|Российская наука и мир|
(по материалам зарубежной электронной прессы)
Mirage News / February 1, 2021
More than 500 species of marine macrofauna can expand Russian fish
Российские ученые провели масштабный анализ макрофауны Чукотского, Берингова, Охотского и Японского морей и северной части Тихого океана и составили список, в который вошли более 1500 видов. По мнению экспертов, 33% - около 500 видов - неосвоенные ресурсы, добыча которых может оказаться выгодной, особенно для экспорта.
Russian scientists have carried out a large-scale analysis of the macrofauna of the Chukchi, Bering, Okhotsk, and Japan seas and the North Pacific Ocean and compiled a list of more than 1,500 species based on the results. According to the experts, 33% of these species are potentially commercial in Russia. Their production could not only diversify the Russian market but also significantly enhance the export potential of the Russian Federation. The research is published in the highly ranked journal (Q1) Environmental Reviews.
"To assess the trawl macrofauna of two Far Eastern and one Arctic sea, and the northern part of the Pacific Ocean, data on the composition of trawl catches of the Pacific Branch of the Russian Federal Research Institute of Fisheries and Oceanography (VNIRO) were used", says Aleksey Orlov, one of the authors of the article, a staff member of the Institute of Oceanology of the Russian Academy of Sciences, VNIRO, and the TSU Biological Institute. "459 scientific surveys of research vessels (at depths from 5 m to 2,200 m) were analyzed for 1977 to 2014. The study area was over 25 million km². The checklist includes 1,541 species, with information on the output and commercial value indicated for each".
A revision of the macrofauna showed that almost 20% of the species in the trawl catches had no commercial value, and about 50% were cheap. Only 3.3% of the species are expensive and the number of catches increases from north to south. About 500 species are unexploited resources, mainly small fish and invertebrates: bivalves and gastropods, sea worms, ascidians, jellyfish, and others. Their total biomass is many times greater than the biomass of the biological resources currently used.
"Currently, the industry is not showing interest in these types for a number of reasons", says Alexey Orlov. "One of the main factors is their nontraditional nature for the domestic market. For example, stingrays, sharks, sea worms, praying mantises, ascidians, jellyfish, and other exotic marine fauna for us are in high demand in Asian markets, especially in China. It is unlikely that they will ever appear on Russian shelves, but it may be quite profitable to extract them for export to Japan, China, Korea, and other countries in East Asia".
Another factor is that small amounts of catch discourage large companies, but such fishing can be profitable for small organizations and will contribute to the development of small and medium-sized private businesses in the fishing industry.
"Another important reason limiting fishing is the lack of information about the availability of free, undeveloped resources, their technological properties, methods of extraction, market value, and sales markets", continues the scientist. "This is exactly the task of fishery science - to identify unused aquatic biological resources and convey the necessary information to fishermen in the form of practical recommendations. This is the main idea of our article".
It should be noted that the published list can be used not only for the effective management of biological resources but also for assessing the environmental damage caused by anthropogenic impact, including pollution in the process of hydrocarbon production, nuclear reactor accidents, poaching, and others.
© Mirage.News 2020.
* * *
The New York Times / Feb. 2, 2021
Russia’s Vaccine Is Safe and Effective, Published Study Shows
A peer-reviewed article in The Lancet shows the vaccine has an impressive 91.6 percent efficacy rate against the virus and is completely protective against severe cases of Covid-19.
В авторитетном британском медицинском журнале The Lancet опубликованы результаты последней стадии испытаний российской вакцины «Cпутник V». Согласно представленным данным, эффективность вакцины составляет 91,6%, серьезные побочные эффекты не отмечены.
Russia cleared a hurdle in its vaccine rollout on Monday with the publication in the respected British medical journal The Lancet of late-stage trial results showing that the country’s Sputnik V vaccine is safe and highly effective.
The publication is sure to buoy the Russian government’s promotion of the vaccine at home and around the world, strengthening the Kremlin’s hand in vaccine diplomacy with a credible endorsement of the product’s safety. Russia drew criticism from Western experts when it approved the vaccine for emergency use in August - before late-stage trials had even begun - and started vaccinations that month. Moscow claimed victory in the vaccine race, as it had decades earlier in the space race with the launch of the Sputnik satellite, though at the time other vaccines were further along in testing. In the end, its politicized rollout only served to deepen skepticism.
The peer-reviewed article published Tuesday cleared those doubts. It showed the vaccine had an impressive efficacy rate of 91.6 percent against the virus and was completely protective against severe forms of Covid-19.
"The development of the Sputnik V vaccine has been criticized for unseemly haste, corner cutting, and an absence of transparency," two independent researchers, Ian Jones of the University of Reading and Polly Roy with the London School of Hygiene and Tropical Medicine, wrote in a commentary published in The Lancet.
"But the outcome reported here," they continued, "is clear and the scientific principle of vaccination is demonstrated."
Their commentary did note that the design of the Russian vaccine, which relies on a genetically modified cold virus and is similar to half a dozen others including those made by Johnson & Johnson and AstraZeneca, is difficult to mass produce. Though quick out of the gate with regulatory approval, Russia has lagged in mass production and actual vaccinations, the process that in fact protects people from illness and death.
The Russian financial company promoting the vaccine has said about two million people have been inoculated with Sputnik V worldwide, far fewer than with the Pfizer or Moderna vaccines. The company, the Russian Direct Investment Fund, does not break down the vaccinations by country. But of the two million vaccinations, at least hundreds of thousands have been in countries outside of Russia, suggesting the government has quietly prioritized exports. While beneficial for speeding global immunity to the disease, the policy has also reaped public relations and diplomatic benefits for the Russian government, even as residents of many provincial Russian cities still do not have access to shots. On Monday, for example, the authorities in the Leningrad region in northwest Russia said supplies had run out. So far, 15 other countries, including Argentina, Hungary and Serbia, have approved the Sputnik V vaccine for emergency use.
"Publication in The Lancet today really shows that Sputnik V is the vaccine for all mankind," Kirill Dmitriev, the director of the Russian Direct Investment Fund, said in a statement. "Today is a great victory."
The vaccine is one of three that have completed late-stage trials showing an efficacy rate above 90 percent, along with the shots made by Pfizer and Moderna. The version of the Russian vaccine tested in the trials must be shipped and stored at difficult-to-manage temperatures below about zero degrees Fahrenheit. The Russian ministry of health has also approved a freeze-dried version that can be stored in a refrigerator. Russia is marketing Sputnik V at a price of about $10 per dose for the two-shot vaccine. The clinical trial conducted in Moscow late last year on about 20,000 volunteers showed only side effects commonly associated with vaccines, such as headaches or mild fevers.
The researchers determined that no so-called adverse events, or serious medical problems among the trial participants, were associated with the vaccine. In total, they found 70 serious medical episodes in 68 people in the trial, in both the placebo and vaccine group. Notably, two people who were administered the vaccine died of Covid-19 following illnesses that began days after the first injection. The researchers said both people were likely infected before the trial began and fell ill before the vaccine had time to generate antibodies to the coronavirus. The "disease had progressed before any immunity from the vaccine developed," they wrote.
The Russian authors of The Lancet article also noted the trial in Moscow lacked ethnic diversity to ensure the vaccine is safe in nonwhite recipients. A trial of Sputnik V underway now in the United Arab Emirates includes a more diverse study group, the researchers say.
© 2021 The New York Times Company.
* * *
Phys.Org / February 2, 2021
"Genetic SD-card": Scientists obtain new methods to improve the genome editing system
Ученые Санкт-Петербургского политехнического университета Петра Великого совместно с бельгийскими коллегами улучшили технологию редактирования генома, разработав полимерные капсулы-носители для доставки к органам и тканям генетического материала. Капсулы универсальны, что позволяет одновременно загружать в них генетический материал разного размера и структуры, чтобы устранять «поломки» в ДНК и лечить пациентов.
Researchers from Peter the Great St.Petersburg Polytechnic University (SPbPU) in collaboration with colleagues from Belgium take a step in the development of genome editing technology. Currently it is possible to deliver genetic material of different sizes and structures to organs and tissues. This is the key to eliminating DNA defects and treating more patients. The project is guided by Professor Gleb Sukhorukov and supported by the Russian Science Foundation. Research results were published in Particle & Particle Systems Characterization journal.
An international research group developed a polymer carrier with a number of unique properties, several types of genetic material can be loaded in its structure. In particular, the scientists managed to load genetic material of various sizes and structures into 'universal containers'. From small interfering RNAs (siRNAs) to messenger RNAs (mRNAs). The efficiency of delivery was demonstrated on human stem cells.
"Nowadays most of the vaccines, including those for COVID-19, are made on the basis of mRNA. This is a kind of 'genetic SD-card' with information which activates the human immune system, thus teaching it how to deal with the 'enemy proteins' of the virus. Typically, for medical purposes, different types of carriers are used to deliver specific molecules; we proved that it is possible to deliver genetic materials of different sizes using one type of carrier. This technology opens up new horizons for the development of non-viral delivery systems," notes Alexander Timin, head of the Laboratory for microencapsulation and controlled delivery of biologically active compounds at St. Petersburg Polytechnic University.
Scientists added that the micron-scaled carrier with incorporated genetic material can be delivered by systemic administration, or locally (directly into the tumor focus for cancer).
"The study is conducted jointly with the Raisa Gorbacheva Memorial Research Institute of Children Oncology, Hematology and Transplantation, which provided the patients' mesenchymal stem cells (cells building organs and tissues) for the experiments. In the future, we plan to conduct experiments on tumor-bearing laboratory animals in order to find out how the genetic material delivered to the tumor will be managed," said Igor Radchenko, director of the "RASA-Polytech" center.
© Phys.org 2003-2021 powered by Science X Network.
* * *
HeritageDaily / February 3, 2021
Archaeologists Excavate Anthropomorphic Stele at Roman Necropolis
Экспедиция Института археологии РАН обнаружила в некрополе Киль-Дере 1 (Инкерманская долина, Крым) более 60 надгробий с захоронений скифской знати времен Римской империи (I-IV вв. н. э.): антропоморфные стелы, надгробные стелы с личинами, основания для стел. На данный момент это самая крупная коллекция надгробий с раскопок позднескифских могильников Крыма.
Archaeologists from the Institute of Archaeology at the Russian Academy of Science have discovered a Roman necropolis in the Crimea, containing anthropomorphic gravestones and stele.
During the Roman period, the Crimea (called Taurica) was part of the Bosporan Kingdom, a suzerainty state submissive to Roman rule. It was briefly incorporated as part of the Roman province of Moesia Inferior from 63 to 68 AD, before being restored as a Roman client kingdom.
The discovery was made during excavations of the Kil-Dere 1 burial site, in preparation for a new highway near the town of Inkerman 5 kilometres east of Sevastopol.
Kil-Dere 1 and associated burial sites nearby, probably relate to the ancient city of Tauric Chersonesos on the shore of the Black Sea, first founded by settlers from Heraclea Pontica in Bithynia in the 6th century BC.
Unfortunately, the team found that the necropolis had already been targeted by illegal excavations and treasure hunters, with over 120 shafts and pits being excavated with modern digging equipment. Of the 232 burials studied by the team, only 14 remained intact with no evidence of disturbance.
In the course of documenting the wider site, the team discovered 63 tombstones of varying types, consisting of anthropomorphic stele, grave stele depicting masks, and the bases for steles.
The Institute of Archaeology RAS said in a press statement: "It is the most significant collection of tombstones ever obtained during the excavation of the Late Scythian burial grounds of the Crimea of the Roman period: only 15 such tombstones have been found in the nearest large and well-known necropolises."
Archaeologists have also discovered more than 1200 grave goods at Kil-Dere 1, consisting of small decorative objects with precious metals, to ceramic red-lacquered plates, jugs and bowls.
An Institute of Archaeology RAS spokesperson stated that the grave goods allow archaeologists to build a chronology of the ethnic population inhabiting the region, suggesting that Kil-Dere 1 was active as a burial site from the 1st - 2nd century, until the 4th century AD.
© 2020 - HeritageDaily.
* * *
India Education Diary / February 3, 2021
ITMO: Scientists Receive Award from Academia Europaea’s Russian Club
Сотрудники ИТМО Максим Горлач и Валентин Миличко стали лауреатами премии Европейской Академии, неправительственной организации, объединяющей ведущих ученых всех европейских стран. Премии вручаются раз в несколько лет за выдающиеся достижения в физике, химии, науках о Земле, биологии, медицине и гуманитарных науках. Максим Горлач получил награду за исследования топологических состояний света, а Валентин Миличко - за исследования взаимодействия света и материалов со сложной внутренней структурой.
Academia Europaea, which has counted 76 Nobel Prize laureates as its members, is sometimes described as the "European Nobel Laureates’ Club". This organization unites leading scientists from Europe and Russia. The Academy’s prizes are awarded once every several years for remarkable achievements in one of the six fields of study: physics, chemistry, Earth sciences, biology, medicine, and the humanities. The nominees are selected by the Russian branch of the Academy and reviewed by the European committee.
This year, two employees of ITMO University’s Faculty of Physics and Engineering were among the winners. Maxim Gorlach received an award for his studies of the topological states of light and Valentin Milichko - for research into the interaction between light and materials with complex inner structure.
According to Maxim Gorlach, the prize is awarded not for any specific publications or results, but a series of studies. His application was submitted in 2019; it included a paper on the extraction of topological invariants from the scattered far-field, which was in Nature Communications, as well as an article on the optical realization of quadrupolar topological insulators created in collaboration with American colleagues, which was in Nature Photonics.
Valentin Milichko notes that such an award is an important sign of recognition from the European scientific community.
"Firstly, it’s a pleasure to receive such recognition of your services. For any scientist, it’s important to understand that your work really matters and is highly appreciated by the scientific community. Secondly, it makes your scientific field and your university a bit more popular: such prizes attract the attention of both colleagues and young students from the European Union. Only 15 people from all over the EU and Russia are usually chosen as winners. It’s a tough competition, so it’s quite prestigious to receive this award," he says.
Maxim Gorlach adds that the fact that two scientists from ITMO University are among the winners is proof of the university’s competitive ability - young scientists conduct cutting-edge research here.
Valentin Milichko has also received a as the most-cited young Russian scientist and an. His research interests include the creation and study of hybrid materials’ properties in optics. In particular, one of the relevant tasks is the development of metallic-organic carcasses and complex nanoparticles for light control, as well as for the creation of optical transistors and memory elements.
Maxim Gorlach is from the BASIS Foundation for the Advancement of Theoretical Physics and Mathematics for research of topological states of quantum light and entangled photons. His research activities are connected with research of, which are resistant to defects and disorder.
© Copyright IndiaEducationDiary, 2020.
* * *
Science Codex / February 05, 2021
Ural Federal University scientists developed a new way of synthesis of high-purity zircon
Ученым Уральского федерального университета, Института химии твердого тела УрО РАН и Института геологии и геохимии УрО РАН удалось синтезировать циркон высокой чистоты с определенными спектральными свойствами. Такому циркону можно придавать различные свойства и использовать для решения многих задач.
The scientific novelty of the work of scientists from Ural Federal University, Institute of Solid State Chemistry and Geology and Geochemistry of the Ural Branch of the Russian Academy of Sciences lies in the fact that for the first time scientists solved the task of creating zircon with certain spectral properties. To this end, they have worked out the so-called sol-gel method.
* * *
It is distinguished by its technological simplicity, controllability of processes and allows synthesizing a larger volume of products with high purity than with other methods.
First, from carbonate of zirconium metal and an organosilicon compound, they obtained a sol - a dispersed medium with the presence of small solid particles, from it - a colloidal system, then, after drying and grinding, a precursor powder of a high degree of homogeneity, which was subjected to further grinding and calcination.
Second, it was found that upon mechanical stirring and sequential annealing - heating to 1550 °C and further cooling the precursor to room temperature - the number of defects in the synthesized sample decreases and its high purity is achieved.
The range of applications of zircon obtained by the scientists from Yekaterinburg is very wide. Due to its high melting point (above 2000 °C), chemical resistance, mechanical strength, low expansion coefficient at high temperatures and low thermal conductivity, zircon is useful as a refractory material (for example, for the manufacture of industrial furnaces) and a pigment for the production of heat-resistant paints. The presence of impurities and defects in the structure allows us to consider it as a standard for studying the mechanisms of defect formation in natural zircon crystals.
"Even a small concentration of impurities, such as iron, manganese, titanium, rare earth elements, significantly affects the luminescent properties of zircon, in some cases, the impurities enhance the glow in a certain range of electromagnetic waves. In other words, with the help of impurities, you can give zircon the necessary luminescent properties and use it as a phosphor or to detect the level of radiation damage, since the structure of zircon well "remembers" the radiation dose that it received," says Dmitry Zamyatin, senior researcher, Research Laboratory "EXTRA TERRA CONSORTIUM", UrFU Institute of Physics and Technology.
Furthermore, the synthetic zircon matrix is able to contain large amounts of uranium and thorium. This allows the synthesized zircon to be used as a container for long-term storage and disposal of radioactive elements.
Marianne / Le 08/02/2021
Méthode, efficacité face aux variants, production : ce que l'on sait du vaccin russe Spoutnik V
Судя по опубликованным в журнале The Lancet результатам третьей стадии испытаний «Спутника V», российская вакцина может войти в тройку самых эффективных, после Pfizer/BioNtech и Moderna, и является «серьезным кандидатом» на участие в широкомасштабной вакцинации. Остается решить проблему производства.
Le 2 février, une étude publiée dans la revue scientifique "The Lancet" soulignait que le vaccin russe Spoutnik V était efficace à 91,6 %, frôlant les chiffres de Moderna et Pfizer/BioNTech. Celui-ci pourrait permettre à l’Europe d’accélérer sa campagne de vaccination, comme l’OMS l’en exhorte.
* * *
Spoutnik 1, c’est le premier satellite artificiel de la Terre, mis en orbite le 4 octobre 1957. Une prouesse scientifique. Sauf qu’il ne servait à rien, à part à émettre "bip-bip" sur certaines fréquences radios. Politiquement pourtant, le message était fort. À l’époque, aux États-Unis, on parle d’un "Pearl Harbor technologique". De quoi permettre aux Soviétiques de gagner la première partie de la course spatiale. Le nom du vaccin produit par l’institut russe Gamaleya est donc chargé de sens. Spoutnik V est-il, lui aussi, une prouesse scientifique ?
Non, mais à l’inverse du satellite dont il hérite du nom, il est utile. Avec une efficacité de 91,6 %, il avoisine le niveau de protection des vaccins de Pfizer/BioNTech et Moderna, et dépasse largement celui du britannique AstraZeneca. Il est donc "un candidat sérieux" à la vaccination à grande échelle d’après Stéphane Paul, immunologiste au CHU de Saint-Etienne et membre du comité scientifique sur les vaccins Covid-19, et "une bonne nouvelle pour l’humanité" selon le chef de la diplomatie de l’Union européenne Josep Borrell. Son homologue russe a souligné sa volonté de coopérer avec ses rivaux occidentaux, ouvrant la voie à une autorisation européenne. Reste pour cela à résoudre la question prioritaire de la production.
Troisième marche du podium de l’efficacité
Depuis le début de son développement, peu de données à l’égard de Spoutnik V ont été communiquées par son concepteur, l’institut Gamaleya. Vladimir Poutine s’est simplement vanté, mi-août, d’avoir vacciné sa fille avec le "premier" vaccin contre le Covid-19, qui permet selon ses dires "de développer une forte immunité" et qui aurait "passé tous les tests nécessaires". En réalité, la troisième et ultime phase des essais cliniques n’était pas terminée. "Cette annonce, même tardive, est donc une très bonne nouvelle", insiste Cécil Czerkinsky, directeur de recherche en immunologie à l’Inserm.
Faut-il s’inquiéter du manque de transparence préalable ? "Ces données sont très solides et transparentes, rien ne permet de douter de leur sérieux", considère Stéphane Paul. En effet, les résultats publiés dans The Lancet ce 2 février ont été validés par des chercheurs indépendants, en l'occurrence britanniques. L’efficacité a été testée à grande échelle lors de la troisième et ultime phase des essais. Sur ce point, le vaccin russe n’a rien à envier à ses concurrents : l’essai a concerné 40 000 volontaires, contre 44 000 pour Pfizer/BioNTech et 30 000 pour Moderna.
Cela le place d’office sur la troisième marche du podium des vaccins les plus efficaces, derrière Pfizer/BioNtech et Moderna. Mais celui-ci présente plusieurs avantages, car il repose sur une autre méthode. Les deux autres sont des vaccins à ARN, alors que celui-ci est un vecteur viral. Cela consiste à prendre un autre virus, rendu inactif. On y insère la protéine Spike du Covid-19, qui lui permet de s’attacher à nos cellules. Ainsi, notre système immunitaire apprend à reconnaître cette protéine, et nous protège d’une future infection par le sars-cov-2. Le seul autre vaccin accepté par l’Union européenne à employer la méthode du vecteur viral est celui développé par AstraZeneca et l’université d’Oxford : il repose sur un adénovirus de chimpanzé.
Mais l’efficacité est incomparable : d'après l’Agence européenne du médicament (EMA), elle oscille entre 60 et 70 % pour le vaccin britannique. Pourquoi une telle différence d’efficacité entre Spoutnik V et AstraZeneca ? C’est le point fort du produit russe : alors que pour ses deux injections, le vaccin du second utilise le même virus inactivé, pour le premier, deux différents sont injectés à trois semaines d’intervalle. "C’est une stratégie performante : cela évite que l’on développe des anticorps contre l’adénovirus, qui le reconnaîtront lors de la seconde injection et la rendront moins efficace", explique l'immunologiste Stéphane Paul. "Il s'agit du seul vaccin à utiliser cette méthode des deux injections différentes, poursuit Cécil Czerkinsky. Ce n’est pas une prouesse, mais c’est très astucieux."
Les avantages des vaccins à adénovirus
Les vaccins à adénovirus présentent certains avantages. Ils peuvent être stockés à des températures acceptables : environ 4 degrés pour Spoutnik, contre -70 pour Pfizer et -20 pour Moderna. Cela permet d’envisager leur utilisation dans des pays n’ayant pas les infrastructures nécessaires de stockage à des températures basses. Son prix est lui aussi compétitif. "Le prix d'une dose de Spoutnik V pour le marché international sera de moins de 10 dollars", a annoncé dans un communiqué séparé le Fonds souverain russe, soit autour de 8 euros. Les vaccins à adénovirus sont en effet moins chers que ceux à ARN : compter environ 2 euros pour une dose d’AstraZeneca, contre une petite quinzaine d'euros pour Pfizer et Moderna.
Pas d’ombre au tableau, alors ? Pas si sûr. Le vaccin Spoutnik V ne peut pas encore apporter de réponses quant à l’efficacité contre les variants. "D’autres sont plus avancés", explique Stéphane Paul. Les laboratoires BioNtech/Pfizer et Moderna assurent que leur produit reste performant contre le variant britannique, mais moins contre le variant sud-africain. "La technologie adénovirus peut aussi être ajustée à d’autres variants, mais ce sera plus long que pour les vaccins à ARN", souligne Cécil Czerkinsky. Enfin, comme tous les autres vaccins, celui-ci ne répond pas à certaines interrogations, notamment la durée de la protection, et l’efficacité quant à la transmission de la maladie.
La question de la production
Toutes ces données permettent d’envisager une autorisation par l’Union européenne. La Russie a lancé des démarches en ce sens le 20 janvier. "Au début, nous n’avions aucune donnée sur les phases précliniques", explique Stéphane Paul, membre du comité vaccin. Rien ne permettait donc de soumettre leur candidat vaccin aux autorités sanitaires européennes il y a quelques mois. "Mais ce n’est plus le cas, on dispose maintenant de toutes les informations, et il y a de plus en plus d’échanges avec l’institut russe", poursuit-il. Plus encore, Cécil Czerkinsky a rejoint le conseil scientifique de l’institut russe Gamaleya en décembre. "La condition était de pouvoir discuter en toute transparence, et cela a été le cas, les étapes ont été menées dans les règles, comme pour tous les autres vaccins", assure le chercheur français. Scientifiquement, rien ne semble donc contredire une homologation européenne. Mais c’est un autre problème qui pourrait freiner : la production en grande quantité.
Si la Russie a la possibilité de produire le vaccin pour ses ressortissants et ceux de pays voisins, pour le proposer en Europe, elle doit se plier à ses normes de production - dont on peut aisément penser qu’elles sont plus drastiques dans l’Union Européenne ou en Amérique du Nord qu’en Russie. "Il semble que la Russie ne dispose pas des capacités de production nécessaires tout en respectant des critères de qualité", concède Stéphane Paul.
Combinaison de vaccins
La Russie sollicite donc l'aide européenne pour obtenir une autorisation sur le vieux continent : produire ce vaccin en Europe permettrait d’accélérer le processus de vérification, surtout si les sites de fabrication ont déjà été homologués par l’Agence européenne du médicament (EMA) pour un autre vaccin. Ainsi, l’institut Gamaleya a d’ores et déjà contacté le laboratoire allemand IDT pour produire son vaccin en Europe. "Et il a aussi lancé un essai clinique en partenariat avec AstraZeneca", explique Cécil Czerkinsky. L’objectif : tester l’efficacité de la combinaison des deux vaccins, avec une première injection de l’un, et une seconde de l’autre. Or l’efficacité de Spoutnik V est supérieure à celle de l'injection britannique. Qu’est-ce que les Russes pourraient donc avoir à y gagner ? Là pourrait bien être l’astuce : en échange, AstraZeneca pourrait offrir ses capacités de production. En faisant produire son vaccin par les réseaux du Britannique, l’institut russe s’assure de respecter les normes européennes, les sites ayant été passés au crible pour le vaccin AstraZeneca.
Alors qu’il est utilisé en Russie, en Argentine, ou encore en Algérie, l’efficacité du vaccin russe lui permet de prétendre à une utilisation mondiale plus large. Le seul obstacle est celui de la production, qui pourrait donc être réglé par un partenariat avec AstraZeneca. Sergueï Lavrov, ministre des affaires étrangères russe, a par ailleurs assuré ce vendredi que dans l’Union européenne, "plusieurs pays sont intéressés à produire le vaccin sur leur territoire".
Chemical & Engineering News / February 10, 2021
Hydrogen chloride found in Mars’s atmosphere
HCl’s behavior tells scientists they still don’t understand martian atmosphere chemistry.
Орбитальный аппарат ExoMars Trace Gas Orbiter (совместный проект Европейского космического агентства и Роскосмоса) впервые обнаружил в атмосфере Марса следы хлороводорода. Источник его появления ученым предстоит выяснить. Основных гипотез пока две: наличие на Марсе вулканической активности и выделение хлора из частиц пыли, поднятой в атмосферу во время бури. В любом случае это открытие свидетельствует о еще неизвестных механизмах взаимодействия поверхности и атмосферы Марса.
The first detection of a halogen-containing gas in Mars’s atmosphere is telling scientists there is still a lot to learn about the planet’s chemistry. Researchers spotted hydrogen chloride during Mars’s dusty seasons, and they say water or volcanic activity may be involved in the molecule’s appearance and disappearance in the atmosphere (Sci. Adv. 2021, DOI: 10.1126/sciadv.abe4386).
The first wheeled Mars rover, NASA’s Sojourner, detected chlorine on the planet’s surface in 1997. Subsequent rovers confirmed chlorine’s presence and found chlorine-containing compounds like perchlorates in the martian soil. HCl exists in Earth’s and Venus’s atmospheres and was predicted to be in Mars’s, but researchers had not yet found it there.
Oleg Korablev of the Space Research Institute of the Russian Academy of Sciences says he and his colleagues were looking for signs of methane in data collected by the European Space Agency’s ExoMars Trace Gas Orbiter when they spotted signatures of HCl. The group confirmed the molecule’s presence with two separate infrared spectrometry instruments on the spacecraft. The instruments recorded different amounts of HCl at different altitudes and times of year, sometimes finding none at all. Korablev says HCl appeared when Mars was closest to the sun, which can create warmer, dustier Martian conditions.
That observation would fit with a hypothesis that the gas originates from chlorine-containing molecules in dust particles, which in turn implicates water in Mars’s chlorine cycle: chlorine on the surface may once have been part of sodium chloride in a long-gone martian ocean. A water-derived oxidant like the hydroxyl radical could liberate chlorine from dust particles blown into the atmosphere, forming HCl.
Other hypotheses for HCl’s formation involve photochemistry or electrochemistry from lightning freeing chlorine from dust in the air. Or chlorine could come from a different source altogether-from minerals released by volcanic eruptions or magma rising close to the surface. The group notes that there is little evidence of seismic activity or other gases like SO2 that scientists would expect to see if Mars had erupting volcanoes, so this explanation seems less likely.
Korablev favors the water-based hypothesis. Dmitry Shaposhnikov, also of the Space Research Institute of the Russian Academy of Sciences but not involved in this research, agrees that the available evidence points that way. He says if confirmed, the finding will fill in scientists’ understanding of Mars’s dust, its atmospheric chemistry, and its water cycle.
It’s not only HCl’s source on Mars that still needs to be sussed out; so does its sink. HCl’s disappearance at the end of Mars’s dusty season "is also quite a puzzling thing," Korablev says. The group suggests water ice on the surface or clouds may capture HCl.
Korablev says the group is now analyzing a second year of data from the orbiter to see if these patterns hold. And he thinks laboratory experiments should help pin down the chemical processes involved in Mars’s chlorine cycle.
Copyright © 2021 American Chemical Society. All Rights Reserved.
* * *
Technology Networks / Feb 10, 2021
Why Aren't Our Brains Overloaded by Visual Stimuli?
Посредством зрения человек получает огромное количество информации, однако способность мозга обрабатывать и сохранять данные имеет свои пределы. Согласно одной из гипотез зрительная система способна «сжимать файлы», чтобы избежать перегрузки, в результате чего объекты не анализируются детально, а делятся на категории по простым общим признакам - например, по размеру.
Российские исследователи из Национального исследовательского университета «Высшая школа экономики» провели эксперимент, в ходе которого доказали, что зрительная система человека способна автоматически (то есть без участия внимания) классифицировать объекты на основе не только простых признаков, но и их сочетания.
Russian researchers from HSE University have studied a hypothesis regarding the capability of the visual system to automatically categorize objects (i.e., without requiring attention span). The results of a simple and beautiful experiment confirmed this assumption. The paper was published in the journal Scientific Reports. The study was supported by a Russian Science Foundation grant.
Humans receive a lot of information from the environment through their vision. Every day, we face a flow of varied visual stimuli. At the same time, information processing requires cognitive resources. Like a computer processor, the human brain has limited capacity in terms of the data it is able to process and save in its memory. One hypothesis states that the visual system somehow 'decreases files' resolution in order to avoid overloading. As a result of such 'compression', instead of a detailed analysis of the observed objects, the visual system categorizes them by simple general attributes, such as size. Later, such 'primary data' can be used for a more thorough analysis.
Researchers sought to answer the following question: is the visual system capable of automatic object categorization (i.e., without attention)? In their study, the researchers tried to determine the conditions in which such automatic categorization would work. They used the visual mismatch negativity (vMMN) component measured by electroencephalography (EEG) as a marker of automatic sensory discrimination. vMMN shows the difference between the brain's reactions to a standard (frequent) or a deviant (rare) stimulus. vMMN demonstrates that the visual system noticed a difference between stimuli and, importantly, that it did so without requiring attention.
'We are very interested and amazed by the human visual system's ability to categorize high numbers of objects. For example, when humans look at an apple tree, they immediately differentiate apples from leaves. This study shows that the process of quick categorization can be performed automatically based on the information on differences between objects', says Vladislav Khvostov, Junior Research Fellow at the HSE Laboratory for Cognitive Research, School of Psychology, one of the paper's authors.
To study the automatic distribution of objects into groups using vMMN, the researchers conducted a simple experiment with a fillertask. Study participants were asked to look at a small asymmetrical cross in the centre of the field and press the button each time the cross changed its orientation. This way, the participants' attention was focused on the position of the cross in the centre of the field. The cross was surrounded by rows of lines of varied lengths and orientation. In each experiment block, the combination of these parameters was different. While the participants' attention was focused on the central figure, the researchers used EEG to record brain activity in response to background visual stimulation. In each block of the experiment, the participants were shown 700 visual stimuli, each of which was presented on the screen for 200 ms followed by 400 ms of empty screen. Most of the stimuli included a fixed combination of lines' length and orientation (for example, long lines were steep, and short ones were flat), but in 10% of cases, the combination of parameters was the opposite.
According to Vladislav Khvostov, the only task for the participants was to press a button when the central cross rotated (third image from the left). In the image above, the central cross size is magnified for illustrational purposes. Together with the cross, the participants observed a background visual stimulation consisting of lines with different lengths and orientations. In most cases (standard stimuli) the combination of length and orientation was the same: long lines were flat, and short ones were steep, but in very rare cases (deviant stimuli, seventh image) this combination changed to the opposite: long lines became steep, while short ones became flat. The participants did not pay attention to the change of stimuli, but analysis of EEG indicators showed that the visual system tracked these changes as well.
The researchers were interested in the brain's reaction to the replacement of a standard stimulus with a deviant one. If the feature had only two peak values (short/long in case of length; vertical/horizontal in case of orientation), it was called 'segmentable'. If the attribute had interim values, it was defined as 'non-segmentable.'
The researchers found considerable visual mismatch negativity in response to a deviant stimulus in cases when either both of the features were segmentable, or only length was. Since on all stimuli inside each block, the distribution of lengths and orientations remained constant, the researchers concluded that categorization was not made by one simple feature. This means that the visual system categorized the lines by their combinations. In their experiment, the researchers thus contradicted the assumption that the visual system categorizes the objects only by simple feature. It can solve a less trivial version of the task and use combinations of features.
© 2021 Technology Networks, all rights reserved.
* * *
Emerging Europe / February 11, 2021
Nobel-laureate to head new Russian lab developing neuromorphic technology
В российском Центре изучения мозга и сознания создается Лаборатория физики программируемых функциональных материалов, которую возглавит нобелевский лауреат Константин Новоселов. Лаборатория будет заниматься разработкой и созданием материалов с заранее заданными свойствами.
Linking human beings and computers will be one of the major tasks of the 21st century. A new lab in Moscow looks set to lead research into what has been called neuromorphic technology.
A new lab dedicated to the creation of smart materials with pre-programmed properties, allowing the development of conceptually new technologies, is set to be created at the Brain and Consciousness Research Centre in Moscow, Russia, under the leadership of the Nobel laureate Konstantin Novoselov.
Novoselov, together with another Russian-born scientist, Andre Geim, both then professors at the University of Manchester, won the 2010 Nobel Prize in Physics for discovering graphene, a two-dimensional crystal only an atom thick that has the potential to transform a range of sectors such as electronics, energy, health and construction.
The new lab, which has received a donation of 500 million rubles (6.7 million US dollars) from the billionaire investor and philanthropist Vladimir Potanin, will employ 20 people.
"Over the last few years, there has been an active development of a new direction in physics and material science - synthesis of nanosized materials with specified properties," says Novoselov.
"Now we are not limited to those that nature has provided us - we can create new ones, with given, sometimes very nontrivial, properties. One of the platforms for obtaining such materials is two-dimensional crystals and heterostructures based on them. In our laboratory we go even further: we develop "smart materials" that can change their structure and properties depending on external parameters."
"One of the popular applications for such ‘smart’ materials is neuromorphic computers, where they can be used as a single neuron. But, in principle, such materials are very well suited for creating an interface with living objects, in particular for studying the brain. We don’t know much about how the brain functions. I always wanted to know more. We hope this will be possible with our smart materials," adds the Nobel laureate.
The link between humans and machines
Potanin joins Tesla Inc.’s Elon Musk in funding the drive into neuromorphic computing, which could ultimately use brain implants to create a high-bandwidth link between humans and machines. Musk’s four-year-old start-up Neuralink Corp. is developing implantable brain-machine interfaces, which he says have the potential to address brain injuries and other disorders.
Potanin, the president and chairman of the board of MMC Norilsk Nickel, says that "we live in the era of artificial intelligence, the emergence of new, absolutely fantastic materials and technologies, and it is very important that in this strategic direction of science, Russia remains in the forefront."
"Future generations will be able to transfer new knowledge in technology to the real economy," he says.
Originally conceived in 2020, the new laboratory will become the first at the Brain and Consciousness Research Centre, whose main goal is to obtain fundamental knowledge about the functioning of the human brain, the nature of consciousness, and the development of related technologies. The centre is headed by Professor Tagir Aushev, a Russian scientist working in the field of fundamental physics.
"The brain, in my opinion, is the most important task of the 21st century for humanity. And all the major discoveries, all major breakthroughs, in my opinion, will be associated with this topic. What our centre will be doing is fundamental brain research and an attempt to understand consciousness," says Aushev.
The lab will study two-dimensional materials - including graphene - to create smart materials and to develop on their basis conceptually new technologies. In particular, these materials will be used to develop new approaches to neuromorphic computing, high-sensitivity sensors and brain-computer interfaces.
© Emerging Europe All Rights.
* * *
Nature / 12 February 2021
Russian academics decry law change that threatens scientific outreach
Researchers say that a proposed amendment could impede collaboration with foreign speakers and scientific literacy.
Российские ученые и преподаватели вузов выступили против предложенных поправок к закону об образовании, согласно которой на образовательную и просветительскую работу с общественностью, в том числе популяризацию науки, потребуется разрешение от федеральных органов. По словам ученых, это поставит под угрозу просветительскую деятельность в России и нанесет ущерб академической свободе и свободе слова.
Scientists and academics in Russia are protesting against a proposed law change that they say will damage academic freedom and free speech. The amendment to Russia’s law on education, which lawmakers say is intended to stop anti-Russian propaganda, would require academics and educators to get permission from state authorities to do public outreach for educational activities, including those involving science. A petition against the change - which Russia’s lower house of parliament, the State Duma, is scheduled to vote on next week - has drawn more than 200,000 signatures, and threats from researchers of civil disobedience because it could curb efforts to grow scientific literacy.
The presidium of the Russian Academy of Sciences - the nation’s primary basic-research organization - has called on Duma members to reject the bill. The suggested changes run counter to efforts to modernize Russian science, academy leaders say. "Activities that enlighten society about scientific achievements are developing rapidly in Russia and scientists consider this mission useful for the whole society," says Alexei Khokhlov, vice-president of the academy. "The proposed law doesn’t support these activities, it gives only restrictions. Any form of restrictions are not helpful for the development of society."
The proposal would grant the government "excessive control" of a range of public teaching and outreach activities that scientists conduct outside formal educational programmes, says Sergei Popov, an astronomer at Lomonosov Moscow State University who launched the online petition. These might include efforts to increase scientific literacy through popular lectures, podcasts and online courses on platforms such as YouTube.
"The proposed amendments are intolerably repressive," says Mikhail Gelfand, a biology lecturer at the Skoltech Center of Life Sciences in Moscow, and a member of the London-based Academia Europaea, which aims to advance science and scholarship.
Scientists are particularly worried about an amendment that would require them to get permission from federal authorities before signing agreements with foreign education partners. The rule would pose unacceptable hurdles for efforts to attract foreign instructors to teach in Russia, says Popov. "I’d need to beg for allowance each time I want to invite a foreign lecturer to a meeting or a summer school," he says. "This is ridiculous, and I will not obey."
Many scientists and educators might stop reaching out to the public for fear that what they say could be against the law, says Alexandra Borissova, co-founder of the Russian Association of Science Communication in Moscow.
But the law should not affect ordinary research activities that involve international collaboration, says Kirill Dmitriev, chief executive of the Russia Direct Investment Fund, the country’s sovereign wealth fund, which backed the development of the Sputnik V COVID vaccine. "This law would not preclude typical collaboration that is part of regular scientific discourse and regular scientific operation, so I think it will have very limited use," he says. "Most scientists in Russia would understand that scientific collaboration is the core of success."
The bill was introduced in November by members of the Duma and comes as Russia’s foreign relations hit a low, following oppression of the opposition leader Alexei Navalny. According to a supplementary note on the bill, the aim of the change is "to counteract the spread of illegal information and anti-Russian propaganda in the school and student environment". The draft law refers explicitly to ethnic- and religious-hate propaganda.
But critics view the change as part of growing efforts by the Russian government to suppress free speech. Hate speech is banned by existing Russian laws, so the amendment is superfluous, says Gelfand. Instead, this change will add extra bureaucracy to Russia’s science, which is already stifled by red tape.
The move mirrors the growing nervousness among Russia’s rulers and lawmakers over dissident voices and foreign agents, says Sergei Guriev, an economist at Sciences Po in Paris, who left Russia in 2013. "This is extremely worrying," he says. "The law is certainly designed against social scientists. Modern economics, political science, sociology and history are very dangerous for the regime, so they are trying to devise tools to selectively censor criticism."
Borissova agrees. If approved, the rules would clearly violate the constitutionally guaranteed freedom of speech, she says. "The presumption is that spreading scholarly knowledge in public could serve ‘anti-Russian’ interests," she says. "This is state interference with the freedom of opinion, and blatantly contrary to efforts to improve scientific literacy."
Hundreds of scientists say they will not follow the new rule, no matter what sanctions they might expect. Some could risk losing their jobs, says Popov.
© 2021 Springer Nature Limited.
* * *
Nuclear Engineering / 15 February 2021
Russia’s Troitsk Institute pushes ahead with thermonuclear and plasma research
В рамках программы «Развитие техники, технологий и научных исследований в области использования атомной энергии на период до 2024 года» к 2030 году в Троицком институте инновационных и термоядерных исследований (ТРИНИТИ) планируется построить термоядерную установку нового поколения.
Russia’s Troitsk Institute of Innovative and Thermonuclear Research (Triniti) in Moscow plans to build a new thermonuclear reactor by 2030, Deputy Director General Kirill Ilyin told Strana Rosatom on 9 February.
The facility will be constructed as part of a wider programme, "Development of equipment, technologies and scientific research in the use of atomic energy for the period up to 2024" (RTTN).
Ilyin said the RTTN programme is a major undertaking and more than half of the institute will be involved in reconstruction activities in preparation.
Triniti (part of Rosatom, and formerly a branch of the Kurchatov Institute) has not seen such capital construction since the1980s. Last year restructuring began and preparatory research got underway, supported by the state programme "Development of the nuclear power-industrial complex", which includes a special section on thermonuclear research and plasma innovative technologies. This laid the groundwork for implementation of activities under RTTN.
"We have developed individual elements of a plasma rocket engine and have created an excellent diagnostic bench for testing these elements," said Ilyin. "We also completed the technical design of a compact installation for plasma processing of materials a - powerful neutron source for testing materials for promising thermonuclear reactors. Our colleagues at the AA Bochvar Research Institute of Inorganic Materials (VNIINM) took the first steps towards creating magnetic systems for electrodeless plasma rocket engines. The Kurchatov Institute began to develop a project for the engine itself. Our partners include the Kurchatov Institute, organisations of the Ministry of Education and Science, and institutes of the Russian Academy of Sciences."
Under the RTTN programme, it is planned to create three versions of plasma rocket engines. While the Kurchatov Institute is responsible for the electrodeless engine, improved ion and Hall thrusters will be developed at the Keldysh Institute of Applied Mathematics (Russian Academy of Sciences) in Moscow.
"Triniti’s task is a plasma rocket engine based on magnetic-plasma accelerators. These devices are needed for different purposes: some will open up new possibilities in low-earth orbit, others will allow you to explore deep space," said Ilyin The cooperation under RTTN is wide, with participants from all over Russia. To better organising interaction, systems will be used that were developed at the Institute of Reactor Materials in Zarechny (formerly the Sverdlovsk branch of the NN Dollezhal Research & Development Institute of Power Engineering - Nikiet).
"There the concept of a networked scientific centre was developed: an association of leading scientific organisations able to solve problems with a more global approach," Ilyin explained. "The concept of a digital platform was established to help track the progress of joint projects. The platform also serves as a communication platform where individuals can coordinate actions within a research framework. Now one part of this concept has been implemented as an industry project - "International Research Centre for Advanced Nuclear Technologies" on Russky Island."
Ilyin said a new-generation fusion facility will be built at Triniti site where the TSP strong-field tokamak is now located. The TSP tokamak began operation in 1987 but was suspended due to lack of funds following the collapse of the USSR. It has four satellite buildings with auxiliary infrastructure. Major reconstruction is planned as part of the RTTN programme. "Four shock generators, cryogenic and vacuum systems, and a cooling system will be modernised, and a test facility has been created that will confirm the capabilities of the infrastructure and test individual elements of tokamaks," he said.
There are two options for further development. The first is the implementation of the Russian-Italian project "Ignitor", which involves the construction of a compact tokamak with an ultra-strong magnetic field. The installation of this project is quite advanced and many calculations have already been carried out. The second option is the construction of a national tokamak using reactor technologies, which could begin in 2022, because a new tokamak must be built at the Triniti site by 2030.
New installations for thermonuclear and plasma research will also be established elsewhere. For instance, the T-15MD tokamak at the Kurchatov Institute will soon start operating at full capacity. All the facilities developed under the RTTN programme will have a common infrastructure. One of the subsections of the plasma-thermonuclear section is devoted to hybrid systems - fusion-fission reactors, which can be used not only to generate electricity, but also to generate fuel and burn minor actinides. By 2024, a draft design of the blanket part of the hybrid reactor must be completed. Another area of research and development is the modification of materials using plasma and laser technologies. Preliminary experiments show that plasma and laser treated metals acquire greater corrosion and wear resistance. Such materials are needed in aviation, in space, and in nuclear power. Work is also underway on laser thermonuclear fusion.
The main participants here are the Russian Federal Nuclear Centre - All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF) in Sarov, where the world's most powerful laser is being built, and the Institute of Applied Physics of the Russian Academy of Sciences. "There are tasks for Trinity here too," said Ilyin. "For example, we are making a prototype of a driver module for a laser at RFNC-VNIIEF."
© 2021, All Rights Reserved.
* * *
Science Codex / February 16, 2021
Scientists of Kemerovo State University have developed a technology for creating in vitro root
Исследователи Кемеровского государственного университета разрабатывают методы культивирования in vitro изолированных клеток и органов редких и эндемичных лекарственных растений Сибири и Дальнего Востока. Это позволит решить проблему дефицита растительного сырья, а также обеспечит его экологическую чистоту.
Scientists of Kemerovo State University, within the framework of the Russian Scientific Foundation grant "Cultivation of isolated cells and organs of rare and endemic medicinal plants of Siberia and the Far East in vitro as a biotechnological method for obtaining biologically active substances", are investigating the fundamental principles of in vitro cultivation of isolated cells and organs of rare medicinal plants - producers of biologically active substances with cytotoxic, antioxidant and antimicrobial properties. One of the urgent problems of medicine and biology is the search and use of plant objects as medicines. The unfavorable environmental situation and the increasing need for medicinal raw materials create its shortage. A new solution was the use of an alternative source of raw materials - cultures of cells and organs of higher plants. The main advantages of this approach are the ecological purity of biomass production by biotechnological method, the possibility of obtaining plant biomass with specified characteristics regardless of the season, climate and weather conditions, high rates of biomass production, guaranteed purity of biomass from pesticides, herbicides, radioactive compounds and other pollutants. The presence of an effective industrial super-producer strain guarantees a higher content of the target product than in an intact plant.
* * *
Under the scope of the project, it has been possible to obtain the collection of callus, suspension cells and in vitro root cultures of medicinal plants of Siberia and the Far East since 2018. These cultures have cytotoxic, antioxidant and antimicrobial properties. Their growth characteristics have been successfully studied. Furthermore, scientists developed in vitro crops cultivation systems, as well as methodology for obtaining target biologically active substances by extraction.
Currently, the work is underway to optimize the secretion conditions and purification of biologically active substance from the callus extracts, suspension cultures of cells and root cultures in vitro. Scientists also selected the conditions for drying isolated BAS. On the completion of the research project, they plan to passport the received biotechnological objects of medicinal plants in Siberia and the Far East. Based on the results of the research project, a technology for creating root cultures in vitro will be presented. These cultivated plants are distinguished by higher content of biologically active substance, which remains the base of high-quality herbal raw materials for medicine and pharmaceutical industries.
SpaceNews / February 17, 2021
Russia, China to sign agreement on international lunar research station
Россия и Китай готовятся подписать меморандум о сотрудничестве в создании международной лунной исследовательской станции.
Russia is preparing to sign a memorandum of understanding with China to cooperate on a vision for an international lunar research station.
* * *
"Roscosmos has completed domestic proceedings to harmonize the Memorandum of Understanding between the Government of the Russian Federation and the Government of People’s Republic of China on cooperation to create the International Lunar Research Station," Roscosmos Press Office told SpaceNews in an email.
"The date to sign the above mentioned MoU has not been determined yet and is currently discussed with the Chinese partners," Roscosmos said. An Order of the Government of the Russian Federation relating to the move was published online Feb. 11.
Roscosmos press office said the official announcement of the plans to create the International Lunar Research Station is planned to coincide with one of the upcoming international events. St. Petersburg is due to host the Global Space Exploration Conference 2021 in June.
Roscosmos did not provide requested further details on the makeup of, nor contributions to the International Lunar Research Station.
The ILRS is understood to be a Chinese-developed vision for a robotic base at the lunar south pole. The first steps will be the upcoming Chang’e-,6, -7 and -8 missions and international missions such as Russia’s Luna 27. In the early 2030s an expanded ILRS will involve long-term robotic and potentially short-term crewed missions. A long-term human presence at the lunar south pole is the goal for 2036-2045.
The project, at this early stage, would appear to consist of Chinese, Russian and potentially other nations contributing their own, discrete spacecraft. This would be in contrast to a more complex, integrated program such as the International Space Station.
ILRS objectives include "construction and operation of human[ity]’s first sharing platform in the lunar south pole, supporting long-term, large-scale scientific exploration, technical experiments and development and utilization of lunar resources’, according to a 2020 presentation to the Scientific and Technical Subcommittee of the Committee on the Peaceful Uses of Outer Space (COPUOS) by the Lunar Exploration and Space Engineering Center under the China National Space Administration (CNSA).
From Gateway to China-Russia lunar station
The development follows Russia opting not to join eight nations, including the U.S., in signing on to the Artemis Accords last October. The Accords are a set of principles and norms for those who want to participate in the NASA-led Artemis lunar exploration program.
Bleddyn Bowen, a lecturer in international relations at the University of Leicester in the United Kingdom, told SpaceNews that the development is not such a surprise, given that Russia has always been lukewarm to the Lunar Gateway, part of the Artemis program, and this will have been factored in. However the project will still suffer from the loss of Russian expertise.
Bowen sees the move from Russia as an ISS partner to working more closely with China in lunar exploration rather than ISS partners is part of wider space-related and geopolitical shifts, particularly since the outbreak of the Ukranian conflict.
"This MoU fits the larger trend, which is Russia moving into a closer orbit with China," says Bowen, adding that this more formal agreement builds on existing cooperation in material science, data sharing, purchase agreements and lunar exploration.
Bowen cautions however that this is "just a memorandum of understanding, so we’ll have to wait and what, if anything, comes from this".
Zhang Ming, a researcher on international security and space issues at the Shanghai Academy of Social Sciences, told SpaceNews both China and Russia, who have long cooperated in space, have difficulties in working with the U.S. for different reasons. Zhang notes that Russia had expressed concerns that Artemis was too "U.S.-centric" and she would expect "more and more space and lunar cooperation between Russia and China" if the "United State continues its space policies and practices without any change."
"The U.S. advances its space agenda aggressively and sometimes unilaterally in recent years despite the concerns of the rest [of the] world, which made China and Russia very worried. The mistrust and skepticism towards U.S. motives will promote China and Russia to further their space cooperation," Zhang said.
Roscosmos chief Dmitry Rogozin last year told Russian media China and Russia had agreed they will "probably" build a moon research base together, following talks with Director of the China National Space Administration Zhang Kejian.
Brian Weeden of the Secure World Foundation also believes the split has been coming for sometime, citing the Ukraine invasion and 2016 election interference. "I think we’re at a much different US-Russia space relationship than we had for the past few decades."
"I don’t think it’s going to have a serious impact on Artemis. Russia indeed has some experience in robotic lunar landers but no human spaceflight experience and their space sector has been declining for some time," says Weeden. "The space partnership with Russia in the ISS was driven more by national security and foreign policy reasons than a need to have Russian expertise. It’s useful, but not critical."
The European Space Agency has also been involved in discussions, while recently having signed an MoU with NASA on the Gateway. "At ESA we are following the Chinese lunar exploration plans very closely in order to see where our respective programmatic interest could meet, primarily the CE-6, -7 and -8 missions but also the ILRS initiative", Karl Bergquist, ESA’s international relations administrator, told SpaceNews last year.
From Chang’e to ILRS
The ILRS is an evolutionary, expanded stage of Chinese lunar exploration following the approval of a first set of missions in the early 2000s. China has since launched two lunar orbiters, a pair of lander and rover missions and, in late 2020, the complex Chang’e-5 lunar sample return mission.
Chang’e-6, a polar sample return mission, and the multi-spacecraft Chang’e-7 are scheduled for around 2023-2024. The later Chang’e-8 mission will be designed for in-situ resource utilization and 3D-printing technology tests, as well as life science related to potential long-term stays on the moon. These missions will form the robotic basis of the ILRS before expansion into more long term base.
China is also developing capabilities for deep space human spaceflight. In May 2020 China tested a new generation spacecraft and is also developing a super-heavy-lift launcher for space infrastructure and lunar missions. A new, three-core launcher for potential crewed lunar missions is also in development.
HeritageDaily / February 17, 2021
Archaeologists Excavate Burial Mound Containing Scythian Grave Goods
При раскопках кургана в Ростовской области археологи Донского государственного технического университета и Южного научного центра РАН обнаружили скифское захоронение IV века до н. э. Вместе со знатным человеком или вождем были похоронены воин и конь.
Archaeologists from the Don State Technical University, and the Southern Scientific Centre of the Russian Academy of Science have excavated a burial mound containing Scythian Grave Goods.
The Scythians, also known as Scyth, Saka, Sakae, Iskuzai, or Askuzai were an ancient nomadic people of Eurasia that mainly centred on the Pontic steppe from about the 7th century BC until the 3rd century BC.
Research of a cluster of burials in the area between the Don and Kagalnik rivers in the Rostov region of Russia have been under continuous study since 1967, with the latest series of excavations focusing on a large mound containing medieval, Bronze Age, and Scythian burials.
Near the mound, archaeologist have found an assemblage of bronze adzes (a type of cutting tool), and a polished stone axe from the Cimmerian period during the 8-7th century BC.
In the centre of the mound was the disturbed burial of a Scythian noble from the 4th century BC, and the accompanying remains of a tribal warrior buried with an ornate gold chain and a small cast horse.
Near the warrior, the team also found two spears, a large iron sword decorated on the hilt with gold foil, a wooden sheath, a sling, a quiver, a bronze cauldron, and several broken arrows associated with the funerary practice of sprinkling broken arrows over the deceased by a priest.
The burial of the cast horse was located in a higher context, ordained with deer antlers and decorated with a style that is typical for the tribes of the Urals or Altai Mountains.
The remains from the burials will be sent for anthropological analysis, where experts will examine the teeth to try and determine the sex, age, and insights into the diet and health.
© 2020 - HeritageDaily.
* * *
National Post / Feb 17, 2021
Russian scientists seek ancient viruses in body of frozen 4,500-year-old Siberian horse
Paleovirus research aims to understand virus evolution.
ГНЦ «Вектор» и Северо-Восточный федеральный университет начали совместную работу по поиску и выделению палеовирусов из мягких тканей ископаемых животных, найденных в вечной мерзлоте. Первым объектом исследования станет доисторическая лошадь возрастом 4,5 тысячи лет.
The remains of a 4,500-year-old horse, found in melted Siberian permafrost in 2009, is undergoing analysis in a Russian lab researching ancient viruses.
A former centre for the development of biological weapons in Soviet times, the Vektor laboratory is one of only two facilities in the world to store the smallpox virus, and has developed the EpiVacCorona vaccine, which is scheduled to begin mass production later this month.
But in collaboration with the University of Yakutsk, the lab in the Novosibirsk region is now searching for paleoviruses in prehistoric animals, including mammoths, elk, dogs, partridges, rodents and hares, furthering study into virus evolution.
The chief of the university’s Mammoth Museum lab, Maxim Cheprasov, said in a press release that the recovered animals had already been the subject of bacterial studies. "We are conducting studies on paleoviruses for the first time."
Finding prehistoric animals in permafrost is happening more often as climate change warms the Arctic at a faster pace than the rest of the world, thawing the ground in some areas that have stored ancient viruses for millennia.
In Siberia’s region of Yakutia, melting permafrost was likely to yield up even more treasures, The Guardian reported in 2016, with the number of reported prehistoric finds rising "severalfold" in the previous decade as warm and wet weather contributed to the thaw. A pair of frozen three-month-old puppies found in 2011 drew global interest to scientific and cultural secrets to be gleaned from such animals.
In Russia, indigenous peoples have rights to hunt for ancient remains on ancestral lands. They now search for mammoth tusks to sell direct to China, where the ivory - now in demand, given trade bans on elephant ivory - is fashioned into jewellery, trinkets, knives and other decorations, the Guardian says.
Woolly mammoth ivory up to 30,000 years old and preserved in the permafrost in the Yakutia region makes up 80 per cent of Russia’s trade in a largely unregulated market worth more than US$50 million a year, Russian officials told the Guardian. If any paleoviruses still exist in the animals and are able to revive themselves, any number of unknown diseases could be released.
In other parts of the world, scientists are studying glacial microbes. Two ice core samples from 50 metres deep in the Guliya ice cap on the Tibetan Plateau were collected in 1992 and 2015, and analysis revealed 33 groups of virus genuses. Of these, 28 were previously unknown to science. According to the study, melting glaciers are releasing microbes and viruses that have been trapped for tens to hundreds of thousands of years.
Chantal Abergel, a researcher in environmental virology at the French National Centre for Scientific Research, led a team that revived a 30,000-year-old giant virus from permafrost, showing that it could still infect its target, a single-celled amoeba.
© 2021 National Post, a division of Postmedia Network Inc. All rights reserved.
* * *
CNN / February 17, 2021
Mysteries of massive holes forming in Siberian permafrost unlocked by scientists
Ученые из Института проблем нефти и газа РАН, Сколковского института науки и технологии и Российского центра освоения Арктики опубликовали результаты исследования обширного кратера, образовавшегося на Ямале в прошлом году после выброса метана. Всего с 2013 года подобным образом возникло 17 кратеров. Поскольку последний кратер совсем «свежий» и еще не заполнен водой, ученым впервые удалось запустить туда дрон. На основе полученных снимков была создана 3D модель кратера, в том числе форма подземной полости, где скапливался метан. Однако его источник пока остается невыясненным.
The massive crater appeared violently and explosively in the Siberian tundra last year - a powerful blowout of methane gas throwing ice and rock hundreds of feet away and leaving a gaping circular scar in the empty and eerie landscape.
It was the 17th hole to appear in the remote Yamal and Gyda peninsulas in the Russian Arctic since the first was spotted in 2013, mystifying scientists. The craters are thought to be linked to climate change. Drone photography, 3D modeling and artificial intelligence are helping to reveal their secrets.
"The new crater is uniquely well preserved, as surface water hadn't yet accumulated in the crater when we surveyed it, which allowed us to study a 'fresh' crater, untouched by degradation," said Evgeny Chuvilin, lead research scientist at the Skolkovo Institute of Science and Technology's Center for Hydrocarbon Recovery in Moscow. It was also the first time researchers have been able to fly a drone deep into a crater - reaching 10 to 15 meters below ground, allowing them to capture the shape of the underground cavity where methane had built up. Chuvilin was part of a team of Russian scientists who visited the crater in August 2020. Their findings were published in the journal Geosciences last week.
The drone took around 80 images, allowing the researchers to build a 3D model of the crater, which is 30 meters deep - imagine three buses end to end. Study author Igor Bogoyavlensky, of the Oil and Gas Research Institute of the Russian Academy of Sciences, served as the drone pilot and said he had to lie down on the edge of the 10-story deep crater and dangle his arms over the edge to control the drone.
"Three times we got close to losing it, but succeeded in getting the data for the 3D model," he said.
The model, which showed unusual grottoes or caverns in the lower part of the crater, largely confirmed what scientists had hypothesized: Methane gas builds in a cavity in the ice, causing a mound to appear at ground level. The mound grows in size before blowing out ice and other debris in an explosion and leaving behind the massive crater. What's still unclear is the source of the methane. It could come from deep layers within the Earth or closer to the surface - or a combination of the two.
Permafrost is a huge natural reservoir of methane, a potent greenhouse gas much more effective than carbon dioxide at trapping heat and warming the planet. Warmer summers - the Arctic is warming two times faster than the global average - have weakened the permafrost layer, which acts as a cap, making it easier for gas to escape. Some experts estimate that soils in the permafrost region hold twice as much carbon as the atmosphere does, making the region extremely important in the fight against climate change.
"Climate change, of course, has an impact on the probability of gas blowout craters appearing in the Arctic permafrost," Chuvilin said.
With the use of satellite imagery, the researchers were also able to pinpoint when the crater formed. They believe the mound would have exploded at some point between May 15 and June 9, 2020. The crater was first spotted during a helicopter flight on July 16, 2020. The timing was not random, according to Chuvilin. "This is the time of the year when there's a lot of solar energy influx, which causes the snow to melt and the upper layers of the ground to heat up, and that causes changes in their properties and behavior."
While these craters have appeared in a very sparsely populated region, they do pose risks to Indigenous people and to oil and gas infrastructure. The holes are usually found by accident during helicopter flights or by reindeer herders.
Mapping and predicting crater blowouts
While 17 craters have been documented so far, it's not known how many there are in total or when the next one could blow out. Scientists don't yet have good tools for detecting and mapping the gas emission craters, although a team at the Woodwell Climate Research Center in Massachusetts is trying to change that. To log changes in the Arctic landscape, and perhaps ultimately predict where the next blowout crater might occur, the researchers have devised an algorithm to quantify changes to features such as the height of mounds and the expansion or shrinking of lakes on the Yamal and Gyda peninsulas.
The scientists' model correctly predicted all seven craters that had been reported by scientists by 2017 and revealed the formation of three new ones. The researchers also found that the craters are just one unsettling sign that the northernmost reaches of our planet are undergoing radical changes. Some 5% of the 327,000 square kilometers the team surveyed saw abrupt changes in landscape between 1984 and 2017. These changes included ground collapses, the formation of new lakes and disappearance of others, plus the erosion of river bends, according to the research, which published in the Geosciences journal in January.
"These craters represent a ... process that was previously unknown to scientists," said Sue Natali, Arctic program director at the Woodwell Climate Research Center and coauthor of the study, in a statement.
"The craters and other abrupt changes occurring across the Arctic landscape are indicative of a rapidly warming and thawing Arctic, which can have severe consequences for Arctic residents and globally."
© 2021 Cable News Network.A Warner Media Company. All Rights Reserved.
* * *
The Academic Times / February 17, 2021
Orbital lasers could melt defunct satellites without polluting space
60% из почти 6000 спутников Земли больше не работают и попросту занимают орбиту. Российский физик Егор Локтионов из МГТУ им. Н.Э.Баумана предложил необычный способ избавиться от космического мусора - плавить его лазером до состояния плазмы, для безопасности направляя излучение не с Земли, а непосредственно из космоса. После этого полученную плазму можно будет использовать в качестве топлива для космических аппаратов с лазерными двигателями.
Although 60% of Earth’s nearly 6,000 satellites are non-operational and needlessly occupying the planet's orbit, attempts to remove this "space junk" are sparse. But a Russian physicist has been fine-tuning a method to eliminate defunct satellites - using space-borne lasers to melt them into plasma - to ensure it won't inadvertently create even more debris.
Egor Loktionov is the laboratory head of Bauman Moscow State Technical University and lead author of a new study about this work that is forthcoming in the April issue of Acta Astronautica. He explained to The Academic Times that his team members have been testing a variety of spacecraft materials that they believe could become satellite laser targets to see how the materials react when exposed to laser pulse emissions, also called irradiation. They found that solar cells could pose a hazard, but propose that using lasers in space rather than on land could address this potential concern.
Loktionov has thoroughly researched the use of laser pulses to melt space junk, also called space debris, into plasma. The researcher believes this technique, referred to as laser ablation, is the ideal way to reduce the number of useless objects in our orbit, such as defunct satellites.
"Many ways to capture debris have been suggested to date, few are tested and none really practiced," Loktionov said. "Laser space debris removal, to my mind, should provide a cheaper, more reliable and flexible way to do the job."
Laser ablation isn't a new concept; it's often used to address medical concerns such as small tumor removal. In research published in 2019, Loktionov took this concept a step further by proposing its use on a grander scale, as a cost-effective and environmentally friendly remedy to the issue of space debris, because the lasers are reusable.
"In general, the space debris problem is getting more and more pronounced, particularly with launching thousands of CubeSats and internet projects like OneWeb and Starlink," Loktionov said.
In 2020 alone, Elon Musk’s SpaceX deployed more than 800 satellites to support his broadband internet system endeavor, Starlink. As technology progresses, so will the need for satellites. And as satellites are released, Loktionov warns that space debris removal will become a necessity rather than an option.
Loktionov's stance on targeted laser ablation for the destruction of defunct satellites has been widely researched. For instance, Chinese physicists created numerical simulations in 2018 to study the effectiveness of a space-based laser. The idea is also entertained by some space organizations, including Russian agency Roscosmos, as a practical mechanism to solve the ongoing issue of space debris accumulation.
Even though Loktionov's team plans to test additional materials, as the first to gauge the impact of irradiation on solar cells, the researchers found that their results required immediate publication - especially for space agencies that may be inclined to move forward with the proposed mechanism.
"If solar array grinding is not considered, one big detectable and manageable piece can be turned into a cloud of small pieces almost impossible to clean out," Loktionov stressed.
Solar cells are present on satellites as their characteristic solar arrays, and the paper heavily emphasizes that these arrays should be avoided when positioning lasers. However, the authors maintain that as long as pulses are emitted away from the panels, laser ablation remains tenable as a method of obliterating defunct satellites.
Loktionov recommends that agencies use a space-borne laser to ensure that solar arrays are not hit by pulses. Such a laser would increase point accuracy by circumventing atmospheric interference that would otherwise distort the laser beams and therefore lower pulse precision, he says.
"Ground-based [lasers] might appear easier, but those cannot provide a small spot due to distance and passing through the atmosphere. This means solar arrays would almost inevitably be irradiated," Loktionov said. "We suggest considering more precise impact with space-borne lasers or our recycling concept."
That concept calls back to Loktionov's 2019 research, in which he argued that space debris, melted into plasma, could potentially be recycled as fuel for spacecraft powered by laser thrusters. That's because the thrusters would be able to accept a variety of fuels, including the plasma byproduct of laser ablation, providing a cost-effective way to rewrite the problem of space debris as a useful tool.
This technology could also reduce risks to humans and obstacles to other important spacecraft, Loktionov pointed out.
Releasing a single satellite into space requires millions of dollars purely for the send-off, and depending on the weight of the vehicle, costs can reach an astounding $400 million. But despite the generous sum dedicated to the beginning of a satellite’s tenure, space agencies place little emphasis on managing the end, when the spacecraft become dysfunctional and are deemed space junk. Often, the craft are left in orbit until they explode, which creates other pieces of debris that can threaten orbiting spacecraft that are still in use.
If taken care of, the debris is either moved to an empty orbit called a graveyard orbit or burnt upon re-entry into the atmosphere. The latter can endanger humans if shards of the burnt spacecraft fall to Earth.
© 2020 Fastinform, Inc.
* * *
Trust My Science / 26 février 2021
Tous les neutrinos astrophysiques de haute énergie seraient issus des quasars
Космические нейтрино делятся на две категории: с высокой и очень высокой энергией. Считается, что первые возникают во время космических процессов разного уровня, а вторые - в квазарах вблизи черных дыр. Однако российские физики из Института ядерных исследований РАН, Физического института имени П.Н.Лебедева РАН и Московского физико-технического института, используя данные детектора нейтрино IceCube, показали, что квазары испускают нейтрино обеих категорий, несмотря на то, что для этого требуются разные условия.
Les modèles astrophysiques établis au cours des dernières décennies classent les neutrinos astrophysiques en deux catégories : les neutrinos de haute (téraélectronvolt, TeV) et de très haute (pétaélectronvolt, PeV) énergies. Les premiers sont censés être produits lors d’événements cosmiques d’ampleur variable, tandis que les seconds sont réputés être issus des quasars. Cependant, des physiciens russes ont montré que cette distinction serait en réalité incorrecte. À l’aide de données issues du détecteur de neutrinos IceCube, les chercheurs ont montré que tous les neutrinos de haute et très haute énergies proviendraient en fait des quasars. La même source cosmique serait alors responsable de la production de tous les neutrinos astrophysiques d’énergie égale et supérieure au TeV.
Des physiciens de l’Institut de physique PN Lebedev de l’Académie russe des sciences (LPI RAS), de l’Institut de physique et de technologie de Moscou (MIPT) et de l’Institut de recherche nucléaire de RAS (INR RAS) ont étudié les directions d’arrivée des neutrinos astrophysiques avec des énergies de plus d’un billion d’électronvolts (TeV) et sont arrivés à une conclusion inattendue : tous sont nés à proximité de trous noirs situés dans les centres de galaxies actives éloignées. Auparavant, seuls les neutrinos aux énergies les plus élevées étaient supposés être produits dans les sources de cette catégorie.
On pense qu’il existe des trous noirs massifs dans les centres des galaxies actives de notre Univers. Ils sont le cœur de ces systèmes galactiques, avec une luminosité de centaines de millions de soleils. Les galaxies actives, également appelées quasars, sont clairement visibles depuis la Terre avec des télescopes optiques et radio.
Antérieurement, les scientifiques russes Alexander Plavin, Sergey Troitsky et les Kovalev (père et fils, tous deux nommés Yuri) avaient trouvé un lien entre l’origine des neutrinos des énergies les plus élevées (à l’échelle TeV) et les quasars radio. C’était assez surprenant, car les articles théoriques des années 1990 indiquaient que les neutrinos astrophysiques ne naissaient qu’à des énergies supérieures à 1000 TeV.
Les neutrinos sont des particules élémentaires avec une masse à peine supérieure à zéro, mais ils peuvent traverser l’Univers pratiquement sans interagir avec la matière. Des millions de neutrinos par seconde traversent chaque personne et chaque objet sur Terre. Pour enregistrer les neutrinos, une collaboration internationale de scientifiques a construit un détecteur spécial en Antarctique : le détecteur Tcherenkov IceCube d’un volume de 1 kilomètre cube.
IceCube révèle des neutrinos astrophysiques issus des quasars
En Russie, l’INR RAS et le JINR achèvent actuellement la construction du télescope aquatique Baikal GVD dans le lac Baïkal, dont le volume atteint déjà 400 m3. Désormais, l’acquisition de données est en cours sur la partie courante de l’installation, déjà mise en service. Ces installations étudient le ciel dans différents hémisphères.
Après avoir analysé les données collectées pendant 7 ans sur le détecteur IceCube, les chercheurs ont d’abord choisi d’analyser une plage supérieure à 200 TeV pour étudier la direction de ces neutrinos. Il s’est avéré qu’une partie importante d’entre eux était née dans des quasars, identifiés par les radiotélescopes via leur haute luminosité. Plus précisément, les neutrinos sont nés quelque part dans les centres des quasars. Il y a des trous noirs massifs alimentant leurs disques d’accrétion, ainsi que des éjections ultrarapides de gaz très chauds.
De plus, il existe un lien entre les puissants sursauts d’émission radio dans ces quasars et la détection des neutrinos par le télescope IceCube. Puisque les neutrinos voyagent à travers l’Univers à une vitesse proche de celle de la vitesse de la lumière, les sursauts radio nous parviennent pratiquement en même temps que les neutrinos.
Quasars : ils seraient la source de tous les neutrinos astrophysiques de haute énergie
Dans leur nouvel article publié dans la revue The Astrophysical Journal, les physiciens russes soutiennent que les neutrinos d’énergies de dizaines de TeV sont également émis par les quasars. En conséquence, il s’avère que tous - enfin, presque tous - les neutrinos astrophysiques de haute énergie sont nés dans des quasars. En plus de ceux-ci, il y a des neutrinos qui naissent dans l’atmosphère terrestre, et même dans le détecteur IceCube lui-même lors de l’interaction des rayons cosmiques avec la matière.
« C’est étonnant, car pour la production de neutrinos avec des énergies qui diffèrent d’un facteur 100-1000, différentes conditions physiques sont nécessaires. Les mécanismes de production de neutrinos dans les noyaux galactiques actifs discutés précédemment ne fonctionnaient qu’à des énergies élevées. Nous avons proposé un nouveau mécanisme de production de neutrinos dans les quasars, ce qui explique les résultats obtenus. Bien qu’il s’agisse d’un modèle approximatif, il est nécessaire de travailler dessus, d’effectuer une simulation par ordinateur », explique Sergey Troitsky, chercheur à l’INR RAS.
La connexion entre les neutrinos et les quasars radio a suscité un grand intérêt dans le monde. Le travail conjoint de scientifiques russes avec l’expérience de neutrinos ANTARES en mer Méditerranée commence. Un article récent de scientifiques européens et américains a confirmé indépendamment la découverte de l’équipe russe utilisant des données de radiotélescope aux États-Unis et en Finlande. Les nouveaux événements de l’arrivée des neutrinos astrophysiques sont désormais suivis par les plus grands radiotélescopes et réseaux d’antennes du monde.
© 2020 Trust My Science. All rights reserved.
* * *
SciTechDaily / February 28, 2021
Quantum Tunneling in Graphene Advances the Age of High Speed Terahertz Wireless Communications
Физики Московского физико-технического института, Московского педагогического государственного университета и Манчестерского университета создали высокочувствительный детектор терагерцового излучения на основе туннельного транзистора из двух слоев графена. Полученное устройство показало очень высокую чувствительность, на несколько порядков больше, чем обычный транзистор, и по мнению ученых, это не предел.
Scientists from MIPT, Moscow Pedagogical State University and the University of Manchester have created a highly sensitive terahertz detector based on the effect of quantum-mechanical tunneling in graphene. The sensitivity of the device is already superior to commercially available analogs based on semiconductors and superconductors, which opens up prospects for applications of the graphene detector in wireless communications, security systems, radio astronomy, and medical diagnostics. The research results are published in a high-rank journal Nature Communications.
Information transfer in wireless networks is based on the transformation of a high-frequency continuous electromagnetic wave into a discrete sequence of bits. This technique is known as signal modulation. To transfer the bits faster, one has to increase the modulation frequency. However, this requires a synchronous increase in carrier frequency. A common FM-radio transmits at frequencies of hundred megahertz, a Wi-Fi receiver uses signals of roughly five gigahertz in frequency, while the 5G mobile networks can transmit up to 20 gigahertz signals.
This is far from the limit, and a further increase in carrier frequency admits a proportional increase in data transfer rates. Unfortunately, picking up signals with hundred gigahertz frequencies and higher is an increasingly challenging problem.
A typical receiver used in wireless communications consists of a transistor-based amplifier of weak signals and a demodulator that rectifies the sequence of bits from the modulated signal. This scheme originated in the age of radio and television, and becomes inefficient at frequencies of hundreds of gigahertz desirable for mobile systems. The fact is that most of the existing transistors aren’t fast enough to recharge at such a high frequency.
An evolutionary way to solve this problem is just to increase the maximum operation frequency of a transistor. Most specialists in the area of nanoelectronics work hard in this direction. A revolutionary way to solve the problem was theoretically proposed in the beginning of 1990’s by physicists Michael Dyakonov and Michael Shur, and realized, among others, by the group of authors in 2018. It implies abandoning active amplification by transistor, and abandoning a separate demodulator. What’s left in the circuit is a single transistor, but its role is now different. It transforms a modulated signal into bit sequence or voice signal by itself, due to non-linear relation between its current and voltage drop.
In the present work, the authors have proved that the detection of a terahertz signal is very efficient in the so-called tunneling field-effect transistor. To understand its work, one can just recall the principle of an electromechanical relay, where the passage of current through control contacts leads to a mechanical connection between two conductors and, hence, to the emergence of current. In a tunneling transistor, applying voltage to the control contact (termed as ‘’gate’’) leads to alignment of the energy levels of the source and channel. This also leads to the flow of current. A distinctive feature of a tunneling transistor is its very strong sensitivity to control voltage. Even a small "detuning" of energy levels is enough to interrupt the subtle process of quantum mechanical tunneling. Similarly, a small voltage at the control gate is able to "connect" the levels and initiate the tunneling current.
"The idea of a strong reaction of a tunneling transistor to low voltages is known for about fifteen years," says Dr. Dmitry Svintsov, one of the authors of the study, head of the Laboratory of 2D Materials for Optoelectronics at the MIPT center for Photonics and 2D materials. "But it’s been known only in the community of low-power electronics. No one realized before us that the same property of a tunneling transistor can be applied in the technology of terahertz detectors. Georgy Alymov (co-author of the study) and I were lucky to work in both areas. We realized then: if the transistor is opened and closed at a low power of the control signal, then it should also be good in picking up weak signals from the ambient surrounding. "
The created device is based on bilayer graphene, a unique material in which the position of energy levels (more strictly, the band structure) can be controlled using an electric voltage. This allowed the authors to switch between classical transport and quantum tunneling transport within a single device, with just a change in the polarities of the voltage at the control contacts. This possibility is of extreme importance for an accurate comparison of the detecting ability of a classical and quantum tunneling transistor.
The experiment showed that the sensitivity of the device in the tunneling mode is few orders of magnitude higher than that in the classical transport mode. The minimum signal distinguishable by the detector against the noisy background already competes with that of commercially available superconducting and semiconductor bolometers. However, this is not the limit - the sensitivity of the detector can be further increased in "cleaner" devices with a low concentration of residual impurities. The developed detection theory, tested by the experiment, shows that the sensitivity of the "optimal" detector can be a hundred times higher.
"The current characteristics give rise to great hopes for the creation of fast and sensitive detectors for wireless communications," says the author of the work, Dr. Denis Bandurin. And this area is not limited to graphene and is not limited to tunnel transistors. We expect that, with the same success, a remarkable detector can be created, for example, based on an electrically controlled phase transition. Graphene turned out to be just a good launching pad here, just a door, behind which is a whole world of exciting new research. "
The results presented in this paper are an example of a successful collaboration between several research groups. The authors note that it is this format of work that allows them to obtain world-class scientific results. For example, earlier, the same team of scientists demonstrated how waves in the electron sea of graphene can contribute to the development of terahertz technology. "In an era of rapidly evolving technology, it is becoming increasingly difficult to achieve competitive results." - comments Dr. Georgy Fedorov, deputy head of the Laboratory of Nanocarbon Materials, MIPT, "Only by combining the efforts and expertise of several groups can we successfully realize the most difficult tasks and achieve the most ambitious goals, which we will continue to do."
Copyright © 1998-2021 Scitechdaily. All Rights Reserved.
* * *