Ноябрь 2005 г. |
Российская наука и мир (по материалам зарубежной электронной прессы) |
innovations report - Bad Homburg, Germany / 04.11.2005
Plane-Trees Used To Grow In Siberia 85 Million Years Ago
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85 миллионов лет назад в Западной Сибири росли платаны. Такое открытие сделала экспедиция Ботанического института имени Комарова РАН в Санкт-Петербурге под руководством доктора биологических наук Л.Б. Головневой, обнаружив в Кемеровской области местонахождение ископаемых остатков растений середины мелового периода. Других местонахождений растений этого возраста в Западной Сибири пока неизвестно.
The Cretaceous that lasted approximately from 135 through 65 million years ago was the period of drastic changes in biosphere. It was at that time that mass extinction of dinosaurs and other reptiles took place; birds and mammals came to take their place. In the early Cretaceous, the first flowering plants appeared, they quickly occupied the dominant position overland and settled in diverse ecotopes. These large-scale processes, thanks to which the Earth gradually acquired the contemporary appearance, draw rapt attention of researchers.
In Western Siberia, only few locations of the Cretaceous plant remains exist, therefore, each new find of them brings the most valuable information on flora evolution in this vast territory. One of such finds was made quite recently, in July 2005, by palaeobotanist Lina Golovneva, specialist of the Komarov Botanical Institute, Russian Academy of Sciences (St. Petersburg), and her colleagues in the expedition organized with support of the Russian Foundation for Basic Research. The researchers worked near Antibes village in the Kemerovo Region, where on sandy slopes of desolated open pits they found clay interlayers containing multiple imprints of ancient plants' leaves. According to the preliminary estimate, their age makes approximately 85 million years; they used to grow back in the Coniacian stage of the Cretaceous. Other locations of plants of this age are not yet known in Western Siberia.
The majority of plant remains found near Antibes are imprints of tree leaves known under the scientific name of trochodendroides (which relate to contemporary redbud - a beautiful tree from Japan and China that is also sometimes cultivated in Russian parks) and paraprotophyllum (a close relative to a plane-tree normally growing in the Caucasus, the Crimea and along boulevards of Paris). The bilobate leaves of liriophyllum are found more rarely in this area; their shape reminds that of the North American tulip-tree's (liriodendron's ) leaves. There also were discovered imprints of a peculiar fern, resembling Venus' hair, its reproductive organs however having a totally unique structure.
Strictly speaking, phytolites near Antibes village were for the first time found back at the end of the 20s of the last century by Professor V.A. Khaklov (Tomsk University); at the end of the 30s, they were investigated by student V.K. Cherepnin. Unfortunately, these scientists managed to collect only one and a half dozens of specimen, which is evidently insufficient for a more or less complete characteristic of the ancient flora. The open pit where they found remains of ancient plants does not exist any longer.
Although Lina Golovneva had set off for Antibes to follow in the tracks of V.A. Khaklov and V.K. Cherepnin, the location she discovered turned out really new. And much more "productive" than those found by her predecessors: about one and a half hundred of plant specimen were collected here belonging to at least 16 species. Possibly some of these species are new to science, their detailed investigation is still ahead.
So, 85 million years ago, forests of trees related to modern plane-trees used to grow in the south of Western Siberia instead of today's taiga and forest-steppe. Apparently, the climate was warm and mild at that time; such trees would not endure the present Siberian winter. How long these deciduous forests existed and what vegetable communities came to take their place - is yet unknown; only new finds of extinct plants' remains will be able to provide answers to these questions.
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MOSNEWS / 07.11.2005
Russia, China to Jointly Explore Moon and Mars |
В Пекине состоялась десятая встреча премьер-министров России и Китая. Помимо всего прочего стороны заключили соглашение о долговременном сотрудничестве в сфере космических исследований.
Russia and China have agreed to launch in 2007 a 10-year space cooperation plan with a focus on joint development of major projects, such as a joint lunar exploration and landing on Mars, the Zhongguo Tongxun She news agency reported.
The two sides agreed to "explore the possibility of cooperation in the moon and deep space exploration" as well as joint development of large space projects, according to the joint communique issued at the 10th regular meeting between Chinese Prime Minister Wen Jiabao and his Russian counterpart Mikhail Fradkov last week.
China is still at the initial stage in the lunar and outer space probe and Sino-Russian cooperation in the sector will speed up China's pace in space exploration and avoid many detours, Pan Houren, a researcher with the Space Science and Application Research Centre of the Chinese Academy of Sciences, was quoted by the Press Trust of India as saying.
"Chang'e-I", China's first lunar exploration satellite is scheduled to be launched in 2007 for the country's first fly-by mission. The Chinese moon-landing plan might be achieved by 2012, but this plan would require Russian aid. Russia also plans to send a probe to the moon at that time. The launch of a Mars-orbiting satellite may be made between 2008 and 2009.
On the whole, by 2007 there will be around 10 more special space cooperation projects between China and Russia, Russian officials promised.
Copyright © 2004 MOSNEWS.COM
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AlphaGalileo / 03 November 2005
Health Of Crops Depends On "Protein Wars"
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Российско-белорусская группа биохимиков разрабатывает способ защиты зерновых культур от патогенных грибков. Исследования проводятся при поддержке РФФИ и Белорусского республиканского фонда фундаментальных исследований.
Interesting facts have been discovered in phytoimmunity sphere by the Russian-Belorus group of biochemists in the framework of the Russian Foundation for Basic Research and Belorus Foundation for Basic Research projects. To protect themselves from pathogenic fungi, which penetrate plant tissues with the help of proteinase proteins, vegetables produce inhibitors to these proteinases. A peculiar "arms race" is taking place between them.
Animals' immune system cells are aimed at resistance within the organism but phytoimmunity is mainly based on preventing the pathogen from "drilling a hole" in the integuments and defending itself from a vegetable antibiotic. Fungi penetrate plant tissues with the help of proteinase enzymes which decompose proteins of cellular walls and antimicrobial proteins.
Researchers have assumed that a plant organism should produce appropriate inhibitors to protect itself from these enzymes.
Specialists of the Lomonosov Moscow State University, Bach Institute of Bioorganic Chemistry, Russian Academy of Sciences and the Belorus Institute of Experimental Botany decided to check if plants' resistance to parasitic fungi is connected with inhibitor proteins' activity.
Biochemists investigated to what extent vegetal matters are capable of "turning off" various proteinases as bovine trypsin and similar enzymes complexes used by microbes and pathogenic fungi.
It has turned out that phytoimmunity is connected with synthesis of proteins inhibiting trypsin, chymotrypsin and subtilysine action, as well as with synthesis of complicated enzymatic mixtures excreted by phytopathogens.
For experiments biologists selected several kinds of cereals, legumes and buckwheat. Proteinases' inhibitors were extracted from their seeds and proteinases were extracted from laboratory cultures of these fungi (having removed mycelium from culture broth). After the mixtures of substances were obtained they were allowed to react. Inhibitory activity of seeds' extracts can be judged by the change of reaction mixture transparency. This is measured by chemists with a special device.
It has turned out that different cultures and sorts specialize in inhibiting different enzymes: Wheat mainly inhibits subtilysine. Triticale (wheat and rye hybrid) inhibits trypsin. Sorts that are low susceptible to fungus diseases turn out to have more protease inhibitors at their disposal than highly susceptible ones.
Biologists have discovered that abundance of chymotrypsin and subtilysine inhibitors block way to covered smut and root rot, and substances inhibiting trypsin activity impede downy mildew.
Fermentative relation between a plant and parasites may be presented as arms race: a parasite produces a destructive enzyme, and the plant - produces its inhibitor. Health of green plantations and crops depends on the "arms race" outcome.
© AlphaGalileo Foundation 2003
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innovations report / 04.11.2005
Smart Spring - Moscow Scientist Invents Unusual Water Purification Filter
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Рано или поздно поры фильтрующих материалов забиваются, и их нужно менять. Это особенно неудобно при фильтрации токсичных или радиоактивных веществ. Фильтрующие элементы Крапухина (ФЭК), представленные на 13-й Международной выставке "Химия-2005", можно использовать, не опасаясь их остановки.
Pores never become clogged in this filter - because there are no pores at all. The filter is designed in a different way.
The device invented by V.B. Krapukhin, Ph. D. (Engineering) was shown for the first time at the recent "Chemistry-2005" exhibition in Moscow where constantly crowded near the exhibition booth. The most heard comment was "simple like everything ingenious".
The water purification filter looks as follows:
There is a tank containing troubled, evidently dirty water, and another tank - containing clean, filtered water. Between them, there is a transparent either plastic or glass cylinder, inside which there a sort of stick covered by dense dark grey thin coating. Naturally there are also communication pipes, pumps, manometers. Suddenly, after some manipulation by the author demonstrating his invention, purified water stops running into the tank, grey coating gets troubled, unattractive content of the cartridge runs out backwards - into the tank with dirty water. A a shining spring is revealed inside, the zest of invention, its kernel.
How does this work?
In the operating position spring coils are pressed together tightly. Water gets into the cartridge under pressure and, having gone through the filter-spring, runs out already purified from dirt. Particulate pollutants larger than a micron remain in the cartridge. They are unable to squeeze through the spring coils. This is it, as simple as that.
"Normally, after several filtration-regeneration cycles were performed, pores of known filter mediums, such as cardboards, fabrics and others got irreversibly plugged up with solid phase particles." - explains V.B. That is why in the long run filter elements have to be extracted and replaced with new ones. Filter materials turned into waste, which, in case of toxic or radioactive contamination, had to be reclaim or buried. New filters had to be bought, consuming time and money which is not superfluous.
Apparently, the new filter element is free from such disadvantages - due to the lack of source of disadvantages, i.e. removable filters. Simple flushing within several minutes puts the spring back to operating condition. The filter design is quite multi-purpose - this method is suitable for purification of various liquid and gas currents. The number of filtration-regeneration cycles may be practically endless.
However, the device is not universal. For example, it does not provide for chemical purification of water. It performs mechanical purification from impurity substances, their size exceeding a micron. So, the device will clean water from silt, for example, but certainly not from salts of hardness. If soluble compounds should be filtered off, this has to be done additionally. However, this is how it is commonly done. But there will be no need to change filters endlessly, or to live in constant fear that the current of dirt would clog the pores up, due to that the process would go wrong - unfortunately, this happens quite often with ususal filters. This is absolutely impossible in case of Krapukhin's filters, which can be cleaned and returned back to operating condition in no time. They are indeed cheap but good.
The filter element of the device has been developed by V.B. Krapukhin and his colleagues at the Institute of Physical Chemistry(Russian Academy of Sciences). The scientist work at the laboratory of physicochemical methods for radioactive elements localization.
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Medical News Today / 12.11.2005
Tuberculosis: Diagnosis Will Be More Precise
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20-21 октября в Москве прошла II Международная конференция "Молекулярная медицина и биобезопасность", в рамках которой обсуждались вопросы по генной и клеточной терапии, молекулярной диагностике, биобезопасности и биозащите. Один из затронутых вопросов - диагностика туберкулеза с учетом постоянных мутаций патогенных бактерий.
A diagnostic approach will allow to quickly and precisely identify the enemy - tuberculosis culture pathogene, the approach being based on the so-called subtraction hybridization. How it can help to identify "personality" of a dangerous bacterium was discussed by researchers from Moscow with their colleagues at the II International Conference "Molecular Medicine and Biosafety" in late October this year.
For smatterers the notion of tuberculosis - is necessary and sufficient for definition of the disease and its pathogene, tubercle bacillus or, in other words, Koch's bacillus, and has long ago lost romantic veil of Chekhov's and Dostoyevsky's hectic heroines. However, specialists know well that considerable genetic variability is typical of the Mycobacterium tuberculosis bacteria population. Simply speaking, these pathogenes may be very different. On the one hand, according to the force of influence on human beings: some pathogens are more, figuratively speaking, "wicked" (virulent), others - are less wicked. It is necessary to know where the difference lies - what changes in the microorganism's genome cause changes in its properties, including changes in its virulence.
Furthermore, tuberculosis pathogens, like cockroaches, are able to adapt themselves to the circumstances. If they are exterminated by people, part of them dies, but the remaining ones produce posterity resistant to the applied poison. In case of tuberculosis, this is becomes apparent in occurrence of cultures resistant to this or that kind of drugs. Therefore, to treat for sure physicians use several drug substances at once - they fight, so to say, through extended front. On top of the fact that the patient gets high doses of 'redundant' drugs, which are far from innocuous for a patient, as a result of such mass attack there appear cultures with multiple drug resistance, and this is a real headache for those who is trying to cure the disease.
To recognize what particular culture caused a certain patient's disease, to study properties of this culture and, finally, to choose the most efficient and safe drug will be possible with the help of the method being developed under the guidance of Academician Evgeni Sverdlov by specialists of the Shemyakin and Ovchinnikov Institute of Bio-organic Chemistry (Russian Academy of Sciences) and their colleagues from the State Research Center for Applied Microbiology (Obolensk). Being concerned by tuberculosis attack on Russia and worldwide, the International Science and Technology Center, Ministry of Industry, Science and Technology, Russian Academy of Sciences (in the framework of the "Physicochemical Biology" program) and the Foundation of the President of the Russian Federation sponsored the researchers' effort.
"The subtraction hybridization method is rather difficult for explanation," says Nikolai Gvozdevsky, one of the participants to the project. "In a general way, the concept is that DNA molecules of the known and investigated culture are "clipped" into parts in a certain way at full length, these parts are marked on both sides and they are mixed in a certain ratio. Then each part is divided into two parallel nucleotide sequences (DNA, as we know from times of Watson and Crick, is a spiral consisting of two complementary, i.e. fitting to each other in a unique way, nucleotide chains), and then these two untwisted parts are allowed to join again. Thanks to some experimental techniques, the results allow to identify which DNA sections distinguish one culture from the other and to single out these sections. A vast electronic card file already available for DNA sequences of some widespread mycobacterial cultures, for its part, may help to determine which section of the genome was found as a result and which protein product this gene (DNA section) may code."
"Then the researchers use the found genomic sequences (unique for certain mycobacteria) for testing a large population sampling of pathogens for presence of these particular sequences. Unknown clinical isolate of M. tuberculosis may contain or not contain such a genetic marker in its genome composition. To answer the question "yes or no" allows another method called the PCR - polymerase chain reaction, perhaps one of the most widespread experimental approaches now in molecular clinical diagnostics. As a result of such analysis a set of final "yes" and "no" is obtained relating to all genes found in the course of subtraction hybridization, it allows like a binary code to group mycobacterial isolates and to recognize what particular culture got into the researcher's test-tube."
In the course of their investigation the researchers not only studied about two hundred clinical isolates educed from samples of patients' phlegm, but also discovered three genes in the genome of one of the cultures, which were not present in the genomes of other cultures. These genes are interesting by the fact that they are typical of the isolate which is the most virulent of all. The researchers assume that these gene specifically are responsible for unusually high malicious 'sociability' of this culture - its ability to interact with the host organism and correspondingly its special danger (virulence) to the host.
©2003-2005 Medical News Today
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LE MONDE / 11.11.05
Les chercheurs russes se plaignent de la faiblesse de leurs moyens
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Российские специалисты по исследованию и наблюдению за распространением птичьего гриппа считают, что не располагают достаточно эффективными методами для этого. Проблему также представляет недостаточное финансирование исследовательских проектов.
Les spécialistes russes de la surveillance et de la recherche sur l'épizootie de grippe aviaire provoquée par le virus H5N1 ont dénoncé, jeudi 10 novembre, le manque de moyens dont ils disposent alors que quatre régions de leur pays sont désormais touchées et que la Russie joue un rôle clef dans la progression de l'épizootie vers l'Europe et l'Afrique.
Adoptant une démarche inhabituelle, Valentin Pokrovski, président de l'Académie russe des sciences médicales, a déclaré, lors d'une conférence de presse, qu'il n'y avait aujourd'hui, en Russie, aucun financement spécifique pour les recherches sur l'épizootie. "Nous continuons à nous débrouiller avec les faibles moyens qui nous ont été accordés pour l'ensemble des recherches scientifiques", a-t-il expliqué. Pour Oleg Kisselev, directeur du Centre russe de recherches sur la grippe, "les perspectives de financement des projets russes de production industrielle de vaccins contre la grippe restent floues".
Basé à Saint-Petersbourg, ce centre s'était engagé à élaborer un prototype de vaccin contre la grippe d'ici mars 2006. "La production des premiers vaccins expérimentaux a déjà commencé, mais ils doivent encore être testés sur des humains, a précisé M. Kisselev. Toutefois, il faut un financement suffisant. Et les bourses versées aux instituts de recherches russes par des organisations internationales ne peuvent pas régler ce problème."
LIGNE DU TRANSSIBÉRIEN
L'initiative des chercheurs russes survient au lendemain de la conférence mondiale sur la grippe aviaire. Il y a un mois, ils avaient demandé à l'Office international des épizooties de trouver au plus vite une aide internationale. La Commission européenne vient de donner un accord de principe pour financer un projet d'amélioration des moyens virologiques de diagnostic et la formation des experts russes.
Selon les dernières données officielles, l'épizootie est localisée dans l'Oural (Kourgan et Tcheliabinsk), le territoire de l'Altaï, en Sibérie, et à Tambov, une ville située au sud-est de Moscou. Les experts russes pensent que le virus H5N1 est apparu dans leur pays en juillet, après avoir été introduit par des oiseaux migrateurs venant de Chine. D'autres experts, dont ceux de l'Agence française de sécurité sanitaire des aliments (Afssa), observent que les foyers de grippe aviaire déclarés en Russie sont tous alignés le long de la ligne du Transsibérien, ce qui ne plaide pas en faveur de l'hypothèse de contamination par les oiseaux migrateurs.
"Le commerce d'oiseaux vivants légal ou illégal est, avec les migrations, l'une des deux grandes causes possibles de la propagation de l'épizootie", expliquait, le 19 octobre, Philippe Vannier, directeur de la santé animale à l'Afssa, devant la mission parlementaire française d'information sur la grippe aviaire.
©Le Monde.fr
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