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Force Compensation Control for Electro-Hydraulic Servo System with Pump-Valve Compound Drive via QFT-DTOC

Chinese Journal of Mechanical Engineering 2024年第2期37卷 228-246页

作者： Kaixian ba Yuan Wang Xiaolong He Chunyu Wang Bin Yu Yaliang Liu Xiangdong Kong Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Qinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China National Engineering Research Center for Local Joint of Advanced Manufacturing Technology and Equipment Yanshan UniversityQinhuangdao 066004China

Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ***,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy *** contrast,pump control systems offer a high ***,their response ability is *** fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of ***,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first *** addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC *** method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the ***,experimental verification is performed using the PCDS performance test *** experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the *** relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.

关键词： Legged robot Pump-valve compound drive system(PCDS) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO)

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Supertetragonal baZrS_(3):A promising perovskite sulphide with giant ferroelectricity and low band gap

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 126-133页

作者： Menglu Li sa Zhang Chenhan Liu Xiaotao Zu Liang Qiao Haiyan Xiao School of Physics University of Electronic Science and Technology of ChinaChengdu 611731China College of Mathematics and Physics Chengdu University of TechnologyChengdu 610059China Micro-and Nano-scale Thermal Measurement and Thermal Management Laboratory Ministry of Education Key Laboratory of Numerical Simulation of Large-Scale Complex SystemsSchool of Energy and Mechanical EngineeringNanjing Normal UniversityNanjing 210023China

Over the past century,ferroelectricity has offered exciting opportunities for fundamental research and device ***,most of the discovered excellent ferroelectrics are oxide materials with large band gaps,limiting their potential for optoelectronics *** using first-principles calculations we identify a new narrow-gap ferroelectric beyond oxides,i.e.,ferroelectric perovskite sulphide baZrS_(3).Under large compressive strains,baZrS_(3)can be stabilized into a unique supertetragonal phase with an extraordinary polarization of 67.16μC/cm^(2),which is even stronger than that of conventional oxide ***,the supertetragonal baZrS_(3)exhibits a direct narrow band gap of 1.2 eV and excellent electronic *** on the chemical bonding analysis,we attribute the formation of supertetragonal phase to charge re-ordering in which theπbond overlap along the long〈Zr-S〉bond completely vanishes and the antibonding states of theσbond appear below the Fermi *** work provides a conceptual strategy for designing new ferroelectrics for electronic and photovoltaic applications.

关键词： supertetragonal phase perovskite sulphide ferroelectricity

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Aggregation of CeAlO_(3) inclusions in heavy ingot of a steel containing 0.007% aluminum

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Journal of Iron and Steel Research International 2024年第8期31卷 1960-1972页

作者： Qiu-yue Zhou Jun-tao ba Lun Zhang Wei Chen Ying Ren Li-feng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The distribution of inclusions at the bottom of a Ce-treated heavy steel ingot was detected and *** three-dimensional morphology and spatial distribution of CeAlOs clusters were characterized using the electrolytic extraction and Micro-CT detection.A model of inclusion collision to predict the aggregation of CeAlO_(3) inclusions in the ingot was established and validated by measured *** were mainly CeAlO_(3) and a small amount of Ce_(2)O_(2)S in the tundish after cerium *** collision and aggregation of inclusions led to the formation of large clusters in the ingot during the solidification *** slag entrainment inclusions,large CeAO_(3) clusters and small CeAlO_(3) particles were observed from the center to the edge of the ingot *** inclusions were mainly concentrated at the *** number density of inclusions larger than 200μm was 0.21 mm^(-3).The maximum diameter of CeA1O_(3) clusters was 1340μ*** the edge to the radial center and from the bottom to the top,the average diameter of inclusions gradually increased due to the longer solidification time of the ingot.

关键词： Inclusion Heavy ingot Cerium treatment Collision

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Efficacy and safety of electroacupuncture for insomnia:A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第4期22卷 459-472页

作者： Han-yu Xu Lin-na Wu Yuan Zhang Te ba Xiao-feng Zhao Acupuncture and Moxibustion Department First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300193China National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300193China

background:Electroacupuncture is often used to treat ***:To evaluate the efficacy and safety of electroacupuncture for *** strategy:Databases including PubMed,Cochrane Library,Embase,Web of Science,Chinese Biomedical Literature Database,China National Knowledge Infrastructure,Wanfang Data and VIP Fulltext e-Journals Database were searched up to January 15,*** criteria:Randomized clinical trials were included if they compared the clinical efficacy and safety of electroacupuncture with sham acupuncture,no treatment or usual care (UC) and general *** extraction and analysis:The full texts of the studies were reviewed to remove ineligible *** extracted data included authors,publication year,diagnostic criteria,sample size,population characteristics,interventions and *** above steps were performed independently by two reviewers and the data were cross ***15.0 software was used to analyze the extracted outcome *** continuous data (Pittsburgh Sleep Quality Index[PSQI]score and Insomnia Severity Index score),weighted mean difference (WMD) was calculated and 95% confidence interval (CI) was reported when the same scale was *** dichotomous variables (clinical response rate and adverse events),a meta-analysis was performed using risk ratio (RR) as the effect ***:Thirty-one trials with 2226 subjects were *** meta-analysis suggested that electroacupuncture was more effective in improving insomnia compared with the control group (sham acupuncture,no treatment,UC and general acupuncture)(RR=1.21;95 CI:[1.16,1.27]),significantly reducing the PSQI score in insomnia patients after treatment and at follow-up (WMD=-3.23;95%CI:[-4.29,-2.17];P<0.001).There was no significant difference in the incidence of adverse events between the EA and control groups (sham acupuncture and no treatment or ***=1.48;95%CI:[0.91,2.40];P=0.117).In addition,the regression results revealed t

关键词： Electroacupuncture Insomnia Systematic review Meta-analysis

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Perianal disease in inflammatory bowel disease:Broadening treatment and surveillance strategies for anal cancer

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World Journal of Gastroenterology 2024年第28期30卷 3373-3385页

作者： Tatiana Pacheco sara Monteiro Luísa barros Jorge Silva Department of Gastroenterology Centro Hospitalar do Tamega e SousaPenafiel 4560-136Portugal

The perianal disease affects up to one-third of individuals with Crohn's disease(CD),causing disabling symptoms and significant impairment in quality of life,particularly for those with perianal fistulising CD(PFCD).The collaborative effort between gastroenterologists and surgeons is essential for addressing PFCD to achieve fistula closure and promote luminal *** fistula healing rates with conventional therapies have prompted the emergence of new biological agents,endoscopic procedures and surgical techniques that show promising *** these,mesenchymal stem cells injection is a particularly hopeful *** addition to the burden of fistulas,individuals with perianal CD may face an increased risk of developing anal *** underscores the importance of surveillance programmes and timely interventions to prevent late diagnoses and poor ***,there is no established formal anal screening *** this review,we provide an overview of the current state of the art in managing PFCD,including novel medical,endoscopic and surgical *** discussion also focuses on the relevance of establishing an anal cancer screening programme in CD,intending to propose a risk-based surveillance *** validation of this surveillance programme would be a significant step forward in improving patient care and outcomes.

关键词： Inflammatory bowel disease Crohn's disease Perianal Fistula Anus diseases Management Anal cancer Screening

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Spatiotemporal changes of gross primary productivity and its response to drought in the Mongolian Plateau under climate change

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Journal of Arid Land 2024年第1期16卷 46-70页

作者： ZHAO Xuqin LUO Min MENG Fanhao sa Chula baO Shanhu baO Yuhai College of Geographical Science Inner Mongolia Normal UniversityHohhot 010022China Inner Mongolia Key Laboratory of Remote Sensing and Geographic Information Systems Hohhot 010022China

Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by *** the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate *** this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during *** main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%***,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered *** aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central ***,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were *** warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to ***,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude *** cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 *** findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas.

关键词： gross primary productivity(GPP) climate change warming aridification areas drought sensitivity cumulative effect duration(CED) Mongolian Plateau

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Changes in microstructure and properties of weld heat-affected zone of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第8期31卷 2041-2052页

作者： Shu-jun Jia Qi-lin Ma Yu Hou ba Li He-song Zhang Qing-you Liu Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Collaborative Innovation Center for Steel Commonality University of Science and Technology BeijingBeijing 100083China Construction Project Management Branch of China National Petroleum Pipeline Network Group Co. Ltd.Langfang 065000HebeiChina

The evolution of the microstructure and toughness of APL5L X80 pipeline steel after thermal welding simulation was investigated by X-ray diffraction,electron backscatter diffraction,and transmission electron *** results indicated that primary heat-affected zones can be divided into weld,coarse-grained,fine-grained,intercritical,and sub-critical *** microstructure of the weld zone is mainly composed of bainitic ferrite and a small amount of granular bainite;however,the original austenite grains are distributed in the columnar *** structure of the coarse-grained zone is similar to that of the weld zone,but the original austenite grains are *** contrast,the microstructure in the fine-grained zone is dominated by fine granular bainite,and the effective grain size is only 8.15μm,thus providing the highest toughness in the entire heat-affected *** intercritical and subcritical zones were brittle valley regions,and the microstructure was dominated by granular ***,the martensite-austenite(M/A)constituents are present in island chains along the grain boundaries,and the coarse size of the M/A constituents seriously reduces the *** results of the crack propagation analyzes revealed that high-angle grain boundaries can significantly slow down crack growth and change the crack direction,thereby increasing the material *** impact toughness of the low-temperature tempering zone was equivalent to that of the columnar grain zone,and the impact toughness was between those of the critical and fine-grained zones.

关键词： Welding thermal simulation Impact toughness Crack propagation Martensite-austenite constituent High-strength low-alloy steel weld Heat-affected zone

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Bone marrow microRNA-34a is a good indicator for response to treatment in acute myeloid leukemia

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Oncology Research 2024年第3期32卷 577-584页

作者： MONA sa BDELLATEIF NAGLAA MHASsaN MAHMOUD MKAMEL YOMNA MEL-MELIGUI Department of Cancer Biology Medical Biochemistry and Molecular BiologyNational Cancer InstituteCairo UniversityCairo11976Egypt Department of Cinical Pathology National Cancer InstituteCairo UniversityCairo11976Egypt

background:microRNA 34a(miR 34a)had been reported to have a diagnostic role in acute myeloid leukemia(AML).However,its value in the bone marrow(BM)of AML patients,in addition to its role in response to therapy is still *** current study was designed to assess the diagnostic,prognostic,and predictive significance of miR 34a in the BM of AML ***:The miR.34a was assed in BM aspirate of 82 AML patients in relation to 12 normal control subjects using *** data were assessed for correlation with the relevant dinical critenia,response to therapy,disease-free survival(DFS),and overall survival(OS)***:miR.34a was significantly downregulated in AML patients[0.005(3.3×10^(-6)-1.32)],compared to the control subjects[0.108(3.2× 10^(-4)-1.64),p=0.021].*** relative quantification(RQ)of miR-34a was 0.106(range;0-32.12).The specifaity,sensitivity,and area under the curve(AUC)for the diagnosis of AML were(58.3%,69.5%,0.707,respectively,p=0.021).patients with upregulated miR-34a showed decreased platelets count<34.5 × 10^(9)/L,and achieved early complete remission(CR,p=0.031,p=0.044,respectively).Similarly,patients who were refractory to therapy showed decreased miR 34a levels in comparison to those who achieved CR[0.002(0-0.01)and 0.12(0-32.12),respectively,p=0.002].Therefore,miR 34a could significantly identify patients with CR with a specificity of 75%and sensitivity of 100%at a cut-off of 0.014(AUC=0.927,p=0.005).There was no considerable association between miR-34a expression and survival rates of the induded AML ***:miR-34a could be a beneficial diagnostic biomarker for AML *** addition,it serves as a good indicator for response to therapy,which could possibly identify patients who are refractory to treatment with 100%sensitivity and 75%specificity.

关键词： AML miR 34a microRNA Leukemia

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Gastric cancer secreted miR 214-3p inhibits the anti-angiogenesis effect of apatinib by suppressing ferroptosis in vascular endothelial cells

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Oncology Research 2024年第3期32卷 489-502页

作者： WEIXUE WANG TONGTONG WANG YAN ZHANG TING DENG HAIYANG ZHANG YI ba Department of GI Medical Oncology Tanjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin's Clinical Research Center for CancerTianjin Key Iaboratory of Digestive CancerKey Laboratory of Cancer Prevention and TherapyTianjin300060China

Diferent from necrosis,apoptosis,autophagy and other forms of cell death,ferroptosis is a mechanism that catalyzes lipid peroxidation of polyunsaturated ftty acids under the action of iron divalent or lipoxygenase,leading to cell *** is currently used in the third line standard treatment of advanced gastric cancer,targeting the anti-angiogenesis ***,Apatinib mediated ferroptosis in vascular endothelial cells has not been reported *** exosomes can be taken up into target cells to regulate tumor development,but the mechanism related to vascular endothelial cell ferroptosis has not yet been ***,we show that exosomes secreted by gastric cancer cells carry miR-214.3p into vascular endothelial cells and directdy target zinc finger protein A20 to negatively regulate ACSL4,a key enzyme of lipid peroxidation during frroptosis thereby inhibiting ferroptosis in vascular endothelial cells and reducing the eficiency of *** conclusion,inhibition of miR-214-3p can increase the sensitivity of vascular endothelial cells to Apatinib,thereby promoting the antiangiogenic efect of Apatinib,suggesting a potential combination therapy for advanced gastric cancer.

关键词： Cellular ferroptosis Exosome Tyrosine kinase inhibitor Gastrointestinal tumors miRNA

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Development and validation of a prognostic immunoinflammatory index for patients with gastric cancer

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World Journal of Gastroenterology 2024年第24期30卷 3059-3075页

作者： Zhi-Chang ba Xi-Qing Zhu Zhi-Guo Li Yuan-Zhou Li Department of Radiology Harbin Medical University Cancer HospitalHarbin 150081Heilongjiang ProvinceChina Department of Gastrointestinal Surgery Harbin Medical University Cancer HospitalHarbin 150081Heilongjiang ProvinceChina

baCKGROUND Studies have demonstrated the influence of immunity and inflammation on the development of *** single biomarkers of immunity and inflam-mation have been shown to be clinically predictive,the use of biomarkers integrating both to predict prognosis in patients with gastric cancer remains to be *** To investigate the prognostic and clinical significance of inflammatory biomarkers and lymphocytes in patients undergoing surgical treatment for gastric *** Univariate COX regression analysis was performed to identify potential prognostic factors for patients with gastric cancer undergoing surgical *** absolute shrinkage and selection operator-COX(LASSO-COX)regression analysis was performed to integrate these factors and formulate a new prognostic immunoinflammatory index(PII).The correlation between PII and clinical charac-teristics was statistically *** incorporating the PII score were devised and validated based on the time-dependent area under the curve and decision curve *** Patients exhibiting elevated neutrophil-to-lymphocyte ratio,platelet-to-lymphocyte ratio,and systemic immune inflammatory index displayed inferior progression-free survival(PFS)and overall survival(OS).Conversely,low levels of CD3(+),CD3(+)CD8(+),CD4(+)CD8(+),and CD3(+)CD16(+)CD56(+)T lymphocytes were associated with improved PFS and OS,while high CD19(+)T lymphocyte levels were linked to worse PFS and *** PII score demonstrated associations with tumor characteristics(primary tumor site and tumor size),establishing itself as an independent prognostic factor for both PFS and ***-dependent area under the curve and decision curve analysis affirmed the effectiveness of the PII-based nomogram as a robust prognostic predictive *** PII may be a reliable predictor of prognosis in patients with gastric cancer undergoing surgical treatment,and it offers insights into cancer-related immune-inflammatory re

关键词： Gastric cancer Immunity Inflammation Prognosis Nomogram

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