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Recent advances in mammalian reproductive biology

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Science China(Life Sciences) 2020年第1期63卷 18-58页

作者： Lu Wen Qiang liu Jingjing Xu Xixi liu Chaoyi Shi Zuwei Yang Yili Zhang Hong Xu jiang liu Hui Yang Hefeng Huang Jie Qiao Fuchou Tang Zi-jiang Chen Beijing Advanced Innovation Center for Genomics Department of Obstetrics and Gynecology Third HospitalCollege of Life SciencesPeking UniversityBeijing 100871China National Research Center for Assisted Reproductive Technology and Reproductive Genetics Jinan 250021China International Peace Maternity and Child Health Hospital School of MedicineShanghai Jiao Tong UniversityShanghai Key Laboratory of Embryo Original DiseasesShanghai 200030China Institute of Neuroscience State Key Laboratory of NeuroscienceKey Laboratory of Primate NeurobiologyCAS Center for Excellence in Brain Science and Intelligence TechnologyShanghai Research Center for Brain Science and Brain-Inspired IntelligenceShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China CAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China

Reproductive biology is a uniquely important topic since it is about germ cells, which are central for transmitting genetic information from generation to generation. In this review, we discuss recent advances in mammalian germ cell development,including preimplantation development, fetal germ cell development and postnatal development of oocytes and sperm. We also discuss the etiologies of female and male infertility and describe the emerging technologies for studying reproductive biology such as gene editing and single-cell technologies.

关键词： preimplantation fetal germ cell oogenesis spermatogenesis female infertility male infertility gene editing single-cell sequencing

Study on key technologies of GNSS-based train state perception for traincentric railway signaling

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High-Speed Railway 2023年第1期1卷 47-55页

作者： Baigen Cai Jingnan liu Xurong Dong jiang liu School of Computer and Information Technology Bejing Jiaotong UniversityBeijing 100044China Frontiers Science Center for Smart High-speed Railway System Beijing Jiaotong UniversityBeijing 100044China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China GNSS Research Center Wuhan UniversityWuhan 430079China Space Engineering University Beijing 101416China

The application of Global Navigation Satellite Systems(GNSSs)in the intelligent railway systems is rapidly developing all over the *** the GNSs-based train positioning and moving state perception,the autonomy and flexibility of a novel train control system can be greatly enhanced over the existing solutions relying on the track-side *** the safety critical features of the railway signaling applications,the GNSS stand-alone mode may not be sufficient to satisfy the practical *** this paper,the key technologies for applying GNSS in novel train-centric railway signaling systems are investigated,including the multi-sensor data fusion,Virtual Balise(VB)capturing and messaging,train integrity monitoring and system performance *** to the practical characteristics of the novel train control system under the moving block mode,the details of the key technologies are *** demonstration results of a novel train control system using the presented technologies under the practical railway operation conditions are presented to illustrate the achievable performance feature of autonomous train state perception using BeiDou Navigation Satellite System(BDS)and related *** reveals the great potentials of these key technologies in the next generation train control system and other GNSS-based railway implementations.

关键词： Railway signaling Train control Global Navigation Satellite System Sensor data fusion Virtual Balise Train integrity Performance evaluation

Adaptive scheme based on status feedback for virtual network mapping

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The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 87-94页

作者： LU Bo HUANG Tao WANG Zhen-kai CHEN Jian-ya liu Yun-jie liu jiang Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Network virtualization is considered as a powerful way to deploy different network architectures and protocols over a shared physical infrastructure. Virtual network （VN） embedding plays an important role in the network virtualization environment. Virtual network embedding is mainly about mapping virtual nodes and virtual links onto the physical network resources efficiently. However, load balancing of substrate network has not received much consideration. This paper proposes an adaptive virtual network mapping algorithm based on status feedback. The main contribution is to embed the virtual network requests according to the current load distribution of substrate network. This adaptive algorithm differentiates the residual bandwidth of substrate links and takes full advantage of the multi-path to improve the load balancing of the substrate network. Simulation experiments show that the proposed algorithm improves the load distribution of substrate network distinctly while reducing the average substrate link stress significantly.

关键词： network virtualization virtual network embedding load balancing

Design of in-network caching scheme in CCN based on grey relational analysis

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 1-8页

作者： CUI Xian-dong HUANG Tao liu jiang LI Li CHEN Jian-ya liu Yun-jie State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Future Network Industry Innovation Center of China

In-network caching is one of the most important issues in content centric networking （CCN）, which may extremely influence the performance of the caching system. Although much work has been done for in-network caching scheme design in CCN, most of them have not addressed the multiple network attribute parameters jointly during caching algorithm design. Hence, to fill this gap, a new in-network caching based on grey relational analysis （GRA） is proposed. The authors firstly define two newly metric parameters named request influence degree （RID） and cache replacement rate, respectively. The RID indicates the importance of one node along the content delivery path from the view of the interest packets arriving The cache replacement rate is used to denote the caching load of the node. Then combining hops a request traveling from the users and the node traffic, four network attribute parameters are considered during the in-network caching algorithm design. Based on these four network parameters, a GRA based in-network caching algorithm is proposed, which can significantly improve the performance of CCN. Finally, extensive simulation based on ndnSIM is demonstrated that the GRA-based caching scheme can achieve the lower load in the source server and the less average hops than the existing the betweeness （Betw） scheme and the ALWAYS scheme.

关键词： CCN in-network caching request influence degree cache replacement rate grey relational analysis

Packing,compressibility,and crushability of rockfill materials with polydisperse particle size distributions and implications for dam engineering

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Water Science and Engineering 2022年第4期15卷 358-366页

作者： Chao-min Shen Si-hong liu liu-jiang Wang Ji-du Yu Hao Wei Ping Wu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China International Joint Laboratory of Long-term Behaviour&Environmentally Friendly Rehabilitation Technologies on Dams Hohai UniversityNanjing 210098China China Railway Water Conservancy&Hydropower Planning and Design Group Co.Ltd. Nanchang 330029China

In rockfill dam engineering,particle breakage of rockfill materials is one of the major factors resulting in dam *** this study,one-dimensional compression tests on a series of coarse granular materials with artificially-graded particle size distributions(PSDs)were carried *** tests focused on understanding the role of initial PSDs in the dense packing density,compressibility and crushability of coarse granular *** effects of fractal dimension(D)and size polydispersity(θ)of PSDs were quantitatively *** different loading stages were identified from the logarithms of the stress-strain relationships,with the turning point marked as the yield stress.A similar effect of initial PSDs was observed on the packing density and low-pressure modulus of coarse granular *** packing density and low-pressure modulus increased monotonically withθ,and their peak values were attained at a D value of approximately ***,there was no unique correspondence between the dense packing density and low-pressure *** particle breakage was influenced differently by the initial PSDs,and it decreased with the values of D andθ.The emergence of the unique ultimate state was also identified from both the compression curves and PSDs of the samples after the *** potential implications of the test results in the design of both low and high rockfill dams were also demonstrated.

关键词： Rockfill materials Packing density Compressibility Particle breakage Rockfill dam

Effect of health education based on information-motivationbehavioral skills model on patients with unilateral vestibular dysfunction

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World Journal of Clinical Cases 2024年第5期12卷 903-912页

作者： Qiong Shi Ruo-Jun Wu jiang liu Department of Neurology Wuahan Fourth HospitalWuhan 430000Hubei ProvinceChina Department of Critical Care Medicine Wuhan No.1 HospitalWuhan 430033Hubei ProvinceChina

BACKGROUND Vestibular dysfunction(VH)is a common concomitant symptom of late peri-pheral vestibular lesions,which can be trauma,poisoning,infection,heredity,and neurodegeneration,but about 50%of the causes are *** study uses the information-motivation-behavioral skills(IMB)model for health education,effectively improve the quality of life,increase their self-confidence,reduce anxiety and depression,and effectively improve the psychological state of *** To explore the effect of health education based on the IMB model on the degree of vertigo,disability,anxiety and depression in patients with unilateral vestibular *** The clinical data of 80 patients with unilateral vestibular hypofunction from January 2019 to December 2021 were selected as the retrospective research objects,and they were divided into the control group and the observation group with 40 cases in each group according to different nursing *** them,the control group was given routine nursing health education and guidance,and the observation group was given health education and guidance based on the IMB *** changes in self-efficacy,anxiety and depression,and quality of life of patients with unilateral VH were compared between the two *** There was no significant difference in General Self-Efficacy Scale(GSES)scale scores between the two groups of patients before nursing(P>0.05),which was comparable;after nursing,the GSES scale scores of the two groups were higher than those before *** nursing group was higher than the control group,and the difference was statistically significant(P0.05).After nursing,the HADS score,anxiety,and depression subscale scores of the two groups of patients were lower than those before nursing,and the nursing group was lower than the co

关键词： Information-motivation-behavioral skills model Health education Vestibular function Quality of life Selfefficacy

Regulation of the arachidonic acid-stimulated respiratory burst in neutrophils by intra-cellular and extracellular calcium

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Chinese Science Bulletin 2001年第4期46卷 314-317页

作者： Shaokun Chuai Tianhui Hu jiang liu Xun Shen Chinese Acad Sci Inst Biophys Beijing 100101 Peoples R China

The respiratory burst is an important physiological function of the neutrophils in killing the bacteria invading in human body. We used chemiluminescence method to measure the exogenous arachidonic acid-stimulated respiratory burst, and measured the cytosolic free calcium concentration in neutrophils by the fluorescence method. It was found that, on one hand, the arachidonic acid-stimulated respiratory burst was enhanced by elevating the cytosolic free calcium concentration in neutrophils with a potent endomembrane Ca2+-ATPase inhibitor, Thapsgargin; on the other hand, chelating the intracellular or extracellular calcium by EGTA or BAPTA inhibited the respiratory burst. Results showed that calcium plays an important regulatory role in the signaling pathway involved in the exogenous arachidonic acid-stimulated respiratory burst of neutrophils.

关键词： arachidonic acid neutrophils respiratory burst chemi-luminescence intracellular calcium extracellular calcium.

Resource Allocation and User Association for HTTP Adaptive Streaming in Heterogeneous Cellular Networks with Small Cells

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China Communications 2016年第9期13卷 1-11页

作者： jiang liu State Key Laboratory of Networking and Switching Technology Beijing University of Post and TelecommunicationsBeijing 100876China Department of Systems and Computer Engineering Carleton UniversityOttawaONCanada Beijing Advanced Innovation Center for Future Internet Technology Beijing 100124China

Video streaming,especially hypertext transfer protocol based(HTTP) adaptive streaming(HAS) of video,has been expected to be a dominant application over mobile networks in the near future,which brings huge challenge for the mobile *** some works have been done for video streaming delivery in heterogeneous cellular networks,most of them focus on the video streaming scheduling or the caching strategy *** problem of joint user association and rate allocation to maximize the system utility while satisfying the requirement of the quality of experience of users is largely *** this paper,the problem of joint user association and rate allocation for HTTP adaptive streaming in heterogeneous cellular networks is studied,we model the optimization problem as a mixed integer programming *** to reduce the computational complexity,an optimal rate allocation using the Lagrangian dual method under the assumption of knowing user association for BSs is first *** we use the many-to-one matching model to analyze the user association problem,and the joint user association and rate allocation based on the distributed greedy matching algorithm is ***,extensive simulation results are illustrated to demonstrate the performance of the proposed scheme.

关键词： heterogeneous cellular networks user association rate allocation http adaptive streaming matching algorithm

Low-dimensional chaos and fractal properties of long-term sunspot activity

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Research in Astronomy and Astrophysics 2014年第1期14卷 104-112页

作者： Shuang Zhou Yong Feng Wen-Yuan Wu Yi Li jiang liu Chongqing Key Laboratory of Automated Reasoning and Cognition Chongqing Institute of Green and Intelligent TechnologyChinese Academy of Sciences University of Chinese Academy of Sciences

Two primary solar-activity indicators- sunspot numbers （SNs） and sunspot areas （SAs） in the time interval from November 1874 to December 2012 - are used to determine the chaotic and fractal properties of solar activity. The results show that （1） the long-term solar activity is governed by a low-dimensional chaotic strange attractor, and its fractal motion shows a long-term persistence on large scales; （2） both the fractal dimension and maximal Lyapunov exponent of SAs are larger than those of SNs, implying that the dynamical system of SAs is more chaotic and complex than SNs; （3） the predictions of solar activity should only be done for short- to mid-term behaviors due to its intrinsic complexity; moreover, the predictability time of SAs is obviously smaller than that of SNs and previous results.

关键词： methods: data analysis -- Sun: activity -- Sun: sunspots