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AEI/FEDER UE (DPI2017-90147-R).

Cincuenta años después de que el primer ser humano aterrizara en la Luna, la humanidad ha comenzado a planificar los próximos pasos para las misiones de exploración espacial tripuladas. Cuando el tiempo necesario para regresar a la Tierra supera los 400 - 500 días (como en los viajes a Marte), el nivel de independencia que debe poseer la tripulación aumenta considerablemente. Para garantizar la supervivencia y las buenas condiciones de vida de estos futuros exploradores, se deben realizar nuevos desarrollos en cuanto a infraestructuras y recursos médicos..

Tumors with anisotropy in their structural properties experience unpredictable and asymmetric growth along certain directions that can vary over time during the tumor progression. An early recognition of such anisotropy could provide information about their malignity, facilitating early diagnostics/prognostic. However, it is difficult to be observed by classic echography. Diverse studies of the literature show 3D images of elastic properties in media with anisotropy in a certain direction, but are transversely isotropic. However, for highly anisotropy media this assumption is no longer valid and requires specific measurements of shear velocities in the 3D directions. These media with 21 independent elastic material parameters and no symmetry plane. Techniques using ultrafast focused sound scanners present difficulties in covering immediate regions around the focused area and specific information for different incident beam orientations to obtain complete 3D spatial information, which is relevant in these types of media without planes of symmetry. It is the case of malignant tumors. The current paper presents a flexible spatial study of mechanical displacements induced in highly anisotropic soft media by low frequency shaker (including printed inorganic, pseudo-organic grids and cow fiber tissues respectively). Homogeneous and heterogeneous media without planes of symmetry have been tested in the experiments by using speckle ultrasonic interferometry. Velocities associated to the induced low frequency-mechanical displacements have been analyzed at a point of interest within the sample from different angles of propagation, covering a 3D angular space. These measurements show a high spatial-dependence of results, demonstrating the relevance of making spatial angular scans to derive parameters related to the anisotropy. This technique allows detection of anisotropies in small areas of analysis, even if they are weak, AEI/FEDER, UE DPI2017-90147-R

Additive manufacturing (AM) techniques are becoming the approaches of choice for the construction of scaffolds in tissue engineering. However, the development of 3D printing in this field brings unique challenges, which must be accounted for in the design of experiments. The common printing process parameters must be considered as important factors in the design and quality of final 3D-printed products. In this work, we study the influence of some parameters in the design and fabrication of PCL scaffolds, such as the number and orientation of layers, but also others of &ldquo, hidden&rdquo, importance, such as the cooling down rate while printing, or the position of the starting point in each layer. These factors can have an important impact oin the final porosity and mechanical performance of the scaffolds. A pure polycaprolactone filament was used. Three different configurations were selected for the design of the internal structure of the scaffolds: a solid one with alternate layers (solid) (0&deg, 90&deg, ), a porous one with 30% infill and alternate layers (ALT) (0&deg, ) and a non-alternated configuration consisting in printing three piled layers before changing the orientation (n-ALT) (0&deg, 0&deg, ). The nozzle temperature was set to 172 &deg, C for printing and the build plate to 40 &deg, C. Strand diameters of 361 &plusmn, 26 &micro, m for room temperature cooling down and of 290 &plusmn, 30 &micro, m for forced cooling down, were obtained. A compression elastic modulus of 2.12 &plusmn, 0.31 MPa for n-ALT and 8.58 &plusmn, 0.14 MPa for ALT scaffolds were obtained. The cooling down rate has been observed as an important parameter for the final characteristics of the scaffold.