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Synthesis of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives

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Chinese Chemical Letters 2007年第4期18卷 380-382页

作者： xue fei Yang Ling Yi Kong Department of Natural Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

A series of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives have been synthesized by utilizing the coupling of methyl 3- methoxy-4hydroxy-5-bromocinnamate with cuprous phenylacetylide as the key step. The structures of the new compounds were confirmed by 1H NMR, IR and MS. The structure of compound 14 was further confirmed by single crystal X-ray. Compound 17 showed cytotoxic activity against human lung carcinoma A549.

关键词： 2-Aryl-5-alkyl-7-methoxylbenzo[b]furan Neolignans Synthesis Cytotoxicity

A new chronic ulcerative colitis model produced by combined methods in rats

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World Journal of Gastroenterology 2000年第5期6卷 742-746页

作者： xue Liang Jiang Hui fei Cui Department of Gastroenterology Chinese PLA General Hospital of Jinan CommandJinan 25003lChina Department of Biochemical Pharrnaceutics Shandong Medical UniversityJinan 250012Shandong ProvinceChina

INTRODUCTIONThe etiopathogenesis of ulcerative colitis (UC)remains obscure,due to lack of an ideal *** thc improvement of theory andmethodology in the last 30 years,people used toadopt chemicals(acetic acid,ethanol,carrageen,etc.),immunotechniques(humoral or cellularimmunity,immune complex) and substance derivedfrom UC patients to set up various kinds of UCanimal model,which mimic the pathologic changesof human UC,so far these remain far

关键词： colitis ulcerative animal model 2,4-dinitrochlorobenzene acetic acids apoptosis flow cytometry intestinal mucosa/pathology

Improving Thermal-oxidative Aging Resistance of Styrene-butadiene Rubber by Antioxidant Loaded Silica Aerogel

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Chinese Journal of Polymer Science 2024年第8期42卷 1198-1209页

作者： xue-fei Ping Yu Wang Lu Liu Fu-Yong Liu Hong-Wei He Pi Wang Wen-Wen Yu Qiang zheng College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030032China Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China

The antioxidant N-isopropyl-N'-phenyl-p-phenylenediamine(4010NA)was dissolved in ethanol and impregnated into silica aerogel(SAG)via vacuum-pressure cycles,yielding composite particles(A-N)with enhanced sustained-release and reinforcing *** effect of A-N on the mechanical properties and thermal-oxidative aging resistance of styrene-butadiene rubber(SBR)vulcanizates was *** and BET assessments indicated that the loading efficiency of 4010NA in SAG reached 14.26%within ethanol's solu bility *** A-N into SBR vulcanizates significantly elevated tensile strength by 17.5%and elongation at break by 41.9%over those with fumed silica and ***,A-N notably enhanced the thermal-oxidative aging resistance of *** aging for 96 h at 100℃,the tensile strength and elongation at break of SBR with A-N sustained 70.09%and 58.61%of their initial values,respectively,with the retention rate of elongation at break being 62.8%higher than that of SBR with fumed silica and free *** study revealed that A-N composite particles significantly inhibited the crosslinking in SBR's molecular chains,reducing hardening and embrittlement during later thermal-oxidative aging stages.

关键词： Styrene-butadiene rubber Silica aerogel Loading modification Thermal-oxidative aging

ENSO Variability Simulated by a Coupled General Circulation Model:ECHAM5/MPI-OM

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Atmospheric and Oceanic Science Letters 2014年第5期7卷 471-475页

作者： zheng fei International Center for Climate and Environment Science (ICCES) Institute of Atmospheric Physics Chinese Academy of Sciences

The accurate simulation of the equatorial sea surlhce temperature （SST） variability is crucial for a proper representation or prediction of the El Nino-Southern Os- cillation （ENSO）. This paper describes the tropical variability simulated by the Max Planck Institute （MPI） forr meteorology coupled atmosphere-ocean general circulation model （CGCM）. A control simulation with pre-industrial greenhouse gases is analyzed, and the simulation of key oceanic features, such as SST, is compared with observa- tions. Results from the 400-yr control simulation show that the model＇s ENSO variability is quite realistic in terms of structure, strength, and period. Also, two related features （the annual cycle of SST and the-phase locking of ENSO events）, which are significant in determining the model＇s performance of realistic ENSO prediction, are further validated to be well reproduced by the MPI cli mate model, which is an atmospheric model ECHAM5 （which fuses the EC tbr European Center and HAM for Hamburg） coupled to an MPI ocean model （MPI-OM）, ECHAMS/MPI-OM.

关键词： ENSO variability CGCM ECHAM5/MPI-OM

Diversity and functional analysis of Chinese bumblebee gut microbiota reveal the metabolic niche and antibiotic resistance variation of Gilliamella

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Insect Science 2021年第2期28卷 302-314页

作者： Zi-Jing Zhang Ming-fei Huang Li-fei Qiu Rui-Hao Song Zi-Xuan Zhang Yi-Wen Ding Xin Zhou xue Zhang Hao zheng College of Food Science and Nutritional Engineering China Agricultural UniversityBeijingChina College of Plant Protection China Agricultural UniversityBeijingChina

Bumblebees play an important role in maintaining the balance of natural and agricultural ecosystems,and the characteristic gut microbiota of bumblebees exhibit significant mutualistic *** has the highest diversity of bumblebees;however,gut microbiota of Chinese bumblebees have mostly been investigated through cultureindependent ***,we analyzed the gut communities of bumblebees from Sichuan,Yunnan,and Shaanxi provinces in China through 16S ribosomal RNA amplicon sequencing and bacterial *** revealed that the bumblebees examined in this study harbored two gut enterotypes as previously reported:one is dominated by Gilliamella and Snodgrassella,and the other is distinguished by prevalent environmental *** gut compositions obviously varied among different individual *** then isolated 325 bacterial strains and the comparative genomic analysis of Gillianiella strains revealed that galactose and pectin digestion pathways were conserved in strains from bumblebees,while genes for the utilization of arabinose,mannose,xylose,and rhamnose were mostly *** two strains from the Chinese bumblebees possess the multidrug-resistant gene emrB,which is phylogenetically closely related to that from the symbionts of soil entomopathogenic *** contrast,tetracycline-resistant genes were uniquely present in three strains from the *** results illustrate the prevalence of strain-level variations in the metabolic potentials and the distributions of antibiotic-resistant genes in Chinese bumblebee gut bacteria.

关键词： antibiotic resistance bumblebee Gilliamella.,gut microbiota sugar metabolism

Effects of interannual salinity variability on the dynamic height in the western equatorial Pacific as diagnosed by Argo

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Acta Oceanologica Sinica 2015年第5期34卷 22-28页

作者： zheng fei WANG Hui WAN Liying International Center for Climate and Environment Science (ICCES) Institute of Atmospheric PhysicsChinese Academy of Sciences National Meteorological Center Key Laboratory of Research on Marine Hazards Forecasting National Marine Environmental Forecasting Center

In this paper, interannual variations of the ocean dynamic height over the tropical Pacific are diagnosed using three-dimensional temperature and salinity fields from Argo profiles, with a focus on the effects of interannually varying salinity on the El Nino-Southern Oscillation （ENSO） evolutions. The diagnostic analyses clearly demonstrate a significant and large role that the salinity field plays in modulating the sea surface dynamic height （SSDH） in the western tropical Pacific. In particular, the contribution of the interannually varying salinity to the interannual variations in SSDH approximately equals to that of the interannually varying temperature. Over the western equatorial Pacific, the salinity variability was responsible for a 30% to 40% reduction in SSDH anomaly in opposition to the thermal build up in SSDH anomaly, providing an important contribution to modulating the seasonal-to-interannual evolution of the tropical Pacific Ocean and affecting the developing of ENSO events.

关键词： salinity effect SSDH ENSO Argo western tropical Pacific

ENSO Frequency Asymmetry and the Pacific Decadal Oscillation in Observations and 19 CMIP5 Models

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Advances in Atmospheric Sciences 2018年第5期35卷 495-506页

作者： Renping LIN fei zheng Xiao DONG International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology

Using observational data and the pre-industrial simulations of 19 models from the Coupled Model Intercomparison Project Phase 5（CMIP5）, the El Ni o（EN） and La Ni a（LN） events in positive and negative Pacific Decadal Oscillation（PDO） phases are examined. In the observational data, with EN（LN） events the positive（negative） SST anomaly in the equatorial eastern Pacific is much stronger in positive（negative） PDO phases than in negative（positive） phases. Meanwhile,the models cannot reasonably reproduce this difference. Besides, the modulation of ENSO frequency asymmetry by the PDO is explored. Results show that, in the observational data, EN is 300% more（58% less） frequent than LN in positive（negative）PDO phases, which is significant at the 99% confidence level using the Monte Carlo test. Most of the CMIP5 models exhibit results that are consistent with the observational data.

关键词： ENSO frequency asymmetry Pacific Decadal Oscillation decadal variation Monte Carlo method CM1P5

建设健康社会的催化剂:健康社会工作者与全科医生在基层的合作

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中国全科医学 2025年第4期28卷 516-520页

作者：李奕桦赵艾杨曾飞方雪张旺王欣武汉大学中南医院创伤与显微骨科湖北省武汉市430071 巴东县人民医院骨科湖北省恩施土家族苗族自治州444300

以“健康中国”战略为导向,从优势互补专业知识、共同连接医院社区、拓展研究社会健康三个方面去探讨健康社会工作者与全科医生在基层卫生环境中的合作价值,尤其在完善公共卫生应急体系和构建医联体上,健康社会工作者与全科医生的合作... 详细信息

以“健康中国”战略为导向,从优势互补专业知识、共同连接医院社区、拓展研究社会健康三个方面去探讨健康社会工作者与全科医生在基层卫生环境中的合作价值,尤其在完善公共卫生应急体系和构建医联体上,健康社会工作者与全科医生的合作可以发挥必不可少的作用,能有效推动健康社会的建设进程。同时文章也指明了目前健康社会工作面临的主要挑战,并提出相应的对策。

关键词：健康社会健康社会工作者全科医生基层卫生公共卫生应急医联体

Analysis of Galileo signal-in-space range error and positioning performance during 2015-2018

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Satellite Navigation 2020年第1期1卷 55-67页

作者： Weiwang Wu fei Guo Jiazhu zheng School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan 430079China College of Civil Engineering Nanjing Forestry University159 Lonpan RoadNanjing 210037China

A long-term analysis of signal-in-space range error (SISRE) is presented for all healthy Galileo satellites, and the first pair of full operational capability satellites in wrong elliptical orbits. Both orbit and clock errors for Galileo show an obvious convergence trend over time. The annual statistical analyses show that the average root mean squares (RMSs) of SISRE for the Galileo constellation are 0.58 m (2015), 0.29 m (2016), 0.23 m (2017), and 0.22 m (2018). Currently, the accuracy of the Galileo signal-in-space is superior to that of the global positioning system (GPS) Block IIF (0.35 m). In addition, the orbit error accounts for the majority of Galileo SISRE, while the clock error accounts for approximately one-third of SISRE due to the high stability of the onboard atomic clock. Single point positioning results show that Galileo achieves an accuracy of 2-3 m, which is comparable to that of GPS despite the smaller number of satellites and worse geometry. Interestingly, the vertical accuracy of Galileo, which uses the NeQuick ionospheric model, is higher than that of GPS. Positioning with single frequency E1 and E5 show a higher precision than E5a and E5b signals. Regarding precise point positioning (PPP), the results indicate that a comparable positioning accuracy can be achieved among different stations with the current Galileo constellation. For static PPP, the RMS values of Galileo-only solutions are within 1 cm horizontally, and the vertical RMSs are mostly within 2 cm horizontally. For kinematic PPP, the RMSs of Galileo-only solutions are mostly within 4 cm horizontally and 6 cm vertically.

关键词： Galileo Signal in space range error(SISRE) Single point positioning(SPP) Precise point positioning(PPP)