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A reference-grade genome of the xerophyte Ammopiptanthus mongolicus sheds light on its evolution history in legumes and droughttolerance mechanisms

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Plant Communications 2024年第7期5卷 157-177页

作者： Lei Feng Fei Teng Na Li jia-cheng zhang Bian-jiang zhang Sau-Na Tsai Xiu-Le Yue Li-Fei Gu Guang-Hua Meng Tian-Quan Deng Suk-Wah Tong Chun-Ming Wang Yan Li Wei Shi Yong-Lun Zeng Yue-Ming jiang Weichang Yu Sai-Ming Ngai Li-Zhe An Hon-Ming Lam Jun-Xian He School of Life Sciences and State Key Laboratory of Agrobiotechnology The Chinese University of Hong KongSha TinNew TerritoriesHong KongChina Guangdong Provincial Key Laboratory of Biotechnology for Plant Development School of Life SciencesSouth China Normal UniversityGuangzhou 510631China BGI-Shenzhen Tech Co. Ltd.Beishan Industrial ZoneYantian DistrictShenzhen 518083China School of Life Sciences and Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations Lanzhou UniversityLanzhou 730030China State Key Laboratory of Subtropical Silviculture Zhejiang Agriculture and Forestry UniversityHangzhou 311300China State Key Laboratory of Plant Diversity and Specialty Crops South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China Guangdong Provincial Key Laboratory of Applied Botany&Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China College of Life Sciences and Oceanography Shenzhen UniversityShenzhen 518060China State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing 100083China

Plants that grow in extreme environments represent unique sources of stress-resistance genes and *** mongolicus(Leguminosae)is a xerophytic evergreen broadleaf shrub native to semi-arid and desert regions;however,its drought-tolerance mechanisms remain poorly ***,we report the assembly of a reference-grade genome for ***,describe its evolutionary history within the legume family,and examine its drought-tolerance *** assembled genome is 843.07 Mb in length,with 98.7%of the sequences successfully anchored to the nine chromosomes of *** genome is predicted to contain 47611 protein-coding genes,and 70.71%of the genome is composed of repetitive sequences;these are dominated by transposable elements,particularly longterminal-repeat *** analyses revealed two whole-genome duplication(WGD)events at 130 and 58 million years ago(mya)that are shared by the genus Ammopiptanthus and other legumes,but no species-specific WGDs were found within this *** genome reconstruction revealed that the *** genome has undergone fewer rearrangements than other genomes in the legume family,confirming its status as a"relict plant".Transcriptomic analyses demonstrated that genes involved in cuticular wax biosynthesis and transport are highly expressed,both under normal conditions and in response to polyethylene glycol-induced *** induction of genes related to ethylene biosynthesis and signaling was also observed in leaves under dehydration stress,suggesting that enhanced ethylene response and formation of thick waxy cuticles are two major mechanisms of drought tolerance in *** expression of AmERF2,an ethylene response factor unique to ***,can markedly increase the drought tolerance of transgenic Arabidopsis thaliana plants,demonstrating the potential for application of *** genes in crop improvement.

关键词： Ammopiptanthus mongolicus genome sequencing genome evolution drought tolerance cuticular wax ethylene

Microstructure and properties evolution of Nb-bearing medium Cr wear-resistant cast steel during heat treatment

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Journal of Iron and Steel Research International 2021年第6期28卷 739-751页

作者： jia-cheng zhang Tuo zhang Yi-tao Yang School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

The effect of quenching temperature and cooling conditions on the microstructure and mechanical properties of a 0.2%Nb medium chromium wear-resistant cast steel was *** microstructure,carbides and volume fraction of retained austenite were characterized using the optical microscope,scanning electron microscope,transmission electron microscope and X-ray *** influence of heat treatment on hardness,impact toughness and tensile properties of test steel was *** can be observed that lath martensite can be obtained under the condition of air cooling and oil cooling upon austenitizing in the range of 900–1020℃.Total carbide content of 0.2–1.1 wt.%under air cooling is more than that under oil cooling due to the lower cooling ***6C5,M23C6 and M7C3 were found at lower austenitizing temperature,of which niobium carbide mostly located at grain boundaries,while chromium carbides were uniformly distributed in the matrix with the size of 20–50 *** chromium carbides are basically dissolved into the matrix in test steel austenitized at 1020°***,the negligible growth of prior austenite grain size is *** austenitized at 1020℃ and cooled in air+tempered at 200℃ has a best combination of hardness,plasticity and tensile strength due to fine grain size and more amount of retained *** this condition,the hardness is 58 HRC,the impact toughness is 22.92 J/cm^(2),and the tensile strength is 1136.9 MPa.

关键词： Wear-resistant steel Quenching temperature Cooling condition Carbide Retained austenite Strengthening Toughening

Friction and wear behavior and mechanism of low carbon microalloyed steel containing Nb

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China Foundry 2023年第3期20卷 263-270页

作者： Mei-yi Yuan jia-cheng zhang Yi-tao Yang School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

Dry sliding friction and wear test of Nb containing low carbon microalloyed steel was carried out at room temperature,and the effect of Nb on the wear behavior of the steel,as welll as the mechanism was *** electron microscopy(SEM) and energy dispersive spectrometry(EDS) were employed to analyze the morphology and composition of the worn surface,and the structure evolution of the plastic deformation *** carbide content and type in the steel were analyzed by the electrolytic extraction device and X-ray diffraction(XRD).The experimental results demonstrate that the addition of 0.2% Nb can refine the grain and generate Nb C to improve the wear resistance of the *** enhancing the load and speed of wear experiment,the wear mechanism of the test steel with 0.2% Nb changes from slight oxidation wear to severe adhesion wear and oxidation *** with the load,the increase in the rotation speed exerts a greater influence on the wear of the test steel.

关键词： Nb content low carbon microalloyed steel friction and wear carbide

Detection of ryanodine receptor target-site mutations in diamide insecticide-resistant Spodoptera frugiperda in China

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Insect Science 2021年第3期28卷 639-648页

作者： Sheng-Lan Lv Yang Shi jia-cheng zhang Pei Liang Lei zhang Xi-Wu Gao College of Plant Protection China Agricultural UniversityBeijingChina

Spodoptera frugiperda(Lepidoptera:Noctuidae)is a widely distributed pest of *** it invaded China in 2018,it has caused serious damage to local corn ***,an anthranilic diamide insecticide,has been widely used to control lepidopteran *** is a new allosteric modulator insecticide devel-oped based on chlorantraniliprole,so it has a similar mechanism and insecticidal *** this study,we investigated resistance levels to chlorantraniliprole and tetrachloropyramid in *** from 13 populations in *** the populations tested,the relative highest resistance to chlorantraniliprole occurred in the Guangzhou population,and the most susceptible to chlorantraniliprole was found in the Wuhan *** lethal dosage LD50 value of the Guangzhou population against chlorantraniliprole was 27.8-fold higher than that of the Wuhan *** differences were observed among 5".frugiperda populations in terms of sensitivity to *** mutations at the 14734 site of the ryanodine receptor(RyR)were found,while no mutations were found in the G4891 *** mutations were detected in only two of the 786 individuals analyzed one from the Qinzhou population and other from the Anshun population(frequency below 2%in both cases).There were no significant differences in the expression levels of RyR between Guangzhou and Wuhan *** summary,our results indicate that:(i)*** has low resistance levels to diamide insecticides in China;and(ii)the differences in relative resistance among the 13 populations analyzed are not caused by the mutations in RyR or the expression of RyR.

关键词： diamide insecticides resistance resistance risk Spodoptera frugiperda

Neural Parse Combination

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Journal of Computer Science & Technology 2017年第4期32卷 749-757页

作者： Lin-Er Yang Mao-Song Sun Yong cheng jia-cheng zhang Zheng-Hao Liu Huan-Bo Luan Yang Liu Department of Computer Science and Technology Tsinghua University Beijing 100084 China State Key Laboratory of Intelligent Technology and Systems Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China jiangsu Collaborative Innovation Center for Language Ability Jiangsu Normal University Xuzhou 221009 China Institute for Interdisciplinary Information Sciences Tsinghua University Beijing 100084 China

Analyzing the syntactic structure of natural languages by parsing is an important task in artificial intelligence. Due to the complexity of natural languages, individual parsers tend to make different yet complementary errors. We propose a neural network based approach to combine parses from different parsers to yield a more accurate parse than individual ones. Unlike conventional approaches, our method directly transforms linearized candidate parses into the ground-truth parse. Experiments on the Penn English Treebank show that the proposed method improves over a state-of-the-art parser combination approach significantly.

关键词： neural network parsing parse combination

The configuration of Au^(δ+)-ZrO_(2)^(δ−)species induced activation enhances electrocatalytic CO_(2)to formate conversion

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Nano Research 2024年第7期17卷 6006-6015页

作者： Yongjian jia Yadi zhang Mengque Lin Yangyang cheng Yanjie Xu National Engineering Research Center for Technology and Equipment of Environmental Deposition Lanzhou Jiaotong UniversityLanzhou 730070China Key Lab of Opt-Electronic Technology and Intelligent Control of Ministry of Education Lanzhou Jiaotong UniversityLanzhou 730070China School of Environmental Engineering and Chemistry Luoyang Institute of Science and TechnologyLuoyang 471023China

Electrochemical CO_(2)conversion into value-added chemicals is a promising technology to solve the greenhouse effect and recycle chemical ***,the electrochemical CO_(2)reduction reaction(e-CO_(2)RR)is seriously compromised by weak CO_(2)adsorption and a rough CO_(2)activation process based on the chemical inertness of the CO_(2)molecule and the formed fragile metal–C/O *** this paper,we designed and fabricated Au particles embedded in ZrO_(2).The configuration of Au particles being of positive charge and ZrO_(2)with negative charge is induced and generated by metal–support interactions(MSIs).As a result,Au/ZrO_(2)@C presents a big difference in the CO_(2)conversion compared with the known work,affording a formate yield of 112.5μmol·cm^(−2)·h^(−1)at−1.1 V *** hydrogen electrode(RHE),and a max formate Faradaic efficiency of up to 94.1%at−0.9 V *** superior performance was attributed to the activated Au–ZrO_(2)interface to form the Au^(δ+)*** insitu Fourier transform infrared(FTIR)spectroscopy and theoretical calculations show that the MSIs configuration can be inclined to the*OCO intermediate generation on Au^(δ+)species activating CO_(2)molecules and then accelerate the formation of the*OCHO intermediate in e-CO_(2)RR,thereby favoring the CO_(2)conversion to formate.

关键词： electrochemical CO_(2)reduction reaction(e-CO_(2)RR) Au_(δ+)species formic acid *OCHO intermediate metal-support interactions

Model gradient: unified model and policy learning in model-based reinforcement learning

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Frontiers of Computer Science 2024年第4期18卷 117-128页

作者： chengxing jia Fuxiang zhang Tian XU Jing-cheng PANG Zongzhang zhang Yang YU National Key Laboratory for Novel Software Technology Nanjing UniversityNanjing 210023China Polixir Technologies Nanjing 210000China

Model-based reinforcement learning is a promising direction to improve the sample efficiency of reinforcement learning with learning a model of the *** model learning methods aim at fitting the transition data,and commonly employ a supervised learning approach to minimize the distance between the predicted state and the real *** supervised model learning methods,however,diverge from the ultimate goal of model learning,i.e.,optimizing the learned-in-the-model *** this work,we investigate how model learning and policy learning can share the same objective of maximizing the expected return in the real *** find model learning towards this objective can result in a target of enhancing the similarity between the gradient on generated data and the gradient on the real *** thus derive the gradient of the model from this target and propose the Model Gradient algorithm(MG)to integrate this novel model learning approach with policy-gradient-based policy *** conduct experiments on multiple locomotion control tasks and find that MG can not only achieve high sample efficiency but also lead to better convergence performance compared to traditional model-based reinforcement learning approaches.

关键词： reinforcement learning model-based reinforcement learning Markov decision process

Pressure transient characteristics of non-uniform conductivity fractured wells in viscoelasticity polymer flooding based on oil-water two-phase flow

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Petroleum Science 2024年第1期21卷 343-351页

作者： Yang Wang jia zhang Shi-Long Yang Ze-Xuan Xu Shi-Qing cheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil *** contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective ***,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant *** this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer *** hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer *** combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir *** with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore *** field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and th

关键词： Polymer flooding Non-Newtonian fluid Non-uniform fracture conductivity Two-phase flow Pressure transient analysis

Optimization of the co-closing law of guide vanes and blades for bulb turbines based on CFD

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Journal of Hydrodynamics 2024年第2期36卷 363-377页

作者： Hui Liu Yun-fa Lin Yong-guang cheng Song Xue Mao-jia Tang jian zhang jia-yi Fan State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China Dongfang Electric Machinery Co. Ltd.Deyang618000China

The load rejection transient process of bulb turbine units is critical to safety of hydropower stations,and determining appropriate closing laws of guide vanes(GVs)and runner blades(RBs)for this process is of *** this study,we proposed a procedure to optimize the co-closing law of GVs and RBs by using computational fluid dynamics(CFD),combined with the design of experiment(DOE)method,approximation model,and genetic optimization *** sensitivity of closing law parameters on the histories of head,speed,and thrust was analyzed,and a two-stage GVs’closing law associating with a linear RBs’closing law was *** results show that GVs dominate the transient characteristics by controlling the change of *** GVs’first-stage closing speed while shortening first-stage closing time can not only significantly reduce the maximum rotational speed but also suppress the water hammer pressure;slowing GVs’second-stage closing speed is conducive to controlling the maximum reverse axial *** directly affect the runner *** RBs’closing speed can further reduce the rotational speed and the maximum reverse axial *** safety margin of each control parameter,flow patterns,and pressure pulsations of a practical hydropower station were all improved after optimization,demonstrating the effectiveness of this method.

关键词： Bulb turbine load rejection transient process double regulation closing law optimization computational fluid dynamics(CFD)