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Mesoscopic measurement of damage and shear bands of granite residual soil using Micro-CT and digital volume correlation

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Journal of Mountain Science 2023年第11期20卷 3423-3436页

作者： LI Cheng-sheng ZHANG Bing-xin liu zhi-jun KONG Ling-wei SHU Rong-jun Department of Civil and Environmental Engineering Shantou UniversityShantou 515000China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChineseAcademy of SciencesWuhan 430000China College of Civil and Architecture Engineering Chuzhou UniversityChuzhou 239000China

The mesomechanics of geotechnical materials are closely related to the macromechanical properties,especially the mesoscale evolution of shear bands,which is helpful for understanding the failure mechanism of geotechnical ***,there is lack of effective quantitative analysis method for the complex evolution mechanism of threedimensional shear *** this work,we used X-ray computed tomography(CT)to reconstruct volume images and used the digital volume correlation(DVC)method to calculate the three-dimensional strain fields of granite residual soil samples at different loading *** trend of the failure surface of the shear bands was obtained by the planar fitting method,and the connectivity index was constructed according to the projection characteristics of the shear bands on the failure trend *** results support the following findings:the connectivity index of the shear band increases rapidly and then slowly with increasing axial strain,which is characterized by a near'S'*** the stress reaches the peak value,the connectivity index of the shear bands almost exceeds *** contribution of the new shear band volume to the connectivity of the shear bands becomes increasingly small with increasing axial *** by quartz grains and stress at the initial stage,the dip angle gradually and finally approaches the included angle of the maximum shear stress from the discrete state with increasing axial *** tendency and dip angle of the resulting shear bands are dynamic,and the tendency slightly deflects with increasing loading.

关键词： Damage Shear band Digital volume correlation Micro-CT Granite residual soil

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Experimental observations of ferroelectricity in double pyrochlore Dy2Ru2O7

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Frontiers of physics 2014年第1期9卷 82-89页

作者： Zai-Chun Xu Mei-Feng liu Lin Lin Huimei liu zhi-Bo Yan jun-Ming liu Laboratory of Solid State Microstructures Nanjing University Nanjing 210093 China

Double pyrochlore Dy2Ru207 is synthesized and its magnetism and ferroelectricity below the Ru4＋ spin ordering temperature （NI00 K） are investigated. The ferroelectric transition appears at -18 K, much higher than the Dy3＋ spin ordering point at -1.8 K and lower than the Ru4＋ spin ordering point at -100 K. The measured electric polarization at ,-2 K is as big as 145℃/m2 in the polycrystalline samples. It is argued that the ferroelectricity is possibly ascribed to the electric dipole ordering arising from the collective monopole excitations in the Dy3＋ tetrahedrons in prior to the Dy3＋ spin ordering into spin-ice like state below -1.8 K.

关键词： pyrochlore oxides multiferroics magnetically induced ferroelectricity

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Automatic extraction and structuration of soil–environment relationship information from soil survey reports

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Journal of Integrative Agriculture 2019年第2期18卷 328-339页

作者： WANG De-sheng liu jun-zhi ZHU A-xing WANG Shu ZENG Can-ying MA Tianwu Key Laboratory of Virtual Geographic Environment Nanjing Normal UniversityNanjing 210023P.R.China State Key Laboratory Cultivation Base of Geographical Environment Evolution(Jiangsu Province) Nanjing 210023P.R.China Jiangsu Center for Collaborative Innovation in Geographic Information Resource Development and Application Nanjing 210023P.R.China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China Department of Geography University of Wisconsin-MadisonMadisonWI 53706USA

In addition to soil samples, conventional soil maps, and experienced soil surveyors, text about soils(e.g., soil survey reports) is an important potential data source for extracting soil–environment relationships. Considering that the words describing soil–environment relationships are often mixed with unrelated words, the first step is to extract the needed words and organize them in a structured way. This paper applies natural language processing(NLP) techniques to automatically extract and structure information from soil survey reports regarding soil–environment relationships. The method includes two steps:(1) construction of a knowledge frame and(2) information extraction using either a rule-based method or a statistic-based method for different types of information. For uniformly written text information, the rule-based approach was used to extract information. These types of variables include slope, elevation, accumulated temperature, annual mean temperature, annual precipitation, and frost-free period. For information contained in text written in diverse styles, the statistic-based method was adopted. These types of variables include landform and parent material. The soil species of China soil survey reports were selected as the experimental dataset. Precision(P), recall(R), and F1-measure(F1) were used to evaluate the performances of the method. For the rule-based method, the P values were 1, the R values were above 92%, and the F1 values were above 96% for all the involved variables. For the method based on the conditional random fields(CRFs), the P, R and F1 values for the parent material were, respectively, 84.15, 83.13, and 83.64%; the values for landform were 88.33, 76.81, and 82.17%, respectively. To explore the impact of text types on the performance of the CRFs-based method, CRFs models were trained and validated separately by the descriptive texts of soil types and typical profiles. For parent material, the maximum F1 value for the descriptive text

关键词： soil–environment relationship text natural language processing extraction structuration

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Differential mRNA Expressions in HCMV infected HUVECs

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Biomedical and Environmental Sciences 2022年第10期35卷 888-898页

作者： LYU Chang Ning LI Ji Chen AN Qi ZHANG Min ZONG Yan jun YANG Zhong Fa ZOU Xiang Yu PENG Fu jun WANG Qin liu zhi jun School of Clinical Medicine Weifang Medical UniversityWeifang 261053ShandongChina School of Basic Medical Sciences Weifang Medical UniversityWeifang 261053ShandongChina National Institute for Viral Diseases Control and Prevention China Center for Disease Control and PreventionBeijing 102206China

Objective The aim was to identify the gene expressions of human cytomegalovirus(HCMV)-infected human umbilical vein endothelial cells(HUVECs)and to study its possible pathogenic mechanism on atherosclerosis using microarray *** The gene expression differences in HCMV AD169 strain-infected HUVECs were studied by the microarray technology to explore the potential molecular mechanism of HCMV *** qPCRs were performed to verify the transcriptome *** A total of 2,583 differentially expressed genes,including 407 down-regulated genes and 2,176 up-regulated genes,were detected by the systematic bioinformatics *** Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses showed that the significantly differentially expressed genes were mainly involved in regulating protein kinase activity,inflammatory response,ubiquitination,protein phosphorylation,cell metabolism,and exosomes,among which 12 genes had significant changes and were screened by protein-protein interaction(PPI)analysis and verified by *** experimental qPCR results were consistent with the microarray *** The GO and KEGG analyses revealed that the regulation of protein kinase activity,inflammatory response,ubiquitination,protein phosphorylation,and cell metabolism played important roles in the process of endothelial cell ***,12 genes were involved in the process of HCMV infection of endothelial cells and contributed to the current understanding of the infection and pathogenic mechanisms of atherosclerosis.

关键词： Cytomegalovirus Endothelial cells Atherosclerosis Gene expressions Cell injury RNA microarrays

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Comparisons of Three Recurrent Selection Methods in the Improvement of Maize Populations

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Agricultural Sciences in China 2007年第6期6卷 657-664页

作者： PENG Ze-bin LI Ming-shun liu Xin-zhi LI jun-qiang Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

The maize population Csyn 4 was improved for three cycles with three recurrent selection methods MS1, MS1-HS, and MHSRRS in northern China. A total of 40 NC Ⅱ testcrosses were made by four testers with Csyn 4 and 10 improved populations, which were evaluated in four environments in the cropping season of 2005. Analysis of variance indicated a significant progress （P〈 0.05） in yield and other chief agronomic traits in the improved populations and testcrosses, demonstrating that the three recurrent selection methods were effective for increasing grain yield of testcrosses and improvement of general combining ability in maize population. The average grain yield increase of population Csyn 4 in MS1, MS1-HS, and MHSRRS recurrent selections was 266.7 kg ha^-1 （5.3%）, 288.0 kg ha^-1 （5.7%）, and 231.3 kg ha^-1 （4.6%） per cycle, while the grain yield of S 1 progeny of population for Csyn 4 was increased by 420.0 kg ha^-1 （10.9%）, 376.0 kg ha^-1 （9.8%）, and 414.7 kg ha^-1 （10.8%） per cycle in MS1, MS1-HS, and MHSRRS recurrent selections, respectively. Linear responses （b） in the MS1, MS1-HS, and MHSRRS recurrent selections were the same as the realized responses of the selection （G） for grain yield increase of Csyn 4 and S1 progeny of the populations. The grain yield of testcrosses increased by 3.3-5.2% on average per cycle. The value of heterosis did not display any differences amongst the different cycles of selections. The GCA for yield component traits of population Csyn 4 was improved significantly by means of three selection methods, whereas the GCA for plant height, ear height, days to silking, and days to pollen did not show significant increase in the recurrent selections. GCA for the number of tassel branches were decreased in the selections, while GCA for the number of plant leaves were increased, but the difference was not significant.

关键词： maize (Zea mays L.) population improvement recurrent selection modified S 1 family selection (MS 1),modified S 1 family-half-sib family combining selection (MS 1-HS) modified half-sib reciprocal recurrentselection (MHSRRS)

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Acute extensive portal and mesenteric venous thrombosis after splenectomy:Treated by interventional thrombolysis with transjugular approach

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World Journal of Gastroenterology 2009年第24期15卷 3038-3045页

作者： Mao-Qiang Wang Han-Ying Lin Li-Ping Guo Feng-Yong liu Feng Duan zhi-jun Wang Department of Interventional Radiology Chinese PLA General Hospital Beijing 100853 China

AIM:To present a series of cases with symptomatic acute extensive portal vein(PV)and superior mesenteric vein(SMV)thrombosis after splenectomy treated by transjugular intrahepatic approach catheter-directed thrombolysis. METHODS:A total of 6 patients with acute extensive PV-SMV thrombosis after splenectomy were treated by transjugular approach catheter-directed thrombolysis. The mean age of the patients was 41.2 *** access to the portal system via the transjugular approach,pigtail catheter fragmentation of clots, local urokinase injection,and manual aspiration thrombectomy were used for the initial treatment of PV-SMV thrombosis,followed by continuous thrombolytic therapy via an indwelling infusion catheter in the SMV,which was performed for three to six days. Adequate anticoagulation was given during treatment, throughout hospitalization,and after discharge. RESULTS:Technical success was achieved in all 6 *** improvement was seen in these patients within 12-24 h of the *** complications were *** 6 patients were discharged 6-14 d(8±2.5 d)after *** mean duration of follow-up after hospital discharge was 40±16.5 *** and contrast-enhanced computed tomography confirmed patency of the PV and SMV,and no recurrent episodes of PV-SMV thrombosis developed during the follow-up period. CONCLUSION:Catheter-directed thrombolysis via transjugular intrahepatic access is a safe and effective therapy for the management of patients with symptomatic acute extensive PV-SMV thrombosis.

关键词： Mechanical thrombectomy Portal vein Splenectomy Superior mesenteric vein Thrombolysis Thrombosis

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Model test of the stability degradation of a prestressed anchored rock slope system in a corrosive environment

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Journal of Mountain Science 2020年第10期17卷 2548-2561页

作者： LI Cong ZHANG Rong-tang ZHU Jie-bing liu zhi-jun LU Bo WANG Bin JIANG Yu-zhou liu Jie-sheng ZENG Ping School of Civil Engineering and Architecture Wuhan Polytechnic UniversityWuhan430023China Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources Changjiang River Scientific Research InstituteWuhan430010China Guangzhou Baiyun International Airport Co. Ltd.Guangzhou510406China

The long-term stability of a prestressed anchored slope might be influenced by the durability of the anchorage *** understand long-term stability of anchored rock slopes,the research presented herein evaluated the performance evolution of a prestressed anchored bedding slope system in a corrosive environment by model *** corrosion process in a prestressed anchor bar was monitored in terms of its open-circuit potential(OCP),corrosion current density(CCD),and electrochemical impedance spectroscopy(EIS).The stability of the prestressed anchored slope was evaluated by monitoring changes in anchorage force and *** experimental results show that prestress and oxygen could reduce the corrosion resistance of the anchor bar,and anchor bars in a chloride-rich environment are very susceptible to *** tendons in a corrosive environment suffer a loss of anchorage force,the prestress decreases rapidly after locking,and the rate thereof decreases until stabilising;in the later stage,corrosion leads to the reduction of the cross-sectional area of the steel bar which may cause the reduction in anchorage force *** force controls the deformation and stability of the anchored slope,the prestress loss caused by later corrosion may lead to an increased rate of displacement and stability degradation of the prestressed anchored rock slope.

关键词： Model test Bedding slope Prestressed anchorage Corrosion Electrochemical measurement

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Seismic passive earth thrust of submerged backfill with two-dimensional steady seepage

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Journal of Central South University 2015年第3期22卷 1062-1069页

作者：黄睿夏唐代刘志军 Key Laboratory of Soft Soils and Geoenvironmental Engineering of Ministry of Education (Zhejiang University) Research Center of Coastal and Urban Geotechnical Engineering Zhejiang University China Railway Eryuan Engineering Group Co. Ltd.

To investigate the seismic passive earth thrust with two-dimensional steady seepage, a general pseudo-dynamic solution was established based on the limit equilibrium analysis. This solution was purposefully applied to a waterfront gravity wall, which retains a submerged backfill with a drainage system along the backfill-structure interface. The wall was assumed to move towards the backfill to the passive failure state. And the theoretical derivation considered the pore pressures induced by the seepage, the excess pore pressures generated by the earthquake and the seismic inertial forces. Thereinto, the hydrostatic and hydrodynamic pressures were calculated by the analytical formulas, while the seismic forces were obtained by the pseudo-dynamic method. In the parametric study, the results indicate that the velocity of shear wave has a more prominent impact on the seismic passive earth thrust than that of primary wave. Both the horizontal and vertical seismic actions decrease the passive earth pressure, but the horizontal one affects the amplitude of the earth pressure coefficient more significantly. Moreover, the soil friction and the wall friction distinctly increase the seismic passive earth pressure just like the static situation. The comparison shows that the results are consistent with the previous work, which verifies its validity.

关键词： earth pressure earthquake pseudo-dynamic method seepage

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Onset of Coronary Heart Disease is Associated with HCMV Infection and Increased CD14^+CD16^+Monocytes in a Population of Weifang,China

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Biomedical and Environmental Sciences 2020年第8期33卷 573-582页

作者： LI Hong Zheng WANG Qin ZHANG Yi Yuan WANG Jin Dong WU Hong Juan ZHANG Mo Gen LI Ji Chen liu zhi jun Department of Medical Microbiology Weifang Medical UniversityWeifang 261053ShandongChina National Institute for Viral Diseases Control and Prevention China Center for Disease Control and PreventionBeijing 102206China School of Clinical Medicine Weifang Medical UniversityWeifang 261053ShandongChina Morphological Laboratory Weifang Medical UniversityWeifang 261053ShandongChina

Objective To investigate the relationship between human cytomegalovirus(HCMV)infection and peripheral blood CD14+CD16+monocytes in the pathogenesis of coronary heart disease(CHD),and to elucidate the mechanism of pathogenesis in CHD by analyzing the correlation between infection,inflammation,and CHD,to provide a basis for the prevention,evaluation,and treatment of the *** In total,192 patients with CHD were divided into three groups:latent CHD,angina pectoris,and myocardial ***-IgM and-IgG antibodies were assessed using ELISA;CD14+CD16+monocytes were counted using a five-type automated hematology analyzer;mononuclear cells were assessed using fluorescence-activated cell sorting;and an automatic biochemical analyzer was used to measure the levels of triglyceride,cholesterol,high-and low-density lipoprotein cholesterols,lipoprotein,hs-CRp and *** The positive rates of HCMV-IgM and-IgG were significantly higher in the CHD groups than in the control *** infection affects lipid metabolism to promote immune and inflammatory *** HCMV infection has a specific correlation with the occurrence and development of *** expression of CD14+CD16+mononuclear cells in the CHD group was increased accordingly and correlated with acute HCMV ***,HCMV antibody as well as peripheral blood CD14+CD16+mononuclear cells can be used to monitor the occurrence and development of CHD.

关键词： Human cytomegalovirus Coronary heart disease Antibody CD14+CD16+monocytes Weifang

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压实方式影响路基湿度场演变规律相似模拟试验研究

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岩土力学 2013年第11期34卷 3141-3144页

作者：柳志军中国矿业大学力学与建筑工程学院深部岩土力学与地下工程国家重点实验室江苏徐州221116

探究路基湿度场演变规律是解决路基工程水损害的基础问题之一,为研究路基湿度场受压实方式影响所产生的变化与分布问题,在相似准则推导的基础上构建了4种具备不同压实方式的室内路基相似物理试验模型。通过分析二维入渗方式的降雨试验结... 详细信息

探究路基湿度场演变规律是解决路基工程水损害的基础问题之一,为研究路基湿度场受压实方式影响所产生的变化与分布问题,在相似准则推导的基础上构建了4种具备不同压实方式的室内路基相似物理试验模型。通过分析二维入渗方式的降雨试验结果,总结了不同压实方式影响下路床湿度场扰动区扩距、前扰动区湿度分布、湿度梯度和路堤湿度值变化的主要规律,并阐述其作用机制以及提出了相关工程建议。研究结果表明:路床湿度扰动区扩距随着路床压实度的增加呈线性递减;整个湿度扰动区可划分为前、后两个区域,前扰动区湿度分布基本呈线性速降状态,湿度梯度值随着路床压实度的增加呈线性提高;路床压实度对其下的路堤湿度影响效果显著,综合效应表现为路堤湿度随路床压实度增加呈线性递减;工程中严格控制上部路基压实效果对防止下部路基水毁病害有显著作用。

关键词：压实方式路基湿度场演变规律相似模拟试验

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