Январь 2024

Российская наука и мир (по материалам зарубежной электронной прессы)

CONTENTS / ОГЛАВЛЕНИЕ


• One of the most successful scientific collaborations between Russia and the US discovered five elements - and then quietly folded
• Russian physicists test boron carbide as wall coating for ITER reactor
• Testing the gallium anomaly
• New light shed on the Stone Age "invisible wall"
• Study reveals freshwater phytoplankton in Lake Baikal produce sulfur-containing chemical to survive in ice
• Russia completes tests on first wall panels for ITER
• Kira Shingareva : la géographe à l’origine de la cartographie de la face cachée de la Lune
• Cancer mortality in chrysotile miners and millers, Russian Federation: main results (Asbest Chrysotile Cohort Study)
• Academic Star Wars: An analysis of nine excellence initiatives
• Scientists warn missing Russian data causing Arctic climate blind spots
• Astronomers investigate the properties of a peculiar cataclysmic variable
• Des scientifiques russes développent une nouvelle technologie pour réparer les tissus hépatiques

О тридцатилетнем сотрудничестве Ливерморской национальной лаборатории (США) и Объединенного института ядерных исследований (Дубна), в результате которого были открыты пять новых элементов таблицы Менделеева: сверхтяжелые флеровий (114), московий (115), ливерморий (116), теннессин (117) и оганесон (118). Начавшееся в 1989 году по инициативе академика Георгия Флерова и оказавшееся чрезвычайно плодотворным партнерство (в 2010 г. к нему присоединилась Оук-Риджская национальная лаборатория) было приостановлено на неопределенный срок в 2022 г.

I only had a gun pulled on me once during my time at Chemistry World. It was on a chill October morning at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia, and the military guards, still at their post from the Cold War with AK-47s at the ready, hadn’t been told about our cameras. It was only after some hasty negotiation that we were permitted entry and could see the machine - and meet the team - that discovered the five heaviest elements currently known.
It was all thanks to a partnership that had begun almost 30 years earlier, between two former adversaries. ‘It was a special, perhaps unique, long-running collaboration,’ recalls Mark Stoyer, a staff scientist at Lawrence Livermore National Laboratory (LLNL), US, and part of the American team that united with the Russians. It was a collaboration that was ‘extremely scientifically productive and fruitful’, he adds.
Making elements
The reason we went to JINR was Yuri Oganessian - a man who was about to become the only living person with an element named after him. Warm, chuckling, almost grandfatherly, he greeted us in an expansive office, still filled with the drawings of his predecessor as head of JINR’s element discovery team, Georgy Flerov. It had been Flerov, Oganessian explained, that had started the unlikely partnership.
Since the 1940s, element discovery has pushed beyond the elements that exist naturally on Earth. Instead, they are created through nuclear fusion - smashing two atomic nuclei together, to create superheavy, radioactive elements. For 40 years, the US and USSR competed to add to the table, resulting in a stand-off that became known as the ‘transfermium wars’. By the 1980s, a new rival team at GSI Darmstadt in Germany had also started making elements. To gain the advantage once more, Flerov took an unprecedented step. In 1989, while at a conference, he spoke to LLNL scientist Ken Hulet and invited him to work with them. A new Russian-American team had been formed, in direct competition with the team at nearby LBNL.
Flerov died in 1990, but the collaboration blossomed under the leadership of his eventual successor, Oganessian. While the GSI discovered yet more elements, the JINR-LLNL group embraced a new technique, dubbed hot fusion, that would let them reach further. Usually, when nuclei smash together, there is too much energy, and the newly formed nucleus breaks apart in nuclear fission. The Germans used cold fusion, to make elements using as little energy from the accelerator as possible. This was reliable, but as the elements became heavier, the cross section - the probability of success - became smaller.
Hot fusion was different. The accelerator’s power was increased, making the chance of success greater, but fission more likely. To compensate, the team decided to use a beam of calcium-48, an isotope with eight more neutrons than usual. This allowed the newly formed nucleus to jettison the neutrons like a ship’s ballast, reducing the energy and, the team hoped, making the newly formed nucleus more stable.
The first successes
Oganessian’s guided tour of JINR was enlightening. There was, of course, the particle accelerator and its beamlines - a behemoth cyclotron that looked like a giant zinc battery in a clamp. But there were derelict buildings too, and jars of liquid nitrogen with baked bean cans for lids - a sign of constrained funding. Above all, there was a sense of excitement among the scientists: they were expanding the periodic table, seeking discoveries at the very edge of what was possible.
It was a thrill shared by their American counterparts, who I later visited in the warm, wine-growing Livermore valley just outside San Francisco. I met many of the LLNL researchers who travelled to JINR, most notably Stoyer and fellow element discoverer Dawn Shaughnessy. Coming from California, they had been shocked by the realities of Dubna: a town of brutalist architecture and Soviet murals on the banks of the Volga, with a single hotel (allegedly bugged) and no supermarket until a decade ago. Yet JINR had the best particle accelerator for element hunting in the world. Combined with the US team’s cutting-edge data analysis, and their secret weapon of calcium-48, the new elements flowed.
In the late 1990s and early 2000s, their technique had achieved a string of successes: first, elements 114 and 116 - confirmed in 2012, and named flerovium and livermorium to celebrate their historic partnership. Elements 113, 115 and 118 were sighted, too, as we reported in Chemistry World 20 years ago. But element 117 remained elusive. The problem was that, to create the element with calcium-48, the team needed a target made from element 97, berkelium. But there wasn’t any to be had. Large quantities of berkelium could only be produced in two nuclear reactors in the world, and as the element had no use, neither of them made it.
The problem was solved in 2010 at Oak Ridge National Laboratory - the site of the first permanent nuclear reactor, built for the Manhattan Project during the second world war. Still a major research site, Oak Ridge had one of the two reactors, and agreed to isolate enough berkelium for a target while it was producing element 98, californium, for commercial purposes. The JINR-LLNL partnership had gained a third member and element 117 soon followed, later to be named tennessine in honour of Oak Ridge’s home state.
A new rival
In 2015, enough evidence had accumulated that the remaining elements on the eighth row of the periodic table - 113, 115, 117 and 118 - had been made. Yet there was another twist in the tale, which would take me to Wako, a small city on the edge of the Tokyo subway. Outside the station, bronze plaques for each element of the periodic table led me, like a trail of breadcrumbs, to the gates of the Riken research institute. Here, in a surprise coup, a Japanese team had been recognised with the discovery of element 113, using the older cold fusion technique. ‘Discovering an element was a dream from Japan’s history,’ Hideto En’yo, director of Riken’s Nishina Center, told me. ‘A dream to recover from a mistake … for Japan this has been a century-long project.’
The mistake was Masataka Ogawa’s claim to have made element 43, which for several years was known as nipponium before it was struck down. Under the direction of Kosuke Morita, the Japanese team spent a total of nine years trying to find three atoms of element 113 to confirm their discovery, only obtaining enough time with the accelerator after other experiments were shut down in the wake of the Fukushima nuclear incident in 2011. The result paid off - and Japan, and Asia, was recognised with its first element on the periodic table. Unable to use nipponium again as a name, it was instead named nihonium, after nihon, an alternative word for Japan.
Yet Riken’s fillip to Japanese prestige does not subtract from JINR-LLNL’s astonishing achievement. And for many, the collaboration became more than a career highlight: it gave them a unique place in history. Shaughnessy and Stoyer have overtaken Marie Curie as the most successful women to discover elements, both claiming five; at Oak Ridge, Clarice Phelps similarly made history as the first black woman to discover an element - tennessine - an achievement that has catapulted her to appearances on national TV and radio across the US. The city of Livermore has even created Livermorium Plaza in the team’s honour.
Oganessian’s name is also immortalised on the periodic table, along with that of the man who set up the collaboration, as flerovium and oganesson. ‘It’s difficult to say how I feel,’ Oganesson told me, when I asked what it felt like to be the only living person with an element named after him. ‘It was proposed by my collaborators. All of these people who were involved and came to this conclusion … it’s an honour for me, but it’s my friends and colleagues who wanted to express it’. For his team, it is richly deserved. Oganessian is not a principal researcher in the traditional sense; they describe him as the ringmaster of a circus or director of a film - a man whose gifts are creativity and leadership, rather than solely pure science. Despite being in his 90s, he is still searching for more elements.
In 2019, the JINR and LLNL researchers celebrated 30 years of collaboration. They already had plans for yet more elements, too. While calcium-48 couldn’t be used (to make element 119 it would need to be shot into an einsteinium target, an element that has only ever been produced in microgram quantities), they had an alternative. JINR had a new, better machine - the Superheavy Element Factory - which would fire a titanium-50 beam at a californium target made at Oak Ridge, to produce element 120. Success, they predicted, would come within five years.
Fate had other plans.
Going dormant
‘Through no fault of the teams,’ Stoyer says, ‘the Covid-19 pandemic and the political situation [caused by Russia’s invasion of Ukraine] curtailed travel between the countries’. Without the ability to travel, the US and Russians couldn’t collaborate as effectively, and with the breakdown in diplomacy between the east and west, US government laboratories can’t supply the Superheavy Element Factory with the target material. ‘The situation is actually not easy in the current turbulent environment,’ Oganessian told Chemistry World last year. ‘We cannot cooperate with [LLNL] and Oak Ridge because … JINR is located in Russia.’
As suddenly and surprisingly as it began, the JINR-LLNL partnership appears to be over.
Today, the focus for new elements has shifted. Oak Ridge continues to work with Riken, putting the Japanese firmly in the lead for the discovery of element 119 by firing a vanadium beam at curium targets. And, last year, the US government announced plans for a new hunt for element 120, led by JINR’s cold war rivals Lawrence Berkeley - which had abandoned element discovery in the early 2000s - and with support from Oak Ridge and LLNL. It’s here that most in the element-hunting community put their hopes. Other possibilities include GSI Darmstadt once work on a new synchrotron is complete, and a team at the Ganil accelerator in Caen, France.
Yet the legacy of 30-years of shared successes and friendships is unlikely to vanish overnight. ‘I prefer to think of the collaboration as dormant,’ Stoyer says. ‘Collaborative ideas are marinating for when it does become easier to work together again in the future.’
Even if it doesn’t come to pass, though, its legacy is something that none of the researchers, including Stoyer, regret. ‘I can honestly say that I am thankful for the JINR-LLNL collaboration. And especially thankful for the many creative, hard-working and talented individuals involved.’

Специалисты Института ядерной физики им. Г.И.Будкера СО РАН совместно с коллективами других научных организаций проводят испытания карбида бора в качестве покрытия для стенок строящегося во Франции Международного экспериментального термоядерного реактора (ИТЭР). Горение плазмы при термоядерной реакции происходит при экстремально высоких температурах, которые могут повредить стенки реактора, поэтому ведутся исследования по поиску вещества, способного защитить от этого повреждения.

Specialists at the GI Budker Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences (INP SB RAS) together with teams from other scientific organisations are testing boron carbide as a coating for the walls of the International Experimental Thermonuclear Reactor (ITER) under construction in France. Plasma burning during a thermonuclear reaction occurs at extremely high temperatures which can damage the walls of the reactor. Research is underway to find a substance that can protect against this damage.
The plasma in the tokamak is in a toroidal vacuum chamber. Despite the fact that it has little contact with the walls due to the retention of the magnetic field, the load on them is still large. This is both heating and radiation flux emanating from plasma, that is, neutron and gamma radiation. The material of the wall in such conditions can be destroyed. In any case, the wall cover particles will fall into the plasma, but heavy impurities are especially dangerous. Such substances in the plasma lead to its rapid cooling. Finding material for the first wall that would meet all the requirements is very difficult.
Carbon was widely used in research tokamaks to protect the walls, but its use was problematic as it can capture and retain hydrogen isotopes, including radioactive tritium. Currently, tungsten and beryllium are used as material for the first wall of the camera in ITER. Tungsten is refractory and withstands high temperatures well, but it is heavy, and when it enters the plasma, it quickly cools it. Beryllium is very light, and even when it enters the plasma, it does not affect its quality. However, the dust from beryllium is toxic to humans and is a strong carcinogen.
Therefore, a team of scientists led by Anatoly Krasilnikov, head of the ITER centre (Russia’s national agency for the construction of ITER) looked for alternative options for covering the wall of the tokamak. It needed to be heat-resistant and at the same time a light material with high thermal conductivity and electrical conductivity such as some special types of ceramics. Typically, ceramics are an insulator, but there are heat-resistant materials of the ceramic class that have sufficient conductivity.
The study also involves the Lavrentyev Institute of Hydrodynamics SB RAS, Khristianovich Institute of Theoretical & Applied Mechanics (ITAM SB RAS), and Tomsk State University of Management Systems & Radio Electronics. They applied a coating of special material with a thickness of only tens of microns. Tests are being carried out at the BETA installation in INP SB RAS, where the material is subjected to thermonuclear pulse loads. BETA is a material testing complex where it is possible to observe the parameters of the substance directly during the experiment. During testing, the material is submitted to a laser-powered thermal load from the plasma. Using a diagnostic system, temperature, absorbed heat and the degree of erosion can be tracked. Surface damage causes roughness also to change. At the BETA complex, the exact moment erosion begins can be identified with the subsequent loss of matter. "The purpose of the tests was to characterise the limit of the loads that our test materials can withstand during pulsed heating," said research engineer Dmitry Cherepanov.
"We have been developing neutron protection from boron carbide with Virial (St Petersburg) for a long time. Virial company is a manufacturer of equipment components of ceramic and cera-metallic materials. This substance is very durable, has relatively good thermal conductivity, and we test it under the impulse loads that are characteristic of tokamaks," explained researcher Alexander Burdakov.
Boron carbide is similar to light beryllium and does not cause the walls to cool quickly and it is also a readily available material. There are two options for using boron carbide - it can completely replace tungsten or applied to tungsten walls as a protective coating.
So far, the results from testing at the BETA complex show that the threshold values of loads at which ceramics begin to collapse are similar to tungsten. Tests suggest boron carbine is competitive with tungsten carbide and beryllium coatings.

В ходе эксперимента в Баксанской нейтринной обсерватории Института ядерных исследований РАН обнаружились возможные доказательства существования стерильного нейтрино, гипотетической частицы, не взаимодействующей с веществом.

Scientists have confirmed possible evidence of a new elementary particle, the sterile neutrino. These particles, if they exist, interact only via gravity, not any of the other forces in the Standard Model of Particle Physics. The results from the Baksan Experiment on Sterile Transitions (BEST) confirm an anomaly found in earlier solar neutrino source experiments. BEST irradiated a tank of gallium, a soft silvery metal that is liquid at room temperature, using an intense source of neutrinos from decays of radioactive chromium. The neutrinos react in the gallium to produce the isotope germanium 71. This isotope can be extracted from the gallium and counted. The researchers found significantly smaller amounts of germanium than expected based on known nuclear physics. Scientists had found a similar gallium anomaly in a precursor experiment.
The experiment found that the germanium 71 yield was 20% to 24% lower than expected, based on the intensity of the neutrino source and on scientists’ knowledge of how neutrinos are absorbed. These findings are counter to theoretical predictions. However, they are consistent with earlier results on what scientists call the gallium anomaly. The researchers divided the target into inner and outer volumes to search for an indicator of neutrino oscillations. This is a known phenomenon in which an electron neutrino changes into another "flavor," such as a muon neutrino, which results from neutrinos having mass. The researchers did not observe signs of these oscillations. The origin of the anomaly remains a mystery.
BEST is an experiment more than a mile underground in the Baksan Neutrino Observatory in Russia’s Caucasus Mountains. It was designed to explore the deficit of electron neutrinos (ne) previously reported in the four calibration experiments performed by the SAGE and GALLEX solar neutrino collaborations. In this study, researchers used about 47 metric tons of liquid gallium (Ga) metal, divided into two concentric zones, as the target for the absorption of neutrinos via the reaction 71Ga (ne,e)71Ge. They placed the chromium-51 neutrino source at the center of the gallium target, irradiating both zones. As the neutrino path length in each zone is about a meter, BEST has a high sensitivity to oscillations occurring on that scale, corresponding to differences in the square of neutrino masses of about 1 eV2 (a very small amount in the nuclear physics world). The researchers measured the strength of the source by calorimetry and other methods to a precision of better than 1%. The neutrino absorption cross section has a minimum value set by the known electron-capture lifetime of 71-germanium.
The persistence of this anomaly is puzzling. It could indicate either some unidentified experimental artifact that has so far evaded discovery or new physics capable of accounting for an unexpectedly large deficit of neutrinos.
This work is supported by the Department of Energy Office of Science, Office of Nuclear Physics and by the Federal Agency for Scientific Organizations, Ministry of Education and Science of Russian Federation, State Atomic Energy Corporation Rosatom.

Исследовательский коллектив из 21 страны, включая Россию, создал генетическую карту миграций древних людей в Западной Евразии в эпоху голоцена 12000-4000 лет назад. Ученые проследили миграционные маршруты и динамику населения, а также подтвердили существование четкого генетического разделения к востоку и западу от «великого водораздела» - своеобразного культурного барьера, который в течение нескольких тысячелетий простирался через всю Европу от Черного моря до Балтийского и исчез около 4000 лет назад.

Archaeological finds have long pointed to the existence of a kind of barrier, a "great divide" that for long periods stretched up through Europe from the Black Sea in the south to the Baltic Sea region and the Baltic countries during the Stone Age. Analyses of 1600 prehistoric genomes has now shed new light on this invisible wall between different peoples.
During the Stone Age, a kind of invisible wall ran through Europe - a culturally determined dividing line between different peoples who had somewhat different lifestyles, especially when it came to how they subsisted. This dividing line has occupied archaeologists for many years. What were the genetics of the different groups of people living to the east and west of this great divide?
"We were already well aware that such a dividing line existed during the Stone Age and knew that people east of this great divide remained hunters, fishers and gatherers, while those who lived to the west of it over time became pastoralists. That is, until a point in time during the Bronze Age, about 4000 years ago, when this sharp divide began to dissolve. What we did not know was whether these different groups differed genetically. And it turns out that they did according to our analyses of these prehistoric teeth and bone fragments," says Kristian Kristiansen, an archaeologist at the University of Gothenburg and one of the researchers behind the article Population Genomics of Post Glacial Western Eurasia, which is one of four articles recently published in the journal Nature.
Imputation renders older DNA usable
The study contributes crucial new knowledge about the differences in the genetics of hunters, fishers and gatherers in the entire western part of Eurasia. The researchers began preparing the study over ten years ago, and even in the initial phase, it was clear that the oldest DNA samples, up to 11,000 years old, posed a major challenge. The DNA was extremely degraded, but as experience was gained and new technologies emerged when it comes to sampling and extracting DNA, the researchers were soon able to go further back in time with their investigations.
With the aid of imputation, an advanced form of mathematical modelling and based on the analysis of a very large number of modern genomes, the holes in incomplete prehistoric DNA profiles could be filled, rendering these profiles usable and reliable in a wide range of advanced statistical analyses.
Ample food
The researchers already knew about the main genetic traits of three major prehistoric migrations, but many questions remained unanswered. Who were these people? Where did they come from? And to what extent did they interbreed with the local population?
There have been previous theories to explain why the invisible wall through Europe arose. One of them was that people in the area east of this great divide did not engage in agriculture because the continental climate was not well-suited to it, which meant that they stuck to their way of life as hunters, fishers and gatherers.
The climate may have played a role, but the explanation is more complex than that according to Kristian Kristiansen, and points to the culture of the hunters, fishers and gatherers east of the great divide.
"These were very well-organised and sophisticated societies that also included elites such as a warrior class. They had learned how to make pottery and possessed knowledge about food preservation that allowed them to store food. But there was also enough food in the form of fish in the rivers and lakes and game in the forests, so there were no compelling reasons for them to change their lifestyle. In my opinion, that is the main reason why this great divide persisted between these different groups of people. That is, until a new warrior elite west of the divide - from an area between Scandinavia and the Urals - embarked on conquests with horse-drawn chariots about 4000 years ago. These were the contemporary equivalent of modern-day tanks, and the hunters, fishers and gatherers had no chance of defending themselves against them," says Kristiansen.
Genetic mix
Scientists can now show that the Great Divide arose long before the Neolithic, at a time when the peoples on both sides of this line were hunter-gatherers. This discovery raises questions about why the divide existed, since the groups of people on both sides of it had similar lifestyles, and subsisted in the same way. Could the reasons have been cultural or trade-related, for example? This question cannot be answered as yet.
The study shows that the Yamnaya people emerged as a genetic mix between hunters, fishers and gatherers east of the great divide and the people from the Caucasus along the Don River. They lived on the Pontic steppe, now part of present-day Ukraine, southwest Russia and western Kazakhstan, and were the first nomads.
"They had ox-drawn wagons, covered like prairie wagons, and were able to move across the steppe with their animals. While they didn’t develop true agriculture, during their migrations from the Pontic steppe they learned to grow a bit of barley from the local people in eastern Hungary, north of the Carpathians. They took this knowledge with them when they began to migrate more actively towards northwest Europe and Scandinavia, which they reached about 4850 years ago," says Kristian Kristiansen.
They spread at lightning speed
"Their conquest took almost no time at all. The study shows that from the time the Yamnaya people became genetically mixed with people from the Corded Ware culture in Eastern Europe, it took only about 50 years until they had spread out along a distance of almost 900 kms, from the Netherlands to the Limfjord in north-west Denmark," Kristiansen says. "And everywhere they went they burned down forests to be enable their semi-agricultural lifestyle, with a few crops like barley and domesticated animals such as oxen and sheep".
The genetic mixing of the Yamnaya people with the Corded Ware people gave rise to the Single Grave culture in Denmark (which in Sweden is called the Battle Axe culture), and it is largely these people who are the closest ancestors of the Scandinavian peoples alive in Scandinavia and north-western Europe today. Their journey from the Pontic steppe to north-west Europe is mapped in the Nature article titled Population Genomics of Post Glacial Western Eurasia.

Диметилсульфониопропионат (ДМСП) - соединение, синтезируемое морским планктоном для защиты от осмотического давления соленой воды. Однако группа исследователей из Университета Кумамото (Япония) и Лимнологического института РАН обнаружила, что байкальский пресноводный планктон Gymnodinium baicalense, который в осмотической регуляции не нуждается, также вырабатывает ДМСП - в качестве защиты против низких температур в холодное время года.

Dimethylsulfoniopropionate (DMSP) is a compound synthesized by marine phytoplankton for protection against the osmotic pressure of saline water. However, DMSP could also have a role in preventing freezing damage.
Now, in a new study, a group of researchers surveyed Lake Baikal every spring for almost a decade and discovered that freshwater plankton Gymnodinium, which does not need osmotic regulation, produces DMSP as a protective measure against freezing temperatures, suggesting a cryoprotective role of DMSP.
Researchers from Kumamoto University have found that DMSP, a sulfur-containing organic molecule, was produced by freshwater phytoplankton in colder days to help with survival in ice water. Their results revealed a cryoprotectant role for DMSP.
Phytoplankton or microalgae found in the ocean are often known to produce the sulfur-containing chemical DMSP. This organic molecule breaks down to release a strong but sweet-smelling gas called dimethyl sulfide (DMS), which plays a major role in the formation of cloud condensation nuclei and is also associated with the smell of the sea. More importantly, DMSP acts as an osmolyte and thus protects the phytoplankton against the osmotic pressure created by saline water.
Scientists have, however, hypothesized that zwitterionic DMSP - an ion containing both positive and negatively charged functional groups - must also have a role beyond osmotic regulation. Past studies have shown that marine algae in colder oceans produces more DMSP than those found in warmer oceans. In addition, studies have also revealed that the concentration of DMSP in the ocean decreases as the seasonal temperature rises.
Conversely, the abundance of DMSP increases at low temperatures. This could mean that DMSP plays a cryoprotective role for the survival of plankton. In other words, it can act as a substance that protects biological material from damage on being exposed to stresses such as freezing temperatures.
Wanting to decipher the cryoprotective role of DMSP for marine algae, a team of researchers from Kumamoto University and Limnological Institute, Russian Academy of Sciences, led by Professor Kei Toda investigated the presence of DMSP in Lake Baikal in Russia, the world's clearest freshwater lake. Since 2012, the team has been tracking seasonal variations in phytoplankton and DMSP concentration in the ice-covered Lake Baikal.
The results of this decade-long study were recently published in Communications Biology on 24 November 2023. "During one of our previous studies, local people reported DMS-like odors from the lake during the ice-melting season. Pollution was an unlikely source, so the other factor could be the conversion of DMSP by the phytoplankton to DMS. Since freshwater algae do not need osmolytes like their marine counterparts do, this piqued our interest to explore its role further," says Prof. Toda.
The team conducted eight expeditions to the Baikal Lake since 2012 to search for phytoplankton production and analyzing DMSP and related chemicals. To analyze DMSP levels, the researchers dug two ice holes of about 70 cm in diameter in the lake during the spring season (around March). They obtained water samples daily from the surface of the lake and from within the ice colonies where the phytoplankton Gymnodinium baicalense bloomed during spring.
The team found that the Gymnodinium in the ice colonies produced DMSP and released it into the water during the ice-melting season. Their analysis showed that DMSP concentrations were higher on cold days and lower when temperatures were higher than the freezing point.
Phytoplankton use the sulfur atom from the sulfate ions present in seawater to produce DMSP. The results of this study showed that despite the sulfate concentration in Lake Baikal being 1/500th of the concentration found in seawater, the freshwater plankton Gymnodinium effectively used their limited sulfur resource to synthesize DMSP in their cells and survived in freshwater ice.
The observations and the analysis carried out since 2012 validated the role of DMSP as a cryoprotectant for freshwater algae. "Our results can be further verified by culture experiments at different temperatures and by identifying the genes responsible for DMSP production by freshwater algae," says Prof. Toda.
While the production of DMSP by marine plankton for coping with osmotic pressure was known, this study is the first to confirm the production of DMSP by freshwater plankton, which do not require osmotic adjustments.

В НИИ электрофизической аппаратуры им. Д.В.Ефремова (НИИЭФА) завершили испытания прототипа панели первой стенки вакуумной камеры термоядерного реактора ИТЭР, строящегося во Франции.

Manufacturing and testing of prototype first wall panels for the International Thermonuclear Experimental Reactor (ITER) fusion machine has been successfully completed, says St Petersburg-based JSC NIIEFA - part of the Russian state nuclear corporation Rosatom.
The last stage of the multi-year process - from exploratory experiments on small mock-ups to manufacturing and acceptance tests on a full-scale prototype of a highly loaded panel of the first wall of the vacuum chamber of ITER - was measuring the geometric parameters of the prototype after tests.
For the ITER project, which is under construction in Cadarache in southern France, Russia's responsibilities include manufacturing 179 of the most energy intensive (up to 5 MW per square metre) panels of the first wall, which is 40% of the total area of the reactor wall.
Rustam Enikeev, deputy director general for thermonuclear and magnetic technologies at JSC NIIEFA, said: "The next step will be to obtain permission to begin mass production, this will require the preparation and approval of a large volume of documents."
ITER is a major international project to build a tokamak fusion device designed to prove the feasibility of fusion as a large-scale and carbon-free source of energy. The goal of ITER is to operate at 500 MW (for at least 400 seconds continuously) with 50 MW of plasma heating power input. It appears that an additional 300 MW of electricity input may be required in operation. No electricity will be generated at ITER.
Thirty-three nations are currently collaborating to build ITER - the European Union is contributing almost half of the cost of its construction, while the other six members (China, India, Japan, South Korea, Russia and the USA) are contributing equally to the rest. Construction began in 2010. The UK was also involved but in the wake of its departure from the EU it announced in September it was leaving Euroatom. Existing contracts are being honoured but ITER says the UK will not be part of new contracts. Switzerland is currently considered to be a "non-participating third country" as its negotiations with Euratom on an association agreement continues.
According to the ITER website, the first wall panels "are the detachable, front-facing elements of the blanket that are designed to withstand the heat flux from the plasma. These highly technological components are made of beryllium tiles bonded with a copper alloy and 316L (N) stainless steel".
Rosatom says that each panel consists of 40 so-called fingers and the overall dimensions of one panel are 2 metres by 1.5 metres by 0.5 metres, with a weight of about 800 kg. They can be in different shapes, with scientists at JSC NIIEFA developing about 40 design options. It added that NIIEFA specialists "gained unique experience and competencies in the development of the design of plasm-facing components" and the experience would benefit "future national projects in the field of development and creation of plasma-facing components for controlled thermonuclear fusion installations".
Russian record for pulse duration in a tokamak
Meanwhile scientists at the Kurchatov Institute have achieved a discharge with a plasma current of 260 kiloamperes (kA) lasting more than two seconds, a new duration record for tokamaks in Russia. The institute said that temperatures in the plasma in the T-15MD tokamak hit 40 million degrees Celsius during the experiment, which took place on 15 December.

О советском и российском астрономе и планетном картографе Кире Борисовне Шингаревой (1938-2013), одной из первых создавшей атласы обратной стороны Луны, Марса, Фобоса и Венеры и внесшей значительный вклад в разработку планетной номенклатуры. Благодаря ей появилось понятие «география внеземных территорий».

C’est l’une des victimes de l’effet Matilda, cette tendance à invisibiliser les travaux scientifiques féminins : Kira Shingareva revient dans l’actualité avec la multiplication des projets d’alunissage. À l’heure à laquelle la conquête spatiale s’intensifie et s’élargit à de nombreux nouveaux concurrents, cette physicienne russe mériterait de réapparaître sous les radars pour sa cartographie de la "Dark Side of the Moon".
Quand on regarde la Lune, que l’on soit rêveur ou scientifique, ou alors les deux, on voit toujours la même image du sol lunaire. La raison en est simple : la Lune présente toujours la même face à la Terre. Le dessin, dans les grandes lignes, est bien connu des humains depuis la nuit des temps. Mais pendant des années, on ne connaissait pas ce que cachait l’autre côté de la Lune, celui qu’elle ne montre jamais à la Terre ? Ce fut l’un des plus grands mystères de l’humanité. Jusqu’à ce qu’une première carte soit dessinée, en 1967. Une carte qui a fait sensation. Elle a lancé une révolution copernicienne, à l’image des toutes premières cartes du Nouveau Monde fournies par Christophe Colomb, Galilée, Mercator et tant d’autres.
Pourtant, l’Histoire ne retient pas le nom rattaché à la naissance de cette carte de la face cachée de la Lune. Celle qui, dans un travail de fourmi, a patiemment compilé, analysé, mis en image, le tout à la main, les données brutes erratiques transmises par une sonde soviétique de très mauvaise facture, a été totalement oubliée. Son nom ? Kira Shingareva.
Une invisibilité régie par un motif politique mais aussi par pure humilité
Preuve du véritable trou noir qui s’est formé autour de sa personne, Kira Shingareva possède uniquement une page Wikipédia en français à son nom. Aucune trace de biographie sur la célèbre encyclopédie en ligne en anglais, en russe, ou en allemand. Même en cherchant bien, dans toutes les langues, Google et les autres plateformes n’arrivent à aligner qu’une vague biographie administrative, plus ou moins la même dans toutes les langues, avec des noms d’universités, d’institutions diverses. Néanmoins, aucune information n’est affichée sur le contenu de sa carrière. Elle a pourtant travaillé pendant plusieurs décennies dans divers pays du monde, était polyglotte, et à son décès en 2013, internet existait déjà. Il semble pourtant impossible de trouver la moindre vidéo de ses cours ou d’elle-même. Au plus, une unique et mauvaise photo.
Si elle avait été américaine et non pas soviétique, tous les enfants d’Occident connaîtraient son nom, entre Marie Curie et Armstrong, il y aurait des émissions à la télé sur elle, des rues à son nom, on la présenterait comme modèle de femme scientifique aux petites filles. Mais la politique n’explique peut-être pas tout : le moins que l’on puisse dire, c’est que Kira Shingareva n’était pas une influenceuse. Sa passion, ce n’était pas de parler d’elle-même, mais de pratiquer un domaine qui n’existait pas tel quel : la cartographie des corps célestes.
Cette discipline a permis l’émergence de cartes comme celle de Phobos, l’une des lunes de Mars, un corps céleste de forme étrange, avec d’inquiétants cratères. Aucune signature ne figure sur cette carte. Pourtant, le tracé de la carte de Phobos avait été fait de la main de Kira Shingareva, puis plagié par les autres. On retrouve néanmoins son nom, aux côtés d’autres scientifiques, sur l’Atlas des planètes terrestres et de leurs lunes, publié en 1992. Autres marques de reconnaissance de son travail : un astéroïde et un cratère lunaire portent son nom et son prénom.
Kira Shingareva : la pionnière de la cartographie des corps célestes
Il y a une étrange leçon scientifique dans cette histoire : on croit que la recherche est une question de laboratoires bien structurés et bien dotés financièrement, alors que les découvertes sont le fait de personnages singuliers que tout le monde se presse d’éliminer.
Pour l’heure, on connaît peu de choses sur la vie de Kira Shingareva, ni sa réaction lorsque ses travaux ont été pillés par tous, et qu’elle avait été reléguée dans les poubelles de l’Histoire. En tout cas, elle avait pu s’adonner à la grande passion de la vie, un domaine qu’elle a créé, celui de la cartographie des corps célestes. Avec sans doute cette pensée des plus troublantes : qu’elle restera pour toujours la première de toute l’histoire humaine à avoir vu l’autre face de la Lune.
L’autre face de la Lune, tout comme il y a une autre autre face, tellement discrète, de l’humanité, celle des petites gens bizarres qui pourtant contribuent à illuminer l’autre.

Исследовательская группа ученых Международного агентства по изучению рака (IARC), Научно-исследовательского института медицины труда имени Н.Ф.Измерова, Екатеринбургского медицинского научного центра профилактики и охраны здоровья работников промышленных предприятий и Института наук об оценке риска Утрехтского университета (Нидерланды) опубликовала результаты когортного исследования смертности среди рабочих крупнейшего в мире месторождения хризотилового асбеста в городе Асбест Свердловской области. В основу исследования легли данные 30445 сотрудников, проработавших не менее года в период с 1975 по 2010 гг. Исследование показало, что асбестовая пыль заметно увеличивает риск развития рака легких и мезотелиомы у мужчин, но на женщин оказывает меньшее влияние даже в случаях значительного и продолжительного воздействия.

An international research group of scientists from the International Agency for Research on Cancer (IARC), the Izmerov Research Institute of Occupational Health (IRIOH) in Moscow (Russian Federation), the Yekaterinburg Medical Research Center for Prophylaxis and Health Protection in Industrial Workers (Russian Federation), and the Institute for Risk Assessment Sciences, University of Utrecht (The Netherlands) reports the main results on cancer mortality from a historical cohort study of workers employed in the world’s largest chrysotile (asbestos) mine and its enrichment factories located in the town of Asbest, Sverdlovsk Oblast, Russian Federation. These results were published today in the Journal of the National Cancer Institute.
The study was based on company employment records of all workers who had, after 1975, worked for at least 1 year in any enterprise of the mine or its factories; all of those enterprises had systematic stationary dust measurement surveillance. The cohort includes 30 445 workers (32% women), of whom 54% had worked for more than 30 years in the mine or enrichment factories. Cohort members were followed up for vital status and cause of death until 2015.
Mesothelioma mortality was strongly increased with higher cumulative exposure levels, based on 13 deaths from this cause overall; none of those deaths occurred among workers in the lowest exposure category. There was increasing mortality from lung cancer in men with increasing cumulative exposure, with a 40% higher risk of dying from lung cancer in the highest percentile of cumulative exposure. In women, based on much smaller numbers of deaths from lung cancer, the association was less strong. Inconsistent associations were seen between cumulative exposure and mortality from colorectal cancer and stomach cancer. No increased mortality was seen for laryngeal cancer or ovarian cancer.
The study confirms that exposure to dust containing chrysotile mined in the world’s largest active asbestos mine increases the risk of developing cancer in a dose-dependent manner. This was confirmed for mesothelioma and for lung cancer. For lung cancer, it suggests an interplay with other lung carcinogens, especially tobacco smoking, and perhaps also with other occupational exposures, which may be why the increased risk was clearer in men and at lower exposure levels than in women.
The unique feature of the study is the reconstruction of past exposures to dust for every individual worker, by linking the wealth of information of almost 100 000 dust measurements carried out over more than six decades with the detailed occupational history of workers from their employment records of when and exactly where each worker worked in the mine or factories. Also, based on parallel dust and fibre measurements, cumulative exposure to chrysotile fibres could be estimated. Access to the original death certificates enabled a unified classification of causes of death according to international guidelines using the most up-to-date medical classification of disease. Limitations are inherent in the epidemiological study design of an archive-based approach with no personal contact with workers.

Авторы рассматривают опыт девяти стран в инициативах академического превосходства (academic excellence initiatives) - государственных программ по дополнительному финансированию отдельных университетов с целью повышения их продуктивности и продвижения в мировых рейтингах. В России такой инициативой стал проект 5-100. Статья подготовлена по материалам книги «Академические "Звездные войны": инициативы превосходства в глобальной перспективе». Книга вышла в издательстве Массачусетского технологического института в декабре 2023 г. и находится в открытом доступе.

By the beginning of the 21st century it was clear that the combination of massification of enrolments in higher education and the globalisation of science was creating fundamental change in higher education worldwide. Differentiation of academic institutions to serve diverse needs, internationalisation and the importance of research were among the key requirements of academe.
To achieve these, and other goals, a small number of countries, perhaps a dozen or more, engaged in large-scale government-funded academic excellence initiatives (AEIs) to quickly induce change, and more specifically to boost research productivity and a culture of research in their top universities as well as to foster other reforms.
Not unrelated was the rise of global rankings which also stimulated competition among top universities. The Russian government titled its effort Project 5-100 and aimed to get five Russian universities into the top 100 in the global rankings. It failed to get even one into the top league.
To understand this important phenomenon our newly published book, Academic Star Wars: Excellence initiatives in global perspective (also available free in open access), analysed excellence initiatives in nine countries.
A European and Asian phenomenon
There are perhaps 1,200 research universities out of a total of 25,000 universities all over the world - clearly a small minority. AEIs, in turn, focus only on a small subset of this elite sector of global higher education. However, changes in this sector may have a profound effect on the global higher education system and deserve special attention.
Our nine cases spent perhaps US$100 billion over a period of more than a decade. At least half that amount was spent in one country, China, which also had dramatic success in boosting its research university sector and, not coincidentally, its position in the rankings.
The goals, scope, funding and success, or failure, of the initiatives vary considerably. And our cases show a variety of serendipitous positive results as well. It is perhaps significant that there were no AEIs in the Anglophone world, and none in the Western Hemisphere or in Africa. These initiatives are a European and Asian phenomenon. It is worth looking at some of the key general findings from our nine cases.
Excellence that ends up in rankings
Governments throughout the world increasingly acknowledge the role of universities in supporting knowledge-based economies. Universities are universally recognised for their role in educating scientists and professionals and producing research for societies that are increasingly part of a global economy. Although globalisation is a controversial concept in many countries, it is an inevitable dimension - and AEIs are a key strategic element of it.
The Russian 5-100 initiative was not unique in concretely mentioning rankings as part of the aims of the programme. In Japan, then prime minister Shinzo Abe declared in 2013 his policy to have 10 Japanese universities rank in the top 100 in the world by 2023 as a symbolic indicator of the recovery of Japan’s economy and society.
Similarly, in France, the AEI was very much a reaction to the lack of visibility of French research in the international rankings. Even the German AEI is often associated with the ‘Shanghai shock’ - linked to the fact that no German university was represented in the top 50 in either the Shanghai Ranking of 2003 or the Times Higher Education World University Rankings of 2004.
Because of the focus on rankings, the parameters used by them loom large in the goals and foci of national AEIs. ‘Rankings consciousness’ is central to many, if not most of the AEIs. While many in the academic community are sceptical about the relevance of rankings as a major metric for measuring excellence, policy-makers and the public almost without exception see these rankings as a key sign of success and a justification for allocating resources to AEIs.
Our own view is that there has been too much emphasis on rankings when shaping AEIs in general, and that these initiatives benefit most when they focus on national and institutional goals and limit the use of rankings and other measures to the role of benchmarks for comparison with other institutions and countries.
Internationalisation
Internationalisation is considered the main element of all AEIs. Their design often assumes a direct push towards international cooperation, global visibility and mobility - and provides incentives for institutions and individuals.
Internationalisation has two main aspects. The most relevant for AEIs is the internationalisation of research through jointly authored articles and research projects and the mobility of graduate students, professors and researchers. These are all signs of the internationalisation of science and scholarship, and thus it is not surprising that AEIs everywhere have stressed the importance of internationalisation.
In some countries, such as Japan, internationalisation is a challenge due to language, traditions and other barriers. Progress in internationalisation is often measured by clear quantitative indicators, such as the number of joint articles or proportion of foreign academics and students.
In South Korea, however, due to limited financial resources, most universities have focused on internationalisation at home and short-term overseas experiences for graduate students rather than spending large amounts on recruiting international scholars and students.
Specifically, they have used as quantitative indicators of internationalisation the proportion of courses, programmes and dissertations in English, the number of intensive short-term seminars taught by foreign scholars and the number of presentations at international conferences. Similar ‘adjustment’ techniques were used by the Russian 5-100 participating universities.
Governance and role of government
In most AEI programmes, the government plays a key role not just as a source of funding but also because it defines the goals and the rules of the game. Governments require universities to be more accountable, thus making them directly subordinate to government agencies. As the Danish government put it in 2006: "Universities that are doing well should be rewarded. And poor quality should have consequences."
Such direct government involvement has raised concerns in most AEIs. The Taiwanese case shows that it has likely diluted social trust and raised anxiety in the university community.
This reinforces a situation in which the definition of excellence is translated into simple indicators, such as positions in the global university rankings that demonstrate impact, quality and performance. Malaysia, Japan and Russia are clear examples of a rather top-down approach to programme implementation.
At the same time, with the government playing the key role, AEIs do not in most cases increase substantially the involvement of industry in higher education and do not help universities to become more financially sustainable. This correlates with the fact that governance models have not changed much, reflecting a hierarchical relationship between university and government.
Impact
Evidence suggests that AEIs have had a substantial impact on the performance of beneficiary universities, increasing their efficiency, research output, competitiveness and global visibility.
They also affect the allocation and concentration of talent - of faculty and students alike. Furthermore, AEIs have also had a positive effect on other universities and national research systems in general.
AEIs have increased academic mobility and created more opportunities for early career researchers. Less measurable are the soft but perhaps equally important effects of AEIs. These include a greater drive for excellence, a stronger competitive spirit and the increasing role of leading universities in national and regional development.
While the cases in Academic Star Wars indicate a positive impact of AEIs overall, some less favourable side effects have also emerged. For example, it is well documented that the short-term goals associated with some programmes force universities to concentrate on quick-to-publish areas and journals and to redirect their priorities and disciplinary profiles to better fit the global rankings.
Significant concerns
Our analysis has revealed a number of additional concerns. First, some case studies clearly state that it is doubtful that these changes are sustainable without permanent funding. Another is a tension between local and global values (since the world-class model is associated with the US model of a research university).
Reaching high positions in the rankings may mean becoming more similar to Western higher education systems and institutions, especially in terms of resources, standards, performance indicators and organisational or governance patterns. The Taiwan, Japan and China case studies raise concerns about this aspect.
Another issue relates to academic freedom. Does participation in AEIs bring more autonomy and academic freedom? In China and Russia, it seems that participation in AEIs brought more institutional autonomy on matters relating to teaching, research and staffing. At the same time, the government continues to control key aspects and exercise increasing control, especially in the humanities and social sciences which were largely ignored in most AEIs.
There is also a concern in some countries that the concentration of resources in a small number of universities will starve the rest of the national higher education system. Regional inequalities have also been noted in France, Russia and South Korea, with metropolitan universities getting most of the additional funding.
The Taiwan case study showed a weak connection between universities and local communities in the pursuit of academic excellence. In Germany, the autonomy of academic units has also created tensions between centres of excellence benefiting from the excellence initiative and those not involved.
These are all areas that we highlight in the book and which merit extra attention.

В России расположены 17 из 77 станций международной сети INTERACT, занимающейся исследованиями Арктики, в том числе климатическим мониторингом. Потеря данных с этих станций и последующие информационные пробелы могут иметь серьезные последствия для отслеживания и прогнозирования изменения климата не только в быстро нагревающейся Арктике, но и во всем мире.

Loss of scientific data from Russia's Arctic monitoring stations following the invasion of Ukraine has worsened information gaps that could have serious implications for tracking and predicting climate change globally, researchers warned Monday.
The Arctic is warming between two and four times faster than the rest of the planet and holds glaciers, forests and carbon-rich frozen soils at risk of irreversible change that could reverberate across the planet. Monitoring relies heavily on data from stations spread across the vast and diverse region, but Moscow's assault on Ukraine in February 2022 triggered a freeze in scientific cooperation in the Arctic - and elsewhere.
Russia represents almost half the landmass of the entire Arctic region, creating a massive information gap, said lead author Efren Lopez-Blanco, of Aarhus University, who led the study published in Nature Climate Change. Researchers sought to quantify just how much of an impact this has had on scientific understanding of the changes taking place in the Arctic.
"One of the immediate issues that arises if we neglect the Russian boreal forest is that we have an underestimation of biomass, soil organic carbon," Lopez-Blanco told AFP. "This has potentially global consequences for important processes such as permafrost thawing, shifts in biodiversity, or even greenhouse gas emissions."
Sharing problems
The researchers focused on around 60 research stations making up part of a large territorial network called INTERACT. Using computer models, they looked at eight factors - including air temperature, rainfall, snow depth, vegetation biomass and soil carbon - and found that even before the conflict in Ukraine the network had gaps, with stations concentrated in warmer, wetter areas, leaving other areas under-represented. Without Russia, which accounts for 17 of the 60 stations, this bias increased, with the loss of areas such as Siberia's huge taiga forest.
The research highlights the logistical challenges of monitoring such a vast and often inhospitable region, as well as inherent problems with voluntary data sharing. As a result, projects have been delayed or cancelled, while the regional Arctic Council forum - long held up as a model of cooperation - is now divided between the West (Canada, Denmark, Finland, Iceland, Norway, Sweden and the United States) and Russia.
Dmitry Streletskiy, a researcher at George Washington University, who was not involved in the paper and whose work on permafrost uses another monitoring group, CALM, said of nearly 80 Russian sites registered in their network, around 55 normally share data every year. But so far, only 37 have provided 2023 data, he said, although some may send information later. One solution, he said, would be to treat key climate metrics the same way weather data is, and have a United Nations system to ensure continuous monitoring. Streletskiy said data is being collected but not shared, potentially leading to gaps in global understanding.
"It's like these big communal apartments. You have a lot of rooms, and some neighbors are nice, some are not," he said. "But if you aren't aware that your neighbor has a room with a leaking roof, you will only find out when the entire house is flooded. That's pretty much what's happening."

Астрономы из Турции и России провели оптические наблюдения поляра или магнитной катаклизмической переменной, известной как SRGA J213151.5+491400 и обнаруженной в 2020 году. Катаклизмические переменные - двойные звездные системы, состоящие из первичного белого карлика и обычной звезды-компаньона, от которой белый карлик притягивает вещество. Такие системы неравномерно увеличивают яркость, а затем снова возвращаются в состояние покоя. Поляры же отличаются наличием у белых карликов очень сильного магнитного поля.

Astronomers from Turkey and Russia have performed optical observations of a magnetic cataclysmic variable known as SRGA J213151.5+491400. Results of the observational campaign, presented Jan. 11 on the pre-print server arXiv, yield important insights into the properties of this peculiar system.
Cataclysmic variables (CVs) are binary star systems consisting of a white dwarf primary that is accreting matter from a normal star companion. They irregularly increase in brightness by a large factor, then drop back down to a quiescent state. These binaries have been found in many environments, such as the center of the Milky Way galaxy, the solar neighborhood, and within open and globular clusters.
Polars are a subclass of cataclysmic variables distinguished from other CVs by the presence of a very strong magnetic field in their white dwarfs. One of them is SRGA J213151.5+491400, which was first identified in 2020 as an X-ray source, when it experienced a prominent flare.
A team of astronomers led by Solen Balman of the Istanbul University, Turkey, began to observe SRGA J213151.5+491400 in the optical wavelengths, shortly after its flaring activity started. For this purpose, they used the TÜBITAK National Observatory in Turkey and the Special Astrophysical Observatory (SAO) in Russia.
"In order to identify and study the source we used observations with the optical telescopes at TUG (TÜBITAK National Observatory, Turkey) - mainly RTT150 1.5m telescope and at the SAO RAS (Special Astrophysical Observatory, Russian Academy of Sciences) - mainly 6m telescope (BTA)," the researchers wrote.
Observations conducted by Balman's team show that SRGA J213151.5+491400 changed to a low state at the beginning of 2021 from the high state in 2020 with a decrease of 3.0 mag in brightness. The spin pulse profile of the source was found to be single peaked (mostly sinusoidal) in the high state, while during the low state a double-peaked profile was seen, indicating a two-pole accretor.
The astronomers underlined that change of accretion geometry and pole-switching from one to two-pole accretion within or across states is detected in several polar magnetic cataclysmic variables.
Based on the collected data, the spin period of the white dwarf in SRGA J213151.5+491400 was measured to be approximately 85.98 minutes. This is one of the shortest spin periods obtained for polar-type systems.
Low-resolution spectroscopy performed by the researchers revealed prominent Balmer lines and a helium line. It was noted that the Doppler tomography using these spectral lines confirmed the polar nature of this system.
The authors of the paper added that additional observations of SRGA J213151.5+491400 in X-rays, using the Neutron Star Interior Composition ExploreR (NICER) identified the soft X-ray component in the low state. Therefore, this is the first detection of a soft component in the low state of a polar.

Исследователи Российского химико-технологического университета им. Д.И.Менделеева разрабатывают технологию восстановления поврежденной в результате цирроза ткани печени. Поврежденные участки заменяются специальной клеточной структурой, изготовленной на 3D-принтере из биополимерного аэрогеля. Имплант стимулирует регенерацию собственных тканей организма, после чего постепенно рассасывается.

Des chercheurs de l'Université de technologie chimique Dmitri-Mendeleïev de Moscou développent une nouvelle technologie permettant de restaurer les tissus hépatiques endommagés à la suite d'une cirrhose.
La méthode consiste à remplacer le tissu hépatique endommagé par une structure cellulaire spéciale qui stimule la régénération des propres tissus du corps. L'implant sera fabriqué individuellement pour chaque patient à l'aide d'une imprimante 3D sur une matrice composée d'aérogel, un matériau poreux spécial obtenu à partir de biopolymères. Le tissu obtenu sera ensuite traité avec des antibiotiques anti-inflammatoires et les cellules souches du patient pour accélérer le processus de guérison.
«Nous développons une approche qui permettra de cultiver un certain tissu à l'extérieur du corps, d'assurer la fusion des tissus lors du processus de transplantation, d'accélérer les processus de régénération et de restaurer les fonctions de l'organe», a indiqué, dans un communiqué, Pavel Tsygankov, chef de projet et chercheur principal à l'université de technologie chimique.
«L'aérogel se dégrade progressivement sans nuire à notre corps, les cellules se multiplient progressivement et des tissus sains se forment», a expliqué Andreï Abramov, chercheur junior à l'Université.
En dépit des résultats prometteurs, il faudra plusieurs années pour introduire cette méthode dans la pratique médicale, car un cycle complet d'études précliniques et cliniques par les développeurs est nécessaire. Cependant, les scientifiques affirment qu'à l’avenir, cette approche pourrait être utilisée pour réparer non seulement le foie, mais également d’autres organes.

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