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On Fluorophore Imaging by Diffusion Equation Model:Decompositions and Optimizations

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Acta Mathematicae Applicatae Sinica 2020年第1期36卷 203-222页

作者： Li-yan WANG ji-jun liu School of Mathematics S.T.Yau Center of Southeast UniversitySoutheast UniversityNanjing 210096China

Fluorescence imaging is a target-specific molecular imaging technology using absorption coefficient of *** this imaging model governed by an inverse problem for the coupled diffusion system,which describes the interaction of the excitation field from several boundary sources and the corresponding emission field,we reformulate it as an optimization *** solving this non-quadratic optimizing problem,we propose a decomposition scheme,which extracts the horizontal information of the target from the boundary measurement data *** realizability of this hybrid imaging scheme is rigorously proved mathematically for cubic and ellipsoid targets,by constructing an indicator function for the horizontal location of the target *** based on this horizonal location as a good initial guess for the iteration process,the cost functional is optimized efficiently using the trust domain *** implementations are provided to show the validity of the proposed scheme.

关键词： fluorescence imaging diffusion equation inverse problem decomposition optimization numerics

Bioinformatics analyses of differentially expressed genes associated with spinal cord injury:a microarray-based analysis in a mouse model

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Neural Regeneration Research 2019年第7期14卷 1262-1270页

作者： Lei Guo jing Lv Yun-Fei Huang Ding-jun Hao ji-jun liu Department of Spinal Surgery Honghui HospitalXi'an Jiaotong University Department of Clinical Laboratory Honghui HospitalXi'an Jiaotong University

Gene spectrum analysis has shown that gene expression and signaling pathways change dramatically after spinal cord injury,which may affect the microenvironment of the damaged *** analysis provides a new opportunity for investigating diagnosis,treatment,and prognosis of spinal cord ***,differentially expressed genes are not consistent among studies,and many key genes and signaling pathways have not yet been accurately ***5296 was retrieved from the Gene Expression Omnibus *** expressed genes were obtained using R/Bioconductor software(expression changed at least two-fold;P < 0.05).Database for Annotation,Visualization and Integrated Discovery was used for functional annotation of differentially expressed genes and Animal Transcription Factor Database for predicting potential transcription *** resulting transcription regulatory protein interaction network was mapped to screen representative genes and investigate their diagnostic and therapeutic value for *** total,this study identified 109 genes that were upregulated and 30 that were downregulated at 0.5,4,and 24 hours,and 3,7,and 28 days after spinal cord *** number of downregulated genes was smaller than the number of upregulated genes at each time *** for Annotation,Visualization and Integrated Discovery analysis found that many inflammation-related pathways were upregulated in injured spinal ***,expression levels of these inflammation-related genes were maintained for at least 28 ***,399 regulation modes and 77 nodes were shown in the protein-protein interaction network of upregulated differentially expressed *** the 10 upregulated differentially expressed genes with the highest degrees of distribution,six genes were transcription *** these transcription factors,ATF3 showed the greatest ***3 was upregulated within 30 minutes,and its expression levels remained high at28 days after spin

关键词： nerve regeneration spinal cord injury differentially expressed genes bioinformatics analyses Database for Annotation,Visualization and Integrated Discovery analysis inflammation Kyoto Encyclopedia of Genes and Genomes pathway microarray transcription factors neural regeneration

Alteration of the esophageal microbiota in Barrett's esophagus and esophageal adenocarcinoma

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World Journal of Gastroenterology 2019年第18期25卷 2149-2161页

作者： jing Lv Lei Guo ji-jun liu He-Ping Zhao jun Zhang ji-Han Wang Department of Clinical Laboratory Honghui HospitalXi'an Jiaotong University Department of Spinal Surgery Honghui Hospital Xi'an Jiaotong University Department of Gastroenterology Second Affiliated Hospital of Xi’an Jiaotong University

The incidence of esophageal adenocarcinoma(EAC) has increased in recent decades, and its 5-year survival rate is less than 20%. As a well-established precursor, patients with Barrett's esophagus(BE) have a persistent risk of progression to EAC. Many researchers have already identified some factors that may contribute to the development of BE and EAC, and the identified risks include gastroesophageal reflux(GER), male sex, older age, central obesity,tobacco smoking, Helicobacter pylori(H. pylori) eradication, and the administration of proton pump inhibitors(PPIs) and antibiotics. The human gut harbors trillions of microorganisms, the majority of which are bacteria. These microorganisms benefit the human host in many ways, such as helping in digestion, assisting in the synthesis of certain vitamins, promoting the development of the gastrointestinal immune system, regulating metabolism and preventing invasion by specific pathogens. In contrast, microbial dysbiosis may play important roles in various diseases, such as inflammation and cancers. The composition of the microbiota located in the normal esophagus is relatively conserved without distinct microbial preferences in the upper, middle and lower esophagus. Six major phyla constitute the esophageal microbiota, including Firmicutes,Bacteroides, Actinobacteria, Proteobacteria, Fusobacteria and TM7, similar to the oral microbiota. Streptococcus dominates the esophageal microbiota. However, the microbiota varies in different esophageal diseases compared to that in the healthy esophagus. The type Ⅰ microbiota, which is primarily composed of gram-positive bacteria, is closely associated with the normal esophagus, while type Ⅱ microbiota has enriched gram-negative bacteria and is mainly associated with the abnormal esophagus. These increased gram-negative anaerobes/microaerophiles include Veillonella, Prevotella, Haemophilus, Neisseria, Granulicatella and Fusobacterium, many of which are associated with BE. The microbial d

关键词： Barrett's esophagus esophageal adenocarcinoma microorganisms esophageal microbiota alteration dysbiosis

Preface: Studies on Inverse Problems with Applications:a Collection of Papers from Chinese Scholars

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Acta Mathematicae Applicatae Sinica 2020年第1期36卷 1-2页

作者： Gang BAO jin CHENG ji-jun liu Bo ZHANG Zhejiang University Hangzhou 200433China School of Mathematical Sciences Fudan UniversityShanghai 200433China School of Mathematics Shanghai University of Finance and EconomicsShanghai 200433China School of Mathematics Southeast UniversityNanjing 210096China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

With the promotion by both mathematics itself and the practical requirements from modern society,the interest of studies on inverse problems and ill-posed problems,at home and abroad,has been flourishing in recent *** intrinsic mathematical reasons for the studies on inverse problems come from the fact that most of the inverse problems are ill-posed,i.e.,the existence,uniqueness and stability of the solution cannot be ensured due to the configurations of the problems *** characteristic of the ill-posedness for inverse problems makes it hard to construct the(generalized)solutions,especially to keep the solutions stable with respect to the noisy input *** overcome these difficulties,some regularizing techniques should be introduced,which are closely related to many mathematical branches such as partial differential equations(PDEs),functional analysis,optimizations and numerical analysis.

关键词： Preface Studies on Inverse Problems with Applications:a Collection of Papers from Chinese Scholars

Comparison of irradiation-induced void formations in tungsten with equiaxed and columnar structures

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Tungsten 2024年第4期6卷 794-805页

作者： liu Xi jia-jun Zhao ji-jun Zhao Yuan-Yuan Wang Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education) Dalian University of Technology

Tungsten(W) has been received much attention,since it is regarded as one of the most promising plasma facing materials for fusion *** are two typical morphologies of unirradiated polycrystalline W,which have the equiaxed and columnar grains,***,the role of arrangement of grain boundary(GB) in absorbing irradiation-generated point defects is still waiting to be *** current investigation,irradiation-induced void formations in W with equiaxed and columnar microstructures are predicted,respectively,using the developed phase-field *** significant kinetic behavior,such as the generation and annihilation of point defects and the interaction between point defects and GB,is reasonably *** density,size and porosity of void formed in these two microstructures are examined and analyzed according to the effects of GB ratio,temperature and damage *** analytical results show that higher GB ratio can effectively reduce void porosity,and the columnar-grained structure has better irradiation resistance than that of the equiaxed one in the case of small grain *** importantly,the predicted void sizes changed with temperature and damage rate agree well with the experimentally measured *** work has a more beneficial contribution to the microstructural improvement of International Thermonuclear Experimental Reactor-grade W.

关键词： Grain morphology Irradiation-induced void Phase-field Tungsten

Effect of nano-graphite on mechanical properties and oxidation resistance of ZrB_(2)-SiC-graphite electrode ceramics

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Journal of Iron and Steel Research International 2024年第6期31卷 1502-1513页

作者： Bo-lin Yang Chang-liu Kuang Zheng-long liu Chao Yu Cheng-ji Deng jun Ding The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrB_(2)-based ceramic composites were prepared by spark plasma sintering using ZrB_(2) powder prepared by molten salt method as raw material and SiC and nano-graphite as *** effects of nano-graphite addition on the physical properties and oxidation resistance of ZrB_(2)-based ceramic samples were *** results show that the addition of an appropriate amount of nano-graphite can effectively improve the density of ZrB_(2)-based ceramic composites and improve the physical properties of the *** flexural strength of the ceramic sample with 8 vol.%nano-graphite reached 418.54 MPa,which was 53.14% higher than that of ZrB_(2)-SiC ceramic material(273.31 MPa),and its oxidation resistance was also significantly *** demonstrats that the addition of an appropriate amount of nano-graphite can effectively improve the physical properties and oxidation resistance of ZrB_(2)-SiC ceramic *** prolonging its service life in application and promoting the development of ZrB_(2)-based ceramic composites,it is of great significance for clean steel smelting.

关键词： ZrB_(2)-SiC-graphite electrode ceramic ZrB_(2)-based ceramic composite Nano-graphite Physical property Oxidation resistance

Risk assessment of oil and gas investment environment in countries along the Belt and Road Initiative

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Petroleum Science 2024年第2期21卷 1429-1443页

作者： Bao-jun Tang Chang-jing ji Yu-Xian Zheng Kang-Ning liu Yi-Fei Ma jun-Yu Chen Center for Energy and Environmental Policy Research Beijing Institute of TechnologyBeijing100081China School of Management and Economics Beijing Institute of TechnologyBeijing100081China Collaborative Innovation Center of Electric Vehicles in Beijing BeijingChina Sustainable Development Research Institute for Economy and Society of Beijing BeijingChina Institute of Carbon Neutrality ShanghaiTech UniversityShanghai201210China

With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of investments, it is of significant importance to research the oil and gas investment environment in these countries for China's overseas investment macro-layout. This paper proposes an indicator system including 27 indicators from 6 dimensions. On this basis, game theory models combined with global entropy method and analytic hierarchy process are applied to determine the combined weights, and the TOPSIS-GRA model is utilized to assess the risks of oil and gas investment in 76 countries along the Initiative from 2014 to 2021. Finally, the GM(1,1) model is employed to predict risk values for 2022-2025. In conclusion, oil and gas resources and political factors have the greatest impact on investment environment risk, and 12 countries with greater investment potential are selected through cluster analysis in conjunction with the predicted results. The research findings may provide scientific decisionmaking recommendations for the Chinese government and oil enterprises to strengthen oil and gas investment cooperation with countries along the Belt and Road Initiative.

关键词： Belt and Road Initiative Oil and Gas Investment Risk assessment

Isocyanide-Based One-Pot Cascade Synthesis of 3-Acyl Isoindolinones

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Chinese Journal of Chemistry 2024年第3期42卷 259-263页

作者： jia liu Yi-Ming Zhu Xiao-Ping Xu Shun-jun ji Key Laboratory of Organic Synthesis of jiangsu Province College of ChemistryChemical Engineering and Materials Science & Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow UniversitySuzhouJiangsu215123 China Suzhou Baolidi Functional Materials Research Institute SuzhouJiangsu215144 China

A series of 3-acyl-substituted isoindolinone derivatives were synthesized in a one-pot manner via the reaction of o-bromobenzaldehydes,isocyanides,and carboxylic acids in the presence of palladium catalyst and base. The reaction employing easily available starting materials features simple operation and high efficiency. The mechanistic study showed that the reaction might undergo 1) Pd-catalyzed [3+2] cyclization of o-bromobenzaldehyde with isocyanide and the re-insertion of another molecule of isocyanide,2) addition of carboxylic acid to in situ formed ketenimine followed by a rearrangement relay to give 3,3-diacyl-substituted isoindolinone derivative. Further transformations of the obtained products through decarbonylation could also be realized.

关键词： One-pot reaction Isocyanide Pd catalysis Rearrangement reaction Isoindolinone

Span-based joint entity and relation extraction augmented with sequence tagging mechanism

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Science China(Information Sciences) 2024年第5期67卷 84-98页

作者： Bin ji Shasha LI Hao XU jie YU jun MA Huijun liu jing YANG College of Computer National University of Defense Technology

Span-based joint extraction simultaneously conducts named entity recognition(NER) and relation extraction(RE) in a text span form. However, since previous span-based models rely on span-level classifications, they cannot benefit from token-level label information, which has been proven advantageous for the task. In this paper, we propose a sequence tagging augmented span-based network(STSN), a spanbased joint model that can make use of token-level label information. In STSN, we construct a core neural architecture by deep stacking multiple attention layers, each of which consists of three basic attention *** the one hand, the core architecture enables our model to learn token-level label information via the sequence tagging mechanism and then uses the information in the span-based joint extraction; on the other hand, it establishes a bi-directional information interaction between NER and RE. Experimental results on three benchmark datasets show that STSN consistently outperforms the strongest baselines in terms of F1,creating new state-of-the-art results.

关键词： joint extraction named entity recognition relation extraction span sequence tagging mechanism