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Effect of Carbon and Nitrogen Availability on Metabolism of Amino Acids in Germinating Spores of Arbuscular Mycorrhizal Fungi

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Pedosphere 2011年第4期21卷 432-442页

作者： JIN Hai-ru JIANG Dong-hua ZHANG Ping-hua College of Chemistry and Life Science Zhejiang Normal University Jinhua 321004 (China)

The effects of carbon （C） and nitrogen （N） sources on N utilization and biosynthesis of amino acids were examined in the germinating spores of the arbuscular mycorrhizal （AM） fungus Glomus intraradices Schenck ＆ Smith after exposure to various N substrates, CO2, glucose, and/or root exudates. The N uptake and de novo biosynthesis of amino acids were analyzed using stable isotopic labeling with mass spectrometric detection. High-performance liquid chromatography-based analysis was used to measure amino acid levels. In the absence of exogenous N sources and in the presence of 25 mL L^-1 CO2, the germinating AM fungal spores utilized internal N storage as well as C skeletons derived from the degradation of storage lipids to biosynthesize the free amino acids, in which serine and glycine were produced predominantly. The concentrations of internal amino acids increased gradually as the germination time increased from 0 to 1 or 2 weeks. However, asparagine and glutamine declined to the low levels; both degraded to provide the biosynthesis of other amino acids with C and N donors. The availability of exogenous inorganic N （ammonium and nitrate） and organic N （urea, arginine, and glutamine） to the AM fungal spores using only CO2 for germination generated more than 5 times more internal free amino acids than those in the absence of exogenous N. A supply of exogenous nitrate to the AM fungal spores with only CO2 gave rise to more than 10 times more asparagine than that without exogenous N. In contrast, the extra supply of exogenous glucose to the AM fungal spores generated a significant enhancement in the uptake of exogenous N sources, with more than 3 times more free amino acids being produced than those supplied with only exogenous CO2. Meanwhile, arginine was the most abundant free amino acid produced and it was incorporated into the proteins of AM funsal spores to serve as an N storage compound.

关键词： biosynthesis exogenous C and N sources isotopic labeling N uptake N storage compound

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Asymmetric interfacial engineering regulated charge distribution on ru/Ni-N-C sites for efficient hydrogen evolution reaction in alkaline and seawater electrolytes

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Science China Chemistry 2025年

作者： rui Yu Xi cao Chengyang Zhu Qingqing Chen Ziyi Yan Binbin Jiang Junjie Mao Xianwen Wei Key Laboratory of Electrochemical Clean Energy of Anhui Higher Education Institutes College of Chemistry and Materials ScienceAnhui Normal University Anhui Provincial Key Laboratory of Advanced Catalysis and Energy Materials School of Chemistry and Chemical Engineering Anqing Normal University School of Chemistry and Chemical Engineering Anhui University of Technology

Developing highly efficient and cost-effective electrocatalysts for hydrogen evolution reaction（HER） is grandly challenging in alkaline and alkaline seawater electrolytes. Herein, the asymmetric interfacial active sites with ru nanoparticles and Ni single atoms in ru/Ni-N-C were designed through a solvothermal-pyrolysis process. Constructing highly asymmetric interfacial active sites with a strong electron delocalization effect significantly improves HER kinetics. As expected, ru/Ni-N-C requires low overpotentials with around 20 mV at 10 mA cm-2and robust durability over 48 h in alkaline and alkaline seawater *** at 200 mA cm-2, the overpotentials are close to 100 mV in both above electrolytes for ru/Ni-N-C. Density function theory calculation results suggest that the asymmetric interface between ru nanoparticle and Ni-N-C could accelerate the dissociation of water molecules and modulate the hydrogen species, consequently improving the HER performances. This work opens a unique approach for constructing advanced materials for energy conversion.

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S空位及非金属掺杂单层Bi_(2)S_(2)Se的第一性原理研究

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原子与分子物理学报 2025年第1期42卷 127-134页

作者：张建华王敏陈畅曹倩徐银湖北大学资源环境学院武汉430062

Bi_(2)S_(2)Se是一种新兴的具有优异光电性能的材料,因此受到了广泛的关注.本研究采用第一性原理方法和开源程序,研究了本征单层Bi_(2)S_(2)Se以及掺杂非金属元素X(X=P,Cl,Br和I)和S空位的体系的电子结构和光学特性.计算结果表明,改性... 详细信息

Bi_(2)S_(2)Se是一种新兴的具有优异光电性能的材料,因此受到了广泛的关注.本研究采用第一性原理方法和开源程序,研究了本征单层Bi_(2)S_(2)Se以及掺杂非金属元素X(X=P,Cl,Br和I)和S空位的体系的电子结构和光学特性.计算结果表明,改性后出现了晶格缺陷.含S空位和P、Cl、Br掺杂体系的带隙减少,而I掺杂体系的带隙增加.同时,含S空位和Cl、Br、I掺杂体系的费米能级穿过导带底,而P掺杂体系的费米能级穿过价带顶.所有改性体系在费米能级附近都出现了缺陷能级或杂质能级,表现出较高的可见光吸收能力和散射能力,改性体系的对可见光的吸收能力和散射能力有所增加.

关键词： Bi_(2)S_(2)Se 掺杂电子结构光学性质第一性原理

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Transport patterns and numerical simulation of heavy metal pollutants in soils of lead–zinc ore mines

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Journal of Mountain Science 2021年第9期18卷 2345-2356页

作者： cao Jie XIE Cheng-yu HOU Zhi-ru College of Environment and Resources Xiangtan UniversityXiangtan 411105China School of Metallurgy and Environment Central South UniversityChangsha 410083China

Exploring transport patterns of soil contaminants is essential for solving the problem of heavy metal contamination in mine *** this study,contamination of Pb,Zn,and Cd in the mountain soils of the lead–zinc ore mines in Ganxi Township,Hengdong County,Hunan Province,China was investigated,and their transport patterns were further explored using a soil-column model and numerical simulation *** total,111 mine soil samples were collected and placed into six experimental soil *** controlling the water flow,a control soil column group(CK),two mixed soil columns X1 with daily water flows of 1 and 5 L,and three mixed soil columns X3 with daily water flows of 2,3,and 4 L were *** results showed that the residual fraction of Pb accounted for 71.93%of the content on average,whereas the exchangeable fractions of Zn,Cd,and Fe-Mn oxide-bound fractions of Zn and Cd accounted for 28.60%,31.07%,and 43.2%and 53.54%of the content,***,Zn,and Cd in the soils of the CK,X1,and X3 groups mainly were accumulated at a depth from approximately 0 to 20 cm,and the content at this depth accounted for 60.09%of that at a 0~40 cm *** soil at a depth range of 0~10 cm was most seriously contaminated,and the proportion of content was 32.39%of that at a 0~40 cm *** simulation showed that on the 5 th day,the pollutant transport range was 0~24 cm,and on the 9 th day,the pollutant transport range exceeded 40 *** the 15 th day,the transport capacity of pollutants at depths of 0~40 cm was close to the stable state,but the soil at a depth of 0~10 cm was still heavily *** results reflect the transport pattern of heavy metal pollutants in the soil of lead–zinc ore mines and may provide a reliable scientific support for the prevention of heavy metal contamination in mine environments.

关键词： Mountain Mine soil Heavy metals Numerical simulations Pollutants Transport patterns

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The Effect of the Cyp19a1 Gene Methylation Modification on Temperature-dependent Sex Determination of Reeves' Turtle(Mauremys reevesii)

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Asian Herpetological Research 2017年第3期18卷 213-220页

作者： Wenxiu ru Liushuai hua Yufeng WEI Weiye LI Dainan cao Yan GE Hong CHEN Xianyong LAN Shiping GONG Shaanxi Key Laboratory of Molecular Biology for Agriculture College of Animal Science and TechnologyNorthwest A&F University Guangdong Key Laboratory of Animal Conservation and Resource Utilization Guangdong Public Laboratory of Wild Animal Conservation and UtilizationGuangdong Institute of Applied Biological Resources Henan Key Laboratory of Farm Animal Breeding and Nutritional Regulation Institute of Animal Husbandry and Veterinary ScienceHenan Academy of Agricultural Sciences

Temperature-dependent sex determination（TSD） is a type of environmental sex determination in which the sex of the embryos depends on the ambient temperature; however,the molecular mechanisms governing this process remain ***,encoded by the cyp19a1 gene,which converts androgens into estrogens in animals,was considered to be the key gene for *** this study,the 5＇-flanking region of the cyp19a1 gene in Reeves＇ turtle（Mauremys reevesii） was cloned,and the promoter region was identified using the luciferase reporter *** the eggs of Reeves＇ turtle were incubated at different temperatures（26°C： male-biased temperature; 29°C： non-sex-biased temperature and 32°C： female-biased temperature）.During the thermosensitive period,the adrenal kidney gonad complexes（AKG） were *** methylation analysis of the AKG samples showed that the promoter region of the cyp19a1 gene was significantly de-methylated in the female-biased temperature regime（P＆lt;0.01）.Quantitative analysis of the cyp19a1 gene and estrogen by q PCR and Elisa assay showed that the expression level of the cyp19a1 gene and estrogen content were both upregulated significantly at the female-biased temperature（P＆lt;0.01）.These results indicated that the de-methylation response of the cyp19a1 gene to incubation temperature,especially at the female-biased temperature,could lead to temperature-specific expression of aromatase and increased estrogen levels,which may further determine gonadal development in Reeves＇ *** findings provide insights into the genetic mechanisms underlying TSD.

关键词： Reeves' turtle Mauremys reevesii temperature-dependent sex determination (TSD) cyp19a1 gene,methylation

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Integral precession calibration method of PIGA on linear vibration table

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Chinese Journal of Aeronautics 2024年第3期37卷 219-236页

作者： Chuang SUN Shun-qing REN Jun-wei cao ru HUO Department of Automation Tsinghua UniversityBeijing 100084China School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Faculty of Information technology Beijing University of TechnologyBeijing 100124China

Linear vibration table can provide harmonic accelerations to excite the nonlinear error terms of Pendulous Integrating Gyro Accelerometer(PIGA).Integral precession calibration method is proposed to calibrate PIGA on a linear vibration table in this *** on the precise expressions of PIGA’s inputs,the error calibration model of PIGA is *** angular velocity errors of PIGA are suppressed by integer periodic precession and the errors caused by non-integer periods vibrating are *** complete calibration process,including planning,preparation,PIGA testing,and coefficient identification,is designed to optimize the test operations and evaluate the calibration *** effect of the main errors on calibration uncertainty is analyzed and the relative sensitivity function is proposed to further optimize the test *** and simulation results verify that the proposed 10-position calibration method can improve calibration uncertainties after compensating for the related *** order of calibration uncertainties of the second-and third-order coefficients are decreased to 10^(-8)(rad.s^(-1))/g^(2)and 10^(-8)(rad.s^(-1))/g3,*** with the other two classical calibration methods,the calibration uncertainties of PIGA’s nonlinear error coefficients can be effectively reduced and the proportional residual errors are decreased less than 3×10-6(rad.s^(-1))/g by using the proposed calibration method.

关键词： PIGA Linear vibration table Vibration measurement Calibration Error analysis Uncertainty analysis

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Investigation of Scale Exponents of Complete and Incomplete Aggregation-Annihilation Processes

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Communications in Theoretical Physics 2004年第2X期42卷 299-302页

作者： huaNGBi-hua LIUCui-Mei YANGZhan-ru CollegeofPhysicsandTechnologyEngineering FuzhouUniversityFuzhou350001China DepartmentofPhysics ShangqiuNormalCollegeShangqiu476000China DepartmentofPhysicsandInstituteofTheoreticalPhysics BeijingNormalUniversityBeijing100875China

The complete and incomplete aggregation-annihilation processes are investigated with the method of generating function, and the scale exponents are obtained exactly. We find that the scale exponents of incomplete aggregation-annihilation process are different from the previous exponents obtained by different methods. The time dependence of the total number of clusters and the total mass of clusters are analytically obtained.

关键词：完全聚合-湮没过程不完全聚合-湮没过程标度指数线束质量分布平均场近似

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Applying System Thinking to Learn from Accident of Modern Automatic Control Systems

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Chinese Journal of Electronics 2014年第2期23卷 409-414页

作者： NIU ru cao Yuan GE Xiaocheng TANG Tao State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University School of Electronics and Information Engineering National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University Department of Computer Science University of York

Modern societies increasingly rely on automatic control systems. These systems are hardly pure technical systems; instead they are complex socio-technical systems, which consist of technical elements and social components. It is necessary to have a systematic approach to analyze these systems because it is growing evidence that accidents from these systems usually have complex causal factors which form an interconnected network of events,rather than a simple cause-effect chain. We take railway Train control systems(TCS) as an example to demonstrate the importance of the socio-technical approach to analyze the system. The paper presents an investigation of recent high-speed railway accident by applying STAMP – one of the most notable socio-technical system analysis techniques, outlines improvements to the system which could avoid similar accidents in the future. We also provide our valuable feedback for the use of STAMP.

关键词： Socio-technical automatic system Railway safety Accident analysis Systems theoretic accident model and processes(STAMP)

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The Impacts of Drug Price Regulations in China

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Journal of Systems Science and Systems Engineering 2019年第6期28卷 674-693页

作者： Yi Liu Juliang Zhang TCECheng Yihong ru Guowei hua Strategic Planning Department/PICC Research Institute of People's Insurance Company(Group)of China Limited Beijing 100031China School of Economics and Management Beijing Jiaotong UniversityBeijing 100044China Department of Logistics and Maritime Studies The Hong Kong Polytechnic UniversityKowloonHong KongChina

To lower pharmaceutical expenditure,the Chinese government has replaced the Fixed Percent Markup (FPM) policy with the policies of the Separation of Outpatient Pharmacies from Hospitals (SOPH) and the Zero Markup Drug (ZMD).We build a multistage game theoretic model comprising a hospital and a drugstore to analyze the policies' impacts on the providers' drug selection and pricing *** comparing the equihibrium outcomes,we draw the following conclusions:(i) FPM,especially for one imposing a strict margin ceiling,actually induces an expensive prescription given patients' great compliance.(ii) Both SOPH and ZMD can conditionally lower patients' expenditure,and their performances rely on the hospital's selection.(iii) A proper rate of insurance coverage and a removal of drug rebate are helpful to improve the policies' performance.

关键词： Drug price regulations patients' expenditure healthcare reform game theory

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Event-triggered model-free adaptive control for a class of surface vessels with time-delay and external disturbance via state observer

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Journal of Systems Engineering and Electronics 2023年第3期34卷 783-797页

作者： CHEN hua SHEN Chao huaNG Jiahui cao Yuhan College of Science Hohai UniversityNanjing 210098China College of Mechanical and Electrical Engineering Hohai UniversityChangzhou 213022China Hohai-Lille College Hohai UniversityNanjing 211100China

This paper provides an improved model-free adaptive control(IMFAC)strategy for solving the surface vessel trajectory tracking issue with time delay and restricted ***,the original nonlinear time-delay system is transformed into a structure consisting of an unknown residual term and a parameter term with control inputs using a local compact form dynamic linearization(local-CFDL).To take advantage of the resulting structure,use a discrete-time extended state observer(DESO)to estimate the unknown residual ***,according to the study,the inclusion of a time delay has no effect on the linearization structure,and an improved control approach is provided,in which DESO is used to adjust for ***,a DESO-based event-triggered model-free adaptive control(ET-DESO-MFAC)is established by designing event-triggered conditions to assure Lyapunov *** when the system’s indicator fulfills the provided event-triggered condition will the control input signal be updated;otherwise,the control input will stay the same as it is at the last trigger moment.A coordinate compensation approach is developed to reduce the steady-state inaccuracy of trajectory ***,simulation experiments are used to assess the effectiveness of the proposed technique for trajectory tracking.

关键词： surface vessels event-triggered condition(ETC) discrete-time extended state observer(DESO) model-free adaptive control(MFAC) coordinate compensation

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