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In maize,co-expression of GAT and GR79-EPSPS provides high glyphosate resistance,along with low glyphosate residues

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aBIOTECH 2023年第4期4卷 277-290页

作者： Shengyan li Pengcheng Li Xiangyin li Ning Wen Yinxiao Wang Wei Lu Min lin Zhihong Lang Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijingChina National Nanfan Research Institute(Sanya) Chinese Academy of Agricultural SciencesSanyaHainanChina

Herbicide tolerance has been the dominant trait introduced during the global commercialization of genetically modified(GM)crops.Herbicide-tolerant crops,especially glyphosate-resistant crops,offer great advantages for weed management;however,despite these benefits,glyphosate-resistant maize(Zea mays L.)has not yet been commercially deployed in China.To develop a new bio-breeding resource for glyphosate-resistant maize,we introduced a codon-optimized glyphosate N-acetyltransferase gene,gat,and the enolpyruvyl-shikimate-3-phosphate synthase gene,gr79-epsps,into the maize variety B104.We selected a genetically stable high glyphosate resistance(GR)transgenic event,designated GG2,from the transgenic maize population through screening with high doses of glyphosate.A molecular analysis demonstrated that single copy of gat and gr79-epsps were integrated into the maize genome,and these two genes were stably transcribed and translated.Field trials showed that the transgenic event GG2 could tolerate 9000 g acid equivalent(a.e.)glyphosate per ha with no effect on phenotype or yield.A gas chromatography-mass spectrometry(GC–MS)analysis revealed that,shortly after glyphosate application,the glyphosate(PMG)and aminomethylphosphonic acid(AMPA)residues in GG2 leaves decreased by more than 90%compared to their levels in HGK60 transgenic plants,which only harbored the epsps gene.Additionally,PMG and its metabolic residues(AMPA and N-acetyl-PMG)were not detected in the silage or seeds of GG2,even when far more than the recommended agricultural dose of glyphosate was applied.The co-expression of gat and gr79-epsps,therefore,confers GG2 with high GR and a low risk of herbicide residue accumulation,making this germplasm a valuable GR event in herbicide-tolerant maize breeding.

关键词： Transgenic maize Glyphosate resistance Gr79-epsps gene Gat gene Low residues

Effects of a phase transition on two-pion interferometry in heavy ion collisions at √SNN=2.4-7.7 GeV

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Science China(Physics,Mechanics & Astronomy) 2023年第3期66卷 88-97页

作者： Pengcheng Li Jan Steinheimer Tom Reichert Apiwit Kittiratpattana Marcus Bleicher Qingfeng li Institut fur Theoretische Physik Johann Wolfgang Goethe Universitat FrankfurtFrankfurt am Main 60438Germany School of Science Huzhou UniversityHuzhou 313000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Frankfurt Institute for Advanced Studies Frankfurt am Main 60438Germany GSI Helmholtzzentrum f¨urSchwerionenforschung GmbH Darmstadt 64291Germany Helmholtz Research Academy Hesse for FAIR(HFHF) GSI Helmholtz Center for Heavy Ion PhysicsCampus FrankfurtFrankfurt am Main 60438Germany Center of Excellence in High Energy Physics&Astrophysics School of PhysicsSuranaree University of TechnologyNakhon Ratchasima 30000Thailand

Hanbury-Brown-Twiss(HBT) correlations for charged pions in central Au+Au collisions at √SNN=2.4-7.7 GeV(corresponding to beam kinetic energies in the fixed target frame from Elab=1.23 to 30 GeV/nucleon) are calculated using the ultra-relativistic quantum molecular dynamics model with different equations of state(EoSs).The effects of a phase transition at high baryon densities are clearly observed in the explored HBT parameters.The results show that the available data on the HBT radii,RO/RSand R^(2)_(O)-R^(2)_(S),in the investigated energy region favor a relatively stiff EoS at low beam energies,which then turns into a soft EoS at high collision energies consistent with astrophysical constraints on the high-density EoS of quantum chromodynamics(QCD).The specific effects of two different phase transition scenarios on RO/RSand R^(2)_(O)-R^(2)_(S)are investigated.A phase transition with a significant softening of the EoS below four times the nuclear saturation density can be excluded using HBT data.Our results highlight that the pion’s RO/RSand R^(2)_(O)-R^(2)_(S)are sensitive to the stiffness of the EoS and can be used to constrain and understand the QCD EoS in a high baryon density region.

关键词： heavy ion collisions HBT correlation equation of state

Flammable gases produced by TiO_(2) nanoparticles under magnetic stirring in water

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Friction 2022年第7期10卷 1127-1133页

作者： Pengcheng Li Chongyang TANG Xiangheng XIAO Yanmin JIA Wanping CHEN School of Physics and Technology Wuhan UniversityWuhan 430072China School of Science Xi'an University of Posts and TelecommunicationsXi'an 710054China

The friction between nanomaterials and Teflon magnetic stirring rods has recently drawn much attention for its role in dye degradation by magnetic stirring in dark.Presently the friction between TiO_(2) nanoparticles and magnetic stirring rods in water has been deliberately enhanced and explored.As much as 1.00 g TiO_(2) nanoparticles were dispersed in 50 mL water in 100 mL quartz glass reactor,which got gas-closed with about 50 mL air and a Teflon magnetic stirring rod in it.The suspension in the reactor was magnetically stirred in dark.Flammable gases of 22.00 ppm CO,2.45 ppm CH_(4),and 0.75 ppm H_(2) were surprisingly observed after 50 h of magnetic stirring.For reference,only 1.78 ppm CO,2.17 ppm CH_(4),and 0.33 ppm H_(2) were obtained after the same time of magnetic stirring without TiO_(2) nanoparticles.Four magnetic stirring rods were simultaneously employed to further enhance the stirring,and as much as 30.04 ppm CO,2.61 ppm CH_(4),and 8.98 ppm H_(2) were produced after 50 h of magnetic stirring.A mechanism for the catalytic role of TiO_(2) nanoparticles in producing the flammable gases is established,in which mechanical energy is absorbed through friction by TiO_(2) nanoparticles and converted into chemical energy for the reduction of CO_(2) and H_(2)O.This finding clearly demonstrates a great potential for nanostructured semiconductors to utilize mechanical energy through friction for the production of flammable gases.

关键词： friction magnetic stirring catalysis CO_(2)reduction TiO_(2)

Fast Blood Oxygenation through Hemocompatible Asymmetric Polymer of Intrinsic Microporosity Membranes

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Research 2024年第1期2023卷 261-270页

作者： Xinxi Huang Junping Huang pengcheng Su Wanbin li Guangdong Key Laboratory of Environmental Pollution and Health School of EnvironmentJinan UniversityGuangzhou 511443China

Membrane technology has attracted considerable attention for chemical and medical applications,among others.Artificial organs play important roles in medical science.A membrane oxygenator,also known as artificial lung,can replenish O_(2) and remove CO_(2) of blood to maintain the metabolism of patients with cardiopulmonary failure.However,the membrane,a key component,is subjected to inferior gas transport property,leakage propensity,and insufficient hemocompatibility.In this study,we report efficient blood oxygenation by using an asymmetric nanoporous membrane that is fabricated using the classic nonsolvent-induced phase separation method for polymer of intrinsic microporosity-1.The intrinsic superhydrophobic nanopores and asymmetric configuration endow the membrane with water impermeability and gas ultrapermeability,up to 3,500 and 1,100 gas permeation units for CO_(2) and O_(2),respectively.Moreover,the rational hydrophobic–hydrophilic nature,electronegativity,and smoothness of the surface enable the substantially restricted protein adsorption,platelet adhesion and activation,hemolysis,and thrombosis for the membrane.Importantly,during blood oxygenation,the asymmetric nanoporous membrane shows no thrombus formation and plasma leakage and exhibits fast O_(2) and CO_(2) transport processes with exchange rates of 20 to 60 and 100 to 350 ml m^(−2) min^(−1),respectively,which are 2 to 6 times higher than those of conventional membranes.The concepts reported here offer an alternative route to fabricate high-performance membranes and expand the possibilities of nanoporous materials for membrane-based artificial organs.

关键词： porosity asymmetric Oxygen

Spacelike framed curves with lightlike components and singularities of their evolutes and focal surfaces in Minkowski 3-space

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Acta Mathematica Sinica,English Series 2022年

作者： Pengcheng Li Donghe PEI Xin ZHAO School of Mathematics and Statistics Northeast Normal University

In this paper, we define the evolute and focal surface of a spacelike framed curve with lightlike components in Minkowski 3-space. It is a generalization of the previous results of regular spacelike curves, since singularities are allowed in the original spacelike curves studied by spacelike framed curves with lightlike components. Meanwhile, we show a new geometric invariant to characterise singularities of the focal surface. Then, the classification theorem and recognition theorem for the singularities of the focal surface in generic are also given.

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An insight on the mechanism of efficient leaching of vanadium from vanadium shale induced by microwave-generated hot spots

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International Journal of Minerals,Metallurgy and Materials 2023年第2期30卷 293-302页

作者： Sheng li Yimin Zhang Yizhong Yuan pengcheng Hu School of Resource and Environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control Wuhan University of Science and TechnologyWuhan 430081China Collaborative Innovation Center of Strategic Vanadium Resources Utilization Wuhan 430081China Hubei Provincial Engineering Technology Research Center of High Efficient Cleaning Utilization for Shale Vanadium Resource Wuhan University of Science and TechnologyWuhan 430081China School of Resource and Environmental Engineering Wuhan University of TechnologyWuhan 430070China

Microwave heating can rapidly and uniformly raise the temperature and accelerate the reaction rate.In this paper,microwave heating was used to improve the acid leaching,and the mechanism was investigated via microscopic morphology analysis and numerical simulation by COMSOL Multiphysics software.The effects of the microwave power,leaching temperature,CaF_(2) dosage,H_(2)SO_(4) concentration,and leaching time on the vanadium recovery were investigated.A vanadium recovery of 80.66%is obtained at a microwave power of 550 W,leaching temperature of 95℃,CaF_(2) dosage of 5wt%,H_(2)SO_(4) concentration of 20vol%,and leaching time of 2.5 h.Compared with conventional leaching technology,the vanadium recovery increases by 6.18%,and the leaching time shortens by 79.17%.More obvious pulverization of shale particles and delamination of mica minerals happen in the microwave-assisted leaching process.Numerical simulation results show that the temperature of vanadium shales increases with an increase in electric field(E-field).The distributions of E-field and temperature among vanadium shale particles are relatively uniform,except for the higher content at the contact position of the particles.The analysis results of scaleup experiments and leaching experiments indicate high-temperature hot spots in the process of microwave-assisted leaching,and the local high temperature destroys the mineral structure and accelerates the reaction rate.

关键词： vanadium shale microwave-assisted leaching hot spots numerical simulation

Conversion of biomass lignin to high-value polyurethane:A review

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Journal of Bioresources and Bioproducts 2020年第3期5卷 163-179页

作者： Hui li Yuan liang Pengcheng Li Chaobin He Hubei Key Laboratory of Plasma Chemistry and Advanced Materials School of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China Department of Materials Science&Engineering National University of Singapore9 Engineering Drive 1117574Singapore Institute of Materials Research and Engineering Agency for ScienceTechnologyand Research(A∗STAR)2 Fusionopolis WayInnovis 138634Singapore

lignin,as a major by-product of pulp and paper industry,has attracted extensive interest for the preparation of high value-added products,due to the merits of abundant,sustainable,inexpensive,and unique functional groups.This review focuses on the strategies to develop high performance polyurethane(PU)materials from lignin on the basis of main reports,in which lignin was used not only as macromonomer to substitute petroleum-based polyols,but also as blending filler for PU industry.Pre-treatment approaches,especially lignin fractions extracted with various solvents and chemical modifications,e.g.,depolymerization,hydroxyalkylation,dealkylation,and esterication,were widely explored to enable lignin more reactive and available to synthesize PU products.In addition,lignin/PU blends were also prepared to fulfill industrial demand.With adjustment of lignin structure,the PU formulation,and synthesis procedures,various lignin-based PU products with advanced properties and a higher bio-substitution ratio have been developed,demonstrating the potential industrial application of lignin for high value-added sustainable materials.

关键词： lignin Polyurethane Modification Bio-substitution

A novel intrusion detection model for the CAN bus packet of in-vehicle network based on attention mechanism and autoencoder

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Digital Communications and Networks 2023年第1期9卷 14-21页

作者： pengcheng Wei Bo Wang Xiaojun Dai li li Fangcheng He School of Mathematics and Information Engineering Chongqing University of EducationChongqingChina School of Automation Chongqing University of Posts and TelecommunicationsChongqingChina Department of Modern Service Chongqing Energy Industry Technician CollegeChongqingChina College of Foreign Languages literature Chongqing University of EducationChongqingChina

The attacks on in-vehicle Controller Area Network(CAN)bus messages severely disrupt normal communication between vehicles.Therefore,researches on intrusion detection models for CAN have positive business value for vehicle security,and the intrusion detection technology for CAN bus messages can effectively protect the invehicle network from unlawful attacks.Previous machine learning-based models are unable to effectively identify intrusive abnormal messages due to their inherent shortcomings.Hence,to address the shortcomings of the previous machine learning-based intrusion detection technique,we propose a novel method using Attention Mechanism and AutoEncoder for Intrusion Detection(AMAEID).The AMAEID model first converts the raw hexadecimal message data into binary format to obtain better input.Then the AMAEID model encodes and decodes the binary message data using a multi-layer denoising autoencoder model to obtain a hidden feature representation that can represent the potential features behind the message data at a deeper level.Finally,the AMAEID model uses the attention mechanism and the fully connected layer network to infer whether the message is an abnormal message or not.The experimental results with three evaluation metrics on a real in-vehicle CAN bus message dataset outperform some traditional machine learning algorithms,demonstrating the effectiveness of the AMAEID model.

关键词： Controller area network bus packet In-vehicle network Attention mechanism Autoencoder

Immunostimulatory eff ect of quaternary degree and acetyl group of quaternized chitosan on macrophages RAW 264.7

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Journal of Oceanology and limnology 2022年第3期40卷 1160-1170页

作者： Xiaomin li Rong’e XING Chaojie XU Song liU Yukun QIN Kecheng li Huahua YU Pengcheng Li CAS and Shandong Province Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266237China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

Hydroxypropyltrimethyl ammonium chloride chitosan(HACC)and hydroxypropyltrimethyl ammonium chloride fully deacetylated chitosan(De-HACC)were synthesized with various degrees of substitution by altering the ratio of chitosan to glycidyl trimethyl-ammonium chloride(GTMAC).The effects of the quaternary ammonium degree and the acetyl group of these polymers on immunostimulatory activities were detected in RAW 264.7 cells.The expression levels of nitrogen oxide(NO),interleukin-6(IL-6)and tumor necrosis factor(TNF-α)were compared.Results show that the removal of acetyl groups in chitosan obviously improved the degree of substitution of quaternary ammonium salts.In addition,HACC and De-HACC were capable of promoting immunological activity in a substitution-dependent manner;HACC was positively correlated,and De-HACC was negatively correlated.Among tested ratios,HACC-30%and De-HACC-54%performed better than the others,and De-HACC-54%performed the best.Generally,quaternized chitosan possesses immunostimulatory activity,which is related to the degree of quaternization and the acetyl group.

关键词： quaternized chitosan fully deacetylated quaternized chitosan degree of quaternization Immunostimulatory activity