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Global patterns and ecological d.ivers of taxonomic and phylogenetic endemism in angiosperm genera

Plant diversity 2024年第2期46卷 149-157页

作者： Hong Qian Brent d.Mishler jian Zhang Shenhua Qian Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA University and Jepson Herbaria Department of Integrative BiologyUniversity of CaliforniaBerkeleyCA 94720-2465USA Center for Global Change and Complex Ecosystems Zhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China Shanghai institute of Pollution Control and Ecological Security Shanghai 200092China Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment Ministry of EducationChongqing UniversityChongqing 400045China

Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current ***,we investigated geographic patterns and ecological d.ivers of taxonomic and phylogenetic endemism of angiosperm genera across the *** identify centers of paleo-endemism and neo-endemism of angiosperm genera,and show that they are mostly located.in the Southern Hemisphere in tropical and subtropical regions,particularly in Asia and *** categories of phylogenetic endemism centers can be differentiated using current climate *** climate,historical climate change,and geographic variables together explained~80%of global variation in taxonomic and phylogenetic endemism,while 42-46%,1%,and 15%were independently explained by these three types of variables,*** our findings show that past climate change,current climate,and geography act together in shaping endemism,which are consistent with the findings of previous studies that higher temperature and topographic heterogeneity promote *** study showed that many centers of phylogenetic endemism of angiosperms,including regions in Amazonia,Venezuela,and west-central tropical Africa that have not previously been identified as biodiversity hotspots,are missed by taxon-based measures of endemism,indicating the importance of including evolutionary history in biodiversity assessment.

关键词： Angiosperm Current climate Endemism Historical climate change Topographic heterogeneity

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Prescribed-Time Nash Equilibrium Seeking for Pursuit-Evasion Game

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iEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1518-1520页

作者： Lei Xue jianfeng Ye Yongbao Wu jian Liu d.C.Wunsch Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationNanjing 210096 School of Automation Southeast UniversityNanjing 210096China department of Electrical and Computer Engineering Missouri University of Science and TechnologyRollaMO 65409 USA iEEE

dear Editor,This letter is concerned with prescribed-time Nash equilibrium(PTNE)seeking problem in a pursuit-evasion game(PEG)involving agents with second-order *** order to achieve the prior-given and user-defined convergence time for the PEG,a PTNE seeking algorithm has been developed to facilitate collaboration among multiple pursuers for capturing the evader without the need for any global ***,it is theoretically proved that the prescribed.ime convergence of the designed algorithm for achieving Nash equilibrium of ***,the effectiveness of the PTNE method was validated by numerical simulation results.A PEG consists of two groups of agents:evaders and *** pursuers aim to capture the evaders through cooperative efforts,while the evaders strive to evade *** is a classic noncooperative *** has attracted plenty of attention due to its wide application scenarios,such as smart grids[1],formation control[2],[3],and spacecraft rendezvous[4].it is noteworthy that most previous research on seeking the Nash equilibrium of the game,where no agent has an incentive to change its actions,has focused on asymptotic and exponential convergence[5]-[7].

关键词： seeking prescribed convergence

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A Novel 3d Gait Model for Subject identification Robust against Carrying and dressing Variations

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Computers, Materials & Continua 2024年第7期80卷 235-261页

作者： jian Luo Bo Xu Tardi Tjahjadi jian Yi College of information Science and Engineering Hunan Normal UniversityChangsha410000China School of Engineering University of WarwickCoventryCV47ALUK

Subject identification via the subject’s gait is challenging due to variations in the subject’s carrying and dressing conditions in real-life *** paper proposes a novel targeted 3-dimensional(3d)gait model(3dGait)represented by a set of interpretable 3dGait descriptors based on a 3d parametric body *** 3dGait descriptors are utilised as invariant gait features in the 3dGait recognition method to address object carrying and *** 3dGait recognitionmethod.involves 2-dimensional(2d)to 3dGaitdata learningbasedon3d.irtual samples,a semantic gait parameter estimation Long Short Time Memory(LSTM)network(3d-SGPE-LSTM),a feature fusion deep model based on a multi-set canonical correlation analysis,and SoftMax recognition ***,a sensory experiment based on 3d body shape and pose deformation with 3d virtual dressing is used to fit 3dGait onto the given 2d gait images.3dinterpretable semantic parameters control the 3d morphing and dressing *** degree measurement determines the semantic descriptors of 2d gait images of subjects with various shapes,poses and ***,using the 2d gait images as input and the subjects’corresponding 3d semantic descriptors as output,an end-to-end 3d-SGPE-LSTM is constructed and ***,body shape,pose and external gait factors(3d-eFactors)are estimated using the 3d-SGPE-LSTM model to create a set of interpretable gait descriptors to represent the 3dGait Model,i.e.,3d.intrinsic semantic shape descriptor(3dShape);3d skeleton-based gait pose descriptor(3d-Pose)and 3d dressing with other ***,the 3d-Shape and 3d-Pose descriptors are coupled to a unified pattern space by learning prior knowledge from the *** research on CASiA B,CMU MoBo,TUM GAid and GPJATK databases shows that 3dGait is robust against object carrying and dressing variations,especially under multi-cross variations.

关键词： Gait recognition human identification three-dimensional gait canonical correlation analysis

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The Essential 2-rank for Classical Groups

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2169-2186页

作者： jian Bei AN Yong XU department of Mathematics University of AucklandAucklandNew Zealand School of Mathematics and Statistics He’nan University of Science and TechnologyLuoyang 471023P.R.China

Let G be a symplectic or orthogonal group defined over a finite field with odd characteristic and let d≤G be a Sylow *** this paper,we classify the essential 2-subgroups and determine the essential 2-rank of the Frobenius category Fd(G).Together with the results of An–dietrich and Cao–An–Zeng,this completes the work of essential subgroups and essential ranks of classical groups.

关键词： Frobenius category conjugation families essential 2-rank symplectic groups orthogonal groups

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Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or d for short),^(3)He,^(4)He,and^(7) Li produced.in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(d/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRiMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated d/H ***,the calculated d/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved.in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

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Facile synthesis of intra-nanogap enhanced Raman tags with different shapes

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Nano Research 2024年第9期17卷 8415-8423页

作者： Sanjun Fan Brian T.Scarpitti Zhewen Luo Abigail E.Smith jian Ye Zachary d.Schultz department of Chemistry and Biochemistry The Ohio State UniversityColumbusOhio 43210USA School of Biomedical Engineering Shanghai Jiao Tong UniversityShanghai 200030China

Hot spot engineering in plasmonic nanostructures plays a significant role in surface-enhanced Raman scattering(SERS)for bioanalysis and cell ***,creating stable,reproducible,and strong SERS signals remains challenging due to the potential interference from surrounding chemicals and locating SERS-active analytes into hot-spot ***,we developed a straightforward approach to synthesize intra-gap nanoparticles encapsulating 4-nitrobenzenethiol(4-NBT)as a reporter molecule within these gaps to avoid outside *** made three kinds of intra-gap nanoparticles using nanorods,bipyramids,and nanospheres as cores,in which the nanorods based.intra-gap nanoparticles exhibit the highest SERS *** advantage of our method.is the ease of preparation of high-yield and stable intra-gap nanoparticles characterized by a short incubation time(10 min)with 4-NBT and quick synthesis without requiring an ad.itional step to centrifuge for the purification of core *** intense localized field.in the synthesized hot spots of these plasmonic gap nanostructures holds great promise as a SERS substrate for a broad range of quantitative optical applications.

关键词： hot spot engineering surface enhanced Raman scattering intra-gap nanoparticles 4-nitrobenzenethiol

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A product version of the Hilton-Milner-Frankl theorem

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Science China Mathematics 2024年第2期67卷 455-474页

作者： Peter Frankl jian Wang Alfréd Rényi institute of Mathematics Hungarian Academy of SciencesBudapest H-1053Hungary department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

Two families F and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|F ∩ G|≥t for all F ∈ F, G ∈ G and | ∩ {F : F ∈ F}| < t, | ∩ {G : G ∈ G}| < t. in the present paper,we determine... 详细信息

Two families F and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|F ∩ G|≥t for all F ∈ F, G ∈ G and | ∩ {F : F ∈ F}| in the present paper,we determine the maximum product of the sizes of two non-trivial cross t-intersecting families of k-subsets of{1, 2,..., n} for n≥4(t + 2)2k2, k≥5, which is a product version of the Hilton-Milner-Frankl theorem.

关键词： extremal set theory cross t-intersecting family product version non-trivial

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design,fabrication,and characterization of hierarchical mechanical metamaterials

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Frontiers of Mechanical Engineering 2024年第1期19卷 73-83页

作者： jian SONG Junfei YAN Bengang Yi Automotive Engineering Research institute BYD Auto Industry Co.Ltd.Shenzhen 518000China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China

Natural mechanical materials,such as bamboo and bone,often exhibit superior specific mechanical properties due to their hierarchical porous *** the principle of hierarchy as inspiration can facilitate the development of hierarchical mechanical metamaterials(HMMs)across multiple length scales via 3d *** this work,we propose self-similar HMMs that combine octet-truss(OCT)architecture as the first and second orders,with cubic architecture as the third or more *** HMMs were fabricated using stereolithography 3d printing,with the length sizes ranging from approximately 200µm to the centimeter *** compressive stress–strain behaviors of HMMs exhibit a zigzag characteristic,and the toughness and energy absorption can be significantly enhanced by the hierarchical *** compressive moduli are comparable to that of natural materials,and the strengths are superior to that of most polymer/metal foams,alumina hollow/carbon lattices,and other natural ***,the flexural stress–strain curves exhibit a nonlinear behavior,which can be attributed to the hierarchical architecture and local damage *** relatively high mechanical properties can be attributed to the synergistic effect of the stretch-dominated OCT architecture and the bending-dominated cube ***,an ultralight HMM-integrated unmanned aerial vehicle(HMM-UAV)was successfully designed and *** HMM-UAV is~85%lighter than its bulk counterpart,remarkably extending the flight duration time(~53%).This work not only provides an effective design strategy for HMMs but also further expands the application benchmark of HMMs.

关键词： 3d printing mechanical metamaterials hierarchical architecture mechanical behavior unmanned aerial vehicle(UAV)

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influence of pore structure heterogeneity on channeling channels during hot water flooding in heavy oil reservoir based on CT scanning

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Petroleum Science 2024年第4期21卷 2407-2419页

作者： Qing-Jun du Hao-Yu Zheng jian Hou Yong-Ge Liu jian-Fang Sun dong Zhao State Key Laboratory of deep Oil and Gas China University of Petroleum (East China) School of Petroleum Engineering China University of Petroleum (East China) Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Petroleum Exploration and Production Research institute

Hot water flooding is an effective way to develop heavy oil reservoirs. However, local channeling channels may form, possibly leading to a low thermal utilization efficiency and high water cut in the reservoir. The pore structure heterogeneity is an important factor in forming these channels. This study proposes a method that mixes quartz sand with different particle sizes to prepare weakly heterogeneous and strongly heterogeneous models through which hot water flooding experiments are *** the experiments, computer tomography(CT) scanning identifies the pore structure and micro remaining oil saturation distribution to analyze the influence of the pore structure heterogeneity on the channeling channels. The oil saturation reduction and average pore size are divided.into three levels to quantitatively describe the relationship between the channeling channel distribution and pore structure heterogeneity. The zone where oil saturation reduction exceeds 20% is defined as a channeling *** scanning area is divided.into 180 equally sized zones based on the CT scanning images, and threedimensional(3d) distributions of the channeling channels are developed. Four micro remaining oil distribution patterns are proposed, and the morphology characteristics of micro remaining oil inside and outside the channeling channels are analyzed. The results show that hot water flooding is more balanced.in the weakly heterogeneous model, and the oil saturation decreases by more than 20% in most zones without narrow channeling channels forming. in the strongly heterogeneous model, hot water flooding is unbalanced, and three narrow channeling channels of different lengths form. in the weakly heterogeneous model, the oil saturation reduction is greater in zones with larger pores. The distribution range of the average pore size is larger in the strongly heterogeneous model. The network remaining oil inside the channeling channels is less than outside the channeling channels,

关键词： Heavy oil Hot water flooding Pore structure Channeling channels CT scanning

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Liquid-phase epitaxial layer by layer brushing fabrication of metalorganic frameworks films

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Nano Research 2024年第6期17卷 5698-5704页

作者： Li-Mei Chang Rui Zhai Zhi-Zhou Ma jian-dong Huang Zhi-Gang Gu jian Zhang College of Chemistry Fuzhou UniversityFuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

development of metal-organic framework(MOF)films is of great importance to expand their ***,we report a facile and universal method of liquid-phase epitaxial(LPE)layer by layer(LBL)brushing approach for fabricating MOF films on various substrates in a high-throughput *** MOF films preparation method offers a great prospective to cost-effectively construct films with short preparation time and little reagent ***,this LBL brushing approach has been implemented successfully to assemble various MOF films,including HKUST-1,zeolitic imidazolate framework-8(ZiF-8),Cu(bdc),and Cu_(2)(L)_(2)P(L=bdc,ndc,and cam;P=dabco and bipy).Afterwards,the classic MOF HKUST-1 and ZiF-8 films were grown on sensor chip electrode and porous fiber support for good volatile organic compounds(VOCs)selective sensing and water purification *** study demonstrates that this LBL brushing preparation method can be employed to synthesize various MOF films with a variety of characteristics to realize their sensing and separation applications.

关键词： metal-organic framework porous materials layer by layer fabrication film

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