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In vitro Potentiation of Antimalarial Activities by Daphnetin Derivatives Against Plasmodium falciparum

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Biomedical and Environmental Sciences 2006年第5期19卷 367-370页

作者： FANG HUANG lin-HUA TANG lin-qian yu YI-CHANG NI QIN-MEI WANG FA-JUN NAN National Institute of Parasite Diseases Chinese Center for Disease Control and Prevention Shanghai 200025 China Chinese National Center for Drug Screening Shanghai Institute of Materia Medica Shanghai Institute for Biological Sciences Graduate School of the Chinese Academy of Sciences Shanghai 201203 China

Objective To screen the antimalarial compounds of daphnetin derivatives against Plasmodium falciparum in vitro. Method Plasmodium faciparum （FCC1） was cultured in vitro by a modified method of Trager and Jensen. Antimalarial compounds were screened by microscopy-based assay and microfluorimetric method. Results DA79 and DA78 showed potent antimalarial activity against Plasmodiumfalciparum cultured in vitro. Conclusion Though the relationship between the structures of daphnetin derivatives and their antimalarial activities has not been clarified yet, this study may provide a new direction for discovery of more potential antimalarial compounds.

关键词： Daphnetin Antimalarial Drug screening

Joined AZ31B Magnesium Alloys with Ag Interlayer by Ultrasonic-Induced Transient Liquid Phase Bonding in Air

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1177-1185页

作者： qian Wang Peng yu Haoran lin Chongzhi Guo Xiaoqiang Hu Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China School of Rare Earths University of Science and Technology of ChinaHefei230026China Shenyang 7D New Materials Equipment Co.LTD. Shenyang110076China Shenyang National Laboratory of Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

AZ31B magnesium alloys are commonly used in lightweight structures of automobile and aerospace *** this work,the ultrasonic-induced transient liquid phase bonding technique is deployed to joint AZ31B magnesium alloys at 490℃ with Ag interlayer in the *** effect of ultrasonic vibration on microstructure and mechanical properties of welding seam is *** vibration duration increases,the width of the welding seam increases firstly and then *** the ultrasound vibration sustained for one second,the eutectic reaction occurred in the contacting interface between Ag interlayer and the base metal AZ31B,resulting in formation of liquid phase and metallurgical *** the ultrasound vibration sustained for seven second,the width of the welding seam increased to a maximum of about 303.1μm and the average shear bond strength of the welding joint attained the peak value of about 66.87 *** the ultrasound vibration sustained over seven seconds,the liquid phase is gradually squeezed out and the width of the welding seam decreases.α-Mg and AgMg_(3) can be observed in the welding *** analysis shows thatα-Mg has a certain strengthening *** whole process of appearance,growth and integration ofα-Mg is analyzed.

关键词： Ultrasonic bonding Magnesium alloy Silver Microstructure Intermetallic compound

Toward a rapid and convenient nanoplastic quantification method in laboratory-scale study based on fluorescence intensity

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 117-126页

作者： Ruiqi Yan Sen lin qian Ding Lei Zhang Xia yu Wentao Zhao qian Sui State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process School of Resources and Environmental EngineeringEast China University of Science and TechnologyShanghai200237China State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai200092China

The thorough investigation of nanoplastics(NPs)in aqueous environments requires efficient and expeditious quantitative analytical methods that are sensitive to environmentally relevant NP concentrations and convenient to *** analysis-based quantitative methods have been acknowledged as effective and rapid approaches for quantifying NP concentrations in laboratory-scale ***,we compared three commonly used optical response indicators,namely fluorescence intensity(FI),ultraviolet absorbance,and turbidity,to assess their performance in quantifying ***,orthogonal experiments were conducted to evaluate the influence of various water quality parameters on the preferred indicator-based quantification *** results revealed that FI exhibits the highest correlation coefficient(>0.99)with NP ***,the limit of quantification(LOQ)for various types of NPs is exceptionally low,ranging from 0.0089 to 0.0584 mg/L in ultrapure water,well below environmentally relevant *** variations in water quality parameters such as pH,salinity,suspended solids(SS),and humic acid,a robust relationship between detectable FI and NP concentration was ***,an increased matrix,especially SS in water samples,results in an enhanced LOQ for ***,the quantitative method remains applicable in real water bodies,especially in drinking water,with NP LOQ as low as 0.0157–0.0711 mg/*** exceeds the previously reported detectable concentration for 100 nm NPs at 40µg/mL using surface-enhanced Raman *** study confirms the potential of FI as a reliable indicator for the rapid quantification of NPs in aqueous environments,offering substantial advantages in terms of both convenience and cost-effectiveness.

关键词： Nanoplastic quantification Fluorescence intensity Drinking water Limit of quantification(LOQ) Matrix effects

Hydrothermal synthesis of xonotlite from carbide slag

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Progress in Natural Science:Materials International 2008年第9期18卷 1147-1153页

作者： Jianxin Cao , Fei Liu, qian lin, yu Zhang Department of Chemical Engineering, Guizhou University, Guiyang 550003, China Department of Chemical Engineering Guizhou University Guiyang 550003 China

Carbide slag was used as the calcareous materials for the first time to prepare xonotlite via dynamic hydrothermal *** efiects of infiuential factors including difierent calcination temperatures, pretreatment methods of the carbide slag and process param-eters of hydrothermal synthesis on the microstructure and morphology of xonotlite were explored using XRD and SEM *** results indicate that the carbide slag after proper calcination could be used to prepare pure xonotlite;and difierent calcination tem-peratures have little efiect on the crystallinity of synthesized xonotlite, but have great impact on the morphology of secondary *** difierent pretreatment methods of the carbide slag pose great impact on the crystallinity and morphology of secondary particles of *** was also synthesized from pure CaO under the same experimental conditions as that prepared from calcined carbide slag for *** amount of impurities in carbide slag has no efiect on the mechanism of hydrothermal synthesizing xonotlite from carbide slag.

关键词： Hydrothermal synthesis Carbide slag Xonotlite Calcination temperature

Biomass derived Fe-N/C catalyst for efficiently catalyzing oxygen reduction reaction in both alkaline and neutral pH conditions

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Chinese Chemical Letters 2023年第1期34卷 465-468页

作者： lin-qian yu Hao Wang Shu-La Chen Te-Er Wen Bao-Cheng Huang Ren-Cun Jin Laboratory of Water Pollution Remediation School of Life and Environmental SciencesHangzhou Normal UniversityHangzhou 311121China

Fe-N/C is a promising oxygen reduction reaction(ORR)catalyst to substitute the current widely used precious metal ***-effectively fabricating the Fe-N/C material with high catalytic activity and getting in-depth insight into the responsible catalytic site are of great *** this work,we proposed to use biomass,tea leaves waste,as the precursor to prepare ORR *** adding 5%FeCl3(wt%)into tea precursor,the pyrolysis product(i.e.,5%Fe-N/C)exhibited an excellent four-electron ORR activity,whose onset potential was only 10 m V lower than that of commercial Pt/*** limiting current density of 5%Fe-N/C(5.75 m A/cm^(2))was even higher than Pt/C(5.44 m A/cm^(2)).Compared with other biomass or metal organic frameworks derived catalysts,5%Fe-N/C showed similar ORR ***,both the methanol tolerance and material stability performances of as-prepared 5%Fe-N/C catalyst were superior to that of Pt/C.X-ray adsorption fine structure characterization revealed that the FeN4O2might be the possible catalytic *** appropriate amount of iron chloride addition not only facilitated catalytic site formation,but also enhanced material conductivity and reaction *** results of this work may be useful for the Fe based transition metal ORR catalyst design and application.

关键词： Fe-N/C Oxygen reduction reaction Biomass Fe coordination Polyphenol

Characteristics of the HIV/AIDS Epidemic among People Aged≥50 Years in China during 2018–2021

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Biomedical and Environmental Sciences 2024年第4期37卷 399-405页

作者： HOU yu Shan JIN Yi Chen CAI Chang TANG Hou lin QIN qian qian Lyu Fan National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China

Objective This study aimed to determine the current epidemiological status of PLWHA aged≥50 years in China from 2018 to *** also aimed to recommend targeted interventions for the prevention and treatment of HIV/AIDS in elderly *** Data on newly reported cases of PLWHA,aged≥50 years in China from 2018 to 2021,were collected using the *** tests and spatial analyses were also *** Between 2018 and 2021,237,724 HIV/AIDS cases were reported among patients aged≥50 years in *** main transmission route was heterosexual transmission(91.24%).Commercial heterosexual transmission(CHC)was the primary mode of transmission among males,while non-marital non-CHC([NMNCHC];60.59%)was the prevalent route in *** proportion of patients with CHC decreased over time(Z=67.716,P<0.01),while that of patients with NMNCHC increased(Z=153.05,P<0.01).The sex ratio varied among the different modes of infection,and it peaked at 17.65 for *** spatial analysis indicated spatial clustering,and the high-high clustering areas were mainly distributed in the southwestern and central-southern *** In China,PLWHA,aged≥50 years,were predominantly infected through heterosexual *** primary modes of infection were CHC and *** were variations in the sex ratio among different age groups,infected through various sexual ***/AIDS cases exhibited spatial *** on these results,the expansion of HIV testing,treatment,and integrated behavioral interventions in high-risk populations is recommended to enhance disease detection in key regions.

关键词： HIV/AIDS Aged≥50 years China

Managing immune checkpoint inhibitor-associated gastritis: Insights and strategies

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World Journal of Gastroenterology 2024年第24期30卷 3120-3122页

作者： Li-Li yu Zhi-lin He Xin-Lai qian Department of Pathology The Third Affiliated Hospital of Xinxiang Medical UniversityXinxiang Medical UniversityXinxiang 453003Henan ProvinceChina Department of Basic Medical Sciences Xinxiang Medical UniversityXinxiang 453003Henan ProvinceChina

Immune checkpoint inhibitors(ICIs)are widely used due to their effectiveness in treating various ***-related adverse events(irAEs)are defined as adverse effects resulting from ICI *** irAEs are a common type of irAEs characterized by intestinal side effects,such as diarrhea and colitis,which may lead to the discontinuation of ICIs.

关键词： Immunotherapy Immune checkpoint inhibitor Immune checkpoint inhibitor-related gastritis Immune-related adverse events Autoimmune responses

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-lin Fan Feng Zhang qian Chen Hao-Chen Song Lu-yu Zhong yue-Xiang Dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and ***,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal *** this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection *** spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response *** with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal *** approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal *** accuracy level is ten times higher compared to density accuracy calculated using calibration ***,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration

BLS-identification:A device fingerprint classification mechanism based on broad learning for Internet of Things

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Digital Communications and Networks 2024年第3期10卷 728-739页

作者： yu Zhang Bei Gong qian Wang Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Information Science and Technology Zhengzhou Normal UniversityHenan450044China

The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security *** a network-level security authentication method,device fingerprint based on machine learning has attracted considerable attention because it can detect vulnerable devices in complex and heterogeneous access ***,flexible and diversified IoT devices with limited resources increase dif-ficulty of the device fingerprint authentication method executed in IoT,because it needs to retrain the model network to deal with incremental features or *** address this problem,a device fingerprinting mechanism based on a Broad Learning System(BLS)is proposed in this *** mechanism firstly characterizes IoT devices by traffic analysis based on the identifiable differences of the traffic data of IoT devices,and extracts feature parameters of the traffic packets.A hierarchical hybrid sampling method is designed at the preprocessing phase to improve the imbalanced data distribution and reconstruct the fingerprint *** complexity of the dataset is reduced using Principal Component Analysis(PCA)and the device type is identified by training weights using *** experimental results show that the proposed method can achieve state-of-the-art accuracy and spend less training time than other existing methods.

关键词： Device fingerprint Traffic analysis Class imbalance Broad learning system Access authentication