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排序方式: 共有111条查询结果,搜索用时 15 毫秒
1.
Krawczak M Nikolaus S von Eberstein H Croucher PJ El Mokhtari NE Schreiber S 《Community genetics》2006,9(1):55-61
OBJECTIVE: Patient samples used for mapping complex human disease genes are unlikely to be representative of the phenotype spectrum of the respective population as a whole. On the other hand, most ongoing prospective studies are probably too small for evaluating polygenic disease markers. DESIGN: Precise estimates of population-specific genotypic risks can be obtained efficiently through the complete ascertainment of patients in a geographically confined area. The PopGen project uses the most northern part of Germany as a target region for such a pursuit. RESULTS: PopGen currently pursues recruitment, sampling and processing activities in close collaboration with a multitude of clinical partners, covering cardiovascular, neuropsychiatric and environmental diseases. CONCLUSION: PopGen has successfully established itself as a large-scale genetic epidemiological project of international recognition. 相似文献
2.
A general procedure has been developed for the simulation of charged liquid and electrostatically atomized sprays. The procedure follows a Lagrangian approach for simulation of spray droplets and a Eulerian approach for gas‐phase variables, including the electric field generated by the charge presence on droplets. Validation of the procedure was examined through simulations of previously published charged spray experiments. Results showed that for the specification of initial droplet charge, modelling the droplet charge–diameter relationship through a scaling law is as reliable a method as using a directly obtained charge–diameter relationship from experimental measurements. The normalized root‐mean‐square errors for sprays using the two methods were shown to be within 12% of one another, for the prediction of spatially averaged profiles of mean droplet diameters, mean axial velocities and mean radial droplet velocities. Results showed that the general spatial characteristics and dynamics of a charged liquid spray can successfully be reproduced, including the axial and radial dispersal pattern of droplets and the distribution of mean droplet diameters throughout the spray plume. For all sprays with droplet charges defined through a scaling law relationship, the normalized root‐mean‐square errors range from 9.0% to 31.6% for mean droplet diameters, 10.4% to 67.9% for mean axial droplet velocities and 16.8% to 38.6% for mean radial droplet velocities. Lastly, we present a brief set of general recommendations for simulating electrostatically atomized dielectric liquid sprays.Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
3.
BedrʼEddine Ainseba Mostafa Bendahmane Ricardo Ruiz-Baier 《Journal of Mathematical Analysis and Applications》2012,388(1):231-247
In the present paper, an optimal control problem constrained by the tridomain equations in electrocardiology is investigated. The state equations consisting in a coupled reaction–diffusion system modeling the propagation of the intracellular and extracellular electrical potentials, and ionic currents, are extended to further consider the effect of an external bathing medium. The existence and uniqueness of solution for the tridomain problem and the related control problem is assessed, and the primal and dual problems are discretized using a finite volume method which is proved to converge to the corresponding weak solution. In order to illustrate the control of the electrophysiological dynamics, we present some preliminary numerical experiments using an efficient implementation of the proposed scheme. 相似文献
4.
Nasser Eddine Mouhoub Abdelhamid Benhocine Hocine Belouadah 《Applied Mathematical Modelling》2011,35(9):4575-4588
A project is an enterprise consisting of several activities which are to be carried out in some specific order. The activities and the order in which they need to be carried out can be represented by a PERT network. The PERT technique is a traditional, well-known approach to the expert of project management. When networks are used, it often becomes necessary to draw dummy activities. Since the computation of project completion time is proportional to the number of arcs, including dummy arcs, it is desirable to draw a network with as few dummy activities as possible.In this paper, we propose a new method for constructing, for a given project scheduling problem, a PERT network having as small as possible the number of dummy arcs by using some results on line graphs. This algorithm deals with the existence of transitive arcs. The paper contains illustrative examples, proofs of some theoretical results as well as a comparative study with a similar algorithm known in the literature. Computational results showed the superiority of our algorithm. 相似文献
5.
6.
Kherroub Djamal Eddine Belbachir Mohammed Lamouri Saad 《Research on Chemical Intermediates》2017,43(10):5841-5856
Research on Chemical Intermediates - A new green technique to synthesize polysiloxane-type polymers is suggested based on use of chemically modified clay (Maghnite-H+) as heterogeneous,... 相似文献
7.
Mokhtar Benziane Kamel Khimeche Abdellah Dahmani Sawsen Nezar Djalal Trache 《Journal of Thermal Analysis and Calorimetry》2013,112(1):229-235
Solid–liquid equilibria for three binary mixtures of {n-eicosane (1) + methyl palmitate (2)}, {n-tetracosane (1) + methyl stearate (2)} and {n-octacosane (1) + methyl stearate (2)} were measured using differential scanning calorimeter. Simple eutectic behaviours for these systems were observed. The experimental results were correlated by means of the modified UNIFAC (Larsen and Gmehling versions), UNIQUAC and ideal models. The root-mean-square deviations of the solubility temperatures for all measured data vary from 0.21 K (for UNIQUAC model) to 1.07 K (for Ideal model) and depend on the particular model used. The best solubility correlation was obtained with UNIQUAC model. 相似文献
8.
Djalal Trache Kamel Khimeche Mokhtar Benziane Abdallah Dahmani 《Journal of Thermal Analysis and Calorimetry》2013,112(1):215-222
Solid–liquid equilibria for three binary mixtures of N-(2-acetoxyethyl)-p-nitroaniline (1) + 2-nitrodiphenylamine (2), N-(2-acetoxyethyl)-p-nitroaniline (1) + ethyl centralite (2) and N-(2-acetoxyethyl)-p-nitroaniline (1) + methyl centralite (2) have been determined experimentally using differential scanning calorimeter (DSC). Simple eutectic behaviours for these systems have been observed. The experimental results have been correlated by means of NRTL and UNIQUAC equations. The root-mean-square deviations of the solubility temperatures for all measured data vary from 0.61 to 3.32 K and depend on the particular model used. The best solubility correlation has been obtained with the UNIQUAC model. 相似文献
9.
Radia Bouasla Hadjira Berredjem Malika Berredjem Malika Ibrahim‐Oualid Assia Allaoui Marc Lecouvey Nour‐Eddine Aouf 《Journal of heterocyclic chemistry》2013,50(6):1328-1332
A new series of chiral 5‐substituted bis‐oxazolidinones containing an acylsulfonamide moiety has been synthesized starting from chlorosulfonyl isocyanate, (l )‐ethyl lactate, and oxazolidin‐2‐ones. All the reactions were conducted at ambient temperature, and the N‐acylsulfonamide bis‐oxazolidin‐2‐ones were obtained with high yields within 2 h. Some of the newly synthesized compounds were evaluated in vitro against the virulent strain RH of Toxoplasma gondii and the human lymphocytes, and showed promising results. 相似文献
10.
Liliane Bokobza Mostafa Rahmani Colette Belin Jean‐Luc Bruneel Nour‐Eddine El Bounia 《Journal of Polymer Science.Polymer Physics》2008,46(18):1939-1951
The reinforcement of a styrene‐butadiene rubber (SBR) by single fillers—carbon black (CB) or multiwall carbon nanotubes (MWNTs)—or by mixtures of CB and MWNTs, is investigated. The morphologies, mechanical and electrical properties of the composites, are analyzed. A significant improvement in the tensile properties is observed for samples containing a dual phase. Using atomic force (AFM) and transmission electron (TEM) microscopies, we demonstrate that the double loading improves the dispersion of the nanotubes in SBR. Electrical measurements show lower resistivity and a lower percolation threshhold for composites containing blends of fillers, which provides further evidence of better dispersion. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 46: 1939–1951, 2008 相似文献