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The aim of the current study is to propose a versatile, non-destructive inspection strategy to evaluate the structure of two different aircraft carbon fibre reinforced polymer (CFRP) -based composite configurations, which are widely used for structural elements, respectively layered composite and sandwich structure. X-ray computed tomography (CT) has been used as a flexible method for assessment of porosity levels in CFRP components in both types of configuration, permitting to investigate the volume distribution of the individuated pores/voids, giving an interactive 3D exploration and quantitative analysis of porosity by the complete 3D volume rendering of the analysed composites. Moreover, specific data analysis could supply detailed information on size, shape and position of pores or defect or misalignment which could be a valuable indication for damage tolerant design methodology or local stress analysis. This presented non-destructive approach based on CT can be a good alternative to standard destructive methods based on the acid digestion or 2D microscopy for porosity evaluation in composite, especially for severe stressed element in aerospace structure. Of course, the high resolution X-ray CT cannot substitute the ultrasounds test for analysing full scale components, but it can be complementary to it to provide accurate quantitative results on small samples used as references.

Mapping the distribution of invasive species under current and future climate conditions is crucial to implement sustainable and effective conservation strategies. Several studies showed how invasive species may benefit from climate change fostering their invasion rate and, consequently, affecting the native species community. In the Canary Islands and on Tenerife in particular, previous research mostly focused on climate change impacts on the native communities, whereas less attention has been paid on alien species distribution under climate change scenarios. In this study, we modelled the habitat distribution of Pennisetum setaceum, one of the most invasive alien species on Tenerife. In addition, we described the species’ potential distribu- tion shift in the light of two climate change scenarios (RCP2.6, RCP8.5), highlighting the areas that should be prioritized during management and eradication programs. P. setaceum’s suitable areas are located in the coastal area, with higher habitat suitability near cities and below 800 m asl. In both future climate change scenarios, the geographic distribution of P. setaceum suitable areas is characterized by an eleva- tional shift, which is more pronounced in the RCP8.5 scenario. Despite being drought resistant, water supply is crucial for the species’ seed germination, thus supporting future species’ shift to higher elevation and in the north–north–west part of the island, where it could benefit from the combined effect of orographic precipitations and humidity carried by trade winds.

A citizen science initiative was launched in the province of Trieste, aimed at mapping the distribution of Ailanthus altissima, Ambrosia artemisiifolia and Senecio inaequidens. The reliability of citizen data was tested against control data obtained by trained personnel with a stratified random sampling. In spite of the lack of a strict sampling strategy, citizen data were highly correlated with control data. This was mainly due to: 1) the easy identification of the species and 2) the instructions given to citizens for selecting their observation areas and for avoiding duplicate records. The three species tend to be most frequent in disturbed areas; Ailanthus is highly concentrated in the urban area, Senecio is widely distributed but avoids the city centre, with the highest frequency in the industrial area and along the railways, Ambrosia has a similar pattern, but is most frequent in areas with calcareous substrata. The interpretation of the distribution patterns in terms of land use and ecological factors proved to be quite easy when the three species are considered together (higher frequency in disturbed areas), less so when they are considered separately, most probably because of historical and sociological factors, such as incomplete migration into the survey area, and "gentrification effects".

This study is aimed at investigating the structure of a scaffold made of bovine gelatin and hydroxyapatite for bone tissue engineering purposes. In particular, the detailed characterization of such a material has a great relevance because of its application in the healing process of the osteochondral defect that consists of a damage of cartilage and injury of the adjacent subchondral bone, significantly compromising millions of patient's quality of life. Two different techniques exploiting X-ray radiation, with table-top setups, are used: microtomography (micro-CT) and microdiffraction. Micro-CT characterizes the microstructure in the three dimensions at the micrometer scale spatial resolution, whereas microdiffraction provides combined structural/morphological information at the atomic and nanoscale, in two dimensional microscopy images with a hundred micrometer spatial resolution. The combination of these two techniques allowed an appropriate structural characterization for the purpose of validating the engineering approach used for the realization of the hydroxyapatite gradient across the scaffold, with properties close to the natural model. © 2016 American Chemical Society.

The water circulation and sediment transport in a shallow microtidal basin (the Lagoon of Marano-Grado, Italy) were investigated by means of a 3D finite element modelling system. The framework of the numerical model consists of a 3D finite element hydrodynamic model, a third generation unstructured spectral wave model and a sediment transport and morphodynamic model for both cohesive and non-cohesive sediments. In order to describe the exchange of water and sediment through the lagoon's inlets, the model was applied to a domain comprising the lagoon itself and the whole Adriatic Sea. The developed model reproduces well the tidal motion and the wind induced circulation in the lagoon and the adjacent open sea. The transport of the fine sediments, resuspended by wind waves in the shallow tidal flats, resulted to be strongly related to the residual circulation induced by wind stress and nonlinear interaction between the tidal flow and bottom topography. The westward residual flow influences the exchange with the open sea through the six inlets, which therefore contribute with either a positive or negative net supply of water and sediment to the lagoon. The model provides estimates of the lagoon sediment budget revealing a net loss of about 40.10(3) m(3) of sediment in 2007. The results demonstrate the potential application of numerical models to simulate the recent morphological evolution and to improve the understanding of sediment dynamics in coastal embayments. (C) 2016 Elsevier B.V. All rights reserved.