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Effects of interleukin-10 treated macrophages on bone marrow mesenchymal stem cells via signal transducer and activator of transcription 3 pathway
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作者 Meng-Hao Lyu Ce Bian +3 位作者 Yi-Ping Dou Kang Gao Jun-Ji Xu Pan Ma 《World Journal of Stem Cells》 SCIE 2024年第5期560-574,共15页
BACKGROUND Alveolar bone defects caused by inflammation are an urgent issue in oral implant surgery that must be solved.Regulating the various phenotypes of macrophages to enhance the inflammatory environment can sign... BACKGROUND Alveolar bone defects caused by inflammation are an urgent issue in oral implant surgery that must be solved.Regulating the various phenotypes of macrophages to enhance the inflammatory environment can significantly affect the progression of diseases and tissue engineering repair process.AIM To assess the influence of interleukin-10(IL-10)on the osteogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)following their interaction with macrophages in an inflammatory environment.METHODS IL-10 modulates the differentiation of peritoneal macrophages in Wistar rats in an inflammatory environment.In this study,we investigated its impact on the proliferation,migration,and osteogenesis of BMSCs.The expression levels of signal transducer and activator of transcription 3(STAT3)and its activated form,phos-phorylated-STAT3,were examined in IL-10-stimulated macrophages.Subsequently,a specific STAT3 signaling inhibitor was used to impede STAT3 signal activation to further investigate the role of STAT3 signaling.RESULTS IL-10-stimulated macrophages underwent polarization to the M2 type through substitution,and these M2 macrophages actively facilitated the osteogenic differentiation of BMSCs.Mechanistically,STAT3 signaling plays a crucial role in the process by which IL-10 influences macrophages.Specifically,IL-10 stimulated the activation of the STAT3 signaling pathway and reduced the macrophage inflammatory response,as evidenced by its diminished impact on the osteogenic differentiation of BMSCs.CONCLUSION Stimulating macrophages with IL-10 proved effective in improving the inflammatory environment and promoting the osteogenic differentiation of BMSCs.The IL-10/STAT3 signaling pathway has emerged as a key regulator in the macrophage-mediated control of BMSCs’osteogenic differentiation. 展开更多
关键词 MACROPHAGES INTERLEUKIN-10 Bone marrow mesenchymal stem cells Signal transducer and activator of transcription 3 Inflammatory response
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传感器在生物医学领域研究的前沿进展--TRANSDUCERS 2023国际会议综述
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作者 王耀正 张海霞 《太赫兹科学与电子信息学报》 2023年第7期959-964,共6页
2023年6月25日至6月29日,第22届国际固态传感器、执行器和微系统会议(TRANSDUCERS 2023)在日本京都召开,来自世界各地的专家学者济济一堂,分享在传感器与执行器等领域的最新研究成果。本文从可穿戴生物传感器、生物传感器后端电路和传... 2023年6月25日至6月29日,第22届国际固态传感器、执行器和微系统会议(TRANSDUCERS 2023)在日本京都召开,来自世界各地的专家学者济济一堂,分享在传感器与执行器等领域的最新研究成果。本文从可穿戴生物传感器、生物传感器后端电路和传感器在生物医学领域的应用等3个角度,详细介绍并阐述本次会议上的前沿研究成果,并对相关研究成果的研究意义与未来展望给出了总结。 展开更多
关键词 transducerS 2023 MEMS BIOMEMS 生物医学
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Photoacoustic microscopy based on transparent piezoelectric ultrasound transducers
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作者 Hangbing Peng Zhongwen Cheng +1 位作者 Lvming Zeng Xuanrong Ji 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2023年第5期77-92,共16页
Photoacoustic microscopy(PAM),due to its deep penetration depth and high contrast,is playing an increasingly important role in biomedical imaging.PAM imaging systems equipped with conventional ultrasound transducers h... Photoacoustic microscopy(PAM),due to its deep penetration depth and high contrast,is playing an increasingly important role in biomedical imaging.PAM imaging systems equipped with conventional ultrasound transducers have demonstrated excellent imaging performance.However,these opaque ultrasonic transducers bring some constraints to the further development and application of PAM,such as complex optical path,bulky size,and difficult to integrate with other modalities.To overcome these problems,ultrasonic transducers with high optical transparency have appeared.At present,transparent ultrasonic transducers are divided into optical-based and acoustic-based sensors.In this paper,we mainly describe the acoustic-based piezoelectric transparent transducers in detail,of which the research advances in PAM applications are reviewed.In addition,the potential challenges and developments of transparent transducers in PAM are also demonstrated. 展开更多
关键词 Photoacoustic microscopy transparent ultrasound transducer LiNbO_(3) PMN-PT PVDF CMUT
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Helical particle manipulation based on power-exponent-phase acoustic vortices generated by a sector transducer array
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作者 王青东 胡彦涛 +1 位作者 王胜利 李洪宇 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期333-341,共9页
The characteristics of traditional acoustic vortices(AVs) were verified by the cross-sectional axisymmetric pressure distributions with perfect phase spirals around the center pressure null. In order to generate a non... The characteristics of traditional acoustic vortices(AVs) were verified by the cross-sectional axisymmetric pressure distributions with perfect phase spirals around the center pressure null. In order to generate a non-axisymmetric pressure distribution, the concept of power-exponent-phase was first introduced into the formation of AV beams, named “powerexponent-phase acoustic vortices(PAVs)” in this paper. Based on a ring-array of sector transducers, the helical distribution of the low-pressure valley in cross-sections of PAVs, which enables particles to move from a distant position to the center low-potential well along a certain spiral passageway, was proved theoretically. The particle manipulation behavior for PAVs with a power order of 2 is numerically modeled and experimentally confirmed. The results show that PAVs with a nonaxisymmetric spiral pressure distribution can be used to realize the directional transport of particles in an enlarged scope,suggesting prospective application potential in biomedical engineering. 展开更多
关键词 acoustic vortices power-exponent-phase spiral potential well sector transducer array particle manipulation
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Inverse design and realization of an optical cavity-based displacement transducer with arbitrary responses
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作者 Qianbo Lu Qingxiong Xiao +6 位作者 Chengxiu Liu Yinan Wang Qixuan Zhu Manzhang Xu Xuewen Wang Xiaoxu Wang Wei Huang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第3期12-24,共13页
Optical cavity has long been critical for a variety of applications ranging from precise measurement to spectral analysis.A number of theories and methods have been successful in describing the optical response of a s... Optical cavity has long been critical for a variety of applications ranging from precise measurement to spectral analysis.A number of theories and methods have been successful in describing the optical response of a stratified optical cavity,while the inverse problem,especially the inverse design of a displacement sensitive cavity,remains a significant challenge due to the cost of computation and comprehensive performance requirements.This paper reports a novel inverse design methodology combining the characteristic matrix method,mixed-discrete variables optimization algorithm,and Monte Carlo method-based tolerance analysis.The material characteristics are indexed to enable the mixed-discrete variables optimization,which yields considerable speed and efficiency improvements.This method allows arbitrary response adjustment with technical feasibility and gives a glimpse into the analytical characterization of the optical response.Two entirely different light-displacement responses,including an asymmetric sawtooth-like response and a highly symmetric response,are dug out and experimentally achieved,which fully confirms the validity of the method.The compact Fabry-Perot cavities have a good balance between performance and feasibility,making them promising candidates for displacement transducers.More importantly,the proposed inverse design paves the way for a universal design of optical cavities,or even nanophotonic devices. 展开更多
关键词 inverse design optical cavity displacement transducer mixed-discrete variables optimization stratified system
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Design and analysis of longitudinal–flexural hybrid transducer for ultrasonic peen forming
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作者 Wuqin Li Yongyong Zhu +4 位作者 Xiaolong Lu Huafeng Li Ying Wei Pengwei Shang Bo Feng 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2023年第4期30-39,共10页
Ultrasonic peen forming(UPF)is an emerging technology that exhibits great superiority in both its flexible operating modes and the deep residual stress that it produces compared with conventional plastic forming metho... Ultrasonic peen forming(UPF)is an emerging technology that exhibits great superiority in both its flexible operating modes and the deep residual stress that it produces compared with conventional plastic forming methods.Although ultrasonic transducers with longitudinal vibration have been widely studied,they have seldom been incorporated into UPF devices for machining in confined spaces.To meet the requirements of this type of machining,a sandwich-type piezoelectric transducer with coupled longitudinal-flexural vibrational modes is proposed.The basic structure of the transducer is designed to obtain large vibrational amplitudes in both modes.Experimental results obtained with a prototype device demonstrate the feasibility of the proposed transducer.The measured vibrational amplitude for the working face in the longitudinal vibrational mode is 1.0μm,and electrical matching increases this amplitude by 40%.The flexural vibration characteristics of the same prototype transducer are also tested and are found to be slightly smaller than those of longitudinal mode.The resultant working strokes of the UPF impact pins reach 1.7 mm and 1.2 mm in the longitudinal and flexural modes,respectively.The forming capability of the prototype has been evaluated via 15-min machining on standard 2024-T351 aluminum plates.After UPF,an improved surface morphology with lower surface roughness is obtained.The aluminum plate test piece has an apparent upper deformation with an arc height of 0.64 mm.The measured peak value of the compressive residual stress is around 250 MPa,appearing at a depth of 100μm.The proposed longitudinal-flexural hybrid transducer thus provides a high-performance tool for plate peen forming in confined spaces. 展开更多
关键词 Ultrasonic peen forming Piezoelectric transducer Longitudinal-flexural vibrational mode Modal analysis
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18β-glycyrrhetinic acid promotes gastric cancer cell autophagy and inhibits proliferation by regulating miR-328-3p/signal transducer and activator of transcription 3
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作者 Yi Yang Yi Nan +7 位作者 Yu-Hua Du Shi-Cong Huang Dou-Dou Lu Jun-Fei Zhang Xia Li Yan Chen Lei Zhang Ling Yuan 《World Journal of Gastroenterology》 SCIE CAS 2023年第27期4317-4333,共17页
BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GR... BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GRA)has a variety of pharmacological effects.The aim of this study was to explore the effective target of 18β-GRA in the treatment of GC,in order to provide effective ideas for the clinical prevention and treatment of GC.AIM To investigate the mechanism of 18β-GRA in inhibiting cell proliferation and promoting autophagy flux in GC cells.METHODS Whole transcriptomic analyses were used to analyze and screen differentially expressed microRNAs(miRNAs)in GC cells after 18β-GRA intervention.Lentivirus-transfected GC cells and the Cell Counting Kit-8 were used to detect cell proliferation ability,cell colony formation ability was detected by the clone formation assay,and flow cytometry was used to detect the cell cycle and apoptosis.A nude mouse transplantation tumor model of GC cells was constructed to verify the effect of miR-328-3p overexpression on the tumorigenicity of GC cells.Tumor tissue morphology was observed by hematoxylin and eosin staining,and microtubule-associated protein light chain 3(LC3)expression was detected by immunohistochemistry.TransmiR,STRING,and miRWalk databases were used to predict the relationship between miR-328-3p and signal transducer and activator of transcription 3(STAT3)-related information.Expression of STAT3 mRNA and miR-328-3p was detected by quantitative polymerase chain reaction(qPCR)and the expression levels of STAT3,phosphorylated STAT3(p-STAT3),and LC3 were detected by western blot analysis.The targeted relationship between miR-328-3p and STAT3 was detected using the dual-luciferase reporter gene system.AGS cells were infected with monomeric red fluorescent protein-green fluorescent protein-LC3 adenovirus double label.LC3 was labeled and autophagy flow was observed under a confocal laser microscope.RESULTS The expression of miR-328-3p was significantly upregulated after 18β-GRA intervention in AGS cells(P=4.51E-06).Overexpression of miR-328-3p inhibited GC cell proliferation and colony formation ability,arrested the cell cycle in the G0/G1 phase,promoted cell apoptosis,and inhibited the growth of subcutaneous tumors in BALB/c nude mice(P<0.01).No obvious necrosis was observed in the tumor tissue in the negative control group(no drug intervention or lentivirus transfection)and vector group(the blank vector for lentivirus transfection),and more cells were loose and necrotic in the miR-328-3p group.Bioinformatics tools predicted that miR-328-3p has a targeting relationship with STAT3,and STAT3 was closely related to autophagy markers such as p62.After overexpressing miR-328-3p,the expression level of STAT3 mRNA was significantly decreased(P<0.01)and p-STAT3 was downregulated(P<0.05).The dual-luciferase reporter gene assay showed that the luciferase activity of miR-328-3p and STAT33’untranslated regions of the wild-type reporter vector group was significantly decreased(P<0.001).Overexpressed miR-328-3p combined with bafilomycin A1(Baf A1)was used to detect the expression of LC3 II.Compared with the vector group,the expression level of LC3 II in the overexpressed miR-328-3p group was downregulated(P<0.05),and compared with the Baf A1 group,the expression level of LC3 II in the overexpressed miR-328-3p+Baf A1 group was upregulated(P<0.01).The expression of LC3 II was detected after intervention of 18β-GRA in GC cells,and the results were consistent with the results of miR-328-3p overexpression(P<0.05).Additional studies showed that 18β-GRA promoted autophagy flow by promoting autophagosome synthesis(P<0.001).qPCR showed that the expression of STAT3 mRNA was downregulated after drug intervention(P<0.05).Western blot analysis showed that the expression levels of STAT3 and p-STAT3 were significantly downregulated after drug intervention(P<0.05).CONCLUSION 18β-GRA promotes the synthesis of autophagosomes and inhibits GC cell proliferation by regulating the miR-328-3p/STAT3 signaling pathway. 展开更多
关键词 18β-glycyrrhetinic acid miR-328-3p Signal transducer and activator of transcription 3 Cell proliferation Autophagy flow
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Inner damage identification and residual strength assessment of a 3D printed tunnel with marble-like cementitious materials using piezoelectric transducers
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作者 Guowei Ma Chen Huang Junfei Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期838-851,共14页
Quantitative damage identification of surrounding rock is important to assess the current condition and residual strength of underground tunnels.In this work,an underground tunnel model with marble-like cementitious m... Quantitative damage identification of surrounding rock is important to assess the current condition and residual strength of underground tunnels.In this work,an underground tunnel model with marble-like cementitious materials was first fabricated using the three-dimensional(3D)printing technique and then loaded to simulate its failure mode in the laboratory.Lead zirconate titanate piezoelectric(PZT)transducers were embedded in the surrounding rock around the tunnel in the process of 3D printing.A 3D monitoring network was formed to locate damage areas and evaluate damage extent during loading.Results show that as the load increased,main cracks firstly appeared above the tunnel roof and below the floor,and then they coalesced into the tunnel boundary.Finally,the tunnel model was broken into several parts.The resonant frequency and the peak of the conductance signature firstly shifted rightwards with loading due to the sealing of microcracks,and then shifted backwards after new cracks appeared.An overall increase in the root-mean-square deviation(RMSD)calculated from conductance signatures of all the PZT transducers was observed as the load(damage)increased.Damage-dependent equivalent stiffness parameters(ESPs)were calculated from the real and imaginary signatures of each PZT at different damage states.Satisfactory agreement between equivalent and experimental ESP values was achieved.Also,the relationship between the change of the ESP and the residual strength was obtained.The method paves the way for damage identification and residual strength estimation of other 3D printed structures in civil engineering. 展开更多
关键词 Piezoelectric(PZT)transducers Three-dimensional(3D)printed tunnel Electro-mechanical impedance(EMI) method Equivalent stiffness parameter(ESP) Residual strength
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Combined Digital Electronic Current and Voltage Transducer 被引量:2
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作者 段雄英 邹积岩 +1 位作者 廖敏夫 张可卫 《Journal of Shanghai University(English Edition)》 CAS 2002年第1期79-84,共6页
A high performance current and voltage measurement system has been developed in power system. The system is composed of two parts: one current measurement element and one voltage measurement element. A Rogowski coil ... A high performance current and voltage measurement system has been developed in power system. The system is composed of two parts: one current measurement element and one voltage measurement element. A Rogowski coil and a capacitive voltage divider are used respectively for the line current and voltage measurements. Active electronic components are used to modulate signal, and power supply for these components is drawn from power line via an auxiliary current transformer. Measurement signal is transmitted by optical fibers, which is resistant to electromagnetic induction and noise. With careful design and the use of digital signal processing technology, the whole system can meet 0.5% accuracy for metering and provides large dynamic range coupled with good accuracy for protective relaying use. 展开更多
关键词 electronic current transducer (ECT) electronic voltage transducer (EVT) Rogowski coil capacitive voltage divider (CVD) optical fiber.
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Diffusion-weighted magnetic resonance imaging reflects activation of signal transducer and activator of transcription 3 during focal cerebral ischemia/reperfusion 被引量:1
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作者 Wen-juan Wu Chun-juan Jiang +2 位作者 Zhui-yang Zhang Kai Xu Wei Li 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第7期1124-1130,共7页
Signal transducer and activator of transcription(STAT)is a unique protein family that binds to DNA,coupled with tyrosine phosphorylation signaling pathways,acting as a transcriptional regulator to mediate a variety ... Signal transducer and activator of transcription(STAT)is a unique protein family that binds to DNA,coupled with tyrosine phosphorylation signaling pathways,acting as a transcriptional regulator to mediate a variety of biological effects.Cerebral ischemia and reperfusion can activate STATs signaling pathway,but no studies have confirmed whether STAT activation can be verified by diffusion-weighted magnetic resonance imaging(DWI)in rats after cerebral ischemia/reperfusion.Here,we established a rat model of focal cerebral ischemia injury using the modified Longa method.DWI revealed hyperintensity in parts of the left hemisphere before reperfusion and a low apparent diffusion coefficient.STAT3 protein expression showed no significant change after reperfusion,but phosphorylated STAT3 expression began to increase after 30 minutes of reperfusion and peaked at 24 hours.Pearson correlation analysis showed that STAT3 activation was correlated positively with the relative apparent diffusion coefficient and negatively with the DWI abnormal signal area.These results indicate that DWI is a reliable representation of the infarct area and reflects STAT phosphorylation in rat brain following focal cerebral ischemia/reperfusion. 展开更多
关键词 nerve regeneration cerebral ischemia/repe(fusion magnetic resonance imaging diffusion weighted imaging signal transducer and activator of transcription 3 phosphorylated signal transducer and activator of transcription 3 apparent diffusion coefficient relative apparentdiffusion coefficient IMMUNOHISTOCHEMISTRY western blot assay neural regeneration
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Regulation and function of signal transducer and activator of transcription 3 被引量:20
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作者 Qian-Rong Qi Zeng-Ming Yang 《World Journal of Biological Chemistry》 CAS 2014年第2期231-239,共9页
Signal transducer and activator of transcription 3(STAT3), a member of the STAT family, is a key regulator of many physiological and pathological processes. Significant progress has been made in understanding the tran... Signal transducer and activator of transcription 3(STAT3), a member of the STAT family, is a key regulator of many physiological and pathological processes. Significant progress has been made in understanding the transcriptional control, posttranslational modification, cellular localization and functional regulation of STAT3. STAT3 can translocate into the nucleus and bind to specific promoter sequences, thereby exerting transcriptional regulation. Recent studies have shown that STAT3 can also translocate into mitochondria, participating in aerobic respiration and apoptosis. In addition, STAT3 plays an important role in inflammation and tumorigenesis by regulating cell proliferation, differentiation and metabolism. Conditional knockout mouse models make it possible to study the physiological function of STAT3 in specific tissues and organs. This review summarizes the latest advances in the understanding of the expression, regulation and function of STAT3 in physiological and tumorigenic processes. 展开更多
关键词 SIGNAL transducer and ACTIVATOR of TRANSCRIPTION 3 PHOSPHORYLATION ACETYLATION SIGNAL pathway Tumor
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Signal transducer and activator of transcription 3 promotes the Warburg effect possibly by inducing pyruvate kinase M2 phosphorylation in liver precancerous lesions 被引量:8
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作者 Yang-Hui Bi Wen-Qi Han +4 位作者 Ruo-Fei Li Yun-Jiao Wang Zun-Shu Du Xue-Jiang Wang Ying Jiang 《World Journal of Gastroenterology》 SCIE CAS 2019年第16期1936-1949,共14页
BACKGROUND Study shows that signal transducer and activator of transcription 3(STAT3) can increase the Warburg effect by stimulating hexokinase 2 in breast cancer and upregulate lactate dehydrogenase A and pyruvate de... BACKGROUND Study shows that signal transducer and activator of transcription 3(STAT3) can increase the Warburg effect by stimulating hexokinase 2 in breast cancer and upregulate lactate dehydrogenase A and pyruvate dehydrogenase kinase 1 in myeloma. STAT3 and pyruvate kinase M2(PKM2) can also be activated and enhance the Warburg effect in hepatocellular carcinoma. Precancerous lesions are critical to human and rodent hepatocarcinogenesis. However, the underlying molecular mechanism for the development of liver precancerous lesions remains unknown. We hypothesized that STAT3 promotes the Warburg effect possibly by upregulating p-PKM2 in liver precancerous lesions in rats.AIM To investigate the mechanism of the Warburg effect in liver precancerous lesions in rats.METHODS A model of liver precancerous lesions was established by a modified Solt-Farber method. The liver pathological changes were observed by HE staining and immunohistochemistry. The transformation of WB-F344 cells induced with Nmethyl-N'-nitro-N-nitrosoguanidine and hydrogen peroxide was evaluated by the soft agar assay and aneuploidy. The levels of glucose and lactate in the tissue and culture medium were detected with a spectrophotometer. The protein levels of glutathione S-transferase-π, proliferating cell nuclear antigen(PCNA), STAT3,and PKM2 were examined by Western blot and immunofluorescence.RESULTS We found that the Warburg effect was increased in liver precancerous lesions in rats. PKM2 and p-STAT3 were upregulated in activated oval cells in liverprecancerous lesions in rats. The Warburg effect, p-PKM2, and p-STAT3 expression were also increased in transformed WB-F344 cells. STAT3 activation promoted the clonal formation rate, aneuploidy, alpha-fetoprotein expression,PCNA expression, G1/S phase transition, the Warburg effect, PKM2 phosphorylation, and nuclear translocation in transformed WB-F344 cells.Moreover, the Warburg effect was inhibited by stattic, a specific inhibitor of STAT3, and further reduced in transformed WB-F344 cells after the intervention for PKM2.CONCLUSION The Warburg effect is initiated in liver precancerous lesions in rats. STAT3 activation promotes the Warburg effect by enhancing the phosphorylation of PKM2 in transformed WB-F344 cells. 展开更多
关键词 WARBURG effect Hepatic PROGENITOR cell Signal transducer and activator of transcription 3 PYRUVATE kinase M2 LIVER PRECANCEROUS lesion
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OPTIMAL DESIGN OF A 6-AXIS FORCE TRANSDUCER BASED ON STEWART PLATFORM RELATED TO SENSITIVITY ISOTROPY 被引量:10
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作者 JinZhenlin GaoFenfl GaoFeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第2期146-148,共3页
The design method of a 6-axis force robot's transducer based on the Stewartplatform is detailed. For this purpose, the sensitivity isotropy evaluation criteria of thetransducer are defined, and by the aid of compu... The design method of a 6-axis force robot's transducer based on the Stewartplatform is detailed. For this purpose, the sensitivity isotropy evaluation criteria of thetransducer are defined, and by the aid of computer, the relationships between the criteria and theparameters of all the transducers based on the Stewart platform are investigated within thegeometric model of the solution space, which can provide the theoretical background for the optimalconstruction design of the 6-axis force transducer related to the sensitivity isotropy. 展开更多
关键词 6-axis force robot's transducer optimal construction design stewartplatform sensitivity isotropy
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Excitation and Detection of Shear Horizontal Waves with Electromagnetic Acoustic Transducers for Nondestructive Testing of Plates 被引量:12
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作者 MA Qingzeng JIAO Jingpin +3 位作者 HU Ping ZHONG Xi WU Bin HE Cunfu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第2期428-436,共9页
The fundamental shear horizontal(SH0) wave has several unique features that are attractive for long-range nondestructive testing(NDT). By a careful design of the geometric configuration, electromagnetic acoustic t... The fundamental shear horizontal(SH0) wave has several unique features that are attractive for long-range nondestructive testing(NDT). By a careful design of the geometric configuration, electromagnetic acoustic transducers(EMATs) have the capability to generate a wide range of guided wave modes, such as Lamb waves and shear-horizontal(SH) waves in plates. However, the performance of EMATs is influenced by their parameters. To evaluate the performance of periodic permanent magnet(PPM) EMATs, a distributed-line-source model is developed to calculate the angular acoustic field cross-section in the far-field. Numerical analysis is conducted to investigate the performance of such EMATs with different geometric parameters, such as period and number of magnet arrays, and inner and outer coil widths. Such parameters have a great influence on the directivity of the generated SH0 waves that arises mainly in the amplitude and width of both main and side lobes. According to the numerical analysis, these parameters are optimized to obtain better directivity. Optimized PPM EMATs are designed and used for NDT of strip plates. Experimental results show that the lateral boundary of the strip plate has no perceivable influence on SHO-wave propagation, thus validating their used in NDT. The proposed model predicts the radiation pattern ofPPM EMATs, and can be used for their parameter optimization. 展开更多
关键词 electromagnetic acoustic transducers shear-horizontal waves strip plate nondestructive testing
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Ultrasound Imaging of Pipeline Crack Based on Composite Transducer Array 被引量:7
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作者 Shou-Peng Song Ying-Jie Ni 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第5期25-34,共10页
Cracks, especially small cracks are di cult to be detected in oil and gas transportation pipelines buried underground or covered with layers of material by using the traditional ultrasonic inspection techniques. There... Cracks, especially small cracks are di cult to be detected in oil and gas transportation pipelines buried underground or covered with layers of material by using the traditional ultrasonic inspection techniques. Therefore, a new com?posite ultrasonic transducer array with three acoustic beam incidence modes is developed. The space model of the array is also established to obtain the defect reflection point location. And the crack ultrasound image is thus formed through a series of small cubical elements expanded around the point locations by using the projection of binariza?tion values extracted from the received ultrasonic echo signals. Laboratory experiments are performed on a pipeline sample with di erent types of cracks to verify the e ectiveness and performance of the proposed technique. From the image, the presence of small cracks can be clearly observed, in addition to the sizes and orientations of the cracks. The proposed technique can not only inspect common flaws, but also detect cracks with various orientations, which is helpful for defect evaluation in pipeline testing. 展开更多
关键词 Composite transducer array Ultrasound imaging CRACK NDT&E
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Design of a hexagonal air-coupled capacitive micromachined ultrasonic transducer for air parametric array 被引量:5
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作者 Xiaoli Zhang Hui Zhang Dachao Li 《Nanotechnology and Precision Engineering》 CAS CSCD 2021年第1期26-35,共10页
An air parametric array can generate a highly directional beam of audible sound in air,which has a wide range of applications in targeted audio delivery.Capacitive micromachined ultrasonic transducer(CMUTs)have great ... An air parametric array can generate a highly directional beam of audible sound in air,which has a wide range of applications in targeted audio delivery.Capacitive micromachined ultrasonic transducer(CMUTs)have great potential for air-coupled applications,mainly because of their low acoustic impedance.In this study,an air-coupled CMUT array is designed as an air parametric array.A hexagonal array is proposed to improve the directivity of the sound generated.A finite element model of the CMUT is established in COMSOL software to facilitate the choice of appropriate structural parameters of the CMUT cell.The CMUT array is then fabricated by a wafer bonding process with high consistency.The performances of the CMUT are tested to verify the accuracy of the finite element analysis.By optimizing the component parameters of the bias-T circuit used for driving the CMUT,DC and AC voltages can be effectively applied to the top and bottom electrodes of the CMUT to provide efficient ultrasound transmission.Finally,the prepared hexagonal array is successfully used to conduct preliminary experiments on its application as an air parametric array. 展开更多
关键词 Capacitive micromachined ultrasonic transducer Air–coupled Wafer bonding process Bias-T circuit optimization Parametric array
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A Novel Traveling Wave Ultrasonic Motor Using a Bar Shaped Transducer 被引量:4
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作者 金家楣 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第6期961-963,共3页
A novel traveling wave ultrasonic motor was proposed. The structure of the motor is rather simple and different from the conventional traveling wave ultrasonic motors. Its production processes are very convenient. It ... A novel traveling wave ultrasonic motor was proposed. The structure of the motor is rather simple and different from the conventional traveling wave ultrasonic motors. Its production processes are very convenient. It is composed of a stator constituted with a ring and a bar shaped transducer and two cone shaped rotors. The rotors were pressed on inner surface of the ring by means of a pre-pressure system. The bar shaped transducer has a sand- wich-like configuration,where two sets of piezoelectric element are bolted. One set excites a longitudinal vibration of the bar, and the other set excites a flexural vibration of the bar. The ring's traveling wave excited with the longitudinal vibration and the bending vibration of the bar transducer was simulated with FEM (finite element method). The prototype of the motor was made and investigated experimentally for its performance. Its maximum torque and rotating speed are 0.25 N · m and 50 r/min, respectively. 展开更多
关键词 ultrasonic motor traveling wave bar transducer
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Butein effects in colitis and interleukin-6/signal transducer and activator of transcription 3 expression 被引量:3
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作者 Sehe Dong Lee Jung Wan Choe +7 位作者 Beom Jae Lee Myoung Hee Kang Moon Kyung Joo Ji Hoon Kim Jong Eun Yeon Jong-Jae Park Jae Seon Kim Young-Tae Bak 《World Journal of Gastroenterology》 SCIE CAS 2015年第2期465-474,共10页
AIM: To evaluate the effects of butein on inflammatory cytokines, matrix metalloproteinase-9(MMP-9), andcolitis in interleukin(IL)-10-/- mice.METHODS: To synchronize colitis, 8- to 10-wk-old IL-10-/- mice were fed pel... AIM: To evaluate the effects of butein on inflammatory cytokines, matrix metalloproteinase-9(MMP-9), andcolitis in interleukin(IL)-10-/- mice.METHODS: To synchronize colitis, 8- to 10-wk-old IL-10-/- mice were fed pellet-chow containing piroxicam for 2 wk. Subsequently, phosphate-buffered saline or butein(1 mg/kg per day, ip) was injected for 4 wk. Histologic scores, inflammatory cytokines, MMP-9 and phosphorylated signal transducer and activator of transcription 3(p STAT3) expressions were analyzed in IL-10-/- mice and in Colo 205 cells.RESULTS: Butein reduced the colonic inflammatory score by > 50%. Expression levels of IL-6, IL-1β, interferon(IFN)-γ and MMP-9 were decreased in the colons of mice exposed to butein, whereas other inflammatory cytokines(IL-17 A, IL-21 and IL-22) were unchanged. Immunohistochemical staining for p STAT3 and MMP-9 was significantly decreased in the buteintreated groups compared with the controls. Butein inhibited IL-6-induced activation of STAT3 in Colo 205 cells.CONCLUSION: Butein ameliorated colitis in IL-10-/-mice by regulating IL-6/STAT3 and MMP-9 activation. 展开更多
关键词 BUTEIN Interleukin-6/signal transducer and activat
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Lamb wave signal selective enhancement by an improved design of meander-coil electromagnetic acoustic transducer 被引量:3
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作者 孙文秀 刘国强 +1 位作者 夏慧 夏正武 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期308-314,共7页
In this paper, we investigate a method of selectively enhancing the single mode signal of a Lamb wave by using a meander-coil electromagnetic acoustic transducer (EMAT) with a new magnetic configuration. We use the ... In this paper, we investigate a method of selectively enhancing the single mode signal of a Lamb wave by using a meander-coil electromagnetic acoustic transducer (EMAT) with a new magnetic configuration. We use the Lamb antisym- metric (A0) mode and symmetric (SO) mode as an example for analysis. The analytical expression of the magnitude of the spatial Fourier transform of the Lorentz force generated by different meander coils is used to determine the optimal driving frequency for single mode generation. The numerical calculation is used to characterize the new magnetic configuration and the conventional EMAT magnet. Experimental examinations of each meander coil in combination with the conventional and new magnetic configuration show that the Lamb wave signal can be selectively enhanced by choosing the appropriate driving frequency and coil parameters through using the improved meander-coil EMAT. 展开更多
关键词 Lamb wave selective enhancement meander-coil electromagnetic acoustic transducer (EMAT)
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Structure Optimization of Wheel Force Transducer Based on Natural Frequency and Comprehensive Sensitivity 被引量:2
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作者 Xiao-Long Zhang Ti Wu +1 位作者 Yan Shao Jian Song 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期973-981,共9页
The current research of wheel force transducer (WFT) mainly focuses on test signal processing and decoupling methods based on signal itself, while the WFT structure optimization research related to decreasing the ma... The current research of wheel force transducer (WFT) mainly focuses on test signal processing and decoupling methods based on signal itself, while the WFT structure optimization research related to decreasing the mass and increase the natural frequency and comprehen- sive sensitivity is not enough. In order to improve the WFT test accuracy, a structure optimization method based on natural frequency and comprehensive sensitivity indicators is put forward. The WPT with 8-beam elastic body is used for the finite element modeling (FEM), in which the fol- lowing variations are taken into consideration: the con- nection type of elastic body with modified rim, the number of connection holes, and the respects of strain beam including the shape, the cross sectional area and the length, etc.. The test results shows that the natural frequency of the connecting block type is increased by 65.5% compared with the connecting seat type of elastic body & modified rim, and the main channel sensitivity is improved as well. The results show that the connecting block type will achieve the best comprehensive performance when the number of connecting holes between the elastic body and the modified rim is 20. And the thinner and longer strain beam with smaller cross section area is preferable within the scope of elastic body mechanical strength. This research proposes a novel structure optimization method for WFT which contributes to improve the measurement performance of WFT. 展开更多
关键词 Wheel force transducer Structureoptimization Basic vibration frequency Comprehensivesensitivity Finite element method
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