It makes me want to clean the fingerprints.
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Famous oddball quasar isn’t X-ray weak after all, astronomers say
For more than two decades, the quasar PHL 1811 has been considered the prototype of a rare class of “intrinsically X-ray weak” quasars, thought to produce unusually little X-ray radiation. But in 2024, the Einstein Probe spacecraft caught the object in a bright X-ray flare. In a new study, astronomers combined that observation with more than 20 years of archival data to revisit the mystery. The findings were published in The Astrophysical Journal on July 28.
In active galactic nuclei (AGN), material spiraling into the central black hole releases enormous amounts of energy. The accretion disk—the swirling ring of hot gas around the black hole—releases this energy primarily in optical and ultraviolet (UV) light. Additionally, a separate region of extremely hot plasma, called the corona, sits above the disk and is responsible for the X-ray emission. The link between these two emissions is well established.
A rare subset of AGNs breaks this pattern, appearing far dimmer in X-rays than expected, often linked to black holes feeding faster than the theoretical limit. This could mean either that gas is blocking the X-rays without dimming the optical/UV, or that it is “intrinsically weak” as the X-ray-emitting corona itself is genuinely suppressed.
Recyclable glue bonds underwater in seconds and holds for years
Most glues need a dry surface to stick properly. Bonding materials underwater is challenging because water forms a thin film on any surface, so instead of an adhesive touching a material directly, it touches a layer of water, which weakens the bond. But scientists from China have now created a superglue that repels water and forms a strong, recyclable bond within seconds, as they report in a paper published in Nature Communications.
To make their glue, the research team synthesized a supramolecular ionic liquid, a salt-like material whose molecules are held together by temporary, reversible interactions. They mixed it with a solvent called dimethyl sulfoxide (DMSO) and applied the solution directly onto submerged objects made of ceramic, copper, epoxy resin and polyamide.
When the mixture hits the underwater surface, differences in surface tension trigger a rapid motion called Marangoni flow that disrupts the thin layer of water on the surface. The DMSO solvent then diffuses outward, causing the molecules to reassemble into a tough, water-resistant adhesive within seconds.
Long-sought Zhang-Rice singlet visualized directly in cuprate superconductor
Superconductors are materials that conduct electricity with zero electrical resistance below specific temperatures. Most of these materials become superconducting at very low temperatures, but some also exhibit superconductivity at higher temperatures.
Superconductors have proved advantageous for the development of numerous technologies, ranging from medical imaging instruments to particle accelerators, nuclear reactors, power transmission lines and quantum computers. While past studies have shed light on the physical underpinnings of conventional, low-temperature superconductivity, the processes contributing to high-temperature superconductivity remain poorly understood.
Researchers at Tsinghua University and the Chinese Academy of Sciences recently carried out a study aimed at better understanding the physical processes that give rise to superconductivity in hole-doped Ca₂CuO₂Cl₂ (CCOC), an unconventional cuprate superconductor.
Single synthetic peptide forms electrically polarized, self-healing hydrogel
Researchers from the RIKEN Center for Sustainable Resource Science (CSRS) and RIKEN Pioneering Research Institute (PRI) in Japan, together with collaborators from the University of Münster, Germany, have developed a new hydrogel that offers significant advantages over others currently on the market in the field of biomaterials.
Based on a single synthetic peptide called FQ(Pyr), the new hydrogel has a highly organized structure made of nanofibers containing tiny water channels. The molecules within each nanofiber all point in the same direction, creating electrical polarization along the fiber. This means that, in addition to being strong and flexible, the new gel could be used to transport ions, generate electrical signals when squeezed or have other advanced interactions with biological tissues.
The findings were published in Nature Communications.
Genetic switch could help tomatoes produce fruit in cold weather
Every tomato begins with a flower. But before a fruit can grow, an intricate sequence of events must happen in perfect order. The flower’s male and female organs must develop together, pollen must be released at exactly the right time, and fertilization must occur.
Many things can disrupt this delicate process, including genetic changes and environmental stress. Temperature extremes are a major challenge: Cold can reduce pollen viability and prevent fertilization, while previous research has shown that heat can also interfere with fruit set.
Now, researchers have uncovered a genetic system that keeps this process synchronized. Their findings could eventually help scientists develop tomato varieties that produce fruit more reliably during challenging growing conditions, including colder seasons.
Hybrid bioprinter creates capillary networks narrower than 10 micrometers
More than 100,000 people are awaiting an organ transplant in the United States, with a new candidate added to the list every 10 minutes. Even if the transplant is carried out successfully, recipients must take immunosuppressive medications, elevating their risk of broader infections, and adhere to a strict lifestyle for the rest of their lives—all while facing the possibility that their body could reject the donated organ at any time.
Scientists have been aiming to bioprint tissues and organs from a patient’s own cells for decades in an attempt to solve this problem. But a major obstacle to realizing lab-grown organs is replicating the scale and complexity of the body’s vascular networks, especially capillaries. These microvessels crisscross each organ to deliver oxygen and other nutrients to every living cell, making them an essential component of any useful bioengineered tissue model.
Spontaneous magnons synchronize with external signals at room temperature
Signals ride on waves of one kind or another: light, sound, radio. But new carriers are needed to relay information in next-generation devices. Disturbances or waves in magnetic materials called magnons could be an efficient option—if scientists can tame them.
A team led by researchers from the U.S. Department of Energy’s (DOE) Argonne National Laboratory and the University of Illinois Urbana-Champaign (U. of I.) has developed a method to generate spontaneous magnons in a material called yttrium iron garnet (YIG) that can be tuned to an external signal.
The results, reported in Nature Communications, establish a pathway toward controllable magnons that are relevant for next-generation microelectronics, wireless communication and quantum information processing.
Quantum advantage reassessed: More realistic benchmarks for quantum algorithms
Quantum advantage refers to the point at which a quantum computer solves a clearly defined task faster or more efficiently than any classical computer—or makes it solvable in the first place. For many practical applications, this has not yet been demonstrated. Research therefore relies heavily on theoretical models and simulations to explore where and under what conditions such an advantage may realistically be achieved in the future.
Quantum simulation is considered a promising path toward genuine quantum advantage.
However, many existing approaches in quantum chemistry rely on simplifying assumptions: They describe molecules as closed systems perfectly isolated from their environment, model only unitary dynamics and focus on calculating ground states within the Born-Oppenheimer approximation. In nature, none of these assumptions fully hold.