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The paper describes a method and a computer application for the computation of the velocity of acoustic waves excited in complicated multi-layered structures consisting of anisotropic piezoelectric and isotropic layers. The structure assumes to be unbounded in the lateral directions. The top and bottom layers are either semiinfinite or they contact with media such as fluids, gases or vacuum. A special homogenization technique enables to account for bristlelike layers contacting with a fluid. The program is supplied with a user friendly graphical interface and can be useful for researchers working on acoustic sensors.

The article describes an interior-point method for minimizing a smooth strictly convex function f: R n ! R, f 2 C 2 ðR n Þ, on the convex hull P of m points in R n . The algorithm uses barycentric coordinates for representing points in P and generates points in P with positive coordinates. In particular, the algorithm can be used to compute the orthogonal projection of a point x c 2 R n to P.

Nanoindentation with spherical tipped indenters provides a powerful technique to explore surface and thin film mechanical properties through the application of Hertzian contact mechanics. The full range of mechanical response can be obtained from elastic, through the yield point, to permanent deformation. In this study spherical indentation has been used for probing MBE-grown NiTiCu alloy thin films into superelasticity or stress-induced martensitic transformation. By this way, obstacles typically occurring related to the fabrication of freestanding films (film thickness < 1 µm) are avoided. The indentation measurements were performed starting from the parent austenite state. Notably, for loads as small as 0.5 mN, deformation appears to be completely reversible. As loading is increased (up to 5 mN) the indent becomes irreversible following local plastic deformation within the tip-specimen contact area. Using finite-element simulations the indentation data were converted into a stress-strain diagram aimed at simulating uniaxial tension load. Therefrom, the superelastic strain is estimated to be around 3%.

The article deals with an idea of exploiting an acoustic shear wave biosensor for investigating the glycocalyx, a polysaccharide polymer molecule layer on the endothelium of blood vessels that, according to recent studies, plays an important role in protecting against diseases. To test this idea, a mathematical model of an acoustic shear wave sensor and corresponding software developed earlier for proteomic applications are used. In this case, the glycocalyx is treated as a layer homogenized over the thin polymer “villi”. Its material characteristics depend on the density, thickness, and length of the villi and on the viscous properties of the surrounding liquid (blood plasma). It is proved that the model used has a good sensitivity to the above parameters of the villi and blood plasma. Numerical experiments performed using real data collected retrospectively from premature infants show that the use of acoustic shear wave sensors may be a promising approach to investigate properties of glycocalyx-like structures and their role in prematurity.