249 research outputs found

    ΠŸΠ Π•Π”Π‘Π’ΠΠ’Π›Π•ΠΠΠžΠ‘Π’Π¬ ΠŸΠ£Π‘Π›Π˜ΠšΠΠ¦Π˜Π™ УЧЕНЫΠ₯ РАМН Π’ WEB OF SCIENCE: ΠžΠ¦Π•ΠΠšΠ Π’Π•ΠšΠ£Π©Π˜Π₯ ΠŸΠžΠšΠΠ—ΠΠ’Π•Π›Π•Π™ И ΠŸΠ•Π Π‘ΠŸΠ•ΠšΠ’Π˜Π’ ИΠ₯ Π£Π’Π•Π›Π˜Π§Π•ΠΠ˜Π―

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    The contribution scientific publications of Russian Academy of Medical Sciences (RAMS) in the national publication stream, indexed by Web of Science over the past thirty years, was estimated. The indicators of publication activity that are necessary for the institutions of RAMS to achieve in short-term period the conformity with bibliometric indicators, established by Presidential Decree of May 7, 2012 (to increase the share of Russian publications in Web of Science to 2.44% in 2015) were calculated. It is shown that the current structure of global science, where publications in medicine make up for approximately one third of scientific publications in the world, set for RAMS scientists particularly difficult task: to double in three years the number of publications in Web of Sci. In the article are proposed the priorities and the necessary steps to fulfill this task.Β ΠžΡ†Π΅Π½Π΅Π½ Π²ΠΊΠ»Π°Π΄ ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΉ ΡƒΡ‡Π΅Π½Ρ‹Ρ… РАМН Π² Π½Π°Ρ†ΠΈΠΎΠ½Π°Π»ΡŒΠ½Ρ‹ΠΉ ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΎΠ½Π½Ρ‹ΠΉ массив, ΠΎΡ‚Ρ€Π°ΠΆΠ΅Π½Π½Ρ‹ΠΉ Π² Web of Science Π·Π° послСдниС 30Β Π»Π΅Ρ‚. Рассчитаны ΠΏΠΎΠΊΠ°Π·Π°Ρ‚Π΅Π»ΠΈ ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎΠΉ активности, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ Π½Π΅ΠΎΠ±Ρ…ΠΎΠ΄ΠΈΠΌΡ‹ НИУ РАМН для достиТСния Π² краткосрочной пСрспСктивС соотвСтствия библиомСтричСскому ΠΈΠ½Π΄ΠΈΠΊΠ°Ρ‚ΠΎΡ€Ρƒ, установлСнному Π£ΠΊΠ°Π·ΠΎΠΌ ΠŸΡ€Π΅Π·ΠΈΠ΄Π΅Π½Ρ‚Π° Российской Π€Π΅Π΄Π΅Ρ€Π°Ρ†ΠΈΠΈ ΠΎΡ‚ 7 мая 2012Β Π³. (ΡƒΠ²Π΅Π»ΠΈΡ‡Π΅Π½ΠΈΠ΅ Π΄ΠΎΠ»ΠΈ российских ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΉ Π² Web of Science Π΄ΠΎ 2,44% ΠΊ 2015Β Π³.). Показано, Ρ‡Ρ‚ΠΎ слоТившаяся структура глобальной Π½Π°ΡƒΠΊΠΈ, Π² ΠΊΠΎΡ‚ΠΎΡ€ΠΎΠΉ Π½Π° мСдицинскиС ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΈ приходится ΠΎΠΊΠΎΠ»ΠΎ Ρ‚Ρ€Π΅Ρ‚ΠΈ ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎΠ³ΠΎ ΠΌΠΈΡ€ΠΎΠ²ΠΎΠ³ΠΎ ΠΏΠΎΡ‚ΠΎΠΊΠ°, ставит ΠΏΠ΅Ρ€Π΅Π΄ ΡƒΡ‡Π΅Π½Ρ‹ΠΌΠΈ РАМН особСнно ΡΠ»ΠΎΠΆΠ½ΡƒΡŽ Π·Π°Π΄Π°Ρ‡Ρƒ: ΡƒΠ΄Π²ΠΎΠΈΡ‚ΡŒ Π·Π° Ρ‚Ρ€ΠΈ Π³ΠΎΠ΄Π° количСство ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΉ, индСксируСмых Π² Web of Science. Π Π°ΡΡΠΌΠ°Ρ‚Ρ€ΠΈΠ²Π°ΡŽΡ‚ΡΡ ΠΏΠ΅Ρ€Π²ΠΎΠΎΡ‡Π΅Ρ€Π΅Π΄Π½Ρ‹Π΅ ΠΈ Π½Π΅ΠΎΠ±Ρ…ΠΎΠ΄ΠΈΠΌΡ‹Π΅ ΠΌΠ΅Ρ€Ρ‹ для выполнСния этой Π·Π°Π΄Π°Ρ‡ΠΈ.

    ΠŸΠ ΠžΠ‘Π›Π•ΠœΠ« Π­ΠšΠ‘ΠŸΠ•Π Π’Π˜Π—Π« Π‘Π˜ΠžΠœΠ•Π”Π˜Π¦Π˜ΠΠ‘ΠšΠ˜Π₯ ΠŸΠ ΠžΠ•ΠšΠ’ΠžΠ’ И ΠŸΠ Π˜Π‘Π’ΠžΠ•ΠΠ˜Π― ИМ БВАВУБА ΠŸΠ ΠžΠ Π«Π’ΠΠ«Π₯ И ΠœΠ˜Π ΠžΠ’ΠžΠ“Πž Π£Π ΠžΠ’ΠΠ―

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    There was a sharp increase in the number of scientific fields, research fronts, publications and patents in biomedicine in the last five years, whichcomplicates the work of the experts on the selection of projects for priority funding. The approaches to the identification of perspective directionsof research used in the world were examined. An attempt was made of formalization of the concepts of Β«breakthrough researchΒ» and Β«world levelresearchΒ» in relation to the Russian biomedical projects. The rationale for information support of expert decision-making about the prospects of development of individual areas of research in biomedicine is outlined.ΠžΡ‚ΠΌΠ΅Ρ‡Π΅Π½ΠΎ Ρ€Π΅Π·ΠΊΠΎΠ΅ ΡƒΠ²Π΅Π»ΠΈΡ‡Π΅Π½ΠΈΠ΅ числа Π½Π°ΠΏΡ€Π°Π²Π»Π΅Π½ΠΈΠΉ, Ρ„Ρ€ΠΎΠ½Ρ‚ΠΎΠ² исслСдований, ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΉ ΠΈ ΠΏΠ°Ρ‚Π΅Π½Ρ‚ΠΎΠ² ΠΏΠΎ Π±ΠΈΠΎΠΌΠ΅Π΄ΠΈΡ†ΠΈΠ½Π΅ Π·Π° послСдниС 5 Π»Π΅Ρ‚, Ρ‡Ρ‚ΠΎ услоТняСт Ρ€Π°Π±ΠΎΡ‚Ρƒ экспСртов ΠΏΠΎ ΠΎΡ‚Π±ΠΎΡ€Ρƒ ΠΏΡ€ΠΎΠ΅ΠΊΡ‚ΠΎΠ² для ΠΏΡ€ΠΈΠΎΡ€ΠΈΡ‚Π΅Ρ‚Π½ΠΎΠ³ΠΎ финансирования. РассмотрСны принятыС Π² ΠΌΠΈΡ€Π΅ ΠΏΠΎΠ΄Ρ…ΠΎΠ΄Ρ‹ ΠΊ Π²Ρ‹ΡΠ²Π»Π΅Π½ΠΈΡŽ пСрспСктивных Π½Π°ΠΏΡ€Π°Π²Π»Π΅Π½ΠΈΠΉ исслСдований. ΠŸΡ€Π΅Π΄ΠΏΡ€ΠΈΠ½ΡΡ‚Π° ΠΏΠΎΠΏΡ‹Ρ‚ΠΊΠ° Ρ„ΠΎΡ€ΠΌΠ°Π»ΠΈΠ·Π°Ρ†ΠΈΠΈ понятий Β«ΠΏΡ€ΠΎΡ€Ρ‹Π²Π½ΠΎΠ΅ исслСдованиС» ΠΈ «исслСдованиС ΠΌΠΈΡ€ΠΎΠ²ΠΎΠ³ΠΎ уровня» ΠΏΡ€ΠΈΠΌΠ΅Π½ΠΈΡ‚Π΅Π»ΡŒΠ½ΠΎ ΠΊ российским биомСдицинским ΠΏΡ€ΠΎΠ΅ΠΊΡ‚Π°ΠΌ. ΠŸΡ€ΠΈΠ²ΠΎΠ΄ΠΈΡ‚ΡΡ обоснованиС нСобходимости ΠΈΠ½Ρ„ΠΎΡ€ΠΌΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎΠΉ ΠΏΠΎΠ΄Π΄Π΅Ρ€ΠΆΠΊΠΈ принятия экспСртных Ρ€Π΅ΡˆΠ΅Π½ΠΈΠΉ ΠΎ пСрспСктивности развития ΠΎΡ‚Π΄Π΅Π»ΡŒΠ½Ρ‹Ρ… Π½Π°ΠΏΡ€Π°Π²Π»Π΅Π½ΠΈΠΉ исслСдований Π² области Π±ΠΈΠΎΠΌΠ΅Π΄ΠΈΡ†ΠΈΠ½Ρ‹

    ΠŸΠ£Π‘Π›Π˜ΠšΠΠ¦Π˜ΠžΠΠΠΠ― ΠΠšΠ’Π˜Π’ΠΠžΠ‘Π’Π¬ Π ΠžΠ‘Π‘Π˜Π™Π‘ΠšΠžΠ™ ΠœΠ•Π”Π˜Π¦Π˜ΠΠ‘ΠšΠžΠ™ НАУКИ Π’ Π€ΠžΠšΠ£Π‘Π• ΠΠšΠ’Π£ΠΠ›Π¬ΠΠžΠ™ ΠΠΠ£Π§ΠΠžΠ™ ΠŸΠžΠ›Π˜Π’Π˜ΠšΠ˜: ΠžΠ¦Π•ΠΠšΠ Π”ΠžΠ‘Π’Π˜Π–Π˜ΠœΠžΠ‘Π’Π˜ Π¦Π•Π›Π•Π’Π«Π₯ ΠŸΠžΠšΠΠ—ΠΠ’Π•Π›Π•Π™

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    A comprehensive review of National research policy papers issued over the past 6 years was carried out. A set of problems concerning the quality of predicted values of some bibliometric indicators reflecting the level of research performance and publication activity that were declared in governmental documents was discussed. Basic metrics of scientific performance that should be required to achieve the goals declared in the recent governmental policy papers including President’s Executive Order β„–Β 599 of May 7, 2012 (increasing the share of Russian researchers’ publications in the total number of publications in international scientific journals indexed in the Web of Science up to 2,44% in 2015). Taking into account the current structure of modern global science in which papers in biomedical subjects make up for approximately one third of the total world scientific output, it becomes obvious how difficult is the governmental task set up to the researchers β€” to double the number of journal publications indexed in Web of Science in the short-term period of the nearest three years. The priorities and reasonable goal-oriented efforts to meet the targets are proposed in the paper.Β ΠŸΡ€ΠΎΠ²Π΅Π΄Π΅Π½ Π°Π½Π°Π»ΠΈΠ· государствСнных ΠΏΡ€ΠΎΠ³Ρ€Π°ΠΌΠΌΠ½Ρ‹Ρ… Π΄ΠΎΠΊΡƒΠΌΠ΅Π½Ρ‚ΠΎΠ² ΠΏΠΎ Π½Π°ΡƒΡ‡Π½ΠΎΠΉ ΠΏΠΎΠ»ΠΈΡ‚ΠΈΠΊΠ΅, Π² ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Ρ… использовались ΠΈΠ½Π΄ΠΈΠΊΠ°Ρ‚ΠΎΡ€Ρ‹ ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎΠΉ активности ΠΈ ΠΏΡ€ΠΎΠ³Π½ΠΎΠ·Π½Ρ‹Π΅ ΠΎΡ†Π΅Π½ΠΊΠΈ роста Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚ΠΈΠ²Π½ΠΎΡΡ‚ΠΈ отСчСствСнных Π½Π°ΡƒΡ‡Π½Ρ‹Ρ… исслСдований. Рассчитаны основныС ΠΏΠΎΠΊΠ°Π·Π°Ρ‚Π΅Π»ΠΈ ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎΠΉ активности, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ Π΄ΠΎΠ»ΠΆΠ½Ρ‹ Π±Ρ‹Ρ‚ΡŒ достигнуты ΠΏΡ€ΠΎΡ„Π΅ΡΡΠΈΠΎΠ½Π°Π»ΡŒΠ½Ρ‹ΠΌ мСдицинским сообщСством, Ρ‡Ρ‚ΠΎΠ±Ρ‹ ΡΠΎΠΎΡ‚Π²Π΅Ρ‚ΡΡ‚Π²ΠΎΠ²Π°Ρ‚ΡŒ Ρ†Π΅Π»Π΅Π²Ρ‹ΠΌ библиомСтричСским ΠΈΠ½Π΄ΠΈΠΊΠ°Ρ‚ΠΎΡ€Π°ΠΌ, заявлСнным Π² Π£ΠΊΠ°Π·Π΅ ΠŸΡ€Π΅Π·ΠΈΠ΄Π΅Π½Ρ‚Π° β„–Β 599 ΠΎΡ‚ 7 мая 2012Β Π³. (ΡƒΠ²Π΅Π»ΠΈΡ‡Π΅Π½ΠΈΠ΅ Π΄ΠΎΠ»ΠΈ российских ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΉ Π² Web of Science Π΄ΠΎ 2,44% ΠΊ 2015Β Π³.), ΠΈ Π² Β«Π‘Ρ‚Ρ€Π°Ρ‚Π΅Π³ΠΈΠΈ развития мСдицинской Π½Π°ΡƒΠΊΠΈ Π΄ΠΎ 2025Β Π³.Β» Показано, Ρ‡Ρ‚ΠΎ глобальная Π½Π°ΡƒΠΊΠ°, Π² слоТившСйся структурС ΠΊΠΎΡ‚ΠΎΡ€ΠΎΠΉ Π½Π° биомСдицинскиС ΡΡ‚Π°Ρ‚ΡŒΠΈ приходится ΠΎΠΊΠΎΠ»ΠΎ 1/3 ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎΠ³ΠΎ ΠΌΠΈΡ€ΠΎΠ²ΠΎΠ³ΠΎ ΠΏΠΎΡ‚ΠΎΠΊΠ°, ставит ΠΏΠ΅Ρ€Π΅Π΄ российским мСдицинским сообщСством ΠΎΡ‡Π΅Π½ΡŒ ΡΠ»ΠΎΠΆΠ½ΡƒΡŽ Π·Π°Π΄Π°Ρ‡Ρƒ: ΡƒΠ΄Π²ΠΎΠΈΡ‚ΡŒ Π·Π° 3 Π³ΠΎΠ΄Π° число ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΉ, индСксируСмых Π² Web of Science. РассмотрСны ΠΏΠ΅Ρ€Π²ΠΎΠΎΡ‡Π΅Ρ€Π΅Π΄Π½Ρ‹Π΅ ΠΈ Π½Π΅ΠΎΠ±Ρ…ΠΎΠ΄ΠΈΠΌΡ‹Π΅ ΠΌΠ΅Ρ€Ρ‹ для выполнСния этой Π·Π°Π΄Π°Ρ‡ΠΈ.

    ΠΠΠΠ›Π˜Π— ΠŸΠ£Π‘Π›Π˜ΠšΠΠ¦Π˜ΠžΠΠΠžΠ“Πž ПОВОКА РАМН ЗА 2011 Π“. И ΠŸΠ•Π Π‘ΠŸΠ•ΠšΠ’Π˜Π’Π« Π£Π’Π•Π›Π˜Π§Π•ΠΠ˜Π― Π•Π“Πž ΠžΠ‘ΠͺΠ•ΠœΠžΠ’ И ΠΠ’Π’ΠžΠ Π˜Π’Π•Π’ΠΠžΠ‘Π’Π˜ Π’ Π‘ΠžΠžΠ’Π’Π•Π’Π‘Π’Π’Π˜Π˜ Π‘ Π˜ΠΠ”Π˜ΠšΠΠ’ΠžΠ ΠΠœΠ˜ Β«ΠŸΠ ΠžΠ“Π ΠΠœΠœΠ« Π€Π£ΠΠ”ΠΠœΠ•ΠΠ’ΠΠ›Π¬ΠΠ«Π₯ НАУЧНЫΠ₯ Π˜Π‘Π‘Π›Π•Π”ΠžΠ’ΠΠΠ˜Π™ Π“ΠžΠ‘ΠΠšΠΠ”Π•ΠœΠ˜Π™ НА 2013–2020 Π“Π“.Β»

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    The scope of bibliometric research is focused on academic output of the Russian Academy of Medical Sciences (RAMS) in 2011 by analyzing the data extracted from the Web of Science database and InCites application Research Performance Profile of RAMS. Using these analytical tools trends in dynamics of publications and citing of the RAMS researchers were calculated and the level of scientific output in some biomedical subject areas was estimated. Studies revealed the great importance of international collaboration and international coauthorship for RAMS in producing papers published in established scholarly journals. Basic metrics of scientific performance that should be required to achieve the goals declared in the recent governmental policy papers were measured for RAMS institutions as well. Another problem investigated in this research is the problem of low citedness of RAMS journal papers indexed in WoS. Factors and reasons influenced on low citedness were discovered In conclusion authors set out priorities and reasonable goal-oriented efforts to achieve better results in publication activity.Β Π’ Ρ€Π°Π±ΠΎΡ‚Π΅ прСдставлСно библиомСтричСскоС исслСдованиС ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎΠ³ΠΎ ΠΏΠΎΡ‚ΠΎΠΊΠ° ΡƒΡ‡Π΅Π½Ρ‹Ρ… Российской Π°ΠΊΠ°Π΄Π΅ΠΌΠΈΠΈ мСдицинских Π½Π°ΡƒΠΊ (РАМН) Π² ΠΌΠ΅ΠΆΠ΄ΡƒΠ½Π°Ρ€ΠΎΠ΄Π½ΠΎΠΉ Π°Π½Π°Π»ΠΈΡ‚ΠΈΠΊΠΎ-библиографичСской систСмС Web of Science Π·Π° 2011Β Π³. Π’ Ρ€Π°ΠΌΠΊΠ°Ρ… исслСдования Π±Ρ‹Π» ΠΈΠ·ΡƒΡ‡Π΅Π½ ΠΏΡ€ΠΎΡ„ΠΈΠ»ΡŒ Π½Π°ΡƒΡ‡Π½ΠΎΠΉ продуктивности РАМН Π² аналитичСском ΠΏΡ€ΠΈΠ»ΠΎΠΆΠ΅Π½ΠΈΠΈ InCites. Π’Ρ‹ΠΏΠΎΠ»Π½Π΅Π½ Π°Π½Π°Π»ΠΈΠ· Π΄ΠΈΠ½Π°ΠΌΠΈΠΊΠΈ ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎΠΉ активности ΠΈ цитируСмости ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΉ сотрудников институтов РАМН, ΠΎΡ†Π΅Π½Π΅Π½ ΡƒΡ€ΠΎΠ²Π΅Π½ΡŒ Π½Π°ΡƒΡ‡Π½ΠΎΠΉ ΠΏΡ€ΠΎΠΈΠ·Π²ΠΎΠ΄ΠΈΡ‚Π΅Π»ΡŒΠ½ΠΎΡΡ‚ΠΈ ΠΈ продуктивности ΠΎΡ‚Π΄Π΅Π»ΡŒΠ½Ρ‹Ρ… ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Ρ‚Π΅Π»ΡŒΡΠΊΠΈΡ… Π½Π°ΠΏΡ€Π°Π²Π»Π΅Π½ΠΈΠΉ, Π° Ρ‚Π°ΠΊΠΆΠ΅ ΡΡ„Ρ„Π΅ΠΊΡ‚ΠΈΠ²Π½ΠΎΡΡ‚ΡŒ ΠΌΠ΅ΠΆΠ΄ΡƒΠ½Π°Ρ€ΠΎΠ΄Π½ΠΎΠ³ΠΎ Π½Π°ΡƒΡ‡Π½ΠΎΠ³ΠΎ сотрудничСства. Π”Π°Π½Π° ΠΎΡ†Π΅Π½ΠΊΠ° соотвСтствия Ρ€Π΅Π°Π»ΡŒΠ½Ρ‹Ρ… ΠΏΠΎΠΊΠ°Π·Π°Ρ‚Π΅Π»Π΅ΠΉ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚ΠΈΠ²Π½ΠΎΡΡ‚ΠΈ Π½Π°ΡƒΡ‡Π½ΠΎΠΉ Π΄Π΅ΡΡ‚Π΅Π»ΡŒΠ½ΠΎΡΡ‚ΠΈ РАМН ΠΏΡ€ΠΎΠ³Π½ΠΎΠ·Π½Ρ‹ΠΌ значСниям ΠΈΠ½Π΄ΠΈΠΊΠ°Ρ‚ΠΎΡ€ΠΎΠ² ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎΠΉ активности, заявлСнным Π² рядС ΠΏΡ€ΠΎΠ³Ρ€Π°ΠΌΠΌΠ½Ρ‹Ρ… ΠΏΡ€Π°Π²ΠΈΡ‚Π΅Π»ΡŒΡΡ‚Π²Π΅Π½Π½Ρ‹Ρ… Π΄ΠΎΠΊΡƒΠΌΠ΅Π½Ρ‚ΠΎΠ². ИсслСдована ΠΏΡ€ΠΎΠ±Π»Π΅ΠΌΠ° ΠΎΠ±Ρ‰Π΅ΠΉ Π½ΠΈΠ·ΠΊΠΎΠΉ цитируСмости ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΉ исслСдоватСлСй ΠΈΠ· РАМН ΠΈ осущСствлСнн Π°Π½Π°Π»ΠΈΠ· Ρ„Π°ΠΊΡ‚ΠΎΡ€ΠΎΠ², Π²Π»ΠΈΡΡŽΡ‰ΠΈΡ… Π½Π° ΡƒΡ€ΠΎΠ²Π΅Π½ΡŒ цитируСмости отСчСствСнных Ρ€Π°Π±ΠΎΡ‚ Π² области Π±ΠΈΠΎΠΌΠ΅Π΄ΠΈΡ†ΠΈΠ½Ρ‹. Π’ Π·Π°ΠΊΠ»ΡŽΡ‡Π΅Π½ΠΈΠΈ Π΄Π°ΡŽΡ‚ΡΡ Ρ€Π΅ΠΊΠΎΠΌΠ΅Π½Π΄Π°Ρ†ΠΈΠΈ ΠΏΠΎ росту ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎΠΉ ΠΈ Ρ†ΠΈΡ‚Π°Ρ‚Π½ΠΎΠΉ активности для ΠΏΡƒΠ±Π»ΠΈΠΊΠ°Ρ†ΠΈΠΉ РАМН.Β 

    Effects of rapid prey evolution on predator-prey cycles

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    We study the qualitative properties of population cycles in a predator-prey system where genetic variability allows contemporary rapid evolution of the prey. Previous numerical studies have found that prey evolution in response to changing predation risk can have major quantitative and qualitative effects on predator-prey cycles, including: (i) large increases in cycle period, (ii) changes in phase relations (so that predator and prey are cycling exactly out of phase, rather than the classical quarter-period phase lag), and (iii) "cryptic" cycles in which total prey density remains nearly constant while predator density and prey traits cycle. Here we focus on a chemostat model motivated by our experimental system [Fussmann et al. 2000,Yoshida et al. 2003] with algae (prey) and rotifers (predators), in which the prey exhibit rapid evolution in their level of defense against predation. We show that the effects of rapid prey evolution are robust and general, and furthermore that they occur in a specific but biologically relevant region of parameter space: when traits that greatly reduce predation risk are relatively cheap (in terms of reductions in other fitness components), when there is coexistence between the two prey types and the predator, and when the interaction between predators and undefended prey alone would produce cycles. Because defense has been shown to be inexpensive, even cost-free, in a number of systems [Andersson and Levin 1999, Gagneux et al. 2006,Yoshida et al. 2004], our discoveries may well be reproduced in other model systems, and in nature. Finally, some of our key results are extended to a general model in which functional forms for the predation rate and prey birth rate are not specified.Comment: 35 pages, 8 figure

    Stability of Spatial Optical Solitons

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    We present a brief overview of the basic concepts of the soliton stability theory and discuss some characteristic examples of the instability-induced soliton dynamics, in application to spatial optical solitons described by the NLS-type nonlinear models and their generalizations. In particular, we demonstrate that the soliton internal modes are responsible for the appearance of the soliton instability, and outline an analytical approach based on a multi-scale asymptotic technique that allows to analyze the soliton dynamics near the marginal stability point. We also discuss some results of the rigorous linear stability analysis of fundamental solitary waves and nonlinear impurity modes. Finally, we demonstrate that multi-hump vector solitary waves may become stable in some nonlinear models, and discuss the examples of stable (1+1)-dimensional composite solitons and (2+1)-dimensional dipole-mode solitons in a model of two incoherently interacting optical beams.Comment: 34 pages, 9 figures; to be published in: "Spatial Optical Solitons", Eds. W. Torruellas and S. Trillo (Springer, New York

    Stability of trapped Bose-Einstein condensates

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    In three-dimensional trapped Bose-Einstein condensate (BEC), described by the time-dependent Gross-Pitaevskii-Ginzburg equation, we study the effect of initial conditions on stability using a Gaussian variational approach and exact numerical simulations. We also discuss the validity of the criterion for stability suggested by Vakhitov and Kolokolov. The maximum initial chirp (initial focusing defocusing of cloud) that can lead a stable condensate to collapse even before the number of atoms reaches its critical limit is obtained for several specific cases. When we consider two- and three-body nonlinear terms, with negative cubic and positive quintic terms, we have the conditions for the existence of two phases in the condensate. In this case, the magnitude of the oscillations between the two phases are studied considering sufficient large initial chirps. The occurrence of collapse in a BEC with repulsive two-body interaction is also shown to be possible.Comment: 15 pages, 11 figure

    Demonstration of the temporal matter-wave Talbot effect for trapped matter waves

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    We demonstrate the temporal Talbot effect for trapped matter waves using ultracold atoms in an optical lattice. We investigate the phase evolution of an array of essentially non-interacting matter waves and observe matter-wave collapse and revival in the form of a Talbot interference pattern. By using long expansion times, we image momentum space with sub-recoil resolution, allowing us to observe fractional Talbot fringes up to 10th order.Comment: 17 pages, 7 figure
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