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Abstract: The aim of this work is the assessment of the possibility to produce geopolymeric materials for the specific use in the field of consolidation of stone materials or as restoration mortars, through mechanochemical activation of two solid precursors, quartz and kaolin. These starting materials were modified by grinding at different times and then the degree of reactivity of the obtained products was verified by studying the changes induced by the mechanical treatment on the crystalline structure and by determining the specific surface. Moreover the solubility and kind of alkaline solutions classically used for the production of geopolymeric materials (NaOH and KOH) was investigated together with other aqueous solutions at variable pH. The mechano-chemical activation process can achieve the result to reduce the use of alkaline solutions as activators of the starting raw materials in the production of consolidating solution for monument stone materials and to utilise natural materials in the production of restoration mortars compatible with the substrates to be restored. [Copyright &y& Elsevier]

A research project, funded by the Italian Ministry of Research and the European Union, is in progress aimed to develop processes to enhance, by irradiation, the safety and the wholesomeness of fresh products relevant for Italian food industry.Irradiation was performed on truffles, since the bacterial contamination impairs their trade in foreign countries. The microbial population and the shelf life under refrigeration were studied either on samples untreated or on samples submitted to γ-rays in a 1–2.5 kGy dose range. The effect of the treatment was monitored by UV and NMR techniques. Total microbial population and the shelf life prolongation were investigated. The synergistic effect of the dose, the packaging under vacuum and the storage/irradiation temperature resulted in a direct effect on the microbial load, spoilage and shelf life. After the irradiation, small variations in the intensity of some NMR resonances due to aromatic compounds and other unassigned compounds were observed. As confirmed by UV spectrophotometric data, these phenomena seemed to originate from a small degradation of polyphenols; the induced growth of soluble phenols suggested that the 1.5 kGy dose can be considered as the radiation dose threshold beyond which clear chemical modifications on truffles appear. [Copyright &y& Elsevier]

In this study we have investigated the state of water in a superabsorbing network based on hydroxyethylcellulose (HEC) and carboxymethylcellulose sodium salt (CMCNa) crosslinked with divinylsulfone (DVS).This type of network, at low degree of crosslinking, when exposed to distilled water is able to form a stable hydrogel containing an amount of water as high as 1000 times its own weight.De-hydrated/re-hydrated networks, containing different amounts of absorbed water, have been studied using differential scanning calorimetry (DSC) and NMR relaxometric methods. DSC analysis allowed the evaluation of freezable and non-freezable fractions of absorbed water showing also the presence of two types of freezable water. On the other hand, NMR relaxometry evidenced the presence of two hydration shells, characterized by a different mobility, which in both cases is lower than that of bulk water.An excellent quantitative agreement was found in the determination of the amount of freezable water using the two techniques.A comparison of the state of water in the crosslinked network and in the corresponding uncrosslinked mechanical mixture shows that in the last case micro-heterogeneity arises. [Copyright &y& Elsevier]

• The percentage of fracture healing in Sarmiento's cases is excellent, but it is difficult to be reproduced, and satisfactory results can also be achieved with operative treatment. • The incidence of malunions showed in conservative treatment may be completely avoided with ORIF (especially considering the varus deformity in conservative treatment). • The function is better in the immediate postoperative period, though we should remark that in the long term the function between the conservative and the surgical treatment is similar. • The incidence of postoperative radial nerve palsy is low and the recovery occurs in a reasonable time. Humeral shaft fractures represent about 3% of all fractures. While there are several treatment options for this type of fractures, there is no evidence in literature showing which is the best one. This study aims at analysing the outcomes for patients with humeral shaft fractures treated with Locking Compression Plate (LCP) fixation in our hospital and comparing them with the outcome for patients conservatively treated (according to data from Pubmed) , in order to determine the best treatment option. We treated surgically 220 humeral shaft fractures in our department from February 2005 to March 2012. Seventy-three of them met all the inclusion criteria for this study. All fractures were then classified according to the AO classification. The follow-up considered the radiographic healing of the fracture. All patients were treated with plate fixation (LCP - DePuySynthes Co). At the end of the four-year follow-up, the function was evaluated by means of the DASH score. A systematic review of the literature of the last 20 years was performed on MEDLINE (PubMed). We had 2 infections and 8 patients had postoperative nerve palsy which recovered in average time of 6.7 months. In addition, 4 fractures (5.48%) didn't heal within 6 months and they were considered as nonunions and healed after a second surgery. One of these 4 nonunions was infected. The mean DASH score was 18.24±19.18. No malunions were found. We identified 13 studies that were eligible for our systematic review. The mean non-union rate found was 17% in 2517 fractures with a follow-up that ranging from 67% to 100% of patients and a primary radial nerve palsy ranging from 0 to 115 patients. Malalignment rate ranged from 12.7 to 42%. After taking into account both the conservative and the surgical treatment, for humeral shaft fractures we suggest the operative treatment , because the patient's function of the upper limb recovers quickly in the immediate postoperative period and the incidence of malunions may be avoided. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a detailed analysis of effect induced by a dry ball milling process on cellulose structure, morphology and properties. The partial amorphization of cellulose was qualitatively estimated by ATR-FTIR analysis. Through WAXD analysis the crystallinity index and the mean size of the cellulose crystallite domains were calculated, both these parameters showing a progressive decrease as a function of the milling time. In particular, crystallinity index decreased from 0.53 to 0.15 after 60min ball milling, whereas the mean size of the cellulose crystallite domains showed a reduction from the original value of about 4.0nm up to about 3.4nm after 30min. These quantitative results were confirmed by 13C CP-MAS NMR analysis and measurements of the proton spin-lattice relaxation time in the rotating frame . Moreover, the increasing of the amount of water absorbed by cellulose samples (from 7.3wt% for untreated cellulose up to 11.6wt% for the cellulose sample ball milled for 60min) and the reduction of the thermal stability were evaluated by TGA. Finally, SEM analysis revealed that the original fibrous structure almost disappeared and was modified to a quasi-circular shape. [Copyright &y& Elsevier]

Abstract: The nuclear magnetic resonance (NMR) technique was used as analytical tool to determine the complete metabolic profiling of sea bass extracts: water-soluble metabolites belonging to different classes such as sugars, amino acids, dipeptides and organic acids as well as metabolites soluble in organic solvent such as lipids, sterols and fatty acids were identified. The metabolite profiling together with a suitable statistical analysis were used to discriminate between wild and cultured sea bass samples. Preliminary results show that discrimination between wild and cultured sea bass was obtained not only using fatty acid composition but also cholesterol and phosphatidylethanolamine and some water-soluble metabolites such as choline, trimethylamine oxide, glutamine, fumaric and malic acids. [Copyright &y& Elsevier]

Abstract: In order to increase the stability of Nafion conductivity at temperatures higher than 100°C, composite membranes made of recast Nafion filled with different percentages of zirconium phosphate (ZrP) were investigated. The membrane preparation was carried out by a simple synthetic procedure based on the use of solutions of ZrP precursors in dimethylformamide. The formation of insoluble α-type ZrP nanoparticles within the Nafion matrix was proved by 31P-MAS NMR and X-ray diffractometry. The membranes were characterized by TEM microscopy, ion-exchange capacity determinations, static stress–strain mechanical tests and conductivity measurements as a function of filler loading, at controlled relative humidity (r.h.) and temperature. An increasing filler loading results in enhanced membrane stiffness and in lower conductivity compared with pure recast Nafion. At 90% r.h. and 100°C, the conductivity decreases from ≈0.07Scm−1 for pure Nafion to ≈0.03Scm−1 for the composite membrane containing 25wt.% ZrP. Systematic conductivity measurements as a function of r.h. and temperature were carried out to draw a stability map for the conductivity of pure recast Nafion and of a composite membrane filled with 10wt.% ZrP. These maps provide for each r.h. value the maximum temperature at which the conductivity remains stable for at least 150h. The effect of zirconium phosphate is to increase the stability of conductivity at high temperature, with a gain up to 20°C. This stability enhancement has been ascribed to the higher stiffness of the composite membrane. [Copyright &y& Elsevier]

Abstract: An NMR and chemometric analytical approach to classify extra virgin olive oils according to their geographical origin was developed within the European TRACE project (FP6-2003-FOOD-2-A, contract number: 0060942). Olive oils (896 samples) of three consecutive harvesting years (2005, 2006, and 2007) coming from Mediterranean areas were analyzed by 1H NMR spectroscopy. Olive oil samples from Liguria, an Italian region, were chosen as a case study and PLS-DA and SIMCA modeling analyses were used to build up statistical models both to discriminate between Ligurian and non-Ligurian olive oils and to define the Ligurian olive oil class to confirm the declared provenience. [Copyright &y& Elsevier]

The network structure of a cellulose-based superabsorbing material has been probed by using three different techniques: 13C solid state NMR, free swelling in water and uniaxial compression of water swollen samples. A good agreement between the three apporaches has been found in terms of concentration of crosslinks per unit volume.The results have been discussed taking into account that NMR technique is able to detect only chemically effective crosslinks while free swelling and compression are sensitive to elastically effective physical and chemical crosslinks.A depression of swelling capacity and an apparent increase of degree of crosslinking with time, promoted by ageing of the cellulosic material, has been experimentally evidenced and discussed in terms of development of intermolecular physical interactions. [Copyright &y& Elsevier]