|Российская наука и мир|
(по материалам зарубежной электронной прессы)
UNC News / April 3, 2017
UNC-Chapel Hill, Russian scientists create biological shield against nerve gas, pesticides
Potential treatment could protect against sarin gas and VX before exposure.
Химики из Университета Северной Каролины и Московского государственного университета разработали новый способ нейтрализации воздействия на организм нервно-паралитических газов и похожих на них пестицидов. Так называемые нанозимы, полые биополимерные наночастицы, заполняются специальным ферментом, разрушающим молекулы газа. Нанооболочка же защищает от преждевременного разрушения сам фермент.
Scientists at the University of North Carolina at Chapel Hill and Moscow State University have created a new way to package and deliver a potent enzyme that can reverse - and even prevent - poisoning by pesticides and nerve gas, including sarin, which has been used worldwide as a chemical weapon and estimated to be 26 times more deadly than cyanide, and VX.
* * *
The team, led by UNC-Chapel Hill's Alexander "Sasha" Kabanov, Mescal S. Ferguson Distinguished Professor, figured out how to wrap the powerful enzyme, called organophosphorus hydrolase, in a tiny nanoparticle, which could be taken before, during or after exposure to organophosphate-based toxins.
"It could provide complete protection even if injected many hours before exposure to a lethal dose of toxin," said Kabanov, who is also director of the Center for Nanotechnology in Drug Delivery at the UNC Eshelman School of Pharmacy. "The enzyme is so effective that just one molecule of the enzyme can decompose several thousand of molecules of toxin every second, so the nanozyme appears to be effective at much lower doses than other potential treatments."
Currently, animals and humans can be treated only after exposure. If caught early, treatment is very effective at reversing symptoms but the knockdown on some of these toxins is so fast that there is not enough time to respond or the toxin's effects are not realized until treatment cannot reverse damage. For something like VX or sarin gas, it's a matter of seconds before victims can no longer treat themselves.
Working with mice, Kabanov and his team showed that the nanozymes circulated for at least 17 hours after a single injection, but they believe that time can be extended with more work. One approach would be to make the nano-packaging, which is currently 25 to 100 nanometers in diameter, even smaller. The smaller the packaging, the better it is to hide it from the body's immune system, which tends to see large molecules like the life-saving enzyme as a foreign invader to be attacked and cleared.
The drug atropine, in combination with pralidoxime, has been the first line of treatment for organophosphate poisoning since World War II. However, atropine and pralidoxime cannot be given in advance to protect against poisoning and introduces a big, sometimes lethal, shock to the body.
"Two milligrams of atropine is a typical starting dose to counter organophosphate poisoning and it will make your heart to nearly jump out of your chest," said Greene Shepherd, a specialist in clinical toxicology and emergency preparedness at the UNC Eshelman School of Pharmacy who was not involved in the research. "A healthy person could probably survive it, but having something that could be administered in advance of exposure would be a very big deal."
The team's discovery was published in the Journal of Controlled Release.
На проходящем 3-6 апреля в Колорадо-Спрингс 33-м Космическом симпозиуме глава «Роскосмоса» заявил, что Россия готова продолжать и расширять сотрудничество с партнерами из США, Евросоюза, Японии и Канады в использовании Международной космической станции (МКС) после завершения текущей программы в 2024 году.
COLORADO SPRINGS, Colo. (Reuters) - Russia is open to extending its partnership in the International Space Station with the United States, Europe, Japan and Canada beyond the currently planned end of the program in 2024, the head of the Russian space agency said on Tuesday.
"We are ready to discuss it," Igor Komarov, general director of the Russian space agency Roscosmos, told reporters at the U.S. Space Symposium in Colorado Springs, when asked if his country would consider a four-year extension.
The $100 billion science and engineering laboratory, orbiting 250 miles (400 km) above Earth, has been permanently staffed by rotating crews of astronauts and cosmonauts since November 2000.
The U.S. space agency, NASA, spends about $3 billion a year on the space station program, a level of funding that is endorsed by the Trump administration and Congress.
A U.S. House of Representatives committee that oversees NASA has begun looking at whether to extend the program beyond 2024, or use the money to speed up planned human space initiatives to the moon and Mars.
Komarov said many medical and technological issues remain to be resolved before humans travel beyond the station's orbit.
"I think that we need to prolong our cooperation in low-Earth orbit because we haven't resolved all the issues and problems that we face now," Komarov said.
The U.S.-Russian human space partnership has long endured despite the swirl of political tensions between the two countries. In 1975, for example, at the height of the Cold War, an American Apollo and Russian Soyuz capsule docked together in orbit.
"We appreciate that ... political problems do not touch this sphere," Komarov said.
Moscow has an alternative if relations with the United States sour. Russia last year unveiled a plan to detach some of its modules and use them to create a new, independent outpost in orbit.
"We adjusted and made some minor changes in our programs ... but it doesn't mean that we don't want to continue our cooperation," Komarov said. "We just want to be on the safe side and make sure we can continue our research."
The United States is dependent on Russia's propellant module to keep the station in orbit.
Copyright 2017 © U.S. News & World Report L.P.
* * *
Впервые за 20 лет Роскосмос направил на ежегодный Космический симпозиум в Колорадо-Спрингс внушительное представительство, а генеральный директор Роскосмоса в своем выступлении особо подчеркнул стремление к сотрудничеству. Взаимовыгодное партнерство стало основным принципом космических исследований с тех пор, как возобладала идея о том, что космос существует вне национализма и земных границ. Однако есть и менее идеалистичные причины космических устремлений: соперничество, пережитки националистических взглядов и, разумеется, деньги. Каковы мотивы Роскосмоса?
It's not unusual for space agencies to wax lyrical about how their work exploring all that lies beyond Earth's atmosphere is for the shared benefit of humankind. It's probably expected. So when, at a panel during the 33rd annual Space Symposium in Colorado Springs, the head of the Russian space agency says things like "How should we collaborate for the benefit of all of us to get the best result?" and "We need to find the way how can we do it together," nobody seems to question his motives.
* * *
Which maybe they should have, since that country's space agency, Roscosmos, hasn't sent significant representation to the symposium in over 20 years. During this panel, which included 14 other space-agency leaders, Roscosmos general director - a dark, handsome man named Igor Komarov - puts special emphasis his country's desire to collaborate with the fledgling space programs of emerging nations, like Vietnam and Venezuela. Komarov sticks to feel-good terms like "cooperate" and "collaborate" when he talks about international partnerships - which he and other Roscosmos reps do throughout the symposium. But his agency's motivation seems more about another C-word: customers. Last year, the Russian government restructured Roscosmos as a state-run corporation, and the cash-strapped organization is using these altruistic overtures to cultivate nascent space programs into new customers dependent on Russia's 60 years of orbital expertise.
Russia is, of course, not the only space organization looking to profit in the name of higher ideals - SpaceX can only reach Mars and save civilization if it launches a lot of satellites. And mutually beneficial partnerships have been key to space exploration since the fall of communism gave way to the idea that space exists beyond the borders and nationalism of Earth. But such idealism overlooks the endeavor's roots in the fertile soil of nationalist competition, the still-present remnants of that country-centricity, and something else: money.
Right now, Roscosmos isn't just chasing ideals: It's struggling to survive. "Their program is in a very fragile condition, despite what Komarov, et al., were saying in Colorado," says John Logsdon, founder and former director of the Space Policy Institute at George Washington University. He lists some Russian issues: recent budget cuts; problems with the Proton rocket; delays with their next-generation Angara rocket. "It's a program that's in trouble," Logsdon says.
Come fly with us
Space transcends borders in very pragmatic ways, in addition to the get-along ones. Roscosmos already partners with big space players like the US, Canada, and Europe, and with nascent programs like those in Vietnam and India. It is working with the European Space Agency on the ExoMars - an orbiter (which is fine), a lander (which is not), and a future rover (which is obscure). NASA charters Russian Soyuz rockets to hurl astronauts, science experiments, and plenty of other US space stuff into orbit. And cosmonauts and astronauts have floated side-by-side in the International Space Station for so long that they speak a hybrid language called Runglish.
Such collaborations arise partly from practicality. If you've listened to anyone knowledgeable talk about actually doing that, you've heard the tired phrase "space is hard." Also expensive. So when it comes to the hardest of that already hard stuff, sharing the technical and financial burdens is the only way to make it happen. "It's always natural for any country to say, 'I want my own indigenous capability on launch and satellite,'" says Steve Isakowitz, president of the Aerospace Corporation. "The reality always hits that we all don't print money, and so we don't have infinite resources."
And so countries work together. It's at once the best way to solve problems that affect multiple nations, like what to do about space debris, and the best way to spend less and still accomplish the same goal. But, spending less isn't the only path to financial success. Making more also helps a lot.
Soyuz want to make a deal?
What better place to announce that you'd like to collaborate with "emerging space nations" - future customers - than at a gathering where 30+ countries are there to hear it? These countries will need launches, hardware, and expertise - and perhaps, just perhaps, they also have natural or human resources that Russia does not.
At a Roscosmos-only press conference convened later in the symposium, Komarov explains what Roscosmos is - which is to say, not at all like NASA. It is a "state corporation:" An umbrella company owned by the government. That's new. The "Roscosmos State Corporation for Space Activities" took charge of the country's space program and regulations in January 2016. And this Roscosmos isn't just in charge of launching rockets and doing science. Its mission statement (printed right there on its website) puts it in the business of "placing orders for the development, manufacture and supply of space equipment and space infrastructure objects," "international space cooperation," and "setting the stage for the future use of results of space activities in the social and economic development of Russia."
Roscosmos has a near monopoly on the Russian space industry. It encompasses more than 60 companies and 250,000 people. And in the spirit of collaboration, it is using those resources to do new things, like develop technology, Earth observation capacity, and communications systems for Vietnam, Venezuela, Brazil, Mexico, and Chile. Oh, and they are helping those countries develop their own experts - and space policies. In other words, Russia - in "helping" - is also shaping not just how the international space industry shapes up but also how it functions politically.
There's no reason Roscosmos has to help. So what's their angle? When asked directly whether Roscosmos why it is putting so much effort on collaboration, Sergey Savelyev, who's in charge of the agency's international operations, comes clean. "These are prospective clients," he says to me. Then, he chuckles.
An orbital oligarchy
Put another way, if Russia helps new nations develop functional space agencies and aerospace industries, then, suddenly, those places have space needs (costs) where there were none before. And who will they turn to for those needs? And with whom will they share their bounty of resources, data, infrastructure? Russia, of course.
Space agencies don't usually say much about money-making or resource-gathering when they talk about partnerships. "For the good of humanity" sounds better. But it's not like Russia's customer focus, to use corporate speak, makes them unique. "They're kind of come-lately to the party," says Logsdon. "That's been key to the Chinese international space cooperation strategy for a number of years, to work with emerging countries." China doesn't so much want customers as, say, sources of raw material. And to that end, they've been working with Brazil for three decades. "They've also been targeting sub-Saharan Africa and other Latin American countries as potential partners for a number of years," says Logsdon.
There's no reason to shame Russia for its ambitions. On the other hand, if you are rooting for some other space agency - or space corporation - you might have other worries. For instance, will Russia's growing market capture cut into SpaceX's customer base?
Not necessarily. "Saying they want to do it doesn't mean they're going to do it," says Logdson. "First, they have to be successful in seeking new partners." They're experienced, sure, and they've got the goods. "But their hardware is not in very good condition; their industrial base is hurting," he continues. I don't see this as a threat to other space countries as much as it is a shift in direction for a program that's in a bit of trouble."
And that's a smart strategic move. Space may be hard - but it's a lot easier if you're flush.
Команда ученых из Сибири (Томский госуниверситет, ИГМ СО РАН, ИАиЭт СО РАН), Урала (Институт экологии растений и животных УрО РАН, Горный институт УрО РАН) и США (Университет штата Аризона) определили возраст найденных в пещерах Горного Алтая и Урала ископаемых останков дикобразов. Оказалось, что животные обитали в означенных местах 30-50 тыс. лет назад (причем уральские дикобразы оказались старше сибирских примерно на 10 тыс. лет) и вымерли с наступлением последнего ледникового максимума.
Результаты исследования опубликованы в журнале Quaternary Science Reviews.
A team of specialists that included scientists from Siberia, the Urals, and the University of Arizona conducted radiocarbon dating of the teeth and bones of ancient porcupines found in the caves of Gorny Altai and the Urals. They established that these thermophilic animals lived in these territories 30,000 to 40,000 years ago and died out with the onset of the Last Glacial Maximum.
"There have been no similar publications based on Russian material," says Yaroslav Kuzmin of TSU, one of the authors of the article. "The reason is that the finds of porcupines in Siberia are extremely rare. The samples with which we worked were discovered by the famous Siberian paleontologist Nikolai Ovodov in the 1980s in the Altai (Razboynichya Cave). Later, in the 1990s and early 2000s, bones and teeth that were preserved in several caves of Altai and the Urals were added to them."
All this time, the age of ancient porcupines remained unknown, because the method of dating available to scientists required a large quantity of material for analysis.
"This method was not suitable for us," says Yaroslav Kuzmin. "First, in this case, material invaluable from the point of view of history will be completely lost in the course of dating. Second, the maximum size of the remains of animals found was only a few centimeters, so we simply did not have enough materials for analysis. Unique finds were preserved only because they were lying in caves of limestone, often at a temperature of about zero degrees, that is, they were not exposed to such destructive factors as heat, wind, and rain."
Therefore, the researchers were only recently able to reconstruct the past and establish the age of ancient mammals. This happened thanks to the close scientific collaboration of scientists from Russia and the US. The University of Arizona conducted a direct radiocarbon dating of porcupine bones and teeth with an accelerator mass spectrometer. This method requires a minimum amount of material (less than the fingernail of the little finger) but is an accurate way to determine geological age.
The results of the study showed that the fossils of porcupines living in the area of the modern Urals are more than 40,000 years old. Their Siberian relatives were significantly younger, from about 30,000 to 40,000 years ago. In the area that is now Russia, porcupines lived during an interstadial period, between two glacial maxima. According to the authors of the article, about 27,000 years ago, the cooling began, which changed the situation in the Altai Mountains: Forests decreased, the temperature and precipitation decreased, and the area occupied by grasses and bushes and other foliage increased. The conditions became unsuitable for the habitation of thermophilic mammals, and as a result, the porcupines permanently disappeared from the region.
More information about the results of the research can be found in the journal Quaternary Science Reviews.
© Phys.org 2003-2017, Science X network.
* * *
Россия готова выстраивать «эффективное и полноценное» сотрудничество с Японией в области мирного использования ядерной энергии, заявил директор госкорпорации «Росатом» Алексей Лихачев во время рабочего визита в Японию 4-7 апреля.
Russia is ready to build "effective and full-scale" cooperation with Japan in the peaceful uses of nuclear energy to harness the innovations of Russian scientists, Alexey Likhachov, director-general of state nuclear corporation Rosatom said this week. Likhachov began a working visit to Japan on 4 April, where he said in an interview with the Japan Times that cooperation between the two countries was "becoming an urgent necessity".
Likhachov's visit follows his signing in December of a memorandum of cooperation in peaceful uses of atomic energy with two Japanese ministries. One key area of cooperation under the agreement is post-accident recovery at the damaged Fukushima Daiichi plant. Likhachov told the Japanese newspaper that Russia is interested in creating a framework for cooperation - scientifically, technologically and financially.
On Russian assistance in Japan's recovery from the consequences of the 2011 accident, Likhachov noted that the Mitsubishi Research Institute had last month selected two Rosatom subsidiaries, RosRAO and Tenex, to conduct a feasibility study on the creation of a an integrated high-sensitivity neutron detector. This technology will be necessary, he said, for the most accurate "search and identification" of nuclear fuel fragments at the Fukushima Daiichi plant.
Likhachov also noted that the memorandum signed on 16 December enables the two countries to consider the creation of a "unified Russian-Japanese platform" to explore the promotion of innovative nuclear technologies based on the knowledge and experience of nuclear power engineers in both countries. Among such technologies, Likhachov referred to developments in fast neutron reactors, in which he said independent experts rank Rosatom as the world leader. Only in Russia - at the Beloyarsk nuclear power plant - are industrial scale fast neutron reactors in operation, he said.
Beloyarsk 4 - the BN-800 fast neutron reactor - started operating at 100% power for the first time in August last year and officially started commercial operation in November. The 789 MWe reactor is fuelled by a mix of uranium and plutonium oxides (MOX) arranged to produce new fuel material as it burns. Its capacity exceeds that of the world's second most powerful fast reactor - the 560 MWe BN-600 Beloyarsk 3.
Likhachov said that, owing to the fact Japan's geography means it has no indigenous reserves of uranium, "the raw material base for supplying fuel to its own nuclear power plants is therefore a topical issue for Tokyo".
Fast neutron reactors operate within a closed nuclear fuel cycle, requiring less uranium and leading to significantly less radioactive waste, he said, adding that Japanese specialists may one day participate in the work of MBIR - the multipurpose sodium-cooled fast neutron research reactor that is under construction at the site of the Research Institute of Atomic Reactors at Dmitrovgrad, which is in Russia's Ulyanovsk region. AEM-Technology announced last month it had started the manufacture of the reactor pressure vessel for MBIR.
This is a 150 MWt, sodium-cooled fast reactor that will have a design life of up to 50 years. It will be a multi-loop research reactor capable of testing lead, lead-bismuth and gas coolants, and running on MOX fuel. NIIAR intends to set up on-site closed fuel cycle facilities for the MBIR, using pyrochemical reprocessing it has developed at pilot scale.
Rosatom has said the MBIR project will be open to foreign collaboration, in connection with the International Atomic Energy Agency's International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO).
© 2017 World Nuclear Association.
* * *
Скончался легендарный советский космонавт, дважды Герой Советского Союза Георгий Гречко. Инженер, доктор физико-математических наук, ведущий научный сотрудник Института физики атмосферы РАН, популяризатор науки и общественный деятель. Его вторая экспедиция на орбитальной станции «Салют-6» в 1977-1978 гг. оказалась на тот момент рекордной по продолжительности: Гречко и Юрий Романенко пробыли в космосе 96 суток и 10 часов.
Legendary Soviet cosmonaut Georgy Grechko died Saturday at the age 85, from a heart problem. A veteran of three spaceflights during the heydey of the Soviet space program, Grechko was also a skilled engineer and an avid popularizer of spaceflight.
* * *
Georgy Mikhailovich Grechko was born on May 25, 1931, in Leningrad, now St. Petersburg. He finished high school in 1949 and graduated with distinction from Leningrad Military Mechanical Institute (Voenmekh) in 1955, after which he was recruited to work in the Special Design Bureau 1 (OKB-1) outside Moscow, the cradle of the Soviet ballistic missile and space program led by Sergei Korolev. One of Grechko's early assignments was to calculate trajectories for what would become the world's first satellite, Sputnik 1.
In 1967, he successfully defended a dissertation on the landing system for the robotic lunar landers (he would later earn a doctorate in physics and mathematics). By then, though, Grechko had already made a dramatic career switch. He was selected as one of a group of civilian cosmonauts in March 1966, just as the moon race between the United States and the Soviet Union was approaching its climax. The Soviet lunar program was canceled shortly afterward, however, and it wasn't until 1975 that he finally made it into Earth orbit as the flight engineer on Soyuz 17.
During the 29-day mission, Grechko worked on the Salyut 4 space station along with commander Aleksei Gubarev.
On December 10, 1977, Grechko and Yuri Romanenko blasted off onboard Soyuz 26 spacecraft bound to the Salyut 6 space station. The crew celebrated a new year onboard the outpost, and returned home on March 16, 1978, after 96 days in space, beating a spaceflight duration record set by U.S. astronauts on the Skylab station in 1974.
In 1985, at the age of 54, Grechko began his third spaceflight onboard Soyuz T-14, which took him to the Salyut 7 orbiting lab for another extended stay. Altogether, on three expeditions to three different Soviet space stations, Grechko logged a total of nearly 135 days in space. For that he was twice named Hero of the Soviet Union, the highest official honor in the nation.
After his retirement from active cosmonaut service in 1986, Grechko stayed until 1986 at NPO Energia (now RKK Energia), the nation's prime developer of space vehicles. In May of the same year, he joined the Institute of Biosphere Physics within the Soviet Academy of Sciences, where he served as a cosmonaut researcher until March 1992.
Thanks to his outgoing personality and sense of humor, Grechko became one of the most recognizable faces of the Soviet space program, which isn't exactly known for its openness. He wrote many articles, participated in numerous public events and published a memoir titled Cosmonaut No. 34. In his candid recollection of the mission on Salyut 6, Grechko told about heated arguments with his commander Yuri Romanenko over the role of military officers and civilian engineers in human spaceflight. The discussion got tense enough that afterward the two crewmates went to different compartments of the station to sleep. In the morning, when Romanenko knocked on the hatch, Grechko answered, "Who's there?".
From 1979 until 1990, Grechko hosted a popular show on Soviet TV about science and futurism titled "This Fantastic World," which featured many guests, including the prolific Soviet sci-fi author Arkady Strugatsky.
Grechko will be buried in "Cosmonaut Alley" at the Troekurov cemetery in Moscow on April 11.
Журнал Bulletin of the Atomic Scientists продолжает цикл статей на основе книги Зигфрида Хекера (директор Лос-Аламосской национальной лаборатории в 1986-1997 г.) «Обреченные на сотрудничество» - о совместной работе российских и американских физиков-ядерщиков после падения «железного занавеса». О грандиозном совместном эксперименте Лос-Аламоса и ВНИИЭФ по изучению высокотемпературной сверхпроводимости в магнитном поле сверхвысокой частоты, проблеме нестабильности плутония и методах массово-параллельных вычислений.
The first Russian explosive device to land on US soil wasn't delivered by a Russian missile, as Americans feared might happen throughout the Cold War. It was delivered by FedEx. The device, an explosive magnetic flux compression generator, arrived at Los Alamos National Laboratory in late 1993, shipped from the Russian Federal Nuclear Center VNIIEF. It allowed Los Alamos and VNIIEF scientists to conduct a groundbreaking joint experiment to study high-temperature superconductivity in ultra-high magnetic fields.
The shared excitement and jubilation the scientists involved felt over successful experiments like this were testament to a profound shift. Less than two years after the dissolution of the Soviet Union and some 18 months after the remarkable and improbable exchange visits between Russian and American nuclear weapons lab directors, scientists from Los Alamos and VNIIEF were conducting experiments at each other's previously highly secret sites. Some of these scientists had helped design their country's hydrogen bombs. Now, they were focused on fundamental scientific discovery.
The Soviet nuclear weapons program was built on the shoulders of scientific giants - Yuli B. Khariton, Igor V. Kurchatov, Igor E. Tamm, Andrey D. Sakharov, Yakov B. Zeldovich, and many others - just as the American program was built on the shoulders of J. Robert Oppenheimer, Enrico Fermi, Hans Bethe, Edward Teller, John von Neumann, and many more. Unlike their American counterparts, though, Soviet weapons scientists labored in secrecy during the Cold War. When Soviet leader Mikhail Gorbachev lifted the Iron Curtain, curiosity about US research and a pent-up desire to cooperate internationally led them to reach out to the American nuclear weapons labs during the last three years of the USSR. They did so at international conferences and during first-time lab exchanges, long before Washington was prepared for such collaborations.
Scientific cooperation tapped into the most basic interest of scientists and engineers on both sides, namely, the desire to create new knowledge and technologies. Science is fundamentally an interactive, cooperative pursuit, which requires exposing the results of research to review and critique. As a participant in those early exchanges, I can say that the common language of science allowed us to more easily cross cultures and borders. The two sides' expertise and facilities proved enormously synergistic, resulting in remarkable progress in several areas of science that neither side alone could have produced for some time to come. We found science, unlike politics, to be a unifying force - one that allowed us to build trust through collaboration.
The pursuit of fusion. High-energy-density physics was the first - and over the years, most intense - area of cooperation between US and Russian nuclear labs. The field involves studying materials at high densities, extreme pressures, and high temperatures, such as those found in stars and the cores of giant planets. On Earth, these conditions are found in nuclear detonations, the basic physics of which were obviously of great interest to the scientists involved.
Working together, they used VNIIEF explosive magnetic flux compression generators in Russia, VNIIEF generators sent by FedEX from Russia to the United States and charged with US-supplied explosives, and stationary pulsed-power machines at Los Alamos to produce ultra-high electrical currents and magnetic fields that, in turn, produced a wide range of high-energy density environments. This technology provided the capability needed to pursue a unique approach to civilian nuclear fusion, which has tantalized the international physics community for decades with its potential to provide unlimited clean energy. Such energy densities also enabled the scientists to study materials strength under extreme conditions, material behavior under super-strong magnetic fields, and many other problems.
In fact, the initial Los Alamos interest in VNIIEF flux compression technology was stimulated by VNIIEF's approach to an emerging energy research area now called magnetized target fusion, as Los Alamos scientistsI.R. Lindemuth and R. R. Reinovsky and VNIIEF scientist S.F. Garanin write in Doomed to Cooperate. Magnetized target fusion is an approach to fusion that relies on intermediate fuel densities, between the more conventional magnetically confined fusion and inertially confined fusion.
High-energy-density physics is exciting science that helps attract talent, especially young recruits. It represents a non-military outlet for creative weapon scientists to solve big-world problems for the benefit of mankind. It allows scientists to create new knowledge, not just try to prevent potential new nuclear dangers. It also opened the door to cooperation by scientists with complementary skills. The Russian side excelled in the design of the explosive generators, the American side in instrumentation and diagnostics, allowing the partnership to go beyond what had been achieved before by either side alone. For example, in the mid-1990s VNIIEF scientists produced a world-record magnetic field of 28 million gauss, some 50 million times larger than the magnetic field at the earth's surface. Moreover, many of the joint high-field experiments were considered the best-instrumented ever. US-Russian collaborations on high-energy-density physics between 1993 and 2013 resulted in over 400 joint publications and presentations, and opened the door for joint work in other areas.
An enigmatic element. Plutonium science was similarly of great interest to both sides, yet direct collaboration was not established until the late 1990s because of the sensitivity of the subject. Some fundamental aspects of plutonium science were first presented by Americans and Soviets at the Geneva International Conferences on the Peaceful Uses of Atomic Energy in 1955 and 1958. However, the US and Russian results presented in these and subsequent meetings differed dramatically, and the differences were not resolved until we established direct lab-to-lab collaborations.
By the early 1990s, both sides had for decades attempted to understand plutonium, a complex metal that exhibits six solid crystallographic phases at ambient pressure. Its phases are notoriously unstable, affected by temperature, pressure, chemical additions, and time (the latter because of the radioactive decay of plutonium).With little provocation, the metal can change its density by as much as 25 percent. It can be as brittle as glass or as malleable as aluminum; it expands when it solidifies, and its freshly machined surface will tarnish in minutes. It challenges our understanding of chemical bonding in heavy element metals, compounds, and complexes. Indeed, plutonium is the most challenging element.
Several of my Russian counterparts and I have devoted much of our 50 years of scientific endeavor attempting to understand the properties of this enigmatic metal.American and Russian scientists had disagreed for 40 years on how to tame plutonium's notorious instability, when, in 1998, I began working with Lidia Timofeeva, the preeminent Russian plutonium metallurgist. The end of the Cold War enabled us to talk, challenge each other's views, and finally understand this element better. Our joint work demonstrated the validity of Russian research finding that a high-temperature phase of plutonium could be retained at room temperature, but not stabilized, by adding small amounts of gallium. (We published the results in a paper called "A Tale of Two Diagrams.") US-Russian collaboration at more than a dozen plutonium science workshops continued for 15 years.
Computing power. Computational methods for massively parallel computing became a third important topic of scientific collaboration. During the 1992 US lab directors' visit to Sarov, I was surprised by VNIIEF's computational capabilities. Soviet computers were known to be greatly inferior to US supercomputers, the most powerful of which resided at the Los Alamos and Lawrence Livermore laboratories. Yet their three-dimensional simulations of a representative ballistic impact problem were extraordinary. When I marveled at my counterparts' computing abilities, one of them explained, "since we don't have the computing power you have, we have to think harder" - and they did. More than one thousand specialists worked in VNIIEF's Mathematical Department, including some of the most gifted Russian mathematicians and computer scientists.
Because only low-performing, single-central processing unit (CPU) computers were available to Russia's scientific institutes, in the 1970s VNIIEF began to physically link CPUs and create parallel software algorithms that efficiently used multiple CPUs to greatly accelerate simulations for problems such as hydrodynamics, heat conduction, and radiation transport. They confirmed the efficiency of their parallelization strategies on computers with up to 10 CPUs, the most they could link at the time. They also developed analytical models for predicting the scaling efficiency to arbitrarily large numbers of processors.
During this time, the American labs were just beginning to transition their nuclear simulation codes from powerful single-CPU computers to the massively parallel computers that were becoming commercially available, a transition the Russian side had accomplished years earlier but with fewer and less powerful CPUs. Our collaborations gave Americans access to proven parallelizing algorithms, and gave Russians the ability to evaluate different analytical models for predicting the scaling efficiency to large numbers of processors. This same technology would later prove critical to both US and Russian programs for maintaining their arsenals after nuclear tests were banned.
Allowing the nuclear weapons scientists to move out of the shadow of Cold-War secrecy through scientific collaborations made us realize how much we were alike. It helped build trust, which had a powerful impact on enhancing nuclear security because it allowed us to extend our collaboration into sensitive subject areas, like the safety and security of nuclear weapons and materials. For the nuclear weapons scientists, the progression from science to security was a natural evolution, since we had practiced both from the beginning of our nation's nuclear programs. It also fulfilled our desire to apply our skills to enhance scientific progress.
Editor's note: This column is based on materials in Doomed to Cooperate: How American and Russian Scientists Joined Forces to Avert Some of the Greatest Post-Cold War Nuclear Dangers, published by the Los Alamos Historical Society's Bathtub Row Press in 2016.
Copyright © 2017 Bulletin of the Atomic Scientists. All Rights Reserved.
* * *
Коллектив российских ученых впервые описал взаимодействие между гиппокампом (парная структура в лимбической системе головного мозга, связанная с процессами запоминания и ориентации в пространстве) и другими важными областями человеческого мозга. Оказалось, что правый и левый гиппокампы работают асимметрично - левый более активно взаимодействует с остальными структурами мозга, зато правый получает более полную информацию о пространственном окружении.
Having applied new neurocognitive and mathematical approaches, a group of Russian scientists has described an interaction between the hippocampus and other important areas of human brain for the first time. The results of work have been published in the journal Frontiers in Human Neuroscience.
Scientists have researched processes of memory and spatial orientation in the hippocampus, a conjugated structure in the medial crotaphic cerebral hemispheric region.
The researchers studied effective connections between the left and right hippocampal regions of the human brain with main structures of the default mode network, active during the conscious resting state. The default mode network includes the medial prefrontal cortex (MPFC), posterior cingulate cortex (PCC), and the inferior parietal cortex of the left (LIPC) and right (RIPC) hemispheres.
30 healthy subjects took part in the research (10 males and 20 females), all right-handed, aged 20 to 35 years. In the resting state, the researchers recorded functional magnetic resonance tomography (FMRT) of the subjects. To calculate effective relationships, they applied spectral dynamic causal modeling (DCM). The main idea of this method is to evaluate the parameters of a biologically based model of brain neural network interaction so that it best predicts the FMRT data observed in the experiment.
Scientists conducted three DCM analyses, verifying predictions of about 3,000 quantitative models. The first two analyses identified interactions between areas that included four key structures of the passive brain network in addition to the left and right hippocampus. The third analysis was a virtual neurosurgical experiment to determine the potential consequences of removal of one of the key structures of the human brain.
The study of effective (cause-effect) connections of the human hippocampus to other important structures of the brain was carried out for the first time. "We found evidence of a pronounced asymmetry in the work of the left and right hippocampus, which was completely unknown from previous studies conducted on animals. In general, the left hippocampus is more active than the right, interacting with the other brain structures. Apparently, this is due to the fact that speech mechanisms in humans (in 97% of right-handers and 75% of left-handers) are localized in the left hemisphere. But the right hippocampus has its advantage: It receives information from both intermodal centers, LIPC and RIPC, which serves as the basis for a holistic view of the environment. The left hippocampus, on the other hand, receives information only from the LIPC, so its knowledge about the environment is limited to the right half-space," said project manager Boris Velichkovsky.
"An analysis of effective connections allows us to determine the architecture of neural networks," said Vadim Ushakov, senior research fellow at the Cybernetics Department of the ICIS MEPhI.
He noted that such asymmetry of effective hippocampal connections explains one of the most frequent disorders of consciousness caused by local brain lesions, namely, left-sided space hemineglect in patients with lesions of the right hemisphere. A patient with this condition will, for instance, ignore food located on the left side of the plate at meal times, or, preparing for medical examination, shaves only the right half of their face. As a rule, traumas of the left hemisphere do not lead to similar loss of perception of the right half.
According to Vadim Ushakov, the study allows for a more holistic understanding of the work of the neural networks of the brain in order to provide a basic level of consciousness. In medical practice this serves as a good help for an accurate diagnosis of the functionality of the brain.
© Copyright 2016 The Washington Times, LLC.
* * *
Hominidés / 19/04/17
Une nouvelle Vénus russe de 23 000 an
C'est sur le site de Khotylyovo-2 dans la région de Bryansk (ouest de la Russie) que la statuette a été exhumée.
При раскопках стоянки «Хотылево-2» в Брянской области археологи обнаружили вырезанную из бивня мамонта фигурку возрастом примерно 23 000 лет. Такие характерные изображения женщин времен каменного века называют «Венерами палеолита»
La découverte n'a pas été annoncée dans une revue scientifique, mais sur le site The Siberian Times qui avait déjà publié en 2016 un article sur une autre Vénus préhistorique trouvée elle en Sibérie.
Le site de Khotylyovo-2
Les archéologues effectuent des fouilles sur le site de Khotylyovo-2 depuis 1993. Les scientifiques ont trouvé de de grandes quantités d'ossements de mammouths et de bisons ainsi que de nombreux outils en silex. Khotylyovo-2 était donc probablement un campement utilisé par des tribus de chasseurs-cueilleurs. Les datations radiocarbone montrent que le site était occupé entre 21 000 et 24 000 ans en arrière.
La vénus de Khotylyovo
La statuette a été trouvée à proximité de dépôts calcaires et d'ossements de mammouth dont certains étaient recouverts de terre de sienne, un colorant minéral naturel. Selon le Dr Konstantin Gavrilov (Département d'Archéologie Paléolithique, Institut d'Archéologie de Moscou), responsable de cette campagne de fouille, il apparait que «très probablement, la statuette a été placée à côté des ossements sur le sol plutôt que «enterrée» comme les autres «Vénus».
La statuette, qui mesure 5 cm de hauteur, a été sculptée dans l'ivoire d'une défense de mammouth laineux. D'un point de vue fabrication ce sont les mêmes techniques qui ont été employées que pour les autres Vénus de Russie. Aucune trace de ce qui aurait pu être un anneau ou un orifice pour suspendre la statuette.
Une forte poitrine, un ventre prononcé, un derrière proéminent mais des jambes relativement fines distinguent cette nouvelle statuette des Vénus découvertes précédemment. Même si une partie de l'ivoire a disparu, les proportions de la Vénus montrent que le « modèle » était assez grasse.
Le scientifique indique «Cette statuette représente une femme corpulente, mais elle a l'air fantastiquement délicate, probablement en raison de ses jambes longues et minces. La figurine avec ses jambes légèrement repliées sous le corps rappelle Danaé (mère de Persée dans la mythologie grecque), peinte par Rembrandt».
Danaé, la statuette de Khotylyovo est nue et on ne remarque aucun ornement sur le corps (bijoux, coiffe, pagne…). Ce type de statuette a déjà été exhumé en Sibérie, notamment près de la rivière Angara (à proximité du lac Baïkal) mais les dernières études montrent qu'elles sont généralement vêtues contrairement à ce qu'indiquaient les premières études.
Des interprétations libres…
L'article reprend une déclaration du Dr Gavrilov indiquant que la statuette pourrait représenter un «culte de la fertilité», mais rajoute que cette interprétation est impossible du fait que l'agriculture n'était pas encore développée.
L'article présente également l'hypothèse que cette femme corpulente était enceinte tout en précisant tout de suite qu'une partie du buste et du ventre sont manquants du fait de l'effritement de l'ivoire le long d'une fissure naturelle de la défense.
© Hominidés.com - 2002-2017 - Tous droits réservés.
* * *
Chemical & Engineering News / April 19, 2017
Chemists can now be picky about organosulfur compounds
A new strategy enables direct selective C-H functionalization of a single sulfur component from mixtures typical of petroleum refinery streams.
Соединения серы активно используются в различных отраслях науки и промышленности. Доступный их источник - серосодержащие примеси в нефти, но способы их выделения слишком многоступенчаты, дорогостоящи и предполагают большое количество отходов. В Институте органической химии им. Н.Д.Зелинского РАН разработали простой способ селективной C-H функционализации с ацетатом палладия в качестве катализатора, позволяющий выделять отдельные компоненты в смеси сероорганических соединений.
When hearing someone describe the typical preparation of organosulfur compounds, it's clear the approach is not a very sustainable one. Mixtures of sulfur compounds naturally in crude oil are first treated with hydrogen in a catalytic refinery process to remove the sulfur - the goal is to pull out as much sulfur as possible to create cleaner transportation fuels. The hydrogen sulfide that forms in this hydrodesulfurization step is converted to elemental sulfur. Chemists then pair this sulfur with selected reactants to reconstruct desired organosulfur compounds one product at a time. Overall, the energy-intensive multistep process is costly and generates a significant amount of waste.
A new strategy reported by Valentine P. Ananikov of the Russian Academy of Sciences' Zelinsky Institute of Organic Chemistry and coworkers enables unprecedented direct C-H functionalization and separation of only one sulfur component at a time from mixtures of organosulfur compounds (ACS Omega 2017, DOI: 10.1021/acsomega.7b00137).
"Ananikov and coworkers describe an unexpected and striking selectivity for organosulfur compounds," says Lanny S. Liebeskind, an organosulfur catalytic functionalization expert at Emory University. "While not yet directly applicable to the processing of fossil fuels, this very interesting study suggests at least conceptually a possible future approach to the value-added desulfurization of petroleum."
The Russian researchers use palladium acetate along with oxygen and silver trifluoroacetate as a combination oxidant to couple an olefin, such as ethyl acrylate, to an aryl or heteroaryl sulfur compound. The reaction's selectivity centers on the sulfur acting as a directing group to guide the C-H activation and alkenylation. Benzyl compounds provide the most favorable geometry for palladium binding, followed by phenylethyl compounds and then longer alkyl chains, which leads to exclusive functionalization of one component at a time in mixtures concocted to simulate refinery streams.
"Ananikov's team has discovered a straightforward route to organosulfur compounds by using the cheapest palladium catalyst to mediate alkenylation of multicomponent mixtures of the sulfur compounds abundant in crude oil," says Mario Pagliaro of Italy's National Research Council, who specializes in green chemical processing of natural resources. "This is groundbreaking work that will change the way organosulfur compounds are produced from the current, poorly sustainable approach."
Copyright © 2017 American Chemical Society.
* * *
По данным ЮНЕСКО, в России 41% женщин участвуют в научных исследованиях. Это заметно выше среднемирового уровня (29%), хотя и не самый высокий показатель по отдельным странам. Кроме того, согласно новому исследованию Microsoft, в России девочки раньше начинают интересоваться точными науками и продолжают ими увлекаться дольше.
Irina Khoroshko, from Zelenograd near Moscow, had learned her times tables by the age of five. Her precocious talent, encouraged by a maths-mad family and a favourite female teacher who transformed every lesson into one giant problem-solving game, led to a degree in mathematical economics at Plekhanov Russian University of Economics.
"My lecturer instilled in me the power of numbers and calculation, how it gives you the ability to predict things; in that sense the subject always felt magical," she says. Now Irina, 26, is a data scientist at Russian online lender, ID Finance, enjoying a lucrative career devising analytical models to determine loan eligibility.
And this isn't an unusual story in Russia. But it is in many other countries around the world.
Several studies confirm that all too often girls' early interest in Stem subjects - science, technology, engineering and maths - fizzles out and never recovers. So relatively few women go on to choose engineering or technology as a career. Why? A new study from Microsoft sheds some light.
Based on interviews with 11,500 girls and young women across Europe, it finds their interest in these subjects drops dramatically at 15, with gender stereotypes, few female role models, peer pressure and a lack of encouragement from parents and teachers largely to blame.
Not so in Russia.
According to Unesco, 29% of people in scientific research worldwide are women, compared with 41% in Russia. In the UK, about 4% of inventors are women, whereas the figure is 15% in Russia. Russian girls view Stem far more positively, with their interest starting earlier and lasting longer, says Julian Lambertin, managing director at KRC Research, the firm that oversaw the Microsoft interviews.
"Most of the girls we talked to from other countries had a slightly playful approach to Stem, whereas in Russia, even the very youngest were extremely focused on the fact that their future employment opportunities were more likely to be rooted in Stem subjects." These girls cite parental encouragement and female role models as key, as well as female teachers who outnumber their male colleagues presiding over a curriculum viewed as gender neutral.
The differences don't stop there.
When the Department for Education asked a cross-section of British teenagers for their views on maths and physics, five words summed up the subjects' image problem: male, equations, boring, formulaic, irrelevant. But no such stigma exists in Russia, says Mr Lambertin. "They've really gone beyond that," he says. "People are expected to perform well in these subjects regardless of gender."
Alina Bezuglova is head of the Russia chapter of Tech London Advocates, an organisation that connects Russian talent with job opportunities in the UK. She regularly hosts women-only tech events in the UK, but not so in Russia. Why?
"You could say it's because we are neglecting the problem or that there is no problem at all, and I'm far more inclined to think the latter," she says. "Compared to the rest of Europe, we just don't stress about 'women's issues'."
According to Ms Bezuglova, Russian women's foothold in science and technology can in part be traced back to the Soviet era, when the advancement of science was made a national priority. Along with the growth in specialist research institutes, technical education was made available to everyone and women were encouraged to pursue careers in this field.
"It never occurred to me at school that because I'm a girl I shouldn't be choosing Stem, and in the workplace I don't see much sexism, only that you're judged on your abilities," she says.
But could the national psyche also play a part?
With their characteristically forthright nature, do Russian women simply find it easier to speak up for themselves in male-dominated environments?
Emeli Dral, assistant professor at the Moscow Institute of Physics and Technology, thinks so. She recalls how it was precisely this spirit that spurred her on to success as one of only two girls in her advanced maths group at school.
"It actually made both of us even more competitive and more determined to prove ourselves and be better than the boys," she says. "I think Russian women are pretty confident about being in a minority, mainly because of the support they have had from their parents from a young age. Mine never queried why I was interested in maths and engineering - it was considered to be very natural."
Olga Reznikova, whose largely self-taught approach to Stem led to her current role as a senior software engineer, is a case in point. Growing up in a small seaside town populated by miners and fishermen, her love of computers began when she was just four, but it was a struggle to turn her passion into a career. Turning to online tutorials, she mastered the basics of algorithm design, machine learning and programming and made money coding simple websites. But wary of a future stuck in "IT outsourcing sweatshops", she headed to St Petersburg to study further and land a bigger role.
"For a while I was the only female programmer at my company," she says. "I did encounter some issues with being taken seriously, but I stayed with it and am now earning a salary that's 30% higher than before."
While Russia is doing something right, it's still not there yet in terms of gender parity.
"There is no doubt that Russia is firing up girls' imaginations," says Mr Lambertin. "Bringing creativity to the classroom with hands-on, practical application, and stressing the relevance of these subjects by focusing on the workplace, could be the way forward for those countries where girls are currently very disengaged."
Copyright © 2017 BBC.
* * *
Международная группа российских, бразильских и японских ученых объяснила механизм свечения в темноте некоторых видов грибов.
Dozens of glow-in-the-dark mushroom species grow around the world. But details on what makes them shine so bright have long been dim.
In a new study, scientists say they can finally explain what makes bioluminescent mushrooms glow. They describe a process of "enzyme promiscuity" that leads to changes in the intensity and colors of mushrooms' light emissions.
The researchers, who hail from Russia, Brazil, and Japan, published their findings Wednesday in the journal Science Advances.
Bioluminescence exists in a wide range of organisms, including deep sea fish, fireflies, and glowworms. In March, another group of scientists found the first solid evidence of fluorescence in amphibians, courtesy of the South American tree frog. Of around 100,000 fungal species, about 80 are known to be bioluminescent. Some of these emit a green light from within to attract beetles, flies, wasps, and ants, which in turn help disperse the mushrooms' spores and spread the fungi across the forest canopy, a 2015 study found.
Zinaida Kaskova and her colleagues analyzed the extracts of two such 'shrooms for their study: Neonothopanus gardneri, a fluorescent mushroom native to Brazil, and Neonothopanus nambi, a poisonous mushroom found in the rainforests of southern Vietnam. In most cases of bioluminescence, living organisms emit light when a molecule called "luciferin" - from the Latin lucifer, which means light-bringer (also, Satan?) - combines with its enzyme partner "luciferase." When luciferin and luciferase mix together with energy and atmospheric oxygen, it triggers a chemical reaction. The result is a very "excited" oxyluciferin, which releases light energy in order to "calm down" to its lowest energy state, the scientists explained.
Previous research has characterized the luciferin-luciferase combination in bioluminescent insects, bacteria, and marine mammals. But Wednesday's study is the first to describe this in fungi. Kaskova, a researcher at the Russian Academy of Sciences' Institute of Bioorganic Chemistry, said she and her team were able to pinpoint the structure of oxyluciferin in fungi. They found that fungal luciferase may be "promiscuous," in that it can potentially interact with multiple derivatives of the luciferin molecule in mushrooms.
Their findings could pave the way for scientists to harness bioluminescence in mushrooms. Scientists already use fluorescent molecules to track cells and proteins in biological research. This could add another tool for analytical and imaging technologies.
© 2005-2017 Mashable, Inc. All Rights Reserved.
* * *