Октябрь 2017 г. |
Российская наука и мир (по материалам зарубежной электронной прессы) |
EurekAlert / 3-Oct-2017
Chemists teach computer program to model forces between atoms accurately
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С помощью системы машинного обучения российские химики научили компьютер предсказывать поведение атомов в различных условиях, обучаясь на простых примерах, просчитанных при помощи классических методов квантовой механики.
A team of researchers from MIPT, Skoltech, and Dukhov Research Institute of Automatics, led by Artem Oganov, used a machine learning technique to model the behavior of aluminum and uranium in the liquid and crystalline phases at various temperatures and pressures. Such simulations of chemical systems can predict their properties under a range of conditions before experiments are performed, enabling further work with only the most promising materials. The research findings were published in the journal Scientific Reports.
Computer chemistry
Rapid advances in science over the last 100 years have resulted in the discovery of an astonishing number of organic and inorganic compounds, protein and lipid structures, and chemical reactions. But with all these new structures and molecules, an increasing amount of time is necessary to study their makeup, biochemical and physical properties, as well as test the models of their behavior under various conditions and their possible interactions with other compounds. Such research can now be accelerated using computer modeling.
The force field approach is the currently dominant modeling technique. It makes use of a set of parameters describing a given biochemical system. These include bond lengths and angles, and charges, among others. However, this technique is unable to accurately reproduce the quantum mechanical forces at play in molecules. Accurate quantum mechanical calculations are time-consuming. Besides, they only enable predictions of the behavior of samples that are at best several hundred atoms large.
Machine learning approaches to molecular modeling are of great interest to chemists. They enable models that are trained on relatively small data sets obtained by means of quantum mechanical calculations. Such models can then replace quantum mechanical calculations, because they are just as accurate and require about 1,000 times less computing power.
Progress made by machine learning tools modeling interactions between atoms
The researchers used machine learning to model the interactions between atoms in crystalline and liquid aluminum and uranium. Aluminum is a well-studied metal whose physical and chemical properties are known to scientists. Uranium, by contrast, was chosen because there are conflicting published data on its physical and chemical properties, which the researchers sought to define more accurately.
The paper details their study of such material properties as the phonon density of states, entropy, and the melting temperature of aluminum.
"The magnitudes of interatomic forces in crystals can be used to predict how atoms of the same element will behave under different temperatures and in a different phase," says Ivan Kruglov from the Computational Materials Design Laboratory at MIPT. "By the same token, you can use the data on the properties of a liquid to find out how the atoms will behave in a crystal. This means that by finding out more about the crystal structure of uranium, we can eventually reconstruct the entire phase diagram for this metal. Phase diagrams are charts indicating the properties of elements as a function of pressure and temperature. They are used to determine the limits to the applicability of a given element."
To make sure that the data yielded by computer simulations is valid, they are compared to experimental results. The method used by the researchers was in good agreement with prior experiments. The information obtained with the approach based on machine learning had a lower error rate, compared to the modeling techniques using force fields.
In this study, the authors improve on their 2016 results in terms of the speed and accuracy of atomic system modeling using machine learning.
Copyright © 2017 by the American Association for the Advancement of Science (AAAS).
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Popular Mechanics / Oct 4, 2017
How a Russian Scientist's Sci-Fi Genius Made Sputnik Possible Sputnik, the first satellite to reach space, launched 60 years ago today. Konstantin Tsiolkovsky made it possible - even though it launched 22 years after his death.
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60 лет назад был запущен в космос первый спутник. Константин Циолковский умер 22 годами ранее, но без него этот запуск, возможно, не состоялся бы. Ученый-самоучка, он оказал сильнейшее влияние на поколение, начавшее осваивать космос, а его фантастические идеи воплотились десятилетия спустя - ракеты, воздушные шлюзы, скафандры, орбитальные станции, выход в открытый космос. Части же из них, таким как пилотируемые полеты на другие планеты и освоение дальнего космоса, еще только предстоит осуществиться.
On May Day 1935, thousands gathered in Red Square to celebrate the glorious Soviet state. It was near the end of the proceedings when the feeble voice of 77-year-old Konstantin E. Tsiolkovsky, the preeminent Soviet astrophysicist and a national hero, echoed through the square from speakers atop Lenin's Mausoleum:
"Now comrades, I am finally convinced that a dream of mine - space travel - for which I have given the theoretical foundations, will be realized. I believe that many of you will be witnesses of the first journey beyond the atmosphere. In the Soviet Union we have many young pilots... (and) I place my most daring hopes in them. They will help to actualize my discoveries and will prepare the gifted builders of the first space vehicle. Heroes and men of courage will inaugurate the first airways: Earth to Moon orbit, Earth to Mars orbit, and still farther; Moscow to the Moon, Kaluga to Mars!"
The square erupted in cheers, led by none other than the country's leader Joseph Stalin.
Twenty-two years later, the Soviet Union launched the first artificial satellite into space aboard the R-7 rocket. After its flight into space on October 4, 1957 - 60 years ago today - Sputnik-1 quickly entered into legend, and struck fear in the United States about falling behind in the space race. But such a momentous launch likely couldn't have happened without Tsiolkovsky, a mathematician, founding father of modern rocketry, and a science-fiction visionary that even inspired Arthur C. Clarke.
"It's very hard to overestimate the impact Tsiolkovsky had on the generation that built Sputnik," says Asif Siddiqi, space exploration scholar and professor of history at Fordham University and author of The Red Rockets' Glare.
While he remains unknown to many Americans, Tsiolkovsky's influence on Russian space exploration is still felt today.
Born to dream
Tsiolkovsky was a man of humble beginnings, a fact that the Bolshevik government would emphasize in later years. He was born in 1857 in the small town of Kaluga, 110 miles southwest of Moscow. At ten, he contracted scarlet fever which left him nearly deaf. Due to his inability to hear, school proved difficult and he dropped out. Later, Tsiolkovsky would take great pride in his self-prescribed eduction, saying "besides books, I had no other teachers."
In his late teens, he moved to Moscow to study at the world-famous Rumyantzev Library (today, the Russian State Library). That's where he discovered the works of French writer Jules Verne. Many of Verne's space stories, like "From Earth to the Moon" and "Off on a Comet," were growing in popularity around the world, and Tsiolkovsky became entranced by the seemingly fanatical descriptions of rocket propulsion, space travel, and visiting the moon.
Tsiolkovsky would go on to prove that a giant cannon, like the one used in Verne's "From Earth to the Moon," would inevitably killed its passengers due to the extreme force of acceleration. But Tsiolkovsky had his own theories of propulsion, ones that wouldn't kill the aspiring cosmonaut. He thought someone could escape Earth using liquid fuel and the correct ratio of thrust, velocity, and mass. He eventually fleshed out this theory, which became known as "Tsiolkovsky's Equation" or the "ideal rocket equation." The calculations are likely the first scientifically sound proposal for the use of rockets for space travel and form the very foundation of modern-day rocket science.
The power of a sci-fi mind
Taking a cue from Verne, Tsiolkovsky created science-fiction stories of his own, hoping to spread the science behind his "unbelievable" ideas. In 1892's "On the Moon," the main character is in suffering from a fever dream where he imagines that he and a friend are on the moon. He describes the weightlessness, cold, and darkness of being on the moon, and often describes things in such detail that it reads more like a lecture.
For example, when the friend explains why things weigh less on the moon, Tsiolkovsky writes, "a 30-lb weight is only showing 5 lbs. This means that the force of gravity is reduced by a factor of 6...This exact scale of gravity exists on the surface of the moon, a result of its smaller volume and the lesser density of its composition."
His later works, like 1895's "Dreams of the Earth and Sky,"described humanity's colonization of space, including drawings of asteroid mining and greenhouses in space, and 1932's "Comic Philosophy" discussed humanity's future traveling among the stars.
"[Tsiolkovsky's stories] weren't aesthetically beautiful or meant as high literature," Siddiqi says. "They were meant as pedological tools to understand space travel."
Tsiolkovsky was also a true believer in a utopian philosophy known as Russian cosmism. The thinking went that everything in the universe - from humans to the tiniest grain of sand - has some level of consciousness. When humans die, they simply drift off into space ready to reanimate on a planet far away from Earth.
Particularly in his later years, Tsiolkovsky wrote volumes on cosmism, combining his scientific work with his space theology. When looking at Tsiolkovsky, someone who's life was punctuated with perpetual loss, it's easy to see why he looked for hope in his life's work and the cosmos above.
Eventually, this philosophy lead him to write that "the Earth is the cradle of mankind, but one cannot live in the cradle forever" This phrase would go on to be quoted by another famous science educator - Carl Sagan.
A revolutionary legend
While his writings and research are popular in Russia today, for most of his life Tsiolkovsky worked in obscurity. His meditations on liquid propellants, off-Earth colonization, and "celestial castles," were often ignored by the scientific community. This was because of his lack of formal education, his few connections to the autocracy, and the seeming outlandishness of his ideas.
However, that changed when 1917's Russian Revolution toppled the tsar. Tsiolkovsky's homegrown narrative and Soviet-centric ideology were perfect fodder for a new government looking to emphasize national pride. In the 1920s, when Tsiolkovsky was already in his mid-60s, millions of copies of his earlier works were printed and used as propaganda tools for a totalitarian state trying to prove its superiority.
According to his memoirs, Tsiolkovsky wrote of his socialist leanings even prior to the revolution and blamed the tsar for his research's lack of acceptance. "He was a dedicated socialist... his personal philosophy was Soviet socialism," says Tsiolkovsky biographer Daniel Shubin, "He wasn't forced into doing any of this. He believed in a lot of the Marxist concepts."
It was during this time of the 1920s and 30s, when key figures of the Sputnik space programs were children, that Tsiolkovsky became a mythical figure telling the Russian people exploring space was possible. Just a few decades later, many people who saw and heard him were doing just that. With Tsiolkovsky's equation as a building block and his sci-fi stories as inspiration, people like Tikhonravov, Korolev, and Glushko sent the first satellite into space in 1957.
"He deserves to be considered one of the great pioneers of the space age," says Mike Gruntman, who worked in the Soviet space program until 1989 and is now a professor of Astronautics at USC. "His effect on the next generation of people that really implemented (the Soviet space program) is undeniable."
Tsiolkovsky died only a few months after his May Day speech, leaving behind an array of theories, drawings, writings that were not so far off from today's reality - he imagined things like air locks, pressurized suits, and space elevators. His home in Kaluga is now a museum, celebrating the man who taught Russia to reach for the stars.
"All my life I have dreamed that by my work, mankind would at least be advanced a little," Tsiolkovsky wrote close to his death in 1935. When Sputnik was launched 22 years later, mankind advanced much more than a little.
© 2017 Hearst Communications, Inc. All Rights Reserved.
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pv magazine / October 6, 2017
Russian scientists study potential of crystalline solvates for increasing efficiency of perovskite cells
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Минерал перовскит (титанат кальция) - перспективная альтернатива кремнию в создании солнечных панелей. Ученые из МГУ нашли способ повысить эффективность перовскитных батарей, изменяя состав светопоглощающего слоя. Оказалось, что КПД панелей снижается, если в пленках образуются игольчатые или нитевидные кристаллы, что ведет к неоднородности пленок.
Scientists at Moscow, Moscow State University (MSU) have explained how altering the ratio of components forming light absorbing layers of a perovskite solar cell influences the structure of created films and battery efficiency.
The new-found Organic-inorganic perovskites are a type of photoactive element that reacts to light. Researchers have discovered a whole group of compounds, every one of which is a crystalline solvate. These are compounds in which the molecules of the precursor components' solvents are built into their structure. A crystalline film of perovskite is then formed from the solution of the precipitated dissolved components.
The scientists selected and observed three intermediate compounds, which are crystalline solvates of one of the two solvents most used when creating a perovskite solar battery. One of the two compounds had its crystal structure established for the first time
"We have found out that the formation of intermediate compounds is one of the key factors that determines functional properties of the final perovskite layer because perovskite crystals inherit the shape of those compounds. This, in turn, influences the film morphology and solar cell efficiency. It is especially important when creating thin perovskite films, because needle-like or filiform shape of crystals will lead to the film being discontinuous, which will significantly lower the efficiency of the solar cell," said Ph. D., Head of Laboratory of New Materials for Solar Energetic and the principal researcher of the project Alexey Tarasov.
These intermediate compounds, however, are unstable, so the scientists used synchrotron radiation and low temperatures to cool the crystals to the temperature of -173°C. The freezing permitted the scientists to halt the decomposition of the crystals and run the necessary readings to be able to determine the structure of the solvates.
Furthermore, the scientists have researched the thermal stability of the obtained compounds and have managed to calculate the energy of their formation using quantum-chemical modelling. Knowing the formation energy allows to explain why some crystals form when using different solvents.
They also learnt that the ratio of reagents in solution specifically determines which intermediate compound will form in the process of crystallization. The shape of the perovskite crystals formed is determined by the crystal structure of the intermediate compound, which defines the structure of the light-absorbing layer. The output of the solar battery created is in turn influence by this structure.
The results of this study were published in the Journal of Physical Chemistry C.
© PV MAGAZINE 2017.
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Cryptovest / 10 October 2017
Russia to Create a State Blockchain Platform for Knowledge Sharing
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Министерство образования и науки Российской Федерации объявило конкурс на создание и запуск блокчейн-платформы обмена знаниями и управления авторскими правами. Стоимость проекта оценивается в 90 млн рублей.
The Ministry of Education and Science of the Russian Federation has announced a call for bids for the creation and launch of a blockchain platform for knowledge sharing and copyright management. The project cost is estimated at 90 million rubles ($1.56 million).
The Project
According to representatives of the Ministry of Education, the platform should have management and social functions through the integration of blockchain, mutual citation technologies, knowledge sharing and remote inspection of the originality of objects. In the future, the creation of a unified system of digital rules integrated into the platform will create the possibility of organizing a separate virtual ecosystem, which will boost the transparency and effectiveness of the activities of scientists.
The development of a digital platform will:
Ensure timely recognition of new forms of digital description of objects protected by intellectual rights, available for use, including for production;
Simplify the entry of objects into circulation directly by the authors, while allowing scientific and educational organizations see the volume of consumption and determine the value of individual objects;
Form new models of direct and indirect remuneration (monetization) of the subject (author);
Support the review and independent examination of the originality of objects;
Automatically track complex chains of use, processing, and creation of new objects.
The goal of the project is to create a digital platform for knowledge sharing and copyright management based on the aggregation of copyright objects established in higher education institutions and to ensure their turnover based on blockchain technology.
The platform will be tested in at least five universities, with further expansion to a network of higher education institutions of the Association of leading universities (ALU). The introduction of a distributed ledger, as well as the integration of the economic model on the basis of a combination of fiat money and cryptocurrencies, will have to be approved by the expert community of universities (at least three), which have appropriate laboratories, in agreement with the Ministry of Education and Science.
In the course of implementation and approbation of the project, a bank of intellectual property objects (scientific and educational content) in the volume of no less than 10,000 objects will be formed. The whole project is divided into five stages and should be ready by November 2019. Applications for the tender are accepted until October 26, 2017.
Background
As reported by the ministry, the era of a single digital space, in which economically developed countries have entered, transforms the consciousness of society, shifting it to a supranational level. The catalyst for these changes is a set of informational, technological, political and social practices that create, in different parts of the world, points of rapid development of qualitatively different spaces of personal growth. Some examples would be the US, Singapore, and Japan. According to the department, the digital information space is a unique environment for the production, reproduction, and turnover of intellectual property, and, first of all, copyright objects: works of science, literature, and art. Today, the mechanisms for the effective management of intellectual property are lacking, while there is a notable increase in the number of info transactions occurring in the scientific and educational community. Given all this, a "black market" for the knowledge sharing is growing.
According to the Ministry of Education, academic centers and universities are the largest centers to create, reproduce and use copyright objects. In Russia, they are generating, according to various estimates, up to 80% of the scientific and educational content. At the same time, the environment lacks general approaches regarding copyrights.
Based on today's technological capabilities, the solution is to create a blockchain network platform that allows managing digital objects of intellectual property and copyrights.
Interestingly, we reported earlier how Russian schools might start including blockchain lessons in the curriculum, acknowledging the fast-moving trend towards decentralized services and technology.
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ZME Science / October 10th, 2017
Virtual reconstruction shows what the first modern humans to reach Europe looked like
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Ученые из Института этнологии и антропологии РАН при поддержке «Всероссийского Фестиваля науки «Nauka 0+» и студии Visual Science создали трехмерную реконструкцию внешности двух подростков, найденных в 1969 г. в захоронении на верхнепалеолитической стоянке Сунгирь (Владимирская область).
A new computer animation, created using actual specimens and scientifically-accurate reconstruction methods, shows how some of the earliest Homo sapiens of Europe looked like.
When Homo sapiens left Africa and migrated to other continents, they ran into other human species that had come to these lands previously. In certain cases, such as happened with the Neanderthals in Europe, the two groups got very friendly and now, well, now Europeans have 2% Neanderthal genes in their DNA.
So how did the original, un-interbred H. sapiens looked like? Well, thanks to Russian visualization studio Visual Science and the Institute of Ethnology and Anthropology of the Russian Academy of Science, we now have a pretty good idea.
The studio started from the skulls of boy and girl, the first estimated to be about 13 years old, while the girl (believed to be his sister) was likely 2-3 years younger, at the time of death. Their remains, which mark one of the earliest records of modern humans in Europe, were discovered in 1955 near present-day Sungir, Russia, a site which 28,000 to 32,000 years ago served as a settlement for H. sapiens - likely a seasonal hunting camp.
First, Visual Science laser-scanned and took high-definition pictures of the skulls, which were fed into a 3D-modeling program. This software was built following skull-based facial reconstruction techniques developed by Mikhail Gerasimov, a prominent Soviet archaeologist and anthropologist. It's still in use in Russia, Europe, and the United States, and in recent years the Gerasimov method has become even simpler and more accurate, thanks to ultrasound scanning and computer tomography.
Sergey Vasilyev, head of the physical anthropology department at the Institute of Ethnology and Anthropology gave the International Business Times some more details on the methods used: "The anatomical and radiographic research methods used by Gerasimov allowed scientists to not only determine standards for the thickness of soft tissues along the face profile line, but also to reveal patterns in the distribution of the soft tissues' thickness, depending on skull surface morphology development," he told IBT.
"The structure of particular facial elements was determined by individual morphological features of the skull. Gerasimov's successors developed techniques to restore the nose and ears. The degree of reconstruction authenticity was determined by a number of facial reconstruction projects that used the skulls of modern people, whose lifetime portraits were available. The methodology was tested mainly on forensic material."
Despite likely being the ancestors of northern and eastern Europeans today, the two children don't look quite like modern humans. This lack of similarity comes down to evolution - "modern" facial features are believed to have evolved after the stone age, as food processing and cooking allowed our jaws to become smaller and our overall facial anatomy followed suit.
Alongside the bodies, archaeologists also unearthed a large trove of cultural artifacts and ancient household items such as clothing, jewelry, and beads. With them, the studio could also clothe the two children in full (and quite spectacular) garb.
© 2007-2017 ZME Science. All Rights Reserved.
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University World News / 14 October 2017
Minister aims to refocus elite universities programme
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Министр образования и науки России Ольга Васильева предложила радикально сократить количество участников Проекта 5-100 (пять российских университетов должны войти в число сотни лучших в мире) - с двадцати одного до шести. Оставить предполагается университеты, добившиеся наиболее эффективных показателей: Высшую школу экономики, МФТИ, Университет ИТМО, НИЯУ МИФИ, НИТУ МИСиС и НГУ. Представители российского научного и университетского сообщества раскритиковали это предложение, заявив, что обеспечить конкурентоспособность большой страны на международной арене силами всего шести университетов невозможно.
The Russian Minister of Education and Science, Olga Vasilyeva, is proposing to drastically cut the number of participants in the state's 'Project 5-100' aimed at developing world-class universities - in order to improve its chances of achieving its objectives by 2020.
Vasilyeva is seeking to redistribute RUB30 billion (US$524 million) - the remaining sum for the programme - among six domestic universities, instead of the previously planned 21.
Vasilyeva signalled her intention at a meeting of university rectors of institutions participating in the '5-100' programme. She said: "We need to limit the number of universities participating in the programme to only six. These higher education institutions should enter the world top-100 universities, in accordance with the order of Russia's President Vladimir Putin [issued in] May 2012."
But during the meeting she was strongly opposed by the Deputy Prime Minister, Olga Golodets, who urged Vasilyeva to "stick to the letters and spirit" of documents already adopted, and repeatedly tried to prevent the issue being discussed. Golodets said the meeting "was not the best place to discuss this issue".
According to a report in Russia Indicator, Golodets said a sudden change of plan would cause havoc for universities that had signed long-term contracts with foreign teachers and no-one would accept it.
However, after the Deputy Prime Minister left the meeting, Vasilyeva insisted that there was no alternative but to go ahead with her proposal if the programme was to achieve its objectives, according to one observer at the meeting. A final decision would be made by the end of the year.
Vasilyeva said universities that were axed from the programme would have to report on the work already done and the funds spent for the period of their allocation.
"I cannot offer anything else. Because if we do not concentrate on these six universities, there will be no way to implement the order of the president," she said.
In May 2012, President Putin ordered the national government to create conditions for ensuring five Russian universities secure places in the top-100 best universities on the basis of the world's leading university rankings, referring to the Academic Ranking of World Universities or ARWU, and the Times Higher Education and QS World University Rankings.
For this purpose, the Ministry of Education and Science launched the '5-100' programme in 2013, to run until 2020. During two waves of competitive selection 21 universities were allowed to join the programme.
The level of effectiveness of universities in the programme was being measured based on total subsidies, the achievements in world rankings, total volume of R&D activities and the number of scientific publications recorded in the Web of Science database.
Vasilyeva said the project had become the most expensive in the field of Russian higher education for the past several years. For five years of the programme, the amount of state support provided to participating universities amounted to more than RUB50 billion (US$873 million).
For the remaining two years of the programme, an additional RUB29.2 billion will be allocated.
Vasilyeva indicated that the six universities she wants to continue to receive state support as part of the 5-100 programme are National Research University Higher School of Economics; the Moscow Institute of Physics and Technology; the Novosibirsk State University; St Petersburg National Research University of Information Technologies, Mechanics and Optics; National Research Nuclear University and the National University of Science and Technology.
Rectors critical
Representatives of the Russian scientific and university community have criticised the proposal.
Andrei Klemeshev, rector of the Immanuel Kant Baltic Federal University, which is one of the universities participating in the second wave of the project, from 2015, said the dropping of most universities from the programme would lead to serious reputational losses for the entire Russian system of higher education.
The same position is shared by Yaroslav Kuzminov, head of the Higher School of Economics, who said: "Universities participating in the 5-100 project receive state funds to solve economic problems of Russia, not their own. There is a need to continue implementation of the project in its original form.
"Global competitiveness in the international arena is ensured by a group of several dozen universities; however their limitation to six is simply impossible because of the size of our country."
According to Russia Indicator, Kuzminov, supported the Deputy Prime Minister's view that Russian universities are moving quickly up the rankings and more than six institutions had a chance of making it into the top 100.
"If we look at the quality of the promotion of Russian universities and, for example, Chinese universities at the stage that corresponded to the first three years of the first Chinese project, we will see that Russian universities are growing about twice as fast in the ratings," he said.
According to a report in Russia Vedomosti, Isak Frumin, the scientific director of the Higher School Education Development Institute, said: "The letter of the decree is five universities in the first hundred, but the spirit is the increase of the global competitiveness of the higher education system."
He said to achieve five universities in the top 100, you need to have 10 in the top 200 and 20 more in the top 300.
He said similar programmes are under way in 16 countries, taking this approach. In China, nine universities are given significant resources, followed by a group of 30 universities that are given a little less and so on. He told Russia Vedomosti that Chinese or German universities taking part in similar programmes are allotted two or three times as much funding per student.
Ranking positions
In this year's QS World University Rankings published in June, Russian universities maintained the progress they recorded last year with Lomonosov Moscow State University re-entering the top 100 after an absence of several years. Russia's top five universities (one in the top 100, two in the top 300 and two in the top 400) all rose more than 10 places, and 14 of the 24 ranked institutions were up on last year.
In the THE World University Rankings, published in September, Lomonosov Moscow State University was ranked 195th, down from equal 188th last year. Russia also had one university in the top 300, two in the top 400, and four in the top 500.
In the 2017 Academic Ranking of World Universities or ARWU released in August, Russia had one university in the top 100, Lomonosov Moscow State University (93rd), plus Saint Petersburg State University (301-400) and Novosibirsk State University (401-500) in the top 500.
Copyright University World News 2007-2014.
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University World News / 20 October 2017
Threat to cull elite Project 5-100 universities blocked
- Brendan O'Malley and Eugene Vorotnikov
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В ближайшее время количество участников Проекта 5-100 сокращаться не будет, однако ситуация может измениться после президентских выборов в марте 2018 года.
The Deputy Prime Minister of the Russian Federation, Olga Golodets, has ruled out any imminent adoption of a proposal by the Minister of Education and Science, Olga Vasilyeva, to remove funding from 15 out of 21 institutions in the Project 5-100 elite universities programme to concentrate on six institutions.
A spokesperson for the Deputy Prime Minister's Office told University World News that for the time being the programme will remain unchanged, but that could change after the presidential elections in Russia in March 2018 and in the case of a budget deficit in 2018.
Golodets, who is also chairperson of the Project 5-100 Council, issued a statement on Thursday, saying: "All of the 21 universities participating in the programme will continue to be participants. The formula presupposes that all of the universities will be funded."
"And soon, on the 27-28 of October, the members of the international council, which will evaluate the progress of each of the universities, will meet. We have noticeable positive change, and I think that they will be duly recognised and appreciated."
As reported by University World News, Vasilyeva had told a 4 October meeting of university rectors from institutions participating in the project that the remaining RUB30 billion (US$521 million) in funds for the programme should be concentrated on six institutions in order to improve the chances of it securing its objectives by 2020.
She said: "These higher education institutions should enter the world top-100 universities, in accordance with the order of Russia's President Vladimir Putin [issued in] May 2012."
The deputy prime minister repeatedly tried to stop Vasilyeva from discussing the matter at the meeting. But after she left the meeting, Vasilyeva told rectors there was no alternative if the president's objectives were to be met.
However, Vasilyeva appears to have overstepped her authority, as the Ministry of Education and Science cannot make such a decision on its own. The 5-100 initiative is under the direct governance of the Cabinet of Ministers of the Russian Federation, which has power over the Ministry of Education and Science.
In an email exchange with University World News on Thursday, Andrei Volkov, deputy chairman of the Project 5-100 Council, said: "In order to change the design of the project, for example by cutting the number of universities, there should be a consensus between the Ministry of Education and Science, the Cabinet of Ministers, and the Presidential Administration of the Russian Federation. As of now, there is no unanimity in this particular matter."
Vassilyeva's proposal created dismay among the university leaders who were highly critical of her narrow interpretation of the mission of the project, believing that global competitiveness requires supporting a broader base than just six institutions in a country of Russia's size.
Volkov told University World News that the minister's proposal, if for any reason it did go through, would have negative effects on the whole system of higher education, as it would "undermine confidence in the sustainability of political decisions".
He said the project's influence is strong and goes well beyond the 21 institutions involved, encouraging universities which are members to change their models and strategies and this "inspires other universities".
"Cutting the number of participants will send a strong negative message, but the most innovative and forward-thinking universities - some of them are among the six suggested by the Minister Vasilyeva, others are not - will continue to develop and grow. It is the process that cannot be stopped."
Previously, as reported in Russia's Vedomosti, Isak Frumin, the scientific director of the Education Development Institute at the National Research University Higher School of Economics, said: "The letter of the decree is five universities in the first hundred, but the spirit is the increase of the global competitiveness of the higher education system."
He said to achieve five universities in the top 100, you need to have 10 in the top 200 and 20 more in the top 300.
According to a report in Russia Indicator, Yaroslav Kuzminov, head of the Higher School of Economics, supported the deputy prime minister's view that Russian universities are moving quickly up the rankings and more than six institutions had a chance of making it into the top 100.
"If we look at the quality of the promotion of Russian universities and, for example, Chinese universities at the stage that corresponded to the first three years of the first Chinese project, we will see that Russian universities are growing about twice as fast in the ratings," he said.
Copyright University World News 2007-2014.
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University World News / 21 October 2017
How many excellent universities does Russia need?
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В свете недавней дискуссии о том, сколько участников должно остаться в Проекте 5-100, автор статьи размышляет, сколько вообще университетов мирового класса есть в России, а самое главное - сколько их должно быть?
At a recent meeting of the Association of 5-100 Universities, a discussion arose about how many universities should remain in the 5-100 Academic Excellence Initiative. Currently 21 universities are in the project.
The discussion points at deeper questions: how many world-class universities does Russia have, and, more importantly, how many should we have? At the moment, we see only one objective measure - international rankings. Of course, they should not be turned into the ultimate icon of universities' success. The rankings, for example, do a good job measuring the contribution to research potential, but, at the moment, a poor job of measuring the contribution to economic and social development.
If we look at, for example, the Times Higher Education World University Rankings, we see the following picture: there are two Russian universities in the top 300, and none in the top 100.
Historically, our universities have been highly specialised. It is very difficult for them to advance in general institutional rankings quickly. However, if you were to look more closely at subject areas, we have a lot to be proud of. A number of Russian universities are already in high positions, and another five to 10 will join the elite group if they keep moving with the same speed and are given space to think, resources, and time.
What has the Project 5-100 achieved?
When the project was developed in 2012, the Decree of the President formulated the task of bringing five universities to the top 100 by 2020. The task is the right one in terms of ambition, but, due to many factors, including international reputational inertia, hardly achievable. The idea of world-class universities as organisations with global influence has taken hold in politics, but it took China 22 years to get two universities in the top 100, South Korea 18 years for two universities, and Germany 11 years for 10 universities.
Should a more humble task have been set instead? No. The task must be ambitious, complex and challenging - a moonshot project if you like. It shook the system of Russian higher education and forced the universities to look at themselves in the global glass, assess their level and formulate new measurable goals and objectives. This dynamic by itself is much more important than the place in the rankings.
How are the results of universities' progress in the programme evaluated? The score is three-dimensional. The first dimension is the world universities rankings. The second is 10 indicators from the Ministry of Education and Science of the Russian Federation. And, finally, the third dimension is the conclusions of the members of the international 5-100 Council, which assesses the target models and strategies.
The dynamics of the universities from Project 5-100 in the rankings is unprecedented, taking into account that only four years have passed since the launch of the project. Universities' results in terms of the indicators from the ministry are also good: volume of research and development, publication activity and selectivity.
Like everywhere, the temptation to evaluate the development of the universities solely on the basis of objective data that is easy to measure is great. But participating universities have different starting positions, disciplinary profiles, regional contexts, ideas and opportunities. Therefore, in addition to quantitative evaluation, the procedure of evaluations by the council is used.
The 5-100 Council is quite unusual for national academic excellence initiatives, as it includes, in addition to six members from Russia, six more representatives of China, Hong Kong, Great Britain, Belgium and the United States, who bring in experience from both dynamically changing and stable university systems.
But all of this is the public face of the programme. Changes within the universities are much more interesting and significant.
What is happening? New research and development areas, responding to the challenges of the 'third industrial revolution' are being introduced - namely, biomedicine, programmable matter, neural networks and artificial intelligence. Social sciences and humanities are being reintroduced into the list of disciplinary priorities.
In addition, the educational process is moving from standardised to individualised.
More importantly, the university community has started to raise challenging questions about the opportunities of universities and their societal role. A new generation of rectors has come, and they see the development prospects in a new way - letting go of the old way of expecting standards and regulations from the ministry, the universities have started to determine their own direction.
Being deeply involved with the development of 5-100 universities, I can note a tense, emotionally charged atmosphere of real meaningful competition. The universities, as before, closely follow each other. However, now they envy not only the status but also models of operation of other universities, and they worry that their students will switch to another university, because it is more interesting there, and not merely because it is more 'prestigious'.
The impact of Project 5-100 is much broader than 21 universities. About a hundred higher education institutions are observing the 5-100 group very closely and are comparing themselves to the universities of the group. Many of them are thinking about their own transformation for the first time. A few dozen have taken steps on the path laid by the project participants.
We must also remember that the first 18 months to two years were spent on mobilising internal resources. Changes in the universities are only now picking up speed, and the most impressive results are ahead.
Ideology and design of the project
From the start, the 5-100 Initiative was aimed at transformation, not modernisation. Russian universities have to cover the distance their Western counterparts have covered in the past 60-70 years five times as fast to catch up, and then make a breakthrough in order to partake in the global game on equal terms, rather than from, in the view of students, the second echelon, or 'periphery'.
To go beyond what is possible in higher education now, we are critically rethinking the rules of this game and looking for out-of-the-box solutions.
Meanwhile, today the world of innovation in higher education has expanded beyond the West. Innovations are occurring everywhere, in India, China, Indonesia, in South Africa, in the Arab world. But transformational transitions do not occur to national systems in their entirety. The same principle is at work everywhere: selection and concentration. A group of leaders is selected; they receive extra resources and in return promise development.
It is very important that in the beginning of the project we avoided the mistake of choosing just five or six universities and investing all the resources into their growth. We remember the experience of the 1990s - in 1991 a group of leading universities was identified and provided with increased funding unconditionally, which created uncompetitive conditions for the entire sector of higher education.
Just like other organisations, universities can both develop and stagnate all the way down to organisational bankruptcy. It is critically important that the boundaries of the programme of Project 5-100 are passable. A place among 21 participants of 5-100 is not guaranteed forever, and any university in the country has the potential to become a member of the group.
Under the conditions of competitive support, a strong-willed leadership team, and a well thought-out model, any university can surprise you.
For example, in Russia, National Research University of Information Technologies, Mechanics and Optics has suddenly begun actively developing entrepreneurial culture; Moscow Engineering Physics Institute is channelling its nuclear competencies into biomedicine; the University of Tyumen has made astonishingly innovative moves in humanities, social sciences, environmental and agricultural biology; the Far Eastern Federal University is experimenting with new methods of project learning; and Tomsk State University is making bold moves with computer science education.
Every year the participants of the 5-100 Initiative must defend their place. According to the results of a yearly evaluation, the funding is distributed differently - by an order of magnitude - according to progress made. That is, the leading group, the composition of which is unstable and varies depending on universities' success, takes 70% of the programme's funding. This creates a powerful reputational pressure for the leadership of the universities.
Laying foundations
With our geography and history, we will not be able to confine ourselves to a few world-class universities. Using the Times Higher Education top 300 ranking, the United States has 84 universities, the United Kingdom 38, Germany 36, China 7, and Russia, as has already been mentioned, has only 2. However, now is the crucial moment in history when we can lay the foundation for the future network of universities occupying key positions in the global division of intellectual labour.
Despite the recent discussion, which, paradoxically, in the end has proved to be useful for the project, bringing it into the spotlight of public attention, I hope that the programme will continue well into the future and will keep being impactful and beneficial for the whole Russian higher education system.
Andrei Volkov is academic policy advisor of the Moscow School of Management Skolkovo in Russia and deputy chairman of the Project 5-100 Council.
Copyright University World News 2007-2014.
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Ciel FM / 10/16/2017
Le centenaire de la révolution de 1917 en Russie sera le thème franco-russe de la conférence
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16 октября в Париже прошел научный франко-российский форум «Уроки Октября» (Leçons d'Octobre), посвященный столетию революции 1917 года и ее влиянию на судьбу России и мира.
L'impact des événements révolutionnaires de l'automne 1917 sur le destin de la Russie et de la paix sera le thème du forum scientifique, qui s'ouvre lundi dans la capitale de la France. Comme l'a signalé TASS les organisateurs de la conférence de Рaris « Leçons d'Octobre », parmi les membres du chapitre de l'Académie française sont Hélène Carrère d'Encausse, directeur de l'Institut d'histoire russe de l'Académie des sciences de Russie Yuri Petrov, d'autres éminents français et russes, des scientifiques, des écrivains, des artistes.
Selon les organisateurs du forum, les séances plénières examineront les aspects politiques, économiques et culturels de la révolution russe. Les langues de travail de la conférence - français et russe.
Histoire sans coupures
Dans les salles spirituel et culturel Russe du Centre orthodoxe du quai Branly, où se déroule le forum, simultanément l'exposition « l'Histoire sans coupures » а commencée. Elle recrée l'image de la Russie de période révolutionnaire, a reçu la réflexion dans des posters et des affiches de l'époque. Le format de l'exposition permettra un siècle plus tard, étape par étape, de suivre le développement spectaculaire de l'événement. L'auteur du projet - l'écrivain Sergueï Vengerov.
Lundi soir à Paris, dans la Sainte-Trinité à la cathédrale de l'église orthodoxe russe se tiendra un chant de requiem de toutes les victimes dans les années révolutionnaire de la maladie de carré. Le service de l'église présidera l'évêque Nestor de Chersonèse, qui a fusionné les paroisses et les communautés en France et dans plusieurs autres pays de l'Europe Occidentale.
L'essentiel et l'influence de la révolution d'octobre de 1917, les problèmes de la mémoire historique sont également traité dans un cette semaine à Paris, une conférence scientifique à la Haute Ecole des sciences sociales de la France et de l'exposition de rares documents. En effet en partant de la semaine sera la semaine russe à Paris, a déclaré le centre russe spirituel et culturel.
Le sort des compatriotes
Ainsi, une partie importante de conférences et d'expositions sera consacrée au sort de ses compatriotes, pris à la suite des événements de 1917 à l'étranger. Le présentateur de l'histoire du Mouvement Blanc Alexander Jevakhoff évalue l'émigration révolutionnaire en France, plus de 200 mille personnes.
Parmi les expatriés basés certains syndicats de la Société de la mémoire de la garde impériale, Association des cadets russes en France, il existe à l'heure actuelle. Près de la capitale française, à Sainte-Geneviève-des-Bois, a rappelé l'historien, agit commémoratif de recherche et un centre d'archives de l'émigration russe en France. Il a été créé il y a deux ans avec le soutien de la Fédération de Russie, et ses fonds jouissent aujourd'hui d'une grande attention des chercheurs.
« La prochaine tenue dans la capitale française de forums consacrés à l'anniversaire des 100 ans de la révolution de 1917, estime le représentant spécial du président de la Fédération de Russie sur la coopération culturelle internationale, Mikhaïl Chvydkoï, témoigne de la profonde et véritable de l'intérêt public européen à l'un des moments historiques du XXe siècle, ainsi qu'а l'histoire et à la culture de la Russie en général ».
© 1999-2017 CIEL FM.
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Economic Times / Oct 18, 2017
Indian, Russian scientists craft gold nanostars to destroy cancer cells
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Ученые из НИТУ «МИСиС» совместно с индийскими коллегами из Института ядерной физики Саха и при поддержке специалистов из Российского онкологического научного центра им. Н.Н.Блохина создали наночастицы из золота в форме звезд, способные избирательно уничтожать раковые клетки. Нанозвезды стабильны, нетоксичны и недороги в производстве, а острые лучи делают их эффективными при фототермальной терапии.
KOLKATA: Scientists from India and Russia have crafted star-shaped gold nanoparticles that can selectively destroy cancer cells. These stable, inexpensive and non-toxic particles will also make it possible to detect cancer at an early stage.
The development was reported by scientists from the National University of Science and Technology MISIS (NUST MISIS), Moscow, and the Saha Institute of Nuclear Physics, Kolkata, recently in the journal Chemical Communications.
"The focus of the research was to formulate a benign nanostructure suitable for medicinal purpose," Dulal Senapati from the Saha Institute of Nuclear Physics and head of the NUST MISIS infrastructure project, told IANS.
Star-shaped nanoparticles appear to be the most efficient in photothermal therapy (PTT) that uses light radiation for the treatment of many medical conditions, including cancer. In this process, nanoparticles embedded within tumours generate heat in response to externally applied laser light. It has been well documented as an independent strategy for highly selective cancer treatment.
Senapati said when a nanoparticle reaches the affected area, the area is blasted with a laser pulse. The nanoparticle absorbs the light and focuses it like a lens, directing it straight to the star's sharp edge. This light is then converted into heat (of about 4,500-5,000 degrees Celsius), which is concentrated at the star's tip. The generated heat flow breaks the membrane of a cancer cell and destroys it while not harming the healthy cells.
"Our star-shaped nanoparticles absorb light at a wavelength of 600-900 nanometers, which is very good because our bodies are more transparent to the radiation in this range. Most biological molecules cannot absorb light in this range."
Senapati said these nano stars, technically dubbed as plasmonic nanoparticles, scatter light vigorously, and hence can be identified easily under dark-field illumination and other sensing techniques.
"Tracking of these nanoparticles is also possible using surface-enhanced Raman microscopy as they often enhance the scattering of light to many folds," he said.
Gold nanoparticles are synthesised in a water solution of vitamin C, which makes them inexpensive and non-toxic. According to preliminary estimates, the net cost of 100 microlitres is about 50 rubles (Rs 56).
"Young scientists from the NUST MISIS Energy Efficiency Center, under the supervision of Professor Dulal Senapati from the Saha Institute of Nuclear Physics, have managed to solve this problem," said NUST MISIS Rector Alevtina Chernikova.
"They have synthesised stable gold nanoparticles that do not aggregate in blood and are highly efficient in Raman spectroscopy."
Experts from the Blokhin Russian Cancer Research Center also participated in the development. Scientists are currently working on improving the particles by creating various types of "stars."
Copyright © 2017 Bennett, Coleman & Co. Ltd. All rights reserved.
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The Japan Times / Oct 19, 2017
Russia's Lake Baikal, the world's deepest, is in peril, scientists warn
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Озеро Байкал переживает самый тяжелый кризис в новейшей истории, а ЮНЕСКО в прошлом месяце отметила, что экосистема озера подверглась сильным изменениям.
Lake Baikal is undergoing its gravest crisis in recent history, experts say, as the government bans the catching of a signature fish that has lived in the world's deepest lake for centuries but is now under threat.
Holding one-fifth of the world's unfrozen fresh water, Baikal in Russia's Siberia is a natural wonder of "exceptional value to evolutionary science" meriting its listing as a World Heritage Site by UNESCO.
Baikal's high biodiversity includes over 3,600 plant and animal species, most of which are endemic to the lake.
Over the past several years, however, the lake, a major international tourist attraction, has been crippled by a series of detrimental phenomena, some of which remain a mystery to scientists. They include the disappearance of the omul fish, rapid growth of putrid algae and the death of endemic species of sponges across its vast 3.2 million-hectare (7.9 million-acre) area.
Starting in October, the government introduced a ban on all commercial fishing of omul, a species of the salmon family only found in Baikal, fearing "irreversible consequences for its population," the Russian fisheries agency said.
"The total biomass of omul in Baikal has more than halved since 15 years ago" from 25 million tons to just 10 million, the agency said.
Local fishery biologist Anatoly Mamontov said the decrease is likely caused by uncontrollable fish poaching, with extra pressure coming from the climate.
"Baikal water stock is tied to climate," he said. "Now there is a drought, rivers grow shallow, there are less nutrients. Baikal's surface heats up and omul does not like warm water."
UNESCO last month "noted with concern that the ecosystem of the lake is reported to be under significant stress" and a decrease in fish stocks is just one observable effect. The Baikal omul, a well-known specialty, was for centuries the main local source of food, eaten salted or smoked, and especially important given the region has no farming. Another peril to the lake's ecosystem is the explosion of algal blooms unnatural to Baikal with thick mats of rotting Spirogyra algae blanketing pristine sandy beaches, which some scientists say indicates that the lake can no longer absorb human pollution without consequence.
"I am 150 percent sure that the reason is the wastewater runoff" from towns without proper sewage treatment, particularly of phosphate-containing detergents, said Oleg Timoshkin, biologist at the Russian Academy of Sciences' Limnological Institute in Irkutsk.
Fifteen years ago, some of the lake's picturesque villages had only two hours of electricity a day, but now improved power access means that "every babushka rents out rooms and has a washing machine," he said.
Indeed the lake, which is 1,700 meters (5,580 feet) deep, and its tourism now provide a livelihood for many residents to replace fishing.
Foreign visitors often spend time at Baikal while doing a trip on the Trans-Siberian Railway and in recent years more Chinese have been coming as Russia eased visa requirements. Russians love the area, too, for its hiking trails, camping and spectacular scenery.
Timoshkin has traveled the length of Baikal testing for Spirogyra prevalence and said that in three critical zones near populated areas "the bottom does not look like Baikal anymore" and algae is pushing out oxygen-loving molluscs and crustaceans.
Near the town of Listvyanka, the tourist hub closest to regional centre Irkutsk, "there used to be underwater forests of sponges 15 years ago, now they are all dead," Timoshkin said. Last year, Timoshkin tested 170 types of sponges throughout Baikal's coast, and "only 11 percent looked healthy," he said. "When you take a dead sponge to the surface it smells like a corpse."
If dumping polluted water into the lake doesn't stop, "shallow coastal zones will change severely," he said, calling for a ban on phosphate-containing substances in the region and building "the best sewage treatment plants in Russia."
President Vladimir Putin in August complained of "extremely high pollution" while visiting Lake Baikal, calling its preservation a "government priority."
A special 1999 law in Russia spells out protection measures for Lake Baikal. The government is also putting 26 billion rubles (about $452 million) into a cleanup program, which started in 2012, to fund treatment facilities, though local experts say much of the money gets wasted.
In one town, Babushkin, on Baikal's shore, millions of dollars were spent on a brand new treatment plant but bacteria meant to purify the water fail to work in the Siberian winter, local media said.
"As usual, the strictness of our laws is compensated by the fact that following them is optional," said Buryatia-based ecologist Sergei Shapkhayev. "Money is being allocated but it gets stolen."
Science funding has also grown thin at a time when studying Baikal is most vital, both Timoshkin and Mamontov said. "How can you cut funding during a crisis?" Timoshkin asked.
"That's like firing epidemiologists during a smallpox outbreak."
The Japan Times Ltd. All Rights Reserved.
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EurekAlert / 25-Oct-2017
Alvarezsaurid dinosaur from the late Cretaceous found in Uzbekistan Several distinctive bones identify this rare theropod.
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Ученые из Зоологического института РАН и Национального музея естественной истории (США) изучили останки найденного в Узбекистане пернатого динозавра - представителя семейства альваресзавридов. В происхождении и эволюции этих пресмыкающихся, изначально считавшихся ранними птицами, до сих пор много неясного.
Bones from an Alvarezsaurid dinosaur were discovered in Uzbekistan and could shed light on the evolution and origin of the species, according to a study published October 25, 2017 in the open-access journal PLOS ONE by Alexander Averianov of Zoological Institute of the Russian Academy of Sciences, Russia and Hans-Dieter Sues of the Smithsonian Institution, USA.
Previous studies have described Alvarezsauridae as small, long-legged, bipedal dinosaurs with short forelimbs that featured bird-like hands. Since Alvarezsaurid remains are extremely rare, there is plenty to learn about the evolution of this species.
The authors of this study analyzed previously excavated Alvarezsaurid remains from the Turonian Bissekty Formation of Uzbekistan. They examined the vertebrae, the bird-like bone that fuses the wrist and knuckle known as the carpometacarpus, and pieces of what would be the fingers or toes, known as the phalanx. They then measured and compared the shapes and sizes of these bones with those from similar species from the literature.
The authors state that the characteristics for the Alvarezsaurid bones are so distinctive that it could be identified just from the seven bones collected at the Bissekty Formation. These distinctive features included rounded vertebrae located close to the tail, a large and depressed second metacarpal, and a robust second digit with a claw-like end.
While there are competing theories about where the Alvarezsaurid originated, the authors suggest that the discovery of an Alvarezsaurid at this site in Uzbekistan indicates that this group had an evolutionary history in Asia and provides evidence that this continent could have been where the clade originated.
Lead author Hans Sues says: "Our paper reports the discovery of the earliest known alvarezsaurid dinosaur from the Northern Hemisphere, based on 90-million-year-old fossils from Central Asia. Alvarezsaurids were unusual small predatory dinosaurs that had very short but powerfuly built arms that ended in a single large digit."
Copyright © 2017 by the American Association for the Advancement of Science (AAAS).
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Phys.Org / October 27, 2017
Russian scientists find flaws in popular theories of gravity
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Исследовав поведение моделей Хорндески (наиболее общий возможный класс теорий гравитации) в астрофизическом масштабе (на примере черных дыр), физики из Уральского федерального университета и Токийского университета пришли к выводу, что теория гравитации, вроде бы прекрасно работающая на космологическом уровне, слабо применима к реальному миру.
Using a model of black holes, scientists from the Ural Federal university (UrFU, Yekaterinburg) determined that a popular theory of gravity that seemed to work perfectly at the cosmological level (a subclass of Horndeski theory) does not apply in the real world. They have published their results in Classical and Quantum Gravity.
Modern physics has accumulated a lot of prerequisites for the revision of general relativity, including the accelerated expansion of the universe, the presence of dark matter, and the impossibility of renormalizing gravity. All the fundamental interactions known to science have been described in quantum language except for gravitation. These small inconsistencies indicate that the theory of relativity is not the final theory of gravitation, but an approximation (a similar story occurred with Newton's theory). Theoretical physicists constantly propose extended theories of gravity, and these models need to be compared with observations.
One of the simplest versions of such an extended theory appears under the assumption that the gravitational constant (a fundamental physical quantity that is the same in time and at all points in the universe) is not a constant, but a field that can vary in time and space. Scientists cannot measure this slowly changing field with accuracy, and only therefore perceive it as a constant. This theory posits gravity with a scalar field (given only one number at each point). This is how the first and simplest theory of gravity with a scalar field, the Brans-Dicke theory, was formulated. This and similar theories are considered to be among the most promising ways of expanding General Relativity.
In her work, Daria Tretyakova, PhD from UrFU, together with her colleague from the University of Tokyo, explored one of these theories - the so-called Horndeski theory. The Horndeski framework gives the most general theory of gravity with a scalar field, without instabilities, and containing "healthy" physics - that is, without any unusual parameters of matter, for example, negative or imaginary mass.
At the cosmological level, a subclass of Horndeski models, which are symmetric with respect to the shift of the scalar field in space and time, have helped scientists describe the accelerated expansion of the universe without resorting to additional theories. These models were chosen for rigorous and comprehensive testing. The authors of the paper considered the Horndeski models at the astrophysical scale - the scale of individual objects of the universe - and determined that black holes (as real objects) turn out to be unstable in the models which previously successfully proved themselves in cosmology.
Consequently, these models are not suitable for describing the real universe, because black holes are currently believed to exist in space as stable objects. However, the scientists have proposed a way to construct Horndeski models that ensure black holes stability. The paper is a step toward a new theory of gravity that fulfills the requirements of modern physics. Now, the authors are planning to subject the newly proposed models to standard tests to check their adequacy at the cosmological and astrophysical scale.
© Phys.org 2003-2017, Science X network.
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EurekAlert / 27-Oct-2017
From Cellulose to 3-D Objects 3-D printing with a biobased polymer for CO2-neutral manufacturing.
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Исследователи из Института органической химии им. Н.Д.Зелинского РАН разработали новый полимер для трехмерной печати, полностью изготовленный из биомассы. Изделия из него имеют высокое качество, легко перерабатываются, хорошо выдерживают действие растворителей.
In our modern world, eliminating plastics is inconceivable. Unfortunately, they do have disadvantages, including the formation of CO(2) in both production and combustion, depletion of fossil feedstocks, and growth of landfills. In the journal Angewandte Chemie, Russian researchers introduce a new way forward, a polymer made entirely from biomass that can easily and inexpensively be used in 3D printing. Objects produced in this way are of high quality, easily recyclable, and highly solvent-resistant.
Conventional "subtractive" processes involve cutting, sawing, turning, or milling, which results in a great deal of wasted material. In contrast, 3D printing processes are, in principle, waste-free, because they are "additive": three-dimensional objects are produced in a layer-by-layer application of material. The most common technique is called fused deposition modeling (FDM). In this process, the raw material is squirted through a hot nozzle onto a mobile base and thereby liquefied (extrusion). The printer head produces the programmed form like in a conventional two-dimensional printing process, releasing small amounts of the polymer instead of ink. This is repeated for layer after layer until the desired three-dimensional object is complete. Yet, the polymers used until now have a number of disadvantages that limit their use. Some of the polymers are attacked by organic solvents. Those that withstand the solvents, on the other hand, adhere poorly and shrink on heating, allowing their layers to come apart and causing errors in the printing process.
Researchers working with Valentine P. Ananikov at the Russian Academy of Sciences (Moscow) have now solved these problems while also developing a sustainable process: 3D printing with polyethylene-2,5-furandicarboxylate (PEF), a polymer they make from cellulose.
The team was able to use a commercially available 3D printer under standard settings to successfully make objects. The individual layers of the printed objects were firmly bound to each other and the surface was smooth and of high quality. Tests demonstrated that the objects were resistant to dichloromethane, one of the most aggressive solvents. Thanks to the high thermal stability of the PEF, the printed objects could be repeatedly melted, made into filaments, and printed again.
Computer calculations indicate that the individual building blocks of PEF may contain non-linear fragments and form a spiral twist, which gives an access to new types of geometry. Another important feature is a greater polarity of PEF. The researchers believe that structural diversity opens new superior applications of PEF.
Copyright © 2017 by the American Association for the Advancement of Science (AAAS).
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