Российская наука и мир (дайджест) - Октябрь 1999 г.

Дайджест за другие годы
1999 г.
Российская наука и мир
(по материалам зарубежной электронной прессы)

    Nature / Volume 401,No 6754, p.628 14 October 1999
    Aim for better business sense to bolster Russian science

Росийская Академия наук учредила новую организацию под названием Сверхбюджетный Фонд, целью которого являетя создание собственных средств и каналов их получения для поддержки ученых и их научных работ. "Мы надеемся, что с помощью этого фонда наши библиотеки смогут сделать подписку на основные журналы, появится возможность финансировать наши экспедиции и решить наиболее острые финансовые проблемы", - сказал Г. Месяц, вице-президент академии.

MOSCOW The Russian Academy of Science (RAS) has set up a new body, known as the Above-Budget Foundation (ABF), to manage its property and channel the income it receives to supporting scientists and their work.
According to Gennady Mesyats, the academy's vice-president responsible for ABF activities, the new body has already generated more than $1 million in income, even though it started operating only a few months ago.
"Next year we hope to get $3 million, and in the coming years ABF plans to operate with tens of millions of dollars," says Mesyats. "We hope that this will enable our libraries to subscribe to all major journals, and that we can finance expeditions, and solve our most acute financial problems." Mesyats told a meeting of the academy's praesidium in Moscow last week that, for the first time in recent years, the government has this year transferred all the money it had allotted to science both on time and in full. But the praesidium emphasized that the total amount being made available is still insufficient to meet the needs of Russian science. External income is therefore very important, Mesyats emphasized, particularly given that the budget money can only be used for specified purposes, such as salaries, and cannot be redistributed. The academy owns considerable property, which until recently has been inefficiently used. It has 38 buildings in Moscow alone, and many stores, hotels and other real estate around the country. The academy also receives income from its scientific ships, and substantial revenue is raised through its international academic association 'Science', which manufactures and distributes copies of scientific exhibits. The academy also makes money from publishing. More than 80 scientific journals are published in English by a recently founded publishing company, Nauka, which is expected to raise $1 million next year, partly because publication of the two leading Russian physics journals was transferred to it from the American Institute of Physics.
The ways in which these funds are to be spent are discussed at weekly meetings of the RAS praesidium, chaired by Yuri Osipov, the academy's president. This year's priorities have included buying apartments for young scientists, providing petrol supplies for mountain observatories and supporting scientists' widows.
"Finding external funds is a new activity for us, even though in other countries it is quite normal; up to 30 per cent of the income of US universities comes from using their property, such as stadiums, parking places and living quarters," says Mesyats.

© Macmillan Publishers Ltd

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    Science News / Vol. 156, No. 14, October 2, 1999, p. 216.
    The Strangest Home on Earth
    Looking for frosty life in a lake under Antarctica
    • Richard Monastersky

Половина континета практически неизученной территории покрыто толстым слоем льда и так надежно спрятано, что ученые почти не не имеют представление о нем. Только три года назад российские и британские гляциологи обнаружили огромное озеро - одно из самых больших и глубоких - скрытого под слоем льда, достигающего толщины 4000 метров. Отрезанное от всего мира в течение миллионов лет, озеро Восток может дать убежище для древних видов микроорганизмов, неизвестных науке, которые способны выжить в таких экстремальных условиях. Изучение озера - прекрасная возможность изучить нашу планету, ее историю. Возможно, условия жизни миллионы лет назад на Земле были аналогичны условиям жизни на других планетах.

A flight over the eastern portion of Antarctica crosses territory so monotonous it could lull an insomniac into unshakable slumber. For thousands of kilometers in all directions, a thick sheet of ice coats every bit of real estate, even the tips of the tallest peaks. Hour after hour, varying shades of white pass beneath the plane, with no hint of any other hue. Beneath the boring white blanket lies half a continent of virtually uncharted territory—a terra nova so completely hidden that scientists have little clue what riches await discovery. Only 3 years ago, Russian and British glaciologists identified an immense lake—one of Earth's largest and deepest—buried beneath 4,000 meters of ice immediately below Russia's Vostok Station (SN: 6/29/96, p. 407).
When the team announced the find, many other researchers sniffed that the lake was little more than a curiosity, says glaciologist Martin Siegert of the University of Bristol in England, one of the lake's discoverers. As more details have emerged, however, a growing number of scientists have picked up the scent, with dozens of investigators now panting to explore the feature, known as Lake Vostok. "This is a very exciting opportunity to learn about our planet, the history of our planet, perhaps even analogues to life on other planets," says David Karl, a microbiologist at the University of Hawaii at Manoa in Honolulu who cochaired a conference last fall on Lake Vostok. "It was pretty amazing how uniform the interest is," he says. Cut off from the rest of Earth for a million years or more, Lake Vostok may harbor ancient species of microbes, unknown to science, that are able to withstand conditions at the edge of survivability. Moreover, a thick layer of sediment at the bottom of the lake could hold novel clues to the planet's climate going back tens of millions of years. The mysterious body of water inspires even otherworldly interest: NASA hopes to use the lake to test methods for detecting life on other planets.
In August, the National Science Foundation—which runs U.S. operations in Antarctica—decided that it would fund an airborne survey of the lake, a first step toward eventually drilling into the water. This week, some 60 scientists gathered in Cambridge, England, to start planning an international expedition to explore the lake and capture samples of its residents, if any exist. Along with the potential rewards come a host of challenges. Researchers must find a way to penetrate the icy covering without introducing any microorganisms or pollutants into the sealed-off water. "We know absolutely nothing about subglacial lakes. If we're going to work on them, we must assume that we are going to take extreme measures to avoid any sort of contamination," says Cynan Ellis-Evans of the British Antarctic Survey in Cambridge, who led this week's meeting. Vostok Station holds the uncomfortable distinction of having recorded the coldest temperature on Earth. Thermometers there measured -89.6°C in July 1983, and the average temperature hovers down around -55°C.
It's the thick ice, strangely, that enables a lake to survive in such a frozen environment. "The 3 kilometers or so of ice acts effectively as an insulating blanket that protects the bedrock underneath the ice from the cold temperatures above," says Siegert.Geothermal heat coming from the planet's interior keeps the lake from freezing and warms the lowest layers of ice. The tremendous weight of the ice sheet also plays a role in maintaining the lake. Beneath 4 km of glacier, the pressure is intense enough to melt ice at a temperature of -4°C.
These factors have helped lakes develop across much of the thickly blanketed East Antarctica. To date, Siegert and his colleagues have detected more than 70 hidden lakes in the small portion of the continent they've examined so far.
Lake Vostok is the largest of these, stretching 280 km from south to north and some 60 km from east to west, roughly the size of Lake Ontario but twice as deep. At the station, which sits at the southern end of the lake, the water depth appears to be 500 m, according to seismic experiments carried out by Russian researchers.
The first clues to Lake Vostok's existence came in the 1970s, when British, U.S., and Danish researchers collected radar observations by flying over this region. The radar penetrates the ice and bounces off whatever sits below. When researchers found a surface as flat as a mirror, they surmised that a lake must exist underneath the ice. Gordon de Q. Robin of the University of Cambridge reported the subglacial water, but the data didn't reveal whether there was a single giant lake or several separate ones. It took a view from space to define the lake better. Using radar data collected by ERS-1 satellite measurements, J.K. Ridley of University College London found that ice was much smoother and flatter above the lake than it was above the surrounding mountainous regions. In 1993, he charted the northern end of the lake, but the available data did not resolve the southern portion near Vostok Station. Three years later, Siegert analyzed an improved set of satellite radar data without ever setting foot on the Antarctic continent. Along with Robin, Ridley, and other researchers, Siegert fully mapped out the dimensions of the lake using the satellite, radar, and seismic measurements.
Only then—some 20 years after it was first suspected—did the lake start to garner attention outside the narrow field of glaciology. When Nature splashed the news of Vostok on its cover in 1996, biologists started wondering whether the buried lake could harbor exotic new species. At the time that people first found hints of Lake Vostok, there was little reason to suspect it might harbor any life. "The most exciting advance since the 1970s is the understanding that life on this planet can occur, and indeed thrive, in extremely difficult environments," Siegert says.
If microbes do populate the lake, they may be some of the hungriest organisms ever discovered. "Lake Vostok has the potential to be one of the most energy-limited, or oligotropic, environments on the planet," says microbiologist Edward F. DeLong of the Monterey Bay Aquarium Research Institute in Moss Landing, Calif.
For the lake's residents, the only hope for a sizable meal would come from below. Russian investigators have speculated that the lake floor has hot springs spewing out hydrothermal fluids stocked with reduced metals and other sorts of chemical nutrients. They base their argument on the shape of the lake. Its elongated outline and substantial depth resemble Lake Baikal in Siberia, which sits in a geologically active rift zone. At this site, Earth's outer shell is pulling apart, allowing molten rock to rise close to the surface and feed hydrothermal springs.
Geologists, however, have always painted the exact opposite picture of East Antarctica. The scant geological evidence available for this region indicates that the crust is old and dead.
Without a stream of nutrients seeping up from the deep Earth, the only potential source of energy lies above the lake. The ice sheet above the water is creeping from west to east at a rate of roughly 4 m per year. The lowermost layers of ice melt when they come in contact with the lake, liberating trapped gases and bits of crushed-up rock.
Indirect evidence for this glacially slow delivery system comes from drilling operations at Vostok Station, where Russian and French researchers have pulled up cylindrical ice samples—about as wide as a coffee can—of ice down to within 120 m of the lake surface. In January 1998, the team ceased its work to prevent contaminating the lake with the diesel fuel used to lubricate the drill. In the lowest part of the hole, the scientists found a 200-m-thick layer of ice containing giant crystals. This and other properties indicate that the ice formed as the lake water froze to the bottom of the glacier.
Researchers suspect that the bottommost ice melts as it passes over the western edge of the lake and then water freezes onto the ice sheet as it moves over the eastern portion of the lake underlying Vostok Station.
What comes out of the melting ice is guesswork at the moment because geologists know so little about East Antarctica. If the glacier recently passed over sedimentary rock before reaching the lake, it could be supplying organic compounds useful to microorganisms. It also could be seeding the lake with a continuous source of new residents. S.S. Abyzov of the Russian Academy of Sciences in Moscow has found bacteria, yeasts, fungi, algae, and even pollen grains in the Vostok ice core down to depths of 2,750 m -three-quarters of the way to the bottom. At least some of these organisms are alive and capable of growing, he reported last year.
Karl is currently examining ice from the 3,600-meter depth for signs of viable microbes. Because ice from that depth formed from frozen lake water, it contains a sample of whatever was floating at the surface of the lake. The results from this analysis may indirectly indicate whether anything survives in the lightless body of water.
If denizens of Lake Vostok don't succumb for lack of food, they could easily suffocate. Because of the intense weight bearing down from the ice sheet above—340 times atmospheric pressure—the water contains almost no dissolved oxygen, carbon dioxide, methane, or other gases.
According to calculations, gas molecules should reside in crystal cages of ice, forming a structure called a clathrate. Some of these may create a slushy zone floating at the top of the lake, while others could sink to the floor.
Despite the apparent odds against life, biologists place their bets on the bacteria. "I would be surprised if there were no microbes in Vostok rather than the other way around," says Karl.
What excites researchers is the idea that resources in the lake are not evenly distributed. Microorganisms, just like any business, tend to exploit inequalities in supply and demand. By living on the border between two environments, cells can extract energy as materials move from regions of plenty to paucity. For instance, bacteria may well thrive on the surface of the clathrates, taking advantage of a gradient in methane concentrations.
Clathrates have also captured the attention of climate scientists because they may contain ancient samples of oxygen and other gases, says glaciologist Todd A. Sowers of Pennsylvania State University in State College. The frozen cages of gas could have built up on the lake bottom, layer by layer, over a million years or more. By looking at the ratio of different oxygen isotopes in these clathrates, scientists should be able to trace how Earth's temperature has changed since the time that some of the earliest humans were spreading across the world.
Below the clathrate layers, Lake Vostok apparently holds vast sedimentary deposits chronicling tens of millions of years of Antarctic geology. The Russian seismic experiments indicate that sedimentary layers extend hundreds of meters below the lake floor. In many ways, however, the bottom of Lake Vostok is even more remote than the surface of Mars.To study the lake's sediments, scientists need to drill through the ice, sterilize the probe before entering the lake, pass the instrument through hundreds of meters of lake water, bore into the sediments below, then pull the samples back up through the ice. All this at crushing pressures. The constraints steer engineers in opposite directions, says Joan Horvath, a project manager at NASA's Jet Propulsion Laboratory in Pasadena, who's developing plans for Lake Vostok. "To get anything through the ice, you want it to be small," she says. "However, once you get a submersible down there, it's very difficult to get something small that will operate at high pressure. In that environment, you like things to have thick walls. So, there is an inherent engineering mismatch between the two things you're trying to do." Most concepts for a first Vostok mission don't involve collecting samples. A simpler plan calls for melting a hole through the ice and then sending a robotic submersible into the lake to analyze the water and search for hydrothermal vents. The hole would refreeze almost instantly, so the trapped instrument would send back information via a cable running up through the ice.
NASA has expressed interest in Lake Vostok because of its similarity to Europa. This moon of Jupiter appears to have a water ocean covered by a thick ice sheet, measuring perhaps tens of kilometers in depth. If hydrothermal vents roil away beneath the ice, chemical reactions on Europa could have created the molecular building blocks for life, if not life itself (see p. 219 and SN: 11/7/98, p. 296).
Vostok would be an ideal testing ground for technology that would eventually fly to Europa or places even more distant, say many scientists. "If we want to be able to search for life on other planets, this [Vostok mission] would be a drop in the bucket," says Sowers.
Though cheap compared with a Europan mission, any expedition to Vostok would represent a significant investment. Participants at the meeting this week in Cambridge discussed ways to harness support from many nations for a mission.
Researchers also debated whether it makes sense to focus on Lake Vostok to the exclusion of other ice-covered Antarctic lakes. "I'm not convinced at all that Vostok is the best place to drill," says Siegert. Part of the problem is Vostok Station. U.S. officials are reluctant to use the aging outpost because of environmental and safety hazards there, so any expedition would have to set up a camp elsewhere on the lake. According to Siegert, "it may be sensible to drill down into a subglacial lake [that] is located quite close to a serviceable station. And also one that's relatively small so that if it's spoiled in some way, it won't be the best example of a subglacial lake."
Siegert and others have pointed out that a lake lies almost directly beneath the station run by the United States at the South Pole. Because of the facilities already there, a drilling operation near the South Pole would cost less than at the remote Vostok site. Yet the size of Lake Vostok gives it some unique advantages. Shallower lakes may have frozen in the past few hundred thousand years, during spells when the ice sheet was thinner, says Robin Bell, a geophysicist at Columbia University's Lamont-Doherty Earth Observatory in Palisades, N.Y.
"Since Vostok is so deep, it's very unlikely that it has frozen solid since the ice sheet was built," says Bell, who cochaired last November's Vostok workshop at the National Science Foundation.
The agency recently decided to fund Bell's proposal to complete an airborne survey of Lake Vostok, which will help answer whether Earth's crust is currently tearing apart there. Bell views the agency's action as a symbol of its growing interest in sampling the lake. She says, "This isn't going to guarantee that they're going to go the whole way, but without this they weren't going to do anything."
Future missions depend in part on what Bell finds in the next 2 years while flying a gridlike pattern of traverses over the endless white expanse near Vostok Station. Despite the blankness of the surface ice, though, the geophysicist will have little trouble staying awake as her instruments plumb the depths of the alien lake below.

© 1999, Science Service

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    Nature / Volume 401, No6755, p. 736. 21 October 1999
    Russian institute challenged over seized fossils

    Грузовик, груженый ископаемыми остатками и задержанный на таможне на российско-финской границы в декабре прошлого года, содержал по мнению российских специалистов-палеонтологов, много образцов, представляющих научный интерес, например, ранее нигде не описанные виды медведей. Министерство культуры выдало лицензию, т.к. первоначально директора института палеонтологии РАН говорили, что образцы не имеют научной ценности.

[MUNICH] — A lorry-load of fossils seized by customs officials at the Russian-Finnish border last December has been found by Russian palaeontological experts to contain many scientifically valuable samples, including two previously undescribed species of bear . (Nature 397, 189; 1999)
Many of the items had originally been described by the directors of the Russian Academy of Sciences' Institute of Palaeontology (PIN) as having no scientific value, so the ministry of culture had issued export licences. The items will now be offered to Russian museums, and government officials have stripped the PIN of its formal advisory role to the ministry.

Nature © Macmillan Publishers Ltd. 1999

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    Sciencedaily Magazine / 5 October 1999
    Element 107 May Soon Find Place On Chemists' Periodic Table
    107 элемент скоро найдет свое место в Периодической таблице Менделеева

    Source: Lawrence Berkeley National Laboratory (http://www.lbl.gov)

BERKELEY, CA — An international collaboration of radiochemists has used the PHILIPS cyclotron at the Paul Scherrer Institute (PSI) in Bern, Switzerland, to determine the volatility of bohrium, element 107 — the heaviest element yet whose chemistry has been successfully investigated. Crucial to the research was the use of an isotope of bohrium with a relatively long half-life of about 15 seconds, detected earlier this year by researchers at the U.S. Department of Energy's Lawrence Berkeley National Laboratory and the University of California at Berkeley. The team worked at Berkeley Lab's 88-Inch Cyclotron with visitors from the PSI and the University of Bern. Although several elements heavier than bohrium have been identified, including the discovery within the past year of elements 118 and 116 at the 88-Inch Cyclotron and element 114 at the Flerov Laboratory of Nuclear Reactions in Dubna, Russia, the correct placement of the heaviest elements in the periodic table is under study.
"In the discovery experiments of new elements, only the existence of a new, very heavy atomic nucleus is demonstrated," says Heinz Gдggeler, leader of the PSI team, "but no information about its chemical properties is obtained." To date, the heaviest element whose chemical properties have been widely investigated by experiment is seaborgium, element 106. "Thus, in the view of a chemist," Gдggeler says, "the periodic table currently ends at seaborgium." "Elements beyond 100 are made an atom at a time, with very low production rates, and have very short half lives," says Darleane C. Hoffman, a longtime collaborator with Gдggeler's team and coleader of the group which identified the relatively long-lived isotope, bohrium 267, at the 88-Inch Cyclotron. A member of the Nuclear Science Division at Berkeley Lab, she is a professor of chemistry at UC Berkeley. Hoffman says, "The chemistry of the heavy elements requires separations that come to equilibrium very rapidly, and these must be valid on an atom-by-atom basis." Such atoms are created in the laboratory by bombarding heavy target nuclei with an accelerated beam of projectile ions. The nuclei of interest, which are created by the evaporation of a few neutrons, are only a very small fraction of the huge number of reaction products produced. At PSI, the PHILIPS cyclotron yielded about three atoms of bohrium during a day of beam time, but only four bohrium nuclei were detected in the first two weeks of the volatility experiment. The PSI researchers used a beam of neon 22 to bombard a target of berkelium 249, which has a half-life of 320 days. The targets were prepared at Berkeley Lab from material furnished by the Department of Energy through its Transplutonium Element Production Program at Oak Ridge National Laboratory. Immediately after bombardment, the reaction products were swept into an automated isothermal system called the On-Line Automated Gas Analyzer (OLGA) developed by Gдggeler and his colleagues. There, reaction products formed molecules in oxygen-containing hydrogen chloride gas. These oxychlorides were then passed through a chromatography column, in which the more volatile species pass through at lower temperatures. In this system, bohrium 267 compound was shown to be volatile at 180 degrees Celsius. The four bohrium atoms were found only after they had passed through the chromatography column, when the oxychloride molecules containing them were deposited on a rotating detector that carried each small sample under a set of radiation detectors. Bohrium 267 was unambiguously identified by the pattern of its alpha decay, first to dubnium 263, then to lawrencium 259, and subsequently to mendelevium 255. Because the positive charge of a heavy nucleus is so great, the electronic structure of the atom is distorted. These so-called "relativistic effects" can produce unexpected deviations from chemical properties extrapolated from the element's lighter homologues in the periodic table. Bohrium may also prove to deviate in this way. The oxychloride of bohrium was shown to be volatile at 180 C, similar to its lighter homologues in group VII of the periodic table, such as rhenium and technetium. Continuing experiments will determine whether bohrium is also volatile at lower temperatures. Technetium, for example, is volatile at 50 C and rhenium at 75 C under the same conditions. The need to develop techniques for understanding the chemistry of the heaviest elements is partly driven by the search for the "island of stability," a group of superheavy elements whose nuclear shell structure is predicted to make them stable for hundreds or thousands of years or longer, instead of for mere seconds or milliseconds. Isotopes with the number of neutrons required to reach the island of stability have not yet been created.
Meanwhile, however, there is a region of relative stability due to "deformed shells" at lower neutron and proton numbers, which includes bohrium 267. Thus chemical studies of bohrium are not only intrinsically interesting, but aid in what Darleane Hoffman calls "the long march up the periodic table toward the island of stability." Besides Hoffman, the collaborating team at Berkeley included Berkeley Lab senior scientists Kenneth Gregorich and Heino Nitsche, who is also a professor of chemistry at UC Berkeley, postdoctoral fellows Uwe Kirbach and Carola Laue, and graduate students Joshua Patin, Dan Strellis, and Philip Wilk.
In addition to PSI, Berkeley Lab, and UC Berkeley, collaborating institutions included the University of Bern in Switzerland, the Flerov Laboratory in Russia, the Forschungzentrum Rossendorf, Gesellschaft fьr Schwerionenforschung (GSI), and Technical University of Dresden in Germany, and the Japan Atomic Energy Research Institute in Japan.
The Berkeley Lab is a U.S. Department of Energy national laboratory located in Berkeley, California. It conducts unclassified scientific research and is managed by the University of California.
Editor's Note: The original news release can be found at http://www.lbl.gov/Science-Articles/Archive/element-107-chem.html

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    Nature / Volume 401. No 6755, p. 736. 21 October 1999
Mobil buys into Russia's oil production know-how

    The Mobil Technology Company подписала соглашение на 330 тысяч долларов со Всероссийским институтом теоретической физики в Снежинске и двумя институтами РАН . Соглашение предусматривает разработку сложных математических методов оптимизации добычи нефти.

MOSCOW. The Mobil Technology Company has signed a US$330,000 agreement with the All-Russian Institute for Theoretical Physics (VNIITF) in Snezhinsk -- the nuclear city formerly known as Chelyabinsk -- and two institutes of the Russian Academy of Sciences. The agreement addresses the modelling of oil flow in porous media, and will provide Mobil with sophisticated mathematical techniques for optimizing oil production.
The agreement brings one of the earliest investments in VNIITF by a commercial organization, and the institute's first investment through the Partner Programme of the Moscow-based International Science and Technology Centre. It brings together VNIITF scientists with those of the Institute of Mathematical Modelling and the Institute of Numerical Mathematics.

© Macmillan Publishers Ltd

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