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Age does not appear to drive cardiovascular risk in pregnancy

Underlying cardiovascular risk, rather than older age, drives complications such as venous thromboembolism, cardiomyopathy and heart failure during pregnancy, according to new Weill Cornell Medicine research. The findings may encourage doctors to more actively address cardiovascular health in patients before they become pregnant.

The study, published in Nature Communications, suggests that instead of pregnancy becoming inherently riskier as people get older, it amplifies a person’s baseline cardiovascular risk, regardless of age.

“Pregnancy seems to be a uniform stress test, so to speak,” said the study’s lead author, Dr. Hooman Kamel, vice chair of clinical research and chief of neurocritical care in the Department of Neurology and the Helen and Albert Moon Professor of Neurology at Weill Cornell Medicine.

Gleaning Information from Noise

Researchers derive a universal limit linking noise and response to perturbations in systems far from equilibrium.

Noise comes in many forms. A microscopic bead twitches in an optical trap; voltage fluctuations flicker through a circuit. But it’s not only a nuisance. Since 1966, physicists have understood that for systems in thermal equilibrium, such randomness also gives valuable information: Spontaneous fluctuations and the system’s response to external perturbations are locked together, frequency by frequency, according to the so-called fluctuation–dissipation theorem (FDT) [1]. That link is the basis of noise-based thermometry, microrheology, and many calibration methods. But thermal equilibrium is rare in the real world. Rather, most physical and biological systems are driven by an external force, fed, or alive, with energy continually flowing through them.

Ultrafast switching device unlocks low-power optical-to-electrical conversion for AI hardware

Modern energy demands are soaring as technologies like AI and IoT become more common, and researchers have been working hard to develop hardware that can keep up. Now, a team of researchers from the University of Tokyo has developed an ultrafast and energy-efficient nonvolatile switching device, described in an article published in the journal Science, that may soon be able to significantly reduce power consumption for high-energy demand technologies.

Currently, most nonvolatile switching devices for data processing architectures have operating speeds in the nanosecond range. However, faster speeds are required for modern central processing units (CPUs), which operate in the gigahertz range.

At 5 GHz, a single cycle lasts only 200 picoseconds. If a switching device takes a nanosecond (1,000 picoseconds) to turn on or off, it misses multiple clock cycles, creating a major bottleneck that prevents the processor from operating continuously at full capacity. Optical interconnects are being explored to overcome electronic bottlenecks, but more efficient optical-to-electrical (O/E) conversion is still needed.

A new way to recharge aging muscle stem cells by restoring a key metabolic component

Losing muscle strength is a natural part of aging. At the core of this decline is a drop in the number of muscle stem cells (MuSCs), the specialized cells responsible for maintaining and regenerating muscle tissue throughout our lives. Loss of muscle strength can severely affect mobility, increasing the risk of falls, fractures and, most importantly, the loss of independence.

Published in Nature Aging, a recent study took a crucial first step toward restoring stem cell function in aging muscles—gaining a clearer understanding of how metabolism changes when stem cells are activated and how these critical processes weaken with age.

The researchers’ investigation led them to glutamine metabolism, the process by which cells use the amino acid glutamine to support essential functions. They found that for MuSCs, glutamine is more than just a nutrient. It provides the raw material needed to produce fatty acids that help cells grow, divide, and repair damaged muscles.

Written in the eye: How the retina’s biological age could help predict osteoporosis risk

Eyes, the high-resolution biological devices that help us visualize the outside world, are now being used as a portal to assess our internal health. Scientists have found that a closer evaluation of how one’s retina is aging can provide crucial hints about bone health, especially in conditions such as osteoporosis, which makes bones weaker and more prone to fractures.

A recent study conducted in Singapore and the UK collected over 45,000 retinal images and used an artificial intelligence (AI) tool called RetiAGE to estimate a person’s retinal biological age. When researchers compared retinal age with bone mineral density, they found an inverse relationship between the two.

Among participants in Singapore, people with older-looking retinas tended to have lower bone mineral density and higher fracture risk scores. Meanwhile, the UK-based cohort, where participants were studied for over a decade, revealed that a higher retinal biological age at the start of the study was a predictor for a greater chance of developing osteoporosis by the end of it.

Twisted WSe₂ reveals elusive charge-neutral quantum modes

Quantum materials, materials with properties that are influenced by the laws of quantum mechanics, have attracted considerable attention over the past few decades. Their unique properties make these materials advantageous for the development of numerous cutting-edge technologies, including quantum computers, highly sensitive sensors and energy-efficient electronics.

In some quantum materials, electrons strongly interact with each other, producing what are known as correlated quantum phases, states in which the behavior of individual electrons is influenced by the behavior of other electrons. These phases can give rise to desirable properties or effects, including superconductivity, magnetism and collective excitations.

Researchers at University at California at Santa Barbara recently observed charge-neutral propagating collective spin-valley modes, coordinated waves of quantum behavior that carry no electrical charge and are difficult to probe experimentally, in the two-dimensional (2D) semiconductor twisted tungsten diselenide (WSe2).

Bioengineers condense protein engineering and testing to a single day

Proteins are critical to life—and to industry. There are countless proteins that could be engineered to treat and even cure serious diseases and cellular dysfunctions. Industrial applications are similarly promising, with proteins increasingly used as enzymes in food manufacturing and in consumer detergents.

While AI can help suggest improvements, each novel protein must still be created in the real world and tested for performance. It is a labor-intensive process that involves constructing the DNA instructions for each protein in yeast or bacteria and growing individual clones for protein production and testing. This can take many days for a single protein of interest and even longer if the protein needs to be tested in mammalian cells, a process that requires retrieving DNA from microbes for transfer to the mammalian cells.

In a new paper, Michael Z. Lin, a professor of neurobiology and of bioengineering in the schools of Engineering and Medicine, and graduate students, Yan Wu in bioengineering and Pengli Wang in chemical engineering, say they have condensed the time-intensive protein building and testing process to just 24 hours.

Dark lunar craters could host ultrastable lasers for moon navigation

They rank among the darkest and coldest places in the solar system: Hundreds of lunar craters, many of them at the moon’s south pole, never receive direct sunlight and lie in permanent shadow. That’s exactly why physicist Jun Ye and his colleagues suggest that these craters are the perfect place to build a critical component for an ultrastable laser.

On the moon, a highly stable laser—a source of coherent light that has a nearly unwavering frequency, or color—could provide a master time signal and offer GPS-like lunar navigation, said Ye, who is affiliated with both the National Institute of Standards and Technology (NIST) and JILA, a joint institute of NIST and the University of Colorado Boulder. Multiple copies of these lunar lasers could precisely measure the distances between objects and potentially detect exotic physics phenomena such as ripples in spacetime.

To construct a lunar laser, astronauts would first install a key component known as an optical silicon cavity —a block of silicon that permits only certain frequencies of light to bounce back and forth between mirrors on each end of the block. The distance between the two mirrors determines the frequencies that are allowed to resonate; for a highly stable optical cavity, that distance, and therefore those frequencies, does not vary.

Learning physics can derail some students: New research shows the best way to keep them on track

For many undergraduate students, exploring the complexities of physics for the first time, from wading through advanced mathematics, to absorbing information in a large lecture format, can be a daunting endeavor—one that dissuades many students from continuing their studies.

Educators have known for some time that students tend to learn these subjects better in hands-on, or “active learning,” environments—but some are more effective than others.

Reconfigurable Ge-Si photodetector achieves ultrahigh-speed data transmission using low-loss packaging

The rapid growth of large language models is placing increasing demands on data centers, where large volumes of data must be transferred efficiently between servers. Optical interconnects are essential for enabling this communication, but as data rates continue to rise, these systems must deliver higher bandwidth while maintaining low latency and energy efficiency. However, integrating electronic and photonic components remains challenging, as conventional approaches often introduce signal loss, limit interconnect density, and restrict scalability.

As reported in Advanced Photonics Nexus, Dr. Wei Chu and colleagues have developed a reconfigurable germanium–silicon photodetector using a low-loss integration strategy based on fan-out wafer-level packaging (FOWLP). This approach enables seamless integration of electronic integrated circuits and photonic integrated circuits on a single platform without the need for traditional wire bonding, reducing parasitic loss and improving signal integrity.

The system uses a dense network of fine metal interconnects, known as a redistribution layer (RDL), to connect components with high precision. This structure supports high interconnect density—exceeding 102 connections per square millimeter—while maintaining a low insertion loss of less than 0.3 dB/mm at 100 GHz. In addition, the use of benzocyclobutene as a low-dielectric insulating material reduces transmission loss and improves thermal stability for reliable high-frequency operation.

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