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Chromatic number and subtrees of graphs

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Frontiers of Mathematics in China 2017年第2期12卷 441-457页

作者： Baogang XU yingli ZHANG Institute of Mathematics School of Mathematical Sciences Nanjing Normal UniversityNanjing 210023 China

Let G and H be two induced subgraph isomorphic to conjectured that, for every tree function, depending only on T graphs. We say that G induces H if G has an H. A. Gyarfas and D. Sumner, independently, T, there exists a function fT, called binding with the property that every graph G with chromatic number fT（ω（G）） induces T. A. Gyarfas, E. Szemeedi and Z. Tuza confirmed the conjecture for all trees of radius two on triangle-free graphs, and H. Kierstead and S. Penrice generalized the approach and the conclusion of A. Gyarfas et al. onto general graphs. A. Scott proved an interesting topological version of this conjecture asserting that for every integer k and every tree T of radius r, every graph G with co（G） ≤ k and sufficient large chromatic number induces a subdivision of T of which each edge is subdivided at most O（14^r-1（r - 1）!） times. We extend the approach of A. Gyarfas and present a binding function for trees obtained by identifying one end of a path and the center of a star. We also improve A. Scott＇s upper bound by modifying his subtree structure and partition technique, and show that for every integer k and every tree T of radius r, every graph with ω（G） ≤ k and sufficient large chromatic number induces a subdivision of T of which each edge is subdivided at most O（6^r-2） times.

关键词： Chromatic number clique number induced tree subdivision

Properties of TiO_2 Thin Films Prepared by Magnetron Sputtering

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Journal of Materials Science & Technology 2002年第2期18卷 101-107页

作者： WenjieZHANG yingli 等 StateLaboratoryforCorrosionandProtection InstittuteofMetalReserachTheChineseAcademyofSciencesShenyang110016China StateLaboratoryforCorrosionandProtection InstittuteofMetalReserachTheChineseAcademy

With rapid progressive application of TiO2 thin films, magnetron sputtering becomes a very interesting method to prepare such multi-functional thin films. This paper focuses on influences of various deposition processes and deposition rate on the structures and properties of TiO2 thin films. Anatase, rutile or amorphous TiO2 films with various crystalline structures and different photocatalytic, optical and electrical properties can be produced by varying sputtering gases, substrate temperature, annealing process, deposition rate and the characteristics of magnetron sputtering. This may in turn affect the functions of TiO2 films in many applications. Furthermore, TiO2-based composites films can overcome many limitations and improve the properties of TiO2 films.

关键词： TiO2 thin film magnetron sputtering deposition process composite film.

A simulation-based emergency force planning method for social security events

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Journal of Systems Engineering and Electronics 2023年第1期34卷 141-148页

作者： YANG Xuesheng WANG yingli GUAN Yong War Studies Institute Academy of Military ScienceBeijing 100091China Strategic Assessments and Consultation Institute Academy of Military ScienceBeijing 100091China

The occurrence of social security events is uncertain, and the distribution characteristics are highly complex due to a variety of external factors, posing challenges to their rapid and effective handling. The scientific and reasonable requirement evaluation of the emergency force to deal with social security events is very urgent. Based on data analysis, this paper uses the neural network, operational research, modelling and simulation to predict and analyze social security events, studies the usage rule of emergency force and deployment algorithm, and conducts simulation experiments to evaluate and compare the different force deployment schemes for selection.

关键词： social security emergency force simulation force deployment

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差异和认同:“同时代人”的追问方式

当代文坛 2025年第1期 82-86页

作者：李怡四川大学文学与新闻学院

在思想文化的追问中,“同时代人”不是一个“自明”的概念。提出“同时代人”本身属于重新探寻、反思和再认定的尝试,而不是对既有事实的概括和描述。“同时代人”其实就是我们精神指认的结果,而指认本身则属于当代人自我思想发展、精... 详细信息

在思想文化的追问中,“同时代人”不是一个“自明”的概念。提出“同时代人”本身属于重新探寻、反思和再认定的尝试,而不是对既有事实的概括和描述。“同时代人”其实就是我们精神指认的结果,而指认本身则属于当代人自我思想发展、精神求索的结果。“同时代性”或者说同代人的精神统一性往往是人们追寻的理想方向,在这个意义上,努力理解自己的“时代”和努力寻找属于自己的“同时代人”并不是一件容易的事情,“同时代人”的意义不能从世俗的套语中自然生成,它的每一种概括都可能是对权威、传统与权力的冒犯,所以定义本身是需要勇气的。

关键词：同时代人差异认同勇气

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Induced pluripotent stem cell-related approaches to generate dopaminergic neurons for Parkinson's disease

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Neural Regeneration Research 2025年第11期20卷 3193-3206页

作者： Ling-Xiao yi Hui Ren Woon Genevieve Saw Li Zeng Eng King Tan Zhi Dong Zhou National Neuroscience Institute Singapore Nanyang Technology University Singapore Department of Neurology Singapore General HospitalSingapore Signature Research Program in Neuroscience and Behavioral Disorders Duke-NUS Medical SchoolSingapore

The progressive loss of dopaminergic neurons in affected patient brains is one of the pathological features of Parkinson's disease,the second most common human neurodegenerative *** the detailed pathogenesis accounting for dopaminergic neuron degeneration in Parkinson's disease is still unclear,the advancement of stem cell approaches has shown promise for Parkinson's disease research and *** induced pluripotent stem cells have been commonly used to generate dopaminergic neurons,which has provided valuable insights to improve our understanding of Parkinson's disease pathogenesis and contributed to anti-Parkinson's disease *** current review discusses the practical approaches and potential applications of induced pluripotent stem cell techniques for generating and differentiating dopaminergic neurons from induced pluripotent stem *** benefits of induced pluripotent stem cell-based research are *** dopaminergic neuron differentiation protocols from induced pluripotent stem cells are *** emerging three-dimension-based brain organoid models compared with conventional two-dimensional cell culture are ***,limitations,challenges,and future directions of induced pluripotent stem cell–based approaches are analyzed and proposed,which will be significant to the future application of induced pluripotent stem cell-related techniques for Parkinson's disease.

关键词： dopaminergic neurons induced pluripotent stem cells Parkinson's disease stem cell approaches

Plasma Nitriding of Low Alloy Sintered Steels

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材料热处理学报 2004年第5期25卷 325-329页

作者： ShivaMansoorzadeh FakhreddinAshrafizadeh Xiao-yingli TomBell DepartmentofMaterialsEngineering IsfahanUniversityofTechnologyIsfahanIran SchoolofEngineering MetallurgyandMaterialsTheUniversityofBirminghamBirminghamUK

Fe-3Cr-0.5Mo-0.3C and Fe-3Cr-l.4Mn-0.5Mo-0.367C sintered alloys were plasma nitrided at different temperatures. Characterization was performed by microhardness measurement, optical microscopy, SEM and XRD. Both materials had similar nitriding case properties. 1.4% manganese did not change the as-sintered microstructure considerably. It was observed that monophase compound layer, formed with increasing temperature. Compound layer thickness increased with increasing temperature while nitriding depth increased up to a level and then decreased. Core softening was more pronounced at higher temperature owing to cementite coarsening.

关键词：等离子渗氮烧结钢锰显微硬度 SEM XRD

Preparation and characterization of ultrafine Fe-Cu-based catalysts for CO hydrogenation

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Journal of Natural Gas Chemistry 2008年第4期17卷 327-331页

作者： Yunlai Su yingli Wang Zhongmin Liu Department of Chemistry Institute of Industrial Catalysis Zhengzhou University Zhengzhou 450052 Henan China Applied Catalysis Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China

The ultrafine particles of a new style Fe-Cu-based catalysts for CO hydrogenation were prepared by impregnating the organic sol of Fe（OH）3 and Cu（OH）2 onto the activated Al2O3, in which the organic sol of Fe（OH）3 and Cu（OH）2 were prepared in the microemulsion of dodecylbenzenesulfonic acid sodium（S）/n-butanol（A）/toluene（O）/water with V（A）/V（O） = 0.25 and W（A）/W（S） = 1.50. This catalyst was characterized by particle size analysis, XRD and TG. The results of particle size analysis showed that Fe（OH）3 particles with a mean size of 17.1 nm and Cu（OH）2 particles with an average size of 6.65 um were obtained. TG analysis and XRD patterns suggested that 673 K is the optimal calcination temperature. CO hydrogenation produced C＋OH with a high selectivity above 58 wt% by using the ultrafine particles as catalyst, and the total alcohol yield of 0.250 g·ml^-1 ·h^-1 was obtained when the contents of Al2O3 and K were 88.61 wt% and 1.60 wt%, respectively.

关键词： microemulsion conductivity ultrafine Fe-Cu-based catalyst CO hydrogenation

Single-cell transcriptomic profiling reveals ZEB1-mediated regulation in microglial subtypes and the impact of exercise on neuroinflammatory responses

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Traditional Medicine Research 2025年第2期10卷 55-64页

作者： Jin-Fang Wu yi-Sheng Chen Yu-Chun Xie Department of Rehabilitation Medicine Jiangsu Province Geriatric HospitalNanjing 210024China Fujian Key Laboratory of Toxicant and Drug Toxicology Medical CollegeNingde Normal UniversityNingde 352100China Central Laboratory Jiangsu Province Geriatric HospitalNanjing 210024China

Background:This study aims to identify distinct cellular subtypes within brain tissue using single-cell transcriptomic analysis,focusing on specific biomarkers that differentiate cell types and the effects of traditional and exercise ***:Four samples were analyzed:older control(OC),older exercise(OE),younger control(YC),and younger exercise(YE).Single-cell RNA sequencing was used to distinguish cellular subtypes through their biomarker *** visualization included violin and t-SNE plots to illustrate biomarker expression across cell clusters such as oligodendrocytes,microglia,and ***,BV2 cells were exposed to amyloid-beta fragments to simulate Alzheimer’s disease,assessing the impact of exercise-induced cellular ***:Distinct cellular subtypes were identified:oligodendrocytes(MBP,St18),microglia(Dock8),and astrocytes(Aqp4,Gpc5).Sample OE was predominantly oligodendrocytes,while YE had more astrocytes,inhibitory neurons,and Canal-Retzius *** showed a significant presence of Olfm3+ganglion ***1 gene knockout revealed changes in SMAD family gene expression,which regulate *** stress levels were also ***:This profiling enhances our understanding of brain cellular functions and interactions,potentially informing targeted therapies in neurological *** may influence brain cell immune responses and cell death pathways by regulating specific gene expressions,offering new insights for treating neuroinflammation and degeneration.

关键词： single-cell transcriptomics brain tissue cellular subtypes biomarker expression neuronal diversity

Provenance of the Early-Middle Devonian Shugouzi Formation in the Quruqtagh,Northeastern Xinjiang:Constraints from Sandstone Geochemistry and Heavy Mineral Analysis

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 193-207页

作者： ZHANG yingli WANG Zongqi WANG Tao MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

The Early-Middle Devonian Shugouzi Formation in the Quruqtagh block consists mainly of clastic ***,their provenance has been scarcely studied since it was *** of clastic rocks was commonly used to interpret the *** heavy mineral analyses help frame the U-Pb age from zircon grains,integrated with geochemical data from detrital tourmaline and *** techniques were used to characterize components of the sediment flux and define erosion areas in the Qurugtagh block,further providing evidence about the tectonic evolution of the South Tianshan and Tarim *** maximum depositional age constrained by detrital zircon dating was Early-Middle *** diagrams for sedimentary provenance using major and trace elements indicate that continental island arc-related felsic rocks were the major source rocks for the Shugouzi *** tourmalines are dravite and *** results of detrital tourmaline electron probe microanalysis(EPMA)show that the source rocks are mainly metasedimentary rocks and *** detrital chromian spinels within the sediments are characterized by high chroumium(Cr^(#))and varying magnesium(Mg^(#)).The discrimination plots reveal that these spinels were sourced from island arc magmatic *** laser ablation inductively-coupled plasma mass spectrometry(LA-ICP-MS)U-Pb chronology of detrital zircons suggests that the sediments were derived mainly from 414-491 Ma and 744-996 Ma magmatic *** restoration,sandstone geochemistry,EPMA,and detrital zircon geochronology indicate that the source rocks were predominantly derived from Late Ordovician and Devonian magmatic rocks and subordinately from recycled Neoproterozoic magmatic *** analyses of the source areas suggest that a remnant arc still existed in the Early Devonian and the Shugouzi Formation was deposited in a passive continental margin.

关键词： Shugouzi Formation provenance analysis tectonic setting passive continental margin Quruqtagh