Physics is considered a cold, hard science – but it will transform your life if you view it with a bit more subjectivity, says Karmela Padavic-Callaghan
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Gut microbes unlock hormone signaling that regulates gut movement, study suggests
Millions of people worldwide are periodically or chronically affected by gut-related conditions, such as irritable bowel syndrome (IBS), gastroesophageal reflux disease (GERD) and gastroenteritis. Uncovering the physiological and biological processes that contribute to gut health could thus be highly valuable, as it might help devise more effective interventions to prevent and treat these ailments.
The transit of food, fluids and waste through the intestine is known to be coordinated by various interacting systems in the body, including gut wall muscles, neurons in the gastrointestinal tract and hormones. A growing body of research has also been exploring the crucial contribution of bacteria and other microorganisms residing in the digestive tract, which are collectively referred to as the gut microbiome.
Researchers at Boston Children’s Hospital, Harvard Medical School, the University of North Carolina at Chapel Hill and Laval University recently carried out a study aimed at better understanding how these gut microbes interact with specific sex hormones and nerve cells that control the movement of muscles in the intestines.
How a shape-shifting tiny rover inspired by Japanese toys autonomously explored the moon
Moon missions come in all shapes and sizes, from car-sized rovers packed with scientific equipment to towering rocket payloads—and now, a small, shape-shifting machine that is about the size of the average palm.
When the Japanese Smart Lander for Investigating Moon (SLIM) touched down on the lunar surface in 2024, a small rover called LEV-2 (nicknamed SORA-Q) rolled out and explored autonomously for nearly two hours. And now, with the publication of a paper in the journal Science Robotics, we are discovering just how this tiny machine navigated the terrain, made its own decisions and what it found.
The advantages of tiny rovers for space exploration include relatively low development costs, lightweight design and the ability to fit into a crowded spacecraft. But building tiny comes with many challenges.
Electron matter waves gain ultrafast torque that flips handedness in femtoseconds
Many natural processes, ranging from magnetism to chemical reactions, entail the movement and rotation of particles at very small scales. In quantum mechanics, particles exhibit both particle-like and wave-like behaviors, and their states can be described mathematically using representations known as wavefunctions.
The reliable manipulation of wave-like properties of particles as small as atoms or single electrons could open new possibilities both for studying matter and for engineering materials with desirable characteristics. Notably, controlling the angular momentum, which is the quantum property related to rotational motion, of ultrasmall particles at ultrafast timescales has so far proved very challenging when only using conventional, laser-based approaches.
Researchers at Universität Konstanz recently devised a new approach to create electron beams with an ultrafast internal torque (i.e., twisting motion). Their proposed strategy, outlined in a paper published in Nature Physics, could be a promising tool for exploring material dynamics and quantum phenomena at atomic and subatomic scales.
How bacteria use acetyl coenzyme as a building block in the formation of cells
Researchers at the University of Greifswald have discovered a new mechanism by which bacteria such as Bacillus subtilis can regulate the production of the central metabolic molecule acetyl coenzyme A (Acetyl-CoA). Acetyl-CoA, also known as activated acetic acid, is crucial in the production of nutrients, i.e., proteins, carbohydrates and lipids, and thus plays a key role in the metabolism of all cells.
Until now, it was unclear how bacteria coordinate the production and decomposition of activated acetic acid using this pathway. New findings published in the journal Nature Communications have now shown that Bacillus subtilis uses a special regulatory mechanism to coordinate both processes.
When cells are supplied with an abundance of nutrients, they are forced to decide whether to gain energy or create building blocks for growth. At the heart of this decision-making process is acetyl coenzyme A, which links the decomposition of nutrients with the synthesis of proteins, carbohydrates and lipids, thereby acting as a central hub for the entire metabolism during cell formation.
Waymo unveils virtual driver model to test autonomous car crash avoidance
Autonomous vehicles are already a reality on some of our streets and could become a major part of future transportation systems. Safety, of course, is the main concern, as with all vehicles. To help evaluate and improve its autonomous driving technology, U.S. driverless vehicle company Waymo has created a virtual representation of human driver behavior in near-crash situations.
Human drivers avoid collisions by instantly perceiving a hazard, deciding how to react and then executing the maneuver. It all happens in a split second thanks to the central and peripheral nervous systems working together harmoniously.
Currently, testing and training for collision avoidance involve several systems, and each often tests only a specific scenario or metric. For example, one system might only look at what happens when a lead vehicle brakes suddenly. They do not capture the whole sequence of events from detection to actual avoidance.
New water-based material could store solar energy, power reactions in darkness, then recharge
Northwestern University scientists have developed a new liquid material that charges like a battery, transforms like a living organism and then resets itself in open air. Traditionally, harvesting energy, storing it and using it require separate materials or devices. The new platform merges all three functions into a single material, opening the door for adaptive, clean, renewable systems that don’t require plastics or metals.
The study is published in Chem. It marks the first report of a material that stores energy by physically rebuilding itself.
To design the material, the researchers drew inspiration from the cytoskeleton —a cell’s dynamic internal scaffold that enables it to maintain its shape, move and divide. Unlike animals’ rigid skeletons, cytoskeletons constantly build, dismantle and rebuild themselves. Northwestern’s new material behaves in a similar way, repeatedly assembling and disassembling as it stores and releases energy. But instead of running on biological fuels, it is powered by electrons harvested from sunlight, electricity, X-rays and other energy sources.
Researchers identify brain ‘entrapment’ patterns associated with depression
Researchers at the Icahn School of Medicine at Mount Sinai have identified distinctive patterns in how the brain transitions between activity states in people with depression, providing new insight into why depressive symptoms can feel persistent and difficult to overcome.
Published online in Nature Communications, the study combined advanced neuroimaging techniques with mathematical modeling to examine how the brain moves between functional activity states over time. The findings suggest that depression may involve a form of “brain-state entrapment,” in which the brain becomes more likely to enter certain patterns of activity and less likely to transition out of them.
“Many patients describe depression as feeling stuck in negative patterns of thought, mood and behavior,” said Yael Jacob, Ph.D., assistant professor of psychiatry at the Dennis S. Charney, MD, Depression and Anxiety Discovery Center at the Icahn School of Medicine at Mount Sinai and senior author of the paper. “Our findings suggest that this experience of being ‘stuck’ may reflect measurable changes in the brain’s underlying dynamics.”