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Application of organic wastes to cultivated lands can replace mineral fertilizers but may also alter soil physical properties and enhance pollution potential. The objective of this study was to investigate the effects of biosolids [composted manure (MC) and activated sludge (AS)] and specific biosolid component [orthophosphate (OP), phytic acid (PA) and humic acid (HA)] application on soils differing in texture [loamy‐sand (Ramat‐HaKovesh, RH), loam (Gilat, GL) and clay (Bet‐Dagan, BD)], infiltration rate, runoff volume and soil sediment loss. The soils were packed in erosion boxes (400 × 200 × 40 mm) and subjected to six consecutive simulated rainstorms, each of 186 mm deionized water. The results showed that runoff volume and sediment loss from untreated soils increased with increasing clay contents. In treated soils, the response to AS application differed from the response to other amendments; in the BD clay and GL loam, it was the only amendment that caused a decrease in sediment removed by runoff. In the RH loamy‐sand, all amendments reduced the final infiltration rate, but only AS and HA increased the measured runoff. It is proposed that the difference in the response of the soils to the amendments is associated with the soil's ability to attenuate changes in the negative charge on the clay edges following the increase in the specific adsorption of charged anions, thus controlling clay swelling and maintaining aggregate integrity. The effects of amending soils with a source of organic matter in order to control runoff and soil erosion are not straight forward and depend on soil and amendment properties. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Journal of Plant Diseases and Protection - Pythium aphanidermatum is the most wide-spread root pathogen in greenhouse cucumber. Although environmental condi-tions are known to affect the disease...  相似文献   
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A dichloromethane extract of the soft coral Rhytisma fulvum fulvum collected in Madagascar afforded a novel compound possessing an unprecedented pentacyclic skeleton, bisdioxycalamenene (1), as well as seven known sesquiterpenes. The structures of the compounds were elucidated using 1D and 2D NMR techniques, as well as high-resolution mass spectrometry. The absolute configuration of 1 was determined using X-ray diffraction analysis and anomalous dispersion effects. The structure elucidation and a possible biogenesis of the compound are discussed.  相似文献   
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A zooxanthellae-free soft coral from the Red Sea feeds almost exclusively on phytoplankton, a mode of nutrition so far unknown for corals. Herbivory was also found in three other azooxanthellate soft corals. In tropical oligotrophic waters, phytoplankton biomass density may be an order of magnitude higher than that of zooplankton. Use of this resource allows these azooxanthellate cnidarians to be highly productive in flow-exposed oligotrophic reef waters.  相似文献   
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The octcoral Sarcophyton glaucum has a wide Indo‐Pacific distribution and is known for its diverse content of natural products. The aim of the current study was to establish a protocol for rearing miniature cuttings of S. glaucum in a closed seawater system. In order to determine the optimal conditions for rearing, the survival, average dry weight, percentage of organic weight and development of the cuttings were monitored under different temperature, light, salinity and feeding regimes. At 26 °C, the highest dry weight was obtained, and at 20 °C, the highest percentage of organic weight. The dry weight of the cuttings increased with the light intensity, while under 35–130 μE m?2 s?1, survival was high. Salinity did not affect any of the colonies' features. Feeding intervals of 7 and 30 days yielded a better result than of 2 days. A comparison of the colonies derived from the closed system with the colonies reared in a flow‐through system, those reared in the sea and with field‐collected colonies revealed the importance of environmental conditions in determining the features of the colonies. The study emphasizes the advantages of a closed seawater system in controlling the conditions needed for rearing cuttings of S. glaucum for targeted farming.  相似文献   
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Biomedical engineering combines engineering and materials methods to restore, maintain, improve, or replace different types of biological tissues. In tissue engineering, following major injury, a scaffold is designed to support the local growth of cells, enabling the development of new viable tissue. To provide the conditions for the mechanical and structural properties needed for the restored tissue and its appropriate functioning, the scaffold requires specific biochemical properties in order to ensure a correct healing process. The scaffold creates a support system and requires a suitable material that will transduce the appropriate signals for the regenerative process to take place. A scaffold composed of material that mimics natural tissue, rather than a synthetic material, will achieve better results. Here, we provide an overview of natural components of marine-derived origin, the collagen fibers characterization schematic is summarized in the graphical abstract. The use of collagen fibers for biomedical applications and their performances in cell support are demonstrated in an in vitro system and in tissue regeneration in vivo.  相似文献   
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