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Chinese Chemical Letters 2022年第2期33卷 855-858页

作者： Yanhui Guo Yunyun Liu Jie-Ping Wan College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China

The selective synthesis of N^(2)-sulfonyl and N^(2)-H 1,2,3-triazoles via organocatalytic annulation of enaminone/enaminoester with sulfonyl azide has been realized. The unconventional selectivity providing N^(2)-sulfoyl 1,2,3-triazoles takes place in pure water, wherein the hydrogen bond effect between water and the intermediate resulting from enamine-azide corporation accounts for the novel reaction selectivity. On the other hand, the reactions conducted in DMSO specifically afford N^(2)-H 1,2,3-triazoles in the absence of such hydrogen bond effect.

关键词： Enaminone Annulation N^(2)-sulfonyl 1,2,3-triazole Selectivity Green synthesis Sulfonyl azide

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脂联素与糖尿病视网膜病变相关性研究现状

中华眼底病杂志 2017年第3期33卷 324-327页

作者：李芸云刘宁朴首都医科大学附属北京同仁医院北京同仁眼科中心北京市眼科学与视觉科学重点实验室 100730

糖尿病视网膜病变（DR）发病机制尚不明确，炎症反应、视网膜血管渗漏及视网膜新生血管化是其主要特征。脂联素（APN）是由脂肪细胞分泌的一种内源性生物活性蛋白，具有增加胰岛素敏感性、调节血糖血脂代谢、抗炎、抗新生血管化等作用... 详细信息

糖尿病视网膜病变（DR）发病机制尚不明确，炎症反应、视网膜血管渗漏及视网膜新生血管化是其主要特征。脂联素（APN）是由脂肪细胞分泌的一种内源性生物活性蛋白，具有增加胰岛素敏感性、调节血糖血脂代谢、抗炎、抗新生血管化等作用，可能参与DR的发生发展。了解APN与DR相关性研究现状，可为进一步研究DR发病机制提供新的思路。

关键词：糖尿病视网膜病变,病因学脂联素综述

The Record-breaking Mei-yu in 2020 and Associated Atmospheric Circulation and Tropical SST Anomalies

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Advances in Atmospheric Sciences 2021年第12期38卷 1980-1993页

作者： Yihui DING Yunyun Liu Zeng-Zhen HU National Climate Center China Meteorological AdministrationBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China Climate Prediction Center NCEP/NOAACollege ParkMD 20740USA

The record-breaking mei-yu in the Yangtze-Huaihe River valley(YHRV)in 2020 was characterized by an early onset,a delayed retreat,a long duration,a wide meridional rainbelt,abundant precipitation,and frequent heavy rainstorm processes.It is noted that the East Asian monsoon circulation system presented a significant quasi-biweekly oscillation(QBWO)during the mei-yu season of 2020 that was associated with the onset and retreat of mei-yu,a northward shift and stagnation of the rainbelt,and the occurrence and persistence of heavy rainstorm processes.Correspondingly,during the mei-yu season,the monsoon circulation subsystems,including the western Pacific subtropical high(WPSH),the upper-level East Asian westerly jet,and the low-level southwesterly jet,experienced periodic oscillations linked with the QBWO.Most notably,the repeated establishment of a large southerly center,with relatively stable latitude,led to moisture convergence and ascent which was observed to develop repeatedly.This was accompanied by a long-term duration of the mei-yu rainfall in the YHRV and frequent occurrences of rainstorm processes.Moreover,two blocking highs were present in the middle to high latitudes over Eurasia,and a trough along the East Asian coast was also active,which allowed cold air intrusions to move southward through the northwestern and/or northeastern paths.The cold air frequently merged with the warm and moist air from the low latitudes resulting in low-level convergence over the YHRV.The persistent warming in the tropical Indian Ocean is found to be an important external contributor to an EAP/PJ-like teleconnection pattern over East Asia along with an intensified and southerly displaced WPSH,which was observed to be favorable for excessive rainfall over YHRV.

关键词： record-breaking mei-yu western Pacific subtropical high quasi-biweekly oscillation Tropical Indian Ocean warming low-level southwesterly jet blocking high

Causes and Predictability of the 2021 Spring Southwestern China Severe Drought

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Advances in Atmospheric Sciences 2022年第10期39卷 1766-1776页

作者： Yunyun Liu Zeng-Zhen HU Renguang WU Xing YUAN CMA Climate Studies Key Laboratory National Climate CenterChina Meteorological AdministrationBeijing 100081China Key Laboratory of Meteorological Disaster Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science&TechnologyNanjing 210044China Climate Prediction Center NCEP/NOAACollege ParkMaryland 20740USA School of Earth Sciences Zhejiang UniversityHangzhou 310058China School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China

In the spring of 2021,southwestern China(SWC)experienced extreme drought,accompanied by the highest seasonal-mean temperature record since 1961.This drought event occurred in the decaying phase of a La Niña event with negative geopotential height anomalies over the Philippine Sea,which is distinct from the historical perspective.Historically,spring drought over SWC is often linked to El Niño and strong western North Pacific subtropical high.Here,we show that the extreme drought in the spring of 2021 may be mainly driven by the atmospheric internal variability and amplified by the warming trend.Specifically,the evaporation increase due to the high temperature accounts for about 30%of drought severity,with the contributions of its linear trend portion being nearly 20%and the interannual variability portion being about 10%.Since the sea surface temperature forcing from the tropical central and eastern Pacific played a minor role in the occurrence of drought,it is a challenge for a climate model to capture the 2021 SWC drought beyond one-month lead times.

关键词： extreme spring drought Southwestern China precipitation evaporation warming trend internal variability predictability

Metal-free C(sp^(2))-H perfluoroalkylsulfonylation and configuration inversion:Stereoselective synthesis ofα-perfluoroalkylsulfonyl E-enaminones

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Chinese Chemical Letters 2021年第11期32卷 3514-3517页

作者： Qing Yu Yunyun Liu Jie-Ping Wan College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China

The perfluoroalkylsulfonylation(CF_(3)SO_(2),C_(2)F_(5)SO_(2)and CHF_(2)SO_(2))in the enaminone C-H bonds has been developed simply via the promotion of molecular iodine by using stable and cheap sodium perfluoroalkyl sulfinates as coupling partners.The stereoselective synthesis of E-configuratedα-perfluoroalkylsulfonyl enaminones has been realized via unprecedented C-H bond elaboration and C=C double bond configuration inversion by free radical process.

关键词： C-H Functionalization Enaminone Perfluoroalkyl sulfonylation Metal-free Configuration inversion

Microbiome research outlook:past,present,and future

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Protein & Cell 2023年第10期14卷 709-712页

作者： yunyun Gao Danyi Li Yong-Xin liu Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China R-Institute Co.Ltd. Beijing 100011China

With its critical role in human health and disease,the microbiome has transformed modern biology.Over the past few years,microbiome research has evolved rapidly,with microbiologists gradually shifting their focus from cataloging microorganisms in the human microbiome to understanding their functional roles and how they interact with the host.Here,we present the global trends in microbiome research and summarize the past and current work on microbiome published in Protein&Cell.

关键词： shifting transformed outlook

Evaluation of FY-3/VIRR Sea Surface Temperature Data for Climate Applications

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Journal of Meteorological Research 2021年第6期35卷 952-963页

作者： Yunyun Liu Sujuan WANG Jian liu Zhensong GONG Xiaolong JIA Laboratory of Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044 National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081 Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites National Satellite Meteorological CenterChina Meteorological AdministrationBeijing 100081

We evaluated the sea surface temperature(SST)products derived from the visible infrared radiometer on board the Fengyun-3 satellites(FY-3/VIRR)during 2016-2018 from the perspective of climate applications.The data had previously been reprocessed by the National Satellite Meteorological Center of China Meteorological Administration based on an updated SST retrieval algorithm.The overall consistency between the FY-3/VIRR SST data and the optimum interpolation SST version 2.1(OIv2.1)was better for monthly means than for pentad means,and showed a clear dependence on the season and location.There was better consistency in winter than in summer,and in the tropical central-eastern Pacific than in the western Pacific warm pool,tropical North Indian Ocean,and tropical Atlantic Ocean.The monthly deviation of the global average SST anomaly was-0.03±0.07℃ and the average root-meansquare errors(RMSEs)presented clear seasonal fluctuations with a maximum of approximately 0.5℃ in summer.The poor consistency of the FY-3/VIRR SST in summer may be partially attributed to the bias of the OIv2.1 data in global oceans(especially the Indian Ocean)as a result of the spatially heterogeneous in situ measurements from ships,buoys,and Argo floats.Convective activities and clouds in the tropics may also influence the accuracy of the FY-3/VIRR SST retrievals.The Nino SST indices based on both FY-3/VIRR and OIv2.1 SST data displayed a generally similar evolution,including the start and end of El Nino and La Nina events and their amplitudes,although the deviations were slightly larger when the Pacific SST anomaly was in the neutral state of the El Nino-Southern Oscillation(ENSO).The deviations varied greatly with season in the tropical Indian and Atlantic oceans,suggesting the need to perform further analyses and validation of the FY-3/VIRR SST products in these two basins.

关键词： visible infrared radiometer(VIRR) Fengyun-3 satellites(FY-3) sea surface temperature(SST) El Ni?o–Southern Oscillation(ENSO) evaluation climate application

Synthesis of Enaminone-Pd(Ⅱ)Complexes and Their Application in Catalysing Aqueous Suzuki-Miyaura Cross Coupling Reaction

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Chinese Journal of Chemistry 2020年第3期38卷 254-258页

作者： Leiqing Fu Xiaoji Cao Jie-Ping Wan Yunyun Liu College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchangJiangxi 330022China College of Chemistry and Bio-Engineering Yichun UniversityYichunJiangxi 336000China Research Centre for Measurement and Analysis Zhejiang University of TechnologyHangzhouZhejiang 310014China

A series of Pd(Ⅱ)-enaminone complexes,termed Pd(eao)2,have been synthesized and characterized.The investigation on the catalytic activities of these new Pd(Ⅱ)-reagents has proved that the Pd(ea0)2-1 possesses excellent catalytic activity for the Suzuki-Miyaura cross coupling reactions of aryl bromides/chlorides with ary/vinyl boronic acids in the environmentally benign media of aqueous PEG400 at low loading(5 mol‰).The superiority of this Pd(Ⅱ)-reagent to those commercial Pd(Ⅱ)and Pd(0)catalysts in catalyzing the reactions has been confirmed by parallel experiments.What's more,Pd(eao)2-2 has been found as a practical catalyst for the homo-coupling reactions of aryl boronic acids.

关键词： Suzuki Pd(Ⅱ) boron

Intracranial Epileptic Seizures Detection Based on an Optimized Neural Network Classifier

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Chinese Journal of Electronics 2021年第3期30卷 419-425页

作者： GONG Chen liu Jiahui NIU yunyun School of Information Engineering China University of Geosciences in Beijing Institute of Automation Chinese Academy of Sciences School of Artificial Intelligence University of Chinese Academy of Sciences

Automatic identification of intracranial electroencephalogram(i EEG) signals has become more and more important in the field of medical diagnostics.In this paper, an optimized neural network classifier is proposed based on an improved feature extraction method for the identification of i EEG epileptic seizures.Four kinds of entropy, Sample entropy, Approximate entropy, Shannon entropy, Log energy entropy are extracted from the database as the feature vectors of Neural network(NN) during the identification process.Four kinds of classification tasks, namely Pre-ictal v Post-ictal(CD), Pre-ictal v Epileptic(CE), Post-ictal v Epileptic(DE), Pre-ictal v Post-ictal v Epileptic(CDE),are used to test the effect of our classification method.The experimental results show that our algorithm achieves higher performance in all tasks than previous algorithms.The effect of hidden layer nodes number is investigated by a constructive approach named growth method. We obtain the optimized number ranges of hidden layer nodes for the binary classification problems CD, CE, DE, and the multitask classification problem CDE, respectively.

关键词： Electrical activity in neurophysiological processes Signal detection Bioelectric signals Digital signal processing Electrodiagnostics and other electrical measurement techniques Biology and medical computing iEEG Neural network (NN) Entropy Feature extraction Mutual range of coefficient Hidden layer node.

Copper-Catalyzed Hydrosulfonylation of Alkynes Employing Sulfonohydrazides toward the Synthesis of Vinyl Sulfones

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Chinese Journal of Chemistry 2016年第10期34卷 1053-1057页

作者： Deqing Hu Feicheng Bai Yunyun Liu Jie-Ping Wan College of Chemistry and Chemical Engineering Jiangxi Normal University Nanchang Jiangxi 330022 China

The hydrosulfonylation of terminal alkynes employing sulfonohydrazides has been accomplished with cop- per-catalysis in the presence of BPO （benzoic peroxyanhydride）. Generally, excellent yield of the vinyl sulfone ... 详细信息

关键词： alkyne sulfonohydrazide hydrosulfonylation copper catalysis E-selectivity