Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses o...Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses of wheat spikelets at various positions,leaves,and stems and the interactions between them at physiological levels remain unclear.In the present study,two-year treatments at terminal spikelet stage under two temperatures(2 C,-2 C) and durations(1,2,and 3 days) were imposed in an artificial climate chamber to compare the effects of LSC on grain number and yield in the wheat cultivars Yannong 19(YN19,cold-tolerant) and Xinmai 26(XM26,cold-sensitive).The night temperature regimes were designed to reproduce natural temperature variation.LSC delayed plant growth and inhibited spike and floret differentiation,leading to high yield losses in both cultivars.LSC reduced dry matter accumulation(DMA,g) in spikes,stems,and leaves,reducing the DMA ratios of the spike to leaf and spike to stem.Plant cell wall invertase(CWINV) activity increased in upper and basal spikelets in YN19,whereas CWINV increased in middle spikelets in XM26.Under LSC,soluble sugar and glucose were transported and distributed mainly in upper and basal spikelets for glume and rachis development,so that spike development was relatively complete in YN19,whereas the upper and basal spikelets were severely damaged and most of the glumes in middle spikelets were relatively completely developed in XM26,resulting in pollen abortion mainly in upper and basal spikelets.The development of glumes and rachides was influenced and grain number per spike was decreased after LSC,with kernels present mainly in middle spikelets.Overall,reduced total DMA and dry matter partitioning to spikes under LSC results in poor spikelet development,leading to high losses of grain yield.展开更多
The NCEP data were applied to analyze causes of 'late spring coldness' occurring twice in Dalian in late April and mid May of 2008.The results showed that the 500 hPa Baikal ridge of high pressure maintained o...The NCEP data were applied to analyze causes of 'late spring coldness' occurring twice in Dalian in late April and mid May of 2008.The results showed that the 500 hPa Baikal ridge of high pressure maintained or strengthened in a stable manner.The delivery of accumulated cold air toward southeast was along the northwest airstream before the ridge.Therefore,the ridge of high pressure over Lake Baikal provided access for the cold air southward so that the cold air could continue to decline,resulting in the appearance of low temperature in late April and formation of 'late spring coldness'.The Northeast cold vortex(NECV) occurred frequently in mid May.There was a high possibility for low temperature and pluvial damages over Dalian.Thus the phenomenon of 'late spring coldness' appeared again.展开更多
This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving processes.During an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies...This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving processes.During an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies and an anomalous anticyclone that continuously transport northern cold air to North China,causing significant,persistent,lower-than-normal daily temperatures.In fact,these positive SLP and anticyclonic wind anomalies begin to appear over northwestern Europe about 10 days prior to the ESCS.The anticyclonic wind anomalies keep moving southeastward and expand to the west of Lake Baikal until two days before the ESCS.Then,the center of the anomalous low-level anticyclone moves over Lake Baikal,inducing northerly wind anomalies that transport cold air into North China.In the following days,as the positive SLP anomalies weaken,the anomalous anticyclone and related northerly winds appear to wane,and the ESCS gradually comes to an end.The results may prove meaningful for the prediction and early warning of ESCSs.展开更多
The microbial diversity in Wuli Area, Qinghai-Tibetan Plateau was investigated using 16S rRNA gene phylogenetic analyses. A total of 117 bacterial and 66 archaeal 16S rRNA gene clones were obtained from the Wuli cold ...The microbial diversity in Wuli Area, Qinghai-Tibetan Plateau was investigated using 16S rRNA gene phylogenetic analyses. A total of 117 bacterial and 66 archaeal 16S rRNA gene clones were obtained from the Wuli cold springs, The bacterial clones could be classified into Proteobacteria, Acid- obacteria, Deinococci, Sphingobacteria, Flavobacteria, Nitrospirae, Actinobacteria, Gemmatimona- detes, and unclassified-bacteria; and the archaeal clones could be classified into Crenarchaeota and Thaumarchaeota. Among the major groups, Proteobacteria and Crenarchaeota were dominant in the bacterial and archaeal 16S rRNA gene clone libraries, respectively. The clone sequences obtained in Wuli cold springs were closely related to those from cold habitats, such as snow/ice/soils on high mountains or at high latitude. Especially, the microbial community composition of Wuli Area was more similar to that in Tibetan glaciers than cold environments of other locations. The data presented in this study have impli- cations for a better understanding of microbial diversity in cold springs on the Qinghai-Tibetan Plateau.展开更多
A new acyclic peroxide derivative asperoxide A(1),along with 13 known compounds,namely,microperfuranone(2),9-hydroxymicroperfuranone(3),gibellulin A(4),lecanoric acid(5),terrequinone A(6),sterigmatocystin(7),isosecost...A new acyclic peroxide derivative asperoxide A(1),along with 13 known compounds,namely,microperfuranone(2),9-hydroxymicroperfuranone(3),gibellulin A(4),lecanoric acid(5),terrequinone A(6),sterigmatocystin(7),isosecosterigmatocystin(8),arugosin C(9),curvularin(10),3,3'-diindolylmethane(11),austinol(12),austin(13),and dehydroaustin(14),were isolated and identified from the culture extract of Aspergillus nidulans SD-531,a fungus obtained from the deep-sea sediment of cold spring in the South China Sea.Their structures were determined based on detailed interpretation of nuclear magnetic resonance(NMR)spectroscopic and mass spectrometry data analysis.All the isolated compounds were evaluated for antimicrobial activities against human and aquatic bacteria as well as plant pathogenic fungi.Compounds 1–8,10,and 11 exhibited antimicrobial activities against some of the tested strains with minimum inhibitory concentration(MIC)values ranging from^2 to 64μg/mL.Compounds 4 and 6 displayed strongest activities among the tested samples and might be used as promising molecules for the development of natural antimicrobial agents.展开更多
Overview Cold Spring Harbor Asia conferences will be held at Suzhou Dushu Lake Conference Center in Suzhou, China, sixty miles west of Shanghai and in easy reach of international and domestic airports. Suzhou is an an...Overview Cold Spring Harbor Asia conferences will be held at Suzhou Dushu Lake Conference Center in Suzhou, China, sixty miles west of Shanghai and in easy reach of international and domestic airports. Suzhou is an ancient city known as the Venice of China, famous for its canals and private gardens and home to scholars for more than two millenia.展开更多
The conference will include eight oral sessions and one poster session.Many talks will be selected from the openly submittedabstracts on the basis of scientific merit and relevance.Social events throughout the confere...The conference will include eight oral sessions and one poster session.Many talks will be selected from the openly submittedabstracts on the basis of scientific merit and relevance.Social events throughout the conference provide ample opportunity forinformal interactions.Major topics on the conference include:neurogenesis,axon guidance,synapse formation,dendritemorphogenesis,developmental plasticity。展开更多
Continuous rainy and cold weather in Yiwu in early spring of 2009 was analyzed. The results showed that the continuous rainy and cold weather occurred after temperature increased in early days. It is mainly because th...Continuous rainy and cold weather in Yiwu in early spring of 2009 was analyzed. The results showed that the continuous rainy and cold weather occurred after temperature increased in early days. It is mainly because that the high geopotential height near Ural Mountains lasted for a long time, while the geopotential height was abnormally low in the east of central Asia. Meanwhile, the Iow-prassure trough in the south of Qinghai -Tibet Plateau was very active and moved towards the east frequently, and subtropical high was strong. Compared with continuous rainy and cold weather in early 2008, during the process of this continuous rainy and cold weather in 2009, the decrease in sea surface temperature of the middle and eastern Pacific Ocean near the equator was weaker; the blocking high pressure was slightly weaker, and the low pressure over Mongolia was strong; subtropical high was stronger and showed zonal distribution; south trough was slightly weaker. Compared with the previous continuous rainy and cold weather, the duration of this continuous rainy and cold weather in 2009 was not the longest, and its sunshine hours were not the least, but its temperature was higher, which might result from obvious increase of temperature in the early days. The research could provide scientific references for the prediction of continuous rainy and cold weather in future.展开更多
2020年3月18日中午至夜间,山西、河北、北京、天津和山东等地先后出现阵风10级及以上强风天气。利用风廓线雷达、国家级地面气象观测站和欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts, ECMWF)第五代大气...2020年3月18日中午至夜间,山西、河北、北京、天津和山东等地先后出现阵风10级及以上强风天气。利用风廓线雷达、国家级地面气象观测站和欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts, ECMWF)第五代大气再分析数据(ECMWF Reanalysis v5,ERA5)等资料,对强风过程的天气学成因进行了分析。结果表明:强风发生在低空暖脊异常发展的热力环境条件下,冷锋自黄土高原下到华北平原,中层锋消,垂直方向上发生“断裂”,低层冷锋先行侵入热低压,在锋生过程中发生。强风具有显著的非地转瞬变特征,低层强冷平流是强变压梯度产生的主要因素,变压风叠加在快速移动的冷锋系统中诱发大风,变压风是重要组成部分;低空动量下传效应引起低层风速波动,但不足以直接诱发强风。展开更多
基金supported by the National Key Research and Development Program of China (2017YFD0300408)the Major Research Projects of Anhui (202003b06020021)the Graduate Innovation Fund of Anhui Agricultural University (2020 ysj-5)。
文摘Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses of wheat spikelets at various positions,leaves,and stems and the interactions between them at physiological levels remain unclear.In the present study,two-year treatments at terminal spikelet stage under two temperatures(2 C,-2 C) and durations(1,2,and 3 days) were imposed in an artificial climate chamber to compare the effects of LSC on grain number and yield in the wheat cultivars Yannong 19(YN19,cold-tolerant) and Xinmai 26(XM26,cold-sensitive).The night temperature regimes were designed to reproduce natural temperature variation.LSC delayed plant growth and inhibited spike and floret differentiation,leading to high yield losses in both cultivars.LSC reduced dry matter accumulation(DMA,g) in spikes,stems,and leaves,reducing the DMA ratios of the spike to leaf and spike to stem.Plant cell wall invertase(CWINV) activity increased in upper and basal spikelets in YN19,whereas CWINV increased in middle spikelets in XM26.Under LSC,soluble sugar and glucose were transported and distributed mainly in upper and basal spikelets for glume and rachis development,so that spike development was relatively complete in YN19,whereas the upper and basal spikelets were severely damaged and most of the glumes in middle spikelets were relatively completely developed in XM26,resulting in pollen abortion mainly in upper and basal spikelets.The development of glumes and rachides was influenced and grain number per spike was decreased after LSC,with kernels present mainly in middle spikelets.Overall,reduced total DMA and dry matter partitioning to spikes under LSC results in poor spikelet development,leading to high losses of grain yield.
文摘The NCEP data were applied to analyze causes of 'late spring coldness' occurring twice in Dalian in late April and mid May of 2008.The results showed that the 500 hPa Baikal ridge of high pressure maintained or strengthened in a stable manner.The delivery of accumulated cold air toward southeast was along the northwest airstream before the ridge.Therefore,the ridge of high pressure over Lake Baikal provided access for the cold air southward so that the cold air could continue to decline,resulting in the appearance of low temperature in late April and formation of 'late spring coldness'.The Northeast cold vortex(NECV) occurred frequently in mid May.There was a high possibility for low temperature and pluvial damages over Dalian.Thus the phenomenon of 'late spring coldness' appeared again.
基金jointly supported by the National Key R&D Program of China [grant number 2016YFA0600701]the National Natural Science Foundation of China [grant numbers41675083 and 41210007]the CAS–PKU Joint Research Program
文摘This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving processes.During an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies and an anomalous anticyclone that continuously transport northern cold air to North China,causing significant,persistent,lower-than-normal daily temperatures.In fact,these positive SLP and anticyclonic wind anomalies begin to appear over northwestern Europe about 10 days prior to the ESCS.The anticyclonic wind anomalies keep moving southeastward and expand to the west of Lake Baikal until two days before the ESCS.Then,the center of the anomalous low-level anticyclone moves over Lake Baikal,inducing northerly wind anomalies that transport cold air into North China.In the following days,as the positive SLP anomalies weaken,the anomalous anticyclone and related northerly winds appear to wane,and the ESCS gradually comes to an end.The results may prove meaningful for the prediction and early warning of ESCSs.
基金supported by grants from National Science Foundation of China(Grant Nos.41030211 and 41002123)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Edncation Ministry,Research Fund for the Doctoral Program of Higher Education of China(Grant No. 20100022120009)+1 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.2010ZY16 and 2011YXL03)the Teaching Laboratory Funds from China University of Geosciences,Beijing
文摘The microbial diversity in Wuli Area, Qinghai-Tibetan Plateau was investigated using 16S rRNA gene phylogenetic analyses. A total of 117 bacterial and 66 archaeal 16S rRNA gene clones were obtained from the Wuli cold springs, The bacterial clones could be classified into Proteobacteria, Acid- obacteria, Deinococci, Sphingobacteria, Flavobacteria, Nitrospirae, Actinobacteria, Gemmatimona- detes, and unclassified-bacteria; and the archaeal clones could be classified into Crenarchaeota and Thaumarchaeota. Among the major groups, Proteobacteria and Crenarchaeota were dominant in the bacterial and archaeal 16S rRNA gene clone libraries, respectively. The clone sequences obtained in Wuli cold springs were closely related to those from cold habitats, such as snow/ice/soils on high mountains or at high latitude. Especially, the microbial community composition of Wuli Area was more similar to that in Tibetan glaciers than cold environments of other locations. The data presented in this study have impli- cations for a better understanding of microbial diversity in cold springs on the Qinghai-Tibetan Plateau.
基金the National Key R&D Program of China(No.2018YFC0310800)。
文摘A new acyclic peroxide derivative asperoxide A(1),along with 13 known compounds,namely,microperfuranone(2),9-hydroxymicroperfuranone(3),gibellulin A(4),lecanoric acid(5),terrequinone A(6),sterigmatocystin(7),isosecosterigmatocystin(8),arugosin C(9),curvularin(10),3,3'-diindolylmethane(11),austinol(12),austin(13),and dehydroaustin(14),were isolated and identified from the culture extract of Aspergillus nidulans SD-531,a fungus obtained from the deep-sea sediment of cold spring in the South China Sea.Their structures were determined based on detailed interpretation of nuclear magnetic resonance(NMR)spectroscopic and mass spectrometry data analysis.All the isolated compounds were evaluated for antimicrobial activities against human and aquatic bacteria as well as plant pathogenic fungi.Compounds 1–8,10,and 11 exhibited antimicrobial activities against some of the tested strains with minimum inhibitory concentration(MIC)values ranging from^2 to 64μg/mL.Compounds 4 and 6 displayed strongest activities among the tested samples and might be used as promising molecules for the development of natural antimicrobial agents.
文摘Overview Cold Spring Harbor Asia conferences will be held at Suzhou Dushu Lake Conference Center in Suzhou, China, sixty miles west of Shanghai and in easy reach of international and domestic airports. Suzhou is an ancient city known as the Venice of China, famous for its canals and private gardens and home to scholars for more than two millenia.
文摘The conference will include eight oral sessions and one poster session.Many talks will be selected from the openly submittedabstracts on the basis of scientific merit and relevance.Social events throughout the conference provide ample opportunity forinformal interactions.Major topics on the conference include:neurogenesis,axon guidance,synapse formation,dendritemorphogenesis,developmental plasticity。
文摘Continuous rainy and cold weather in Yiwu in early spring of 2009 was analyzed. The results showed that the continuous rainy and cold weather occurred after temperature increased in early days. It is mainly because that the high geopotential height near Ural Mountains lasted for a long time, while the geopotential height was abnormally low in the east of central Asia. Meanwhile, the Iow-prassure trough in the south of Qinghai -Tibet Plateau was very active and moved towards the east frequently, and subtropical high was strong. Compared with continuous rainy and cold weather in early 2008, during the process of this continuous rainy and cold weather in 2009, the decrease in sea surface temperature of the middle and eastern Pacific Ocean near the equator was weaker; the blocking high pressure was slightly weaker, and the low pressure over Mongolia was strong; subtropical high was stronger and showed zonal distribution; south trough was slightly weaker. Compared with the previous continuous rainy and cold weather, the duration of this continuous rainy and cold weather in 2009 was not the longest, and its sunshine hours were not the least, but its temperature was higher, which might result from obvious increase of temperature in the early days. The research could provide scientific references for the prediction of continuous rainy and cold weather in future.
文摘2020年3月18日中午至夜间,山西、河北、北京、天津和山东等地先后出现阵风10级及以上强风天气。利用风廓线雷达、国家级地面气象观测站和欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts, ECMWF)第五代大气再分析数据(ECMWF Reanalysis v5,ERA5)等资料,对强风过程的天气学成因进行了分析。结果表明:强风发生在低空暖脊异常发展的热力环境条件下,冷锋自黄土高原下到华北平原,中层锋消,垂直方向上发生“断裂”,低层冷锋先行侵入热低压,在锋生过程中发生。强风具有显著的非地转瞬变特征,低层强冷平流是强变压梯度产生的主要因素,变压风叠加在快速移动的冷锋系统中诱发大风,变压风是重要组成部分;低空动量下传效应引起低层风速波动,但不足以直接诱发强风。
