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Synthesis of a glucose conjugate of pristimerin and evaluation of its anticancer activity

Chinese Chemical Letters 2023年第1期34卷 310-312页

作者： Fan Yang jie Zhang jiacheng Li Wenbo Ye ang Li Weiwei He Shanghai Key Laboratory of New Drug Design School of PharmacyEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Bioorganic and Natural Product Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China The Research Center of Chiral Drugs Innovation Research Institute of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai 201203China

Taking advantage of the Warburg effect in cancer cells, glucose conjugation has emerged as a useful strategy for targeted delivery of anticancer agents. Pristimerin is a naturally occurring triterpenoid that displays potent but non-selective cytotoxicity. We developed a convergent and modular approach to construction of glucose-payload conjugates featuring copper-mediated azide-alkyne cycloaddition and prepared a glucose conjugate of pristimerin through this approach. The anticancer activity of this conjugate was evaluated in cancer cells and normal cells;however, the selectivity toward cancer cells was not significantly improved. We then examined the extracellular stability of the conjugate and found that its ester linkage was cleaved rapidly in Dulbecco’s Modified Eagle’s Medium at 37 °C, which resulted in the release of pristimerin. In fact, the inorganic components in this medium were sufficient to induce the *** that the subtle difference between intrinsic stability and extracellular stability of the conjugate linker is often underappreciated, this work highlights the importance of the latter in the development of target-selective conjugates.

关键词： Glucose conjugation Warburg effect Pristimerin Extracellular stability

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Parallel implementation of w-projection wide-field imaging

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Science Bulletin 2019年第9期64卷 586-594页

作者： Baoqiang Lao Tao An ang Yu Wenhui Zhang junyi Wang Quan Guo Shaoguang Guo Xiaocong Wu Shanghai Astronomical Observatory Key Laboratory of Radio AstronomyChinese Academy of Sciences Guangxi Cooperative Innovation Center of Cloud Computing and Big Data Guilin University of Electronic Technology Guangxi Colleges and Universities Key Laboratory of Cloud Computing and Complex Systems Guilin University of Electronic Technology

w-Projection is a wide-field imaging technique that is widely used in radio synthesis arrays. Processing the wide-field big data generated by the future Square Kilometre Array(SKA) will require significant updates to current methods to significantly reduce the time consumed on data processing. Data loading and gridding are found to be two major time-consuming tasks in w-projection. In this paper, we investigate two parallel methods of accelerating w-projection processing on multiple nodes: the hybrid Message Passing Interface(MPI) and Open Multi-Processing(OpenMP) method based on multicore Central Processing Units(CPUs) and the hybrid MPI and Compute Unified Device Architecture(CUDA)method based on Graphics Processing Units(GPUs). Both methods are successfully employed and operated in various computational environments, confirming their robustness. The experimental results show that the total runtime of both MPI + OpenMP and MPI + CUDA methods is significantly shorter than that of single-thread processing. MPI + CUDA generally shows faster performance when running on multiple nodes than MPI + OpenMP, especially on large numbers of nodes. The single-precision GPU-based processing yields faster computation than the double-precision processing; while the single-and doubleprecision CPU-based processing shows consistent computational performance. The gridding time remarkably increases when the support size of the convolution kernel is larger than 8 and the image size is larger than 2,048 pixels. The present research offers useful guidance for developing SKA imaging pipelines.

关键词： Radio synthesis arrays Square kilometre array Wide field imaging Parallelization w-Projection

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Observation on the aerosol and ozone precursors in suburban areas of Shenzhen and analysis of potential source based on MAX-DOAS

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journal of Environmental Sciences 2023年第10期132卷 109-121页

作者： Hairong Zhang ang Li Zhaokun Hu Hongmei Ren Hongyan Zhong jianfeng Guo Long Yun Mingdi Zhang Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China Shenzhen Environmental Monitoring Center Station Shenzhen 518049China

Long-term stereoscopic observations of aerosol,NO2,and HCHO were carried out at the Yangmeikeng(YMK)site in *** optical depths and NO2 vertical column concentration(NO2 VCD)derived from MAX-DOAS were found to be consistent with other *** total NO2 VCD values of the site remained low,varying from 2×10^(15)to 8×10^(15)mol/cm^(2),while the HCHO VCD was higher than NO2 VCD,varying from 7×10^(15)to 11×10^(15)mol/cm^(2).HCHO VCD was higher from September to early November than that was from mid-late November to December and during February 2021,in contrast,NO2 VCD did not change much during the same *** january,NO2 VCD and HCHO VCD were both fluctuating *** temperature and HCHO level in the YMK site is not only driving the ozone production up but alsomay be driving up the ozone concentration as well,and the O_(3)production regime in the YMK site tends to be *** various altitudes,backward trajectory clustering analysis and Potential Source Contribution Function(PSCF)were utilized to identify possible NO2 and HCHO source *** results suggested that the Huizhou-Shanwei border and the Daya Bay Sea area were the key potential source locations in the lower(200 m)and middle(500 m)atmosphere(WPSCF>0.6).The WPSCF valuewas high at the 1000maltitude whichwas closer to the YMKsite than the near ground,indicating that the pollution transport capability in the upper atmosphere was limited.

关键词： Multi-axial differential optical absorption spectroscopy (MAX-DOAS) Nitrogen dioxide(NO2) Formaldehyde(HCHO) Potential source contribution function(PSCF)

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Influence of precipitation on bacterial structure in a typical karst spring,SW China

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journal of Groundwater Science and Engineering 2018年第3期6卷 193-204页

作者： SONG ang LIang Yue-ming LI Qiang Key Laboratory of Karst Dynamics MLR and GuangxiInstitute of Karst GeologyChinese Academy of Geological SciencesGuilin 541004China International Research Center on Karst under the Auspices of UNESCO Guilin 541004China

Micro-organisms are major components in the environment, which play a key role in groundwater environment. This study aims to investigate the bacterial diversity over time in a typical karst spring named S31 and its response to hydrogeochemical parameters. Quantitative PCR and 16S rRNA high-throughput sequencing was adopted to detect changes of the bacterial community structure. For the correlations between hydrogeochemical parameters and predominant phyla, redundancy analysis were adopted. According to the results, hydrochemical characteristics were controlled by carbonate equilibrium system and dynamic groundwater transformation which was influenced distinctly by precipitation. In addition, the redundancy analysis indicates that HCO_3^-, Ca^(2+), Eh, temperature and cumulative precipitation are the most important hydrogeochemical and environmental parameters to determine the bacterial community structures. That is to say, temperature can influence bacterial abundance by controlling dissolved oxygen content. Precipitation is another important factor which determines the community composition and bacterial structure directly or indirectly. Moreover, acidobacteria, proteobacteria, and bacteroidetes play key roles in response to the environmental factors in the groundwater of karst zones.

关键词： Karst spring Precipitation Bacterial diversity 16S rRNA Illumina sequencing

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Study of aerosol characteristics and sources using MAX-DOAS measurement during haze at an urban site in the Fenwei Plain

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journal of Environmental Sciences 2021年第9期33卷 1-13页

作者： Xiaomei Li Pinhua Xie ang Li jin Xu Hongmei Ren Bo Ren Yanyu Li jie Li Key laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China CAS Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Institute of Atmospheric Physics Chinese Academy of ScienceBeijing 100029China

Atmospheric aerosols have effects on atmospheric radiation assessments,global climate change,local air quality and *** particular,aerosols are more likely transformed and accumulated in *** this paper,we used the Multi-Axis Differential Optical Absorption Spectroscopy(MAX-DOAS)instrument to study the characteristics of aerosol type and contributions of PM_(2.5) chemical components to aerosol extinction(AE),vertical distribution of aerosols,and *** December 30,2018 to january 27,2019,we conducted MAX-DOAS observations on *** proportion of PM_(2.5) to PM10 was 69.48%-95.39%,indicating that the aerosol particles were mainly fine *** analyzing the ion data and modifying Interagency Monitoring of Protected Visual Environments(IMPROVE)method,we found that nitrate was the largest contributor to AE,accounting for 31.51%,28.98%,and 27.95%of AE on heavily polluted,polluted,and clean days,***4+,OC,and SO42-were also major contributors to *** near-surface aerosol extinction retrieved from MAX-DOAS measurement the PM_(2.5) and PM10 concentrations measured by an Unmanned Aerial Vehicle(UAV)have the same trend in vertical *** increased about 3 times from surface to 500 *** the backward trajectory of the air mass during the haze,we also found that the continuous heavy pollution was mainly caused by transport of polluted air from the northeast,then followed by local industrial emissions and other sources of emissions under continuous and steady weather conditions.

关键词： MAX-DOAS Aerosol optical depth(AOD) Aerosol extinction(AE) Haze PM_(2.5) IMPROVE

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Annealing engineering induced high thermoelectric performance in Yb-filled CoSb_(3) skutterudites

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journal of Materials Science & Technology 2023年第19期150卷 168-174页

作者： Haoran Feng Qian Deng Yan Zhong Xuri Rao Yadong Wang j.anglong Zhu Fujie Zhang Ran ang Key Laboratory of Radiation Physics and Technology Ministry of EducationInstitute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China Institute of New Energy and Low-Carbon Technology Sichuan UniversityChengdu 610065China

The great pressure of energy shortage has made CoSb_(3) materials with excellent mechanical stability in the mid-temperature region favored for the integration of thermoelectric ***,their ex-cessive lattice thermal conductivity and poor Seebeck coefficient lead to low energy conversion *** Yb into the lattice void to optimize the band structure and regulate the chemical po-tential is an indispensable means for improving the thermoelectric properties of CoSb_(3)-based materials,while the phase structure and thermoelectric properties vary with the preparation *** motivates the current work to focus on the influence of annealing temperature on the microstructure and thermoelectric properties of Yb-filled CoSb_(3).Experimental analysis and theoretical model eluci-dated that an increase in annealing temperature can optimize the Yb filling fraction,which simulta-neously manipulates the band structure as well as chemical potential,resulting in an excellent electrical ***,the phase and microstructure characterization clarify that the annealing temperature can effectively affect the grain *** complex grain boundary induced by grain refinement,more filled Yb atoms and precipitates strongly scatter wide-frequency phonons,significantly suppressing the lattice thermal *** a result,a superior dimensionless figure of merit(ZT)value of~1.33 at 823 K and an average ZTave of~0.9(323-823 K)were achieved in the Ybo.4Co4Sb12 sample annealed at 923 K,and the calculated conversion efficiency could reach~13%.This work pro-vides a unique paradigm to improve thermoelectrics in the filled CoSb_(3)-based skutterudites by annealing engineering.

关键词： CoSb_(3)skutterudite Annealing engineering Grain refinement Phonon scattering Thermoelectric optimization

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Characteristics and outcomes of out-of-hospital cardiac arrest in Zhej.ang Province

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World journal of Emergency Medicine 2018年第2期9卷 141-143页

作者： Min Fei Wen-wei Cai Sheng-ang Zhou Department of Emergency Medicine Zhejiang Provincial People's Hospital

China has undergone tremendous economic growth,but there still remains much room for improvement inemergency medical service （EMS） system.[1] The EMSin China comprises of three parts： the pre-hospitalemergency service, the emergency department, andthe intensive care unit. Not much is known about theexact numbers of out-of-hospital cardiac arrest （OHCA）across the whole of China, though there are reports fromspecifi c provinces.

关键词： Characteristics outcomes of out-of-hospital cardiac arrest Zhej.ang Province

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长运距带式输送机动态启动特性的研究

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煤矿机械 2025年第1期46卷 80-82页

作者：楚金龙王伟京胡长对曹树昂平煤神马机械装备集团有限公司河南平顶山467021

以某煤矿主斜井下段带式输送机为研究对象,基于AMESim软件对长运距带式输送机系统的启动特性进行动态仿真分析。阐述了启动过程中输送带张力的动态变化规律,并与理论计算结果进行对比。同时分析了不同启动时间、加速度曲线下的动态响应... 详细信息

以某煤矿主斜井下段带式输送机为研究对象,基于AMESim软件对长运距带式输送机系统的启动特性进行动态仿真分析。阐述了启动过程中输送带张力的动态变化规律,并与理论计算结果进行对比。同时分析了不同启动时间、加速度曲线下的动态响应,为系统的启动参数设置提供指导与建议。

关键词：长运距带式输送机动态启动仿真分析 AMESim

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Heuristic multistep attack scenarios construction based on kill chain

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The journal of China Universities of Posts and Telecommunications 2023年第5期30卷 61-71页

作者： Cheng jie Zhang Ru Wei jiahui Lu Chen Lü Zhishuai Lin Bingjie Xia ang State Grid Information and Telecommunication Branch Beijing 100761China School of Cyberspace Security Beijing University of Posts and TelecommunicationsBeijing 100876China

Network attacks evolved from single-step and simple attacks to complex multistep *** methods of multistep attack detection usually match multistep attacks from intrusion detection systems(IDS)alarms based on the correlation between attack ***,IDS has false negatives and false positives,which leads to incomplete or incorrect multistep *** based on simple similarity is difficult to obtain an accurate attack cluster,while association based on prior knowledge such as attack graphs is difficult to guarantee a complete attack knowledge *** solve the above problems,a heuristic multistep attack scenarios construction method based on the kill chain(HMASCKC)model was *** attack model graph can be obtained from dual data sources and heuristic multistep attack scenarios can be obtained through graph *** model graph of the attack and the predicted value of the next attack are obtained by calculating the matching *** according to the purpose of the multistep attack,the kill chain model is used to define the initial multistep attack model,which is used as the initial graph for graph *** results show that HMASCKC model can better fit the multistep attack behavior,the effect has some advantages over the longest common subsequence(LCS)algorithm,which can close to or match the prediction error of judge evaluation of attack intension(jEAN)*** method can make multistep attack model matching for unknown attacks,so it has some advantages in practical application.

关键词： multistep attack scenario kill chain graph matching attack prediction

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Construction of alkyl-substituted 7-norbornenones through Diels-Alder cycloaddition of electron-deficient olefins and a cyclopentadienone derivative generated in situ

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Chinese Chemical Letters 2022年第4期33卷 2041-2043页

作者： Shanxiang Liu jinxin Wang Yuyong Ma Xin Cao Wei-Dong Zhang ang Li School of Traditional Chinese Pharmacy China Pharmaceutical UniversityNanjing 211198China State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 200032China State Key Laboratory of Innovative Natural Medicine and Traditional Chinese Medicine Injections Jiangxi Qingfeng Pharmaceutical Co.Ltd.Ganzhou 341000China Department of Phytochemistry School of PharmacySecond Military Medical UniversityShanghai 200433China

Dimeric sesquiterpenoids possessing densely substituted 7-norbornenone/7-norbornenol motifs pose a considerable challenge for chemical synthesis. From a strategic perspective, one could envision intermolecular Diels-Alder cycloaddition as a straightforward method for assembling alkyl-substituted 7-norbornenones. However, this approach is hindered by lability of the required dienes, namely alkylsubstituted cyclopentadienones. Here we report a one-pot protocol for construction of alkyl-substituted7-norbornenones from electron-deficient olefins and a cyclopentenone derivative. DDQ was found to be an effective oxidant for generating a cyclopentadienone intermediate in situ from the enone. A series of sterically congested 7-norbornenone-containing polycyclic compounds were prepared by using this protocol.

关键词： 7-Norbornenone Alkyl-substituted cyclopentadienone Diels-Alder cycloaddition Dimeric sesquiterpenoid

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