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Rare Metals 2024年第5期43卷 2093-2102页

作者： bo Peng Zi-Hao Zhou ping Xuan Jie Xu Lian-bo Ma School of Materials Science and Engineering Anhui University ofTechnologyMa'anshan 243002China Anhui Product Quality Supervision&Inspection Research Institute Hefei 230051China

Mn-based layered oxides are among the most promising cathode materials for sodium-ion batteries owing to the advantages of abundance,environmenta friendliness,low cost and high specific capacity.P2 and O'3 are two representative structures of Mn-based layered ***,the P2 structure containing insufficien Na generally exhibits low initial charge capacity,while O'3structure with sufficient Na delivers high initial charge capacity but poor cycle *** study prepared a multitude of Na_(x)MnO_(2)(x=0.7,0.8,0.9)cathode materials with varying P2/O'3 ratios and further investigated their electrochemical *** optimized Na_(0.8)MnO_(2) comprising 69.9 wt%O'3 and 30.1 wt%P2 phase,exhibited relatively balanced specific capacity,Coulombic efficiency and cycle ***,it achieved a high specific capacity of 128.9 mAh·g^(-1) with an initia Coulombic efficiency of 98.2%in half-cell configuration The Na_(0.8)MnO_(2)//hard carbon full cell also achieved a high specific capacity of 126.7 mAh·g^(-1) with an initia Coulombic efficiency of 98.9%.Moreover,the capacity fading mechanism was revealed by combining in-situ and ex-situ X-ray *** findings of this study provide theoretical guidance for further modification design of Mnbased layered cathodes.

关键词： Sodium-ion batteries Cathode materials Mn-based layered oxides P2/0'3 composites

Measure oriented training： a targeted approach to imbalanced classification problems

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Frontiers of Computer Science 2012年第5期6卷 489-497页

作者： bo YUAN Wenhuang liu Division of Informatics Graduate School at ShenzhenTsinghua UniversityShenzhen 518055China

Since the overall prediction error of a classifier on imbalanced problems can be potentially misleading and bi- ased, alternative performance measures such as G-mean and F-measure have been widely adopted. Various techniques in- cluding sampling and cost sensitive learning are often em- ployed to improve the performance of classifiers in such sit- uations. However, the training process of classifiers is still largely driven by traditional error based objective functions. As a result, there is clearly a gap between the measure accord- ing to which the classifier is evaluated and how the classifier is trained. This paper investigates the prospect of explicitly using the appropriate measure itself to search the hypothesis space to bridge this gap. In the case studies, a standard three- layer neural network is used as the classifier, which is evolved by genetic algorithms （GAs） with G-mean as the objective function. Experimental results on eight benchmark problems show that the proposed method can achieve consistently fa- vorable outcomes in comparison with a commonly used sam- pling technique. The effectiveness of multi-objective opti- mization in handling imbalanced problems is also demon- strated.

关键词： imbalanced datasets genetic algorithms (GAs),neural networks G-mean synthetic minority over-sampling technique (SMOTE)

Biomass Components and Environmental Controls in Ningxia Grasslands

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Journal of Integrative Agriculture 2012年第12期11卷 2079-2087页

作者： WANG Kai-bo LI Jian-ping SHANGGUAN Zhou-ping State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences School of Agriculture Ningxia University State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences

Grassland plays an important role in the global carbon cycle and climate regulation. However, there are still large uncertainties in grassland carbon pool and also its role in global carbon cycle due to the lack of measured grassland biomass at regional scale or global scale with a unified survey method, particular for below-ground biomass. The present study, based on a total of 44 grassland sampling plots with 220 quadrats across Ningxia, investigated the characteristics of above-ground biomass （AGB）, below-ground biomass （BGB）, litter biomass （LB）, total biomass （TB） and root：shoot ratios （R：S） for six predominantly grassland types, and their relationships with climatic factors. AGB, BGB, LB and TB varied markedly across different grassland types, the median value ranging from 28.2-692.6 g m-2 for AGB, 130.4-2 036.6 g m-： for BGB, 9.2-82.3 g m2 for LB, and 168.0-2 681.3 g m-： for TB. R：S showed less variation with median values from 3.2 to 5.3 （excluding marshy meadow）. The different grassland types showed similar patterns of biomass allocation, with more than 70% BGB for all types. There is evidence of strong positive effects associated with mean annual precipitation （MAP） and negative effects associated with mean annual temperature （MAT） on AGB, BGB, and LB, although both factors have the opposite effect on R：S.

关键词： grasslands above-ground biomass (AGB) below-ground biomass (BGB) root:shoot ratios (R:S) mean annual precipitation (MAP) mean annual temperature (MAT)

Zfyve16 regulates the proliferation of β-lymphoid cells

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Frontiers of Medicine 2018年第5期12卷 559-565页

作者： Xuemei Zhao Donghe Li Qingsong Qiu bo Jiao Ruihong Zhang ping liu Ruibao Ren State Key Laboratory for Medical Genomics Shanghai Institute of Hematology Collaborative Innovation Center of HematologyCollaborative Innovation Center of System Biology Ruo'in Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai200025 China Department of Biology Brandeis University Waltham MA 02454 USA

Zfyve16 (a.k.a. endofin or endosome-associated FYVE-domain protein), a member of the FYVE-domain protein family, is involved in endosomal trafficking and in TGF-β, BMP, and EGFR signaling. The FYVE protein SARA regulates the TGF-β signaling pathway by recruiting Smad2/3 and accelerating their phosphorylation, thereby altering their susceptibility to TGF-β-mediated T cell suppression. Zfyve16 binds to Smad4 and their binding affects the formation of Smad2/3-Smad4 complex in TGF-β signaling. However, the in vivo function of Zfyve16 remains unknown. In this study, we generated a Zfyve16 knockout mouse strain (Zfyve16KO) and examined its hematopoietic phenotypes and hematopoietic reconstruction ability. The proportion of Tcells in the peripheral blood of Zfyve16KO mice increases compared with that in wild-type mice. This finding is consistent with the role of Zfyve16 in facilitating TGF-β signaling. Unpredictably, B cell proliferation is inhibited in Zfyve16KO mice. The proliferation potential of Zfyve16KO B-lymphoid cells also significantly decreases in vitro. These results suggest that Zfyve16 inhibits the proliferation of T cells, possibly through the TGF-β signaling, but upregulates the proliferation of B-lymphoid cells.

关键词： TGF-β Zfyve16 endofin hematopoiesis lymphocytes

5-aza-2'-deoxycytidine in the regulation of antioxidant enzymes in retinal endothelial cells and rat diabetic retina

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International Journal of Ophthalmology(English edition) 2019年第1期12卷 1-7页

作者： Man-Yun Xie Yan Yang ping liu Yan Luo Shi-bo Tang Department of Ophthalmology the Second Xiangya HospitalCentral South University Hunan Clinical Research Center of Ophthalmic Diseas The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen University Aier School of Ophthalmology Central South University Aier Research Institute of Ophthalmology

AIM: To investigate the roles of a DNA methyltransferase(DNMT) inhibitor 5-aza-2'-deoxycytidine(5-aza-dC) in the regulation of antioxidant enzymes in diabetic retinopathy(DR) models. METHODS: DNMTs expressions and activity, and changes of two key antioxidant enzymes in DR, MnSOD(encoded by SOD2 gene) and glutathione S-transferase theta 1(GSTT1), were quantified in the isolated human retinal endothelial cells(HRECs) exposed to high glucose(HG) with or without 5-aza-dC treatment. The downstream exacerbating factors including vascular endothelial growth factor(VEGF), intercellular adhesion molecule 1(ICAM-1) and matrix metalloproteinase 2(MMP2), which are implicated in the pathogenesis of DR and closely related to oxidative stress were also analyzed. The key parameters were confirmed in the retina from streptozotocin(STZ) diabetic rats. RESULTS: DNMTs expression and DNMT activity was induced in HRECs exposed to HG. Hyperglycemia decreased MnSOD and GSTT1 expression. 5-aza-dC administration effectively suppressed DNMTs expression and activity and reversed the MnSOD and GSTT1 expression under HG condition. VEGF, ICAM-1 and MMP2 induced by HG were also suppressed by 5-aza-dC treatment. Similar results were observed in the retina from STZ diabetic rats. CONCLUSION: Our findings suggest that DNA methylation may serves as one of the mechanisms of antioxidant defense system disruption in DR progression. Modulation of DNA methylation using pharmaceutic means such as DNMT inhibitors could help maintain redox homeostasis and prevent further progression of DR.

关键词： DNA methylation diabetic model 5-aza-dC oxidative stress inflammation human retinal endothelial cells rat

Timing of convalescent plasma therapy-tips from curing a 100-yearold COVID-19 patient using convalescent plasma treatment: A case report

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World Journal of Clinical Cases 2021年第12期9卷 2890-2898页

作者： bo liu Kang-Kang Ren Nian Wang Xin-ping Xu Jue Wu Department of Laboratory Hospital No.967 of PLADalian 116000Liaoning ProvinceChina Department of Laboratory Guanggu Branch of Hubei Maternal and Child Health HospitalWuhan 430073Hubei ProvinceChina Gaoxin Hospital The First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina GrandOmics Diagnostics Co. LtdWuhan 430073Hubei ProvinceChina Translational Medicine Research Center Medical Innovation Research Division of Chinese PLA General HospitalBeijing 100853China

BACKGROUND Convalescent plasma therapy is used for the treatment of critically ill patients for newly discovered infectious diseases,such as coronavirus disease 2019(COVID-19)pneumonia,under the premise of lacking specific treatment drugs and corresponding *** the best timing application of plasma therapy and whether it is effective by antiviral and antibiotic treatment remain *** SUMMARY We describe a patient with COVID-19,a 100-year-old,high-risk,elderly male who had multiple underlying diseases such as stage 2 hypertension(very high-risk group)and infectious pneumonia accompanied by chronic obstructive pulmonary disease and *** mainly describe the diagnosis,clinical process,and treatment of the patient,including the processes of two plasma transfusion *** This provides a reference for choosing the best timing of convalescent plasma treatment and highlights the effectiveness of the clinical strategy of plasma treatment in the recovery period of patients with COVID-19 pneumonia.

关键词： COVID-19 Convalescent plasma therapy Treatment Elderly Timing Case report

Mechanism of oxygen releasing of copper ferrite in the formation of the corresponding oxygen-deficient compound

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Science China Chemistry 2009年第1期52卷 101-108页

作者： ZHANG ping YU bo ZHANG Lei Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 102201China

Copper ferrite is a promising material for hydrogen production through thermochemical water splitting. In this work, the cation distribution of copper ferrite and the corresponding oxygen-deficient compound of spinel structure was analyzed based on the crystal structural chemistry theory. The mechanism of oxygen releasing of CuO, Fe2O3, CuFe2O4 and metal (M=Ni, Mn or Zn) doped copper ferrite in the process of temperature rising was investigated by differential thermal analysis-thermogravimetry (DTA-TG). By combining the theoretical analysis with experimental results, the mechanism of oxygen releasing of copper ferrite is proposed, which is different from that of other ferrites. For copper ferrite, the oxygen releasing caused by Cu(II)→Cu(I) plays a predominant role, while for other ferrites, the oxygen releasing resulting from Fe(III)·Fe(II) is dominant.

关键词： copper ferrite oxygen deficient compound crystal structural chemistry theory DTA-TG oxygen releasing mechanism

Relationship Among Solutions of a Generalized Riccati Equation

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Communications in Theoretical Physics 2007年第4X期48卷 610-614页

作者： liu Xiao-ping liu Chun-ping Institute of Mathematics Yangzhou University Yangzhou 225002 China Gaoyou Branch Yangzhou Education College Gaoyou 225600 China

In this paper, some solutions of a generalized Riccati equation are investigated, which are given in the recent articles [Chaos, Solitons ＆ Fractals 24 （2005） 257; Phys. Lett. A 336 （2005） 463], and the relations... 详细信息

关键词： generalized Riccati equation nonlinear partial differential equations exact solution

2D hetero-structures based on transition metal dichalcogenides:fabrication,properties and applications

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Science Bulletin 2017年第16期62卷 1148-1161页

作者： ping liu Bin Xiang Department of Materials Science&Engineering CAS Key Lab of Materials for Energy Conversionand Synergetic Innovation Center of Quantum Information&Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China

Recently,two dimensional transition metal dichalcogenides MX_2(M = Mo,W,etc; X = S,Se,Te) have ignited immense interests because of their unique structural and physical properties for the potential applications in the nano-optoelectronics,valley-spintronics etc. In terms of the structural compatibility and van der Waals interaction,two dimensional(2D) MX_2 layers can be fabricated into various lateral and vertical hetero-structures. The atomically-thin hetero-structures comprising different layered MX_2 provide a new platform for exploring fundamental physics and device technologies with unprecedented phenomenon and extraordinary functionalities. In this review,we report the recent progress about the fabrication,properties and applications of 2D hetero-structures based on transition metal dichalcogenides.

关键词： Transition metal dichalcogenides Hetero-structures Chemical vapor deposition Charge transfer Optoelectronic devices

The Possible Mechanism of a Type of Vortex Heavy Rainfall during the Pre-Rainy Season in South China

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Atmospheric and Oceanic Science Letters 2011年第5期4卷 247-252页

作者： LI bo liu Li-ping ZHAO Si-Xiong State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

In this paper,NCEP reanalysis data,intensive observation data collected from field experiment,model simulation data,and topographic trial data are fully analyzed to study a severe heavy rainfall event during 5 6 June 2008 in South *** most warm region rainfall cases,this one is associated with an obvious vortex system,which draws in water vapor and energy from the southwest monsoon surges ahead of a low trough above the Bengal Bay (BLT,Bengal Low Trough).At the lower troposphere,three currents,especially the southwest current and the east current,converge into the southeast of the ***,the distributions of strong vorticity,water vapor,and ascending motion cause frequently occurrence and growth of convection *** possible reasons for this rainfall event are summarized as a conceptual model.

关键词： mechanism conceptual model vortex heavyrainfall South China