检索结果-南通市图书馆

Hyperoside Suppresses Lipopolysaccharide-induced Inflammation and Apoptosis in Human Umbilical Vein Endothelial Cells

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Medical Science 2018年第2期38卷 222-228页

作者： Yan-qiang ZHOU yin-tao zhao Xiao-yan zhao Cui LIANG Ya-wei XU Ling LI Yuan LIU Hai-bo YANG Department of Cardiology the First Affiliated Hospital of Zhengzhou University Henan 450052 China

Finding the novel drug from the effective components of traditional Chinese herbal medicine is a hotspot of the modem pharmacological research. Hyperoside （HYP） belongs to flavonoid glycosides, and it has various properties, such as anti-inflammation, anti-spasm, anti-diuretic, antitussive, lowering blood pressure, and lowering cholesterol effects as well as protective effects for the cardiac and cerebral blood vessels. The purpose of this study was to investigate the effects of HYP on inflammatory and apoptotic responses in vascular endothelial cells stimulated by lipopolysaccharide （LPS） and further to identify the possible mechanisms underlying these effects. In our study, human umbilical vein endothelial cells （HUVECs） were stimulated with 1 Bg/mL LPS in the presence or absence of HYP （10, 20 and 50 μmol/L）. Our results indicated that HYP alone exerted no cytotoxicity on HUVECs, while it had an upregulatory effect on the viability of HUVECs induced by LPS in a dose-dependent manner; increased mRNA expression of IL-1β, IL-6, TNFα and iNOS induced by LPS was attenuated after treatment with HYP both in a dose- and time-dependent manner; LPS-induced HUVECs apoptosis and cleaved-caspase 8, 9, 3 were all significantly reduced by HYP. Furthermore, the possible pathway involved in apoptosis and inflammation by HYP was detected, and the results showed that when treated with HYP, LPS-induced mitochondrial membrane instability was significantly inhibited through up-regulation of Bcl-2 and down-regulation of Bax. Furthermore, the expression of TLR4 and the phosphorylation of IκBα and p65 in LPS-treated cells were blocked by HYP. Our results suggested that HYP treatment prevented HUVECs from LPS- induced inflammation and apoptosis responses, which might be mediated by inhibiting TLR4/ NFκB pathway.

关键词： hyperoside lipopolysaccharide inflammation apoptosis human umbilical veinendothelial cells

Investigation of the Corrosion and Passive Behavior of HP-13Cr Stainless Steel in Formate Annulus Protection Fluid

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 1087-1103页

作者： Jidong Wang Tengfei yin Wenlong Qi Xuanpeng Li Yang zhao tao Zhang Fuhui Wang Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang110819China State Key Laboratory of Performance and Structural Safety for Petroleum Tubular Goods and Equipment Materials Tubular Goods Research InstituteCNPCXi’an710077China

The corrosion and passive behavior of HP-13Cr stainless steel(HP-13Cr SS)in formate annulus protection fluid was ***-13Cr SS exhibited good passive behavior in clean formate annulus protection fluid,which was attributed to a thinner and more dense passive film mainly composed of Cr_(2)O_(3).In the formation water solution,the passive film was composed of metastable Cr(OH)3,which was explained by the isoelectric point theory,resulting in the deterioration of the passive behavior of HP-13Cr *** the formation water penetrated the formate annulus protection fluid,a large number of loose FeCO_(3)particles formed in the corrosion scales,thus HP-13Cr SS suffered severe ***,avoiding formation water penetrating the formate annulus protection fluid is conducive to improving the service life of HP-13Cr SS oil tubes in extremely aggressive environment.

关键词： HP-13Cr SS Passive behavior Formate annulus protection fluid Isoelectric point

Chemoselective and Living/Controlled Polymerization of Alkenyl Methacrylates by the Phosphonium Ylide/Organoaluminum Lewis Pairs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第2期42卷 159-167,I0005页

作者： Zhi-Kang Chen Wu-Chao zhao Yi-Ling zhao Cong-Lei Liu Liu-yin Jiang Yue-tao Zhang Hong-Ping Zhu State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012China

Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been *** P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were *** the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy *** pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)*** thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.

关键词： Phosphonium ylide Alkenyl methacrylate Chemoselectivity Living/controlled polymerization Post-functionalization

维普期刊数据库

Modulating oxygen vacancy concentration for selective growth of semiconducting single-walled carbon nanotubes with narrow diameters

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第7期174卷 44-54页

作者： Lei Yang Tingkai zhao Abdul Jalil Huijun Luo tao Jiang Yuan Shu Yazhou yin Weiyu Jia NPU-NCP Joint International Research Center on Advanced Nanomaterials&Defects Engineering Shaanxi Engineering Laboratory for Graphene New Carbon Materials and ApplicationsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Physics Allama Iqbal Open University IslamabadPakistan

Semiconducting single-walled carbon nanotubes(s-SWCNTs)with narrow diameters are promising for future applications in many fields,especially in nanoelectronics and *** this study,the oxygen vacancy concentration modulating strategy was utilized for growing narrow diameters s-SWCNTs by the chemical vapor deposition(CVD)*** Fe_(0.01)Mg_(0.99)O solid solution based catalyst was syn-thesized to anchor the Fe particles and inhibit aggregation for growing SWCNTs with uniform ***_(2)was introduced into the catalyst to provide oxygen vacancies through H_(2)*** oxygen vacancies could form an oxidative environment during the growth of SWCNTs,and the chemically active metallic carbon nanotube caps are selectively etched away under this *** Fe/Ce molar ratio and H2 prereduction time were optimized to modulate the oxygen vacancy ***,us-ing the Fe_(0.01)Mg_(0.99)O/CeO_(2)(3)catalyst with 10 min of H_(2)prereduction time,high purity s-SWCNTs with diameters ranging from 1.41 to 1.71 nm and a content of 95.1%were obtained with high selectivity and carbon yield(1.33 wt%).The mechanism behind this phenomenon was elucidated through experimental characterizations and first-principle simulations,further expanding the understanding of the growth of s-SWCNTs through the modulation of oxygen vacancy concentration.

关键词： Semiconducting single-walled carbon nanotubes Oxygen vacancy concentration Fe_(0.01)Mg_(0.99)O/CeO_(2)catalyst

Towards catalytic reactions of Cu single-atom catalysts:Recent progress and future perspective

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第2期35卷 197-207页

作者： Yitao zhao Lei tao Jiangsu Province Engineering Research Center of Special Functional Textile Materials Changzhou Vocational Institute of Textile and GarmentChangzhou 213164China Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterSchool of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China

One of the urgent and challenging topics in diversified sustainable energy conversion is the development of high-performance,low-cost,and well durable *** single-atom catalysts(SACs)have become promising catalysts for diversified sustainable energy conversion due to their capability to maximize the utilization efficiency,acquire modulated electronic structure and optimized binding strength with *** this review,we have provided an interview of the recent progress achieved in the field of electrocatalysis,photocatalysis,and heterogeneous reaction based on Cu *** by this review,we have summarized some advanced synthetic strategies for the construction of Cu ***,the performance-improving strategies are discussed in terms of the coordination environments of the reaction center,reaction mechanism and selectivity,based on free energy diagram and electron structure ***,the remaining issues,challenges,and opportunities of Cu SACs are also provided,affording a perspective for future *** review not only offers us a deep understanding on the catalytic mechanism of Cu SACs for energy conversion,but also encourages more endeavors in prompting their practical application.

关键词： Cu SACs Energy conversion Catalysis Coordination environment

维普期刊数据库

The Strategic Analysis of Demand Forecast-Sharing in a Hybrid-Format Online Platform Supply Chain

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2024年第3期33卷 281-310页

作者： Jing zhao Zijun yin Guobiao Zhou School of Mathematical Sciences Tiangong UniversityTianjin300387China

This paper examines the optimal forecast-sharing strategy in a hybrid-format online platform supply chain where a supplier sells a product through agency format and reselling format provided by a platform retailer who possesses demand forecasts from two *** asymmetry and co-opetitive relationship arise between the platform retailer and the supplier,which affect their operational decisions and the supply chain’s *** improve supply chain efficiency,we compare different forecast-sharing strategies(i.e.,no forecast sharing,sharing a single forecast,and sharing two forecasts),and analyze the effects of co-opetitive parameters on the optimal forecast-sharing *** analysis shows that forecast sharing is always beneficial to the supplier,and sharing two forecasts is more beneficial than sharing a single *** for the platform retailer and the whole supply chain,forecast sharing is beneficial only under certain conditions,depending on the co-opetitive *** optimal forecast-sharing strategy is the result of a combination of the negative effect of double marginalization in reselling channel and the positive effect of responding pricing to demand uncertainty in agency *** illustrate the parameter regions of the platform retailer’s voluntary sharing,contract sharing,and no sharing,and also find that higher channel competition intensity,higher market share of agency channel,and higher commission rate can promote the platform retailer’s voluntary *** study extends the research scope of demand forecast-sharing and sheds light on the decision-making processes for managing a hybrid-format online platform supply chain.

关键词： Supply chain management hybrid-format online platform demand forecast-sharing co-opetitive relationship channel competition intensity

cKBET:assessing goodness of batch effect correction for single-cell RNA-seq

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2024年第1期18卷 215-228页

作者： Yameng zhao yin GUO Limin LI School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China

Single-cell RNA sequencing reveals the gene structure and gene expression status of a single cell,which can reflect the heterogeneity between ***,batch effects caused by non-biological factors may hinder data integration and downstream *** the batch effect can be evaluated by visualizing the data,which actually is subjective and *** this work,we propose a quantitative method cKBET,which considers the batch and cell type information *** cKBET method accesses batch effects by comparing the global and local fraction of cells of different batches in different cell *** verify the performance of our cKBET method on simulated and real biological data *** experimental results show that our cKBET method is superior to existing methods in most *** general,our cKBET method can detect batch effect with either balanced or unbalanced cell types,and thus evaluate batch correction methods.

关键词： single-cell RNA-seq dataset b batch effect assessment cKBET method

A sub-grid scale model for Burgers turbulence based on the artificial neural network method

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Theoretical & Applied Mechanics Letters 2024年第3期14卷 162-165页

作者： Xin zhao Kaiyi yin Department of Mechanics Beijing Institute of TechnologyBeijing 100081China

The present study proposes a sub-grid scale model for the one-dimensional Burgers turbulence based on the neuralnetwork and deep learning *** filtered data of the direct numerical simulation is used to establish thetraining data set,the validation data set,and the test data *** artificial neural network(ANN)methodand Back Propagation method are employed to train parameters in the *** developed ANN is applied toconstruct the sub-grid scale model for the large eddy simulation of the Burgers turbulence in the *** proposed model well predicts the time correlation and the space correlation of the Burgers turbulence.

关键词： Artificial neural network Back propagation method Burgers turbulence Large eddy simulation Sub-grid scale model

维普期刊数据库

Essentially Commuting Truncated Toeplitz Operators

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第10期40卷 2453-2480页

作者： Xi zhao tao YU School of Mathematics and Science Hebei GEO University School of Mathematical Sciences Dalian University of Technology

A model space is a subspace of the Hardy space which is invariant under the backward shift,and a truncated Toeplitz operator is the compression of a Toeplitz operator on some model space. In this paper we prove a necessary and sufficient condition for the commutator of two truncated Toeplitz operators on a model space to be compact.

关键词： 47B32 47B35 commutator compact operator maximal ideal space model space Truncated Toeplitz operator