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Progress in Natural Science:Materials International 2008年第2期18卷 161-165页

作者： Chan-Su Ryu center for Asian Monsoon and Climate Environment research Chosun University Gwangju Republic of Korea

The zonal displacement of the western Pacific subtropical high remarkably influences the climate anomalies in China. In this paper,a new zonal index of the subtropical high is defined by modifying previous indices,and is used to investigate the relationship between the zonal displacement of the subtropical high and the dominant modes of 850-hPa circulations. It is found that the zonal displacement of the subtropical high is significantly correlated with the first two leading modes of circulations. In particular,the correlation coefficient between the index and the time series associated with the second mode is as high as 0.78 in 1958-2003 (46 years). Since the second mode is not associated with significant anomalies of sea surface temperatures,the above results imply the diffculty in seasonal forecasting of the zonal displacement of the subtropical high. In addition,the interannual variability in the zonal displacement of the subtropical high has been considerably enhanced since 1978,due to the effects of both dominant modes,especially the second mode. This is likely to account for the frequent occurrence of anomalous climate in China during the recent two decades.

关键词： Western Pacific subtropical high General circulation Dominant mode Interannual variability Interdecadal variation

The research of an improved partial parallel interference canceller for near-far resistance

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Journal of Harbin Institute of Technology(New Series) 2006年第3期13卷 267-271页

作者：王永建周廷显 research center on Communications Harbin Institute of Technology Harbin 150001 China

The decorrelating detector for direct-sequence code-division multiple access (DS-CDMA) can afford good data estimate because it does not need to know many parameters of the received signal. However, it shows great performance deprivation when the background noise is high. On the other hand, partial parallel interference canceller (PPIC) has the potential to combat the near-far problem and have much lower computation complexity. But its performance depends on the initial data estimate. An improved PPIC scheme is proposed in this paper to combat the near-far problem. It utilizes the advantages of the two detectors by combining them. The focus of this paper is on the BER performance and the near-far resistance capability of the proposed scheme. Computer simulations demonstrate that the proposed detector has good BER performance and near-far resistance capability.

关键词： PPIC decorrelating detector BER, near-far resistance

Deep learning for exploring ultra-thin ferroelectrics with highly improved sensitivity of piezoresponse force microscopy

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npj Computational Materials 2023年第1期9卷 2066-2073页

作者： Panithan Sriboriboon Huimin Qiao Owoong Kwon Rama K.Vasudevan Stephen Jesse Yunseok Kim School of Advanced Materials and Engineering Sungkyunkwan University(SKKU)SuwonRepublic of Korea research center for Advanced Materials Technology Core Research InstituteSuwonRepublic of Korea center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTNUSA

Hafnium oxide-based ferroelectrics have been extensively studied because of their existing ferroelectricity,even in ultra-thin film ***,studying the weak response from ultra-thin film requires improved measurement *** general,resonance-enhanced piezoresponse force microscopy(PFM)has been used to characterize ferroelectricity by fitting a simple harmonic oscillation model with the resonance ***,an iterative approach,such as traditional least squares(LS)fitting,is sensitive to noise and can result in the misunderstanding of weak *** this study,we developed the deep neural network(DNN)hybrid with deep denoising autoencoder(DDA)and principal component analysis(PCA)to extract resonance *** DDA/PCA-DNN improves the PFM sensitivity down to 0.3 pm,allowing measurement of weak piezoresponse with low excitation voltage in 10-nm-thick Hf_(0.5)Zr_(0.5)O_(2) thin *** hybrid approaches could provide more chances to explore the low piezoresponse of the ultra-thin ferroelectrics and could be applied to other microscopic techniques.

关键词： spectrum ferroelectric excitation

Preventing brain aging by the artificial enforcement of the unfolded protein response:future directions

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Neural Regeneration research 2024年第2期19卷 393-394页

作者： Felipe Cabral-Miranda Claudio Hetz Instituto de Ciências Biomédicas Universidade Federal do Rio de JaneiroRio de JaneiroBrazil center for Geroscience Brain Health and MetabolismSantiagoChile、Biomedical Neuroscience InstituteFaculty of MedicineUniversity of ChileSantiagoChile、Program of Cellular and Molecular BiologyInstitute of Biomedical SciencesFaculty of MedicineUniversity of ChileSantiagoChile、Buck Institute for Research on AgingNovatoCAUSA

As the life expectancy of the world’s population increases,age-related diseases are emerging as one of the greatest problems facing modern *** onset of dementia and neurodegenerative diseases is strictly dependent on aging as a major risk factor and has a profound impact on various aspects of the lives of individuals and their families.

关键词： diseases aging directions

3D Numerical Simulation of Non-isothermal Resin Transfer Molding Filling Process Using Unstructured Tetrahedron Mesh

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Journal of Shanghai Jiaotong university(Science) 2010年第6期15卷 684-689页

作者：施飞董湘怀 National Engineering research center of Die and Mold CAD Shanghai Jiaotong University

We present a numerical formulation for resin flow based on the concept of quasi-steady state situation at the flow front. To be fit for complicated product shapes,we use the four-node unstructured tetrahedron mesh based on which the numerical formulation of temperature and degree of cure is developed. The validity of our method is established in the case where ffexible meshes are used. The results show that the numerical procedure,tested on known data,provides numerically valid and reasonably accurate predictions.

关键词： 3D non-isothermal resin transfer molding (RTM) numerical simulation unstructured tetrahedron mesh

Epithelial Cells in 2D and 3D Cultures Exhibit Large Differences in Higher-order Genomic Interactions

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Genomics, Proteomics & Bioinformatics 2022年第1期20卷 101-109页

作者： Xin Liu Qiu Sun Qi Wang Chuansheng Hu Xuecheng Chen Hua Li Daniel M.Czajkowsky Zhifeng Shao State Key Laboratory for Oncogenes and Bio-ID center School of Biomedical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai center for Systems Biomedicine Shanghai Jiao Tong UniversityShanghai 200240China Translational Medical center for Stem Cell Therapy&Institute for Regenerative Medicine Shanghai East HospitalSchool of Life Science and TechnologyShanghai Key Laboratory of Signaling and Disease ResearchTongji UniversityShanghai 200092China

Recent studies have characterized the genomic structures of many eukaryotic cells,often focusing on their relation to gene ***,these studies have largely investigated cells grown in 2D cultures,although the transcriptomes of 3D-cultured cells are generally closer to their in vivo *** examine the effects of spatial constraints on chromosome conformation,we investigated the genomic architecture of mouse hepatocytes grown in 2D and 3D cultures using in situ *** results reveal significant differences in higher-order genomic interactions,notably in compartment identity and strength as well as in topologically associating domain(TAD)-TAD interactions,but only minor differences are found at the TAD *** RNA-seq analysis reveals up-regulated expression of genes involved in physiological hepatocyte functions in the 3D-cultured *** genes are associated with a subset of structural changes,suggesting that differences in genomic structure are critically important for transcriptional ***,there are also many structural differences that are not directly associated with changes in gene expression,whose cause remains to be ***,our results indicate that growth in 3D significantly alters higher-order genomic interactions,which may be consequential for a subset of genes that are important for the physiological functioning of the cell.

关键词： 3D culture In situ Hi-C Chromosome conformation Compartment TAD

GENERATION MECHANISM OF MAGNETIC NOISE BURSTS IN THE EARTH’S MAGNETOTAIL

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Science China Mathematics 1991年第12期34卷 1492-1499页

作者：周国成曹晋滨 center for Space Science and Applied research Academia Sinica Beijing 100080 PRC

In this paper, we study the electromagnetic instability driven by ion beams and plasmainhomogeneity in the plasma sheet boundary layer and for the first time obtain the growthrate spectrum of electromagnetic waves in a broad frequency range (Ω_i<<0.1ω_(LH)?|ω_r|≤Ω_e,Ω_i and Ω_e are respectively the ion and electron cyclotron frequencies, ω_(LH)=(Ω_iΩ_e)^(1/2) is thelower hybrid frequency). The peak of the growth rate spectrum is near |ω_r|≈ω_(LH) and thesecond peak is near |ω_r|?Ω_e. The fundamental characteristics of the growth rate spectrumare in agreement with the satellite observations of the magnetic noise bursts in the magneto-tail.

关键词： Earth’s magnetotail magnetic noise bursts (MNB) ion beam plasma inhomogeneity electromagnetic instability.

Frist-principles prediction of elastic, electronic,and thermodynamic properties of high entropy carbide ceramic (TiZrNbTa)C

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Rare Metals 2022年第3期41卷 1002-1014页

作者： Kai Xiong Bao-Wen Wang Ze-Peng Sun Wei Li Cheng-Chen Jin Shun-Meng Zhang Si-Yong Xu Lei Guo Yong Mao National center for International research on Photoelectric and Energy Materials School of Materials and EnergyMaterials Genome InstituteYunnan UniversityKunming 650091China Advanced Computing center Information Technology CenterYunnan UniversityKunming 650091China

High-entropy carbide ceramics (HECs) have drawn increasing attention as their excellent mechanical and thermal properties. In this work, the crystal stability,mechanical behavior, electronic and thermodynamic properties of (TiZrNbTa)C HEC are investigated by the first-principles calculations. Obtained results reveal that the disordered transition-metal (TM) atoms result in serious local lattice distortion within the crystal. The lattice distortion plays a key role for the structural stabilization,mechanical anisotropy and thermodynamic behaviors of(TiZrNbTa)C. Increasing pressure leads to decrease the lattice parameter, volume and brittleness, meanwhile increase the elastic constants, elastic moduli, mechanical anisotropy, sound velocity, and Debye temperature. It is also discovered that charge delocalization occurs with the increase in pressure. The mechanical stability and anisotropy of (TiZrNbTa)C are attributed primarily to TM-C bonding.

关键词： High-entropy carbide ceramics Elastic constants Anisotropy Thermodynamic First-principles

Characteristics and Variations of the East Asian Monsoon System and Its Impacts on Climate Disasters in China

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Advances in Atmospheric Sciences 2007年第6期24卷 993-1023页

作者：黄荣辉陈际龙黄刚 center for Monsoon System research Institute of Atmospheric PhysicsChinese Academy of Sciences

Recent advances in studies of the structural characteristics and temporal-spatial variations of the East Asian monsoon （EAM） system and the impact of this system on severe climate disasters in China are reviewed. Previous studies have improved our understanding of the basic characteristics of horizontal and vertical structures and the annual cycle of the EAM system and the water vapor transports in the EAM region. Many studies have shown that the EAM system is a relatively independent subsystem of the Asian- Australian monsoon system, and that there exists an obvious quasi-biennial oscillation with a meridional tripole pattern distribution in the interannual variations of the EAM system. Further analyses of the basic physical processes, both internal and external, that influence the variability of the EAM system indicate that the EAM system may be viewed as an atmosphere-ocean-land coupled system, referred to the EAM climate system in this paper. Further, the paper discusses how the interaction and relationships among various components of this system can be described through the East Asia Pacific （EAP） teleconnection pattern and the teleconnection pattern of meridional upper-tropospheric wind anomalies along the westerly jet over East Asia. Such reasoning suggests that the occurrence of severe floods in the Yangtze and Hualhe River valleys and prolonged droughts in North China are linked, respectively~ to the background interannual and interdecadal variability of the EAM climate system. Besides, outstanding scientific issues related to the EAM system and its impact on climate disasters in China are also discussed.

关键词： East Asian monsoon system climate disaster persistent drought severe flood EAP pattern teleconnection

On the applicability of the single parabolic band model to advanced thermoelectric materials with complex band structures

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Journal of Materiomics 2021年第3期7卷 603-611页

作者： Johannes de Boor Institute of Materials research German Aerospace Center(DLR)51147KoelnGermany

Due to the complex interplay between composition,synthesis parameters and the performance of thermoelectric materials,the optimization of thermoelectric materials needs to be complemented by modelling.A relatively simple and thus popular approach is the so called single parabolic band model,which allows for an efficient optimization of the material properties and a benchmarking of different materials based on relatively few,well available experimental *** complex band structures are common for high performance materials,single parabolic band modelling is also employed with apparent success for material systems where the underlying assumptions are not well *** order to assess the validity of a single parabolic band analysis for such systems,the thermoelectric properties for two model systems are calculated:one with a single band that is twofold degenerate and one with a light and a heavy *** if the density of states masses and the scattering potentials are kept identical,the transport properties and in particular the Hall coefficients differ significantly,which leads to an incorrectly determined carrier *** the carrier concentration is the base for the single parabolic band analysis,all the quantities obtained from it(optimum carrier concentration,effective mass,deformation potential)are determined incorrectly as well.

关键词： Thermoelectrics Electrical transport Single parabolic band model