A large amount of accumulated precipitation was recorded over the Eastern Periphery of the Tibetan Plateau(EPTP)in August 2020.Using hourly rain gauge records and the ERA5 reanalysis dataset,we analyzed the unique cha...A large amount of accumulated precipitation was recorded over the Eastern Periphery of the Tibetan Plateau(EPTP)in August 2020.Using hourly rain gauge records and the ERA5 reanalysis dataset,we analyzed the unique characteristics of rainfall in August and the accompanying circulation conditions and conducted a comparison with previous data.This record-breaking amount of accumulated rainfall was centered on the northern slope of the EPTP.This location was in contrast with the historical records of the concentration of rainfall over the middle and southern slopes.The hourly rainfall in August 2020 was both more frequent and more intense than the climatological mean rainfall.An amplification effect of the topography was observed,with the precipitation over the EPTP showing a more significant change with terrain height in August 2020.A circulation analysis showed that cold(warm)anomalies existed over the north(south)of approximately 35°N compared with those in the years when the southern EPTP received more rain.The western Pacific subtropical high was more intense and extended to the west,and the low-level cold air from the north was more active.The enhanced low-level southerly winds on the periphery of the subtropical high injected warm,moist air further north than the climatological mean.These winds became easterly near the northern EPTP and were forced to ascend by the steep terrain.展开更多
Objective: The medicinal mushroom Sanghuangporus vaninii produces pharmaceutically valuable hispidin polyphenols in natural habitats. However, due to the slow growth in nature, S. vaninii grown in the field(sclerotia)...Objective: The medicinal mushroom Sanghuangporus vaninii produces pharmaceutically valuable hispidin polyphenols in natural habitats. However, due to the slow growth in nature, S. vaninii grown in the field(sclerotia) is not reliable for pharmaceutical purposes. Although higher biomass of fungal mycelia can be obtained in submerged cultures, the accumulation of hispidin polyphenols is rare.Methods: In this study, the polyunsaturated fatty acids(PUFAs), linoleic acid(LA), linolenic acid(ALA),and methyl jasmonate(Me Ja) were employed as the stimulant agents to coordinate the accumulation of biomass and hispidin polyphenols in its submerged cultures.Results: The addition of LA and ALA promoted the mycelial accumulation, while the addition of Me Ja inhibited the growth of S. vaninii concomitant with reduced total polyphenols. UPLC-Triple-TOF-MS analysis revealed an increased production of hispidin, phellinstatin, pinnilidine, and its derivatives upon the addition of LA and ALA, and hypholomine B and its isomer, 3,14’-bihispidinyl, and phelligridin E upon the addition of Me Ja on day 13. Intriguingly, total polyphenols from the Me Ja-supplementing cultures harbored a high capacity in scavenging free radicals. Chemical structural analysis showed that hispidin polyphenols had higher antioxidant activity due to more hispidin moieties induced by Me Ja.Conclusion: The supplement of PUFAs affects the synthesis and composition of hispidin polyphenols in S.vaninii. Our results provide a possibility to coordinate the production of hispidin polyphenols via submerged cultures of S. vaninii.展开更多
Strong rainfall events originated from the northeast(NE)and southwest(SW)directions of the plain area of Beijing City(BJP)over 8 recent warm seasons(May–September of 2009–2016)were analyzed by using hourly merged ra...Strong rainfall events originated from the northeast(NE)and southwest(SW)directions of the plain area of Beijing City(BJP)over 8 recent warm seasons(May–September of 2009–2016)were analyzed by using hourly merged rainfall,satellite brightness temperature,and the fifth-generation ECMWF reanalysis(ERA5)data.Such heavy regional rainfall events(RREs)with different origins present quite different features in both the precipitation itself and its corresponding circulations.The heavy RREs originated from the SW occur more frequently in the flood season of North China(July and August),and the peak time of rainfall occurrences is in the early morning.They are linked with stronger large-scale circulation forcing,compared with the NE-originated events.Meanwhile,the ratio of heavy rainfall to the total rainfall in SW-originated events,the mean spatial coverage of rainfall,and associated convective index,are also larger,for the SW events.The heavy RREs from the NE occur more frequently in June and July(before the traditional flood season),with a more apparent afternoon peak.They exhibit stronger convective features,with higher maximum convective index values,but the large-scale forcing is weaker at the hour of onset.These features of the RREs from different directions of Beijing City and associated precursor circulation signals help better forecast RREs over the BJP.展开更多
基金This work was jointly supported by the National Key R&D Program of China(Grant No.2018YFC1507603)the National Natural Science Foundation of China(Grant No.41875112).
文摘A large amount of accumulated precipitation was recorded over the Eastern Periphery of the Tibetan Plateau(EPTP)in August 2020.Using hourly rain gauge records and the ERA5 reanalysis dataset,we analyzed the unique characteristics of rainfall in August and the accompanying circulation conditions and conducted a comparison with previous data.This record-breaking amount of accumulated rainfall was centered on the northern slope of the EPTP.This location was in contrast with the historical records of the concentration of rainfall over the middle and southern slopes.The hourly rainfall in August 2020 was both more frequent and more intense than the climatological mean rainfall.An amplification effect of the topography was observed,with the precipitation over the EPTP showing a more significant change with terrain height in August 2020.A circulation analysis showed that cold(warm)anomalies existed over the north(south)of approximately 35°N compared with those in the years when the southern EPTP received more rain.The western Pacific subtropical high was more intense and extended to the west,and the low-level cold air from the north was more active.The enhanced low-level southerly winds on the periphery of the subtropical high injected warm,moist air further north than the climatological mean.These winds became easterly near the northern EPTP and were forced to ascend by the steep terrain.
基金supported by the National Key Research and Development Project of China[Grant Nos.2018YFC1507104 and 2018YFC1507603]the National Natural Science Foundation of China[Grants Nos.91937301,41875074,and 41675060]the National Key Scientific and Technological Infrastructure Project“Earth Lab”。
基金supported by National Natural Science Foundation of China (No. 31170063 and 31470173) for Weifa Zheng。
文摘Objective: The medicinal mushroom Sanghuangporus vaninii produces pharmaceutically valuable hispidin polyphenols in natural habitats. However, due to the slow growth in nature, S. vaninii grown in the field(sclerotia) is not reliable for pharmaceutical purposes. Although higher biomass of fungal mycelia can be obtained in submerged cultures, the accumulation of hispidin polyphenols is rare.Methods: In this study, the polyunsaturated fatty acids(PUFAs), linoleic acid(LA), linolenic acid(ALA),and methyl jasmonate(Me Ja) were employed as the stimulant agents to coordinate the accumulation of biomass and hispidin polyphenols in its submerged cultures.Results: The addition of LA and ALA promoted the mycelial accumulation, while the addition of Me Ja inhibited the growth of S. vaninii concomitant with reduced total polyphenols. UPLC-Triple-TOF-MS analysis revealed an increased production of hispidin, phellinstatin, pinnilidine, and its derivatives upon the addition of LA and ALA, and hypholomine B and its isomer, 3,14’-bihispidinyl, and phelligridin E upon the addition of Me Ja on day 13. Intriguingly, total polyphenols from the Me Ja-supplementing cultures harbored a high capacity in scavenging free radicals. Chemical structural analysis showed that hispidin polyphenols had higher antioxidant activity due to more hispidin moieties induced by Me Ja.Conclusion: The supplement of PUFAs affects the synthesis and composition of hispidin polyphenols in S.vaninii. Our results provide a possibility to coordinate the production of hispidin polyphenols via submerged cultures of S. vaninii.
基金Supported by the National Key Research and Development Program of China(2018YFE0196000 and 2018YFC1507603)National Natural Science Foundation of China(41675075 and 41875112)。
文摘Strong rainfall events originated from the northeast(NE)and southwest(SW)directions of the plain area of Beijing City(BJP)over 8 recent warm seasons(May–September of 2009–2016)were analyzed by using hourly merged rainfall,satellite brightness temperature,and the fifth-generation ECMWF reanalysis(ERA5)data.Such heavy regional rainfall events(RREs)with different origins present quite different features in both the precipitation itself and its corresponding circulations.The heavy RREs originated from the SW occur more frequently in the flood season of North China(July and August),and the peak time of rainfall occurrences is in the early morning.They are linked with stronger large-scale circulation forcing,compared with the NE-originated events.Meanwhile,the ratio of heavy rainfall to the total rainfall in SW-originated events,the mean spatial coverage of rainfall,and associated convective index,are also larger,for the SW events.The heavy RREs from the NE occur more frequently in June and July(before the traditional flood season),with a more apparent afternoon peak.They exhibit stronger convective features,with higher maximum convective index values,but the large-scale forcing is weaker at the hour of onset.These features of the RREs from different directions of Beijing City and associated precursor circulation signals help better forecast RREs over the BJP.
