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Artificial kinetochores take the pressure off aging chromosomes during meiosis

For sexual reproduction to yield healthy offspring, newly generated oocytes—immature egg cells—must receive the correct amount of DNA after cell division. This process of segregating chromosomes becomes more prone to failure as we age. Now, RIKEN researchers have identified a strategy that could help to prevent such errors and restore healthy production of oocytes.

Oocytes are produced by a cell-division process known as meiosis, during which every chromosome is duplicated. These replicates form X-shaped structures in which the chromosomes are joined via structures called centromeres, where a protein called cohesin locks chromosome copies together.

As division proceeds, protein fibers called microtubules spread from opposite poles of the dividing cell, attaching to each chromosome. These microtubules eventually pull the two apart, so that each newly formed cell receives one copy of each chromosome.

Photonic ‘ski jumps’ efficiently beam light into free space

Photonic chips use light to process data instead of electricity, enabling faster communication speeds and greater bandwidth. Most of that light typically stays on the chip, trapped in optical wires, and is difficult to transmit to the outside world in an efficient manner.

If a lot of light could be rapidly and precisely beamed off the chip, free from the confines of the wiring, it could open the door to higher-resolution displays, smaller Lidar systems, more precise 3D printers, or larger-scale quantum computers.

Now, researchers from MIT and elsewhere have developed a new class of photonic devices that enable the precise broadcasting of light from the chip into free space in a scalable way.

Acoustic driving enables controlled condensation of light and matter on chip

An international research team led by Alexander Kuznetsov at the Paul Drude Institute for Solid State Electronics (PDI) in Berlin has demonstrated a fundamentally new way to control the condensation of hybrid light-matter particles. Using coherent acoustic driving to dynamically reshape the energy landscape of a semiconductor microcavity, the researchers achieved deterministic steering of a macroscopic quantum state into its lowest energy configuration.

The results, published in Nature Photonics, establish a strategy for engineering nonequilibrium quantum states and open prospects for ultrafast, tunable photonic technologies.

In collaboration with long-term partners from the National Scientific and Technical Research Council CONICET and the Bariloche Atomic Center and Balseiro Institute in Argentina, the team experimentally realized a universal scheme for selectively transferring populations within a multilevel quantum system using strong time periodic modulation.

Fiber setup compresses mid-infrared pulses to 187 femtoseconds using just 80 watts

Ultrashort mid-infrared (mid-IR) laser pulses are essential for applications such as molecular spectroscopy, nonlinear microscopy, and biomedical imaging, but their generation often relies on complex and power-intensive systems that are difficult to implement outside of specialized laboratories. These systems usually require high pump powers, elaborate optical setups, and precise alignment, which can limit their widespread adoption and practical use in everyday research and clinical settings.

In a paper published in the IEEE Journal of Quantum Electronics, a team of researchers from SASTRA Deemed University, Thanjavur, report a compact, fiber-based method for generating clean ultrashort mid-IR pulses at significantly reduced input power.

The study demonstrates that high-quality pulse compression can be achieved using a holmium-doped ZBLAN photonic crystal fiber integrated into a nonlinear optical loop mirror (NOLM), offering a simpler and more energy-efficient alternative to conventional systems.

Researchers mix X-rays and optical light to track speedy electrons in materials

To unlock materials of the future, including better photocatalysts or light-switchable superconductors, researchers need to understand how the valence electrons within materials respond to light at the atomic scale. Materials are made of atoms, and an atom’s outer electrons, or valence electrons, are responsible for chemical bonding as well as a material’s thermal, magnetic, and electronic properties.

But imaging valence electrons in bulk materials is extremely difficult because valence electrons are only a small subset of a typically large pool of electrons.

Now, researchers at the Department of Energy’s SLAC National Accelerator Laboratory have refined a way to track valence electrons using a unique method that shines both X-rays and lasers onto a material, then tracks the frequency generated by both sources. The method allows the researchers to understand more about extremely fast-moving valence electrons, including the symmetry of their local environment.

Stacked quantum materials enable precise spin control without external magnetic fields

Spintronics—a technology that harnesses the electron’s magnetic quantum states to carry information—could pave the way for a new generation of ultra-energy-efficient electronics. Yet a major challenge has been the ability to control these delicate quantum properties with sufficient precision for practical applications. By combining different quantum materials, researchers at Chalmers University of Technology have now taken a decisive step forward, achieving unprecedented control over spin phenomena. The advance opens the door to next-generation low-power data processing and memory technologies.

Data centers, cloud services, AI and connected systems account for a rapidly growing share of global energy consumption. In the quest for new, more energy-efficient technological solutions, spin electronics, or spintronics, has proven to be a new and promising approach. Instead of relying solely on the movement of electric charge, spintronics use magnetic states to carry information. More specifically, it takes advantage of a quantum property of electrons known as spin, which makes electrons behave like tiny magnets.

“Just like a compass needle, an electron’s spin can point in one of two directions—up or down. These two directions can be used to represent digital information, in the same way today’s electronics use 0s and 1s,” explains Saroj Dash, Professor of Quantum Device Physics at Chalmers University of Technology.

Simulations suggest a breakthrough in understanding how turbulence develops

A new study revisits a century-old question about how turbulence starts. The findings could potentially influence not only aircraft engineering but even the design of mechanical heart valves, and treatment of heart disease. The study is published in Scientific Reports.

Computer simulations at Stockholm’s KTH Royal Institute of Technology indicate that very small vortices may create increasingly larger swirls of flow—the opposite of the traditional view of how energy is transferred in turbulence.

Often seen in nature, from whirlpools to the shape of galaxies, vortices are one of the main flow structures that drive turbulence. The dominant idea over the last 100 years is that large swirling motions in a fluid break apart into smaller and smaller swirls, passing energy down the chain until it finally disappears—a process known as the forward cascade.

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