Modelling of the radiative properties of an opaque porous ceramic layer

Solid Oxide Fuel Cells (SOFCs) operate at temperatures above 1,100 K where radiation effects can be significant. Therefore, an accurate thermal model of an SOFC requires the inclusion of the contribution of thermal radiation. This implies that the thermal radiative properties of the oxide ceramics used in the design of SOFCs must be known. However, little information can be found in the literature concerning their operating temperatures. On the other hand, several types of ceramics with different chemical compositions and microstructures for designing efficient cells are now being tested. This is a situation where the use of a numerical tool making possible the prediction of the thermal radiative properties of SOFC materials, whatever their chemical composition and microstructure are, may be a decisive help. Using this method, first attempts to predict the radiative properties of a lanthanum nickelate porous layer deposited onto an yttria stabilized zirconium substrate can be reported

Cost-effectiveness of rotavirus vaccination in the Netherlands; the results of a consensus model

Contains fulltext : 96770.pdf (publisher's version ) (Open Access)BACKGROUND: Each year rotavirus gastroenteritis results in thousands of paediatric hospitalisations and primary care visits in the Netherlands. While two vaccines against rotavirus are registered, routine immunisation of infants has not yet been implemented. Existing cost-effectiveness studies showed inconsistent results for these vaccines because of lack of consensus on the impact. We aimed to investigate which factors had a major impact on cost-effectiveness and were primarily responsible for the large differences in previously estimated cost-effectiveness ratios. METHODS: Based on updated data on health outcomes and cost estimates, we re-assessed the cost-effectiveness of routine paediatric rotavirus vaccination within the National Immunization Program for the Netherlands. Two consensus meetings were organised with national and international experts in the field to achieve consensus and resolve potential controversies. RESULTS: It was estimated that rotavirus vaccination in the Netherlands could avert 34,214 cases of rotavirus gastroenteritis in children aged less than 5 years. Notably, 2,779 hospitalisations were averted of which 315 were extensions of existing hospital stays due to nosocomial rotavirus infection. With a threshold varying from 20K euro - 50K euro per QALY and according to the base-case scenario, the full vaccination costs per child leading to cost-effectiveness was euro 57.76 -euro 77.71. Results were sensitive to the inclusion of potential vaccine induced herd protection, QALY losses and number of deaths associated with rotavirus gastroenteritis. CONCLUSIONS: Our economic analysis indicates that inclusion of rotavirus vaccination in the Dutch National Immunization Program might be cost-effective depending on the cost of the vaccine and the impact of rotavirus gastroenteritis on children's quality of life

A hysteresis model with dipole interaction: one more devil-staircase

Magnetic properties of 2D systems of magnetic nanoobjects (2D regular lattices of the magnetic nanoparticles or magnetic nanostripes) are considered. The analytical calculation of the hysteresis curve of the system with interaction between nanoobjects is provided. It is shown that during the magnetization reversal system passes through a number of metastable states. The kinetic problem of the magnetization reversal was solved for three models. The following results have been obtained. 1) For 1D system (T=0) with the long-range interaction with the energy proportional to $r^{-p}$, the staircase-like shape of the magnetization curve has self-similar character. The nature of the steps is determined by interplay of the interparticle interaction and coercivity of the single nanoparticle. 2) The influence of the thermal fluctuations on the kinetic process was examined in the framework of the nearest-neighbor interaction model. The thermal fluctuations lead to the additional splitting of the steps on the magnetization curve. 3) The magnetization curve for system with interaction and coercivity dispersion was calculated in mean field approximation. The simple method to experimentally distinguish the influence of interaction and coercivity dispersion on the magnetization curve is suggested.Comment: 22 pages, 8 figure

Universal Crossover between Efros-Shklovskii and Mott Variable-Range-Hopping Regimes

A universal scaling function, describing the crossover between the Mott and the Efros-Shklovskii hopping regimes, is derived, using the percolation picture of transport in strongly localized systems. This function is agrees very well with experimental data. Quantitative comparison with experiment allows for the possible determination of the role played by polarons in the transport.Comment: 7 pages + 1 figure, Revte