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Recent progress in functional modification and crosslinking of bioprosthetic heart valves

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Regenerative Biomaterials 2024年第1期3卷 1-16页

作者： Cheng Zheng li yang Yunbing Wang National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China

Valvular heart disease(VHD),clinically manifested as stenosis and regurgitation of native heart valve,is one of the most prevalent cardiovascular diseases with high *** valve replacement surgery has been recognized as golden standard for the treatment of *** to the clinical application of transcatheter heart valve replacement technic and the excellent hemodynamic performance of bioprosthetic heart valves(BHVs),implantation of BHVs has been increasing over recent years and gradually became the preferred choice for the treatment of ***,BHVs might fail within 10-15 years due to structural valvular degeneration(SVD),which was greatly associated with drawbacks of glutaraldehyde crosslinked BHVs,including cytotoxicity,calcification,component degradation,mechanical failure,thrombosis and immune *** prolong the service life of BHVs,much effort has been devoted to overcoming the drawbacks of BHVs and reducing the risk of *** this review,we summarized and analyzed the research and progress on:(i)modification strategies based on glutaraldehyde crosslinked BHVs and(ii)nonglutaraldehyde crosslinking strategies for BHVs.

关键词： bioprosthetic heart valves modification crosslinking anticalcification antithrombosis

Vision-based survey method for extraordinary loads on buildings

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Frontiers of Structural and Civil Engineering 2024年第6期18卷 815-831页

作者： yang li Jun CHEN Pengcheng WANG College of Civil Engineering Tongji UniversityShanghai 200092China China United Engineering Co.Ltd. Hangzhou 310052China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shanghai Key Laboratory of Engineering Structure Safety Shanghai Research Institute of Building Sciences Co.Ltd.Shanghai 200032China

The statistical modeling of extraordinary loads on buildings has been stagnant for decades due to the laborious and error-prone nature of existing survey methods,such as questionnaires and verbal *** study proposes a new vision-based survey method for collecting extraordinary load data by automatically analyzing surveillance *** this purpose,a crowd head tracking framework is developed that integrates crowd head detection and reidentification models based on convolutional neural networks to obtain head trajectories of the crowd in the survey *** crowd head trajectories are then analyzed to extract crowd quantity and velocities,which are the essential factors for extraordinary *** survey areas with frequent crowd movements during temporary events,the equivalent dynamic load factor can be further estimated using crowd velocity to consider dynamic effects.A crowd quantity investigation experiment and a crowd walking experiment are conducted to validate the proposed survey *** experimental results prove that the proposed survey method is effective and accurate in collecting load data and reasonable in considering dynamic effects during extraordinary *** proposed survey method is easy to deploy and has the potential to collect substantial and reliable extraordinary load data for determining design load on buildings.

关键词： load survey extraordinary load live load object detection multiple-object tracking

Optimizing air purification for household particulate matters using sensor-based and time-based intervention strategies

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Particuology 2023年第8期79卷 78-84页

作者： Meng Wang Tianjun Lu yang li Department of Epidemiology and Environmental Health School of Public and Health ProfessionsUniversity at BuffaloBuffalo14214USA Department of Earth Science and Geography California State UniversityDominguez HillsCarson90747USA Department of Environmental Science Baylor UniversityWaco76798USA

Filtration efficiency of portable air cleaner(PAC)is affected by resident perceptions and adherences to when and how to operate the *** PAC with smart control and sensor technology holds the promise to effectively reduce indoor air *** study aims to evaluate the efficiency of a PAC at removing indoor fine particulate matters(PM_(2.5))exposure under two automated operation settings:(1)a time-based mode in which the operation time is determined based on perceived time periods of indoor pollution by residents;(2)a sensor-based mode in which an air sensor monitor is used to determine the PAC based on the actual PM_(2.5) level against the indoor air quality *** study was conducted in a residential room for 55 days with a rolling setting on PAC(no filtration,sensor-based,time-based fil-trations)and a continuous measurement of PM_(2.5).We found that the PAC operated with sensor-based mode removed PM_(2.5) concentrations by 47%and prolonged clean air(<35 μg/m^(3))period by 23%compared to the purifications with time-based mode which reduced PM_(2.5) by 29%and increased clean air period by 13%.The sensor-based filtration identified indoor pollution episodes that are hardly detected by personal *** study findings support an automated sensor-based approach to optimize the use of PAC for effectively reducing indoor PM_(2.5) exposure.

关键词： Aircleaner Particulate matter Sensor-based filtration Time-based filtration Indoor pollution

Switching variability index based multiple strategy CFAR detector

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Journal of Systems Engineering and Electronics 2014年第4期25卷 580-587页

作者： yang li Zhenyuan Ji Bingfei li Gil Alterovitz Department of Electronic Engineering Harbin Institute of Technology Center for Biomedical Informatics Harvard University Chinese Aeronautical Radio Electronics Research Institute

A switching variability index （SVl） constant false alarm rate （CFAR） detector is proposed for improving the detection performance of VI-CFAR detectors in multiple targets backgrounds. When the presence of non-homogeneity in CFAR reference windows is indicated by a VI-CFAR detector, a switching- CFAR detector is introduced to optimize the performance of the VI-CFAR detector in homogeneous, multiple targets and clutter edge backgrounds. The structure and parameters selection method of the SVI-CFAR detector is presented. Comparisons with classic CFAR detectors and recently proposed detectors are also given. Theoretical analysis and simulation results show that SVICFAR detector maintains the good performance of the VI-CFAR detector in homogeneous and clutter edge backgrounds, while greatly improving the capacity of anti-multi targets.

关键词： switching variability index constant false alarm rate(SVI-CFAR) adaptive detection complex environment multiple-strategy detection radar target detection.

Recent advancements on the development of microgrids

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Journal of Modern Power Systems and Clean Energy 2014年第3期2卷 206-211页

作者： Qing li Zhao XU li yang Department of Electrical Engineering The Hong Kong Polytechnic UniversityHung HomHong KongChina School of Electrical Engineering Zhejiang UniversityYugu RoadHangzhouChina

With high penetration of distributed energy resources(DERs)into power systems,microgrid has showed great advantages of enabling efficient and reliable operation of distribution grids with high flexibilities and *** paper discusses the recent advancements of microgrid development with particular focus on different dispatch,and control schemes using distributed communication technologies,load management technology,and protection strategies applied in a microgrid *** also describes typical R&D activities and projects worldwide in *** Union(EU),Japan and the United States(US).Based on comprehensive review,it is convinced to conclude that microgrids could provide electricity supply with higher efficiency,reliability and quality to regional customers and will make contributions to smart grids development at large.

关键词： Microgrids Microgrid structure Multi-agent UFLS Controllable load Protection

On a class of quantum Turing machine halting deterministically

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Science China(Physics,Mechanics & Astronomy) 2013年第5期56卷 941-946页

作者： liANG Min yang li State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences

We consider a subclass of quantum Turing machines (QTM), named stationary rotational quantum Turing machine (SR-QTM), which halts deterministically and has deterministic tape head position. A quantum state transition diagram (QSTD) is proposed to describe SR-QTM. With QSTD, we construct a SR-QTM which is universal for all near-trivial transformations. This indicates there exists a QTM which is universal for the above subclass. Finally we show that SR-QTM is computational equivalent with ordinary QTM in the bounded error setting. It can be seen that SR-QTMs have deterministic tape head position and halt deterministically, and thus the halting scheme problem will not exist for this class of QTMs.

关键词： quantum Turing machine quantum circuit halting scheme quantum computational complexity

Roles of small RNAs in plant disease resistance

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Journal of Integrative Plant Biology 2014年第10期56卷 962-970页

作者： li yang Hai Huang Department of Biology University of North Carolina Chapel Hill National Laboratory of Plant Molecular Genetics Shanghai Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences The Chinese Academy of Sciences

The interaction between plants and pathogens represents a dynamic competition between a robust immune system and efficient infectious strategies. Plant innate immunity is composed of complex and highly regulated molecular networks, which can be triggered by the perception of either conserved or race-specific pathogenic molecular signatures. Small RNAs are emerging as versatile regulators of plant development, growth and response to biotic and abiotic stresses. They act in different tiers of plant immunity, including the pathogen-associated molecular pattern-triggered and the effector-triggered immunity. On the other hand, pathogens have evolved effector molecules to suppress or hijack the host small RNA pathways. This leads to an arms race between plants and pathogens at the level of small RNA-mediated defense. Here, we review recent advances in small RNA-mediated defense responses and discuss the challenging questions in this area.

关键词： Effector-triggered immunity microRNA pathogen-associated molecular pattern-triggered immunity small interfering RNA

Scalable solid-phase synthesis of defect-rich graphene for oxygen reduction electrocatalysis

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Green Energy & Environment 2023年第1期8卷 224-232页

作者： Chunxiao Dong li yang Cheng lian Xiaoling yang Yihua Zhu Hongliang Jiang Chunzhong li Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory for Ultrafine Materials of Ministry of Education School of Chemical EngineeringEast China University of Science and TechnologyShanghai200237China Institutes of Physical Science and Information Technology Anhui UniversityHefeiAnhui230601China School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai200237China

Defect-engineered carbon materials have been emerged as promising electrocatalysts for oxygen reduction reaction(ORR)in metal-air *** a facile strategy for the preparation of highly active nanocarbon electrocatalysts remains ***,a low-cost and simple route is developed to synthesize defective graphene by pyrolyzing the mixture of glucose and carbon *** dynamics simulations reveal that the graphene formation is ascribed to two-dimensional layered feature of carbon nitride,and high compatibility of carbon nitride/glucose *** measurements suggest that the graphene possesses rich edge and topological *** graphene catalyst exhibits higher power density than commercial Pt/C catalyst in a primary Zn-air *** experimental results and theoretical thermodynamic analysis,it is identified that graphitic nitrogen-modified topological defects at carbon framework edges are responsible for the decent ORR *** strategy presented in this work can be can be scaled up readily to fabricate defective carbon materials.

关键词： Carbon materials Electrocatalysis Oxygen reduction reaction Solid-phase synthesis Zn-air battery

Extraction of distributed parameters for multi-conductor transmission lines by the difference iteration method

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The Journal of China Universities of Posts and Telecommunications 2018年第5期25卷 93-100页

作者： yang li Lu Guizhen School of Information Engineering Communication University of China

The distributed parameters of the transmission lines have the significant impact to the signal propagation. In the conventional method of the distributed parameter extraction,the discontinuity of inverse trigonometric or hyperbolic can arise the problem about phase ambiguity which causes significant errors for transmission models. A difference iteration method（ DIM） is proposed for extracting distributed parameters of high frequency transmission line structure in order to overcome the phase ambiguity in the conventional method（ CM）. The formulations of the proposed method are first derived for two-conductor and multi-conductor lines. Then the validation is performed for the models of micro-strip transmission line. Numerical results demonstrate that the proposed DIM can solve the problem about the phase ambiguity and the extracted distributed parameters are accurate and efficient for a wide range of the frequencies of interest and line lengths.

关键词： two-conductor transmission line multi-conductor transmission line conventional method difference iteration method distributed parameters