Single Atom

    Scientists Unlock Quantum Computing Power by Entangling Vibrations in a Single Atom

    Artist’s impression of the entangled logic gate built by University of Sydney quantum scientists. Credit: Emma Hyde/University of Sydney

    Physicists at the University of Sydney have achieved a breakthrough in quantum computing by creating a universal logic gate inside a single atom.

    Using a powerful error-correcting system known as the Gottesman-Kitaev-Preskill (GKP) code — often called the “Rosetta Stone” of quantum computing — they managed to entangle vibrations of a trapped ion. This achievement drastically reduces the number of physical qubits needed, tackling one of the biggest hurdles in scaling quantum computers and bringing practical, large-scale quantum machines closer to reality.

    Battling Quantum Errors at Scale

    Building a large, reliable quantum computer is one of science’s toughest challenges. The main obstacle is the random errors that occur when quantum bits, or qubits, perform their operations.

    To make progress, researchers have developed ways of encoding qubits so that some can be used to detect and correct errors in others. This allows a smaller group of qubits to function correctly and deliver meaningful results.

    However, the more logical qubits are added, the more physical qubits are needed to support them. The requirements grow so quickly that scaling up to a truly useful quantum computer turns into a massive engineering nightmare.

    Tingrei Tan and Vassili Matsos
    Dr. Tingrei Tan (left) and his PhD student Vassili Matsos inspect the Paul trap used in this experiment in the Quantum Control Laboratory at the University of Sydney Nano Institute. Credit: Fiona Wolf/University of Sydney

    Breakthrough at the University of Sydney

    Researchers at the Quantum Control Laboratory within the University of Sydney Nano Institute have now taken a major step forward. For the first time, they have demonstrated a kind of quantum logic gate that requires far fewer physical qubits to function.

    Their approach involved constructing an entangling logic gate inside a single atom, using an advanced error-correcting code often described as the “Rosetta stone” of quantum computing. This code has earned its nickname because it converts smooth, continuous quantum oscillations into discrete, digital-like states. That translation makes it easier to spot and correct mistakes, while also providing a compact and efficient way to encode logical qubits.

    GKP Codes: A Rosetta Stone for Quantum Computing

    This curiously named Gottesman-Kitaev-Preskill (GKP) code has for many years offered a theoretical possibility for significantly reducing the physical number of qubits needed to produce a functioning ‘logical qubit’. Albeit by trading efficiency for complexity, making the codes very difficult to control.

    Research published today in Nature Physics demonstrates this as a physical reality, tapping into the natural oscillations of a trapped ion (a charged atom of ytterbium) to store GKP codes and, for the first time, realising quantum entangling gates between them.

    Tingrei Tan
    Sydney Horizon Fellow Dr. Tingrei Tan at the University of Sydney Nano Institute. Credit: Fiona Wolf/University of Sydney

    Led by Sydney Horizon Fellow Dr. Tingrei Tan at the University of Sydney Nano Institute, scientists have used their exquisite control over the harmonic motion of a trapped ion to bridge the coding complexity of GKP qubits, allowing a demonstration of their entanglement.

    “Our experiments have shown the first realisation of a universal logical gate set for GKP qubits,” Dr. Tan said. “We did this by precisely controlling the natural vibrations, or harmonic oscillations, of a trapped ion in such a way that we can manipulate individual GKP qubits or entangle them as a pair.”

    Quantum Logic Gate and Software Innovation

    A logic gate is an information switch that allows computers – quantum and classical – to be programmable to perform logical operations. Quantum logic gates use the entanglement of qubits to produce a completely different sort of operational system to that used in classical computing, underpinning the great promise of quantum computers.

    First author Vassili Matsos is a PhD student in the School of Physics and Sydney Nano. He said: “Effectively, we store two error-correctable logical qubits in a single trapped ion and demonstrate entanglement between them.

    “We did this using quantum control software developed by Q-CTRL, a spin-off start-up company from the Quantum Control Laboratory, with a physics-based model to design quantum gates that minimise the distortion of GKP logical qubits, so they maintain the delicate structure of the GKP code while processing quantum information.”

    Vassili Matsos
    Lead author and PhD student Vassili Matsos looking at the Paul trap quantum computing device in the Quantum Control Laboratory at the University of Sydney. Credit: Fiona Wolf/University of Sydney

    A Milestone in Quantum Technology

    What Mr Matsos did is entangle two ‘quantum vibrations’ of a single atom. The trapped atom vibrates in three dimensions. Movement in each dimension is described by quantum mechanics and each is considered a ‘quantum state’. By entangling two of these quantum states realised as qubits, Mr Matsos created a logic gate using just a single atom, a milestone in quantum technology.

    This result massively reduces the quantum hardware required to create these logic gates, which allow quantum machines to be programmed.

    Dr. Tan said, “GKP error correction codes have long promised a reduction in hardware demands to address the resource overhead challenge for scaling quantum computers. Our experiments achieved a key milestone, demonstrating that these high-quality quantum controls provide a key tool to manipulate more than just one logical qubit.

    “By demonstrating universal quantum gates using these qubits, we have a foundation to work towards large-scale quantum-information processing in a highly hardware-efficient fashion.”

    Towards Scalable, Efficient Quantum Machines

    Across three experiments described in the paper, Dr. Tan’s team used a single ytterbium ion contained in what is known as a Paul trap. This uses a complex array of lasers at room temperature to hold the single atom in the trap, allowing its natural vibrations to be controlled and utilised to produce the complex GKP codes.

    This research represents an important demonstration that quantum logic gates can be developed with a reduced physical number of qubits, increasing their efficiency.

    Reference: “Universal quantum gate set for Gottesman–Kitaev–Preskill logical qubits” by V. G. Matsos, C. H. Valahu, M. J. Millican, T. Navickas, X. C. Kolesnikow, M. J. Biercuk and T. R. Tan, 21 August 2025, Nature Physics.
    DOI: 10.1038/s41567-025-03002-8

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  • Honeybee supplements could protect an essential insect as climate stresses soar – Genetic Literacy Project

    1. Honeybee supplements could protect an essential insect as climate stresses soar  Genetic Literacy Project
    2. Engineered yeast provides rare but essential pollen sterols for honeybees  Nature
    3. Scientists found the missing nutrients bees need — Colonies grew 15-fold  ScienceDaily
    4. Engineered bee diets can help protect global food security  Earth.com
    5. Revolutionary Superfood for Bees Could Save Honey Bee Populations from Extinction  Indian Defence Review

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  • Moon phase today explained: What the moon will look like on August 25, 2025

    Moon phase today explained: What the moon will look like on August 25, 2025

    For the next few nights, the moon will be getting brighter and brighter until we reach the full moon. We’re on day two of the lunar cycle, a series of eight unique phases of the moon’s visibility. The whole cycle takes about 29.5 days, according to NASA, and these different phases happen as the Sun lights up different parts of the moon whilst it orbits Earth. 

    So let’s see what’s happening with the moon tonight, Aug. 25.

    What is today’s moon phase?

    As of Monday, Aug. 25, the moon phase is Waxing Crescent, and only 5% will be lit up to us on Earth, according to NASA’s Daily Moon Observation.

    It’s only day two of the lunar cycle, so there’s still not enough of the moon lit up to see anything on its surface, so keen moon gazers will need to wait a few more days.

    When is the next full moon?

    The next full moon will be on Sept. 7. The last full moon was on Aug. 9.

    What are moon phases?

    According to NASA, moon phases are caused by the 29.5-day cycle of the moon’s orbit, which changes the angles between the Sun, Moon, and Earth. Moon phases are how the moon looks from Earth as it goes around us. We always see the same side of the moon, but how much of it is lit up by the Sun changes depending on where it is in its orbit. This is how we get full moons, half moons, and moons that appear completely invisible. There are eight main moon phases, and they follow a repeating cycle:

    Mashable Light Speed

    New Moon – The moon is between Earth and the sun, so the side we see is dark (in other words, it’s invisible to the eye).

    Waxing Crescent – A small sliver of light appears on the right side (Northern Hemisphere).

    First Quarter – Half of the moon is lit on the right side. It looks like a half-moon.

    Waxing Gibbous – More than half is lit up, but it’s not quite full yet.

    Full Moon – The whole face of the moon is illuminated and fully visible.

    Waning Gibbous – The moon starts losing light on the right side.

    Last Quarter (or Third Quarter) – Another half-moon, but now the left side is lit.

    Waning Crescent – A thin sliver of light remains on the left side before going dark again.

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  • Scientists discover flaws that make electronics faster, smarter, and more efficient

    Scientists discover flaws that make electronics faster, smarter, and more efficient

    Scientists have turned a longstanding challenge in electronics — material defects — into a quantum-enhanced solution, paving the way for new-generation ultra-low-power spintronic devices.

    Spintronics, short for “spin electronics,” is a field of technology that aims to go beyond the limits of conventional electronics. Traditional devices rely only on the electric charge of electrons to store and process information. Spintronics takes advantage of two additional quantum properties: spin angular momentum, which can be imagined as a built-in “up” or “down” orientation of the electron, and orbital angular momentum, which describes how electrons move around atomic nuclei. By using these extra degrees of freedom, spintronic devices can store more data in smaller spaces, operate faster, consume less energy, and retain information even when the power is switched off.

    A longstanding challenge in spintronics has been the role of material defects. Introducing imperfections into a material can sometimes make it easier to “write” data into memory bits by reducing the current needed, but this typically comes at a cost: electrical resistance increases, spin Hall conductivity declines, and overall power consumption goes up. This trade-off has been a major obstacle to developing ultra-low-power spintronic devices.

    Now, the Flexible Magnetic-Electronic Materials and Devices Group from the Ningbo Institute of Materials Technology and Engineering (NIMTE) of the Chinese Academy of Sciences have found a way to turn this problem into an advantage. Their study, published in Nature Materials, focused on the orbital Hall effect in strontium ruthenate (SrRuO3), a transition metal oxide whose properties can be finely tuned. This quantum phenomenon causes electrons to move in a way determined by their orbital angular momentum.

    Using custom-designed devices and precision measurement techniques, the researchers uncovered an unconventional scaling law that achieves a “two birds with one stone” outcome: Defect engineering simultaneously boosts both orbital Hall conductivity and orbital Hall angle, a stark contrast to conventional spin-based systems.

    To explain this finding, the team linked it to the Dyakonov-Perel-like orbital relaxation mechanism. “Scattering processes that typically degrade performance actually extend the lifetime of orbital angular momentum, thereby enhancing orbital current,” said Dr. Xuan Zheng, a co-first author of the study.

    “This work essentially rewrites the rulebook for designing these devices,” said Prof. Zhiming Wang, a corresponding author of the study. “Instead of fighting material imperfections, we can now exploit them.”

    Experimental measurements confirm the technology’s potential: tailored conductivity modulation yielded a threefold improvement in switching energy efficiency.

    This study not only provides new insights into orbital transport physics but also redefines design strategies for energy-efficient spintronics.

    This study received support from the National Key Research and Development Program of China, the National Natural Science Foundation of China, and other funding bodies.

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  • Scientists discover new phenomenon in chiral symmetry breaking

    Scientists discover new phenomenon in chiral symmetry breaking

    Researchers at The University of Osaka have discovered a new type of chiral symmetry breaking (CSB) in an organic crystalline compound. This phenomenon, involving a solid-state structural transition from an achiral to a chiral crystal, represents a significant advance in our understanding of chirality and offers a simplified model to study the origin of homochirality. This transformation also activates circularly polarized luminescence, enabling new optical materials with tunable light properties.

    Novel spontaneous chiral symmetry breaking with in a single crystal

    Ryusei Oketani et al., Spontaneous chiral symmetry breaking in a single crystal, Chemical Science 2025, Ryusei Oketani et al., Spontaneous chiral symmetry breaking in a single crystal, Chemical Science

    Chirality, or “handedness,” is a fundamental property of objects, from galaxies to molecules, and plays a crucial role in biological systems. However, chiral compounds in living organisms such as sugars and amino acids, exist almost exclusively in a single form. This phenomenon, known as “biological homochirality,” has long puzzled scientists, and its underlying mechanism remains elusive. Understanding how a preference for one chiral form over the other arises is crucial for comprehending the origin of life itself.

    Previously, two types of CSB phenomena, preferential enrichment and Viedma ripening, have been observed in solutions. However, the complexity of these solution-based systems makes it challenging to pinpoint the precise mechanisms driving CSB. The University of Osaka team’s discovery of a solid-state CSB provides a drastically simplified model for studying this phenomenon. They found that a chiral phenothiazine derivative can transition from an achiral crystalline form to a chiral one while maintaining single crystallinity. This transition involves the inversion of molecular chirality within the crystal lattice without any external influence such as solvents or impurities.

    This unique solid-state CSB offers significant advantages for studying the fundamental principles governing chiral selection. The simplicity of the system allows for detailed structural analysis using techniques like X-ray diffraction, enabling researchers to visualize the molecular movements during the transition. This provides valuable insights into the dynamics of CSB, potentially revealing the underlying mechanisms responsible for homochirality in biological systems. Furthermore, the transition triggers a “turn-on” of circularly polarized luminescence (CPL), opening up possibilities for developing novel optical materials with switchable CPL properties.

    This discovery has profound implications for understanding the origin of homochirality and its role in the development of life. Furthermore, this research could pave the way for the development of advanced materials with tailored chiral properties for applications in pharmaceuticals, electronics, and other fields.

    “It’s fascinating how life is composed of only one enantiomer of amino acids, and how this chirality manifests in our bodies,” stated Dr. Ryusei Oketani at the University of Osaka, who led the research. “This study represents a major step toward understanding how chiral molecules become biased towards one form and how their assembled structures develop. While this seems like fundamental research, chiral molecules are key components of pharmaceuticals and next-generation materials. This work provides a foundation for efficiently producing these essential substances.”

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  • Scientists Create Liquid Carbon in the Lab for the First Time

    Scientists Create Liquid Carbon in the Lab for the First Time

    Researchers have been able to measure liquid carbon experimentally for the first time. They combined a high-power laser with the ultrashort X-ray laser flash of the European XFEL. Credit: HZDR / M. Künsting

    Researchers have completed a groundbreaking experiment at the European XFEL.

    An international team of scientists, led by the University of Rostock and the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), set out to investigate matter under extreme pressure. In 2023, they used the high-power DIPOLE 100-X laser at the European XFEL for the very first time, achieving remarkable results. Their groundbreaking experiment successfully captured the behavior of liquid carbon, a feat never before accomplished, as reported in the journal Nature.

    Liquid carbon occurs naturally inside planets and could play a crucial role in future energy technologies such as nuclear fusion. Yet until now, researchers knew very little about this elusive state. The challenge lies in the fact that carbon does not melt under normal conditions. Instead, it bypasses the liquid phase entirely and turns directly into gas.

    To transform into a liquid, carbon requires extreme pressures combined with temperatures of about 4,500 degrees Celsius, the highest melting point of any known material. Containing such conditions in a laboratory setting has long been impossible because no physical container could survive them.

    Laser compression provided the breakthrough. By delivering an intense, short burst of energy, the DIPOLE 100-X laser was able to convert solid carbon into liquid for only fractions of a second. The true challenge was capturing data during that fleeting moment. Thanks to the unique capabilities of the European XFEL, the world’s most powerful X-ray laser located in Schenefeld near Hamburg, researchers were finally able to make those measurements. Its ultrashort X-ray pulses made it possible to probe the liquid state in real time, turning a once unimaginable experiment into reality.

    Unique measuring technology in this combination

    The unique combination of the European XFEL with the high-performance laser DIPOLE100-X was crucial for the success of the experiment. It was developed by the British Science and Technology Facilities Council and made available to scientists from all over the world by the HIBEF User Consortium (Helmholtz International Beamline for Extreme Fields). A community of leading international research institutions at the HED-HIBEF (High Energy Density) experimental station at the European XFEL has now combined powerful laser compression with ultrafast X-ray analysis and large-area X-ray detectors for the first time.

    In the experiment, the high-energy pulses of the DIPOLE100-X laser drive compression waves through a solid carbon sample and liquefy the material for nanoseconds, that is, for a billionth of a second. During this nanosecond, the sample is irradiated with the ultrashort X-ray laser flash of the European XFEL. The carbon atoms scatter the X-ray light – similar to the way light is diffracted by a grating. The diffraction pattern allows inferences to be drawn about the current arrangement of the atoms in the liquid carbon.

    The whole experiment only lasts a few seconds but is repeated many times: every time with a slightly delayed x-ray pulse or under slightly different pressure and temperature conditions. Many snapshots combine to make a movie. Researchers have thus been able to trace the transition from solid to liquid phase one step at a time.

    Water-like structure and accurate melting point determined

    The measurements revealed that with four nearest neighbors each, the systemics of liquid carbon are similar to solid diamond. “This is the first time we have ever been able to observe the structure of liquid carbon experimentally. Our experiment confirms the predictions made by sophisticated simulations of liquid carbon. We are looking at a complex form of liquid, comparable to water, that has very special structural properties,” explains the head of the research collaboration’s Carbon Working Group, Prof. Dominik Kraus from the University of Rostock and HZDR.

    The researchers also managed to precisely narrow down the melting point. Up to now, the theoretical predictions on the structure and melting point had diverged significantly. But precise knowledge is crucial for planet modelling and certain concepts for power generation through nuclear fusion.

    The first DIPOLE experiment at the European XFEL also ushers in a new era in measuring matter under high pressure, as HED group leader, Dr. Ulf Zastrau, emphasizes, “We now have the toolbox to characterize matter under highly exotic conditions in incredible detail.” And the experiment’s potential is far from being exhausted. In the future, results that currently take several hours’ experiment time could be available in a few seconds – as soon as the complex automatic control and data processing work fast enough.

    Reference: “The structure of liquid carbon elucidated by in situ X-ray diffraction” by D. Kraus, J. Rips, M. Schörner, M. G. Stevenson, J. Vorberger, D. Ranjan, J. Lütgert, B. Heuser, J. H. Eggert, H.-P. Liermann, I. I. Oleynik, S. Pandolfi, R. Redmer, A. Sollier, C. Strohm, T. J. Volz, B. Albertazzi, S. J. Ali, L. Antonelli, C. Bähtz, O. B. Ball, S. Banerjee, A. B. Belonoshko, C. A. Bolme, V. Bouffetier, R. Briggs, K. Buakor, T. Butcher, V. Cerantola, J. Chantel, A. L. Coleman, J. Collier, G. W. Collins, A. J. Comley, T. E. Cowan, G. Cristoforetti, H. Cynn, A. Descamps, A. Di Cicco, S. Di Dio Cafiso, F. Dorchies, M. J. Duff, A. Dwivedi, C. Edwards, D. Errandonea, S. Galitskiy, E. Galtier, H. Ginestet, L. Gizzi, A. Gleason, S. Göde, J. M. Gonzalez, M. G. Gorman, M. Harmand, N. J. Hartley, P. G. Heighway, C. Hernandez-Gomez, A. Higginbotham, H. Höppner, R. J. Husband, T. M. Hutchinson, H. Hwang, D. A. Keen, J. Kim, P. Koester, Z. Konôpková, A. Krygier, L. Labate, A. Laso Garcia, A. E. Lazicki, Y. Lee, P. Mason, M. Masruri, B. Massani, E. E. McBride, J. D. McHardy, D. McGonegle, C. McGuire, R. S. McWilliams, S. Merkel, G. Morard, B. Nagler, M. Nakatsutsumi, K. Nguyen-Cong, A.-M. Norton, N. Ozaki, C. Otzen, D. J. Peake, A. Pelka, K. A. Pereira, J. P. Phillips, C. Prescher, T. R. Preston, L. Randolph, A. Ravasio, D. Santamaria-Perez, D. J. Savage, M. Schölmerich, J.-P. Schwinkendorf, S. Singh, J. Smith, R. F. Smith, J. Spear, C. Spindloe, T.-A. Suer, M. Tang, M. Toncian, T. Toncian, S. J. Tracy, A. Trapananti, C. E. Vennari, T. Vinci, M. Tyldesley, S. C. Vogel, J. P. S. Walsh, J. S. Wark, J. T. Willman, L. Wollenweber, U. Zastrau, E. Brambrink, K. Appel and M. I. McMahon, 21 May 2025, Nature.
    DOI: 10.1038/s41586-025-09035-6

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  • Culture-free detection of bacteria from blood for rapid sepsis diagnosis

    Culture-free detection of bacteria from blood for rapid sepsis diagnosis

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  • Breathing Crystal Breakthrough Could Revolutionize Clean Energy

    Breathing Crystal Breakthrough Could Revolutionize Clean Energy

    Scientists develop of a special type of crystal with oxygen breathing abilities, which could be used in clean energy technologies and next-generation electronics. Credit: Prof. Hyoungjeen Jeen from Pusan National University, Korea

    Scientists in Korea and Japan have unveiled a remarkable “breathing” crystal that can repeatedly absorb and release oxygen, almost like living lungs.

    Unlike earlier fragile materials, this crystal is stable, reversible, and functions under mild conditions, making it a game-changer for clean energy and smart technologies.

    Crystal That Breathes: A Breakthrough in Clean Energy Materials

    A group of researchers in Korea and Japan has identified a completely new kind of crystal that can actually “breathe.” The material is able to take in and release oxygen over and over again at relatively low temperatures. This unusual property could open the door to major advances in clean energy systems, including fuel cells, smart windows that regulate heat, and next-generation thermal devices.

    The material is a specially engineered metal oxide made of strontium, iron, and cobalt. What makes it remarkable is its resilience: when heated in a simple gas environment, the crystal lets go of oxygen and then draws it back in without breaking down. This cycle can be repeated many times, making the crystal well suited for practical technologies.

    Oxygen Breathable Crystal
    Researchers develop a new kind of crystal that can release and absorb oxygen at low temperatures. (Left) oxygen absorbed SrFe0.5Co0.5O2.5 and (right) oxygen released SrFe0.5Co0.5O2.25. Credit: Prof. Hyoungjeen Jeen from Pusan National University, Korea

    From Lab Discovery to Real-World Potential

    The remarkable research was led by Professor Hyoungjeen Jeen of the Department of Physics at Pusan National University in Korea, in collaboration with Professor Hiromichi Ohta of the Research Institute for Electronic Science at Hokkaido University in Japan. Their results were published in Nature Communications on August 15, 2025.

    “It is like giving the crystal lungs and it can inhale and exhale oxygen on command,” says Prof. Jeen. The ability to control oxygen in this way is vital for devices such as solid oxide fuel cells, which can generate electricity from hydrogen with very low emissions. It is also important for thermal transistors, which channel heat in the same way that switches guide electricity, and for smart windows that can automatically adjust how much heat passes through them depending on outside conditions.

    Why This Material Stands Apart

    Until now, most materials that could do this kind of oxygen control were too fragile or operated only at harsh conditions, such as extremely high temperatures. This new material works under milder conditions and remains stable.

    “This finding is striking in two ways: only cobalt ions are reduced, and the process leads to the formation of an entirely new but stable crystal structure,” explains Prof. Jeen (see the figure above). They also showed that the material could return to its original form when oxygen was reintroduced, proving that the process is fully reversible.

    “This is a major step towards the realization of smart materials that can adjust themselves in real time,” says Prof. Ohta. “The potential applications range from clean energy to electronics and even eco-friendly building materials.”

    Reference: “Selective reduction in epitaxial SrFe0.5Co0.5O2.5 and its reversibility” by Joonhyuk Lee, Yu-Seong Seo, Krishna Chaitanya Pitike, Gowoon Kim, Sangkyun Ryu, Hyeyun Chung, Su Ryang Park, Sangmoon Yoon, Younghak Kim, Valentino R. Cooper, Hiromichi Ohta, Jinhyung Cho and Hyoungjeen Jeen, 15 August 2025, Nature Communications.
    DOI: 10.1038/s41467-025-62612-1

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  • Honeybee-Gilliamella synergy in carbohydrate metabolism enhances host thermogenesis in cold acclimation

    Honeybee-Gilliamella synergy in carbohydrate metabolism enhances host thermogenesis in cold acclimation

    Gilliamella is most significantly enriched in cold-adapted honeybee guts

    We performed metagenome shotgun sequencing on the two cold-resistant honeybees (A. mellifera & A. cerana) and four tropical honeybees (dwarf honeybees A. andreniformis, A. florea, and giant honeybees A. dorsata, A. laboriosa). A total of 70 samples from 168 bee hindguts were obtained from Jilin and Yunnan Provinces, China (Fig. 1B, Fig. 2A, Fig. S1a, Supplementary Data 1) and used to investigate the characteristic gut microbiota of cold-adapted honeybees. The gut microbiota composition confidently divided the six honeybee species into three distinct groups (partial least squares test: Q2Y = 0.783), in line with their phylogenetic relationships (Fig. 2A, Fig. S1b, c). To test whether the gut microbiota composition is influenced by cold climate, independent of host phylogeny, we need to identify which bacterial members are associated with cold tolerance. Core bacteria, Gilliamella, Apibacter, Frischella, Bartonella, and Snodgrassella have contributed mainly to the partition and clustering of the cold-adapted bee group (Fig. 2A). Among these, Gilliamella was barely detected in dwarf bees (Fig. S1b), whereas it was most significantly enriched (Fig. 2B) in the cold-resistant bees, despite typically occurring in the giant honeybees. In contrast, the gram-positive bacteria Lactobacillus and Bifidobacterium predominated in the gut of dwarf honeybees, while Gammaproteobacteria and Bacteroidota, such as Dysgonomonas and Apibacter, outcompeted others in giant honeybees.

    Fig. 2: Gilliamella is most significantly enriched in cold-adapted honeybee hindguts, promoting host thermogenesis.

    A Principal component analysis of gut bacteriome showing bacteria most strongly separating different bees. B Significantly enriched gut bacteria identified in the three honeybee subgenera. LDA: linear discriminant analysis. C Apis cerana workers with (Gc) or without (GF) Gilliamella colonization were subject to thermo imaging after cold exposure (10 °C) for 30 min. AV, average temperature for the framed area; HS and CS denote the highest and lowest temperatures for the entire area, respectively. D The same sets of bees were measured for abdominal temperature after 4 h cold exposure, using a thermocouple (the needle-like instrument touching the bee’s abdomen, as shown in the right photograph of the middle insert). Acer, A. cerana; Amel, A. mellifera; Ador, A. dorsata; Alab, A. laboriosa; Aand, A. andreniformis; Aflo, A. florea.

    Gilliamella colonization improves host heat production and cold tolerance

    To determine the potential impact of Gilliamella on honeybees’ cold resistance, we compared A. cerana workers monocolonized by Gilliamella to germ-free controls, measuring their cold tolerance at 10 °C. On day 8 post-inoculation, as detected by colony-forming unit (CFU) count, the Gilliamella strain B3835 stably colonized the bee hindguts at densities of 107–108 cells per gut (Fig. S1d). When exposed to the cold condition for 30 min, Gilliamella-colonized groups remained active, while the germ-free groups became immobilized (Supplementary Movie 1). The bees sustained a higher body temperature when colonized with Gilliamella (as measured by thermal imaging, Fig. 2C). This difference remained significant after four hours of cold exposure as examined by the abdominal temperatures using a thermocouple (Fig. 2D). In contrast, the colonization of a Lactobacillus strain isolated from A. andreniformis did not improve A. mellifera thermogenesis (Fig. S1e), indicating that not all honeybee gut bacteria can enhance host cold-tolerance. These results indicate that Gilliamella increased heat production in the host, thereby enhancing cold tolerance.

    Gilliamella excels in producing key energy substrates: pyruvate and glucose

    To evaluate the capacity of Gilliamella in its potential contribution to host thermogenesis, we inspected 149 Gilliamella genomes, as well as 17 Lactobacillus and 28 Bifidobacterium genomes (Fig. 3A, Fig. S2, 3, Supplementary Data 1). Among all core gut bacteria derived from western honeybees, Gilliamella was experimentally shown to be superior in producing pyruvate and cross-feed Snodgrassella24. Hence, we explored the underlying metabolic pathways producing energy substrates required by thermogenesis, such as pyruvate25. Our results showed that besides glycolysis, all Gilliamella strains derived from cold-adapted honeybees can produce pyruvate via two dedicated metabolic modules that degrade glucuronate or galacturonate (Fig. 3A, B). No Lactobacillus or Bifidobacterium strain encodes the full glucuronate degradation module, and only a few Bifidobacterium strains possess the galacturonate degradation module (Fig. S3), highlighting Gilliamella’s metabolic features in pyruvate production.

    Fig. 3: Characteristic carbohydrate utilization in Gilliamella.
    figure 3

    A Maximum-likelihood phylogeny of Gilliamella strains, annotated with the number of genes involved in carbohydrate metabolism: enzymes involved in degradation modules of glucuronate (M00061), galacturonate (M00631), and ascorbate (M00550); proteins transporting only glucose, glucose and maltose, or multiple sugars including glucose; primary hydrolases targeting polysaccharides. Circle and triangle sizes indicate gene copy number. B Schematic metabolic pathways inferred from Gilliamella and honeybee genomes. The Gilliamella-generated substrates can be potentially utilized by the host in lipogenesis. G3P glyceraldehyde 3-phosphate, LCFAs long-chain fatty acids, ELOVL6 elongation of very long chain fatty acids protein 6, ChREBP carbohydrate-responsive element binding protein, PRPP 5-phosphoribosyl diphosphate. C Gene clusters involved in polysaccharide deconstruction and further utilization generating pyruvate in the strain Gilliamella B3835. D Differential growth of Gilliamella on varied carbon sources demonstrates its preference for glucuronate, resulting in lower cell density. The Gilliamella B3835 strain was cultured in Brain Heart Infusion (BHI) broth (minus glucose) supplemented with 1, 10 or 20 mM of glucose, glucuronate, or ascorbate, respectively. Data are presented as means ± SD.

    Galacturonate is a backbone unit of pectin, where glucuronate is occasionally found as a side chain unit26,27. Gilliamella can hydrolyze refractory polysaccharides, especially pectin from pollen walls, releasing sugars as energy sources26,28. Our results unraveled prevalent gene clusters in the Gilliamella genome that contain modules responsible for polysaccharide degradation and subsequent monosaccharide transport and catabolism. For instance, in strain B3835 from A. cerana (Fig. 3C), genes for galacturonate and glucuronate degradation are located close to genes encoding pectin-degrading enzymes GH2829 and GH3130, while the transporters and catabolic enzymes for galactose are adjacent to β-D-galactofuranosidase GH43_3. Intriguingly, a pyruvate dehydrogenase complex repressor (pdhR) is encoded nearby, suggesting that downstream pyruvate catabolism can be suppressed. These enzymes are organized into carbohydrate-active enzyme gene clusters (CGCs)31, members of which are typically co-expressed32, enabling efficient stepwise conversion of polysaccharides into energy substrates.

    In addition to pectin, we found that Gilliamella can also hydrolyze β-glucan, which is another abundant polysaccharide component of the pollen coat (Fig. 3A). The backbone of hemicellulose β-glucan is glucose27, which could serve as a direct energy resource for Gilliamella. However, to utilize glucose as a routine energy supply, Gilliamella would require glucose-specific transporters, which we found surprisingly missing in their genomes. Almost all Gilliamella strains possess only one gene copy (mostly gene crr) to transport multiple sugars, including glucose (Fig. 3A, Supplementary Data 1). Alternatively, because bacteria secrete hydrolases for saccharification, Gilliamella is expected to release a considerable amount of glucose into the hindgut, which could become accessible to the host for lipogenesis33,34 and thermogenesis34,35. Complementary to their limited glucose uptake, Gilliamella strains possess numerous genes for utilizing alternative saccharides, such as galactitol, fructose, mannose, and β-glucoside (Fig. S2). Particularly, most transporter genes target ascorbate. Gilliamella encodes an intact ascorbate degradation module generating D-xylulose-5P, which is lacking in most Lactobacillus strains and all Bifidobacterium strains (Fig. 3A, B, Fig. S3). D-xylulose-5P can be converted to energy and 5-phosphoribosyl diphosphate (PRPP), a key nucleotide precursor, via the pentose phosphate pathway. Therefore, Gilliamella is capable of utilizing a diverse range of alternative saccharide substrates in the gut.

    To assess the growth performance of Gilliamella on different carbohydrate sources, we simultaneously cultured Gilliamella using a Brain Heart Infusion (BHI) broth without glucose, supplemented with glucuronate, ascorbate, or glucose (Fig. 3D). Compared to glucose and ascorbate, glucuronate-fed cultures evidently entered the log phase earlier, demonstrating a preference for glucuronate, thus validating our prediction based on genomics. Intriguingly, when supplied with equal molar amounts of carbon, glucuronate and ascorbate yielded cultures that plateaued at lower OD600 values than glucose, indicating a lower proliferation on these substrates. These decreased cell densities are expected to consume less carbon sources, potentially alleviating competition with both the host and other gut microbes. Additionally, 10 mM glucuronate or ascorbate at 10 mM supported higher growth than 20 mM, indicating that Gilliamella thrives at moderate substrate concentrations.

    Microbiome analysis corroborates Gilliamella’s strength in energy generation

    To investigate the impact of Gilliamella enrichment on gut microbiome function, we quantified the relative abundance of carbohydrate metabolic pathways and their bacterial contribution in the gut metagenomes of six Apis honeybees. Our results showed that the abundance of genes encoding transporters capable of glucose uptake was negatively correlated with Gilliamella’s abundance, but positively correlated with that of Lactobacillus and Bifidobacterium (Fig. 4A). Our genome analyses (Fig. 3A, Supplementary Data 1) showed that most Gilliamella strains lack dedicated glucose transporters (e.g., glcU, ptsG) and instead carry only crr, which transports a broad range of sugars. Consistently, our metagenomic data reveal that glcU, ptsG, and the multiple sugar transporter msmX are rarely encoded by Gilliamella (Fig. 4A), with the maltose/glucose transporter malX found in strains derived from giant honeybees and a few western honeybees. In contrast, ptsG and msmX are common in Bifidobacterium, and especially abundant in Lactobacillus from dwarf honeybees, reflecting their robust glucose-uptake capacity. Hence, our findings from bacterial strain genomes and gut metagenomics both suggest that the enrichment of Gilliamella corresponds to a reduced overall capacity for glucose uptake within the gut microbiota of cold-adapted honeybees.

    Fig. 4: Gut microbiome comparison in carbohydrate metabolism across honeybees.
    figure 4

    A The gene abundance of glucose transporters in gut metagenomes contributed by varied bacteria. The y-axis is the gene abundance of transporters capable of glucose uptake. Pearson correlation coefficient (R) and P value (p) are annotated. Gilliamella rarely encodes glucose transporters, especially glucose-specific transporters (glucU and ptsG), across all metagenome samples (upper panel). And its abundance is negatively associated with the abundance of all glucose transporters in metagenomes (lower panel). The abundance comparison of genes encoded by three gut bacteria in the (B) degradation module of glucuronate, galacturonate and ascorbate, and (C) PRPP production from D-xylulose-5P shows Gilliamella’s superior degradation capacity in alternative carbon sources whereas lower consumption of D-xylulose-5P. ns: no significant difference, **P value < 0.01, ****P value < 0.0001 by Mann–Whitney U test (B–D). Each dot denotes one gut metagenome sample. D Glucose proportions across gut tissues in four sympatric honeybees, A. cerana (Acer), A. dorsata (Ador), A. andreniformis (Aand) and A. florea (Aflo), examined by saccharide metabolomics show significantly more glucose in Acer rectums. Two-way ANOVA and Tukey test were used for the comparison. Data are presented as means ± SD.

    With regards to carbohydrate metabolism, Gilliamella allocates more genes for pentose and glucuronate interconversions than Lactobacillus and Bifidobacterium (Fig. S4a), specifically for the degradation modules of glucuronate, galacturonate, ascorbate and pectin (Fig. 4B, Fig. S4b). This leads to enhanced production of pyruvate and D-xylulose-5P. Meanwhile, Gilliamella encodes fewer genes that convert D-xylulose-5P to D-ribose-5P and the downstream PRPP (Fig. 4C, Fig. S4c).

    To test whether enriched Gilliamella in gut microbiome affects the availability of hindgut glucose for honeybee hosts, we applied saccharide metabolomics across the gastrointestinal tract of various honeybee species (Fig. 4D, Supplementary Data 2). In particular, four sympatric honeybees were included to alleviate the potential bias of sugar ingestion derived from diverged floral diversity. Among these, workers of three tropical honeybees, A. dorsata, A. florea and A. andreniformis, and the cold-adapted A. cerana, were collected in their natural range of close geographic proximity in Jinuo Co., Yunnan Province, China (Fig. S1a). The diets of the four honeybee species showed no significant variations in glucose proportion, as demonstrated in beebread and honey samples retrieved from their colonies (Fig. S5a, Supplementary Data 2). The glucose content also showed a similar level in both the midguts and ileums among honeybees, but was significantly elevated in the rectum of A. cerana (Fig. 4D). But, no evident difference was found between cold-adapted A. cerana and three tropical honeybees for other mono- or disaccharides (Fig. S5b). Therefore, these results suggest that the enrichment of Gilliamella is associated with enhanced glucose availability in the hindgut.

    Gilliamella colonization assays confirm promotion of hindgut glucose and pyruvate access

    To further verify the influence of Gilliamella on hindgut glucose content, monocolonization was performed and compared to germ-free bees. Glucose content in the hindguts of Gilliamella-colonized bees is significantly higher at both 48 h and 7 days after inoculation (Fig. 5A). Host glucose absorption typically occurs in the midgut via a concentration-dependent process, where glycogen synthesized in gut epithelium cells creates concentration gradients, thus facilitating glucose uptake36,37. However, little is understood about glucose absorption in the hindgut. We examined the ileum and rectum and found a considerable amount of glycogen in epithelial cells stained purple, as in the midgut (Fig. 5B), indicating potential for glucose absorption. Gilliamella inoculation up-regulated genes for glucose and pyruvate transport and catabolism (Fig. 5C), as well as pathways in carbohydrate metabolism (e.g., the tricarboxylic acid cycle) and lipid synthesis (Fig. S6a, Supplementary Data 1). Hence, based on evidence from both cell morphology and gene expression, we infer that honeybee hosts can utilize glucose and pyruvate generated by Gilliamella in the hindgut. We further found that the genes involved in the synthesis and secretion of glucuronate are also up-regulated (Fig. 5C, Supplementary Data 1) in the Gilliamella-colonized group. These data suggest the host may secrete glucuronate to fuel Gilliamella, since the bacterium prefers the glucuronate degradation pathway to produce pyruvate. In turn, this cross-feeding would benefit the host by providing additional pyruvate.

    Fig. 5: Honeybee-Gilliamella coadaptation to coldness via enhanced lipid synthesis.
    figure 5

    A Glucose contents in A. mellifera hindguts colonized by Gilliamella (Gc) versus germ-free ones (GF), showing significant glucose increase following bacterial inoculation. B The glycogen synthesized in gut cells was stained purple using Periodic-Acid Schiff (PAS) staining, suggesting that the hindgut can absorb glucose like the midgut. C The up-regulated genes in Gc versus GF indicate potential cross-feeding between the host and Gilliamella. D Enzymes involved in glucose, pyruvate, lipid, and glucuronate productions contain more gene copies in cold-adapted honeybees. E Maximum-likelihood tree based on the ELOVL6 gene sequences with motifs annotated, suggesting historical gene duplication in cold-adapted honeybees and bumblebees. F Gilliamella inoculation resulted in significantly elevated abdominal triacylglycerol (TAG) on day 10 post-inoculation. G Histological comparison shows Gilliamella colonization affects host lipid storage. HE (hematoxylin and eosin), PAS, and ORO (Oil Red O) were used for cell, glycogen, and lipid staining, respectively. Black arrows indicate multilocular lipid droplets in Gc bees; red arrows indicate unilocular droplets in GF bees. H Hindgut ascorbate is significantly increased in A. mellifera and A. cerana 48 h after Gilliamella inoculation.

    Honeybee genomes and colonization assay reveal host-symbiont coadaptation via lipogenesis

    To explore potential mutualistic cross-feeding between host and symbiont and their synergy toward thermogenesis, we inspected the featured genomic contents of the cold-adapted honeybees, with a focus on functions involved in fuel synthesis for thermogenesis, including glucuronate, pyruvate, glucose, and lipid. The comparative genomic analyses (Fig. 5D, Supplementary Data 1) included genomes of six honeybees and two bumblebees that are also adapted to temperate climates. We found that A. mellifera and A. cerana generally possess more genes for synthesizing glucose, pyruvate, and lipids than their tropical relatives, albeit they differ in details. For example, A. mellifera possesses more genes for transporting trehalose, which can be hydrolyzed into two glucose molecules, while A. cerana has more genes for degrading maltose and sucrose into glucose. Similarly, A. mellifera possesses more genes for converting UDP-galactose to UDP-glucose, while A. cerana has more genes for converting serine and lactate to pyruvate. Notably, cold-adapted bees generally encode more copies of the long-chain fatty acid elongation protein ELOVL6 (K10203), a key protein involved in lipid synthesis, as seen with potential historical gene duplication in both A. mellifera and A. cerana, and the bumblebee B. terrestris (Fig. 5D, E). Different from those in the bumblebee, ELOVL6 homologs remain relatively conservative across all six honeybee species, with one identical homolog shared by all, and the other two vary at the sequence level but identical motifs (with one exception of a shortened protein in A. mellifera) (Fig. 5E). One of the derived ELOVL6 homologs was only shared between A. mellifera and A. cerana, showing small but consistent sequence differences between species. In contrast, no relevant protein showed higher gene copy numbers in the genomes of tropical honeybees when compared with cold-adapted honeybees. In mammals, glucose and pyruvate are required to synthesize lipids33, and these three energy substances mediate thermogenesis35,38,39. We hypothesize that honeybees and Gilliamella co-work to facilitate cold-tolerance through improving host lipogenesis.

    Triacylglycerol (TAG) stored in the fat body was measured to test the impact of Gilliamella colonization on host lipogenesis. Gilliamella-colonized bees demonstrated significantly higher TAG accumulation than the germ-free hosts (Fig. 5F). Gilliamella colonization also resulted in increased fat body cells (Fig. S6b), forming a cell layer surrounding the inner side of the abdomen’s exoskeleton. On the contrary, only a few fat body cells were sporadically observed throughout the entire section of the germ-free abdomen. The presence of lipid droplets was confirmed using oil red O staining (Fig. 5G). In mammals, the white adipose tissue (WAT) stores fat as unilocular lipid droplets, while the brown adipose tissue (BAT) harbors multilocular lipid droplets characterized by highly condensed mitochondria for efficient thermogenesis25. Intriguingly, we observed multilocular lipid droplets in the Gilliamella-colonized bees resembling mammalian brown adipose tissue BAT, and unilocular lipid droplets similar to mammalian WAT in the germ-free bees. In addition, the fat cell nuclei of the Gilliamella-colonized bees were distorted and pressed by fat globules (Fig. 5G), indicating extensive fat accumulation40. Furthermore, the Gilliamella-colonized bees also contain more glycogen than the germ-free bees (Fig. 5G).

    Honeybees provide ascorbate when Gilliamella is inoculated

    Like the two bumblebees, A. mellifera, A. cerana and A. dorsata have more glucuronosyltransferase genes (K00699, Fig. 5D) than other honeybees. Glucuronosyltransferase, shared by the glucuronate pathway and the ascorbate biosynthesis module, catalyzes glucuronate generation (Fig. 5D). Intriguingly, the accumulation of glucuronate is toxic to the honeybees41. Thus, its downstream transformation into ascorbate or D-xylulose-5P is necessary. Because it is difficult to distinguish glucuronate from galacturonate using regular gas chromatography-mass spectrometry gut metabolomics42, the significantly increased galacturonate reported previously in Gilliamella colonized guts43 might have included the glucuronate produced by the honeybee host. Thus, we alternatively detected its downstream metabolite ascorbate. We found that the hindgut ascorbate content is significantly higher in the Gilliamella-colonized bees than in the germ-free bees (Fig. 5H).

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