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Size-resolved aerosol ionic composition and secondary formation at Mount Heng in South Central China

Frontiers of Environmental Science & Engineering 2013年第6期7卷 815-826页

作者： Xinfeng WANG Wenxing WANG Likun XUE Xiaomei GAO Wei NIE Yangchun YU Yang ZHOU Lingxiao YANG Qingzhu ZHANG Tao WANG Environment research Institute Shandong University Jinan 250100 China Department of Civil and Environmental Engineering Hong Kong Polytechnic University Hong Kong China

To understand the size-resolved aerosol ionic composition and the factors influencing secondary aerosol formation in the upper boundary layer in South Central China, size-segregated aerosol samples were collected using a micro-orifice uniform deposit irnpactor （MOUDI） in spring 2009 at the summit of Mount Heng （1269 m asl）, followed by subsequent laboratory analyses of 13 inorganic and organic water-soluble ions. During non- dust-storm periods, the average PM1.8 concentration was 41.8 μg·m^-3, contributing to 55% of the PM10. Sulfates, nitrates, and ammonium, the dominant ions in the fine particles, amounted to 46.8% of the PM1.8. Compared with Mount Tai in the North China Plain, the concentrations of both fine and coarse particles and the ions contained therein were substantially lower. When the air masses from Southeast Asia prevailed, intensive biomass burning there led to elevated concentrations of sulfates, nitrates, ammonium, potassium, and chloride in the fine particles at Mount Heng. The air masses originating from the north Gobi brought heavy dust storms that resulted in the remarkable production of sulfates, ammonium, methane sulfonic acid, and oxalates in the coarse particles. Generally, the sulfates were primarily produced in the form of （NH4）2SO4 in the droplet mode via heterogeneous aqueous reactions. Only approximately one-third of the nitrates were distributed in the fine mode, and high humidity facilitated the secondary formation of fine nitrates. The heterogeneous formation of coarse nitrates and ammonium on dry alkaline dust surfaces was found to be less efficient than that on the coarse particles during non-dust-storm periods.

关键词： aerosol water-soluble ions size distributions,secondary formation dust storm Mount Heng

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A Parallel Discrete Event Simulation Engine for the Low-Earth-Orbit Satellite Constellation Networks

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China Communications 2024年第8期21卷 264-275页

作者： Su Hailong Liu Yaoqi Zhou Yiqing Shi Jinglin Li Hongguang Qian Manli Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State key Lab of Processors Institute of Computing TechnologyCASBeijing 100190China Zhongke Nanjing Mobile Communication&Computing Innovation Institute Nanjing 211135China Beijing Sylincom Technology Co. Beijing 100190China

Low-Earth-Orbit satellite constellation networks(LEO-SCN)can provide low-cost,largescale,flexible coverage wireless communication *** dynamics and large topological sizes characterize *** development and application testing of LEO-SCN are challenging to carry out in a natural *** platforms are a more effective means of technology *** available simulators have a single function and limited simulation *** needs to be a simulator for full-featured *** this paper,we apply the parallel discrete-event simulation technique to the simulation of LEO-SCN to support large-scale complex system simulation at the packet *** solve the problem that single-process programs cannot cope with complex simulations containing numerous entities,we propose a parallel mechanism and algorithms LP-NM and LP-YAWNS for *** the experiment,we use ns-3 to verify the acceleration ratio and efficiency of the above *** results show that our proposed mechanism can provide parallel simulation engine support for the LEO-SCN.

关键词： constellation low earth orbit satellite ns-3 null-message parallel discrete-event simulation

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Physical Activity,Sedentary Behavior,and the Risk of Cardiovascular Disease in Type 2 Diabetes Mellitus Patients:The MIDiab Study

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Engineering 2023年第1期20卷 26-35页

作者： Yafei Wu Guijun Qin Guixia Wang Libin Liu Bing Chen Qingbo Guan Zhongshang Yuan Xu Hou Ling Gao Chao Xu Haiqing Zhang Xu Zhang Qiu Li Yongfeng Song Fei Jing Shizhan Ma Shanshan Shao Meng Zhao Qingling Guo Nanwei Tong Hongyan Zhao Xiaomin Xie Chao Liu Zhongyan Shan Zhifeng Cheng Xuefeng Yu Shulin Chen Tao Yang Yangang Wang Dongmei Li Zhaoli Yan Lixin Guo Qiuhe Ji Wenjuan Wang Jiajun Zhao Department of Endocrinology&shandong Clinical research Center of Diabetes and Metabolic Diseases Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021China shandong key Laboratory of Endocrinology and Lipid Metabolism&shandong Prevention and Control Engineering Laboratory of Endocrine and Metabolic Diseases Shandong First Medical UniversityJinan 250021China Department of Endocrine and Metabolic Diseases The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Department of Endocrinology and Metabolism First Hospital of Jilin UniversityChangchun 130021China Department of Endocrinology and Metabolism Fujian Medical University Union HospitalFuzhou 350001China Endocrinology Department The Southwest Hospital of AMUChongqing 400038China Department of Biostatistics School of Public HealthShandong UniversityJinan 250012China Department of Endocrinology and Metabolism West China Hospital of Sichuan UniversityChengdu 610041China Department of Endocrine and Metabolic Diseases Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200020China Department of Endocrinology The First People’s Hospital of YinchuanYinchuan 750001China Department of Endocrinology Nanjing Integrated Traditional Chinese and Western Medicine Hospital(the Affiliated Hospital of Nanjing University of Traditional Chinese Medicine)Nanjing 210046China Department of Endocrinology and Metabolism&Institute of Endocrinology the First Hospital of China Medical UniversityShenyang 110000China Department of Endocrinology the Fourth Affiliated Hospital of Harbin Medical UniversityHarbin 150001China Division of Endocrinology Department of Internal MedicineTongji HospitalTongji Medical College of Huazhong University of Science and TechnologyWuhan 430030China Department of Endocrinology Yantai Yuhuangding Hospital Affiliated to Qingdao University Medical CollegeYantai 264000China Department of Endocrinology the First Affiliated Hospital of Nanjing Medical University

The aim of this study was to explore the associations of moderate-to-vigorous-intensity physical activity(MVPA)time and sedentary(SED)time with a history of cardiovascular disease(CVD)and multifactorial(i.e.,blood pressure(BP),body mass index(BMI),low-density lipoprotein cholesterol(LDL-C),and glycated hemoglobin A1c(HbA1c))control status among type 2 diabetes mellitus(T2DM)patients in China.A cross-sectional analysis of 9152 people with type 2 diabetes from the Multifactorial Intervention on Type 2 Diabetes(MIDiab)study was *** were grouped according to their self-reported MVPA time(low,<150 min·week−1;moderate,150 to<450 min·week−1;high,≥450 min·week−1)and SED time(low,<4 h·d–1;moderate,4 to<8 h·d–1;high,≥8 h·d–1).Participants who self-reported a history of CVD were identified as having a CVD *** ratios(ORs)and 95%confidence intervals(CIs)of CVD risk and multifactorial control status associated with MVPA time and SED time were estimated using mixed-effect logistic regression models,adjusting for China’s geographical region *** participants had a mean±standard deviation(SD)age of(60.87±8.44)years,44.5%were women,and 25.1%had *** adjustment for potential confounding factors,an inverse association between high MVPA time and CVD risk that was independent of SED time was found,whereas this association was not observed in the moderate-MVPA group.A higher MVPA time was more likely to have a positive effect on the control of *** with the reference group(i.e.,those with MVPA time≥450 min·week−1 and SED time<4 h·d–1),CVD risk was higher in the low-MVPA group:The OR associated with an SED time<4 h·d–1 was 1.270(95%CI,1.040–1.553)and that associated with an SED time≥8 h·d–1 was 1.499(95%CI,1.149–1.955).We found that a high MVPA time(i.e.,≥450 min·week−1)was associated with lower odds of CVD risk regardless of SED time among patients with T2DM.

关键词： Type 2 diabetes Physical activity Sedentary time Car diovascular disease

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Fabrication and modelling of Si_(3)N_(4)ceramics with radial grain alignment generated through centripetal sinter-forging

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Journal of Materials Science & Technology 2022年第31期126卷 1-14页

作者： Da-Wang Tan Zhen-Yong Lao Wei-Ming Guo Akira Kondo Takahiro Kozawa Makio Naito Kevin Plucknett Hua-Tay Lin Department of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China Joining and Welding research Institute Osaka University11-1 MihogaokaIbarakiOsaka 567-0047Japan Department of Mechanical Engineering Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada

Silicon nitride(Si_(3)N_(4))based ceramics are one of the most attractive advanced engineering materials,which have been widely used under high-speed rotational operation or for mechanical contacts across a curved *** the present study,rotationally symmetric texturing of Si_(3)N_(4),with radial grain align-ment,was obtained by centripetal sinter-forging(CSF)of a partially sintered *** average values of the included angles between the c-axis of the local Si_(3)N_(4)grain and radial direction were approxi-mately 16.4°and 11.0°,on the section plane perpendicular to the pressing direction,and parallel to both the pressing and radial directions,*** compressive strain in the pressing direction forced the ceramic body to flow towards the central axis,resulting in compressive strain in the tangential di-rection and tensile strain in the radial direction.A fundamental physical model was created to simulate the grain rotation during the 3-dimentional strain reorientation,which revealed the rod-like grain would preferentially rotate toward the center of the sample under the CSF *** addition,due to the fric-tion between the sample surface and the pressing punch,the increased shear strain could enhance the Si_(3)N_(4)grain ***,ceramics with rod-like grains perpendicular to the curved side sur-face could be anticipated by applying the centripetal forming concept in a controlled manner.

关键词： Si_(3)N_(4)ceramic Texture Radial grain alignment Modeling CSF

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Porous FeAl alloys via powder sintering:Phase transformation,microstructure and aqueous corrosion behavior

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Journal of Materials Science & Technology 2021年第27期86卷 64-69页

作者： Gang Chen Klaus-Dieter Liss Chao Chen Yuehui He Xuanhui Qu Peng Cao Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing100083PR China Materials and Engineering Science program Guangdong Technion-Israel Institute of TechnologyShantouGuangdong515063PR China Technion-Israel Institute of Technology Haifa32000Israel School of Mechanical MaterialsMechatronic and Biomedical EngineeringFaculty of Engineering&Information SciencesUniversity of WollongongWollongongNSW2522Australia State key Laboratory for Powder Metallurgy Central South UniversityChangsha410083PR China Department of Chemical and Materials Engineering The University of AucklandPrivate Bag 92019Auckland1142New Zealand MacDiarmid Institute of Advanced Materials and Nanotechnology Victoria University of WellingtonPO Box 600Wellington6140New Zealand

This study investigates the phase transformation and microstructure of porous Fe Al parts sintered from elemental powder mixtures using in-situ neutron diffraction and in-situ thermal dilatometry.A single B2 structured Fe Al phase was determined in the sintered Fe Al *** combined effects of the Kirkendall porosity,transient liquid phase,and phase transformations associated with powder sintering all contribute to the swelling phenomenon of the final sintered *** aqueous corrosion test indicates that the corrosion products include iron oxides in the porous Fe Al *** accumulation of corrosion products blocks the pore channel and decreases pore size and permeability over the soaking time.

关键词： Powder sintering Intermetallic Porous Corrosion Neutron diffraction

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MINE:A Method of Multi-Interaction Heterogeneous Information Network Embedding

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Computers, Materials & Continua 2020年第6期63卷 1343-1356页

作者： Dongjie Zhu Yundong Sun Xiaofang Li Haiwen Du Rongning Qu Pingping Yu Xuefeng Piao Russell Higgs Ning Cao School of Computer Science and Technology Harbin Institute of TechnologyWeihai264209China Department of Mathematics Harbin Institute of TechnologyWeihai264209China School of Astronautics Harbin Institute of TechnologyHarbin150001China School of Information Science and Engineering Hebei University of Science and TechnologyShijiazhuang050018China School of Mathematics and Statistics University College DublinDublinD04 V1W8Ireland School of Internet of Things and Software Technology Wuxi Vocational College of Science and TechnologyWuxi214028China

Interactivity is the most significant feature of network data,especially in social *** network embedding methods have achieved remarkable results in learning network structure and node attributes,but do not pay attention to the multi-interaction between nodes,which limits the extraction and mining of potential deep interactions between *** tackle the problem,we propose a method called Multi-Interaction heterogeneous information Network Embedding(MINE).Firstly,we introduced the multi-interactions heterogeneous information network and extracted complex heterogeneous relation sequences by the multi-interaction extraction ***,we use a well-designed multi-relationship network fusion model based on the attention mechanism to fuse multiple interactional ***,applying a multitasking model makes the learned vector contain richer semantic relationships.A large number of practical experiments prove that our proposed method outperforms existing methods on multiple data sets.

关键词： Network embedding network representation learning interactive network data mining

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Effect of NS398 on metastasis-associated gene expression in a human colon cancer cell line

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World Journal of Gastroenterology 2005年第28期11卷 4337-4343页

作者： Xue-Qin Gao Jin-Xiang Han Hai-Yan Huang Bao Song, Bo Zhu Chang-Zheng Song key Laboratory of Ministry of Public Health for Biotech-Drug Shandong Medicinal and Biotechnology Center Shandong Academy of Medical Sciences Jinan 250062Shandong Province China shandong University School of Medicine Jinan 250062 Shandong Province China

AIM： To investigate the effect of NS398 on the metastasis-associated gene expression in LoVo colorectal cancer cells.METHODS： LoVo cells were treated with NS398 at the concentration of 100 IJmol/L for 24 and 48 h respectively. Total RNA was extracted with TRIzol reagents and reverse transcribed with Superscript Ⅱ and hybridized with cDNA mlcroarray （containing oncogenes, tumor suppressor genes, signal transduction molecules, adhesive molecules, growth factors, and ESTs） fabricated in our laboratory. After normalization, the ratio of gene expression of NS398 treated to untreated LoVo cells was either 2-fold up or 0.5-fold down was defined as the differentially expressed genes. Semi-quantitative RT-PCR was used to validate the microarray results.RESULTS： Among the 447 metastasis-associated genes, 9 genes were upregulated and 8 genes were downregulated in LoVo cells treated with NS398 for 24 h compared to untreated cells. While 31 genes were upregulated and 14 genes were downregulated in LoVo cells treated with NS398 for 48 h. IGFBP-5, PAI-2, JUN,REL, BRCA1, and BRCA2 might be the new targets of NS398 in treatment of colorectal cancer.CONCLUSION： NS398 might exert its anti-metastasis effect on colorectal cancer by affecting several metastasis-associated gene expression.

关键词： NS398 Colorectal cancer gene expression Metastasis cDNA microarray

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Influence of Sr on microstructure evolution,mechanical and corrosion properties of extruded Mg-2Zn-0.5Ca alloy

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Journal of Magnesium and Alloys 2024年第9期12卷 3744-3757页

作者： Junlong Qin Lili Chang Xiaojing Su School of Materials Science and Engineering Shandong UniversityJinanShandong 250061China

Degradable Mg-Zn-Ca alloys with Sr addition were prepared by vacuum melting and hot *** of Sr on microstructure,mechanical and corrosion properties of hot extruded Mg-2Zn-0.5Ca-xSr(x=0,0.5,1.0)alloys was *** results show that Sr addition into Mg-2Zn-0.5Ca alloys produced significant grain refinement in ingots and obvious texture weakening effects in extruded *** ultimate compressive strength increased as the Sr content increased,while the ultimate tensile strength increased firstly and then declined with the increasing of Sr *** tests indicated the corrosion current density of the surface parallel to extrusion direction(ED)was much lower than that of the surface perpendicular to ***-vitro immersion tests demonstrated the increase in the pH of solution and weight loss of Mg-2Zn-0.5Ca-0.5Sr alloy remain the lowest during immersion *** best comprehensive property was obtained in Mg-2Zn-0.5Ca-0.5Sr alloy,which has the largest strength and the best corrosion resistance.

关键词： Mg-Zn-Ca-Sr alloys Extrusion Microstructure Mechanical properties Corrosion properties

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Flow-Slip Stability Behavior of Calcareous Sand Treated by Microbially Induced Carbonate Precipitation Technology

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Journal of Ocean University of China 2024年第5期23卷 1381-1389页

作者： KOU Hailei HE Xiang HOU Wangxiang LI Zhendong ZHANG Xixin AN Zhaotun LU Jiaqing College of Engineering Ocean University of ChinaQingdao 266404China

Flow-slip damage commonly destabilizes coastal *** a slope stabilization method for calcareous sands in the South China Sea is *** induced calcite precipitation is a promising,eco-friendly method for soil *** study investigates the effect of microbial treatments,initial relative density,initial cell pressure,and initial stress ratio on the flow-slip stability of calcareous sand specimens by using constant shear drained *** tests lay the foundation to study the mechanical instability of sand *** show that the microbial-treated specimens maintain stable stresses longer,take longer to reach the instability,and withstand larger volumetric *** treatment effectively enhances sand stability under constant shear drainage,with improvements amplified by higher initial relative density and initial cell *** addition,a smaller initial stress ratio reduces shear effects on the specimen and increases resistance to flow *** reveals that the flow-slip stability of calcareous sand slopes is enhanced by contact cementation,particle coating,void filling,and mutual embedment of calcium carbonate crystals.

关键词： clcareous sand microbially induced carbonate precipitation constant shear drained tests flow-slip stability

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Massive Files Prefetching Model Based on LSTM Neural Network with Cache Transaction Strategy

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Computers, Materials & Continua 2020年第5期63卷 979-993页

作者： Dongjie Zhu Haiwen Du Yundong Sun Xiaofang Li Rongning Qu Hao Hu Shuangshuang Dong Helen Min Zhou Ning Cao School of Computer Science and Technology Harbin Institute of TechnologyWeihai264209China School of Science Harbin Institute of TechnologyWeihai264209China School of Engineering Manukau Institute of TechnologyAuckland2241New Zealand College of Mathematics and Computer Science Xinyu UniversityXinyu338004China College of Information Engineering Sanming UniversitySanming365004China School of Astronautics Harbin Institute of TechnologyHarbin150001China

In distributed storage systems,file access efficiency has an important impact on the real-time nature of information *** a popular approach to improve file accessing efficiency,prefetching model can fetches data before it is needed according to the file access pattern,which can reduce the I/O waiting time and increase the system ***,prefetching model needs to mine the degree of association between files to ensure the accuracy of *** the massive small file situation,the sheer volume of files poses a challenge to the efficiency and accuracy of relevance *** this paper,we propose a massive files prefetching model based on LSTM neural network with cache transaction strategy to improve file access ***,we propose a file clustering algorithm based on temporal locality and spatial locality to reduce the computational ***,we propose a definition of cache transaction according to files occurrence in cache instead of time-offset distance based methods to extract file block feature ***,we innovatively propose a file access prediction algorithm based on LSTM neural network which predict the file that have high possibility to be *** show that compared with the traditional LRU and the plain grouping methods,the proposed model notably increase the cache hit rate and effectively reduces the I/O wait time.

关键词： Massive files prefetching model cache transaction distributed storage systems LSTM neural network

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