997 resultados para 28-273


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In studying sexual attraction in gammarids of the group pulex, it has seemed necessary to dissociate the processes of moulting and ovogenesis in order to recognize their respective effects on this phenomenon. For this purpose a synthetic hormone, ecdysterone, was utilized. In the first instance the author followed the action of the hormone on isolated females in vitellogenesis. It was proved that the behaviour of Gammarus pulex and Gammarus fossarum vis-a-vis the ecdysterone used proves to be very close to that of isopods that was observed in Orchestia gammarellus in earlier research. Although they were in vitellogenesis, the females saw their intermoult cycle shortened.

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The ciliated protozoan Chilodonella cyprini is described. Chilodon parasitizes the body, gills and fins of fishes. The infusoria produce irritation of the integument and strengthened mucous secretion. The sparse knowledsge of the ecology of chilodon is summarised and some advice on the struggle against cholodoniasis in carp given.

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The rainfall regime and the karstic nature of the subsoil determines the alternation of a period of flow and a period of drought for a large number of Mediterranean streams. Amongst this type of stream it is possible to distinguish temporary streams, characterised by a period of flow for several months permitting the establishment of the principal groups of aquatic insects; and ephemeral streams whose very brief period of flow permits the establishment of a community reduced to a few species of Diptera. This paper aims to study the structure of the communities which colonise this particular type of stream and the ecology of the principal species which constitute these communities. Four French temporary streams were examined and temperature regimes, dissolved oxygen, calcium and magnesium measured. Samples of fauna were taken regularly and the biotic composition established. The analysis of similarities between the three permanent streams are discussed and compared with permanent streams.

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This partial translation of the original paper provides morphological observations on the fungus Spirospora paradoxa. Illustrations are included here.

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The lowest T = 2 states have been identified and studied in the nuclei 12C, 12B, 20F and and 28Al. The first two of these were produced in the reactions 14C(p,t)12C and 14C (p,3He)12B, at 50.5 and 63.4 MeV incident proton energy respectively, at the Oak Ridge National Laboratory. The T = 2 states in 20F and 28Al were observed in (3He,p) reactions at 12-MeV incident energy, with the Caltech Tandem accelerator.

The results for the four nuclei studied are summarized below:

(1) 12C: the lowest T = 2 state was located at an excitation energy of 27595 ± 20 keV, and has a width less than 35 keV.

(2) 12B: the lowest T = 2 state was found at an excitation energy of 12710 ± 20 keV. The width was determined to be less than 54 keV and the spin and parity were confirmed to be 0+. A second 12B state (or doublet) was observed at an excitation energy of 14860 ± 30 keV with a width (if the group corresponds to a single state) of 226 ± 30 keV.

(3) 20F: the lowest T = 2 state was observed at an excitation of 6513 ± 5 keV; the spin and parity were confirmed to be 0+. A second state, tentatively identified as T = 2 from the level spacing, was located at 8210 ± 6 keV.

(4) 28Al: the lowest T = 2 state was identified at an excitation of 5997 ± 6 keV; the spin and parity were confirmed to be 0+. A second state at an excitation energy of 7491 ± 11 keV is tentatively identified as T = 2, with a corresponding (tentative) spin and parity assignment Jπ = 2+.

The results of the present work and the other known masses of T = 2 states and nuclei for 8 ≤ A ≤ 28 are summarized, and massequation coefficients have been extracted for these multiplets. These coefficients were compared with those from T = 1 multiplets, and then used to predict the mass and stability of each of the unobserved members of the T = 2 multiplets.

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The processes of synthesis and destruction of organic matter play an important role in the ”self-cleaning” of reservoirs. The basic problem of this investigation consists of the role of phytoplankton in enriched waters of the Klyaz'minsk water reservoir through the solution of oxygen and its part in the ”self-cleaning” of the water reservoir. Observations on the interesting process of photosynthesis and the breakdown of organic matter was conducted by us on the eastern stretch of water in the Klyaz'minsk Reservoir during the growing periods of 1945 to 1948, by the widely applied bottle method (Vinberg 1934). This study reports mainly on the he vertical distribution of photosynthesis and respiration in plankton of the reservoir.

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El Congreso "Humanizar la Educación / Hezkuntza Gizatiartu", desarrollado en Bilbao los días 27, 28 y 29 de junio de 2014, es una propuesta dirigida a todos los agentes que constituyen la comunidad educativa. La finalidad de este evento consiste en generar un espacio de dimensión humana para compartir experiencias de trabajo, propiciar vivencias técnicas orientadas al autoconocimiento, y estimular actitudes responsables y creativas que posibiliten humanizar la educación. Está dirigido a todas las personas implicadas y comprometidas con la educación, independientemente del nivel, ámbito y rol en el que ésta se desarrolle; nos referimos a personas receptivas y que confíen en que el cambio comienza en uno mismo. Este marco ofrece una oportunidad para reconocer y hacer visibles realidades educativas ya existentes en esta línea y para nutrir aquellas que pudieran gestarse. Este evento, organizado por la UPV/EHU, se oferta en el marco de los Cursos de Verano / Cursos Europeos de la Fundación Cursos de Verano de la UPV/EHU y cuenta con la colaboración especial de la Fundación Claudio Naranjo. Para su desarrollo, además, cuenta con la ayuda de numerosas entidades, asociaciones, centros y profesionales que tienen la convicción de que educar es mucho más que compartir conocimiento; es una responsabilidad conjunta de todos los que configuramos el mapa educativo.

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惯性约束聚变(ICF)研究的长远目标,是实现可控核聚变,为人类提供理想的能源。神光Ⅱ高功率激光装置是由中国科学院、中国工程物理研究院、国家高技术863计划支持的大科学工程项目。该装置是目前我国规模最大、国际上为数不多的高性能高功率固体激光装置,是我国中近期惯性约束聚变重要实验平台。

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Estudos demonstram a associação de alterações da apolipoproteína E (ApoE) e do receptor do LDL (RLDL) com a ocorrência de doenças cardiovasculares e dislipidemia. O objetivo principal deste trabalho foi investigar a associação entre genótipos diferenciais da ApoE e do RLDL com a persistência de alterações de variáveis lipídicas em indivíduos jovens acompanhados há 28 anos no Estudo do Rio de Janeiro (ERJ). Através de um estudo longitudinal, tipo coorte, investigou-se 56 indivíduos (35M) em três avaliações. Em A1 (13.301.53 anos), A2 (22.091.91 anos) e A3 (31.231.99). Nas três ocasiões foi realizada avaliação clínica. Em A2 e A3 foram dosados colesterol total, HDL, LDL e triglicerídeos. Em A3 acrescentou-se o estudo dos polimorfismos genéticos da ApoE e do RLDL. Os fragmentos de interesse neste estudo foram amplificados por PCR (polymerase chain reaction) e os genótipos foram identificados através de reações de restrição. As frequências genotípicas de ApoE foram ε3/ε3 (62,5%), ε3/ε4 (25%), ε2/ε3 (5,4%) ,ε2/ε4 (5,4%) e ε4/ε4 (1,8%) e para os genótipos de RLDL foram AA (85,7%), AT (12,5%) e TT (1,8%). O genótipo ε2/ε2 não foi observado. A análise da distribuição dos genótipos de ApoE segundo a permanência de dislipidemia mostrou que todos os indivíduos com genótipo de ApoE dos tipos ε2/ε4 e ε4/ε4 mantiveram pelo menos um lípide alterado em A2 e A3 entretanto, todos os indivíduos com genótipo de ApoE do tipo ε2/ε3 não apresentaram lípides alterados em A2 e A3. Para o genótipo do RLDL não houve diferença significativa. Quando analisadas isoladamente, não foi identificado nenhum resultado significativo em A2 e/ou A3 associado a estes genótipos. O polimorfismo do gene da ApoE esteve associado à permanência de dislipidemia em indivíduos jovens acompanhados em estudo de seguimento longitudinal

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This publication gives the results of the bottom trawlings made during the cruises Togo 3 and logo 4 by the oceanographic research vessel "Andre NIZERY" on the continental shelf of Togo during the estimation program of halieutic resources. The report includes: 1 - The report of the cruises Togo 3 and Togo 4 2 - Some information on the presentation of the results 3 - The trawl recording cards for the 2 cruises 4 - The length frequency distributions of the measured samples.