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Transient Phenomena from Gas Erupting Neutron Stars

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Research in Astronomy and Astrophysics 2022年第1期22卷 189-191页

作者： hui-Quan Li jian-Cheng Wang Yunnan Observatories Chinese Academy of Sciences650216 KunmingChina Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences650216 KunmingChina Center for Astronomical Mega-Science Chinese Academy of Sciences100012 BeijingChina

Starquakes probably occur in rapidly spinning or ultra high field neutron stars. In this article, we argue that highly compressed gas containing electron–positron pairs could evaporate and erupt from inside the neutron star when a crack forms and then heals during a starquake. Under the influence of the existing oscillation modes of the star, the crack may have sufficiently large size and long lifetime. An appropriate amount of gas can erupt into the magnetosphere with relativistic and nearly uniform velocity, producing various transient and bursting phenomena.

关键词： stars:neutron stars:magnetars (stars:)pulsars:general

On the correction of the boundary deficiency in SPH for the frictional contact simulation

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Science China(Technological Sciences) 2014年第1期57卷 86-100页

作者： WANG jian HUA hui GU ChongShi National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University College of Water Conservancy and Hydropower Engineering Hohai University

Smoothed particle hydrodynamics(SPH)is a mesh-free method which is powerful for large deformation computation of ***,the algorithm for the simulation of frictional contact which is common in geotechnical engineering is still quite immature due to the boundary *** this study,the cause of boundary deficiency in the SPH simulation for frictional contact is ***,based on mathematical derivation,the method to correct boundary deficiency related to frictional contact is discussed theoretically,where the frictional contact algorithm is established by dividing the computational domain into several subdomains according to the existing contact boundaries and by using contact forces as bridges of these subdomains to fulfil problem solving,and the value of correction coefficient is obtained by comparing the SPH outcome of the contact particles with that calculated through Newton’s second law of *** the same time,from the perspective of numerical computation,an optimized value for the correction coefficient is proposed,and a thorough investigation is performed on the cubic spline kernel function and quintic spline kernel function,whose correction coefficients are found to be 2.0 and[2.0,2.16],***,numerical tests are carried out to verify the proposed *** outcome of the study is helpful to providing theoretical support for the research of frictional contact simulation within the framework of SPH.

关键词： smoothed particle hydrodynamics (SPH) frictional contact boundary deficiency correction

Identifying indigenous tree species for land reforestation,forest restoration, and plantation transformation on Hainan Island, China

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Journal of Mountain Science 2018年第11期15卷 2433-2444页

作者： WANG jian-jun MENG Jing-hui Key Laboratory for Forest Resources and Ecosystem Processes of Belling Belling Forestry University Beijing 100083 China

Selecting suitable species is the most important issue for bare land reforestation, degraded secondary forest restoration, and single-species plantation transformation. However, little information has been documented related to tree species selection for these silvicultural endeavors on tropical Hainan Island of Southern China. The present study employed Baisha County, the ecological core area of Hainan Island, as a case study area. We initially inventoried a slightly disturbed primary forest and attempted to produce diameter distribution curves for each tree species. Second, the tree species were classified into shade intolerant, opportunist, and shade tolerant species based on shape of their diameter distribution curves. Third, market value was determined for each tree species based on published literature and on-site investigations at local wood trading companies. Totally 118 tree species were encountered in the inventoried forest and 13 tree species present were finally identified as potential tree species for our silvicultural endeavor on Hainan Island, of which 3 species are shade intolerant, 5 species are opportunist and 5 species are shade tolerant. Additionally, we also selected 12 tree species that were not in the inventoried forest but were extremely economically valuable and ecologically important. This study should contribute to the formulation of a sustainable forest management strategy on Hainan Island and the methodology might be replicated in other tropical region where suitable species also need to be identified for silvicultural endeavor.

关键词： Diameter distribution curves Primary forest Shade intolerant Opportunist species Shade tolerant Forest management

Ruin Probabilities for a Two-Dimensional Perturbed Risk Model with Stochastic Premiums

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Acta Mathematicae Applicatae Sinica 2016年第4期32卷 1053-1066页

作者： jian-hua CHENG De-hui WANG School of Mathematics Jilin University

In this paper, we consider a two-dimensional perturbed risk model with stochastic premiums and certain dependence between the two marginal surplus processes. We obtain the Lundberg-type upper bound for the infinite-time ruin probability by martingale approach, discuss how the dependence affects the obtained upper bound and give some numerical examples to illustrate our results. For the heavy-tailed claims case, we derive an explicit asymptotic estimation for the finite-time ruin probability.

关键词： two-dimensional risk model ruin probability upper bound dependent risk asymptotic estimate

RNA silencing:From discovery and elucidation to application and perspectives

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Journal of Integrative Plant Biology 2022年第2期64卷 476-498页

作者： jian-Hua Zhao hui-Shan Guo State Key Laboratory of Plant Genomics Institute of Microbiologythe Chinese Academy of SciencesBeijing100101 China CAS Center for Excellence in Biotic Interactions University of the Chinese Academy of SciencesBeijing100049 China

RNA silencing(or RNA interference,RNAi)is a conserved mechanism for regulating gene expression in *** discovery of natural trans-kingdom RNAi indicated that small RNAs act as signaling molecules and enable communication between organisms in different *** phenomenon and potential mechanisms of trans-kingdom RNAi are among the most exciting research *** better understand trans-kingdom RNAi,we review the history of the discovery and elucidation of RNAi *** on canonical RNAi mechanisms,we summarize the major points of divergence around RNAi pathways in the main eukaryotes’kingdoms,including plants,animals,and *** review the representative incidents associated with the mechanisms and applications of trans-kingdom RNAi in crop protection,and discuss the critical factors that should be considered to develop successful trans-kingdom RNAi-based crop protection strategies.

关键词： crop protection gene expression RNA silencing small RNAs trans-kingdom RNAi

LIE SYMMETRIES AND CONSERVED QUANTITIES OF SECOND-ORDER NONHOLONOMIC MECHANICAL SYSTEM

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Applied Mathematics and Mechanics(English Edition) 2002年第9期23卷 1105-1110页

作者： FANG jian-hui(方建会) Department of Applied Physics University of Petroleum Dongying Shandong257061 P R China

The Lie symmetries and the conserved quantities of the second-order nonholonomic mechanical system are studied. Firstly, by using the invariance of the differential equation of motion under the infinitesimal tran, formations, the determining equations and the restriction equations of the Lie symmetries of the system are established, and the structure equation and the conservative quantities of the Lie symmetries are obtained. Secondly, the inverse problems of the Lie symmetries are studied. Finally, an example is given to illustrate the application of the result.

关键词： second-order nonholonomic system Lie symmetry conserved quantity

Clinical significance and prognostic value of tumor necrosis factor-α and dickkopf related protein-1 in ankylosing spondylitis

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World Journal of Clinical Cases 2020年第7期8卷 1213-1222页

作者： Jun-hui Xiong jian Liu jian Chen Department of Rheumatology Lishui People’s HospitalLishui 323000Zhejiang ProvinceChina

BACKGROUND Ankylosing spondylitis(AS)frequently occurs in people aged 30-45 years,and its prevalence is generally believed to be between 0.1%and 1.4%*** present,the“gold standard”for diagnosis of AS requires the provision of pelvic X-rays,which makes it more difficult to perform in population-based epidemiological ***,the identification of serological indicators related to the diagnosis,treatment,and prognosis of AS patients is of great *** To analyze the therapeutic,diagnostic significance and prognostic value of dickkopf-related protein-1(DKK-1)and tumor necrosis factor-α(TNF-α)in *** A total of 113 patients with active AS were selected as the research group,and 100 healthy subjects who underwent physical examination were selected as the control *** levels of DKK-1 and TNF-α in peripheral blood in the two groups were *** diagnostic and predictive values of DKK-1 and TNF-α for AS were analyzed with ROC curves,and the factors influencing AS recurrence were analyzed with COX *** Before treatment,the research group showed lower DKK-1 levels but higher TNF-αlevels than the control group(both aP<0.05).In the research group,DKK-1 was up-regulated and TNF-αwas down-regulated after 12 wk of treatment(aP<0.05).The area under the curve,sensitivity and specificity of DKK-1 combined with TNF-αfor diagnosing AS were 0.934,82.30%and 97.00%,*** treatment,the area under the curve,cutoff value,sensitivity and specificity of DKK-1 for predicting the curative effect were 0.825,68.42 pg/mL,73.68%and 80.00%,respectively,and those of TNF-αwere 0.863,32.79 ng/L,92.11%and 77.33%,***-1 and TNF-αlevels after treatment were closely related to the curative effect(aP<0.05).C-reactive protein,the Bath Ankylosing Spondylitis Disease Activity Index,DKK-1,and TNF-αwere risk factors for AS recurrence(aP<0.05).CONCLUSION DKK-1 and TNF-αare effective in the diagnosis and treatment of AS and are risk f

关键词： Dickkopf-related protein-1 Tumor necrosis factor-α Ankylosing spondylitis Diagnosis Prognosis Peripheral blood

Mesonic condensation in isospin matter under rotation

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Chinese Physics C 2020年第11期44卷 1-6页

作者： hui Zhang Defu Hou Jin-Feng liao Institute of Particle Physics(IOPP)and Key Laboratory of Quark and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China Guangdong Provincial Key Laboratory of Nuclear Science Institute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China Physics Department and Center for Exploration of Energy and Matter Indiana University2401 N Milo B.Sampson LaneBloomingtonIN 47408USA

We investigate mesonic condensation in isospin matter under *** the two-flavor NJL effective model in the presence of global rotation,we demonstrate two important effects of rotation on its phase structure:a rotational suppression of the scalar-channel condensates,in particular,the pion condensation region;and a rotational enhancement of the rho condensation region with vector-channel condensate.A new phase diagram for isospin matter under rotation is mapped out on the ω−μI plane where the three distinct phases,corresponding to the σ,π,ρ-dominated regions,respectively,are separated by a second-order line at low isospin chemical potential as well as a first-order line at high rotation and are further connected at a tri-critical point.

关键词： phase structure rotating isospin matter mesonic condensate

Electronic Structure of KFe_(2)Se_(2) from First-Principles Calculations

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Chinese Physics Letters 2011年第5期28卷 230-233页

作者： CAO Chao DAI jian-hui Condensed Matter Physics Group Department of PhysicsHangzhou Normal UniversityHangzhou 310036 Zhejiang Institute of Modern Physics Department of PhysicsZhejiang UniversityHangzhou 310027

Electronic structures and magnetic properties for iron-selenide KFe_(2)Se_(2) are studied by first-principles *** ground state is collinear antiferromagnetic with calculated 2.26μB magnetic moment on Fe atoms;and the J_(1)and J_(2) coupling strengths are calculated to be 0.038eV and *** states around EF are dominated by the Fe 3d orbitals which hybridize noticeably to the Se 4p *** the band structure of KFe_(2)Se_(2) is similar to a heavily electron-doped BaFe_(2)As_(2) or FeSe system,the Fermi surface of KFe_(2)Se_(2) is much closer to the FeSe system since the electron sheets around M are symmetric with respect to x-y *** features,as well as the absence of Fermi surface nesting,suggest that the parent KFe_(2)Se_(2) could be regarded as an electron doped FeSe system with possible local moment magnetism.

关键词： system Fermi moment