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Synthesis of some new fused coumarin derivatives

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Chinese Journal of Chemistry 2000年第4期18卷 590-595页

作者： EL-DEEN Ibrahim Mohey IBRAhIM h.k. MAhMOUD F.F. Faculty of Education Suez Canal University Port-Said EgyptFaculty of Science Suez Canal University Ismailia EgyptFaculty of Science (for Girls) Al-Azhar University Nasr City Egypt

2-hydrazino-4-hydroxy-5h-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (3) was prepared via condensation of 2 with hydrazine hydrate. Treatment of 3 with methylene chloride, ethyl chloroformate, ethyl chloroacetate and benzaldehyde yielded the corresponding 2 - ( substituted ) hydrazino - 4 -hydro-xy-5h-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (4, 5, 6, and 10), followed by cyclization of 4, 5 and 6 with dimethyl formamide and fused sodium acetate under reflux, while compound 10 was cyclized with bromine and sodium acetate in acetic acid. Compound 3 reacted with β-(toloyl) acrylic acid, ethyl α-cyano-p-methoxycinnamate, diethyl malonate and acetyl chloride affording the corresponding 2-(substituted) hydrazino-4-hydroxy-5h-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (12, 13, 14, 15 and 16).

关键词： Synthesis fused coumarin derivatives cyclization

Cloning and characterization of a FLORICAULA/LEAFY ortholog, PFL, in polygamous papaya

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Cell Research 2005年第8期15卷 576-584页

作者： Paul h. MOORE,henrik h. ALBERT,Adrienne h.k. ROADER,Ray MING USDA-ARS Pacific Basin Agricultural Research Center Aiea hI 96701 USA USDA-ARS Pacific Basin Agricultural Research Center Aiea hI 96701 USA Section of Cell and Developmental Biology University of California San Diego La Jolla CA 92093 USA hawaii Agriculture Research Center Aiea hI 96701 USA

The homologous genes FLORICAULA (FLO) in Antirrhinum and LEAFY (LFY) in Arabidopsis are known to regu- late the initiation of flowering in these two distantly related plant species. These genes are necessary also for the expression of downstream genes that control floral organ identity. We used Arabidopsis LFY cDNA as a probe to clone and sequence a papaya ortholog of LFY, PFL. It encodes a protein that shares 61% identity with the Arabidopsis LFY gene and 71% identity with the LFY homologs of the two woody tree species: California sycamore (Platanus racemosa) and black cottonwood (Populus trichocarpa). Despite the high sequence similarity within two conserved regions, the N-terminal proline-rich motif in papaya PFL differs from other members in the family. This difference may not affect the gene function of papaya PFL, since an equally divergent but a functional LFY ortholog NEEDLY of Pinus radiata has been reported. Genomic and BAC Southern analyses indicated that there is only one copy of PFL in the papaya genome. In situ hybridization experiments demonstrated that PFL is expressed at a relatively low level in leaf primordia, but it is expressed at a high level in the floral meristem. Quantitative PCR analyses revealed that PFL was expressed in flower buds of all three sex types - male, female, and hermaphrodite with marginal difference between hermaphrodite and unisexual flowers. These data suggest that PFL may play a similar role as LFY in flower development and has limited effect on sex differentiation in papaya.

关键词： divergence floral meristem identity gene flower development gene expression molecular phylogeny.

Use of groundwater flow model in the analysis of a creeping landslide in western Japan

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Episodes 2006年第1期29卷 20-25页

作者： h.k. Shrestha R. Yatabe N.P. Bhandary Graduate School of Science and Engineering Ehime University Japan. Faculty of Engineering Ehime University Japan.

To predict the movement of an existing creeping landslide, monitoring and analysis of hydrological parameters are crucial This paper analyses the hydrological parameters of an existing creeping landslide site in western Japan. The groundwater flow and resulting fluctuation in pore water pressure at the slip layer of a sliding block was simulated using a groundwater flow model. A quasithree-dimensional factor of safety of the block was obtained by combining the groundwater model with slope stability analysis methods. The results show that for prediction purposes at a creeping landslide site the time series analysis using longterm data is of limited use, because the fluctuations of ground surface movement and hydrological parameters are not completely synchronized when the factor of safety of the slope soil is in the creep movement range. The ground surface movement rate dropped after each episode of relatively big movement, even when the hydrological parameters were constant. The factor of safety of the sliding block was more influenced by groundwater recharge from the hills than by rainfall. Pore water pressure fluctuation obtained from groundwater flow model resulting from specific rainfall events indicated better relations between fluctuations in pore water pressure and ground surface movement.

关键词：日本滑坡地下水流动模型动力地质

CUTIN SYNThASE 2 Maintains Progressively Developing Cuticular Ridges in Arabidopsis Sepals

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Molecular Plant 2017年第4期10卷 560-574页

作者： Lilan hong Joel Brown Nicholas A. Segerson Jocelyn k.C. Rose Adrienne h.k. Roeder Weiil institute for Ceil and Molecular Biology Cornell University Ithaca NY 14853 USA Plant Biology Section School of Integrative Plant Science Cornell University Ithaca NY 14853 USA Field of Genetics Genomics and Development Cornell University Ithaca NY 14853 USA

The cuticle is a crucial barrier on the aerial surfaces of land plants, in many plants, including Arabidopsis, the sepals and petals form distinctive nanoridges in their cuticles. however, little is known about how the formation and maintenance of these nanostructures is coordinated with the growth and development of the underlying cells. here we report the characterization of the Arabidopsis cutin synthase 2 （cus2） mutant, which causes a great reduction in cuticular ridges on the mature sepal epidermis, but only a moderate effect on petal cone cell ridges. Using scanning electron microscopy and confocal live imaging combined with quantification of cellular growth, we find that cuticular ridge formation progresses down the sepal from tip to base as the sepal grows, pCUS2：：GFP-GUS reporter expression coincides with cutic- ular ridge formation, descending the sepal from tip to base. Ridge formation also coincides with the reduction in growth rate and termination of cell division of the underlying epidermal cells. Surprisingly, cuticular ridges at first form normally in the cus2 mutant, but are lost progressively at later stages of sepal development, indicating that CUS2 is crucial for the maintenance of cuticular ridges after they are formed~ Our results reveal the dynamics of both ridge formation and maintenance as the sepal grows.

关键词： Arabidopsis thaliana cellular growth CUTIN SYNThASE2 (CUS2) cuticular ridges nanoridges sepal

Magnetostrictive Polarization Compensation on SOI Rib Waveguide

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光学学报 2003年第S1期23卷 219-220页

作者： P.S.Chan h.k. Tsang Department of Electronic Engineering The Chinese University of Hong Kong Shatin N.T. Hong KongDepartment of Electronic Engineering The Chinese University of Hong Kong Shatin N.T. Hong Kong

We proposed a novel application of magnetostriction for tuning differential -group- delay (DGD) and polarization- dependent-loss (PDL) of silicon- on -insulator waveguide. A magnetic-field induced change in PDL of ove... 详细信息

关键词： PDL in on Magnetostrictive Polarization Compensation on SOI Rib Waveguide of were

EFFECT OF COPPER ADDITION ON MEChANICAL PROPERTIES OF 4Cr16Mo

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Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 43-49页

作者： h.M. Geng X.C. Wu Y.A. Min h.B. Wang h.k. Zhang College of Materials Science and Engineering Shanghai University Shanghai 200072 China Special Steel Branch Baoshan Iron ＆ Steel Co Ltd Shanghai 200940 China

Experiments conducted to determine the effect of copper addition on the machinability of plastic mold steel, 4Cr16Mo, were presented. The machinability of mold steel 4Cr16Mo was visibly improved by adding Cu. The top wear of 4Cr16Mo with copper was less than that without copper. The Cu-rich phase had the effect of a lubricant and the heat conductivity, which reduced cutting-tool wear, improved machinability, and increased the service life of the cutting-tool. Increasing of copper addition decreased the hot-working character of 4Cr16Mo. The optimal hot-working parameters for 4Cr16Mo with copper were determined by the tensile test and the compression test. The rate of deformation should be adopted as 0.6 s-1. The heating-up temperature, initial forging temperature, and terminal forging temperature were 1200℃, 1150℃, and 950℃, respectively.

关键词： Machinability Cutting-tool hot-shortness Cu-rich phase

Complex Velocity Potential for an Ellipse and a Circle in Translation and Rotation

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 252-257页

作者： R.SUN &A.T.ChWANG (Department of Mechanical Engineering,The University of hong kong,h.k.) Department of Mechanical Engineering The University of Hong Kong Hong Kong China

This paper investigates the analytical solutions of two- dimensional Neumann- type external boundary- value problem for an ellipse and a circle in complex analysis *** transformation of harmonics between two planes is expanded in Laurent *** circle theorem is extended so as to suitto the system of the ellipse and the circle. By means of Basset’s process,the harmonic expressions of the system are found in the form of recurrence formulae which are suitable for numerical *** complex velocity potential of the system in translation and rotation is represented by the summation of the harmonic expressions.

关键词： velocity potential two bodies

PROXIMAL-PROXIMAL-GRADIENT METhOD

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Journal of Computational Mathematics 2019年第6期37卷 778-812页

作者： Ernest k.ryu Wotao Yin Department of Mathematics University of CaliforniaLos AngelesCA 90095USA

In this paper,we present the proximal-proximal-gradient method(PPG),a novel optimization method that is simple to implement and simple to *** generalizes the proximal-gradient method and ADMM and is applicable to minimization problems written as a sum of many differentiable and many non-differentiable convex *** non-differentiable functions can be *** furthermore present a related stochastic variation,which we call stochastic PPG(S-PPG).S-PPG can be interpreted as a generalization of Finito and MISO over to the sum of many coupled non-differentiable convex *** present many applications that can benefit from PPG and S-PPG and prove convergence for both *** demonstrate the empirical effectiveness of both methods through experiments on a CUDA GPU.A key strength of PPG and S-PPG is,compared to existing methods,their ability to directly handle a large sum of non-differentiable nonseparable functions with a constant stepsize independent of the number of *** non-diminishing stepsizes allows them to be fast.

关键词： Proximal-gradient ADMM Finito MISO SAGA Operator splitting Firstorder methods Distributed optimization Stochastic optimization Almost sure convergence linear convergence

生活盛宴的局外人:斯堪的纳维亚及芬兰文学中的孤独主题传统(英文)

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外国文学研究 2007年第5期29卷 22-37页

作者： h.k.里伊柯能芬兰赫尔辛基大学文艺系

19世纪晚期与20世纪早期的斯堪的纳维亚及芬兰文学的主要特征之一就是其孤独主题从"生活盛宴"的主题传统中可以有效地挖掘这一主题在h·易卜生、O·汉松、S·克尔凯郭尔、E·雷诺、A·默恩、h·瑟德尔贝里和A·斯特林堡等人的作品中可... 详细信息

19世纪晚期与20世纪早期的斯堪的纳维亚及芬兰文学的主要特征之一就是其孤独主题从"生活盛宴"的主题传统中可以有效地挖掘这一主题在h·易卜生、O·汉松、S·克尔凯郭尔、E·雷诺、A·默恩、h·瑟德尔贝里和A·斯特林堡等人的作品中可以经常发现这样的人物描写:他们或忍受孤独,或是生活盛宴外的流浪者这些作品常表现为以第一人称叙述的长、短篇小说,其主题背景在希腊、罗马哲学著作中可以找到,也可在19世纪的欧洲文学中找到,如B.贡斯当的《孤单》。乔伊斯也是一个代表。在《青年艺术家的肖像》中具有乔伊斯另一自我之称的斯蒂芬.代达勒斯就自我感觉是"世界文化盛宴的羞答答的访客";在短篇小说《痛苦的往事》中,达菲感到"他是生活盛宴的局外人"。在更后期的文学中,孤独主题传统也间或出现,如芬兰作家M.瓦尔塔里的作品。斯堪的纳维亚文学中孤独主题流行的部分原因是其他国家特别是法国世纪末理想造成的。另一方面,孤单的感觉源于新的城市生活,人类生活中所有的新发明和机器文明。

关键词：世纪末颓废孤独主题传统“流浪汉”文学