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Climate change has highlighted the need to promote renewable energies. The offshore wind industry is growing exponentially because of some political strategies supported by various organizations, such as the European Union. The implementation of these strategies is commonly associated with significant investments, public acceptance, or achieving better installations and greater cumulative capacities. To ensure that offshore renewable energy projects could reach their ambitious targets, this study promotes the implementation of political strategies or planning decisions using data mining techniques and analytical tools. Strategic decisions based on real data analysis could help to achieve more suitable and optimal infrastructures. The scour phenomenon jeopardizes the operability of offshore wind farms, making it necessary to study its evolution over the years. In this work, extensive research on the scour phenomenon in offshore wind farms using real data (from the Lynn and Inner Dowsing offshore wind farms located in the UK) was performed, which revealed an evident lack of consideration of this phenomenon for data-driven decision-making processes. As a novelty, this research develops a detailed geospatial analysis of data, studying the possible autocorrelation of scour data measured from each turbine between 2011 and 2015. The conclusions obtained could be used to improve future planning tasks in offshore wind farms. © 2023 by the authors.

3D bioprinting involves using bioinks that combine biological and synthetic materials. The selection of the most appropriate cell-material combination for a specific application is complex, and there is a lack of consensus on the optimal conditions required. Plasma-loaded alginate and alginate/methylcellulose (Alg/MC) inks were chosen to study their viscoelastic behaviour, degree of recovery, gelation kinetics, and cell survival after printing. Selected inks showed a shear thinning behavior from shear rates as low as 0.2 s−1, and the ink composed of 3% w/v SA and 9% w/v MC was the only one showing a successful stacking and 96% recovery capacity. A 0.5 × 106 PANC-1 cell-laden bioink was extruded with an Inkredible 3D printer (Cellink) through a D = 410 μm tip conical nozzle into 6-well culture plates. Cylindrical constructs were printed and crosslinked with CaCl2. Bioinks suffered a 1.845 Pa maximum pressure at the tip that was not deleterious for cellular viability. Cell aggregates can be appreciated for the cut total length observed in confocal microscopy, indicating a good proliferation rate at different heights of the construct, and suggesting the viability of the selected bioink PANC-1/P-Alg3/MC9 for building up three-dimensional bioprinted pancreatic tumor constructs.

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

New additive manufacturing techniques, such as melting electro-writing (MEW) or nearfield electrospinning (NFES), are now used to include microfibers inside 3D printed scaffolds as FDM printers present a limited resolution in the XY axis, not making it easy to go under 100 m without dealing with nozzle troubles. This work studies the possibility of creating reproducible microscopic internal fibers inside scaffolds printed by standard 3D printing. For this purpose, novel algorithms generating deposition routines (G-code) based on primitive geometrical figures were created by python scripts, modifying basic deposition conditions such as temperature, speed, or material flow. To evaluate the influence of these printing conditions on the creation of internal patterns at the microscopic level, an optical analysis of the printed scaffolds was carried out using a digital microscope and subsequent image analysis with ImageJ software. To conclude, the formation of heterogeneously shaped microfilaments (48 12 m, mean S.D.) was achieved in a standard FDM 3D Printer with the strategies developed in this work, and it was found that the optimum conditions for obtaining such microfibers were high speeds and a reduced extrusion multiplier.

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 “hidden” 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 , 90 ), a porous one with 30% infill and alternate layers (ALT) (0 , 90 ) and a non-alternated configuration consisting in printing three piled layers before changing the orientation (n-ALT) (0 , 0 , 0 , 90 , 90 , 90 ). The nozzle temperature was set to 172 C for printing and the build plate to 40 C. Strand diameters of 361 26 m for room temperature cooling down and of 290 30 m for forced cooling down, were obtained. A compression elastic modulus of 2.12 0.31 MPa for n-ALT and 8.58 0.14 MPa for ALT sca olds were obtained. The cooling down rate has been observed as an important parameter for the final characteristics of the scaffold.

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.., Fifty years after the first human landed on the Moon mankind has started to plan the next steps for manned space exploration missions. When the time required to return to Earth exceeds 400-500 days (as in travels to Mars), the level of independence that the crew must possess is highly increased. To ensure the survival and good living conditions of this future explorers, new developments regarding medical infrastructure and resources must becarried out...

The search of suitable combinations of stem cells, biomaterials and scaffolds manufacturing methods have become a major focus of research for bone engineering. The aim of this study was to test the potential of dental pulp stem cells to attach, proliferate, mineralize and differentiate on 3D printed polycaprolactone (PCL) scaffolds. A 100% pure Mw: 84,500 +- 1000 PCL was selected. 5 x 10 x 5 mm3 parallelepiped scaffolds were designed as a wood-pilled structure composed of 20 layers of 250 microm in height, in a non-alternate order ([0,0,0,90,90,90º]). 3D printing was made at 170 ºC. Swine dental pulp stem cells (DPSCs) were extracted from lower lateral incisors of swine and cultivated until the cells reached 80% confluence. The third passage was used for seeding on the scaffolds. Phenotype of cells was determined by flow Cytometry. Live and dead, Alamar blue™, von Kossa and alizarin red staining assays were performed. Scaffolds with 290 + 30 micron strand diameter, 938 x 80 micron pores in the axial direction and 689 x 13 micron pores in the lateral direction were manufactured. Together, cell viability tests, von Kossa and Alizarin red staining indicate the ability of the printed scaffolds to support DPSCs attachment, proliferation and enable differentiation followed by mineralization. The selected material-processing technique-cell line (PCL-3D printing-DPSCs) triplet can be though to be used for further modelling and preclinical experiments in bone engineering studies.

[EN] Fifty years after the first human landed on the Moon mankind has started to plan the next steps for manned space exploration missions. When the time required to return to Earth exceeds 400-500 days (as in travels to Mars), the level of independence that the crew must possess is highly increased. To ensure the survival and good living conditions of this future explorers, new developments regarding medical infrastructure and resources must be carried out. In this work, the topic of this study was to investigate how 3D printing and bioprinting can be of use to improve the autonomy of the crew when facing the most probable clinical scenarios that can occur in long-term space exploratory missions. The printing parameters of thermoplastics, such as polycaprolactone (PCL), that can be used as a possible support material along bioprinting were studied, including the use or not of alternate layers or the printing starting point. For bioprinting, and taking bone constructs as the tissue of study, a new bioink based on human plasma (which potentially could be derived from the injured astronaut who needs the treatment), alginate, and methylcellulose (that can be grow and used in isolated areas) was designed. An inverted bioprinter was designed and built to be able to test the work capacity of this biomaterial in altered gravity conditions. As result, it was observed that the use of alternated layers involves the generation of more anisotropic structures, as the z-axis pore is limited to the layer height, while the x and y-pore size can be tailored to specific needs. The defects created because of the alignment, or the lack of it, at the new layer starting point, significantly affects the mechanical behavior of the scaffolds. ix The cooling down rate, or even printing speed, can be modified to obtain more chaotic micropatterns including nanofibers without the need of using further technologies. A plasma-based bioink was successfully designed and combined with hydroxyapatite, [ES] 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. En este trabajo, se estudió cómo la impresión 3D y la bioimpresión pueden ser de utilidad para mejorar la autonomía de la tripulación ante los escenarios clínicos más probables que pueden ocurrir en misiones de larga duración. Para ello se estudiaron algunos parámetros de impresión de termoplásticos, como la policaprolactona (PCL), que pueden utilizarse x como posible material de soporte a lo largo de la bioimpresión (ejemplo de parámetros: uso o no de capas alternas o la alineación del punto de partida de la impresión en cada capa). Para la bioimpresión, y tomando las construcciones óseas como tejido de estudio, se diseñó un nuevo material compuesto a base de plasma humano (que puede ser obtenido de los astronautas), alginato y metilcelulosa (que se puede obtener y utilizar en áreas aisladas). Se diseñó y construyó una bioimpresora invertida para poder probar la capacidad de trabajo de este biomaterial en condiciones de gravedad alterada. Como resultado se obtuvo que el uso de capas alternas implica la generación de más estructuras anisotrópicas, ya que normalmente el poro del eje z está limitado a la altura de la capa, mientras que el tamaño de los poros x e y se pueden adaptar a necesidades especıificas. Los defectos creados por la alineación, o la falta de ella, en el punto de inicio de la nueva capa, afectan significativamente al comportamiento mecánico de los andamios. La velocidad de enfriamiento, o inc