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Acta Metallurgica Sinica(English Letters) 2009年第2期22卷 117-122页

作者： Zhili ZHU Jinhua gu Yu jia Xing HU School of Physical Engineering and Material Physics Laboratory Zheng Zhou University Zhengzhou 450052 China

Using ab initio total energy calculations with the full-potential linearized augmented plane wave method, the possibilities of magnetism in one-dimensional In and Tl wires were explored and their properties as the function of geometric structures were studied. The results suggest that the linear In and Tl wires show magnetization at the equilibrium bond distance with magnetic moments of 0.71 and 0.67 μB/atom, respectively. Allowing ions to relax, the wires were deformed as zigzag structures, but no dimerization occurs. The zigzag wires also exhibit spontaneous magnetization, although the magnetic moments are lower than those of straight wires.

关键词： Magnetism Atomic wire First-principle-study

From atom to monatomic wire:an ab initio study of magnetism in 3d transition metals

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Acta Metallurgica Sinica(English Letters) 2010年第3期23卷 191-196页

作者： Zhili ZHU Jinhua gu Yu jia Xing HU School of Physical Engineering and Material Physics Laboratory Zheng Zhou University Zhengzhou 450052 China

A systematic ab initio study on magnetism of the 3d transition metals（TM） from atom to monoatomic wire within density functional theory with generalized gradient approximation（GGA） was *** results show that the spin coupling has strong intraatomic exchange strengths about 1 eV for isolated 3d TM *** magnetic moments are distinctly lower than those of free atoms for all dimers except Mn 2 .All the 3d TM elements exhibit magnetic ground states in the linear wire structure.

关键词： Ab initio study Magnetism Transition metals

Real-World COVID-19 Vaccine Protection Rates against Infection in the Delta and Omicron Eras

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Research 2023年第4期6卷 583-594页

作者： Yuru Zhu jia gu Yumou Qiu Song Xi Chen Center for Statistical Science Peking UniversityBeijingChina Department of Statistics Iowa State UniversityAmesIAUSA School of Mathematical Science and guanghua School of Management Peking UniversityBeijingChina Pazhou Lab GuangzhouChina

The real-world vaccine protection rates(VPRs)against the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection are critical in formulating future vaccination strategies against the *** on a varying coefficient stochastic epidemic model,we obtain 7 countries’real-world VPRs using daily epidemiological and vaccination data,and find that the VPRs improved with more vaccine *** average VPR of the full vaccination was 82%(SE:4%)and 61%(SE:3%)in the pre-Delta and Deltadominated periods,*** Omicron variant reduced the average VPR of the full vaccination to 39%(SE:2%).However,the booster dose restored the VPR to 63%(SE:1%)which was significantly above the 50%threshold in the Omicron-dominated *** analyses show that the existing vaccination strategies have significantly delayed and reduced the timing and the magnitude of the infection peaks,respectively,and doubling the existing booster coverage would lead to 29%fewer confirmed cases and 17%fewer deaths in the 7 countries compared to the outcomes at the existing booster taking *** call for higher full vaccine and booster coverage for all countries.

关键词： vaccine vaccination doses

Chinese scientific productivity ranking the fifth

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中华医学杂志(英文版) 2004年第1期 156-157页

作者： gu jia, CMJ

Comparing containment measures among nations by epidemiological effects of COVID-19

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National Science Review 2020年第12期7卷 1847-1851页

作者： jia gu Han Yan Yaxuan Huang Yuru Zhu Haoxuan Sun Yumou Qiu Songxi Chen Center for Statistical Science Peking University guanghua School of Management Peking University School of Mathematical Sciences Sichuan University Yuanpei College Peking University Center for Data Science Peking University Department of Statistics Iowa State University

The coronavirus disease 2019 (COVID-19) has evolved to a global pandemic since its inception in December *** have responded to the epidemics with different levels of responses and containment *** the unprecedented pressure on nations’healthcare systems and the deaths so far,there is an urgent need to evaluate the effects of the containment measures,which would be useful for countries to plan for their responses to counter the first or possibly the second wave of the epidemic.

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Discrepancy in fine root turnover estimates between diameter-based and branch-order-based approaches:a case study in two temperate tree species

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Journal of Forestry Research 2012年第4期23卷 575-581页

作者： SUN Jing-jue gu jia-cun WANG Zheng-quan School of Forestry Northeast Forestry UniversityHarbin 150040China

Fine root turnover plays a key role in carbon （C） budgets and nutrients cycles in forest ecosystems. However, the difference between branch-order-based and diameter-based approaches in estimating fine root turnover is still unclear. We studied root biomass turnover based on multiplying root standing biomass by turnover rate （inverse of median root longevity） in two Chinese temperate tree species, Fraxinus mand- shurica Rupr. and Larix gmelinii Rupr. The minirhizotron （MR） tech- nique was used to estimate longevities for first and second order roots, and total roots （R,o,al） apparent on the MR tube surface. The correspond- ing biomass for each root group was estimated by soil monolith. The difference in biomass turnover between Rtotal and the sum of the first and second order roots was used to represent the discrepancy between di- ameter- and order-based approaches. First order roots had shorter life spans and higher biomass turnover rates than the second order roots in both species. Biomass turnover estimated by the order-based method for F. mandshurica and L. gmelinii were 155.4 *** 158.9 g.m2.a-1, respectively, in comparison with 99.5 g.m^-2-a^-1 and 117.7 g.m^-2.a^-1 estimated by the diameter-based method, indicating that the diameter-based approach underestimated biomass turnover. The most probable reason was that the order-based method enhanced separation of the heterogeneous root population into relatively homogenous root groups with varying turnover rates. We conclude that separating fine root pool into different branch orders can improve the accuracy of estimates for fine root turnover, as well as the understanding of the belowground C allocation and nutrient cycling at ecosystem level.

关键词： Fraxinus mandshurica root life span root longevity Larix gmelinii minirhizotron soil monolith

Study on Vortex-Induced Motions of A New Type of Deep Draft Multi-Columns FDPSO

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China Ocean Engineering 2018年第1期32卷 1-13页

作者： gu jia-yang XIE Yu-lin ZHAO Yuan LI Wen-juan TAO Yan-wu HUANG Xiang-hong Marine Equipment and Technology Institute Jiangsu University of Science and Technology Zhenjiang 212003 China School of Naval Architecture and Marine Engineering Jiangsu University of Science and Technology Zhenjiang 212003China Marine Design & Research Institute of China Shanghai 200011 China

A numerical simulation and an experimental study on vortex-induced motion（VIM） of a new type of deep draft multi-columns floating drilling production, storage and offloading（FDPSO） are presented in this paper. The main dimension, the special variable cross-section column and the cabin arrangement of the octagonal pontoon are introduced based on the result. The numerical simulation is adapted to study the effects of current incidence angles and reduced velocities on this platform’s sway motion response. The 300 m water depth equivalent truncated mooring system is adopted for the model tests. The model tests are carried out to check the reliability of numerical simulation. The results consist of surge, sway and yaw motions, as well as motion trajectories. The maximum sway amplitudes for different types of offshore platform is also studied. The main results show that the peak frequencies of sway motion under different current incidence angles and reduced velocities vary around the natural frequency. The analysis result of flow field indicates that the change of distribution of vortex in vertical presents significant influences on the VIM of platform. The trend of sway amplitude ratio curve of this new type FDPSO differs from the other types of platform. Under 45° current incidence angle, the sway amplitude of this new type of FDPSO is much smaller than those of other types of offshore platform at 4.4 ≤ V;≤ 8.9. The typical ‘8’ shape trajectory does not appear in the platform’s motion trajectories.

关键词： FDPSO multi-columns vortex-induced motion(VIM) model tests variable cross-section column

Synergistic Effects of Glutamine Deprivation and Metformin in Acute Myeloid Leukemia

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Current Medical Science 2024年第4期44卷 799-808页

作者： Tong-yuan LIU Xing FU Ying YANG jia gu Min XIAO Deng-ju LI Department of Hematology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective The metabolic reprogramming of acute myeloid leukemia(AML)cells is a compensatory adaptation to meet energy requirements for rapid *** study aimed to examine the synergistic effects of glutamine deprivation and metformin exposure on AML *** SKM-1 cells(an AML cell line)were subjected to glutamine deprivation and/or treatment with metformin or bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl)ethyl sulfide(BPTES,a glutaminase inhibitor)or *** viability was detected by Cell Counting Kit-8(CCK-8)assay,and cell apoptosis and reactive oxygen species(ROS)by flow *** blotting was conducted to examine the levels of apoptotic proteins,including cleaved caspase-3 and poly(ADP-ribose)polymerase(PARP).Moreover,the human long noncoding RNA(lncRNA)microarray was used to analyze gene expression after glutamine deprivation,and results were confirmed with quantitative RT-PCR(qRT-PCR).The expression of metallothionein 2A(MT2A)was suppressed using *** growth and apoptosis were further detected by CCK-8 assay and flow cytometry,respectively,in cells with MT2A *** Glutamine deprivation or treatment with BPTES inhibited cell growth and induced apoptosis in SKM-1 *** lncRNA microarray result showed that the expression of MT family genes was significantly upregulated after glutamine ***2A knockdown increased apoptosis,while proliferation was not affected in SKM-1 *** addition,metformin inhibited cell growth and induced apoptosis in SKM-1 *** glutamine deprivation and metformin enhanced the sensitivity of SKM-1 cells to ***,the combination of glutamine deprivation with metformin exhibited synergistic antileukemia effects on SKM-1 *** Targeting glutamine metabolism in combination with metformin is a promising new therapeutic strategy for AML.

关键词： glutamine metformin acute myeloid leukemia metallothionein

NONLINEAR DYNAMICS RESPONSE OF CASING PIPE UNDER COMBINED WAVE-CURRENT

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Applied Mathematics and Mechanics(English Edition) 2005年第8期26卷 1040-1046页

作者： TANG You-gang（唐友刚） gu jia-yang（谷家扬） ZUO jian-li（左建立） MIN jian-qin（闵建琴） Department of Naval Architecture and Ocean Engineering School of Civil Engineering Tianjin University Tianiin 300072. P. R. China

The vortex-induced nonlinear vibration of casing pipes in the deep water was studied considering the loads of current and combined wave-current. The vortex-induced vibration equation of a casing pipe was set up considering the beam mode and Morison＇s nonlinear fluid loads as well as the vortex-excited loads. The approach of calculating vortex-excited nonlinear vibration by Galerkin＇s method was proposed. The natural vibration frequencies and modes were obtained, and the response including primary resonance induced by current and the composite resonance under combined wave-current for the 170 m long casing pipe in the 160 m depth of water were investigated. The results show that the dynamics response of casing pipe obviously increases, and the complicated response behaviors of casing pipe are described under combined wavecurrent.

关键词： casing pipes in the deep water fluid dynamics combined wave-current vortex-excited vibration composite resonance

Fast bowtie effect elimination for MODIS L1B data

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 120-126页

作者： REN Rui-zhi,guO Shu-xu,gu Ling-jia College of electronic science and engineering,Jilin University,Changchun 130012,China College of electronic science and engineering Jilin University Changchun 130012 China

The bowtie effect refers to geometry distortions for the moderate resolution imaging spectrum-radiometer （MODIS） level 1B （L1 B） data. Till now, to eliminate the bowtie effect, numerous methods are proposed. However, most of them have limitations in computation efficiency. Through a comparative study of existing methods, this article puts forward a fast method to eliminate the bowtie effect using the ephemeris data. In this method, the rough positions of overlapping data are first detected. Because of the influence caused by the instrarnent characters and the earth＇s curvature, the positions of overlapping data need to be rectified to obtain more precise results. The optimal rectification method used in this article is selected by comparing three methods. By using the optimal method, the rectified MODIS data can be obtained. The experiments demonstrate that the bowtie effect can be eliminated in less than 1 s. In contrast, other traditional methods spend at least 3 s, thus the proposed method is faster and more effective.

关键词： bowtie effect MODIS bilinear interpolation overlapping data rectification