Май 2023 г.

Российская наука и мир (по материалам зарубежной электронной прессы)

CONTENTS / ОГЛАВЛЕНИЕ


• Prehistoric pendant’s DNA reveals the person who held it
• New tusk-analysis techniques reveal surging testosterone in male woolly mammoths
• "We are cut off". Tensions with Russia are hobbling Arctic research
• Chemists find that metal atoms play key role in fine organic synthesis
• What Russia’s continued participation in the ISS means for science
• Research shows genetically modified plants grow better in arid and saline conditions
• Russie: Les glaciers du Tchouïa du Nord ont diminué de moitié
• Un nouveau pas en direction des supraconducteurs en conditions ambiantes
• Indian scholars in Sanskrit and Pali can do a lot to support Buddhism in Russia - Russian Buddhist scholar
• The origin of butterflies: A 100 million-year-old mystery unraveled
• Russian ship to take scientists on voyage to study Vietnam's sea
• Reading comprehension not worsened by noise, study finds
• If you’re going to visit Venus, why not include an asteroid flyby too?

Международной группе палеогенетиков из девяти стран, в том числе России (ИАиЭ СО РАН) удалось выделить из древней подвески, сделанной из оленьего зуба, ДНК владелицы украшения - женщины, жившей в Денисовой пещере примерно 19-25 тысяч лет назад. Для этого впервые использовался специальный метод извлечения ДНК из пористого материала, не повреждающий сам артефакт. Помогло и то, что нашедшие подвеску в 2019 г. российские археологи сумели извлечь и сохранить ее так, чтобы избежать загрязнения современной ДНК.

Even Stone Age humans enjoyed the finer things in life, such as animal-tooth jewellery. Capitalizing on ancient fashions, scientists have extracted DNA from a 20,000-year-old deer-tooth pendant to identify the person who presumably either made or wore the ornament - a woman of north Eurasian ancestry.
To do so, the team developed an elaborate process to extract DNA from the tooth without damaging the priceless specimen. The pendant was unearthed in Denisova Cave in Siberia, Russia, which was occupied by various species of hominin over 300,000 years. The study was published in Nature today.
"It’s almost like you open a time travel machine," says study co-author Elena Essel, a molecular biologist who works on ancient DNA at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. "With each sample we are able to learn a bit more and make more inferences about how these people lived."
Unidentified objects
An animal’s genetic material is stored deep within the pores of its bones and teeth. Artefacts that were extensively touched, such as a necklace pendant, can also carry the DNA of the person who handled them in the deep past. Previously, it was impossible to associate tools and jewellery with those who handled them unless the artefact was found near a specific burial.
Essel and her colleagues coaxed DNA from inside the pores of the ancient pendant by soaking it in increasingly warm salt solution, which they found did not alter the pendant. Once released, the small amounts of genetic material were sequenced and compared with other sets of ancient DNA.
Mitochondrial DNA - which is handed down from mother to offspring - extracted from the pendant show that the object is roughly 19,000 to 25,000 years old and that the tooth belonged to a wapiti, also known as an elk (Cervus canadensis). Analysis of nuclear DNA from the ornament suggests that it had been made or worn by a female Homo sapiens whose genetic make-up resembles that of north Eurasian individuals who lived around the same time but were previously known only from remains found farther east in Siberia.
Study co-author Elena Zavala, a geneticist now at the University of California, Berkeley, says that the technique can connect ancient humans to "the tools that they created" - but, unlike other methods, does not destroy the artefact.
However, there are a number of drawbacks to the method. Modern DNA can easily contaminate an artefact, making analysis difficult. And even for the cleanest specimens, the DNA-extraction method is time-consuming, requires sophisticated technology and must be performed in a specialized laboratory. Essel and her colleagues are working to streamline their process. In the meantime, archaeologists can minimize contamination by wearing gloves and a face mask, and by immediately popping specimens into a refrigerator.
Still, Ludovic Orlando, a molecular archaeologist at the University Paul Sabatier in Toulouse, France, who was not involved in the study, was impressed by the thoughtfulness and efficiency of the team’s procedure. The technique is not "a magic bullet", says Orlando. But it still provides "a signature from nothing, from a piece of bone or tooth", he adds. "You see the population signature of the people who interacted with the animal."
Essel finds it comforting that humans living so long ago took the time and effort to make jewellery to adorn themselves. "It’s so special for humankind that despite all odds, you have the hardest life on Earth, but you still try to seek the beauty in life."

Международная группа палеонтологов, в том числе российских, исследовала химический состав дентина в бивнях шерстистого мамонта возрастом около 35000 лет и сравнила его с данными африканского слона. Анализ колебаний уровня накопленного в зубной ткани тестостерона подтвердил предположение ученых о том, что самцы мамонтов испытывали муст - периодические вспышки неконтролируемой агрессии на фоне скачков гормонального фона, характерные для современных слонов.

Traces of sex hormones extracted from a woolly mammoth’s tusk provide the first direct evidence that adult males experienced musth, a testosterone-driven episode of heightened aggression against rival males, according to a new University of Michigan-led study.
In male elephants, elevated testosterone during musth was previously recognized from blood and urine tests. Musth battles in extinct relatives of modern elephants have been inferred from skeletal injuries, broken tusk tips and other indirect lines of evidence. But the new study, scheduled for online publication May 3 in the journal Nature, is the first to show that testosterone levels are recorded in the growth layers of mammoth and elephant tusks. The U-M researchers and their international colleagues report annually recurring testosterone surges - up to 10 times higher than baseline levels - within a permafrost-preserved woolly mammoth tusk from Siberia. The adult male mammoth lived more than 33,000 years ago. The testosterone surges seen in the mammoth tusk are consistent with musth-related testosterone peaks the researchers observed in an African bull elephant tusk, according to the study authors. The word "musth" comes from the Hindi and Urdu word for intoxicated.
"Temporal patterns of testosterone preserved in fossil tusks show that, like modern elephants, mature bull mammoths experienced musth," said study lead author Michael Cherney, a research affiliate at the U-M Museum of Paleontology and a research fellow at the U-M Medical School.
The study demonstrates that both modern and ancient tusks hold traces of testosterone and other steroid hormones. These chemical compounds are incorporated into dentin, the mineralized tissue that makes up the interior portion of all teeth (tusks are elongated upper incisor teeth).
"This study establishes dentin as a useful repository for some hormones and sets the stage for further advances in the developing field of paleoendocrinology," Cherney said. "In addition to broad applications in zoology and paleontology, tooth-hormone records could support medical, forensic and archaeological studies."
Hormones are signaling molecules that help regulate physiology and behavior. Testosterone is the main sex hormone in male vertebrates and is part of the steroid group of hormones. It circulates in the bloodstream and accumulates in various tissues. Scientists have previously analyzed steroid hormones present in human and animal hair, nails, bones and teeth, in both modern and ancient contexts. But the significance and value of such hormone records have been the subject of ongoing scrutiny and debate. The authors of the new Nature study say their findings should help change that by demonstrating that steroid records in teeth can provide meaningful biological information that sometimes persists for thousands of years.
"Tusks hold particular promise for reconstructing aspects of mammoth life history because they preserve a record of growth in layers of dentin that form throughout an individual’s life," said study co-author Daniel Fisher, a curator at the U-M Museum of Paleontology and professor in the Department of Earth and Environmental Sciences.
"Because musth is associated with dramatically elevated testosterone in modern elephants, it provides a starting point for assessing the feasibility of using hormones preserved in tusk growth records to investigate temporal changes in endocrine physiology," said Fisher, who is also a professor in the U-M Department of Ecology and Evolutionary Biology.
For the study, researchers sampled tusks from one adult African bull elephant and two adult woolly mammoths - a male and a female - from Siberia. The samples were obtained in accordance with relevant laws and with appropriate permits. The researchers used CT scans to identify annual growth increments within the tusks. A tiny drill bit, operated under a microscope and moved across a block of dentin using computer-actuated stepper motors, was used to grind contiguous half-millimeter-wide samples representing approximately monthly intervals of dentin growth. The powder produced during this milling process was collected and chemically analyzed.
The study required new methods, developed in the laboratory of U-M endocrinologist and study co-author Rich Auchus, to extract steroids from tusk dentin for measurement with a mass spectrometer, an instrument that identifies chemical substances by sorting ions according to their mass and charge.
"We had developed steroid mass spectrometry methods for human blood and saliva samples, and we have used them extensively for clinical research studies. But never in a million years did I imagine that we would be using these techniques to explore ‘paleoendocrinology,'" said Auchus, professor of internal medicine and pharmacology at the U-M Medical School.
"We did have to modify the method some, because those tusk powders were the dirtiest samples we ever analyzed. When Mike (Cherney) showed me the data from the elephant tusks, I was flabbergasted. Then we saw the same patterns in the mammoth - wow!"
The African bull elephant is believed to have been 30 to 40 years old when it was killed by a hunter in Botswana in 1963. According to estimates based on growth layers in its tusk, the male woolly mammoth lived to be about 55 years old. Its right tusk was discovered by a diamond-mining company in Siberia in 2007. Radiocarbon dating revealed that the animal lived 33,291 to 38,866 years ago.
The tusk from the female woolly mammoth was discovered on Wrangel Island, which was connected to northeast Siberia in glacial periods of lower sea level but is now separated from it by the Arctic Ocean. Carbon-dating showed an age of 5,597 to 5,885 years before present. (Wrangel Island is the last known place where woolly mammoths survived, until around 4,000 years ago.)
In contrast to the male tusks, testosterone levels from the female woolly mammoth tusk showed little variation over time - as expected - and the average testosterone level was lower than the lowest values in the male mammoth’s tusk records.
"With reliable results for some steroids from samples as small as 5 mg of dentin, these methods could be used to investigate records of organisms with smaller teeth, including humans and other hominids," the authors wrote. "Endocrine records in modern and ancient dentin provide a new approach to investigating reproductive ecology, life history, population dynamics, disease, and behavior in modern and prehistoric contexts."
In addition to Cherney, Fisher and Auchus, the authors of the Nature study are Adam Rountrey and Scott Beld of the U-M Museum of Paleontology; Perrin Selcer of the U-M Department of History and the Program in the Environment; Ethan Shirley of the U-M Museum of Paleontology and the Department of Earth and Environmental Sciences; Bernard Buigues of Mammuthus, France; Dick Mol of the Natural History Museum in Rotterdam, Netherlands; Gennady Boeskorov of the Siberian Branch of the Russian Academy of Sciences; Sergey Vartanyan of the Far-East Branch of the Russian Academy of Sciences; and Alexei Tikhonov of the Russian Academy of Sciences and North-Eastern Federal University in Yakutsk, Russia.
Tusk specimens were CT scanned using laboratories at the U-M School of Dentistry, Ford Motor Co., U-M Department of Earth and Environmental Sciences, and U-M Orthopaedic Research Laboratories. The study received support from U-M’s seed funding program for innovative interdepartmental collaborations, Mcubed 3.0.
"This is one of the reasons we come to work every morning at the University of Michigan: to make discoveries that empower us to see the world in new ways," co-author Selcer said. "The project shows you the importance of both collaboration across schools - thanks to Mcubed 3.0 - and of the university’s instrumentation infrastructure."

Напряженность в отношениях с Россией мешает международным исследованиям в Арктике, ставит под угрозу программы по мониторингу климатических данных, исследования по океанографии и экологии. Отдельные исследователи и организации пытаются сохранить контакты, но это лишь малая часть прошлого сотрудничества.

In 2010, Russian President Vladimir Putin - then the prime minister - visited a remote research station on Samoylov Island, in Siberia’s far north. Beginning in the 1990s, the facility on the Lena River had become a hub for German and Russian collaboration on change in the region’s permafrost. "I see a good example of international cooperation here," Putin told a group of scientists.
Today, as Arctic researchers prepare for their summer fieldwork, Samoylov station instead highlights the collapse of international cooperation. German scientists have not been to Samoylov since 2021, and a regular stream of permafrost data has dried up. After Russia invaded Ukraine in 2022, Germany and other European countries joined the United States and Canada in barring their scientists from collaborating on most projects with Russia, which controls half of the Arctic’s coastline. "We are cut off from this part of the Arctic," says Anne Morgenstern, a permafrost scientist at Germany’s Alfred Wegener Institute who coordinated the German presence at Samoylov. "It’s just a tragedy, the whole situation, and everybody hopes that this horrible war ends soon."
The abrupt rupture is jeopardizing data on climate change, oceanography, and ecology that stretch back decades. On Samoylov Island, sensors that measure carbon dioxide and methane emissions from the warming permafrost are likely still operating, Morgenstern says. But none of the data is flowing to German scientists, and she questions how long the observations can be sustained without spare parts or specialized knowledge from Germany. "We suspect it’s going to be very hard for them to maintain the measurements in the long term," she says.
Rebuilding severed ties could be slow. Mike Sfraga, chair of the U.S. Arctic Research Commission, described it as a "tectonic shift" at a February conference in Norway. "If the war stopped tomorrow miraculously, things don’t just turn back on."
Russia continues to pursue Arctic research. It is building a permafrost monitoring network and recently launched the Severny Polyus (North Pole), a research vessel designed for yearslong Arctic deployments, the press office of the St. Petersburg-based Arctic and Antarctic Research Institute said in a statement. Most collaborations with the West "have now been suspended, not on our initiative. Of course, we regret this decision of foreign colleagues, but we continue to work on our own."
Some Western scientists have found workarounds. Jan van Gils, an ecologist at the Royal Netherlands Institute for Sea Research, studies red knots, shorebirds that winter in Africa, then fly 9000 kilometers to Siberia to breed in the summer. He was planning an intensive 4-year field campaign in Russia. Instead, during fieldwork last month in Mauritania, he attached GPS trackers to 80 of the birds in hopes of following them remotely. "Of course the science would even be better if we could study it onsite," he says.
Agencies are also improvising. For years, Russian vessels had serviced a set of Arctic Ocean sensors, funded by the U.S. National Science Foundation, that are moored just outside Russian waters. Instead, the U.S. Coast Guard icebreaker Healy will travel this summer to work on them.
Many scientists are also reorienting their research to more accessible territory in Scandinavia and North America. Morgenstern is working to establish a program on the Mackenzie River in the Canadian Arctic to monitor its water chemistry, including the effects of thawing permafrost. That would take the place of her past work on the Lena River. Bruce Forbes, a geographer at Finland’s University of Lapland, is moving a planned study of the cues that guide reindeer migration across the tundra from Siberia to northern Finland. "I hope I can go back eventually," Forbes says.
As individual scientists and institutions try to move forward, the Arctic Council, an intergovernmental policymaking body, remains in limbo. Composed of officials from the eight Arctic nations, the council doesn’t directly fund research. But it sets research priorities and coordinates scientific activities. After the invasion, most work was frozen when officials from the seven Western countries refused to meet with their Russian counterpart, even though Russia held the council’s chair.
Norway takes over as chair on 11 May. It may try to get all the nations to agree to ground rules that would allow lower level council committees to resume activities that require Russian involvement, says Jennifer Spence, a Harvard University Arctic policy expert who recently served on the council’s Sustainable Development Working Group. That could include publishing scientific reports and supporting researchers monitoring environmental conditions. "Norway is looking for a meaningful way to keep the work of the Arctic Council alive," she says.
In the Barents Sea, Norway and Russia continue to exchange data about fisheries they managed together. But it’s just a sliver of the past cooperation on this shared water body, says Ole Arve Misund, executive director of the Norwegian Polar Institute. "This is the only official contact," he says.
Individual researchers are also struggling to keep lines of communication open. Last year, Norwegian organizers of the largest Arctic science conference, the Arctic Science Summit Week, barred Russians from participating. This year, Austrian organizers of the event allowed Russians to attend as long as they displayed no official affiliation with a Russian institution, such as listing it on a name tag. But only six Russian scientists ended up attending a gathering that drew more than 800 people, and five of those were online.
Vladimir Romanovsky, a Russian-born permafrost expert at the University of Alaska Fairbanks who carries both U.S. and Russian passports, traveled via Turkey to a conference in Siberia’s Yakutsk region this winter, where a good friend leads a permafrost research program. He says he’s glad he went, in part to encourage young researchers he met. "I will continue to support these relations just for those young people to have some hope."
Yet he worries that a program he coordinates tracking permafrost temperatures across the Arctic is imperiled. He has had to abandon his practice of sending money to Russian colleagues to help support their work. He says they are reluctant to accept research money from abroad, fearing they will be labeled a "foreign agent" - which could put them at risk of government scrutiny or arrest. "The coming field season is in big question," he says.

В Институте органической химии им. Н.Д.Зелинского выяснили, что ключевую роль в катализаторах, используемых в тонком органическом синтезе, играют не наночастицы, а отдельные атомы металла, обеспечивающие 99% каталитической активности.

A small team of chemists at the Russian Academy of Sciences, has found that metal atoms, not nanoparticles, play the key role in catalysts used in fine organic synthesis. In the study, reported in the Journal of the American Chemical Society, the group used multiple types of electron microscopy to track a region of a catalyst during a reaction to learn more about how it was proceeding.
Prior research has shown that there are two main methods for studying a reaction. The first is the most basic: As ingredients are added, the reaction is simply observed and/or measured. This can be facilitated through use of high-speed cameras. This approach will not work with nanoscale reactions, of course. In such cases, chemists use a second method: They attempt to capture the state of all the components before and after the reaction and then compare them to learn more about what happened.
This second approach leaves much to be desired, however, as there is no way to prove that the objects under study correspond with one another. In recent years, chemists have been working on a new approach: Following the action of a single particle during the reaction. This new method has proven to have merit but it has limitations as well-it also cannot be used for reactions that occur in the nanoworld. In this new effort, the researchers used multiple types of electron microscopy coupled with machine-learning algorithms.
To test their ideas, the researchers used a carbon substrate with embedded palladium nanoparticles as a catalyst. By studying reactions using such a catalyst with several types of electron microscopes and then training machine learning algorithm with the results, they were able to track a region of the catalyst as it moved through a reaction. They were able to see that there were individual metal atoms as well as clusters in addition to the nanoparticles playing a role in the reaction. Further study showed that approximately 99% of catalytic activity was due to the palladium atoms, rather than the nanoparticles despite them making up just 1% of the palladium mass.

Решение России продлить свое присутствие на Международной космической станции до 2028 года позволит исследователям из разных стран продолжить эксперименты, которые можно проводить только в космосе.

Russia’s decision to extend its support for the International Space Station (ISS) until 2028 is a boon for space science, say researchers who depend on the station to conduct their experiments.
Russia’s invasion of Ukraine last year had thrown into question the future of the space station, and introduced tensions after many Western nations withdrew or ousted Russia from scientific collaborations, including space projects. Russia’s space agency Roscosmos had said in July 2022 that it would leave the ISS after 2024. But, on 27 April, Russia confirmed that it would support operations until 2028.
"It’s very reassuring to see it in black and white, that the extension’s happening," says Adrienne Kish, an astrobiologist at the National Museum of Natural History in Paris. "Some scientists had been biting their fingernails just waiting for the confirmation."
"Right now, the ISS is pretty much the only microgravity spaceflight environment available to scientists," says Anna-Lisa Paul, a plant space biologist at the University of Florida. "The ISS is the only game in town."
The operation of the ISS relies on Russia working with 14 other countries - all of whom have condemned its war in Ukraine. But operation has seemed to continue smoothly since the invasion. The Russian and US orbital segments of the ISS depend on each other, and resupply of the space station relies in part on Russian Soyuz rockets, although resupply missions through commercial companies such as SpaceX are increasingly common. The ISS is expected to finish operating after 2030, according to NASA’s budget estimates.
Experiments continue
The news of Russia’s extended support for the ISS came as a relief to researchers like Kish and Paul, for whom the ability to send experiments to the space station is crucial. Kish studies how radiation exposure in space affects microorganisms and the biological signatures they leave behind. "We need to have access to microgravity and combinations of radiation that are very, very difficult to reproduce on the ground," she says.
Experiments conducted by Kish and her collaborators could help inform the detection of signs of past or current life beyond Earth, including on Mars. "Thankfully, with the extension, we have a better chance of seeing those experiments get to flight," she says. Kish is a collaborator on the Exocube project, which involves the installation of an ‘exposure platform’ on the ISS that allows experiments to be exposed to the vacuum of space. Exocube is expected to launch to the ISS by the European Space Agency (ESA) and industry partners in 2024.
Paul, whose research uses microgravity to study plant behavior and epigenetic adaptation, is in the middle of an experiment comparing samples of plants grown on the space station with plants grown on Earth. The next batch of samples is expected to launch in June, on a SpaceX rocket.
Jean-Pierre de Vera, an astrobiologist at the German Aerospace Center’s Microgravity User Support Center in Cologne, says that although he and his colleagues have been obliged by the German Aerospace Center to suspend scientific collaborations with Russian researchers, they still rely on cosmonauts to conduct their experiments on the space station. The continuation of the ISS until at least 2028 means "there is much more stability" for his research.
De Vera led the Biology and Mars Experiment (BIOMEX) - a joint ESA-Roscosmos space-exposure experiment to investigate the limits of life and potential habitability of Mars, which launched to the ISS in 2014. He is preparing for a follow-up experiment called BIOSIGN, which is expected to launch in 2026.
Commercial launches
Researchers expect that, beyond 2028, there will be more reliance on private companies for research in space. Kish says that the Lunar Gateway - which is expected to be first space station orbiting the Moon and is slated to launch in 2024 - will provide an important platform.
"The extension of the International Space Station enables researchers to continue transformative research that can only be done in space," said Diane Malarik, acting division director of NASA’s Biological and Physical Sciences Division, in a statement to Nature. Being able to continue this research aboard the station, alongside commercial efforts is crucial to maintaining scientific momentum, said Malarik.
ESA’s director of human and robotic exploration David Parker noted that ESA member states decided in 2022 to extend Europe’s participation in the ISS to 2030. In a statement, Parker said that new science facilities on ESA’s Columbus laboratory aboard the station "will include a 3D bio-printer, an external exobiology package and new instrumentation for heat transfer research".

Российские ученые модифицировали табак, добавив ему ген глутатион-S-трансферазы AtGSTF11, играющий важную роль в защите растений от стресса и тем самым повысили устойчивость табака к неблагоприятным условиям - низким температурам, засухе и засоленной почве. Таким же способом можно будет улучшить жизнеспособность и других пасленовых растений, например, картофеля и томатов.

Russian scientists have modified tobacco. They added the AtGSTF11 gene and improved the plant’s resistance to adverse conditions. These adverse conditions include low temperatures, drought and salty soil. Model plants with the new gene used in the experiments showed increased vitality. The scientists have published a description of their experiments in the Russian Journal of Plant Physiology.
Plant stress (caused by a variety of factors - drought, temperature, contaminated soil, etc.) ends at the cellular level with oxidative stress: reactive oxygen species are formed in the cell. They destroy proteins, disrupt the structure of DNA and lead to cell death or interfere with vital functions, the scientists add. There are cellular mechanisms that prevent the development of oxidative stress - low-molecular antioxidant compounds, proteins (antioxidant enzymes), glutathione.
"Glutathione is a short sulfur-containing peptide that plays an important role in protecting plants from stress. It is formed, then cycled into oxidized and reduced forms, and so on. This is the glutathione cycle. In this process, reactive oxygen species are eliminated and plant cells do not die. A number of genes are involved in this cycle. We added another gene, glutathione S-transferase, and got a more viable plant," says Bulat Kuluev, Head of the Plant Genomics Laboratory at the Institute of Biochemistry and Genetics (Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences).
The biologists were able to grow strong plants at a temperature of +15 degrees Celsius (the normal temperature for tobacco growth is +25 … +28 degrees). They were also able to reproduce tobacco plants under sparse watering - up to 50 ml once a week - and in an acidic environment - the soil was watered with a two percent sodium chloride solution.
"Tobacco as an experimental model was not chosen to make life easier for smokers. Tobacco is a very convenient model for research. First of all, tobacco companies used to actively fund research on the plant, and today we know much more about tobacco than about many other plants. A lot of research has been done on its anatomy, physiology, morphology, biochemistry and growth processes. Therefore, any changes we make to the plant are easy to detect. Secondly, tobacco is easy to transform, grows and reproduces well, which also simplifies our task," explains Aleksandr Ermoshin, Associate Professor of the Department of Experimental Biology and Biotechnologies at the UrFU.
The data obtained by the researchers can be applied to crops. For example, the viability of potatoes, tomatoes and other solanaceous plants can be improved. However, scientists have yet to test the resistance of crops with the new gene under extreme conditions.

Исследование ученых Санкт-Петербургского государственного университета, Института геологии и минералогии СО РАН и Алтайского государственного университета показало, что площадь ледников Северо-Чуйского хребта на Алтае с середины XIX века сократилась более чем вдвое и продолжает уменьшаться. Кроме того, в последние годы скорость таяния увеличилась.

La superficie des glaciers du Tchouïa du Nord, un chaînon montagneux faisant partie de l’ensemble montagneux plus vaste de l’Altaï en Sibérie, a diminué de moitié par rapport à ce qu’elle était au 19ème siècle, a annoncé, vendredi, l’Université d’État de Saint-Pétersbourg.
« Nous avons constaté que depuis le milieu du XIXe siècle, les glaciers ont diminué de plus de moitié - et plus que dans d’autres régions de l’Altaï », précise un communiqué de l’université, reprenant les résultats d’une étude menée en partenariat avec l’Institut de géologie et de minéralogie relevant de la Branche sibérienne de l’Académie des sciences de Russie et l’Université d’État de l’Altaï.
Selon Dmitry Ganyushkin, professeur au Département de géographie physique et d’aménagement du paysage à l’Université de Saint-Pétersbourg, la fonte des glaciers s’est accélérée dans la région au cours de la dernière décennie.
« Si jusqu’en 2010, le glacier Maacheï, où nous avons mené des recherches, reculait de 6 à 7 mètres par an, son bord recule désormais en moyenne de 14 mètres par an », a averti le scientifique, cité par le communiqué.
Selon les résultats de l’étude, la fonte des glaciers contribue non seulement à l’expansion de la ceinture forestière, mais elle peut affecter l’activité économique et même menacer les populations. Ce phénomène naturel entraîne une modification de la masse d’eau dans les rivières de montagne au cours de l’année, augmentant les risques d’inondations, d’instabilité gravitaire, d’érosion et de coulées de boue, précise-t-on.
Près de deux cents glaciers se trouvent dans la partie centrale du chaînon de montagne du Tchouïa du Nord pour une superficie totale de glaces de 175 km2. Le glacier Maacheï, qui s’étend sur 19,25 km2, donne naissance à la rivière du même nom.
Le Tchouïa du nord forme avec le Tchouïa du sud les Alpes de la Tchouïa: un système montagneux célèbre pour ses dix grands glaciers prisés des alpinistes.

Одна из задач современной физики - поиск сверхпроводников, способных работать при атмосферном давлении и комнатной температуре. Ученые исследуют различные группы материалов, в частности полигидриды - соединения с высоким содержанием водорода. Группе китайских и российских физиков удалось синтезировать полигидрид лантана-церия, объединив два металла, одному из которых для приобретения сверхпроводящих свойств не требуется низких температур, а другому - высокого давления. Получился компромиссный вариант, устойчивый при давлении 1 млн атмосфер и температуре -97 градусов. Новый материал удобен для экспериментов и будет полезен для дальнейших исследований.

Les supraconducteurs découverts il y a un siècle ne le sont que pas loin de la température du zéro absolu. On en cherche depuis des décennies à températures et pressions ambiantes, ce qui révolutionnerait la technologie. Plusieurs pistes sont explorées avec notamment des hydrures, comme le prouve à nouveau le travail d'une équipe de chercheurs chinois et russes.
Au début du mois de Mars, une petite bombe a explosé dans le monde de la physique de la matière condensée avec l'annonce de l'obtention d'un matériau qui serait supraconducteur à température ambiante et avec des pressions qui bien qu'importantes ne sont pas particulièrement dures à obtenir. Il y a une forte polémique au sujet de la réalité de cette découverte et on le comprend aisément car un composé supraconducteur à température et pression vraiment ambiantes conduirait à une révolution technologique majeure. De tels matériaux, si en plus ils étaient faciles et peu coûteux à synthétiser, feraient faire des bonds de l'imagerie médicale aux transports en commun avec des maglevs, en passant par la fusion contrôlée.
Plusieurs pistes de recherche sont explorées partout dans le monde et tout dernièrement il y a eu une publication dans ce domaine intéressante. Futura y est d'autant plus sensible qu'elle expose une avancée scientifique venant notamment du physicien, chimiste et cristallographe russe Artem Oganov, dont le nom revient assez souvent sur le devant de la scène de la physico-chimie des matériaux à haute pression - Futura suit ses travaux depuis des années. Rappelons que ses recherches l'ont conduit dans plusieurs centres de recherche mondiaux de grande réputation, de l'université d'État de Moscou jusqu'à l'université Stony Brook en passant par l'University College London et l'ETH à Zurich. De retour en Russie et après avoir été membre un temps du mythique Institut de physique et de technologie de Moscou (MIPT pour Moscow Institute of Physics and Technology), il poursuit son exploration de la physique du solide dans le cadre du Skolkovo Institute of Science and Technology (Skoltech) que l'on peut considérer comme l'équivalent russe du MIT aux États-Unis.
Avec des collègues chinois de l'université de Jilin, du Center for High Pressure Science and Technology Advanced Research, Artem Oganov fait donc savoir aujourd'hui que la synthèse d'un polyhydrure de lanthane-cérium prometteur pour faciliter les études de la supraconductivité proche de la température ambiante a été réalisée. Le communiqué du Skoltech qui accompagne la publication dans Nature Communications explique que ce nouveau composé offre un compromis entre les polyhydrures de lanthane et de cérium en matière de refroidissement et de pression requis pour que se manifeste une transition de phase exhibant un état supraconducteur, permettant donc le transport d'un courant électrique avec une résistance nulle en raison d'effets quantiques.
Des polyhydrures comme laboratoire pour la quête des supraconducteurs exotiques
Si l'on fait un rapide état des recherches solidement établies sur les supraconducteurs à température et pression ambiante, on ne peut qu'être d'accord avec le communiqué de Skoltech qui explique que pour le moment on a un spectre de matériaux avec à un extrême un polyhydrure de lanthane de formule LaH₁₀ qui est supraconducteur à -23 °C mais sous une pression de 1,5 million d'atmosphères. C'est typiquement le genre de pression qui nécessite un presse à enclumes de diamants, tout comme dans les expériences sur l'obtention de l’hydrogène métallique il y a quelques années effectuées par une équipe de chercheurs français du CEA et du Synchrotron Soleil qui s'inscrit également dans les recherches sur les hydrures potentiellement supraconducteurs à hautes températures critiques.
À un autre extrême, on a le cas bien connu des cuprates qui sont supraconducteurs sous une pression atmosphérique, mais avec des températures inférieures à -140 °C.
Les chercheurs suspectaient qu'en raison du fait que le lanthane et le cérium sont deux atomes très similaires (ils sont voisins dans le célèbre tableau de Mendeleïev) et qui forment en conséquence des composés analogues et peuvent souvent se substituer l'un à l'autre, on pouvait obtenir un polyhydrures LaH₉ avec du cérium se comportant comme un supraconducteur intéressant (LaH₁₀ et CeH₁₀ ainsi que CeH₉ sont de fait des supraconducteurs) et ils avaient entrepris de tester l'hypothèse.
Le résultat obtenu est commenté par Artem Oganov de la façon suivante :
« La très haute pression force le lanthane pur et l'hydrogène dans la structure LaH₁₀. Mais si vous remplacez environ 1 atome de lanthane sur 4 par du cérium, cela réorganise la structure dans l'arrangement observé dans CeH₉. En ce sens, l'introduction du troisième élément modifie la structure que le matériau pur aurait autrement assumée. Et cet additif contribue à la stabilité : par rapport aux 1,5 million d'atmosphères dont vous avez besoin pour LaH₁₀, notre polyhydrure de lanthane-cérium est stable à seulement 1 million d'atmosphères. C'est à peu près la même pression que les polyhydrures de cérium nécessitent, mais ceux-ci ne présentent une supraconductivité qu'en dessous -158 °C, alors que le nouveau supraconducteur fonctionne à -97 °C. C'est donc un bon compromis, mais plus important encore, c'est une assurance que notre raisonnement est juste.
Les polyhydrures sont un eldorado pour la recherche fondamentale sur les supraconducteurs sous pression. Et en synthétisant notre nouveau composé, nous avons à la fois testé et affiné les outils et astuces utiles dans cette quête et fourni un matériau pratique pour des études ultérieures. »
On ne comprend pas encore très bien ce qui fait qu'un matériau peut devenir supraconducteur à des températures et des pressions moins exotiques que celles des supraconducteurs dits conventionnels, comme le mercure, par exemple. Même si, comme le pense Artem Oganov, les polyhydrures en général ne seront pratiquement jamais rendus supraconducteurs à la pression atmosphérique, on peut penser qu'en servant de laboratoire théorique ils nous livreront des clés pour concevoir des matériaux qui eux le seront et aussi à température ambiante. Peut-être faudra-t-il aller pour cela au-delà de la théorie BCS...

Интервью ведущего научного сотрудника Института востоковедения РАН Баатра Китинова - об истории буддизма в России и его современном статусе.

Dr. Baatr Kitinov is a native Buddhist of the Russian Federation, from the Kalmyk Region, an autonomous region of the Russian Federation. He is currently a Leading Research Fellow of Institute of Oriental Studies, Russian Academy of Sciences, Moscow. Recently in Delhi to attend the Global Buddhist Summit, he spoke to Aditi Bhaduri about the Buddhist community in the Russian Federation; how Buddhism travelled to Russia from India via Mongolia and China; how through the long turbulent centuries of war and imperialism, the Buddhists held on to their faith, and the current status of the Buddhist community in Russia today.
Excerpts from the interview:
IN: When and how did Buddhism first travel to Russia?
BK: Buddhism first appeared in the Russian Far East from China, through Mongolia. It was Chinese Buddhism, and it was in the eighth century AD. Buddhism came to Russia in three waves. The second wave appeared in the beginning of the 15th century. This was also a form of Chinese Buddhism with some Tibetan characteristics. The third and last wave occurred at the end of the 16th century and this was Tibetan Buddhism.
It was the Kalmyks who first moved to the territory of the Russian Federation from South Siberia, to the Caspian Sea (Astrakhan) due to many reasons. In fact, "Kalmak" is a Turkic term. We call ourselves "Oirats". Kalmyks became Buddhists sometime in the middle of the 13th century AD. Till then they were Shamanists and partly Christians. In the middle of the 15th century the Geluk branch of Tibetan Buddhism - the Yellow Hats - arrived in the region and the Kalmyks adopted this branch of Buddhism. In fact, it was the Kalmyks who [helped to] established the power of the Dalai Lama over the Tibetan Buddhists - in 1652 with the fifth Dalai Lama.
In the second half of the 18th century AD the people in the Buryat Region became Buddhists. People in Tuva already had Buddhist temples in the 13th century, perhaps these were Uighur temples. They became followers of the Yellow Hat teaching when they became part of the Jungar Khanate.
IN: How big is the Buddhist community in Russia today?
BK: Russia today is home to approximately one million Buddhists. The Buryat Autonomous Republic has around 400,000 Buddhists, Kalmykia has 135, 000 Buddhists, the Republic of Tuva has 100,000, and the rest are Russian converts mostly.
IN: How was Buddhism preserved over the centuries in this region, so far away from its birthplace?
BK: There is no simple answer. The people of Buryatia and Tuva lived far away from the European part of Russia. The Kalmyks, on the other hand, faced many wars. So it was difficult for them to keep the faith. Yet, they did, in the face of tremendous odds. Their loyalty to the Dalai Lama played a significant role. Their belief in their faith - in karma - played another major role. We believed that everything is karma, and if we were to keep the faith, it would keep our karma clean.
IN: How would you describe the relations between Russia’s Buddhist community and the Russian Orthodox Church?
BK: Relations between the Buddhists and the [Russian Orthodox] Church are currently good. Buddhists are recognised as an official minority. However, under the Russian Tsarist Empire, they tried sometimes to convert "pagans" to Christianity as that was the state policy then. However, towards the end of Tsarist rule, there appeared a wave of Indophiles, especially those interested in Buddhism like Alexander Scherbatsky, and that was helpful for us. During the USSR, all religions were suppressed, not just Buddhists alone.
In the Russian Federation, state and religion are separate. So we do not feel any pressure, there is freedom for us, but we have other issues. We are a weak and economically backward community. So we find it difficult sometimes to preserve our identity. For instance, the state donates land to us for a temple but we are unable to find the resources to build it. We need state patronage.
However, Buddhist teachings are really attractive for many in Russia today. Buddhist studies are developing in Russia today.
IN: Can India do anything for the Buddhist community in Russia?
BK: India can support Buddhists and Buddhism in Russia in various ways. They can send Pali and Sanskrit teachers and train such teachers amongst us. They can promote museum exhibitions, etc.

Коллектив исследователей из 28 стран, в том числе России (Зоологический институт РАН) создал самое большое в мире эволюционное дерево бабочек, состоящее из геномов более 2000 видов. Ученые проследили перемещения и пищевые привычки чешуекрылых во времени и пространстве, что привело их в Северную и Центральную Америку - именно здесь, согласно полученным результатам, 100 миллионов лет назад появились первые бабочки и начали стремительно распространяться по всему миру.

Roughly 100 million years ago, a pioneering group of moths began to venture out during the day instead of night, seizing the opportunity presented by flowers abundant in nectar that had evolved alongside bees. This single event sparked the evolution of the entire butterfly species.
Since 2019, through extensive DNA analysis, scientists have known the precise timing of this evolutionary shift, debunking a previous theory that suggested the rise of butterflies was a result of pressure from bats following the extinction of dinosaurs.
Now, scientists have discovered where the first butterflies originated and which plants they relied on for food.
Before reaching these conclusions, researchers from dozens of countries had to create the world’s largest butterfly tree of life, assembled with DNA from more than 2,000 species representing all butterfly families and 92% of genera. Using this framework as a guide, they traced the movements and feeding habits of butterflies through time in a four-dimensional puzzle that led back to North and Central America. According to their results, recently published in the journal Nature Ecology and Evolution, this is where the first butterflies took flight.
For lead author Akito Kawahara, curator of lepidoptera at the Florida Museum of Natural History, the project was a long time coming.
"This was a childhood dream of mine," he said. "It’s something I’ve wanted to do since visiting the American Museum of Natural History when I was a kid and seeing a picture of a butterfly phylogeny taped to a curator’s door. It’s also the most difficult study I’ve ever been a part of, and it took a massive effort from people all over the world to complete."
There are some 19,000 butterfly species, and piecing together the 100 million-year history of the group required information about their modern distributions and host plants. Prior to this study, there was no single place that researchers could go to access that type of data.
"In many cases, the information we needed existed in field guides that hadn’t been digitized and were written in various languages," Kawahara said.
Undeterred, the authors decided to make their own, publicly available database, painstakingly translating and transferring the contents of books, museum collections and isolated web pages into a single digital repository.
Underlying all these data were 11 rare butterfly fossils, without which the analysis would not have been possible. With paper-thin wings and threadlike, gossamer hairs, butterflies are rarely preserved in the fossil record. The few that are can be used as calibration points on genetic trees, allowing researchers to record the timing of key evolutionary events.
The results tell a dynamic story - one rife with rapid diversifications, faltering advances, and improbable dispersals. Some groups traveled over impossibly vast distances while others seem to have stayed in one place, remaining stationary while continents, mountains, and rivers moved around them.
Butterflies first appeared somewhere in Central and western North America. At the time, North America was bisected by an expansive seaway that split the continent in two, while present-day Mexico was joined in a long arc with the United States, Canada, and Russia. North and South America hadn’t yet joined via the Isthmus of Panama, but butterflies had little difficulty crossing the strait between them.
Despite the relatively close proximity of South America to Africa, butterflies took the long way around, moving into Asia across the Bering Land Bridge. From there, they quickly covered ground, radiating into Southeast Asia, the Middle East, and the Horn of Africa. They even made it to India, which was then an isolated island, separated by miles of open sea on all sides.
Even more astonishing was their arrival in Australia, which remained sutured to Antarctica, the last combined remnant of the supercontinent Pangaea. It’s possible butterflies once lived in Antarctica when global temperatures were warmer, making their way across the continent’s northern edge into Australia before the two landmasses separated.
Farther north, butterflies lingered on the edge of western Asia for potentially up to 45 million years before finally migrating into Europe. The reason for this extended pause is unclear, but its effects are still apparent today, Kawahara explained.
"Europe doesn’t have many butterfly species compared to other parts of the world, and the ones it does have can often be found elsewhere. Many butterflies in Europe are also found in Siberia and Asia, for example."
Once butterflies had become established, they quickly diversified alongside their plant hosts. By the time dinosaurs were snuffed out 66 million years ago, nearly all modern butterfly families had arrived on the scene, and each one seems to have had a special affinity for a specific group of plants.
"We looked at this association over an evolutionary timescale, and in pretty much every family of butterflies, bean plants came out to be the ancestral hosts," Kawahara said. "This was true in the ancestor of all butterflies as well."
Bean plants have since increased their roster of pollinators to include various bees, flies, hummingbirds, and mammals, while butterflies have similarly expanded their palate. According to study co-author Pamela Soltis, a Florida Museum curator and distinguished professor, the botanical partnerships that butterflies forged helped transform them from minor offshoots of moths to what is today one of the world’s largest groups of insects.
"The evolution of butterflies and flowering plants have been inexorably intertwined since the origin of the former, and the close relationship between them has resulted in remarkable diversification events in both lineages," she said.
The study was funded by the National Science Foundation, the National Geographic Society, the Research Council of Norway, The Hintelmann Scientific Award for Zoological Systematics, the European Research Council, the Spanish Ministry of Science and Innovation, the Russian Science Foundation, the Japan Society for the Promotion of Science, the Brazilian National Council for Scientific and Technological Development, and the Museum of Comparative Zoology.

Началась очередная совместная российско-вьетнамская экспедиция на научно-исследовательском судне «Академик Опарин» по изучению биоразнообразия в Южно-Китайском море. Экспедиция проходит в рамках Дорожной карты сотрудничества в области морских исследований на 2018-2025 годы ДВО РАН и Вьетнамской академии наук и технологий.

Research ship Akademik Oparin arrived in Vietnam's central coast on Wednesday for an eighth trip to study marine life in the East Sea.
Departing from Nha Trang, the ship will take 36 scientists and researchers, including 19 Vietnamese, around the East Sea, known internationally as the South China Sea, for a month. This marks the eighth field trip conducted by the Vietnam Academy of Science and Technology (VAST) and Russian Academy of Sciences as part of the "Roadmap for cooperation in marine research for 2018-2025."
At the ceremony to welcome the ship on Wednesday, Chau Van Minh, chairman of VAST, praised scientific results from the previous trips, confirming that many young researchers from VAST had gained experiences from them.
Konstatin Mogilevsky, Russia’s deputy minister of Science and Higher Education, said he appreciated the cooperation between the two academies and cooperation in marine science had been effectively implemented.
Le Huu Hoang, deputy chairman of Khanh Hoa Province, home to Nha Trang, said in previous trips, scientists from the two countries had found "quality bioactive compounds" in Vietnam's marine environment. He said that it was necessary to create conditions for international scientists to participate in research surveys in the East Sea as it would help promote Vietnam's marine science in the international arena.
According to VAST, during a previous trip in 2021, Russian and Vietnamese scientists added hundreds of samples of marine flora and fauna to Vietnam's marine biodiversity data, collected samples for analysis of chemical composition and evaluated potential use in medicine and pharmacy at depths of up to 150m in the East Sea.
The Akademik Oparin stretches 75.5 meters long and has 2,441 tonnage. The ship has five laboratories and is equipped with 30 crew members.

Нейролингвисты Центра языка и мозга Высшей школы экономики выяснили, как шум (обычный и визуальный) влияет на качество чтения - становится ли оно более поверхностным, когда акцентируется значение отдельных слов, а не синтаксические отношения между ними. Оказалось, что аудиальный шум не влияет на понимание прочитанного, но может замедлить чтение. А вот при воздействии визуального шума люди наоборот читают быстрее, возможно, из-за раздражающего эффекта. Качество чтения при этом также не страдает.

Researchers of the HSE Centre for Language and Brain have investigated the impact of both auditory and visual noise on semantic processing during reading to determine if it results in a more superficial reading style that emphasises the meanings of individual words over connections between them in a sentence. It appears that noise does not affect reading comprehension but can cause a decrease in reading speed when even unintelligible conversations are occurring nearby. However, when exposed to visual noise, individuals tend to read slightly faster, possibly due to the irritating nature of the noise. The study findings have been published in PLOS ONE.
In the theory of communication, noise is considered an inevitable aspect of the communication process. Broadly speaking, noise refers to any disturbance in the communication channel or any extraneous signal that interferes with the intended signal. Some examples of noise include advertisements on a website, nearby conversations, music, street performers like jugglers or dancers in a park, and so on.
Noise can be either internal, resulting from conditions such as disease, aging, or brain damage, or external, originating from the environment. External noise can vary in modality, such as auditory or visual, and may or may not match the modality of the target signal. 'Background noise in the street matches the modality of having a conversation but conflicts with the modality of reading a book,' the authors explain.
Previous studies reported negative effects of both auditory and visual noise on reading fluency and comprehension. However, their findings do not present a comprehensive picture. Thus, studies of eye movements found longer fixations, a greater number of regressions and hence longer reading times when subjects were exposed to intelligible or unintelligible background speech. Additionally, older readers took longer when faced with non-linguistic visual noise, such as a certain type of font or blurred script. A negative impact on reading speed due to linguistic visual noise, such as short phrases appearing on the screen alongside target sentences, was also observed.
The impact of noise on reading comprehension can differ based on whether it is visual or auditory. Available evidence suggests that visual noise does not interfere with reading comprehension, while auditory noise may or may not affect comprehension. In particular, comprehension was found to be disrupted by background unintelligible speech, music with lyrics, and non-preferred background music. However, intelligible speech and bar-type noise did not seem to affect comprehension.
According to the authors of the new paper, none of the studies investigating the effect of noise on reading have considered it in the framework of language processing models. Thus, according to a noisy-channel model, when reading under noisy conditions, people tend to process language at a surface level and rely more on the meaning of individual words rather than the way words are arranged in a sentence. This is to say, the authors explain, readers in a noisy environment attempt to infer the relationships between words based on the meanings they convey.
On the other hand, the ‘good-enough’ sentence processing model places a strong emphasis on semantic plausibility, ie on whether the text makes sense, as a key factor in sentence comprehension, regardless of any distracting noise. When a person encounters a sentence, two mechanisms of sentence processing are triggered in their mind simultaneously: a bottom-up, syntactically based algorithmic process and a top-down, semantically based process. 'Semantically based processing can be completed faster if the representation is semantically plausible and aligns with the person's real-world knowledge. By placing less emphasis on syntactic processing, readers may be conserving their cognitive resources,' the authors explain.
This assumption was confirmed in experiments using semantically implausible sentences, eg ‘The dog was bitten by the man’ or ‘The fox that hunted the poacher stalked through the woods.’ Despite grasping the meanings of individual words, the subjects often failed to comprehend the true meaning of the entire phrase and thus missed the absurdity of the sentences and their inconsistency with the real world.
Based on the above theoretical concepts and experimental evidence, good-enough processing prioritising semantic information can be expected in noisy conditions of various types. The objective of the new study was to explore whether auditory and visual noise would result in a greater reliance on semantics during language processing - in other words, whether reading can become more superficial in a noisy environment.
The researchers conducted two experiments. The first experiment involved 38 women and 33 men with a mean age of 22 years, no vision or hearing problems, and no history of neurological or mental disorders.
The subjects were asked to read Russian sentences containing a participial clause. The syntax of the experimental sentences was manipulated to make some of them plausible, eg ‘Dima worked with the president's doctor treating small children’, and others implausible, eg ‘Dima worked with the doctor of the president treating small children’. Each experimental sentence was followed by a comprehension question.
The researchers utilised an eye-tracking device to monitor reading fluency. The background noise used in the experiment consisted of a three-talker babble created by overlapping and merging Russian-language popular science podcasts. All non-speech sounds (such as music, crackling or rustling) were edited out. Each participant read the experimental sentences (which were presented in a randomised order) twice - once with noise and once without noise.
The second experiment involved 30 women and 40 men with a mean age of 23 years. None of them participated in the auditory noise experiment. The equipment and stimuli were identical to those used in the first experiment, but this time, the noise was visual and consisted of short Russian idioms and set phrases, two to five words in length, which appeared next to the target sentence on the screen, eg ‘a carriage and a small trolley’ [‘tons of something’] and ‘making an elephant out of a fly’ [‘exaggerating’].
The results of the first experiment showed that auditory noise affected the overall reading speed. The background babble caused longer fixation on the participial phrase and its preceding word. According to the researchers, longer initial fixations apparently compensated for the noise-induced cognitive load. The equally good comprehension in the presence of auditory noise observed in this study is consistent with the findings of previous studies that used bar-type noise, but contradicts those that used non-preferred music.
In the second experiment, the researchers found a paradoxical increase in the overall reading speed when visual noise was present. 'The increase in reading speed may have been driven by the participants' desire to complete the task quickly, possibly due to the discomfort caused by the visual noise during reading,' say the authors.
At the same time, no significant effect of noise on comprehension accuracy was found. The study participants were able to read sentences even faster while preserving a high comprehension rate in the presence of visual noise.
The findings of this study partially confirm those of earlier studies. Indeed, semantic processing is faster than syntactic processing for sentence comprehension. But neither auditory nor visual noise increased the readers' reliance on semantics, meaning that their reading did not become more superficial. These results, observed for the first time, do not support either the ‘noisy-channel’ or the ‘good-enough’ processing models. According to the authors, this inconsistency does not necessarily indicate that the models in question are incorrect, but rather that further study on this topic is warranted.

В 2029 году Россия планирует отправить к Венере межпланетную станцию. Одна из существенных проблем полета спускаемого аппарата в данном случае - посадка на поверхность планеты. Научный сотрудник Института космических исследований Владислав Зубко предложил траекторию, включающую облет ближайшего к Венере астероида и промежуточную посадку на его поверхность и рассчитал орбиты 117 подходящих астероидов диаметром более 1 км на период с 2029 по 2050 годы, описав 53 возможных сценария.

A recent study submitted to Acta Astronautica examines the prospect of designing a Venus mission flight plan that would involve visiting a nearby asteroid after performing a gravity assist maneuver at Venus but prior to final contact with the planet. The study was conducted by Vladislav Zubko, who is a researcher and PhD Candidate at the Space Research Institute of the Russian Academy of Science (RAS) and has experience studying potential flight plans to various planetary bodies throughout the solar system.
"The motivation behind this study was to enhance the efficiency and success rate of Venus missions by including an asteroid flyby in the flight scheme," Zubko tells Universe Today. "As widely acknowledged, Venus’s particular atmospheric conditions make a mission to the planet a challenging prospect, with designing a spacecraft and achieving a landing being notably difficult tasks. Additionally, Venus’ slow rotation, taking 243 Earth days, restricts potential landing sites on its surface."
For the study, Zubko examined the potential for conducting flybys of 117 asteroid candidates with diameters greater than 1 km (0.62 miles) using the Solar System Dynamics catalog from NASA JPL, referring it his plan as an Earth-Venus-Asteroid-Venus flight plan that could potentially occur using launch dates between 2029 and 2050. Using a variety of calculations, Zubko found 53 mission scenarios with 35 asteroid targets between 2029 and 2050 where a spacecraft could encounter an asteroid while en route to Venus.
Zubko tells Universe Today he believes the "most promising" asteroids for scientific exploration for these mission scenarios are 3554 Amun due to its a M-class (also called M-type) classification, 3753 Cruithne since it exhibits a 1:1 orbital resonance ratio with the Earth, and 5731 Zeus since it’s the largest asteroid examined in the study at 5.23 km (3.25 miles) in diameter. M-class asteroids like 3554 Amun are intriguing targets for scientific exploration - and potential resources for Earth - since they are comprised largely of metal phases (i.e., iron-nickel) and are believed to be the source of iron meteorites that have been found on Earth and Mars. For 3753 Cruithne, a 1:1 orbital resonance with Earth means it completes one orbit around the Sun for every one orbit of Earth. Essentially, their orbital periods are exactly the same, otherwise known as a co-orbital object.
Zubko also mentions asteroids 2002 FB3 and 2002 SY50 as potential targets due to their closest approaches to Earth at less than 0.05 astronomical units (AU), or approximately 7.5 million km (4.6 million miles). Along with identifying asteroid candidates for flybys, Zubko also analyzed a potential flyby of the 2P/Eucke comet and potential landing sites on Venus once the spacecraft finally arrives there.
"We believe that conducting an asteroid flyby while en route to Venus is of great importance as it can significantly enhance the scientific value of a mission to Venus, especially in terms of landing on its surface," Zubko tells Universe Today. "In addition, an impulse-free flyby of an asteroid can help minimize the mission’s costs by combining the exploration of both Venus and the asteroid. The study of asteroids is a high priority for science in general due to their relevance in understanding the history of our Solar System as well as the planetary defense mechanisms (if studying hazardous asteroids)."
Aside from being Earth’s twin in size, Venus boasts one of the harshest environments in the solar system with searing surface temperatures of 475 degrees Celsius (900 degrees Fahrenheit) and surface pressures 90 times that of the Earth. This is a result of its runaway greenhouse effect, which scientists are eager to learn more about and whether Earth could end up like Venus in the distant future.
Will we be able to conduct asteroid flybys en route to Venus, and what new discoveries will scientists make about those same asteroids and Venus in the coming years and decades? Only time will tell, and this is why we science!

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