Российская наука и мир (дайджест) - Август 2018 г.
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Российская наука и мир
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    National Geographic / August 6, 2018
    What DNA From Pet Foxes Teaches Us About Dogs - And Humans
    A Soviet-era experiment to breed tame and aggressive foxes has produced surprising revelations about social behavior and domestication.
    • By Jason G. Goldman
    Расшифровав геном одомашненных лис, выведенных в Институте цитологии и генетики СО РАН, международная группа ученых (Россия, США, Китай, Дания) обнаружила гены, которые отвечают за «ручное» и агрессивное поведение. Открытие может пролить свет и на поведенческие особенности у людей.

For nearly 60 years, Russian scientists have bred foxes to be tame - or aggressive. A new study looking at the genomes of the two groups shows that the experiment has changed the animals' DNA in surprising ways. The research has relevance for understanding social behavior across animals and even humans.
It took a while to get to here. In 1959, a man named Dmitri Belyaev began an experiment designed to understand how dogs became domesticated. Belyaev and other biologists believed that domestic dogs were descended from wolves, but did not yet know how all the anatomical, physiological, and behavioral differences between the two animals could arise.
But Belyaev had a hunch. He suspected that the key component was the dog's tameness. Perhaps, he hypothesized, the biological changes in domesticated animals - white spots, curled tails, floppy ears, shortened skulls - were the result of an evolutionary selection process over behavioral traits rather than anatomical ones.
Fearful and Friendly
Belyaev believed that by breeding the friendliest foxes with each other, perhaps he could domesticate them, artificially mimicking the millennia-long process through which wolves became dogs. He bought up a group of silver foxes from a Canadian fur farm and got to work at his lab in the Soviet Union.
Belyaev would eventually prove himself right. Breeding the least fearful foxes with each other resulted not only in animals that were eager to seek out a social connection with humans, but also in animals that displayed the suite of anatomical features associated with domestication: those characteristic white spots, curly tails, floppy ears, and so on.
The entire collection of modifications associated with domestication could be brought about simply by breeding foxes according to their response when approached by a human. Would they approach the experimenter with curiosity and permit physical contact? Or would they back away, hissing and yelping out of fear?
Belyaev died in 1985, but the experiment continues today. Researchers have bred more than 40 generations of friendly and aggressive foxes. And now, for the first time, they have a fully sequenced fox genome to help understand the genetics that underlie the transition from wild to tame, as described in a study published today in the journal Nature Ecology and Evolution.
The researchers sequenced the genes of 10 foxes from the aggressive and tame populations, and assembled a complete genome of the silver fox (Vulpes vulpes). This has and will continue to allow them to find genetic differences that could underlie different aspects of domestication, says University of Illinois biologist Anna Kukekova, who led the study.
Until now, researchers have had to rely on the domestic dog genome as a reference. But while wolves and foxes diverged only 10 million years ago, dogs and foxes have dramatically different lifestyles.
Genetic Secrets
Kukekova and her colleagues zeroed in on one of the 103 genomic regions that differed between the tame and aggressive foxes. This analysis found that the tamest foxes had a version of a gene called SorCS1 that did not appear in either the aggressive or conventionally-bred foxes. Meanwhile, a different version of SorCS1 most common in aggressive foxes was incredibly uncommon in the other groups.
There was no prior reason to suspect that SorCS1 was associated with social behavior. "It was known to be associated with autism and Alzheimer's disease [in humans]," says Kukekova. And a mouse study recently found that SorCS1 is involved in synapse formation and neuronal signaling. This paves the way for understanding how the gene might affect social behavior, she says.
Domesticated animals experience less stress than wild creatures when confronted with unfamiliar people or objects, and the paper turned up genes that may be involved in this behavioral difference, which is tied to a blunted response in the hypothalamic-pituitary-adrenal, or HPA, axis. This series of biological structures form a connection between the brain and endocrine systems in the body that activates in response to stress.
The study also turned up one genomic region of interest that has been associated with domestication in dogs and with Williams-Beuren syndrome in humans, a genetic condition associated with exceptionally friendly behavior. Surprisingly, though, the "Williams-Beuren region" shows up in the aggressive foxes, rather than the tame ones.
Kukekova points out that Williams-Beuren syndrome is also characterized by extreme anxiety, however, and that is indeed consistent with the foxes' more fearful response to humans. And Princeton University evolutionary biologist Bridgett von Holdt, who was not associated with the study, points out that some dogs can be incredibly aggressive, even if they develop strong, friendly bonds with their owners. To really sort out the subtleties, she adds, will require a lot more research.

Copyright © 2015-2018 National Geographic Partners, LLC. All rights reserved.
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    EurekAlert / 6-Aug-2018
    Scientists develop unique materials to repair damaged organs and tissue
    Scientists created unique polymeric materials for medical purposes that repair traumatized human organs.
    В рамках Проекта 5-100 в Санкт-Петербургском политехническом университете Петра Великого ведется разработка полимерных аналогов живых тканей. Пористый материал из биосовместимых хитозана и коллагена внедряется в поврежденный орган, не вызывая отторжения. По мере восстановления естественные ткани замещают искусственные, которые постепенно распадаются.

Tissue engineering is the future of medicine. Under Project 5-100, the Polymer Materials for Tissue Engineering and Transplantology Laboratory of Peter the Great St. Petersburg Polytechnic University (SPbPU) created unique polymeric materials for medical purposes that repair traumatized human organs.
The laboratory specialists developed a three-dimensional porous material made of collagen and chitosan, an analog of bone tissue. Using this material, the researchers can restore parts of bone lost as a result of trauma or illness.
According to the scientists, this is a completely new medical area not only in Russia but in the whole world. The terminology has not yet been defined. They are currently called "mimicking" materials, as they trick the body. The polymer matrix is implanted into damaged liver tissue, bones or vessels, saturated with the cells of these organs. Since the materials are made from biocompatible components (chitosan and collagen), the body is tricked and does not reject the foreign object. Over time, the matrix decomposes and the artificial tissue is replaced by natural tissue.
"We are not deceiving nature, we are just helping it to cope with a medical problem. Experts are currently debating whether it is better to use an implant or restore an organ. A person with an artificial organ must take medication for the rest of their lifetime to prevent the body from rejecting it. This is not the case for tissue grown from human cells," explains Vladimir Yudin, Head of the Laboratory.
The development of artificial organs for transplantology is an urgent priority of modern medicine. The successful development of this area largely depends on the creation of biocompatible and bioresorbable polymer materials. The scientists of St. Petersburg Polytechnic University have not only developed the technology to create biocompatible materials that stimulate the restoration of natural tissues, but also managed to regulate the resorption time of the materials. It is very important for the implanted materials not to disintegrate before the new fabric is formed.
The results of preclinical studies showed that after a certain period of time, a three-dimensional sponge embedded in a bone starts to become covered with natural bone tissue, while the material itself decomposes. In addition, the developed collagen sponge was studied both in liver tissues and in muscle tissue - the material also stimulated the restoration of the natural tissue of the organs. The latest research results are described in the article "Bioresorption of Porous 3D Matrices Based on Collagen in Liver and Muscular Tissue" published in the journal Cell and Tissue Biology.
The researchers also developed wound covers, prostheses of blood vessels, and suture threads. In vivo preclinical trials were conducted with these materials, and the results proved that they are effective. The materials are recommended for use in tissue engineering and cellular transplantation.

Copyright © 2018 by the American Association for the Advancement of Science (AAAS).

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    EurekAlert / 6-Aug-2018
    Could climate change affect the development of Turkic Khaganate?
    Scientists of Ural Federal University defined the causes of growth and decline of the nomadic empire of the ancient Turks.
    Историки из Уральского федерального университета пришли к выводу, что одной из причин упадка Тюркского каганата, кочевой империи древних тюрков, стали природные аномалии, в том числе периодические длительные засухи, а также сильное и продолжительное похолодание в VI-VII веках.

"According to paleoclimatologists, the main cause of the majority of climatic extremes of that period was volcanic activity. Often these changes occurred on a global scale," explains Rustam Ganiev. "The main consequences of natural disasters - in our case in the territory of the Türkic Kaganate - were the cooling and prolonged droughts of 536, 581 and 679, as well as an early and protracted winter with heavy snowfalls. The most critical situation was noted among the Turks in 627-630, when the Khaganate practically ceased to exist because of the mass death of livestock and hunger."
The authors of the article singled out several periods during which the most important events that changed the course of Turkic history took place:
534-550 - The first mention of the Türkic Khaganate and its "Golden Age";
581-583 - Separation of Khaganate into the Western and Eastern Khaganates;
627-630 - The conquest of the eastern Turks by China;
679-687 - The Second "Golden Age" of the Eastern Turks.
In the first period 536, 537, 541, 543 and 545 years were anomalously cold. The consequences were severe for many people of Middle Ages: one of the most serious epidemics occurred - the Justinian Plague - the first historically known pandemic, with millions of victims.
"It was believed that the plague started in Egypt in 540-541, reached Constantinople through the Mediterranean channels and spread through Byzantium, North Africa, Europe, Central Asia, and Arabia," explains Rustam Ganiev. "However, according to recent studies, the causative agent of plague appeared in Central Asia, where the Turks lived. As the Silk Road ran through this territory, traders could spread the pandemic: Byzantium was the main trading partner of the Khaganate and China; about 80% of the population in the northern part of which died at that time. It was at the end of this period that the Turks began to strengthen their position: they subjugated their neighbors, concluded trade and military-political agreements with China, and by 551 became independent, and their ruler receive the title "khagan".
During the study, the authors of the article used data from tree-ring chronologies (show climatic differences), samples of ice cores of Greenland and Antarctica (volcanic eruptions). The third set of data formed the Chinese dynastic chronicles, which reflect the main historical information about the ancient Turks.
"The Ural Division of the Russian Academy of Science has the largest in Europe, and perhaps in the world, amount of fossil wood. For nearly 40 years, the Institute's employees have been collecting semi-fossil wood on the Yamal Peninsula. To build the "Yamal chronology," they have studied more than 3,500 samples," explains Vladimir Kukarsky. "In the study, we rely on ice core data, the Yamal, Altai, Mongolian tree-ring chronologies, which can be found in the public domain. There was a large number of materials, and we had to choose the ones suitable for our research: to select chronologies that react to changes in temperature, humidity of the territory, extreme events. For example, a volcanic eruption in the tropics can be traced in tree rings in both Altai and Yamal: a huge amount of ash creates the effect of a "volcanic winter," and thin rings form in the trees, and sometimes the cellular structure is broken."
According to the researchers, dendrochronology is one of the most accurate ways to date extreme events in nature. "We plan to apply for a grant to extend the chronology of research to the millennium. A more global goal is to create a historical and climatic chronology for the nomadic societies of Central Asia in the first millennium of our era. This is a very complex, large, labor-intensive and expensive project," says Rustam Ganiev.
The results of the study are published in the journal Climatic Change.

Copyright © 2018 by the American Association for the Advancement of Science (AAAS).

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    Fox News / August 13th
    Frozen woolly mammoth found in Siberia could be new species, researchers say
    • By Chris Ciaccia
    На острове Котельный в Якутии найдены отлично сохранившиеся останки карликового мамонта возрастом около 50 тыс. лет. Мелких мамонтов находили в этой местности и раньше, но впервые - в таком хорошем состоянии. Это поможет прояснить вопрос, являются ли карликовые мамонты самостоятельным видом или генетической аномалией.

Fossils found in Siberia of a tiny woolly mammoth could be an entirely new species, researchers say, with some dubbing it a "Golden mammoth."
The woolly mammoth is tiny and has been described as a "pygmy," at just seven-feet tall. Woolly mammoths averaged between 9 and 11 feet tall, with some approaching 15 feet in height, according to TED.
This mammoth was found in Siberia on Kotelny island and could be 50,000 years old, according to experts. Like rings in a tree, scientists are able to discern a mammoth's age by looking at the rings of its tusks, going so far to tell when what season the animal died. Darker rings indicate the creature died during warmer months.
According to the Daily Mail, the recently discovered mammoth has been given the nickname of a "golden mammoth," due to the color of its fur. It is now embedded in undersea permafrost and is only visible during low tide on the island, located between the Laptev and East Siberian seas.
According to Dr. Albert Protopopov, who is the Chief of the Mammoth Fauna Research Department at Yakutian Academy of Sciences, said that it's still a question of whether this mammoth was an anomaly or not, but coming across its carcass will allow them to answer questions.
"We are yet to discover whether this is an anomaly, or something quite typical for this area - when a grown up mammoth looks like a pygmy," he told the Siberian Times. "We have had reports about small mammoths found in that particular area, both grown ups and babies. But we had never come across a carcass. This is our first chance to study it." Discoveries of smaller or pygmy mammoth remains are not uncommon. Remains have been found off the coast of California and in the Arctic, but Dr. Protopopov believes the new findings are a new species, unrelated to the so-called island effect, which has been bandied about by researchers as causing a decline in the population of mammoths, which eventually died out about 4,000 years ago.
"It is a different thing," Dr. Protopopov said, when asked about whether the new find was related to the mammoth remains found on Wrangel Island. "I think that our new mammoth is not related to the Wrangel mammoth population. This was a different era and different case."
While it's not yet known what researchers will learn from the aforementioned woolly mammoth, some scientists have pondered that reintroducing some of the mammoth's permafrost-preserved DNA could help with climate change.
Speaking with Live Science in May, George Church, a Harvard and MIT geneticist who is the co-founder of gene-editing tool CRISPR and is heading up the Harvard Woolly Mammoth Revival team, said it may not be desirable to bring back the creature in its entirety. However, introducing a few of its genes to Asian elephants could help increase their tolerance to the cold.
"The elephants that lived in the past - and elephants possibly in the future - knocked down trees and allowed the cold air to hit the ground and keep the cold in the winter, and they helped the grass grow and reflect the sunlight in the summer," Church told Live Science. "Those two [factors] combined could result in a huge cooling of the soil and a rich ecosystem."
The Siberian mammoth remains are set to be excavated from their grave next summer.

© 2018 FOX News Network, LLC. All rights reserved.

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    UrduPoint News / Mon 13th August 2018
    Findings In Chagyrskaya Cave In Russia's Altay Suggest Neanderthals Had Sense Of Beautyy
    • Mohammad Ali
    Ученые Института археологии и этнографии СО РАН обнаружили на стоянке неандертальцев в Чагырской пещере на Алтае кристалл горного хрусталя. Кристалл был намеренно отломлен от друзы, не имел следов использования и, вполне вероятно, принесен на стоянку из эстетических соображений. Это говорит о том, что неандертальцам, по крайней мере, не было чуждо чувство прекрасного, как считалось ранее.

Scholars from the Archaeology and Ethnography Institute of the Siberian Branch of the Russian Academy of Sciences have found at Chagyrskaya Cave in the Russian Altay Mountains, which used to be inhabited by Neanderthals, a piece of quartz crystal believed to have been brought to the cave for aesthetic purposes, which could indicate that these early humans had sense of beauty, Ksenia Kolobova, the institute's researcher, told reporters on Monday.
"We have found in the occupation layers of Chagyrskaya Cave a small quartz crystal, which, according to our geologist, had been brought [to the cave] from the outside. A trace evidence expert examined this crystal and did not find traces of it ever having been used, but he did find that [the piece] was broken off a [larger] crystal on purpose. Thus, we can assume that the Neanderthals deliberately brought this piece of beautiful rock crystal to the cave and but did not utilize it in any way," Kolobova said.
Kolobova explained that it was thought that the Neanderthals did not have sense of beauty or produce artifacts, a theory that was now being challenged by the recent finding.
"Here we can conclude that [the Neanderthals'] cognitive abilities were developing, which was previously thought to be impossible. Now we can state that [the Neanderthals] liked something beautiful and they brought it on purpose. We can speak about the sense of beauty, [the need for which they addressed] by carrying out a specific sequence of actions," Kolobova indicated.
The archaeologists now intend to search for nearby quartz deposits, as well as chalcedony and jasper deposits that were used by the Neanderthals to make stone tools in the surrounding areas. "We will find out from where, how and why they were bringing [these rocks]. It used to be thought before that the Neanderthals just picked up a pebble from the ground and used it somehow. But this is not like that," Kolobova revealed.
Chagyrskaya Cave is situated in the southern part of the Altay Territory. The archaeological research of the past decade has proved that the Neanderthals came to the area about 60,000 years ago from the territory of Eastern Europe. According to scholars, the Neanderthals might have reached the Altay territories by following the bison they were feeding on.

© 1997-2018, UrduPoint Network.

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    Bellona / August 21, 2018
    Russian scientists cataloguing radioactive waste dumped in the Arctic
    • By Charles Digges
    Экспедиция Института океанологии РАН, которая продлится до 20 сентября, исследует места возможного затопления радиоактивных отходов в Карском море.

Russian scientists have taken to the seas in a research vessel as part of an effort to locate and map radioactive radioactive waste, nuclear reactors and other castoffs the Soviet Navy scuttled in the Arctic's Kara Sea.
Mikhail Flint, head of the Russian Academy of Sciences institute of Oceanology, told the official Tass newswire the Akademik Mstislav Keldish research ship left Arkhangelsk Friday for the waters near the Novaya Zemlya Archipelago, a former Soviet nuclear bomb testing range around which Russia's nuclear Navy routinely shed its radioactive waste.
Flint, who is heading the expedition, said the crew would scour inlets along Novaya Zemlya's craggy coast to measure possible radioactive leakage from what he said were thousand of containers of nuclear waste, as well as entire reactors that were sunk while still loaded with spent nuclear fuel.
"There is a huge number of dumping sites in the bays of Novaya Zemlya," Flint told Tass. "The sea is a mobile environment, and any leakage could lead to an uncontrollable transfer of radiation."
Such expeditions, Flint said, are undertaken on a yearly basis. As yet, he said, no major leakage has been detected.
The expedition will continue for the next month and a half and encompass not only the waters surrounding Novaya Zemlya. The vessel will conducted additional research mapping radioactive hazards in the White Sea, and then progress to the Laptev Sea some 2000 nautical miles to the east.
Beginning in 1955 and continuing until the early 1990s, the Russian Navy dumped enormous amounts of irradiated debris - and it one case an entire nuclear submarine - into the waters of the Arctic. It was not, however, until 2011 that the Russian government admitted this on an international level.
That year, Moscow shared with Norwegian nuclear officials the full scope of the problem. The list of sunken objects was far more than had initially been thought, and included 17,000 containers of radioactive waste; 19 ships containing radioactive waste; 14 nuclear reactors, including five that still contain spent nuclear fuel; the K-27 nuclear submarine with its two reactors loaded with nuclear fuel, and 735 other pieces of radioactively contaminated heavy machinery.
Moscow routinely promises to lift the submarine, but actual plans to do have yet to materialize.

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    UrduPoint News / Wed 22nd August 2018
    Two Russian Physicists Win William Begell Medal At International Heat Transfer Conference
    • Umer Jamshaid
    Российские физики Александр Федорец и Леонид Домбровский награждены медалью имени Уильяма Бегеля за достижения в области теплоэнергетики.

Two Russian physicists, Alexander Fedorets and Leonid Dombrovsky, have been awarded the William Begell Medal for a profound contribution to the thermal science at the 16th International Heat Transfer Conference (IHTC), Tyumen State University said on Wednesday.
The IHTC conference, held every four years, took place in Beijing on August 10-15.
"The international committee of world renowned scientists took a vote by secret ballot. Following the scoring, one of the 28 lectures was recognized as the best, and both authors [Fedorets and Dombrovsky] were awarded the William Begell Medal and relevant certificates," the university announced.
The lecture of the Russian physicists summed up the milestones of the year-long laboratory study.
The study looks into the phenomenon of self-assembled stable clusters of droplets levitating over the locally heated water surface, which was discovered by Fedorets back in 2004, the university specified.
Dombrovsky works as a chief researcher at the Joint Institute for High Temperatures of the Russian Academy of Science, while Fedorets is the head of a lab at Tyumen State University.
The William Begell Medal for Excellence in Thermal Science and Engineering was established in 2010. The medal is awarded to an individual from among those selected to deliver keynote lectures at the IHTC conference.

© 1997-2018, UrduPoint Network.
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    Scientific American / August 22, 2018
    When a Neandertal Met a Denisovan, What Happened Was Only Human
    Scientists describe the hybrid child of two starkly different human groups.
    • By Richard Conniff

    Генетический анализ фрагмента кости девочки-подростка, жившей 50 тыс. лет назад в Денисовой пещере на Алтае, показал, что ее родители принадлежали к разным видам людей: денисовцам и неандертальцам, разделившимся примерно 400 тыс. лет назад. Это говорит о том, что две ветви не просто существовали какое-то время параллельно, но и контактировали между собой.
    Исследование было проведено международной группой ученых под руководством известного палеогенетика Сванте Паабо из Института эволюционной антропологии Макса Планка. В работе принимали участие ученые из Германии, Канады, Великобритании и России (НГУ и ИАиЭ СО РАН).

In a remarkable twist in the story line of early human evolution, scientists have announced the discovery of "Denisova 11" - a female who was at least 13 years old, lived more than 50,000 years ago and was a child of mixed parentage. Her parents were not just of different races, but two different and now-extinct early human types. Their exact taxonomic designations - whether they were separate species or subspecies - is still a matter of scientific debate. But the bottom line for Denisova 11 is that mom was a Neandertal and dad a Denisovan.
The research, published Wednesday in Nature, is the work of a team led by pioneering paleogeneticist Svante Pääbo at Max Planck Institute for Evolutionary Anthropology in Germany. He and his co-authors published the first description of the Denisovans in 2010, based on genetic evidence from one of the 2,000 or so bone fragments found in Denisova Cave in the Altai Mountains, where Siberia borders Mongolia and China. The new discovery is based on another bone fragment from that lot, a 2.5-centimeter-long fragment of what was a femur or humerus, from which the researchers extracted six DNA samples and then cloned them for detailed analysis.
Molecular dating indicates that Denisovans, who are so far known only from Denisova Cave, and Neandertals, known mainly from sites in Europe, diverged from each other almost 400,000 years ago. They coexisted, probably in relatively small populations scattered across the vast Eurasian landmass, until both became extinct some 30,000 to 40,000 years ago.
But the genetic evidence from Denisova 11 and other recent studies suggests that, on the occasions when they met, Denisovans and Neandertals commonly mated with each other - and with modern humans. Denisova 11's father carried a small amount of Neandertal ancestry, the study notes, from "possibly as far back as 300 to 600 generations before his lifetime."
Sharon Browning, a statistical geneticist at the University of Washington who was not involved in the research, praises the new study. "I'm really kind of blown away by it," she says. "Just to catch the offspring of these two different groups is really remarkable."
"It looks absolutely solid," adds University of Utah population geneticist Alan Rogers, who also was not part of the work. "I think these guys, as usual, have done a great job." Asked if Denisova 11 might have simply been the offspring of a mixed Neandertal-Denisovan population - rather than of a mother and father of two such starkly separate backgrounds - Rogers says, "I felt that their analysis made sense. I was convinced by that. It's not surprising that the two species would mate, if they were together at the same place and time," he adds. "But I don't think we knew before now that they were together at the same place and time - and if they were, it raises the question of why they were so different." That is, why didn't they evolve into a single species?
"It's a really interesting question," says Harvard University geneticist David Reich, who did not take part in Pääbo's study. "At Denisova Cave we are clearly looking at an area where these two groups washed across one another, within walking distance of the cave. But there must have been a lot of isolation, as well as mixture." The hybrid offspring from such divergent populations, Reich says, may have experienced biological problems. Or they may have faced cultural bias, Pääbo notes, if people of mixed backgrounds were "not very well accepted in the cultures of that time."
Even so, both Neandertals and Denisovans have persisted in the modern human genome. A small percentage of Neandertal ancestry is common in all modern human populations outside Africa; some Denisovan lineage is also common among people from east Asia and Oceania. Earlier this year a study led by Browning indicated the modern Denisovan inheritance derives from at least two separate populations, suggesting they were once dispersed far beyond the Denisova Cave. Pääbo says the next step for his laboratory will be extracting DNA from sediment in the Denisova Cave floors to determine "just when Neandertals were there, when Denisovans were there and when both were there together."
The dream that scientists could document such interactions in the prehistory of humankind "used to seem impossible," Reich says. "But now we are getting to witness the dream."

© 2018 Scientific American, A Division Of Springer Nature America, Inc. All Rights Reserved..
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    Trust My Science / 25 août 2018
    Un poulain vieux de 40'000 ans retrouvé en parfait état de conservation dans le pergélisol sibérien
    • Thomas Boisson
    Якутские ученые рассказали о необычной находке - обнаруженном в вечной мерзлоте жеребенке ленской лошади (Equus lenensis), вымершей примерно в то же время, что и мамонты.

Le gel permanent du pergélisol constitue un milieu de préservation idéal pour de nombreux organismes fossiles. Au-delà des micro-organismes, des insectes et des petits mammifères couramment retrouvés piégés dans ces terres glacées, il arrive plus rarement que les scientifiques découvrent des animaux de plus grande taille. C'est notamment le cas d'un poulain vieux de 40'000 ans et extrêmement bien préservé, retrouvé récemment dans le pergélisol sibérien.
Excavé depuis le cratère sibérien de Batagaika - également appelé la « Porte des Profondeurs » - et incroyablement bien conservé, ce poulain est mort au cours du Paléolithique supérieur, entre 30'000 et 40'000 ans avant le présent. Découvert par des habitants locaux, le corps a été déterré par des scientifiques japonais et russes, puis ramené au Musée Mammoth de l'université fédérale de Yakutsk. « C'est la toute première fois qu'un cheval préhistorique aussi jeune et dans un tel (incroyable) état de préservation est découvert » affirme Semyon Grigoryev, directeur du laboratoire du musée. L'animal était âgé de 2 ou 3 mois au moment de sa mort. Il présente une hauteur aux épaules de 98 cm, avec une robe, une crinière, une queue et des sabots intacts. Même ses organes internes ont été préservés par le pergélisol.
L'espèce du poulain, selon les scientifiques, est génétiquement différente de celle vivant actuellement dans la région de Yakutia. C'était un Equus lenensis (aussi connu sous le nom de cheval de Lena) ; ils parcouraient la région dans le Pléistocène supérieur. L'espèce est désormais éteinte et les connaissances acquises à leur sujet proviennent de nombreux restes momifiés présents dans le pergélisol.
Les scientifiques ont prélevé des échantillons de poils, de liquides, de fluides biologiques et de sol alentour afin de conduire des analyses plus approfondies, incluant une autopsie complète pour déterminer la cause de la mort.
Aucune trace de blessure n'a été trouvée sur le corps. « Les experts de l'expédition suggèrent que le poulain aurait été mort noyé ou étouffé en se retrouvant coincé dans un piège naturel » explique Grigory Savvinov, biologiste à l'université de Yakutsk.
L'autopsie devrait également révéler les conditions de vie de l'animal. Les chercheurs envisagent notamment d'examiner le contenu de son estomac pour connaître ses habitudes alimentaires. En plus du poulain, un squelette de mammouth, avec ses tissus mous et correctement préservé, a également été retrouvé.
Ces découvertes mettent en lumière le stupéfiant pouvoir conservateur du pergélisol ; plus tôt cette année, des scientifiques avaient aussi excavé le corps d'un lionceau extrêmement bien préservé, si jeune qu'il ne possédait pas encore de dents.

© 2018 Trust My Science. All rights reserved.
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    EurekAlert / 27-Aug-2018
    Samara Polytech geologists discovered the fullest skull of Wetlugasaurus
    Sensational discovery was made within a joint scientific expedition.
    Геологи обнаружили в Самарской области самый полный в мире череп ветлугазавра - земноводного, вымершего в раннем триасовом периоде почти 250 млн лет назад.

This June the staff of the "Geology and Geophysics" Department of Samara Polytech took part in a scientific expedition of the Triassic and Jurassic deposits in the southeast of the Samara region.
One of the findings, made with the participation of the Flagship University scientists, was the skull of a Wetlugasaurus. Then it was just a piece of rock with bones protruding from it and it was difficult to identify anything valuable. In the process of studying the skull, it was prepared from the palate side. The teeth and internal nasal apertures - the choanae - became clearly visible.
"Experts of the leading paleontological institute of the Russian Academy of Sciences (Moscow) conducted a detailed assessment of the findings", - says the senior lecturer of
"Geology and Geophysics" Department Alyona Morova. She added that that they were lucky to find the fullest skull of a Wetlugasaurus in the world. Alyona also said that the news was completely unexpected for the scientists.
The expedition was held with the support and participation of the Paleontological Institute of the Russian Academy of Sciences, Samara Regional Museum of Local History named after P.V.Alabin, Samara Paleontological Society, Togliatti Local History Museum, Institute of Ecology of the Volga Basin of the Russian Academy of Sciences. The expedition was headed by Igor Novikov, a leading researcher at the Paleogerpetology Laboratory of the Paleontological Institute of the Russian Academy of Sciences.
Polytech scientists were also lucky to make another unusual discovery - the remains of the postcranial skeleton (more than 170 fragments) of one specimen of Labyrinthodont. In addition, they collected zoological materials of modern mammals and herbarium specimens of plants, including several rare and Red Book species.

Copyright © 2018 by the American Association for the Advancement of Science (AAAS).
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    Drone Below / August 28, 2018
    Can Russian "Robo-Bees" Help Grow More Strawberries?
    • By Arseny Kalishnakoff
    В следующем году ученые Томского политехнического университета планируют запустить проект по созданию пчел-роботов. Искусственные пчелы будут гораздо крупнее живых и предназначены для опыления тепличных растений.

A large amount of our food, including almonds and tomatoes, must be pollinated by bees in order to grow. As bees in the wild struggle with a steep decline in numbers, Russian scientists offer robotic pollinators as a viable substitute.
Bees in the wild are facing grave threats to their existence, and while some of the reasons include pesticides and poor nutrition, the mystery has not been completely solved. Today, most farmers have to buy or rent bee colonies, which contributes to a rise in food prices, according to the U.S. Bee Informed Partnership. American beekeepers have lost an estimated 40 percent of their managed honeybee colonies.
Russian scientists at the Tomsk Polytechnic University (TPU) now offer an alternative: robo-bees. Researchers plan to launch the project in 2019, and the size of the prototypes will be at least seven times bigger than real bees, which means that they'll be the size of a human palm.
For greenhouse use only
According to Alexey Yakovlev, the head of TPU's School of Engineering, artificial bees will be especially beneficial for strawberry and other plants that grow in greenhouses all year round. "We plan to develop the robo-bees, algorithms and software, as well as optical systems and image recognition methods for accurate positioning," Yakovlev said. Creating the first batch of 100 flying robots will cost around $1.4 million.
"For year-round pollination in large greenhouses farmers use bumblebees," Yakovlev said "One bumblebee family costs about $500. In winter, they fly in infrared light, which simulates solar heat, but in spring the whole bumblebee family can escape. This, of course, is an economic loss."
The robots, of course, will work non-stop and will never leave.
Artificial bees, however, will not solve the problem of the species facing possible extinction, said Yakovlev. "We will use robo-bees only in greenhouses, outside their natural habitat." Apple, cherry and other produce growers, however, also use bees in open spaces. Almond growers in the U.S., for example, are paying around $200 for a hive of bees, while blueberry growers pay $110 per hive, and apple growers pay around $70.
Some famers and agricultural companies are considering pollination with alternative species. According to experts, there are other important pollinating creatures, such as bats, flies and mosquitos.
When will robo-bees fly?
Efforts to create an artificial alternative to bees hasn't yet been successful. In 2017, Eijiro Miyako, a researcher at Japan's National Institute of Advanced Industrial Science and Technology, developed a drone to deliver pollen between flowers.
The bottom is covered in horsehair and coated in a special sticky gel. When the drone flies onto a flower, pollen grains stick lightly to the gel, and then rub off on the next flower visited. In experiments, the drone was able to cross-pollinate Japanese lilies. The soft, flexible animal hairs did not damage the stamens or pistils when the drone landed on the flowers.
Miyako's team, however, is still working on developing autonomous drones that could help farmers. GPS, high-resolution cameras and artificial intelligence will be required for the drones to independently track their way between flowers, and land on them correctly.
There are other inspiring developments. Researchers at Harvard University developed a RoboBee that weighs less than one-tenth of a gram. It's equipped with smart sensors that respond to their environment, mimicking the eye function of real bees.
The Charles Stark Draper Laboratory in Cambridge, Massachusetts is working on DragonflEYE, which could be used for guided pollination. Finally, in March, Walmart filed a patent for drone pollinators.
These prototypes, however, are not yet advanced enough for mass pollination, and much more time and research is needed before the first high-tech colony of robo-bees will hit the fields.

Copyright © 2017 by the American Association for the Advancement of Science (AAAS).
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    Popular Mechanics / Aug 28, 2018
    Rare 300-Year-Old "Beard Tax" Coin Discovered in Russia
    Only the second known to exist.
    Псковские археологи обнаружили в одном из кладов «бородовую копейку» 1699 года - жетон, выдававшийся после уплаты введенного Петром I налога на бороду. После отмены налога большинство таких монет были переплавлены, поэтому это лишь второй сохранившийся экземпляр.

In 1698, Tsar Peter the Great of Russia, as he would come to be know, was waging a war on beards. In an attempt to modernize his empire and make it more like the west after spending years exploring Europe in disguise, Peter instituted a tax on facial hair. You could avoid it by shaving, but if you opted to pay the tax, you would receive a token to verify your beard as legal, and an especially rare version of one of these tokens has recently been found.
The coin was discovered by archeologists at the Pskov Archeological Center, according to The Daily Mail, who only found the coin in question recently while digging through a cache of coins found in a dig from 2016. This specific coin, a 'beard kopek' from 1699 is particularly notable and rare as it was issued to peasants, who paid a much smaller tax to preserve their beards than nobility, and received a copper coin as proof of payment, as opposed to a silver one. This newly discovered beard kopek is only the second known to still be in existence.
"Nobody would dare to name its price on this," senior scientist of the Pskov Archaeological Centre Tatiana Ershova, told The Mail. "It is truly a unique find."
Peter's policy of taxing beards, extreme as it may seem, was actually a compromise after the Russian Orthodox church pushed back on his initial decree that there be no beards at all. The tax persisted until 1772 after which many of the tokens were melted down so their metal could be used in other currency. Although it seems that at least two men held onto their coins along with their beards.

© 2018 Hearst Communications, Inc. All Rights Reserved.
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    Space / August 29, 2018
    Prospecting on the Moon: Russia, Europe to Hunt for Lunar Ice
    • By Leonard David
    Европейское космическое агентство (ESA) и Россия ведут совместную работу по разработке технологий и инструментов для проведения буровых работ на Луне с целью дальнейшего поиска и изучения лунных ресурсов, в частности, водяного льда.

The European Space Agency (ESA) and Russia are working together to investigate the moon's resources - specifically, water ice and other volatiles at the lunar poles.
ESA is developing a drilling and sample-analysis payload called the ePackage for Resource Observation and in-Situ Prospecting for Exploration, Commercial Exploitation and Transportation (PROSPECT), which will fly to the moon aboard Russia's Luna 27 mission in the 2022-2023 time frame.
PROSPECT aims to assess potential resources on the moon and help prepare technologies that may be used to extract these resources in the future, ESA officials have said. The project will enter its detailed design phase, known as Phase C, at the start of 2019.
On Aug. 10, ESA released an "announcement of opportunity" for membership in the PROSPECT science team. The opportunity is available to researchers working in ESA member states.
The Luna 27 mission is being orchestrated by Russia's federal space agency, Roscosmos. Luna 27 features a lander that's expected to touch down at then South Pole-Aitken basin, an unexplored area on the far side of the moon.
Assessing resources
PROSPECT's drill, known as ProSEED, will nallow the payload to snag subsurface samples, which are expected to contain water ice and other chemicals that can become trapped in the frigid South Pole-Aitken basin. Subsurface temperatures there typically reach minus 240 degrees Fahrenheit ( minus 150 degrees Celsius) and can get lower than minus 330 degrees F (minus 200 degrees C) in some areas.
These samples will then be passed to an onboard chemical laboratory dubbed ProSPA and heated to temperatures of up to 1,830 degrees F (1,000 degrees C) to extract cold-trapped volatiles. This will test processes that could be applied for resource extraction in the future, ESA officials hav said. (A volatile is a substance that changes readily from solid or liquid to a vapor.)
Cold-trapped volatiles at the lunar poles are potential resources for human exploration and provide a record of volatiles in the inner solar system. However, scientists don't understand much about rthe origins, distribution, abundance or extractability of these materials, or the processes that put volatiles in place within the Earth-moon system.
Global effort
PROSPECT is part of a global effort to coordinate prospecting activities at the lunar poles, where extreme-cold conditions can trap water ice. Space exploration planners see these resources as potentially enabling sustainable space exploration.
Luna 27 is part of a grander roster of moon orbiters, landers, rovers and return-sample spacecraft planned by Roscosmos.
The Russian space agency reportedly aims to launch an earlier mission, Luna 25, very soon, perhaps next year. ESA's contribution to Luna 25 includes PILOT-D, a demonstrator "terrain-relative navigation" system. This will act as a precursor to PILOT, which is the navigation and hazard detection and avoidance system included on Luna 27.
Also in the works are Luna 26 in 2022, Luna 27 in 2022-2023, Luna 28 in 2024 and Lunas 29-31 in 2026.

Copyright © 2018 All Rights Reserved.
* * *
    Ulyces / 29/08/2018
    Des astronomes découvrent une petite galaxie avec un gros trou noir au centre
    • Par Malaurie Chokoualé
    Сотрудники Государственного астрономического института им. П.К.Штернберга МГУ совместно с зарубежными коллегами обнаружили сверхмассивную черную дыру в сверхкомпактной галактике Fornax UCD3.

Une équipe de chercheurs de l'Institut astronomique Sternberg de Moscou a découvert un trou noir supermassif caché dans un endroit inhabituel : le centre de l'une des plus petites galaxies connues, Fornax UCD3. Les chercheurs russes ont travaillé en collaboration avec des scientifiques du monde entier, et leurs résultats ont été publiés dans les Monthly Notices of the Royal Astronomical Society (MNRAS) le 14 août dernier.
Fornax UCD3 est une galaxie naine ultra-compacte (très dense), ce qui rend encore plus surprenant le fait de trouver un gros trou noir en son sein. En utilisant les données du spectrographe infrarouge SINFONI, les chercheurs ont pu estimer que la masse la plus probable de ce trou noir est d'environ 3,5 millions de masses solaires. Soit environ 4 % de la masse totale de la galaxie. En comparaison, Sagittarius A*, le trou noir supermassif au cœur de la Voie lactée, pèserait 4 millions de masses solaires.
Il s'agit du quatrième trou noir découvert dans une galaxie naine ultra-compacte. En 2013 par exemple, des scientifiques avaient découvert une autre galaxie naine ultra-compacte à 54 millions d'années-lumière de la Terre, M60-UCD1, qui renferme également un trou noir en son centre et qui, avec 20 millions de masses solaires, occupe près de 15 % de la masse totale de cette galaxie. Le trou noir nouvellement découvert semble donc bien petit en comparaison mais reste toujours aussi surprenant. Dans les grandes galaxies, la masse du trou noir central est en moyenne inférieure à 1 % de la masse totale.
Les astronomes cherchent toujours à comprendre ce phénomène : un si grand trou noir dans un si petit objet. Il existe cependant une hypothèse qui remporte pour l'instant tous les suffrages. Ces galaxies naines étaient auparavant plus grandes, mais elles seraient entrées en collision avec des galaxies plus grandes encore. Ces galaxies denses seraient en fait les restes de grandes galaxies qui auraient été déchirées suite à des collisions galactiques. Voici une théorie que les chercheurs de l'Institut astronomique Sternberg entendent bien vérifier.

* * *
    EurekAlert / 30-Aug-2018
    Psycholinguists build eye-tracking database on reading in Russian
    При чтении глаза человека делают «скачки» от слова к слову с короткими остановками, во время которых обрабатывается информация. Принципиальных различий у процесса чтения на разных языках нет, но есть особенности. Ученые из ВШЭ, СПбГУ и Потсдамского университета составили базу данных движений глаз при чтении на русском языке. Результаты исследования могут быть использованы не только в лингвистике, но и при коррекции расстройств речи.

Researchers from the Higher School of Economics, St. Petersburg State University, and the University of Potsdam have created the first ever database comprised of eye-tracking data collected during reading in Russian. The results are openly available and can be used not only in linguistics, but also in the diagnosis and correction of speech disorders, for example. The research was published in the journal Behavior Research Methods.
It is well known that while reading, the eyes jump from word to word with short, roughly 220 ms, fixations. Visual information is processed only during fixations. If a word is short or predictable, the eye recognizes it using peripheral vision and skips it, and when reading in alphabetic languages, the eyes skip nearly 30% of words. What's interesting is that in different languages, reading sentences containing the exact same meaning takes a similar amount of time. Texts in a language like Finnish, however, require many short fixations, but in Chinese, there are fewer fixations that last for longer.
The latest psycholinguistic research has shown that the process of reading in different languages does not differ fundamentally. Researchers are nonetheless interested in the characteristics of individual languages. The special properties of eye movements while reading texts in Russian has not been studied before.
"Until now we did not know anything about reading in Russian, even though it is the sixth most widely spoken language in the world. This is why we carried out this basic, yet necessary, work. We took a set of different sentences from existing texts and recorded how native Russian speakers read them," explains Anna Laurinavichyute, a research fellow in the HSE Centre for Language and the Brain. "This is a benchmark for comparison with other languages, on the one hand, and on the other for comparison with children who are just learning to read, Russian Sign Language speakers, bilinguals, the elderly, and patients with aphasia (a speech disorder caused by stroke or head trauma)".
To carry out the experiment, researchers used an eye tracker that can record 1,000 frames per second. The 96 subjects read the same set of sentences randomly chosen from the Russian National Corpus, which is the most representative online database of Russian texts used by linguists. It was important for the researchers to observe how reading speed changes depending on a word's characteristics. This is why the sentences were annotated for word's stress, part of speech, polysemy, usage frequency, length, and predictability.
The database can also be used to study how information is perceived in different languages. For example, the results of the study confirm the hypothesis that verbs are read more slowly than nouns are. And in this particular case, the reason does not have to do with the length of the words, their predictability, or other parameters. When encountering a noun the reader has to correlate a word and an object, but things are more complicated with verbs. First one has to understand what action this word is signifying before remembering who or what is performing the action. Only then does the reader determine if this action has an object, and if it does then in exactly which case the object is used.
Eye-tracking data has great potential. By knowing how a healthy individual reads, a system can be created to diagnose and correct dyslexia or to help regain speech after a head injury. Another area where this could be useful is in determining one's fluency in Russian by observing eye movement while reading. Linguists abroad are carrying out projects like this.

Copyright © 2018 by the American Association for the Advancement of Science (AAAS).
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