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Local Analysis, Cardinality, and Split Trick of Quasi-biorthogonal Frame Wavelets

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Acta Mathematica Sinica,English Series 2011年第1期27卷 203-218页

作者： zhi hua zhang College of Global Change and Earth System Science Beijing Normal University Beijing 100875 P. R. China

The notion of quasi-biorthogonal frame wavelets is a generalization of the notion of orthog- onal wavelets. A quasi-biorthogonal frame wavelet with the cardinality r consists of r pairs of functions. In this paper we first analyze the local property of the quasi-biorthogonal frame wavelet and show that its each pair of functions generates reconstruction formulas of the corresponding subspaces. Next we show that the lower bound of its cardinalities depends on a pair of dual frame multiresolution analyses deriving it. Finally, we present a split trick and show that any quasi-biorthogonal frame wavelet can be split into a new quasi-biorthogonal frame wavelet with an arbitrarily large cardinality. For generality, we work in the setting of matrix dilations.

关键词： Local analysis cardinality split trick quasi-biorthogonal frame wavelets

Pointwise Convergence and Uniform Convergence of Wavelet Frame Series

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Acta Mathematica Sinica,English Series 2006年第3期22卷 653-658页

作者： zhi hua zhang Department of Mathematics University of California

Pointwise convergence and uniform convergence for wavelet frame series is a new topic. With the help of band-limited dual wavelet frames, this topic is first researched.

关键词： Wavelet frame series Wavelet orthonormal basis Uniform convergence Pointwise convergence

Decomposition and Approximation of Multivariate Functions on the Cube

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Acta Mathematica Sinica,English Series 2013年第1期29卷 119-136页

作者： zhi hua zhang College of Global Change and Earth System Science Beijing Normal University

In this paper, we present a decomposition method of multivariate functions. This method shows that any multivariate function f on [0, 1]d is a finite sum of the form ∑jФjψj, where each Фj can be extended to a smooth periodic function, each ψj is an algebraic polynomial, and each Фjψj is a product of separated variable type and its smoothness is same as f. Since any smooth periodic function can be approximated well by trigonometric polynomials, using our decomposition method, we find that any smooth multivariate function on [0, 1]d can be approximated well by a combination of algebraic polynomials and trigonometric polynomials. Meanwhile, we give a precise estimate of the approximation error.

关键词： Decomposition of multivariate functions approximation of multivariate functions fundamental polynomial projection operator classification of boundary points

MHD Control of Oblique Detonation Waves

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Chinese Physics Letters 2011年第1期28卷 134-137页

作者： SUN Xiao-Hui CHEN zhi-hua zhang huan-Hao Key Laboratory of Transient Physics Nanjing University of Science & Technology Nanjing 210094

Based on the Euler equation, the hybrid Roe/HLL scheme is employed to simulate the oblique detonation waves （ODWs）. Furthermore, ***）＇namic （MHD） control of both stable and unstable ODWs is investigated. It is shown that the stable ODW wave front can be controlled to the desired position under different inflow Mach numbers. However, for an unstable ODW, it is difficult for the MHD control to return the ODW front, but the unstable ODW turns to be stable with the Lorentz force applied in proper direction.

关键词： Fluid dynamics

Foam/Film Alternating Multilayer Structure with High Toughness and Low Thermal Conductivity Prepared via Microlayer Coextrusion

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Chinese Journal of Polymer Science 2021年第5期39卷 566-572,I0006页

作者： Qi LUO Hong-Ting PU zhi-hua zhang Xiong zhang Cheng-Long Yu Department of Polymeric Materials School of Materials Science&EngineeringTongji UniversityShanghai 201804China Key Laboratory of Advanced Civil Engineering Materials(Ministry of Education) Tongji UniversityShanghai 201804China School of Physics Science and Engineering&Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology Tongji UniversityShanghai 200092China

Multilayer membranes prepared via microlayer coextrusion have attracted wide attention due to their unique properties and broad *** present study,the foam/film alternating multilayer sheets based on ethylene-vinyl acetate copolymer(EVA)and high-density polyethylene are successfully prepared via microlayer *** cells in the sheets are single-cell-array along the foamed EVA layers with uniform cell *** addition,the effects of layer number and foam relative thickness on morphology,mechanical properties,damping and heat insulation properties are *** cell size decreases significantly with increasing layer number due to the enhanced confine *** tensile strength,elongation at break,and heat insulation also increase ***,the mechanical damping properties change little in the observed ***,with higher relative thickness of EVA foam,the sheets have lower tensile strength and lower thermal conductivity,while the damping properties are enhanced in a specific frequency *** elongation at break of the optimized sample comes to 800%and the thermal conductivity decreases to 61 mW·m^(-1)·K^(-1),which shows high toughness and low thermal conductivity,indicating a possible method for preparing materials with high toughness and heat-insulating properties.

关键词： Multilayer Foam Coextrusion Toughness Thermal conductivity

Effect of tetramethylpyrazin combined with cisplatin on VEGF,KLF4 and ADAMTS1 in lewis lung cancer mice

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Asian Pacific Journal of Tropical Medicine 2017年第8期10卷 874-878页

作者： Jian-hua Tang He-Min zhang zhi-hua zhang Xiu-Long zhang Department of Clinical Pharmacology First Affiliated Hospital of Hebei Northern CollegeZhangjiakou 075000China Department of Respiratory Medicine First Affiliated Hospital of Hebei Northern CollegeZhangjiakou China

Objective: To further explore the function of combine use of tetramethylpyrazine(TMP) and cisplatin(DDP) in lung carcinoma. Methods: We used the combination drug to treat Lewis lung cancer mice, investigated the expression level of vascular endothelial growth factor(VEGF), Kruppel-like factor 4(KLF4) and A disintegrin and metalloproteinase with thrombospondin motifs 1(ADAMTS1) and to further explore the inhibitory effects and potential mechanism of TMP combined with DDP on tumor angiogenesis. Results: The tumor growth was suppressed in TMP group, DDP group and TMP combined with DDP group. Furthermore, the weights and volume of tumor, the expression level of VEGF, KLF4 and ADAMTS1 were found significantly changed between experiment group and control group. These findings suggest that TMP with DDP had additional or synergistic effects to inhibit the tumor growth effectively, might be achieved through reducing the expression of angiogenesis promoting factor VEGF and increasing expression of angiogenesis inhibitors KLF4 and ADAMTS1. Conclusion: KLF4 and ADAMTS1 may be synergically involved in the angiogenesis in mouse Lewis lung cancer through the different signal ways.

关键词： Non-small cell lung cancer Tetramethylpyrazine Cisplatin ADAMTS1 VEGF KLF4

Cellular toxicity of isoniazid together with rifampicin and the metabolites of isoniazid on QSG-7701 hepatocytes

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Asian Pacific Journal of Tropical Medicine 2012年第4期5卷 306-309页

作者： zhi-hua zhang Jian-hua Tang zhi-Lin zhang Xiu-Long zhang Hong-Hai Wu Yan-Ning Hou Department of Respiratory Medicine First Affiliated Hospital of Hebei Northern College Department of Clinical Pharmacology First Affiliated Hospital of Hebei Northern College Department of Computed Tomography First Affiliated Hospital of Hebei Northern College Department of Respiratory Medicine.First Affiliated Hospital of Hebei Northern College Department of Pharmacology Bethune International Peace Hospital

Objective:To investigate the cellular toxicity of isoniazid together with rifampicin and the metabolites of isoniazid on cultured QSG-7701 cells ***:Isoniazid,rifampicin, mixture of rifampicin and isoniazid,acetylhydrazine,hydrazine were added in cultural media of QSG-7701 cells and cultured for 48 *** survival rate of cells was determined by MTT *** cultural media and cells were collected and the activity of lactate dehydrogenase was detected by ***:Compared with control group,the survival rate decreased significantly and the lactate dehydrogenase released from cell increased significantly in cells treated with isoniazid,rifampicin,acetylhydrazine,***,the metabolite of isoniazid produced significant damage on hepatocytes in low ***: Rifampicin together with rifampicin and metabolites of isoniazid produce cellular toxic effects and hydrazine may be the most toxiferous metabolite.

关键词： Isoniazid Rifampicin Acetylhydrazine Hydrazine QSG-7701 cell Hepatotoxicity Lactate dehydrogenase

Effect of endostar combined with cisplatin on expression of VEGF and Sema3A of Lewis lung cancer rats

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Asian Pacific Journal of Tropical Medicine 2013年第1期6卷 57-60页

作者： Ping Feng zhi-Lin zhang zhi-hua zhang Xiu-Long zhang Feng Xiang Jian-hua Tang Bao-Li Xiang Master of Respiratory Medicine Hebei Northern College Department of Respiratory Medicine First Affiliated Hospital of Hebei Northern College Department of Clinical Pharmacology First Affiliated Hospital of Hebei Northern College

Objective:To evaluate the therapeutic effect of endostar(ED) combined with cisplatin(DDP) on model of C57BL/6 rats,and to further investigate the inhibiting mechanism of endostar from tumor ***:Lewis lung cancer cells were inoculated in C57BL/6 mouse,then the mouse were randomized into control group(group A),ED(group B),DDP(group C) and ED/DDP (group D).They were treated according to the *** the expressions of VEGF and Sema3A were evaluated by ***:The weight of tumor increased in group A and *** was decreased in group C and *** tumor volume was increased in all the 4 groups. The VEGF expression of group D was obviously lower than the other group 3,but the Sema3A expressed of group D was significantly strengthener than the other group *** VEGF expression of group B and group D were obviously low especially in the 4th-8th *** correlated analysis showed that the expression VEGF and Sema3A were negatively correlated(r=-0.72, P<0.05).Conclusions:ED combined with DDP could control the tumor growth effectively,and avoid weight *** could reduce VEGF expression,and enhance Sema3A *** vessel presents transient *** is easy for DDP perfusion,and to kill tumor cells.

关键词： Lewis lung cancer Endostar DDP VEGF Sema3A

Community structure and regeneration types of Betula dahurica forest in Badaling forest center of Beijing

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Forestry Studies in China 2007年第2期9卷 152-156页

作者： zhang Yong Zheng zhi-hua zhang zhi-xiang College of Biological Sciences and Biotechnology Beijing Forestry University Beijing 100083 P. R. China

Using plant community analysis methods, we analyzed the floristic characteristics, species composition, community structure, population structure, and spatial distribution patterns of a Betula dahurica forest on the ＂1238＂ mountain of Badaling in Beijing, China. The results show that： 1） There are 33 plant species in the B. dahurica community, including 18 woody plant species. The B. dahurica forest is a monodominant community with 75.9% dominance. 2） Based on diameter at breast height （DBH） size class distribution, the population structure of B. dahurica and Acer mono--two heliophyllous and pioneer tree species-is cascade-type, with both in an increasing stage. The population structure of Ella mandshurica and T. mongolica, two shade-tolerant tree species, is inverse-J type, and they have more young seedling individuals and regenerate more stably. They are associated species of the pioneer tree species. The population structure of Quercus mongolica, as the associated species of climax species in the community, is sporadic, and its regeneration is fluctuating and random. Fraxinus rhynchophylla is a shade-tolerant tree species which has a unibar population structure and climax characteristics of pioneer tree species. The relative frequency of young seedlings reached 0.4. 3） The dominant species B. dahurica is still in an increasing stage, and the regeneration of other species is steady or partly influences the community, putting the community in the pioneer species stage. From the population structure and distribution frequency ofF. rhynchophylla, the B. dahurica forest will approach to a climax state in the future.

关键词： Betula dahurica forest community structure population structure regeneration type