Shining a light into the ‘‘black box’’ of AI

With no insight into how Al algorithms work or what influences their results, the “black box” nature of AI technology raises important questions over trustworthiness.
Illustration Credit: Gerd Altmann

An international team led by UNIGE, HUG and NUS has developed an innovative method for evaluating AI interpretability methods, with the aim of deciphering the basis of AI reasoning and possible biases.

 Researchers from the University of Geneva (UNIGE), the Geneva University Hospitals (HUG), and the National University of Singapore (NUS) have developed a novel method for evaluating the interpretability of artificial intelligence (AI) technologies, opening the door to greater transparency and trust in AI-driven diagnostic and predictive tools. The innovative approach sheds light on the opaque workings of so-called "black box" AI algorithms, helping users understand what influences the results produced by AI and whether the results can be trusted. This is especially important in situations that have significant impacts on the health and lives of people, such as using AI in medical applications. The research carries particular relevance in the context of the forthcoming European Union Artificial Intelligence Act which aims to regulate the development and use of AI within the EU. The findings have recently been published in the journal Nature Machine Intelligence.

Researchers develop a universal oral COVID-19 vaccine that prevents severe illness in hamsters

Illustration Credit: PIRO

A UCLA-led team has developed an inexpensive, universal oral COVID-19 vaccine that prevented severe respiratory illness and weight loss when tested in hamsters, which are naturally susceptible to SARS-CoV-2. It proved as effective as vaccines administered by injection or intranasally in the research.

If ultimately approved for human use, it could be a weapon against all COVID-19 variants and boost uptake, particularly in low- and middle-income countries, and among those with an aversion to needles.

The study is published in the peer-reviewed journal Microbiology Spectrum.

The oral vaccine is based primarily on the nucleocapsid protein, which is the most abundantly expressed of the virus’s four major structural proteins and evolves at a much slower rate than the frequently mutating spike protein. The vaccine utilizes a highly weakened bacterium to produce the nucleocapsid protein in infected cells as well as the membrane protein, which is another highly abundant viral structural protein.

Recovery of endangered sunflower sea stars may play key role in restoring devastated submarine forests

Sunflower sea stars, such as the one that appears in the foreground, could help keep purple sea urchins in check, according to new research from Florida State University Assistant Professor Daniel Okamoto and colleagues published in Proceedings of the Royal Society B.
Photo Credit: Lynn Lee

Scientists working to understand the decimation of kelp forests on the Pacific Coast have found that the endangered sunflower sea star plays a vital role in maintaining the region’s ecological balance and that sea star recovery efforts could potentially help restore kelp forests as well.

The multi-institution team, which includes Florida State University Assistant Professor of Biological Science Daniel Okamoto, has published a new study showing that a healthy sea star population could keep purple sea urchins — which have contributed to the destruction of kelp forests — in check.

Their work is published in the Proceedings of the Royal Society B.

“Our work is focused on understanding what factors maintain healthy kelp forests as well as healthy urchin populations,” Okamoto said. “That is, what scenarios lead to collapse versus coexistence of these important species.”

‘Neutron camera’ method captures atomic-scale activity in a flash

Artist’s conceptual drawing illustrates the novel energy filtering technique using neutrons that enabled researchers at ORNL to freeze moving germanium telluride atoms in an unblurred image. The images offered key insights into how the material produces its outstanding thermoelectric performance.
Illustration Credit: Jill Hemman/ORNL, U.S. Dept. of Energy

Scientists have long sought to better understand the “local structure” of materials, meaning the arrangement and activities of the neighboring particles around each atom. In crystals, which are used in electronics and many other applications, most of the atoms form highly ordered lattice patterns that repeat. But not all atoms conform to the pattern.

When some atoms take up local arrangements that are different than that implied by the overall structure of the crystal, studying the local structure gets more difficult — especially when the atoms are moving. In fact, the inability to clearly see these local effects means researchers are often not aware they can happen.

Now researchers using the Spallation Neutron Source at Oak Ridge National Laboratory have developed a new method of studying the local structure of materials in detail and in real time.

The team developed a variable-shutter pair distribution function, or vsPDF, technique in which neutrons function like a camera but at timescales that are a trillion times faster.

Uracil found in Ryugu samples

A conceptual image for sampling materials on the asteroid Ryugu containing uracil and niacin by the Hayabusa2 spacecraft
Image Credit: NASA Goddard/JAXA/Dan Gallagher

Samples from the asteroid Ryugu collected by the Hayabusa2 mission contain nitrogenous organic compounds, including the nucleobase uracil, which is a part of RNA.

Researchers have analyzed samples of asteroid Ryugu collected by the Japanese Space Agency’s Hayabusa2 spacecraft and found uracil—one of the informational units that make up RNA, the molecules that contain the instructions for how to build and operate living organisms. Nicotinic acid, also known as Vitamin B3 or niacin, which is an important cofactor for metabolism in living organisms, was also detected in the same samples. 

This discovery by an international team, led by Associate Professor Yasuhiro Oba at Hokkaido University, adds to the evidence that important building blocks for life are created in space and could have been delivered to Earth by meteorites. The findings were published in the journal Nature Communications.

“Scientists have previously found nucleobases and vitamins in certain carbon-rich meteorites, but there was always the question of contamination by exposure to the Earth’s environment,” Oba explained. “Since the Hayabusa2 spacecraft collected two samples directly from asteroid Ryugu and delivered them to Earth in sealed capsules, contamination can be ruled out.”

Purifying water with the power of the sun

A Notre Dame researcher’s invention could improve access to clean water for some of the world’s most vulnerable people.

 “Today, the big challenges are information technology and energy,” says László Forró, the Aurora and Thomas Marquez Professor of Physics of Complex Quantum Matter in the University of Notre Dame's Department of Physics and Astronomy. “But tomorrow, the big challenge will be water.”

The World Health Organization reports that today nearly 2 billion people regularly consume contaminated water. It estimates that by 2025 half of the world’s population could be facing water scarcity. Many of those affected are in rural areas that lack the infrastructure required to run modern water purifiers, while many others are in areas affected by war, natural disasters or pollution. There is a greater need than ever for innovative ways to extend water access to those living without power, sanitation and transportation networks.

Recently, Forró's lab developed just such a solution. They created a water purifier, described in the Nature partner journal Clean Water, that is powered by a resource nearly all of the world’s most vulnerable people have access to: the sun.

New method to identify and explore functional proteoforms and their associations with drug response in childhood acute lymphoblastic leukemia

Rozbeh Jafari, senior researcher at the Department of Oncology-Pathology.
Photo Credit: Courtesy of Rozbeh Jafari

Researchers at the Department of Oncology-Pathology have together with researchers from The European Molecular Biology Laboratory published a paper in Nature Chemical Biology where they developed a method that can identify important differences between proteins in an unbiased way.

The paper examines melting behavior of proteins to define cases where portions of the protein melt differently. In these cases, the method can identify that the protein is likely to exist in multiple physical forms, called proteoforms. Therefore, a new perspective on variations between proteins can be interpreted. The method is applied in the context of childhood acute lymphoblastic leukemia cell lines, and is used to identify specific proteoforms associated with disease biology and drug response. This disease was selected as a proof of principle due to the need for improved precision therapies for patients.

First results from ESO telescopes on the aftermath of DART’s asteroid impact

This series of images, taken with the MUSE instrument on ESO’s Very Large Telescope, shows the evolution of the cloud of debris that was ejected when NASA’s DART spacecraft collided with the asteroid Dimorphos.  The first image was taken on 26 September 2022, just before the impact, and the last one was taken almost one month later on 25 October. Over this period several structures developed: clumps, spirals, and a long tail of dust pushed away by the Sun’s radiation. The white arrow in each panel marks the direction of the Sun.  Dimorphos orbits a larger asteroid called Didymos. The white horizontal bar corresponds to 500 kilometers, but the asteroids are only 1 kilometer apart, so they can’t be discerned in these images.  The background streaks seen here are due to the apparent movement of the background stars during the observations while the telescope was tracking the asteroid pair. 
Full Size Image
Image Credit: ESO/Opitom et al.

Using ESO’s Very Large Telescope (VLT), two teams of astronomers have observed the aftermath of the collision between NASA’s Double Asteroid Redirection Test (DART) spacecraft and the asteroid Dimorphos. The controlled impact was a test of planetary defense, but also gave astronomers a unique opportunity to learn more about the asteroid’s composition from the expelled material.

On 26 September 2022 the DART spacecraft collided with the asteroid Dimorphos in a controlled test of our asteroid deflection capabilities. The impact took place 11 million kilometers away from Earth, close enough to be observed in detail with many telescopes. All four 8.2-metre telescopes of ESO’s VLT in Chile observed the aftermath of the impact, and the first results of these VLT observations have now been published in two papers.

”Asteroids are some of the most basic relics of what all the planets and moons in our Solar System were created from,” says Brian Murphy, a PhD student at the University of Edinburgh in the UK and co-author of one of the studies. Studying the cloud of material ejected after DART’s impact can therefore tell us about how our Solar System formed. “Impacts between asteroids happen naturally, but you never know it in advance,” continues Cyrielle Opitom, an astronomer also at the University of Edinburgh and lead author of one of the articles. “DART is a really great opportunity to study a controlled impact, almost as in a laboratory.”

Surprise from the quantum world

The ferromagnetism of the topological isolator manganese-bismuth-telluride only arises when the atomic structure fails. To do this, some manganese atoms (green) must be moved out of their original position (second green atomic plane from above). Only when there are manganese atoms in all levels with bismuth atoms (gray) is the magnetic orientation of the manganese atoms so contagious that ferromagnetism arises.
Illustration Credit: Jörg Bandmann / ct.qmat

The Würzburg-Dresden Cluster of Excellence ct.qmat has designed a ferromagnetic topological isolator - a milestone on the way to energy-efficient quantum technologies.

As early as 2019, an international research team around the material chemist Anna Isaeva - then junior professor at the Würzburg-Dresden Cluster of Excellence ct.qmat - complexity and topology in quantum materials - succeeded in producing the first antiferromagnetic topological isolator manganese-bismuth-tilluride. (Mn2Te4) a little sensation.

This miracle material no longer needs a strong external magnetic field - it brings its own inner magnetic field with it. This offers the opportunity for new types of electronic components that magnetically encode information and transport it on the surface without resistance. This could make information technology more sustainable and energy-saving in the future, for example. Since then, researchers worldwide have been analyzing different facets of this promising quantum material.

Researchers create exotic quantum light states

The graphic symbolizes how photons are coupled after they have been scattered on an artificial atom - a so-called quantum dot - in a cavity resonator.
Illustration Credit: © University of Basel

Coupled light particles could advance both medical imaging and quantum computing.

Light particles, also called photons, do not normally interact with each other. An international research team has now been able to show for the first time that a few photons can be manipulated in a controlled manner and brought into interaction. This opens up new opportunities in the development of quantum technologies. The results are described by a team from the University of Basel, the University of Sydney and the Ruhr University Bochum in the journal Nature Physics, published online on the 20th. March 2023.

Measure distances and transmit information using light

Photons do not interact with each other in a vacuum; they can fly through each other undisturbed. This makes them valuable for data transfer because information can be transported almost trouble-free at the speed of light. Light is helpful not only for data transmission, but also in certain measuring instruments, because it can be used to determine tiny distances, for example in medical imaging. The sensitivity of such measuring instruments depends on the average number of photons in the system.