Российская наука и мир (дайджест) - Август 2007 г.
Навигация
Дайджест за другие годы
Август
2007 г.
Российская наука и мир
(по материалам зарубежной электронной прессы)

январь февраль март апрель май июнь июль август сентябрь октябрь ноябрь декабрь

    Daily Telegraph / 01/08/2007
    "Siberian forest fires due to climate change"
    • By Roger Highfield, Science Editor

    "Journal of Climate" опубликовал выводы международной группы ученых, заключившей, что катастрофические лесные пожары в Сибири происходят под влиянием климатических изменений. Среднегодовая температура в Сибири повышается быстрее, чем в среднем по миру. К 2090 году нынешняя лесная зона в Западной Сибири может настолько высохнуть, что деревья погибнут и тайга превратится в степь.

Devastating forest fires in Siberia that send a pall of smoke worldwide are happening more frequently because of climate change and in turn accelerating the pace of global warming, scientists claim.
In Central Siberia alone fires destroyed 15,000 square miles in 2003, triggering plumes which were linked with air pollution measured as far away as America. The forest fires send as much greenhouse gas into the atmosphere as the total EU reduction commitment under the Kyoto protocol.
In the Journal of Climate, an international team concludes that Siberian fires are influenced by climate change. The study was led by the Professor Heiko Balzter of the Department of Geography at the University of Leicester.
Prof Balzter said "Last century a typical forest in Siberia had about 100 years after a fire to recover before it burned again. But new observations by Russian scientist Dr Vyacheslav Kharuk have shown that fire now returns more frequently, about every 65 years. At the same time annual temperatures in Siberia have risen by almost two degrees Celsius, about twice as fast as the global average. And since 1990 the warming of Siberia has become even faster than before."
"Siberia is a hotspot in the global climate system. Because the Siberian ecosystems are largely temperature controlled the region is strongly affected by global warming," said Prof Balzter. "Large amounts of greenhouse gases are currently locked in the permafrost and in organic soils, and if released could accelerate the greenhouse effect."
For the study, the scientists observed 18 years of satellite images of the region, and estimated the timing of the onset and end of the growing season, when the snow has melted and the plants take up carbon from the air during plant growth.
From 1982 to 1999 almost all Siberian ecosystems showed an earlier onset of spring, ranging from around three days per decade to six days. "Central Siberia has a more continental climate. The changes in the timing of spring and also in fire occurrence are linked to temperature changes," said Prof Balzter.
Global climate patterns also contribute - notably a warming of waters in the Pacific off the coast of South America, called El Niño, and a pattern of atmospheric pressure in the Arctic called the Arctic Oscillation, linked to the north Atlantic. "Towards the East Siberian coast the Pacific plays a more important role, and the El Niño phenomenon together with low rainfall determines what happens to the forest".
Under one of the climate scenarios developed by the Hadley Centre of the Met Office, the current forest zone in western Siberia - the largest unbroken tract of trees on the planet - could be so dried out by 2090 that the trees would die off and be replaced with steppe. As a consequence, the Arctic would warm so much that trees could grow at the shores of the Arctic Ocean in Northern Siberia, currently an arctic desert.

© Copyright of Telegraph Media Group Limited 2007.
* * *
    World Science - New York, NY, USA / Aug. 14, 2007
    Alien life… from dust particles?
    Группа ученых из Института внеземной физики Макса Планка (Германия), Института общей физики РАН и Сиднейского университета (Австралия) изучала поведение сложных смесей неорганических материалов в так называемой пылевой плазме (отличается от обычной наличием "пылинок" - крошечных частиц диаметром от 10 до 100 нанометров). До сих пор считалось, что плазма из-за хаотического движения ионов и электронов неспособна к самоорганизации. Однако компьютерная модель молекулярной динамики показала, что при определенных условиях "пылинки" могут собираться в длинные цепочки, которые закручиваются в спирали и взаимодействуют друг с другом. Такие особенности обычно характерны для организации живой материи, в частности, для ДНК. Результаты исследования опубликованы в журнале New Journal of Physics.

It's not what life is supposed to be made of. It's definitely not where life is supposed to be found. Yet it looks pretty alive, researchers say: it sustains itself, reproduces itself, interacts with its neighbors and evolves.
It's a mere computer simulation of dust, of a type similar to that which floats among stars, according to the scientists.
The investigators described the strange simulated dust - which takes on the form of corkscrew-shaped particles - in a paper published today in the New Journal of Physics. The findings hint at the possibility that life beyond earth may not necessarily use carbon-based molecules as its building blocks, as it does on Earth, they said. But the research also points to a possible new explanation for life on our planet, they added.
Life on Earth consists of organic molecules, which are simply large compounds of carbon. The notion that inorganic, or non-carbon based, dust may take on life is nothing short of alien. The stuff doesn't even contain silicon, which a few scientists have suggested could replace carbon as a building block for life (even that idea is mostly relegated to science fiction today.)
In the new research, scientists at the Russian Academy of Science in Moscow, the Max-Planck Institute for Extraterrestrial Physics in Garching, Germany and the University of Sydney, Australia, studied mixtures of inorganic materials in a plasma. 
Plasma is a gas-like substance whose atoms are stripped of the electrons, or electrically charged particles, that normally inhabit them. This separation leads the atoms to also become charged, because under normal conditions, the electron's charge cancels out that of the atom. Plasma is considered a fourth state of matter beyond solid, liquid and gas.
Until now, physicists assumed that there could be little organisation in such a cloud of particles. However, The Russian Academy's V.N.Tsytovich and colleagues found, using a computer model of molecular dynamics, that plasma particles can undergo self-organization as charges become separated. This results in microscopic strands of solid particles that twist into corkscrew shapes, or helical structures. These helical strands are themselves charged and are attracted to each other.
Quite bizarrely, not only do these helical strands interact in a surprising way in which like can attract like, they also undergo changes normally associated with biological molecules, such as DNA and proteins, say the researchers. They can, for instance, divide, or bifurcate, to form two copies of the original structure. These new structures can also interact to induce changes in their neighbours and they can even evolve into yet more structures as less stable ones break down, leaving behind only the fittest structures in the plasma.
So, could helical clusters formed from interstellar dust be somehow alive? "These complex, self-organized plasma structures exhibit all the necessary properties to qualify them as candidates for inorganic living matter," said Tsytovich, "they are autonomous, they reproduce and they evolve" .
He adds that the plasma conditions needed to form these helical structures are common in outer space. However, plasmas can also form under more down to earth conditions such as the point of a lightning strike. The researchers hint that perhaps an inorganic form of life emerged on the primordial earth, which then acted as the template for the more familiar organic molecules we know today.

© 2004-2006 World Science.

* * *

    AlphaGalileo / 14 August 2007
    Natural Oil In Baikal
    В шельфовой зоне озера Байкал происходит постоянный естественный выброс нефти и газа, с которым экосистемы озера успешно справляются. Этот вопрос изучили ученые Лимнологического института СО РАН (Иркутск) совместно с Институтом океанологии (Москва) и Институтом геохимии (Иркутск). Анализ байкальской нефти показал, что она образовалась в осадках в период олигоцена - раннего миоцена, то есть около 23 млн. лет назад. По наиболее вероятной гипотезе, нефть возникла из органики, захороненной в водоеме. Несмотря на постоянное образование на поверхности воды нефтяных пятен, покрытая ими площадь не увеличивается благодаря нефтеокисляющим бактериям.

The possibility that natural oil could get into Lake Baikal caused the transfer of the projected "Eastern Siberia - the Pacific Ocean" oil-pipe line father away from the of the UNESCO world heritage object. Fortunately, environment protectors have managed to achieve the transfer. However, Baikal has turned out to cope already with its own oil blowouts - there are oil seepages in the self zone of the lake. The lake's unique ecosystems successfully cope with them. However, no oil seepages should occur in the lake on top of that! The issue was investigated by the researchers of the Institute of Limnology, Siberian Branch, Russian Academy of Sciences (Irkutsk) jointly with the Moscow Institute of Oceanology and the Irkutsk Institute of Geochemistry.
On the coast of Middle and Southern Baikal, natural oil outcrops in the coastal steeps in the form of bitumen or it comes to the water surface from the bottom of the lake in the form of floating spherules, which make spots of up to a meter and a half in diameter. It was in 2003 that attention was for the first time drawn to oil traces in Baikal, when a dark spot on the ice was noticed from the satellite. Later, the researchers discovered an underwater 500-meter-high fuel spray, consisting of gas, oil and bottom water.
The Baikal oil analysis has proved that it was generated in the sediments, as it is usually the case with fresh deep water bodies during the Oligocene - early Miocene. According to the most probable hypothesis, this oil originated from organic matter buried in the water body. The researchers took samples of sedimentary rock in the form of cores nearby the oil fuel spray and at different distances from the spray to investigate oil and gas content in the samples. The oil and gas mixture comes into water in the form of gas bubbles covered by the oil film. The gas consists of methane (99%) and its homologues: butane, propane, pentane, hexane and others.
Apparently, oil penetrates the Baikal water via tectonic discharges. However, regardless of constant formation of new oil spots on the water surface, the area covered by them - about one square kilometer - does not increase. This testifies that oil gets quickly transformed in the lake. Mainly, thanks to microbiological community, where oil-oxidizing bacteria prevail. So, for the time being, the Baikal ecosystem efficiently copes with the natural carbohydrates contamination.
Nevertheless, the researchers emphasize that natural oil relief into the lake is incommensurable in scale to disastrous man-caused oil blowouts. This cannot serve as justification for petroleum production or oil transportation close to the lake.

© AlphaGalileo Foundation 2003.

* * *

    Information World Review - London, UK / 23 Aug 2007
    Thomson reveals geological citation patterns
    • By Daniel Griffin
    По данным компании Thomson Scientific, которая занимается сбором научной информации и владеет крупнейшей базой данных о научных публикациях - ISI Web of Knowledge, Российская академия наук занимает третье место в рейтинге наиболее влиятельных исследовательских организаций мира в области геологии. При составлении подобных рейтингов анализируются публикации в 11 000 научных журналов, издаваемых по всему миру. В базе данных компании находятся более 10 млн. статей, освещающих 22 научные дисциплины.

A recent study from Thomson Scientific, lists the most-cited published papers from 10 years of geological research. The information was compiled and analysed from 224 journals and over 150,000 listed papers since 1996.
The results were first published in the July/August edition of Science Watch. The subscription-based newsletter examines citation information held by Thomson Scientific in relation to the geo-science research world.
Major institutes in the US were ranked the highest; the U.S. Geological Survey and NASA received 23,172 and 20,303 citations respectively over the 10 year period. The Russian Academy of Sciences was cited 15,019 times placing the institute in fourth place while the Chinese Academy of Sciences was ranked in fifth place with 14,937 citations. The University of Cambridge was the only UK research organisation to make the top ten ranking with seventh place; it was cited 12,573 times.
Commenting on the results Christopher King, editor of Science Watch said, "When institutions are ranked according to total citations, larger institutions tend to have an advantage due to the sheer abundance of published papers they produce. Therefore it is not surprising that large governmental institutions such as the US Geological Survey and NASA top the list."
Although the US had the highest number of most-cited researchers with the UK in second place; Frank C. Hawthorne, University of Manitoba in Canada was cited more times than fellow scholars for his crystallography and mineralogy work.
The most cited journal was the Geophysical Research Letters publication, with over 116,000 citations. The nearest rival was Geology, which was cited around 42,000 times.

© Incisive Media Investments Ltd. 2007.

* * *

    International Herald Tribune - France / August 22, 2007
    Two Russian scientists targeted for allegedly releasing state secrets
    Очередное дело о "разглашении государственной тайны". На этот раз под уголовное преследование попали доктора физико-математических наук, братья Олег и Игорь Минины, написавшие книгу к юбилею Института прикладной физики СО РАН. При этом в работе ученых использовались только открытые источники. В издании рассказывается об истории института, а также о его последних разработках.

MOSCOW: Russian security services are investigating two scientists for allegedly revealing state secrets, a probe that rights activists on Wednesday said highlights the chill that has fallen over Russian scientific research under President Vladimir Putin.
Oleg and Igor Minin are the latest in a growing number of academics who have been targeted by the Federal Security Service for alleged espionage, revealing state secrets or misuse of classified information.
The service, also known as the FSB, said in a statement that the two scientists published a booklet last year that outside experts determined contained classified information "related to the development of armaments." The evidence is being considered for possible prosecution, the FSB said.
The brothers, who are physicists at the State Technical University in Novosibirsk, could not be reached for comment Wednesday. Defense lawyer Lev Bauman said no crime was committed, and another lawyer, Mikhail Kizhin, told Russian news agencies that he would seek new independent experts to consider whether the material was classified.
Ernst Chyorny, a rights activist who acts as an advocate for scientists facing prosecution, said Russian security services continue to operate under a Soviet mindset encouraged Putin, himself a former KGB officer.
"In my view, this is even worse than the Soviet regime," he said. "Look, they take away people and put them away even though the evidence proves there is nothing (illegal) whatsoever and still innocent people remain behind bars."
Several recent cases have hinged on questions of whether information was obtained through open sources or was classified.
Arms control researcher Igor Sutyagin was convicted of treason in 2004 for allegedly selling information on nuclear submarines and missile-warning systems to a British company that Russian investigators claimed was a CIA cover. And physicist Valentin Danilov was found guilty of selling classified information on space technology to China.
Oleg Korobeynichev, a Novosibirsk chemist who works at an institute of the Russian Academy of Sciences, also faced charges of divulging state secrets last year. His laboratory worked with the U.S. Lawrence Livermore National Laboratory among other scientific institutes.

Copyright © 2007 the International Herald Tribune All rights reserved.

* * *

    Le Monde - Paris, France / 30.08.07
    Un énorme séisme dans les 10 à 15 ans au lac Baïkal (expert russe)
    По мнению российского специалиста Геннадия Черкасова, в ближайшие 10-15 лет в районе озера Байкал возможны землетрясения силой до 12 баллов по шкале Рихтера. Последний раз землетрясение такой силы было в 1920-х годах.

Un énorme séisme de magnitude 10 à 12 sur l'échelle ouverte de Richter, comme celui survenu dans les années 20, est probable dans la zone du lac Baïkal, en Sibérie, dans les 10 à 15 ans, a déclaré mercredi un expert russe à l'AFP.
"Le lac est au centre d'une zone sismique très active qui s'élargit régulièrement", a rappelé ce scientifique, Guennadi Tcherkassov, spécialiste du Baïkal auprès du ministère des Ressources naturelles de Russie à Moscou.
Statistiquement, un "tremblement de terre très puissant" devrait avoir lieu "dans les 10 à 15 ans", a-t-il ajouté.
Début août, une secousse de magnitude 4,8 sur l'échelle de Richter est survenue à 30 km au sud-est du village Elantsy, situé sur la rive occidentale du lac.
Dans les années 20, un très puissant séisme avait englouti deux villages, a noté le scientifique. La ville d'Irkoutsk, métropole régionale, est située à moins de 200 km de l'épicentre de plusieurs séismes précédents.
Sous la pression des défenseurs de l'environnement et experts scientifiques, le président russe Vladimir Poutine a accepté en 2006 un changement du tracé de l'oléoduc que la Russie doit construire entre la Sibérie et l'océan Pacifique, qui passera à 400 km du lac Baïkal et non à quelques mètres comme prévu initialement.
D'une superficie de 3,15 millions d'hectares, le Baïkal, inscrit depuis 1996 sur la liste du Patrimoine mondial de l'Unesco, est le plus ancien (25 millions d'années) et le plus profond (1.700 m) lac d'eau douce du monde. Il abrite 20% des eaux douces non gelées de la planète.

© Le Monde.fr.

* * *


январь февраль март апрель май июнь июль август сентябрь октябрь ноябрь декабрь

предыдущий месяц
1998-2007
следующий месяц
[О библиотеке | Академгородок | Новости | Выставки | Ресурсы | Библиография | Партнеры | ИнфоЛоция | Поиск]
  © 1997–2024 Отделение ГПНТБ СО РАН  

Документ изменен: Wed Feb 27 14:56:44 2019. Размер: 27,958 bytes.
Посещение N 6015 с 07.09.2007