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Extremal Eigenvalues of the Sturm-liouville Problems with Discontinuous Coefficients

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Numerical Mathematics(Theory,Methods and Applications) 2013年第4期6卷 657-684页

作者： Shuangbing guo Dingfang li Hui Feng Xiliang Lu School of Mathematics and Statistics Wuhan UniversityWuhan 430072HubeiChina

In this paper,an extremal eigenvalue problem to the Sturm-liouville equations with discontinuous coefficients and volume constraint is *** transformation is applied to change the problem into an equivalent minimization *** element method is proposed and the convergence for the finite element solution is established.A monotonic decreasing algorithm is presented to solve the extremal eigenvalue problem.A global convergence for the algorithm in the continuous case is proved.A few numerical results are given to depict the efficiency of the method.

关键词： Extremal eigenvalue problem Sturm-liouville problem finite element method convergence analysis

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干细胞治疗阿尔茨海默病的研究热点与前沿

中国组织工程研究 2025年第7期29卷 1475-1485页

作者：谢刘刚崔书克郭楠楠李遨宇张菁瑞河南中医药大学第一临床医学院河南省郑州市450046 河南中医药大学第一附属医院脑病科四病区河南省郑州市450000 河南中医药大学河南省郑州市450046 河南中医药大学儿科医学院河南省郑州市450000

背景:干细胞具有促进神经再生、修复受损神经、抑制炎症反应和神经细胞凋亡的作用,为阿尔茨海默病治疗提供了一种全新的途径。目的:对2004-2023年国际发表的干细胞治疗阿尔茨海默病的文献进行文献计量学分析,揭示干细胞治疗阿尔茨海默... 详细信息

背景:干细胞具有促进神经再生、修复受损神经、抑制炎症反应和神经细胞凋亡的作用,为阿尔茨海默病治疗提供了一种全新的途径。目的:对2004-2023年国际发表的干细胞治疗阿尔茨海默病的文献进行文献计量学分析,揭示干细胞治疗阿尔茨海默病的研究热点和趋势。方法:以Web of Science核心合集数据库为来源,利用Excel、VOSviewer、Citespace软件对2004-01-01/2023-10-31发表的与干细胞和阿尔茨海默病相关的文献进行年发文量、国家、机构、期刊/共被引期刊、作者和关键词等的可视化分析。结果与结论:共纳入核心文献3521篇,年发文量逐年攀升;美国是发文最多的国家,哈佛医学院是最高产的机构,Maiese kenneth是发文量最多的作者,《International Journal of Molecular Sciences》在该领域发文量最多,《PLoS One》发表的文献被引次数最多;目前干细胞治疗阿尔茨海默病领域以病理生理机制和动物实验研究为侧重点,“神经发生”“氧化应激”“细胞外囊泡”“间充质干细胞”是该领域研究的趋势热点。干细胞治疗阿尔茨海默病具有广阔的前景,未来应加强机构和作者间的交流合作,深入探索干细胞治疗阿尔茨海默病的主要机制,解决临床可能遇到的免疫排斥、有效性及安全性等问题,进一步挖掘干细胞在阿尔茨海默病治疗中的潜力。

关键词：干细胞阿尔茨海默病文献计量学可视化分析研究热点与前沿

A Cu-modified active carbon fiber significantly promoted H_(2)S and PH_(3) simultaneous removal at a low reaction temperature

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Frontiers of Environmental Science & Engineering 2021年第6期15卷 405-414页

作者： Yingwu Wang Ping Ning Ruheng Zhao Kai li Chi Wang Xin Sun Xin Song qiang lin Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China Faculty of Chemical Engineering Kunming University of Science and TechnologyKunming 650500China Hainan Normal University Haikou 571158China

Poisonous gases,such as H_(2)S and PH3,produced by industrial production harm humans and damage the *** this study,H_(2)S and PH3 were simultaneously removed at low temperature by modified activated carbon fiber(ACF)*** have considered the active metal type,content,precursor,calcination,and reaction *** results exhibited that ACF could best perform by loading 15%Cu from *** optimized calcination temperature and reaction temperature separately were 550℃ and 90℃.Under these conditions,the most removal capacity could reach 69.7 mg/g and 132.1 mg/g,*** results showed that moderate calcination temperature(550℃)is suitable for the formation of the copper element on the surface of ACF,lower or higher temperature will generate more cuprous *** both can exhibit catalytic activity,the role of the copper element is significantly *** to the exceptional dispersibility of copper(oxide),the ACF can still maintain the advantages of larger specific surface area and pore volume after loading copper,which is the main reason for better performance of related ***,increasing the copper loading amount can significantly increase the crystallinity and particle size of copper(oxide)on the ACF,thereby improving its catalytic *** situ IR found that the reason for the deactivation of the catalyst should be the accumulation of generated H_(2)PO_(4)^(-) and S0_(4)^(2-)(H_(2)0)^(6) which could poison the catalyst.

关键词： ACF H_(2)S PH_(3) Cu Low temperature Simultaneous removal

The Two-step Reverse Martensitic Transformations of TiNi Shape Memory Alloy Based on Solution-treatment and Aging

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Chinese Journal of Aeronautics 2006年第B12期19卷 198-201页

作者： JIANG Da-qiang CUI li-shan ZHENG Yan-jun JIANG Xiao-hua Department of Materials Science and Engineering China University of Petroleum Beijing 102249 China

A TiNi-alloy is solution-treated in a vacuum furnace of 6.7×10^-3 Pa at 1 223 K for 3.6 ks, and then aged at 773 K for 1.8 ks. The differential scanning calorimetry （DSC） measurements show that after the heat-treatment, takes place a two-step reverse Martensitic transformation, from which results the two-stage recovery strain in a prestrained Martensitic TiNi-alloy wire during heating. The Vickers microhardness indentation test in cross-sectional areas of the TiNi-alloy wire indicates the compositional heterogeneity between its surface layers and its inside. The fact that the sizes of the indentation in surface layers smaller than those in the inside bears witness to the existence of slightly harder surface layers. It is believed that these phenomena are related to the compositional fluctuation caused by the evaporation and oxidization of Ti-element during the solution-treatment and heterogeneity formed during the subsequent aging treatment.

关键词： shape memory alloy (SMA) TiNi solution-treatment heterogeneity

Effects of water-borne copper on the gills and hepatopancreas of Macrobrachium rosenbergii

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Integrative Zoology 2008年第4期3卷 299-310页

作者： Na li qiang MA Jian YANG Yunlong ZHAO Jean-Claude BROCHON School of life Science East China Normal UniversityShanghaiChina Key Laboratory of Ecological Environment and Resources of Inland Fisheries Freshwater Fisheries Research CenterChinese Academy of Fishery SciencesWuxiChina National Research Center Laboratory of Biotechnology and Application Genetic PharmacologyEcole Normale Supérieure CachanCachan cedexFrance

We focused on elucidating the toxic effects of water-borne copper on the giant freshwater prawn Macrobrachium *** seven days of exposure to copper(Cu2+)at concentrations ranging from 0.01 mg L–1 to 0.5 mg L–1,three isozymes,malate dehydrogenase,alkaline phosphatase and esterase,were analyzed and compared using polyacrylamide electrophoresis(PAGE)and biochemical *** results indicated that the electrophoretic patterns of the isozymes showed a copper-concentration-related *** doses of copper stimulated strong expression of the three *** patterns of malate dehydrogenase and alkaline phosphatase gradually became weaker or even lost as the level of copper *** contrast,esterase patterns exhibited an increased molecular heterogeneity at higher copper concentrations.A transmission electron microscope was used to study ultrastructure differences in the gills and hepatopancreas of ***,and the results showed significant structural damage at increased levels of copper compared with the control *** basement mem-branes and mitochondira in the gills were seriously damaged,the cuticle electron density distribution was not homogeneous,and an infolded basement membrane,circularized nucleus,disintegrated nuclear membrane,and decreased mitochondria number and size were observed in the ***,flowing out of karyoplasms,partly falling microvilli,decreased mitochondrion,partly disappeared mitochondrial cristae,and a thinned matrix were observed in the *** findings indicate that exposure to elevated copper levels might damage the ultrastructure of the gills and hepatopancreas of *** and might further weaken their normal physical *** were quite sensitive to environmental stress and changes in isozyme elctrophoretic patterns might be effective biomarkers of environmental contamination.

关键词： copper gills hepatopancreas isozymes Macrobrachium rosenbergii polyacrylamide electrophoresis.

Cloning and sequence analysis of Sox genes in a tetraploid cyprinid fish,Tor douronensis

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Chinese Science Bulletin 2008年第13期53卷 1988-1995页

作者： guo BaoCheng li JunBing TONG ChaoBo HE ShunPing Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Graduate University of the Chinese Academy Sciences Beijing 100049 China

A PCR survey for Sox genes in a young tetraploid fish Tor douronensis (Teleostei:Cyprinidae) was per-formed to access the evolutionary fates of important functional genes after genome duplication caused by polyploidization event. Totally 13 Sox genes were obtained in Tor douronensis,which represent SoxB,SoxC and SoxE groups. Phylogenetic analysis of Sox genes in Tor douronensis provided evidence for fish-specific genome duplication,and suggested that Sox19 might be a teleost specific Sox gene member. Sequence analysis revealed most of the nucleotide substitutions between duplicated copies of Sox genes caused by tetraploidization event or their orthologues in other species are silent substitutions. It would appear that the sequences are under purifying selective pressure,strongly suggesting that they repre-sent functional genes and supporting selection against all null allele at either of two duplicated loci of Sox4a,Sox9a and Sox9b. Surprising variations of the intron length and similarities of two duplicated copies of Sox9a and Sox9b,suggest that Tor douronensis might be an allotetraploidy.

关键词：四倍体短基因基因复制基因多样性

Equivalency and unbiasedness of grey prediction models

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Journal of Systems Engineering and Electronics 2015年第1期26卷 110-118页

作者： Bo Zeng Chuan li guo Chen Xianjun Long College of Business Planning Chongqing Technology and Business University School of Management and Economics University of Electronic Science and Technology Chongqing Key Laboratory of Manufacturing Equipment Mechanism Design and Control School of Electrical & Information Engineering University of Sydney College of Mathematics & Statistics Chongqing Technology and Business University

In order to deeply research the structure discrepancy and modeling mechanism among different grey prediction models, the equivalence and unbiasedness of grey prediction models are analyzed and verified. The results show that all the grey prediction models that are strictly derived from x^（0）（k）＋az^（1）（k） = b have the identical model structure and simulation precision. Moreover, the unbiased simulation for the homogeneous exponential sequence can be accomplished. However, the models derived from dx^（1）/dt ＋ ax^（1）= b are only close to those derived from x^（0）（k）＋ az^（1）（k） = b provided that ｜a｜ has to satisfy｜a｜ 0.1; neither could the unbiased simulation for the homogeneous exponential sequence be achieved. The above conclusions are proved and verified through some theorems and examples.

关键词： system modeling grey prediction models equivalency and unbiasedness

The novel roles of circular RNAs in metabolic organs

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Genes & Diseases 2018年第1期5卷 16-23页

作者： Zhi-Chun Zhang Xiao-Long guo Xi li Biology Science Institutes Chongqing Medical UniversityChongqing 400016PR China

Circular RNAs(circRNAs)with a covalently closed loop structure which was different with linear RNAs,recently re-merged as novel regulator and exerted function in multiple biological *** deep RNA sequencing(RNA-seq)technology coupled with bioinformatic analyses,a number of circRNAs has been ***,circRNAs exhibit tissue-and development-specific expression indicating their potential biological ***,function of circRNAs as miRNA sponge has been well demonstrated in some diseases,besides,circRNAs also could function as RNA binding protein sponge and regulate alternative splicing and gene ***,Emerging evidences showed that circRNAs played a pivotal role on the development of diseases including atherosclerotic vascular disease,neurological disorders and liver diseases,and served as diagnostic or predictive biomarkers of some *** review mainly discusses the current advance of circRNAs as regulator involved in many diseases,and highlights circRNAs which have been well elucidated biological and pathogenic mechanism.

关键词： Brain Circular RNAs liver Metabolic disease Metabolism

Aquaporin-1 down regulation associated with inhibiting cell viability and inducing apoptosis of human lens epithelial cells

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International Journal of Ophthalmology(English edition) 2016年第1期9卷 15-20页

作者： Hong-Hua Zheng guo-Xing Xu Jian guo li-Cheng Fu Yao Yao Fujian Institute of Ophthalmology the First Affiliated Hospital of Fujian Medical University

AIM：To investigate the role of Aquaporin-1（AQP-1）in lens epithelial cells（LECs）and its potential target ***-1 is specifically expressed in LECs of eyes and is significant for lens homeostasis and transparency ***,AQP-1 expression in LECs was investigated to evaluate its influence on cell survival in association with its potential role in cataract formation.·M ETHODS：LECs were transfected with lentivirus carrying AQP-1 small interfering RNA（si RNA）.Real-time polymerase chain reaction（PCR）and Western blotting were conducted to detect AQP-1 expression in LECs from different ***,cell counting kit-8（CCK-8）assay and flow cytometry were performed to measure LEC proliferation and apoptosis,respectively.·RESULTS：AQP-1 expression was significantly reduced in LECs,both at m RNA and protein levels（〈0.05）,after si RNA *** cell viability was detected by CCK-8 assay in LECs with si RNA interference,compared to control cells（〈0.05）.The apoptosis rate significantly increased in cells after si RNA interference（〈0.05）.·CONCLUSION：The decreased cell viability following AQP-1 down regulation is largely due to its induction of apoptosis of ***-1 reduction might lead to changes of physiological functions in LECs,which might be associated with the occurrence and development of cataracts.

关键词： Aquaporin-1 small interfering RNA lensepithelial cells proliferation apoptosis cell counting kit-8 flow cytometry