Phosphoric acid is vital in both biology and modern technology because of its exceptional ability to move electrical charge. Inside the human body and in devices such as fuel cells, this small molecule helps drive essential chemical reactions.
Scientists at the Department of Molecular Physics at the Fritz Haber Institute have now uncovered new details about how it performs this task at the molecular level.
Many central issues with which neurosciences is concerned, such as how we perceive the world around us, how we learn from experience, how we remember, how we direct our movements, and how we communicate with each other, have commanded the attention of thoughtful men and women for centuries. But it was not until after World War II that neuroscience began to emerge as a separate and increasingly vigorous scientific discipline that has as its ultimate objective providing a satisfactory account of animal (including human) behavior in biological terms. This ambitious goal has as its basis the central realization that all behavior is, in the last analysis, a reflection of the function of the nervous system. It is the organized and coordinated activity of the nervous system that ultimately manifests itself in the behavior of the organism. The challenge to neuroscience then, is to explain, in physical and chemical terms, how the nervous system marshalls its signaling units to direct behavior.
The real magnitude of this challenge can perhaps be best judged by considering the structural and functional complexity of the human brain and the bewildering complexity of human behavior. The human brain is thought to be composed of about a hundred billion (1011) nerve cells and about 10 to 50 times that number of supporting elements or glial cells. Some nerve cells have relatively few connections with other neurons or with such effector organs as muscles or glands, but the great majority receive connections from thousands of other cells and may themselves connect with several hundred other neurons. This means that at a fairly conservative estimate the total number of functional connections (known as synapses) within the human brain is on the order of a hundred trillion (1014). But what is most important is that these connections are not random or indiscriminate:
They constitute the essential “wiring” of the nervous system on which the extraordinarily precise functioning of the brain depends. We owe to the great neuroanatomists of the last century, and especially to Ramón y Cajal, the brilliant insight that cells with basically similar properties are able to produce very different actions because they are connected to each other and to the sensory receptors and effector organs of the body in different ways. One major objective of modern neuroscience is therefore to unravel the patterns of connections within the nervous system—in a word, to map the brain.
Researchers from Skoltech have published a paper in the journal Physica D: Nonlinear Phenomena presenting an analysis of steady propagating combustion waves—from slow flames to supersonic detonation waves. The study relies on the authors’ mathematical model, which captures the key physical properties of complex combustion processes and yields accurate analytical and numerical solutions. The findings are important for understanding the physical mechanisms behind the transition from deflagration to detonation, as well as for developing safer engines, fuel combustion systems, and protection against unwanted explosions in industrial settings.
The scientists identified several main types of combustion waves. The most powerful is strong detonation —a supersonic shock wave that sharply compresses and heats the mixture, triggering a chemical reaction. This type of wave is highly stable. In weak detonations and weak deflagration waves, there is no abrupt shock front.
The chemical reaction only begins if the mixture has been preheated to a temperature where it can ignite. These regimes occur rarely, under specific conditions, and can easily break down or transition into another wave type.
Future devices will continue to probe the frontier of the very small, and at scales where functionality depends on mere atoms, even the tiniest flaw matters. Researchers at Rice University have shown that hard-to-spot defects in a widely used two-dimensional insulator can trap electrical charges and locally weaken the material, making it more likely to fail at lower voltages. The findings are published in Nano Letters.
“By showing practical ways to detect when and where these defects form, we help make future devices more reliable and repeatable,” said Hae Yeon Lee, an assistant professor of materials science and nanoengineering at Rice, who is a corresponding author on the study.
Building ultrathin electronics such as advanced transistors, photodetectors and quantum devices involves stacking sheets of different 2D materials on top of each other into “heterostructures.” Hexagonal boron nitride (hBN), prized for being atomically flat and chemically stable, is a common building block.
A new material can store energy from sunlight and convert it into hydrogen days later. The material, jointly developed by researchers from Ulm and Jena, can do this even in the dark. The process is reversible and can be reactivated several times using a pH switch. The results are published in the journal Nature Communications.
Green hydrogen is one of the most important pillars of the energy transition. It is produced from sunlight using photocatalytic processes. There are now a variety of technologies for converting and storing solar energy into chemical energy. But now, for the first time, a material that can store the energy from sunlight for several days and then release it in the form of hydrogen “at the push of a button” has been successfully developed.
“You can think of it as a combination of a solar cell and a battery at the molecular level,” explains Professor Sven Rau, who heads the Institute of Inorganic Chemistry I at Ulm University.
Minor changes in moisture level can promote lipid molecules to reorganize themselves in biomaterial or biomembranes. This can affect how the skin, lungs and tear film protect us from dehydration. This new discovery from Lund University in Sweden could be the inspiration for smart materials and new drug delivery techniques.
Imagine a membrane that separates dry air from a moist interior. When moisture levels become lower, the lipid molecules organize themselves in an adaptive way—and now researchers in Lund have characterized this process.
“What surprised me was how powerful the sorting of the lipid molecules was even at small changes in the moisture level. I had not expected this based on what we know about the systems in conditions where there is no evaporation,” says Nikol Labecka, researcher in chemistry at Lund University.
In industrial plants around the world, tiny bubbles cause big problems. Bubbles clog filters, disrupt chemical reactions, reduce throughput during biomanufacturing, and can even cause overheating in electronics and nuclear power plants. MIT Professor Kripa Varanasi has long studied methods to reduce bubble disruption.
In a new study, Varanasi, along with Ph.D. candidate Bert Vandereydt and former postdoc Saurabh Nath, have uncovered the physics behind a promising type of debubbling membrane material that is “aerophilic”—Greek for “air-loving.” The material can be used in systems of all types, allowing anyone to optimize their machine’s performance by breaking free from bubble-borne disruptions.
“We have figured out the structure of these bubble-attracting membrane materials to allow gas to evacuate in the fastest possible manner,” says Varanasi, the senior author of the study.
If we are ever going to be go beyond the solar system, to share the miracle of Earth Life, it’s clear that we will need radical new ways of getting there.
One such solution that was recently proposed uses electron beams accelerated to near the speed of light to propel spacecraft, something that could overcome the vast distances between Earth and the next closest star. “For interstellar flight, the primary challenge is that the distances are so great,” Greason explained. “Alpha Centauri is 4.3 light-years away; about 2,000 times further away from the sun than the Voyager 1 spacecraft has reached — the furthest spacecraft we’ve ever sent into deep space so far. No one is likely to fund a scientific mission that takes much longer than 30 years to return the data — that means we need to fly fast.”
A study by Greason and Gerrit Bruhaug, a physicist at Los Alamos National Laboratory, published in the journal Acta Astronautica, highlights that reaching practical interstellar speeds hinges on the ability to deliver sufficient amounts of kinetic energy to the spacecraft in an economic way.
“Interstellar flight requires us to collect and control vast amounts of energy to achieve speeds fast enough to be useful,” said Greason. “Chemical rockets that we use today, even with the extra speed boost from flying by planets, or from […] swinging by the sun for a boost, just don’t have the ability to scale to useful interstellar speeds.”
When we think about biology, we usually picture chemistry: molecules bumping into each other, enzymes reacting, and signals spreading by diffusion. That picture is real—but it may be incomplete. In my recent paper in Harmonic Science Perspectives (Vol 1, Issue 1), I propose a complementary layer of cellular organization: a fast, coordination-capable “resonance network” that uses three interchangeable carriers of energy and information.
IntroductionA simple picture: three messengers that can translate into one anotherWhere this shows up in the body: mitochondria and microtubules as a coupled networkWhy interconversion matters: translation is the key featureResonant synchronization: a possible mechanism for cellular timingTherapeutic implications: why light and sound therapies might work better togetherA note on what’s established vs what’s proposedConclusion: a new lens on living organization
Those three carriers are light (photons), vibration/sound-like mechanical waves (phonons), and mobile electronic excitations in biomolecules (excitons). The central idea is simple to state even if the details are deep: living systems may continuously convert energy back and forth between these three modes to synchronize activity across space and time inside the cell—and potentially across tissues.
This essay is adapted from Traversal.
We look at a thing — a bird, a ball, a planet — and perceive it to be a certain color. But what we are really seeing is the color that does not inhere in it—the portion of the spectrum it shirks, the wavelength of light it reflects back unabsorbed. Our world appears a swirling miracle of blue, but its blueness is only a perceptual phenomenon arising from how our particular atmosphere, with its particular chemistry and its insentient stubbornness toward a particular portion of the spectrum, absorbs and reflects light.
In the living world beneath this atmosphere that scatters the shorter wavelengths as they pass, blue is the rarest color: There is no naturally occurring true blue pigment among living creatures. In consequence, only a slender portion of plants bloom in blue, and an even more negligible number of animals are bedecked with it, all having to perform various tricks with chemistry and the physics of light, some having evolved astonishing triumphs of structural geometry and optics to render themselves blue. Each feather of the blue jay is tessellated with tiny light-reflecting beads arranged to cancel out every wavelength of light except the blue.