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The increasing bitumen cost, the growth of the traffic loads and the need to find more sustainable paving practices are forcing agencies to identify new ways to maximise the re-use of Reclaimed Asphalt (RA). If RA could theoretically be 100% recycled, its content in bituminous layers is still restricted in most countries mainly due to legislation limitations and technical issues. In particular, the stiffer and more brittle mixes, usually resulting from RA addition, have raised concerns about the long-term properties of the pavement. In order to further increase the amount of usable RA, rejuvenating additives can be included in the mixtures. The paper deals with the analysis of seven additives, with particular focus on their ability in mitigating the effects of the presence of RA in the mix as a function of production temperature. In particular, FTIR analysis was carried out on the additives to evaluate the differences in their chemical composition. Moreover, the mechanical properties of the mixtures including 50% RA and produced at 140°C or 170°C were investigated. The results showed the reduction of the mixing temperature from 170°C to 140°C determined a slight increase of the air voids content but also allowed a significant decrease of mix stiffness and strength with a contemporary increase of ductility. The mixtures containing 50% RA and the additive had an intermediate behaviour between the mix without RA and the mix with 50% RA and no additive. The additives investigated in this research showed, in most cases, different chemical structures, which reflected in their rejuvenating performance. The comparative analysis of the results from mechanical and chemical tests provided remarkable information about the characteristic properties of a good rejuvenator, particularly the presence of esters and the high flashpoint.

In recent years, over-stabilized polymer-modified bitumen emulsions have been widely used to improve the mechanical properties of cold bituminous mixtures. However, the effect of the polymer modification process on the emulsion performance have not been investigated. The present paper deals with the analysis of the binders recovered from a reference unmodified bitumen emulsion and two polymer-modified emulsions, respectively including SBR-latex added after bitumen emulsification (post-blending) and SBS added before bitumen emulsification (pre-blending). The laboratory investigation included the linear viscoelastic characterisation and the evaluation of the resistance to permanent deformations and damage. The results showed that the polymer-modified bitumen emulsions have a more pronounced elasticity with respect to the unmodified emulsion, allowing achieving a higher performance against permanent deformations and fatigue. In addition, the SBS modified bitumen emulsion (pre-blending) has better properties than the latex modified emulsion (post-blending), as a consequence of the different chemical structure that the modification process produces.

This paper presents a prominent e-learning tool that is part of deliverable packages of Hy2Green Project (Ref. 2017-1-ES01-KA203-038302). The aim of the project is to develop an online training course that can help to improve new professional profiles in hydrogen technologies, in line with the energy transition model in Europe. As part of this training course and as result of a team collaboration, a remote laboratory based on hydrogen technology has been designed and implemented. Through the online platform, students from every part of the world can access remotely and in real-time, to a real laboratory built from a scaled green-hydrogen production plant. The green-hydrogen production plant has, in addition to hydrogen production and storage subsystems, a fuel cell, through which electricity is generated with the stored hydrogen. The developed remote laboratory offers technological and educational improvements. From the technological point of view, it allows handling a real installation, throughout the entire energy conversion process, being able to carry out laboratory tests, to characterize the different components. This remote laboratory is proposed as a multidisciplinary tool, where students develop their skills in automatic control, system modelling and renewable energy management. On the other side, from the educational point of view, this proposal contributes to democratization of education. That is nowadays equipment related to hydrogen technology is not cheap, so this implies that not all educational centres cannot afford to have a hydrogen laboratory. The remote laboratory presented in this work offers the possibility to carry out laboratory practices to whatever the student and the university are.

Objective. To evaluate the contribution of the MHC class I chain-related A (MICA) gene polymorphism to the genetic risk of systemic lupus erythematosus (SLE).Methods. HLA-DRB1-DQA1-DQB1 genotyping, MICA exon 5 microsatellite genotyping and HLA-B8 genotyping were performed in 48 Italian SLE patients and in 158 healthy control subjects.Results. Of HLA class II haplotypes, only DRB1*03-DQA1*0501-DQB1*0201 (DR3-DQ2) was significantly more frequent among SLE patients than among healthy control subjects [odds ratio (OR) = 6.5, corrected P<0.0026]. HLA-B8 was detected in 31% SLE patients and 13% healthy control subjects (OR = 3.0, P = 0.005). The allele-wise comparison between patients and controls showed that both MICA5 (OR = 2.5, corrected P<0.0005) and MICA5.1 (OR = 2.4, corrected P<0.0005) were positively and MICA9 (OR = 0.2, corrected P<0.0005) was negatively associated with the disease. The MICA5/5.1 genotype was positively associated with SLE (OR = 28.9, corrected P<0.0015) also in subjects negative for DR3-DQ2 (OR>22.6, corrected P<0.011). The simultaneous presence of DR3-DQ2 and MICA5.1 was detected in 15/48 (31%) SLE and in 10/158 (6%) healthy control subjects (OR = 6.7, corrected P<0.011). The simultaneous combination of DR3-DQ2 and MICA5 was found in 10/48 (21%) SLE patients and in only 1/158 healthy control subjects (OR = 41.3, corrected P<0.011). Logistic regression analysis showed the independent positive associations of MICA5 and MICA5.1 and negative association of MICA9 with the disease, and revealed that the interaction of the three major markers (DR3-DQ2, MICA5 and MICA5.1) was associated with increasing genetic risk, which was highest (OR>30.3) in DR3-DQ2-positive subjects carrying the MICA5-5.1 genotype.Conclusions. Our study provides the first demonstration of the independent association of the MICA gene polymorphism with genetic risk of SLE.

Increased arterial stiffness has been reported in subjects with systemic lupus erythematosus (SLE) compared with healthy controls, and this association is partially reverted by immunosuppressive treatment. In SLE, indexes of organ damage are related to a poor clinical status and worse prognosis independently from the activity of the disease. Data are controversial about the association between organ damage and arterial stiffness in SLE.