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Trailing (L5) Neptune Trojans: 2004 KV18 and 2008 LC18

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Research in Astronomy and Astrophysics 2012年第11期12卷 1549-1562页

作者： Pu Guan li-Yong zhou jian li Department of Astronomy & Key Laboratory of Modem Astronomy and Astrophysics in Ministryof Education Nanjing University Nanjing 210093 China

The population of Neptune Trojans is believed to be bigger than that of Jupiter Trojans and that of asteroids in the main belt, although only eight members of this distant asteroid swarm have been observed up to now. Six leading Neptune Trojans around the Lagrange point L4 discovered earlier have been studied in detail, but two trailing ones found recently around the L5 point, 2004 KV18 and 2008 LC18, have not yet been investigated. We report our investigations on the dynamical behaviors of these two new Neptune Trojans. Our calculations show that the asteroid 2004 KV18 is a temporary Neptune Trojan. Most probably, it was captured into the trailing Trojan cloud no earlier than 2.03 ×105 yr ago, and it will not maintain this position later than 1.65 × 105 yr in the future. Based on the statistics from our orbital simulations, we ar- gue that this object is more like a scattered Kuiper belt object. By contrast, the orbit of 2008 LC18 is much more stable. Among the clone orbits spreading within the orbital uncertainties, a considerable portion of clones may survive on the L5 tadpole orbits for 4 Gyr. The strong dependence of the stability on the semimajor axis and resonant angle suggests that further observations are badly required to constrain the orbit in the stable region. We also discuss the implications of the existence and dynamics of these two trailing Trojans over the history of the solar system.

关键词： solar system general -- Kuiper belt -- asteroids -- methods numerical

linear Correlations between Peak Frequency of Gyrosynchrotron Spectrum and Photosphere Magnetic Fields

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Chinese Journal of Astronomy and Astrophysics 2007年第4期7卷 487-495页

作者： Ai-Hua zhou jian-Ping li Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008

The gyrosynchrotron spectra are computed in a nonuniform magnetic field case, taking into account the self- and gyroresonance absorption. It is found that the peak frequency νp of the gyrosynchrotron spectrum systematically increases with the increasing photosphere magnetic field strength B0 and increasing viewing angle θ. It is also found for the first time that there are good positive linear correlations between νp and B0, and between log νp and log θ, with linear correlation coefficient 0.99 between νp and B0 and 0.95 between log νp and log θ. We apply the correlations to analyze two burst events observed with OVSA and find that the evolution tendencies of the photosphere magnetic field strength B0 estimated from the above expression are comparable with the observational results of SOHO/MDI. We also give a comparison of the diagnostic results of coronal magnetic field strength in both uniform and nonuniform source models.

关键词： Sun: flare - sun: radio emission - Sun: magnetic field

High frequency of thrombocytopenia in patients with acute-on-chronic liver failure treated with linezolid

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Hepatobiliary & Pancreatic Diseases International 2015年第3期14卷 287-292页

作者： Yi-Min Zhang Wei Yu Ning zhou jian-zhou li li-Chen Xu Zhong-Yang Xie Ying-Feng Lu Lan-Juan li State Key Laboratory for Diagnosis and Treatment of Infectious Diseases Department of Infectious Diseases the First Affiliated Hospital Zhejiang University School of Medicine Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases

BACKGROUND： linezolid is an effective antibiotic reagent for Gram-positive bacterial infection; its most common side effect is thrombocytopenia. However, the incidence of throm- bocytopenia in patients with acute-on-chronic liver failure （ACLF） who underwent linezolid therapy was unclear. The present study was to evaluate the incidence of thrombocyto- penia in ACLF and non-ACLF patients treated with linezolid and the risk factors of thrombocytopenia in these patients.

关键词： acute-on-chronic liver failure linezolid thrombocytopenia

From molecule to cell:the expanding frontiers of plant immunity

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Journal of Genetics and Genomics 2024年第7期51卷 680-690页

作者： Lei li Jing liu jian-Min zhou Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Hainan Yazhou Bay Seed Laboratory SanyaHainan 572025China

In recent years,the field of plant immunity has witnessed remarkable *** the co-evolution between plants and pathogens,plants have developed a wealth of intricate defense mechanisms to safeguard their *** identified immune receptors have added unexpected complexity to the surface and intracellular sensor networks,enriching our understanding of the ongoing plant–pathogen *** the molecular mechanisms of resistosome shapes our understanding of these mysterious molecules in plant ***,technological innovations are expanding the horizon of the plant–pathogen battlefield into spatial and temporal *** the development provides new opportunities for untangling the complex realm of plant immunity,challenges remain in uncovering plant immunity across spatiotemporal dimensions from both molecular and cellular levels.

关键词： Plant immunity Calcium Spatiotemporal Biomolecular condensate Immune receptor Resistosome

Rockburst prediction and prevention in underground space excavation

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Underground Space 2024年第1期14卷 70-98页

作者： jian zhou Yulin Zhang Chuanqi li Haini He Xibing li School of Resources and Safety Engineering Central South UniversityChangsha 410083China Laboratory 3SR CNRS UMR 5521Grenoble Alpes UniversityGrenoble 38000France

The technical challenges associated with deep underground space activities have become increasingly *** these challenges,one major concern is the assessment of rockburst risks and the instability of rock *** research has been conducted by numerous scholars to mitigate the risks and prevent occurrences of rockburst through various assessment *** incidents commonly occur during the excavation of hard rock in underground environments,posing severe threats to personnel safety,equipment integrity,and operational ***,it is crucial to systematically document real cases of rockburst,allowing for a comprehensive understanding of the underlying mechanisms and triggering *** understanding will contribute to the advancement of rockburst prediction and prevention *** selection of an appropriate rockburst assessment method is a fundamental aspect in underground ***,there is a limited number of studies that summarize and compare different prediction and prevention methods of *** paper aims to address this gap by analyzing global trends using CiteSpace software since *** discusses rockburst classification and characteristics,comprehensively reviews research findings related to rockburst prediction,including empirical,simulation,mathematical modeling,and microseismic monitoring ***,the paper presents a compilation of current rockburst prevention ***,the paper emphasizes the significance of control strategies,which provide key insights into the effective utilization of stored energy within ***,the paper concludes by suggesting six directions for implementing intelligent management techniques to mitigate hazards during underground operations and reduce the probability of rockburst incidents.

关键词： Rockburst Underground space Scientometric analysis Characteristic analysis Rockburst prediction Rockburst prevention

Evolutionary mechanisms and practical significance of reproductive success and clonal diversity in unisexual vertebrate polyploids

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Science China(life Sciences) 2024年第3期67卷 449-459页

作者： Meng Lu li zhou jian-Fang Gui State Key Laboratory of Freshwater Ecology and Biotechnology Hubei Hongshan Laboratorythe Innovation Academy of Seed DesignInstitute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China

Unisexual reproduction is generally relevant to polyploidy, and unisexual vertebrates are often considered an evolutionary “dead end” due to the accumulation of deleterious mutations and absence of genetic diversity. However, some unisexual polyploids have developed strategies to avoid genomic decay, and thus provide ideal models to unveil unexplored evolutionary mechanisms, from the reproductive success to clonal diversity creation. This article reviews the evolutionary mechanisms for overcoming meiotic barrier and generating genetic diversity in unisexual vertebrates, and summarizes recent research advancements in the polyploid Carassius complex. Gynogenetic gibel carp(Carassius gibelio) is a unique amphitriploid that has undergone a recurrent autotriploidy and has overcome the bottleneck of triploid sterility via gynogenesis. Recently, an efficient strategy in which ploidy changes, including from amphitriploid to amphitetraploid, then from amphitetraploid to novel amphitriploid, drive unisexual-sexual-unisexual reproduction transition and clonal diversity has been *** on this new discovery, multigenomic reconstruction biotechnology has been used to breed a novel strain with superior growth and stronger disease resistance. Moreover, a unique reproduction mode that combines both abilities of ameiotic oogenesis and sperm-egg fusion,termed as ameio-fusiongensis, has been discovered, and it provides an efficient approach to synthesize sterile allopolyploids. In order to avoid ecological risks upon escape and protect the sustainable property rights of the aquaculture seed industry, a controllable fertility biotechnology approach for precise breeding is being developed by integrating sterile allopolyploid synthesis and gene-editing *** review provides novel insights into the origin and evolution of unisexual vertebrates and into the attempts being made to exploit new breeding biotechnologies in aquaculture.

关键词： unisexual vertebrates polyploidy reproduction transition clonal diversity precise breeding genomic reconstruction controllable fertility

A comprehensive comparison of different regression techniques and nature-inspired optimization algorithms to predict carbonation depth of recycled aggregate concrete

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 30-50页

作者： Bin XI Ning ZHANG Enming li Jiabin li jian zhou Pablo SEGARRA Department of Civil and Environmental Engineering Politecnico Di MilanoMilano 20133Italy Leibniz Institute of Ecological Urban and Regional Development(IOER) Dresden 01217Germany Universidad Politécnica de Madrid-ETSI Minas y Energía Madrid 28003Spain Department of Civil Engineering KU Leuven CampusBrugge 8200Belgium School of Resources and Safety Engineering Central South UniversityChangsha 410083China

The utilization of recycled aggregates(RA)for concrete production has the potential to offer substantial environmental and economic ***,RA concrete is plagued with considerable durability concerns,particularly *** advance the application of RA concrete,the establishment of a reliable model for predicting the carbonation is *** the one hand,concrete carbonation is a long and slow process and thus consumes a lot of time and energy to *** the other hand,carbonation is influenced by many factors and is hard to *** this,this paper proposes the use of machine learning techniques to establish accurate prediction models for the carbonation depth(CD)of RA *** types of regression techniques and meta-heuristic algorithms were employed to provide more alternative predictive *** was found that the best prediction performance was obtained from extreme gradient boosting-multi-universe optimizer(XGB-MVO)with R^(2) value of 0.9949 and 0.9398 for training and testing sets,***-MVO was used for evaluating physical laws of carbonation and it was found that the developed XGB-MVO model could provide reasonable predictions when new data were *** also showed better generalization capabilities when compared with different models in the ***,this paper emphasizes the need for sustainable solutions in the construction industry to reduce its environmental impact and contribute to sustainable and low-carbon economies.

关键词： recycled aggregate concrete carbonation depth nature-inspired optimization algorithms extreme gradient boosting technique parametric analysis

Spherical Confinement Generates Entropic Force to Accelerate Polymer Chain Detachment

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Chinese Journal of Polymer Science 2024年第3期42卷 407-416,I0010页

作者： Yu-Shan Zheng jian-Ping zhou Yan Xu Kai li Mechanical Engineering Xinjiang UniversityUrumqi 830002China

To understand the dynamic process of polymer detachment, it is necessary to determine the mean detachment time of a single breakable link, which is modeled as a spring. Normally, this time can be viewed as the escape of a Brownian particle from the potential well of the spring. However, as the free dangling length of the polymer chain increases, the conformational entropy of the chain is affected by geometric confinement. It means that the wall exerts a repulsive force on the chain, resulting in accelerated link detachment from a macroscopic perspective. In this work, we investigate the effect of entropy on the detachment rate in the case where the substrate is spherical. We demonstrate that spherical confinement accelerates chain detachment both inside and outside the sphere. An analytical expression for the mean detachment time of breakable links is given, which includes an additional pre-factor that is related to the partition function. Additionally, we analyze the expressions for entropic forces inside the sphere, outside the sphere, and on a flat wall, comparing their magnitudes to explain the difference in mean detachment time.

关键词： Polymer detachment Breakable link Entropic force Mean first passage time

Emergent Geometry of KP Hierarchy

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Acta Mathematica Sinica,English Series 2024年第1期40卷 3-25页

作者： jian zhou Department of Mathematical Sciences Tsinghua UniversityBeijng 100084P.R.China

We explain how to construct a quantum deformation of a spectral curve associated to a tau-function of the KP *** construction is applied to Witten-Kontsevich tau-function to give a natural explanation of some earlier ... 详细信息

关键词： KP hierarchy tau-functions spectral curves