It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Thursday, May 28, 2026
Good Vitamin D status among most young children in Sweden
The majority of young children showed good vitamin D status, no child had indications of deficiency, but among some intake was too low. This is the result of a study encompassing over 1,800 infants in Sweden. Foods providing children with vitamin D also contributed to greenhouse gas emissions.
This study is the first to offer an in-depth analysis of vitamin D intake and status among infants in Sweden following an expansion of mandatory vitamin D fortification in 2018. The initiative focused on certain food groups and the aim was to ensure that more people attain sufficient vitamin D through their diet.
The study included children aged 18 months (1,074 individuals) and four years (746 individuals) whose data were obtained from the survey “Riksmaten småbarn”, covering 2021-2024. The study also evaluated the climate impact of foods providing children with vitamin D.
Low intake but no deficiency
The results show that 16 percent of the 18-month-olds and 61 percent of the four-year-olds were below the average required vitamin D intake (7.5 microgram/day) through diet and vitamin D drops. No children were vitamin D deficient, and most children had sufficient levels, including 93 percent in the younger age group and 96 percent in the older age group.
The most important sources of vitamin D for 18-month-olds were vitamin D drops and fortified dairy products, porridge and cereals; and for the four-year-olds, fortified dairy products and spreads.
At the same time, dairy products contribute to diet-related greenhouse gas emissions. The foods with the highest vitamin D content relative to environmental impact were fortified spreads and fortified plant-based alternatives. This makes plant-based alternatives a climate-friendly source of vitamin D.
Climate impact can be reduced
The study, published in the Nutrition Journal, was conducted by researchers at the University of Gothenburg, Swedish Food Agency and RISE, Research Institutes of Sweden. One of the lead authors is André Hesselink, dietician and doctoral student in clinical nutrition at the University of Gothenburg:
“We have enjoyed an excellent collaboration with the Swedish Food Agency, and our results show the crucial importance of fortified dairy products for vitamin D intake among young children in Sweden, especially after they stop taking vitamin D drops. In addition, the expansion of the mandatory fortification programme provides an opportunity for plant-based alternatives to play a more prominent role in the future for ensuring adequate intake of vitamin D and reducing the climate impact of our dietary habits”, he says.
Fact box: Vitamin D
Required for the formation of strong teeth and bones
One of few vitamins that we risk ingesting too little of
Stored in the body over time
Ingested through diet, mainly from fatty fish and fortified foods
Formed in the skin by exposure to sunlight (dark skin requires more exposure time)
Recommended for children in Sweden from 0-2 years of age in the form of supplemental vitamin D drops
High proportion of young children are vitamin D sufficient after expansion of Sweden’s mandatory fortification but dairy products also contribute to a high climate impact
Monash students unveil cave safety tech as Laos rescue continues
The student team created ANTRUM, a wearable tracking and navigation system,, designed for high-risk underground settings such as caves and mines, where GPS and phone signals are often unavailable.
The palm-sized devices are strapped to a user’s leg before entering an underground environment. Using motion sensors and radio communication, it allows users to locate their exploration partner and navigate back towards the cave entrance from the point where route recording began.
The team developed a complete working system, including hardware, software, electronics and a 3D-printed casing. They are now hoping to develop a waterproof version that could support underwater cave divers.
The project was inspired by the 2018 rescue of the Thai youth soccer team trapped in the Tham Nang Non cave system in Thailand's Chiang Rai province.
“We were inspired by the story of the Thai youth soccer team cave rescue and wanted to explore whether technology could help prevent people from becoming stranded in the first place,” said project team member Maria Demina, who is studying a Bachelor of Electrical Engineering.
ANTRUM also includes a web dashboard, ANTRUM DASH, which records movement data during use. Once users return to the surface, the data uploads to the cloud, allowing them to review and analyse their route.
The development comes at a critical time and highlights the growing need for technology that can help prevent people becoming trapped underground.
Risk of renewable power fluctuations made predictable
Giant dataset of electricity generation and weather conditions informs new physics-based framework that helps mitigate grid fluctuations and inform wind farm placements
Okinawa Institute of Science and Technology (OIST) Graduate University
One of the key challenges to climate-neutral power generation is addressing the risk of unpredictable power surges from renewables. Even with advanced turbine design or battery storage, a gust of wind or changing atmospheric conditions can cause a sudden spike in power output. This overgeneration can rapidly escalate up to volatile, potentially dangerous grid-wide surges and blackouts as generators become larger and more efficient, farms increase in size and number, and renewables take up an increasing fraction of total power production.
In a paper now published in PRX Energy, researchers from the Nonlinear and Non-equilibrium Physics Unit at Okinawa Institute of Science and Technology (OIST) present a new statistical framework for predicting power fluctuations of individual wind turbines, wind farms, and groups of farms, as well as voltage fluctuations of entire grids, using existing geospatial information. With this, energy policymakers, engineers, and grid operators have a powerful tool for understanding and predicting the risks associated with the turbulent behavior of wind power generation.
“With our statistical analysis, farm designers can now create physics-based predictors for assessing power fluctuation risks based on the specific placement of current or future turbines and farms. It’s a bit like financial forecasting,” says study first author Dr. Samy Lakhal.
Translating turbulence to risk via a 20km wide physics experiment
The researchers derived the statistical framework using wind and power-generation data from 80 wind turbines in the United States, spread over 20km, collected every 10 minutes for more than 5 years. Senior author Professor Mahesh Bandi continues:
“We found that the wind farm behaved less like a collection of independent wind turbines, and more like a single, turbulent system. Power fluctuations correlate strongly with atmospheric turbulence, which gives a very strong indication of the total variation in electricity output for a given farm. And these fluctuations scale predictably across downwind farms and the entire energy grid.”
With this framework in hand, planners can accurately assess the risk profiles of existing turbines and farms, as well as future developments. The predictors also scale to help evaluate the fluctuation risks associated with connecting new facilities to the power grid.
Scale up diversification and collaboration
Renewables are expected to overtake coal in global power generation by the end of 2026. As wind power megaprojects come online — last year alone, 165 gigawatts of wind power were installed, a 40% year-over-year increase — addressing the risk of power surges becomes increasingly urgent.
“Ultimately, the most reliable strategy is to diversify the geographic placement of wind turbines to mitigate the risks of overproduction. A sparse distribution of both turbines and farms reduces large-scale fluctuations, as does a diversity of power generation methods. And as more installations come online, we need better collaboration between grid and farm operators,” concludes Lakhal.
“We absolutely need more renewables. With the accurate predictions that this model can help establish, we can better manage the risks associated with large-scale implementation — and as global developments come online, diverse energy portfolios and sparse placements should themselves act as buffers against future fluctuations.”
Metamaterials – the term may sound esoteric to the layman. In science and engineering, however, this is an interesting field of research that has developed at a highly dynamic pace, particularly since the 1990s.
To the naked eye, a metamaterial looks like an ordinary material. On smaller scales, however, it features an unusual, carefully engineered structure, endowing it with special mechanical or physical properties that the original basic material does not possess.
Such artificially designed materials are, for example, very light, stiff, highly deformable, or they mitigate impact and attenuate vibrations. Applications range from shoe soles (as reported by ETH News) and helmets all the way to microelectronics.
Special properties thanks to a special microstructure
Dennis Kochmann, Professor of Mechanics and Materials Research at ETH Zurich has extensively worked on metamaterials in his research. “It is fascinating how, through a special microstructure, you can endow a material with special properties that it does not possess without this structure,” he explains.
Kochmann and his collaborators recently presented a novel so-called phononic metamaterial in two scientific publications – a material capable of precisely controlling mechanical waves, such as vibrations or acoustic signals.
Such a metamaterial could, for example, be deployed to harvest energy from vibrations or to process signals purely mechanically, which is of interest for sensors and mechanical computers that operate without electricity.
Wafer-thin silicon membrane as a wave guide
If a metal plate is excited to vibrate – for example, by hitting it with a hammer – these vibrations usually spread in a circular fashion, similar to surface waves in water. If this plate has a carefully designed structure, however, it can redirect waves along specific paths – and it is precisely this effect that the ETH researchers have exploited.
Instead of a metal plate, they used an extremely thin silicon membrane into which the researchers etched countless holes by way of photolithography and etching techniques, thereby forming a specific pattern.
A pattern comprising millions of elements
The pattern consists of millions of repeating square elements – minute squares, each further divided diagonally into four squares. At the centre of the main square is a four-pointed star.
Unlike in many other metamaterials, these unit cells are not identical across the entire pattern but change incrementally, as the lengths of the star’s arms vary.
The ETH researchers used custom-built computer models to generate these patterns and simulated how a wave striking the pattern propagates in rays.
“If one were to simulate the entire wave field in a conventional manner, it would be extremely computationally expensive, because the design space is huge with millions upon millions of degrees of freedom,” explains Kochmann’s former team member Charles Dorn, now an assistant professor at the University of Washington, who was in charge of the simulations.
Playing puzzle with metamaterials
“The design of our metamaterial is modular, just like a jigsaw puzzle,” as Kochmann explains. In this way, different puzzle pieces perform specific functions, such as deflecting rays at right angles or splitting waves into different directions based on their frequency. When the researchers skilfully assemble the appropriate puzzle pieces, they can generate complex wave paths, such as a figure-eight path.
Manufactured in the cleanroom on silicon substrates
In a further step, the researchers fabricated the computationally designed structures with high precision in the cleanroom at the Binnig and Rohrer Nanotechnology Centre at ETH Zurich and IBM. To this end, they used a conventional silicon wafer as the starting point and, in several steps, turned it into a silicon membrane that is structured exactly like the simulated pattern, with hundreds of thousands of unit cells – each measuring just a few micrometres in size and hence barely visible to the naked eye.
As a final step, the researchers tested the metamaterial membranes they had produced in an experiment. Using laser pulses, they caused the silicon membrane to vibrate. Deploying an optical measurement technique, they tracked the propagation of the vibrations in real time.
This enabled Kochmann and his colleagues to confirm that the waves did indeed follow the specified paths – and in some cases over long periods of time.
The structures not only function at a single vibration frequency: although the researchers designed the system for 750 kilohertz (750,000 vibrations per second), it operates effectively at frequencies ranging from around 250 to 800 kilohertz. “We hadn’t planned for this broad frequency range, so it came as a pleasant surprise,” comments Vignesh Kannan, co-author of the study published in the journal Nature Communications.
As silicon, the base material, has naturally low damping characteristics, waves can propagate for a long time. This is a major advantage over polymer-based 3D-printed structures, whose damping quickly suppresses any vibrations, explains Kannan, who is now an assistant professor at the École Polytechnique in Paris.
Harvesting energy from vibrations
The novel silicon membrane could find use in micro- and nanoelectronics, for example to better control vibrations on chips. The phononic metamaterial is also of interest for mechanical signal processing without a power supply, such as in sensors for monitoring infrastructure in remote areas. In the long term, they could also be deployed for novel computer architectures.
Kochmann, however, is also considering energy harvesters – devices that specifically direct vibration energy to piezoelectric energy converters, which generate usable electricity from vibrations.
In the next stages, he and his collaborators hope to push miniaturisation even further – right up to the limits of what is feasible, where manufacturing defects in the micro- or even nanostructure begin to have a significant impact.
“We also want to gain a better understanding of the physics behind the phenomena at play. It is not yet entirely clear why the design works so robustly across such a wide range of frequencies,” states Kochmann.
For him, basic research is the top priority, as some of the underlying phenomena still remain a mystery. Applications often arise naturally, as the researcher comments. “That’s the beauty of being here at ETH: we can try things out and explore the fundamentals without commercial pressure.”
References
Kannan V, Dorn C, Drechsler U, Kochmann DM: Microscale Architected Materials for Elastic Waveguiding: Fabrication and Dynamic Characterization across Length and Time Scales Phys. Rev. X 16, 011047 – Published 5 March, 2026, DOI: https://doi.org/10.1103/21w4-zn1s
Dorn C, Kannan V, Drechsler U, et al. Graded phononic metamaterials based on scalable microfabrication and design. Nat Commun 17, 3192 (2026). https://doi.org/10.1038/s41467-026-69888
Microscale Architected Materials for Elastic Waveguiding: Fabrication and Dynamic Characterization across Length and Time Scales Phys.
Disco lasers improve the safety of snow groomers
An international team involving Graz University of Technology has investigated how heavy machinery can be operated more safely using extended reality applications. In the process, a disco laser outdid VR headsets
When it comes to snow groomers, excavators or crane vehicles, how can their operation be optimised even in difficult conditions and made safer for people in and around the vehicle? An international research team, including the Institute of Visual Computing at Graz University of Technology (TU Graz), investigated this question as part of the THEIA-XR project. The researchers aimed to improve human-machine interaction through the use of extended reality technologies. The focus was on the operator, whose field of perception was to be expanded without negatively affecting control performance. When working with snow groomers, for example, the team from TU Graz found that data or VR headsets tend to be counterproductive, while information projected via a repurposed disco laser proved to be a great help.
Drawings in the snow
Wearing a VR headset for long periods was too strenuous for the neck muscles; moreover, due to the constant jolting movements on rough terrain, they quickly caused nausea in many people. Laser projection onto the terrain in front of the vehicle, on the other hand, proved to be a viable solution. This allows not only speed information but also tracks and orientation aids to be projected onto the snow, enabling a snow groomer to be steered more efficiently and safely. Virtual barriers and warning indicators for people in the vicinity of the vehicle further enhance safety. And in poor visibility, due to fog or snowfall, the laser beams become visible in the aerosols in the air, allowing structures to be visualised that lie beyond the available line of sight.
In addition to improving data visualisation for drivers, the team also carried out research on ways to better capture the surrounding environment. It became apparent that the researchers’ intentions and the practical benefits for vehicle occupants were not always the same. “The exciting thing about this project was that our considerations from a research perspective and the drivers’ needs first had to be reconciled,” says Clemens Arth from the Institute of Visual Computing at TU Graz. “For example, we developed what is probably a globally unique prototype for a 360-degree thermal imaging camera to show snow groomer drivers whether there were people or animals around the vehicle. Ultimately, however, the much greater benefit was that they could groom the slopes more accurately, as it became clear where the snow was well-compacted and where it wasn’t.”
Foundations for future remote control
The project also provided important foundations for the increased remote control of heavy machinery in the long term. The rationale behind this is to protect the health of the people in the vehicle, as physical injuries can occur rapidly, particularly when working in rough terrain due to constant vibrations. An important step towards reliable remote control was the improved depth perception in simple camera transmissions, enabling distances to be better assessed via a monitor.
In addition to TU Graz and the snow groomer manufacturer Prinoth, Dresden University of Technology was also involved in the project, conducting research on excavator vehicles in collaboration with Stuttgart Media University. The VTT Technical Research Centre of Finland, in collaboration with the Kalmar company, focused on forklifts and loading machines in port environments. The University of Luxembourg was responsible for the anonymisation of personal performance data and the non-discriminatory identification of individuals by sensors. The consortium was led by TTControl, while the Creanex Oy and Haption companies contributed simulator and control technology.
As the global transition toward carbon neutrality accelerates, "water electrolysis"—a technology that splits water electrically to produce clean hydrogen—is drawing significant attention. However, a major limitation has been the decline in efficiency caused by bubbles formed during the electrolysis process that block the pathways. A domestic research team has resolved this challenge by developing an innovative technology that rapidly discharges bubbles and boosts hydrogen production efficiency, much like clearing an expressway through a heavily congested road.
KAIST announced on May 28th that a research team led by Professor Jinwoo Lee from the Department of Chemical and Biomolecular Engineering, in collaboration with a research team led by Dr. Sungjun Kim from KRICT (President Suk-min Shin) and a research team led by Professor Jang Yong Lee from Konkuk University (President Jong-phil Won), has departed from the conventional method of simply increasing catalytic activity itself. Instead, they have successfully secured both water electrolysis performance and stability simultaneously by newly designing a "pathway" inside the catalyst layer through which water and gas pass.
Using paper-thin 2D mesoporous carbon (a thin carbon structure with numerous nanoscale pores) nanosheets, the research team created a low-tortuosity structure where materials can move without obstruction. Simply put, they implemented a "highway-like pathway" inside the catalyst layer through which water and gas can pass rapidly, instead of a narrow and complex alleyway.
Furthermore, ruthenium (Ru) nanoclusters (ultrafine metal particles several nanometers in size) were stably anchored onto the defect-introduced carbon surface to accelerate the hydrogen evolution reaction rate. Simultaneously, the interface structure was controlled to prevent catalyst degradation even during long-term operation.
Through this technology, it was confirmed that bubbles generated during the water electrolysis process were rapidly discharged without accumulating inside the catalyst layer, and a stable reaction was maintained even under extreme environments with high current density.
As a result, the technology recorded a world-class performance of 17.1 A cm⁻² at 80°C, vastly exceeding the 2026 target set by the U.S. Department of Energy (DOE). This figure represents the amount of current flowing per unit area; a higher value signifies that more hydrogen can be produced faster.
In addition, it demonstrated practical industrial applicability by operating stably for over 1,000 hours even under a low noble metal loading condition (0.09 mgRu cm⁻²). This means that the amount of ruthenium, a precious metal used in the catalyst, has been significantly reduced, which can also enhance the economic viability of water electrolysis systems.
The core of this research lies not simply in making a "good catalyst," but in newly designing the pathway itself through which hydrogen is formed. In conventional water electrolysis devices, bubbles generated during the reaction process accumulate inside, blocking the flow of water and electricity, which leads to a degradation in performance. The research team solved this problem by changing the structure of the catalyst layer so that bubbles can exit rapidly.
This technology holds great significance as it opens the way to produce eco-friendly hydrogen more affordably and efficiently in the future. Hydrogen is currently attracting attention as a core clean energy source for the carbon-neutral era, but it has faced limitations due to high production costs and low system efficiency. In particular, conventional high-performance water electrolysis devices required large amounts of expensive noble metals, making large-scale commercialization difficult.
The research team explained that this technology demonstrates the potential to achieve high performance and stability with only a small amount of noble metals. It is expected to expand into various fields in the future, including large-scale green hydrogen production, eco-friendly power generation systems, hydrogen vehicles/eco-friendly mobility, and carbon-neutral industrial processes.
Professor Jinwoo Lee stated, "This research is a technology that improves water electrolysis efficiency by designing not only the catalyst itself but also the path through which energy flows. Since high-efficiency green hydrogen production is possible with only a small amount of noble metals, we expect to accelerate the commercialization of eco-friendly hydrogen production in the future."
In this study, PhD students Jaeho Byeon and Minkyeong Ban from the KAIST Department of Chemical and Biomolecular Engineering participated as co-first authors. The research findings were published online on May 22, 2026, in Joule, the world's leading academic journal in the energy field, and will be featured in the formal issue of Joule on September 16.
※ Paper Title: Outperforming water electrolysis through catalyst layer structuring with defective 2D mesoporous carbon, DOI: 10.1016/j.joule.2026.102478
※ Author Information: A total of 18 authors including Jaeho Byeon (KAIST, co-first author), Minkyeong Ban (KAIST, co-first author), Liangliang Xu (co-first author), Seunggeon Lee, Seongbeen Kim, Seonggyu Lee, Seongmin Shin, Donghyeok Son, Wonchul Park, Jinkyu Park, Hoyoung Kim, Dongyoon Woo, Seongseop Kim, Dong Young Chung, Jaewook Nam, Jang Yong Lee (Konkuk University, corresponding author), Sungjun Kim (KRICT, corresponding author), and Jinwoo Lee (KAIST, corresponding author).
This research was conducted with support from the National Research Foundation of Korea’s "AEM Water Electrolysis Technology Development" (RS-2024-00467234), the "Nano-Future Materials Source Technology Development" (RS-2023-00235596), the Ministry of Education’s "Ph.D. Student Research Support Project" (RS-2025-25424765), the Korea Research Institute of Chemical Technology (KS2522-10), and the Lotte Chemical Carbon Neutral Center.
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