Октябрь 2022 г.

Российская наука и мир (по материалам зарубежной электронной прессы)

CONTENTS / ОГЛАВЛЕНИЕ


• Latest four-member SpaceX crew, including cosmonaut, welcomed aboard space station
• Structural integrity of New Athos Monastery approved
• Arctic glaciers, a Peruvian volcano, and a Russian famine
• Russia's climate is heating up faster than the rest of the world
• Depths of the ocean told about climate changes during last half a million years
• Excavations uncover the treasures of the ancient inhabitants of the Taman Peninsula
• A new system that could improve robot navigation in uneven terrains
• First known family of Neanderthals found in Russian cave
• Star-shaped nanoparticles may help to fight cancer
• Miniature permanent magnets printed by Russian scientists

На МКС прибыла команда корабля SpaceX Crew Dragon из четырех человек, включая россиянку Анну Кикину. Она стала первым российским космонавтом за 20 лет, отправившимся на станцию на американском космическом корабле. Запуск был осуществлен в рамках соглашения «Роскосмоса» и NASA о перекрестных полетах, подписанного в июле этого года.

A four-member SpaceX Crew Dragon team, including a Russian cosmonaut and the first Native American woman sent to orbit, safely docked with the International Space Station (ISS) on Thursday and moved aboard to begin a five-month science mission.
Rendezvous of the latest NASA expedition to the orbiting laboratory came just after 5 p.m. EDT (2100 GMT) following a 29-hour flight to the ISS as the two vehicles circled the globe some 250 miles (420 km) above Earth off the west coast of Africa, according to a NASA webcast of the docking.
The autonomously flying Crew Dragon capsule, dubbed Endurance, was lofted into orbit on Wednesday atop a SpaceX Falcon 9 rocket launched from NASA's Kennedy Space Center at Cape Canaveral, Florida.
The crew consists of two American NASA astronauts - flight commander Nicole Aunapu Mann, 45, and pilot Josh Cassada, 49 - as well as Japanese astronaut Koichi Wakata, 59, a veteran of four previous spaceflights, and cosmonaut Anna Kikina, 38, the first Russian aboard an American spacecraft in 20 years.
The inclusion of Kikina, the lone female cosmonaut in active service with the Russian space agency Roscosmos, was a sign of continued U.S.-Russian cooperation in space despite escalating tensions between Moscow and Washington.
Kikina joined the SpaceX Crew-5 flight under a new ride-sharing agreement signed in July between NASA and Roscosmos allowing the two countries to keep flying on each other's spacecraft to and from ISS.
The team was led by Mann, the first indigenous woman NASA has sent to space and the first woman to take the commander's seat of a SpaceX Crew Dragon. Mann, a U.S. Marine Corps colonel and combat fighter pilot, is also among the first group of 18 astronauts selected for NASA's upcoming Artemis missions aimed at returning humans to the moon later this decade.
"We look forward to getting to work," Mann radioed moments after the linkup was completed.
On arrival, the Endurance crew spent nearly two hours conducting a series of standard procedures, such as leak checks and pressurizing the chamber between the capsule and ISS, before opening the entry hatches.
A live NASA video feed showed the smiling new arrivals weightlessly floating headfirst through the padded passageway one by one into the station.
They were greeted with hugs and handshakes by the four-member team they are replacing - three Americans and the Italian station commander, Samantha Cristoforetti - as well as by two Russians and a fourth NASA astronaut who shared a Soyuz flight to the ISS last month.
"A lot of people are working hard to make sure our common manned space exploration will continue to exist, to develop further. We are living proof of this," Kikina said in Russian remarks translated to English through a mission-control interpreter during a brief welcoming ceremony.
The Endurance crew marked the fifth full-fledged ISS team NASA has flown aboard a SpaceX capsule since the private rocket venture founded by Tesla (TSLA.O) CEO Elon Musk began sending U.S. astronauts to space in May 2020.
SpaceX has flown eight crewed missions to orbit in all, including non-NASA flights.
The new arrivals are set to conduct more than 200 experiments during their 150-day mission, many focused on medical research ranging from 3-D "bio-printing" of human tissue to a study of bacteria cultured in microgravity.
ISS, spanning the length of a football field, has been continuously occupied since 2000, operated by a U.S.-Russian-led partnership that includes Canada, Japan and 11 European countries.

Сотрудники Научно-исследовательского центра «Экология» СО РАН и Института нефтегазовой геологии и геофизики им. А.А.Трофимука СО РАН обследовали Ново-Афонский монастырь в Абхазии, основанный в 1875 г. Монастырь расположен на склоне горы в геологически активной зоне, соответственно, существует риск повреждения фундамента. Ученые рассчитали остаточный ресурс зданий и сооружений и подтвердили их устойчивость.

Recent scientific investigations have approved the structural integrity of the foundation of the New Athos Monastery in Abhazia.
In 1875, the Orthodox monks of the Mount Athos Panteleimon Monastery received the territory at the future New Mount Athos in Abhazia, then part of the Russian Empire. To prepare the site and begin construction, workers had to level a section of the mountain, resulting in thousands of tons of earth and rock being removed. Since the future monastery was located on a hill and did not have convenient access roads, this caused additional difficulties. During the Russo-Turkish War of 1877-1878, the Turks looted the unfinished monastery, but after the end of hostilities, the construction of the monastery complex buildings continued. By 1900, the monastery was completely ready and consecrated, and Emperor Alexander III brought bells as a gift, which are now located in the highest tower and are still working today.
Employees of the "Ecology" Research Center of the Siberian Branch of the Russian Academy of Sciences, together with colleagues from the Institute of Petroleum Geology and Geophysics (Novosibirsk), examined the structures of the New Athos Monastery.
The monastery is on the slope of a mountain and includes several structures that have had varying amount of maintenance since the nineteenth century. In addition, the monastery complex is located within a geologically active area, and multiple underground springs could potentially damage the foundation.
The academy’s scientists explored the enclosed perimeter around the temple complex, the Cathedral of St. Panteleimon, the bell tower, the residential buildings of the monks, and retaining walls. Scientists used the seismic method and electron tomography to determine the structures’ stability. At the conclusion of the study, it was determined that the foundational stability of the Cathedral of St. Panteleimon was eighty-six percent, and the other structures at seventy-four percent. According to current building codes and regulations, a building is structurally safe if the foundational stability exceeds fifty percent, indicating a bright future for New Athos Monastery.
New Athos Monastery was first inhabited by Russian monks from Mt. Athos, most of whom were exiled from the Holy Mountain by the Greek authorities during the time of the "Name-Worshippers" heresy.

19 февраля 1600 года в Перу началось сильнейшее извержение вулкана в истории Южной Америки - столб пепла поднимался на высоту 32 км. Предполагается, что именно обширный выброс пепла и вулканических газов в атмосферу стал причиной похолодания по всему миру и длительных неурожаев в Северной Европе, ставших, в том числе, причиной Великого голода 1601-1603 гг. в России. Результаты анализа образцов гляцио-морских отложений, собранных на архипелаге Новая Земля экспедицией Института геохимии и аналитической химии им. В.И.Вернадского РАН, подтверждают эту гипотезу, свидетельствуя о резком похолодании в начале XVII века.

On 19 February 1600, the Huaynaputina volcano in southern Peru had the biggest eruption in the recorded history of South America. The eruption column was 32 kilometers tall, and an estimated 13 cubic kilometers of magma were released.
A multidisciplinary team recently published a study in Quaternary Research supporting the idea that a year after the Huaynaputina eruption, its climate effects led to global cooling and catastrophic crop failures in northern Europe. In turn, these food shortages contributed to the Great Famine that killed a third of the Russian population.
Sediment Cores from an Arctic Archipelago
In 2015 and 2017, a group of students, doctoral candidates, and professors from different disciplines participated in an expedition to Russia’s Novaya Zemlya archipelago, one of the least explored regions in the Arctic and one that can be accessed only by ship.
The expedition collected sediment samples from seven fjords in the archipelago. All teams had access to a workstation and laboratory on board the R/V Akademik Mstislav Keldysh, where the samples were cut in half lengthwise. One half was saved for scanning at an onshore laboratory, whereas the other half was analyzed on board the ship for factors such as grain size, mineralogy, chemistry, and biology, explained Valeriy Rusakov, lead author of the study and a geologist at the Vernadsky Institute of Geochemistry and Analytical Chemistry at the Russian Academy of Sciences.
In analyzing core samples dating to the 17th century, the team found a sharp decrease in sedimentation rates, finer grain composition, and smaller biogenic remains of marine organisms. These results suggest a sudden onset of colder weather.
Global Cooling in Historical Records
The team studied historical documents as well as scientific samples. They found that the "drastic decrease in sedimentation in the fjords" in Novaya Zemlya coincided with written records of both the 1600 Huaynaputina eruption and extreme cold weather around the world, from crop failures in northern Europe to a 2-week change in blossoming peach trees in China.
This cooling "led to the Great Famine of 1601-1603, which led to the change of ruling dynasties in Russia," said Rusakov. (The dynasty that emerged, the Romanovs, led Russia until 1917.)
Heli Huhtamaa, an assistant professor at the University of Bern, Switzerland, was not involved with the new research but concurs with its general findings. According to her, the Huaynaputina volcanic eruption is considered to be the most likely culprit of the cold weather experienced in 1601 because the eruption released high quantities of sulfur to the atmosphere. These volcanic gases, which damage foliage and discourage plant growth, took as long as a year to reach northern Europe.
The "coolness of the [1601] summer was a result of these volcanic aerosols high in the stratosphere…and that led to extreme harvest loss," said Huhtamaa. As an example of that loss, she pointed to church records from the municipality of Pöytyö, Finland, which document that of the 142.7 barrels of rye seeds that were sowed in 1601, only 1 barrel was able to be harvested. (A barrel is equivalent to about 146.5 liters.)
"Historical reconstructions of unrecognized climatic processes can be extremely important for understanding the role of the nonhuman world in human affairs," said Andy Bruno, an environmental historian and professor at Northern Illinois University. But he warns that we should be wary of "claims that reduce any complicated historical event to a sole climate trigger."
The eruption of Huaynaputina and shifts in glacial dynamics in the Arctic played a role in the Great Famine in Russia, Bruno said, but were far from the only factor. The extended crop failures exacerbated an ongoing political and social conflict known as the Time of Troubles, which lasted until the establishment of the Romanov dynasty in 1613.
For Jersy Mariño, research that explores the connection between the Huaynaputina eruption and historical events from around the world is essential for recognizing the "cultural and geological value" of this volcano and the importance of studying it. Mariño is a geologist from the Peruvian Geological, Mining, and Metallurgical Institute who has conducted extensive research on the geological history and risk posed by this and other volcanoes in southern Peru.
During a recent expedition to Huaynaputina, Mariño and his team found evidence of six towns and several terraces used for agriculture in the 17th century that were completely buried during the 1600 eruption. (The volcano has not erupted since.)
The scientists recommended that the Peruvian government start archeological expeditions as soon as possible.

По словам российских климатологов, температура в России повышается в 2,5 раза быстрее, чем в остальной части земного шара, а последние семь лет были самыми теплыми за всю историю страны.

Russia is experiencing a rise in temperatures at a faster rate than the world as a whole, Russian climate scientists said.
It is well known that global temperatures are increasing due to climate change, with the rate of warming rising as time goes on. Earth's temperature has risen by 0.14 degrees Fahrenheit per decade since 1880, but since 1981 the rate has been more than twice that.
The nine years from 2013 through 2021 rank among the 10 warmest years on record, according to the U.S. National Oceanic and Atmospheric Administration (NOAA).
Speaking to the Russian daily newspaper Novye Izvestia on Monday, Igor Shumakov, the head of the Russian Federal Service for Hydrometeorology and Environmental Monitoring (ROSHYDROMET), said the past seven years have been Russia's warmest.
"The probability that at least one year in the next five years will be warmer than the warmest year, 2016 exceeds 90 percent," Shumakov said. "The territory of Russia is warming faster than the planet as a whole. Temperatures in the polar region are rising, sea ice is shrinking, permafrost is degrading, and climate change is about to get worse."
Novye Izvestia also cited Vladimir Kattsov, a climate expert at the Voeikov Main Geophysical Observatory Russia, as saying that Russia is warming 2.5 times faster than the rest of the planet.
Kattsov told Newsweek in an email, translated from Russian, that the faster warming in Russia was due to two main factors.
"Land is warming faster than the ocean due to differences in heat capacity," he said.
The Arctic, which contains a significant proportion of Russian territory, is warming especially quickly "due to positive feedbacks operating in the climate system at high latitudes - the so-called 'polar amplification' of global warming," Kattsov added.
Russia stretches over 53 percent of the Arctic Ocean coastline, according to the Arctic Council. This Arctic amplification is a well-documented phenomenon, causing the area to experience much faster warming than the rest of the planet. Loss of sea ice is one of the most cited reasons as to why this occurs because sea ice tends to reflect rather than absorb heat from the sun. When sea ice melts, it leaves behind the ocean surface which is darker and absorbs more heat from the sun - and more heat means more melting sea ice.
Julienne Stroeve, a professor of polar observation and modeling at University College London, told Newsweek she was not sure that the observation that Russia is warming faster than the rest of the planet is correct, but that it "very well could be."
"The amplified warming in the Arctic region is largely a result of the loss of sea ice and also earlier removal of spring snow cover," Stroeve said. "Both of these allow for the ocean and the land to warm up." Stroeve added that Siberia has had record warmth in the past several years, consistent with the aforementioned Arctic amplification.
"I haven't delved specifically into weather patterns for Siberia, but high-pressure ridges are common and if you have a blocking pattern, weather extremes are stuck for longer periods of time," she said.

Российские океанологи совместно с немецкими коллегами описали изменения состава и свойств придонных вод Атлантики за последние 500 тысяч лет. Полученные результаты позволяют понять, как глобальные изменения климата отражаются на локальных процессах в океане и спрогнозировать будущие изменения.

Scientists from the Immanuel Kant Baltic Federal University and Shirshov Institute of Oceanology of Russian Academy of Sciences described changes in conditions of bottom waters of the Atlantic during last 500 thousand years. As oceans plays an important role in formation of global climate, this information can help to understand contemporary changes and predict future variations in temperature and risks connected with them. The results of the research, supported by Russian Scientific Foundation’s grant, are published in the magazine Palaeogeography, Palaeoclimatology, Palaeoecology.
There is a constant interchange of heat and gases, including CO₂, which belongs to greenhouse ones, between oceans and the atmosphere. The circulation of waters - sea currents and mutual drifting of deep and surface layers of different temperatures and salinity - is closely connected with Earth’s global climate. The currents of carbone dioxide on the border "ocean-atmosphere" are controlled by such characteristics as solar energy level, heat exchange, photosynthesis, respiration, formation of carbonate shells and corals and other. That’s why it’s important to understand the mechanisms of change of ocean waters’ condition.
Equatorial Atlantic is one of the most important areas of the ocean, because it participates in redistribution of heat from equatorial to polar latitudes. Nowadays the northern part of equatorial area demonstrates the highest level of temperatures of surface waters in the Atlantic Ocean, that is connected with position of so-called intertropical convergence zone, the area, that influences the heat equation in more polar latitudes of the Nothern Atlantic and climate in general, and also the productivity in the surface layer of the ocean. The productivity of the ocean is a feature, closely connected with the income of organic substance, mineral elements, and also with amount and diversity of its inhabitants. The change in water circulation in equatorial and tropical zones of the Atlantic, that took place at the time of interchange of glacial (cold) and interglacial (warm) epochs, enables to understand the relationship between ocean dynamics and global climate change.
Scientists from the Atlantic Branch of Shirshov Institute of Oceanology of Russian Academy of Sciences (Kaliningrad), the Immanuel Kant Baltic Federal University jointly with colleagues from Keele University (Germany) recorded latitudinal migrations of intertropical convergence zone, and also studied the connection between changes of features of the bottom layer of the ocean with surface productivity and global climate changes.
To achieve this aim the researches studied bottom sea sediments, taken from the depth of about 4000 meters in the southern part of Cape Verde basin. Such sediments, apart from mineral elements, contain shells of foraminifers - sea protista. They form carbonate shells from chemical elements containing in water that surrounds them, in particular from "heavy" and "light" isotopes of carbon and oxygen. These isotopes reflect characteristics accordingly of water masses and global ice. The more "heavy"moleculars the water contained, the larger were the icecaps of the planet and visa versa. Due to this feature it is possible to compare changes in chemical constitution of foraminifers with climatic period in which these shells formed. Moreover, state of shells’ preservation tells about aggressiveness of bottom waters to calcium carbonate. Species richness of foraminifers can tell us about the conditions on the surface and in the depth of the ocean; temperature, water ventilation, existence of biogenic matters.
These researches showed that shift of intertropical convergence zone to the north from the exploration area was followed by warming of surface layer of the ocean and increasing of biological productivity of waters. It is supposed that this shift to the north was preceded by the periods when deep sea layers raise closer to surface. As far as the composition of bottom waters is concerned it emerged that in the exploration area there was an alternative domination of old "ancestor" of cold Antarctic deep water, which was aggressive to calcium carbonate (in the periods of cold climatic intervals) and more "loyal" North-Atlantic deep water (in the periods of warm climatic intervals). Nevertheless, the connection between features of deep waters and climate is nonlinear.
"We singled out three climatic regimes, that existed in exploration area in the period of warm climatic stages: "classic model", "effect of local productivity" and "intense influence of aggressive Antarctic bottom water’. The first two regimes present the intense income of North-Atlantic deep water to the exploration area. The singled out regime "effect of local productivity" corresponds to the intervals of migration of intertropical convergence zone to the north. It is supposed that in the period of the third regime the exploration area was under the influence of waters that were mainly of Antarctic origin", - reports Lyubov Kuleshova, junior research scientist of Atlantic Branch of Shirshov Institute of Oceanology of Russian Academy of Sciences and the author of this article.
"The results we gained enable to understand how global climate changes are reflected in the local processes in the ocean. Reconstructing the changes of chemical constitution of bottom waters and especially their circulation in the past, we can understand the degree of anomality of today’s processes and forecast future climatic changes", - tells Leila Bashirova, candidate of geological and mineralogical sciences, head of the laboratory of Geology of Atlantic of Shirshov Institute of Oceanology of Russian Academy of Sciences, director of Scientific Educational Centre "Geoecology and Sea Nature Management" of the Immanuel Kant Baltic Federal University.

Очередными находками Фанагорийской археологической экспедиции, ведущей раскопки на Таманском полуострове, стали иранский меч IV-VI вв. н.э. и украшения I в. н.э., относящиеся к культу богини Афродиты.

Excavations by the Phanagoria archaeological expedition, supported by the Oleg Deripaska Volnoe Delo Foundation, have uncovered treasures of the ancient inhabitants of the Taman Peninsula, located in the Black Sea Region in the present-day Krasnodar Krai of Russia.
The researchers uncovered a cache of artefacts in a warrior’s burial, containing an ornate Iranian sword from the Migration Period during the 4th to 6th century AD. Also discovered are pieces of a harness, buckles, and belt tips, as well as high status items such as glass jugs, wooden and metal utensils, and wooden boxes with decayed cloths.
The sword suggests a political and cultural connection with the Sassanian or Neo-Persian Empire from modern Iran and Iraq, likely given as a diplomatic gift or taken as a military trophy.
Commenting on the discovery, a member of the project stated: "There is no doubt that this person was a representative of the elite of Phanagoria and was a bearer of the military aristocratic culture of the Bosporan Kingdom in the Migration Period."
The study also excavated a burial site from the 1st century AD within the Phanagorian necropolis, containing the remains of a woman who had a silver medallion placed on the lower part of her chest.
The medallion is decorated with zodiac signs and depicts Aphrodite, the ancient Greek goddess associated with love, lust, beauty, pleasure, passion, and procreation. Such medallions were widespread in the territory of the Bosporan Kingdom as early as 2nd century BC and were used as brooches, accessories that adorned hats and other headgear, or as pendants.
Within the burial are several items of jewellery, including: two rings with images (poorly preserved, probably with images of cornucopia and Eros with wings) and two silver earrings with pendants in the form of doves that relate to the cult of Aphrodite, suggesting that the burial belonged to a cult priestess or worshiper. Also uncovered was a red clay jug with a twisted handle, iron scissors with a bronze handle, a bronze mirror and a bead string containing 157 pieces.
During this period, the ancient city of Phanagoria was a Greek colony, first founded in the Taman peninsula by Teian colonists in the 6th century BC after a conflict with the Persian king Cyrus the Great. The city grew into a major trading centre, that along with the associated necropolis covers an area of 2223.95 acres.
Earlier this year, the project discovered treasure hoards within Phanagoria and other settlements of the Taman Peninsula, indicating that the hoards were deposited by the medieval inhabitants in response to periods of conflict or the threat of invasion. The deposits contained on average, 30-80 Bosporan coins, presumably for everyday purchases, while bigger stashes with 1000 or more coins were presumably the culminated life savings.

Исследователи из ФИЦ «Информатика и управление» РАН и НИУ «Высшая школа экономики» разработали новую систему навигации, которая поможет мобильным роботам передвигаться по пересеченной местности, обходя препятствия. Система основана на адаптированном алгоритме оптимизации и коррекции нелинейных путей (MPPI).

As mobile robots become more advanced, they also become easier to deploy in a wide range of real-world settings. One of the factors that will enable their large-scale implementation is their ability to autonomously move around within different types of environments.
So far, many mobile robots have achieved promising results in navigating simple environments, particularly those with a smooth floor or terrain. In the real-world, however, many environments, including industrial plants, some roads and natural environments, have uneven terrains, with holes or bumps in the ground, clutter and other obstacles.
Researchers at the Russian Academy of Sciences and the National Research University Higher School of Economics in Moscow have recently developed a new navigation system that could improve the ability of mobile robots to move on rough surfaces while also avoiding different types of obstacles. This system, presented in a paper pre-published on arXiv, could help to facilitate the deployment of robots in more complex and cluttered environments with uneven terrains.
"Safe navigation in uneven terrains is an important problem in robotic research," Stepan Dergachev, Kirill Muravyev, and Konstantin Yakovlev wrote in their paper. "We propose a 2.5D navigation system which consists of elevation map building, path planning and local path following with obstacle avoidance. For local path following we use the model predictive path integral (MPPI) control method."
The robot navigation system proposed by Dergachev and his colleagues is based on MPPI, an algorithm to optimize and correct a non-linear paths introduced by researchers at the Georgia Institute of Technology in 2016. For the purpose of their study, the team adapted this algorithm so that it would be suitable for optimizing paths in environments with uneven terrains, using 2.5D elevation maps.
"We use a local elevation map as an input for the MPPI algorithm," Dergachev and his colleagues explained in their paper. "MPPI is guided by terrain traversability values computed by this elevation map. These traversability values are computed from slope steepness, surface roughness and other parameters."
Dergachev and his colleagues evaluated their navigation system in a series of tests on simulated environments, using three different elevation maps. In these tests, the robots had to reach a specific location while overcoming or circumventing three distinct obstacles in its way, namely a truncated cone, a ramp and some pits.
The simulated environments used in these tests were created using the Gazebo simulator and were characterized by different obstacles and types of uneven terrain. The researchers tested their system's effectiveness in these environments using a model of a four-wheeled differential drive robot.
Dergachev and his colleagues found that their system performed remarkably well in their simulations, with the robot successfully circumventing obstacles and navigating uneven terrains almost 100% of the time. To confirm its potential, however, the team will eventually also need to test it in a real-world setting, using a physical robot.
If the system also performs well in a real environment, it could eventually be adapted and used in further research. Ultimately, it could thus promote the development of mobile robots that are better at navigating environments with uneven terrains.
"In the future, we plan to create a more efficient implementation of the MPPI algorithm by parallelizing computations using CUDA/OpenCL toolkits," the researchers concluded in their paper. "Another area of future work will be increasing the robustness of MPPI and adapting it to a larger class of dynamic systems."

Международная команда ученых, в том числе российских (Институт археологии и этнографии СО РАН), опубликовала в журнале Nature результаты исследования первой неандертальской семьи. Анализ останков одиннадцати человек из Чагырской пещеры на Алтае, живших и умерших примерно в одно время, показал наличие родственных связей между ними, в частности, удалось идентифицировать отца и дочь-подростка. Кроме того, у нескольких обитателей Чагырской пещеры обнаружилась генетическая связь с неандертальцами, жившими на несколько тысяч лет позже в пещере Окладникова, расположенной севернее.

Analyzing fossils from a cave in Russia, scientists have found the first known Neanderthal family: a father, his teenage daughter and others who were probably close cousins.
The findings, published on Wednesday in the journal Nature, painted a tragic picture of our extinct relatives, who roamed Eurasia tens of thousands of years ago. The family, part of a band of 11 Neanderthals found together in the cave, most likely died together, scientists said, possibly from starvation.
The study was carried out by a team of researchers that included Svante Pääbo, a Swedish geneticist who for 25 years has been uncovering the secrets of Neanderthals, from extracting their DNA from cave floor dirt to replicating their brain cells. Earlier this month, he won the Nobel Prize for his efforts.
"I would not have thought we would be able to detect a father and daughter from bone fragments, or Neanderthal DNA in cave sediments, or any other of the things that are now becoming almost routine," said Dr. Pääbo, a director at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. "It has been an amazing journey."
For his first study of Neanderthal DNA in 1997, Dr. Pääbo and his colleagues drilled into a skull cap discovered in 1856 in a German quarry. Over the next few years, they gathered more DNA from other museum specimens, collecting hints about the evolution of Neanderthals and their links with living humans. Eventually, Dr. Pääbo and his collaborators dug up enough ancient DNA to reconstruct the entire Neanderthal genome.
The new discovery came from a Siberian cave called Chagyrskaya. Paleoanthropologists with the Russian Academy of Sciences began digging there in 2007, unearthing fragments of Neanderthal bones and teeth. The researchers have also found 90,000 stone tools in the cave, along with butchered bison bones.
The cave may have served as a seasonal home for the Neanderthals. They may have come to Chagyrskaya to hunt bison that migrated each year to graze on the nearby grasslands.
In 2020, Dr. Pääbo and his colleagues published the first DNA findings from Chagyrskaya: a full genome collected from a Neanderthal woman’s finger bone. Her genes showed that she was more closely related to Neanderthals more than 3,000 miles away in Croatia than those just 65 miles away in another cave known as Denisova.
That kinship suggests that the Neanderthals in Siberia did not belong to a single population. They expanded east from Europe at least twice - first to Denisova, then tens of thousands of years later to Chagyrskaya.
Dr. Pääbo’s team continued testing other Neanderthal fossils from the cave. They hit a genetic mother lode, ending up with DNA from 11 individuals: six adults and five children. The fossils - along with the stone tools and bison bones - all rested in the same layer of sediment in the cave.
"Archaeologists call this a ‘short occupation,’" said Laurits Skov, a postdoctoral researcher at the University of California, Berkeley, who was a co-author of the new study. In other words, the bones were all trapped in this layer of dirt within a relatively short span of time, geologically speaking. "But ‘short’ here means a couple thousand years or less."
Still, Dr. Skov thinks that the 11 Neanderthals all lived around the same time. That’s because many of them were close relatives.
To look for kinship among the Neanderthals, Dr. Skov and his colleagues scanned the DNA of the fossils for tiny variations. Two of the fossils shared enough variations that they had to be first-degree relatives. One came from a broken vertebra that appeared to belong to an adult male. The other came from a tooth that seemed to come from a teenage female. If these estimated ages were accurate, then the specimens could have come from siblings, or from a father and his daughter.
The DNA from the fossils allowed the researchers to pin down the relationship more precisely. The scientists took advantage of the fact that mothers pass down an extra set of genes to their children, called mitochondrial DNA. The Chagyrskaya man and the girl had different mitochondrial DNA, ruling out a sibling relationship.
"So that means that we can prove that this was in fact a father and a daughter," Dr. Skov said.
Other fossils offered hints of other familial relationships. The father proved to be a close relative of two other adult males at Chagyrskaya. And an adult woman and a boy also shared enough DNA that they were likely related.
Dr. Skov said that the kinship of the Neanderthals suggested that they all died at once. "It seems to be one event that they all die in," Dr. Skov said. If they had died at different times, that would mean the group would have returned to the same cave over many years to bury each member - a scenario Dr. Skov considers very unlikely.
Researchers have found other evidence of Neanderthals dying in large numbers. In 2010, a team of researchers in Spain reported that a dozen Neanderthals perished around 49,000 years ago when a cave roof collapsed on them.
Dr. Skov said there’s no sign of such a disaster at Chagyrskaya. He speculated that the band’s bison hunts failed one year, leading to starvation.
None of the 11 Neanderthals at Chagyrskaya showed any genetic link to the Neanderthals of the Denisova Cave. But Dr. Skov and his colleagues discovered a connection to a third cave nearby known as Okladnikov. Two Neanderthal fossils found at Okladnikov have genetic links to Chagyrskaya. Dr. Skov and his colleagues combined the 13 Neanderthals from the two caves to create a genetic profile of their entire population.
In one analysis, they compared the genetic diversity of males and females. The researchers found that the Y chromosomes shared by the males were fairly similar. The mitochondrial DNA passed down from mothers to their children, on the other hand, was very diverse.
This pattern emerges in many human societies in which the men tend to stay in the group where they were born and where the women often move to new groups before having children. Dr. Skov and his colleagues concluded that among Neanderthals, it was the women who moved from band to band.
"We estimate that between 60 to 100 percent of women in any community actually come from other communities," Dr. Skov said.
Dr. Skov and his colleagues then added up the genetic diversity in the Neanderthals to get clues about the size of their population. Larger populations tend to have more genetic diversity.
"Given these particular patterns of diversity that we see in the data, we can see that there’s not a lot of it," Dr. Skov said.
That lack of diversity most likely means that Neanderthals in Siberia lived in small bands of 20 people or fewer. It also means that the entire population of Neanderthals in Siberia was very low - perhaps fewer than a thousand. "It’s similar to that of the mountain gorilla, which is an endangered species," Dr. Skov said.
Lara Cassidy, a geneticist at Trinity College Dublin who was not involved in the study, cautioned that the work may only reveal the social structure of Neanderthals who lived on the eastern edge of their range.
The harsh Siberian winters might have kept their numbers lower than elsewhere, she pointed out. Getting DNA from bands of Neanderthal groups in the Middle East or Europe could reveal a clearer picture of how they lived across the entire range.
"There’s going to be more to come, so this is a definite milestone," she said.

Исследователи из Балтийского федерального университета имени И.Канта совместно с итальянскими и испанскими коллегами синтезировали наночастицы уникальной звездообразной формы из золота и оксидов железа, что улучшило их магнитные и оптические свойства. Полученные частицы могут быть использованы в фототермальной и магнитомеханической терапии при онкологии, будучи при этом безопасными для здоровых клеток.

Together with colleagues, a group of scientists from Immanuel Kant Baltic Federal University synthesized nanostructures of gold and iron oxides that have improved magnetic and optical properties because of their unique star shape. The particles obtained are safe for healthy human cells and can be used in tumor therapy. This research was supported by the Russian Science Foundation grant. The results of the study are published in the journal ACS Applied Materials & Interfaces.
Nanoheterostructures are nanoscale objects containing several functional compounds with different physical and chemical properties, for instance, of metal and metal oxide. The mutual location of the components of such a structure determines its magnetic and optical properties. Magnetic properties help to control the nanostructures' activity in the body by using an external magnetic field. Applying a low-frequency magnetic field no this process can induce the destruction of cancerous cells.
The optical properties help to visualize, that is, to track particles in the human body. It can be used for photothermal therapy, during which the cells are heated and destroyed by the light of a certain wavelength. These features can be used together to provide more effective destruction of cancer cells.
Together with international colleagues, scientists from the Scientific and Educational Centre "Smart Materials and Biomedical Applications" (based on Immanuel Kant Baltic Federal University, Kaliningrad), synthesized nanostructures containing gold and iron oxides, which can be used in photothermal and magneto-mechanical cancer therapy. Researchers studied the structure of the resulting particles. The latter were star-shaped and had a core of gold, surrounded by an iron oxide sheath. The scientists proved that the shape and optical response of the particles were excellent for combined cancer therapy.
Moreover, the scientists tested how the particles affect breast cancer cells and cell culture, blood vessel walls are normally formed. The cells were pre-incubated in a culture medium with predetermined concentrations of nanoparticles.
It turned out that the nanoparticles had good biocompatibility - they had low toxicity and did not affect the viability of healthy cells. At the same time, the viability of cancer cells with nanostructures was reduced by 65% after the influence of a variable magnetic field of low frequency. When exposed to light, the viability of cancer cells was reduced by 45% due to the local heating of the nanoparticles. The effectiveness of the approach was also confirmed by morphological changes in cancer cells, including their "shrinkage" after alternating magnetic field or light therapy.
"The purpose of this study was to develop and test multifunctional nanoparticles with special magnetic and optical properties. In biomedicine, such nanoparticles are a promising material for cancer treatment. That’s why in this article we showed not only the detailed characterization of the physicochemical properties of the obtained samples. We also added the results of cytotoxicity upon application of various external stimuli (optical radiation and magnetic field), and showed the effectiveness of both approaches", - says Alexander Omelyanchik, a researcher at the Scientific and Educational Centre "Smart Materials and Biomedical Applications" (based on Immanuel Kant Baltic Federal University, Kaliningrad).
The study was conducted by researchers from the Institute of the chemistry of organometallic compounds (CNR-ICCOM), Italy; the University of Siena (Italy), the University of Florence (Italy), the University of Pisa (Italy), and the University of Zaragoza (Spain).

Уральские ученые определили оптимальные условия для 3D-печати миниатюрных постоянных магнитов с помощью селективного лазерного спекания и порошка на основе редкоземельных металлов. Это позволит запустить мелкосерийное производство магнитов любой формы и с любой комбинацией полюсов, подходящих, например, для миниатюрных электродвигателей и кардиостимуляторов. Сейчас маленькие магниты получают путем разрезания больших, что неэкономично и отрицательно сказывается на свойствах.

Scientists from the Ural Federal University (UrFU) and the Ural Branch of the Russian Academy of Sciences are determining the optimal conditions for 3D printing permanent magnets from hard magnetic compounds based on rare-earth metals. This will make it possible to start small-scale production of magnets, in any shape, and create complex magnet configurations. Such magnets are suitable for miniature electric motors and electric generators, on which pacemakers work. In addition to this, as is typical of AM, the technology minimizes production waste and has a shorter production cycle. A description of the method and experimental results are presented in the Journal of Magnetism and Magnetic Materials.
Permanent magnets remain magnetic field sources for a long period. This property is used in a wide variety of industries and devices, such as the manufacture of modern electric motors, household and computer equipment, and other appliances. Traditional methods of manufacturing permanent magnets only allow for the creation of large products, and usually have two poles - one north and one south.
Creating complex and small magnets is not an easy task, scientifically and technically, however, as it turns out, one of the most promising ways to create complex-shaped parts from magnetically hard materials is with 3D printing. Ural scientists have managed to determine the optimal parameters for the 3D printing of permanent magnets using selective laser sintering - and magnetic powder.
3D printing makes it possible to change the internal properties of the magnet at almost all stages of production. For example, to change the chemical composition of the compound, the degree of spatial orientation of crystallites and crystallographic texture, and to influence the coercivity (resistance to demagnetization).
"Making small magnets is a difficult task. Now they are created only by cutting a large magnet into pieces, because of the mechanical processing about half of the used material turns into garbage. Also, cutting introduces a lot of defects in the near-surface layer, which causes the properties of the magnet to deteriorate enormously. Additive technologies allow to avoid this and make complex magnets, for example, with one north pole and two spatially separated south poles, or a magnet with five south poles and five north poles at once. Such configurations are necessary for pacemakers, where it is only possible to assemble the rotor for an electric motor from separate magnets under a microscope," explained Dmitry Neznakhin, Associate Professor at the Department of Magnetism and Magnetic Nanomaterials and Researcher at the Section of Solid State Magnetism at UrFU.
The Russian scientists have already succeeded in producing thin (about one millimeter), permanent magnets whose properties are similar to those of industrially-produced magnets. The base that was used was a powder containing samarium, zirconium, iron, and titanium. The compound has suitable characteristics for permanent magnets, but traditional manufacturing methods deprive the compound of most of its properties. Therefore, the scientists decided to see if the properties could be preserved through 3D printing technology.
"When creating permanent magnets based on these compounds using traditional methods, the properties of the finished products are far from the theoretically predicted ones. We found that when sintering a sample, adding a fusible powder from an alloy of samarium, copper, and cobalt allows the magnetic characteristics of the main magnetic powder to be retained. This alloy melts at temperatures lower than the properties of the main alloy change, which is why the final material retains its coercive force and density," added Dmitry Neznakhin.
At the moment, the scientists are establishing the basic laws of formation of the microstructure and magnetic properties of hard magnetic materials, and are determining which magnetic materials can be used to manufacture permanent magnets using the SLS. This includes testing how the sintering method affects the properties of another known base for magnets - an alloy of neodymium, iron, and boron. The next stage of the work will be the production of bulk permanent magnets suitable for practical applications. The research was supported by the Russian Science Foundation (grant no. 21-72-10104).

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