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The article focuses on the creation and implementation of a new data acquisition strategy for the structural health monitoring (SHM) of the Giuseppe Meazza stadium in San Siro, Milan, Italy. It mentions the importance of identifying the most appropriate type of sensors layout for the implementation of the strategy. It also explains the reasons why crowd-induced vibrations should be measured. The equipment necessary for the implementation of the data acquisition strategy are mentioned.

New nickel (Ni)-reduced stainless-steel metals have recently been developed to avoid sensitivity to Ni. In the present study, an austenitic Ni-reduced SSt named P558 (P558, Bo¨hler, Milan, Italy) was studied in vitro on primary osteoblasts and in vivo after bone implantation in the sheep tibia, and was compared to ISO 5832-9 SSt (SSt) and Ti6Al4V. Cells were cultured directly on P558 and Ti6Al4V. Cells cultured on polystyrene were used as controls. Osteoblast proliferation, viability and synthetic activity were evaluated at 72 h by assaying WST1, alkaline phosphatase activity (ALP), nitric oxide, pro-collagen I (PICP), osteocalcin (OC), transforming growth factor-β1 (TGFβ-1) and interleukin-6 (IL-6) after 1.25(OH)2D3 stimulation. Under general anaesthesia, four sheep were submitted for bilateral tibial implantation of P558, SSt and Ti6Al4V rods. In vitro results demonstrated that the effect of P558 on osteoblast viability, PICP, TGF β-1, tumor necrosis factor-α production did not significantly differ from that exerted by Ti6Al4V and controls. Furthermore, P558 enhanced osteoblast differentiation, as confirmed by ALP and OC levels, and reduced IL-6 production. At 26 weeks, the bone-to-implant contact was higher in P558 than in SSt (28%, p<0.005) and Ti6Al4V (4%, p<0.05), and was higher in Ti6Al4V than in SSt (22%, p<0.005). The tested materials did not affect bone microhardness in pre-existing host bone as evidenced by the measurements taken at 1000 μm from the bone–biomaterial interface (F=1.89, ns). At the bone–biomaterial interface the lowest HV value was found for SSt, whereas no differences in HV were observed between materials (F=1.55, ns). The current findings demonstrate P558 biocompatibility both in vitro and in vivo, and osteointegration processes are shown to be significantly improved by P558 as compared to the other materials tested. [Copyright &y& Elsevier]