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Crossover patterns under meiotic chromosome program

Asian Journal of Andrology 2021年第6期23卷 562-571页

作者： Shunxin Wang Yongliang Shang Yanlei Liu Binyuan Zhai Xiao Yang Liangran Zhang Center for Reproductive Medicine Cheeloo College of MedicineShandong UniversityJinan 250012China Key Laboratory of Reproductive Endocrinology of Ministry of Education Shandong UniversityJinan 250012China Shandong Key Laboratory of Reproductive Medicine Jinan 250012China Shandong Provincial Clinical Research Center for Reproductive Health Jinan 250012China National Research Center for Assisted Reproductive Technology and Reproductive Genetics Shandong UniversityJinan 250012China Advanced Medical Research Institute Shandong UniversityJinan 250014China State Key Laboratory of Microbial Technology Shandong UniversityQingdao 266237China

Repairing DNA double-strand breaks(DSBs)with homologous chromosomes as templates is the hallmark of meiosis.The critical outcome of meiotic homologous recombination is crossovers,which ensure faithful chromosome segregation and promote genetic diversity of progenies.Crossover patterns are tightly controlled and exhibit three characteristics:obligatory crossover,crossover interference,and crossover homeostasis.Aberrant crossover patterns are the leading cause of infertility,miscarriage,and congenital disease.Crossover recombination occurs in the context of meiotic chromosomes,and it is tightly integrated with and regulated by meiotic chromosome structure both locally and globally.Meiotic chromosomes are organized in a loop-axis architecture.Diverse evidence shows that chromosome axis length determines crossover frequency.Interestingly,short chromosomes show different crossover patterns compared to long chromosomes.A high frequency of human embryos are aneuploid,primarily derived from female meiosis errors.Dramatically increased aneuploidy in older women is the well-known“maternal age effect.”However,a high frequency of aneuploidy also occurs in young women,derived from crossover maturation inefficiency in human females.In addition,frequency of human aneuploidy also shows other age-dependent alterations.Here,current advances in the understanding of these issues are reviewed,regulation of crossover patterns by meiotic chromosomes are discussed,and issues that remain to be investigated are suggested.

关键词： aneuploidy chromosome crossover crossover interference crossover pattern meiosis recombination

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A Novel 6‑DOF Force‑Sensed Human‑Robot Interface for an Intuitive Teleoperation

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Chinese Journal of Mechanical Engineering 2022年第6期35卷 76-88页

作者： Zihao Li Fugui Xie yanlei Ye Peng Li Xinjun liu State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Lab of Precision/Ultra‑Precision Manufacturing Equipments and Control Tsinghua UniversityBeijing 100084China

The teleoperation of a 6 degrees-of-freedom(DOF)manipulator is one of the basic methods to extend people’s capabilities in the wide variety of applications.The master interface based on the force/torque(FT)sensor could provide the full-dimension intuitive teleoperation of a 6-DOF robot since it has the ability to trigger 6-DOF command input.However,due to the force coupling,noise disturbance and unlimited input signals of the FT sensor,this force-sensed interface could not be widely used in practice.In this paper,we present an intuitive teleoperation method based on the FT sensor to overcome these challenges.In this method,the input signals from the force-sensed joystick were filtered and then processed to the force commands by force limit algorithm,with the merits of anti-interference,output limitation,and online velocity adjustment.Furthermore,based on the admittance control and position controller,the manipulator could be teleoperated by the force commands.Three experiments were conducted on our self-designed robotic system.The result of the first experiment shows that the interfered force from the force coupling could be effectively suppressed with the limitation of the input force through force limit algorithm.Then,a parameter was introduced in the other two experiments to adjust the velocity online practically with force limit algorithm.The proposed method could give a practical solution to the intuitive teleoperation based on the FT sensor.

关键词： Force-sensed interface Haptic control Force coupling Teleoperation Human-robot interaction

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Adaptive learning path recommendation model for examination-oriented education

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The Journal of China Universities of Posts and Telecommunications 2022年第4期29卷 77-88页

作者： Wang Jian Qiao Kuoyuan Yuan yanlei liu Xiaole Yang Jian School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou 450001China Research and Development Department Tongfang Knowledge Network Technology Company LimitedBeijing 100192China The Teaching Affaires Office Zhengzhou Hi-Tech Zone Langyuehui Foreign Language Middle SchoolZhengzhou 450001China Yunnan Key Laboratory of Smart City in Cyberspace Security Yuxi Normal UniversityYuxi 653100China

Adaptive learning paths provide individual learning objectives that best match a learner’s characteristics.This is especially helpful when learners need to balance limited available learning time and multiple learning objectives.The automatic generation of personalized learning paths to improve learning efficiency has therefore attracted significant interest.However,most current research only focuses on providing learners with adaptive objects and sequences according to their own interests or learning goals given a normal amount of time or ordinary conditions.There is little research that can help learners to obtain the most important knowledge for a test in the shortest time possible,which is a typical scenario in exanimation-oriented education systems.This study aims to solve this problem by introducing a new approach that builds on existing methods.First,the eight properties in Gardner’s multiple intelligence theory are introduced into the present knowledge and learner models to define the relationship between learning objects(LOs)and learners,thereby improving recommendation accuracy rates.Then,a novel adaptive learning path recommendation model is presented where viable knowledge topologies,knowledge bases and the previously-established properties relating to a learner’s ability are combined by Dempster-Shafer(D-S)evidence theory.A series of practical experiments were performed to assess the approach’s adaptability,the appropriateness of the selected evidence and the effectiveness of the recommendations.In the results,it was found that the proposed learning path recommendation model helped learners learn the most important elements and obtain superior test grades when confronted with limited time for learning.

关键词： adaptive learning learning path recommendation Dempster-Shaferevidence theory knowledge model learner model

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Smart ionic liquid/water mixture system with dual stimuli-response to temperature and CO_(2)

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Nano Research 2023年第3期16卷 4152-4159页

作者： Xiaoqing Yuan Ju liu Jingyu Qin Weili Ma Guangyong liu yanlei Wang Hongyan He Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex SystemsCAS Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China

Stimuli-responsive materials have important applications in chemistry and chemical engineering.Here,we synthesized five different polyetheramine-fatty acids(PEFA)ionic liquids(ILs),possessing the dual stimuli-responsive ability to temperature and CO_(2).These PEFA ILs have reversible lower critical solution temperature(LCST)phase behavior over a wide temperature range of 37-91℃,and reversible heterogeneous-homogeneous phase transition towards the addition and removal of CO_(2).Furthermore,the droplet size of the IL-water mixture system increased from 6.5 to 21.0 nm as the temperature increased from 25 to 56℃,and then recovered to 6.5 nm when the temperature decreased to 25℃.The addition and removal of CO_(2)also reversibly modulated the droplet size of the system.Results from nuclear magnetic resonance(NMR)and Fourier transform infrared(FTIR)spectra further showed that the temperature-dependent conformation of polyether amine chain in the cation dominates the temperature response,while the reversible formation of bicarbonate and fatty acids(FA)from CO_(2)and anion controls the CO_(2)-based reversible phase transition.Molecular simulations revealed a microscopic response mechanism of the IL-water system to temperature and CO_(2),and a synergistic effect between the dual stimuli of temperature and CO_(2).These findings may provide a basis for the rational design and understanding of ILs-based stimuli-responsive materials and nanoreactors.

关键词： stimuli-responsive ionic liquids phase transitions temperature CO_(2)

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High-impedance Fault Detection Method Based on Feature Extraction and Synchronous Data Divergence Discrimination in Distribution Networks

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Journal of Modern Power Systems and Clean Energy 2023年第4期11卷 1235-1246页

作者： Yang liu yanlei Zhao Lei Wang Chen Fang Bangpeng Xie Laixi Cui School of Electrical and Electronic Technology Shandong University of TechnologyZiboChina State Grid Shanghai Electric Power Research Institute ShanghaiChina State Grid Shanghai Pudong Electric Power Supply Company ShanghaiChina

High-impedance faults(HIFs)in distribution networks may result in fires or electric shocks.However,considerable difficulties exist in HIF detection due to low-resolution measurements and the considerably weaker time-frequency characteristics.This paper presents a novel HIF detection method using synchronized current information.The method consists of two stages.In the first stage,joint key characteristics of the system are extracted with the minimal system prior knowledge to identify the global optimal micro-phase measurement unit(μPMU)placement.In the second stage,the HIF is detected through a multivariate Jensen-Shannon divergence similarity measurement using high-resolution time-synchronized data inμPMUs in a high-noise environment.l2,1 principal component analysis(PCA),i.e.,PCA based on the l2,1 norm,is applied to an extracted system state and fault features derived from different resolution data in both stages.An economic observability index and HIF criteria are employed to evaluate the performance of placement method and to identify HIFs.Simulation results show that the method can reliably detect HIFs with reasonable detection accuracy in noisy environments.

关键词： High-impedance fault micro-phase measurement unit fault detection distribution network optimal placement

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ROS2 Real-time Performance Optimization and Evaluation

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 36-50页

作者： yanlei Ye Zhenguo Nie Xinjun liu Fugui Xie Zihao Li Peng Li State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Lab of Precision/Ultra-Precision Manufacturing Equipments and Control Tsinghua UniversityBeijing 100084China

Real-time interaction with uncertain and dynamic environments is essential for robotic systems to achieve functions such as visual perception,force interaction,spatial obstacle avoidance,and motion planning.To ensure the reliability and determinism of system execution,a flexible real-time control system architecture and interaction algorithm are required.The ROS framework was designed to improve the reusability of robotic software development by providing a distributed structure,hardware abstraction,message-passing mechanism,and application prototypes.Rich ecosystems for robotic development have been built around ROS1 and ROS2 architectures based on the Linux system.However,because of the fairness scheduling principle of the default Linux system design and the complexity of the kernel,the system does not have real-time computing.To achieve a balance between real-time and non-real-time computing,this paper uses the transmission mechanism of ROS2,combines it with the scheduling mechanism of the Linux operating system,and uses Preempt_RT to enhance the real-time computing of ROS1 and ROS2.The real-time performance evaluation of ROS1 and ROS2 is conducted from multiple perspectives,including throughput,transmission mode,QoS service quality,frequency,number of subscription nodes and EtherCAT master.This paper makes two significant contributions:firstly,it employs Preempt_RT to optimize the native ROS2 system,effectively enhancing the real-time performance of native ROS2 message transmission;secondly,it conducts a comprehensive evaluation of the real-time performance of both native and optimized ROS2 systems.This comparison elucidates the benefits of the optimized ROS2 architecture regarding real-time performance,with results vividly demonstrated through illustrative figures.

关键词： ROS Real-time system optimization Preempt_RT Real-time performance evaluation of ROS2

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Mesoscale structures and mechanisms in ionic liquids

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Particuology 2020年第1期18卷 55-64页

作者： Xiaomin liu Xiaoqian Yao yanlei Wang Suojiang Zhang School of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071ShandongChina Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex SystemsKey Laboratory of Green Process and EngineeringInstitute of process EngineeringChinese Academy of SciencesBeijing 100190China

Ionic liquids(ILs)have attracted intensive attention and have been used widely in many applications because of their diversified properties,which are caused by the special structure of the ILs.Ionic clusters are one of the typical structures that exist widely in the IL system.They are stable under certain conditions and change under other conditions.Ionic clusters are a typical mesoscale phenomenon in mesoscience.In this review,we summarize our recent progress related to ionic clusters,including the ionic-cluster structure,changing mechanisms,and their effect on the physicochemical properties.IL cluster investigation based on mesoscience is very important,will provide new insight into the structures and properties of ILs,and will boost further exploration of IL applications.

关键词： Ionic liquid Mesoscale structure Ionic cluster

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Roughness correction method for salinity remote sensing using combined active/passive observations

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Acta Oceanologica Sinica 2021年第11期40卷 189-195页

作者： Wentao Ma Guihong liu Yang Yu yanlei Du State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101China The Key Laboratory for Earth Observation of Hainan Province Sanya 572029China

Roughness-induced emission from ocean surfaces is one of the main issues that affects the retrieval accuracy of sea surface salinity remote sensing.In previous studies,the correction of roughness effect mainly depended on wind speeds retrieved from scatterometers or those provided by other means,which necessitates a high requirement for accuracy and synchronicity of wind-speed measurements.The aim of this study is to develop a novel roughness correction model of ocean emissivity for the salinity retrieval application.The combined active/passive observations of normalized radar cross-sections(NRCSs)and emissivities from ocean surfaces given by the L-band Aquarius/SAC-D mission,and the auxiliary wind directions collocated from the National Centers for Environmental Prediction(NCEP)dataset are used for model development.The model is validated against the observations and the Aquarius standard algorithms of roughness-induced emissivity correction.Comparisons between model computations and measurements indicate that the model has better accuracy in computing wind-induced brightness temperature in the upwind/downwind directions or for the surfaces with smaller NRCSs,which can be better than 0.3 K.However,for crosswind directions and larger NRCSs,the model accuracy is relatively low.A model using HH-polarized NRCSs yields better accuracy than that using VV-polarized ones.For a fair comparison to the Aquarius standard algorithms using wind speeds retrieved from multi-source data,the maximum likelihood estimation is employed to produce results combining our model calculations and those using other sources.Numerical simulations show that combined results basically have higher accuracy than the standard algorithms.

关键词： salinity remote sensing roughness correction Aquarius satellite active/passive

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Dual-targeted lung cancer therapy via inhalation delivery of UCNP-siRNA-AS1411 nanocages

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Cancer Biology & Medicine 2022年第7期19卷 1047-1060页

作者： Yu Han Yuming Yang Qiuyang Sun Bin Li Caixia Yue Yanlei Liu Jesús M.de la Fuente Daxiang Cui Institute of Nano Biomedicine and Engineering Key Laboratory for Thin Film and Microfabrication Technology of the Ministry of EducationShanghai Engineering Research Center for Intelligent Diagnosis and Treatment InstrumentDepartment of Instrument Science&EngineeringSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China National Engineering Center for Nanotechnology Collaborative Innovational Center for System BiologyShanghai 200241China Department of Neurosurgery Xinhua HospitalShanghai Jiaotong University School of MedicineShanghai 200092China School of Biomedical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Instituto de Nanociencia de Aragon(INA) Universidad de ZaragozaZaragoza 50018Spain

Objective:Although great progress has been made in the field of siRNA gene therapy,safe,efficient,and targeted delivery of siRNA are still major challenges in siRNA therapeutics.Methods:We developed an up-conversion nanoparticle-based nanocage system.This system protected the siRNA from being degraded by nucleases in organisms and selectively delivered the siRNAs to the tumor sites,due to modifications of targeted molecules on the surfaces of nanocages and local inhalation.Results:The siRNAs delivered by the up-conversion nanoparticle nanocages were protected from degradation in transit to the tumor sites,where they accumulated.Compared with the passive target and control groups,the up-conversion nanoparticles based on the nanocage system showed a tumor suppressive effect after approximately 3 weeks of treatment.Conclusions:The up-conversion nanoparticle nanocages efficiently delivered vascular endothelial growth factor siRNAs to tumor sites.Mice with lung tumors treated with tumors targeting up-conversion nanoparticle nanocages showed steady body weight changes,high tumor inhibition ratios,and longer survival times.

关键词： Nanomaterials VEGF siRNA lung cancer gene therapy siRNA delivery

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Realization of Oriented and Nanoporous Bismuth Chalcogenide Layers via Topochemical Heteroepitaxy for Flexible Gas Sensors

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Research 2022年第4期2022卷 211-221页

作者： Zhiwei Wang Jie Dai Jian Wang Xinzhe Li Chengjie Pei Yanlei Liu Jiaxu Yan Lin Wang Shaozhou Li Hai Li Xiaoshan Wang Xiao Huang Wei Huang Institute of Advanced Materials(IAM) Nanjing Tech University(NanjingTech)30 South Puzhu RoadNanjing 211816China Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics(IFE)and Xi'an Institute of Biomedical Materials EngineeringNorthwestern Polytechnical University127 West Youyi RoadXi'an 710072China Key Laboratory for Organic Electronic e Information Displays(KLOEID)and Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing 210023China

Most van der Waals two-dimensional(2D)materials without surface dangling bonds show limited surface activities except for their edge sites.Ultrathin Bi_(2)Se_(3),a topological insulator that behaves metal-like under ambient conditions,has been overlooked on its surface activities.Herein,through a topochemical conversion process,ultrathin nanoporous Bi_(2)Se_(3) layers were epitaxially deposited on BiOCl nanosheets with strong electronic coupling,leading to hybrid electronic states with further bandgap narrowing.Such oriented nanoporous Bi_(2)Se_(3) layers possessed largely exposed active edge sites,along with improved surface roughness and film forming ability even on inkjet-printed flexible electrodes.Superior room-temperature NO_(2) sensing performance was achieved compared to other 2D materials under bent conditions.Our work demonstrates that creating nanoscale features in 2D materials through topochemical heteroepitaxy is promising to achieve both favorable electronic properties and surface activity toward practical applications.

关键词： chemical bonds roughness

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