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Predictive active control of building structures using LQR and artificial intelligence
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作者 Nirmal S.Mehta Vishisht Bhaiya +1 位作者 K.A.Patel Ehsan Noroozinejad Farsangi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期489-502,共14页
This study presents a neural network-based model for predicting linear quadratic regulator(LQR)weighting matrices for achieving a target response reduction.Based on the expected weighting matrices,the LQR algorithm is... This study presents a neural network-based model for predicting linear quadratic regulator(LQR)weighting matrices for achieving a target response reduction.Based on the expected weighting matrices,the LQR algorithm is used to determine the various responses of the structure.The responses are determined by numerically analyzing the governing equation of motion using the state-space approach.For training a neural network,four input parameters are considered:the time history of the ground motion,the percentage reduction in lateral displacement,lateral velocity,and lateral acceleration,Output parameters are LQR weighting matrices.To study the effectiveness of an LQR-based neural network(LQRNN),the actual percentage reduction in the responses obtained from using LQRNN is compared with the target percentage reductions.Furthermore,to investigate the efficacy of an active control system using LQRNN,the controlled responses of a system are compared to the corresponding uncontrolled responses.The trained neural network effectively predicts weighting parameters that can provide a percentage reduction in displacement,velocity,and acceleration close to the target percentage reduction.Based on the simulation study,it can be concluded that significant response reductions are observed in the active-controlled system using LQRNN.Moreover,the LQRNN algorithm can replace conventional LQR control with the use of an active control system. 展开更多
关键词 active control system linear quadratic regulator artificial neural networks state-space approach response effectiveness factor RESILIENCE
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Fuzzy robust path tracking strategy of an active pelagic trawl system with coordinated ship and winch regulation 被引量:2
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作者 陈英龙 周华 +1 位作者 赵勇刚 侯交义 《Journal of Central South University》 SCIE EI CAS 2014年第1期167-179,共13页
A fuzzy robust path tracking strategy of an active pelagic trawl system with ship and winch regulation is proposed.First,nonlinear mathematic model of the pelagic trawl system was derived using Lagrange equation and f... A fuzzy robust path tracking strategy of an active pelagic trawl system with ship and winch regulation is proposed.First,nonlinear mathematic model of the pelagic trawl system was derived using Lagrange equation and further simplified as a low order model for the convenience of controller design.Then,an active path tracking strategy of pelagic trawl system was investigated to improve the catching efficiency of the target fish near the sea bottom.By means of the active tracking control,the pelagic trawl net can be positioned dynamically to follow a specified trajectory via the coordinated winch and ship regulation.In addition,considering the system nonlinearities,modeling uncertainties and the unknown exogenous disturbance of the trawl system model,a nonlinear robust H2 /H∞ controller based on Takagi-Sugeno(T-S) fuzzy model was presented,and the simulation comparison with linear robust H2 /H∞ controller and PID method was conducted for the validation of the nonlinear fuzzy robust controller.The nonlinear simulation results show that the average tracking error is 0.4 m for the fuzzy robust H2 /H∞ control and 125.8 m for the vertical and horizontal displacement,respectively,which is much smaller than linear H2 /H∞ controller and the PID controller.The investigation results illustrate that the fuzzy robust controller is effective for the active path tracking control of the pelagic trawl system. 展开更多
关键词 模糊模型 活动路径 跟踪策略 系统 拖网 远洋 非线性数学模型 监管
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Research Progress of Anti-tumor Effects of Curcuma zedoaria and its Active Ingredients Through Immune Regulation Mechanism
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作者 Zhuli Hou Gang Fang 《Journal of Clinical and Nursing Research》 2021年第4期1-7,共7页
The continuous increase in the incidence rate of various fatal malignant tumors in the recent years warrants an imperative search for medications or drugs with obvious anti-tumor eflects and reliable curative effects.... The continuous increase in the incidence rate of various fatal malignant tumors in the recent years warrants an imperative search for medications or drugs with obvious anti-tumor eflects and reliable curative effects.Previous studies have found that Curcuma zedoaria and its active ingredients,such as turmeric oil,curcumol,and P-elemene,have obvious antitumor effects,and they do not have the adverse reactions and side effects seen in the anti-tumor drugs of Western medicine.Based on the review and inductive analysis of related literature,we summarize in the present article the results of some researchers who investigated the anti-tumor effects of Curcuma zedoaria and its active ingredients through the immune regulation mechanism. 展开更多
关键词 Malignant tumor Curcuma zedoaria and its active ingredients Immune regulation MECHANISM Anti-tumor effect
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Mechanism of active silica nanofluids based on interface-regulated effect during spontaneous imbibition 被引量:2
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作者 Xu-Guang Song Ming-Wei Zhao +2 位作者 Cai-Li Dai Xin-Ke Wang Wen-Jiao Lv 《Petroleum Science》 SCIE CAS CSCD 2021年第3期883-894,共12页
The ultra-low permeability reservoir is regarded as an important energy source for oil and gas resource development and is attracting more and more attention.In this work,the active silica nanofuids were prepared by m... The ultra-low permeability reservoir is regarded as an important energy source for oil and gas resource development and is attracting more and more attention.In this work,the active silica nanofuids were prepared by modifed active silica nanoparticles and surfactant BSSB-12.The dispersion stability tests showed that the hydraulic radius of nanofuids was 58.59 nm and the zeta potential was−48.39 mV.The active nanofuids can simultaneously regulate liquid-liquid interface and solid-liquid interface.The nanofuids can reduce the oil/water interfacial tension(IFT)from 23.5 to 6.7 mN/m,and the oil/water/solid contact angle was altered from 42°to 145°.The spontaneous imbibition tests showed that the oil recovery of 0.1 wt%active nanofuids was 20.5%and 8.5%higher than that of 3 wt%NaCl solution and 0.1 wt%BSSB-12 solution.Finally,the efects of nanofuids on dynamic contact angle,dynamic interfacial tension and moduli were studied from the adsorption behavior of nanofuids at solid-liquid and liquid-liquid interface.The oil detaching and transporting are completed by synergistic efect of wettability alteration and interfacial tension reduction.The fndings of this study can help in better understanding of active nanofuids for EOR in ultra-low permeability reservoirs. 展开更多
关键词 active nanofuids regulate interface Ultra-low permeability Spontaneous imbibition
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The Effect of Plant Growth Regulator and Active Charcoal on the Development of Microtubers of Potatoes 被引量:1
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作者 Maolin Peng Xiyao Wang Liqin Li 《American Journal of Plant Sciences》 2012年第11期1535-1540,共6页
With the detoxicated seedling of a potato cultivation breed named “Mire” as the material, the effect of auxins CCC, 6-BA, and active carbon to microtubers of potato (Solanum tubersum L.) was investigated under the i... With the detoxicated seedling of a potato cultivation breed named “Mire” as the material, the effect of auxins CCC, 6-BA, and active carbon to microtubers of potato (Solanum tubersum L.) was investigated under the in-vitro circumstances. The result indicated the exogenous auxins improved the production and quality of microtubers of potatoes. The effect of induction can be described as CCC > CCC + 6-BA > 6-BA > CK, the number of microtubers in per flask is 8.17 > 7.67 > 7.29 > 5.46, and the number of large potatoes in per flask is 6.33 > 5.17 > 3.17 > 1. In addition, by adding 0.5‰ of active charcoal, the growth period was shortened from 25.0 days to 9.33 days on average, and the amount of larger potatoes increased 8.54%. These results benefited the growth of microtubers of potato. 展开更多
关键词 PLANT Growth regulATORS active Charcoal MICROTUBERS of POTATO
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Novel Synthesis, Crystal Structure, and Plant-growth Regulation Activity of(1S,4R)-4,7,7-Trimethyl-6-oxabicyclo[3.2.1]octane-1,4-diol
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作者 黄道战 谢志鹏 蓝虹云 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第5期741-746,共6页
The title compound,(1S,4R)-4,7,7-trimethyl-6-oxabicyclo [3.2.1] octane-1,4-diol(C(10)H(18)O3), has been synthesized from terpinolene via one-step catalytic synthetic method and structurally characterized by me... The title compound,(1S,4R)-4,7,7-trimethyl-6-oxabicyclo [3.2.1] octane-1,4-diol(C(10)H(18)O3), has been synthesized from terpinolene via one-step catalytic synthetic method and structurally characterized by means of HRMS, IR, 1H-NMR, (13)C-NMR and single-crystal X-ray diffraction. The compound crystallizes in trigonal, space group R-3, with a = 27.892(9), b = 27.892(9), c = 6.720(2) A, γ = 120°, Z = 18, V = 4527(3) A3, Dc = 1.230 g/cm3, Mr = 186.24, λ(Mo Kα) = 0.71073?, μ = 0.09 mm(-1), F(000) = 1836, the final R = 0.051 and wR = 0.161. The title compound molecule contained a 6-oxabicyclo[3.2.1]octane skeleton and two hydroxyl groups, which were connected through intermolecular O–H…O hydrogen bonds to generate a two-dimensional network. Especially, the preliminary bioassay showed that the title compound can promote the root growth and shoot elongation of rape(Brassica campestris) at low concentration(0.62570 mmol·L^-1) and inhibit them at high concentration(〉 70 mmol·L^-1). 展开更多
关键词 monoterpene oxybicyclodiol one-step catalytic synthesis crystal structure plant-growth regulation activity terpinolene
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Regulation of Cleavage Activity of Ser-His Dipeptide on DNA by Phosphorylation
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作者 Xiang Hong LI Yu Fen ZHAO(Department of Chemistry, Tsinghun University Beijing 100084) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第7期611-612,共2页
The cleavage reactions of Ser-His and its N-terminal phosphorylated form - N-(O,O-diisopropyl) phosphoryl seryl-histidine (DIPP-Ser-His) were studied on DNA. It was found that the phosphorylation of Ser-His caused the... The cleavage reactions of Ser-His and its N-terminal phosphorylated form - N-(O,O-diisopropyl) phosphoryl seryl-histidine (DIPP-Ser-His) were studied on DNA. It was found that the phosphorylation of Ser-His caused the lost of the cleavage activity on DNA. The result might give some clue on the regulation of the activity of protein by phosphorylation. 展开更多
关键词 activITY regulation of Cleavage activity of Ser-His Dipeptide on DNA by Phosphorylation DNA
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DC Motor Speed Regulator via Active Damping Injection and Angular Acceleration Estimation Techniques
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作者 Seok-Kyoon Kim Choon Ki Ahn 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第3期641-647,共7页
This paper suggests a novel model-based nonlinear DC motor speed regulator without the use of a current sensor.The current dynamics,machine parameters and mismatched load variations are considered.The proposed control... This paper suggests a novel model-based nonlinear DC motor speed regulator without the use of a current sensor.The current dynamics,machine parameters and mismatched load variations are considered.The proposed controller is designed to include an active damping term that regulates the motor speed in accordance with the first-order low-pass filter dynamics through the pole-zero cancellation.Meanwhile,the angular acceleration and its reference are obtained from simple first-order estimators using only the speed information.The effectiveness is experimentally verified using hardware comprising the QUBEServo2,myRIO-1900,and LabVIEW. 展开更多
关键词 active damping injection angular acceleration estimator DC motor(DCM) speed regulation
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Regulation of Protein Kinase C on Proliferation and Telomerase Activity of Nasopharyngeal Carcinoma Cell Line CNE-2Z
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作者 Bo BAO Pei-Chun HUANG Chuan-Ren DONG(Department of Pathophysiology, Guangdong Medical College, Zhanjiang 524023,China) 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2005年第S1期59-60,共2页
关键词 CNE CELL regulation of Protein Kinase C on Proliferation and Telomerase activity of Nasopharyngeal Carcinoma Cell Line CNE-2Z activITY
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GPCR/endocytosis/ERK signaling/S2R is involved in the regulation of the internalization,mitochondria-targeting and-activating properties of human salivary histatin 1
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作者 Dandan Ma Wei Sun +6 位作者 Cuicui Fu Kamran Nazmi Enno C.I.Veerman Richard T.Jaspers Jan G.M.Bolscher Floris J.Bikker Gang Wu 《International Journal of Oral Science》 SCIE CAS CSCD 2022年第3期334-348,共15页
Human salivary histatin 1(Hst1)exhibits a series of cell-activating properties,such as promoting cell spreading,migration,and metabolic activity.We recently have shown that fluorescently labeled Hst1(F-Hst1)targets an... Human salivary histatin 1(Hst1)exhibits a series of cell-activating properties,such as promoting cell spreading,migration,and metabolic activity.We recently have shown that fluorescently labeled Hst1(F-Hst1)targets and activates mitochondria,presenting an important molecular mechanism.However,its regulating signaling pathways remain to be elucidated.We investigated the influence of specific inhibitors of G protein-coupled receptors(GPCR),endocytosis pathways,extracellular signal-regulated kinases1/2(ERK1/2)signaling,p38 signaling,mitochondrial respiration and Na+/K+-ATPase activity on the uptake,mitochondria-targeting and-activating properties of F-Hst1.We performed a si RNA knockdown(KD)to assess the effect of Sigma-2 receptor(S2R)/Transmembrane Protein 97(TMEM97)—a recently identified target protein of Hst1.We also adopted live cell imaging to monitor the whole intracellular trafficking process of F-Hst1.Our results showed that the inhibition of cellular respiration hindered the internalization of F-Hst1.The inhibitors of GPCR,ERK1/2,phagocytosis,and clathrin-mediated endocytosis(CME)as well as siRNA KD of S2R/TMEM97 significantly reduced the uptake,which was accompanied by the nullification of the promoting effect of F-Hst1 on cell metabolic activity.Only the inhibitor of CME and KD of S2R/TMEM97 significantly compromised the mitochondria-targeting of Hst1.We further showed the intracellular trafficking and targeting process of F-Hst1,in which early endosome plays an important role.Overall,phagocytosis,CME,GPCR,ERK signaling,and S2R/TMEM97 are involved in the internalization of Hst1,while only CME and S2R/TMEM97 are critical for its subcellular targeting.The inhibition of either internalization or mitochondria-targeting of Hst1 could significantly compromise its mitochondria-activating property. 展开更多
关键词 GPCR/endocytosis/ERK signaling/S2R is involved in the regulation of the internalization mitochondria-targeting and activating properties of human salivary histatin 1 ERK
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Activity regulation and applications of metal-organic framework-based nanozymes
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作者 Ge Fang Shou-Xin Bao +1 位作者 Gen-Xiu Zhou Cui-Cui Ge 《Rare Metals》 SCIE EI CAS CSCD 2024年第3期900-914,共15页
As a new generation of artificial enzymes,nanozymes show outstanding advantages such as high stability,low cost,and facile synthesis,which endow them with promising applications in biomedical and environmental fields.... As a new generation of artificial enzymes,nanozymes show outstanding advantages such as high stability,low cost,and facile synthesis,which endow them with promising applications in biomedical and environmental fields.Among the various reported nanozymes,metal-organic frameworks(MOFs)could mimic the active center of natural enzymes and provide a hydrophobic environment,which makes MOFs attractive alternatives to natural enzymes.Owing to the highly structural diversity and tailorability of MOFs,rational design will contribute to improve the activity of MOF-based nanozymes and promote their potential applications in both biomedical and environmental fields.Therefore,a comprehensiye suminary of activity regulatory strategies of MOF-based nanozymes is urgently needed.Firstly,we summarized the activity regulatory strategies of MOFs with intrinsic enzyme-like activities via modulation of metal nodes,ligands,structures and morphologies.Then the applications of MOF-based nanozymes in biosensing,hazardous degradation,antibacterial,and cancer therapy were also introduced.Finally,the current challenges and future perspectives were discussed in depth.It is highly expected that this review will provide a better understanding on the rational design of novel high-performance MOF-based nanozymes. 展开更多
关键词 Metal-organic frameworks(MOF)-based nanozymes activity regulation BIOSENSING Cancer therapy Hazardous degradation ANTIBACTERIAL
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A Review on Self-Recovery Regulation(SR)Technique for Unbalance Vibration of High-End Equipment 被引量:10
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作者 Xin Pan Jiaqiao Lu +2 位作者 Jiaji Huo Jinji Gao Haiqi Wu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第6期1-23,共23页
The high-end equipment represented by high-end machine tools and aero-engines is the core component of the national intelligent manufacturing plan,and the mass unbalance is the main reason for its excessive vibration,... The high-end equipment represented by high-end machine tools and aero-engines is the core component of the national intelligent manufacturing plan,and the mass unbalance is the main reason for its excessive vibration,that seriously impacts the operation efficiency and running life of the equipment.In order to change the traditional way that the fault of equipment can only be repaired by human,the self-recovery mechanism of human and animal are given to the equipment in this paper,which forms the self-recovery regulation(SR)system for unbalance vibration of high-end equipment.The system can online generate the self-recovery force to restrain the unbalance vibration of the equipment in operation,which is an important direction for the development of the equipment to the advanced intelligent stage.Based on the basic principles of SR technique,the typical engineering application cases of this technique in the field of aeroengine and high-end machine tools are introduced,and four related studies promoting the development of this technique are summarized and analyzed in turn.It includes feature extraction,imbalance location,regulation method and balancing actuator.Self-recovery Regulation(SR)Technique is an important way to realize intelligent manufacturing and intelligent maintenance.Relevant research can lay a technical foundation for the development of high-end equipment with self-health function. 展开更多
关键词 Unbalance vibration Self-recovery regulation active balancing High-end equipment Self-health
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Physiological roles of mitogen-activated-protein-kinase-activated p38-regulated/activated protein kinase 被引量:8
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作者 Sergiy Kostenko Gianina Dumitriu +1 位作者 Kari Jenssen Lgreid Ugo Moens 《World Journal of Biological Chemistry》 CAS 2011年第5期73-89,共17页
Mitogen-activated protein kinases(MAPKs)are a family of proteins that constitute signaling pathways involved in processes that control gene expression,cell division, cell survival,apoptosis,metabolism,differentiation ... Mitogen-activated protein kinases(MAPKs)are a family of proteins that constitute signaling pathways involved in processes that control gene expression,cell division, cell survival,apoptosis,metabolism,differentiation and motility.The MAPK pathways can be divided into conventional and atypical MAPK pathways.The first group converts a signal into a cellular response through a relay of three consecutive phosphorylation events exerted by MAPK kinase kinases,MAPK kinase,and MAPK.Atypical MAPK pathways are not organized into this three-tiered cascade.MAPK that belongs to both conventional and atypical MAPK pathways can phosphorylate both non-protein kinase substrates and other protein kinases.The latter are referred to as MAPK-activated protein kinases.This review focuses on one such MAPK-activated protein kinase,MAPK-activated protein kinase 5(MK5)or p38-regulated/activated protein kinase(PRAK).This protein is highly conserved throughout the animal kingdom and seems to be the target of both conventional and atypical MAPK pathways.Recent findings on the regulation of the activity and subcellular localization,bona fide interaction partners and physiological roles of MK5/PRAK are discussed. 展开更多
关键词 MITOGEN-activATED PROTEIN KINASE p38- regulated/activated PROTEIN KINASE Extracellular signalregulated KINASE PROTEIN KINASE A SUBCELLULAR localization Phosphorylation PROTEIN interaction
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探测应答调控蛋白PhoBNF20D自由态中存在的Pre-Active构象 被引量:2
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作者 寇新慧 刘乙祥 +3 位作者 刘兴弘 李从刚 刘买利 姜凌 《波谱学杂志》 CAS 北大核心 2019年第2期164-171,共8页
PhoB是PhoR/PhoB双组分信号转导系统(TCS)中的应答调控蛋白,来自大肠杆菌,可以参与环境中自由Pi的调控应答.PhoB拥有保守的磷酸化位点D53,当Mg^2+存在时,会变成活性构象,但是其中的机理尚不清楚.目前已经有报道指出,自由态的应答调控蛋... PhoB是PhoR/PhoB双组分信号转导系统(TCS)中的应答调控蛋白,来自大肠杆菌,可以参与环境中自由Pi的调控应答.PhoB拥有保守的磷酸化位点D53,当Mg^2+存在时,会变成活性构象,但是其中的机理尚不清楚.目前已经有报道指出,自由态的应答调控蛋白存在少量的活性构象,而且它们和蛋白的激活过程相关,但是这种活性构象一般不稳定,很难观测到.本文以PhoBN^F20D作为模型,1H-15NHSQC和19F NMR谱图显示,自由态PhoBN^F20D在溶液中存在pre-active构象,BeF3^-可以稳定这种活性构象,而且Mg^2+可以促进非活性构象到活性构象之间的转化,在BeF3^-存在的情况下可以使PhoBN^F20D形成完全的活性构象.同时我们利用Carr-Purcell-Meiboom-Gill(CPMG)弛豫弥散实验证明了PhoBN^F20D存在两态交换. 展开更多
关键词 BeF3^- 活性构象 核磁共振(NMR) 应答调控蛋白 双组分信号转导系统(TCS)
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SHP2 regulates skeletal cell fate by modifying SOX9 expression and transcriptional activity 被引量:3
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作者 Chunlin Zuo Lijun Wang +11 位作者 Raghavendra M.Kamalesh Margot E.Bowen Douglas C.Moore Mark S.Dooner Anthony M.Reginato Qian Wu Christoph Schorl Yueming Song Matthew L.Warman Benjamin G.Neel Michael G.Ehrlich Wentian Yang 《Bone Research》 CAS CSCD 2018年第2期132-144,共13页
Chondrocytes and osteoblasts differentiate from a common mesenchymal precursor, the osteochondroprogenitor(OCP), and help build the vertebrate skeleton. The signaling pathways that control lineage commitment for OCP... Chondrocytes and osteoblasts differentiate from a common mesenchymal precursor, the osteochondroprogenitor(OCP), and help build the vertebrate skeleton. The signaling pathways that control lineage commitment for OCPs are incompletely understood. We asked whether the ubiquitously expressed protein-tyrosine phosphatase SHP2(encoded by Ptpn11) affects skeletal lineage commitment by conditionally deleting Ptpn11 in mouse limb and head mesenchyme using "Cre-lox P"-mediated gene excision.SHP2-deficient mice have increased cartilage mass and deficient ossification, suggesting that SHP2-deficient OCPs become chondrocytes and not osteoblasts. Consistent with these observations, the expression of the master chondrogenic transcription factor SOX9 and its target genes Acan, Col2a1, and Col10a1 were increased in SHP2-deficient chondrocytes, as revealed by gene expression arrays, q RT-PCR, in situ hybridization, and immunostaining. Mechanistic studies demonstrate that SHP2 regulates OCP fate determination via the phosphorylation and SUMOylation of SOX9, mediated at least in part via the PKA signaling pathway. Our data indicate that SHP2 is critical for skeletal cell lineage differentiation and could thus be a pharmacologic target for bone and cartilage regeneration. 展开更多
关键词 SHP2 regulates skeletal cell modifying SOX9 expression transcriptional activity SOX
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Magnolol protects against acute gastrointestinal injury in sepsis by down-regulating regulated on activation,normal T-cell expressed and secreted 被引量:7
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作者 Shi-Hao Mao Dan-Dan Feng +5 位作者 Xi Wang Yi-Hui Zhi Shu Lei Xi Xing Rong-Lin Jiang Jian-Nong Wu 《World Journal of Clinical Cases》 SCIE 2021年第34期10451-10463,共13页
BACKGROUND Sepsis is a major medical challenge.Magnolol is an active constituent of Houpu that improves tissue function and exerts strong anti-endotoxin and anti-inflammatory effects,but the mechanism by which it redu... BACKGROUND Sepsis is a major medical challenge.Magnolol is an active constituent of Houpu that improves tissue function and exerts strong anti-endotoxin and anti-inflammatory effects,but the mechanism by which it reduces intestinal inflammation in sepsis is yet unclear.AIM To assess the protective effect of magnolol on intestinal mucosal epithelial cells in sepsis and elucidate the underlying mechanisms.METHODS Enzyme-linked immunosorbent assay was used to measure tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),IL-6,and regulated on activation,normal T-cell expressed and secreted(RANTES)levels in serum and ileal tissue in animal studies.The histopathological changes of the ileal mucosa in different groups were observed under a microscope.Cell Counting Kit-8 and cell permeability assays were used to determine the concentration of drug-containing serum that did not affect the activity of Caco2 cells but inhibited lipopolysaccharide(LPS)-induced decrease in permeability.Immunofluorescence and Western blot assays were used to detect the levels of RANTES,inhibitor of nuclear factor kappa-B kinaseβ(IKKβ),phosphorylated IKKβ(p-IKKβ),inhibitor of nuclear factor kappa-B kinaseα(IκBα),p65,and p-p65 proteins in different groups in vitro.RESULTS In rats treated with LPS by intravenous tail injection in the presence or absence of magnolol,magnolol inhibited the expression of proinflammatory cytokines,IL-1β,IL-6,and TNF-αin a dose-dependent manner.In addition,magnolol suppressed the production of RANTES in LPS-stimulated sepsis rats.Moreover,in vitro studies suggested that magnolol inhibited the increase of p65 nucleation,thereby markedly downregulating the production of the phosphorylated form of IKKβin LPS-treated Caco2 cells.Specifically,magnolol inhibited the translocation of the transcription factor nuclear factor-kappa B(NF-κB)from the cytosol into the nucleus and down-regulated the expression level of the chemokine RANTES in LPS-stimulated Caco2 cells.CONCLUSION Magnolol down-regulates RANTES levels by inhibiting the LPS/NF-κB signaling pathways,thereby suppressing IL-1β,IL-6,and TNF-αexpression to alleviate the mucosal barrier dysfunction in sepsis. 展开更多
关键词 SEPSIS MAGNOLOL regulated on activation normal T-cell expressed and secreted Anti-inflammation Lipopolysaccharide Nuclear factor-kappa B
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Enhancement of oxygen reduction activity and stability via introducing acid-resistant refractory Mo and regulating the near-surface Pt content 被引量:2
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作者 Shouquan Feng Jiajia Lu +5 位作者 Lin Luo Guangfu Qian Jinli Chen Hanna SAbbo Salam JJTitinchi Shibin Yin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第12期246-252,共7页
Although Pt Ni catalyst possesses good oxygen reduction activity, its poor stability is the main obstacle for the commercialization of proton exchange membrane fuel cells(PEMFCs). In this work, we introduce the acid-r... Although Pt Ni catalyst possesses good oxygen reduction activity, its poor stability is the main obstacle for the commercialization of proton exchange membrane fuel cells(PEMFCs). In this work, we introduce the acid-resistant refractory Mo to enhance the structure stability and modify the electronic structure of Pt in the prepared PtNi catalyst, improving the catalytic activity for oxygen reduction reaction(ORR). In addition, near-surface Pt content in the nanoparticle is also optimized to balance the ORR activity and stability. The electrochemical results show that the alloy formed by Mo and Pt Ni is obviously more stable than the PtNi alloy alone, because the acid-resistant Mo and its oxides effectively prevent the dissolution of Pt. Especially, the Pt3 Ni3 MoN/C exhibits the optimal ORR catalytic performance in O2-saturated 0.1 mol L^(-1) HClO4 aqueous solutions, with mass activity(MA) of 900 m A mg^(-1) Pt at 0.90 V vs. RHE, which is 3.75 times enhancement compared with the commercial Pt/C(240 mA mg^(-1) Pt). After 30 k accelerated durability tests, its MA(690 m A mg^(-1) Pt) is still 2.88 times higher than the pristine Pt/C. This study thus provides a valuable method to design stable ORR catalysts with high efficiency and has great significance for the commercialization of PEMFCs. 展开更多
关键词 Oxygen reduction reaction Surface platinum content regulate Ternary alloy catalyst activITY STABILITY
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Role of mitochondria in regulating micro RNA activity and its relevance to the central nervous system 被引量:2
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作者 Wang-Xia Wang Joe E.Springer 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第7期1026-1028,共3页
Mitochondria serve as the powerhouse of cells,respond to cellular demands and stressors,and play an essential role in cell signaling,differentiation,and survival.Aberrant mitochondria function has been linked to diver... Mitochondria serve as the powerhouse of cells,respond to cellular demands and stressors,and play an essential role in cell signaling,differentiation,and survival.Aberrant mitochondria function has been linked to diverse and complex human diseases such as neurodegenerative diseases,cancers,myopathies,premature aging,and metabolic syndromes(Nunnari and Suomalainen,2012). 展开更多
关键词 RNA Role of mitochondria in regulating micro RNA activity and its relevance to the central nervous system gene
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Effect of IL-4 on altered expression of complement activation regulators in rat pancreatic cells during severe acute pancreatitis 被引量:14
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作者 Cheng Zhang Chun-Lin Ge Ren-Xuan Guo San-Guang He 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第43期6770-6774,共5页
AIM: To investigate the effect of IL-4 on the altered expression of complement activation regulators in pancreas and pancreatic necrosis during experimental severe acute pancreatitis (SAP).METHODS: SAP model of rats w... AIM: To investigate the effect of IL-4 on the altered expression of complement activation regulators in pancreas and pancreatic necrosis during experimental severe acute pancreatitis (SAP).METHODS: SAP model of rats was established by retrograde injection of 5% sodium taurocholate (1 mL/kg)into the pancreatic duct. We immunohistochemically assayed the expression of three complement activation regulators: decay accelerating factor (DAF; CD55), 20ku homologous restriction factor (HRF20; CD59) and membrane cofactor protein (MCP; CD46), in the pancreatic acinar cells of rats at 0, 3, 6, 12, and 24 h after the induction of SAP model. Meanwhile the levels of amylase and lipase were determined, and morphological examination was performed. Then, 61 rats were randomly divided into three groups. Group A (n = 21) received notreatment after the SAP model was established; group B (n = 20) was given IL-4 (8 μg/animal) intraperitoneally 0.5 h before the SAP model was established; group C (n = 20) was given IL-4 (8 μg/animal) intraperitoneally 0.5 h after the SAP model was established. Plasma amylase and lipase, extent of pancreatic necrosis and expression of complement activation regulators were investigated 6 h after the induction of SAP model.RESULTS: Three complement activation regulators were all expressed in pancreatic acinar cells. MCP was not found on the basolateral surface as reported. Contrary to the gradually increasing plasma level of amylase and lipase, expression of complement activation regulators decreased after SAP model was set up. At the same time, the severity of pancreatic necrosis was enhanced.A strong negative correlation was found between the expression of MCP, DAF, CD59 in pancreatic acinar cells and the severity of pancreatic necrosis (r = -0.748, -0.827,-0.723; P<0.01). In the second series of experiments,no matter when the treatment of IL-4 was given (before or after the induction of SAP model), the serum level of amylase or lipase Was decreased and the extent of pancreatic necrosis was ameliorated significantly. Compared to SAP control group, the expression of DAF and CD59in pancreas was reinforced when IL-4 was given before the induction of SAP model (P<0.01, P<0.05), but the expression of MCP was not influenced (P>0.05). The expression of DAF was enhanced, when IL-4 was given after the induction of SAP model (P<0.05), but the expression of CD59 and MCP did not change (P>0.05).CONCLUSION: Complement activation regulators may participate in the pathogenesis of pancreatic inflammation. Downregulation of complement activation regulators expression may be one of the causes of pancreatic necrosis. IL-4 treatment may control SAP aggravation by enhancing expression of DAF and CD59 in pancreas and decreasingpancreaticnecrosis. Moreover, DAF and CD59may play an important role in the regulation of complement activation regulators during SAP. 展开更多
关键词 IL-4 基因表达 活化作用 胰腺炎
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Expression and regulation of IL-22 in the IL-17.producing CD4+T lymphocytes 被引量:20
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作者 Yeonseok Chung Xuexian Yang +3 位作者 Seon Hee Chang Li Ma Qiang Tian Chen Dong 《Cell Research》 SCIE CAS CSCD 2006年第11期902-907,共6页
IL-22 是在工作对感染支持纸巾的天生的免疫的 IL-10 家庭的新奇 cytokine。尽管 CD4+ 助手 T 淋巴细胞(TH ) 作为 IL-22 的来源被发现,这 cytokine 的规定糟糕被理解。这里,我们证明 IL-22 被也做 IL-17 的 TH 房间的一个新奇子集在 ... IL-22 是在工作对感染支持纸巾的天生的免疫的 IL-10 家庭的新奇 cytokine。尽管 CD4+ 助手 T 淋巴细胞(TH ) 作为 IL-22 的来源被发现,这 cytokine 的规定糟糕被理解。这里,我们证明 IL-22 被也做 IL-17 的 TH 房间的一个新奇子集在 mRNA 和蛋白质层次表示。IL-22 和 IL-17 被发现被即时 PCR 以及 ELISA 分析被 TGFbeta 和 IL-6 并列地在 TH 区别期间调整。然而, IL-22 不调整 TH 区别;外长的 IL-22 或一个 IL-22 对手没在 TH 区别上有效果。这些数据表明 IL-17-producing T 房间表示的新奇 cytokine,并且建议在组织发炎和自体免疫的疾病表明小径的 IL-22 和 IL-17 的相互作用和协同作用。 展开更多
关键词 IL-22 IL-17 基因表达 T淋巴细胞
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