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Numerical Computation of High Dimensional Solitons Via Darboux Transformation

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 248-252页

作者： Zixiang ZHOU (Institute of Mathematics,Fudan University,Shanghai 2 0 0 433,China) E- mail:zxzhou@*** Institute of Mathematics Fudan University Shanghai 200433 China

Darboux transformation gives explicit soliton solutionsof nonlinear partial differential equations. Using numerical computation in each step of constructing Darboux transformation,one can get the graphs of the solitons ***(n 3) , this method greatly increases the speed and deduces the memory usage of computation comparing to the software for algebraic computation. A technical problem concerning floating overflow is discussed.

关键词： Darboux transformation numerical computation

STI571 combined with vincristine greatly suppressed the tumor formation of multidrug-resistant K562 cells in a human-nude mice xenograft model

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Chinese Medical Journal 2006年第11期119卷 911-918页

作者： GA0 Lei CHEN Li FEI Xin-hong QIU Hui-ying ZH0U Hong WANG Jian-min Department of Hematology Changhai Hospital Second Military Medical University Shanghai 200433 China

Background The development of the targeted signal transduction inhibitor STI571 has prompted us to treat chronic myeloid leukemia in different ways. Since STI571 may reverse multidrug-resistance of K562/MDR cells in vitro, we studied the effect of STI571 on multidrug-resistant K562 cells in vivo. Methods Multidrug-resistant human leukemia cell line K562-n/VCR expresses both bcr/abl fusion gene and multi-drug resistance （mdrl） gene. It is a vincristine resistant cell line subcloned from the vincristine （VCR） sensitive cell line K562-n induced by vincristine in vitro. K562-n and K562-n/VCR cells were inoculated subcutaneously into both sides of nude mice breast （5×10^6 cells/each） to establish a human leukemia xenograft model. The incidence and volume of tumor were observed. In the tumor-bearing nude mice, anti-tumor drugs vincristine, daunorubicin （DNR）, STI571, and STI571 plus VCR for the treatment of mdrl and bcr/abl double positive leukemia were studied respectively. Results The tumor incidence was 100% in the nude mice inoculated with either K562-n or K562-n/VCR. The transcription of the mdrl gene and expression of P-gp were negative in K562-n cells but positive in K562-n/VCR cells. The intracellular accumulation of DNR in K562-n cells was higher than that in K562-n/VCR cells （P〈0.05） The tumor incidence of K562-n/VCR cells in nude mice was much higher than that of K562-n cells in chemotherapy groups, and the mean volume of the tumors was also larger （P〈0.05）. STI571 combined with VCR significantly suppressed the proliferation of K562-n/VCR cells. Conclusions The MDR characteristics of K562-n/VCR in vivo were the same as in vitro. STI571 had a significant tumor-suppressing effect on VCR-sensitive leukemia ceils and a moderate effect on MDR leukemia cells. VCR combined with STI571 had an excellent tumor-suppressing effect on both K562-n/VCR and K562-n in the human-nude mice xenograft model.

关键词： K562 cells leukemia multidrug-resistance imatinib mesylate xenograft model antitumor assays

Effects of the susceptibility of rice varieties to Sogatella furcifera on nymphal development and reproduction of Microvelia horvathi through a food chain

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Insect Science 2007年第4期14卷 317-321页

作者： TIE-GUANG XIA0 JIANG-XIA TANG Institute of Insect Ecology Hunan Agricultural UniversityChangshaChina

The effects of four rice varieties highly susceptible （ Xiang-Zao-Xian31 and Jia-Yu 164 ）, moderately susceptible （ Wei-You402 ）, and resistant （ Zhu-Liang-You02 ） to the whitebacked planthopper Sogatellafurcifera on the nymphal development, reproduc- tion and survival of Microvelia horoathi were investigated through a food chain using SogateUafurcifera as herbivore prey. Significant longer nymphal developmental time were observed in the 1 st, 4th, 5th instar and whole nymphal stage of M. horvathi raised on S. furcifera fed ZLY02 and WY402 than those of the other two varieties. M. horvathi raised on S. furcifera fed resistant ZLY02 showed a significant lower survival of whole nymphal stage than those fed other three susceptible varieties. Moreover, M. horvathi raised on S. furcifera fed resistant ZLY02 had shorter female longevity and lower lifetime fecundity than those of on susceptible XZX3l. Our results suggest that the S. furcifera- resistant rice variety ZLY02 had a negative effect on the growth and development of the predator M. horvathi through a food chain.

关键词： development food Microvelia horoathi rice variety Sogatellafurcifera,tritrophic interaction

Effects of Plant Residue Decomposition on Soil N Availability,Microbial Biomass and β-Glucosidase Activity During Soil Fertility Improvement in Ghana

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Pedosphere 2019年第5期29卷 608-618页

作者： Samuel T. PARTEY Robert B. Z0UGM0RE Naresh V. THEVATHASAN Richard F. PREZIOSI CGI AR CCAFS West Africa ProgramInternational Crops Research Institute for the Semi-Arid Tropics (ICRISAT)Bamako B.P. Box 320 (Mali) School of Environmental Sciences University of GuelphGuelph NIG 2W1 (Canada) Faculty of Life Sciences The University of ManchesterManchester M13 9PL (UK)

With limited use of inorganic fertilizers on smallholder farms,plant residues could be viable alternatives for soil fertility *** study was conducted to determine how residue quality and decomposition of nine plant species influence soil N availability,microbial biomass,andβ-glucosidase activity during soil fertility *** differences in N concentration were found among the species,ranging from 12.2 g kg-1 in Zea mays to 39.2 g kg-1 in Baphia *** C/N ratio was the highest in ***(34.4),whereas lignin and polyphenol concentrations were the greatest in Acacia *** highest decomposition rate(0.251%per day)occurred in Tithonia diversifolia,and the lowest in ***,Albizia zygia,***,and ***,with the half-lives of 28-56 *** 80%and 89%of N,P,K,Ca,and Mg were released from *** in 7 d,compared with over 70%retention in ***,***,and *** decomposition and nutrient release half-lives of Gliricidia sepium,Leucaena leucocephala,Azadirachta indica,and Senna spectabilis were less than 14 *** mineral N,microbial biomass,andβ-glucosidase activity increased under all treatments,with *** having the greatest *** N mineralization occurred in all of the species throughout the experiment,an initial N immobilization was recorded in the ***,***,***,and *** treatments for up to 14 *** and nutrient release rates,mineral N,soil microbial biomass,andβ-glucosidase activity were dependent on residue quality,and P and lignin levels,the lignin/N ratio,and the(lignin+polyphenol)/N ratio had the most significant effects(P≤0.05).

关键词： leguminous species litter quality microbial activity N mineralization nutrient release organic matter

BASIC FORMULATION OF STATIC AND DYNAMIC BEHAVIOURS OF SOIL AND OTHER POROUS MEDIA

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Applied Mathematics and Mechanics(English Edition) 1982年第4期3卷 457-468页

作者： 0.C.Zienkiewicz University of Wales. Swansea. U. K. Department of Civil Engineering

This paper treats the soil and rock or concrete as a two-phasemedium composed of a solid skeleton and an interstitial ***-der the unsaturated condition of interstitial fluid,the thirdphase is taken into consideration. In this paper. we consider theconstitutive relation,dynamic and kinematic relations,and also va-rious approximations with their limits of *** thoseof most practical engineering situations such as the consolidationproblem and the undrained behaviour. The finite element discreti-zation and the time dependent solution of various classes of soilproblem are also discussed.

关键词： BASIC FORMULATION OF STATIC AND DYNAMIC BEHAVIOURS OF SOIL AND OTHER POROUS MEDIA

Synthesis and photocurrent response of porphyrin-containing conjugated polymers

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Chinese Science Bulletin 2006年第11期51卷 1287-1295页

作者： ZHAO Jinling LI Binsong B0 Zhishan State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Porphyrin-containing conjugated poly- mers with fluorene or carbazole as spacer groups were prepared by Sonogashira cross-coupling reac- tions. The polymers were of high molecular weight and the flexible alkyl chains on fluorene or carbazole units made the conjugated polymers soluble in common organic solvents, such as THF and methyl- ene chloride. The polymers could form high quality durable films from solution casting. Their optical and photocurrent responsive properties were investigated. It was found that the photocurrent response was di- rectly proportional to the content of porphyrin. The incorporation of carbazole units into the polymer chains also gave positive contribution to the photo- current generation in some extent.

关键词：卟啉共轭聚合物光电流响应合成

体裁即“结构”——卡尔·达尔豪斯音乐体裁理论思想述评

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中央音乐学院学报 2023年第4期173卷 120-138页

作者：毛羽中央音乐学院音乐学系西方音乐史教研室

文章以20世纪德国音乐学家卡尔·达尔豪斯有代表性的音乐体裁文论为基础,从音乐体裁概念的内涵与基本特征、音乐体裁历史的系统性、音乐体裁系统的历史性、结构史视域下的音乐体裁理论四个方面对其音乐体裁理论思想进行分析与论述,阐明... 详细信息

文章以20世纪德国音乐学家卡尔·达尔豪斯有代表性的音乐体裁文论为基础,从音乐体裁概念的内涵与基本特征、音乐体裁历史的系统性、音乐体裁系统的历史性、结构史视域下的音乐体裁理论四个方面对其音乐体裁理论思想进行分析与论述,阐明其结构史特性、理论与实践意义以及局限。达尔豪斯认为,音乐体裁由标志复合体界定,在历史中形成系统,关于音乐体裁的理论应当在历史音乐学与系统音乐学的融合中、在结构史的视域下加以建构。这些观点有着鲜明的“达式音乐结构史”思维特征,对音乐体裁的研究有着极大的启发意义。

关键词：音乐体裁达尔豪斯标志复合体结构史

Entry qualifications and academic performance of architecture students in Nigerian Polytechnics： Are the admission requirements still relevant？

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Frontiers of Architectural Research 2014年第1期3卷 69-75页

作者： Peter 0 Adewale Olasunmbo Bolanle Adhuze Department of Architectural Technology The Federal Polytechnic Ado-Ekiti Ekiti-State Nigeria

The competence of fresh graduates of architecture has been continuously criticized by the industry for inadequate knowledge. This is often blamed on the poor standard of education evidenced by poor performances in professional and degree/diploma examinations conducted by various schools of architecture in the country. Although, factors responsible for the scenario are wetl documented in the literature, most of these works are based on testimonial and circumstantial evidences relating to management of architectural education only. The aim of this paper is to investigate the relationship between entry qualifications and the performance of architecture students in Nigerian Polytechnics with a view to determining the relevance of current admission policy to architectural education in Nigeria. Data were obtained from official records in the Department of Architecture in four randomly selected polytechnics in the southwestern part of Nigeria. Pearson Product Moment Corretation （r） was used to test the hypotheses. Findings reveal weak relationship between the two variables （physics and mathematics）. This is contrary to the expectations of most schotars and policy makers who opine that studentst proficiency in these subjects would enhance their performance at higher LeveLs. The paper traces the contradiction to the poor handling of public examinations and misconception of architecture as being pure science. It holds that if these requirements are still relied upon for the admission of students into schools of architecture, wrong candidates wouldcontinue to gain entry into the profession. The paper concludes by recommending certain measures that are capable of reversing the trend.

关键词： Academic perfor-mance Admission criteria Architecture Arts Education Science

SMALLEST g-SUPERSOLUTION WITH CONSTRAINT

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Applied Mathematics(A Journal of Chinese Universities) 2000年第3期15卷 289-296页

作者： Lin QingquanSchool of Mathematics and System Science,Shandong Univ.,Jinan 2 50 1 0 0 School of Mathematics and System Science Shandong Univ. Jinan

In this paper the existence and uniqueness of the smallest g-supersolution for BSDE is discussed in the case without Lipschitz condition imposing on both constraint function and drift coefficient in the different method from the one with Lipschitz *** by considering (ξ,g) as a parameter of BSDE,and ( ξ α,g α) as a class of parameters for BSDE,where α belongs to a set A,for every α ∈A there exists a pair of solution { Y α,Z α } for the BSDE,the properties of sup α ∈A{ Y α } which is also a solution for some BSDE is *** result may be used to discuss optimal problems with recursive utility.

关键词： Backward stochastic differential equation comparison theorem constraint Lipschitz condition.