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Concretes, mortars and grouts are used for structural and isolation purposes in radioactive and nuclear waste repositories. For example, concrete is used for deposition tunnel end plugs, engineered barriers, mortars for rock bolting and injection grouts for fissure sealing. Despite of the materials anticipated functionality, it is extremely important to understand the long-term material behaviour in repository environments. A reference concrete and mortar for the Cebama project based on a cement, silica and blast furnace slag ternary blend were designed and characterized in different laboratories with multiple experimental methods (XRD, XAS at the Fe and Cl K-edges, SEM-EDX, 29Si and 27Al MAS NMR, TG-DSC, MIP and Kerosene porosimetry) and techniques (punch strength tests). The reference concrete enabled comparison of results from different institutes and experimental techniques, unifying the individual results to more comprehensive body. The Cebama reference concrete and mortar were designed to have high durability and compatible formulation with respect to an engineered barrier system in clay or crystalline host-rocks, having pore solution pH significantly lower than traditional concretes. This work presents main results regarding their characterization and alteration in contact with representative waters present in radioactive waste repositories. Pore solution pH of the matured reference concrete was 11.4 - 11.6. The main hydrated phases were C-S-H and C-A-S-H gels with a Ca:Si ratio between 0.5- 0.7 and an Al:Si -ratio of 0.05. Minor phases were ettringite and hydrotalcite. Iron(III) could be in the C-S-H phases and no Cl-bearing solid phases were identified. Connected porosity and pore size distribution was characterized by MIP observing that, as expected, the size of the pores in the hydrated cement phases varies from the micro- to the nanoscale. Connected porosity of both materials were low. Compressive strength of the concrete was 115 MPa, corresponding to tr

Several classification systems have been proposed to address genomic heterogeneity of glioblastoma multiforme, but they either showed limited prognostic value and/or are difficult to implement in routine diagnostics. Here we propose a prognostic stratification model for these primary tumors based on tumor gene amplification profiles, that might be easily implemented in routine diagnostics, and potentially improve the patients management. Gene amplification profiles were prospectively evaluated in 80 primary glioblastoma multiforme tumors using singlenucleotide polymorphism arrays and the results obtained validated in publicly available data from 267/347 cases. Gene amplification was detected in 45% of patie

Application of nanotechnology in construction industry is a quite new field with many interesting and promising possibilities. Nanosilica self healing properties, based on the high reactivity of these particles with the calcium components of cement, are of great interest in rehabilitation treatments of hardened concrete. In present work, the application of nanosilica to hardened concrete is proposed as innovative technology to improve the effectiveness of electrochemical repair methods and to increase the durability of rehabilitated structures by sealing the concrete pores. An accelerated methodology, compatible with the electrochemical repair treatments of concrete, is proposed to introduce nanosilica in hardened concrete by connecting an external electric field. Two different commercial products with SiO2 of 7 nm and 12 nm in diameter have been analysed. Silica nanoparticles have been transported through a mortar sample under a 12 V electric field. The interaction between the SiO2 nanoparticles and the concrete have been characterised by different techniques: resistivity measurements, mercury intrusion porosity, scanning electron microscopy. The results show that the interaction concrete/nanosilica takes place in the first centimetre of concrete cover from the surface of the nanosilica application. A denser microstructure with higher content of capillary pores is obtained after the nanosilica penetration. Also the resistivity of the mortar increases due to the treatment with nanosilica.

Application of nanotechnology in construction industry is a quite new field with many interesting and promising possibilities. Nanosilica self healing properties, based on the high reactivity of these particles with the calcium components of cement, are of great interest in rehabilitation treatments of hardened concrete. In present work, the application of nanosilica to hardened concrete is proposed as innovative technology to improve the effectiveness of electrochemical repair methods and to increase the durability of rehabilitated structures by sealing the concrete pores. An accelerated methodology, compatible with the electrochemical repair treatments of concrete, is proposed to introduce nanosilica in hardened concrete by connecting an external electric field. Two different commercial products with SiO2 of 7 nm and 12 nm in diameter have been analysed. Silica nanoparticles have been transported through a mortar sample under a 12 V electric field. The interaction between the SiO2 nanoparticles and the concrete have been characterised by different techniques: resistivity measurements, mercury intrusion porosity, scanning electron microscopy. The results show that the interaction concrete/nanosilica takes place in the first centimetre of concrete cover from the surface of the nanosilica application. A denser microstructure with higher content of capillary pores is obtained after the nanosilica penetration. Also the resistivity of the mortar increases due to the treatment with nanosilica.