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The relationship between the canonical ENSO and the phase transition of the Antarctic oscillation at the quasi-quadrennial timescale

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Acta Oceanologica Sinica 2010年第6期29卷 26-34页

作者： liu changzheng xue feng National Climate Center Beijing 100081 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

A correlation analysis is performed to investigate the relationship between El Nino-Southern Oscillation （ENSO） and the Antarctic oscillation （AAO） at the quasi-quadrennial （QQ） *** is found that the cold tongue index （CTI） and the AAO index （AAOI） are negatively correlated with about a 7-month lead-time,while they are positively correlated with about a 15-month *** further explore this relationship,complex empirical orthogonal function analysis is employed in the QQ sea level pressure （SLP） anomalies from 1951 to *** results indicate that,during the ENSO cycle,there exists one kind of global tropical wave of wavenumber 1 （GTW1） propagating *** the traveling of GTW1,the tropical SLP anomaly tends to intrude into the southern ***,three strong signals travel synchronously along the circumSouth-Pacific path,and a relatively weak signal extends eastward and poleward over the South Ocean in the Atlantic-Indian Ocean *** the propagation of these signals,the AAO phase tends to be reversed *** a result,there exists an evident lead-lag correlation between CTI and *** can be concluded that ENSO plays a key role in the phase transition of AAO at the QQ *** is also noticed that this regular relationship is only evident in the canonical ENSO events,for which sea surface temperature （SST） anomalies extend westward from the tropical eastern *** the other hand,the similar relationships are not found among those atypical ENSO events for which SST anomalies spread eastward from the central Pacific,such as the 1982-1983 ENSO event.

关键词： ENSO Antarctic oscillation the quasi-quadrennial timescale the global tropical wave of wavenumber 1

Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth sciences 2005年第8期48卷 1270-1279页

作者： liu feng1,2, HU Fei2 & ZHU Jiang2 1. College of Environmental sciences, Peking University, beijing 100871, china 2. LAPC, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china College of Environmental sciences Peking University Beijing China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

Influence of interannual variability of Antarctic oscillation on mei-yu along the Yangtze and Huaihe River valley and its importance to prediction

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chinese Science Bulletin 2003年第S2期48卷 61-67页

作者： GAO Hui~(1,2), xue feng~1 WANG Huijun~1 1. institute of atmospheric physics, chinese academy of sciences, beijing 100029, china 2. Department of atmospheric sciences, Nanjing institute of Meteorology, Nanjing 210044. china chinese Acad Sci Inst Atmospher Phys Beijing 100029 Peoples R China Nanjing Inst Meteorol Dept Atmospher Sci Nanjing 210044 Peoples R China

Both correlation analysis and case study indi-cate that Antarctic oscillation (AAO) is closely related withsummer rainfall in eastern china. When AAO is stronger inboreal spring, especially in May, there is more mei-yu rain-fall in summer with a longer period along the Yangtze andHuaihe River valley. In contrast, there is less rainfall with ashorter period corresponding to a weaker AAO. Besides, ananomalous AAO changes the position and intensity of severalcirculation systems, which are important to summer rainfallalong the Yangtze and Huaihe River valley. Furthermore, theAntarctic sea ice is negatively correlated with the intensity ofAAO with a 6-month leading time. The result in this studyprovides a new method for the prediction of mei-yu.

关键词： Antarctic oscillation interannual variability mei-yu Antarctic sea ice.

THE RESPONSES OF THE THIRD GENERATION OF IAP/LASG OCEANIC GCM TO DIFFERENT EXTERNAL FORCING

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Journal of Hydrodynamics 2001年第3期13卷 107-114页

作者： Li Wei, liu Hai long, Zhang xue hong LASG institute of atmospheric physics, chinese academy of sciences, beijing 100029, china Fang Guo hong institute of Oceanology, chinese academy of sciences, Qingdao 266071, china Key Laboratory of Marine Scienc LASG Inst. of atmospheric physics Chinese Acad. of Sci. Beijing 100029 China

Forced by different wind stress as well as different surface heat flux, three 10 year integrations using L30T63 oceanic GCM are carried out. The annual mean state, seasonal cycle and interannual variability of the upper ocean temperature over the tropical Pacific are examined. In the case of annual mean state of sea surface temperature, relults from D15c and D15e are alike and have good agreement with NCEP data. Defects in D15d include the excessively higher SST over warm pool region and higher SST along the eastern coast. The corresponding westward displacement of cold water is also noticeable. All the experiments represent the annual cycle of SST in the eastern equatorial Pacific while the amplitudes are weaker compared to NCEP data. The intensity of interannual variability of SST in eastern equatorial Pacific is markedly improved D15d and is perfectly comparative with that from NCEP data. The eastward propagations of the interannual variability of upper ocean heat content along the equator in 1982/1983 E1 Nio are well represented in all experiments. On the onset stage of 1982/1983 E1 Nio, the modeled interannual variabilities of SST and heat content are generally the same among all experiments. It is the weakest interannual variability of surface heat flux, which damps SST variability during the mature phase of E1 Nio, that results in a most intensified SST variability in D15d.

关键词： Oceanic GCM tropical pacific SST

Risk Factors of Depression Screened by Two-Sample Mendelian Randomization Analysis:A Systematic Review

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Biomedical and Environmental sciences 2024年第1期37卷 85-95页

作者： WANG Han Lin xue Yan feng CUI Bao Qiu liu Hong SHEN Xin Xin Shandong Provincial Research Center for Bioinformatic Engineering and Technique School of Life SciencesShandong University of TechnologyZibo 255049ShandongChina Shanxi Province Cancer Hospital/Shanxi Hospital Affiliated to Cancer Hospital Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical UniversityTaiyuan 030013ShanxiChina State Key Laboratory of Infectious Disease Prevention and Control National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China

Objective This study explored the potentially modifiable factors for depression and major depressive disorder(MDD)from the MR-Base database and further evaluated the associations between drug targets with *** We analyzed two-sample of Mendelian randomization(2SMR)using genetic variant depression(n=113,154)and MDD(n=208,811)from Genome-Wide Association Studies(GWAS).Separate calculations were performed with modifiable risk factors from MR-Base for 1,001 *** MR analysis was performed by screening drug targets with MDD in the DrugBank database to explore the therapeutic targets for *** variance weighted(IVW),fixed-effect inverse variance weighted(FE-IVW),MR-Egger,weighted median,and weighted mode were used for complementary *** The potential causal relationship between modifiable risk factors and depression contained 459 results for depression and 424 for ***,the associations between drug targets and MDD showed that SLC6A4,GRIN2A,GRIN2C,SCN10A,and IL1B expression are associated with an increased risk of *** contrast,ADRB1,CHRNA3,HTR3A,GSTP1,and GABRG2 genes are candidate protective factors against *** This study identified the risk factors causally associated with depression and MDD,and estimated 10 drug targets with significant impact on MDD,providing essential information for formulating strategies to prevent and treat depression.

关键词： Risk factors Drug targets Depression Major depressive disorder Two-sample Mendelian randomization

Whole-genome sequencing in medicinal plants:current progress and prospect

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Science china(Life sciences) 2024年第2期67卷 258-273页

作者： Yifei Pei Liang Leng Wei Sun Baocai liu xue feng Xiwen Li Shilin Chen institute of chinese Materia Medica China Academy of Chinese Medical SciencesBeijing 100700China institute of Herbgenomics Chengdu University of Traditional Chinese MedicineChengdu 611137China Innovative institute of chinese Medicine and Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 611137China institute of Agricultural Bioresource Fujian Academy of Agricultural SciencesFuzhou 350003China

Advancements in genomics have dramatically accelerated the research on medicinal plants,and the development of herbgenomics has promoted the“Project of 1K Medicinal Plant Genome”to decipher their genetic ***,it is difficult to obtain their high-quality whole genomes because of the prevalence of polyploidy and/or high genomic *** genomes of 123 medicinal plants were published until September *** published genome sequences were investigated in this review,covering their classification,research teams,ploidy,medicinal functions,and sequencing *** than 1,000 institutes or universities around the world and 50 countries are conducting research on medicinal plant *** species account for a majority of sequenced medicinal *** whole genomes of plants in the Poaceae family are the most *** 40%of the published papers studied species with tonifying,replenishing,and heat-cleaning medicinal *** plants are still in the process of domestication as compared with crops,thereby resulting in unclear genetic backgrounds and the lack of pure lines,thus making their genomes more difficult to *** addition,there is still no clear routine framework for a medicinal plant to obtain a high-quality whole ***,a clear and complete strategy has been originally proposed for creating a high-quality whole genome of medicinal ***,whole genome-based biological studies of medicinal plants,including breeding and biosynthesis,were *** also advocate that a research platform of model medicinal plants should be established to promote the genomics research of medicinal plants.

关键词： herbgenomics whole genome high throughput sequencing research strategy model species application

Plutonium utilization in a small modular molten-salt reactor based on a batch fuel reprocessing scheme

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Nuclear Science and Techniques 2024年第4期35卷 15-28页

作者： xue-Chao Zhao Rui Yan Gui-feng Zhu Ya-Fen liu Jian Guo Xiang-Zhou Cai Yang Zou Shanghai institute of Applied physics Chinese Academy of SciencesShanghai 201800China CAS Innovative Academies in TMSR Energy System Chinese Academy of SciencesShanghai 201800China University of chinese academy of sciences Beijing 100049China

A molten salt reactor(MSR)has outstanding features considering the application of thorium fuel,inherent safety,sustainability,and resistance to ***,fissile material^(233)U is significantly rare at the current stage,thus it is difficult for MSR to achieve a pure thorium-uranium fuel ***,using plutonium or enriched uranium as the initial fuel for MSR is more *** this study,we aim to verify the feasibility of a small modular MSR that utilizes plutonium as the starting fuel(SM-MSR-Pu),and highlight its advantages and ***,the structural design and fuel management scheme of the SM-MSR-Pu were ***,the neutronic characteristics,such as the graphite-irradiation lifetime,burn-up performance,and coefficient of temperature reactivity were calculated to analyze the physical characteristics of the *** results indicate that plutonium is a feasible and advantageous starting fuel for a SM-MSR;however,there are certain shortcomings that need to be *** a 250 MWth SM-MSR-Pu,approximately 288.64 kg^(233)U of plutonium with a purity of greater than 90% is produced while 978.00 kg is burned every ten *** temperature reactivity coefficient decreases from -4.0 to -6.5 pcm K^(-1) over the 50-year operating time,which ensures a long-term safe ***,the amount of plutonium and accumulation of minor actinides(MAs)would increase as the burn-up time increases,and the annual production and purity of^(233)U will *** achieve an optimal burn-up performance,setting the entire operation time to 30 years is ***,more than 3600 kg of plutonium eventually accumulate in the *** research is required to effectively utilize this accumulated plutonium.

关键词： Molten salt fuel Plutonium utilization ^(233)U TRUs mole fraction Temperature feedback coefficient

Molecular quantification of herbs(Herb-Q):a pyrosequencingbased approach and its application in Pinellia ternata

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chinese Journal of Natural Medicines 2024年第7期22卷 663-672页

作者： PEI Yifei liu Ziyi YU Dade ZHANG Xiangyu SUN Wei CHEN Xiaofang feng xue LI Xiwen institute of chinese Materia Medica China Academy of Chinese Medical SciencesBeijing 100700China Bijie institute of Traditional chinese Medicine Bijie 551700China The Key Laboratory for Health Industry of Bijie Bijie Medical CollegeBijie 551700China

Variations in herb dosage due to species adulteration and dosing inaccuracies can substantially affect clinical safety and *** species quantification remains challenging,as current methods often yield inconsistent *** study introduces a novel pyrosequencing-based technique,termed herb molecular quantification(Herb-Q),designed to precisely quantify herbal *** evaluated its effectiveness using Pinellia ternata and five of its ***,we assessed commonly used DNA barcodes with sequences from a public database,identifying two candidate regions,Maturase K(matK)and internal transcribed spacer 2(ITS2),for screening specific single nucleotide polymorphism(SNP)loci,allowing for species-specific *** loci were validated by amplifying and sequencing genomic material from collected *** validation studies showed that Herb-Q demonstrated excellent linearity,accuracy,repeatability,and detection *** established quantitative standard curves with high R^(2)values(>0.99)to enable precise species quantification,which were combined with external standards to provide clear and accurate visual quantification *** average bias in quantifying the tuber of *** was 2.38%,confirming that Herb-Q can accurately identify and quantify herbal product ***,the entire quantification process took less than 4 *** study presents a novel,rapid method for accurately quantifying species in herbal products and advances the application of DNA barcoding from species identification to quantitative detection.

关键词： Quantification Adulterant DNA barcodes Single nucleotide polymorphism

EXPERIMENTS OF SEA ICE SIMULATION

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Journal of Hydrodynamics 2005年第6期17卷 686-692页

作者： liu Xi-ying State Key Laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics （LASG） Institute of Atmospheric Physics （IAP） Chinese Academy of Sciences Beijing 100029 China

As a substitute for the original displaced pole grids, a simple rotated spherical coordinate system was intro duced into the Community Sea Ice Model version 4（CSIM4）, which is a component of the Community Climate System Model（CCSM） of the American National Center of atmospheric Researeh（NCAR）, to deal with the ＂pole problems＂. In the new coordinates, both the geographical North Pole and South Pole lie in the model equator and grid sizes near the polar region are more uniform. With reanalysis dataset of American National Centers for Environment Prediction （NCEP） and Levitus dataset without considering sub-mixed layer heat flux, the model was integrated for 100 years with thermodynamics *** involved only in the former 49 years and both dynamic and thermodynamic processes involved in the left time. Inner consistency of model results was checked with no contradiction found. The results of last 10 years＇ model output were analyzed and it is shown that the simulated sea ice seasonal variation is rational whereas sea ice extent in the Barcnts Sea in winter is larger than that of observation, Numerical experiment on influence of sub-mixed layer heat flux was also carried out and it is shown that the sub-mixed layer heat flux can modulate seasonal variation of sea ice greatly. As a model component, the sea ice model with rotated spherical coordinates was coupled with other models （the oceanic general cir culation model is the LASG/IAP Climate System Ocean Model （LICOM） with reduced grid, other models are components of NCAR CCSM2） forming a climate system model and its preliminary results were also given briefly.

关键词： sea ice numerical simulation climate system model