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Assimilation of Chinese Fengyun-3B Microwave Temperature Sounder radiances into the Global GRAPES system with an improved cloud detection threshold

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Frontiers of Earth Science 2016年第1期10卷 145-158页

作者： juan LI Guiqing LIU Numerical Weather Prediction Center China Meteorological Administration Beijing 100081 China National Meteorological Center China Meteorological Administration Beijing 100081 China

Fengyun-3B （FY-3B） is the second polar- orbiting satellite in the new Fengyun-three series. This paper describes the assimilation of the FY-3B Microwave Temperature Sounder （MWTS） radiances in the Chinese Numerical Weather prediction system - the Global and Regional Assimilation and PrEdiction System （GRAPES）. A quality control procedure for the assimilation of the FY- 3B MWTS radiance was proposed. Extensive monitoring before assimilation shows that the observations of channel 4 are notably contaminated. Channels 2 and 3 are used in this research. A cloud detection algorithm with an improved cloud-detection threshold is determined and incorporated into the impact experiments. The clear field- of-view （FOV） percentage increased from 42% to 57% with the new threshold. In addition, the newly added FOVs are located in the clear region, as demonstrated by the cloud liquid water path data from NOAA-18. The impact of the MWTS radiances on the prediction of GRAPES was researched. The observation biases ofFY-3B MWTS O-B （differences between satellite observations and model simulations） significantly decreased after an empirical bias correction procedure. After assimilation, the residual biases are small. The assimilation of the FY-3B MWTS radiances shows a positive impact in the Northern Hemisphere and a neutral impact in the Southern Hemisphere.

关键词： Fengyun-3B (FY-3B) MWTS quality control GRAPES

Performance assessment of two-dimensional hydraulic models for generation of flood inundation maps in mountain river basins

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Water Science and Engineering 2019年第1期12卷 11-18页

作者： juan Pinos Luis Timbe Department of Water Resources and Environmental Sciences University of Cuenca

Hydraulic models for the generation of flood inundation maps are not commonly applied in mountain river basins because of the difficulty in modeling the hydraulic behavior and the complex topography. This paper presents a comparative analysis of the performance of four twodimensional hydraulic models (HEC-RAS 2D, Iber 2D, Flood Modeller 2D, and PCSWMM 2D) with respect to the generation of flood inundation maps. The study area covers a 5-km reach of the Santa B-arbara River located in the Ecuadorian Andes, at 2330 masl, in Gualaceo. The model's performance was evaluated based on the water surface elevation and flood extent, in terms of the mean absolute difference and measure of fit. The analysis revealed that, for a given case, Iber 2D has the best performance in simulating the water level and inundation for flood events with 20- and 50-year return periods, respectively, followed by Flood Modeller 2D, HEC-RAS 2D, and PCSWMM 2D in terms of their performance. Grid resolution, the way in which hydraulic structures are mimicked, the model code, and the default value of the parameters are considered the main sources of prediction uncertainty.

关键词： Two-dimensional hydraulic models Flood modeling Flood extent Water surface elevation High mountain river Ecuador

Synthesis and Crystal Structure of a New Nickel(II) Complex with Unsymmetric Quadridentate Schiff Base Containing Oxime

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Chinese Journal of Structural Chemistry 2005年第4期24卷 454-456页

作者： ZHANGGuo-juan FENGYun-Long GAOShan InstituteofPhysicalChemistry ZhejiangKeyLaboratoryforReactiveChemistryonSolidSurfacesZhejiangNormalUniversityJinhua321004China CollegeofChemistryandChemicalEngineering HeilongjiangUniversityHarbin150080China

The title complex, C18H15N3NiO3, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group Cc with a = 10.939(2), b = 22.909(5), c = 6.907(1) ?, β = 116.75(3)°, V = 1545.7(5) ?, Z = 4, Mr = 380.04, F(000) = 784, Dc = 1.633 g/cm3 and μ(MoKα) = 1.279 mm–1. The structure was refined to R = 0.0472 and wR = 0.0893 for 2571 observed reflections with I > 2σ(I). The absolute structure Flack parameter X is 0.01(2). In this crystal structure, strong face-to-face π-π stacking interactions between adjacent molecules lead to a one-dimensional chain structure.

关键词： nickel(II) complex Schiff base oxime crystal structure π-π stacking interaction

Cholesterol metabolism and homeostasis in the brain

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Protein & Cell 2015年第4期6卷 254-264页

作者： juan Zhang Qiang Liu Chinese Academy of Sciences Key Laboratory of Brain Function and Disease and School of Life Sciences University ofScience and Technoloqv of China. Hefei 230026. China

Cholesterol is an essential component for neuronal physiology not only during development stage but also in the adult life. Cholesterol metabolism in brain is in- dependent from that in peripheral tissues due to blood- brain barrier. The content of cholesterol in brain must be accurately maintained in order to keep brain function well. Defects in brain cholesterol metabolism has been shown to be implicated in neurodegenerative diseases, such as Alzheimer＇s disease （AD）, Huntington＇s disease （HD）, Parkinson＇s disease （PD）, and some cognitive deficits typical of the old age. The brain contains large amount of cholesterol, but the cholesterol metabolism and its complex homeostasis regulation are currently poorly understood. This review will seek to integrate current knowledge about the brain cholesterol metabo- lism with molecular mechanisms.

关键词： cholesterol metabolism homeostasis,apoE

Global Strong Solutions and Large-time Behavior of 2D Tropical Climate Model

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Acta Mathematicae Applicatae Sinica 2023年第4期39卷 886-925页

作者： Dong-juan NIU Ying WANG School of Mathematical Sciences Capital Normal UniversityBeijing 100048China School of Physical Science and Technology Guangxi UniversityNanning 530004China

In this paper we mainly deal with the global well-posedness and large-time behavior of the 2D tropical climate model with small initial data. We first establish the global well-posedness of solution in the Besov space, then we obtain the optimal decay rates of solutions by virtue of the frequency decomposition method. Specifically, for the low frequency part, we use the Fourier splitting method of Schonbek and the spectrum analysis method, and for the high frequency part, we use the global energy estimate and the behavior of exponentially decay operator.

关键词： tropical climate model large-time behavior global well-posedness

Chemical Measurement and Analysis: from Phenomenon to Essence

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Chinese Journal of Chemistry 2022年第16期40卷 1975-1986页

作者： Wei Zhao Jing-juan Xu State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210023 China Institute of Nanochemistry and Nanobiology School of Environmental and Chemical EngineeringShanghai UniversityShanghai 2004China

The review summaries our achievements in optical,electrochemical,as well as mass spectrometry analysis and imaging with high sensitivity,specificity,and spatiotemporal *** promoted the plasmonic imaging system,and developed ultra-sensitive plasmonic nanoprobes for the tracking of single molecules in single living cells,as well as plasmonic nanocatalysts for highly efficient energy *** addition,we contributed a lot in electrogenerated chemiluminescence(ECL)analysis and *** works including localized surface plasmon resonance(LSPR)enhanced ECL,ECL ratiometric detection,BPE based ECL system,multi-color ECL sensing as well as super-resolved ECL imaging have been initiated by our ***,we also dedicated in nanopipette based electrochemical analysis in single living cells,as well as ESI-MS analysis on short time scale.

关键词： Biosensors Plasmonic imaging Electrogenerated chemiluminescence Electrochemistry Mass spectrometry

Single-neuron neurodegeneration as a degenerative model for Parkinson’s disease

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Neural Regeneration Research 2024年第3期19卷 529-535页

作者： Sandro Huenchuguala juan Segura-Aguilar Escuela de Tecnología Médica Facultad de SaludUniversidad Santo TomásLos CarrerasOsornoChile Molecular&Clinical Pharmacology Instituto de Ciencias Biomedicas(ICBM)Faculty of medicineUniversity of ChileIndependenciaSantiagoChile

The positive effect of levodopa in the treatment of Parkinson’s disease,although it is limited in time and has severe side effects,has encouraged the scientific community to look for new drugs that can stop the neurodegenerative process or even regenerate the neuromelanin-containing dopaminergic nigrostriatal *** preclinical studies with coenzyme Q10,mitoquinone,isradipine,nilotinib,TCH346,neurturin,zonisamide,deferiprone,prasinezumab,and cinpanemab prompted clinical ***,these failed and after more than 50 years levodopa continues to be the key drug in the treatment of the disease,despite its severe side effects after 4–6 years of chronic *** lack of translated successful results obtained in preclinical investigations based on the use of neurotoxins that do not exist in the human body as new drugs for Parkinson’s disease treatment is a big *** our opinion,the cause of these failures lies in the experimental animal models involving neurotoxins that do not exist in the human body,such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and 6-hydroxydopamine,that induce a very fast,massive and expansive neurodegenerative process,which contrasts with the extremely slow one of neuromelanin-containing dopaminergic *** exceedingly slow progress of the neurodegenerative process of the nigrostriatal neurons in idiopathic Parkinson’s patients is due to(i)a degenerative model in which the neurotoxic effect of an endogenous neurotoxin affects a single neuron,(ii)a neurotoxic event that is not expansive and(iii)the fact that the neurotoxin that triggers the neurodegenerative process is produced inside the neuromelanin-containing dopaminergic *** endogenous neurotoxin that fits this degenerative model involving one single neuron at a time is aminochrome,since it(i)is generated within neuromelanin-containing dopaminergic neurons,(ii)does not cause an expansive neurotoxic effect and(iii)triggers all the mechanisms involved in t

关键词： 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine 6-hydroxydopamine aminochrome dopaminergic neurons DT-diaphorase exogenous neurotoxins glutathione transferase M2-2

Near-field time-frequency localization method using sparse representation

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The Journal of China Universities of Posts and Telecommunications 2012年第6期19卷 29-34页

作者： WANG Bo LIU juan-juan SUN Xiao-ying ZHANG Yan-jun College of Communication Engineering Jilin University

This paper presents a novel near-field source localization method based on the time-frequency sparse model. Firstly, the method converts the time domain data of array output into time-frequency domain by time-frequency transform; then constructs sparse localization model by utilizing the specially selected time-frequency points, and finally the greedy algorithms are chosen to solve the sparse problem to localize the source. When the coherent sources exist, we propose an additional iterative selection procedure to improve the estimation performance. The proposed method is suitable for uncorrelated and coherent sources, moreover, the improved estimation accuracy and the robustness to low signal to noise ratio （SNR） are achieved. Simulations results verify the efficiency of the proposed algorithm

关键词： near-field source time-fi'equency distribution sparse representation DOA estimation range estimation greedy algorithm

A Mn-porphyrinic metal–organic framework immobilizing glucose oxidase for combined photodynamic/chemodynamic/starvation therapy

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Tungsten 2025年第1期 183-194页

作者： Xin-Ran Sun Hao-Ming Yuan Guo-Da Zhang Chao Wang Shu-juan Sun Peng-Fei Shi Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers School of Chemistry and Chemical Engineering Linyi University

The combination of photodynamic therapy（PDT） and chemodynamic therapy（CDT） in tumor treatment has attracted considerable ***,tumor hypoxia and glutathione（GSH） overproduction in the tumor tissue restricted the progress of their ***,a Mn-porphyrinic metal-organic framework（Mn-TCPP） was constructed by the one-pot method and further used for immobilizing glucose oxidase（GOx） to obtain GOx@*** would rapidly exhaust endogenous glucose into hydrogen peroxide（H2O2） and gluconic acid,thus shutting off the energy supply of tumor cells for starvation ***-TCPP catalyzed H2O2to produce oxygen,regulating the hypoxic tumor microenvironment and in turn improving1O2generation under laser ***,Mn-TCPP can reduce reactive oxygen species consumption owing to the redox reaction between Mn3+and GSH,thus greatly enhancing ***,benefiting from GOx-mediated starvation therapy,Mn2+produced by Mn3+reduction can react with sufficient intracellular H2O2to generate ·OH with high cytotoxicity through a Fenton-like *** treatment by GOx@Mn-TCPP under laser irradiation in vitro,the cell viability of 4T1 and A549 tumor cells reached to 20%,reflecting GOx@Mn-TCPP could give full play to the advantages of PDT/CDT/starvation *** results in vivo demonstrated that GOx@Mn-TCPP mediated synergistic cascade therapy could significantly inhibit tumor growth and improve the therapeutic effect.

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