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Beta-blocker use and risk of symptomatic bradyarrhythmias： a hospital-based case-control study

Journal of Geriatric Cardiology 2016年第9期13卷 749-759页

作者： hou tee lu Jiyen Kam Rusli Bin Nordin Surinder Kaur Khelae Jing Mein Wang Chun Ngok Choy Chuey Yan Lee Clinical School Johor Bahru Jeffrey Cheah School of Medicine and Health Sciences Monash University Malaysia Johor Bahru Johor Malaysia Department of Cardiology Sultanah Aminah Hospital Jalan Masjid Abu Bakar Johor Bahru Johor Malaysia Department of Electrophysiology lnstitut Jantung Negara Jalan Tun Razak Kuala Lumpur Malaysia Department of Pharmacy Sultanah Aminah Hospital Jalan Masjid Abu Bakar Johor Bahru Johor Malaysia

Objective To investigate the risk factors of symptomatic bradyarrhythrnias in relation to β-blockers use. Methods A hospital-based case-control study [228 patients： 108 with symptomatic bradyarrhythmias （cases） and 120 controls] was conducted in Sultanah Aminah Hospital, Malaysia between January 2011 and January 2014. Results The mean age was 61.1 ~ 13.3 years with a majority of men （68.9%）. Cases were likely than control to be older, hypertensive, lower body mass index and concomitant use of rate-controlling drugs （such as digoxin, verapamil, diltiazem, ivabradine or amiodarone）. Significantly higher level of serum potassium, urea, creatinine and lower level of estimated glomerular filtration rate （eGFR） were observed among cases as compared to controls. On univariate analysis among patients on β-blockers, older age （crude OR： 1.07; 95% CI： 1.03-1.11, P = 0.000）, hypertension （crude OR： 5.6; 95% CI： 1.51-20.72, P = 0.010）, lower sodium （crude OR： 0.04; 95% CI： 0.81-0.99, P = 0.036）, higher potassium （crude OR： 2.36; 95% CI： 1.31-4.26, P = 0.004） and higher urea （crude OR： 1.23; 95% CI： 1.11-1.38, P = 0.000） were associated with increased risk of symptomatic bradyarrhythmias; eGFR was inversely and significantly associated with symptomatic bradyarrhythmias in both ＇β-blockers＇（crude OR： 0.97; 95% CI： 0.964）.98, P = 0.000） and ＇non-β-blockers＇（crude OR： 0.99; 95% CI： 0.97-0.99, P = 0.023） arms. However, eGFR was not significantly associated with symptomatic bradyarrhythmias in the final model of both ＇β-blockers＇（adjusted OR： 0.98; 95% CI： 0.96-0.98, P = 0.103） and ＇non-p-blockers＇（adjusted OR： 0.99; 95% CI： 0.97-1.01, P = 0.328） arms. Importantly, older age was a significant predictor of symptomatic bradyarrhythmias in the ＇β-blockers＇ as compared to the ＇non-β-blockers＇ arms （adjusted OR： 1.09; 95% CI： 1.03-1.15, P = 0.003 vs. adjusted OR： 1.03; 95% CI： 0.98-1.09, P = 0.232, respectively）. Conclusion Older age was a significant predictor of symptomatic bradyarr

关键词： Adverse drug reaction Beta-blocker Bradyarrhythmias Case-control

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Grain-boundary segregation and grain growth in nanocrystalline substitutional solid solution alloys

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Journal of Materials Science & Technology 2024年第1期168卷 239-249页

作者： Fawei Tang Chao hou Hao lu Zhi Zhao Xiaoyan Song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gibbs free energy of segregation was introduced to evaluate the segregating capability of the solute elements in a closed system,through which the influences of grain boundary structure,grain size,ma-terial composition,and external conditions were *** on the evaluation of various energy forms related to solute segregation and grain growth processes,the nature of the thermal stabilization of nanograin structures by solute segregation was disclosed.A criterion for the destabilization of nanostruc-tures,which is determined by the competition of the change rates between the molar Gibbs free energy of segregation and the total energy of grain boundaries with grain size,has been *** study provided guideline to achieve high-temperature stability of nanograin structures of solid solution alloys even for the weakly segregating nanocrystalline systems.

关键词： Substitutional solid solution Grain boundary segregation Thermal stabilization Solute concentration Grain size

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Wind disturbance compensated path-following control for fixed-wing UAVs in arbitrarily strong winds

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Chinese Journal of Aeronautics 2024年第2期37卷 431-445页

作者： Hao lu Lan GAO Yunda YAN Mingzhe hou Chenliang WANG Hangzhou Innovation Institute Beihang UniversityHangzhou 310051China School of Information Science and Technology Hangzhou Normal UniversityHangzhou 311121China Department of Computer Science University College LondonLondon WC1E 6BTUnited Kingdom Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Wind is the primary challenge for low-speed fixed-wing unmanned aerial vehicles to follow a predefined flight *** cope with various wind conditions,this paper proposes a wind disturbance compensated path following control strategy where the wind disturbance estimate is incorporated with the nominal guiding vector field to provide the desired airspeed direction for the *** the control input vector for the outer-loop kinematic subsystem needs to satisfy a magnitude constraint,a scaling mechanism is introduced to tune the proportions of the compensation and nominal ***,an optimization problem is formulated to pursue a maximum wind compensation in strong winds,which can be solved analytically to yield two scaling factors.A cascaded inner-loop tracking controller is also designed to fulfill the outer-loop wind disturbance compensated guiding vector ***-fidelity simulation results under sensor noises and realistic winds demonstrate that the proposed path following algorithm is less sensitive to sensor noises,achieves promising accuracy in normal winds,and mitigates the deviation from a desired path in wild winds.

关键词： Path following Guiding vector field Wind disturbance Disturbance rejection Fixed wings

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The corrosion characteristic and mechanism of Mg-5Y-1.5Nd-xZn-0.5Zr(x=0,2,4,6 wt.%)alloys in marine atmospheric environment

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Journal of Magnesium and Alloys 2024年第1期12卷 139-158页

作者： Quantong Jiang Dongzhu lu Liren Cheng Nazhen Liu Baorong hou CAS Key Laboratory of Marine Environmental Corrosion and Bio-fouling Institute of OceanologyChinese Academy of SciencesNo.7 Nanhai RoadQingdao 266071PR China State Key laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesNo.5625 Renmin StreetChangchun 130022PR China Open Studio for Marine Corrosion and Protection Pilot National Laboratory for Marine Science and Technology(Qingdao)No.1 Wenhai RoadQingdao 266071PR China Sanya Institute of Oceanology South China Sea Institute of OceanologyChinese Academy of SciencesZhenzhou RoadSanya 572000PR China

The microstructure and precipitated phases of as-cast Mg-5Y-1.5Nd-x Zn-0.5Zr(x=0,2,4,6 wt.%)alloys were investigated by optical microscopy,scanning electron microscopy,energy-dispersive spectrometry and X-ray *** exposure corrosion experiment of these magnesium alloys was tested in South China Sea and KEXUE vessel atmospheric *** corrosion characteristic and mechanism of magnesium alloys of Mg-5Y-1.5Nd-x Zn-0.5Zr(x=0,2,4,6 wt.%)alloys were analyzed by weight loss rate,corrosion depth,corrosion products and corrosion *** electrochemical corrosion tests were also measured in the natural *** comprehensive results showed that Mg-5Y-1.5Nd-4Zn-0.5Zr magnesium alloy existed the best corrosion resistance whether in the marine atmospheric environment and natural seawater *** depended on the microstructure,type and distribution of precipitated phases in Mg-5Y-1.5Nd-4Zn-0.5Zr magnesium *** quantity anodic precipitated phases in the microstructure of Mg-5Y-1.5Nd-4Zn-0.5Zr alloy played the key role in the corrosion resistance.

关键词： Marine atmospheric environment Exposure corrosion Magnesium alloy Corrosion rate Corrosion mechanism

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Spatiotemporal variation of rainy season span and precipitation recorded by lacustrine laminated pollen in the Tibetan Plateau during the past two millennia

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Science China Earth Sciences 2024年第3期67卷 789-801页

作者： Anning CUI houyuan lu Juzhi hou Xingqi LIU Deke XU Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Group of Alpine Paleoecology and Human Adaptation State Key Laboratory of Tibetan Plateau Earth SystemResources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Capital Normal University College of Resource Environment and Tourism Beijing 100048China

The quantitative reconstruction of the length of the rainy season and precipitation on the Tibetan Plateau(TP) is crucial for revealing the spatiotemporal evolution of the Westerlies and Asian summer monsoon, as well as its ecological and environmental effects. Accurately determining the start and end times of the rainy season on the Plateau remains *** study determined the start and end times of the rainy season in different locations on the Plateau by identifying precipitation inflection points. We calculated the duration and precipitation amount of the rainy season and established a transfer function between the modern pollen assemblages and them. Then, we reconstructed the rainy season variations in Kusai Lake(northern TP) and Jiang Co(central TP) during the past two millennia. The results showed that, the rainy season precipitation in Kusai Lake recorded five periods of high precipitation: AD 580–680, 1000–1100, 1200–1450, 1550–1780, and 1920–present, corresponding to the stages with long rainy season. The rainy season precipitation sequence in Jiang Co recorded four periods of high precipitation: AD 80–500, 800–950, 1250–1450, and 1780–present, which is consistent with the long rainy season before AD 1000 but unclear afterward. Spatially, rainy season precipitation on the Plateau exhibited four patterns: “wet in both north and south” may be related to abnormally strong summer monsoons;“dry in both north and south” likely associated with weak Westerly wind and weak summer monsoon;“wet in the south and dry in the north” linked to strong summer monsoon and weak Westerly wind;and “dry in the south and wet in the north” connected to weak summer monsoon and strong Westerly wind. This study revealed the spatiotemporal evolution pattern of the rainy season onset and end, duration, and precipitation amount on the Plateau over the past two millennia. It provides natural background support for further understanding the coupling between Westerly wind and Asia

关键词： Tibetan Plateau Past two millennia Rainy season length Rainy season precipitation Quantitative reconstruction

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Effect of Post-weld Heat Treatment on the Microstructure and Mechanical Properties of 2.25Cr-1Mo-0.25V Ultra-Thick Steel Plate

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 1104-1114页

作者： Yanyang Wu Zongye Ding Wenquan lu Jingchao hou Qiaodan Hu Jianguo Li Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai200444China School of Mechatronic Engineering and Automation Foshan UniversityFoshan528225GuangdongChina WuYang Iron and Steel Wugang450000HenanChina

Ensuring the homogeneous and excellent mechanical properties of 2.25Cr-1Mo-0.25V ultra-thick steel plate is the key to the production of hydrogenation reactor ***,it is required to understand the heterogeneity of microstructures and properties of ultra-thick plate after heat *** this work,the effect of post-weld heat treatment(PWHT)on the strength,plasticity,toughness and microstructures of the 193-mm-thick steel plate was investigated,and the formation mechanism of heterogeneity was *** PWHT decreased the room-and high-temperature yield strength(YS)and ultimate tensile strength(UTS)of the steel plate after normalizing and tempering(NT),while the room-and high-temperature YS and UTS decreased from the surface to the center of 193-mm-thick steel *** was attributed to the enhanced decomposition of martensite-austenite(M-A)constituents and coarsening of grains and precipitated carbides.

关键词： Cr-Mo steel Ultra-thick steel plate Microstructure Mechanical properties Heterogeneity

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Controlling reversible complexation-mediated polymerization(RCMP)via deep eutectic solvents:fast kinetics,narrow molecular weight distribution and mechanistic insights

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Science China Chemistry 2024年第8期67卷 2728-2736页

作者： Xin Fu Zhen lu Shen Li Zheng-Hong luo Lin-Xi hou Department of Materials-Oriented Chemical Engineering College of Chemical EngineeringFuzhou UniversityFuzhou 350116China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200030China Chemical Engineering Zhicheng College of Fuzhou UniversityFuzhou 350116China Qingyuan Innovation Laboratory Quanzhou 362801China

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric *** this work,serials of deep eutectic solvents(DES)with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization(RCMP)for the first time,yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil *** mechanism and elementary reaction of RCMP were explored deeply,revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization ***,the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic *** investigation demonstrated the considerable potential of DES for RCMP,which is anticipated for other polymerization applications as a novel medium mode.

关键词： deep eutectic solvent reversible complexation-mediated polymerization intermolecular hydrogen bonding density functional theory elementary reaction steps

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Microstructure and damping properties of LPSO phase dominant Mg-Ni-Y and Mg-Zn-Ni-Y alloys

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Journal of Magnesium and Alloys 2024年第3期12卷 1131-1153页

作者： Ruopeng lu Kai Jiao Nanting Li Hua hou Jingfeng Wang Yuhong Zhao College of Materials Science and Engineering North University of ChinaTaiyuan 030051China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

This work studied the microstructure,mechanical properties and damping properties of Mg_(95.34)Ni_(2)Y_(2.66) and Mg_(95.34)Zn_(1)Ni_(1)Y_(2.66)alloys *** difference in the evolution of the long-period stacked ordered(LPSO)phase in the two alloys during heat treatment was the *** morphology of the as-cast Mg_(95.34)Ni_(2)Y_(2.66)presented a disordered *** heat treatment at 773 K for 2 hours,the eutectic phase was integrated into the matrix,and the LPSO phase maintained the 18R *** Zn partially replaced Ni,the crystal grains became rounded in the cast alloy,and lamellar LPSO phases and more solid solution atoms were contained in the matrix after heat treatment of the Mg_(95.34)Zn_(1)Ni_(1)Y_(2.66)*** Zn and the heat treatment had a significant effect on *** dislocation internal friction peaks and grain boundary internal friction peaks were found after temperature-dependent damping of the Mg_(95.34)Ni_(2)Y_(2.66)and Mg_(95.34)Zn_(1)Ni_(1)Y_(2.66)*** heat treatment,the dislocation peak was significantly increased,especially in the alloy Mg_(95.34)Ni_(2)Y_(2).*** annealed Mg_(95.34)Ni_(2)Y_(2.66)alloy with a rod-shaped LPSO phase exhibited a good damping performance of 0.14 atε=10^(−3),which was due to the difference between the second phase and solid solution atom *** factors also affected the dynamic modulus of the *** results of this study will help in further development of high-damping magnesium alloys.

关键词： Mg-Ni-Y alloys Mg-Zn-Ni-Y alloys LPSO phase Heat treatment Microstructure Damping properties.

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Mathematical model and numerical investigation of the influence of spray drying parameters on granule sizes of mold powder

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Particuology 2024年第2期85卷 280-295页

作者： Fei Zhang Youyu lu Shaoyan Zhu Funian Han Guanghua Wen Ping Tang Zibing hou College of Materials Science and Engineering Chongqing UniversityChongqing400044China Guizhou Academy of Testing and Analysis Guizhou Academy of SciencesGuiyang550014China

In this work,the formation mechanism of the droplet-to-granule was investigated in detail based on mold powder manufacturing.A specific mathematical model of two-stage spray drying was established to describe droplet and granule motion,heat and mass transfer,and granule morphology during spray ***,the relationships between spray drying parameters(inlet temperature,atomization pres-sure,slurry mass flow rate)and the properties of the drying tower(temperature and velocity fields)and mold powder granules(temperature,evaporation rates,moisture content,and diameter)were simulated and calculated using ANSYS/Fluent *** ensure that the granule size of mold powder was controlled within the ideal range(0.2-0.6 mm)for producing granules with appropriate mechanical and metallurgical properties,the following optimum spray drying parameters were chosen based on the results of the numerical simulation:inlet temperatures,873 K;slurry atomization pressure,1.8 MPa;slurry mass flow rate,0.05 kg *** these parameters,the slurry mass flow rate has the most significant effect on granule size.

关键词： Mold powder slurry Spray drying parameters Mathematical model Numerical simulation Granule sizes

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Regulating photothermal properties of near-infrared croconaine dyes by supramolecular assembly

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Nano Research 2024年第9期17卷 8560-8570页

作者： Yangge Ren Yue lu Juanjuan Gao Yi Ding Bo Zhu Xinyu hou Lin Jia Department of Polymer Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Department of Electronic Information Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The photochemical and photophysical properties of near-infrared(NIR)dyes are significantly influenced by their aggregation state and mesoscopic ***,beyond chemical synthesis,the regulation mechanisms for the properties of NIR dyes,particularly with respect to photothermal properties of the aggregates,are not yet fully ***,we investigate the photothermal behaviors of croconaine-based(CroA)NIR dyes containing dipeptide or amino acids *** introduction of hydrogen bonding promotesπ-πstacking of croconaine center,which can efficiently regulate aggregation states and assembly structures in *** laser irradiation,CroA aggregates undergo aggregation-dissociation transition,the in-situ monomer generation process regulates two parameters of photothermal performance:heating rates and plateau photothermal *** study reveals the regulation effect of non-covalent bonding interactions on CroA aggregates,highlighting supramolecular assembly strategy not only facilitates to construct of photothermal nanomaterials with well-defined structures,but also provides an alternative and effective method for regulating photothermal performance of NIR dyes.

关键词： croconaine dye hydrogen bonding photothermal performance supramolecular assembly chirality

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