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Frontiers of Education in China 2022年第3期17卷 361-387页

作者： SUN Ran DU Ping YANG Jing Faculty of Education Beijing Normal UniversityBeijing 100875China

The Special-Contracted Teacher Scheme,a supplement to the traditional mode of teacher supply,has been implemented for 17 years and the teaching quality of those teachers has gained a lot of *** data of teachers and students from the sample counties in four central and western provincial-level administrative units,this paper studies how special-contracted teachers have affected students’academic performance and non-cognitive ability according to the student development framework of the new human capital theory,and how those effects vary among different teacher *** show that while special-contracted teachers have helped improve the academic performance of rural students,their role is limited in improving students’non-cognitive *** the same time,female special-contracted teachers and those without a normal major play an obviously bigger role in raising students’academic *** conclusion is that special-contracted teachers can to some extent help narrow the urban-rural gap in academic performance,but more research needs to be done to better understand their effects on students’non-cognitive ability.

关键词： special-contracted teachers students’development new human capital theory evaluation of teacher quality educational equality

Homozygosity for the CD1E★02 allele is associated with a resistance to Plasmodium falciparum malaria infection in Gabonese school children

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Asian Pacific Journal of Tropical Medicine 2017年第2期10卷 195-198页

作者： Landry-Erik Mombo Francine Ntoumi Cyrille Bisseye Rajendranath Ramasawmy Pascal Millet Ryad Tamouza Centre International de Recherches Medicales de Franceville(CIRMF) BP 769FrancevilleGabon INSERM U458 Hopital Robert Debre48 Bd Serurier75019 ParisFrance Laboratoire d'Immunologie et d'Histocompatibilite AP-HP IUH and INSERM U662Hopital Saint-LouisParisFrance

Objective:To explore the possible association between polymorphisms in CD1 genes and both asymptomatic and mild Plasmodium falciparum ***:Two clusters of 85 school children,from the village of Dienga(Gabon) were *** first group was analysed for the prevalence and the multiplicity of asymptomatic Plasmodium falciparum infection,whereas the second group was screened for the frequency of malarial ***:Our findings showed that homozygosity for the CD1E★02 allele was associated with a low frequency of malarial ***,a strong association between CD1E★02 homozygotes and the resistance to multiple malarial attacks was *** CD1A★01 allele showed a weak association with a small number of malarial ***:Our results suggest a possible role of CD1E polymorphisms in malaria protection among school children and that CD1e molecules are involved in anti-malarial immunity.

关键词： CD1E CD1A Malaria GPI Gabon

Influence of temperature cycling and pore fluid on tensile strength of chalk

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第2期11卷 277-288页

作者： T.Voake A.Nermoen C.Ravn?s R.I.Korsnes I.L.Fabricius University of Stavanger The National IOR Center of Norway University of Stavanger NORCE Norwegian Research Centre AS Technical University of Denmark

Calcite has a highly anisotropic thermal expansion coefficient, and repeated heating and cooling cycles can potentially destabilize chalks by breaking cement bonds between neighboring particles. Based on tensile strength measurements, we investigated how temperature cycles induce weakening of *** strength tests were performed on chalk specimens sampled from Kansas(USA) and Mons(Belgium), each with differing amounts of contact cement. Samples of the two chalk types were tested in dry and water-saturated states, and then exposed to 0, 15, and 30 temperature cycles in order to find out under what circumstances thermally induced tensile strength reduction occurs. The testing results show that the dry samples were not influenced by temperature cycling in either of the chalk types. However, in the water-saturated state, tensile strength is increasingly reduced with progressive numbers of temperature cycles for both chalk samples, especially for the more cemented Kansas chalk. The Kansas chalk demonstrated higher initial tensile strength compared to the less cemented Mons chalk, but the strength of both chalks was reduced by the same relative proportion when undergoing thermal cycles in the water-saturated state.

关键词： Tensile strength Weakening by heating and cooling cycles Anisotropic thermal expansion

Nankai Trough Velocity Structure Reconstruction using FWI of Wide-angle OBS Data with Graph-space Optimal Transport Misfit Function

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Acta Geologica Sinica(English Edition) 2021年第S01期95卷 11-14页

作者： Andrzej GóRSZCZYK Romain BROSSIER Ludovic MéTIVIER ISTerre Université Grenoble AlpesGrenobleFrance Institute of Geophysics Polish Academy of SciencesWarsawPoland Université Grenoble Alpes CNRSLJKGrenobleFrance

Technical development oriented on the detailed seismic imaging and velocity model building coupled with rapid increase of the computing power available nowadays make it possible to process large volumes of seismic dat... 详细信息

关键词： time-domain full-waveform inversion alternative misfit function high-resolution crustal-scale imaging

An Advanced Analysis of Cloud Computing Concepts Based on the Computer Science Ontology

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Computers, Materials & Continua 2021年第3期66卷 2425-2443页

作者： PawełLula Octavian Dospinescu Daniel Homocianu Napoleon-Alexandru Sireteanu Krakow University of Economics KrakowPoland Alexandru Ioan Cuza University Iasi700706Romania

Our primary research hypothesis stands on a simple idea:The evolution of top-rated publications on a particular theme depends heavily on the progress and maturity of related *** this even when there are no clear relations or some concepts appear to cease to exist and leave place for newer ones starting many years *** implemented our model based on Computer Science Ontology(CSO)and analyzed 44 years of *** we derived the most important concepts related to Cloud Computing(CC)from the scientific collection offered by Clarivate *** methodology includes data extraction using advanced web crawling techniques,data preparation,statistical data analysis,and graphical *** obtained related concepts after aggregating the scores using the Jaccard coefficient and CSO *** article reveals the contribution of Cloud Computing topics in research papers in leading scientific journals and the relationships between the field of Cloud Computing and the interdependent subdivisions identified in the broader framework of Computer Science.

关键词： Cloud computing scientific literature cloud related concepts CSO ontology

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灰漠土土壤全氮含量的高光谱特征分析及估测

新疆农业科学 2017年第1期54卷 140-147页

作者：刘凡马玲杨光陈建华马雪莲王海江石河子大学农业资源与环境系新疆石河子832000

【目的】研究传统土壤全氮含量测定方法,解决复杂、耗时、耗力等问题。【方法】以新疆干旱区灰漠土为研究对象,运用经典统计学和光谱学相结合的方法,研究灰漠土土壤全氮含量的光谱反射特性,通过对原始光谱的数据变换和相关性分析,构建... 详细信息

【目的】研究传统土壤全氮含量测定方法,解决复杂、耗时、耗力等问题。【方法】以新疆干旱区灰漠土为研究对象,运用经典统计学和光谱学相结合的方法,研究灰漠土土壤全氮含量的光谱反射特性,通过对原始光谱的数据变换和相关性分析,构建了土壤全氮含量的高光谱估测模型,并对模型进行对比和验证。【结果】土壤中全氮含量不同光谱反射特性趋势相近,土壤的光谱反射率在780、1 800和2 140 nm波长附近出现波峰,在1 910 nm附近有明显的波谷,土壤全氮含量与原始光谱反射率相关性较差。通过一阶微分处理后的光谱数据与全氮含量的相关性显著优于原始光谱和二阶微分处理,最大相关系数为0.819,达到极显著相关;利用一阶微分变换从中提取特征波段667和1 414 nm,建立土壤全氮含量的估测模型:Y=2 698.048 X667-1062.149 X1414-0.015,R2为0.75,对估测模型进行验证发现,R2为0.80,当全氮含量过大或过小时,模型估测偏差相对较大,总体预测精度较高。【结论】高光谱分析技术对土壤全氮含量的预测具有一定的意义,利用估测模型可以快速鉴定土壤全氮含量。

关键词：灰漠土土壤全氮含量光谱反射特性高光谱估测模型

Spontaneous twisting of a collapsed carbon nanotube

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Nano Research 2017年第6期10卷 1942-1949页

作者： Hamid Reza Barzegar Aiming Yan Sinisa Coh Eduardo Gracia-Espino Claudia Ojeda-Aristizabal Gabriel Dunn Marvin L. Cohen Steven G. Louie Thomas Wagberg Alex Zettl Department of Physics University of California Berkeley CA 94720 USA Department of Physics Umea University 90187 Umea Sweden Materials Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Kavli Energy NanoSciences Institute at the University of California Berkeley and the Lawrence Berkeley National Laboratory Berkeley CA 94720 USA

We study the collapsing and subsequent spontaneous twisting of a carbon nanotube by in situ transmission electron microscopy （TEM）. A custom-sized nanotube is first created in the microscope by selectively extracting shells from a parent multi-walled tube. The few-walled, large-diameter daughter nanotube is driven to collapse via mechanical stimulation, after which the ribbon-like collapsed tube spontaneously twists along its long axis. In situ diffraction experiments fully characterize the uncollapsed and collapsed tubes. The experimental observations and associated theoretical analysis indicate that the origin of the twisting is compressive strain.

关键词： multi-walled carbonnanotube collapsed carbon nanotube in situ TEM electron diffraction twisting graphene nanoribbons

Role of the porphyrins and demulsifiers in the aggregation process of asphaltenes at water/oil interfaces under desalting conditions:a molecular dynamics study

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Petroleum Science 2020年第3期17卷 797-810页

作者： H.Santos Silva A.Alfarra G.Vallverdu D.Bégué B.Bouyssiere I.Baraille Institut des Science Analytiques et Physico-Chimie pour l’Environnement et les Materiaux UMR 5254CNRS/Univ Pau&Pays Adour64000 PauFrance total Research and Technology GonfrevilleBP 2776700 HarfleurFrance Joint Laboratory C2MC:Complex Matrices Molecular Characterization Total Research and TechnologyGonfrevilleBP 2776700 HarfleurFrance

Breaking water-in-oil emulsions during the refining of crude oils is an important step before any upgrading process is *** molecules are incriminated as playing an important role in this *** the mechanisms behind the affinity between them and water is a key step to understand how to break these emulsions more easily and require lower amounts of *** which demulsifier molecule(s)to use is also primordial,but to do so rationally,one needs to know which are the molecular interactions in place between asphaltenes,porphyrins and water so that demulsifiers are chosen to destabilize a specific physical–chemical *** this paper,we study the interactions arising between asphaltenes and porphyrins and six different molecules potentially displaying a demulsification action in the presence of water/oil *** demonstrate that the ionic demulsifier molecules present an interesting potential to either interact strongly with water,replacing asphaltenes in this interaction,or to interact with the active sites of asphaltenes,deactivating them and avoiding any asphaltenic interfacial ***,we also found that although asphaltenes do not migrate spontaneously toward the water/oil interfaces,porphyrins do so rather *** indicates that porphyrins do have an important activity at the water/oil interface.

关键词： Asphaltenes aggregation Petroporphyrins Molecular dynamics Emulsion Water-oil interface Demulsifiers

Analysis of and Theoretical Reflections on China's "Excessive De-Industrialization" Phenomenon

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Chinese Journal of Urban and Environmental Studies 2019年第4期7卷 58-88页

作者： WEI Houkai WANG Songji Rural Development Institute Chinese Academy of Social Sciences

Industrialization is a long-term process of spiral transformation and *** a broad sense,industrialization can be divided into two stages,*** industrialization and deep *** first stage refers to a process of expansive industrialization aiming to increase the proportion of industry,while the second stage refers to a process of contractive industrialization centered on improvements in industrial quality and competitiveness,to which the shallow industrialization is transformed and *** fact,the industrialization stages divided according to traditional theories,*** stage,middle stage and late stage,are only for achieving the goals of shallow industrialization,instead of ultimately completing the developmental tasks of industrial *** transforming and upgrading from shallow industrialization to deep industrialization is an essential stage for a major country to enhance its development quality and competitiveness of industrial *** far,China has not fully *** the context of unbalanced and inadequate industrial development,China has seen a rapid decline in the industrial value-added and employment proportions in recent years,prematurely showing the features of rapid excessive de-industrialization in all ***'s current excessive de-industrialization is not only attributed to the impulse of rushing into mass actions in industrial upgrading,but also resulting from the combined effects of multiple factors such as surging factor prices and overcapacity at the current stage,exerting serious negative impacts on China's economic growth,productivity improvement,development of modem service industry and transfer of agricultural labor *** a long period of time ahead,considering the need to improve the quality of industrialization and the relationship between industry and services,real economy and virtual economy,the industry dominated by advanced manufacturing industry is still China's major impe

关键词： De-industrialization advanced manufacturing modern service industry deep industrialization industrialization stages

Combined effects of p53 and MDM2 polymorphisms on susceptibility and surgical prognosis in hepatitis B virus-related hepatocellular carcinoma

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Protein & Cell 2013年第1期4卷 71-81页

作者： Yun Yang Tian Xia Ning Li Jin Zhang Yuan Yang Wenming Cong Qiang Deng Ke Lan Weiping Zhou The Third Department of Hepatic Surgery Eastern Hepatobiliary Surgery HospitalSecond Military Medical UniversityShanghai 200433China Key Laboratory of Molecular Virology and Immunology Institute Pasteur of ShanghaiChinese Academy of SciencesShanghai 200025China Department of Infectious Diseases Huashan HospitalFudan UniversityShanghai 200040China Department of Pathology Eastern Hepatobiliary Surgery HospitalSecond Military Medical UniversityShanghai 200433China

The p53 signaling pathway works as a potent barrier to tumor *** single nucleotide polymor-phisms(SNPs)in the gene loci of p53 pathway,p53 codon 72 Arg72Pro and MDM2 SNP309(T>G),have been shown to cause perturbation of p53 function,but the effect of the two SNPs on the risk of hepatocellular carcinoma(HCC)remains *** study in-vestigated the influence of combined p53 Arg72Pro and MDM2 SNP309 on the risk of developing HCC in pa-tients with chronic hepatitis B virus infection,and evaluated the significance of the two combined SNPs on patient *** total,350 HCC patients,230 non-HCC patients,and 96 healthy controls were geno-typed for the p53 Arg72Pro and MDM2 *** combined p53 Pro/Pro and MDM2 G/G genotype was significantly associated with HCC risk(P=0.047).Mul-tivariate analysis indicated that combined p53 Pro/Pro and MDM2 G/G genotype was an independent factor affecting recurrence and survival(P<0.05).Patients with combined p53 Pro/Pro and MDM2 G/G genotypes had a poorer prognosis than other genotypes,P<0.01 for both disease-free survival(DFS)and overall survival(OS).DFS and OS rates also differed significantly be-tween Barcelona Clinic Liver Cancer(BCLC)stage A patients with combined p53 Pro/Pro and MDM2 G/G and other genotypes(P<0.05).Thus,the combined p53 Pro/Pro and MDM2 G/G genotype is associated with increased risk of developing HCC and is an independ-ent adverse prognostic indicator in early stage HCC.

关键词： hepatocellular carcinoma p53 MDM2 single nucleotide polymorphisms prognosis