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341.
Annual Zooplankton Succession in Coastal NW Mediterranean Waters: The Importance of the Smaller Size Fractions 总被引:12,自引:0,他引:12
Calbet Albert; Garrido Susana; Saiz Enric; Alcaraz Miquel; Duarte Carlos M. 《Journal of plankton research》2001,23(3):319-331
Zooplankton abundance, biomass (biovolume) and taxonomic compositionwere studied within an annual cycle (August 1995October1996) in the Bay of Blanes (northwest Mediterranean). Weeklyzooplankton sampling included oblique tows made with a 200 µmJudayBogorov net, and vertical tows made with a 53 µmnet, to adequately sample both mesoplankton and the smallerzooplankton fractions. Total zooplankton abundance showed highvariability, lacking any clear seasonal pattern. However, thedifferent species within the zooplankton community displayeda clear succession throughout the year. In general, cyclopoidcopepods (Oithona spp.) and cladocerans (Peniliaavirostris)dominated the summer and autumn communities, whereas in winterand spring, calanoid copepods (Clausocalanus spp., Paracalanussp. and Centropages typicus) were predominant. The zooplanktonannual cycle in the Bay of Blanes does not resemble those ofother Mediterraneanlittoral areas, probably due to the inherentparticularity and variability associated with open coastal environments.On average, the abundance of organisms estimated with a traditional200 µm JudayBogorov net was 8.1 times lower thanthe values obtained with a 53 µm net. Even if only organisms>200 µm collected in the 53 µm tows were considered,the total abundance within the 53 µm net was still 4.4times higher than the estimates from the JudayBogorovnet. These results suggest the need for accurate samplings ofthe entire zooplankton assemblage when characterizing the structureand dynamics of zooplanktonic communities. 相似文献
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Enric Duaso Santiago Tomás Mónica Rodríguez-Carballeira Leonor Cuadra Mireia Llonch Domingo Ruiz 《Revista espa?ola de geriatría y gerontología》2009
Elderly people use often and in an appropriate way the Emergency Department (ED). However, we don’t dispose of evidences that demonstrate utility of a specific model of geriatric assessment (GA) applied in ED. Nowadays; GA in ED should be used being adapted to the environment and with some clear objectives that allow to carry out a multidimensional diagnosis and to establish therapeutic priorities. GA contributes benefits in the continuity of care on the part of the Primary Attention when elderly people are discharged from an ED. 相似文献
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Duane Andrea Kelly Luke Giljohann Kate Batllori Enric McCarthy Michael Brotons Lluís 《Ecosystems》2019,22(6):1338-1351
Ecosystems - Understanding the interplay between climate, fuel and fire is necessary for developing strategies that minimize the negative impacts of fire on people and ecosystems. Here, we aim to... 相似文献
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Foregut morphology and ontogeny of the spider crab Maja brachydactyla (Brachyura,Majoidea, Majidae)
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Diego Castejón Guiomar Rotllant Enric Ribes Mercè Durfort Guillermo Guerao 《Journal of morphology》2015,276(9):1109-1122
We describe the morphology of the foregut of the spider crab Maja brachydactyla Balss, 1922, from first larval stage to adult, with detailed stage‐specific documentation using light and scanning electron microscopy. A total of 40 ossicles have been identified in the foregut of adults of M. brachydactyla using Alizarin‐Red staining. The morphological pattern of the ossicles and gastric mill is very similar to other Majoidea species with only a few variations. The foregut of the zoeae stages appeared as a small and simple cavity, with a cardio‐pyloric valve that separates the stomach into cardiac and pyloric regions. The pyloric filter is present from the first zoea, in contrast to the brachyuran species which have an extended larval development. Calcified structures have been identified in the cardio‐pyloric valve and pyloric region of the zoeal stages. The most significant changes in foregut morphology take place after the metamorphosis from ZII to megalopa, including the occurrence of the gastric mill. In the megalopa stage, the foregut ossicles are recognizable by their organization and general morphology, but are different from the adult phase in shape and number. Moreover, the gastric teeth show important differences: the cusps of the lateral teeth are sharp (no molariform); the dorsal tooth have a small, dentate cusp (not a well‐developed quadrangular cusp); and the accessory teeth are composed of one sharp peak (instead of four sharp peaks). The gastric mill ontogeny from megalopa to adult reveals intermediate morphologies during the earlier juvenile stages. The relationship between gastric mill structures with food preferences and their contribution to the brachyuran phylogeny are briefly discussed. J. Morphol. 276:1109–1122, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
348.
Karyotype Rearrangements in a Wine Yeast Strain by rad52-Dependent and rad52-Independent Mechanisms 总被引:1,自引:0,他引:1
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Yeast strains isolated from the wild may undergo karyotype changes during vegetative growth, a characteristic that compromises their utility in genetic improvement projects for industrial purposes. Karyotype instability is a dominant trait, segregating among meiotic derivatives as if it depended upon only a few genetic elements. We show that disrupting the RAD52 gene in a hypervariable strain partially stabilizes its karyotype. Specifically, RAD52 disruption eliminated recombination at telomeric and subtelomeric sequences, had no influence on ribosomal DNA rearrangement rates, and reduced to 30% the rate of changes in chromosomal size. Thus, there are at least three mechanisms related to karyotype instability in wild yeast strains, two of them not requiring RAD52-mediated homologous recombination. When utilized for a standard sparkling-wine second fermentation, Δrad52 strains retained the enological properties of the parental strain, specifically its vigorous fermentation capability. These data increase our understanding of the mechanisms of karyotype instability in yeast strains isolated from the wild and illustrate the feasibility and limitations of genetic remediation to increase the suitability of natural strains for industrial processes. 相似文献
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B. Zelazny 《Journal of invertebrate pathology》1973,22(1):122-126
Rhabdionvirus oryctes multiplies in adults of Oryctes rhinoceros. Adults and larvae of O. rhinoceros showed no significant difference in their susceptibility to the virus when it was inoculated into the hemocoel. Adults, collected from the natural population in Western Samoa, were found to be frequently infected with Rhabdionvirus. In the laboratory the infected adults had a shorter life-span and laid fewer eggs than the noninfected ones. Infected adults excreted virus material into the surrounding medium. This suggests a possible means of transmission of the virus in the field. 相似文献