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Gregory A. Ellis Thomas P. Wyche Charles G. Fry Doug R. Braun Tim S. Bugni 《Marine drugs》2014,12(2):1013-1022
Two novel trialkyl-substituted aromatic acids, solwaric acids A and B, were isolated from a marine Solwaraspora sp. cultivated from the ascidian Trididemnum orbiculatum. Solwaric acids A and B were isotopically labeled with U-13C glucose, and analysis of a 13C–13C COSY allowed for unambiguous determination of the location of the phenyl methyl group. The two novel compounds demonstrated antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA). 相似文献
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Ecological weed management (EWM) is a scientifically established management approach that uses ecological patterns to reduce weed seedbanks. Such an approach can save organic farmers time and labor costs and reduce the need for repeated cultivation practices that may pose risks to soil and water quality. However, adoption of effective EWM in the organic farm community is perceived to be poor. In addition, communication and collaboration between the scientific community, extension services, and the organic farming community in the US is historically weak. In order to uncover the most persistent obstacles to promoting effective weed management in organic agroecosystems, we use the mental models approach to generate an expert model based on interviews with experts (e.g., weed scientists, weed ecologists, and extension personnel) and theories from the behavioral sciences. The expert model provides two main insights: (1) EWM is a complex strategy that may cause farmers to use heuristics in management decisions and (2) the long-term benefits of EWM, rather than the risks, need to be emphasized in communication with and outreach to organic farmers. The basis for new research topics and outreach material that incorporates these insights from the expert model are discussed. We briefly explain how the expert model is an incomplete picture of on-farm practices, but provides the basis for the second step of our mental models research, the farmer interviews and farmer decision model development. 相似文献
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Concern about poor natural regeneration of blue oak in California has prompted efforts to artificially regenerate this species. Two studies examined the best time to collect acorns and the effect various pre-storage treatments, including soaking and drying, have on germination. Results indicated that acorns can be successfully collected over a fairly wide interval, extending from late August until late October. Acorns from all harvest dates had high germination, as long as they were not allowed to dry out before storage. However, the earlier the acorns were collected, the earlier they tended to germinate. Soaking acorns for a day prior to storage had little effect. Drying acorns, however, reduced both the rate and amount of germination. A 10% reduction in moisture content resulted in almost 40% less total germination, and all acorns that lost 25% or more of their mositure failed to germinate during the 10-week test interval. To ensure good seed quality, blue oak acorns should be collected directly from tree branches and placed immediately in cold storage. 相似文献
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