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THE GLOBAL dUFORT-FRANKEL dIFFERENCE APPROXIMATION FOR NONLINEAR REACTION-dIFFUSION EQUATIONS

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Journal of Computational Mathematics 1998年第3期16卷 275-288页

作者： Lu, BN Wan, gh Guo, BL Xiangtan Univ Inst Computat & Appl Math Xiangtan 411105 Peoples R China Inst Appl Phys & Computat Math Lab Computat Phys Beijing 100088 Peoples R China Shaanzi Normal Univ Dept Math Xian 710062 Peoples R China Inst Appl Phys & Computat Math Ctr Nonlinear Studies Beijing 100088 Peoples R China

In this paper, the initial value problem of nonlinear reaction-diffusion equation is considered. The dufort-Frankel finite difference approximation for the long time scheme is given for the d-dimensional reaction-diffusion equation with the two different cases. The global solution and global attractor are discussed for the dufort-Frankel scheme. Moreover properties of the solution are studied. The error estimate is presented in a finite time region and in the global time region for some special cases. Finally the numerical results for the equation are investigated for Allen-Cahn equation and some other equations and the homoclinic orbit is simulated numerically.

关键词： global dufort-Frankel method reaction-diffusion equation global attractor error estimate numerical experiments

A new route to the synthesis of thieno[2,3-d]pyrimidin-4(3H)-one derivatives catalyzed by 12-tungstophosphoric acid (H_3PW_(12)O_(40))

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Chinese Chemical Letters 2007年第12期18卷 1483-1486页

作者： A.davoodnia M.Bakavoli gh.Barakouhi N.Tavakoli-Hoseini department of Chemistry School of SciencesIslamic Azad UniversityMashhad 91735-413Iran

Heteropoly acid H3PW12040 （PW） has been used as an effective catalyst for the synthesis of thieno[2,3-d]pyrimidin-4（3H）-one derivatives. The present methodology offers several advantages, such as high yields, shor... 详细信息

关键词： Thieno[2,3-d]pyrimidin-4(3H)-one Heteropoly acid 12-Tungstophosphoric acid Orthoesters

GdNF cdNA-engineered NIH 3T3 cells protect primary dopaminergic neurons

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Chinese Science Bulletin 1997年第22期42卷 1921-1925页

作者： Ma, dd Wang, XM Jing, XJ Wang, J Xiong, L Song, H Wan, Y Xu, gh Sun, QL Cai, d Wang, XH Han, JS Beijing Med Univ Neurosci Res Ctr Beijing 100083 Peoples R China

IN vitro and in vivo experiments show the protective effects of glial cell line-derived neu-rotrophic factor (GdNF) on dopaminergic (dA) neurons are potent and relatively specif-ic. However, GdNF protein is not small ... 详细信息

关键词： GdNF Parkinson’s disease engineering cells dopaminergic neurons.

Influence of Oscillation Frequency of a Sieve on the Screening Process for a Conical Sieve with Oscillatory Circular Motion

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Journal of Agricultural Science and Technology(B) 2011年第8期1卷 1224-1231页

作者： gh. Voicu d. Stoica N. Ungureanu Faculty of Biotechnical Systems Engineering ＂Politehniea＂ University of Bucharest Splaiul Independentei 313 Bucharest 060042Romania

Removal of foreign bodies from seed mixtures, or their calibration for use as planting material, as well as fraction classification of granular materials requires screening surfaces with vibratory motion. This paper presents some aspects on the working process of a sieve, made of perforated sheet and having an outer conical surface with oscillatory circular motion （alternative） on the horizontal. Results are presented for some experimental researches on the movement of material on the sieve, for various kinematical parameters of the sieve （amplitude and oscillation frequency）. A conical sieve, suspended at the upper and lower in three points, was tested for screening of rapeseeds in order to estimate the influence of oscillation frequency on the screening process. Curves were drawn for separation intensity on the sieve generating line, and by regression analysis with normal distribution law were determined the equation coefficients and the correlation with experimental data. Movement of material on the sieve and its working process, in general, was appreciated by means of the peak position of distribution curve depending on the oscillation frequency of the sieve, considering that the normal distribution law correlates very well the data obtained by experiments.

关键词： Grain sieving conical sieve oscillatory circular motion oscillation frequency normal distribution law.

Meeting report:a hard look at the state of enamel research

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International Journal of Oral Science 2017年第4期9卷 193-199页

作者： ophir d klein olivier duverger wendy shaw rodrigo s lacruz derk joester janet moradian-oldak megan k pugach j timothy wright sarah e millar ashok b kulkarni john d bartlett thomas gh diekwisch pamela den besten james p simmer program in craniofacial biology and department of orofacial sciences university of californiasan franciscoSan FranciscoUSA department of pediatrics and institute for human genetics university of californiasan franciscoSan FranciscoUSA laboratory of skin biology national institute of arthritis and muscular and skin diseasesnational institutes of healthBethesdaUSA physical science division pacific northwest national laboratoriesRichlandUSA department of basic science and craniofacial biology new york university college of dentistryNewYorkUSA department of materials science and engineering northwestern universityevanstonusaEvanstonUSA center for craniofacial molecular biology herman ostrow school of dentistryuniversity of southern californiaLos AngelesUSA the forsyth institute CambridgeUSA department of developmental biology harvard school of dental medicineBostonUSA department of pediatric dentistry university of north caroline school of dentistryChapel HillUSA departments of dermatology and cel&developmental biology perelman school of medicineand department of anatomy&cell biologyschool of dental medicineuniversity of pennsylvaniaPhiladelphiaUSA functional genomics section national institute of dental and craniofacial researchBethesdaUSA division of biosciences ohio state universitycollege of dentistryColumbusUSA department of periodontics and center for craniofacial research and diagnosis texas a&m university college of dentistryDallasUSA center for children’s oral health research and department of orofacial sciences university of californiasan franciscoSan FranciscoUSA biologic and materials sciences and division of prosthodontics university of michiganAnn ArborUSA

The Encouraging Novel Amelogenesis Models and Ex vivo cell Lines （ENAMEL） development workshop was held on 23 June 2017 at the Bethesda headquarters of the National institute of dental and Craniofacial Research （NIdCR）. discussion topics included model organisms, stem cells/cell lines, and tissues/3d cell culture/organoids. Scientists from a number of disciplines, representing institutions from across the United States, gathered to discuss advances in our understanding of enamel, as well as future directions for the field.

关键词： enamel mineralized tissue mineralization ameloblast stem cell

Situation and Strategies of the Maternal and Infant Health in Tunisia

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Journal of Reproduction and Contraception 2005年第1期16卷 57-64页

作者： Gueddana N ghérissi A Esseghari R General director. National Board for Family and Population. Tunisia Unit of research on evaluation in health. département de Médecine Communautaire B. Facultéde Médecìnede Tunis Tunisia International Training and Research Centre on Reproductive Health. National Board for Family and Population Tunisia

This paper presents then makes a retrospective and descriptive evaluation of the Tunisian strategy implemented to reduce maternal and infant mortality and morbidity. The objectives of this bibliography work are to make a diagnosis of the situation of the maternal and infant mortality and morbidity, to develop the philosophy and the orientations of the strategic axis and to underline the keys of the success as well as the limits of the strategy.

关键词： maternal mortality neonatal morbidity monitoring maternal deaths causes of maternal deaths

THE ENVIRONMENTAL IMPACT OF THE COAL EXTRACTION ANd ENERGY INdUSTRY IN MIddLE JIU VALLEY (ROMANIA)

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THE ENVIRONMENTAL IMPACT OF THE COAL EXTRACTION AND ENERGY I...

Special Finite Element for the Study of Highly Flexible Mechanisms

第三世界生态高峰会

作者： M.Corneanu G.Corneanu L.Cojocaru d.Radutoiu gh.Gamaneci IUSAMV Timisoara Genetics Lab. C.Aradului119 300645.Timisoara. University of Craiova. Environmental Protection Agencv dolj University of Craiova. Brancusi University Tg.Jiu.Romania

*** extraction and energy industries,contribute at the dislocation of a great amount of soil,as well as at the artificial modifications of the soil,through forming of sterile and ash waste dump,that present a high content in heavy metals and radionuclides,a permanent pollution *** *** Jiu river valley is a well known coal basin in active *** the surface exploitations a Thermo-Electric Power Plant(TEPP)-Rovinari-is surrounded by ash waste dumps of different *** aim of this paper was to study the pollution impact,with heavy metals and radionuclides from ash waste dumps,on vegetation in nearby village Rosia de Jiu and on the other hand the natural and artificial recovery phenomenon on the ash and sterile dump of different *** stations from which were draw samples soil and plants-belonging to different area surrounding TEPP Rovinari and surface coal exploitation—ash waste dump(over 5 years old),sterile waste dump(25-30 years;5 years old), wasteland(excavated waste 20 years old),cultivated lands in nearby village Rosia de *** content in radionuclides was established by duggau method,in conformity with IAEA TECdOC 1092 directives. In all stations were observed the vegetal associations and the status of the plantations *** investigations were performed in Allium cepa and ***,halwested from different locations in the village Rosia de Jiu,in order to determine the amount and type of chromosomal aberrations,induced by the *** and *** highest amount in radionuclides in soil,as well as in plants was registered in samples harvested from young age ash waste dump and sterile waste *** radioactivity for the most of the radionuclides was higher thal natural average in U-235,Ra-226, Pb-214,Bi-214,Bi-212,*** a relatively high amount in radinuclides was found in nearby village *** natural recovery process on ash waste dump started with phyto

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Special Finite Element for the Study of Highly Flexible Mech...

Functional MRI and MR Spectroscopy Utilization in Jeddah Hospitals

第十一届IFTOMM世界大会

作者： Mircea gh. Munteanu André Barraco Transilvania University of Bra■ov Romania LMSP UMR 8106 CNRS ENSAM ParisFrance

＜正＞A special 3d finite element having four degrees of freedom per node, the nodal Euler-Rodrigues parameters, is described in this work. This finite element may be used for the static and dynamic study of highly deformable 3d mechanisms. The stiffness and mass matrices are expressed only in the nodal Euler-Rodrigues parameters and therefore the unknowns of the problem are these nodal parameters for the nodes of the whole finite element assembly. The most important aspect of the proposed approach is that the exact equations, written for the deformed configuration, are solved. So, a very accurate and fast convergent method results. This method is a non-incremental one, which means that in static analysis the accuracy does not depend on the number or of the load steps, in many cases only one load step is sufficient.

关键词： Finite element method deformable mechanisms Large motion dynamic analysis Euler-Rodriques parameters

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Open Journal of Medical Imaging 2015年第3期5卷 165-173页

作者： Lamis K. Jada Nabeel Mishah Khalid gh. Alsafi Sarah Hagi Mawya A. Khafaji Hanan Y. Abbas Saddig d. Jastaniah department of diagnostic Radiology Faculty of Applied Medical Sciences King Abdulaziz University Jeddah KSA Radiology department King Abdulaziz University Hospital Jeddah KSA department of Radiology School of Medicine King Abdulaziz University Jeddah KSA

Functional magnetic resonance imaging “fMRI” and magnetic resonance spectroscopy “MRS” are two crucial milestones that were introduced apart from one another into brain imaging and their implementation in major local cities is eventual step. Thus, the purpose of this study was to compare those techniques in terms of their clinical utilization in patient care delivery among the major governmental and private hospitals within Jeddah city. The study initially included eighteen hospitals to identify whether they were utilizing fMRI and MRS in their clinical practice. Out of the 18 hospitals under study only one hospital (5.6%) had both fMRI and MRS software;7 (38.9%) had MRS but not fMRI;4 (22.2%) did not have fMRI or MRS;and 6 (33.3%) hospitals had no MRI machine at all. Out of the eight hospitals applying MRS with one being excluded, the starting date of application was 2002 in 4 (57.1%) hospitals, 2004 in 1 (14.3%) hospital, and 2006 in 2 (28.6%) hospitals. The frequency of doing MRS was once a week in 2 (28.6%) hospitals, 2-3 cases/week in 3 (42.9%) hospitals, 5-10 cases/week in 1 (14.3%) hospital, and once every 6 months in 1 (14.3%) hospital. On the other hand, fMRI was applied only by one hospital starting in 2000 and was soon dismissed due to its time consumption and the inability of patients to accurately follow given instructions. It was concluded that MRS was more widely utilized compared to fMRI. Later on, a follow-up survey in the year of 2014 demonstrated that MRS has started to become a standard service in most hospitals whereas fMRI was still being unrecognized.

关键词： Brain fMRI Activation MRS Metabolites