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Pseurotins A1 (1) and A2 (2) were isolated from a culture broth of the fungal strain Aspergillus fumigatus WFZ-25 as stereoisomers of pseurotin A (3) in 2011. We also isolated 1 and 2 together with 3 from A. fumigatus OUPS-T106B-5 separated from the marine fish Mugil cephalus. In this study, we re-examined the stereochemistry of 1 and 2 using chemical transformation and the CD spectra, and found the relationship between the CD Cotton effect and the absolute configurations of 1 and 2, which led us to revise the stereostructure of pseurotin A2.  相似文献   
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Processes of globalisation in the conventional food provision system have had widespread negative impacts on small‐scale farmers. Yet, alternative food networks, which are characterised by more sustainable production/consumption practices and fairer trade relations, have increasingly been ‘going global’ and, in the process, have been integrating small‐scale farms in the South. One such high‐value export‐led commodity is certified organic shrimp. International third‐party certification schemes are becoming popular as a tool to verify the intangible attributes of such commodities. Using concepts of multifunctionality and agrarian change, this paper examines the implications of introducing an international environmental certification programme to a site where the ‘peasantry’ has been preserved and has limited integration in the global agro‐food system. Drawing on a case study that examines the first certified organic shrimp production project in Vietnam, this paper concludes that the current movement towards post‐productivism in the global North has potential to keep local farming practices in the global South by justifying the value of peasant‐like production methods through international certification. As a result, the development path of agrarian transition might be reshaped into a form not necessarily pursuing industrialisation. This leads to the new interpretation of pre‐ and post‐productivism beyond the North and South divide.  相似文献   
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Resistance in the leaf blades of rice plants against a virulent race of the rice blast fungus Magnaporthe oryzae was quantitatively examined using a modified spot inoculation method. Numbers of conidia produced in the lesions were affected by plant age and paralleled the frequency of resistance infection types, which is indicative of whole-plant-specific resistance (WPSR), in the inoculated leaf sheaths of the corresponding plants. Exogenous abscisic acid treatment, which suppresses WPSR, also increased the susceptibility of the leaf blades. These results indicate a correlation between the resistance of the leaf blades and the WPSR in the leaf sheaths.  相似文献   
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A loop-mediated isothermal amplification (LAMP) reaction with a primer set designed from the rDNA ITS sequence of P. aphanidermatum was developed. Results of a specificity test using 57 strains of Pythium spp. indicated that the LAMP assay gave no cross reactions in other 39 Pythium species, 11 strains of Phytophthora spp. and eight other soil borne pathogens. The detection limit was 10 fg of genomic DNA, which was ten times the sensitivity of the polymerase chain reaction. The LAMP assay was applied to hydroponic solution samples from tomato fields, and the results were compared to those of the conventional plating method. LAMP was observed to be effective for the specific detection of P. aphanidermatum. Furthermore, P. aphanidermatum was detected directly in tomato roots infected with P. aphanidermatum without DNA extraction. The LAMP method established in this study is a simple, sensitive and rapid tool for the detection of P. aphanidermatum.  相似文献   
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Bitterness-masking compounds were identified in a natural white mold cheese. The oily fraction of the cheese was extracted and further fractionated by using silica gel column chromatography. The four fractions obtained were characterized by thin-layer chromatography and nuclear magnetic resonance spectroscopy. The fatty acid-containing fraction was found to have the highest bitterness-masking activity against quinine hydrochloride. Bitterness-masking activity was quantitated using a method based on subjective equivalents. At 0.5 mM, the fatty acid mixture, which had a composition similar to that of cheese, suppressed the bitterness of 0.008% quinine hydrochloride to be equivalent to that of 0.0049-0.0060% and 0.5 mM oleic acid to that of 0.0032-0.0038% solution. The binding potential between oleic acid and the bitter compounds was estimated by isothermal titration calorimetry. These results suggest that oleic acid masked bitterness by forming a complex with the bitter compounds.  相似文献   
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Otitis externa in 27 toy poodles and 40 miniature dachshunds was treated using a video otoscope. A distinct concavity (external tympanic concavity) was observed at the junction between the ventral part of the external surface of the tympanum and the ear canal to which a considerable amount of hair and debris had adhered. All hair and debris adhering to the external tympanic concavity were removed, and systemic antibiotic and antifungal agents were administered, after which all of the dogs recovered. The pattern of hair growth observed in the external tympanic concavity could be characterized according to the breed of dog. All of the toy poodles presented with curly hairs, while the miniature dachshunds had upright or flat-lying hairs.  相似文献   
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