Март 2012 г. |
Российская наука и мир (по материалам зарубежной электронной прессы) |
Science Careers Magazine / March 02, 2012
Taken for Granted: Foreign Invasion
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В Science Career Magazine (электронное приложение к журналу Science) опубликован отзыв на работу американских экономистов Джорджа Борхаса и Кирка Дорана "Распад Советского Союза и производительность труда американских математиков", в которой рассматривается влияние на американскую науку советских ученых, эмигрировавших в США после распада СССР.
Публикация "The Collapse of the Soviet Union and the Productivity of American Mathematicians" доступна на сайте Национального бюро экономических исследований США (NBER) (http://www.nber.org/papers/w17800).
The idea that the United States needs more scientists in order to produce more science has become a mantra among government, industry, and academic leaders seeking to energize the lagging economy. The major role of innovation in the nation's prosperity gives the notion intuitive appeal.
"Knowledge produced by one researcher is both an output and an input into another researcher's [work]," write economists George Borjas of Harvard University and Kirk Doran of the University of Notre Dame in a recently published study. "Not surprisingly, there is a consensus among policy makers that increases in the supply of a highly skilled workforce will increase the productivity of the preexisting workforce, and lead to a substantial increase in national wealth."
But is this idea actually true? "The Collapse of the Soviet Union and the Productivity of American Mathematicians," the intriguing and important article from which I borrowed that quotation, raises serious doubts. Borjas and Doran have cleverly turned the major geo-political event of the 1990s into a natural experiment to find out what can happen when immigration sharply boosts the number of researchers in a scientific field. By tracking the large influx of Russian mathematicians into the United States following the Communist regime's demise, they found a number of significant effects.
An overall increase in research production, however, was not among them. Instead, the output of American mathematicians whose research interests coincided with the Russians' actually "shrank," the paper states. The recent arrivals' work did "fill the gap" in numbers of publications, but "there is no evidence that they greatly increased the size of the "mathematics pie". "The point of the paper," Borjas tells Science Careers in an interview, is that "it's certainly true that high-skill immigrants will bring in new ideas and some of these ideas will rub off on us, and be innovative and productive. … But it's also true that supply and demand work."
The Russians are coming
The fall of the Iron Curtain in late 1991 ended nearly 70 years of isolation of Soviet mathematicians from the world mathematical community. Suddenly free to travel and emigrate, approximately 1000 Soviet mathematicians, mostly highly productive researchers, relocated to other countries. Three-hundred-thirty-six scientists came to the United States.
During the decades of scant contact with foreign colleagues, Russian mathematicians, for political reasons that Borjas and Doran explain, concentrated on certain fields that tended to get much less attention in the West. American mathematicians, meanwhile, had moved ahead in areas that Russians largely ignored. When the émigrés arrived in America, therefore, they had a great impact on certain mathematical fields but much less on others.
These differential impacts allow Borjas and Doran to compare what happened in fields heavily and lightly affected by the influx and to analyze what a large infusion of new talent and ideas does to a field of research. Combining information from several large databases, they track the productivity and affiliations of the Russian and American mathematicians. Their inquiry concentrates on two major effects; the "knowledge shock" from all of the new approaches and insights suddenly available to American mathematics, and the "labor market shock" from all the new people suddenly on the American mathematics job market.
What they found does not support what Borjas calls the conventional "rubbing-off" theory, which holds that if "we get all these highly skilled immigrants, … somehow there's a rubbing-off effect that makes you and me more innovative."
Since the fields with heavy Russian influence had "incredibly bright new mathematicians coming in, with all these new theorems, all these new techniques flooding the market, you would expect that people working in those areas are going to learn quite a lot from them," Borjas says. "At the same time, the number of academic jobs where mathematical research is actually done is really not increasing all that much. So something has to give."
That something, the study found, was the career prospects and productivity of many of the mathematicians already here. "When you increase the number of very smart people in a field by a substantial amount," Borjas says, "… not everybody benefits. The typical pre-existing American mathematician actually lost out."
That's because "a generation of American mathematicians at the very peak of their mathematical efficiency by luck just happened to graduate at the same time these Russians [were] coming in," Borjas explains. The people of that young generation lost the most. Faculty members protected by tenure kept their jobs, but mathematicians who had not yet attained it found themselves facing sharply heightened competition, which produced an "unprecedented 12 percent unemployment rate for new American mathematics PhDs" and "a dramatic decrease in the probability of obtaining a position in research universities," the article says. The overall unemployment rate for college graduates, meanwhile, was dropping rapidly, from 3.2% to 2.2% between 1992 and 1996. Many of the young mathematicians in heavily affected fields ended up moving to lower-ranking institutions or leaving academic mathematics altogether.
The situation "drove a lot of American mathematicians into Wall Street," Borjas says. There, in their new role as "quants" (quantitative analysts), they turned their talents to inventing intricate financial instruments. Ironically, one of Borjas's colleagues has joked, the migration from the formerly communist country probably helped to fuel the 2008 economic crisis that nearly brought down American capitalism.
The market in ideas
The mundane workings of labor market supply and demand may be the stuff of Economics 101, but didn't all the ideas the Russians brought boost research? The "rubbing-off" theory argues that they should have done just that. But even there, Borjas says, "The constraints of the market were way too strong."
"The actual post-1992 output of mathematicians whose work most overlapped with that of the Soviets and hence could have benefited more from the influx of Soviet ideas is far below what would have been expected" compared with former productivity and Americans' productivity in other fields, the paper states. Many in the heavily affected fields "ceased publishing relatively early in their career. [Also] they became much less likely to publish a 'home run' paper after the arrival of the Soviet émigrés." As in the job market, these Americans often found their papers crowded out of the limited number of available journal publication slots, especially in the premier journals, and their ideas crowded out of the center of attention in their field.
"Even if the ideas of a highly qualified single worker spill over to other workers with whom they interact, the overall effect of the interaction can still be deleterious to the productivity of other workers," the article concludes. "In particular, in a world with constraints on the funding and dissemination of ideas (e.g., a limit on the number of faculty slots, or, more abstractly, a limit on the attention span of the potential audience), large and sudden increases in the population of producers of knowledge can result in diminishing marginal productivity for a pre-existing worker," it continues.
"Even if the supply of jobs wasn't fixed and the tenure system wasn't in place, the fact of the matter is that the leaders of the field couldn't really have consumed all this new stuff. … There are only so many hours in a day," Borjas says. What's more, "the loss of a generation of American mathematicians led to the loss of a lot of theorems that perhaps could have been important. We'll never know that."
But we do know that "constraints … limit the amount of rubbing-off effect that you can actually enjoy," he goes on. "You could fill up the world with new ideas, but they all can't really be consumed" in the available time and attention. In terms of supply and demand, Borjas says, "Producing theorems is no different than producing widgets."
Implications
Borjas and Doran staunchly decline to discuss their work's implications for immigration policy. And Borjas emphasizes that "you can't take this paper and say it will apply in every single context in the world" because the data reveal different effects from the Russian mathematical influx depending on local factors.
At least one conclusion, however, seems clear. It is not the raw numbers of researchers but the institutional arrangements in which they work that shape the course of productivity and innovation. The American academic system, whose main features have changed little since the 1990s, could not take optimal advantage of either the new ideas or the new people. Instead, the system irreversibly wasted both talent and possibility and altered the incentives that influenced talented young Americans' career decisions.
This does not, however, in itself argue against welcoming highly skilled immigrants and their ideas. Instead, it argues for crafting science labor force policies based on the real effects that they are likely to produce, not on the ones that people hope for or imagine.
© 2012 American Association for the Advancement of Science. All Rights Reserved.
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UB News Center / March 2, 2012
Unexpected Crustacean Diversity Discovered in Northern Freshwater Ecosystems A new species adds to evidence that subarctic regions with vanishing waters contain unique aquatic animals
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Американские и российские ученые (Университет Буффало и Институт проблем экологии и эволюции им. А.Н.Северцова РАН) обнаружили, что в пресноводных экосистемах северных широт обитает куда большее количество видов ракообразных, чем считалось ранее.
Статья "A revision of the subgenus Eurycercus (Eurycercus) Baird, 1843 emend. nov. (Cladocera: Eurycercidae) in the Holarctic with the description of a new species from Alaska" опубликована в журнале Zootaxa (N 3206; 2012).
BUFFALO, N.Y. - Freshwater ecosystems in northern regions are home to significantly more species of water fleas than traditionally thought, adding to evidence that regions with vanishing waters contain unique animal life.
The new information on water fleas - which are actually tiny crustaceans - comes from a multi-year, international study that was published Feb. 24 in the journal Zootaxa.
The researchers scoured the globe seeking the creatures and found them inhabiting northern lakes and ponds in locations from Alaska to Russia to Scandinavia.
After analyzing the anatomy and genetic makeup of many different specimens, the team conclusively determined that at least 10 species of the crustaceans existed - five times as many as thought for much of the last century.
More than half the diversity was found in northern latitudes, where rapid freshwater habitat loss is occurring due to melting permafrost, increased evaporation and other changes tied to climate change.
"It is well known that parts of Alaska and Siberia have suffered a huge reduction in freshwater surface area, with many lakes and ponds disappearing permanently in the past few decades," said Derek J. Taylor, a University at Buffalo biologist and member of the research team. "What we're now finding is that these regions with vanishing waters, while not the most diverse in the world, do contain some unique aquatic animals."
"Some of these subarctic ponds that water fleas inhabit are held up by permafrost, so when this lining of ice melts or cracks, it's like pulling the plug out of a sink," Taylor said. "When you see the crop circle-like skeletons of drained ponds on the tundra you can't help but wonder what animal life has been lost here."
Taylor's colleagues on the study included Eugeniya I. Bekker and Alexey A. Kotov of the A. N. Severtsov Institute of Ecology and Evolution in Moscow.
The research focused on water fleas of the genus Eurycercus, which can reach lengths of about 6 millimeters. The findings add to a body of evidence suggesting that the species diversity of water fleas is greater in northern regions than in the tropics.
This is a counterintuitive concept, as scientists have long supposed that the advance and readvance of ice sheets reduced much of the species diversity in colder climates, Taylor said. However, there is growing evidence that some northern areas remained ice-free and acted as hideouts during the harsh glacial advances.
The researchers not only convincingly documented new species diversity, but identified one likely new species and provided a detailed, formal description of another: Eurycercus beringi.
Like other water fleas, E. beringi is an important source of nutrients for fish and aquatic birds.
The new species - from Alaska's remote Seward Peninsula - has unusual anatomical features that force a rewrite of the taxonomy of Eurycercus above the species level. Moreover, the new anatomical details should aid future studies that use preserved body parts of Eurycercus found in lake sediments to reconstruct past ecological conditions.
The discovery of new crustacean species in unexpected places underscores the scope of the ongoing biodiversity crisis for freshwater ecosystems.
The research was supported by the Biodiversity Program of the Presidium of Russian Academy of Sciences, the Russian Science Support Foundation, the Russian Foundation for Basic Research, the Smithsonian Institution Office of Fellowships and the National Science Foundation.
© 2012 University at Buffalo. All rights reserved.
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Voice of America / March 09, 2012
For Japanese Farmers, Lessons From Chernobyl
- Steve Herman, Koriyama, Japan
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В г. Корияма (префектура Фукусима, Япония) прошел симпозиум с участием российских, белорусских и украинских ученых по вопросам дезактивации загрязненных радиоактивными веществами территорий. Целью симпозиума было использование опыта ликвидации последствий аварии на Чернобыльской АЭС - после катастрофы на японской АЭС "Фукусима-1" в марте прошлого года сельхозугодия в префектуре оказались заражены.
Scientists from the former Soviet Union have arrived in Japan's Fukushima prefecture to advise locals on farmland decontamination.
One of Japan's most valued agricultural regions, the area was irradiated when three nuclear power plant reactors melted down in the wake of last year's earthquake and tsunami on the country's northeastern coast.
According to Japanese officials, 81,000 hectares of farmland are contaminated at a level above 5,000 becquerels per kilogram, the limit at which rice, by government decrees, cannot be planted.
Yoshi-ichi Takeda, a Fukushima dairy farmer, says the fallout has destroyed his livelihood along with that of nearby fruit and vegetable farmers.
"Emergency relief funds are barely enough to subsist," he says, explaining that the government won't allow his ten cows to graze and that officials have yet to indicate when his land will be decontaminated.
Just down the road in Nihonmatsu, Aiko Saito is trying to cultivate rice, peas, potatoes and radishes, but what she cannot find any buyers for her rice and vegetables. What Saito and neighboring farmers get for their crops has plummeted drastically. Her peas sold last year for half the usual price, and now even her own children refuse to eat what she grows.
Guidance From Abroad
At an unprecedented symposium on the outskirts of Koriyama, scientists from overseas meet with their Japanese counterparts and local officials. Invited by the government, they've come to share their experience with farmland decontamination.
Victor Averin, director of the Research Institute of Radiology in Belarus, says he wants to share knowledge acquired after the 1986 Chernobyl nuclear accident in Soviet-era Ukraine.
Telling the Japanese they must utilize experiences from Russia, Ukraine and Belarus to reclaim contaminated farms of Fukushima, he offers a practical tip: ferrocene, an organo-metallic compound effective in reducing radiation contamination in milk and poultry.
According to Rudolf Alexakhin, an expert with the Russian Academy of Sciences, it took nearly 20 years to reduce land contamination to safer levels after Chernobyl.
Given the large size of the contaminated land in eastern Europe, he says, it was impossible to effectively use absorbents or remove topsoil. But for Fukushima, which has a smaller area vital to Japanese agriculture, he says such methods will be effective.
One sobering science lesson for Japanese farmers: the soil. While European peat absorbed Chernobyl radiation, limiting transmission to crops, Japan's soil is sandy, which means a reduced absorption rate.
Victor Korsun, a top official at the Science and Technology Center of Ukraine, says the Japanese accident demonstrates that lessons of Chernobyl were insufficient. Aging nuclear plants, he says, need stricter scrutiny and better safeguards.
"Human beings the world over continued and continue to be at great risk," says Korsun. "We must recognize that the work of this conference is vital for the future of mankind."
A National Campaign
Japan's environment ministry is to begin a full-scale decontamination program next month. But the initiative generates a new dilemma: Where to place the removed radioactive soil?
Along with an accumulation of radioactive ash from incinerators and a huge amount of debris from the magnitude-nine quake and tsunami, residents in other regions are fighting efforts to have it relocated to their communities.
The situation has prompted the environmental ministry to launch a national campaign slogan, "Everyone's effort is needed for debris disposal."
So far, there is little evidence the message is finding a sympathetic audience.
© VOANews.com.
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Ecologie.tv / 2 mars 2012 Les russes réussissent la manœuvre de correction d'orbite pour l'ISS
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Подмосковный Центр управления полетами успешно провел коррекцию орбиты Международной космической станции для создания оптимальных условий стыковки с российским грузовым кораблем "Прогресс", запуск которого намечен на апрель.
La porte-parole du centre russe de contrôle des vols a annoncé hier la réussite de l'opération de changement d'orbite de la Station spatiale Internationale (ISS). Cet ajustement d'orbite est destiné à faciliter l'arrimage du cargo russe de ravitaillement Progress M-15M.
Le centre russe de contrôle des vols spatiaux (TsOUP) avait annoncé à la mi-février une opération d'ajustement de la distance orbitale de l'ISS en prélude à l'arrimage du cargo russe Progress M-15M. L'orbite de l'ISS devait être relevée de 3,3 Km par rapport à son niveau d'alors. Plus tard cette prévision de relèvement a été abaissée à 2,1 Km. C'est finalement ce niveau de relèvement qui a été adopté. La date du 29 février 2012, fut celle qui fut retenue pour la manœuvre. Elle débuta hier aux alentours de 14h18 min heure de Moscou, c'est-à-dire à 10h18 UTC. Les moteurs du module russe de service, le module Zvezda sont entrés en action durant 76,4 secondes et ont impulsé à la station spatiale Internationale une vitesse supplémentaire de 1,2 m/s. cette action a conduit l'ISS à prendre de l'altitude et son orbite s'est accrue de 2,1 km par rapport à son niveau précédent. L'altitude moyenne de l'ISS est désormais de 391,3 Km par rapport au niveau des mers.
Mission réussie donc pour les équipes du TsOUP, car ce sont elles qui ont entièrement coordonné depuis la terre cet ajustement de l'orbite de la Station Spatiale Internationale. La station est fin prête pour accueillir le cargo russe Progress M-15M, qui décollera le 20 Avril 2012 de la base de lancement Baïkonour au Kazakhstan. La Station Spatiale Internationale, plus connue sous son acronyme anglais ISS, est un projet développé conjointement par les européens, les américains, les russes et les canadiens. Il s'agit d'une station placée en orbite terrestre dont la construction a débuté en 1998 et devra s'achever en cette année 2012. Cette station, qui au final devra peser plus de 400 tonnes, est le plus gros objet jamais placé en orbite terrestre. Depuis 2000, des équipes internationales de scientifiques s'y relaient en permanence en vue de conduire diverses sortes de recherches. Cette station, qui a été assemblée progressivement dans l'espace, est continuellement alimentée en énergie électrique par un ensemble de panneaux solaires d'une superficie de 2500 mètres carrés. Cet ensemble lui fournit continuellement 110 KW d'électricité. Depuis la mise à la retraite de la navette spatiale américaine, les fusées russes sont les seules capables de ravitailler la navette spatiale et d'y conduire et d'en ramener les cosmonautes. L'ISS est actuellement occupée par un équipage de 6 membres dont 3 russes, deux américains et un néerlandais.
Tout droits réservés © Ecologie.tv.
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