275 research outputs found

    АналитичСский ΠΏΠΎΠ΄Ρ…ΠΎΠ΄ ΠΊ Π²Ρ‹Π±ΠΎΡ€Ρƒ Ρ‚ΠΎΠΏΠΎΠ»ΠΎΠ³ΠΈΠΈ нСйросСтСй ΠΏΡ€ΠΈ Ρ€Π΅ΡˆΠ΅Π½ΠΈΠΈ ΠΏΡ€ΠΈΠΊΠ»Π°Π΄Π½Ρ‹Ρ… Π·Π°Π΄Π°Ρ‡

    Get PDF
    На основі Ρ€ΠΎΠ·Ρ€ΠΎΠ±Π»Π΅Π½ΠΎΠ³ΠΎ рСляційного класифікатора Π·Π°ΠΏΡ€ΠΎΠΏΠΎΠ½ΠΎΠ²Π°Π½ΠΈΠΉ ΡƒΠ½Ρ–Π²Π΅Ρ€ΡΠ°Π»ΡŒΠ½ΠΈΠΉ ΠΏΡ–Π΄Ρ…Ρ–Π΄ Π΄ΠΎ Π²ΠΈΠ±ΠΎΡ€Ρƒ Ρ‚ΠΎΠΏΠΎΠ»ΠΎΠ³Ρ–Ρ— Π½Π΅ΠΉΡ€ΠΎΠΌΠ΅Ρ€Π΅ΠΆ, Ρ‰ΠΎ Π·Π°Π΄ΠΎΠ²ΠΎΠ»ΡŒΠ½ΡΡŽΡ‚ΡŒ критСріям Π²ΠΈΡ€Ρ–ΡˆΠ΅Π½Π½Ρ ΠΏΡ€ΠΈΠΊΠ»Π°Π΄Π½ΠΎΡ— ΠΏΡ€ΠΎΠ±Π»Π΅ΠΌΠΈ / Π·Π°Π΄Π°Ρ‡Ρ–. Π—Π°ΠΏΡ€ΠΎΠΏΠΎΠ½ΠΎΠ²Π°Π½ΠΎ Π°Π³Π΅Π½Ρ‚Π½ΠΎ-ΠΎΡ€Ρ–Ρ”Π½Ρ‚ΠΎΠ²Π°Π½ΠΈΠΉ ΠΏΡ–Π΄Ρ…Ρ–Π΄ Π΄ΠΎ Π²ΠΈΠ±ΠΎΡ€Ρƒ Ρ‚ΠΎΠΏΠΎΠ»ΠΎΠ³Ρ–Ρ— Π½Π΅ΠΉΡ€ΠΎΠΌΠ΅Ρ€Π΅ΠΆΡ–. ΠžΠ±Π³Ρ€ΡƒΠ½Ρ‚ΠΎΠ²Π°Π½Π° Π»ΠΎΠ³Ρ–Ρ‡Π½Π° схСма ΠΏΠΎΠ΅Ρ‚Π°ΠΏΠ½ΠΎΠ³ΠΎ синтСзу ΡˆΡ‚ΡƒΡ‡Π½ΠΈΡ… Π½Π΅ΠΉΡ€ΠΎΠΌΠ΅Ρ€Π΅ΠΆ, Ρ‰ΠΎ дозволяє Π°Π²Ρ‚ΠΎΠΌΠ°Ρ‚ΠΈΠ·ΡƒΠ²Π°Ρ‚ΠΈ ΠΏΡ€ΠΎΡ†Π΅Π΄ΡƒΡ€Ρƒ ΠΏΠΎΡˆΡƒΠΊΡƒ Π½Π΅ΠΉΡ€ΠΎΠΌΠ΅Ρ€Π΅ΠΆΡ–, яка Π·Π°Π±Π΅Π·ΠΏΠ΅Ρ‡ΡƒΡ” обслуговування Π²ΠΈΠΌΠΎΠ³ ΠΏΡ€ΠΈΠΊΠ»Π°Π΄Π½ΠΎΡ— Π·Π°Π΄Π°Ρ‡Ρ–.The universal approach of the NeuroNets’ topology choice based on the created relative classifier and satisfied of the applied problem (or task) service’s criteria. The agent-oriented approach to choice the neuro-net’s topology is proposed. The logic scheme of the Artificial NeuroNet’s step-by-step synthesis is based and allows to automatizate the choice of the best NeuroNet for applied problem.На основС Ρ€Π°Π·Ρ€Π°Π±ΠΎΡ‚Π°Π½Π½ΠΎΠ³ΠΎ рСляционного классификатора ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½ ΡƒΠ½ΠΈΠ²Π΅Ρ€ΡΠ°Π»ΡŒΠ½Ρ‹ΠΉ ΠΏΠΎΠ΄Ρ…ΠΎΠ΄ ΠΊ Π²Ρ‹Π±ΠΎΡ€Ρƒ Ρ‚ΠΎΠΏΠΎΠ»ΠΎΠ³ΠΈΠΈ нСйросСтСй, ΡƒΠ΄ΠΎΠ²Π»Π΅Ρ‚Π²ΠΎΡ€ΡΡŽΡ‰ΠΈΡ… критСриям обслуТиваСмости ΠΏΡ€ΠΈΠΊΠ»Π°Π΄Π½ΠΎΠΉ ΠΏΡ€ΠΎΠ±Π»Π΅ΠΌΡ‹/Π·Π°Π΄Π°Ρ‡ΠΈ. ΠŸΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½ Π°Π³Π΅Π½Ρ‚Π½ΠΎ-ΠΎΡ€ΠΈΠ΅Π½Ρ‚ΠΈΡ€ΠΎΠ²Π°Π½Π½Ρ‹ΠΉ ΠΏΠΎΠ΄Ρ…ΠΎΠ΄ ΠΊ Π²Ρ‹Π±ΠΎΡ€Ρƒ Ρ‚ΠΎΠΏΠΎΠ»ΠΎΠ³ΠΈΠΈ нСйросСти. Обоснована логичСская схСма поэтапного синтСза искусствСнных нСйросСтСй, ΠΏΠΎΠ·Π²ΠΎΠ»ΡΡŽΡ‰Π°Ρ Π°Π²Ρ‚ΠΎΠΌΠ°Ρ‚ΠΈΠ·ΠΈΡ€ΠΎΠ²Π°Ρ‚ΡŒ ΠΏΡ€ΠΎΡ†Π΅Π΄ΡƒΡ€Ρƒ поиска нСйросСти, ΠΎΠ±Π΅ΡΠΏΠ΅Ρ‡ΠΈΠ²Π°ΡŽΡ‰Π΅ΠΉ обслуТиваниС Ρ‚Ρ€Π΅Π±ΠΎΠ²Π°Π½ΠΈΠΉ ΠΏΡ€ΠΈΠΊΠ»Π°Π΄Π½ΠΎΠΉ Π·Π°Π΄Π°Ρ‡ΠΈ

    A novel-type luciferin from Siberian luminous earthworm Fridericia heliota : structure elucidation by spectral studies and total synthesis

    Get PDF
    Author Posting. Β© The Author(s), 2014. This is the author's version of the work. It is posted here by permission of Wiley-VCH Verlag GmbH & Co for personal use, not for redistribution. The definitive version was published in Angewandte Chemie International Edition 53 (2014): 5566–5568, doi:10.1002/anie.201400529.We report structure elucidation and synthesis of the luciferin from the recently discovered luminous earthworm Fridericia heliota. This luciferin represents a key component of a novel ATP-dependent bioluminescence system. The UV, fluorescence, NMR and HRMS spectral studies were performed on 5 mkg of the isolated substance, and gave four isomeric structures, conforming with spectral data. These isomers were chemically synthesized and one of them was found to produce light in the reaction with a protein extract from Fridericia. The novel luciferin was found to have an unusual deeply modified peptidic nature, implying an unprecedented mechanism of action.We acknowledge support from the Program of the Government of the Russian Federation β€œMeasures to attract leading scientists to Russian educational institutions” (grant no. 11. G34.31.0058), the programs MCB RAS, President of the Russian Federation β€œLeading science school” (grant 3951.2012.4) and the Russian Foundation for Basic Research (grant 14-03-01015). B.M.S. was supported by a stipend from the Program of the President of the Russian Federation.2015-04-1

    Π­ΠΊΡΠΏΠ΅Ρ€ΠΈΠΌΠ΅Π½Ρ‚Π°Π»ΡŒΠ½ΠΎΠ΅ исслСдованиС Π½Π΅ΠΉΡ€ΠΎ-Ρ„Π°Π·Π·ΠΈ ΠΌΠΎΠ΄Π΅Π»ΠΈ согласования ΠΎΠ±ΡŠΠ΅ΠΊΡ‚ΠΎΠ² производства ΠΈ срСдств упорядочивания срСды

    Get PDF
    ΠŸΡ€ΠΈΠ²Π΅Π΄Π΅Π½Ρ– Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚ΠΈ Π΅ΠΊΡΠΏΠ΅Ρ€ΠΈΠΌΠ΅Π½Ρ‚Π°Π»ΡŒΠ½ΠΎΠ³ΠΎ дослідТСння Π·Π°ΠΏΡ€ΠΎΠΏΠΎΠ½ΠΎΠ²Π°Π½ΠΎΡ— Π½Π΅ΠΉΡ€ΠΎ-Ρ„Π°Π·Π·Ρ– ΠΌΠΎΠ΄Π΅Π»Ρ– узгодТСння об’єктів Π²ΠΈΡ€ΠΎΠ±Π½ΠΈΡ†Ρ‚Π²Π° Ρ– засобів упорядкування сСрСдовища, які засвідчили ΠΏΠ΅Ρ€Π΅Π²Π°Π³ΠΈ використання Π½Π΅ΠΉΡ€ΠΎ-Ρ„Π°Π·Π·Ρ– Ρ‚Π΅Ρ…Π½ΠΎΠ»ΠΎΠ³Ρ–ΠΉ для розв’язання слабкоформалізованих Π·Π°Π΄Π°Ρ‡ прийняття Ρ€Ρ–ΡˆΠ΅Π½ΡŒ Π· Π΅Π»Π΅ΠΌΠ΅Π½Ρ‚Π°ΠΌΠΈ нСчіткості Ρ– лінгвістичної нСвизначності.Results of experimental research of neuro-fuzzy model for manufacture objects and environment ordering tools coordination are reported. Results testify the advantages of neuro-fuzzy technologies usage for solving weakly fomalized of decision-makin problems with elements of an illegibility and linguistic uncertainty.ΠŸΡ€ΠΈΠ²Π΅Π΄Π΅Π½Ρ‹ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Ρ‹ ΡΠΊΡΠΏΠ΅Ρ€ΠΈΠΌΠ΅Π½Ρ‚Π°Π»ΡŒΠ½ΠΎΠ³ΠΎ исслСдования Π½Π΅ΠΉΡ€ΠΎ-Ρ„Π°Π·Π·ΠΈ ΠΌΠΎΠ΄Π΅Π»ΠΈ согласования ΠΎΠ±ΡŠΠ΅ΠΊΡ‚ΠΎΠ² производства ΠΈ срСдств упорядочивания срСды, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ ΡΠ²ΠΈΠ΄Π΅Ρ‚Π΅Π»ΡŒΡΡ‚Π²ΡƒΡŽΡ‚ ΠΎ прСимущСствах использования Π½Π΅ΠΉΡ€ΠΎ-Ρ„Π°Π·Π·ΠΈ Ρ‚Π΅Ρ…Π½ΠΎΠ»ΠΎΠ³ΠΈΠΉ для Ρ€Π΅ΡˆΠ΅Π½ΠΈΡ слабоформализованных Π·Π°Π΄Π°Ρ‡ принятия Ρ€Π΅ΡˆΠ΅Π½ΠΈΠΉ с элСмСнтами нСчСткости ΠΈ лингвистичСской нСопрСдСлСнности

    АгСнтно-ΠΎΡ€ΠΈΠ΅Π½Ρ‚ΠΈΡ€ΠΎΠ²Π°Π½Π½Ρ‹ΠΉ ΠΏΠΎΠ΄Ρ…ΠΎΠ΄ ΠΊ Ρ€Π΅ΡˆΠ΅Π½ΠΈΡŽ логистичСских Π·Π°Π΄Π°Ρ‡ диспСтчСризации ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»ΡŒΠ½Ρ‹Ρ… ΠΏΠΎΡ‚ΠΎΠΊΠΎΠ²

    Get PDF
    Π’ Π΄Π°Π½Ρ–ΠΉ Ρ€ΠΎΠ±ΠΎΡ‚Ρ– Ρ€ΠΎΠ·Π³Π»ΡΠ΄Π°Ρ”Ρ‚ΡŒΡΡ клас логістичних Π·Π°Π΄Π°Ρ‡ диспСтчСризації ΠΌΠ°Ρ‚Π΅Ρ€Ρ–Π°Π»ΡŒΠ½ΠΈΡ… ΠΏΠΎΡ‚ΠΎΠΊΡ–Π². Π”Π°Π½ΠΈΠΉ клас Π·Π°Π΄Π°Ρ‡ ΠΌΠ°Ρ” ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΈ Π²ΠΈΡ€Ρ–ΡˆΠ΅Π½Π½Ρ Ρ–Π· застосуванням Π²Π΅Π»ΠΈΠΊΠΎΡ— ΠΊΡ–Π»ΡŒΠΊΠΎΡΡ‚Ρ– ΠΏΡ–Π΄Ρ…ΠΎΠ΄Ρ–Π² Π· залучСнням знань Ρ–Π· Ρ€Ρ–Π·Π½ΠΈΡ… областСй ΠΌΠ°Ρ‚Π΅ΠΌΠ°Ρ‚ΠΈΠΊΠΈ для ΠΏΠΎΠ±ΡƒΠ΄ΠΎΠ²ΠΈ ΠΌΠ°Ρ‚Π΅ΠΌΠ°Ρ‚ΠΈΡ‡Π½ΠΈΡ… ΠΌΠΎΠ΄Π΅Π»Π΅ΠΉ логістичних систСм. Π”Π°Π½Π° Ρ€ΠΎΠ±ΠΎΡ‚Π° ΠΏΡ€ΠΎΠΏΠΎΠ½ΡƒΡ” Ρ– ΠΎΠ±Π³Ρ€ΡƒΠ½Ρ‚ΠΎΠ²ΡƒΡ” використання Π½ΠΎΠ²Ρ–Ρ‚Π½ΡŒΠΎΠ³ΠΎ Π°Π³Π΅Π½Ρ‚Π½ΠΎ-ΠΎΡ€Ρ–Ρ”Π½Ρ‚ΠΎΠ²Π°Π½ΠΎΠ³ΠΎ ΠΏΡ–Π΄Ρ…ΠΎΠ΄Ρƒ для Π²ΠΈΡ€Ρ–ΡˆΠ΅Π½Π½Ρ Π²ΠΊΠ°Π·Π°Π½ΠΎΠ³ΠΎ Ρ‚ΠΈΠΏΡƒ Π·Π°Π΄Π°Ρ‡, Π²ΠΏΠ΅Ρ€ΡˆΠ΅ Π·Π°ΠΏΡ€ΠΎΠΏΠΎΠ½ΠΎΠ²Π°Π½ΠΎΠ³ΠΎ для Π²ΠΈΡ€Ρ–ΡˆΠ΅Π½Π½Ρ Π·Π°Π΄Π°Ρ‡ ΠΏΠΎΠ±ΡƒΠ΄ΠΎΠ²ΠΈ СкспСртних систСм ΠΏΡ–Π΄Ρ‚Ρ€ΠΈΠΌΠΊΠΈ прийняття Ρ€Ρ–ΡˆΠ΅Π½ΡŒ Ρ‚Π° ΡˆΡ‚ΡƒΡ‡Π½ΠΎΠ³ΠΎ Ρ–Π½Ρ‚Π΅Π»Π΅ΠΊΡ‚Ρƒ.The article discusses class of problems related to material flows dispatching logistic. This class of problems has solutions that involve large quantity of approaches and methods taken from different branches of mathematics for creating models of studied systems. Current work offers using modern agent-oriented approach to solving such kind of engineering problems that was firstly used for creating expert decision making support systems and solving artificial intelligence problems.Π’ Π΄Π°Π½Π½ΠΎΠΉ Ρ€Π°Π±ΠΎΡ‚Π΅ рассматриваСтся класс логистичСских Π·Π°Π΄Π°Ρ‡ диспСтчСризации ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»ΡŒΠ½Ρ‹Ρ… ΠΏΠΎΡ‚ΠΎΠΊΠΎΠ². Π”Π°Π½Π½Ρ‹ΠΉ класс Π·Π°Π΄Π°Ρ‡ ΠΈΠΌΠ΅Π΅Ρ‚ ΠΌΠ΅Ρ‚ΠΎΠ΄Ρ‹ Ρ€Π΅ΡˆΠ΅Π½ΠΈΡ с ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ΠΌ большого количСства ΠΏΠΎΠ΄Ρ…ΠΎΠ΄ΠΎΠ² с ΠΏΡ€ΠΈΠ²Π»Π΅Ρ‡Π΅Π½ΠΈΠ΅ΠΌ Π·Π½Π°Π½ΠΈΠΉ ΠΈΠ· Ρ€Π°Π·Π½Ρ‹Ρ… областСй ΠΌΠ°Ρ‚Π΅ΠΌΠ°Ρ‚ΠΈΠΊΠΈ, ΠΈΡΠΏΠΎΠ»ΡŒΠ·ΡƒΠ΅ΠΌΡ‹Ρ… для построСния матСматичСских ΠΌΠΎΠ΄Π΅Π»Π΅ΠΉ логистичСских систСм. Π’ Π΄Π°Π½Π½ΠΎΠΉ Ρ€Π°Π±ΠΎΡ‚Π΅ ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½ΠΎ ΠΈ обосновано использованиС Π½ΠΎΠ²ΠΎΠ³ΠΎ Π°Π³Π΅Π½Ρ‚Π½ΠΎ-ΠΎΡ€ΠΈΠ΅Π½Ρ‚ΠΈΡ€ΠΎΠ²Π°Π½Π½ΠΎΠ³ΠΎ ΠΏΠΎΠ΄Ρ…ΠΎΠ΄Π° для Ρ€Π΅ΡˆΠ΅Π½ΠΈΡ ΡƒΠΊΠ°Π·Π°Π½Π½ΠΎΠ³ΠΎ Ρ‚ΠΈΠΏΠ° Π·Π°Π΄Π°Ρ‡, Π²ΠΏΠ΅Ρ€Π²Ρ‹Π΅ ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½Π½ΠΎΠ³ΠΎ для Ρ€Π΅ΡˆΠ΅Π½ΠΈΡ Π·Π°Π΄Π°Ρ‡ построСния экспСртных систСм ΠΏΠΎΠ΄Π΄Π΅Ρ€ΠΆΠΊΠΈ принятия Ρ€Π΅ΡˆΠ΅Π½ΠΈΠΉ ΠΈ искусствСнного ΠΈΠ½Ρ‚Π΅Π»Π»Π΅ΠΊΡ‚Π°

    Π£ΡΠΎΠ²Π΅Ρ€ΡˆΠ΅Π½ΡΡ‚Π²ΠΎΠ²Π°Π½ΠΈΠ΅ ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠ² ΠΈ ΠΈΠ½ΡΡ‚Ρ€ΡƒΠΌΠ΅Π½Ρ‚Π°Π»ΡŒΠ½Ρ‹Ρ… срСдств создания АУМ с использованиСм Internet-Ρ‚Π΅Ρ…Π½ΠΎΠ»ΠΎΠ³ΠΈΠΉ

    Get PDF
    НавСдСно Π°Π½Π°Π»Ρ–Ρ‚ΠΈΡ‡Π½ΠΈΠΉ огляд Ρ–ΡΠ½ΡƒΡŽΡ‡ΠΈΡ… ΠΌΠ΅Ρ‚ΠΎΠ΄Ρ–Π² Ρ‚Π° Ρ–Π½ΡΡ‚Ρ€ΡƒΠΌΠ΅Π½Ρ‚Π°Π»ΡŒΠ½ΠΈΡ… засобів створСння АУМ. Π—Π°ΠΏΡ€ΠΎΠΏΠΎΠ½ΠΎΠ²Π°Π½ΠΎ ΠΏΡ€ΠΎΠ³Ρ€Π°ΠΌΠ½ΠΎ Ρ€Π΅Π°Π»Ρ–Π·ΠΎΠ²Π°Π½ΠΈΠΉ спСціалізований Π΄ΠΎΠ΄Π°Ρ‚ΠΎΠΊ, ΠΎΡ€Ρ–Ρ”Π½Ρ‚ΠΎΠ²Π°Π½ΠΈΠΉ Π½Π° підвищСння СфСктивності Ρ„ΡƒΠ½ΠΊΡ†Ρ–ΠΉ HTML-рСдагування Ρ– управління змістовими об’єктами Π΄Π°Π½ΠΈΡ… Π² АУМ Ρ‚Π° Ρ–Π½ΡˆΠΈΡ… ΠΏΠΎΠ΄Ρ–Π±Π½ΠΈΡ… HTML-ΠΎΡ€Ρ–Ρ”Π½Ρ‚ΠΎΠ²Π°Π½ΠΈΡ… систСмах.Analytical overview of existing methods and instruments for AEP creation is given. Programmatically implemented specialized application for increasing effectiveness of HTML-editing and content objects management functions in AEP and other HTML-oriented systems is proposed.ΠŸΡ€ΠΈΠ²Π΅Π΄Π΅Π½ аналитичСский ΠΎΠ±Π·ΠΎΡ€ ΡΡƒΡ‰Π΅ΡΡ‚Π²ΡƒΡŽΡ‰ΠΈΡ… ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠ² ΠΈ ΠΈΠ½ΡΡ‚Ρ€ΡƒΠΌΠ΅Π½Ρ‚Π°Π»ΡŒΠ½Ρ‹Ρ… срСдств создания АУМ. ΠŸΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½ΠΎ ΠΏΡ€ΠΎΠ³Ρ€Π°ΠΌΠΌΠ½ΠΎ Ρ€Π΅Π°Π»ΠΈΠ·ΠΎΠ²Π°Π½Π½ΠΎΠ΅ спСциализированноС ΠΏΡ€ΠΈΠ»ΠΎΠΆΠ΅Π½ΠΈΠ΅, ΠΎΡ€ΠΈΠ΅Π½Ρ‚ΠΈΡ€ΠΎΠ²Π°Π½Π½ΠΎΠ΅ Π½Π° ΠΏΠΎΠ²Ρ‹ΡˆΠ΅Π½ΠΈΠ΅ эффСктивности Ρ„ΡƒΠ½ΠΊΡ†ΠΈΠΉ HTML-рСдактирования ΠΈ управлСния смысловыми ΠΎΠ±ΡŠΠ΅ΠΊΡ‚Π°ΠΌΠΈ Π΄Π°Π½Π½Ρ‹Ρ… Π² АУМ ΠΈ Π΄Ρ€ΡƒΠ³ΠΈΡ… ΠΏΠΎΠ΄ΠΎΠ±Π½Ρ‹Ρ… HTML-ΠΎΡ€ΠΈΠ΅Π½Ρ‚ΠΈΡ€ΠΎΠ²Π°Π½Π½Ρ‹Ρ… систСмах

    Chirped pulse Raman amplification in warm plasma: towards controlling saturation

    Get PDF
    Stimulated Raman backscattering in plasma is potentially an efficient method of amplifying laser pulses to reach exawatt powers because plasma is fully broken down and withstands extremely high electric fields. Plasma also has unique nonlinear optical properties that allow simultaneous compression of optical pulses to ultra-short durations. However, current measured efficiencies are limited to several percent. Here we investigate Raman amplification of short duration seed pulses with different chirp rates using a chirped pump pulse in a preformed plasma waveguide. We identify electron trapping and wavebreaking as the main saturation mechanisms, which lead to spectral broadening and gain saturation when the seed reaches several millijoules for durations of 10's - 100's fs for 250 ps, 800 nm chirped pump pulses. We show that this prevents access to the nonlinear regime and limits the efficiency, and interpret the experimental results using slowly-varying-amplitude, current-averaged particle-in-cell simulations. We also propose methods for achieving higher efficiencies.close0

    Transcriptome‐based phylogeny of endemic Lake Baikal amphipod species flock: fast speciation accompanied by frequent episodes of positive selection

    Full text link
    Endemic species flocks inhabiting ancient lakes, oceanic islands and other long‐lived isolated habitats are often interpreted as adaptive radiations. Yet molecular evidence for directional selection during species flocks radiation is scarce. Using partial transcriptomes of 64 species of Lake Baikal (Siberia, Russia) endemic amphipods and two nonendemic outgroups, we report a revised phylogeny of this species flock and analyse evidence for positive selection within the endemic lineages. We confirm two independent invasions of amphipods into Baikal and demonstrate that several morphological features of Baikal amphipods, such as body armour and reduction in appendages and sensory organs, evolved in several lineages in parallel. Radiation of Baikal amphipods has been characterized by short phylogenetic branches and frequent episodes of positive selection which tended to be more frequent in the early phase of the second invasion of amphipods into Baikal when the most intensive diversification occurred. Notably, signatures of positive selection are frequent in genes encoding mitochondrial membrane proteins with electron transfer chain and ATP synthesis functionality. In particular, subunits of both the membrane and substrate‐level ATP synthases show evidence of positive selection in the plankton species Macrohectopus branickii, possibly indicating adaptation to active plankton lifestyle and to survival under conditions of low temperature and high hydrostatic pressures known to affect membranes functioning. Other functional categories represented among genes likely to be under positive selection include Ca‐binding muscle‐related proteins, possibly indicating adaptation to Ca‐deficient low mineralization Baikal waters.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/136009/1/mec13927.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/136009/2/mec13927_am.pd
    • …
    corecore