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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

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

Texture Feature Extraction from Thyroid MR Imaging Using High-Order Derived Mean CLBP

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Journal of Computer science & Technology 2019年第1期34卷 35-46页

作者： Zhe Liu Cheng-Jian Qiu Yu-Qing song Xiao-Hong Liu juan Wang Victor s.sheng school of Computer science and Telecommunication Jiangsu UniversityZhenjiang 212013China Department of Computer science University of Central ArkansasArkansas 72035U.S.A.

In the field of medical imaging,the traditional local binary pattern (LBP)and its improved algorithms are often sensitive to *** LBPs are solely based on the signal information from local differences,and the binary quantization method oversimplifies the local texture features while disregarding the imaging information from the concaveconvex regions between the high-order pixels and the neighboring sampling ***,we propose an improved Derived Mean Complete Local Binary Pattern (DM_CLBP) algorithm based on high-order *** the DM_CLBP method,the grey value of a single pixel is replaced by the mean grey value of the rectangular area block,and the difference between pixel values in the area is obtained using the second-order differentiation *** on the calculation concept of the complete local binary pattern (CLBP)algorithm,the cascade signs and magnitudes of the two components are encoded and recombined in DM_CLBP using a uniform *** results from the experiments showed that the proposed DM_CLBP descriptors achieved a classification accuracy of 94.4%.Compared with LBP and other improved algorithms,the DM_CLBP algorithm presented in this study can effectively differentiate between lesion areas and normal areas in thyroid MR,(magnetic resonance)images and shows the improved accuracy of area classification.

关键词： thyroid magnetic resonance imaging (MRI) local binary pattern texture feature complete local binary pattern (CLBP)

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

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

Optimal livelihood strategy for different poverty groups among farmers: a case study of the Qin-Ba Mountain area in south-shaanxi, China

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Journal of Mountain science 2020年第5期17卷 1206-1220页

作者： sU Fang YIN Ya-juan school of Economics and Management Shaanxi University of Science&TechnologyXi'an 710021China

Achieving sustainable livelihood is the ultimate goal of poverty alleviation efforts in mountainous areas,and selecting an optimal livelihood strategy for different poverty-type farmers greatly improves farmers’livelihood capital,resists livelihood risks,and promotes sustainable *** farmers,optimal livelihood strategy means better employment opportunities,higher family income(or better income structure),and stronger employability or development *** paper classifies different types of farmers’poverty on the basis of a quantitative evaluation of farmers’livelihood capital in the Qin-ba Mountain Area in south-shaanxi by using the k-means clustering method and subsequently the fuzzy evaluation method to evaluate the effectiveness of farmers’livelihood ***,the multi-attribute decision-making model is used to analyze the selection of optimal livelihood strategies for different poverty-type *** results suggest a significant difference in the selection of the optimal livelihood strategy for different poverty-type *** without financial and human capital choose to"go out to work,"farmers lacking natural capital choose to"acquire social insurance and government relief,"farmers without physical capital choose to"use loans,"and farmers lacking social capital choose to"use savings."studying the selection of optimal livelihood strategies for different poverty-type farmers can help to propose targeted sustainable livelihood optimization programs for farmers and accelerate efforts to overcome poverty in mountainous areas.

关键词： Optimal strategy Livelihood capital Effectiveness evaluation Qin-Ba Mountain Area shaanxi

supplemental smartamine M in higher-energy diets during the prepartal period improves hepatic biomarkers of health and oxidative status in Holstein cows

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Journal of Animal science and Biotechnology 2017年第3期8卷 624-635页

作者： Mario Vailati-Riboni Johan s.Osorio Erminio Trevisi Daniel Luchini juan J.Loor Mammalian Nutri Physio Genomics Department of Animal Sciences and Division of Nutritional SciencesUniversity of IllinoisUrbanaIL 61801USA Istituto di Zootecnica Facolt àdi scienze Agrarie Alimentari e AmbientaliUniversità Cattolica del Sacro Cuore29122 PiacenzaItaly Adisseo NA AlpharettaGA 30022USA. Dairy and Food science Department South Dakota State University1111 College Ave113H Alfred DairyScience HallBrookings SD 57007USA

Background： Feeding higher-energy prepartum is a common practice in the dairy industry. However, recent data underscore how it could reduce performance, deepen negative energy balance, and augment inflammation and oxidative stress in fresh cows. We tested the effectiveness of rumen-protected methionine in preventing the negative effect of feeding a higher-energy prepartum. Multiparous Holstein cows were fed a control lower-energy diet（CON, 1.24 Mcal/kg DM; high-straw） during the whole dry period（-50 d）, or were switched to a higher-energy（OVE, 1.54 Mcal/kg DM）, or OVE plus smartamine M（OVE ＋ sM; Adisseo NA） during the last 21 d before *** cows received the same lactation diet（1.75 Mcal/kg DM）. smartamine M was top-dressed on the OVE diet（0.07% of DM） from -21 through 30 d in milk（DIM）. Liver samples were obtained via percutaneous biopsy at -10, 7 and 21 DIM. Expression of genes associated with energy and lipid metabolism, hepatokines, methionine cycle, antioxidant capacity and inflammation was ***： Postpartal dry matter intake, milk yield, and energy-corrected milk were higher in CON and OVE ＋ sM compared with OVE. Furthermore, milk protein and fat percentages were greater in OVE ＋ sM compared with CON and OVE. Expression of the gluconeogenic gene PCK1 and the lipid-metabolism transcription regulator PPARA was again greater with CON and OVE ＋ sM compared with OVE. Expression of the lipoprotein synthesis enzyme MTTP was lower in OVE ＋ sM than CON or OVE. similarly, the hepatokine FGF21, which correlates with severity of negative energy balance, was increased postpartum only in OVE compared to the other two groups. These results indicate greater liver metabolism and functions to support a greater production in OVE ＋ sM. At 7 DIM, the enzyme GsR involved in the synthesis of glutathione tended to be upregulated in OVE than CON-fed cows, suggesting a greater antioxidant demand in overfed cows. Feeding OVE ＋ sM resulted in lower similar express

关键词： Energy Methionine Nutrigenomics Transition period