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The influence of the Madden-julian Oscillation activity anomalies on Yunnan's extreme drought of 2009-2010

Science China Earth Sciences 2012年第1期55卷 98-112页

作者： LU junMei ju jianhua REN juZhang GAN WeiWei Chinese Academy of Meteorological Sciences Beijing 100081China Yunnan Provincial Meteorological Service Kunming 650034China Yunnan Institute of Meteorology Kunming 650034China Department of Atmospheric Sciences Yunnan UniversityKunming 650091China

Yunnan Province of China suffered a record-breaking drought that persisted from autumn 2009 into spring 2010. The present study examined the physical causes of this extreme drought event in terms of persistent anomalies of intraseasonal oscillation in the tropical atmosphere （the Madden-julian Oscillation hereafter the MJO）. The results show that the occurrence of severe drought in Yunnan was caused directly by deficient rainfall lasting from the summer of 2009 to the spring of 2010. Further ex- ploration reveals a persistent positive variation of MJO index 1 from june to October. Accordingly, the convective activity over the Bay of Bengal （BOB） weakened continuously, and then an anomalous descending airflow was induced over the tropi- cal Indian Ocean, resulted in the anomalous weakening of vertical Asian monsoon circulation in South Asia. Consequently, the transport of water vapor from the tropical Indian Ocean to Yunnan decreased abnormally, leading to persistent below-normai rainfall over Yunnan from summer to autumn in 2009. As a result, a severe drought began to appear in autumn. In the winter of 2009-2010, MJO index 1 remained persistently positive, indicating the continuous weakening of convective activity over the BOB. The atmospheric circulation associated with the persistent positive anomalies in the MJO also demonstrated anomalous patterns. Specifically, there was an anomalous high-pressure ridge stretching from South Asia through the Tibetan Plateau and into the western part of southwestem China. This indicates that the atmospheric circulation over Yunnan was dominated by vertical descending airflow in the high-pressure ridge. Simultaneously, the India-Burma trough was weakened, which resulted in unfavorable conditions for the transport of water vapor from the BOB to Yunnan, causing the observed persistent deficient precipitation in winter and the subsequently intensified drought. Therefore, the persistent anomalies in MJO activity in the tropical atmos

关键词： Yunnan extreme drought MJO persistent anomalies

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Differences between dynamics factors for interannual and decadal variations of rainfall over the Yangtze River valley during flood seasons

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Chinese Science Bulletin 2006年第8期51卷 994-999页

作者： PING Fan LUO Zhexian ju jianhua Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Nanjing University of Information Science & Technology Nanjing 210044 China China Meteorological Administration Training Center Beijing 100081 China

The rainfall over the Yangtze River val- ley during flood seasons (june to july) shows both interannual and decadal variations. The rainfall has been increasing since 1990, showing a decadal sig- nal. The variations of rainfall are influenced by the multi-scale interactions in the atmosphere-ocean coupled climate system. The rainfall, SST, and cir- culation are analyzed with the Chinese 160 station data, and other observational/reanalysis data, re- spectively. The separation between the interannual and decadal variations is carried out. The key areas affecting the Yangtze rainfall are the western Pacific warm pool on the interannual time scale and the EINO3 area on the decadal time scale, respectively. The circulation anomaly associated with the interan- nual variation occurs in the upper troposphere whereas that associated with the decadal variation appears in the lower troposphere.

关键词：长江流域降雨量动力学因素比较分析

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Influence of Springtime Atlantic SST on ENSO:Role of the Madden-julian Oscillation

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Journal of Meteorological Research 2018年第3期32卷 380-393页

作者： Xin YAN juzhang REN jianhua ju Song YANG School of Atmospheric Sciences Sun Yat-sen UniversityGuangzhou 510275 Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen UniversityGuangzhou 510275 Yunnan Research Institute of Meteorology Kunming 650034 Yunnan Provincial Meteorological Bureau Kunming 650034

Increased evidence has shown the important role of Atlantic sea surface temperature(SST) in modulating the El Nio-Southern Oscillation(ENSO). Persistent anomalies of summer Madden-julian Oscillation(MJO) act to link the Atlantic SST anomalies(SSTAs) to ENSO. The Atlantic SSTAs are strongly correlated with the persistent anomalies of summer MJO, and possibly affect MJO in two major ways. One is that an anomalous cyclonic(anticyclonic) circulation appears over the tropical Atlantic Ocean associated with positive(negative) SSTA in spring, and it intensifies(weakens) the Walker circulation. Equatorial updraft anomaly then appears over the Indian Ocean and the eastern Pacific Ocean, intensifying MJO activity over these regions. The other involves a high pressure(low pressure) anomaly associated with the North Atlantic SSTA tripole pattern that is transmitted to the mid-and low-latitudes by a circumglobal teleconnection pattern, leading to strong(weak) convective activity of MJO over the Indian Ocean. The above results offer new viewpoints about the process from springtime Atlantic SSTA signals to summertime atmospheric oscillation, and then to the MJO of tropical atmosphere affecting wintertime Pacific ENSO events, which connects different oceans.

关键词： Madden-julian Oscillation(MJO) Atlantic sea surface temperature anomaly(SSTA) Walker circulation teleconnection El Nio-Southern Oscillation(ENSO)

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Characterization of the depsidone gene cluster reveals etherification,decarboxylation and multiple halogenations as tailoring steps in depsidone assembly

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Acta Pharmaceutica Sinica B 2023年第9期13卷 3919-3929页

作者： Jiafan Yang Zhenbin Zhou Yingying Chen Yongxiang Song jianhua ju CAS Key Laboratory of Tropical Marine Bio-resources and Ecology RNAM Center for Marine MicrobiologyGuangdong Key Laboratory of Marine Materia MedicaSouth China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Beijing 110039China

Depsides and depsidones have attracted attention for biosynthetic studies due to their broad biological activities and structural *** structure-activity relationships indicated that triple halogenated depsidones display the best anti-pathogenic ***,the gene cluster and the tailoring steps responsible for halogenated depsidone nornidulin(3)remain *** this study,we disclosed the complete biosynthetic pathway of the halogenated depsidone through in vivo gene disruption,heterologous expression and in vitro biochemical *** demonstrated an unusual depside skeleton biosynthesis process mediated by both highly-reducing polyketide synthase and nonreducing polyketide synthase,which is distinct from the common depside skeleton *** skeleton was subsequently modified by two in-cluster enzymes DepG and DepF for the ether bond formation and decarboxylation,*** addition,the decarboxylase DepF exhibited substrate promiscuity for different scaffold ***,and interestingly,we discovered a halogenase encoded remotely from the biosynthetic gene cluster,which catalyzes triple-halogenation to produce the active end product nornidulin(3).These discoveries provide new insights for further understanding the biosynthesis of depsidones and their derivatives.

关键词： Depside and depsidone Polyketide synthase Tailoring enzymes Multiple-halogenated Antibacterial activity

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Enzymatic Synthesis of a Diastereomer of Neoabyssomicin Derivative Using the Diels-Alderase AbyU

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Chinese Journal of Chemistry 2021年第7期39卷 1871-1877页

作者： Wenjuan Ding Changbiao Chi Xiaoyi Wei Changli Sun Jiajia Tu Ming Ma Qinglian Li jianhua ju CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology Guangdong Key Laboratory of Marine Materia MedicaRNAM Center for Marine MicrobiologySouth China Sea Institute of OceanologyChinese Academy of Sciences164 West Xingang RoadGuangzhouGuangdong510301 China College of Oceanology University of Chinese Academy of Sciences19 Yuquan RoadBeijing100049 China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) No.1119Haibin Rd.Nansha DistrictGuangzhouGuangdong510301 China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing100191 China Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhouGuangdong510650 China

Main observation and conclusion The enzyme AbyU catalyses a Diels-Alder(DA)reaction during abyssomicin C *** this study,AbyU is shown to convert the native substrate of another Diels-Alderase(DAase),AbmU,to a new abys... 详细信息

关键词： Biosynthesis Bioorganic chemistry Enzyme catalysis Neoabyssomicin Diels-Alderase

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Biosynthesis of Antituberculosis Cyclicpeptide Ilamycins

Biosynthesis of Antituberculosis Cyclicpeptide Ilamycins

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中国化学会第十一届全国天然有机化学学术会议

作者： jianhua ju CAS Key Laboratory of Marine Bio-resources and Ecology South China Sea Institute of Oceanology Chinese Academy of Sciences

＜正＞Natural products remain the best sources for drugs or drug *** actinomycetes,the underexplored ecological niches,have emerged as an exciting resource for novel bioactive natural products *** advances in deciphering and engineering the biosynthetic pathway governing natural product biosynthesis provide an alternative strategy to optimize the structures of complex natural *** examples from our

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The Variations of Dominant Convection Modes over Asia, Indian Ocean, and Western Pacific Ocean during the Summers of 1997-2004

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Advances in Atmospheric Sciences 2010年第4期27卷 901-920页

作者：李跃凤肖子牛琚建华胡国权 Laboratory for Climate Studies National Climate Center China Meteorological Administration Training Centre China Meteorological Administration

The NOAA daily outgoing longwave radiation （OLR） and the Global Precipitation Climatology Project （GPCP）daily precipitation data are used to study the variation of dominant convection modes and their relationships over Asia, the Indian Ocean, and the western Pacific Ocean during the summers from 1997 to 2004. Major findings are as follows：（1） Regression analysis with the OLR indicates the convective variations over Asian monsoon region are more closely associated with the convective activities over the western subtropical Pacific （WSP） than with those over the northern tropical Indian Ocean （NTIO）. （2） The EOF analysis of OLR indicates the first mode （EOF1） exhibits the out-of-phase variations between eastern China and India, and between eastern China and the WSP. The OLR EOF1 primarily exhibits seasonal and even longer-term variations. （3） The OLR EOF2 mostly displays in-phase convective variations over India, the Bay of Bengal, and southeastern China. A wavelet analysis reveals intraseasonal variation （ISV） features in 2000, 2001, 2002, and 2004. However, the effective ISV does not take place in every year and it seems to occur only when the centers of an east-west oriented dipole reach enough intensity over the tropical Indian and western Pacific Oceans. （4） The spatial patterns of OLR EOF3 are more complicated than those of EOF1 and EOF2, and an effective ISV is noted from 1999 to 2004. The OLR EOF3 implies there is added complexity of the OLR pattern when the effective ISV occurs. （5） The correlation analysis suggests the precipitation over India is more closely associated with the ISV, seasonal variations, and even longer-term variations than precipitation occurring over eastern China.

关键词： intraseasonal variation dominant convection modes correlation

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夏季MJO持续异常的主要特征分析

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大气科学 2016年第5期40卷 1048-1058页

作者：严欣琚建华云南大学资源环境与地球科学学院昆明650000 云南省气象局昆明650000

在MJO传播过程中,其活动中心并不总是规律地沿赤道东传。本文通过资料分析发现,夏季MJO的活动中心会出现东传停滞的情况,表现为MJO在赤道太平洋持续异常活跃或者在印度洋持续异常活跃两种形式。为更好描述MJO这种东传不明显的异常特征,... 详细信息

在MJO传播过程中,其活动中心并不总是规律地沿赤道东传。本文通过资料分析发现,夏季MJO的活动中心会出现东传停滞的情况,表现为MJO在赤道太平洋持续异常活跃或者在印度洋持续异常活跃两种形式。为更好描述MJO这种东传不明显的异常特征,本文定义了一个描述MJO持续异常的指数,并据此对夏季MJO持续异常的主要特征进行分析。通过小波分析的方法,发现夏季MJO持续异常时其振荡周期会出现缩短或变弱。通过对MJO持续异常状况下的大气环流进行合成对比分析后发现,夏季MJO的持续异常会对热带大气环流造成显著的影响。具体表现为:MJO夏季在赤道太平洋(印度洋)持续活跃的时候,赤道沃克环流减弱(增强),西太平洋哈得来环流增强(减弱),西太平洋副高位置偏北(偏南),赤道太平洋(印度洋)高层辐散且对流活跃。

关键词： MJO 持续异常大气环流季节内振荡

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EmbB and EmbC regulate the sensitivity of Mycobacterium abscessusto echinomycin

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mLife 2024年第3期3卷 459-470页

作者： Jing He Yamin Gao Jingyun Wang H.M.Adnan Hameed Shuai Wang Cuiting Fang Xirong Tian Jingran Zhang Xingli Han Yanan ju Yaoju Tan junying Ma jianhua ju Jinxing Hu Jianxion Liu Tianyu Zhang Institute of Physical Science and Information Technology Anhui UniversityHefeiChina State Key Laboratory of Respiratory Disease Guangzhou Institutes of Biomedicine and HealthChinese Academy of SciencesGuangzhouChina Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Diseases Guangzhou Institutes of Biomedicine and HealthChinese Academy of SciencesGuangzhouChina China-New Zealand Joint Laboratory on Biomedicine and Health Guangzhou Institutes of Biomedicine and HealthChinese Academy of SciencesGuangzhouChina University of Chinese Academy of Sciences BejingChina School of Pharmacy Institute of Marine DrugGuangxi University of Traditional Chinese MedicineNanningChina CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology RNAM Center for Marine MicrobiologyGuangdong Key Laboratory of Marine Materia MedicaSouth China Sea Institute of OceanologyChinese Academy of SciencesGuangzhouChina School of Life Sciences University of Science and Technology of ChinaHefeiChina State Key Laboratory of Respiratory Disease Guangzhou Chest HospitalGuangzhouChina

Treatment of Mycobacterium abscessus(Mab)infections is very challenging due to its intrinsic resistance to most available ***,it is crucial to discover novel anti-Mab *** this study,we explored an intrinsic resistance mechanism through which Mab resists echinomycin(ECH).ECH showed activity against Mab at a minimum inhibitory concentration(MIC)of 2μg/ml.A embC strain in which the embC gene was knocked out showed hypersensitivity to ECH(MIC:0.0078-0.0156μg/ml).The MICs of ECH-resistant strains screened with reference to AembC ranged from 0.25 to 1μg/*** in EmbB,including D306A,D306N,R350G,V555l,and G581S,increased the Mab's resistance to ECH when overexpressed in AembC individually(MIC:0.25-0.5μg/ml).These EmbB mutants,edited using the CRISPR/Cpf1 system,showed heightened resistance to ECH(MIC:0.25-0.5μg/ml).The permeability of these Mab strains with edited genes and overexpression was reduced,as evidenced by an ethidium bromide accumulation assay,but it remained significantly higher than that of the parent *** summary,our study demonstrates that ECH exerts potent anti-Mab activity and confirms that EmbB and EmbC are implicated in Mab's sensitivity to *** in EmbB may partially compensate foralossof EmbCfunction.

关键词： echinomycin EmbB EmbC functional compensation Mycobacterium abscessus

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Member of Editorial Board of Rising Stars

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Chinese Journal of Chemistry 2018年第6期36卷 557-557页

作者： jianhua ju Professor CAS Key Laboratory of Marine Bio-resources and Ecology South China Sealnstitute of Oceanology CAS

Discovery and Biosynthesis of Marine Derived Bioactive Natural Products It has been demonstrated that natural products still play a pivotal role in new drug discovery. The novel scaffolds found within nature far exceed the imagination and synthetic capabilities of chemists, The underexplored marine microorganisms have been recognized as an exciting resource in supplying novel chemoWpes. We are focusing on the screening, fermentation, and discovery of bioactive natural products from marine actinobacteria and fungi, and therefore to obtain fundamentally new, clinically useful drug leads.[1,2]

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