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We consider nonlinear shape effects appearing in the lumped electromechanical model of a bimorph piezoelectric bridge structure due to the interaction between the electromechanical constitutive model and the geometry of the structure. At finite proof-mass displacement and electrode voltage, the shape of the beams is no longer given by Euler-Bernoulli theory which implies that shape effects enter in both the electrical and mechanical domains and in the coupling between them. Accounting for such effects is important for the accurate modelling of, e.g., piezoelectrical energy harvesters and actuators in the regime of large deflections and voltages. We present a general method, based on a variational approach minimizing the Gibbs enthalpy of the system, for computing corrections to the nominal shape function and the associated corrections to the lumped model. The lowest order correction is derived explicitly and is shown to produce significant improvements in model accuracy, both in terms of the Gibbs enthalpy and the shape function itself, over a large range of displacements and voltages. Furthermore, we validate the theoretical model using large deflection finite element simulations of the bridge structure and conclude that the lowest order correction substantially improve the model, obtaining a level of accuracy expected to be sufficient for most applications. Finally, we derive the equations of motion for the lowest order corrected model and show how the coupling between the electromechanical properties and the geometry of the bridge structure introduces nonlinear interaction terms.

Different microelectromechanical system (MEMS) packaging strategies towards high packaging density of MEMS devices and lower expenditure exist both in the market and in research. For example, electrical interconnections and low stress wafer level packaging are essential for improving device performance. Hybrid integration of low temperature co-fired ceramics (LTCC) with Si can be a way for an easier packaging system with integrated electrical interconnection, and as well towards lower costs. Our research on LTCC-Si integration is reported in this paper.

Three-axis accelerometers based on four separate seismic masses, each one suspended on a slanted beam, have previously been shown to have identical resolution and frequency responses in all directions. Here, a new and in-depth model of such accelerometers is presented. The theoretical model incorporates non-ideal effects such as the finite aspect ratio of the beam and the frequency-dependent squeezed gas-film damping. Sensitivity, resolution, transverse sensitivity and process errors are discussed. Prototype devices have been fabricated in a straightforward silicon process.

Three-axis accelerometers based on four separate seismic masses, each one suspended on a slanted beam, have previously been theoretically shown to have identical resolution and frequency responses in all directions. New simulation and models for this type of accelerometers have been developed and these are verified with measurements of the g-vector, shaker measurements and optical modal analysis. The measurements show good agreement with the new models. The results also show that the slanted-beam topology is a promising alternative for future three-axis accelerometer designs.

We report on nine unrelated children fitting a diagnosis of Carey–Fineman–Ziter syndrome (CFZS). All children presented with Möbius sequence, Pierre Robin complex (6/9) or micrognathia, and hypotonia. Some had primary hypoventilation, delayed development, and acral anomalies. The neuropathological investigations performed in two patients showed a combination of dysplastic lesions (neuronal heterotopias) and encephaloclastic changes consisting of small foci of necrosis with microcalcifications. The mother of a third child had severe trauma during her 2nd month of pregnancy. Based on a review of the literature on MS and CFZS, we suggest designating as “Robin–Möbius phenotype” a distinct clinical variant of MS with extensive brainstem involvement, Robin complex, hypotonia without specific muscle disorder, clubfeet and variable acral anomalies. This condition appears to bear a higher risk of mental handicap and perhaps a higher recurrence risk than “common” MS. Neuropathology and neuroimaging are suggestive, at least in some cases, of a vascular disruption, which could be exogenous, or secondary to a genetic predisposition. Etiologic heterogeneity seems likely and, in that respect, the original CFZS family could represent a private syndrome fitting on the “Robin–Möbius” spectrum. Despite the existence of two familial reports, recurrence risk is probably much lower than 25%, although exact figures cannot be extracted from the available literature. © 2004 Wiley-Liss, Inc.

BackgroundAcute lymphoblastic leukaemia (ALL) is the most common malignancy during childhood and has a high cure rate. On the other hand, the prognosis of acute myeloid leukaemia (AML) remains poor despite progress achieved over the past decade.AimCorrelation between molecular genetics and treatment response of paediatric leukaemia patientsMethods49 patients diagnosed with acute leukaemia in the OncoHematology Paediatric Unit between January 2015 and December 2016 were analysed for bone marrow gene alterations. For ALL patients the mutational status of the ABL-BCR, MLL-AF4, TEL-AML1, E2A-PBX genes was assessed and for AML patients, the mutational status of AML-ETO, PML-RARa, FLT3, NPM1 fusion genes.Results7 of 31 ALL patients had TEL-AML fusion present and one of them showed E2A-PBX fusion present. The other genes tested came out absent. All patients were submitted to protocol ALL-IC BFM 2002 treatment. On day 33 of treatment complete remission was confirmed for all of them. One patient had an early relapse but with no modification in gene rearrangement. Out of 18 AML patients, 2 had present PML-RARa mutation, while another 2 had present FLT3; in addition, one of them also tested positive for NPM1 mutation. All patients received treatment according to AIEOP AML protocol. We lost two patients in the early stage of the treatment, one of them with both FTL3 and NPM1 mutations present.ConclusionsThis study is a step towards the complete and modern diagnosis of children with acute leukaemia, in our centre. Different oncogenic profiles can be related to different therapeutic responses, which means that targeted therapeutic approaches are necessary.