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Российская наука и мир (по материалам зарубежной электронной прессы) |
The Barents Observer / May 04, 2021
Scientists fear more lung cancer as radon is released from thawing permafrost Scientists from the Russian Academy of Sciences hypothesize that as the melting of the permafrost becomes more prevalent, so will the incidence of lung cancer.
- By Polina Leganger Bronder
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По мере таяния вечной мерзлоты высвобождается не только метан, но и радиоактивный газ радон, продукт распада урана в подземных месторождениях. Ученые Федерального исследовательского центра комплексного изучения Арктики РАН опасаются, что повышение концентрации радона в атмосфере может привести к росту заболеваемости раком легких, поскольку этот газ считается вторым по значимости (после курения) фактором развития болезни. Кроме того, вечная мерзлота является естественным резервуаром ртути, которая в результате таяния может попасть в воду.
Massive amounts of uranium are stored in high concentrations underground throughout the Arctic zone. A product of uranium decay is radon gas. Normally, radon is contained in the soil by layers of ground and snow atop of it. However, as permafrost thaws, the radioactive gas seeps out from underground and is released into the atmosphere.
The link between thawing permafrost and increased risk of lung cancer is presented by researchers with the Federal Center for Comprehensive Study of the Arctic with the Russian Academy of Science.
When humans respire radon gas, their lungs are exposed to radiation. Radon is naturally present in air in small amounts. On average, about 0.4 pCi/L of radon can be expected to compose the air. In such small amounts, breathing in radon is fairly harmless, according to the U.S. Environmental Protection Agency (EPA). However, through constant exposure to the gas or to more concentrated quantities of it, the lining of the lungs get damaged. This in turn, increases the chances of developing lung cancer. According to EPA, radon gas is the second greatest contributor to lung cancer after smoking.
Permafrost thawing caused by climate changes is going to increase atmospheric radon levels, which will have horrible health effects on humans and animals in the region, according to the Russian science study.
As radon gas is both odorless and colorless, it is difficult to sensory identify. Arctic animals will not instinctively know that they are in danger. They are likely to continue living in the area but will be increasingly dying prematurely due to higher cancer rates. Local populations will also have difficulty identifying dangerously high levels of the gas without the proper equipment.
It is predicted that if temperatures in the Arctic continue increasing at the pace they have up until now, by the end of the century, about 2.5 million square miles of permafrost will melt. That is 40% of the world’s total permafrost, according to estimates by researchers at the Yale University. The Arctic Institute estimates that in the case of global temperatures increasing by 3 degrees Celsius, up to 85% of the Arctic’s top permafrost layers will thaw.
However, radon gas emissions are far from the sole consequence of diminishing permafrost. Permafrost is also a natural reservoir of mercury. In the Arctic region alone, approximately 700 million liters of mercury are accumulated in the soil. When Arctic soil thaws due to climate change, mercury will permeate into water, be absorbed by organisms and eventually travel up the food chain to humans. Exposure to mercury has negative, and at times fatal, effects on the health of humans, especially on their nervous, digestive and immune systems.
The Arctic’s permafrost is additionally one of the world’s largest carbon sinks and holds an approximate 1,400 gigatons of carbon. With increased regional temperatures, these carbon sinks can enter the atmosphere and further increase global temperatures due to the greenhouse effect. Thawing permafrost will also destroy the Arctic’s infrastructure as well as change the region’s terrain and ecosystems beyond repair.
Atmospheric radon gas increase is yet another frightening side effect of climate change to be added to the myriad of the already existing ones. As the evidence of doom amasses, it is necessary to act before it is too late.
© 2002-2021.
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Российские нейробиологи получили первые научные подтверждения существования буддийского феномена посмертной медитации «тукдам». Суть его состоит в том, что в течении нескольких дней и даже недель у человека, умершего в состоянии глубокой медитации, не происходит распада тканей. Исследования, проведенные среди буддийских монахов на Тибете, показали, что тело человека в состоянии тукдам действительно отличается от состояния тел с аналогичными сроками после смерти. Объяснений явлению пока нет - первоначальная гипотеза об остаточной активности мозга не подтвердилась.
His Holiness the Dalai Lama last week conducted an in-depth online dialogue with Russian neuroscientists to discuss their ongoing research into the Buddhist phenomenon and practice of thukdam meditation.
The term thukdam, derived from the Tibetan words thuk, meaning mind, and dam, meaning samadhi, describes an advanced type of tantric meditation in the Vajrayana tradition practiced by a Buddhist adept during the intermediate or transitional state of death known as bardo. During this period, when biological signs of life have ceased yet the body remains fresh and intact for several days, the master is described as being absorbed in the primordial "clear light stage," a process of inner dissolution. In 2018, the Dalai Lama initiated a scientific inquiry into the neurophysiological mechanisms of thukdam.
"We need to undertake more research and investigate more cases of thukdam to establish whether the visions are associated with dissolution of the coarser elements," His Holiness said during the dialogue on 5 May. "Since it is observed that the body of a person going through this process can remain warm, it may be that the dissolution of the earth, water, and fire elements do not coincide with the three visions." (His Holiness the 14th Dalai Lama of Tibet)
In his widely praised book The Tibetan Book of Living and Dying, the Tibetan Dzogchen teacher Sogyal Lakar explains:
"A realized practitioner continues to abide by the recognition of the nature of mind at the moment of death, and awakens into the Ground Luminosity when it manifests. He or she may even remain in that state for a number of days. Some practitioners and masters die sitting upright in that state for a number of days. Some practitioners and masters die sitting upright in meditation posture, and others in the "posture of the sleeping lion." Besides their perfect poise, there will be other signs that show they are resting in the state of the Ground Luminosity: There is still a certain color and glow in their face, the nose does not sink inward, the skin remains soft and flexible, the body does not become stiff, the eyes are said to keep a soft and compassionate glow, and there is still a warmth at the heart. Great care is taken that the master’s body is not touched, and silence is maintained until he or she has arisen from this state of meditation."
The participants of the dialogue with His Holiness included monk researchers from Sera Je, Me, Gaden Jangtse, Shartse, Drepung Gomang, Loseling, Tashi Lhunpo, Gyume, and Gyuto Monasteries in India. Also present were Natalia Inozemtseva, deputy director of Save Tibet Foundation, Russia; Prof. Svyatoslav Medvedev of the Russian Academy of Sciences and founder of the Institute of the Human Brain in St. Petersburg; Prof. Alexander Kaplan, head of the Laboratory for Neurophysiology and Neuro-Computer Interfaces at Moscow State University (MSU); Konstantin Anokhin, director of the Institute for Advanced Brain Studies, MSU; Yulia Boitsova, researcher at the Laboratory of Neurovisualization, Institute of Human Brain, St. Petersburg; Geshe Ngawang Norbu of Sera Je Monastery and supervisor of the Russian Science Center; Lobsang Phuntsok, a monk-researcher at Sera Je Monastery; and project coordinator Telo Tulku Rinpoche, the shadjin lama (head lama) of Kalmykia and honorary representative for the Dalai Lama in Russia, Mongolia, and members of the Commonwealth of Independent States.
During the audience with the Dalai Lama, Prof. Medvedev of the Russian Academy of Sciences gave a summery of the research activities of his team. Through research laboratories in Tibetan settlements in Bylakuppe and Mundgod, in the southwestern Indian state of Karnataka, the neuroscientists have examined 104 monks in meditation and on several occasions have observed senior monastics who are believed to have attained the state of thukdam - including, most recently, a monk who remained in thukdam for 37 days at Gyuto Monastery in Sidhbari, near Dharamsala.
A forensic physician was invited to examine the body of the monk at various stages after death, the Office of His Holiness the Dalai Lama reported, emphasizing that the scientists had demonstrated that the body of a person in thukdam is in a different state from a body undergoing the ordinary process of death.
The Dalai Lama explained that in Tibetan Buddhism, it is believes the dying undergo a process of dissolution. Yet after some accomplished tantric meditators cease breathing, the process of dissolution offers three visions, during which 80 different conceptions dissolve - 33 during the first vision, 40 during the second, and seven during the final stage near attainment.
"When an ordinary person dies, there is a dissolution of the elements. Buddhists believe that beings go through past and future lives, so there is some bearing on this too," the Dalai Lama observed. "My own senior tutor, Ling Rinpoche, remained in thukdam for 13 days. Recently, a monk at Gyuto Monastery remained in this state for 37 days. This is an observable reality, which we need to be able to explain. There is evidence to see and measure. We can also find a detailed explanation of the inner subjective experience of the process of death in the Guhyasamaja Tantra texts. I hope scientists can take all this into account and come up with an explanation." (His Holiness the 14th Dalai Lama of Tibet)
The wide-ranging discussion encompassed a broad spectrum of related topics, among them the functioning of the brain during meditation, emotional and mental well-being, conditions for maintaining peace of mind, rebirth and memories of past lives, and the techniques and characteristics of various tantric meditation practices.
His Holiness noted that practitioners of thukdam should have be accomplished spiritual practitioners with a deep founding in the three principals of the Buddhist path: the determination to attain liberation, the awakening mind, and an understanding of the intrinsic emptiness of existence. They should also have cultivated a sound tantric practice and be well versed in the three visions and taking the three bodies during bardo.
"Rebirth involves consciousness. Consciousness consists of a continuity of moments of consciousness. Its nature is clarity and awareness," His Holiness explained. "The minds of all conscious creatures are like this. If we try to find a beginning to consciousness, we come up against the need for it to arise from a compatible cause - that is a previous consciousness. Therefore, we conclude that consciousness has no beginning because its source has to be a previous moment of consciousness.
"Although animals may have more acute sensory perceptions, human beings have sharper intelligence. However, it is mental consciousness that is crucial to both. We talk about past lives on the basis of the continuity of consciousness. Our subtlest consciousness has no beginning and no end. So, the mind goes on life after life until the attainment of buddhahood." (His Holiness the 14th Dalai Lama of Tibet)
Copyright © 2021 Buddhistdoor Limited (Buddhistdoor Global). All rights reserved.
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Российско-немецкая группа ученых предложила новый метод обнаружения раковых клеток с помощью магнитно-резонансной томографии. Для лучшей визуализации и большей контрастности изображения используются белки инкапсулины из бактерий рода Quasibacillus thermotolerans в сочетании с ферритином и ферроксидазой.
A Russian-German research team has come up with a new technique for magnetic resonance imaging of cancer cells. The study, published in Pharmaceutics, shows that heterologous expression of encapsulin systems from Quasibacillus thermotolerans with functional cargo proteins and iron transporter leads to increased contrast in MRI imaging of mammalian tumor cells.
Currently, the primary method of live-cell imaging is direct labeling of cells with a probe or contrast agent before transplantation. However, any synthetic contrast agent for cell labeling has a critical drawback - it dilutes as the cells divide, which leads to loss of the signal after several cycles of divisions. In contrast, genetically encoded reporters propagate to daughter cells with each cell division. Moreover, their signal is selective for viable cells.
Ferritin, a blood protein that contains iron, is the most studied genetically encoded agent so far. However, ferritin's MRI performance is limited by its weak magnetic properties and highly conservative structure.
"One of the most promising approaches is based on the heterologous expression of bacterial protein nanocompartments - encapsulins - in mammalian cells. Encapsulins can serve as genetically controlled labels for multimodal detection of cells. They can host various guest molecules inside their lumen. These include, for example, fluorescent proteins or enzymes with ferroxidase activity," says Maxim Abakumov, head of the NUST MISIS Biomedical Nanomaterials Laboratory, senior researcher at the Medicinal Nanobiotechnology Department, N.I. Pirogov Russian National Research Medical University.
A team of scientists from NUST MISIS, V. Serbsky National Medical, N.I. Pirogov Russian National Research Medical University, Technical University of Munich, Helmholtz Center Munich have implemented, for the first time, heterologous expression of encapsulin systems from Quasibacillus thermotolerans using a fluorescent reporter protein and ferroxidase in human hepatocellular carcinoma cells. Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA. The researchers loaded the nanoshell with the natural ferroxidase cargo from Q. thermotolerans and a synthetic fluorescent cargo protein derived from mScarlet-I. The successful expression of self-assembled encapsulin nanocompartments with functional cargo proteins was then confirmed by fluorescence microscopy and transmission electron microscopy. Also, coexpression of encapsulin nanoshells, ferroxidase cargo, and iron transporter led to an increase in contrast in magnetic resonance imaging of cancer cells.
Copyright © 2021 Cision US Inc.
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Исследователи Сибирского федерального университета и Института биофизики СО РАН упростили технологию обнаружения ядовитых веществ в продуктах питания, упаковав ферменты-индикаторы в оболочки из крахмального или желатинового геля. Это позволяет ферментам дольше сохранять нужные свойств независимо от условий хранения.
Scientists from the Siberian Federal University (SFU) and the Institute of Biophysics of the Siberian Branch of the Russian Academy of Sciences (IBP) have simplified the technology of searching for poisons in food.
The new technology makes it possible to extend the shelf life of enzymes-indicators of poisons by several times. In turn, this significantly reduces storage costs. Details of the new development have been published in Catalysts magazine.
Enzymes are proteins that act as catalysts in all living organisms. It should be noted that even a small amount of toxins significantly reduces the activity of enzymes. It is this property that scientists use when they need indicators to monitor the pollution of food and the environment - water, soil and air.
By observing the reaction of, for example, the enzyme butyrylcholinesterase with apple juice, scientists determine how much poisonous pesticides are contained in the sample, which enter the fruit from the soil.
Unfortunately, enzymes are extremely sensitive to storage conditions. The fact is that they are very easily destroyed due to temperature changes or, for example, humidity. This is why high quality laboratory analysis is not cheap.
A solution of natural polymers saves the enzyme from losing the desired properties. In such a "package" it can be stored for at least one and a half years without worrying about the conditions. Now laboratory enzymes "live" on average from several days to several months. The new method has no analogues in terms of simplicity and efficiency, the authors of the development note.
The finished product is dried "droplets" of gel with a dose of enzyme, they look like tiny circles of rice paper. Moreover, one analysis on laboratory equipment with such a drug will cost a maximum of 100 rubles.
Recall that a pesticide is a substance (or a mixture of substances) of chemical or biological origin, designed to destroy harmful insects, rodents, weeds, pathogens of plants and animals, and also used as a defoliant, desiccant and growth regulator.
Previously, pesticides were called pesticides.
Pesticides are used to destroy or stop the development of insects, ticks, mammals (rodents), bacteria, viruses, fungal spores, harmful vegetation and other living organisms that damage crop and livestock production and cause deterioration in the quality of agricultural products, materials and products. They are also used to combat parasitic organisms and vectors of dangerous human diseases.
As pesticides, chemicals have been used since the days of the most ancient civilizations: in Greece and Rome. In the Odyssey, in Canto 22, Homer uses the modern concept of fumigation (fumigation) in connection with the use of sulfur for treating buildings and the surrounding area, and calls sulfur "cleansing" (disinfection). 400 years BC. e. Democritus recommended spraying plants with a pure infusion of olives (olives) without salt to prevent rotting and insect damage. He also suggested treating the seeds with hare cabbage juice: this plant is rich in tannins and organic acids, which have a negative effect on pathogens.
Copyright © 2021.
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Госкорпорация «Росатом» приняла участие в международном проекте по борьбе с истреблением носорогов Rhisotope Project. Защищать животных планируется с помощью атомных технологий - в рог носорогов будут вводить безвредное количество радиоактивных изотопов, что, во-первых, сильно затруднит перевозку этих рогов благодаря устройствам обнаружения радиации в пунктах пересечения границ, а во-вторых, упростит обнаружение контрабанды. На первом этапе проекта, начавшемся 13 мая, ученые будут наблюдать за двумя первыми носорогами, получившими изотопы.
A new international project to use nuclear science-based techniques to drastically reduce rhinoceros poaching has been launched in South Africa. The Rhisotope Project was initiated by the University of Witwatersrand in collaboration with the Australian Nuclear Science and Technology Organisation, Colorado State University (USA), Russian nuclear company Rosatom and the Nuclear Energy Corporation of South Africa as well as global scientists, researchers, rhino owners and veterinary surgeon and rhino expert William Fowlds.
The project will investigate introducing harmless amounts of radioactive isotopes into the horn of a rhino with the aim of decreasing the demand for rhino horn on the international market as well as making it more detectable when crossing international borders.
"With over 10,000 radiation detection devices installed at various ports of entry across the globe, experts are confident that this project will make the transportation of horn incredibly difficult and will substantially increase the likelihood of identifying and arresting smugglers," Rosatom said.
The first phase of the project, which began on 13 May, saw trace amounts of harmless, stable isotopes introduced into the horns of two rhinos - named Igor, after Soviet nuclear physicist Igor Kurchatov, and Denver, after the state capital of Colorado - in the Buffalo Kloof Private Game Reserve. Igor and Denver will be monitored over the next three months to understand how the isotopes interact with the horn and the animal.
Once a proof of concept has been demonstrated, the technique will be offered to both state and private rhino owners on the African continent and globally. The intellectual property as well as training and assistance will be made freely available to conservation organisations who wish to use the process to protect animals against poaching.
According to the South African Department for Forestry, Fisheries and the Environment, 394 rhino were poached for their horn in South Africa during 2020. Trade in rhino horn is illegal and banned internationally, but illicit sales continue. At a price of about USD50,000 per kilogram, rhino horn is one of the most valuable substances on earth, the Rhisotope Project says, and its trade is linked with major black market crimes including weapons, drugs and human trafficking. South Africa is home to 90% of the world's rhino population, but from 2010 to 2019 over 9600 rhinos were killed in poaching attacks, but at the current rate of loss wild rhino will be extinct in less than 8 to 10 years.
The Rhisotope project is also working on community uplift and investment, education and rhino research.
James Larkin, director of the University of Witwatersrand's Radiation and Health Physics Unit at the in Johannesburg, said South Africa is one of the few countries where it is possible to see the so-called "big five" animals (lion, leopard, rhino, elephant and Cape buffalo). "We've got to work hard to maintain that … for the people's employment, for the benefit of everyone who lives and works around the game farm. You have to realise that you can shoot a rhino once, but if you shoot it with a camera, you can do it a hundred times, a thousand times and people will keep coming back to see these beautiful animals, that's jobs for a lot of people, that's growth of the economy," he said.
© 2021 World Nuclear Association.
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Вице-президент РАН Алексей Хохлов осудил внесенный в середине мая в Конгресс США законопроект, фактически запрещающий американским ученым участвовать в совместных с Россией проектах.
Vice President of the Russian Academy of Sciences, Alexei Khokhlov, on Wednesday denounced a bill submitted to the US Congress that bans American scientists from taking part in joint projects with Russia.
In mid-May, the US Senate Committee on Commerce, Science and Transportation voted to ban, too, federal funding for American scientists who take part in talent development programs sponsored by China, according to Science magazine.
With this measure, scientists from several countries, including Russia, are also barred from managing projects with subsidies financed through US federal funds.
Khokhlov pointed out that the bill stipulates that an American scientist who takes part in programs that support the scientific talent in China, Russia, Iran and North Korea will not receive subsidies in the United States.
He indicated that, if this measure is approved, it will also mean that American scientists will not be able to participate in Russia's mega-scholarship program.
The vice president of the Russian Academy of Sciences said that the possible inclusion of American researchers in a wider range of joint programs is also subject to a ban.
He warned that the bill has a retroactive nature. In other words, if a scientist received a Chinese or Russian subsidy in the past, he or she will not receive US subsidies, he added.
Copyright © 2016 Agencia Informativa Latinoamericana Prensa Latina.
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Le Figaro / 20 mai 2021
Les pays de l'Arctique réunis face à la montée des températures et des frictions Les huit pays riverains, dont les États-Unis et la Russie, se retrouvent à partir de jeudi, en Islande, pour parler, entre autres, du réchauffement climatique et de l'exploitation des ressources.
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20 мая в Рейкьявике состоялось очередное заседание Арктического совета, который проходит раз в два года и призван способствовать сотрудничеству приарктических стран в сфере экологии и устойчивого развития. Его постоянными членами являются США, Россия, Канада, Дания, Швеция, Финляндия, Норвегия и Исландия. Основными вопросами на повестке дня стали ускоряющееся потепление в регионе, условия для развития морского транспорта и эксплуатации ресурсов, будущее местного населения.
Les huit pays riverains de l'Arctique (États-Unis, Russie, Canada, Danemark, Suède, Finlande, Norvège et Islande) se réunissent jeudi 20 mai en Islande pour un Conseil aux vœux affichés de coopération pacifique, malgré les points de tensions entre puissances, Washington et Moscou en tête. Réchauffement climatique de plus en plus rapide dans la région, conditions de développement du transport maritime et de l'exploitation des ressources facilitées par le recul des glaces, avenir des populations locales sont à l'agenda des chefs de la diplomatie rassemblés à Reykjavik pour cette réunion qui a lieu tous les deux ans.
Avec la fin de la présidence de Donald Trump - qui avait agité la région en proposant de racheter le Groenland en 2019 et en multipliant les déclarations visant les ambitions russes et chinoises -, la nouvelle ligne donnée par son successeur Joe Biden est suivie de près. Et constitue un test pour ses relations avec Moscou. Autre grande puissance arctique, la Russie remplace jeudi l'Islande à la présidence tournante de ce forum censé favoriser le dialogue, alors que l'Arctique est devenu une zone de tensions géopolitiques croissantes, avec des manœuvres militaires à un niveau jamais vu depuis la fin de la Guerre froide.
Mercredi soir, le nouveau chef de la diplomatie américaine, Antony Blinken, a rencontré pour la première fois son homologue russe, le vétéran Sergueï Lavrov, dans un prélude à un possible sommet envisagé prochainement entre Joe Biden et Vladimir Poutine. «Si les dirigeants de la Russie et des États-Unis peuvent travailler en coopérant» face aux défis communs, «le monde sera plus sûr», a lancé le ministre américain, tout en prévenant que Washington répondrait en cas de comportement «agressif» de Moscou. «Nous sommes prêts à discuter de toutes les questions, sans exception, à condition que la discussion soit honnête», a répondu son homologue russe.
«L'administration Biden et l'administration Trump partagent une perspective: celle de dire que les États-Unis sont de retour en Arctique et sont leaders de la coopération arctique», analyse Mikaa Mered, spécialiste de l'Arctique à Sciences Po. «L'administration Trump le faisait surtout sur les enjeux liés à l'énergie et à la sécurité, l'administration Biden va se poser sur d'autres sujets comme le climat. Mais dans les deux cas la dynamique est la même: les États-Unis sont de retour», souligne l'expert.
Lors de la précédente réunion en 2019 en Finlande, le climatoscepticisme de l'administration Trump avait pour la première fois empêché une déclaration commune du Conseil, les États-Unis refusant d'y voir figurer le changement climatique. Centré sur la coopération entre pays et conçu pour éviter les sujets qui fâchent depuis sa création il y a 25 ans après la guerre froide, le Conseil de l'Arctique est pourtant généralement un forum consensuel, et l'adoption d'une déclaration commune est cette fois acquise.
Principal forum régional, il rassemble également le Canada, le Danemark - dont le Groenland est un territoire autonome - la Suède, la Finlande, la Norvège et l'Islande. Ainsi que six organisations représentant les peuples autochtones de l'Arctique et treize pays observateurs - dont la Chine, lancée depuis 2018 dans une stratégie d'État «quasi Arctique». Son mandat exclut explicitement la sécurité militaire et l'instance n'a pas de pouvoir juridique.
«Faire baisser les risques sur le plan militaire»
Le tour de chauffe du Conseil avait donné lieu à quelques passes d'armes: Sergueï Lavrov a martelé lundi que l'Arctique était une zone d'influence légitime de Moscou et dénoncé «l'offensive» occidentale dans la région, tandis qu'Antony Blinken l'a appelé à éviter ce genre de déclarations et critiqué les règles maritimes russes. Le secrétaire d'État américain, qui a pris le temps de s'entretenir en aparté avec chacun de ses homologues des sept autres pays membres, a affiché son souhait de «maintenir l'Arctique comme un espace de coopération pacifique» et affirmé que Washington voulait éviter sa «militarisation».
La Russie n'a cessé d'accroître son dispositif militaire dans l'Arctique ces dernières années, y rouvrant et modernisant plusieurs bases et aérodromes abandonnés depuis la fin de l'époque soviétique. Mais Sergueï Lavrov a également prôné la relance de rencontres régulières entre les chefs des états-majors de la zone afin de «faire baisser les risques sur le plan militaire». Des rencontres suspendues depuis 2014 et l'annexion de la Crimée par Moscou. «Il y a un lobbying très fort en cours à Washington pour dire qu'il faut retrouver un forum de discussion militaire», souligne Mikaa Mered.
Signe de l'intérêt confirmé de Washington même si la question d'un achat a été remise aux oubliettes, Antony Blinken se rendra après la réunion au Groenland pour boucler sa tournée entamée dimanche au Danemark.
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Российские ученые обнаружили у подковоносых летучих мышей, обитающих в пещерах Сочинского национального парка, два новых коронавируса, которые являются ближайшими родственниками SARS-CoV-2.
Horseshoe bats (Rhinolophus sp.) are known reservoirs of zoonotic coronaviruses (CoVs). Over the last twenty years, viruses thought to have originated from these bats have given rise to two severe acute respiratory syndrome (SARS) epidemic outbreaks in humans: SARS-CoV-1 in 2002/2003, which was limited mostly to Asia, and the currently globally circulating SARS-CoV-2, first identified in December 2019.
Several species of horseshoe bat are distributed across much of Eurasia and Northern Africa, and host a number of as yet unidentified SARS-like coronaviruses. As much of the world remains in the grip of the 2019 SARS-CoV-2 outbreak almost 18 months on, it is of great importance to identify and determine the prevalence of SARS-adjacent coronaviruses in horseshoe bat populations where future epidemics could arise from.
A group of Russian scientists, led by Dr. Sergey Alkhovsky of the Gamaleya Research Institute of Epidemiology and Microbiology, have identified two novel coronaviruses circulating in local Russian horseshoe bat populations. Their data provide critical insights into the genetic diversity of bat coronaviruses, as well as regional and temporal conditions that may encourage the spread of infection.
The preprint research paper is available to read on the bioRxiv server.
The study
Alkhovsky and colleagues collected 120 oral (saliva and buccal cells) and 77 fecal samples from five species of horseshoe bats. Viral residue was isolated and separated from animal particles and studied using a ‘maximum likelihood’ phylogenetic analysis.
Two novel coronaviruses belonging to the Betacoronavirus genus of CoVs (like SARS-CoV-1 and -2) were identified, named BtCoV/Khosta-1/Rh/Russia/2020 and BtCoV/Khosta-2/Rh/Russia/2020 (Khosta-1 and Khosta-2, for short).
Further genetic analysis showed that genome organization of these two coronaviruses had the most significant similarity with two SARS-like coronaviruses identified in Bulgarian and Kenyan horseshoe bat in 2008 and 2007, respectively. Unlike SARS-like coronaviruses in eastern Asia, these coronaviruses lack ORF8, a non-structural protein present in SARS-CoVs 1 and 2.
Khosta-1 is most closely related to the Bulgarian 2008 CoV, but otherwise also showed high similarity with SARS-CoV-2 and other Chinese-originated CoVs. Interestingly, however, Khosta-1 structural proteins are more similar to those found in the Kenyan 2007 CoV.
Khosta-2 was found to be generally less similar to other bat CoVs than Khosta-1 is. It holds roughly the same degree of similarity to Khosta-1 as it does to previously identified bat CoVs.
Khosta-1 was found mostly in greater horseshoe bats from Kolokolnaya cave, while Khosta-2 was found at lower rates but more geographically and taxonomically spread.
Conclusions
Due to their lack of the ORF8 gene, these two novel viruses appear to be putting together an image of a "western" lineage of SARS-like coronaviruses, different from the "eastern" lineages containing SARS-CoV and SARS-CoV-2.
The difference in the distribution of the two viruses, the authors suspect, might be due to the high population density of the Kolokolnaya cave-residing bats, or due to seasonal changes in virality.
The genetic diversity of these viruses continues to increase beyond previously known. Due to rapid mutation and genetic exchange between viruses, there is a constant influx of new viruses likely to arise regularly within circulating bat populations.
These types of studies help identify strains that may become variants of concern in the future. As of yet, the diversity, prevalence, host range, and threat level to humans have yet to be established. But as future studies of greater sample sizes are continued, these factors are surely soon to be determined.
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Phys.Org / May 20, 2021
Researchers flip the motion of electrons on ultrafast time scales without slowing them down
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Чтобы изменить направление движения объекта, его необходимо замедлить. Это правило не распространяется только на не имеющие массы фотоны, способные не только двигаться со скоростью света, но и резко менять направление.
Физикам из Университета Регенсбурга, Университета Марбурга, Института геологии и минералогии СО РАН, НГУ и Института физики полупроводников СО РАН удалось изменить направление движения электронов, не замедляя их. Ученые использовали новый тип топологических изоляторов, на поверхности которых электроны ведут себя как безмассовые частицы.
To change the direction of motion of a massive object, such as a car, it has to be slowed down and brought to a complete standstill first. Even the tiniest charge carriers in the universe, the electrons, follow this rule. For future ultrafast electronic components, however, it would be helpful to circumvent the electron's inertia. Photons, the quanta of light, show how this could work. Photons do not carry mass and can thus move at the highest possible velocity, the speed of light. For a change of direction, they do not need to slow down; when they are reflected from a mirror, for instance, they abruptly change their direction without a stopover. Such behavior is highly desirable for future electronics because the direction of currents could be switched infinitely swiftly and the clock rate of processors could be massively increased. Yet, photons do not carry electric charge, which is a prerequisite for electronic devices.
An international consortium of physicists from the University of Regensburg, the University of Marburg, and the Russian Academy of Sciences in Novosibirsk succeeded in flipping the motion of electrons on ultrafast time scales without slowing them down. In their study, they employed the new material class of topological insulators. On their surfaces, electrons behave like massless particles moving almost like light. To switch the direction of motion of those electrons as rapidly as possible, the researchers accelerated electrons with the oscillating carrier field of light - the fastest alternating field in nature controllable by mankind.
When the electrons abruptly reverse their direction of motion, they emit an ultrashort flash of light containing a broadband spectrum of colors like in a rainbow. There are strict rules on which colors get emitted: Generally, when electrons are accelerated by lightwaves only radiation is emitted, whose oscillation frequency is an integer multiple of the incident light's frequency, so-called high-order harmonic radiation. "By carefully adjusting the accelerating light field, we were able to break this rule. We managed to control the electrons' motion such that light of every imaginable color could be generated," explains Christoph Schmid, first author of the study.
In a careful analysis of the emitted radiation, the scientists found further unusual quantum properties of the electrons. It became apparent that the electrons on the surface of a topological insulator do not move in straight lines following the electric field of light but rather perform meandering trajectories through the solid. "Even for a theoretician, it is highly fascinating to see which phenomena quantum mechanics can produce if you only look a little closer," elucidates Dr. Jan Wilhelm, who successfully explained the experimental findings with a simulation he developed together with his colleagues in the Institute of Theoretical Physics at the University of Regensburg.
"These results do not only provide intriguing insights into the microscopic quantum nature of electrons; they also suggest topological insulators as a promising material class for future electronics and information processing," summarizes Prof. Dr. Rupert Huber, who led the experimental work in Regensburg. Such expectations perfectly follow the mission statement of the Collaborative Research Center SFB 1277, funded by the German Science Foundation. Within this network, experimental and theoretical physicists explore novel relativistic effects in condensed matter and test possibilities to implement their findings in future high-tech applications.
The new findings are reported in the upcoming issue of Nature.
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Ученые Санкт-Петербургского политехнического университета Петра Великого разработали методику для определения оптимального состава электродных материалов для твердотельных литий-ионных аккумуляторов.
Microelectronics is the application of electronics to very small, microscopic, and even molecular components and circuits to produce small but highly functional electronic devices and equipment. The development of such miniature devices - sensors, implantable devices, and Internet of Things (IoT) devices - requires establishing small and complex power sources with large cyclic capability and high energy density, such as solid-state lithium-ion batteries (SSLIB).
Expert says traditional technologies for the production of lithium-ion batteries have reached their limits. It is difficult to further reduce the size and control the shape of the power source any further in the required nano and micron dimensions. Researchers at St. Petersburg Polytechnic University (SPbPU) believe that the use of Atomic Layer Deposition technology can provide the creation of miniature solid-state lithium-ion batteries with complex shapes and high specific energy.
Studying the new nanoscale materials for electrodes of Solid-state lithium-ion batteries, the SPbPU research team has developed a method to determine the electrochemical capacity of each component of the "nickel-cobalt oxide" system. Transition metal oxides have a high capacity and relatively low costs, which is well suited for the development of lithium-ion battery cells. During the experiment, nanofilms obtained by atomic layer deposition (ALD) were used as anode materials and demonstrated a high charge capacity at high current densities.
"We obtained nickel-cobalt oxide materials in the wide range of compositions from nickel oxide to cobalt oxide and proposed a method to determine the contribution of the capacity of each of the electrochemically active components of the charge/discharge process. This multipurpose technique can be used to determine the best materials’ compositions for lithium-ion batteries," notes Dr. Maximov of High School of Materials Physics and Technologies, Institute of Mechanical Engineering, Materials and Transport SPbPU.
In the future, researchers plan to apply developments to create improved cathodes and solid electrolytes to produce a prototype of a thin-film lithium-ion battery for microelectronics. The project is being implemented with the support of the Russian Science Foundation.
© Copyright - Inceptive Mind.
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Ученые ФИЦ Биотехнологии РАН обнаружили в горящих подземных угольных пластах Кемеровской области микроорганизмы, способные не только существовать в экстремальных условиях, но и перерабатывать химические соединения, опасные для живых организмов. На основе таких микробов могут быть созданы новые технологии очистки воздуха и воды от вредных примесей.
Several groups of microorganisms were detected at the site of an underground coal fire in the Kemerovo region of Siberia, communicated this Thursday the Federal Center for Research Fundamentals of Biotechnology, of the Russian Academy of Sciences.
The microbes were found in two samples. One of them was collected on the surface, where the temperature was 58 ºC, and the second, at a depth of between 5 and 10 centimeters. The scientists then studied their chemical makeup and sequenced the genomes they contained.
In all, the biologists identified the genes of 15 groups of archaea and bacteria, the latter being much more numerous. This was unexpected for the scientists, since normally in extreme conditions archaea predominate.
The microorganisms detected benefit from underground fires. In particular, the most prevalent edge ‘Chloroflexi’, responsible for 39% and 56% of the genetic material found in the samples, you can take advantage of the reactions with carbon monoxide. Likewise, organisms that use methane or feed on other microbes were identified. Biologist Vitali Kadnikov, who led the project, highlighted the level of evolutionary adaptation of microbes: "Only highly adapted microorganisms can exist here. Not only do they have unique protection systems, but they can also receive energy in the course of chemical transformations of the substances that are available to them".
Promise of new technologies?
The scientist indicated that the study of terrestrial extremophiles would serve not only science but also economics.
"Our research is another step towards understanding how these relatively young ecosystems arose, what connections they have, and if we can use them. They are very similar to those that form around hot springs, but who knows, they may contain very specific organisms that allow the development of new ways to obtain valuable biotech products by using hydrogen and carbon monoxide generated during the gasification of coal, "said the researcher.
The study by Kadnikov and his colleagues in Moscow and Tomsk was published in the journal Microorganisms.
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Гендиректор ГНЦ «Вектор» Ринат Максютов сообщил, что ученые выявили уже более 13 тысяч мутаций нового коронавируса в России.
Russian scientists have already identified more than 13,000 coronavirus mutations, but most of them do not have any significant impact on the course of the pandemic, Rinat Maksyutov, the director of the Vector research center that developed the EpiVacCorona vaccine, said on Saturday.
"Since June 15, 2020, we have been continuously monitoring the genetic variability of the novel coronavirus. Every month, all Russian Federation regions send samples of viral isolates which are then subjected to genomic sequencing. To date, the joint efforts of all organizations in the country have already identified more than 7,000 complete genomes of the novel coronavirus. More than 13,000 mutations have already been identified from these Russian isolates," Maksyutov said at Russia-hosted science clinic New Knowledge. Russia likely has tens of thousands of coronavirus variants currently circulating across its territory, according to the official. He stressed, however, that the majority of these variants have little effect on the "epidemic process" and that variants with higher contagiousness will likely become progressively more commonplace in all populations in the future.
The mutations that cause greatest concern get studied more closely at Vector, Maksyutov said. "At the moment, 370 complete genomes have been identified in Russia for the British strain, 27 for the South African variant, and 10 for the Indian one," he added.
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Российские и американские биологи совместно отслеживают весенние перемещения белых медведей, тюленей и морских котиков в Арктике. Это позволит получить представление о распространении и численности популяций арктических млекопитающих.
Sea ice in the Arctic serves as a habitat for polar bears and their prey, ice seals. The ice doesn’t follow international boundaries, and monitoring the migration of these species requires access to both American and Russian waters. A collaboration between scientists from both countries is providing a clearer picture of the species, which remain subsistence staples to Arctic communities.
Irina Trukhanova is a wildlife biologist with North Pacific Wildlife Consulting. The group contracts with the National Oceanic and Atmospheric Administration and U.S. Fish and Wildlife Service. She says that polar bears and ice seals are loosely spread out across a vast Arctic, and it can be difficult to keep track of their movements and populations. "The only time that you can actually look at those species in their natural habitat is springtime," Trukhanova said.
That’s when the species travel on the sea ice in the Chukchi Sea. However, U.S. researchers are normally restricted to U.S. boundaries. Researcher Paul Conn with NOAA says that process can be limiting, since the polar bears travel between sea ice in both Russia and the United States. "The only ones that they collar are the ones that end up over near Kotzebue, so that is a knowledge gap," Conn said.
In order to survey polar bears and ice seals across the entire Chukchi Sea, U.S. researchers with NOAA and Fish and Wildlife partnered with Russian scientists. The result was a 2016 aerial survey that observed the species populations and movements.
Using a combination of infrared technology with photography and visual observations, the researchers were able to track distribution and abundance of the seals and polar bears. Conn says the results from the research give a more complete view of the Arctic mammals in the wider Arctic. "It does give us a sense for where bears are in the spring in April, and having done surveys for seals at the same, we can see how important the distribution of prey is for the distribution of bears," Conn said.
Moving forward, Trukhanova says that global warming will necessitate continuous research, as the Arctic warms faster than any other part of the world. That has led to diminishing sea ice for polar bears, and the ice seals they prey on.
"If it melts earlier, if the ice cover isn’t stable enough, then the survival rates for the pups, specifically for the ringed seal pups, become lower," Trukhanova said.
The Alaska Nannut Co-Management Council, an organization of tribes that subsist on polar bears, praised the collaboration. In a statement, Nannut Executive Director Katya Gray said QUOTE "…this effort is significant for its use of non-invasive methods to study polar bears, the importance of which our tribes and hunters are consistently raising." Trukhanova, who grew up in Russia and attended the University of St. Petersburg, said the data could not have been collected without collaboration. "We were working together," Trukhanova said. "We were planning the survey together, trying to make the methods compatible and make the results compatible so we could join forces and bring all the data to the table and get the robust joint results that we could use on both sides of the border."
While the governments of both countries have had a sometimes tense relationship in recent years, Conn says he was impressed with the scientific community’s good-natured approach. "You hear about Russia and us, and this antagonistic relationship, but when you actually get to the people it’s just amazing the amount of love they have for their science," Conn said.
Results from the joint survey on polar bears and ice seals were published in the scientific journal PLOS One, part of the open-access Public Library on Science.
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18 мая из Архангельска в Норвежское море вышла экспедиция Росгидромета, организованная для изучения остатков затонувшей в 1989 году атомной подводной лодки «Комсомолец». Ученым предстоит оценить уровень радиации в месте затопления и степень загрязнения окружающей среды. Предыдущая экспедиция, проведенная совместно Россией и Норвегией в 2019 году, показала, что радиационный фон вокруг корпуса подлодки немного увеличился.
Russian scientists have embarked on a mission to the Komsomolets, a Soviet nuclear submarine that sank 32 years ago during an onboard fire off Norway’s northern coast, killing 41, in a bid to determine whether the wreck presents threats to the undersea environment.
The scientists, from Rosgidromet, Russia’s state weather agency which also measures radiation, set sail from Arkhangelsk last week aboard the Professor Molchanov research vessels, reaching the accident site over the weekend, Russian media reported.
The voyage comes at a time of heightened concern over Soviet-era submarines that sank by accident, or were intentionally scuttled, in Arctic waters during the Cold War. Bellona has urged the eight-country Arctic Council, now convening under Russia’s two-year chairmanship, to address raising those subs, as well as dozens of other pieces of highly radioactive debris abandoned by the Soviet Navy at sea.
On Sunday, according to the Barents Observer, Russia’s foreign ministry issued an invitation to its Arctic Council counterparts to a conference scheduled for June 2022, where experts are expected to hash out next steps in retrieving that waste.
The Komsomolets - once the most advanced nuclear submarine in the Soviet Navy - was carrying two plutonium warheads when it went down on April 7, 1989. Those now lie at a depth of 1,680 meters with the rest of the sub’s wreckage and pose ongoing worries about radioactive leakage at the bottom of the Norwegian Sea.
But plutonim isn’t the only concern. The submarine’s reactor, loaded with nuclear fuel, produces other radioactive isotopes like cesium 137 and strontium 90.
Leakage from the wreck - though deeply submerged and unlikely to contaminate fish stocks - has been detected on previous missions Russia and Norway have undertaken since the Komsomolets went down. In 2019, a joint expedition launched by the two countries discovered the leakage directly around the submarine’s hull had increased slightly over levels measured in 1998 and 2007.
The current expedition will take more water samples and pluck up seabed sediments that the scientists will analyze once back in port, the Barents Observer reported, citing Rosgidromet. The mission is expected to return on June 5.
A Cold War Icon
The Komsomolets put to sea in 1984, at a time when the Cold War had grown especially chilly. Its Advanced automated systems allowed for the sub to be operated by a relatively small crew of 69.
But what the sub lacked in crewmembers it made up for in firepower and stealth. Designed to go deeper than any other submarine in the world, the Komsomolets’ titanium hull could largely evade American detection - spurring a frenzy of submarine development in the US.
Yet while the Komsomolets began as a clear a symbol of the Soviet Union’s military might, it came to be one of the first signs of its undoing. At the time of the sinking, Glasnost reforms under Mikhail Gorbachev had taken firm root - and a catastrophe the Soviet Navy might earlier have hushed up was front-page fare in popular Russian newspapers like Komsmolskaya Pravda and Sovietskaya Rossiya.
Disaster at Sea
The minute-by-minute details of the wreck, as related in a public account by the CIA, were harrowing. The disaster began at 11:03 on that April 7, while the Komsomolets was sailing at a depth of 386 meters, when, suddenly, high-pressure air hoses connected to the submarine’s ballast tank burst their seal.
The hoses, driven by a frenzy of spraying air, damaged an oil containment and sparked a flash fire in the submarine’s oxygen rich air. The expanding blaze tripped the reactor’s emergency shutdown and caused a loss of power in the submarine’s hydraulic system - leaving the sub immobile and powerless.
In order to surface from the depths, the captain was forced to blow the main ballast tanks. Struggling upward, the Komsomolets managed to send its first encoded SOS to headquarters by 11:14.
But surfacing did not save the vessel. Belowdecks, the fire spread through cableways, engulfing all the aft compartments and heating them to more than 1,000 degrees Celsius. The rubber coating around the hull designed to muffle detection began to melt off in strips.
The captain ordered all sailors not engaged in damage control topside. Those fighting to save the ship donned masks from the vessel’s emergency breathing system. But the loss of pressurized air from the aft compartment caused an influx of carbon monoxide into the masks, and many of the men dizzied and lost consciousness. Those that remained standing were then forced to fight the fire without masks in a cloud of smoke.
Soon, the vessel began to sink again. While much of the crew had evacuated to the deck, six, including the captain, remained below. By 16:30, they were forced to abandon their struggle to keep the sub aloft. The sub was taking on water and they attempted to flee the via the sub’s unique escape pod.
A flawed rescue
But the pod initially failed to bear them away. A flaw in the system kept it riveted to the submarine’s conning tower. Finally, an explosion rocked the vessel and shook the pod free, sending it hurtling upward to the surface. Once there, the hatch blew off. But only one sailor managed to escape. The capsule flooded in rough seas, and the other five crewmen aboard, including the captain, perished.
Despite the hours that passed after the initial distress call, the Soviet Navy limped through its rescue response, first dropping a number of rafts from the air. But those rafts turned out to be too few. One raft from the sub itself capsized. Another raft sank with the sub. A number of sailors clung to a larger raft, but soon the cold waters began to take their toll.
It finally took a fishing vessel to rescue the crewmen who remained. At 18:00, the Aleksandr Khloystsov arrived at the site of the accident and plucked 30 men out of the sea. But by that time, 39 had already perished of hypothermia in the cold Norwegian Sea. Three more later died of smoke inhalation.
The matter of the Komsomolets shook faith in an already ailing navy. Within two years of the accident, the Soviet Union would cease to be - leaving in its wake hundreds of derelict decommissioned nuclear submarines, and a host of other radioactive hazards dumped by the military.
Cleaning up the radioactive legacy
By 1994, the government in Moscow would reveal the scale of its irradiated legacy in the Arctic. The Soviet navy had scuttled hundreds of barrels of nuclear waste in the Kara Sea, along with old nuclear reactors, and, in one case, an entire nuclear submarine.
Within the framework of the Arctic Council, Russia is making a major effort to open up about this past. While raising the Komsomolets from its watery grave may never be possible, Moscow is aiming to retrieve other hazards that pose even more serious risks to the undersea environment.
Chief among these are the K-159 and the K-27, both of which were submerged while their reactors still contained their nuclear fuel. Also of concern, according Nuclear Safety Institute of the Russian Academy of Sciences, or IBRAE, are the nuclear reactor from the K-140 submarine, five reactor compartments from other nuclear submarines, as well as the screen assembly from the Lenin nuclear icebreaker.
It is these objects, IBRAE says, that contain 90 percent of the radioactivity of the 18,000 pieces of radioactive debris that Moscow has admitted to scuttling in the Arctic. The Russian government has set itself the priority of retrieving these objects from the depths by 2030. But Russian authorities and Bellona are clear that such a goal will require significant international cooperation from among the nations of the Arctic Council.
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Scientific American / May 25, 2021
Humans Could Live up to 150 Years, New Research Suggests A study counts blood cells and footsteps to predict a hard limit to our longevity.
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Ученые из России, США и Сингапура пришли к выводу, что максимальная продолжительность жизни человека не сможет превысить 150 лет даже в самых благоприятных условиях. Именно столько организм в состоянии сохранять способность к восстановлению жизненных функций и возвращению в устойчивое состояние после нарушений.
The chorus of the theme song for the movie Fame, performed by actress Irene Cara, includes the line "I’m gonna live forever." Cara was, of course, singing about the posthumous longevity that fame can confer. But a literal expression of this hubris resonates in some corners of the world - especially in the technology industry. In Silicon Valley, immortality is sometimes elevated to the status of a corporeal goal. Plenty of big names in big tech have sunk funding into ventures to solve the problem of death as if it were just an upgrade to your smartphone’s operating system.
Yet what if death simply cannot be hacked and longevity will always have a ceiling, no matter what we do? Researchers have now taken on the question of how long we can live if, by some combination of serendipity and genetics, we do not die from cancer, heart disease or getting hit by a bus. They report that when omitting things that usually kill us, our body’s capacity to restore equilibrium to its myriad structural and metabolic systems after disruptions still fades with time. And even if we make it through life with few stressors, this incremental decline sets the maximum life span for humans at somewhere between 120 and 150 years. In the end, if the obvious hazards do not take our lives, this fundamental loss of resilience will do so, the researchers conclude in findings published on May 25 in Nature Communications.
"They are asking the question of ‘What’s the longest life that could be lived by a human complex system if everything else went really well, and it’s in a stressor-free environment?’" says Heather Whitson, director of the Duke University Center for the Study of Aging and Human Development, who was not involved in the paper. The team’s results point to an underlying "pace of aging" that sets the limits on lifespan, she says.
For the study, Timothy Pyrkov, a researcher at a Singapore-based company called Gero, and his colleagues looked at this "pace of aging" in three large cohorts in the U.S., the U.K. and Russia. To evaluate deviations from stable health, they assessed changes in blood cell counts and the daily number of steps taken and analyzed them by age groups.
For both blood cell and step counts, the pattern was the same: as age increased, some factor beyond disease drove a predictable and incremental decline in the body’s ability to return blood cells or gait to a stable level after a disruption. When Pyrkov and his colleagues in Moscow and Buffalo, N.Y., used this predictable pace of decline to determine when resilience would disappear entirely, leading to death, they found a range of 120 to 150 years. (In 1997 Jeanne Calment, the oldest person on record to have ever lived, died in France at the age of 122.)
The researchers also found that with age, the body’s response to insults could increasingly range far from a stable normal, requiring more time for recovery. Whitson says that this result makes sense: A healthy young person can produce a rapid physiological response to adjust to fluctuations and restore a personal norm. But in an older person, she says, "everything is just a little bit dampened, a little slower to respond, and you can get overshoots," such as when an illness brings on big swings in blood pressure.
Measurements such as blood pressure and blood cell counts have a known healthy range, however, Whitson points out, whereas step counts are highly personal. The fact that Pyrkov and his colleagues chose a variable that is so different from blood counts and still discovered the same decline over time may suggest a real pace-of-aging factor in play across different domains.
Study co-author Peter Fedichev, who trained as a physicist and co-founded Gero, says that although most biologists would view blood cell counts and step counts as "pretty different," the fact that both sources "paint exactly the same future" suggests that this pace-of-aging component is real.
The authors pointed to social factors that reflect the findings. "We observed a steep turn at about the age of 35 to 40 years that was quite surprising," Pyrkov says. For example, he notes, this period is often a time when an athlete’s sports career ends, "an indication that something in physiology may really be changing at this age."
The desire to unlock the secrets of immortality has likely been around as long as humans’ awareness of death. But a long life span is not the same as a long health span, says S. Jay Olshansky, a professor of epidemiology and biostatistics at the University of Illinois at Chicago, who was not involved in the work. "The focus shouldn’t be on living longer but on living healthier longer," he says.
"Death is not the only thing that matters," Whitson says. "Other things, like quality of life, start mattering more and more as people experience the loss of them." The death modeled in this study, she says, "is the ultimate lingering death. And the question is: Can we extend life without also extending the proportion of time that people go through a frail state?"
The researchers’ "final conclusion is interesting to see," says Olshansky. He characterizes it as "Hey, guess what? Treating diseases in the long run is not going to have the effect that you might want it to have. These fundamental biological processes of aging are going to continue."
The idea of slowing down the aging process has drawn attention, not just from Silicon Valley types who dream about uploading their memories to computers but also from a cadre of researchers who view such interventions as a means to "compress morbidity" - to diminish illness and infirmity at the end of life to extend health span. The question of whether this will have any impact on the fundamental upper limits identified in the Nature Communications paper remains highly speculative. But some studies are being launched - testing the diabetes drug metformin, for example - with the goal of attenuating hallmark indicators of aging.
In this same vein, Fedichev and his team are not discouraged by their estimates of maximum human life span. His view is that their research marks the beginning of a longer journey. "Measuring something is the first step before producing an intervention," Fedichev says. As he puts it, the next steps, now that the team has measured this independent pace of aging, will be to find ways to "intercept the loss of resilience."
© 2021 Scientific American, A Division Of Springer Nature America, Inc.
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Insider / May 26, 2021
Russia plans to launch a nuclear-powered spacecraft that can travel from the moon to Jupiter
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В 2030 году Россия планирует запустить космический буксир «Зевс» с ядерным реактором, способным вырабатывать энергию в течение длительного времени. Предполагается, что в ходе одной миссии буксир последовательно доставит космические аппараты на орбиты Луны, Венеры и Юпитера.
Russia is planning to send a nuclear-powered spacecraft to the moon, then Venus, then Jupiter.
Roscosmos, Russia's federal space agency, announced Saturday that its "space tug" - the term for a spacecraft that transports astronauts or equipment from one orbit to another - is scheduled to launch on an interplanetary mission in 2030.
The spacecraft's energy module, named "Zeus," is designed to generate enough power to propel heavy cargo through deep space. It's essentially a mobile nuclear-power plant.
Several countries have their eyes on similar technology as a way to shorten trips in space. Right now, spacecraft rely on solar power or gravity to accelerate. But that means it could take more than three years for astronauts to conduct a round-trip visit to Mars. NASA estimates that a nuclear-powered spacecraft could shave a year off that timeline.
The US hopes to put a nuclear-power plant - a 10-kilowatt reactor integrated with a lunar lander - on the moon as early as 2027. So far, however, NASA has only sent one nuclear reactor to space, on a satellite in 1965. Other spacecraft, like the Mars Curiosity and Perseverance rovers, are also nuclear-powered, but they don't use a reactor.
Russia, meanwhile, has put more than 30 reactors in space. It's "Zeus" module would advance those efforts by using a 500-kilowatt nuclear reactor to propel itself from one planet to the next, according to Russian state news agency Sputnik.
The mission plan calls for the spacecraft to approach the moon first, then head toward Venus, where it can use the planet's gravity to shift directions toward its final destination, Jupiter. That would help conserve propellant.
The entire mission would last 50 months (a little over four years), according to Alexander Bloshenko, Roscosmos' executive director for long-term programs and science. During a presentation in Moscow on Saturday, Bloshenko said Roscosmos and the Russian Academy of Sciences are still working to calculate the flight's ballistics, or trajectory, as well as the amount of weight it can carry.
The mission may ultimately be a precursor to a new frontier of Russian spaceflight: Sputnik reported that Russia is designing a space station that uses the same nuclear-powered technology.
Nuclear energy has advantages over solar power in space
Most spacecraft get their energy from a few sources: the sun, batteries, or unstable atoms called radioisotopes.
NASA's Juno spacecraft at Jupiter, for instance, uses solar panels to generate electricity. Solar power can also be used to charge batteries in a spacecraft, but the energy source becomes less potent as a spacecraft gets farther from the sun. In other cases, lithium batteries can help power shorter missions on their own. The Huygens probe, for instance, used batteries to briefly land on Saturn's moon, Titan, in 2005.
NASA's twin Voyager spacecraft use radioisotopes (sometimes called "nuclear batteries") to survive the harsh environments of the outer solar system and interstellar space, but that's not the same as bringing a nuclear reactor on board.
Nuclear reactors offer several advantages: They can survive cold, dark regions of the solar system without requiring sunlight. They're also reliable for long periods of time - the "Zeus" nuclear reactor is designed to last 10 to 12 years. Plus, they can propel spacecraft to other planets in less time.
But nuclear power has its challenges, too. Only certain types of fuel, like highly enriched uranium, can withstand a reactor's extremely high temperatures - and they may not be the safe to use. In December, the US prohibited the use of highly enriched uranium to propel objects into space if a mission is possible with other nuclear fuel or non-nuclear power sources.
Russia is gearing up for a nuclear-powered space station
Russian engineers began developing the "Zeus" module in 2010 with the goal of sending it to orbit within two decades. They're on track to meet that mark.
Engineers started manufacturing and testing a prototype in 2018, Sputnik reported. Roscosmos also signed a contract last year worth 4.2 billion rubles ($57.5 million) that put Arsenal, a design company based in St. Petersburg, in charge of a preliminary design.
The technology could aid Russia's efforts to develop a new space station by 2025. The BBC reported last month that Russia plans to cut ties with the International Space Station - which it shares with the US, Japan, Europe, and Canada - that year.
Russia launched the ISS in partnership with the US in 1998. But Russian Deputy Prime Minister Yury Borisov told the state TV channel Russia 1 last month that the ISS's condition "leaves much to be desired." Indeed, the station has recently experienced air leaks and a breakdown of its oxygen-supply system.
NASA has cleared the ISS to fly until at least 2028, but the agency will likely deorbit the station in the next 10 to 15 years.
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Специалисты Южно-Уральского государственного университета, Института органической химии им. Н.Д.Зелинского РАН и Тихоокеанского института биоорганической химии им. Г.Б.Елякова ДВО РАН синтезировали шесть новых веществ на основе сероорганических соединений, которые можно будет использовать для создания эффективных противораковых препаратов.
New effective compounds, which can be endogenous donors of a signaling molecule - hydrogen sulfide in the body, were synthesized by SUSU scientists. Due to this property, the obtained compounds are potential drugs with a cancer-preventing effect. The research work was published in the Russian Chemical Bulletin (Q3).
Organosulfur compounds with anticancer, antibacterial, and antirheumatic properties have been studied for some years by scientists from South Ural State University and N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences. In the latest study, they attempted to search for new derivatives of 1,2-dithiol-3-thiones - compounds with various biological activities.
Several years ago, scientists proved that the 1,2-dithiol-3-thione fragment is an efficient endogenous donor of hydrogen sulfide in the body. It means that it can increase the gas content in human blood and tissues. One of the most studied hydrogen sulfide donors in the world is 5- (4-hydroxyphenyl) -3H-1,2-dithiol-3-thione.
Scientists have previously developed an effective method for producing the compound. In the last work, the researchers reflected the strategy of a fundamentally new way of introducing a dithiolthione fragment based on the previously synthesized 4,5-dichloro-1,2-dithiol-3-thione into hybrid molecules.
Scientists carried out the synthesis and proof of the structure of new compounds in the joint laboratory of SUSU and the Institute of Organic Chemistry of the Russian Academy of Sciences, with their colleagues from the Pacific Institute of Bioorganic Chemistry. They tested the efficacy in mouse epidermal cell models (JB6 Cl41 P +) and in soft agar human leukemia cell models. The study of cancer preventive (anticancer) activity was carried out at the Pacific Institute of Bioorganic Chemistry. The cooperation of groups working in various fields of science has become a distinctive feature of research.
As a result, the scientists synthesized six new acetylthioglycoside derivatives of 4-chloro-1,2-dithiol-3-thione. It has been established that all of them can be used as potential drugs with anti-cancer effects.
The research is fundamental. In the future, scientists intend to obtain other compounds, fragments of which can release two or even three endogenously produced signaling molecules of hydrogen sulfide, carbon monoxide, and nitric oxide. The findings can create a breakthrough in obtaining multipurpose drugs and are of interest to organizations specializing in cancer preventive therapy.
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