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Cerebral perfusion in patients with unilateral internal carotid artery occlusion by dual post-labeling delays arterial spin labeling imaging

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World Journal of Radiology 2024年第9期16卷 429-438页

作者： Gui-Rong Zhang Yan-Yan Zhang wen-bin liang Dun Ding Department of Medical Imaging The Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710043Shaanxi ProvinceChina

BACKGROUND Global and regional cerebral blood flow(CBF)changes in patients with unilateral internal carotid artery occlusion(ICAO)are unclear when the dual post-labeling delays(PLD)arterial spin labeling(ASL)magnetic resonance imaging(MRI)technique is *** delineation of regions of interest for CBF measurement is time-consuming and *** To assess global and regional CBF changes in patients with unilateral ICAO with the ASL-MRI perfusion *** Twenty hospitalized patients with ICAO and sex-and age-matched controls were included in the *** CBF was measured by ***'s ASL *** present study evaluated differences in global,middle cerebral artery(MCA)territory,anterior cerebral artery territory,and Alberta Stroke Program Early Computed Tomography Score(ASPECTS)regions(including the caudate nucleus,lentiform nucleus,insula ribbon,internal capsule,and M1-M6)and brain lobes(including frontal,parietal,temporal,and insular lobes)between ICAO patients and controls at PLD 1.5 s and PLD 2.5 *** When comparing CBF between ICAO patients and controls,the global CBF in ICAO patients was lower at both PLD 1.5 s and PLD 2.5 s;the CBF on the occluded side was lower in 15 brain regions at PLD 1.5 s,and it was lower in 9 brain regions at PLD 2.5 s;the CBF in the contralateral hemisphere was lower in the caudate nucleus and internal capsule at PLD 1.5 s and in M6 at PLD 2.5 *** global CBF in ICAO patients was lower at PLD 1.5 s than at PLD 2.5 *** ipsilateral CBF at PLD 1.5 s was lower than that at PLD 2.5 s in 15 regions,whereas the contralateral CBF was lower at PLD 1.5 s than at PLD 2.5 s in 12 *** ipsilateral CBF was lower than the contralateral CBF in 15 regions at PLD 1.5 s,and in M6 at PLD 2.5 *** Unilateral ICAO results in hypoperfusion in the global and MCA territories,especially in the ASPECTS *** PLD settings prove more suitable for accurate CBF quantification in ICAO.

关键词： Arterial spin labeling Internal carotid artery occlusion Ischemic stroke Cerebral blood flow Hemodynamic

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Exoskeleton active assistance strategy for human muscle activation reduction during linear and circular walking

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Advances in Manufacturing 2024年第3期12卷 484-496页

作者： wen-Tao Sheng Ke-Yao liang Hai-bin Tang School of Intelligent Manufacturing Nanjing University of Science and TechnologyNanjing210094People’s Republic of China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin150001People’s Republic of China

The exoskeleton is employed to assist humans in various domains including military missions,rehabilitation,industrial operation,and activities of daily living(ADLs).Walking is a fundamental ADL,and exoskeletons are capable of reducing the activation and metabolism of lower extremity muscles through active assistance during *** improve the performance of active assistance strategy,this article proposes a framework using an active hip ***,it correlates to an already established Bayesian-based human gait recognition algorithm,with a particular focus on linear and circular walking within industrial and ADL *** theorizing this strategy for exoskeletons,this study further reveals,in part,the activation characteristics of human hip muscles for the instruction and regulation of active assistance duration and onset *** proposed active assistance strategy provides new insights for enhancing the performance of assistive robots and facilitating human robot interaction within the context of ADLs.

关键词： Human-robot interaction Hip exoskeleton Muscle activation Walking assistance

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Crosslinking Kinetics of Polyethylene with Small Amount of Peroxide and Its Influence on the Subsequent Crystallization Behaviors

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Chinese Journal of Polymer Science 2016年第9期34卷 1117-1128页

作者：牛艳华 wen-bin liang Yin-ling Zhang Xue-lian Chen Shih-yaw Lai Guang-xian Li Du-jin Wang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu 610065China Performance Material Center National Institute of Clean-and-low-carbon Energy(NICE)Beijing 102209China CAS Key Laboratory of Engineering Plastics Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Crosslinking reactions of high density polyethylene with low peroxide concentrations ranging from 0.1 wt% to 1.0 wt% at temperatures of 170, 180 and 190 ℃ were monitored by rheological measurements. A critical gel forms at the peroxide concentration of 0.2 wt%, where the transition from long chain branching generation to crosslinking network formation could occur. Rheokinetics of crosslinking can be fitted well by Ding-Leonov＇s model. The curing rate k2 at the earlier stage exhibits about 3 times acceleration per 10 ~C with increasing temperature, while the equilibrium modulus G＇ at the fully cured stage is almost independent of temperature. Influences of crosslinking on the subsequent crystallization behaviors were detected by DSC measurements. Above the critical gel concentration, crystallization is largely retarded as evidenced by the lower crystallization temperature Tc and crystallinity Xc due to the network formation. The secondary crystallization valley located at the temperature near 80 ℃ can be observed above the critical concentration, which becomes more evident with the increasing peroxide concentration and curing temperature. This phenomenon provides another evidence of crystallization retardation by the crosslinking network.

关键词： Polyethylene Rheology Crosslinking kinetics Crystallization.

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Macrophage-NLRP3 Inflammasome Activation Exacerbates Cardiac Dysfunction after Ischemic Stroke in a Mouse Model of Diabetes

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Neuroscience Bulletin 2020年第9期36卷 1035-1045页

作者： Hong-bin Lin Guan-Shan Wei Feng-Xian Li wen-Jing Guo Pu Hong Ya-Qian weng Qian-Qian Zhang Shi-Yuan Xu wen-bin liang Zhi-Jian You Hong-Fei Zhang Department of Anesthesiology Zhujiang Hospital of Southern Medical UniversityGuangzhou 510220China Department of Anesthesiology Shenzhen SAMII Medical CenterShenzhen 518118China Department of Anesthesiology The Second Affiliated HospitalShantou University Medical CollegeShantou 515041China University of Ottawa Heart Institute and Department of Cellular and Molecular Medicine University of OttawaOntarioK1NCanada

Ischemic stroke is one of the leading causes of death *** the post-stroke stage,cardiac dysfunction is common and is known as the brain-heart *** mellitus worsens the post-stroke ***-induced systemic inflammation is the major causative factor for the sequential complications,but the mechanism underlying the brain-heart interaction in diabetes has not been *** NLRP3(NLR pyrin domain-containing 3) inflammasome,an important component of the inflammation after stroke,is mainly activated in M1-polarized *** this study,we found that the cardiac dysfunction induced by ischemic stroke is more severe in a mouse model of type 2 ***,M1-polarized macrophage infiltration and NLRP3 inflammasome activation increased in the cardiac ventricle after diabetic ***,the NLRP3 inflammasome inhibitor CY-09 restored cardiac function,indicating that the Ml-polarized macrophage-NLRP3 inflammasome activation is a pathway underlying the brain-heart interaction after diabetic stroke.

关键词： Ischemic stroke Diabetes mellitus Cardiac dysfunction NLRP3 inflammasome Macrophage

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Evaluation of frictional pressure drop correlations for air-water and air-oil two-phase flow in pipeline-riser system

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Petroleum Science 2024年第2期21卷 1305-1319页

作者： Nai-liang Li bin Chen School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049ShaanxiChina

Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop.

关键词： Frictional pressure drop Pipeline-riser Gas-liquid two-phase flow Severe slugging Correlation

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The higher-order topological pumping explored in the 2D acoustic crystal

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 127-133页

作者： Yanqiu Wang bin liang Jianchun Cheng Key Laboratory of Modern Acoustics Ministry of EducationInstitute of AcousticsDepartment of PhysicsNanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

The topological pumping has been instrumental in advancing our understanding of topological phase transitions in various physical systems,which can be extended to uncover intriguing higher-order topological phases in the lower-dimensional ***,we propose a theoretical exploration of topological dipole pumping on an acoustic square superlattice by cyclically modulating intracell couplings,which shares the topological nature of an extended three-dimensional system with chiral hinge *** the multipole chiral numbers,we characterize the higher-order topological phases that arise during the *** evolution of topological phase transitions is verified by numerical simulations and shows corner states are transferred across the *** findings can inspire the construction of chiral hinge states in artificial crystals,opening up new possibilities for the design of devices allowing the unidirectional propagation of sound.

关键词： topological phases of matter Thouless pumping acoustic metamaterial

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Experimental study on failure mechanism of soft rock-coal bodies in abandoned mines under cyclic dynamic loading

Rock Mechanics Bulletin

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Rock Mechanics Bulletin 2024年第4期3卷 41-57页

作者： Dong Wang Yujing Jiang bin liang Zhijie wen Jianlong Wang State Key Laboratory of Mining Disaster Prevention and Control Co–Founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao266590China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing100083China Guizhou University Guiyang550525China

During the construction and operation of a pumped storage power station in an abandoned mine,the soft rockcoal body structure,comprising the roof and the residual coal pillars,encounters a complex stress environment characterized by cyclic *** study of its failure mechanism under cyclic dynamic loading holds significant theoretical and practical importance to stay the safety and stability of the abandoned mine pumped storage power *** this paper,we take“roof-residual coal pillar”soft rock-coal combinations with different percentages of rock as the research object,and study their mechanical properties,failure mechanism,energy evolution characteristics and acoustic emission distribution characteristics through cyclic dynamic loading *** results of the experiment indicate that:(1)Both weak cyclic dynamic loading and high rock percentage enhance the deformation resistance of soft rock-coal *** low-disturbance horizontal cyclic loading,its peak strength and modulus of elasticity increase with increasing rock percentage.(2)Under low-disturbance horizontal cyclic loading,an increasing trend is observed in the average total strain energy density,dissipation energy density,and elastic energy density of the combinations as the percentage of rock increases.(3)Under lowdisturbance horizontal cyclic loading,as the percentage of rock increases in the soft rock-coal combinations,the degree of failure in the rock body part progressively intensifies,while the destruction of the coal portion progressively decreases.(4)The large number of acoustic emission signals are generated at the instant of destabilization and destruction of the coal-rock combinations,mainly dominated by the signals generated by the destruction of the coal *** emission counts and absolute energy at key point N2 decrease as the percentage of rock *** b value is primarily distributed in the cyclic dynamic loading stage and the failure stage,both displaying

关键词： Soft rock-coal combinations Energy evolution Failure mechanism Cyclic dynamic loading Acoustic emission

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Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 43-50页

作者： Xiao-bin liang Bo Li Shao-Ming Fei School of Mathematics and Computer Science Shangrao Normal UniversityShangrao 334001China Quantum Information Research Center Shangrao Normal UniversityShangrao 334001China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical ***,we introduce the concept of optimal observable sets and define the tightest uncertainty constants to accurately describe these measurement *** any quantum state,we establish optimal sets of three observables for both product and summation forms of uncertainty relations,and analytically derive the corresponding tightest uncertainty *** demonstrate that the optimality of these sets remains consistent regardless of the uncertainty relation ***,the existence of the tightest constants excludes the validity of standard real quantum mechanics,underscoring the essential role of complex numbers in this ***,our findings resolve the conjecture posed in[***.118,180402(2017)],offering novel insights and potential applications in understanding preparation uncertainties.

关键词： uncertainty relation the tightest uncertainty constants optimal observable sets

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Distributed user pairing and effective computation offloading in aerial edge networks

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Chinese Journal of Aeronautics 2024年第4期37卷 378-390页

作者： Wei liang Shuhui wen Lixin LI Jingjing CUI School of Electronics and Information Northwestern Polytechnical UniversityXi’an CN710072China The State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an CN710126China School of Electronics and Computer Science University of SouthamptonSouthampton SO167NSUK

Future Sixth-Generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous ***,the aerial networks are the key framework for the future communications,in which the aerial vehicle could act as the access ***,Mobile Edge Computing (MEC) is also essential to enhance the data processing capabilities of aerial *** this paper,we study a comprehensive communication-computation resource management problem for jointly optimizing user pairing,power and time allocation in the MEC aided Cognitive Radio (CR) aerial networks,namely CR-MEC aerial ***,this multilevel optimization problem could be decomposed into the user pairing and power allocation as well as time allocation *** the conceived CR-MEC aerial networks,we propose a User Pairing and Computation Offloading Management Algorithm (UPCOMA) based on three-sided matching theory,aiming to minimize the system’s energy *** the first step of UPCOMA,multiple Primary Users (PUs) and Cognitive Users (CUs) on the ground negotiate to each other with the suitable power allocation coefficients and construct the stable user ***,the stable user pairs would match to a high altitude platform who act as the base station,which is for appropriately allocating Transmission Time Slots (TSs) at the second step of ***,a hybrid offloading mode is proposed in our conceived networks in order to support ground users to offload their tasks adaptively according to their individual ***,the simulation results reveal that the relative performance of UPCOMA is close to that of the Brute-Force Search Algorithm (BFSA) with low ***,the hybrid offloading mode with less energy consumption supports much more ground user pairs to offload tasks compared to the binary mode.

关键词： Aerial edge computing binary offloading Cognitive radio Hybrid offloading Resource management

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All types of base conversions allowed by base editors

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Science China(Life Sciences) 2024年第2期67卷 431-433页

作者： Shun-Qing liang wen Xue RNA Therapeutics Institute UMass Chan Medical SchoolWorcester 01655USA Department of Molecular Cell and Cancer BiologyUMass Chan Medical SchoolWorcester 01655USA Department of Molecular Medicine UMass Chan Medical SchoolWorcester 01655USA Li Weibo Institute for Rare Diseases Research UMass Chan Medical SchoolWorcester 01655USA

Base editors(BEs) hold great promise as tools for introducing single-base-pair changes in both basic research and therapeutic applications(Rees and Liu,2018).Base editors are composed of a Cas9 nickase fused to a DNA-modifying enzyme,which chemically modifies nucleobases within a specific targeting window near the Cas9-binding site.

关键词： base bases allowed

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