Российская наука и мир (дайджест) - Ноябрь 2018 г.

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Российская наука и мир
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    Centre d'Informations Internet de Chine / 01.11.2018
    Une expédition sino-russe a permis de collecter de nombreuses données sur l'Arctique
    21 октября завершилась 2-я российско-китайская арктическая экспедиция. За полтора месяца ученые провели исследования в области океанической геологии, гидрометеорологии, химии и биологии.

Une expédition conjointe entre la Chine et la Russie conclue récemment dans l'Arctique a permis une compréhension plus complète et systématique de l'océan Arctique, qui apportera un soutien scientifique au développement d'une « Route de la Soie polaire », ont annoncé mardi des scientifiques des deux pays.
11 chercheurs chinois et 19 Russes ont participé à la deuxième expédition sino-russe dans l'Arctique qui a débuté le 6 septembre dans le port de Vladivostok (est de la Russie). Après avoir surmonté des conditions météorologiques extrêmes et parcouru 12 000 kilomètres, ils sont rentrés au port de Petropavlovsk-Kamchatsky le 21 octobre.
Cette expédition de 46 jours a été organisée conjointement par le laboratoire national pilote pour les sciences et technologies marines, basé à Qingdao, dans la province du Shandong, et par l'Institut océanologique du Pacifique de l'Académie russe des sciences.
Des scientifiques des deux pays ont mené des recherches multidisciplinaires au cours de l'expédition, notamment en matière de géologie des océans, d'hydrométéorologie, de chimie et de biodiversité, et ont récupéré une multitude de spécimens et de données provenant de l'atmosphère, de l'eau de mer et des sédiments.
« Tous ces éléments fournissent des bases pour étudier l'environnement océanique, la biologie, l'écologie et les changements climatiques », a déclaré Hu Limin, scientifique en chef de l'expédition du côté chinois.
M. Hu a indiqué que l'expédition avait recueilli des données sur l'hydrométéorologie le long du Passage du Nord-Est, une route de navigation reliant le nord-est de l'Asie à l'Europe de l'Ouest.
En juillet 2017, la Russie et la Chine ont convenu de mener des projets de coopération sur la Route maritime du Nord et de construire conjointement une Route de la Soie polaire. La Route de la Soie polaire, traversant l'Arctique, est considérée comme le troisième arc de l'initiative de « La Ceinture et la Route », ajoutant une autre route maritime allant au-delà de la mer de Chine méridionale, de l'océan Indien, de la côte africaine de la mer Méditerranée et du sud de l'océan Pacifique.
Un profileur optique mis au point par le laboratoire de Qingdao a joué un rôle important dans l'observation du passage du Nord-Est et a obtenu des données de première main sur le brouillard, la neige et les nuages bas lors de changements climatiques rapides, a fait savoir Zhao Jinping, scientifique expérimenté spécialisé dans les études sur l'Arctique, qui était également impliqué dans cette expédition.
Anatolii Astakhov, directeur adjoint de l'Institut océanologique du Pacifique de Russie, a déclaré que la Route maritime du Nord présente un intérêt pour les deux pays. Il a indiqué que les spécimens et les données seraient acheminés vers les instituts de recherche des deux pays pour une étude plus approfondie, ajoutant qu'il espérait que les résultats de la recherche seraient publiés dans les meilleurs journaux scientifiques.
La première expédition sino-russe dans l'Arctique a eu lieu en 2016, et le laboratoire de Qingdao a signé il y a un mois une lettre d'intention de coopération avec l'Institut d'océanologie P.P. Shirshov de l'Académie des sciences de Russie.
La coopération avec des scientifiques russes fait partie des efforts du laboratoire de Qingdao pour approfondir la coopération internationale et développer un réseau mondial d'innovation, a déclaré Pan Kehou, secrétaire général du comité universitaire du laboratoire de Qingdao.
Le laboratoire travaille actuellement en partenariat avec les plus grandes forces de recherche océanographique aux Etats-Unis, en Australie et en Allemagne afin de créer des centres de recherche communs, a noté M. Pan.

Copyright © China Internet Information Center. All Rights Reserved.
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    Phys.Org / November 1, 2018
    Machine learning improves accuracy of particle identification at LHC
    Сотрудники Высшей школы экономики разработали новый метод на основе машинного обучения, позволяющий с высокой точностью идентифицировать разные типы фотонов на Большом адронном коллайдере.

Scientists from the Higher School of Economics have developed a method that allows physicists at the Large Hadron Collider (LHC) to separate between various types of elementary particles with a high degree of accuracy. The results were published in the Journal of Physics.
One of major unsolved problems of modern physics is the predominance of matter over antimatter in the universe. They both formed within a second after the Big Bang, in presumably equal fractions, and physicists are trying to understand where antimatter has disappeared to. Back in 1966, Russian scientist Andrei Sakharov suggested that the imbalance between matter and antimatter appeared as a result of CP violation, i.e., an asymmetry between particles and antiparticles. Thus, only particles remained after their annihilation (mutual destruction) of resulting unbalanced contributions.
The Large Hadron Collider beauty experiment (LHCb) studies unstable particles called B-mesons. Their decays demonstrate the clearest asymmetry between matter and antimatter. The LHCb consists of several specialised detectors, specifically, calorimeters to measure the energy of neutral particles. Calorimeters also identify different types of particles. These are done by search and analysis of corresponding clusters of energy deposition. It is, however, not easy to separate signals from two types of photons-primary photons and photons from energetic π0 meson decay. HSE scientists developed a method that to classify these two with high accuracy.
The authors of the study applied artificial neural networks and gradient boosting (a machine-learning algorithm) to classify energies collected in the individual cells of the energy cluster. "We took a five-by-five matrix with a centre at the calorimeter cell with the largest energy," says Fedor Ratnikov, one of the study's authors and a leading researcher in the HSE Laboratory of Methods for Big Data Analysis. "Instead of analysing the special characteristics constructed from raw energies in cluster cells, we pass these raw energies directly to the algorithm for analysis. The machine was able to make sense of the data better than a person."
Compared with the previous method of data pre-processing, the new machine-learning-based method has quadrupled quality metrics for the identification of particles on the calorimeter. The algorithm improved the classification quality from 0.89 to 0.97; the higher this figure is, the better the classifier works. With a 98 percent effectiveness rate of initial photon identification, the new approach has lowered the false photon identification rate from 60 percent to 30 percent.
The proposed method is unique in that it allows for elementary particles to be identified without initially studying the characteristics of the cluster being analysed. "We pass the data to machine learning in the hope that the algorithm finds correlations we might not have considered. The approach obviously worked out in this case," Fedor Ratnikov concludes.

© Phys.org 2003-2018, Science X network.
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    The Things / Nov 07, 2018
    Russian Scientists Discover A New Bacteria To Handle Nuclear Waste Concerns
    • By Maja Gjorgjioska
    Ученые из Института физической химии и электрохимии имени А.Н.Фрумкина РАН и Федерального исследовательского центра биотехнологии РАН обнаружили бактерии, способные при определенных условиях снижать активность радионуклидов и ограничивать их распространение. С помощью этих бактерий можно будет создавать нечто вроде барьера для захоронений радиоактивных отходов.

Some Russian researchers from the Frumkin Institute of Physical Chemistry, along with the Russian Academy of Sciences' Federal Research Center for Biotechnology recently isolated some microorganisms that can actually be used to neutralize the environment from any liquid nuclear waste.
The researchers in question were doing a microbiological study on the water at the deep radiation burial site in Seversk, named Seversky, in Siberia when they came across this new discovery. This site has liquid nuclear waste that comes from the Siberian Chemical Combine, where the low enriched uranium that's used for nuclear fuel is stored, supplied and reprocessed. The scientists also recently published their discovery in a Russian scientific journal named Radioactive Waste. According to them, this bacteria can easily convert the radionuclide ions, even the ones that are found in uranium and plutonium, and turn it into sedentary forms. This way, it prevents the spreading of any dangerous radiation to any surrounding environment, and therefore, neutralizing it. And thanks to plenty of experiments in the lab, these scientists were also able to find out the exact conditions that the bacteria needs to do its magic.
This is the very first step that scientists have found in their way of making a biogeochemical barrier for radionuclides, that can be then used in deep burial locations that contain liquid nuclear waste. Research of this type has been done since the 1980s, with scientists all over the world trying to find ways to limit the effects that nuclear waste has on the environment. This discovery, along with a method that would be able to generate nuclear power in a safe manner, there would be absolutely no need for wars about who is going to control the sources for fossil fuels.
And with all of these scientific announcements, that could potentially cause a major economic disruption all over the globe, Russia is clearly showing that they are more than capable of ending the economic system which is based on scarcity, in the western world. Additionally, the alliance between Russia, India, and China, also known as the RIC Alliance, has already moved away from the fiat dollar, and now are rapidly unloading large amounts of US treasury bonds.

Copyright © 2018 TheThings.com.
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    Phys.Org / November 9th, 2018
    Kazan University physicists first in the world to observe quantum state of magnons at room temperature
    The phenomenon is analogous to superfluidity of atoms or superconductivity of electrons.
    Сверхтекучесть - способность вещества в жидком состоянии при очень низких температурах протекать без трения даже через самые узкие капилляры. Спиновой (магнитной) сверхтекучестью называется явление, при котором без трения переносится намагниченность - также при почти абсолютном нуле температуры. Российские физики впервые получили спиновую сверхтекучесть при комнатной температуре, создав бозе-эйнштейновскую конденсацию квазичастиц магнонов на пленках иттриевого феррит-граната.

Murat Tagirov's group at the Department of Quantum Electronics and Radio Spectroscopy was able to create Bose-Einstein condensation of magnons and spin superfluidity at room temperature using films of yttrium iron garnet. The discovery was made by Yury Bunkov and his colleagues within a project funded by the Russian Science Foundation. A preprint of the paper is available here.
Superfluidity was first observed by Pyotr Kapitsa in 4He, a feat for which he later received a Nobel Prize in physics. Superfluidity in 3He was also found by other researchers. In the 1980s, a group of Soviet scientists, including Yury Bunkov, discovered spin superconductivity under near-absolute zero temperatures. They received a Russian State Award in 1993 and a Fritz London Memorial Prize in 2008.
Dr. Bunkov comments, "Until now, superconductivity or superfluidity were not observed at room temperatures. However, we found spin superfluidity in yttrium iron garnet films under those conditions. Its properties are very much like those of 3He. To yield spin superfluidity, we had to elevate the density of magnons to the state where they would create a coherent state, or, in other words, to create Bose-Einstein condensation of magnons. A very important part of our achievement is that condensation was achieved for standing spin waves; it had been earlier induced for coherent spin waves, but it's very difficult to utilize because it doesn't interact with magnetic fields."
Yttrium iron garnet fields are currently used for magnetic electronics. With this discovery of magnonic superfluidity at room temperatures it can become "supermagnonics", says Bunkov. Devices with magnon components can become miniaturized and more sensitive. One such example is SQUID, superconducting quantum interference device, used in industry and medicine.
This new result may also serve for quantum computing and energy saving technologies for existing computers and supercomputers.

© Phys.org 2003-2018, Science X network.
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    New York Times / Nov. 12, 2018
    A 'Time Capsule' for Scientists, Courtesy of Peter the Great
    A Russian zoological museum filled with centuries-old specimens finds renewed relevance in the age of genetics.
    • By James Hill
    Репортаж из Зоологического музея Зоологического института РАН, чьи богатейшие коллекции являются бесценным источником генетической информации о животном мире.

ST. PETERSBURG, Russia - Standing alone, a few minutes before the doors were to open at the Zoological Museum of the Zoological Institute of the Russian Academy of Sciences, Alexei Tikhonov gazed at Masha, a 30,000-year-old baby mammoth that he brought here from a Siberian riverbank thirty years ago.
Masha, one of the museum's star attractions, rests with hundreds of other encased exhibits in one of the largest public collections of zoological specimens in the world. The cabinets, conceived in Frankfurt at the end of the 19th century, and the Czarist hunting trophies here exude an old-fashioned, even romantic air. But Dr. Tikhonov, director of the museum, is not too concerned. Sometimes he yearns for plasma panels and the modern gadgetry that many other museums use to inform visitors. But he has limited funds to modernize the museum, and prefers to spend that money buying new collections and supporting scientific fieldwork.
This collection, first formed from acquisitions made by Peter the Great three centuries ago, is nonetheless taking on a new, more vital role. As the animal world becomes increasingly threatened, these exhibits are helping to unlock genetic information and precious clues to aid species survival.
The museum, like other great natural history museums, is "a time capsule for organisms," said Ross MacPhee, curator of mammals at the American Museum of Natural History in New York.
"For certain kinds of studies, such as species endangerment and the loss of genetic diversity, this is turning out to be increasingly important," he added. "Natural history museums are literally the only places where you will find good quality remains."
Down the hall from Masha, in a cabinet holding birds of prey, are two California condors. Probably the oldest specimens in the world, they were brought to St. Petersburg by a collector in 1851 from Fort Ross, originally a Russian outpost in California.
When researchers at Penn State began searching for genetic information on the scarce population of California condors in the United States - currently there are less than 500 birds - the university reached out to St. Petersburg for help. A few months later, a feather from each bird was dispatched to university scientists for study.
Genetic material is increasingly stored by zoological museums and institutions in frozen samples. But the information to be gathered from dry specimens is also useful, said Mikhail Kalyakin, an ornithologist and the director of the Zoological Museum at Lomonosov State University in Moscow.
To ascertain the fate of the slender billed curlew, for example, ornithologists analyzed DNA clues found in the skin and intestines of museum specimens to pinpoint the species' traditional habitats, helping to guide the search for remaining birds.
"As species come under threat," Dr. Tikhonov said, "we hope that in the future, due to these genetic efforts and new methods, it will be possible to restore these species." But restoring the woolly mammoth, an oft-cited possibility, is another proposition altogether.
The notion is that the mammoth genome could be recovered, at least in part, and introduced somehow into an elephant embryo. But the science behind such a "de-extinction" would be bogglingly complex.
Dr. Tikhonov, one of the world's leading experts on mammoths, is quick to point out the complications.
"We cannot, for the moment, reconstruct a mammoth without making hundreds or thousands of mistakes," he said.
For one thing, ancient DNA is heavily fragmented, noted Dr. Daniel C. Fisher, director of the University of Michigan's Museum of Paleontology.
"For these and other reasons, the whole notion of simply recovering ancient DNA and plugging it into living cells to generate zygotes is profoundly impractical," he said. The creation of hybrid mammoths is not only a technical issue. Where would these giant mammals live in a modern world, save perhaps the Siberian tundra? How would they affect existing ecosystems?
For the moment, this debate remains hypothetical, but few doubt that the technology to create hybrid mammoths will be realized at some point. "It is a case of human ingenuity outskating ethical concerns," said Dr. MacPhee.
Back in the halls of the museum, Dr. Tikhonov soon found himself happily swamped by schoolchildren. "The first role of the museum is educational," he shouted over the heads of the crowd.
The Zoological Museum has 300,000 visitors per year, and he was expecting as many as 7,000 visitors that day. By early afternoon, the guides were already exhausted, but one of them, Polina Kenunnen, managed a smile when asked to take yet another group of young children for a tour.
"On the internet, there is often silliness," she said while marching up the stairs toward the skeleton of a blue whale and the bust of Charles Darwin. "But here we can really show and tell things as they are."

© 2018 The New York Times Company.
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    Breaking Israel News / November 20, 2018
    TAU Scientists Find Tadpole-Shaped Galaxy Swallowed by Neighbor
    • By Judy Siegel-Itzkovich
    Израильско-американско-российская группа астрономов обнаружила на расстоянии 300 млн световых лет от Земли галактику, формой напоминающую головастика. По мнению ученых, «головастик» протяженностью около миллиона световых лет образовался в результате разрушения и притяжения двумя соседними галактиками третьей, причем процесс слияния еще продолжается.

Astronomers at Tel Aviv University's Wise Observatory outside Mitzpe Ramon in the Negev have discovered evidence of a galaxy's being gobbled up by its neighbors. They identified a heavenly body in the shape of a tadpole with an enormous tail about 500,000 light-years long and some 300 million light-years away from Earth. They said the "tadpole," which had not been discovered until now because it shines in a very pale light, is composed of the remains of a dwarf galaxy created by swallowing two large nearby galaxies. Their article has just been published in the Monthly Notices of the Royal Astronomical Society.
The researchers, led by Dr. Noah Brosch of the School of Physics and Astronomy, identified an unknown celestial body about 300 million light-years away. The "torso" has an elliptical 'head' with two galaxies in its center. They believe this is a new and concrete demonstration of a fascinating process in the universe - the absorption of a dwarf galaxy by the two large galaxies in its vicinity.
The study was conducted in collaboration with scientists at the University of California at Los Angeles (UCLA) and the Russian Academy of Sciences.
"We're looking for 'action' in the sky," explained Brosch. "We're watching galaxies and nearby areas to detect evidence of change. Is the galaxy growing or shrinking? Is it interacting with other galaxies? Among other things, we observe dense clusters of galaxies, assuming that when the galaxies are close together, there will be more interactions between them," added Brosch.
"This kind of dense galaxy group is called Hickson Compact Group (HCG), named after Canadian astronomer Paul Hickson, who identified them in 1982. Unlike galaxy clusters that include many thousands of galaxies, HCG groups include only a few galaxies, making it relatively easy for us to identify and understand interactions between them. The group of galaxies observed in this study is called HCG 98," he said.
HCG 98 is a dense group of four galaxies, located 300 million light-years away. In comparison, the visible end of the universe is about 14 billion light-years away, so the HCG 98 group is actually a relatively close neighbor. In observations and experiments, astronomers used special technology, including a telescope that was acquired about five years ago, and a method of processing that combines many photographs of the same region and allows researchers to distinguish even very pale bodies that cannot be seen in any other way.
These observations of HCG 98 revealed a new and unusual finding - a giant celestial body shaped like a tadpole made up of two ordinary galaxies, followed by an enormous tail," said Brosch, "We think this is concrete evidence of a process that is going on in the universe constantly: the dissolution of dwarf galaxies by larger galaxies. Such an event, which takes about a billion years, occurs when the stars of the dwarf galaxy are attracted by the gravitational force of the large galaxies."
In this case, the head of the tadpole appears to have been created from the stars of the dwarf galaxy, which were close to the two predatory galaxies observed in the center of the head; the giant tail is composed of the remains of farther stars in the disintegrating galaxy. In fact, said concluded Brosch, "our observation has captured the liquidation process in full swing."
Wise Observatory researchers are continuing their large-scale project using the special detection technology for nearly 100 galaxies across the universe.

© Copyright 2013-2018, All Rights Reserved.
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    Motherboard / Nov 20 2018
    Scientists Want to Monitor Space Debris from Warming Russian Arctic
    A MIPT team is building prototype observatories over the coming weeks in Amderma, Nenets Autonomous Region.
    • By Becky Ferreira
    К 2020 г. в российской Арктике планируется создать экспериментальную сеть центров мониторинга околоземных космических объектов. Первый телескоп предполагается разместить в поселке Амдерма в Ненецком автономном округе уже в конце ноября.

The most sophisticated telescopes on Earth are often constructed in extreme landscapes, such as Hawaiian volcano summits or remote Chilean deserts, chosen for their clear view of the stars. Now, scientists are looking to the Russian Arctic as a potential location for new astronomical observatories. In a bittersweet twist, this region may become more accessible to scientific and commercial development as climate change warms and melts the Eurasian North, opening up new shipping lanes that have been too icy to easily traverse before. Plus, the region's long, dark nights and high-latitude coordinates would offer a rare Arctic view of the night sky, and could be a good place to monitor space debris in polar orbits.
To lay the groundwork for potential Arctic observatories, Alexander Rodin, head of the Applied Infrared Spectroscopy Laboratory at Moscow Institute of Physics and Technology (MIPT), is leading an expedition to build and test experimental telescopes in Nenets Autonomous Region over the coming weeks.
It's not clear what impact climate change will have on viewing conditions in the region, Rodin told Motherboard in an email. "However, climate change and increasing accessibility increase general interest to the region by major world players," he said. Rodin hopes to establish Arctic space observation infrastructure in the near future to prepare for the expected rush to develop Russia's polar regions.
The coastal town of Amderma, located about 1,200 miles northeast of Moscow as the crow flies, was selected for this pilot project. Rodin and his colleagues plan to set up temporary instruments there by late November and aim to be taking measurements in December. By 2020, the team hopes to have set up a more permanent operational network of observatories.
"We plan a wide range of experiments, including astro-climate studies, space object observations, and even greenhouse gas monitoring in the region of interest," Rodin said. "As the Russian Arctic has not been seriously considered as a potential area of astronomical observations, comprehensive preliminary studies need to be done."
One of the biggest priorities for the expedition is to assess the region's usefulness for monitoring space debris, which threatens operational spacecraft; the tiny grains erode spacecraft exteriors while larger chunks could cause catastrophic collisions. Decades of spaceflight missions have left an estimated 170 million pieces of space junk in orbit around Earth, including about 30,000 objects that measure more than 10 centimeters (four inches) in diameter.
Scientists around the world are collaborating on the growing space debris problem, but much of the focus has been on busy geostationary orbits above Earth's equatorial regions, where most of the junk is concentrated. Less attention has been paid to the debris building up in polar orbits, and Rodin believes these trajectories need to be more actively monitored.
"Of course, at the moment, geostationary orbit remains the most populated location in the near-Earth space, but this situation may change in the future," he told me, citing forthcoming satellite constellation missions, like Russia's Sfera project.
"We need to be prepared to introduce an international 'road traffic law' for Earth-orbiting satellites, including those on the high-inclination orbits, and to control their observation by all participants."
More broadly, the expedition aims to yield insights into the development of future astronomical observatories in the Russian Arctic. Rodin recently attended an international conference in Naryan-Mar, Nenets, centered on anticipating the effects of climate change on the region's industry, science, and culture.
"There is a common opinion that average temperature will rise in the nearest decades, and the area of perennial ice in the Arctic will dramatically shrink," Rodin said. "However, nobody knows for sure how cloud coverage, haze, atmospheric turbulence, and other parameters important for astronomical observations will change. Thus we need more comprehensive climate research in this key area of our planet."

© 2018 VICE MEDIA LLC.
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    ScienceAlert / 26 Nov 2018
    DNA of The Mysterious 'Siberian Unicorn' Has Been Analysed For The First Time
    • Michelle Starr
    Российские палеонтологи совместно с зарубежными коллегами впервые проанализировали ДНК доисторического носорога эласмотерия (Elasmotherium sibiricum), обитавшего в Евразии в среднем плейстоцене. Выяснилось, что питался эласмотерий исключительно травой, окончательно вымер в конце последнего ледникового периода, а также не являлся близким родственником современных носорогов.

It didn't look much like the dainty unicorns of myth and legend, but the extinct unicorn of Siberia is even more entrancing for palaeontologists.
Now, for the first time, scientists have analysed its DNA - and realised everyone had been wrong about the mysterious beast.
The ancient rhinoceros didn't die off 200,000 years ago, before the last Ice Age - as we previously thought. The strange animals survived much, much longer, only disappearing as recently as 36,000 years ago. In fact, they could have lived alongside modern humans. Moreover, the Siberian unicorn was not, as had been thought, closely related to modern rhinos, but a unique lineage that split from the line that led to modern rhinos over 40 million years ago. Until now, our knowledge of the unicorn (Elasmotherium sibiricum) has been stymied because of the lack of fossil record.
Only a few fragmented bones have been recovered, and apart from revealing the size of the beast - around 3.5 tonnes, the same range as a smaller African elephant - those have been difficult to analyse. For example, part of a skull that was described in a 2016 paper was radiocarbon dated up to 29,000 years ago, but because there was so little collagen, the result was considered unreliable. So an international team of researchers collected 23 Siberian unicorn bone specimens and subjected them to radiocarbon dating, to see if they could recover DNA and find out more about the Siberian unicorn and its time on Earth.
The results were surprising: they were dated to a range of times after the animals were thought to be extinct, with the most recent being between 35,000 to 36,000 years ago. By this time, humans had started populating the steppe of Russia, Kazakhstan, Mongolia and Northern China. But humans likely had nothing to do with the animal's disappearance.
"If we look at timing, it's during a period of climate change, which wasn't extreme, but it did cause a whole bunch of much colder winters that we think really altered the extent of the grassland in the area," Alan Cooper of the Australian Centre for Ancient DNA at the University of Adelaide explained to ScienceAlert.
"We can also see the change in the isotopes in the bones of the animals - you can see and measure the carbon and the nitrogen in the bones and we can see that it was only eating grass."
At around the same time, other animals in the area that ate grass started to switch their diets to herbs, shrubs and whatever other vegetation they could sink their teeth into, but not the Siberian unicorn. It kept on munching on grass, even as, the researchers believe, encroaching permafrost killed it off.
"It looks like this unicorn thing was so specialised to eat grass it couldn't survive," Cooper said.
"Its head was a whopping great big thing, it was kind of extended really really low, sitting right at grass height, so it really doesn't have to lift its head up. There's question of whether it could even lift its head at all! It was highly specialist so once the environment shifted it appears to have died out."
We don't know how big the animal's horn grew, since no horn has ever been found. However, the part of the skull where the horn would have grown has been recovered, with an absolutely massive base. Based on comparisons with living horned animals, the Siberian unicorn's horn could have been up to 1 metre (3.3 feet) in length. Combined with its big, heavy head, this horn could have made reaching higher foliage even more difficult for the ancient rhino. But if its lineage was tens of millions of years old, the species had survived several climate change events already. Exactly why this particular, relatively mild cooling event was the straw that broke the unicorn's back is still a bit of a mystery, and one that will take more research to unravel. But it does constitute a warning we would do well to heed.
"The worrying thing about it is it shows you don't have to have major climate change to have vegetation responses that can wipe out a species - and this is before humans had restricted animals' ranges. Can you imagine what will happen today?" Cooper said.
"That's why people are looking at large grasslands such as Africa. But what about food production? Similar kind of stuff - once these climate changes start getting in the way the environment can have some pretty big impacts and quickly."
The team's research has been published in the journal Nature Ecology & Evolution.

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    Phys.org / November 27, 2018
    Archaeologists find the oldest burials in Ecuador
    Археологи Дальневосточного федерального университета обнаружили в Эквадоре погребения возрастом от 6 до 10 тысяч лет, относящиеся к раннеголоценовой культуре Лас-Вегас.

Archaeologists of the Far Eastern Federal University (FEFU) found three burials of the ancient inhabitants of South America dated from 6 to 10 thousand years ago. The excavations were carried out in Atahualpa сanton, Ecuador. The findings belong to the Las Vegas archeological culture of the Stone Age.
Analysis of artifacts will help scientists understand the development of ancient cultures on the shores of the Pacific Ocean and clarify the origin and development of ancient American civilizations. Research is being jointly conducted by FEFU and Primorsky Polytechnic University in Guayaquil (ESPOL, Ecuador).
Previously, FEFU scientists investigated the famous Neolithic settlement in Real Alto. In 2018, they decided to study an earlier site in order to trace the development of ancient cultures on the Pacific Coast opposite to the Pacific Coast of Russia (Russian Far East).
"The archaeological site of Loma Atahualpa is more archaic than Real Alto, its materials are transitional from the Mesolithic to the Neolithic. We excavated three burials that were probably made at different times. This will make it possible to compare their materials and retrieve the new information on the development of ancient cultures in the period from 10 to 6 thousand years ago," said the Alexander Popov, director of the Educational and Scientific Museum of The School of Humanities of FEFU.
Expedition materials are processed by experts from several countries. The stone tools found were examined at Tohoku University (Japan) for traces of mechanical activity in order to understand how they were used. There were also sent samples for radiocarbon dating.
Simultaneously, anthropologists from The Kunstkamera (Peter the Great Museum of Anthropology and Ethnography, St. Petersburg) and the Institute of the Problems of Northern development, Siberian Branch of the Russian Academy of Sciences (Tyumen, Russia) began to study the morphological features of the human remains found.
"In the course of working with Ecuadorian colleagues, we have learned that our research attracted the obvious attention of scientists. Last year's symposium, which was organized at the Real Alto Museum, was attended by colleagues from the United States, Canada, Brazil, Japan, Poland and other countries. We also cooperate with partners from several European countries and the Russian Academy of Sciences," said Alexander Popov.

© Phys.org 2003-2018, Science X network.
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    United Press International / Nov. 27, 2018
    DNA analysis suggests people migrated from Siberia to Finland 3,500 years ago
    The new research offers a glimpse of human movement across Fennoscandia between 3,500 and 1,500 years ago.
    • By Brooks Hays
    Проанализировав ДНК человеческих останков, найденных в захоронениях возрастом 3500 лет (Кольский полуостров) и 1500 лет (юг Финляндии), немецкие, финские и российские ученые подтвердили генетическую связь между древними финскими и сибирскими популяциями.

For the first time, scientists have used genetic analysis to confirm the link between Finland and Siberia.
The research showed Siberian ancestry migrated from Russia's Kola Peninsula to Finland several thousand years ago. Scientists confirmed the link by comparing DNA from 3,500-year-old bones and teeth recovered from Bolshoy Oleny Island, located along the Kola Peninsula, to DNA from remains excavated from a 1,500-year-old water burial in Finland. The findings - published Tuesday in the journal Nature Communications - offered new insights into the genetic origins of early Finnish settlers.
"Our analyses show that Siberian ancestry entered the Bolshoy population around 4,000 years ago," Thiseas Christos Lamnidis, researcher at the Max-Planck-Institute for the Science of Human History, told UPI. "The first solid evidence of Siberian ancestry is observed 500 years later in the Kola Peninsula, but it is possible that Siberian ancestry was present in Fennoscandia before that time. It is also likely that Siberian ancestry arrived in many waves."
The new research also showed the Saami people, an indigenous people now living in the northern part of Scandinavia, once lived in the southern half of mainland Finland. When scientists compared the DNA collected from the ancient water burial - remains belonging to an Iron Age people living in the Levänluhta region of Western Finland - to the DNA of Saami people, they found a similar genetic profile.
"We tested if each sampled individual from Levänluhta shared more genetic information with a set of worldwide populations than present-day Finns or Saami do," Lamnidis said. "A lack of significant differences in such a comparison indicate that the Levänluhta population is genetically more closely related to the present-day Saami, and less closely related to modern Finns."
The genetic similarity explains the significant concentration of Siberian gene signatures still present in the genome of present day Saami people.
"It is suggested both historically and linguistically that the earlier inhabitants of Finland were Saami groups, while Finnish-speaking groups are said to have arrived in Finland circa 1,000 years ago," Lamnidis said. "This study offers the first genetic evidence of this hypothesis, based on ancient DNA."
But while the new research offers a glimpse of human movement across the region between 3,500 and 1,500 years ago, the peopling of Fennoscandia - the region encompassing Finland, Norway, Sweden and parts of Russia - is still poorly understood.
The authors of the new study acknowledge that more genetic analysis is needed to broaden the story of ancient human migration in the region.
"In our study we show this ancestry to be absent from the Baltics in the Bronze Age, but present in the present-day Estonians, which raises the question of when did the ancestry spread to the Baltics," Lamnidis said. "More ancient DNA studies from Fennoscandia could also help pinpoint when this ancestry first arrived."

Copyright © 2018 United Press International, Inc. All Rights Reserved.
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    Science Daily / November 28, 2018
    Scientists discovered a set of enzymes to create glowing organisms
    Pathway leading to bioluminescence in fungi identified and transferred to another organism - study published in PNAS.
    Российские ученые вместе с коллегами из Великобритании, Испании, Бразилии, Японии и Австрии расшифровали механизм грибной люминесценции. Оказалось, что свечение грибам обеспечивают всего четыре ключевых фермента, которые и вызывают биосинтез люциферина. Причем перенос этих ферментов позволяет сделать светящимся практически любой организм.

In daylight, Neonothopanus nambi is a rather unremarkable brown fungus. But a surprise hides behind the drab façade: at night, the fungus glows ghostly green. Neonothopanus nambi is one of over 100 species of mushrooms that emit light. Aristotle already documented this phenomenon, called bioluminescence, when he described glowing, rotting treebark. Now, scientists have for the first time identified the biochemical pathway that allows bioluminescent fungi to light up. But they went even further: by putting the three genes necessary to generate luminescence into a non-glowing yeast, they created an artificially luminescent eukaryote. Fyodor Kondrashov, professor at the Institute of Science and Technology Austria (IST Austria) was co-author of the study published today in PNAS, which was led by Ilia Yampolsky at the Institute of Bioorganic Chemistry of the Russian Academy of Sciences in Moscow.
Flitting fireflies and glowing mushrooms on the forest floor are among the few things to be seen in a dark night deep in the Brazilian forest. Both behave like living night-lights thanks to the process of bioluminescence, a natural phenomenon by which a substance called luciferin is oxidized with the help of the enzyme luciferase to emit a light. Bioluminescence is found in many species, from glowing worms to deep-sea fish. So far, however, the biochemical pathway that makes luciferin was not understood in any organism except bacteria. This lack of knowledge hampered attempts to make higher organisms, like animals and plants, glow. Now, an international collaboration between twelve different institutions and led by Ilia Yampolsky, with the participation of Fyodor Kondrashov, Louisa Gonzalez Somermeyer and his previous group member Karen Sarkisyan, identified how the eukaryote Neonothopanus nambi glows.
The scientists found the key genes responsible for the bioluminescence of Neonothopanus nambi. Using library screening and genome analysis, the team identified the enzymes that contribute to the synthesis of luciferin. They showed that fungal luciferin, the substrate for the bioluminescence reaction, is only two enzymatic steps away from a well-known metabolite, called caffeic acid, which the fungus generates. Comparing mushrooms that glow with those that don't, Kondrashov's team also uncovered how gene duplication allowed bioluminescence to evolve more than a hundred millions of years ago. Why it evolved is, as yet, unclear, says Kondrashov: "Is bioluminescence beneficial or just a side product? We don't know yet. There are evidences that the glow attracts insects which distribute the spores. But I don't think that's convincing."
Knowing how bioluminescent fungi glow, the researchers then lit up non-bioluminescent eukaryotes. Inserting the gene encoding luciferase in Neonothopanus nambi along with three other genes whose products form the chain that converts the metabolite caffeic acid into the substrate for the reaction, luciferin, into the yeast Pichia pastoris resulted in glowing colonies of yeasts. "We don't supply a chemical that makes the yeast glow. Instead, we supply the enzymes it needs to convert a metabolic product that is already present in the yeast into light," explains Kondrashov.
This discovery could find widespread applications, from tissues that report changes in their physiology by lighting up to creating glowing animals and plants. "If we think of sci-fi scenarios in which glowing plants replace street lights - this is it. This is the breakthrough that can lead to this," Kondrashov concludes, "However, it may take several years until such a plant street light is engineered."

Copyright 2018 ScienceDaily.
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