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61.
A new virus named Nootka lupine vein-clearing virus (NLVCV) was isolated from Lupinus nootkatensis plants that were confined to a relatively small area in the Talkeetna mountains of south-central Alaska. Annual surveys (2000–03) consistently found leaf symptoms of pronounced vein clearing and mosaic on 3- to 4-week-old plants in late June. Spherical particles ≈30 nm in diameter were isolated from these leaves. Virions contained a single-stranded RNA of ≈4·0–4·2 kb and one species of capsid protein estimated to be ≈40 kDa. The double-stranded RNA profile from naturally infected leaves consisted of three major bands ≈4·2, 1·9 and 1·5 kbp. Protein extractions from either sap or virions of diseased plants reacted to polyclonal antiserum made against the virions in Western blot assays. A predicted PCR product ≈500 bp was synthesized from virion RNA using primers specific to the carmovirus RNA-dependent RNA polymerase (RDRP) gene. The nucleotide sequence of the amplified DNA did not match any known virus, but contained short regions of identity to several carmoviruses. Only species belonging to the Fabaceae were susceptible to NLVCV by mechanical inoculation. Based on dsRNA profile, size of virion RNA genome and capsid protein, and similarity of the RDRP gene to that of other carmoviruses, it is suggested that NLVCV is a member of the family Tombusviridae , and tentatively of the genus Carmovirus . As the host range, RDRP gene and dsRNA profile of NLVCV are different from those of known viruses, this is a newly described plant virus.  相似文献   
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In recent years, natural deep eutectic solvents (NADES) have been widely investigated for the extraction of food and medicinal plants as well as seaweeds. However, the ability of NADES for trace elements co-extraction from natural sources is not well investigated. The aim of this study was to investigate the ability of common NADES for trace elements co-extraction from Fucus vesiculosus. All of the tested NADES did not recover As and Co (concentration <LOQ). Moreover, all of the tested NADES provided a low recovery (<9%) of Ba, Ca, Fe, Mg, Mn, Sr, and Zn. The method of extraction had not shown a statistically significant effect on the co-extraction of all elements (excluding Ba and Ca). In contrast, the water content in NADES was significantly affected on the recovery of Ba, Ca, Mg, Mn, Sr, and Zn. The recovery of Al and Cr was relatively high and considerably varied (from 1.5 to 59.9%). NADES comprising lactic acid:glucose:H2O (5:3:1) provided the lowest contents of all elements, and the highest extracted amounts were obtained employing water contents of 60–80%. The calculated daily intake of all the elements contained in NADES extracts were less than the daily dose risk estimators. The hazard quotients, hazard indexes, and carcinogenic risk calculated for all trace elements and their combination were considerably less than 1. This evidences no health risk, and carcinogenic risk after topical application of all studied NADES. For the first time, the results of the current study demonstrated that NADES extracts of F. vesiculosus contain a lower amount of trace metals and are safer than the extracts obtained with water and 70% acetone. This indicates a significant advantage for NADES compared with the other solvents.  相似文献   
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Sampling of the benthic fauna showed that dredging operations produced relatively short-term effects on invertebrate population levels. The behaviour of the animals was immediately affected, the differences between species were noted and the implications of dredging at different times of year are discussed.  相似文献   
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The lignin content of 50 samples of five grasses of known in vivo digestibility were determined by the methods of Armitage, van Soest and two modifications of the van Soest technique. The error in predicting DM digestibility varied from ±3.1 for tbe Armitage metbod to ±5.0 for the van Soest method. This error compares nnfavourably witb ±2.1 previonsly obtained on tbe same samples with the in vitro technique of Tilley and Terry.  相似文献   
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Ohne Zusammenfassung  相似文献   
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