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Population viability analysis of small population:a case study for Asian elephant in China

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Integrative Zoology 2020年第5期15卷 350-362页

作者： Changhuan HE Jiaojiao DU di zhu Li ZHANG College of Life Sciences Beijing Normal UniversityBeijingChina

Small populations are at risk of extinction from deterministic and stochastic *** than 250 Asian elephants(Elephas maximus)remain in China,and are distributed in a few isolated areas;yet,population viability analyses of this endangered population have not been ***,the current genetic status of the Pu’Er-Mengyang Asian elephant populations in China was analyzed,and the risk of extinction was predicted over the next 500 *** affecting the viability of this population were determined through *** genetic diversity of the population was very low(mean allele number:3.1;expected heterozygosity:0.463),even though a recent population bottleneck was not *** effective population size was approximately 24.1 adult *** adult breeding individuals exist to maintain population *** simulation model showed that this population would not go extinct in the next 500 ***,illegal poaching and harvesting could negatively affect population size.A sensitivity analysis showed that the mean stochastic growth rate of the study population is sensitive to sex ratio,number of breeding females,mortality of females of different age classes,carrying capacity,and lethal *** on our results,we suggest that action should be taken to alleviate inbreeding and any further loss of genetic diversity,by connecting fragmented elephant habitat or by translocating individual *** addition,human–elephant conflict should be mitigated using various modern approaches,including crop guarding techniques,and by encouraging farmers to switch to crops and income sources not vulnerable to elephant raids.

关键词： Asian elephant corridor construction genetic diversity human-elephant conflict population viability analysis

Cobalt-Catalyzed Enantioselective Ring-Opening Reactions of Oxa- and Aza-bicyclic Alkenes with Alkenylboronic Acids

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Chinese Journal of Chemistry 2022年第2期40卷 190-194页

作者： di zhu Yongmei Zhao Qinglei Chong Fanke Meng State Key Laboratory of Heavy Oil Processing College of ScienceChina University of PetroleumBeijing 102249China State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai 200032China

Catalytic enantioselective ring-opening of oxa-and aza-bicyclic alkenes with readily available accessible alkenylboronic acids,promoted by a chiral phosphine-Co complex,is *** a process represents the unprecedented Co-catalyzed introduction of various alkenyl groups onto the oxa-and aza-bicyclic alkenes,affording a wide range of multisubstituted functionalized cyclohexenes in up to 98%yield and 99.5:0.5 er.

关键词： Cobalt Ring-opening Enantioselective catalysis Bicyclic alkene Alkenylboron

Wire electrochemical machining with axial electrolyte flushing for titanium alloy

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Chinese Journal of Aeronautics 2013年第1期26卷 224-229页

作者： Qu Ningsong Fang Xiaolong Li Wei Zeng Yongbin zhu di College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

Titanium and its alloys have found very wide application in aerospace due to their excellent characteristics although their processing is still a challenge. Electrochemical machining is an important issue in the fabrication of titanium and titanium alloys. Wire electrochemical machining （WECM） is mainly used for workpiece cutting under the condition of different thickness plates. It has a great advantage over wire electro-discharge machining, which is the absence of heat-affected zone around the cutting area. Moreover, the wire electrode in WECM could be used repetitively because it is not worn out. Thus, much attention has been paid to WECM. The effective way of removing electrolysis products is of importance to WECM. In this paper, the axial electrolyte flushing is presented to WECM for removing electrolysis products and renewing electrolyte. The Taguchi experiment is conducted to optimize the machining parameters, such as wire feedrate, machining voltage, electrolyte concentration, etc. Experimental results show that WECM with axial electrolyte flushing is a promising issue in the fabrication of titanium alloy （TC1）. The feasibility of multi-wire electrochemical machining is also demonstrated to improve the machining productivity of WECM.

关键词： Axial electrolyte flushing Electro machining Electrochemical machining Titanium alloy Wire electrochemical machining

Comparative study of reduced-order modeling method for the cavitating flow over a hydrofoil

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Journal of Hydrodynamics 2023年第4期35卷 679-699页

作者： Yan-zhao Wu Ran Tao di zhu Ruo-fu Xiao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing100083China College of Engineering China Agricultural UniversityBeijing100083China

As a high-dimensional complex nonlinear dynamic system,the analysis of the essence of flow has always been a difficult problem,especially in the flow including phase *** recent years,it has become a feasible method to reduce the dimension of flow structure by reduced-order modeling(ROM)*** this paper,through the cavitation numerical simulation of NACA0015 hydrofoil,two ROM methods are used to reduce and restore three different cavitation respectively-proper orthogonal decomposition(POD)and dynamic mode decomposition(DMD).The applicability of two methods in cavitation is discussed and reasons are *** results show that for stable cavitation,POD,DMD methods can accurately restore the flow field of a few modes with high *** unstable cavitation,only POD method can restore real flow field *** situation is mainly due to the fact that POD,DMD method are applicable to different energy ratios,and different main mode selection criterion of DMD will lead to different main *** can greatly simplify the complexity of *** a reasonable ROM can improve the accuracy of a small amount of database,and provide a basis for intelligent prediction of flow analysis.

关键词： Hydrofoil cavitation reduced-order model proper orthogonal decomposition dynamic mode decomposition

ESMD-Flow: An Intelligent Flow Forwarding Scheme with Endogenous Security Based on Mimic Defense in Space-Air-Ground Integrated Network

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China Communications 2022年第1期19卷 40-51页

作者： Ziyong Li Yuxiang Hu di zhu JiangxingWu Yunjie Gu PLA Strategic Support Force Information Engineering University Zhengzhou 450002China 61660 Unit of PLA Beijing 100089China

The Space-Air-Ground Integrated Network(SAGIN) realizes the integration of space, air,and ground networks, obtaining the global communication ***-Defined Networking(SDN) architecture in SAGIN has become a promising solution to guarantee the Quality of Service(QoS).However, the current routing algorithms mainly focus on the QoS of the service, rarely considering the security requirement of flow. To realize the secure transmission of flows in SAGIN, we propose an intelligent flow forwarding scheme with endogenous security based on Mimic Defense(ESMD-Flow). In this scheme, SDN controller will evaluate the reliability of nodes and links, isolate malicious nodes based on the reliability evaluation value, and adapt multipath routing strategy to ensure that flows are always forwarded along the most reliable multiple paths. In addition, in order to meet the security requirement of flows, we introduce the programming data plane to design a multiprotocol forwarding strategy for realizing the multiprotocol dynamic forwarding of flows. ESMD-Flow can reduce the network attack surface and improve the secure transmission capability of flows by implementing multipath routing and multi-protocol hybrid forwarding mechanism. The extensive simulations demonstrate that ESMD-Flow can significantly improve the average path reliability for routing and increase the difficulty of network eavesdropping while improving the network throughput and reducing the average packet delay.

关键词： space-air-ground integrated network(SAGIN) endogenous security multipath routing multi-protocol forwarding

Moxa Wool in different Purities and different Growing Years Measured by Terahertz Spectroscopy

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Plant Phenomics 2022年第1期4卷 235-246页

作者： Yongni Shao di zhu Yutian Wang Zhi zhu Wenchao Tang Zhengan Tian Yan Peng Yiming zhu Terahertz Technology Innovation Research Institute Terahertz Spectrum and Imaging Technology Cooperative Innovation CenterShanghai Key Lab of Modern Optical SystemUniversity of Shanghai for Science and TechnologyShanghai 20009China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 200092China School of Acupuncture-Moxibustion and Tuina Shanghai University of Traditional Chinese MedicineChina Shanghai International Travel Healthcare Center Shanghai Customs District P.R.200335China

Moxa wool is a traditional Chinese herbal medicine,which can warm channels to dispel *** present,there is no unified index to evaluate the purity and growing years of moxa wool in the *** is one of the effective substances in the volatile oil of moxa ***,we characterize the purity and growing years of moxa wool by studying *** chromatography-mass spectrometry(GC-MS)and high-performance liquid chromatography(HPLC)are the methods for monitoring terpineol at present,all of which have defects of complicated procedures.

关键词： wool purity unified

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科伦巴博物馆空间建构时间的句法分析

山西建筑 2025年第3期51卷 17-21,95页

作者：朱迪曾克明陈梓欣广州美术学院广东广州510261 澳门城市大学创新设计学院中国澳门999078

基于空间句法理论,运用Depthmap软件对彼得·卒姆托的作品——科伦巴博物馆进行解析,证实了彼得·卒姆托试图运用空间勾勒出建筑的过去、现在和未来,同时也从时间维度去讨论与研究空间。通过句法分析表明,科伦巴博物馆空间的变化所带来... 详细信息

基于空间句法理论,运用Depthmap软件对彼得·卒姆托的作品——科伦巴博物馆进行解析,证实了彼得·卒姆托试图运用空间勾勒出建筑的过去、现在和未来,同时也从时间维度去讨论与研究空间。通过句法分析表明,科伦巴博物馆空间的变化所带来的转折与错位,引导参观者的视线和行动,将建筑遗迹、艺术展品与城市的历史统一起来,用空间建构出了真实的历史。

关键词：科伦巴博物馆空间句法历时性共时性

distributions and accumulation mechanisms of helium in petroliferous basins

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Science China Earth Sciences 2024年第10期67卷 3143-3168页

作者： Pengpeng LI Quanyou LIU Dongya zhu di zhu Zheng ZHOU Xiaoqi WU Qingqiang MENG Jiahao LV Yu GAO Institute of Energy Peking UniversityBeijing 100871China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Petroleum Exploration&Production Research Institute SINOPECBeijing 102206China Energy Research Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China Lancaster Environment Centre Lancaster UniversityLA14YQUK Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Helium is an irreplaceable strategic mineral resource, and commercial helium-rich gas fields(He>0.1%) worldwide are typically discovered serendipitously during hydrocarbon exploration efforts. According to an analysis of 75 helium-rich gas fields and 1048 natural gas samples worldwide, helium in natural gas generally exhibits “scarce”, “accompanying”, and“complex” properties, and helium-rich gas fields often occur at depths 1%). However, geological reserves in the former two types of gas fields are mainly in the range of 10^(7)–10^(11)m^(3), whereas in the latter, they are only in the range of 10^(5)–10^(7)m^(3). There are nevertheless notable disparities in the genesis and migration patterns between helium and gaseous hydrocarbons. Helium necessitates carriers(such as formation water, hydrocarbon fluids, N_(2), mantle-derived fluids, etc.) during both accumulation and long-distance migration processes, where migration conduits are not confined to sedimentary strata, and may extend to the basin's basement, lower crust, and even lithospheric mantle. However, the accumulation conditions of both helium and gaseous hydrocarbons are generally considered equivalent. The presence of gaseous hydrocarbons facilitates both the rapid exsolution of helium within helium-containing fluids and subsequent efficient aggregation in gaseous hydrocarbons, while both reduce helium diffusion and diminish escape flux. In terms of caprock, gypsum, salt, and thick shale as sealing layers contribute to the long-term preservation of helium over geological timescales. Large helium-rich gas fields, predominantly crust-derived gas fields, are primarily concentrated in uplifted zones of ancient cratonic basins and their peripheries. Based on a diagram of the He concentration versus He/N_(2) ratio, crust-derived helium fields can be categorized as basement, combined basement-s

关键词： Helium resource Geochemical characteristics Helium source rock Helium supply pattern Accumulation mechanism Determination of favorable zones

Therapeutic effect of regulating autophagy in spinal cord injury: a network meta-analysis of direct and indirect comparisons

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Neural Regeneration Research 2020年第6期15卷 1120-1132页

作者： Duo Zhang di zhu Fang Wang Ji-Chao zhu Xu Zhai Yuan Yuan Chen-Xi Li Department of Orthopedics Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Orthopedics Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’anShaanxi ProvinceChina Department of Emergency Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’anShaanxi ProvinceChina Department of Spinal Cord Injury Rehabilitation China Rehabilitation Research CenterBeijingChina

Objective:An increasing number of studies indicate that autophagy plays an important role in the pathogenesis of spinal cord injury,and that regulating autophagy can enhance recovery from spinal cord ***,the effect of regulating autophagy and whether autophagy is detrimental or beneficial after spinal cord injury remain ***,in this study we evaluated the effects of autophagy regulation on spinal cord injury in rats by direct and indirect comparison,in an effort to provide a basis for further *** source:Relevant literature published from inception to February 1,2018 were included by searching Wanfang,CNKI,Web of Science,MEDLINE(OvidSP),PubMed and Google Scholar in English and *** keywords included"autophagy","spinal cord injury",and"rat".Data selection:The literature included in vivo experimental studies on autophagy regulation in the treatment of spinal cord injury(including intervention pre-and post-spinal cord injury).Meta-analyses were conducted at different time points to compare the therapeutic effects of promoting or inhibiting autophagy,and subgroup analyses were also *** measure:Basso,Beattie,and Bresnahan ***:Of the 622 studies,33 studies of median quality were included in the ***,Beattie,and Bresnahan scores were higher at 1 day(MD=1.80,95%CI:0.81-2.79,P=0.0004),3 days(MD=0.92,95%CI:0.72-1.13,P<0.00001),1 week(MD=2.39,95%CI:1.85-2.92,P<0.00001),2 weeks(MD=3.26,95%CI:2.40-4.13,P<0.00001),3 weeks(MD=3.13,95%CI:2.51-3.75,P<0.00001)and 4 weeks(MD=3.18,95%CI:2.43-3.92,P<0.00001)after spinal cord injury with upregulation of autophagy compared with the control group(drug solvent control,such as saline group).Basso,Beattie,and Bresnahan scores were higher at 1 day(MD=6.48,95%CI:5.83-7.13,P<0.00001),2 weeks(MD=2.43,95%CI:0.79-4.07,P=0.004),3 weeks(MD=2.96,95%CI:0.09-5.84,P=0.04)and 4 weeks(MD=4.41,95%CI:1.08-7.75,P=0.01)after spinal cord injury with downregulation of autophagy compared w

关键词： autophagy Basso,Beattie,and Bresnahan scores indirect comparison meta-analysis nerve regeneration neural regeneration neurological function rat models regulation spinal cord injury strategy analysis