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An automated method for glacial lake mapping in High Mountain Asia using Landsat 8 imagery

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Journal of Mountain Science 2018年第1期15卷 13-24页

作者： ZhanG mei-mei CHEN fang TIAN Bang-sen Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences No. 9 Dengzhuang South Road Beijing 100094 China University of Chinese Academy of Sciences Beijing 100049 China Hainan Key Laboratory of Earth Observation Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Sanya 572029 China

Glacial lakes in the High Mountain Asia(HMA)are sensitive to global warming and can result in much more severe flood disasters than some largesized *** accurate and robust method for the extraction of glacial lakes is critical to effective management of these natural water *** methods often have limitations in terms of low spectral contrast and heterogeneous backgrounds in an *** study presents a robust and automated method for the yearly mapping of glacial lake over a large scale,which took advantage of the complementarity between the modified normalized difference water index(MNDWI)and the nonlocal active contour model,required only local homogeneity in reflectance features of *** cloud computing approach with the Google Earth Engine(GEE)platform was used to process the intensive amount of Landsat 8 images from 2015 (344 path/rows and approximately 7504 scenes).The experimental results were validated by very high resolution images from Chinese GaoFen-1 (GF-1) panchromatic multi-spectral(PMS)and appeared a general good *** is the first time that information regarding the spatial distribution of glacial lakes over the HMA has been derived automatically within quite a short period of *** integrating it with the relevant indices,it can also be applied to detect other land cover types such as snow or vegetation with improved accuracy.

关键词： Glacial lake Landsat 8 Modified Normalized Difference Water Index Nonlocal active contour

Genetic basis and biotechnological manipulation of sexual dimorphism and sex determination in fish

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Science China(Life Sciences) 2015年第2期58卷 124-136页

作者： mei Jie GUI Jian-fang College of Fisheries Key Laboratory of Freshwater Animal Breeding Ministry of Agriculture Freshwater Aquaculture Collaborative Innovation Center of Hubei Province Huazhong Agricultural University State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of the Chinese Academy of Sciences

Aquaculture has made an enormous contribution to the world food production,especially to the sustainable supply of animal *** utility of diverse reproduction strategies in fish,such as the exploiting use of unisexual gynogenesis,has created a typical case of fish genetic breeding.A number of fish species show substantial sexual dimorphism that is closely linked to multiple economic traits including growth rate and body size,and the efficient development of sex-linked genetic markers and sex control biotechnologies has provided significant approaches to increase the production and value for commercial *** with the rapid development of genomics and molecular genetic techniques,the genetic basis of sexual dimorphism has been gradually deciphered,and great progress has been made in the mechanisms of fish sex determination and identification of sex-determining *** review summarizes the progress to provide some directive and objective thinking for further research in this field.

关键词： reproduction strategies sexual dimorphism sex determination sex-determining gene sex chromosome sex controlbreeding

Location Service Information Supporting System Based on Ontology

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Journal of Integrative Agriculture 2012年第5期11卷 858-864页

作者： HUANG Dong-mei fang Qian YU Qing-mei College of Information Shanghai Ocean UniversityShanghai 201306P.R.China

In order to solve the problem of how to collect and manage large amount of location information and improve the accuracy of location service, interactive information supporting system based on ontology and location service is presented in this paper. It can transmit special information about users＇ location to front-end instantaneously, so it is very convenient for their daily life. It makes full use of the available wireless communication, which is easy to arrange and convenient for users.

关键词： ontology location service location information supporting system

Poly(3-hexylthio) thiophene Field-effect Transistor Device Performance: Impact of the Content of Hexylthio Side Chain on Backbone

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Chinese Journal of Polymer Science 2024年第1期42卷 14-23,I0005页

作者： Hao-Yu Liu Lian-He han Ling-Wei Kong Li-Ping Zhu Xiao-Lan Qiao mei-fang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Regioregular poly(3-hexylthio)thiopene(P3HTT) has emerged tremendous potential in organic electronic applications due to the strong noncovalent interactions from the sulfur atom linked to thiophene. However, P3HTT generally exhibits low charge mobility mostly due to poor solution processability attributed to dense arrangement of hexylthio side chain in polymer, which led to strong noncovalent interactions among sulfur atoms. To balance the nonvalent interaction and aggregation for P3HTT, herein, we systematically study the effect of hexylthio side chain content in polymer backbone on the structure and properties. A series of regioregular P3HTT-based homopolymers(P3HTT, P3HTT-50,P3HTT-33 and P3HTT-25) were prepared via Kumada catalyst transfer polycondensation method from a set of mono-, bi-, ter-and quarterthiophenes containing different contents of hexylthio side chain. The DFT calculation shows the planarity of polymers backbone could be improved through reducing the density of hexylthio side chain in polymer mainchain. And significant changes in their crystallinity, aggregation and optical properties were observed with the content of hexylthio side chain reducing. The P3HTT-33 displayed the highest field-effect transistor hole mobility of 2.83×10^(-2) cm^(2)·V^(-1)·s^(-1) resulting from a balance between the crystallinity and planarity. This study demonstrates modulating the content of hexylthio side chain in P3HTT is an effective strategy to optimize the opto-electronic properties of polymer obtaining excellent semiconductor device performance.

关键词： Conjugated polymer Polythiophene Noncovalent interaction Molecular aggregation Organic field-effect transistor

Characterization and phylogenetic analysis of a phenanthrene-degrading strain isolated from oil-contaminated soil

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Journal of Environmental Sciences 2004年第4期16卷 589-593页

作者： XIAYing MINhang LUZhen-mei YEYang-fang CollegeofLifeScience ZhejiangUniversityHangzhou310029China

Bacterium strain EVA17 was isolated from an oil-contaminated soil, and identified as Sphingomonas sp. based on analysis of 16S rDNA sequence,cellular fatty acid composition and physiological-chemical tests. The salicylate hydroxylase and catechol 2,3-dioxygenase(C23O) were detected in cell-free lysates, suggesting a pathway for phenanthrene catabolism via salicylate and catechol. Alignment showed that both of the C23O and GST genes of the strain EVA17 had high similarity with homologues of strains from genus Sphingomonas. The phylogenetic analysis based on 16S rDNA and C23O gene sequence indicated that EVA17 should be classified into genus Sphingomonas, although the two phylogenetic trees were slightly different from each other. The results of co-amplification and sequence determination indicated that GST gene should be located upstream of the C23O gene.

关键词： phenanthrene 16S rDNA glutathione S-transferase catechol 2,3-dioxygenase phylogenetic analysis

Unveiling the role of Zn dopants in NiFe phosphide nanosheet for oxygen evolution reaction

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Progress in Natural Science:Materials International 2023年第1期33卷 74-82页

作者： Chendong Kou Jingrui han Haibin Wang mei han Hongyan Liang School of Materials Science and Engineering Tianjin University Key Laboratory of Efficient Utilization of Low and Medium Grade Energy Tianjin University

Transition metal phosphides have been recognized as promising electrocatalysts for oxygen evolution reaction(OER) due to their low cost and high activity. However, the insufficient exposed active region limited the OER performance. Recently, the introduction of sacrificial dopants has been considered an effective strategy to enlarge the surface area. Herein, the Zn dopants are introduced in NiFe phosphide(NiFeZnP) nanosheet, which work as the sacrificial dopants to generate more exposed active NiFe sites and promote the formation of the NiFeOOH active phase during OER process. The optimized Zn-doped NiFeP catalyst shows an overpotential of ≈203 mV to reach a current density of 10 mA cm-2in 1 M KOH, and a stability of 100 h at 1000 mA cm-2. Overall, this work provides a sacrificial Zn doping strategy to prepare highly efficient OER electrocatalysts.

关键词： Transition metal phosphide Sacrificial dopant Self-supported electrode Oxygen evolution reaction

Electroless Plating of Thin Silver Films on Porous Al_2O_3 Substrate and the Study of Deposition Kinetics

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Tsinghua Science and Technology 2005年第6期10卷 680-689页

作者： fang mei Donglu Shi Department of Chemical and Materials Engineering University of Cincinnati Cincinnati OH 45221-0012 USA

A novel concept has been developed to coat the inner pore surfaces of reticulated alumina with a thin silver film by an electroless-plating method. As a result of coating, the porous alumina sample exhibits a sharp transition from insulating to conducting due to a thin silver layer on the inner pore surfaces. Systematic studies have been carried out to investigate the coating kinetics by employment of scanning electron microscope （SEM）, X-ray diffraction （XRD）, and computer simulation. Both coating procedures and effects of processing parameters on the quality of films are reported. Also, this paper presents the film bonding strength to the substrate, effects of sintering, and conduction mechanism of coated composite. The fundamental silver electroless-plating mechanism has been identified based on computer modeling. The simulation results indicate an excellent agreement between the silver deposition behavior and the physical model applied.

关键词： electroless plating thin silver films deposition kinetics

Correlations between hippocampal functional connectivity,structural changes,and clinical data in patients with relapsing-remitting multiple sclerosis:a case-control study using multimodal magnetic resonance imaging

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Neural Regeneration Research 2022年第5期17卷 1115-1124页

作者： Xin-Quan Gu Ying Liu Jie-Bing Gu Lin-fang Li Ling-Ling Fu Xue-mei han China-Japan Union Hospital of Jilin University ChangchunJilin ProvinceChina First Department of Neurology China-Japan Union Hospital of Jilin UniversityChangchunJilin ProvinceChina Cardre’s Ward Changchun Central hospitalChangchunJilin ProvinceChina

Multiple sclerosis is associated with structural and functional brain alterations leading to cognitive impairments across multiple domains including attention,memory,and the speed of information *** hippocampus,which is a brain important structure involved in memory,undergoes microstructural changes in the early stage of multiple *** this study,we analyzed hippocampal function and structure in patients with relapsing-remitting multiple sclerosis and explored correlations between the functional connectivity of the hippocampus to the whole brain,changes in local brain function and microstructure,and cognitive function at *** retrospectively analyzed data from 20 relapsing-remitting multiple sclerosis patients admitted to the Department of Neurology at the China-Japan Union Hospital of Jilin University,China,from April 2015 to November *** healthy volunteers were recruited as the healthy control *** participants were evaluated using a scale of extended disability status and the Montreal cognitive assessment within 1 week before and after head diffusion tensor imaging and functional magnetic resonance *** with the healthy control group,the patients with relapsing-remitting multiple sclerosis had lower Montreal cognitive assessment scores and regions of simultaneously enhanced and attenuated whole-brain functional connectivity and local functional connectivity in the bilateral *** diffusion tensor imaging data showed that,compared with the healthy control group,patients with relapsing-remitting multiple sclerosis had lower hippocampal fractional anisotropy values and higher mean diffusivity values,suggesting abnormal hippocampal *** left hippocampus whole-brain functional connectivity was negatively correlated with the Montreal cognitive assessment score(r=-0.698,P=0.025),and whole-brain functional connectivity of the right hippocampus was negatively correlated with extended disability stat

关键词： cognitive impairment diffusion tensor imaging fractional anisotropy functional connectivity functional magnetic resonance imaging hippocampus local consistency low frequency oscillation amplitude mean diffusivity multiple sclerosis neurodegeneration

Functional microglia derived from human pluripotent stem cells empower retinal organs

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Science China(Life Sciences) 2022年第6期65卷 1057-1071页

作者： mei-Ling Gao Xiao Zhang fang han Jia Xu Si-Jian Yu Kangxin Jin Zi-Bing Jin Institute of Stem Cell Research The Eye HospitalWenzhou Medical UniversityWenzhou 325027China Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing Ophthalmology&Visual Sciences Key LaboratoryBeijing 100730China

Microglia are known to play essential roles in the development,progression and treatment of diverse neurodegenerative diseases in the central nervous system,including the retina,brain and spinal ***,brain-induced microglia-like cells(iMGs)have been generated from human pluripotent stem cells(hPSCs);however,retinal microglia have yet to be developed in *** this study,by mimicking in vivo microglial development,we established a simplified approach to differentiate hPSCs into high purity(>90%)*** iMGs express microglia-specific markers,release cytokines upon stimulation,and are capable of phagocytizing *** co-cultured with three-dimensional human retinal organoids(hROs),iMGs migrated into the hROs,tended to differentiate into resident retinal microglia,and simultaneously induced apoptosis in some neural ***,the resident i MGs in the hROs formed sparse web-like structures beneath the photoreceptor cell layer,resembling microglia's orientation in human *** conclusion,we developed a simplified and efficient method to generate microglia from human pluripotent stem cells,and we report the first derivation of retinaresident microglia in vitro,providing a new source of human retinal microglia for developmental and disease studies and regenerative therapeutics.

关键词： microglia retinal organoid pluripotent stem cells differentiation human induced reprogramming