Российская наука и мир (дайджест) - Май 2020 г.
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2020 г.
Российская наука и мир
(по материалам зарубежной электронной прессы)

январь февраль март апрель май июнь июль август сентябрь октябрь ноябрь декабрь

    Институт биологии гена РАН, Центр вирусологии и биотехнологии «Вектор» и Белгородский государственный университет работают над выведением трансгенных мышей для испытания вакцины и препаратов против COVID-19. Симптоматика и патогенез у них должны быть близки к человеческим, поскольку обычные мыши переносят коронавирусную инфекцию иначе.

Following the recent Coronavirus outbreak, almost three million people have been infected worldwide, whereas the death toll has already passed the 200,000 mark, according to official reports. Meanwhile, a vaccine remains to be found, and classic medications show low efficacy. Under these conditions, it is up to pharmacologists to do their best in the search of novel treatments. However, laboratory studies are limited by the absence of COVID-19 animal models.
Russian scientists from the Institute of Gene Biology of the Russian Academy of Sciences, the State Virology and Biotechnology Research Center "Vector" and Belgorod University are already working on the development of SARS-CoV-2-sensitive mice to be used as a murine model in tests of potential COVID-19 vaccines and drugs, reports the Office of the Chief State Sanitary Inspector.
To create such a line of mice, researchers have formulated a two-step concept, recently described in the open-access, peer-reviewed scholarly journal Research Results and Pharmacology. Firstly, the mice are to be made biologically safe for routine laboratory practice. Secondly, in order for the mice to be efficient for non-clinical trials, they will need to experience symptoms and pathogenesis as human-like as possible. The scientists believe that they have everything necessary to implement this conception and expect the first results as early as June 2020.
"SARS-CoV-2-inoculated mice will have a human-like pathogenesis and symptoms of the COVID-19. The key difference between a new model and the existing ones will be its biological safety - animals will become sensitive to SARS-CoV-2 only after activation in conditions of a virological laboratory. It makes it possible to nullify the contagion risk for the staff working in nurseries and non-specialised laboratories during a pandemic," the team explains.
Already available data shows that there are two key proteins in the human cells, which are involved in the virus entry. First of all, it is the angiotensin-converting enzyme 2 (ACE2), which is the direct and main target of the coronavirus' "corona". Three lines of transgenic mice with the human ACE2 variant have been found to be susceptible to the SARS-CoV, a causative agent of the SARS outbreak in 2003. However, it was shown that, in addition to ACE2, a molecular pathway of coronavirus invasion contains another important link: the enzyme transmembrane protease serine 2 (TMPRSS2). The blocking of TMPRSS2 prevents SARS-CoV-2 entry on the cell culture in vitro.
To obtain mice with human-like COVID-19 symptoms and pathology, the researchers will introduce human ACE2 and TMPRSS2 genes into the murine genome under the mice's own Tmprss2 promoter. Another key decision on the way of creating the new model is to ensure that SARS-CoV-2 sensitivity is inducible only after the introduction of LoxP sites in front of the human ACE2 and TMPRSS2 genes. As a result, human genes in a murine genome will turn on once a crossbreeding with mice expressing Cre-recombinase occurs.
"The main trick here is that this crossbreed will only happen in specialised virological laboratories, which will prevent the novel line of mice from becoming an infection 'reservoir' in ordinary laboratories," say the researchers.

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    В современных лабораториях для ряда исследований используются так называемые микрореакторы - крошечные устройства, позволяющие осуществлять различные химические процессы. Однако микроскопические размеры емкостей затрудняют перемешивание жидкостей и реагентов. Ученые из Университета ИТМО совместно с чешскими коллегами предложили использовать «наномиксер» - кремниевую антенну размером около 200 нанометров, вокруг которой закручивается энергия света.

The tiny domain of microfluidics has opened big horizons in chemistry and pharmaceuticals, allowing creation of "lab on a chip" platforms for experiments and drug development. But as scientists look at processes at ever-smaller length and time scales, the problems of rapidly and efficiently mixing different fluids - in channels far thinner than a human hair - become formidable. That’s made it hard to use these platforms to drill down into some potentially fruitful, high-reaction-rate frontiers of chemical engineering.
Now, in numerical experiments, a team of researchers from Russia and Czechia has proposed a possible solution to the problem: using nanoparticles and the radiation pressure of light to create a "nanomixer" that can rev up otherwise slow diffusion mixing in the channel (Adv. Sci., doi: 10.1002/advs.201903049). The researchers’ calculations suggest that the proposed nanomixer can operate at length scales an order of magnitude smaller than other approaches for mixing on lab-on-chip platforms. And the team believes the system can find use not only in mixing on-chip reagents at very short length and time scales, but also as a system for sorting certain nanoparticles by size.
The mixing problem
The difficulties in mixing different species in a microfluid channel stem largely from basic fluid dynamics. Pushing liquid through an extremely narrow pipe, such as a microfluidic channel, implies laminar, sheet-like flow and a very low Reynolds number. That, in turn, means that viscous forces will tend to dominate, and mixing will take place mainly by diffusion, at super-slow rates.
A number of active mixing approaches have been put on the table for microfluidics, to decrease the so-called mixing length and consequently increase the reaction rates open to experiments. These schemes have included the use of ultrasound and electro- and magnetohydrodynamic systems to shake things up a bit, and thereby more rapidly mix liquids in microfluidic channels.
Laser light, which carries radiation pressure big enough to move micron-scale particles, has also been pressed into service to create localized mixing bowls in microfluidic channels. For example, shaped beams such as Bessel beams - which carry both linear and angular momentum - can be applied directly to create tiny optical vortices that stir around particles in the channel, giving rise to micro-whirlpools that enhance fluid mixing.
Getting smaller and faster
Even these approaches, however, operate at only the scale of optical wavelengths. Ideally, chemists would like to be able to mix fluids locally on chip at even smaller length scales, which would enable experiments at still faster reaction rates.
To get there, the team behind the new research - led by Alexander Shalin of ITMO University, Russia - went to the computer, to model potential mixing schemes that could operate at the nanoscale in a microfluidic channel. Their modeled system draws on the emerging field of all-dielectric nanophotonics. In particular, they focused on the use of so-called Mie resonances to locally enhance and scatter light fields at subwavelength scales around dielectric nanoparticles, in much the same way as plasmonic resonances can boost fields around metallic nanoparticles (see "Meta-Optics with Mie Resonances," OPN, January 2017).
In the scheme modeled by the Russian-Czech team, a silicon cube around 200 nm on each side is planted at the base of the microfluidic channel, which contains both the reagents to be mixed and a population of suspended, chemically inert gold nanoparticles around 40 nm in radius. A circularly polarized green laser beam is then shone down onto the nanocube.
The cube, acting as a dielectric nanoantenna, converts part of the spin angular momentum of the circularly polarized incident light into orbital angular momentum in the scattered light field. The scattered light creates an optical vortex field in the surrounding liquid, the radiation pressure from which nudges the suspended gold nanoparticles along, causing them to swirl within and mix the liquid.
Subwavelength mixing scales
The team’s modeling suggests that the diminutive mixing bowl in this setup would be only a few hundred nanometers in diameter - around half of the illuminating wavelength. That’s an order of magnitude smaller than the length scale achieved when using, for example, a Bessel beam to directly create the same kind of mixing.
The direction of mixing can quickly be reversed by flipping the sense of the circular polarization in the incident light. And, in a bonus, the dielectric cube antenna can also be used as a kind of nanoscale "sorting hat" to separate different-sized gold nanoparticles directly inside the microfluidic chip.
Thus far, these feats have taken place only inside a computer; the team is now looking at ways to realize the proposed concept in physical experiments. Once that’s done, though, the scientists believe that the scheme - which they say can easily be realized using current production processes for microfluidic chips - opens "very exciting perspectives" for microfluidics at very small length and time scales, "such as light-controlled mixing or even on-chip directional fluid navigation."
In addition to researchers at ITMO, the study also included scientists from the Russian Academy of Sciences, the Electrotechnical University and LLC COMSOL, Russia, and the Czech Academy of Sciences, Czechia.

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    Sciences et Avenir / Le 07.05.2020
    Mystérieux événement de la Toungouska : une nouvelle hypothèse pourrait l'expliquer
    Un astéroïde qui a rasé la surface de la Terre a pu provoquer le mystérieux événement de la Toungouska, estiment des chercheurs russes.
    • Par Joël Ignasse
    Ученые выдвинули новую версию падения Тунгусского метеорита. По мнению исследователей Сибирского федерального университета и Красноярского научного центра СО РАН, состоявший из железа астероид диаметром 100-200 метров не долетел до поверхности Земли, а прошел через атмосферу на высоте около 10-15 км, после чего продолжил движение. В атмосфере астероид потерял половину массы в результате нагрева и испарения, что вызвало ударную волну и обширные лесные пожары при полном отсутствии обломков самого астероида.

Le 30 juin 1908, une formidable déflagration au-dessus de la Sibérie Centrale balaya 2000 km² de forêt, abattant des millions d'arbres. La catastrophe ne fit heureusement que très peu de victimes, puisqu'elle se produisit dans une zone quasi-désertique. L'explosion a été enregistrée sur des sismographes : sa magnitude était autour de 5 sur l'échelle de Richter et sa puissance a été estimée à 1000 fois celle de la bombe qui détruisit Hiroshima. Son origine demeure à ce jour encore inexpliquée mais de nouvelles hypothèses émergent toujours.
Un astéroïde de fer
Des dizaines d'explications ont été proposées pour expliquer ce qui est appelé "l'événement de la Toungouska" sans qu'aucune ne soit tout à fait convaincantes. Ce qui laisse la part belle à toutes les théories les plus fantastiques de l'attaque extraterrestre à la percussion d'un mini trou noir. La plupart des hypothèses ont cependant un point commun : elles pointent vers une origine cosmique et font d'un astéroïde ou d'une comète les principaux suspects. C'est d'ailleurs le postulat de l'astéroïde qui est repris par des astronomes de l'Université fédérale de Sibérie et d'autres instituts Russes. Sauf que pour eux, l'objet céleste n'a pas frappé la Terre, il n'a fait que la frôler. Une théorie qui a le grand avantage d'expliquer l'absence de cratère d'impact et de débris mais qui présente aussi des failles.
Pour élaborer leur hypothèse, les Russes ont modélisé les trajectoires et les conséquences du passage d'astéroïdes de 200, 100 et 50 mètres de diamètre dans l'atmosphère terrestre à une altitude comprise entre 10 et 15 kilomètres. Ils ont effectué leurs calculs pour des astéroïdes composés de glace, de roche et de fer. Selon leur étude qui est publiée dans la revue Monthly Notices of the Royal Astronomical Society, c'est un astéroïde composé principalement de fer de 100 à 200 mètres de diamètre qui est responsable de l'événement de la Toungouska. L'astre aurait filé dans l'atmosphère terrestre sur une distance d'environ 3000 km au-dessus de la Sibérie, à une altitude de 11 km et à une vitesse d'au moins 11km/s et serait reparti en direction du Soleil sans heurter la Terre.
Des explications incomplètes
Le scénario imaginé par les chercheurs russes expliquerait plusieurs caractéristiques de l'événement de la Toungouska à commencer donc par l'absence de cratère d'impact. De même sur le site il n'a été retrouvé aucun débris d'un quelconque astéroïde hormis trois petits morceaux de roche dont l'origine n'a pas été confirmée. Ce manque de débris s'expliquerait par la grande vitesse de l'astéroïde et sa composition ferreuse : il était trop chaud et il perdait sa masse par sublimation de ses atomes de fer. En d'autre termes, son enveloppe s'est évaporée sans laisser de traces visibles et il a été assez solide pour résister à son passage atmosphérique sans se désagréger puis il a continué sa route vers le Soleil. Ce modèle explique en outre le phénomène lumineux qui a baigné l'Europe dans les jours qui ont suivi l'événement. De très nombreuses observations font état d'une luminosité importante la nuit causée par des nuages noctulescents et de couleurs dans le ciel tout à fait singulières rappelant d'autres catastrophes passées comme l'éruption gigantesque du Krakatoa en 1883. Ces phénomènes auraient été causés par une forte présence de poussières en provenance de l'astéroïde dans les hautes couches atmosphériques.
Toutefois les auteurs notent eux-mêmes que leur théorie fait abstraction de la conséquence la plus évidente de l'événement de la Toungouska : les millions d'arbres qui ont été visiblement aplatis par une énorme onde de choc. Cette onde à très bien pu se produire dans les circonstances décrites dans leur étude mais ils n'ont ni modélisé ni étudié les différents types d'astéroïdes qui auraient pu l'engendrer. D'autre part ce scénario d'un astéroïde rasant la Terre à seulement 11 kilomètres d'altitude est fortement improbable même si il n'est pas impossible. Il faudrait une conjonction tout à fait exceptionnelle pour qu'un astéroïde puisse ainsi frôler la Terre et poursuivre sa route vers le Soleil.

© Sciences et Avenir.
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    Астрофизики из Физического института им. П.Н.Лебедева РАН, Московского физико-технического института и Института ядерных исследований РАН выяснили, откуда берутся нейтрино высоких энергий. Оказалось, что эти мельчайшие элементарные частицы рождаются вблизи массивных черных дыр в активных ядрах галактик. Во время падения вещества в черную дыру часть потока частиц выбрасывается обратно, ускоряется - и возникают нейтрино.

Russian astrophysicists have come close to solving the mystery of where high-energy neutrinos come from in space. The team compared the data on the elusive particles gathered by the Antarctic neutrino observatory IceCube and on long electromagnetic waves measured by radio telescopes. Cosmic neutrinos turned out to be linked to flares at the centers of distant active galaxies, which are believed to host supermassive black holes. As matter falls toward the black hole, some of it is accelerated and ejected into space, giving rise to neutrinos that then coast along through the universe at nearly the speed of light.
The study came out in the Astrophysical Journal and is also available from the arXiv preprint repository.
Neutrinos are mysterious particles so tiny that researchers do not even know their mass. They pass effortlessly through objects, people, and even entire planets. High-energy neutrinos are created when protons accelerate to nearly the speed of light.
The Russian astrophysicists focused on the origins of ultra-high-energy neutrinos, at 200 trillion electron volts or more. The team compared the measurements of the IceCube facility, buried in the Antarctic ice, with a large number of radio observations. The elusive particles were found to emerge during radio frequency flares at the centers of quasars.
Quasars are sources of radiation at the centers of some galaxies. They are comprised by a massive black hole that consumes matter floating in a disk around it and spews out extremely powerful jets of ultrahot gas.
"Our findings indicate that high-energy neutrinos are born in active galactic nuclei, particularly during radio flares. Since both the neutrinos and the radio waves travel at the speed of light, they reach the Earth simultaneously," said the study's first author Alexander Plavin.
Plavin is a PhD student at Lebedev Physical Institute of the Russian Academy of Sciences (RAS) and the Moscow Institute of Physics and Technology. As such, he is one of the few young researchers to obtain results of that caliber at the outset of their scientific career.
Neutrinos come from where no one had expected
After analyzing around 50 neutrino events detected by IceCube, the team showed that these particles come from bright quasars seen by a network of radio telescopes around the planet. The network uses the most precise method of observing distant objects in the radio band: very long baseline interferometry. This method enables "assembling" a giant telescope by placing many antennas across the globe. Among the largest elements of this network is the 100-meter telescope of the Max Planck Society in Effelsberg.
Additionally, the team hypothesized that the neutrinos emerged during radio flares. To test this idea, the physicists studied the data of the Russian RATAN-600 radio telescope in the North Caucasus. The hypothesis proved highly plausible despite the common assumption that high-energy neutrinos are supposed to originate together with gamma rays.
"Previous research on high-energy neutrino origins had sought their source right 'under the spotlight.' We thought we would test an unconventional idea, with little hope of success. But we got lucky!" Yuri Kovalev from Lebedev Institute, MIPT, and the Max Planck Institute for Radio Astronomy commented. "The data from years of observations on international radio telescope arrays enabled that very exciting finding, and the radio band turned out to be crucial in pinning down neutrino origins."
"At first the results seemed 'too good' to be true, but after carefully reanalyzing the data, we confirmed that the neutrino events were clearly associated with the signals picked up by radio telescopes," Sergey Troitsky from the Institute for Nuclear Research of RAS added. "We checked that association based on the data of yearslong observations of the RATAN telescope of the RAS Special Astrophysical Observatory, and the probability of the results being random is only 0.2%. This is quite a success for neutrino astrophysics, and our discovery now calls for theoretical explanations."
The team intends to recheck the findings and figure out the mechanism behind the neutrino origins in quasars using the data from Baikal-GVD, an underwater neutrino detector in Lake Baikal, which is in the final stages of construction and already partly operational. The so-called Cherenkov detectors, used to spot neutrinos - including IceCube and Baikal-GVD - rely on a large mass of water or ice as a means of both maximizing the number of neutrino events and preventing the sensors from accidental firing. Of course, continued observations of distant galaxies with radio telescopes are equally crucial to this task.

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    В Красноярском крае издана уникальная «Красная книга» Эвенкии, в которой представлены 45 редких и малочисленных животных, обитающих в этом регионе. Сбор и анализ данных провели специалисты Центра мониторинга биоразнообразия Сибирского федерального университета, а сама книга издана в рамках грантовой программы «Восточно-Сибирской нефтегазовой компании».

The unique Red Book of Evenkia was published as part of the grant programme of the East Siberian Oil and Gas Company, a part of the Rosneft oil production complex. It presents 45 rare and small animals living in this region.
Rosneft pays great attention to environmental protection during its production activities. A list of species that are indicative of the sustainable state of Arctic ecosystems was compiled, and a set of data on the appearance of various animal species in Rosneft's licence areas was analysed under large-scale Biodiversity Conservation Programme. Particular attention was paid to rare and protected species, including those listed in the Red Book of the Russian Federation, regional Red Books, and the Red List of the International Union for Conservation of Nature.
Specialists of the Biodiversity Monitoring Centre of the Siberian Federal University helped to collect and structure the information obtained in the course of many years of research, as well as to conduct a comprehensive analysis of the Evenkia ecosystem. This resulted in obtaining unique data on the wildlife of Evenkia, which formed the basis of the publication.
The textbook contains brief information on rare, small and endangered species, their appearance, habitats and numbers. It is intended for environmentalists, ecologists and biologists as well as for teachers, schoolchildren and students.
The unique natural complex of Evenkia is the subject of research by many Russian and foreign environmental scientists.
World Wildlife Fund experts have included the area in the list of especially valuable natural areas due to the presence of places not affected by human activities. The biological resources of the area are diverse and rich, as 240 bird species, 43 mammals and 25 fish species live here. Most of them belong to particularly valuable species.
With one in five species on the planet on the verge of extinction, keeping the Red Book is an important part of environmental protection measures, including the fragile ecosystems of northern territories.
Siberian scientists are sure that only joint efforts of the authorities, business, and local population aimed at preservation of the unique ecosystem will enable us to pass on to future generations the natural heritage of severe lands of Siberia.
Note for Editors:
The East Siberian Oil and Gas Company, a subsidiary of Rosneft Oil Company, develops the Yurubcheno-Tokhomskoye oil and condensate field in the Evenki district of Krasnoyarsk Territory.
Supporting the culture and traditional way of life of the indigenous people of Evenkia is one of the key lines of the social work of the company. During the years of the work in the region, Vostsibneftegaz has implemented a lot of social, charitable and grant programmes.
The Vostsibneftegaz grant scheme has been in operation for six years. Within the period, the company has supported 18 scientific projects such as the Siberian Federal University's project to study the population of wild reindeer and lesser white-fronted goose listed in Red Book; Central Siberian reserve on the research of a population of the Siberian sable, research institute of the ecology of fishery reservoirs on working out of biotechnics of artificial reproduction of the Siberian taimen. The Sukachev Institute of Forest of the Siberian Branch of Russian Academy of Sciences conducted studies of microbiological characteristics of soils of post-fire successions in forest cryogenic ecosystems in Middle Siberia, the Trade and Economics Institute of the Siberian Federal University developed scientific and practical justification for the production of bread for the northerners from Jerusalem artichoke, a perennial herbaceous tuber plant.
The implementation of the grant schemes helps save the unique natural environment, national culture, and traditional way of life and cultural authenticity of indigenous population of Evenkia.

Copyright © 2020 Surperformance. All rights reserved.
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    Российские и итальянские ученые разработали «электронный нос» - компактную сенсорную систему на основе углеродных модифицированных нанотрубок, которая может анализировать выдыхаемый воздух и выявлять патологии дыхательных путей и органов.

Researchers from Russia and Italy have proposed a compact sensor system that can implement the functionality of an electronic nose device and have developed a reproducible technology for its manufacture. The device is a flexible electronics platform that can analyze exhaled air as well as identify pathologies of the respiratory tract and organs.
During the experiments, the device demonstrated high accuracy in determining patients with chronic obstructive pulmonary disease (COPD), an inflammatory disease of the respiratory tract, which increases the risk of complications when during COVID-19 infection.
Chronic obstructive pulmonary disease (COPD) develops in the bronchial mucosa in response to pathogenic external factors and leads to a negative change in the functions of the respiratory tract. A person with COPD cannot receive the necessary oxygen because inhaled air flow is limited. COPD is commonly caused by gases and volatile particles such as dust, tobacco, cadmium and silicon particles, and others. The methods for detecting this disease are complex and time consuming, which is inextricably linked to a threat to the patient's health.
Conventional methods for breath analysis, such as gas chromatography and mass spectroscopy, are expensive and time-consuming, so new approaches are required that are notable for their low cost and speed of testing. COPD is an urgent problem, as the disease may lead to the limitation of physical performance and disability of patients. It is important to note that people with COPD are most at risk for complications if they become infected with COVID-19.
"Malfunctioning of human organs causes a change in a number of processes in the metabolism, which affects the composition of exhaled air. Its analysis can be used to identify diseases of the respiratory system as well as other internal organs, such as the stomach," explains Dr. Ivan Bobrinetskiy, project manager for the Russian Science Foundation grant, leading research associate of the National Research University of Electronic Technology. "The proposed concept of the electronic nose allows for operational monitoring and preliminary detection of diseases in just a few minutes. At the same time, the sensors are reusable, and the basic data and the identification of possible pathologies of organs are transferred from the device to digital mode using methods of statistical data analysis, including the capabilities of artificial intelligence. "
The system is based on modified carbon nanotubes (CNTs), which allows the electronic nose to combine multiple properties. For example, flexible conductive films can be made from carbon nanotubes. Such films are needed in order to provide the system with an electronic structure layer responsible for the operation of the device. "CNTs were synthesized by aerosol chemical vapor deposition and deposited in the form of thin transparent and conductive films. This technology is highly reproducible, easily scalable and allows applying films of nanotubes to any surface," said Albert Nasibulin, professor at the Skolkovo Institute of Science and Technology and the Russian Academy of Sciences.
The study of the effectiveness of the new system involved 12 patients with COPD and nine healthy individuals in accordance with the rules of clinical trials. Breath sampling was carried out in disposable polytetrafluoroethylene (PTFE) plastic bags made of a very inert material and containing a sensor matrix. The subjects inhaled and inflated the bag as much as possible through a plastic straw. When the straw was removed, the packages were sealed. The sensor matrix inside the bag was in contact with exhaled air for about three minutes, so that all sensors could fully work and interact with the gas molecules that characterize the pathology. Then the system was cleaned with dry air for the next study. Samples were collected from each participant with an interval of one hour.
Since the system detected all people with COPD, it can be argued that the device is effective. In the exhaled air, an increased concentration of nitrogen dioxide was detected. It should be noted that the gas content is less than one molecule per million molecules of the exhaled air, which indicates high sensitivity of the developed sensors.
The researchers have also successfully tested their system on gases that can characterize other diseases. The volatiles selected for this study (ammonia, nitrogen dioxide, sodium hypochlorite, water, benzene, hydrogen sulfide, acetone, ethanol and 2-propanol) are associated with specific diseases and can potentially be considered as their biomarkers. Thus, the content of 2-propanol, benzene, ethanol and acetone in exhaled air is increased in people with lung cancer, while acetone is found in patients with diabetes. A high concentration of ammonia in human breath is associated with liver or kidney diseases, and hydrogen sulfide has been proposed as a biomarker of asthma. The concentration of sodium hypochlorite is an increased content in exhaled air in children with bronchial asthma and cystic fibrosis.

© Medical Xpress 2011-2020 powered by Science X Network.
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    Российские ученые разработали схему шифрования и хранения данных «умных» устройств, входящих в инфраструктуру Интернета вещей (IoT), с целью защиты от взлома и перехвата информации.

The Internet of things is a new technology that is being studied at South Ural State University. The popularity of the concept where several devices are interconnected and can be controlled remotely is explained by its convenience in use. One of the main tasks for professionals working with the Internet of things is to protect data transmitted through the Network. The transmission, encryption, and storage of information that surpasses existing analogs in reliability was proposed by a team of Russian scientists, including scientists of South Ural State University. The article on the development of a new architecture was published in one of the most highly-ranked computer science journals, the IEEE Internet of Things Journal.
Smart devices need data protection
Smart homes, cars, and cities have long ceased to be a part of the future, but an indicator of the present. Technologies allow us to make human life more comfortable by ensuring the interaction of several devices of the computer network, sensors, and mechanisms. The concept of such a smart space is called the Internet of Things (IoT). Experts say the number of IoT devices can exceed the number of mobile phones in the world; the usability of this technology will be appreciated.
However, the connection between devices leads to higher risks of information loss. Since they are all transferred from one subject to another through the Web, the information can be stolen. For example, a smart meter can transmit information about when lights in a house are turned on and off. After analyzing it, it is easy to calculate the time when the owners are absent and enter the apartment. Threats can be larger and more serious, so specialists are working on designing a reliable IoT architecture. It should prevent information loss, a system crash, prevent a data breach that is difficult to predict in advance. An international team of scientists including the director of School of Electronics and Computer Science (HSE) of South Ural State University Gleb Radchenko and the head of the International Laboratory for Problem-Oriented Cloud Environments, HSE, Andrei Chernykh, as well as their colleagues from Russian Academy Sciences, Moscow Institute of Physics and Technology, Tsinghua University (China) and the Center for Scientific Research and Higher Education in Ensenada (Mexico), proposed their own version of encryption and storage of data on IoT devices.
Scientists have introduced a storage architecture called WA-MRC-RRNS. Instead of one cloud storage, experts suggest using several. They may belong to different owners, and the proposed encryption method allows you to divide the information into independent parts that are downloaded to different clouds.
"Of course, when we observe the large-scale implementation of the Internet of things system in all areas of life, the threats can be widespread. Information loss, access denial, information leakage, collusion, technical failures, and data security breaches are difficult to predict and anticipate in advance. Instead of collecting all the data in one cloud, we proposed a different encryption scheme. It will allow you to place parts of the data in different cloud storage owned by different owners. Even if some of the data is intercepted, an attacker will not be able to recover information from a partial data set. If part of the data is completely lost as a result of the failure, such a scheme will allow recovering data from those parts that were sent to other storages," Gleb Radchenko said.
The scheme will be improved
To prove the effectiveness of the proposed data encryption method, an international team of researchers conducted a theoretical analysis of information loss, data redundancy, coding, and decoding speed. It turned out that when using the WA-MRC-RRNS storage architecture, the probability of data loss is less than in existing schemes, and the data transfer rate is higher.
In further studies, scientists intend to test the performance of the proposed scheme in idle conditions, malfunctions, as well as changes in parameters. WA-MRC-RRNS is waiting for a comparison with the already known methods of replication, erasure codes, secret sharing schemes, and error correction codes encryption.
The Internet of things has been studied for several years at South Ural State University. In 2018, an agreement was signed with Samsung, the world leader in the field of information technology and radio electronics, to open the Samsung IoT Academy and a unique training laboratory for studying the Internet of Things technologies at the Higher School of Electronics and Computer Science.
Significant results have been achieved in the creation of IT at South Ural State University. Research is developing with supercomputer modeling in the field of artificial intelligence, Big Data processing, storage, and mining.
Research in the digital industry is one of three strategic areas for the development of scientific and educational activities of South Ural State University along with ecology and materials science. SUSU is a participant in the 5-100 Project, designed to increase the competitiveness of Russian universities among the world's leading research and educational centers.

© Science X 2004-2020.
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    EurekAlert / 19 May 2020
    Physicist from St Petersburg University becomes the first Russian scientist to receive the ISCS 2020
    This award is given for innovative contributions in the field of complex semiconductor devices and devices with quantum nanostructures.
    Физик СПбГУ Алексей Кавокин стал первым российским лауреатом премии ISCS Quantum Devices, которая вручается за достижения в области сложных полупроводниковых приборов и устройств с квантовыми наноструктурами. Премия 2020 года присуждена ученому за предсказание бозе-эйнштейновской конденсации экситонов и экситонных поляритонов при комнатной температуре, что позволило создать поляритонные лазеры. Они потребляют в несколько раз меньше энергии, чем традиционные полупроводниковые лазеры, кроме того, на их основе можно создавать базовые элементы квантовых компьютеров - кубиты.

The Organising Committee has pointed out that the prize was awarded to Alexey Kavokin for predicting Bose-Einstein exciton and excitonic polaron condensation at room temperature. This has led to the creation of polariton lasers. Polariton lasers consume several times less energy than a conventional semiconductor laser. Most importantly, they can be used to create qubits, basic elements of quantum computers of the future. These technologies make a significant contribution to quantum computing systems.
'Russia is one of the world leaders in polaritonics, a field of physics studying light and material quasi-particles, or liquid light. On the basis of liquid light, we are developing polariton lasers - devices that can bring our country a victory in the race of quantum technologies. While the American giants Google and IBM are investing billions in quantum technologies based on superconductors, we are pursuing a much cheaper and potentially more promising path by developing a polariton platform for quantum computing. For me, this award is evidence that our efforts in the field of quantum polaritonics have been recognised by the international scientific community,' said Alexey Kavokin.
The Quantum Devices Award was founded in 2000 by Fujitsu Quantum Devices Ltd., affiliated with Fujitsu, a major Japanese electronics manufacturer and IT company. Today, the award is funded by the Japanese section of the steering committee of the International Symposium on Compound Semiconductors (ISCS) along with two other prestigious scientific awards - The Welker Award and The Young Scientist Award. It should be noted that the Quantum Devices Award was previously conferred on scientists from Germany, Japan, Switzerland, the UK and many other countries, but it is the first time that the award has been received by a scientist from Russia.
Alexey Kavokin heads the Spin Optics Laboratory of St Petersburg University and the Quantum Polaritonics group at the Russian Quantum Centre. He is also a Professor at the University of Southampton (UK), where he heads the Department of Nanophysics and Photonics. In 2011, he won a mega-grant from the Government of the Russian Federation, as part of which the I.N. Uraltsev Spin Optics Laboratory was established. In 2018, the Professor headed the International Centre for Polaritonics at the Westlake University in China.
Because of the global pandemic the awards ceremony will take place next year - during Compound Semiconductor Week 2021 in Sweden.

Copyright © 2020 by the American Association for the Advancement of Science (AAAS).
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    Используя фемтосекундный лазер, ученые из Университета ИТМО продемонстрировали первый химически синтезированный оптический переключатель на основе металлоорганической структуры. Такие устройства позволяют передавать информацию с помощью света, что в будущем будет полезно для создания сверхбыстрых оптических элементов памяти.

Optical switches allow for transmitting information using light, which will be useful for the development of ultrafast optical memory cells in the future. Using a femtosecond laser usually used in chemistry for gas absorption, ITMO University scientists have demonstrated how to create an all-optical switch based on a metal-organic framework that can be synthesized in vitro. The research has been published in the journal Angewandte Chemie.
Current devices transmit information based on the movement of electrons. It is expected that computing elements operating on photons will work faster, more efficiently, and consume less energy. But in order to realize optical computing, it is necessary to solve a number of theoretical and engineering problems. One of them is achieving reliable, energy-efficient and low-cost light control.
"All of today's digital electronics are built on so-called triggers," explains Nikita Kulachenkov, a junior research associate at ITMO University and one of the paper's authors. "These are devices for switching between two states, zero and one. For optical devices which might in the future take the place of our electronic devices, we also need a special switch."
One of the options for such a switch comes in the form of metal-organic frameworks (MOFs). This is a class of functional materials that combine the properties of crystal lattice substances and organic compounds. But for the purposes of developing optical computing devices, the most important aspect is that some MOFs contain special photochromic compounds capable of changing their optical properties when exposed to light. This process, however, usually takes place over a relatively long period of time, from several minutes to several days, which puts significant limitations on the practical application of such structures as switchers.
A group of scientists from ITMO University's Russian-French laboratory, headed by Valentin Milichko, took a different path - the researchers used standard metal-organic frameworks that don't contain any photochromic compounds and have been used in the chemical industry for a long time. "We decided to use a group of MOFs that demonstrate the property of changing their structure under external stimuli such as pressure, temperature and others," says Nikita Kulachenkov. "Among these metal-organic frameworks was HKUST-1. It was very well-researched in the field of gas absorption, but no one could ever have thought that its properties, and consequently, its structure, could undergo significant changes when exposed to light."
Experiments with HKUST-1 metal-organic frameworks have shown that when subjected to an ultra-short pulse of an infrared laser, this MOF suddenly starts to transmit less light. "The number of photons passing through the MOF decreased by about 100 times," explains Nikita Kulachenkov. "The switch-over period amounted to several dozen milliseconds. This is two to three orders better than offered by existing MOF-based organic systems."
The researchers found that the femtosecond impact generated by the infrared laser is, in effect, enough to evaporate the water from the metal-organic framework. The MOF becomes less transparent for the laser-emitted light. But once the light is off, the framework reabsorbs water molecules from the air and returns to its initial state.

© Phys.org 2003-2020 powered by Science X Network.
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    До недавнего времени некрупные ихтиозавры Nannopterygius, жившие в юрском периоде, считались редким и малоизученным видом. Единственный скелет был найден и описан в Великобритании в 1871 году и с тех пор хранится в Музее естественной истории в Лондоне в застекленной витрине на высоте 5 метров, то есть практические недоступен для изучения. Сотрудник Палеонтологического института им. А.А.Борисяка РАН Николай Зверьков решил эту проблему с помощью фотокамеры, штатива и обычной удочки. В результате выяснилось, что ихтиозавр не такой уж редкий - к роду нанноптеригиев относится ряд давно известных форм, в том числе на территории России, которых раньше причисляли к офтальмозаврам.

A Russian paleontologist visiting the Natural History Museum in London desperately wanted a good look at the skeleton of an extinct aquatic reptile, but its glass case was too far up the wall. So he attached his digital camera to a fishing rod and - with several clicks - snagged a big one, scientifically speaking.
Images from the "selfie stick" revealed that the creature, whose bones were unearthed more than a century ago on a coast in southern England, seemed very similar to a genus of ichthyosaurs he recognized from Russian collections.
He emailed the photos of the dolphin-like ichthyosaur to fellow paleontologist Megan L. Jacobs, a Baylor University doctoral candidate in geosciences. She quickly realized that the animal's skeletal structure matched not only some ichthyosaurs she was studying in a fossil museum on the English Channel coast, but also some elsewhere in the United Kingdom.
Jacobs and paleontologist Nikolay G. Zverkov of the Russian Academy of Sciences - who "fished" for the ichthyosaur - merged their research, studying their collective photos and other materials and ultimately determining that the Russian and English ichthyosaurs were of the same genus and far more common and widespread than scientists believed.
Their study is published in the Zoological Journal of the Linnean Society.
"Ichthyosaurs swam the seas of our planet for about 76 million years," Jacobs said. "But this 5-foot ichthyosaur from some 150 million years ago was the least known and believed to be among the rarest ichthyosaurs. The skeleton in the case, thought to be the only example of the genus, has been on display in the Natural History Museum in London since 1922.
"Nikolay's excellent detailed photos significantly expand knowledge of Nannopterygius enthekiodon," she said. "Now, after finding examples from museum collections across the United Kingdom, Russia and the Arctic - as well as several other Nannopterygius species - we can say Nannopterygius is one of the most widespread genera of ichthyosaurs in the Northern Hemisphere."
Additionally, the study described a new species, Nannopterygius borealis, dating from about 145 million years ago in a Russian archipelago in the Arctic. The new species is the northernmost and youngest representative of its kind, Jacobs said.
Previously, for the Middle and Late Jurassic epochs, the only abundant and most commonly found ichthyosaur was Ophthalmosaurus, which had huge eyes and was about 20 feet long. It was known from hundreds of specimens, including well-preserved skeletons from the Middle Jurassic Oxford Clay Formation of England, Jacobs said.
"For decades, the scientific community thought that Nannopterygius was the rarest and most poorly known ichthyosaur of England," Zverkov said. "Finally, we can say that we know nearly every skeletal detail of these small ichthyosaurs and that these animals were widespread. The answer was very close; what was needed was just a fishing rod."

Copyright 2020 ScienceDaily.
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    В 1970-х годах при раскопках в районе озера Байкал советские археологи обнаружили осколок человеческого зуба. Несколько десятилетий спустя экспертам Института истории человека Макса Планка удалось выделить ДНК из зубной мякоти. Обладатель зуба, живший около 14 тысяч лет назад, оказался самым древним близким родственником коренных американцев за пределами американского континента. Статья по результатам исследования с участием российских ученых (ИАиЭт СО РАН, НИИ и Музей антропологии МГУ) опубликована в журнале Cell.

A new study has revealed the oldest link yet between Native Americans and their ancestors in East Asia: a 14,000-year-old tooth belonging to a close cousin of today’s Native Americans, found thousands of kilometers from the landmass that once connected Eurasia and the Americas.
"It’s very cool," says Jennifer Raff, a geneticist at the University of Kansas, Lawrence, who studies the peopling of the Americas. The work suggests the Siberian ancestors of North America’s Indigenous peoples were more widespread and mobile than previously believed, she says. It may also indirectly support the hypothesis that Native Americans’ ancestors became isolated from their Asian forebears on Beringia, an ancient land bridge that connected Siberia to Alaska.
Sometime about 20,000 years ago, people began to cross the eastern tip of Siberia onto Beringia. Exactly where they lived and roamed in Siberia before that, however, has long been a mystery.
The new study provides the oldest evidence yet of a close genetic ancestor to Native Americans in Eurasia. It’s also much farther from Beringia that many would have suspected, says the study’s senior author, Johannes Krause, an archaeogeneticist and director of the Max Planck Institute (MPI) for the Science of Human History. In the 1970s, Russian archaeologists excavated a site called Ust-Kyakhta sandwiched between the southern banks of Lake Baikal and the Mongolian border in south-central Russia. They recovered thousands of stone and bone tools, ceramics, and reindeer and fish bones - plus a sliver of a human tooth.
The tooth sat in a collections drawer for decades, until Svetlana Shnaider, an archaeologist at the Russian Academy of Sciences, brought it to the attention of ancient DNA experts at MPI. "Initially I was quite skeptical" that it could still contain DNA, Krause says.
But Siberia’s cold, dry environment favors DNA preservation, and the team succeeded in sequencing the tooth bearer’s genome from dental pulp. Based on radiocarbon dates of charcoal and bones found alongside the tooth, researchers calculated it to be about 14,000 years old. The genome showed the individual was a man - one who shared the same distinctive mixture of East Asian and Eurasian ancestry as today’s Native Americans. That makes him the oldest known close relative of Native Americans outside the Americas, the researchers report today in Cell.
The man lived 4500 kilometers from Beringia and nearly 3200 kilometers from a woman in northeastern Siberia who shared about two-thirds of her genome with living Native Americans. This suggests the source population from which Native Americans emerged occupied a vast region of northeastern Eurasia, Krause says.
That impressive range, in turn, implies that the group directly ancestral to Native Americans became genetically isolated in Beringia, not in Siberia, where they had been moving around for thousands of years, Raff says. Today, the people near Lake Baikal have virtually none of the genetic hallmarks of that older population, indicating it was replaced by migrants of primarily northeast Asian ancestry about 10,000 years ago.
People around Lake Baikal continued to move around and interact with other groups for thousands of years, according to additional findings in the paper. Two of them, buried side by side about 4200 years ago, bore the DNA signature of the plague-causing bacteria Yersinia pestis, which until now had only been found much farther west, in people with a genetic connection to the Eurasian steppe.
"That [the bacterium] moved all the way from the Baltic to the Baikal over more or less 100 years is a bit of a surprise," Krause says. "Today, we see something like coronavirus that went everywhere within 3 months, but the Bronze Age was not such a globalized world."
The combination of both human and pathogen ancient DNA offers a rare historical window into a place critical to understanding Native American, Asian, and European genetics, says Priya Moorjani, a geneticist at the University of California, Berkeley. "Every sample thus far from this region has helped to refine our understanding of human history and evolution."

© 2020 American Association for the Advancement of Science. All rights Reserved.
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    Сотрудники Первого Московского государственного медицинского университета им. И.М.Сеченова совместно с коллегами из других российских институтов сравнили РНК трех существующих подтипов вируса клещевого энцефалита, обнаруженных в разных странах, и определили возраст каждого из них, а также пути распространения. Оказалось, что сибирскому и дальневосточному подтипам - 700 и 900 лет соответственно, а европейскому - около 1600.

Researchers from Sechenov University together with colleagues from several Russian institutes analyzed data on the RNA structure of tick-borne encephalitis virus. Much larger than in previous studies, the data volume of the new study allowed them to estimate the age of the virus subtypes and track its spread in Eurasia. The results of the study were published in the journal Viruses.
Tick-borne encephalitis is common in Central and Eastern Europe and a wide band in southern Siberia and the Far East. This disease is dangerous due to the ability of the virus to penetrate the brain and spinal cord, causing motor disorders, cognitive impairments and, in severe cases, paralysis and death. Every year in Russia, 1,500-2,000 people are infected, with about 30% developing neurological complications and 20-100 people dying. The pathogen belongs to the genus Flavivirus (it also includes Zika virus and the virus that causes dengue fever) and is transmitted mainly through tick bites. There are three subtypes of the virus: Far Eastern, Siberian and European. Each of them is predominant in the region after which it is named, although this division is quite coarse - for example, cases of infection with the Siberian subtype were observed in the Baltic States and Sakhalin, and with the European one - in South Korea and the Altai Mountains.
In recent years, the spread of the virus has expanded to northern areas (Kola Peninsula, Arkhangelsk Region) and mountainous regions (in Central Europe and Italy). In 2019, the first cases of infection were recorded in the UK and the Netherlands. To respond promptly to the emergence of the virus in new territories, it is necessary to understand what affects its spread and evolution. Existing studies provide different, sometimes contradictory results, but new data collected in recent years can clarify the situation.
The authors of the article used GenBank - a database that stores more than 200 million nucleotide sequences of RNA and DNA of various species. The data are supplied by scientists from different countries, and their volume is constantly growing, in common with the number of sequences describing the RNA of the tick-borne encephalitis virus - in ten years the number has increased fivefold. Using computer algorithms, researchers compared the RNA of viruses found in different years on the territory of several countries. Knowing the 'distance' (the proportion of divergent nucleotides) between samples and the date of their receipt, one can estimate the time of divergence of species or the division of a species into subtypes.
This method is based on the assumption that the sequence of nucleotides in a single species changes at an approximately constant rate, and is called the molecular clock. Using this method, scientists estimated the age of the most recent common ancestor for each of the subtypes.
The result (about 700 and 900 years for the Siberian and Far Eastern subtypes, respectively) is consistent with earlier studies, while the age of the European subtype (about 1,600 years) was estimated for the first time after the virus was spotted in the Netherlands. The researchers also tried to find out how genetically similar viruses of the same subtype ended up in different countries at a distance of thousands of kilometres from each other. There are several possible explanations. First, viruses (or ticks infected with them) can travel long distances with animals, such as migratory birds or bats. Second, human activity can contribute to the spread of the virus: transportation of livestock or introduction of animals suitable for hunting in new territories.
"The most important result of the work was that most of the virus spreading events occurred in the last three or four centuries, and in many cases we have observed the transfer of the virus for thousands of kilometres in the last 50-100 years, and viruses in Europe have completely mixed over the last 100-200 years." - Alexander Lukashev, Study Co-Author and Director of the Institute of Medical Parasitology and Tropical Medicine, Sechenov University. "This allows us to consider tick-borne encephalitis as a highly dynamic disease, even as an emerging disease in many regions, and to think about an anthropogenic factor (the spread of infected ticks as a result of transportation of domestic and wild animals) as one of the main mechanisms behind the expansion of the virus."
In addition, scientists have proposed an algorithm that simulates the compilation of samples as used in earlier studies. With its help, the authors of the article showed that the differences in results of previously published studies are well explained by the selection of the sequences included in the study.

News-Medical.net - An AZoNetwork Site, © 2000-2020.
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    Washington Post / May 22, 2020
    Parts of Siberia are hotter than Washington, with temperatures nearly 40 degrees above average
    Snow cover is disappearing, sea ice is melting and fires, including possible ‘zombie’ blazes, are raging.
    • By Andrew Freedman and Matthew Cappucci
    Температурные отклонения от среднего уровня в Сибири в этом году являются одними из самых высоких в мире - в апреле и мае здесь наблюдалось экстремальное потепление до 16 градусов выше нормы, не считая необычно теплой зимы. Сибирское тепло уже оказывает влияние на арктические экосистемы: например, лед в Карском море начал таять более чем на месяц раньше обычного.

Siberia is in the throes of a heat wave that would be considered warm even by the standards of those living outside the Arctic Circle.
In Washington, for example, the temperature has been stuck in the 60s all week, reaching a maximum of 73 degrees Thursday. Yet several stations in North Central Siberia, including areas near or above the Arctic Circle, are seeing temperatures climb well into the 80s. On Friday, the town of Khatanga, Siberia, located well north of the Arctic Circle, recorded a temperature of 78 degrees, some 46 degrees above normal. The typical maximum temperature for the day at that location is 32 degrees. The town obliterated its previous record high for the date of 54 by some 24 degrees and its monthly record of 68 by about 10 degrees.
The Siberian warmth in May is not a fluke event, either; instead, it’s been a consistent feature since the winter. Temperature departures from average in Europe and Asia have helped push global average surface temperatures to record highs this year, and on global temperature maps, these regions stand out as splotches of crimson red. The warmth in Siberia is already having repercussions on Arctic ecosystems, with unusually large Siberian wildfires already burning this year, snow cover plummeting unusually quickly and sea ice cover in areas such as the Kara Sea, which lies to the north of Central Siberia, at a record low for the date, having begun its seasonal melt more than a month earlier than is typical. In recent years, scientists have raised growing concerns about the stability of Arctic permafrost, including stretches of permanently frozen soil located throughout Siberia. When the permafrost thaws, carbon dioxide and other planet-warming greenhouse gases that had been locked away for centuries is freed up, constituting an accelerant to global warming. Scientists refer to this phenomena as the somewhat innocuous-sounding "positive climate feedback," which in reality is not a good thing.
According to Zack Labe, a graduate student at the University of California at Irvine who researches Arctic climate change, what has recently been taking place in Siberia has been extraordinary.
"Although Siberia is known for wild temperature swings, the persistence and magnitude of warmth over the region so far this year has been astonishing," he said via email. "This week is an example of an extreme event, with summer-like temperatures over parts of Western Siberia thanks to a strong upper level ridge. We can already see this reflected in snow cover data, as there are large negative departures of snow extent stretching across the entire Siberian coast of the Arctic," he said. Labe noted that ice in the Kara Sea has reached a record low for the date, and ice cover is thinner than average along the entire coastline of northern Siberia. He said the warmth is likely conditioning the ice to melt further by melting snow cover lying on top of the sea ice. This turns highly reflective ice cover into snow and ice that has a lower reflectivity, known as its albedo, which means that it absorbs more incoming solar radiation.
"This may make the sea ice more vulnerable to melting later in the summer, if weather conditions permit," Labe said. "Overall, the weather patterns in June through August will dictate the extent of melting closer to the September minimum."
This year, Siberian fires have gotten off to a fast, and unusually expansive, start. Russian officials have stated they expect the summer will potentially be the hottest the region has seen, with an unusually destructive fire season. Fires in the vast forests of Siberia burned 7 million acres last year, an area larger than the state of Maryland, and sent smoke drifting around the world. This year, 1.5 million acres have burned. Mark Parrington, a senior scientist at the European Center for Medium-Range Weather Forecasts (ECMWF) in Reading, England, said via email that fire-related emissions around the Arctic Circle and Siberia’s Sakha Republic have not exceeded average data from 2003 through 2019. However, Labe said there have been trends of fires showing up shortly after snow cover melts, which is a topic of discussion in the fire science community. Some scientists are noting how quickly the hot spots are showing up on satellite imagery and questioning whether these are actually "zombie fires" from last summer that survived the winter by burning in layers of vegetation under the snow.
The temperature departures from average in Siberia this year are some of the highest of any area on Earth. Since January, the region has been running at least 5.4 degrees (3 Celsius) above the long-term average, according to a recent report from the National Oceanic and Atmospheric Administration. According to Robert Rohde of Berkeley Earth, which monitors global temperature trends, Russia averaged a temperature anomaly of nearly 11 degrees (6 Celsius) above average for the January to April time period.
"That’s not only a new record anomaly for Russia," Rohde wrote via Twitter. "That’s the largest January to April anomaly ever seen in any country’s national average."
The polar vortex is helping lead to record warmth
Several factors conspired to produce such a mild winter in Siberia, and are still working to bring freak warmth now. Among them? The polar vortex spent much of the winter near or at record strength. When the polar vortex is strong, it forms a frigid upper-air doughnut of winds that doesn’t permit much Arctic chill to slip south to the mid-latitudes. When that happens, areas along the vortex’s periphery that would usually experience frigid weather remain just outside its frosty sphere of influence. In recent weeks, the vortex has undergone its annual spring collapse, making it easier for intense ridges of warm high pressure to build in. Most recently, a prominent bubble of high pressure, referred to as a heat dome, slipped even farther northward, spanning from northern Siberia into the Central Arctic ocean - smack dab over much of the sea ice pack. In fact, the high-altitude "heat dome" is more intense than any other on the planet, and likely anything forecast to develop globally in the coming weeks. The dome of heat has also helped to deflect inclement weather and storm systems away from Siberia, with sinking air eroding cloud cover and precipitation.
The alignment of weather systems is just one side of the coin in a world facing the growing impacts and severity of human-induced climate change. This period of unusually mild Arctic weather is only the latest of many such episodes in recent years as the region rapidly warms in response to increasing amounts of greenhouse gases in the atmosphere. The Arctic as a whole is warming at more than twice the rate of the rest of the world, owing to feedbacks in the climate system, and this is leading to sweeping changes in the way of life for the area’s 4 million residents, as well as a cascade of knock-on effects to ecosystems.
"This heat wave occurs mostly at the area which has been anomalously warm during the whole 2020," said Mika Rantanen, a researcher at the Finnish Meteorological Institute, via email. "It could be that lack of snow/dry soils can play a role, so they now favor high temperatures as the [solar] energy [is] not consumed [by] melting of snow."
"One thing which I found noteworthy is that Russia just experienced a record-warm winter. And [it] looks like the warmth or heat still continues."

© 1996-2020 The Washington Post.
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    Ученые Сколтеха и МФТИ вырастили на поверхности алмаза тонкую пленку хлорида натрия с необычной гексагональной структурой, доказав тем самым возможность существования двумерных и при этом стабильных атомных структур. Такая пленка может служить диэлектриком, отделяющим затвор от канала в полевых транзисторах на алмазе, которые могут применяться, например, в телекоммуникационном оборудовании.

Skoltech and MIPT scientists have predicted and then experimentally confirmed the existence of exotic hexagonal thin films of NaCl on a diamond surface. These films may be useful as gate dielectrics for field effect transistors in electric vehicles and telecommunication equipment. The research, supported by the Russian Science Foundation, was published in The Journal of Physical Chemistry Letters.
As graphene, the famous two-dimensional carbon, was experimentally prepared and characterized in 2004 by future Nobel laureates Andre Geim and Konstantin Novoselov, scientists started looking into other 2-D materials with interesting properties. Among these are silicene, stanene and borophene - monolayers of silicon, tin, and boron, respectively - as well as 2-D layers of MoS2, CuO, and other compounds.
Skoltech Ph.D. student Kseniya Tikhomirova, Dr. Alexander Kvashnin of Skoltech and Professor Artem R. Oganov of Skoltech and MIPT together with their colleagues built upon earlier studies of NaCl thin films to hypothesize the existence of an unusual nanometer-thick hexagonal NaCl film on the (110) surface of diamond.
"Initially we decided to perform only a computational study of the formation of new 2-D structures on different substrates, driven by the hypothesis that if a substrate interacts strongly with the NaCl thin film, one can expect major changes in the structure of the thin film. Indeed, we obtained very interesting results and predicted the formation of a hexagonal NaCl film on the diamond substrate, and decided to perform experiments. Thanks to our colleagues who performed the experiments, we synthesized this hexagonal NaCl, which proves our theory," says Kseniya Tikhomirova, the first author of the paper.
Researchers first used USPEX, the evolutionary algorithm developed by Oganov and his students, to predict structures with the lowest energy based on just the chemical elements involved. After predicting the hexagonal NaCl film, they confirmed its existence by performing experimental synthesis and characterization by XRD (X-ray diffraction) and SAED (selected area electron diffraction) measurements. The average thickness of the NaCl film was about 6 nanometers - a thicker film would revert from hexagonal to cubic structure, typical for the table salt we know.
Scientists believe that due to strong binding to the diamond substrate and a wide bandgap, hexagonal NaCl can work well as a gate dielectric in diamond FETs - field-effect transistors that show potential for use in electric vehicles, radars, and telecommunication equipment. Now these FETs typically use hexagonal boron nitride, which has similar bandgap but much weaker binding to the substrate.
"Our results show that the field of 2-D materials is still very young, and scientists have discovered only a small portion of possible materials with intriguing properties. We have a long-standing story starting in 2014 when we described the way cubic NaCl thin films can be split into hexagonal graphene-like layers. This shows that this simple and common compound, seemingly well-studied, hides many interesting phenomena, especially in nanoscale. This work is our first step towards the search for new materials like NaCl but having better stability (lower solubility, higher thermal stability, and so on) which then can be effectively used in many applications in electronics," notes Alexander Kvashnin, senior research scientist at Skoltech.
This work brings us closer to understanding how to control the appearance and, as a consequence, the properties of two-dimensional materials using a substrate. The research also opens the door to more 2-D materials with potential applications in electronics and beyond.

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    Ученые из Якутска, Иркутска и Красноярска изучили диету якутских лошадей, которая помогает им хорошо переносить суровый климат. Ее особенность - в высоком содержании полиненасыщенных жирных кислот в безостном костреце (Bromopsis inermis L.) и овсе обыкновенном (Avena sativa L.), произрастающих в Центральной Якутии. Вегетация у этих растений может идти при нулевой и даже небольшой отрицательной температуре, поэтому лошади могут питаться ими и осенью, накапливая нужные вещества.

A group of scientists from Yakutsk, Krasnoyarsk and Irkutsk investigated the features of the plant diet of Yakutian horses. Using the example of animals from private farms, a significant role of fodder plants growing in Central Yakutia (smooth brome (Bromopsis inermis L.) and common oat (Avena sativa L.)) in the formation of an optimal balance of omega-3 and omega-6 polyunsaturated fatty acids in the liver, muscle and adipose tissues of horses was shown.
The main results of the study have been published in Biomolecules.
The Yakutian horse, distributed in the territory of the Republic of Sakha, was bred under the strong influence of natural selection. The animals are notable for their short stature, dense muscular build and long hair with thick undercoat. Such appearance features are fully consistent with the harsh northern conditions. The horse is kept unstabled most of the year and graze on vegetation that is under deep snow cover.
"During a short Yakutian summer cereals grow, reach maturity and give seeds. During this period local animals, including Yakutian horses, feed on them. In autumn, repeated vegetation begins and new shoots appear. It often occurs at low positive and small negative temperatures. Scientists from the Institute for Biological Problems of Cryolithozone of Siberian Branch of the Russian Academy of Sciences (SB RAS) and Siberian Institute of Plant Physiology and Biochemistry, SB RAS, proved that due to this hardening, cereals accumulate a significant amount of useful compounds, i.e. polyunsaturated fatty acids (in particular, alpha-linolenic acid). They, in turn, precede the synthesis of irreplaceable long chain omega-3 acids, without which animals and people cannot fully function. It was shown that these acids help plants to ensure fluidity of cell membranes, which is necessary to maintain the cell in a working state.
The muscle and fat tissue of horses, like many animals, reflect the fatty acid composition of the food eaten. Yakutian horses are no exception. Feeding on cereals enriched with alpha-linolenic acid, they accumulated it in their tissues. An interesting fact is that mainly linoleic and arachidonic acids were found in the horse liver. These are polyunsaturated fatty acids from the omega-6 family. Arachidonic acid is most likely synthesized in the tissues of horses, since food sources of this acid could not be found," said Olesia Makhutova, study’s co-author, Doctor of Science (in Biology), assistant professor of the Chair of Water and Terrestrial Ecosystems, SibFU, senior fellow of the Institute of Biophysics, SB RAS.
The researcher noted that samples were taken from populations living in various regions of the Sakha Republic, including in the Oymyakon ulus, which is the coldest point in the Northern Hemisphere. It was the extreme temperature for all living things (up to -60 °C) that prompted scientists to think that the antifreeze qualities of fatty acids obtained from local cereals serve Yakutian horses well.
"We assume that the accumulation of alpha-linolenic acid in the body allows these animals to competently spend their stored fat. It is no coincidence that they look so well-fed. Without sufficient fat reserves and finely tuned mechanisms of its expenditure, horses cannot survive the Yakutian winters," commented the scientist.
It is noted that today horse meat in Yakutia is considered to be the main source of animal protein and fat. The Yakutian cow, once widespread, has become small in numbers and needs to be restored, so the needs of the indigenous population for meat are provided by horses.
"The dietary value of the Yakutian horse meat is very high precisely due to the ideal balance of polyunsaturated omega-3 and omega-6 acids, 1:1 ratio of these acids is ideal for us, but civilization is steadily shifting the balance towards the predominance of omega-6 due to the dominance of vegetable oils, cheap pork and fast food in our daily diet. We also need omega-6 acids, but in combination with the omega-3 partners, which are found mainly in fatty fish. The horse meat we tested is also very good, especially for child nutrition and the diet of people suffering from cardiovascular diseases. If the population of Yakutia starts consuming mass-market products, which are now imported abundantly into the republic, and makes a choice in favor of, let us say, semi-finished pork products, this may drastically affect people’s health. This is just the case when you should not change a time-tested balanced die," concluded Olesia Makhmutova.

© Copyright IndiaEducationDiary, 2020.
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    Российские ученые провели исследование с целью определить, каким образом запускается адаптивный иммунный ответ после заражения вирусом SARS-CoV-2.

The global COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is spreading over the world. However, not much is known about how the adaptive immune response kicks in following the viral challenge. This knowledge is crucial to predicting the efficacy of a vaccine and estimating the chances of reinfection.
Now, in new research published on the preprint server medRxiv, Russian scientists aimed to understand the determinants of adaptive immune response to SARS-CoV-2. To do this, they assayed both antibody and T-cell reactivity to SARS-CoV-2 antigens in COVID-19 convalescent patients and healthy donors sampled before and during the pandemic.
The Importance of Antibody Tests
Based on current knowledge, it is thought that viral clearance occurs because of an antibody response. A variety of antibody tests are therefore being developed to detect specific antibodies directed against the virus and to use such tests for immunological surveillance to estimate the seroprevalence of COVID-19.
Another important application would be the development and use of monoclonal antibodies and convalescent plasma to treat severely ill COVID-19 patients. Monoclonal antibodies against the Spike protein have been found to neutralize SARS-CoV-2 even when inoculated at high doses into experimental animals. On the other hand, almost a third of convalescent patients show negligibly low levels of such neutralizing antibodies, which could mean other immune components are also necessary to clear the virus from the host by immune mechanisms.
The Potential Role of T Cells in Viral Clearance
T cells are strongly implicated in the respiratory clearance of the earlier SARS-CoV, with long-lived memory T cells being observed to be present in 50% of convalescent patients even 12 months after infection. Another study showed the presence of CD8 cells targeting the dominant antigenic site of the S protein of a modified SARS-CoV strain, and that these cells prevented fatal infection in old mice. Other researchers have demonstrated that immunity can be transferred via specifically-primed CD8 or CD4 cells, or by the use of a peptide-pulsed dendritic vaccine. These suggest the adequacy of T cells to clear the virus even without antibody production or activation of the innate immune system. The CD4 cells may lead in this response, with low CD4 levels causing slower viral clearance, but not low CD8 levels. When CD4 cell responses were satisfactory, the SARS infection generally had a good outcome.
Human T Cells Response to COVID-19
In human studies, the adaptive immune response is slow to develop in the case of severe SARS-CoV, and virus clearance is delayed. Low T cell counts are associated with more severe disease. T cells also help form a memory response. Thus, even four years later, these patients had CD4 and CD8 cells that secreted the inflammatory chemical interferon-gamma when stimulated by pools of peptides from the S, N, and M proteins of the virus.
Among all the SARS-CoV antigens, the S protein stimulates the highest level of antibody production. The epitopes of this protein that bound to CD4 and CD8 T cells were identified. Two of these epitopes binding to CD8 cells were presented by the MHC II molecule HAL-A*02:01 and stimulated a specific response in patients who had recovered from SARS but not healthy individuals. Many other T cell epitopes in the M and N proteins of the virus have also been identified.
T Cells in COVID-19
There is now much evidence that the T cell response is crucial to controlling COVID-19. Elevated CD8 T cell counts in the lungs predict a favorable disease course. Again, the presence of T follicular helper cells and activated CD8 T cells in the blood of recovering patients with negative PCR tests, indicating viral clearance, shows their possible role in the immune response. If the CD8 cells are exhausted, on the other hand, the outcome of the disease may be poor.
It is thought that the immune memory cells can protect against reinfections with SARS-CoV-2, based on primate studies. The T cells in recovering patients react to stimulation by the pools of peptides from the viral proteins. This was especially true of the Th1 response in CD4 cells, induced by the S protein of this virus.
An interesting finding was the reactivity of CD4 cells to SARS-CoV-2, both in recovering and in healthy individuals. The scientists attribute this to "T cell cross-reactivity". In the absence of experimental data on the T cell targets, the current study aims to understand the immune response to the virus; to identify the structure, clonal nature, and specific epitopes of the T cell-mediated immune cellular response to the S protein.
SARS-CoV-1-Specific T Cells in Healthy Uninfected Donors
The researchers found that there were specific T cells but not antibodies in healthy blood donors from whom samples were taken during the pandemic. This probably rules out the chances of past asymptomatic COVID-19 in this group. Both CD4 and CD8 T-cells specific for S-protein were found in this group. This could mean some patients were exposed to the infection but did not develop overt symptoms. In the convalescent patient group, there were T cells directed against the S protein. The CD4 cells were mostly memory cells and a few effector cells, while the CD8 cells were mostly effector cells. However, the number of activated CD4 cells was significantly greater, as was the level of PD-1 expression by interferon-secreting CD4 cells, in the convalescent patient group compared to the healthy donors. Most of the IgG antibodies in convalescent COVID-19 patients were directed against one or more of the viral antigens. Nonetheless, there were antibodies against all three antigens, S. N and M. The T cell response varied, with no clear relationship between the T cell and humoral response. T cells in this group reacted to the recombinant S protein but not to peptide pools derived from the S protein, with equal responses in CD4 and CD8 cells. All the patient serum samples reacted to one or more of the viral proteins, M or N, with either CD4 or CD8 responses.
Immune Response to Two Epitopes Detects Past COVID-19
Among the 31 convalescent serum samples, there were 14 with a common MHC allele. Just two of 13 epitopes (called RLQ and YLQ), reported to be presented by this MHC molecule and to induce a robust immune response, were recognized by T cells, in 12/14 and 10/14 samples. They were not recognized by samples from healthy donors, showing that these cells came from the memory cell population.
Based on T cell receptor (TCR) analysis, these cells belonged to a large number of antigen-specific clones, with a median of 115 CD4 and 18 CD8 cell clones. There were markedly more clones of cells recognizing one of the two epitopes above than the other (median 37 vs. 8). Hardly any clones recognized both the epitopes, suggesting these clones may be localized to the peripheral tissue rather than the peripheral circulation.
TCR Sequence Motifs Prominent and Shared Across Individuals
Some variable genes are used far more frequently by the TCRs for these two epitopes compared to the control TCRs. There is also a set of three distinct motifs from the CDR3 alpha and beta chains, respectively, each containing over ten very similar sequences from the epitope-specific T cells. All these motifs were found in most of the donors but without any pairing pattern between the motifs of different chains. This suggests this is a public response even while being diverse.
Finally, the TCR repertoire analysis showed that there were groups of homologous TCR sequences that arose from an antigen-specific response. This showed 9 CD4 and 8 CD8 clusters shared between stimulated T cells from multiple healthy donors. One of these has matching TCR sequences with those found in T cells specific to one of the two epitopes above and is also present in peripheral blood mononuclear cells (PBMCs). Thus, this set of sequences is shared by both the interferon-producing CD8 cells and the PBMCs.
What Does This Study Show About COVID-19 Seropositivity?
The researchers draw the following conclusions:
Some healthy uninfected donors carry SARS-CoV-2-specific T cells, and these are increased in donors sampled during the pandemic, though there are no antibodies. This indicates that some donors could have been exposed to the virus, but the cross-reactive antibodies against other CoVs protected them from the full infection. The study helps outline the cellular immune response to COVID-19. More research will be needed to fill in the gaps, helping evaluate and develop a potent vaccine against this virus.
Important Notice:
medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.

AZoNetwork, © 2000-2020.
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    HPCwire / May 28, 2020
    Russian Supercomputer and Three Chinese Universities Join the Good Hope Net Project to Combat Coronavirus
    Для быстрой разработки лекарственных средств для диагностики и терапии коронавирусной инфекции COVID-19 была сформирована международная команда ученых из России, Финляндии, Италии, Канады и Китая с высокоприоритетным доступом к суперкомпьютеру «РСК Торнадо», развернутому в Межведомственном суперкомпьютерном центре РАН (МСЦ РАН).

China’s Hunan University, Shanghai Jiao Tong University and Xiamen University have joined an international science group named The Good Hope Net. The scientists from Russia, Finland, Italy, Canada and China have a high priority access to RSC Tornado supercomputer deployed at Joint Supercomputing Center of Russian Academy of Sciences (JSCC RAS) for studying methods to fight against the COVID-19 coronavirus infection. This project aims to develop medicine for diagnostics and therapy against the coronavirus contagious disease that became the cause of the global pandemic.
The Good Hope Net team uses a recently upgraded cluster system based on 2nd Generation Intel Xeon Scalable processors, which has been deployed by RSC Group, the leading Russian and worldwide well known solution provider for high-performance computing and data storage-on-demand.
The coronavirus pandemic in 2020 threatens lives of many people and hinders economic and social activity in multiple countries all over the world. As a result, it attracted significant attention of many research groups. Finding treatments to prevent and mitigate the negative impact of COVID-19 is the highest priority in the worldwide scientific community now. The international and multidisciplinary The Good Hope Net project takes advantages of the latest advances in experimental physics, chemistry, and biology to investigate the life cycle of the virus and to target specifically its specific proteins.
Sophisticated simulation methods require supercomputing power to study all details of the interaction between the Spike-protein on coronavirus surface and the human protein ACE2 which is known to be the entry point for SARS and SARS-2 coronaviruses. It will help to complete all research stages within a limited amount of time.
International project to fight the global pandemic
"Rapid global spread of COVID-19 coronavirus infection pandemic has shown that there are no clear global emergency response plans against threats to humankind caused by new viruses. One of the obvious shortcomings is the lack of technologies for quick development of medicines for diagnostics and therapy. To help solving this problem, an international team of scientists - from Russia, Finland, Italy and Canada - was formed. We all have different competences, knowledge, skills and resources. Our geographically distributed team includes virologists, biologists, chemists, mathematicians and physical scientists. The international cooperation is extremely important to achieve quick progress and rapidly react to the ever-changing situation with global COVID-19 pandemic. We hope that our research will actually help to fight spread of such infections," explains Anna Kichkailo, Head of Laboratory For Digital Controlled Drugs and Theranostics at the Krasnoyarsk Federal Science Center of RAS, Head of the Laboratory for Biomolecular and Medical Technology of the V.F. Voyno-Yasenetsky Krasnoyarsk State Medical University.
The Good Hope Net project team consists of:
• Laboratory for Digital Controlled Drugs and Theranostics and Laboratory of Physics of Magnetic Phenomena, Kirensky Institute of Physics at the Federal Science Center, Siberian Branch of Russian Academy of Sciences (KIP FSC SB RAS, Krasnoyarsk, Russia),
• Laboratory for Biomolecular and Medical Technology, V.F. Voyno-Yasenetsky Krasnoyarsk State Medical University (KSMU, Krasnoyarsk, Russia) - project coordinator,
• Laboratory of Chemical Cybernetics, Department of Chemistry at Lomonosov Moscow State University (MSU, Moscow, Russia),
• Laboratory for Computer Simulation of Biomolecular Systems and Nanomaterials at N. M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences (IBCP RAS, Moscow, Russia),
• Organic Synthesis Laboratory, Institute of Chemical Biology and Fundamental Medical Science, Siberian Branch of the Russian Academy of Sciences (ICBFM SB RAS, Novosibirsk, Russia),
• Nanoscience Center and Department of Chemistry, University of Jyväskylä, Jyväskylä (Finland),
• Institute for Experimental Endocrinology and Oncology (IEOS), part of National Research Council (CNR), Naples (Italy),
• Department of Molecular Medicine and Medical Biotechnologies, Department of Pharmacy, Federico II University of Naples (Italy),
• The Bioanalytical and Molecular Interaction Laboratory, Department of Chemistry and Biomolecular Sciences, University of Ottawa (Canada),
• The Molecular Science and Biomedicine Laboratory, Hunan University (China),
• School of Medicine, Institute of Molecular Medicine, Shanghai Jiao Tong University (China),
• Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian (China).
Computer design of medicine against COVID-19
"We aim to use molecular simulation to create a computer model of a medical drug with selective interaction with receptor-binding domain of Spike protein of SARS-CoV-2 coronavirus strain. The most promising specific binding agents to be used for diagnostics (identification of virus particles in saliva) and development of virus treatment drugs preventing ingress of infection. The results of theoretical calculations and computer simulation will be experimentally tested on proteins, viruses and cells," summarizes Anna Kichkailo.
Supercomputer simulations are used to study details of interaction between Spikeprotein on coronavirus surface and the human protein ACE2 (angiotensin converting enzyme 2). ACE2 is known to be the entry point for SARS and SARS-2 coronaviruses. By blocking its interaction with the spike protein, it is possible to reduce virus activity in human body. Massive molecular dynamics and quantum chemistry calculations of virus and human proteins are using to estimate protein binding energies. The results of simulations will be used to design aptamers that will bind with virus proteins better than ACE2. Molecular docking and molecular dynamics methods will be used to create a library of promising aptamers and to estimate the strength of their interaction with virus proteins. Binding energies for the most promising aptamers will be refined with quantum chemistry methods. A lot of supercomputing resources is required to complete all these research stages within limited amount of time.
The need for supercomputers
Developing drugs to mitigate the disease and reduce the risk of the severe complications is one of the most important tasks before coronavirus vaccine will be widely adopted. Computer simulations deliver valuable information on the viral activity on atomic level and they can be used to predict the efficiency of potential drugs. Such calculations are extremely demanding and can be done only with the most powerful supercomputers.
HPC systems are widely used in simulations of biochemical processes. The simulations help to reduce the number of experiments that would otherwise be needed to get same results. Leading global pharmaceutical and research centers use molecular modeling at the initial steps of drug development, when a massive number of chemical substances have to be investigated for specific activity.
Experimental data about the coronavirus activity on molecular level is very limited and have been produced in vitro. For example, the viral protein structure corresponds to the crystallized protein and not to a virus in solution. Moreover, there is not enough experimental data on complexes between virus and human proteins or virus proteins and potential drugs. On the other hand, supercomputer calculations can give all the structural data and the details of binding process. Therefore, the computing part is critically important, as well as subsequent experimental verification.
Upgraded MVS-10P OP supercomputer at JSCC RAS
The Joint Supercomputer Center of the Russian Academy of Sciences is one of the most powerful Russian supercomputing centers in the fields of science and education. JSCC RAS staff includes qualified scientists, programmers and engineers. Over 150 groups of researches use JSCC resources for fundamental and applied research tasks. Total peak performance of JSCC RAS computing facilities exceeds 1.3 Petaflops (petaflops - quadrillion of floating-point operations per second, or 1000 teraflops). Five JSCC RAS cluster systems are included in the Top50 list of the most powerful Russian supercomputers.
After the recent upgrade of MVS-10P OP at the end of 2019 completed by the Ministry of Science and Highest Education of the Russian Federation, its peak performance reached 771 Teraflops (teraflops - trillion of floating-point operations per second). Adding a new segment based on the modern high-performance 2nd Generation Intel Xeon Scalable processors allowed to achieve the significant performance increase of y 209 Teraflops. MVS-10P OP is based on RSC Tornado, an universal ultrahigh-dense and energy efficient platform developed by RSC Group (Russia).
"By regularly upgrading JSCC RAS computing resources we get new R&D opportunities, provide RAS and academic researches with powerful resources for various complex fundamental and applied tasks and improve overall efficiency of Russian scientists," said Gennady Savin, Academician of RAS and Science Head of the Joint Supercomputer Center of the Russian Academy of Sciences.
Researchers access resources of JSCC RAS using the National Research Network (NICS) of the Ministry of Science and Highest Education of the Russian Federation.

© 2020 HPCwire. All Rights Reserved.
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    Aysor / 29/05/2020
    Russian scientists offer new version of Moon’s origin through computer modelling
    Российские ученые смоделировали новую версию возникновения Луны, согласно которой она могла возникнуть параллельно с Землей как двойная система в результате фрагментации облака пылевых частиц.

Russian scientists confirmed through computer modelling that the Moon could have originated concurrently with the Earth rather than as a result of our planet’s collision with a celestial body, Roscosmos Executive Director for Long-Term Programs and Science Alexander Bloshenko told TASS.
"In recent years, Russian scientists put forward and substantiated a new concept, under which the Moon formed simultaneously with the Earth as a binary system resulting from the fragmentation of a cloud of dust particles," Bloshenko said.
This hypothesis was confirmed by the results of computer modeling, he added.
As the Roscosmos specialist noted, the Moon is only 13 million years younger than the Earth whose age is estimated at 4.5 billion years.
Until recently, the most reliable version of the Moon’s origin was the hypothesis that it emerged as a result of the Earth’s collision with a large celestial body comparable to Mars in its size, the specialist recalled.
As a result, the enormous mass of the terrestrial matter and partially the material of the celestial body, which had collided with the Earth, melted and was thrown into the near-Earth orbit where it formed a compact body which became the Moon, he said.

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    Исследователи Дальневосточного федерального университета и Института химии ДВО РАН создали сорбент на основе порошка натрий-вольфрамовой бронзы, очищающий воду от радиоактивных элементов цезия и стронция.

Scientists from Far Eastern Federal University (FEFU) in collaboration with colleagues from the Institute of Chemistry FEB RAS come up with a smart technology for the synthesis of sorbent based on a "tungsten bronze" compound powder (Na2WO4) aimed to purify industrial and drinking water from hazardous radionuclides cesium (137Cs), and strontium (90Sr), as well as for effective processing of liquid radioactive waste. A related article appears in the Journal of Materials Science.
Until recently, the most reliable version of the Moon’s origin was the hypothesis that it emerged as a result of the Earth’s collision with a large celestial body comparable to Mars in its size, the specialist recalled.
The new sorbent is appropriate when the concentration of hazardous radioactive elements is extremely higher than the acceptable level, i.e. for processing of liquid radioactive waste from nuclear plants and to eliminate the consequences of technological accidents.
Until recently, the most reliable version of the Moon’s origin was the hypothesis that it emerged as a result of the Earth’s collision with a large celestial body comparable to Mars in its size, the specialist recalled.
The development resolves one of the pressing problems of modern radioecology, which is to completely or down to the level of regulative standards extract the hazardous radioactive elements cesium (137Cs) and strontium (90Sr) capable of accumulating in the body, replacing potassium and calcium.
Until recently, the most reliable version of the Moon’s origin was the hypothesis that it emerged as a result of the Earth’s collision with a large celestial body comparable to Mars in its size, the specialist recalled.
The waste sorbent is supposed to convert into high-density ceramics with subsequent safe disposal.
Until recently, the most reliable version of the Moon’s origin was the hypothesis that it emerged as a result of the Earth’s collision with a large celestial body comparable to Mars in its size, the specialist recalled.
"We propose to apply a sorbent in several ways. First, in the static version, granules based on tungsten bronze powder can simply be introduced into the volume of contaminated water bodies. Second, in a dynamic mode, porous sorbent tablets can be a component of flow filters. The high filtration efficiency registered by calculation methods determining the residual amount of radionuclides in sorbent-purified solutions, as well as the number of radionuclides retained in the sorbent body. We appreciate the Institute of Chemistry FEB RAS for the partial development of these methods in the frame of state assignment. We have studied physicochemical properties of the sorbent material via high-class Shimadzu equipment (Japan) and do believe that the operational properties of the material are up to analogs produced by more expensive technologies. Thus, we hope that our synthesis method will be recognized by the industry as most practical and technologically effective," says Arthur Drankov, a member of the creative team, postgraduate student of FEFU School of Natural Science.
Until recently, the most reliable version of the Moon’s origin was the hypothesis that it emerged as a result of the Earth’s collision with a large celestial body comparable to Mars in its size, the specialist recalled.
The scientist points out that, if regenerated, the sorbent can serve five or more cycles. However, re-using of "tungsten bronze" sorbents is not the main idea, given that its absorbing abilities with respect to 137Cs and 90Sr radionuclides are well known.
Until recently, the most reliable version of the Moon’s origin was the hypothesis that it emerged as a result of the Earth’s collision with a large celestial body comparable to Mars in its size, the specialist recalled.
The advantage proposed by researchers of FEFU School of Natural Science and FEB RAS is to convert waste granules or sorption tablets to high-density ceramics for further safe disposal during the half-life of hazardous radioactive elements. For cesium, this period is about 30 years, for strontium is about 29 years.
Until recently, the most reliable version of the Moon’s origin was the hypothesis that it emerged as a result of the Earth’s collision with a large celestial body comparable to Mars in its size, the specialist recalled.
Scientists will develop a transforming-to-ceramics technology at the next stage of the work supported by a grant of the Russian Foundation for Basic Research (Grant chief is I. G. Tananaev, Director of FEFU School of Natural Science, corresponding member of the Russian Academy of Sciences).
Until recently, the most reliable version of the Moon’s origin was the hypothesis that it emerged as a result of the Earth’s collision with a large celestial body comparable to Mars in its size, the specialist recalled.
Researchers suggest that the total outcome will be a cost-effective technology that guarantees environmental safety when dealing with radioactive waste.

Copyright © 2020 by the American Association for the Advancement of Science (AAAS).
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    Сотрудники НИТУ «МИСиС» синтезировали новый материал с ультравысокой температурой плавления - нестехиометрический карбонитрид гафния. Точную температуру плавления ученые пока не определили, но она вполне может преодолеть порог в 4000 градусов Цельсия. Такие материалы особенно востребованы в аэрокосмической отрасли.

Scientists at a Russian university have created a new material capable of withstanding higher temperatures than space rockets face as they traverse Earth’s atmosphere. Scientists have just unveiled the world’s most heat-resistant material. An invention that space agencies around the world had been searching for many years as a solution to future futures future reusable space planes.
The researchers of the National University of Science and Technology (NUST) MISIS in Russia they have managed to create a new ceramic material whose melting point is the highest known so far. Thanks to its composition this new material can withstand temperatures above 4,000 °C.
The world of aviation, especially the space aviation sector, is in luck with this news. Agencies like NASA and ESA have been working for years looking for the perfect design to create reusable shuttles and be able to carry and bring astronauts and cargoes at the lowest possible cost.
The history of NASA gives for many reports but it is rarely spoken of the great contribution they have made to the improvement of life on Earth.
Building a new rocket or much of it on each mission is a huge cost to the budgets of these space agencies. Every time a rocket must go through the atmosphere, the surface of the wings can be observe temperatures above 2,000 °C, even 4,000 °C at the edge of these.
For this reason, the researchers were encouraged to study new materials that could resist these temperatures. The team chose the triple combination of hafnium, carbon and nitrogen, that is, the hafnium carbonitride (Hf-C-N).
To find out if the resulting formula was what they were looking for, they compared the material with hafnium carbide. Veronika Buinevich, a researcher at NUST MISIS, explains in the statement: "It is difficult to measure the melting point of a material when it exceeds 4000 degrees Celsius. Therefore, we decided to compare the melting temperatures of the synthesized compound and the original champion, hafnium carbide."
They connected the materials to a battery that used molybdenum electrodes. The results revealed that the material created, carbonitride had a higher melting point than hafnium carbide. Although it is able to withstand temperatures above 4,000 degrees Celsius, the laboratory has not yet been able to test it above that temperature for safety reasons.
The creators will continue working to know all the possibilities of this new material and see how it responds to a laser or electrical resistance.

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