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A new three-noded C1 beam finite element is derived for the analysis of sandwich beams. The formulation includes transverse shear and warping due to torsion. It also accounts for the interlaminar continuity conditions at the interfaces between the layers, and the boundary conditions at the upper and lower surfaces of the beam. The transverse shear deformation is represented by a cosine function of a higher order. This allows us to avoid using shear correction factors. A warping function obtained from a three-dimensional elasticity solution is used in the present model. Since the field consistency approach is accounted for interpolating the transverse strain and torsional strain, an exact integration scheme is employed in evaluating the strain energy terms. Performance of the element is tested by comparing the present results with exact three-dimensional solu-tions available for laminates under bending, and the elasticity three-dimensional solution deduced from the de Saint-Venant solution including both torsion with warping and bending. In addition, three-dimensional solid finite elements using 27 noded-brick elements have been used to bring out a reference solution not available for sandwich structures having high shear modular ratio between skins and core. A detailed parametric study is carried out to show the effects of various parameters such as length-to-thickness ratio, shear modular ratio, boundary conditions, free (de Saint-Venant) and constrained torsion. Copyright © 1999 John Wiley & Sons, Ltd.

Non-tsetse transmitted animal Trypanosomoses (NTTAT) result from infection by Trypanosoma evansi, T. equiprdum, and T. vivax. The latter is present both in South America and in tsetse depopulated areas of Africa. Since the inception of the OIE group, numerous studies have been carried out to result in a better understanding of this infection and hope for immunological control.

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The authors study the shape optimization of a complex cracked shell under complex criteria. The shell is one of various cases of a turboshaft, and optimization criteria are associated to the cost, the technology, and above all the working conditions for the turboshaft. The optimization criteria involved are of course the weight of the structure, but also the plastic instability and critical stress intensity factor. All computations have been made with the Ansys finite element program in which an optimization module exists.

An arbitrary Lagrangian-Eulerian model is described for the prediction of metal flow in a steady-state forming process. The formulation is shown to be capable of dealing with free surface and boundary friction; the coupling with thermal effects is also considered. The numerical techniques are based on the finite elements for spatial discretization of the momentum equation and on an explicit integration scheme for discretization relative to time. The mass and energy equations are integrated by a finite-volume method. Details on the application to an orthogonal cutting process are given in the final Section of the paper.

This paper presents a new 32-degree-of-freedom finite element of multilayered composite, moderately thick, shallow shells. The element is a four-node C 1 rectangular element and is built from standard interpolations but with a new kind of kinematics which allows us to exactly ensure the continuity conditions for displacements and stresses at the interfaces between the layers and the boundary conditions at the upper and lower surfaces of the shell

In France, a national surveillance plan to monitor congenital Schmallenberg virus (SBV) outbreaks was set up in January 2012, and has shown that SBV had become widespread throughout the country since mid-2011. However, the number of SBV-infected farms cannot accurately be estimated through congenital SBV reporting alone. Therefore, GDS France (National Animal Health Farmers' Organization) conducted serological investigations in cattle and sheep holdings in several departments in spring 2012 to assess SBV exposure in 2011. A serological study was also conducted in the department of Saône-et-Loire (southern Burgundy) to establish an accurate local overview of circulation of virus in 2011 among cattle. The study was conducted following guidelines elaborated by the French Platform for animal health surveillance. Results indicated differences in within-herd seroprevalence between cattle herds and sheep herds in departments where outbreaks of congenital SBV were reported in early 2012 and a great heterogeneity in seroprevalence between areas (even between areas geographically close to each other). In departments which had been severely affected in early 2012, the overall impact of SBV infection in cattle herds during the 2012-2013 calving season will probably be low. On the other hand, given the low proportion of immunised ewes in sheep SBV outbreaks, sheep flocks which were already affected in early 2012 may once again face congenital cases of SBV.

Schmallenberg virus (SBV) infection is an emerging livestock disease caused by a novel Orthobunyavirus which was first identified in Germany in November 2011. Non-specific clinical signs such as fever, decreased milk production and diarrhoea are associated with the acute infection in cattle, while late abortions and birth defects in newborns can be associated with the infection of pregnant cows, ewes and goats (Hoffmann and others 2012, Van den Brom and others 2012). As of March 30, 2012, since the first identification of congenital forms of SBV virus infection in The Netherlands in December 2011, about 3000 confirmed outbreaks have been reported in eight European countries (Belgium, France, Germany, Italy, Luxembourg, The Netherlands, Spain, UK) (French National Surveillance Platform for Animal Health 2012). However, little is known about SBV virus infection, especially with regard to its clinical impact in the affected herds. SBV emergence is closely monitored in France. Farmers are urged to contact their veterinarian when encountering cases of ruminant neonates or fetuses stillborn, malformed or showing nervous disorders. A brain sample is collected on any newborn suspected of congenital SBV until a first confirmation of the infection is obtained for the herd. An SBV diagnostic test is performed in state diagnostic laboratories, using real-time quantitative reverse transcription PCR (RT-qPCR). The first cases of SBV virus infection were …