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Municipal solid waste incineration (MSWI) generates high amounts of bottom ash that, after grinding, could be used as mineral addition for concrete. Wet grinding of the bottom ash can prevent the risk of deleterious expansion due to hydrogen evolution, associated to the presence of metallic aluminium. The pozzolanic behavior of the bottom ash may improve concrete resistance to the penetration of aggressive species. Advantages of recycling wet-ground MSWI bottom ashes may even be higher when self-compacting concrete (SCC) is used, which requires large quantity of fine powders (usually more than 500 kg/m3) to prevent segregation of the fresh mix. This paper describes the results of a research aimed at investigating the use of wet-ground MSWI bottom ashes as mineral additions for the production of self-compacting concrete. Several types of mineral additions (MSWI bottom ash, coal fly ash, and ground limestone) were used in replacement of 15, 30, and 45% of Portland cement. The results showed that the MSWI ash, added to the mix as a fine slurry obtained by wet-grinding, led to the production of SCC concrete with compressive strength and resistance to chloride and carbonation similar, or even better, than those of concrete with same amount of coal fly ash. [ABSTRACT FROM AUTHOR]

No-fines concrete with a compressive strength in the range 7-30MPa at 28days of curing were optimized by changing the water/cement ratio from 0.41 to 0.34 and the aggregate/cement ratio from 8 to 4. Some mixtures were also repeated with the addition of a hydrophobic admixture and prepared by fully replacing the ordinary aggregate with recycled aggregate to evaluate durability effects. High susceptibility to carbonation was observed for all the no-fines mixes studied. The use of recycled aggregate increases capillary water absorption (about 50%); however, the related decrease in durability could be easily counteracted with the use of a hydrophobic admixture. [ABSTRACT FROM AUTHOR]

Highlights: [•] Customised specimens with steel fibres or rebars were subjected to direct stray current. [•] The conditions required to circulate current in the fibres/rebars were investigated. [•] The length of the reinforcement is the predominant requirement for current transfer. [•] The risk of stray current induced corrosion of steel fibre reinforced concrete is very low in real structures. [ABSTRACT FROM AUTHOR]

Abstract: Although no-fines concrete has been generally used for paving applications, it could be considered in other non-structural applications, such as reinforced panels, thanks to its acoustic, thermal and permeability properties. In this work, mechanical, durability-related properties and the protection provided by no-fines concrete to embedded steel against carbonation-induced corrosion have been investigated on mixtures with compressive strength in the range 7–30MPa. Additional protections, such as a mixed-in hydrophobic admixture, the coating of cement paste on the reinforcing bar or the use of galvanized or stainless steel bars, are also considered. Results show that, although no-fines concrete is susceptible to fast carbonation and it cannot provide long-term passivation to embedded steel, it may prevent corrosion in elements exposed to the atmosphere and sheltered by rain. In case of frequent contact with water, additional protections are required, preferably based on the use of corrosion resistant bars. [Copyright &y& Elsevier]

The topic of sustainability of reinforced concrete structures is strictly related with their durability in aggressive environments. In particular, at equal environmental impact, the higher the durability of construction materials, the higher the sustainability. The present review deals with the possible strategies aimed at producing sustainable and durable reinforced concrete structures in different environments. It focuses on the design methodologies as well as the use of unconventional corrosion-resistant reinforcements, alternative binders to Portland cement, and innovative or traditional solutions for reinforced concrete protection and prevention against rebars corrosion such as corrosion inhibitors, coatings, self-healing techniques, and waterproofing aggregates. Analysis of the scientific literature highlights that there is no preferential way for the production of "green" concrete but that the sustainability of the building materials can only be achieved by implementing simultaneous multiple strategies aimed at reducing environmental impact and improving both durability and performances.

The paper represents the "state of the art" on sustainability in construction materials. In Part 1 of the paper, issues related to production, microstructures, chemical nature, engineering properties, and durability of mixtures based on binders alternative to Portland cement were presented. This second part of the paper concerns the use of traditional and innovative Portland-free lime-based mortars in the conservation of cultural heritage, and the recycling and management of wastes to reduce consumption of natural resources in the production of construction materials. The latter is one of the main concerns in terms of sustainability since nowadays more than 75% of wastes are disposed of in landfills.

This review presents "a state of the art" report on sustainability in construction materials. The authors propose different solutions to make the concrete industry more environmentally friendly in order to reduce greenhouse gases emissions and consumption of non-renewable resources. Part 1-the present paper-focuses on the use of binders alternative to Portland cement, including sulfoaluminate cements, alkali-activated materials, and geopolymers. Part 2 will be dedicated to traditional Portland-free binders and waste management and recycling in mortar and concrete production.

A phase I clinical trial using autologous, IL-7 gene-modified tumor cells in patients with disseminated melanoma has been recently completed. Although no major clinical responses were observed, increased antitumor cytotoxicity was measured in postvaccine peripheral blood lymphocytes in a subset of treated patients. To analyze the in situ immune response, the T cell receptor beta-chain variable region (BV) repertoire of T cells infiltrating postvaccine lesions was studied in two patients, and compared with that of T cells present in prevaccine ones, in peripheral blood lymphocytes, and, in one patient, in delayed type hypersensitivity (DTH) sites of autologous melanoma inoculum. A relative expansion of T cells expressing few BVs was observed in all postvaccine metastases, and their intratumoral presence was confirmed by immunohistochemistry. Length pattern analysis of the complementarity determining region 3 (CDR3) indicated that the repertoire of T cells expressing some of these BVs was heterogeneous. At difference, CDR3, beta-chain joining region usage, and sequence analysis enabled us to demonstrate, within a T-cell subpopulation commonly expanded at DTH sites and at the postvaccine lesion of patient 1, that both DTH sites contained identical dominant T-cell clonotypes. One of them was also expressed at increased relative frequency in the postvaccine lesion compared to prevaccine specimens. These results provide evidence for immunological changes, including in situ clonally expanded T cells, in metastases of patients vaccinated with IL-7 gene-transduced cells.

The role of endogenous NO on cell survival was investigated in human melanoma cells and melanocytes. Inducible NO synthase (iNOS) was always expressed in a panel of melanoma cell lines from metastatic lesions and in normal adult melanocytes. iNOS was also detected by immunohistochemistry in melanoma cells from metastases. Release of NO by tumor cells and melanocytes was inhibited by a specific iNOS inhibitor, aminoguanidine (AMG). Inhibition of endogenous NO synthesis did not affect cell cycle progression of melanoma cells but led to cell death by apoptosis, as indicated by Annexin V/propidium iodide and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling assays. By contrast, iNOS inhibition by AMG did not promote apoptosis in normal adult melanocytes. A mitochondrial pathway was involved in melanoma apop tosis, as indicated by altered mitochondrial membrane potential (delta psi(m)) and down-regulation of Bcl-2 protein level after iNOS inhibition. AMG treatment triggered release of caspase-1, enzymatic activation of caspase-3, and degradation of poly(ADP-ribose) polymerase, one of the main caspase-3 substrates. Melanoma cell apoptosis induced by iNOS inhibition was completely blocked by peptide inhibitors of caspase-1 and caspase-3 (Ac-DEVD-CHO and AC-YVAD-CHO) or by an exogenous NO donor, sodium nitroprusside, or by addition of serum. Finally, comparison of control and AMG-treated melanoma cells by pathway-specific gene array analysis indicated that inhibition of NO synthesis led, before induction of apoptosis, to up-regulation of mRNA levels of genes involved in the apoptosis pathway such as Bax, caspase-1, caspase-3, caspase-6, gadd45beta, mdm2, and TRAIL. Taken together, these results indicate that melanoma cell survival is regulated by endogenous NO resulting from iNOS activity.