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Modulating electronic structure of Fe atomic cluster by Cu single-atom sites for enhanced oxygen reduction reaction
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作者 Jing Wu Jian Rong +6 位作者 Wang-Yi Chen Chao-Sheng Wang Chu-Jun Feng Huai-Sheng Ao Cheng-Zhang Zhu Yu-Zhe Zhang Zhong-Yu Li 《Rare Metals》 2025年第9期6279-6291,共13页
Regulating the electronic structure and oxygencontaining intermediates adsorption behavior on Fe-based catalysts is of great significance to cope with the sluggish oxygen reduction reaction(ORR)kinetics,but it still r... Regulating the electronic structure and oxygencontaining intermediates adsorption behavior on Fe-based catalysts is of great significance to cope with the sluggish oxygen reduction reaction(ORR)kinetics,but it still remains a great challenge.In this work,Fe atom clusters(Fe_(AC))modified by high-density Cu single atoms(Cu_(SA))in a N,S-doped porous carbon substrate(Fe_(AC)/Cu_(SA)@NCS)is reported for enhanced ORR electrocatalysis.Fe_(AC)/Cu_(SA)@NCS exhibits excellent ORR performance with a half-wave potential(E_(1/2))of 0.911 V,a high four-electron process selectivity and excellent stability.The ORR performance is also verified in the Fe_(AC)/Cu_(SA)@NCS-based Zn-air battery,which shows a high peak power density of 192.67 mW cm^(-2),a higher specific capacity of 808.3 mAh g^(-1)and impressive charge-discharge cycle stability.Moreover,density functional theory calculations show that Cu single atoms synergistically modulate the electronic structure Fe active atoms in Fe atomic clusters,reducing the energy barrier of the rate-determining step(i.e.,*OH desorption)on Fe_(AC)/Cu_(SA)@NCS.This work provides an effective way to regulate the electronic structure of Fe-based catalysts and optimize their electrocatalytic activity based on the introduction of a second metal source. 展开更多
关键词 Atom cluster Single atom modulating electronic structure Oxygen reduction reaction Density functional theory
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M2 macrophages-derived exosomes for osteonecrosis of femoral head treatment:modulating neutrophil extracellular traps formation and endothelial phenotype transition
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作者 Guanzhi Liu Ruomu Cao +5 位作者 Qimeng Liu Heng Li Peng Yan Kunzheng Wang Run Tian Pei Yang 《Bone Research》 2025年第4期855-865,共11页
Exosomes have shown good potential in ischemic injury disease treatments.However,evidence about their effect and molecular mechanisms in osteonecrosis of femoral head(ONFH)treatment is still limited.Here,we revealed t... Exosomes have shown good potential in ischemic injury disease treatments.However,evidence about their effect and molecular mechanisms in osteonecrosis of femoral head(ONFH)treatment is still limited.Here,we revealed the cell biology characters of ONFH osteonecrosis area bone tissue in single cell scale and thus identified a novel ONFH treatment approach based on M2 macrophages-derived exosomes(M2-Exos).We further show that M2-Exos are highly effective in the treatment of ONFH by modulating the phenotypes communication between neutrophil and endothelium including neutrophil extracellular traps formation and endothelial phenotype transition.Additionally,we identified that M2-Exos’therapeutic effect is attributed to the high content of miR-93-5p and constructed miR-93-5p overexpression model in vitro and in vivo based on lentivirus and adenoassociated virus respectively.Then we found miR-93-5p can not only reduce neutrophil extracellular traps formation but also improve angiogenic ability of endothelial cells.These results provided a new theoretical basis for the clinical application of ONFH therapeutic exosomes. 展开更多
关键词 modulating phenotypes comm cell biology characters ischemic injury disease miR p osteonecrosis femoral neutrophil extracellular traps macrophages derived exosomes endothelial phenotype transition
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Modulating electronic structure of g-C_(3)N_(4) hosted Co-N_(4) active sites by axial phosphorus coordination for efficient overall H_(2)O_(2) photosynthesis from oxygen and water
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作者 Shinuo Liang Fengjun Li +2 位作者 Fei Huang Xinyu Wang Shengwei Liu 《Chinese Journal of Catalysis》 2025年第9期81-95,共15页
Single-atom catalysts are promising for H_(2)O_(2) photosynthesis from O_(2) and H_(2)O,but their efficiency is still limited by the ill-defined electronic structure.In this study,Co single-atoms with unique four plan... Single-atom catalysts are promising for H_(2)O_(2) photosynthesis from O_(2) and H_(2)O,but their efficiency is still limited by the ill-defined electronic structure.In this study,Co single-atoms with unique four planar N-coordination and one axial P-coordination(Co-N_(4)P_(1))are decorated on the lateral edges of nanorod-like crystalline g-C_(3)N_(4)(CCN)photocatalysts.Significantly,the electronic structures of central Co as active sites for O_(2) reduction reaction(ORR)and planar N-coordinator as active sites for H_(2)O oxidation reaction(WOR)in Co-N_(4)P_(1) can be well regulated by the synergetic effects of introducing axial P-coordinator,in contrast to the decorated Co single-atoms with only four planar N-coordination(Co-N_(4)).Specifically,directional photoelectron accumulation at central Co active sites,induced by an introduced midgap level in Co-N_(4)P_(1),mediates the ORR active sites from 4e–-ORR-selective terminal–NH_(2) sites to 2e–-ORR-selective Co sites,moreover,an elevated d-band center of Co 3d orbital strengthens ORR intermediate*OOH adsorption,thus jointly facilitating a highly selective and active 2e^(–)-ORR pathway to H_(2)O_(2) photosynthesis.Simultaneously,a downshifted p-band center of N_(2)p orbital in Co-N_(4)P_(1) weakens WOR intermediate*OH adsorption,thus enabling a preferable 2e^(–)-WOR pathway toward H_(2)O_(2) photosynthesis.Subsequently,Co-N_(4)P_(1) exhibits exceptional H_(2)O_(2) photosynthesis efficiency,reaching 295.6μmol g^(-1) h^(-1) with a remarkable solar-to-chemical conversion efficiency of 0.32%,which is 15 times that of Co-N_(4)(19.2μmol g^(-1) h^(-1))and 10 times higher than CCN(27.6μmol g^(-1) h^(-1)).This electronic structure modulation on single-atom catalysts offers a promising strategy for boosting the activity and selectivity of H_(2)O_(2) photosynthesis. 展开更多
关键词 Crystalline carbon nitride Coordination engineering Single atom Co-N_(4)P_(1)active sites modulating electronic structure Overall H_(2)O_(2)photosynthesis
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Synergistic effects of Fe single atoms and Fe nanoparticles modulating the electronic configuration for photocatalytic water treatment
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作者 Min Dai Ziwen Zhao +4 位作者 Yaru Li Shuaiqi Zhang Jingyun Fang Chun Hu Fan Li 《Journal of Materials Science & Technology》 2025年第16期91-100,共10页
The introduction of metal single atoms(SAs)and nanoparticles(NPs)are effective approaches to mod-ify electronic configuration of semiconductors,whereas recognizing the synergistic effects of metal SAs and NPs are stil... The introduction of metal single atoms(SAs)and nanoparticles(NPs)are effective approaches to mod-ify electronic configuration of semiconductors,whereas recognizing the synergistic effects of metal SAs and NPs are still challenging in photocatalytic water purification.Herein,a general strategy is achieved by subsequentially anchoring Fe SAs and Fe NPs in graphitic carbon nitride.The modification of Fe SAs and Fe NPs improves the energy band structure and constructs a gradient charge polarization,directly expanding the optical absorption range and facilitating the efficient separation and transfer of charge car-riers.With the assistance of the gradient charge polarization,pollutants are readily oxidated by h+,which strengthens the continuous reduction of O2 on Fe NPs for pollutant oxidation in water.This work rein-forces the synergistic effect of SAs and NPs on electronic configuration modulation at the atomic level,which exhibits great potential for the construction of an efficient and sustainable water purification sys-tem. 展开更多
关键词 Single atoms NANOPARTICLES Synergistic effects PHOTOCATALYSIS Electronic configuration modulation
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Investigation of edge states variation in valley photonic crystals by modulating the refractive index of domain walls
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作者 ZHANG Run ZHONG Xingli +2 位作者 LIN Zhongxi QIU Weibin SU Hui 《Optoelectronics Letters》 2025年第3期160-166,共7页
Realizing the valley Hall effect by breaking the spatial inversion symmetry of photonic systems has become a cutting-edge field of micro-nano-optics,since the valley degree of freedom was introduced into photonic syst... Realizing the valley Hall effect by breaking the spatial inversion symmetry of photonic systems has become a cutting-edge field of micro-nano-optics,since the valley degree of freedom was introduced into photonic system.Various novel devices based on the domain walls of the valley photonic crystals have also been demonstrated.In this article,we investigate the variation of edge states by the modulation of refractive index within the domain walls,and the geometric difference between the dielectric columns of the sublattices.Straight photonic crystal waveguides with three types of domain walls(bearded,zigzag,armchair)are constructed.Simulation results show that the creation of a double-edge state in the band diagram results in two windows of stable transmission in tunable bands.Our findings might have significant implications in the field of novel optical devices. 展开更多
关键词 modulation refractive index domain walls variation edge states breaking spatial inversion symmetry valley degree freedom photonic crystals geometric difference dielectric columns photonic systems
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Photo-induced Ag modulating carbon dots:Greatly improved fluorescent properties and derived sensing application
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作者 Yuwei Wang Ye Li +7 位作者 Guixiang Yang Xiaofeng Yang Chenglu Yan Huaqiao Peng Huiyong Wang Juan Du Baozhan Zheng Yong Guo 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第1期338-342,共5页
Carbon dots(CDs)have been attracted much attention and widely studied due to their excellent fluorescence(FL)properties,better biocompatibility and outstanding photo/chemical stability.However,the disadvantage of lowe... Carbon dots(CDs)have been attracted much attention and widely studied due to their excellent fluorescence(FL)properties,better biocompatibility and outstanding photo/chemical stability.However,the disadvantage of lower quantum yield(QY)still limits its wide application.Herein,we reported a novel and convenient strategy to prepare photo-induced Ag/CDs(p-Ag/CDs)by irradiating the mixed Ag+and hydrophobic CDs(h-CDs)acetone solution with ultraviolet(UV)light.The obtained p-Ag/CDs exhibit a greatly enhanced FL emission together with a blue shift(460 nm)than h-CDs(520 nm).The QY of p-Ag/CDs is measured to be 51.1%,which is 10.4 times higher than that of h-CDs(4.9%),indicating that photo-induced Ag modulation can effectively improve the optical properties of CDs.The mechanisms for the FL enhancement and blue shift of h-CDs are studied in detail.The results prove that the greatly enhanced FL emission is from the generated Ag nanoparticles(AgNPs)by UV light irradiation based on metal-enhanced fluorescence(MEF),and the increased oxygen-contained groups in this process lead to the blue shift in CDs fluorescence.Interestingly,the p-Ag/CDs exhibit higher sensitivity and selectivity for sulfide ions(S2-)detection than that of h-CDs,which have a lower response to S2-.This work not only offers a novel strategy to improve the FL properties of materials but also endows them with new functions and broadens their application fields. 展开更多
关键词 Carbon dots Photo-induced Ag modulating Fluorescent enhancement High quantum yield Derived sensing application Sulfide determination
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Lactobacillus from fermented bamboo shoots prevents inflammation in DSS-induced colitis mice via modulating gut microbiome and serum metabolites
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作者 Xiangru Liu Xiaoling Lu +6 位作者 Hao Nie Jing Yan Zhiwen Ma Hailin Li Shixin Tang Qi Yin Jingfu Qiu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2833-2846,共14页
Fermented bamboo shoots(FBS)is a region-specific food widely consumed in Southwestern China,with Lactobacillus as the predominant fermenting bacteria.However,the probiotic potential of Lactobacillus derived from FBS r... Fermented bamboo shoots(FBS)is a region-specific food widely consumed in Southwestern China,with Lactobacillus as the predominant fermenting bacteria.However,the probiotic potential of Lactobacillus derived from FBS reminds largely unexplored,especially for diseases with a low prevalence in areas consuming FBS,namely,inflammatory bowel disease.In this study,Lactiplantibacillus pentosus YQ001 and Lentilactobacillus senioris YQ005 were screening by in vitro probiotic tests to further investigate the probioticlike bioactivity in dextran sulfate sodium(DSS)-induced ulcerative colitis(UC)mouse.They exhibited more positive probiotic effects than Lactobacillus rhamnosus GG in preventing intestinal inflammatory response.The results revealed that both strains improved the abundance of deficient intestinal microbiota in UC mice,including Muribaculaceae and Akkermansia.In the serum metabolome,they modulated the DSS-disturbed levels of metabolites,with significant increment of cinnamic acid.Meanwhile,they reduced the expression levels of interleukin-1β(IL-1β),interleukin-6(IL-6)inflammatory factors and increased zonula occludens-1(ZO-1),Occludin,and cathelicidin-related antimicrobial peptide(CRAMP)in the colon.Consequently,these results demonstrated that Lactobacillus spp.isolates derived from FBS showed promising probiotic activity based on the gut microbiome homeostasis modulation,anti-inflammation and intestinal barrier protection in UC mice. 展开更多
关键词 Fermented bamboo shoots LACTOBACILLUS Probiotic activity Gut microbiome modulation Ulcerative colitis
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Modulating the microstructure and surface chemistry of carbocatalysts for oxidative and direct dehydrogenation: A review 被引量:5
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作者 赵忠奎 葛桂芳 +2 位作者 李伟作 郭新闻 王桂茹 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第5期644-670,共27页
The catalytic performance of solid catalysts depends on the properties of the catalytically active sites and their accessibility to reactants, which are significantly affected by the microstructure(morphology, shape,... The catalytic performance of solid catalysts depends on the properties of the catalytically active sites and their accessibility to reactants, which are significantly affected by the microstructure(morphology, shape, size, texture, and surface structure) and surface chemistry(elemental components and chemical states). The development of facile and efficient methods for tailoring the microstructure and surface chemistry is a hot topic in catalysis. This contribution reviews the state of the art in modulating the microstructure and surface chemistry of carbocatalysts by both bottom‐up and top‐down strategies and their use in the oxidative dehydrogenation(ODH) and direct dehydrogenation(DDH) of hydrocarbons including light alkanes and ethylbenzene to their corresponding olefins, important building blocks and chemicals like oxygenates. A concept of microstructure and surface chemistry tuning of the carbocatalyst for optimized catalytic performance and also for the fundamental understanding of the structure‐performance relationship is discussed. We also highlight the importance and challenges in modulating the microstructure and surface chemistry of carbocatalysts in ODH and DDH reactions of hydrocarbons for the highly‐efficient, energy‐saving,and clean production of their corresponding olefins. 展开更多
关键词 Carbocatalysis MICROSTRUCTURE Surface chemistry MODULATION DEHYDROGENATION OLEFIN
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Lysine-specific demethylase 1 inhibitor rescues the osteogenic ability of mesenchymal stem cells under osteoporotic conditions by modulating H3K4 methylation 被引量:13
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作者 Longwei Lv Wenshu Ge +4 位作者 Yunsong Liu Guanyou Lai Hao Liu Wenyue Li Yongsheng Zhou 《Bone Research》 SCIE CAS CSCD 2016年第4期217-231,共15页
Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulatio... Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulation plays an important role in the developmental origins of osteoporosis; however, few studies have investigated the potential of epigenetic therapy to improve or rescue the osteogenic ability of bone marrow mesenchymal stem cells(BMMSCs) under osteoporotic conditions. Here, we investigated pargyline, an inhibitor of lysine-specific demethylase 1(LSD1), which mainly catalyzes the demethylation of the di- and mono-methylation of H3K4. We demonstrated that 1.5 mmol·Lpargyline was the optimal concentration for the osteogenic differentiation of human BMMSCs. Pargyline rescued the osteogenic differentiation ability of mouse BMMSCs under osteoporotic conditions by enhancing the dimethylation level of H3K4 at the promoter regions of osteogenesis-related genes. Moreover, pargyline partially rescued or prevented the osteoporotic conditions in aged or ovariectomized mouse models, respectively. By introducing the concept of epigenetic therapy into the field of osteoporosis, this study demonstrated that LSD1 inhibitors could improve the clinical practice of MSC-based bone tissue engineering and proposes their novel use to treat osteoporosis. 展开更多
关键词 Lysine-specific demethylase 1 inhibitor rescues the osteogenic ability of mesenchymal stem cells under osteoporotic conditions by modulating H3K4 methylation OM stem BMD
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Modulating intestinal mucus barrier for nanoparticles penetration by surfactants 被引量:2
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作者 Xin Zhang Wei Dong +7 位作者 Hongbo Cheng Meixia Zhang Yongqiang Kou Jian Guan Qiaoyu Liu Mingyue Gao Xiuhua Wang ShiruiMao 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第5期543-551,共9页
Improving peroral delivery efficiency is always a persistent goal for both small-molecule and macromolecular drug development. However,intestinal mucus barrier which greatly impedes drug-loaded nanoparticles penetrati... Improving peroral delivery efficiency is always a persistent goal for both small-molecule and macromolecular drug development. However,intestinal mucus barrier which greatly impedes drug-loaded nanoparticles penetration is commonly overlooked. Therefore,in this study,taking fluorescent labeled PLGA(poly(lactic-co-glycolic acid)) nanoparticles as a tool,the influence of anionic and nonionic surfactants on mucus penetration ability of nanoparticles and their mucus barrier regulating ability were studied. The movement of PLGA nanoparticles in mucus was tracked by multiple particles tracking method(MPT).Alteration of mucus properties by addition of surfactants was evaluated by rheology and morphology study. Rat intestinal villus penetration study was used to further evaluate penetration enhancement of nanoparticles. The effective diffusivities of the nanoparticles in surfactants pretreated mucus were increased by 2–3 times and the mucus barrier regulating capacity was also surfactant type dependent. Sodium dodecyl sulfate(SDS) increased the complex viscosity and viscoelastic properties of mucus,but poloxamer presented a decreased trend. Tween 80 maintained the rheological property of the mucus. With the mucus barrier regulated by surfactants,the penetration of nanoparticles in intestinal villus was obviously increased. In summary,the mucus penetration ability of nanoparticles could be enhanced by altering mucus microenvironment with surfactants. Tween 80 which largely retains the original mucus rheology and morphology properties may be a promising candidate for facilitating nanoparticle penetration through the mucus barrier with good safety profile. 展开更多
关键词 MUCUS BARRIER MUCUS modulating agents RHEOLOGY PLGA NANOPARTICLES SURFACTANTS
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The modulating effect of N coordination on single-atom catalysts researched by Pt-N_(x)-C model through both experimental study and DFT simulation 被引量:2
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作者 Mengmeng Fan Jiewu Cui +10 位作者 Junjie Zhang Jingjie Wu Shuangming Chen Li Song Zixing Wang Ao Wang Robert Vajtai Yucheng Wu Pulickel MAjayan Jianchun Jiang Dongping Sun 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第32期160-167,共8页
N-doped carbon-based single-atom catalysts(NC-SACs) are widely researched in various electrochemical reactions due to high metal atom utilization and catalytic activity.The catalytic activity of NC-SACs originates fro... N-doped carbon-based single-atom catalysts(NC-SACs) are widely researched in various electrochemical reactions due to high metal atom utilization and catalytic activity.The catalytic activity of NC-SACs originates from the coordinating structure between single metal site(M) and the doped nitrogen(N) in carbon matrix by forming M-N_(x)-C structure(1≤x≤4).The M-N4-C structure is widely considered to be the most stable and effective catalytic site.However,there is no in-depth research for the "x" modulation in Pt-Nx-C structure and the corresponding catalytic properties.Herein,atomically dispersed Pt on N-doped carbon(Pt-NC) with Pt-Nx-C structure(1≤x≤4),as a research model,is fabricated by a ZIF-8 template and applied to catalytic oxygen reduction.Different carbonization temperatures are used to control N loss,and then modulate the N coordination of Pt-Nx-C structure.The Pt-NC has the predictable low half-wave potential(E_(1/2)) of 0.72 V vs RHE compared to the Pt/C 20% of 0.81 V due to low Pt content.Remarkably,the Pt-NC shows a high onset potential(1.10 V vs RHE,determined for j=-0.1 mA cm^(2)) and a high current density of 5.2 mA cm^(-2),more positive and higher than that of Pt/C 20%(0.96 V) and 4.9 mA cm^(-2),respectively.As the structural characterization and DFT simulation confirmed,the reducing PtN coordination number induces low valence of Pt atoms and low free energy of oxygen reduction,which is responsible for the improved catalytic activity.Furthermore,the Pt-NC shows high mass activity(172 times higher than that of Pt/C 20%),better stability and methanol crossover resistance. 展开更多
关键词 modulating effect N coordination Single-atom catalysts Pt-N_(x)-C model DFT simulation
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Rb1 protects endothelial cells from hydrogen peroxide-induced cell senescence by modulating redox status 被引量:15
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作者 LIU Ding-hui~1,CHEN Yan-ming~2,LIU Yong~1,HAO Bao-shun~1, ZHOU Bin~1,WU Lin~1,WANG Min~1,CHEN Lin~1,WU Wei-kang~3,QIAN Xiao-xian~1 (1.Department of Cardiology,The Third Affiliated Hospital of Sun Yat-sen University,Guagnzhou 510630 2.Department of Endocrinology,The Third Affiliated Hospital of Sun Yat-sen, Guagnzhou 510630 3.Institute Integrated Traditional Chinese and Western Medicine,Sun Yat-sen University,Guagnzhou 510630) 《岭南心血管病杂志》 2011年第S1期224-224,共1页
Objectives Endothelial senescence has been proposed to be involved in endothelial dysfunction and atherogenesis. This study investigates the effects of ginsenoside Rbl, a major constituent of ginseng,on H<sub>2&... Objectives Endothelial senescence has been proposed to be involved in endothelial dysfunction and atherogenesis. This study investigates the effects of ginsenoside Rbl, a major constituent of ginseng,on H<sub>2</sub>O<sub>2</sub>-induced endothelial senescence.Methods Primary human umbilical vein endothelial cells(HUVECs) senescence was induced by H<sub>2</sub>O<sub>2</sub> as judged by senescence-associated P-galactosidase assay (SA-P-gal).Fntracellur superoxide dismutase(S0D1) activity and malondialdehyde(MDA) level were determined by commercial kit.S0D1 mRNA and protein expression were analyzed by real time PCR and Western blot.Reactive oxygen species(ROS) were determined by flow cytometry.Results Rb1 was found to reverse endothelial senescence,as witnessed by a significant decrease of senescent cell numbers. Rbl could markedly increase intracellular SOD activity, decrease the MDA level,and suppress the generation of intracellular ROS in H<sub>2</sub>O<sub>2</sub>-treated HUVECs.Consistent with these findings,Rbl can effectively restore SOD1 mRNA and protein expression which decreased in H<sub>2</sub>O<sub>2</sub> treated cells. Conclusions Our report demonstrates thatRbl can exert reversal effects on H<sub>2</sub>O<sub>2</sub>-induced cellular senescence through modulating cellular redox status. 展开更多
关键词 Rb1 protects endothelial cells from hydrogen peroxide-induced cell senescence by modulating redox status CELL
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Cobalt valence modulating in CoO_(x) incorporated carbon nanofiber for enhanced glucose electrooxidation 被引量:1
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作者 Jiadong Hu Hao Lu +5 位作者 Mingsong Li Gang Xiao Min Li Xuemei Xiang Zhisong Lu Yan Qiao 《Materials Reports(Energy)》 2022年第2期86-93,共8页
Glucose fuel cells(GFCs)driven by abiotic catalysts are promising green power sources for portable or wearable devices.In this work,a CoO_(x)incorporated carbon nanofiber(CoO_(x)@CNF)catalyst with mixed valences cobal... Glucose fuel cells(GFCs)driven by abiotic catalysts are promising green power sources for portable or wearable devices.In this work,a CoO_(x)incorporated carbon nanofiber(CoO_(x)@CNF)catalyst with mixed valences cobalt oxides have been developed through partial oxidation of pyrolyzed electrospun Co^(2+)/poly acrylonitrile fibers.The cobalt valence modulating could be achieved via regulating the incorporation ratio of cobalt acetate in precursors or the oxidation temperature of the pyrolyzed fibers.Electrocatalytic analyses show that the presence of CoO in CoO_(x)@CNF will provide more active sites for glucose electrooxidation,and thus enhance the electrocatalytic performance significantly.As a result,the glucose fuel cell built with the CoO.@CNF anode containing both CoO and Co_(3)O_(4)delivered a maximum power density of 270μW cm^(-2),which is higher than that of other reported Co_(3)O_(4)based GFCs.This work provides a simple strategy to develop excellent transition metal catalysts for GFCs to expand their applications in portable and wearable energy devices. 展开更多
关键词 Glucose electrooxidation Cobalt oxides Valence modulating Carbon nanofiber Wearable glucose fuel cell
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Unbiased parameter estimation of continuous-time system based on modulating functions with input and output white noises
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作者 贺尚红 李旭宇 《Journal of Central South University》 SCIE EI CAS 2011年第3期773-781,共9页
An efficient unbiased estimation method is proposed for the direct identification of linear continuous-time system with noisy input and output measurements.Using the Gaussian modulating filters,by numerical integratio... An efficient unbiased estimation method is proposed for the direct identification of linear continuous-time system with noisy input and output measurements.Using the Gaussian modulating filters,by numerical integration,an equivalent discrete identification model which is parameterized with continuous-time model parameters is developed,and the parameters can be estimated by the least-squares (LS) algorithm.Even with white noises in input and output measurement data,the LS estimate is biased,and the bias is determined by the variances of noises.According to the asymptotic analysis,the relationship between bias and noise variances is derived.One equation relating to the measurement noise variances is derived through the analysis of the LS errors.Increasing the degree of denominator of the system transfer function by one,an extended model is constructed.By comparing the true value and LS estimates of the parameters between original and extended model,another equation with input and output noise variances is formulated.So,the noise variances are resolved by the set of equations,the LS bias is eliminated and the unbiased estimates of system parameters are obtained.A simulation example by comparing the standard LS with bias eliminating LS algorithm indicates that the proposed algorithm is an efficient method with noisy input and output measurements. 展开更多
关键词 continuous-time system unbiased parameter modulating functions noise
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A PLANAR ANTENNA OF CONDUCTOR MODULATING PERIODIC STRUCTURE
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作者 刘圣民 董天临 余敏 《Journal of Electronics(China)》 1991年第2期147-153,共7页
A novel planar leaky-wave antenna of conductor modulating periodic structure formillimeter wave application is proposed.Using the theory of two-dimensional periodic admittancesurface,theoretical analysis,numerical cal... A novel planar leaky-wave antenna of conductor modulating periodic structure formillimeter wave application is proposed.Using the theory of two-dimensional periodic admittancesurface,theoretical analysis,numerical calculation and experimental study are carried out for thiskind of antenna.A planar antenna of conductor modulating periodic structure is realized in 8mmwave band.It has an aperture area of 90×90mm^2.The measured performances of the antennaare good. 展开更多
关键词 PLANAR ANTENNA PERIODIC STRUCTURE ADMITTANCE SURFACE Conductor modulating
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Boosting oxygen evolution reactivity by modulating electronic structure and honeycomb-like architecture in Ni_(2)P/N,P-codoped carbon hybrids
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作者 Menglei Yuan Yu Sun +8 位作者 Yong Yang Jingxian Zhang Sobia Dipazir Tongkun Zhao Shuwei Li Yongbing Xie He Zhao Zhanjun Liu Guangjin Zhang 《Green Energy & Environment》 SCIE CSCD 2021年第6期866-874,共9页
Oxygen evolution reaction(OER)as the foremost stumbling block to generate cost-effective clean fuels has received extensive attention in recent years.But,it still maintains the challenge to manipulate the geometric an... Oxygen evolution reaction(OER)as the foremost stumbling block to generate cost-effective clean fuels has received extensive attention in recent years.But,it still maintains the challenge to manipulate the geometric and electronic structure during single reaction process under the same conditions.Herein,we report a simple self-template strategy to generate honeycomb-like Ni_(2)P/N,P-C hybrids with preferred electronic architecture.Experiments coupled with theoretical results revealed that the synthesized catalyst has two characteristics:firstly,the unique honeycomb-like morphology not only enables the fully utilization of catalytic active sites but also optimizes the mass/electron transportation pathway,which favor the diffusion of electrolyte to accessible active sites.Secondly,N,P-C substrate,on the one hand,largely contributes the electronic distribution near Fermi level(E_(F))thus boosting its electrical conductivity.On the other hand,the support effect result in the upshift of d-band center and electropositivity of Ni sites,which attenuates the energy barrier for the adsorption of OH~àand the formation of*OOH.In consequence,the optimized Ni_(2)P/N,P-C catalysts feature high electrocatalytic activity towards OER(a low overpotential of 252 m V to achieve10 m A cm^(-2))and 10 h long-term stability,the outstanding performance is comparable to most of transition metal catalysts.This work gives a innovative tactics for contriving original OER electrocatalysts,inspirng deeper understanding of fabricating catalysts by combining theoretical simulation and experiment design. 展开更多
关键词 Oxygen evolution reaction NI2P modulating electronic structure Honeycomb-like architecture
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Signal modulating noise effect in bistable stochastic resonance systems and its analog simulation
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作者 肖方红 闫桂荣 谢世成 《Journal of Central South University of Technology》 EI 2006年第5期595-597,共3页
The effect of signal modulating noise in bistable stochastic resonance systems was studied theoretically and experimentally. A mathematical analysis was made on the bistable stochastic resonance model with small syste... The effect of signal modulating noise in bistable stochastic resonance systems was studied theoretically and experimentally. A mathematical analysis was made on the bistable stochastic resonance model with small system parameters. An analogue circuit was designed to perform the effect. The effect of signal modulating noise was shown in the analog simulation experiment. The analog experiment was conducted for two sinusoidal signals with different frequencies. The results show that there are a sinusoidal component corresponding to the input sinusoidal signal and a noise component presented as a Wiener process corresponding to the input white noise in the system output. By properly selecting system parameters, the effect of signal modulating noise can be manifested in the system output. 展开更多
关键词 signal modulating noise effect bistable system stochastic resonance analog simulation
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Associations between Vaginal Douching Practice and Lower Genital Tract Symptoms and Menstrual Disorders among Young Women: A Search for Risk Modulating Factors
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作者 Christopher E. Ekpenyong Koofreh G. Davies 《Advances in Sexual Medicine》 2013年第4期76-84,共9页
This study assessed the associations between vaginal douching practice and the adverse reproductive tract outcomes, and the risk modulating factors among young women. The data source was a cross-sectional population b... This study assessed the associations between vaginal douching practice and the adverse reproductive tract outcomes, and the risk modulating factors among young women. The data source was a cross-sectional population based sample of 1488 women aged 18-35 years in a university community. Self-administered socio-demographic and female genital hygiene practices questionnaire were used to survey the participants. The overall prevalence of vaginal douching was 79.8%. Pelvic pain, vaginal itching, and vaginal discharge were significantly associated with higher odds for douching. Moreover, participants with menstrual disorders such as menorrhagia, oligomenorrhea, and inter-menstrual bleeding douche more often than those without these disorders. Early-onset, higher-frequency, and prolonged douching, as well as douching with commercial vaginal deodorant and inserting the nozzle of the douching tube inside the vagina were associated with higher rate of pelvic and menstrual disorders. The present study revealed a paradoxical relation between vaginal douching and adverse reproductive tract disorders, which supports the hypothesis of confounding by indication. The direction of the association is dependent on several modifiable and unmodifiable risk factors. 展开更多
关键词 VAGINAL Douching PRACTICE ADVERSE Reproductive Tract Outcome RISK modulating Factor
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Modulating the Lasing Performance of the Quantum Dot-Cavity System by Adding a Resonant Driving Field
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作者 秦利国 王琴 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第1期115-119,共5页
We propose a new scheme on modulating the lasing performance of a quantum dot-cavity system. Compared to the conventional above-band pump, in our new scheme an additional resonant driving field is applied on the quant... We propose a new scheme on modulating the lasing performance of a quantum dot-cavity system. Compared to the conventional above-band pump, in our new scheme an additional resonant driving field is applied on the quantum dot-cavity system. By employing the master equation theory and the Jaynes-Cummings model, we are able to study the interesting phenomenon of the coupling system. To compare the different behaviors between using our new scheme and the conventional method,we carry out investigatioin for both the 'good system'and 'more realistic system', characterizing several important parameters, such as the cavity population, exciton population and the second-order correlation function at zero time delay. Through numerical simulations,we demonstrate that for both the good system and more realistic system, their lasing regimes can be displaced into other regimes in the presence of a resonant driving field. 展开更多
关键词 modulating the Lasing Performance of the Quantum Dot-Cavity System by Adding a Resonant Driving Field
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3-57 Carbon Ion Radiation Inhibits Glioma and Endothelial Cell Migration Through Modulating VEGF
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作者 Liu Yang Yan Jiawei Zhang Hong 《IMP & HIRFL Annual Report》 2015年第1期158-158,共1页
Radiotherapy, a standard adjuvant to surgery, improves survival rates in patients, but resistance to treatment by some gliomas limits the success of clinical application. Emerging evidence indicates that the tumor mic... Radiotherapy, a standard adjuvant to surgery, improves survival rates in patients, but resistance to treatment by some gliomas limits the success of clinical application. Emerging evidence indicates that the tumor microenvironment contributes to radiation resistance by regulating the levels of cytokines and growth factors[1;2]. 展开更多
关键词 MIGRATION THROUGH modulating
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