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The competition between Bidens pilosa and Setaria viridis alters soil microbial composition and soil ecological function

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Journal of Integrative Agriculture 2024年第1期23卷 267-282页

作者： qiao Li Jianying Guo han Zhang Mengxin Zhao State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China College of Life Science Yangtze UniversityJingzhou 434025China

Bidens pilosa is recognized as one of the major invasive plants in *** invasion has been associated with significant losses in agriculture,forestry,husbandry,and *** ecosystems play an important role in alien plant *** within the soil act as intermediaries between plants and soil ecological functions,playing a role in regulating soil enzyme activities and nutrient *** the interactions between invasive plants,soil microorganisms,and soil ecological processes is vital for managing and mitigating the impacts of invasive species on the *** this study,we conducted a systematic analysis focusing on *** and Setaria viridis,a common native companion plant in the invaded *** simulate the invasion process of ***,we constructed homogeneous plots consisting of *** and *** grown separately as monocultures,as well as in *** rhizosphere and bulk soils were collected from the alien plant *** and the native plant *** order to focus on the soil ecological functional mechanisms that contribute to the successful invasion of ***,we analyzed the effects of *** on the composition of soil microbial communities and soil ecological *** results showed that the biomass of *** increased by 27.51% and that of *** was significantly reduced by 66.56%.The organic matter contents in the bulk and rhizosphere soils of *** were approximately 1.30 times those in the native plant *** TN and NO_(3)^(-)contents in the rhizosphere soil of *** were 1.30 to 2.71 times those in the native plant *** activities of acid phosphatase,alkaline phosphatase,and urease in the rhizosphere soil of *** were 1.98-2.25 times higher than in the native plant *** high-throughput sequencing of the16S rRNA gene,we found that *** altered the composition of the soil microbial ***,many genera in Actinobacteria and Proteobacteri

关键词： plant invasion Bidens pilosa soil microbial composition soil properties soil enzyme activities

Quasi-static and dynamic plastic deformation behavior in titanium with vanadium addition

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Rare Metals 2023年第7期42卷 2361-2370页

作者： qiao-Chu Wang song-Xiao Hui Wen-Jun Ye Rui Liu Xiao-Yun song State Key Laboratory for Fabrication&Processing of Nonferrous Metals General Research Institute for Nonferrous MetalsBeijing100088China

Compressive properties,microstructure features and deformation modes were investigated in binary Ti-(2,4,8)wt%V alloys during quasi-static(1×10^(-3)s^(-1))and dynamic(3×10^(3)s^(-1))*** compressive behavior shows a strong dependence on the loading strain rate and vanadium content contained in pure Ti,such that the flow stress increases with the increase in strain rate and vanadium content ranging from 2 wt%to 8 wt%.The microstructure features are clearly different from each other for alloys with different vanadium contents or under quasi-static and dynamic loading *** examination of deformation microstructures by optical microscopy and electron backscattered diffraction indicates that twinning behavior occurs during quasi-static and dynamic compressions and the twinning density increases with strain rate increasing but decreases with vanadium *** existence of{1012},{1121}and{1122}type twinning was further *** the help of the calculated Schmid factor map,the values of critical resolved shear stress of twinning types mentioned above have been obtained and verified to be rarely affected by the loading strain rate but sensitive to the vanadium *** vanadium-rich alloys(Ti-8V),twins are rarely observed but dislocation slip mechanism is active by transmission electron microscopy *** vanadium content increasing,both the critical resolved shear stress of twinning types and the content ofβphase with abundant slip systems increase,reflecting a suppression of twinning but an active dislocation slip mechanism.

关键词： Titanium alloys Strain rate Deformation mode Twinning Electron backscattered diffraction

Influence of Human Papillomavirus E7 Oncoprotein on Maturation and Function of Plasmacytoid Dendritic Cells In Vitro

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Virologica Sinica 2018年第6期33卷 493-501页

作者： Rui han Yin-Jing song Si-Yuan Sun Qiang Zhou Xian-Zhen Chen qiao-Li Zheng Hao Cheng Department of Dermatology and Venereology Sir Run Run Shaw Hospital School of Medicine Zhejiang University

The major difficulties of human papillomavirus(HPV) treatment are its persistence and recurrence. The HPV E7 oncoprotein-loaded dendritic cells have been evaluated as cellular vaccine in previous reports. Plasmacytoid dendritic cells(pDCs) play an essential role of connecting the innate immune response and adaptive immune response in the immune system. But they function in HPV E7 loading is unclear. To investigate whether loading of the HPV type 6b, 11, and 16 E7 proteins affects the activity of pDCs, human peripheral blood-separated pDCs and mouse bone marrow-derived pDCs were pulsed with the HPV E7 proteins. The expression levels of CD40, CD80, CD86, and MHC II were significantly upregulated in pDCs upon HPV 6b/11 E7 protein pulse. The secretion and gene expression of type I IFN and IL-6 were both upregulated by HPV 6b/11 E7 proteins, more significant than HPV 16 E7 protein. The expression of essential factors of TLR signaling pathway and JNK/p38 MAP kinase signaling pathway were all increased in HPV 6b/11 E7 proteins pulsed pDCs. Our results suggest that HPV E7 proteins could promote the differentiation and maturation of pDCs and activate the TLR and MAPK pathway to induce host innate immune response. It might be conducive to explore novel immunotherapy targeting HPV infection with HPV E7 loaded pDC.

关键词： Human papillomavirus(HPV) Plasmacytoid dendritic cells(pDCs) Toll-like receptors(TLRs) Innate immunity

A Preconditioned Multigrid Method for Efficient Simulation of Three-dimensional Compressible and Incompressible Flows

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Chinese Journal of Aeronautics 2007年第4期20卷 289-296页

作者： han Zhonghua He Fei song Wenping qiao Zhide National Key Laboratory of Aerodynamic Design and Research School of Aeronautics Northwestern Polytechnical University Xi ＇an 710072 China

To develop an efficient and robust aerodynamic analysis method for numerical optimization designs of wing and complex configuration, a combination of matrix preconditioning and multigrid method is presented and investigated. The time derivatives of three-dimensional Navier-Stokes equations are preconditioned by Choi-Merkle preconditioning matrix that is originally designed for two-dimensional low Mach number viscous flows. An extension to three-dimensional viscous flow is implemented, and a method improving the convergence for transonic flow is proposed. The space discretizaition is performed by employing a finite-volume cell-centered scheme and using a central difference. The time marching is based on an explicit Rtmge-Kutta scheme proposed by Jameson. An efficient FAS multigrid method is used to accelerate the convergence to steady-state solutions. Viscous flows over ONERA M6 wing and M100 wing are numerically simulated with Mach numbers ranging from 0.010 to 0.839. The inviscid flow over the DLR-F4 wing-body configuration is also calculated to preliminarily examine the performance of the presented method for complex configuration. The computed results are compared with the experimental data and good agreement is achieved. It is shown that the presented method is efficient and robust for both compressible and incompressible flows and is very attractive for aerodynamic optimization designs of wing and complex configuration.

关键词： Navier-Stokes equations preconditioning method multigrid method numerical simulation

Mobile phone recognition method based on bilinear convolutional neural network

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Science China(Technological Sciences) 2021年第11期64卷 2477-2484页

作者： han HongGui ZHEN Qi YANG HongYan DU YongPing qiao JunFei Faculty of Information Technology Beijing University of TechnologyBeijing 100124China

Model recognition of second-hand mobile phones has been considered as an essential process to improve the efficiency of phone recycling. However, due to the diversity of mobile phone appearances, it is difficult to realize accurate recognition. To solve this problem, a mobile phone recognition method based on bilinear-convolutional neural network(B-CNN) is proposed in this ***, a feature extraction model, based on B-CNN, is designed to adaptively extract local features from the images of secondhand mobile phones. Second, a joint loss function, constructed by center distance and softmax, is developed to reduce the interclass feature distance during the training process. Third, a parameter downscaling method, derived from the kernel discriminant analysis algorithm, is introduced to eliminate redundant features in B-CNN. Finally, the experimental results demonstrate that the B-CNN method can achieve higher accuracy than some existing methods.

关键词： bilinear convolutional neural network low-rank decomposition joint loss fine-grained image recognition

α-In_(2)Se_(3)/PtX_(2)(X=S,Se,Te)异质结电子结构调控研究

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大连理工大学学报 2025年第1期65卷 1-9页

作者：韩善成李京杰王楠黄火林郝松大连理工大学光电工程与仪器科学学院辽宁大连116024 大连理工大学集成电路学院辽宁大连116024

二维范德华异质结因其无悬挂键界面和无应力失配等特性,在后摩尔时代的高性能电子学领域具备广泛的应用潜力.然而,当前二维范德华异质结的原子结构固定,限制了对其物性的动态调控.因此提出了利用二维铁电材料α-In_(2)Se_(3)与PtX_(2)(X... 详细信息

二维范德华异质结因其无悬挂键界面和无应力失配等特性,在后摩尔时代的高性能电子学领域具备广泛的应用潜力.然而,当前二维范德华异质结的原子结构固定,限制了对其物性的动态调控.因此提出了利用二维铁电材料α-In_(2)Se_(3)与PtX_(2)(X=S,Se,Te)构建范德华异质结,并通过电场调控α-In_(2)Se_(3)的结构,从而实现对α-In_(2)Se_(3)/PtX_(2)原子结构和电子结构的动态调控.基于第一性原理计算,异质结带隙取决于α-In_(2)Se_(3)的极化方向,α-In_(2)Se_(3)/PtS2、α-In_(2)Se_(3)/PtSe_(2)、α-In_(2)Se_(3)/PtTe_(2)带隙分别为1.25/1.66 eV、0.74/1.34 eV、0.34/0.77 eV.此外,α-In_(2)Se_(3)的极化翻转可调控异质结的能带排列类型,α-In_(2)Se_(3)/PtS2能带排列从Ⅰ型变为Ⅱ型;α-In_(2)Se_(3)/PtSe_(2)能带排列虽保持Ⅱ型,但能带相对位置发生变化;α-In_(2)Se_(3)/PtTe_(2)能带排列从Ⅱ型变为Ⅰ型.通过二维铁电材料的极化翻转来调控二维范德华异质结电子性质的技术路径,为未来智能电子器件的实现提供了潜在的技术方案.

关键词：铁电性二维材料范德华异质结电子结构

Task assignment for social-oriented crowdsourcing

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Frontiers of Computer Science 2021年第2期15卷 39-49页

作者： Gang WU Zhiyong CHEN Jia LIU Donghong han Baiyou qiao School of Computer Science and Engineering Northeastern UniversityShenyang110004China State Key Laboratory for Novel Software Technology Nanjing UniversityNanjing210023China

Crowdsourcing has become an efficient measure to solve machine-hard problems by embracing group wisdom,in which tasks are disseminated and assigned to a group of workers in the way of open *** social relationships formed during this process may in turn contribute to the completion of future *** this sense,it is necessary to take social factors into consideration in the research of ***,there is little work on the interactions between social relationships and crowdsourcing *** this paper,we propose to study such interactions in those social-oriented crowdsourcing systems from the perspective of task assignment.A prototype system is built to help users publish,assign,accept,and accomplish location-based crowdsourcing tasks as well as promoting the development and utilization of social relationships during the ***,in order to exploit the potential relationships between crowdsourcing workers and tasks,we propose a“worker-task”accuracy estimation algorithm based on a graph model that joints the factorized matrixes of both the user social networks and the history“worker-task”*** the worker-task accuracy estimation matrix,a group of optimal worker candidates is efficiently chosen for a task,and a greedy task assignment algorithm is proposed to further the matching of worker-task pairs among multiple crowdsourcing tasks so as to maximize the overall *** with the similarity based task assignment algorithm,experimental results show that the average recommendation success rate increased by 3.67%;the average task completion rate increased by 6.17%;the number of new friends added per week increased from 7.4 to 10.5;and the average task acceptance time decreased by 8.5 seconds.

关键词： crowdsourcing social networks task assignment

Enhanced Efficiency of Dye-sensitized Solar Cells Using rGO@TiO2 Nanotube Hybrids

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Chemical Research in Chinese Universities 2018年第2期34卷 269-273页

作者： LIU Rui qiao Yingjie song Yingjin song Kehan LIU Chuan School of Science Harbin University of Commerce Harbin 150076 P. R. China College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 P R. China Department of Chemistry Harbin University Harbin 150050 P. R. China Department of Chemistry Qiqihar University Qiqihar 161006 P. R. China

We established a novel strategy for the synthesis of reduced graphene oxide（rGO）@TiO2 nanotube hybrids using an 18 W UV-assisted photo-catalytic reduction method for utilization as photo-anode of dye-sensitized solar cells（DSSCs）. The photo-conversion efficiency of DSSCs was significantly enhanced after the addition of rGO, and in addition, the photo-anode showed decreased internal resistance. Analysis of rGO@TiO2 hybrids by transmissions scanning electron microscopy（TEM）, X-ray diffraction（XRD）, Raman spectra, N2 adsorption and desorption, atomic force microscopy（AFM） and X-ray photoelectron speetroscopy（XPS） demonstrates that the rGO modified TiO2 nanotubes can increase the short-circuit current and the conversion efficiency of dye-sensitized solar cells. The efficiency is improved by almost two folds as much compared to those of the bare TiO2 nanotubes.

关键词： TiO2 nanotube array, Reduced graphene oxide(rGO) Hybrid Dye-sensitized solar eell(DSSC)

Ringing cancellation in Carr-Purcell-Meiboom-Gill-type sequences

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Magnetic Resonance Letters 2022年第4期2卷 233-242页

作者： Shin Utsuzawa Marcus Donaldson Yi-qiao song Schlumberger-Doll Research CambridgeMA02139USA John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA02138USA Athinoula A.Martinos Center for Biomedical Imaging Department of RadiologyMassachusetts General HospitalCharlestownMA02129USA

We propose a four-step phase cycling scheme that can cancel ringings from both the excitation and the refocusing pulses in Carr-Purcell-Meiboom-Gill(CPMG)*** allows accurate measurements of the first echo with short echo spacing tE,yielding improved precision of porosity,permeability,and fluid type identification in porous media study,at a cost of~25%signal *** our example,we achieved tE=100 ms on a 6.8 MHz unilateral NMR sensor without using a *** methods can be integrated in all nuclear magnetic resonance(NMR)protocols using CPMG,such as relaxation(T1,T2)and diffusion measurements,and do not require additional hardware(e.g.,Qswitches)to cancel ringing(although it can be used with a Q-switch to further reduce residual ringing).

关键词： CPMG Ringing cancellation Phase cycling