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An Algebraic Multigrid Method for Nearly Incompressible Elasticity Problems in Two-Dimensions

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Advances in Applied Mathematics and Mechanics 2009年第1期1卷 69-88页

作者： Yingxiong Xiao shi Shu Hongmei zhang Yuan Ouyang Civil Engineering and Mechanics College Xiangtan UniversityXiangtan 411105People’s Republic of China School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105People’s Republic of China Department of Mathematics and Physics Hunan University of TechnologyZhuzhou 412008People’s Republic of China

In this paper,we discuss an algebraic multigrid(AMG)method for nearly incompressible elasticity problems in ***,a two-level method is proposed by analyzing the relationship between the linear finite element space and the quartic finite element *** choosing different smoothers,we obtain two types of two-level methods,namely TL-GS and *** theoretical analysis and numerical results show that the convergence rates of TL-GS and TL-BGS are independent of the mesh size and the Young’s modulus,and the convergence of the latter is greatly improved on the order *** the convergence of both methods still depends on the Poisson’s *** fix this,we obtain a coarse level matrix with less rigidity based on selective reduced integration(SRI)method and get some types of two-level methods by combining different *** the existing AMG method used as a solver on the first coarse level,an AMG method can be finally *** results show that the resulting AMG method has better efficiency for nearly incompressible elasticity problems.

关键词： Locking phenomenon algebraic multigrid higher-order finite element two-level method reduced integration

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活性炭吸附苯系物性能的研究进展

地球环境学报 2024年第1期15卷 44-58页

作者：张超锋李荣石先进黄宇中国科学院地球环境研究所黄土与第四纪地质国家重点实验室中国科学院气溶胶化学与物理重点实验室西安710061 中国科学院第四纪科学与全球变化卓越创新中心西安710061 中国科学院大学北京100049

人类活动排放的挥发性有机物(VOCs),尤其是苯系物(BTEX),不仅影响空气质量,还会对人体健康产生不同程度的危害。室内苯系物具有浓度低、释放周期长及来源复杂等特点。由于活性炭(AC)优异的孔道结构和易调控的表面化学性质,采用活性炭吸... 详细信息

人类活动排放的挥发性有机物(VOCs),尤其是苯系物(BTEX),不仅影响空气质量,还会对人体健康产生不同程度的危害。室内苯系物具有浓度低、释放周期长及来源复杂等特点。由于活性炭(AC)优异的孔道结构和易调控的表面化学性质,采用活性炭吸附苯系物是封闭/半封闭空间空气污染控制的最有效策略之一。本文综述了封闭/半封闭空间苯系物的理化特征、活性炭的物理化学性质及其吸附苯系物的影响因素。这些因素主要包括活性炭物理结构、表面化学性质、苯系物分子结构和吸附条件。此外,还进一步探讨了活性炭再生技术,并展望了针对封闭/半封闭空间苯系物污染的活性炭吸附技术的改进策略。

关键词：活性炭吸附苯系物表面物理化学性质再生技术

技术性贸易措施对上海出口贸易影响的实证分析

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标准科学 2024年第3期 57-62页

作者：石念戴宇欣张正敏上海市质量和标准化研究院

上海地区出口主要以工业产品为主,技术性贸易措施对上海产品出口贸易的影响日益受到重视。本文通过构建修正引力模型,在关注TBT数量对地区出口影响的假设上,研究上海主要出口目的地实施TBT措施对上海出口贸易的影响程度及规律。结论显示... 详细信息

上海地区出口主要以工业产品为主,技术性贸易措施对上海产品出口贸易的影响日益受到重视。本文通过构建修正引力模型,在关注TBT数量对地区出口影响的假设上,研究上海主要出口目的地实施TBT措施对上海出口贸易的影响程度及规律。结论显示:进口国(地区)TBT措施对上海出口贸易存在一定的抑制作用,且当期影响最大,考虑到影响的时滞性,上海出口贸易遭遇TBT负面影响随着时间缓慢衰减,且降幅不大,说明了TBT对出口的实际影响是复杂的,另外,发达国家发起TBT后3个月内的抑制程度最强。

关键词： TBT 引力模型出口贸易地区发达国家

Gene cloning and sequence analysis of the cold-adapted chaperones DnaK and DnaJ from deep-sea psychrotrophic bacterium Pseudoalteromonas sp. SM9913

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Acta Oceanologica Sinica 2007年第6期26卷 91-100页

作者： ZHAO Dianli CHEN Xiulan HE Hailun shi Mei zhang Yuzhong State Key Laboratory of Microbial Technology Marine Biotechnology Research Center Shandong University Jinan 250100 China

Pseudoalteromonas sp. SM9913 is a phychrotmphic bacterium isolated from the deep-sea sediment. The genes encoding chaperones DnaJ and DnaK of P. sp. SM9913 were cloned by normal PCR and TAIL - PCR （GenBank accession Nos DQ640312, DQ504163 ）. The chaperones DnaJ and DnaK from the strain SM9913 contain such conserved domains as those of many other bacteria, and show some cold-adapted characteristics in their structures when compared with those from psychro-, meso-and themophilic bacteria. It is indicated that chaperones DnaJ and DnaK of P. sp. SM9913 may be adapted to low temperature in deep-sea and function well in assisting folding, assembling and translocation of proteins at low temperature. This research lays a foundation for the further study on the cold-adapted mechanism of chaperones DnaJ and DnaK of cold-adapted microorganisms.

关键词： cold-adapted chaperone DnaJ DnaK deep-sea Pseudoalteromonas sp. SM9913 gene cloning sequence analysis

The pikas of China: a review of current research priorities and challenges for conservation

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Integrative Zoology 2023年第1期18卷 110-128页

作者： Joseph P.LAMBERT Xiaozheng zhang Kun shi Philip RIORDAN Wildlife Institute School of Nature ConservationBeijing Forestry UniversityBeijingChina Eco-Bridge Continental Haidian DistrictBeijingChina Marwell Wildlife WinchesterHampshireUK

Of the approximately 30 extant species of pika(Ochotona;Ochotonidae;Lagomorpha),at least 23 occur in *** these,8 are endemic,and 3 are classiﬁed as Endangered by the *** into most Chinese species is scarce,and there is much to learn about basic aspects of their *** reviewed the literature on the 23 Chinese Ochotona species,with the aim of highlighting knowledge gaps and biases in research ***ﬁcally,we identify(1)which pika species receive the most attention from researchers,(2)which topics are the most frequently studied,and(3)how well research satisﬁes conservation *** covered a total of 879 articles,most of which were written in English or *** 75%of all publications focused on the plateau pika Ochotona *** species were represented by 10 or fewer publications *** and endemic species were particularly poorly represented.204 papers treated pikas as a pest,while 13 studied conservation *** species were considered possible targets for pest control,including some poorly known *** make some recommendations on how research into Chinese Ochotona could be improved,including:(1)recognizing that the current species-level taxonomy may be an ineffective way to prioritize conservation research in Ochotona,(2)directing more research toward threatened and endemic species,subspecies,and populations,(3)researching the ecosystem engineering effects of pikas,(4)collecting basic data on natural history of the many understudied species,and(5)researching threats,including climate change and pest control campaigns.

关键词： conservation Lagomorpha Ochotona prioritization research allocation

Andrographolide sensitizes prostate cancer cells to TRAIL-induced apoptosis

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Asian Journal of Andrology 2018年第2期20卷 200-204页

作者： Ruo-Jing Wei Xin-shi zhang Da-Lin He Department of Urology The First Affiliated Hospital of Xi'an Jiaotong University Xi'an 710061 China

Tumor necrosis factor-related apoptosis-inducing ligand （TRAIL） is a promising agent for anticancer therapy. The identification of small molecules that can establish the sensitivity of prostate cancer （PCa） cells to TRAIL-induced apoptosis is crucial for the targeted treatment of PCa. PC3, DU145, JAC-1, TsuPrl, and LNCaP cells were treated with Andrographolide （Andro） and TRAIL, and the apoptosis was measured using the Annexin V/PI double staining method. Real time-polymerase chain reaction （PCR） and Western blot analysis were performed to measure the expression levels of target molecules. RNA interference technique was used to down-regulate the expression of the target protein. We established a nude mouse xenograft model of PCa, which was used to measure the caspase-3 activity in the tumor cells using flow cytometry. In this research study, our results demonstrated that Andro preferentially increased the sensitivity of PCa cells to TRAIL-induced apoptosis at subtoxic concentrations, and the regulation mechanism was related to the up-regulation of DR4. In addition, it also increased the p53 expression and led to the generation of reactive oxygen species （ROS） in the cells. Further research revealed that the DR4 inhibition, p53 expression, and ROS generation can significantly reduce the apoptosis induced by the combination of TRAIL and Andro in PCa cells. In conclusion, Andro increases the sensitivity of PCa cells to TRAIL-induced apoptosis through the generation of ROS and up-regulation of p53 and then promotes PCa cell apoptosis associated with the activation of DR4.

关键词： andrographolide DR4 p53 reactive oxygen species tumor necrosis factor-related apoptosis-inducing ligand

结核病患者外周血白细胞介素-8、信号传导和转录激活因子3表达差异及其辅助诊断价值

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中国热带医学 2024年第4期24卷 411-416页

作者：安红娟李昆张灵霞朱琰李改平史阅韩孙卫国解放军总医院第八医学中心结核病诊疗新技术北京市重点实验室北京100091

目的探索耐多药结核病患者(multi-drug resistant tuberculosis,MDR-TB)、药物敏感结核病患者(drug susceptible tuberculosis,DSP-TB)及健康人3组人群外周血白细胞介素-8(interleukin-8,IL-8)、信号传导和转录激活因子3(signal transducer and activator of transcription 3,STAT3)表达差异,为开展新型结核病实验室辅助诊断提供参考依据。方法对3组人群外周血单个核细胞(peripheral blood mononuclear cell,PBMC)mRNA芯片表达谱差异性进行分析;选取MDR-TB患者与DSP-TB患者为研究对象,以健康人为对照组,酶联免疫吸附实验(enzyme linked immunosorbent assay,ELISA)测定各组血清IL-8浓度,比较组间差异;同时分离3组人群PBMC,收集细胞并提取总RNA,分别通过实时荧光定量PCR(quantitative real-time PCR,qPCR)技术分析各组IL-8、STAT3 mRNA表达情况;以蛋白免疫印迹(Western Blot)实验比较各组STAT3蛋白表达差异。结果MDR-TB和DSP-TB 2组人群血清IL-8浓度明显高于健康对照组,差异有统计学意义(P<0.05);MDR-TB组和DSP-TB组人群外周血PBMC中IL-8基因mRNA的相对表达量明显高于健康对照组,差异有统计学意义(P<0.05);qPCR与Western Blot实验结果均显示,健康组、DSP-TB组和MDR-TB组STAT3基因表达依次上调,组间差异有有统计学意义(P<0.05),实验所得结果与mRNA芯片结果一致。结论IL-8在活动性结核病(active tuberculosis,ATB)患者体内表达显著升高,可以作为标志物区分ATB与健康人群;STAT3浓度的变化不仅作为ATB的诊断参考,还可以鉴别DSP-TB与MDR-TB人群。IL-8、STAT3联合检测有望成为不同结核病患者的临床辅助诊断依据。

关键词：结核分枝杆菌活动性结核病白细胞介素-8 信号传导和转录激活因子3

Cis-regulatory change and expression divergence between duplicate genes formed by genome duplication of Arabidopsis thaliana

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Chinese Science Bulletin 2010年第22期55卷 2359-2365页

作者： CHEN KeNian zhang YanBin TANG Tian shi SuHua State Key Laboratory of Biocontrol School of Life Sciences Sun Yat-Sen (Zhongshan) University Guangzhou 510275 China Department of Biotechnology Guangzhou Medical College Guangzhou 510182 China College of Computer Science Hangzhou Dianzi University Hangzhou 310018 China

As an index of functional divergence, expression divergence between duplicate gene copies has been observed and correlated with protein coding sequence divergence and bias in gene functional classes. However, the changes in the cis-regulatory region of the duplicate genes which is thought to have important role in expression divergence, has not been explored on the genome-wide scale. We analyzed functional genomics data for a large number of duplicated gene pairs formed by ancient polyploidy events in Arabidopsis thaliana. The divergence in cis-regulatory regions between two copies is positively correlated with the magnitude difference of expression. Moreover, we find that highly expressed duplicate gene pairs have a more diverged cis-regulatory region than weakly expressed gene pairs. We also show that the correlation between expression functional constraint and protein functional constraint is different in old and young duplicate pairs. Our results suggest that cis-regulatory sequence divergence contributes to the expression divergence of duplicate genes formed by genome-wide duplication. Cis-regulatory region diverges faster in highly expressed duplicate pairs. The diversify selection strengths that act on cis-regulatory region and protein coding region are negatively correlated in young duplicate pairs under expression constraint.

关键词：全基因组拟南芥独联体分歧复形监管基因表达差异蛋白质编码区

Centralized light-wave WDM-PON employing DQPSK downstream and OOK remodulated upstream signals

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 125-128页

作者： zhang Wei-feng XIN Xiang-jun zhang Qi zhang Zi-xing NAI Wei shi Yan School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

A novel architecture for wavelength-division-multiplexing passive optical network （WDM-PON） with centralized light-wave is proposed and demonstrated. At the optical line terminal （OLT） session of this architecture, optical differential quadrature phase shift keying （DQPSK） modulated signal with constant-intensity at 10 Gbit/s is utilized for downstream transmission. At the optical network unit （ONU）, part of the downstream optical power is remodulated with on-off keying （OOK） intensity modulation at 10 Gbit/s for upstream without additional laser. Simulation results show that the power penalties of the downstream for 20 km single-mode fiber （SMF） transmission and multi-channels are negligible. While for the upstream, the power penalties are obvious. The simulation results and analysis also reflect that by reducing the launch power of DQPSK transmitters, power penalties can be reduced, although the transmission distance is limited.

关键词： WDM-PON DQPSK remodulation centralizedlight sources