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Coral populations have precipitously declined on Caribbean reefs while algal abundance has increased, leading to enhanced competitive damage to corals, which likely is mediated by the potent allelochemicals produced by both macroalgae and benthic cyanobacteria. Allelochemicals may affect the composition and abundance of coral-associated microorganisms that control host responses and adaptations to environmental change, including susceptibility to bacterial diseases. Here, we demonstrate that extracts of six Caribbean macroalgae and two benthic cyanobacteria have both inhibitory and stimulatory effects on bacterial taxa cultured from the surfaces of Caribbean corals, macroalgae, and corals exposed to macroalgal extracts. The growth of 54 bacterial isolates was monitored in the presence of l...

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-Estudio sobre la fijacion de nitrogeno, fotosintesis y reconolizacion ... - Fotosintesis y relaciones hidricas en liquenes nanofruticulosos antarticos. ...

British Library Electronic Table of Contents (United Kingdom)

Samples of two seawater farmed fish (crimson snapper (Lutjanus erythopterus) and snubnose pompano (Trachinotus blochii)), water, air, sediment, fish feed, macroalgae and phytoplankton were collected from two estuarine bays (Daya Bay and Hailing Bay) in South China. The concentrations of persistent halogenated compounds (PHCs) including polybrominated diphenyl ethers (PBDEs), organochlorine pesticides and polychlorinated biphenyls (PCBs) varied widely with the different sample matrices under investigation. The compositional patterns in fish, fish feed, macroalgae and phytoplankton, as well as the good correlations between the abundances of p,pprime-DDT and BDE-209 and their metabolites (i.e., p,pprime-DDD and p,pprime-DDE for p,pprime-DDT and BDE-47 for BDE-209) in fish indicated the occurr...

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British Library Electronic Table of Contents (United Kingdom)

We studied the mechanism of Ascophyllum nodosum (a brown macroalga) induced resistance in Arabidopsis thaliana against Pseudomonas syringae pv. tomato DC3000. Root treatment of A. thaliana Col-0 plants with extracts of A. nodosum [aqueous (ANE), chloroform (C-ANE) and ethylacetate fractions, (E-ANE)] reduced the development of disease symptoms on the leaves. These extracts also induced resistance in salicylic acid deficient NahG and ics1 plants. However, the extracts did not elicit an effect on jar1 (jasmonic acid resistance 1) mutant. A. nodosum extract induced resistance to Pst DC3000 correlated with increased expression of jasmonic acid related gene transcripts PDF1.2 while PR1 and ICS1 expression were less affected. Additionally, pretreatment of Arabidopsis plants with ANE, protected t...

British Library Electronic Table of Contents (United Kingdom)

Through their grazing activities limpets have an important role in controlling macroalgal abundance and as a result the structure and dynamics of rocky shore assemblages. Using two congeneric limpet species, with different biogeographic distributions, and whose ranges are expected to alter with climatic warming, we separated the magnitude of their grazing activity over time and the subsequent consequence for macroalgal growth.The northern/boreal limpet, Patella vulgata (L.), consistently grazed more than the southern/lusitanian limpet, P. depressa (Pennant), particularly during spring and summer when P. depressa was reproductively active. Individuals of Fucus vesiculosus (L.) that settled during this time were able to grow to a size where they escaped the grazing activities of P. depressa,...

Energy Technology Data Exchange (ETDEWEB)

This document contains the technical proceedings of the 19 national seminar on the rational use of energy and exposition of equipment and services, organized by the Asociacion de Tecnicos y Pofesionistas en Aplicacion Energetica (ATPAE) (Association of Technicians and Professionals on Energy Application) conducted in Mexico City on September 21-25, 1998. This seminar encompassed subjects such as: energy saving in the energy sector, energy efficiency in industrial processes and practical developments, practical cases of energy saving in industry, energy saving in buildings, transportation, non-renewable energy utilization and environmental impact and eco-energies. [Espanol] Este documento contiene la memoria tecnica del 19 seminario nacional sobre el uso racional de la energia y exposicion de equipos y servicios, organizado por la Asociacion de Tecnicos y Profesionistas en Aplicacion Energetica (ATPAE), en Mexico, D.F, los dias 21-25 de septiembre de 1998. Este ...

British Library Electronic Table of Contents (United Kingdom)

Introduccion y objetivos Aunque los bloqueos de rama (BR) se consideran hallazgos frecuentes, la informacion sobre su prevalencia real en la poblacion general es escasa, y es inexistente en los pacientes en dialisis. El objetivo es establecer la prevalencia del BR completo en la poblacion que inicia dialisis y los factores relacionados con su aparicion. Como analisis adicional, se explora su asociacion con la mortalidad y con la aparicion de un evento cardiovascular. Metodos Se incluyo a los pacientes que iniciaron dialisis en nuestro centro entre el 1 de noviembre de 2003 y el 31 de diciembre de 2006. Todos fueron sometidos a valoracion cardiologica al inicio de dialisis. Determinamos el BR y su relacion con factores clinicos y parametros ecocardiograficos y bioquimicos. Los pacientes fue...

Energy Technology Data Exchange (ETDEWEB)

In order to evaluate the effects of radioactivity on active vegetal substances, samples of Fennel (Foeniculum vulgare Miller., fructus), Guarana (Paulinia cupana, Kunth, semen), Gingko (gingko biloba, L., folium), and Kawa-Kawa (Piper methysticum G. Forst, rhizoma), were treated with scaling doses (0 to 25 KGy) of gamma radiation (Co{sup 60}). The 'blind test' methodology was used. The active substances from each sample were analysed by qualitative and quantitative methods after radiation. There were no significant differences seen between the control sample (0 KGy) and the irradiated samples. Microbe contamination was significantly reduced, about 10000 CFU/g, with the initial 5 KGy dose. It was concluded that gamma radiation can be used as an alternative procedure to reduce microbiologic contamination in medicinal plants. Before this procedure can be extended to other medicinal plants, more specific analytical methods are recommended to verify possible structural ...

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Both solvent extraction and spectrophotometric techniques were used to show the alterations that gamma radiation causes in the behavior of tetracycline molecule as far as its extracting and complexing power are concerned. The effect of gamma radiation on the solid tetracycline molecule, benzyl alcohol and on the solution of both was examined in solvent extraction systems whose aqueous phases were made up by {sup 152} Eu-{sup 154}Eu radioactive tracer solutions and whose organic phases were constituted by tetracycline-benzyl alcohol solutions. Experiments were performed in order to determine whether or not the water used for the pre-saturation of benzyl alcohol would influence the radiolysis of tetracycline. Solvent extraction and spectrophotometry were the techniques used to obtain the necessary data. Absorption spectra of irradiated tetracycline benzyl alcohol solutions submitted to several gamma radiation doses were examined and the alterations shown by these spectra were examined. ...

Energy Technology Data Exchange (ETDEWEB)

The use of medicinal plants in the treatment of diseases has increased significantly in the last years, as has research concerning chemical characterization of these plants. In this study, inorganic constituents were determined in leaves and in extracts from three medicinal plant species of the Casearia genus (C. sylvestris, C. decandra and C. obliqua) collected in distinct regions of the Atlantic Forest, SP. The elemental compositions of the soils in which these plants were grown were also determined. Traditionally, these plants are used due to their antiinflammatory, antiacid, antiseptic and cicatrizing properties. The antiulcer and the antitumor activities of the Casearia genus and its capacity to neutralize snake and bee venoms, have also been scientifically confirmed. The analytical methodology used was neutron activation analysis. Long and short irradiation periods of the samples and the standards were carried out at IPEN's IEA-R1 nuclear research reactor. In the leaf K ...