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- Natural manifestation: not overweight polar bears and cooling by sound
Natural manifestation: not overweight polar bears and cooling by sound
Norwegian scientists have received unexpected data on polar bears in the Barents Sea: over the past 20-30 years, they have been gradually gaining weight, despite the reduction in ice cover due to global warming. This indicates that the animals have adapted well to the new conditions and switched to prey living on land. Swedish researchers have created a tiny quantum "refrigerator" that uses noise to cool down. Previously, sound vibrations were considered a nuisance and suppressed, but now experts have managed to turn them into an advantage. Read more about these and other discoveries from the world of science in the weekly Izvestia column.
Future doctors will be taught anatomy based on models of their own organs
An innovative scientific School of Applied 3D Anatomy has opened at the Department of Human Anatomy and Histology at Sechenov University. It launches the production of three—dimensional models of bones, joints, muscles, organs, vessels - visual materials that are needed for teaching fundamental disciplines in medicine. The printed copies repeat the natural human anatomy with high accuracy and are as detailed as cadaverous (cadaveric) material, the scientists told Izvestia.
According to them, 3D printing provides unlimited variability in the visualization of individual human organs or systems. As a rule, students, residents, and young doctors get used to working with the same simulator and memorize some typical structure. When they encounter an organ with abnormal development, they can hardly deviate from the template. Thanks to three-dimensional printing, you can print as many personalized options as you want.
— We can print any organ of people of different ages, with all sorts of morphological parameters, individual variability and various pathologies. Both a student, a candidate for an academic degree, and a practicing doctor can take part in this creative process. We are not far from the fact that students will be able to study fundamental disciplines on their own 3D model," Vadim Kornilov, senior lecturer at the department, told Izvestia.
To produce it, you will only need a DICOM file of a computer or magnetic resonance imaging scan of a particular part of the student's body or organ, the teacher specified.
The ice-splitting model will make it cheaper to build ships for the Arctic
MIPT scientists have developed Russia's first physico-mathematical model that realistically predicts how ice breaks upon contact with a ship's hull. This will make it possible to reduce expensive field tests during the construction of icebreakers, calculate accident risks in advance and design more advanced vessels for the Arctic.
— Ice is a complex material. Under load, it behaves like elastic glass, then like plasticine, and then suddenly crumbles. That is, it does not just break, but first deforms and accumulates stress. We have developed an approach that allows us to take these effects into account with high accuracy," said Igor Petrov, Scientific Director of the Department of Computational Physics at MIPT.
Currently, scientists use complex computer calculations based on discrete element methods to model this process. At the same time, existing models are not yet able to fully reflect the complexity of ice behavior: its ability to simultaneously behave like a fragile body, splitting into fragments, and as a plastic material, gradually deforming under pressure.
Drones will mimic the thinking of birds
Researchers from the Institute of Ai at MIPT and Moscow State University have described for the first time the mechanism of thinking of birds, which allows them to distinguish objects with different properties. This natural brain process is much more efficient than its electronic counterparts. Conventional neural networks require supercomputers and terabytes of data for this, while any chicken can quickly learn through trial and error to distinguish, for example, edible from inedible. Scientists will be able to use the architecture discovered by researchers to create robots or drones that will be able to self-learn in the process and perform tasks that were previously accessible only to humans.
A special experiment with ordinary chickens helped the developers understand how birds think. A plexiglass plate with beads of different colors was placed in the experimental chamber. Food was scattered between them, the number of granules of which approximately corresponded to the number of beads. The bird, pecking, had to learn to distinguish edible grains from inedible beads, forming the "inedible" category. With the help of cameras, experts monitored the behavior of birds and analyzed the logic of their decision-making.
— The goal was to determine the moment of category formation in the learning process. The results showed that when presented sequentially, a category is formed, however, the categorization algorithm depends on the order in which the colors are presented. This phenomenon can be related to both the innate functional systems of chickens and their individual experiences," said Ekaterina Diffine, a graduate student at the Lomonosov Moscow State University Faculty of Biology.
The behavior of the birds turned out to be natural: on average, the frequency of errors — pecking on beads instead of food — decreased, and the birds gradually formed a new category of objects — "inedible". Scientists have described this pattern using a mathematical model that allows them to predict the sequence of actions of a bird.
Polar bears in the Barents Sea gain weight
The decreasing Arctic ice cover threatens polar bears by reducing their hunting territories. A team of Norwegian scientists analyzed the relationship between changes in sea ice area and the body fat content of 770 adult polar bears using data from 1995 to 2019. Despite the significant reduction in ice, the animals gained weight on average, which indicates a good adaptation to new conditions. Predators are increasingly switching to land-based prey, including reindeer and seals, whose numbers are growing in warmer environments.
— We can see that polar bears are doing quite well in the current conditions in Svalbard, although they are very different from those that were 20-30 years ago. This does not mean that polar bears will continue to feel good in the future if the sea ice persists," said Jon Aars from the Norwegian Polar Institute in Tromsø.
The study was conducted in the area of the island of Svalbard, located in the Barents Sea, where one of the most extreme losses of sea ice in the Arctic is observed.
The quantum computer was cooled with the help of noise
Quantum computers only work at very low temperatures. However, modern cooling systems also create noise that can interfere with the operation of a fragile system. Researchers at Chalmers University of Technology in Sweden have unveiled a new type of tiny quantum "refrigerator" that uses sound vibrations to control the flow of heat and energy.
Quantum computers built using superconducting circuits must be cooled to temperatures close to absolute zero (about -273°C). Even minor changes, electromagnetic interference, or background noise can quickly erase stored information. In the proposed system, noise is used as a source of cooling force.
— Physicists have long assumed the existence of a phenomenon called Brownian cooling. The idea is that random thermal fluctuations can be used to create a cooling effect. Our work represents the closest implementation of this concept to reality to date," said Simone Gasparinetti, associate professor at Chalmers and senior author of the study.
The refrigerator is based on a superconducting artificial molecule that is connected to several microwave channels. By adding carefully controlled microwave noise in the form of random signal fluctuations in a narrow frequency range, researchers can control the movement of heat and energy in the system with amazing accuracy.
Переведено сервисом «Яндекс Переводчик»
