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Analysis on the environmental problems accompanying the high-speed urbanization of small towns in china

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Journal of Environmental Sciences 2002年第1期14卷 120-126页

作者： XU Lei, GE Jian, HUA Ying (department of Architecture, zhejiang university, hangzhou 310027, china department of Architecture Zhejiang University Hangzhou 310027

The environmental problems accompanying the rapid urbanization of many small towns like Keqiao, Shaoxing County of china and their countermeasures are presented. To settle these problems rationally as well as effectively will not only conduce to boost the environmental quality and life quality of cities, but also help to promote the development of regional economy and the realization of sustainable development.

关键词： environmental problems urbanization small towns

THE ESTIMATE AND MEASUREMENT OF TRANSVERSE WAVE INTENSITY

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Acta Mechanica Solida Sinica 1997年第3期10卷 235-245页

作者： Ming Ruisen, department of Architecture, zhejiang university, hangzhou 310027, china department of Architecture Zhejiang University Hangzhou 310027 China

Transverse waves are a type of structural waves and should be considered in the analysis of high frequency vibration because the energy carried by transverse waves increases with the increase of frequency and becomes important at high frequencies. This paper studies the estimate theory and measuring technique of the transverse wave intensity in two-dimensional homogeneous structures. In general, the intensity vector is the sum of the effective intensity vector and the intensity variation vector. Each axial intensity component is proportional to two imaginary parts of cross spectral densities and its estimate is complicated. For the special case where transverse waves propagate in one direction, the intensity variation is zero and the estimate of the intensity is simplified. The intensity technique is formed based on the finite difference principle. Transverse wave intensity can be measured using a pair of two-transducer arrays lying in the orthogonal direction for the general case or a two-transducer array lying in the propagating direction for the special case. In order to assess the measurement accuracy of transverse wave intensify, the coupling loss factors from bending to transverse waves in building structures were measured using the intensity technique and compared with the results predicted and measured using the conventional method. It is shown that the agreement between the results measured using the intensity technique and that by the conventional method is good.

关键词： transverse wave intensity estimate theory measurement accuracy

Lp integrability of trigonometric series with special varying coefficients

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Applied Mathematics:A Journal of Chinese Universities 2009年第4期24卷 402-410页

作者： WEI Bao-rong department of Mathematics,hangzhou Normal university,zhejiang 310036,china department of Mathematics Hangzhou Normal University Zhejiang China

Very recently,Yu,Le and Zhou introduced the so called Δ*B1 and Δ*B2 conditions,which are generalizations of the monotone *** applying these two new conditions,the author essentially generalizes the classical results of Chen on the necessary and sufficient conditions of the Lp integrability of trigonometric *** fact,the present paper gives the first result on the necessary and sufficient conditions of the Lp integrability of trigonometric series,where coefficients may have diffierent signs.

关键词： Lp integrability trigonometric series special varying coefficients

Rigidity for rational maps with Cantor Julia sets

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Science china Mathematics 2008年第1期51卷 79-92页

作者： ZHAI Yu department of Mathematics, zhejiang university, hangzhou 310027, china department of Mathematics Zhejiang University Hangzhou China

In this paper, we prove that two rational maps with the Cantor Julia sets are quasicon- formally conjugate if they are topologically conjugate.

关键词： Cantor Julia set rigidity puzzle piece bounded shape quasiconformally conjugate 37F12

Extension of a quantized enveloping algebra by a Hopf algebra

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Science china Mathematics 2010年第5期53卷 300-307页

作者： WU ZhiXiang department of Mathematics,zhejiang university,hangzhou 310027,china department of Mathematics Zhejiang University Hangzhou China

Suppose that H is a Hopf algebra,and g is a generalized Kac-Moody algebra with Cartan matrix A =(aij)I×I,where I is an index set and is equal to either {1,2,...,n} or the natural number set *** f,g be two mappings from I to G(H),the set of group-like elements of H,such that the multiplication of elements in the set {f(i),g(i)|i ∈I} is *** we define a Hopf algebra Hgf Uq(g),where Uq(g) is the quantized enveloping algebra of g.

关键词： quantum enveloping algebra Hopf algebra Kac-Moody algebra

Local orthogonal transform for a class of acoustic waveguides

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Progress in Natural Science:Materials International 2007年第10期17卷 1136-1146页

作者： Zhu Jianxin and Li Peng(department of Mathematics, zhejiang university, hangzhou 310027, china) department of Mathematics Zhejiang University Hangzhou 310027 China

There are some curved interfaces in acoustic waveguides. To compute wave propagation along the waveguides with some marching methods, flattening of the internal interfaces is needed. In this paper, a local orthogonal coordinate transform and an equation transform are constructed to solve the two-dimensional Helmholtz equation for the waveguides bounded by a flat top, a flat bottom and two curved internal interfaces with three layered media. The curved internal interfaces are flattened by the local orthogonal coordinate transform, and the corresponding transformed Helmholtz equation can be solved by some marching methods. This treatment can be extended in multilayered medium waveguides. The one-way reformulation based on the Dirichlet-to-Neumann (DtN) map is then used to reduce the boundary value problem to an initial value problem. Numerical implementation of the resulting operator Riccati equation uses a large range step method to discretize the range variable and a truncated local eigenfunction expansion to approximate the operators. This method is particularly useful for solving long range wave propagation problems in slowly varying waveguides with multilayered medium structure.

关键词： Helmholtz equation local orthogonal transform DtN reformulation marching method internal interface one-way reformulation.

Isoprenaline enhances local Ca2+ release in cardiac myocytes

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Acta Pharmacologica Sinica 2006年第7期27卷 927-932页

作者： Jian-xin SHEN~(2,3,42 department of Physiology,Shantou university medical College,Shantou 515041,china 3 department of Physiology,medical school of Xi'an Jiaotong university,Xi'an 710061,china department of Physiology Shantou University Medical College Shantou China department of Physiology Medical School of Xi'an Jiaotong University Xi'an China

Aim:Contraction of cardiac myocytes is controlled by the generation and ampli-fication of intracellular Ca2+*** key step of this process is the couplingbetween sarcolemma L-type Ca2+channels（LCCs）and ryanodine receptors（RyRs）in the sarcoplasmic reticulum（SR）.β-Adrenergic stimulation is an important regu-latory mechanism for this coupling *** the details underlied the globallevel,which require local Ca2+release study are still *** present study isto explore the effects of β-adrenergic stimulation on local Ca2+***:Using confocal microscopy combined with loose-seal patch-clamp approaches,effects of isoprenaline(1 μmol·L-1),a β-adrenergic agonist,on local SR Ca2+re-lease triggered by Ca2+influx through LCCs in intact rat cardiac myocytes ***:Isoprenaline increased the intensity of ensemble averagedlocal Ca2+transients,the peak of which displayed a typical bell-shaped voltage-dependence over the membrane voltages ranging from～-40mV to～+35m ***-ther analysis showed that this enhancement could be explained by the increasedcoupling fidelity（which refers the increased probability of RyRs activation upondepolarization）,and the increased amplitude of evoked Ca2+sparks(due to moreCa2+releases through local RyRs).In addition,isoprenaline decreased the firstlatency,which displayed a typical"U"-shaped voltage-dependence,showing theavailable acceleration and synchronization of β-adrenergic stimulation on intrac-ellular calcium ***:Isoprenaline enhances local Ca2+release incardiac *** results underscore the importance of regulation of β-adrenergic stimulation on local intermolecular signals between LCCs and RyRs inheart cells.

关键词： local calcium release calcium signaling cardiac myocytes isoprenaline confocal microscopy

Functional limit theorem for moving average processes generated by dependent random variables

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Progress in Natural Science:Materials International 2006年第3期16卷 266-273页

作者： LIN Zhengyan and LI Degui (department of Mathematics, zhejiang university, hangzhou 310028, china) department of Mathematics Zhejiang University Hangzhou 310028 China

Let {Xt,t≥1} be a moving average process defined by , where {bj,j≥0} is a sequence of real num- bers and {ξt,-∞ 详细信息

Let {Xt,t≥1} be a moving average process defined by , where {bj,j≥0} is a sequence of real num- bers and {ξt,-∞

关键词： functional limit theorem long memory process linear process moving average process φ-mixing.

Montelukast modulates lung CysLT1 receptor expression and eosinophilic inflammation in asthmatic mice

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Acta Pharmacologica Sinica 2004年第10期 101-106页

作者： Yan-jun ZHANG, Lei ZHANG, Shao-bin WANG, Hua-hao SHEN, Er-qing WEIdepartment of pharmacology, zhejiang university school of Medicine, hangzhou 310031 zhejiang Provincial Centre for Disease Control and Prevention, hangzhou 310009 department of Respiratory Diseases, The Second Affiliated Hospital, zhejiang university school of Medicine, hangzhou 310009, china

AIM: To determine the expressions of cysteinyl leukotriene receptors, CysLT1 and CysLT2, in airway eosinophilic inflammation of OVA-induced asthmatic mice and the modulation by montelukast, a CysLT1 receptor antagonist. METHODS: Asthma model was induced by chronic exposure to ovalbumin (OVA) in C57BL/6 mice. The eosino-phils in bronchoalveolar lavage (BAL) fluid and lung tissues were counted, IL-5 level in BAL fluid was measured, and CysLT1 and CysLT2 receptor mRNA expressions were detected by semi-quantitative RT-PCR. RESULTS: Montelukast (6 mg/kg, once per day for 20 d) significantly suppressed the increased eosinophils in BAL fluid and lung tissue, and increased IL-5 level in BAL fluid in OVA challenged mice. OVA challenge increased CysLT1 but decreased CysLT2 receptor mRNA expression. Montelukast inhibited the increased CysLT1 but not the reduced CysLT2 expression after OVA challenge. CONCLUSION: CysLT receptors are modulated immunologically, and montelukast inhibits up-regulation of CysLT1 receptor

关键词： leukotriene receptors leukotriene antagonists asthma inflammation montelukast