A review of published meta-analyses examining protein supplementation found no evidence supporting intake beyond 1.6 grams per kilogram of body weight daily, according to an analysis by cardiologist Eric Topol. The review examined multiple randomized controlled trials encompassing thousands of participants. The most widely cited Morton study, which included 1,863 participants across 49 trials, showed no statistically significant benefit at higher protein levels, with a p-value of 0.079.
Recent research from Washington University identified the essential amino acid leucine as activating mTOR in macrophages, promoting atherosclerosis progression. The mechanism was demonstrated in both mouse models and human studies measuring circulating monocyte changes following acute high-protein challenges increasing dietary protein from 22% to 50% of energy intake. Current USDA data indicates 55% of American men and 35% of women already exceed the 0.8 g/kg/day recommendation from the National Academy of Medicine. The protein supplement industry, exemplified by David bars containing 28 grams of protein in 150 calories using a modified plant fat called EPG, projects $180 million in 2025 sales.
"According to a new study, wearing the right kind of perfume or cologne can enlarge your brain's gray matter," writes ScienceAlert
Researchers from Kyoto University and the University of Tsukuba in Japan asked 28 women to wear a specific rose scent oil on their clothing for a month, with another 22 volunteers enlisted as controls who put on plain water instead. Magnetic resonance imaging ( MRI) scans showed boosts in the gray matter volume of the rose scent participants.
While an increase in brain volume doesn't necessarily translate into more thinking power, the findings could have implications for neurodegenerative conditions such as dementia. "This study is the first to show that continuous scent inhalation changes brain structure," write the researchers in their published paper. We've seen scents like this improve memory and cognitive performance, but here the team wanted to try a longer-term experiment to see how triggering our sense of smell might lead to measurable changes in brain structure...
It's difficult to pin down exactly what's causing this boost in gray matter. Another possibility raised by the researchers is that the rose scent is actually labeled as unpleasant by the brain, with the subsequent emotional regulation responsible for the PCC working harder and increasing in size. The researchers hope that the findings could be useful in the development of aromatherapies that boost mental health and brain plasticity...
The research was published in the Brain Research Bulletin.
Plutôt S, ES ou L ? À la veille de la rentrée, souvenez-vous de ces séries qui ont marqué toute une génération. Du passé, désormais. Car la réforme Blanquer, effective depuis 2020, a bouleversé le lycée général. Modernisation nécessaire d’un système archaïque, ou nouvelle usine à gaz made in Éducation nationale ?
La seconde : une porte d’entrée préservée
En classe de seconde, peu de choses ont changé. Les élèves suivent toujours plus ou moins les mêmes matières, avec quelques options facultatives. La répartition horaire reste équilibrée, avec environ un tiers du temps consacré aux matières scientifiques « classiques » (maths, SVT, physique-chimie), un peu plus si l’on inclut les sciences numériques et technologiques (SNT), nouvelles venues dans le tronc commun. On pourrait juste regretter la faible place offerte aux sciences du vivant, reléguées en fond de grille depuis quelques décennies, alors que leurs enjeux (écologie, réchauffement climatique, agriculture, vaccination…) sont centraux dans le débat public.
À l’issue de la seconde, les élèves se répartissent entre le lycée technologique, peu chamboulé par la réforme, et le lycée général, qui accueille environ deux tiers des élèves.
Première et terminale générale : un casse-tête organisationnel
C’est là que la réforme change vraiment la donne. Fini les séries : désormais, un tronc commun assure un socle de culture générale (environ la moitié de l’emploi du temps), tandis que les élèves choisissent trois spécialités en première (4 h chacune), dont ils ne gardent que deux en terminale (6 h chacune).
Simple, vraiment ? En apparence peut-être. Car derrière cette façade se cache un véritable cauchemar organisationnel. En permettant d’innombrables combinaisons de spécialités, la réforme a dynamité les groupes-classes. Concrètement, on compose les classes autour du tronc commun, puis les élèves sont éclatés dans différents groupes pour leurs spécialités — soit 12 heures par semaine.
À l’arrivée, l’entraide entre élèves en prend un coup et les emplois du temps virent au casse-tête. Car il faut caler les spécialités au même moment de la semaine pour tout le monde, en plus de jongler avec les options, les groupes de langues et les dédoublements… Résultat : des emplois du temps individualisés, donc verrouillés à l’extrême. Déplacer une heure, organiser du soutien, programmer un devoir commun ? Mission quasi impossible.
Cerise sur le gâteau : on se retrouve avec des emplois du temps en gruyère, qui sapent l’efficacité et compliquent la vie de tous — des élèves comme des profs.
Et ce n’est pas tout. Le suivi des élèves prend aussi du plomb dans l’aile. Les professeurs de spécialité, éclatés sur plusieurs classes, ne peuvent tout simplement pas assister à tous les conseils. Résultat : certains sont clairsemés, privés bien souvent… des enseignants des matières principales. Quant aux professeurs principaux, forcément issus du tronc commun, ils disposent de trop peu d’heures avec leurs élèves pour réellement bien les connaître.
Plus de choix… mais moins de marge de manœuvre
Du côté des élèves, le constat est tout aussi négatif. Désormais, tout se joue en seconde. Le choix des spécialités, déterminant pour le traitement des vœux sur Parcoursup, conditionne l’orientation post-bac. Avant la réforme, au temps des séries, il suffisait de se situer globalement dans un profil ; aujourd’hui, dès leur première année de lycée, les jeunes doivent faire un choix crucial pour leur avenir, souvent sans avoir la moindre idée de leur projet et sans nécessairement disposer de la maturité requise.
Ainsi, paradoxalement, la prétendue flexibilité se mue en spécialisation imposée, aggravée par la suppression de la troisième spécialité en terminale. Au final, on retrouve des élèves piégés dans leurs choix. Une fois embarqués, nul retour en arrière possible : de la première au bac, le parcours est verrouillé. Et les lycéens le confirment eux-mêmes : ce système ne fait que leur ajouter du stress, ce qui est parfaitement compréhensible.
Et les sciences, dans tout ça ?
Les sciences paient un lourd tribut. Dans le tronc commun, leur enseignement est marginalisé avec seulement 2 heures par semaine, soit deux fois moins que le français ou les langues vivantes. Les programmes, souvent déconcertants, peinent à transmettre une véritable culture scientifique (cf. encart). Maigre compensation : depuis la rentrée 2023, les maths ont fait leur retour dans le tronc commun pour les élèves n’ayant pas opté pour la spécialité… mais seulement à raison d’1 h 30 par semaine, et uniquement en première.
Du côté des spécialités scientifiques, la situation est aussi préoccupante. Pendant des décennies, la série S jouissait d’une image flatteuse. Réputée exigeante, elle imposait moins de spécialisation que les autres séries en conservant la majorité des matières. Il était clair qu’avec un bac S en poche, toutes les portes post-bac étaient ouvertes. Cette filière aimantait ainsi naturellement les élèves indécis, souvent parmi les plus sérieux…
L’enseignement scientifique sacrifié sur l’autel de la modernité
Casser cette hégémonie pouvait sembler un objectif légitime de la réforme. Mais le prix payé est lourd, car les filières scientifiques en sortent fragilisées. La liberté de choix des spécialités a mis les matières en concurrence et, dans ce contexte, les disciplines scientifiques, parfois jugées trop difficiles ou trop calculatoires, séduisent moins. Si, avant la réforme, plus de la moitié des lycéens choisissaient la série S, aujourd’hui, à peine un tiers conserve deux spécialités scientifiques en terminale, un net décrochage au profit des autres matières.
On pourrait tenter de relativiser ces problèmes en supposant que cette évolution corrige simplement l’anomalie qui attirait dans la série S des élèves peu scientifiques. Mais là où les choses se compliquent, c’est que ces tendances se répercutent sur le supérieur : comme le souligne le collectif « Maths&Sciences » dans une tribune du Monde en 2024, les effectifs en première année d’école d’ingénieur, qui étaient en hausse constante depuis les années 2000, diminuent depuis la réforme (cf. figure).
Un constat inquiétant alors que les besoins dans les métiers exigeant un haut niveau de compétences scientifiques et technologiques continuent de croître.
Des spécialités inséparables
Dernier point délicat : la liberté de choix des spécialités se heurte à l’interdépendance des matières scientifiques. La physique-chimie exige des bases solides en maths, tandis que les SVT reposent souvent sur ces deux matières. Conséquence : un élève ayant jeté son dévolu sur la physique-chimie, mais non les maths, rencontrera rapidement des difficultés. De plus, de nombreuses filières post-bac, notamment celles axées sur les sciences du vivant, requièrent un niveau correct dans les trois disciplines scientifiques. Or, en terminale, les élèves ne conservent que deux spécialités. L’option « maths complémentaires » (qui avait été créée pour pallier ce problème) ne suffit pas toujours, et beaucoup en viennent à abandonner les SVT en terminale pour se tourner vers médecine ou STAPS, filières qui, paradoxalement, dépendent majoritairement de cette matière.
La réforme Blanquer a voulu moderniser le lycée et offrir plus de liberté aux élèves. Mais dans les faits, cette flexibilité crée du stress, complique l’organisation et fragilise l’enseignement des sciences. Une fois encore, le mieux s’est révélé l’ennemi du bien. En voulant abolir le carcan des séries, on a instauré un système qui ne satisfait personne.
Le véritable progrès pourrait finalement passer par un retour à plus de simplicité, quitte à réduire la liberté de choix. Un véritable « choc de simplification » permettrait de clarifier le fonctionnement du lycée, d’en accroître l’efficacité et de redonner aux sciences la place qu’elles méritent.
By exploiting two-color beams, researchers "can generate ordered chains and lattices," reports ScienceDaily, "with tunable topology — potentially revolutionizing data storage, communications, and photonic processing."
An internationally joint research group between Singapore and Japan has unveiled a blueprint for arranging exotic, knot-like patterns of light into repeatable crystals that extend across both space and time. The work lays out how to build and control "hopfion" lattices using structured beams.. three-dimensional topological textures whose internal "spin" patterns weave into closed, interlinked loops.
They have been observed or theorized in magnets and light fields, but previously they were mainly produced as isolated objects. The authors show how to assemble them into ordered arrays that repeat periodically, much like atoms in a crystal, only here the pattern repeats in time as well as in space. The key is a two-color, or bichromatic, light field whose electric vector traces a changing polarization state over time. By carefully superimposing beams with different spatial modes and opposite circular polarizations, the team defines a "pseudospin" that evolves in a controlled rhythm. When the two colors are set to a simple ratio, the field beats with a fixed period, creating a chain of hopfions that recur every cycle. Starting from this one-dimensional chain, the researchers then describe how to sculpt higher-order versions whose topological strength can be dialed up or down...
Topological textures like skyrmions have already reshaped ideas for dense, low-error data storage and signal routing. Extending that toolkit to hopfion crystals in light could unlock high-dimensional encoding schemes, resilient communications, atom trapping strategies, and new light-matter interactions. "The birth of space-time hopfion crystals," the authors write, opens a path to condensed, robust topological information processing across optical, terahertz, and microwave domains.
Longtime Slashdot reader cristiroma shares a report from New Atlas: Wouldn't it be great if the plants in your home could do more than just sit there looking pretty? Researchers at South China Agricultural University in the city of Guangzhou have found a way to upgrade them into soft glowing night lights in a range of hues, with the use of nanoparticles. The team developed a light-emitting phosphor compound that enabled succulents with fleshy leaves to charge in sunlight or indoor LED light in just a couple of minutes, and then emit a soft uniform glow that lasts up to two hours. The afterglow phosphor compound -- which is similar to those found in glow-in-the-dark toys -- is inexpensive, biocompatible, and negates the need for more complex methods of infusing bioluminescence in plants, like genetic modification. It simply gets injected into the leaves.
[...] Beyond modifying a commercial compound for this project, the team also had to figure out the right size for the phosphor particles so they'd work as intended inside plants. Shuting Liu, first author on the study that appeared in Matter this week, noted, "Smaller, nano-sized particles move easily within the plant but are dimmer. Larger particles glowed brighter but couldn't travel far inside the plant." Through extensive testing, the researchers arrived at an optimal size of around 7 micrometers, about the width of a red blood cell. They also determined through experimentation that the particles worked best in succulents, rather than plants with thinner leaves like bok choy.
Once they'd landed on the right particle size, loading concentration, and plant type, the team found that the phosphor material diffused into succulent leaves almost instantly, and uniformly lit up entire leaves -- enough to illuminate nearby objects. The scientists were also able to create modified phosphors that glowed in colors like green, red, and blue. That could make for novel indoor or garden decor, as well as pathway lighting. These luminous plants also don't cost much -- according to Liu, "Each plant takes about 10 minutes to prepare and costs a little over 10 yuan (about $1.4), not including labor." Over the course of 10 days, the injected plants didn't show any signs of damage, yellowing, structural integrity, or even reduced levels of chlorophyll.
Every breath people take in their homes or car probably contains significant amounts of microplastics small enough to burrow deep into lungs, new peer-reviewed research finds, bringing into focus a little understood route of exposure and health threat. The Guardian: The study, published in the journal Plos One, estimates humans can inhale as much as 68,000 tiny plastic particles daily. Previous studies have identified larger pieces of airborne microplastics, but those are not as much of a health threat because they do not hang in the air as long, or move as deep into the pulmonary system.
The smaller bits measure between 1 and 10 micrometers, or about one-seventh the thickness of a human hair, and present more of a health threat because they can more easily be distributed throughout the body. The findings "suggest that the health impacts of microplastic inhalation may be more substantial than we realize," the authors wrote.
"The truly universal properties of languages are not independent of our physiology and cognition," argues the co-author of a new study. Instead he says their research "strengthens the idea that intonation units are a universal feature of language."
Phys.org explains:
Have you ever noticed that a natural conversation flows like a dance — pauses, emphases, and turns arriving just in time? A new study has discovered that this isn't just intuition; there is a biological rhythm embedded in our speech...
According to the study, led by Dr. Maya Inbar, alongside Professors Eitan Grossman and Ayelet N. Landau, human speech across the world pulses to the beat of what are called intonation units, short prosodic phrases that occur at a consistent rate of one every 1.6 seconds. The research analyzed over 650 recordings in 48 languages spanning every continent and 27 language families. Using a novel algorithm, the team was able to automatically identify intonation units in spontaneous speech, revealing that regardless of the language spoken, from English and Russian to endangered languages in remote regions, people naturally break their speech into these rhythmic chunks. "These findings suggest that the way we pace our speech isn't just a cultural artifact, it's deeply rooted in human cognition and biology," says Dr. Inbar.
"We also show that the rhythm of intonation units is unrelated to faster rhythms in speech, such as the rhythm of syllables, and thus likely serves a different cognitive role...." Most intriguingly, the low-frequency rhythm they follow mirrors patterns in brain activity linked to memory, attention, and volitional action, illuminating the profound connection between how we speak and how we think.
The work is published in the journal Proceedings of the National Academy of Sciences.
Des scientifiques auraient trouvé des compléments alimentaires pour les abeilles permettant de multiplier par 15 la taille des essaims. 😮
Ça pourrait aider à pallier à la disparition des insectes. (Permalink)
alternative_right shares a report from Phys.org: Now, for the first time, quantum scientists at the Quantum Control Laboratory at the University of Sydney Nano Institute have demonstrated a type of quantum logic gate that drastically reduces the number of physical qubits needed for its operation. To do this, they built an entangling logic gate on a single atom using an error-correcting code nicknamed the "Rosetta stone" of quantum computing. It earns that name because it translates smooth, continuous quantum oscillations into clean, digital-like discrete states, making errors easier to spot and fix, and importantly, allowing a highly compact way to encode logical qubits.
The curiously named Gottesman-Kitaev-Preskill (GKP) code has for many years offered a theoretical possibility for significantly reducing the physical number of qubits needed to produce a functioning "logical qubit." Albeit by trading efficiency for complexity, making the codes very difficult to control. Research published in Nature Physics demonstrates this as a physical reality, tapping into the natural oscillations of a trapped ion (a charged atom of ytterbium) to store GKP codes and, for the first time, realizing quantum entangling gates between them.
Led by Sydney Horizon Fellow Dr. Tingrei Tan at the University of Sydney Nano Institute, scientists have used their exquisite control over the harmonic motion of a trapped ion to bridge the coding complexity of GKP qubits, allowing a demonstration of their entanglement. "Our experiments have shown the first realization of a universal logical gate set for GKP qubits," Dr. Tan said. "We did this by precisely controlling the natural vibrations, or harmonic oscillations, of a trapped ion in such a way that we can manipulate individual GKP qubits or entangle them as a pair." [...] Across three experiments described in the paper, Dr. Tan's team used a single ytterbium ion contained in what is known as a Paul trap. This uses a complex array of lasers at room temperature to hold the single atom in the trap, allowing its natural vibrations to be controlled and utilized to produce the complex GKP codes. This research represents an important demonstration that quantum logic gates can be developed with a reduced physical number of qubits, increasing their efficiency.
Reviewers are more likely to approve a manuscript if their own work is cited in subsequent versions than are reviewers who are not cited, according to an analysis of 18,400 articles from four open-access publications. From a report: The study, which is yet to be peer reviewed, was posted online as a preprint earlier this month. The study was inspired by anecdotes from authors who cited articles only because reviewers asked them to, says study author Adrian Barnett, who researches peer review and meta-research at Queensland University of Technology in Brisbane, Australia. Sometimes, these requests are fine, he says. But if reviewers ask for too many citations or the reason to cite their work is not justified, the peer-review process can become transactional, says Barnett. Citations increase a researcher's h-index, a metric reflecting the impact of their publications.
An anonymous reader quotes a report from Reuters: Serbian scientists have been experimenting with mealworms as a way to break down polystyrene. Larisa Ilijin, a principal research fellow at Belgrade's Institute for Biology, said the scientists had discovered that mealworms can digest various plastics, including polystyrene, which is used in packaging, insulation and food containers. In the project endorsed by the government and the United Nations' agency for international development, UNDP, and other international donors, they have been including the polystyrene in the regular food of the larval form of the yellow mealworm beetle, or Tenebrio molitor.
They habitually eat more or less anything, but need the training to eat the plastic products. "We have larvae that have been adapted over a long time to biodegrade plastic, to be as efficient as possible in the process," Ilijin told Reuters. She said the bacteria living in their guts break down the plastic into carbon dioxide and water, and showed no evidence of leaving microplastic residue in their innards or faeces. The work builds on similar research projects in the U.S. and Africa. [...]
The institute has given Belgrade-based Belinda Animals several containers of the mealworms. It is now breeding them and hoping to attract a network of similar farms. "When breaking down 1 kg of Styrofoam, larvae emit one to two grams of carbon dioxide ... If we incinerate it ... (Styrofoam) emits over 4,000 times more," owner Boris Vasiljev said. He also envisages the larvae being used as animal feed, should it reach a large commercial scale.
The use of mealworms is still in its infancy, Ilijin said, as Serbia still needs to adopt regulations that would allow the use and sale of insect products for animal fodder. "Styrofoam takes over 500 years to decompose in nature ... this would be one of the good ways for solving the problem of plastic waste in nature," Ilijin said.
A new review of nearly 700 studies on portable air cleaners found that over 90% of them were tested in empty spaces, not on people, leaving major gaps in evidence about whether these devices actually prevent infections or if they might even cause harm by releasing chemicals like ozone or formaldehyde. The Conversation reports: Many respiratory viruses, such as COVID-19 and influenza, can spread through indoor air. Technologies such as HEPA filters, ultraviolet light and special ventilation designs -- collectively known as engineering infection controls -- are intended to clean indoor air and prevent viruses and other disease-causing pathogens from spreading. Along with our colleagues across three academic institutions and two government science agencies, we identified and analyzed every research study evaluating the effectiveness of these technologies published from the 1920s through 2023 -- 672 of them in total.
These studies assessed performance in three main ways: Some measured whether the interventions reduced infections in people; others used animals such as guinea pigs or mice; and the rest took air samples to determine whether the devices reduced the number of small particles or microbes in the air. Only about 8% of the studies tested effectiveness on people, while over 90% tested the devices in unoccupied spaces.
We found substantial variation across different technologies. For example, 44 studies examined an air cleaning process called photocatalytic oxidation, which produces chemicals that kill microbes, but only one of those tested whether the technology prevented infections in people. Another 35 studies evaluated plasma-based technologies for killing microbes, and none involved human participants. We also found 43 studies on filters incorporating nanomaterials designed to both capture and kill microbes -- again, none included human testing.
Si vous ne connaissez pas cette série d'animation sur la science, foncez ! C'est scientifiquement exacte et très drôle.
(Il faudra que je prenne le temps de tout télécharger pour ne pas perdre ça.) (Permalink)
Sunlight becomes energy when plants convert four photons of light. But unfortunately, most attempts at synthetic light-absorbing chemicals can only absorb one photon at a time, write two researchers from the University of Melbourne.
"In the Polyzos research group at the School of Chemistry, we have developed a new class of photocatalysts that, like plants, can absorb energy from multiple photons."
This breakthrough allows us to harness light energy more effectively, driving challenging and energy-demanding chemical reactions.
We have applied this technology to generate carbanions — negatively charged carbon atoms that serve as crucial building blocks in the creation, or synthesis, of carbon- and hydrogen-rich chemicals known as organic chemicals. Carbanions are vital in making drugs, polymers and many other important materials. However, traditional methods to produce carbanions often require lots of energy and dangerous reagents, and generate significant chemical waste, posing environmental and safety challenges... Our new method offers a greener, safer alternative [using visible light and renewable starting materials]...
We've used it to synthesize important drug molecules, including antihistamines, in a single step using simple, cheap and commonly available "commodity chemicals" — amines and alkenes. And importantly, the reaction scales well in commercial-scale continuous flow reactors, highlighting its potential for industrial applications.
"By learning from the subtle mastery of photosynthesis," the researchers write, their group "is forging a new paradigm for chemical manufacturing — one where sunlight powers sustainable and elegant solutions for the molecules that shape our world."
New research suggests exposure to some common Pfas or "forever chemical" compounds causes changes to gene activity, and those changes are linked to health problems including multiple cancers, neurological disorders and autoimmune disease. From a report: The findings are a major step toward determining the mechanism by which the chemicals cause disease and could help doctors identify, detect and treat health problems for those exposed to Pfas before the issues advance. The research may also point toward other diseases potentially caused by Pfas that have not yet been identified, the authors said.
The study is among the first to examine how Pfas chemicals impact gene activity, called epigenetics. "This gives us a hint as to which genes and which Pfas might be important," said Melissa Furlong, a University of Arizona College of Public Health Pfas researcher and study lead author.
A countrywide study of smartphone users who relocated between US cities found that moving to more walkable environments increased daily walking by 1,100 steps on average. Stanford University researchers analyzed 248,266 days of step data from 5,424 users of the Azumio Argus smartphone app who relocated 7,447 times among 1,609 cities between March 2013 and February 2016. Participants who moved from cities at the 25th percentile of walkability to those at the 75th percentile sustained the increased activity levels for at least three months after relocation.
The additional steps consisted predominantly of moderate-to-vigorous physical activity, with large walkability increases of 49-80 points associated with about one hour per week more of such activity. The study found that 42.5% of participants met national physical activity guidelines for moderate-to-vigorous activity after moving to highly walkable locations, compared to 21.5% before relocation. Computer simulations based on the data suggest that increasing all US cities to the walkability level of Chicago or Philadelphia could result in 36 million more Americans meeting aerobic physical activity guidelines.
An anonymous reader quotes a report from MIT Technology Review: Physicists have created a new type of radar that could help improve underground imaging, using a cloud of atoms in a glass cell to detect reflected radio waves. The radar is a type of quantum sensor, an emerging technology that uses the quantum-mechanical properties of objects as measurement devices. It's still a prototype, but its intended use is to image buried objects in situations such as constructing underground utilities, drilling wells for natural gas, and excavating archaeological sites. [...] The glass cell that serves as the radar's quantum component is full of cesium atoms kept at room temperature. The researchers use lasers to get each individual cesium atom to swell to nearly the size of a bacterium, about 10,000 times bigger than the usual size. Atoms in this bloated condition are called Rydberg atoms.
When incoming radio waves hit Rydberg atoms, they disturb the distribution of electrons around their nuclei. Researchers can detect the disturbance by shining lasers on the atoms, causing them to emit light; when the atoms are interacting with a radio wave, the color of their emitted light changes. Monitoring the color of this light thus makes it possible to use the atoms as a radio receiver. Rydberg atoms are sensitive to a wide range of radio frequencies without needing to change the physical setup... This means a single compact radar device could potentially work at the multiple frequency bands required for different applications.
[Matthew Simons, a physicist at the National Institute of Standards and Technology (NIST), who was a member of the research team] tested the radar by placing it in a specially designed room with foam spikes on the floor, ceiling, and walls like stalactites and stalagmites. The spikes absorb, rather than reflect, nearly all the radio waves that hit them. This simulates the effect of a large open space, allowing the group to test the radar's imaging capability without unwanted reflections off walls.The researchers placed a radio wave transmitter in the room, along with their Rydberg atom receiver, which was hooked up to an optical table outside the room. They aimed radio waves at a copper plate about the size of a sheet of paper, some pipes, and a steel rod in the room, each placed up to five meters away. The radar allowed them to locate the objects to within 4.7 centimeters. The team posted a paper on the research to the arXiv preprint server in late June.
Researchers at Kyushu University have developed a solid-oxide fuel cell that operates at just 300C, less than half the usual operating temperature. The team was able to do this by engineering a "ScO6 highway" in the electrolyte, allowing protons to move quickly without losing performance. "The team expects that their new findings will lead to the development of low-cost, low-temperature SOFCs and greatly accelerate the practical application of these devices," said the researchers in a press release. Interesting Engineering reports: "While SOFCs are promising due to their high efficiency and long lifespan, one major drawback is that they require operation at high temperatures of around 700-800C (1292F-1472F)," added the researchers in a press release. Such heat requires costly, specialized heat-resistant materials, making the technology expensive for many applications. A lower operating temperature is expected to reduce these manufacturing costs.
The team's success comes from re-engineering the fuel cell's electrolyte, the ceramic layer that transports protons (hydrogen ions) to generate electricity. Previously, scientists faced a trade-off. Adding chemical dopants to an electrolyte increases the number of available protons but also tends to clog the material's crystal lattice, slowing proton movement and reducing performance. The Kyushu team worked to resolve this issue. "We looked for oxide crystals that could host many protons and let them move freely -- a balance that our new study finally struck," stated Yamazaki.
They found that by doping two compounds, barium stannate (BaSnO3) and barium titanate (BaTiO3), with high concentrations of scandium (Sc), they could create an efficient structure. Their analysis showed that the scandium atoms form what the researchers call a "ScO6 highway." This structure creates a wide and softly vibrating pathway through the material. "This pathway is both wide and softly vibrating, which prevents the proton-trapping that normally plagues heavily doped oxides," explained Yamazaki. The resulting material achieves a proton conductivity of more than 0.01 S/cm at 300C, a performance level comparable to conventional SOFC electrolytes that run at more than double the temperature. The research has been published in the journal Nature Materials.
People who experience nightmares weekly or more frequently face three times higher risk of dying before age 70 compared to those having nightmares less than monthly, according to research by Dr. Abidemi Otaiku at Imperial College London. His analysis of six long-term studies covering more than 180,000 adults and 2,500 children found frequent nightmares predict early death more strongly than smoking, obesity, poor diet, or physical inactivity.
Among 174 people who died prematurely, 31 experienced at least weekly nightmares. Otaiku's research shows chromosomes of nightmare-prone individuals display accelerated aging patterns linked to stress hormones, accounting for roughly 40% of their increased mortality risk. Effective nightmare treatment options are currently limited and require more medical research, the report adds.
Computer scientists at Tsinghua University and Stanford have developed an algorithm that surpasses a fundamental speed limit that has constrained network pathfinding calculations since 1984. The team's approach to the shortest-path problem -- finding optimal routes from one point to all others in a network -- runs faster than Dijkstra's 1956 algorithm and its improvements by avoiding the sorting process that created the decades-old computational barrier.
Led by Ran Duan at Tsinghua, the researchers combined clustering techniques with selective application of the Bellman-Ford algorithm to identify influential nodes without sorting all paths by distance. The algorithm divides graphs into layers and uses Bellman-Ford to locate key intersection points before calculating paths to other nodes. The technique works on both directed and undirected graphs with arbitrary weights, solving a problem that stymied researchers after partial breakthroughs in the late 1990s and early 2000s applied only to specific weight conditions.
Connexion
