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Antioxidative potential of metformin:Possible protective mechanism against generating OH radicals

Frontiers of Environmental Science & Engineering 2021年第2期15卷 55-63页

作者： Huibin Guo ning Wang xiang Li College of Environmental Science and Engineering Xiamen University of TechnologyXiamen361024China Department of Environmental Science&Engineering Fudan UniversityShanghai 200032China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Fudan UniversityShanghai 20032China Environment Research Institute Shandong UniversityQingdao 266237China

Exposure to particulate matter(PM)can lead to the excessive accumulation of reactive oxygen species(ROS),which causes oxidative stress and endangers human *** this study,the effects of metformin on PM-induced radicals were investigated,and the antioxidation reaction mechanism of metformin was analyzed by the density functional theory(DFT)*** corresponding results revealed that the consumption rate of dithiothreitol(DTT)increased as the metformin concentration(0–40 mmol/L)increased under exposure to PM active ***,the OH radical content decreased as the metformin concentration *** result may be related to the consumption of PM-induced OH radicals by metformin,which promotes the DTT consumption ***,because the initiation reaction has a high barrier,the oxidation reaction rate between metformin and·O_(2)–is not very fast,although various catalysts may be present in the human ***,we found that the barrier of metformin induced by OH radicals is only 9.6 kcal/mol while the barrier of metformin induced by oxygen is 57.9 kcal/mol,which shows that the rate of the·OH-initiated oxidative reaction of metformin is much faster and that this reaction path occurs more *** sample analysis,the mean OH radical generation was 55 nmol/min/g(ranging from 5 to 105 nmol/min/g)on haze days and 30 nmol/min/g(ranging from 10 to 50 nmol/min/g)on non-haze ***,OH radical generation was higher on haze days than on neighboring non-haze *** together,all data suggest that metformin could consume the PM-induced radicals,such as OH radicals and·O_(2)–,thereby providing health protection.

关键词： Antioxidative potential Metformin Mechanism OH radical Health protection

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De-noising of radiation pressure signal generated by bubble oscillation based on ensemble empirical mode decomposition

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Journal of Hydrodynamics 2022年第5期34卷 849-863页

作者： xiang-hao Zheng Yu-ning Zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of EnergyPower and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The radiation pressure signals generated by the bubble oscillation are often utilized to recognize the characteristics of the target objects in many ***,these signals are easily contaminated by complex background *** order to accurately extract the effective components of the radiation pressure signal generated by the bubble oscillation,this paper proposes a de-noising procedure for the radiation pressure signal,based on the ensemble empirical mode decomposition(EEMD),the autocorrelation function and the modified wavelet soft-threshold de-noising *** order to verify the effectiveness of the procedure,the typical radiation pressure signal generated based on the Keller-Miksis model under the acoustic excitation is employed for the subsequent de-noising *** results of the qualitative analysis show that the amplitude and the period of the bubble oscillation can be clearly observed in the time-domain diagram of the de-noised signal based on the *** the quantitative analysis,the de-noised signal based on the EEMD has better performance with higher signal-to-noise ratio(SNR),smaller root-mean-square error,and larger correlation coefficient than that based on the wavelet transform(WT)and the empirical mode decomposition(EMD).Furthermore,with the increase of the complexity of the radiation pressure signal(e.g.,the increase of the dimensionless pressure amplitude of the acoustic wave and the decrease of the SNR of the input signal),the above three evaluation indexes of the de-noised signal based on the EEMD are all better than those based on the other two *** the signal is more complex,the de-noising capabilities of the WT,the EMD are greatly reduced,but the EEMD can still maintain the good de-noising capability,which shows the superiority of the signal de-noising procedure proposed in the present paper.

关键词： Radiation pressure cavitation bubble oscillation signal de-noising ensemble empirical mode decomposition(EEMD) autocorrelation function wavelet soft-threshold de-noising

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Real-world evidence on the efficacy and safety of vonoprazanamoxicillin dual therapy for Helicobacter pylori treatment in elderly patients

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World Journal of Gastroenterology 2025年第1期31卷 68-78页

作者： Wen Gao Jing-Wen Li Hui Ye Xue-Zhi Zhang Jian-xiang Liu Hong Cheng Department of Gastroenterology Peking University First HospitalBeijing 100034China School of Medicine Tsinghua MedicineTsinghua UniversityBeijing 100034China Department of Traditional Chinese Medicine and Integrative Medicine Peking University First HospitalBeijing 100034China

BACKGROUND A dual therapy regimen containing amoxicillin is a common treatment option for the eradication of Helicobacter pylori(***).While substantial research supports the efficacy and safety of vonoprazan and amoxicillin(VA)dual therapy in the general population,there is still a lack of studies specifically focusing on its safety in elderly *** To evaluate efficacy and safety of VA dual therapy as first-line or rescue treatment for *** in elderly *** As a real-world retrospective study,data were collected from elderly patients aged 60 years and above who accepted VA dual therapy(vonoprazan 20 mg twice daily+amoxicillin 1000 mg thrice daily for 14 days)for *** eradication in the Department of Gastroenterology at Peking University First Hospital between June 2020 and January *** status was evaluated by^(13)C-urease breath test 6 weeks after *** adverse events(AEs)during treatment were *** In total,401 cases were ***-one cases were excluded due to loss to follow-up,lack of re-examination,or unwillingness to take *** total of 380 included cases comprised 250 who received VA dual therapy as first-line treatment and 130 who received VA dual therapy as rescue *** was successfully eradicated in 239 cases(95.6%)in the first-line treatment group and 116 cases(89.2%)in the rescue treatment *** overall incidence of AEs was 9.5%for both ***,9.2%of patients experienced an AE in the first-line treatment group and 10.0%in the rescue treatment *** patients discontinued treatment due to AE,with a discontinuation rate of 1.3%.No serious AE *** The VA dual therapy regimen as a first-line treatment and a rescue therapy was effective and safe for elderly patients aged 60 and older.

关键词： Helicobacter pylori Vonoprazan Amoxicillin Dual therapy Elderly

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Effects of thiosulfate and dissolved oxygen on crevice corrosion of Alloy 690 in high-temperature chloride solution

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Journal of Materials Science & Technology 2021年第7期66卷 163-176页

作者： Fangqiang ning Jibo Tan Ziyu Zhang Xinqiang Wu xiang Wang En-Hou Han wei ke CAS Key Laboratory of Nuclear Materials and Safety Assessment Liaoning Key Laboratory for Safety and Assessment Technique of Nuclear MaterialsInstitute of Metal ResearchChinese Academy of SciencesShenyang J10016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

The crevice corrosion behavior of Alloy 690 was investigated in high-temperature chloride solution containing different concentrations of thiosulfate(S_(2)O_(3)^(2-)) and dissolved oxygen(DO). The S2O32- inhibited corrosion of Alloy 690 through consuming oxygen in aerated chloride solution. In deaerated chloride solution,the S_(2)O_(3)^(2-) was reduced to S° and S^(2-) and subsequently incorporated into the oxide films, which promoted the pitting corrosion at locations of both TiN inclusions and matrix inside the crevice during the crevice corrosion as well as influenced the composition and thickness of the oxide films. The effect mechanisms of S_(2)O_(3)^(2-) and DO on crevice corrosion in high-temperature chloride solution are discussed.

关键词： Alloy Crevice corrosion Pitting corrosion High-temperature corrosion Thiosulfate Oxidation

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Quark Transport Properties in the Region of Coexistence of Both Hadronic and QGP Phases

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Communications in Theoretical Physics 2001年第7期36卷 47-52页

作者： CHEN xiang-Jun LI Hong WANG Gang ZHANG wei-ning HUO Lei Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China

The physical picture of coexistence of both hadronic and QGP phases is given by Friedberg and T.D. Lee's nontopology soliton model. The transport properties of quark in color space and spin space in a system of two-ph... 详细信息

关键词： hadron, quark-gluon plasma, soliton, transport property

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Synchronization analysis on cascaded multilevel converters with distributed control

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 190-198页

作者： Ming-yao MA xiang-ning HE School of Electrical Engineering Zhej iang University Hangzhou 310027 China

Cascaded multilevel converters built with integrated modules have many advantages such as increased power density,flexible distributed control,multi-functionality,increased reliability and short design ***,the system performance will be affected due to the synchronization errors among each integrated *** paper analyzes the impact of the three kinds of synchronization errors on the whole system performance,as well as detailed synchronization *** valuable conclusions are derived from the theoretical analysis,simulations and experimental results.

关键词： Cascaded multilevel converter Integrated module Synchronization

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ISAR target recognition based on non-negative sparse coding

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Journal of Systems Engineering and Electronics 2012年第6期23卷 849-857页

作者： ning Tang Xunzhang Gao xiang Li Institute of Space Electronic Technology National University of Defense Technology Changsha 410073 E R. China

Aiming at technical difficulties in feature extraction for the inverse synthetic aperture radar （ISAR） target recognition, this paper imports the concept of visual perception and presents a novel method, which is based on the combination of non-negative sparse coding （NNSC） and linear discrimination optimization, to recognize targets in ISAR images. This method implements NNSC on the matrix constituted by the intensities of pixels in ISAR images for training, to obtain non-negative sparse bases which characterize sparse distribution of strong scattering centers. Then this paper chooses sparse bases via optimization criteria and calculates the corresponding non-negative sparse codes of both training and test images as the feature vectors, which are input into k neighbors classifier to realize recognition finally. The feasibility and robustness of the proposed method are proved by comparing with the template matching, principle component analysis （PCA） and non-negative matrix factorization （NMF） via simulations.

关键词： inverse synthetic aperture radar (ISAR) pre-processing non-negative sparse coding (NNSC) visual percep-tion target recognition.

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Liposomes as versatile agents for the management of traumatic and nontraumatic central nervous system disorders:drug stability,targeting efficiency,and safety

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Neural Regeneration Research 2025年第7期20卷 1883-1899页

作者： Mingyu Zhang Chunyu xiang Renrui Niu Xiaodong He Wenqi Luo Wanguo Liu Rui Gu Department of Orthopedic Surgery China-Japan Union Hospital of Jilin UniversityChangchunJilin ProvinceChina

Various nanoparticle-based drug delivery systems for the treatment of neurological disorders have been widely ***,their inability to cross the blood–brain barrier hampers the clinical translation of these therapeutic *** are nanoparticles composed of lipid bilayers,which can effectively encapsulate drugs and improve drug delivery across the blood–brain barrier and into brain tissue through their targeting and ***,they can potentially treat traumatic and nontraumatic central nervous system *** this review,we outlined the common properties and preparation methods of liposomes,including thin-film hydration,reverse-phase evaporation,solvent injection techniques,detergent removal methods,and microfluidics ***,we comprehensively discussed the current applications of liposomes in central nervous system diseases,such as Alzheimer's disease,Parkinson's disease,Huntington's disease,amyotrophic lateral sclerosis,traumatic brain injury,spinal cord injury,and brain *** studies related to liposomes are still in the laboratory stage and have not yet entered clinical ***,their application as drug delivery systems in clinical practice faces challenges such as drug stability,targeting efficiency,and ***,we proposed development strategies related to liposomes to further promote their development in neurological disease research.

关键词： Alzheimer's disease amyotrophic lateral sclerosis brain tumors central nervous system Huntington's disease liposome drug delivery neurological disorders Parkinson's disease spinal cord injury traumatic brain injury

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Interactions of the indigenous evergreen shrub Sabina vulgariswith coexisting species in the Mu Us sandland

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Journal of Plant Ecology 2013年第1期6卷 48-56页

作者： Lei ning Chun-xiang Liu wei-Ming He Fei-Hai Yu College of Nature Conservation Beijing Forestry UniversityBeijing 100083China State Key Lab of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Graduate University of Chinese Academy of Sciences Beijing 100039China

Aims Facilitation is widespread in plant communities and particularly common in highly stressful *** the semi-arid Mu Us sandland where soil water and nutrients are short and grazing is heavy,many species grow within the large patches formed by the dense individuals of the unpalatable clonal shrub Sabina vulgaris,the only natural evergreen shrub species in the Mu Us ***,the interactions between *** and these coexisting species remain unclear,and we hypothesize that *** can facilitate at least some species because within the patches vegetation is not grazed and soil water and nutrients may also be *** We measured the maximum height,coverage and number of individuals of each vascular species,little cover and thickness of biological crust at the soil surface in 1 m×1 m plots in three types of microsites associated with 40 patches of ***:(i)at the center,(ii)at the inner edge and(iii)outside the *** also took soil samples and measured soil water content and content of total N,P,K and organic *** Findings Soil water,nitrogen,organic matter and litter cover were the highest at the patch center,lowest outside the patches and intermediate at the inner edge of the patches,whereas thickness of biological crust was greater outside than at the center or at the inner *** the 32 species recorded,six species preferred to occur within the patches,suggesting that *** can facilitate these species most likely by grazing exclusion,increasing water and/or nitrogen resources in ***,most(19)species did not show preference and seven preferred ***,species richness,pooled cover and number of individuals of all species were greater outside than within the patches,and such effects did not vary with the size of the *** *** results suggest that the dominant interactions between *** and the coexisting species are *** findings add to our knowledge that fa

关键词： competition facilitation facilitative effects island of fertility plant-plant interactions resource islands semi-arid land

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The Cohomology of Line Bundles on Non-primary Hopf Manifolds

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Acta Mathematica Sinica,English Series 2007年第2期23卷 289-296页

作者： ning GAN xiang Yu ZHOU Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of Sciences

The purpose of the present paper is to give an elementary method for the computation of the cohomology groups Hq（X,Ω^p X（L））, （0 ≤q ≤ n） of an n-dimensional non-primary Hopf manifold X with arbitrary fundamental group. We use the method of Zhou to generalize the results for primary Hopf manifolds and non-primary Hopf manifold with an Abelian fundamental group.

关键词： non-primary Hopf manifold cohomology line bundles Douady sequence

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