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Dormant black hole revives in under three years, brightening 10-fold in nearby galaxy

Astronomers monitoring a nearby active galaxy for six years have watched its supermassive black hole dramatically wake up, brightening by a factor of 10 across ultraviolet and X-ray wavelengths. The paper outlining the study was posted to the preprint server arXiv on May 18.

In active galactic nuclei (AGN), material spiraling into the central black hole releases enormous amounts of energy. The accretion disk—a swirling ring of hot gas—radiates this energy primarily in optical and ultraviolet (UV) light. Additionally, a separate region of extremely hot plasma sits above the disk. It is called the corona, which is responsible for the X-ray emission.

Understanding how these two components relate to each other and how they evolve as a black hole’s feeding rate changes remains an open problem.

Molecular glasses solve long-standing Arrhenius paradox

Glasses are non-crystalline but solid states of matter in which molecules and atoms are not arranged into a regular crystal lattice, but rather in a disordered pattern. Glassy materials are widely used in various settings, for instance, in the synthesis of pharmaceuticals and the development of electronics or optical devices.

When studying movement and changes in various materials and substances, physicists commonly rely on the so-called Arrhenius model. This is a mathematical framework introduced by Svante Arrhenius in 1889, which can be used to calculate how temperature affects the speed of a heat-activated chemical reaction or physical process.

Past studies have shown that when the Arrhenius model is applied to molecular glasses, it yields unrealistically small pre-exponential factors. Pre-exponential factors are values that describe the intrinsic timescale of the movement of molecules without considering temperature effects.

Proteins can be selectively controlled with radio waves

In a significant advance in biological quantum sensing, a research team led by the Technical University of Munich (TUM) has discovered and tested a new mechanism of action in which proteins can be controlled with radio waves. In doing so, they influence a sensitive quantum state known as spin and make it visible via light. In the future, such findings could help detect and even direct biochemical processes in cells simply from the outside using radio waves.

Until now, quantum sensing has primarily been known from solid-state materials such as diamonds with deliberately introduced tiny defects. The researchers are now transferring this principle to proteins —biological molecules that can be genetically produced and specifically tailored. In the future, this could allow quantum sensors to be built directly into cells or tissue.

These protein-based sensors are potentially particularly well suited for biosensing—that is, for imaging living cells, tissues, or organs. In theory, they sit directly where measurement is needed, making them suitable for studies in organisms—unlike bulky solid-state sensors.

100kW fully superconducting aviation motor developed for electrical aircraft

Researchers at a Scottish university have demonstrated a 100kW fully superconducting aviation motor that could help pave the way for an electric aircraft.

The prototype system, created by the Applied Superconductivity Laboratory (ASL) at the University of Strathclyde in Glasgow, represents one of the first attempts in the world to develop a fully superconducting axial-flux motor for aviation.

The motor uses high temperature superconducting (HTS) technology to carry very large electrical currents with almost no resistance when cooled to cryogenic temperatures: 20 Kelvin (K) or −253 °C.

First human SMUG1 atomic snapshots reveal how cells repair DNA

Researchers have captured the first atomic structures of human SMUG1, an enzyme that helps cells repair damaged DNA. The findings provide new insight into how cells recognize and remove harmful DNA bases, and may support future efforts to develop drugs that target this DNA repair pathway.

“These structures give us the first detailed view of how human SMUG1 engages damaged DNA and carries out the first steps of repair,” says professor Pål Stenmark, who led the study.

DNA is constantly damaged by normal processes in our cells, as well as by environmental factors and cancer treatments. If the damage is not repaired, it can lead to permanent mutations.

Deep brain stimulation boosts myelination and shifts brain networks linked to depression

Researchers from the Icahn School of Medicine at Mount Sinai have uncovered the first direct evidence that deep brain stimulation (DBS) can remodel white matter pathways in the brain and alter communication across large-scale neural networks, revealing a previously unrecognized mechanism that may explain how the therapy helps patients recover from severe depression. The study, published June 1 in Nature Neuroscience, provides critical insight into the biological basis of DBS, an emerging therapy for treatment-resistant depression and other neuropsychiatric disorders.

Deep brain stimulation, approved by the U.S. Food and Drug Administration to treat essential tremor, Parkinson’s disease, epilepsy, and obsessive-compulsive disorder, is a neurosurgical procedure involving placement of a neurostimulator (sometimes referred to as a “brain pacemaker”), which sends high-frequency electrical impulses through implanted electrodes deep in the brain to specific areas responsible for the symptoms of each disorder.

Although DBS has shown sustained clinical benefit for many patients with severe depression who do not respond to medications, psychotherapy, and electroconvulsive therapy, the mechanisms underlying its therapeutic effects have remained poorly understood.

Atomic reshuffle leads to record-breaking catalysts for hydrogen production

Researchers have discovered that atoms can be mixed, separated, and recombined within the same experiment, providing a pathway to a record-breaking catalyst for green hydrogen production. In their study, the team created nanoscale particles containing only a few dozen platinum and nickel atoms and observed unusual dynamic behavior in direct space and in real time. As the two metals separate from one another while maintaining an interface, they become highly active for electrochemical water splitting, leading to efficient hydrogen evolution.

The project was led by the University of Nottingham in collaboration with the University of Birmingham, Diamond Light Source, and Ulm University in Germany. The study appears in Advanced Materials.

Research team leader Dr. Jesum Alves Fernandes, from the School of Chemistry, University of Nottingham, said, “What makes this discovery exciting is that we can reversibly tune the structure of the particle while directly observing the process at the atomic scale. This opens a new strategy for designing adaptive catalysts for a wide range of applications.”

A new origin story for multicellular life points to physics, not genes alone

How did life make the leap from single cells to coordinated, multicellular organisms? And how do genetically identical cells still perform a version of that feat every time an embryo begins to take shape?

In a new Perspective paper appearing in the journal Nature Biotechnology, Bren Professor of Biology and Biological Engineering Magdalena Zernicka-Goetz and collaborator Qi Chen of the University of Utah ask one of biology’s oldest questions in a new way. The paper is titled “Decoding the origins of cellular self-organization for engineered biology.”

Violent rocket particles could reshape future spacecraft design

When rockets fire into space, the insides of their engines become an extreme environment where temperatures soar and tiny particles are thrown around at hypersonic speeds. These particles behave in ways that break long-held assumptions, according to new research that could help improve the durability, safety and performance of future space and defense technologies.

The study shows that particles traveling at hypersonic speeds do not remain spherical, instead melting and deforming mid-flight in ways that change how heat, drag and energy move through rocket systems. The findings, published in Physics of Fluids, have led researchers to develop a new drag model that more accurately predicts particle behavior under extreme conditions.

The work was led by researchers from the Southeast University–Monash University Joint Research Institute, Monash University and Shanghai University.

Predicting physics without parameter tuning: A faster computational approach

Numerical simulations in physics often require estimating a multitude of parameters, making the process computationally expensive and complex. Researchers at University of Tsukuba have introduced a new method called the multiparameter eigenvalue-problem emulator, enabling reliable predictions based directly on relationships among known data by eliminating the need for parameter estimation. This innovation considerably reduces computational costs and enables systematic quantification of predictive uncertainty.

Calibrating theoretical models with experimental data is a common practice in physics for predicting previously unobserved phenomena. However, real-world theoretical models are often highly complex, involving numerous numerical quantities, known as parameters, that cannot be directly measured. Researchers must estimate these parameters to compute other observables. This is a process that is computationally demanding and fraught with remarkable challenges in assessing how uncertainties in the parameters affect final predictions.

This study, published in Physical Review Letters, presents a novel fast surrogate model based on a mathematical framework known as the multiparameter eigenvalue-problem emulator. This model directly predicts unknown observables based on relationships among known data, without the need to introduce or estimate parameters.

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