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Journal of Computational Mathematics 2006年第1期24卷 81-90页

作者： wen-sheng chen chen Xu Wei Lin Department of Mathematics Shenzhen University Shenzhen 518060 China Key Laboratory of Mathematics Mechanization CAS Beijing 100080 China Department of Mathematics Sun Yat-Sen University Guangzhou 510275 China

Subdivision algorithm （Stationary or Non-stationary） is one of the most active and exciting research topics in wavelet analysis and applied mathematical theory. In multidimensional non-stationary situation, its limit functions are both compactly supported and infinitely differentiable. Also, these limit functions can serve as the scaling functions to generate the multidimensional non-stationary orthogonal or biorthogonal semi-multiresolution analysis （Semi-MRAs）. The spectral approximation property of multidimensional non-stationary biorthogonal Semi-MRAs is considered in this paper. Based on nonstationary subdivision scheme and its limit scaling functions, it is shown that the multidimensional nonstationary biorthogonal Semi-MRAs have spectral approximation order r in Sobolev space H^s（R^d）, for all r ≥ s ≥ 0.

关键词： Nonstationary subdivision algorithm Biorthogonal Semi-MRAs Wavelets,Spectral approximation Sobolev space

Preparation and Microstructure of Cu/Ti_3SiC_2 Nanocomposite

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Chinese Journal of Aeronautics 2006年第B12期19卷 19-22页

作者： GU wan-li sheng wen-bin chen Zong-min School of Mechanical Engineering Shandong University of Technology Zibo 255049 China

Mixed micron-sized Cu/Ti3SiC2 （vo15%） powder was mechanically milled using agate balls and zirconia balls separately. Then followed an examination of it with the FEI-SEM. The experimental results show that, distributed homogenously in Cu matrix, the Ti3SiC2 particles have a size of about 30-50 nm after milled with agate balls for 8 h, while it remains approximately unchanged after milled with zirconia balls. The microstructure of the mixture at different ball-milling stages was also studied. Bulks of Cu/Ti3SiC2 nano-composite were fabricated by hot pressing nano-sized Cu/Ti3SiC2 powder at the temperature of 1 073 K under 100 MPa. Then came an investigation of the effects of the particle size and agglomerate state of Ti3SiC2 as well as the microstructure of Cu/Ti3SiC2 nano-composite. It was found that the nano-sized Ti3SiC2 particles distribute evenly in copper.

关键词： nanocomposite Cu Ti3SiC2 powder metallurgy

Fibrin glue-assisted for the treatment of corneal perforations using glycerin-cryopreserved corneal tissue

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International Journal of Ophthalmology(English edition) 2014年第1期7卷 62-65页

作者： Nuo Dong cheng Li wen-sheng chen wen-Juan Qin Yu-Hua Xue Hu-Ping Wu Affiliated Xiamen Eye Center of Xiamen University

AIM: To evaluate the outcomes and safety of lamellar keratoplasty(LK) assisted by fibrin glue in corneal perforations. ·METHODS: Six eyes of 6 patients affected by different corneal pathologies(2 posttraumatic corneal scar and 3 bacterial keratitis) underwent LK procedures by using fibrin glue. The mean corneal perforation diameter was 1.35 ±0.64mm(range,0.7-2.5mm),and the greatest diameter of the ulcerative stromal defect was 2.47 ± 0.77mm in average(range,1.5-3.5mm). The donor corneal lamella diameters were 0.20-mm larger and thicker than the recipient to restore a physiologic corneal thickness and shape: mean donor diameter was 8.34 ± 0.28mm(range,8.2-8.7mm) and mean thickness was 352±40.27mm(range,220-400mm). Mean follow-up was 7.33±1.97 months(range,6-11 months). Postoperatively,the graft status,graft clarity,anterior chamber response,the visual prognosis,intraocular pressures,and postoperative complications were recorded. ·RESULTS:Allthecornealperforationsweresuccessfully healed after the procedure. The best-corrected visual acuity(BCVA) ranged from 20/1 000 to 20/50 in their initial presentation,and from 20/100 to 20/20 in their last visit,showed increase in all the patients. No major complications such as graft dislocation and graft failure were noted. Neovascularization developed in the superficial stroma of donor graft in 1 case. High intraocular pressure developed on day 2 after surgery,while was remained in normal range after application of anti-glaucomatous eyedrops for 1 week in 1 case. ·CONCLUSION: Fibrin glue-assisted sutureless LK is valuable for maintaining the ocular integrity in the treatment of corneal perforations.

关键词： fibrin glue corneal perforation lamellar keratoplasty

A comparison of gene expression in mouse liver and kidney in obstructive cholestasis utilizing high-density oligonucleotide microarray technology

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World Journal of Gastroenterology 2006年第16期12卷 2536-2548页

作者： Gerald U Denk Shi-Ying Cai wen-sheng chen Aiping Lin Carol J Soroka James L Boyer Liver Center Yale University School of Medicine New Haven Connecticut United States W. M. Keck Biotechnology Resource Laboratory Yale University School of Medicine New Haven ConnecticutUnited States Department of Medicine II-GroBhadem LudwigMaximilians University Miinchen Germany Department of Gastroenterology Southwest Hospital Third Military Medical University Chongqing 400038China

AIM： To assess the effects of obstructive cholestasis on a wider range of gene expression using microarray technology. METHODS： Male C57BI_/6J mice underwent common bile duct ligation （BDL） and were matched with pairfed sham-operated controls. After 7 d, the animals were sacrificed and total RNA was isolated from livers and kidneys. Equal amounts of RNA from each tissue were pooled for each group and hybridized to Affymetrix GeneChip^MG-U74Av2 containing a total of 12488 probe sets. Data analysis was performed using GeneSpring 6.0 software. Northern analysis and immunofluorescence were used for validation. RESULTS： In sham-operated and BDL mice, 44 and 50% of 12488 genes were expressed in livers, whereas 49 and 51% were expressed in kidneys, respectively. Seven days after BDL, 265 liver and 112 kidney genes with GeneOntology annotation were up-regulated and 113 liver and 36 kidney genes were down-regulated in comparison with sham-operated controls. Many genes were commonly regulated in both tissues and metabolism-related genes represented the largest functional group. CONCLUSION： Following BDL, microarray analysis reveals a broad range of gene alterations in both liver and kidney.

关键词： Bile duct ligation Cholestasis Kidney Liver Microarray

Molecular recognition of cyclophanes in water

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Chinese Chemical Letters 2024年第5期35卷 32-44页

作者： Fang-Yuan chen wen-Chao Geng Kang Cai Dong-sheng Guo College of Chemistry State Key Laboratory of Elemento-Organic ChemistryKey Laboratory of Functional Polymer Materials(Ministry of Education)Frontiers Science Center for New Organic MatterCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300071China College of Chemistry Nankai UniversityTianjin 300071China

Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular *** mechanisms of molecular recognition in water is key to comprehending biological processes at the molecular *** the past five decades,supramolecular chemists have developed a vast array of synthetic receptors with highly diverse structures and recognition *** them,cyclophanes represent an important family of macrocyclic receptors that have been extensively *** aromatic moieties in cyclophanes not only facilitate chemical modifications to impart water solubility but also enable forming hydrophobic cavities for guest inclusion in aqueous *** by Koga et al.,who reported the first inclusion complex of cyclophanes in water and solid state,numerous water-soluble cyclophanes,including derivatives of blue box,calixarenes,resorcinarenes,pillararenes,octopusarenes,biphenarenes,coronarenes,and naphthotubes,etc.,have been synthesized and subjected to investigation of the recognition capabilities in aqueous *** review provides an overview of cyclophane receptors designed to bind organic guests in *** categorize them into two classes based on the modifications made to their hydrophobic cavities:those with“exo-functionalized hydrophobic cavities”and those with“endo-functionalized hydrophobic cavities”.We introduce their distinctive features and discuss strategies to enhance recognition affinity and *** review aims to inspire the development of novel synthetic receptors with intriguing properties and foster practical applications of cyclophanes.

关键词： Biomimetic receptor Cyclophane Molecular recognition Hydrophobic effect High-affinity Macrocycles

Function of IgD on lymphocyte activation and effect of hIgD-Fc-Ig fusion protein on human PBMC proliferation

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中国药理学与毒理学杂志 2017年第10期31卷 1017-1018页

作者： wen-sheng chen Qiong HUANG Yu-jing WU Heng-shi chen Jin DONG Wei WEI Institute of Clinical Pharmacology Anhui Medical University Key Laboratory of Antiinflammatory and Immune Medicine Ministry of Education Hefei 230032 China

OBJECTIVE This study aimed to investigate the influence of IgD on T/B cell activation and construct h IgD-Fc-Igfusion protein to competitive inhibition IgD binding with *** T/B cells were sorted by magnetic cell *** differences of m IgD and IgD-R level between different T/B cell subtypes were detected by *** IgD level was detected by *** IgD-Fc-IgG1-Fc sequence was amplified by cross-PCR and then subcloned into PET28 a(+) empty *** prokaryotic expression through escherichia coli,we obtained the h IgD-Fc-Igfusion protein by affinity *** blot was used to identify the h IgD-Fc-Igfusion *** peripheral blood monouclear cells(PBMC) and fibroblast like synoviocytes(FLS) proliferation were detected using a cell counting kit-8(CCK-8).RESULTS The percentage of CD3^+/CD4^+,CD3^+/IgD^+,CD3^+/CD4^+/IgD^+,CD3^+/IgD-R+and CD3^+/CD4^+/IgD-R+cells increased significantly in RA patients comparing to healthy *** can stimulate PBMC ***(1,3,10,30 μg·mL^(-1)) stimulate PBMC proliferation significantly after 24 *** obtained stable and active h IgD-Fc-Igfusion *** h IgD-Fc-Igfusion protein showed no effect on PBMC *** it could downregulate human IgD protein promoting proliferation effects in human *** This result suggests that IgD and IgDR play an important role on T/B cell activation in RA patients and the h IgD-Fc-Igfusion protein may competitively inhibit IgD′s function and may play an therapeutic role in autoimmune diseases.

关键词： immunoglobulin D fusion protein hIgD-Fc-Ig PBMC proliferation

Changes in global land surface frozen ground and freeze-thaw processes during 1950-2020 based on ERA5-Land data

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Advances in Climate Change Research 2024年第2期15卷 265-274页

作者： Yong YANG Ren-sheng chen Yong-Jian DING Hong-Yuan LI Zhang-wen LIU Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000China

Frozen ground(FG)plays an important role in global and regional climates and environments through changes in land freeze-thaw processes,which have been conducted mainly in different ***,the changes in land surface freeze-thaw processes under climate change on a global scale are still *** on ERA5-Land hourly land skin temperature data,this study evaluated changes in the global FG area,global land surface first freeze date(FFD),last freeze date(LFD)and frost-free period(FFP)from 1950 to *** results show that the current FG areas(1991-2020 mean)in the Northern Hemisphere(NH),Southern Hemisphere(SH),and globe are 68.50×10^(6),9.03×10^(6),and 77.53×10^(6)km^(2),which account for 72.4%,26.8%,and 60.4%of the exposed land(excluding glaciers,ice sheets,and water bodies)in the NH,SH and the globe,respectively;further,relative to 1951-1980,the FG area decreased by 1.9%,8.8%,and 2.8%,*** FG at lower latitudes degrades to intermittently FG,and intermittently FG degrades to non-frozen ground,which caused the global FG boundary to retreat to higher latitudes from 1950 to *** annual FG areas in the NH,SH,and globe all show significant decreasing trends(p<0.05)from 1950 to 2020 at-0.32×10^(6),-0.22×10^(6),and-0.54×10^(6)km^(2)per decade,*** FFP prolongation in the NH is mainly influenced by LFD advance,while in the SH it is mainly controlled by FFD *** prolongation trend of FFP in the NH(1.34 d per decade)is larger than that in the SH(1.15 d per decade).

关键词： Frozen ground Freeze-thaw processes Frost-free period First freeze date Global warming

Goal-Oriented Control Systems(GOCS):From HOW to WHAT

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 816-819页

作者： wen-Hua chen the Department of Aeronautical and Automotive Engineering Loughborough UniversityLeicestershireLE113TUU.K.

Brief:New control theory is required to underpin safe design and deployment of future highly automated systems to deal with uncertain environments and complicated tasks,enabled by AI and other advanced ***-Oriented Control Systems offer potential to transform the control system design from currently instructing a control system how to perform a task to specifying what is to be achieved.

关键词： automated instru system

p38 Signaling Mediates Naringin-Induced Osteogenic Differentiation of Porcine Metanephric Mesenchymal Cells

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Chinese Journal of Integrative Medicine 2024年第9期30卷 818-825页

作者： JI Peng-cheng XIE Yuan-sheng GUO wen-kai FU Bo chen Xiang-mei Chinese PLA Medical School Beijing100853China Department of Nephrology First Medical Center of Chinese PLA General HospitalChinese PLA Institute of NephrologyState Key Laboratory of Kidney DiseasesNational Clinical Research Center for Kidney DiseasesBeijing Key Laboratory of Kidney DiseasesBeijing100853China School of Medicine Nankai UniversityTianjin300071China

Objective:To explore the potential of metanephric mesenchymal cells(MMCs)for osteogenesis and naringin’s ability to enhance this process and its molecular ***:Porcine MMCs at 70 days of gestation were used as tool cells,cultured in osteogenic induction medium,identified by immunocytochemistry *** potential of porcine MMCs and naringin’s ability to enhance this process was tested by detecting changes in cell viability,alkaline phosphatase(ALP)activity,the expression of runt-related transcription factor 2(Runx2),osteopontin(OPN)and osteocalcin(OCN),and the formation of mineralized nodules,and the application of the p38 signaling pathway inhibitor SB203580 vitiated the osteogenesis-promoting effect of ***:Immunocytochemical staining showed that the cells were Vimentin and Six2(+),E-cadherin and CK-18(−).Naringin can activate the p38 signaling pathway to enhance the osteogenesis of porcine MMCs by increasing cell viability,ALP activity,the expressions of Runx2,OPN and OCN,and the formation of mineralized nodules(P<0.05).The application of p38 signaling pathway inhibitor SB203580 vitiated the osteogenesis-promoting effect of naringin,manifested by decreased ALP activity,the expressions of Runx2,OPN and OCN,and the formation of mineralized nodules(P<0.05).Conclusion:Naringin,the active ingredient of Chinese herbal medicine Rhizoma Drynariae for nourishing Shen(Kidney)and strengthening bone,enhances the osteogenic differentiation of renal MMCs through the p38 signaling pathway.

关键词： metanephric mesenchymal cells naringin osteogenesis differentiation

Study on the clogging mechanism of punching screen in sand control by the punching structure parameters

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Petroleum Science 2024年第1期21卷 609-620页

作者： Fu-cheng Deng Fu-Lin Gui Bai-Tao Fan Lei wen sheng-Hong chen Ning Gong Yun-chen Xiao Zhi-Hui Xu Yangtze University Jingzhou434023HubeiChina CNOOC Research Institute Ltd. Beijing100028China CNOOC Ener Tech-Drilling&Production Co. Tianjin300457China Tianjin Branch of CNOOC Ltd. Tianjin300459China

As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas ***,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the *** explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined *** to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was *** results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of *** the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control *** the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the *** the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage *** microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen

关键词： Punching screen Plugging CFD-DEM Size parameter Sand control