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Subchronic Oral Toxicity Evaluation of Lanthanum： A 90-day, Repeated Dose Study in Rats

Biomedical and Environmental Sciences 2018年第5期31卷 363-375页

作者： FANG Hai Qin YU Zhou ZHI Yuan FANG Jin LIChen Xi WANG Yi Mei peng shuang qing JIA Xu Dongl Key Laboratory of Food Safety Risk Assessment of Ministry of Health China National Center for Food Safety Risk AssessmentBeijing 100021China Evaluation and Research Centre for Toxicology Institute of Disease Control and PreventionAcademy of Military Medical SciencesBeijing 100071China

Objective The present study was undertaken to evaluate the subchronic toxicity of lanthanum and to determine the no observed adverse effect level（NOAEL）,which is a critical factor in the establishment of an acceptable dietary intake（ADI）.Methods In accordance with the Organization for Economic Co-operation and Development（OECD） testing guidelines,lanthanum nitrate was administered once daily by gavage to Sprague-Dawley（SD） rats at dose levels of 0,1.5,6.0,24.0,and 144.0 mg/kg body weight（BW） per day for 90 days,followed by a recovery period of 4 weeks in the 144.0 mg/kg BW per day and normal control *** parameters were mortality,clinical symptoms,body and organ weights,serum chemistry,and food consumption,as well as ophthalmic,urinary,hematologic,and histopathologic *** benchmark dose（BMD） approach was applied to estimate a point of departure for the hazard risk assessment of *** Significant decreases were found in the 144.0 mg/kg BW group in the growth index,including body weight,organ weights,and food *** study suggests that the NOAEL of lanthanum nitrate is 24.0 mg/kg BW per ***,the 95% lower confidence value of the benchmark dose（BMDL） was estimated as 9.4 mg/kg BW per day in females and 19.3 mg/kg BW per day in *** The present subchronic oral exposure toxicity study may provide scientific data for the risk assessment of lanthanum and other rare earth elements（REEs）.

关键词： Lanthanum Subchronic toxicity 90-day repeated oral dose test No observed adverse effectLevel Acceptable dietary intake Benchmark dose

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Preliminary results of solving the problem of geometric distortion for the 2.4 m telescope at Yunnan Observatory

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Research in Astronomy and Astrophysics 2012年第10期12卷 1451-1456页

作者： qing-Feng Zhang qing-Yu peng Zi Zhu Department of Computer Science Jinan University Guangzhou 510632 China Key Laboratory of Modem Astronomy and Astrophysics (Nanjing University) Ministry ofEducation Nanjing 210032 China Sino-French Joint Laboratory for Astrometry Dynamics and Space Science Jinan UniversityGuangzhou 510632 China

We observed the open clusters NGC 1664 （43 exposures） and M35 （42 ex- posures） by the Yunnan Faint Object Spectrograph and Camera in the 2.4 m telescope at Yunnan Astronomical Observatory on 2011 January 3, and processed them by a method recently proposed by us. The result shows that there is a geometric distortion effect in the field of view and the maximum distortion is - 0.25 （i.e. 1 pixel）. After correcting the geometric distortion, the precision of stellar positional measurement is significantly improved. The best precision in each direction is 6 mas for well-exposed stars.

关键词： astrometry -- methods: data analysis -- techniques: image processing

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Potential energy surface and formation of superheavy nuclei with the Skyrme energy-density functional

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Communications in Theoretical Physics 2022年第5期74卷 97-105页

作者： Cheng peng Zhao-qing Feng School of Physics and Optoelectronics South China University of TechnologyGangzhou 510640 China

With the Skyrme energy-density functional theory,the nucleus–nucleus potential is calculated and the potential energy surface is obtained with different effective forces for accurately estimating the formation cross sections of superheavy nuclei in massive fusion *** width and height of the potential pocket are influenced by the Skyrme effective forces SkM,SkM^(*),SkP,SIII,Ska,and SLy4,which correspond to the different equations of state for the isospin symmetry nuclear *** is found that the nucleus–nucleus potential is associated with the collision orientation and Skyrme forces.A more repulsive nuclear potential is pronounced with increasing the incompressible modulus of nuclear matter,which hinders the formation of superheavy *** available data in the fusion-evaporation reaction of ^(48)Ca+^(238)U are nicely reproduced with the SkM^(*) parameter by implementing the potential into the dinuclear system model.

关键词： Skyrme force nucleus-nucleus potential energy density functional DNS model

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Ferroptosis in ischemic stroke:Animal models and mechanisms

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Zoological Research 2024年第6期45卷 1235-1248页

作者： qing-Zhang Tuo peng Lei Department of Geriatrics and State Key Laboratory of Biotherapy National Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengduSichuan 610041China Department of Neurology and State Key Laboratory of Biotherapy National Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengduSichuan 610041China

Stroke is a major cause of death and disability worldwide,with the majority of cases resulting from ischemic events due to arterial *** therapeutic approaches focus on rapid reperfusion through intravenous thrombolysis and intravascular *** these interventions can mitigate long-term disability,reperfusion itself may induce neuronal *** exact mechanisms underlying neuronal damage following cerebral ischemia have yet to be *** research suggests that ferroptosis may play a significant role in post-ischemic neuronal death,which can be targeted to prevent neuronal *** review explores the three essential hallmarks of ferroptosis:the presence of redox-active iron,the peroxidation of polyunsaturated fatty acid-containing phospholipids,and the loss of lipid peroxide repair *** involvement of ferroptosis in neuronal injury following ischemic stroke is also explored,along with an overview of ferroptosis-associated changes in different ischemic stroke animal ***,recent therapeutic interventions targeting the ferroptosis pathway,as well as the opportunities,difficulties,and future directions of ferroptosis-targeted therapies in ischemic stroke,are discussed.

关键词： Ischemic stroke Ferroptosis Animal models Iron deposition Lipid peroxidation

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Cooling hot rolling steel strip using combined tactics

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Journal of University of Science and Technology Beijing 2008年第3期15卷 362-365页

作者： Li peng qing Li Zhou Zhou School of Communication and Control Engineering Jiangnan University Wuxi 214122 China School of Information Engineering University of Science and Technology Beijing Beijing 100083 China

The coiling temperature control of a typical steel strip mill was investigated. Due to the high speed of a strip and complex circumstance, it is very hard to set up a cooling model with high accuracy. A simplified dynamic model was proposed, based on which a cooling control scheme with combined feedforward, feedback and adaptive algorithms was developed. Meanwhile, the genetic algorithms were used for the optimization of model parameters. Simulations with a model validated using actual plant data were conducted, and the results have confirmed the effectiveness of the proposed control methods. At last, a simulation system for coiling temperature control was developed. It can be used for new product trials and newcomer training.

关键词： coiling temperature temperature control feedforward feedback adaptive algorithm simulation

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An improved solution to geometric distortion using an orthogonal method

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Research in Astronomy and Astrophysics 2017年第2期17卷 89-96页

作者： Huan-Wen peng qing-Yu peng Na Wang Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Department of Computer Science Jinan University Guangzhou 510632 China University of Chinese Academy of Sciences Beijing 100049 China Sino-French Joint Laboratory for Astrometry Dynamics and Space Science Jinan University Guangzhou 510632 China

The geometric distortion of a CCD field of view has a direct influence on the positional measurements of CCD observations. In order to obtain high precision astrometric results, the geometric distortion should be derived and corrected precisely. As presented in our previous work, a convenient solution has been carried out and has also been applied to observations of Phoebe. In order to fur- ther improve the solution, an orthogonal method based on Zernike polynomials is used in this work. Four nights of CCD observations including Himalia, the sixth satellite of Jupiter, and open clusters （NGC 1664 or NGC 2324） on each night have been processed as an application. The observations were obtained from the 2.4 m telescope administered by Yunnan Observatories. The catalog UCAC4 was used to match reference stars in all of the CCD frames. The ephemeris of Himalia is retrieved from the Institut de M6canique C61este et de Calcul des Ephemerides （IMCCE）. Our results show that the means of observed minus calculated （O - C） positional residuals are -0.034 and -0.026 arcsec in right ascension and declination, respectively. The corresponding standard deviations are 0.031＂ and 0.028＂. The measurement dispersion is significantly improved compared to that by using our previous solution.

关键词： astrometry -- planets and satellites: individual (Himalia) -- methods: observational

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Preliminary results of CCD observations targeting Himalia acquired at Yunnan Observatories in 2015

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Research in Astronomy and Astrophysics 2016年第12期16卷 59-66页

作者： Huan-Wen peng Na Wang qing-Yu peng Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China

In order to study the potential associated with high precision CCD astrometry of irregular satel- lites, we have acquired experimental observations of Himalia, the sixth and irregular satellite of Jupiter. A total of 185 CCD observations were obtained by using the 2.4m and 1 m telescopes administered by Yunnan Observatories over ten nights. Preliminary analysis of the observations were made, including geo- metric distortion, atmospheric refraction, and also the phase effect. All positions of Himalia are measured relative to the reference stars from the catalog UCAC4 in each CCD field of view. The theoretical positions of Himalia were retrieved from the Institute de M6chanique C61este et de Calcul des t^ph6m6rides, while the positions of Jupiter were obtained based on the planetary ephemeris INPOP13c. The results show that the means of observed minus computed （O - C） residuals are -0.004＂ and -0.002＂ in right ascension and declination, respectively. The standard deviations of （O - C） residuals are estimated to be about 0.04＂ in each direction.

关键词： astrometry -- planets and satellites: individual (Himalia) -- methods: observational

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From Fluorescent Probes to the Theranostics Platform

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Chinese Journal of Chemistry 2022年第16期40卷 1964-1974页

作者： peng Wei qing Wang Tao Yi State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative MedicineCollege of ChemistryChemical Engineering and BiotechnologyDonghua UniversityShanghai201620 China Department of Chemistry Fudan UniversityShanghai200438 China

Since the advent of fluorescent probes,they have been widely used in the field of life *** probes can not only light up the cells,tissues and organs,but also be used to explore the bio-distribution of specific types of disease ***,the development of new fluorescent probes capable of recognition of bio-markers is extremely important for the diagnosis of the related ***,we focus on our recent works experienced the evolution from the beginning of simply fluorescent probes to the construction of theranostics *** have developed a series of new fluorescent probes for the detecting and imaging of reactive oxygen species(ROS)and specific enzymes in vitro and in living *** the shift of the fluorescence signal from visible to near-infrared region,we expanded the application of the fluorescent probes from in vitro to in *** recently,we further constructed theranostics platforms to combine the diagnosis immediately with the corresponding treatment.

关键词： Fluorescent probes Imaging agents Prodrugs Theranostics platform Nanoparticles

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Self-Consistent Flow Shear Induced by Drift-Thermal Turbulence

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Chinese Physics Letters 1996年第8期13卷 598-601页

作者： peng Xiao-dong GAO qing-di Southwestern Institute of Physics Chengdu 610041

The self-consistent poloidal flow shear induced by turbulence driven by impurity radiation has been studied analytically. A set of reduced equations is obtained. In our system, three equilibrium states exist. The first is the zero flow shear state, which is relevant to the behavior such as L mode, the second is the positive flow shear state, which is relevant to the behavior such as dithering H mode, and the third is the negative flow shear state, which is relevant to the behavior such as edge-localized modes.

关键词： flow Shear turbulence

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Systematics on production of superheavy nuclei Z=119-122 in fusion-evaporation reactions

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Nuclear Science and Techniques 2021年第10期32卷 59-71页

作者： Fei Niu peng-Hui Chen Zhao-qing Feng School of Physics and Optoelectronic Technology South China University of TechnologyGuangzhou 510640China College of Electrical Energy and Power Engineering Yangzhou UniversityYangzhou 225000China

The fusion dynamics of the formation of super-heavy nuclei were investigated thoroughly within the din-uclear system *** Monte Carlo approach was implemented in the nucleon transfer process to include all possible orientations,at which the dinuclear system is assumed to be formed at the touching configuration of dinuclear *** production cross sections of superheavy nuclei Cn,Fl,Lv,Ts,and Og were calculated and compared with the available data from *** evaporation residue excitation functions in the channels of pure neutrons and charged particles were systematically *** combinations of 44 Sc,48;50 Ti,49;51 V,52;54 Cr,58;62 Fe,and 62;64 Ni bombarding the actinide nuclides 238 U,244 Pu,248 Cm,247;249 Bk,249;251 Cf,252 Es,and 243 Am were calculated to produce the superheavy elements with Z¼119?*** obtained that the production cross sections sensitively depend on the neutron richness of the reaction *** structure of the evaporation residue excitation function is related to the neutron separation energy and fission barrier of the compound nucleus.

关键词： Dinuclear system model Fusion-evaporation reactions Superheavy nuclei Cross sections

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