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Virologica Sinica 2011年第5期26卷 297-305页

作者： Ming Shan Shi-ying Zhang Lei Jiang Ming Ma guo-xun Li A Center for Advanced Invertebrate Cell Engineering Collaborated Between Boyce Thompson Institute and Qingdao Agricultural University Qingdao Agricultural University （QAU） Qingdao 266109 China Boyce Thompson Institute （BTI） at Cornell University Ithaca New York 14853 USA

It is well known that Tn5B1-4 (commercially known as the High Five) cell line is highly susceptible to baculovirus and provides superior production of recombinant proteins when compared to other insect cell *** the characteristics of the cell line do not always remain stable and may change upon continuous *** an alphanodavirus,named Tn5 Cell Line Virus (or TNCL Virus),was identified in High Five cells in ***,we established a new cell line,QB-Tn9-4s,from Trichoplusia ni,which was determined to be free of TNCL virus by RT-PCR *** this paper,we describe the development of a novel cell clone,QB-CL-B,from a low passage QB-Tn9-4s cell line and report its susceptibility to AcMNPV,and the level of recombinant protein *** cell clone was similar to its parental cells QB-Tn9-4s and Tn5B1-4 cells in morphology and growth rate;although it also showed approximately the same responses to AcMNPV infection and production of occlusion bodies,there were higher levels of recombinant protein production in comparison to QB-Tn9-4s (parental cells) and High5 cells.

关键词： Cell line Insect virus Recombinant protein expression RT-PCR TNCL virus

Roughness characterization and shearing dislocation failure for rock-backfill interface

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1167-1176页

作者： Meifeng Cai Zhilou Feng Qifeng guo Xiong Yin Minghui Ma xun Xi Key Laboratory of High-Efficient Mine and Safety of Metal Mines of Ministry of Education Beijing 100083China Key Laboratory of Urban and Underground Space Engineering University of Science and Technology BeijingBeijing 100083China Shandong Gold Group Co LtdJinan 250102China

Shearing dislocation is a common failure type for rock–backfill interfaces because of backfill sedimentation and rock strata movement in backfill mining *** paper designed a test method for rock–backfill shearing *** digital image techno-logy and three-dimensional(3D)laser morphology scanning techniques,a set of 3D models with rough joint surfaces was ***,the mechanical behavior of rock–backfill shearing dislocation was investigated using a direct shear *** effects of interface roughness on the shear–displacement curve and failure characteristics of rock–backfill specimens were *** 3D fractal dimen-sion,profile line joint roughness coefficient(JRC),profile line two-dimensional fractal dimension,and the surface curvature of the frac-tures were *** correlation characterization of surface roughness was then analyzed,and the shear strength could be measured and calculated using *** results showed the following:there were three failure threshold value points in rock–backfill shearing dis-location:30%–50%displacement before the peak,70%–90%displacement before the peak,and 100%displacement before the peak to post-peak,which could be a sign for rock–backfill shearing dislocation *** surface JRC could be used to judge the rock–backfill shearing dislocation failure,including post-peak sliding,uniform variations,and gradient change,corresponding to rock–backfill disloca-tion failure on the field *** research reveals the damage mechanism for rock–backfill complexes based on the free joint surface,fills the gap of existing shearing theoretical systems for isomerism complexes,and provides a theoretical basis for the prevention and control of possible disasters in backfill mining.

关键词： rock–backfill roughness correlation characterization shearing dislocation interface failure

Updates of developments in interventional therapy for elderly patients with cardiovascular diseases

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Journal of Geriatric Cardiology 2024年第1期21卷 1-3页

作者： Hua SHEN xun-xun FENG Qian-Yun guo Yu-Jie ZHOU Beijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic Disease Beijing Institute of Heart Lung and Blood Vessel DiseaseClinical Center for Coronary Heart DiseaseDepartment of CardiologyBeijing Anzhen HospitalCapital Medical UniversityBeijingChina

Cardiovascular diseases(CVD)are the leading cause of death in the world and one of the most common diseases in the elderly,with high prevalence and poor prognosis,which seriously affect the health of the elder *** report showed that global deaths from CVD increased from 12.4 million in 1990 to 19.8 million in 2022,reflecting the global population growth and aging,as well as the impact of metabolic,environmental,and behavioral risks.[1]With the progress of aging population,the burden of CVD in the elderly in China has increased year by year,and factors including multiple complications,organ function decline,and high complication rate have made the interventional treatment of CVD in the elderly one of the difficulties and focuses in the field of cardiology in China.

关键词： diseases patients prognosis

Algebraic Properties of Toeplitz Operators on Discrete Commutative Groups

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Journal of Mathematical Research and Exposition 2008年第2期28卷 396-402页

作者： guo xun Xiang Department of Mathematics and Computer Science Gannan Normal University Jiangxi 341000 China

In this paper,a generalized Toeplitz operator is defined and some of results about the classical Toeplitz operator are *** particular,we obtain the necessary and sufficient condition for the product of two such Toeplitz operators to still be Toeplitz operator and the necessary and sufficient condition for such Toeplitz operator to be normal ***,a necessary condition for two such Toeplitz operators to be commutative is established.

关键词： discrete commutative group almost stable subset Toeplitz operator hyponormal operator Hankle operator analytic Toeplitz operator

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一种高压气体流量模糊控制策略研究

液压气动与密封 2024年第10期44卷 109-113页

作者：李嘉琪郭珣樊蕾李波刘海飞北京航天发射技术研究所北京100076

为了满足无人值守工况下流量自动调节的需求,针对航天发射场地面供气系统高压、非线性、时变等特点,设计了一种基于模糊控制的流量自动控制策略。该策略将流量误差和误差变化率进行模糊化,根据模糊控制规则获得输出量,通过控制调节阀的... 详细信息

为了满足无人值守工况下流量自动调节的需求,针对航天发射场地面供气系统高压、非线性、时变等特点,设计了一种基于模糊控制的流量自动控制策略。该策略将流量误差和误差变化率进行模糊化,根据模糊控制规则获得输出量,通过控制调节阀的开度以调节节流面积,实现流量自动调节的功能。为了完善模糊控制策略,利用AMESim软件建立了流量自动控制气路模型和控制器模型,通过仿真和试验验证了流量自动控制方案的有效性,结果表明,该方法能够实现高压气体流量的自动控制。

关键词：模糊控制流量控制仿真分析研究

Robust video question answering via contrastive cross-modality representation learning

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Science China(Information Sciences) 2024年第10期67卷 211-226页

作者： xun YANG Jianming ZENG Dan guo Shanshan WANG Jianfeng DONG Meng WANG School of Information Science and Technology University of Science and Technology of China Institute of Artificial Intelligence Hefei Comprehensive National Science Center School of Computer Science and Information Engineering Hefei University of Technology Institutes of Physical Science and Information Technology Anhui University School of Computer Science and Technology Zhejiang Gongshang University

Video question answering(VideoQA) is a challenging yet important task that requires a joint understanding of low-level video content and high-level textual semantics. Despite the promising progress of existing efforts, recent studies revealed that current VideoQA models mostly tend to over-rely on the superficial correlations rooted in the dataset bias while overlooking the key video content, thus leading to unreliable results. Effectively understanding and modeling the temporal and semantic characteristics of a given video for robust VideoQA is crucial but, to our knowledge, has not been well investigated. To fill the research gap, we propose a robust VideoQA framework that can effectively model the cross-modality fusion and enforce the model to focus on the temporal and global content of videos when making a QA decision instead of exploiting the shortcuts in datasets. Specifically, we design a self-supervised contrastive learning objective to contrast the positive and negative pairs of multimodal input, where the fused representation of the original multimodal input is enforced to be closer to that of the intervened input based on video perturbation. We expect the fused representation to focus more on the global context of videos rather than some static keyframes. Moreover, we introduce an effective temporal order regularization to enforce the inherent sequential structure of videos for video representation. We also design a Kullback-Leibler divergence-based perturbation invariance regularization of the predicted answer distribution to improve the robustness of the model against temporal content perturbation of videos. Our method is model-agnostic and can be easily compatible with various VideoQA backbones. Extensive experimental results and analyses on several public datasets show the advantage of our method over the state-of-the-art methods in terms of both accuracy and robustness.

关键词： video question answering cross-modality fusion contrastive learning cross-media reasoning

Correlation between pass-through flux of cobalt target and microstructure and magnetic properties of sputtered thin films

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Rare Metals 2021年第4期40卷 975-980页

作者： Xiu-Lan Xu Qian-Ming Huang guo-Nan Feng Gang Han Qi-xun guo Xiao-Dong Xiong Xin He Jun-Feng Luo Rong-Ming Wang Chun Feng Guang-Hua Yu School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Grikin Advanced Materials Co. LtdBeijing 102200China

Cobalt thin films were deposited on silicon substrates by magnetron sputtering two commercial cobalt targets with different pass-through fluxes(PTFs).The influences of PTF on the magnetic properties of sputtered thin films were *** results indicate that under the same sputtering conditions,cobalt thin film deposited by Co target with high PTF(84.21%) has lower remanence ratio(0.65),while cobalt thin film prepared by Co target with low PTF(69.13%) has higher remanence ratio(0.87).Through introducing an external magnetic field parallel to the film surface during sputtering processes,both the remanence ratios of cobalt thin films prepared by the two targets can be enhanced to approach ***-resolution transmission electron microscopy(HRTEM) images show that in the absence of the external magnetic field during sputtering,cobalt thin film deposited by the target with high PTF is randomly oriented in crystallographic orientations,which is due to that Co atoms have no enough time to migrate and diffuse on substrate and the atomic stacking is *** is worth mentioning that crystallographic orientations of cobalt thin film deposited by target with low PTF are relatively consistent,resulting in relatively higher remanence *** addition,HRTEM analysis indicates that the external magnetic field during sputtering drives the Co grains to arrange in a regular order with(002) orientation,leading to the improvement in remanence ratios.

关键词： Sputtering target Pass-through flux Thin film Microstructure

QuEChERS-超高效液相色谱-三重四级杆质谱法同时测定尿液和血液中22种植物毒素

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现代预防医学 2024年第4期51卷 713-721页

作者：李四生张维章剑葛成相朱国勋李昌安徐慧吴金菊合肥市疾病预防控制中心

目的以超高效液相色谱-三重四极杆质谱为检测手段，建立尿液和血液中22种植物毒素的高通量快速检测方法。方法样品经乙腈振荡提取、离心，取上清液进行QuEChERS净化处理后，基体匹配标准曲线，外标法定量，超高效液相色谱-三重四极杆... 详细信息

目的以超高效液相色谱-三重四极杆质谱为检测手段，建立尿液和血液中22种植物毒素的高通量快速检测方法。方法样品经乙腈振荡提取、离心，取上清液进行QuEChERS净化处理后，基体匹配标准曲线，外标法定量，超高效液相色谱-三重四极杆质谱的全扫描模式同时对22种目标物进行定量分析测定。比较QuEChERS方法的不同提取溶剂种类、净化剂的选择和用量对样品提取与净化的影响，通过优化液相色谱分离条件和质谱参数来提高仪器的灵敏度。结果尿液和血液中22种待测成分的回归方程线性良好，相关系数≥0.996,检出限分别为0.01～1.00μg/L和0.01～0.90μg/L,定量下限分别为：0.1～3.0μg/L和0.03～3.0μg/L,平均加标回收率分别70.5%～125%和73.7%～118%,日内精密度和日间精密度(RSD)分别为1.2%～15.2%(n=6)和1.2%～13.5%(n=6)。结论该方法快速、准确，灵敏度高，检测通量高，实现了血液和尿液中22种植物毒素的高效快速定量分析，为生物样品中痕量植物毒素测定提供了参考。

关键词：尿液血液植物毒素超高效液相色谱-三重四极杆质谱法

Biphasic effect of aspirin on apoptosis of bovine vascular endothelial cells and its molecular mechanism

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Acta Pharmacologica Sinica 2007年第3期28卷 353-358页

作者： Qing-quan CHEN Wen-lan LIU xun guo Yuan-jian LI Zhao-gui guo~1 Department of Pharmacology,School of Pharmaceutical Sciences,Central South University,Changsha 410078,China Department of Pharmacology School of Pharmaceutical Sciences Central South University Changsha China

Aim:To investigate the effect of aspirin on the apoptosis of cultured bovineaortic endothelial cells(BAEC)and the signal pathways involved in this ***:BAEC were cultured and passaged in Dulbecco’s modified Eagle’smedium culture *** changes and quantification of apoptoticcells were determined using fluorescence microscope after staining the cells withHoechst *** viability was measured by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide(MTT)*** fragmentation was visualizedby agarose gel ***-p38 mitogen-activated protein kinase(MAPK)expression was detected by Western ***:Aspirin at lowconcentrations from 1×10-10mol/L to 1×10-8mol/L decreased the apoptosis andp38 MAPK pbosphorylation induced by H2O2in BAEC,while high doses of aspi-rin(1×10-7-1×10-4mol/L)induced typical apoptotic changes in BAEC and stimu-lated the expression of phospho-p38 MAPK in a concentration-dependent ***203580,a specific p38 MAPK inhibitor,blocked such ***:Aspirin exhibits a biphasic effect on the apoptosis in BAEC,reducing apoptosisat low concentration and inducing apoptosis at high concentration,p38 MAPKmay be an important signal molecule mediating the effects of aspirin.

关键词： aspirin hydroperoxide apoptosis mitogen activated protein kinase endothelial cells

THE SPIN DELOCALIZATION SUBSTITUENT PARAMETER σ 10. SYNTHESIS OF SUBSTITUTED α, β, β-TRIFLUOROSTYRENES BY THE Pd-CATALYZED CROSS-COUPLING OF TRIFLUOROVINYLZINC BROMIDE WITH ARYL HALIDES

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Chinese Chemical Letters 1992年第10期3卷 791-794页

作者： guo Zhen JI Wen Ting SHI Hong xun guo Xi Kui JIANG Shanghai Institute of Organic Chemistry 345 Ling-ling Lu Shanghai 200032

Palladium-catalyzed coupling of trifluorovinylzinc reagent with substituted aryl halides Y-C_6H_4-X (Y=p-NO_2, p-and m-COOMe, p-COOH, p-CONH_2, p- and m-CN; X=Br, I, Cl) provides a synthetic method for α, β, β-trif... 详细信息

关键词： CF Ph Pd TRIFLUOROSTYRENES BY THE Pd-CATALYZED CROSS-COUPLING OF TRIFLUOROVINYLZINC BROMIDE WITH ARYL HALIDES SYNTHESIS OF SUBSTITUTED THE SPIN DELOCALIZATION SUBSTITUENT PARAMETER