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P. Ruggeri, V.M.E. Fruzzetti, G. Scarpelli, “Renovation of quay walls to meet more demanding requirements: Italian experiences”, Coastal Engineering, 147 (May), 2019, 25-33
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Abstract:
Existing port structures often need to be upgraded to meet more demanding operational requirements caused by increasing ship size, deepening of the seabed and increasing crane dimensions and storage loads. When ports expand, upgrading is often preferable to the rebuilding of infrastructures in term of costs; however, the design of such works must take into account that the reliability of the existing structures is often inadequate according to the current codes, due to the low mechanical properties of the original materials and to their aging in the highly aggressive marine environment. The geotechnical engineering literature rarely addresses the problem of upgrading existing quay walls, even though such geotechnical structures are extremely challenging. This paper discusses the main issues involved in the geotechnical design for upgrading existing quay walls, through the presentation of some case histories drawn from past experiences in Italy.
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A.L. Osterman, I. Rodionova, X. Li, E. Sergienko, C.T. Ma, A. Catanzaro, M.E. Pettigrove, R.W. Reed, R. Gupta, K.H. Rohde, K.V. Korotkov, L. Sorci, “Novel Antimycobacterial Compounds Suppress NAD Biogenesis by Targeting a Unique Pocket of NaMNAdenylyltransferase”, ACS Chemical Biology, 14 (May), 2019, 949-958
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Abstract:
Conventional treatments to combat the tuberculosis (TB) epidemic are falling short, thus encouraging the search for novel antitubercular drugs acting on unexplored molecular targets. Several whole-cell phenotypic screenings have delivered bioactive compounds with potent antitubercular activity. However, their cellular target and mechanism of action remain largely unknown. Further evaluation of these compounds may include their screening in search for known antitubercular drug targets hits. Here, a collection of nearly 1400 mycobactericidal compounds was screened against Mycobacterium tuberculosis NaMNadenylyltransferase (MtNadD), a key enzyme in the biogenesis of NAD cofactor that was recently validated as a new drug target for dormant and active tuberculosis. We found three chemotypes that efficiently inhibit MtNadD in the low micromolar range in vitro. SAR and cheminformatics studies of commercially available analogues point to a series of benzimidazolium derivatives, here named N2, with bactericidal activity on different mycobacteria, including M. abscessus, multidrug-resistant M. tuberculosis, and dormant M. smegmatis. The on-target activity was supported by the increased resistance of an M. smegmatis strain overexpressing the target and by a rapid decline in NAD(H) levels. A cocrystal structure of MtNadD with N2-8 inhibitor reveals that the binding of the inhibitor induced the formation of a new quaternary structure, a dimer-of-dimers where two copies of the inhibitor occupy symmetrical positions in the dimer interface, thus paving the way for the development of a new generation of selective MtNadD bioactive inhibitors. All these results strongly suggest that pharmacological inhibition of MtNadD is an effective strategy to combat dormant and resistant Mtb strains.
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G. Barucca, D. Rinaldi, et Al., “Precision resonance energy scans with the PANDA experiment at FAIR”, Eur. Phys. J. A (2019) 55: 42
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Abstract:
This paper summarises a comprehensive Monte Carlo simulation study for precision resonanceenergy scan measurements. Apart from the proof of principle for natural width and line shape measurementsof very narrow resonances with PANDA, the achievable sensitivities are quantified for the concrete example eof the charmonium-likeX(3872) state discussed to be exotic, and for a larger parameter space of variousassumed signal cross-sections, input widths and luminosity combinations. PANDA is the only experiment that will be able to perform precision resonance energy scans of such narrow states with quantum numbersof spin and parities that differ fromJPC=1−−.
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F. Stazi, C. Urlietti, C. Di Perna, G. Chiappini, M. Rossi, F. Tittarelli, Thermal and mechanical optimization of nano-foams for sprayed insulation, Construction and Building Materials 201 (2019) 828-841.
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Abstract:
This study investigates the effects of the addition of two different types of particles on morphological, thermo-hygrometric and mechanical properties of thermal insulating sprayed polyurethane foams.
Platelet nanoclay and spherical silicon dioxide microparticles were poured into two different foams with a density of 15 Kg/m3 and 30 Kg/m3, respectively used for cavity walls infill and external insulation layers.
Nanoclay particles were dispersed into the polyol through a sonication technique followed by a mechanical mixing into the isocyanate, whereas silica dioxide microparticles (aerogel) were mixed mechanically into the polyol then added to isocyanate.
Results showed that the introduction of small amounts (2% and 4% in weight) of nanoparticles and microparticles significantly enhances both thermal and mechanical properties of the foams. Among the low-density foams, the best thermal performance was recorded by 4 wt% nanoclay sample with a reduction of the conductance of about 9% whereas the best mechanical performance was recorded by 4 wt% aerogel sample with an increase of the tensile modulus of about 300%. However even the 4wt% nanoclay addition significantly enhanced the outcomes of the mechanical tests. Also among the highdensity foams, the best thermal and mechanical compromise was achieved by the one containing 4% in weight of nanoclay, that showed a reduction of the conductance of about 7% and an increase of the tensile modulus of about 180%. This latter sample resulted to be the most performing among all the foams.
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Silvio Bonfadini, Fabrizio Ciciulla, LuiginoCriante, Annamaria Zaltron, Francesco Simoni, Victor Reshetnyak and Liana Lucchetti“Optofuidic platform using liquid crystals in lithium niobate microchannel”, Scientific Reports, 9, 1062, 2019, 1-9
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Abstract:
We demonstrate the all optical control of the molecular orientation of nematic liquid crystals confined in microfuidic channels engraved in lithium niobate. Microchannels are obtained by a novel approach based on femtosecond pulse laser micromachining carried on in controlled atmosphere. The combined effect of photovoltaic and pyroelectric fields generated by light in lithium niobate crystals on the liquid crystal orientation, is reported for the frst time. The total space charge field and its dependence on the incident light intensity can be controlled by changing the direction of pump light propagation through the microfuidic chip. The results reported in this manuscript demonstrate that liquid crystals and lithium niobate can efficiently be combined in microfuidic configuration, in order to push forward a novel class of optofuidic devices.
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F. Stazi, M. Serpilli, G.Maracchini, A. Pavone, “An experimental and numerical study on CLT panels used as infill shear walls for RC buildings retrofit”, Construction and Building Materials, 211 (June), 2019, 605-616
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Abstract:
Cross Laminated Timber (CLT) has been gaining more and more attention in research and professional fields as a sustainable and promising construction system for mid- and high-rise structures. The need of buildings higher than those usually built with CLT has pushed the research towards the development of innovative hybrid techniques in which steel framed structures incorporate CLT shear walls. This concept may be potentially extended to existing RC framed buildings, where CLT infill shear walls may constitute the base of an integrated seismic and energy retrofit. In order to investigate this potentiality, this paper presents a preliminary experimental and numerical study focused on the mechanical behavior of CLT panels used as a bracing system. In particular, diagonal compression tests on 3-ply panels have been carried out, also by reproducing a direct load transmission from the RC frame to the CLT infill. A comparison with the results of similar tests on CLT panels (with a different number of layers and thickness) and with unstrengthened and strengthened masonry infill walls has been also provided. In addition, numerical simulations have been carried out, in order to evaluate the changes in RC frame lateral response when CLT infills are added. The results have proved that CLT infills may be used as a strengthening solution, allowing RC frame to reach higher lateral stiffness and peak load values respect to masonry infills.
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Mercer, E., Davey, C.J., Azzini, D., Eusebi, A.L., Tierney, R., Williams, L., Jiang, Y., Parker, A., Kolios, A., Tyrrel, S., Cartmell, E., Pidou, M., McAdam, E.J., 2019, “Hybrid membrane distillation reverse electrodialysis configuration for water and energy recovery from human urine: An opportunity for off-grid decentralised sanitation”, Journal of Membrane ScienceVolume 584, 15 August 2019, Pages 343-352
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Abstract:
The integration of membrane distillation with reverse electrodialysis has been investigated as a sustainable sanitation solution to provide clean water and electrical power from urine and waste heat. Reverse electrodialysis was integrated to provide the partial remixing of the concentrate (urine) and diluate (permeate) produced from the membrane distillation of urine. Broadly comparable power densities to those of a model salt solution (sodium chloride) were determined during evaluation of the individual and combined contribution of the various monovalent and multivalent inorganic and organic salt constituents in urine. Power densities were improved through raising feed-side temperature and increasing concentration in the concentrate, without observation of limiting behaviour imposed by non-ideal salt and water transport. A further unique contribution of this application is the limited volume of salt concentrate available, which demanded brine recycling to maximise energy recovery analogous to a battery, operating in a ‘state of charge’. During recycle, around 47% of the Gibbs free energy was recoverable with up to 80% of the energy extractable before the concentration difference between the two solutions was halfway towards equilibrium which implies that energy recovery can be optimised with limited effect on permeate quality. This study has provided the first successful demonstration of an integrated MD-RED system for energy recovery from a limited resource, and evidences that the recovered power is sufficient to operate a range of low current fluid pumping technologies that could help deliver off-grid sanitation and clean water recovery at single household scale
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Longo, S., Mauricio-Iglesias, M., Soares, A., Campo, P., Fatone, F., Eusebi, A.L., Akkersdijk, E.d, Stefani, L., Hospido, A., 2019, “ENERWATER – A standard method for assessing and improving the energy efficiency of wastewater treatment plants”.Applied Energy15 May 2019, Pages 897-910
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Abstract:
This paper describes the first methodology specifically tailored to estimate energy efficiency at wastewater treatment plants (WWTPs). Inspired by the cycle of continuous improvement, the method (i) precisely defines the concept of energy efficiency in WWTPs, (ii) proposes systematic and comparable ways to measure it, and (iii) allows benchmarking and diagnosing energy hotspots. The methodology delivers an aggregated measure of the WWTP energy efficiency defined as the Water Treatment Energy Index, a single energy label that uses universally known illustrations enabling wide communication of standardized information on the WWTP energy status. The accuracy, reproducibility and generality of the methodology were validated by a widespread energy benchmarking method, and a case study is presented to show its capabilities. By promoting dialogue towards the creation of a specific European Standard, the actions accomplished by the H2020 Coordination Support Action ENERWATER should positively contribute to improving the exchange of information on energy saving actions and results between wastewater utilities and towards other stakeholders
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L. Denti, E. Bassoli, A. Gatto, E. Santecchia, P. Mengucci, “Fatigue life and microstructure of additive manufactured Ti6Al4V after different finishing processes”, Materials Science & Engineering A 755 (2019) 1–9
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Abstract:
Finishing methods of additive manufactured metal parts are becoming a key driver of industrial viability, increasingly with additive processes being challenged in demanding end-product applications. The same scenario stresses the requirements as to fatigue life of parts built by Additive Manufacturing (AsM).
The paper addresses fatigue life of Ti6Al4V produced by Powder Bed Fusion in four finishing conditions: asbuilt, tool machined, after tumbling and after tumbling and subsequent shot-peening. Failure mechanisms at the micro-scale are observed in order to reinforce the mechanical results by identifying the role of different surface morphologies in crack initiation. X-ray diffraction (XRD), scanning electron microscopy (SEM) techniques and microanalysis (EDX) are used to investigate microstructural modifications generated by the different finishing methods. Results show that tumbling alone does not improve fatigue life against the as built condition, whereas tumbling and subsequent shot peening allow matching the fatigue endurance of tool machined specimens. The shot peening process causes surface amorphization and implantation of the peening media turning into subsurface inclusions. Based on the results, an optimized finishing process can be envisaged, consisting in prolonged tumbling up to the removal of a stock allowance at least equal to the powder size, before shot peening.
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Chiara Lo Porto, Rosa Di Mundo, Valeria Veronico, Ilaria Trizio, Gianni Barucca, Fabio Palumbo, “Easy Plasma Nano-texturing of PTFE Surface: from pyramid to unusual spherules-on-pyramid features”, Applied Surface Science 483 (July), 2019, 60-68
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Abstract:
Oxygen plasma etching of polytetrafluoroethylene has been investigated as a way to sculpture nano-features on its surface and producing a super-hydrophobic material in one step. It has been found that, depending on the experimental conditions, the shape of the structures engraved in the polymer surface passes from pyramidal to unique pyramids with well-defined spherules on the top. The latter are obtained without any mask/lithographic option. In a previous paper the water-repellent character of such etched polytetrafluoroethylene surface has been well documented and explained by some of the authors. In this paper, instead, some insights in the formation mechanism of such unusual morphology are provided. Chemical and morphological characterization indicate in the iron surface contamination the clue for the formation of such complex agglomerates.
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A.Rocchi, E. Santecchia, F.Ciciulla, P. Mengucci, G. Barucca, “Characterization and optimization of level measurement by an ultrasonic sensor system”, IEEE Sensors journal 19(8) (April), 2019, 3077-3084
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Abstract:
The problem of environmental disasters due to oil spills has characterized recent history from the early ‘900, still being an important risk factor for environmental protection. Aim of this research is designing and implementation of a non-contact ultrasonic sensor system capable of providing the water level in the marine environment. This system is part of a very low-cost device developed to detect water pollution by non-conductive liquids (i.e., hydrocarbons floating in the sea), exploiting the different conductivities of fluids involved. While equipment and techniques currently used for monitoring marine water pollution are very expensive, this paper focuses on the characterization of a low-cost SRF05 ultrasonic sensor and on its implementation inside a floating organ as a result of data obtained from laboratory tests. A number of experimental tests were conducted using a micrometric linear stage, a triangulation laser, a digital oscilloscope, and a post-processing software. Moreover, changes of climatic conditions, such as temperature and humidity, were monitored in a climatic chamber, aiming to establish the best operating range in terms of sensor resolution and the architecture of a buoy. The sensor showed signal anomalies at regular distance intervals due to anticipated flight times, which led to the adoption of a sensor system consisting in the combination of more SRF05 sensors to optimize the measurement system. In addition, it is presented an analytical method based on ultrasonic signal reconstruction, with the aim to improve the accuracy of the measurement method. The final device is managed to have a sensibility of about 1 mm.
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Gaspare Varvaro, Antonio Di Trolio, Antonio Polimeni, Alessio Gabbani, Francesco Pineider, César de Julián Fernández, Gianni Barucca, Paolo Mengucci, Aldo Amore Bonapasta and Alberto Maria Testa, “Giantmagneto-optical response in H+ irradiated Zn1-xCoxO thin films”,Journal of Materials Chemistry C 7(1), 2019,78-85
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Abstract:
Remarkable improvements in the magneto-optical properties of Zn1−xCoxO thin films were achieved by post-growth hydrogen irradiation at temperatures of 400 °C. Hydrogen incorporation increases the magnetic circular dichroism signal resulting in large values of ellipticity and Faraday rotation at room temperature. The hysteretic behavior of the magneto-optical field dependent loops at different sub-bandgap wavelengths indicates an intrinsic ferromagnetic regime. A giant Faraday rotation of 3000 deg cm−1 was observed at 400 nm. Optical, structural and microstructural characterizations pointed out the Zn substitution by Co, ruling out the presence of noticeable Co-related secondary phases down to the nanoscale. The increased values of saturation magnetization, ellipticity and Faraday rotation have been explained based on an impurity band close to the conduction band minimum, which is induced by Co-VO (O vacancies) complexes. A phenomenological model founded on such an impurity band and electronic states induced by other Co-defect complexes in the ZnO energy gap allows a thoroughly novel, fine interpretation of the ellipticity spectra.
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Mastrocicco, M., Colombani, N., Soana, E., Vincenzi, F., Castaldelli, G. “Intense rainfalls trigger nitrite leaching in agricultural soils depleted in organic matter”, Science of the Total Environment, 665 (May), 2019, 80-90
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Abstract:
Nitrate and ammonium are common inorganic contaminants of anthropogenic origin in many shallow aquifers around the world, while nitrite is less common, but it is most harmful than nitrate and ammonium due to its high reactivity. This paper presents evidence of nitrite accumulation after intense rainfalls in soil samples collected in an agricultural field characterized by organic matter chronic depletion. Moreover, an intact core from the same site was also collected to perform an unsaturated column experiment (60 cm long and 20 cm outer diameter) mimicking heavy rainfalls (230 mm in 2 days). Results from the field site showed nitrite accumulation (up to 0.45 mmol/kg) at 50–70 cm depth, just below the plough layer. The column experiment showed very high initial concentrations of nitrate and nitrite in the leachate and a progressive decrease of nitrate due to denitrification. The numerical flow model was calibrated versus the observed volumetric water contents and leachate flow rates. The numerical reactive transport model was calibrated versus the leachate concentrations of six dissolved species (ammonium, nitrate, nitrite, dissolved organic carbon, chloride and bromide). The optimized model resulted to be robustly calibrated providing insights on the kinetic rates driving the production, accumulation and leakage of nitrite, showing that incomplete denitrification is the source of nitrite. As far as the authors are aware, this is the first study reporting a clear link between high nitrite leaching rates and extreme rainfall events in lowland agricultural soils depleted in organic matter. The proposed methodology could be applied to quantify nitrite cycling processes in many other agricultural areas of the world affected by extreme rainfall events.
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Castaldelli, G., Colombani, N., Soana, E., Vincenzi, F., Fano, E.A., Mastrocicco, M. “Reactive nitrogen losses via denitrification assessed in saturated agricultural soils”, Geoderma, 337 (March), 2019, 91-98
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Abstract:
The aim of the present study was to quantify nitrate (NO3−) removal via denitrification in an intensively cropped lowland of the Po River delta (Northern Italy). These agricultural lands are characterized by fine textured soils, generally poor of labile organic matter and amended mainly with synthetic fertilizers. Laboratory core incubations in water saturation conditions were performed on two contrasting soil types distinguished by different soil textures (silty-loam and silty-clay) either amended with NO3− alone or a combination of NO3− and acetate. Denitrification was evaluated by concomitant measurements of NO3− consumption and N2 production via N2:Ar analyses by Membrane Inlet Mass Spectrometry (MIMS). The water-logged soils showed higher capacity to reduce NO3− to N2 when supplied with acetate as an organic substrate, while, without acetate amendment, NO3− removal was limited due to lack of labile organic substrates. Transient nitrite (NO2−) accumulation was documented in acetate amended mesocosms, due to concurrent presence of elevated pH values and use of highly oxidized substrates (like acetate). This study suggests that agricultural practices aimed to increase the availability of labile organic matter, such as acetate, are beneficial in buffering reactive N excess in soils and to reduce NO3− leaching towards groundwater and surface-water.
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Kazakis, N., Busico, G., Colombani, N.,Mastrocicco, M., Pavlou, A., Voudouris, K. “GALDIT-SUSI a modified method to account for surface water bodies in the assessment of aquifer vulnerability to seawater intrusion”, Journal of Environmental Management, 235 (April), 2019, 257-265
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Abstract:
The salinization of coastal aquifers is one of the major environmental issue worldwide. Overexploitation is the most common reason of salinization, since it generates a piezometric inversion, which in turn leads to groundwater flow from the coast towards inland. This also occurs in water bodies connected to the sea like lagoons, rivers, torrents and wetlands. In this study, a modification of the GALDIT method including “SUperficial Seawater Intrusion (SUSI)” is proposed. Six new parameters were added to the classical ones. The analytical hierarchy process and the sensitivity analysis were performed for weights definition and validation of the proposed GALDIT-SUSI method. Two study areas, with different characteristics were chosen for the application of both methods: the coastal area of Epanomi (Greece) and the Po River lowland (Italy). The application of the standard GALDIT in both sites showed a poor discrimination of the vulnerability to seawater intrusion, confining it only in proximity to the coastline. Conversely, GALDIT-SUSI divided the two sites in five classes of vulnerability ranging from very low to very high, stressing the higher vulnerability of lagoons and wetland for Epanomi and lagoons and rivers for the Po River lowland. GALDIT-SUSI is easy to apply and versatile, since it can be adapted to the specific hydrogeological setting of the area of interest. Moreover, GALDIT-SUSI can be further improved to deal with other salinization mechanisms.
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Mastrocicco, M., Busico, G., Colombani, N. “Deciphering interannual temperature variations in springs of the Campania region (Italy)”, Water (Switzerland), 11(2) (February), 2019, Article number 288
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Abstract:
While the effects of climate change on the thermal regimes of surface waters have already been assessed by many studies, there is still a lack of knowledge on the effects on groundwater temperature and on the effects on spring water quality. The online available dataset of the Campania Environmental Agency (ARPAC) was analysed via spatial, temporal and statistical analyses to assess the impact of climate variability on 118 springs, monitored over the period from 2002 to 2017. The meteorological dataset was used to compute average annual precipitation and atmospheric temperatures. Spring water temperatures, electrical conductivity, pH, chloride and fluoride were selected to determine if climate variations had a significant impact on spring water quality. This study shows that the Campania region has experienced an increase of spring water temperatures of approximately 2.0 °C during the monitored period. This is well-linked with the increase of atmospheric minimum temperatures, but not with average and maximum atmospheric temperatures. The spring water temperature increases were not reflected by a concomitant change of the analysed water quality parameters. The latter were linked to the precipitation trend and other local factors, like spring altitude and the presence of geothermal heat fluxes.
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Mastrocicco, M., Colombani, N., Castaldelli, G. “Direct measurement of dissolved dinitrogen to refine reactive modelling of denitrification in agricultural soils”, Science of the Total Environment, 647 (January), 2019, 134-140
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Abstract:
Nitrogen fertilizers used in agriculture often cause nitrate leaching towards shallow groundwater, especially in lowland areas where soil permeability, ploughing, clay content, and the flat topography minimizes surface runoff. The introduction of good agricultural practices to reduce the nitrate amount entering the groundwater system is crucial to ameliorate the kinetic control on nitrate denitrification capacity. With this aim, a series of anaerobic mesocosms, consisting of loamy and clay soils and nitrate rich water, were modelled using acetate and natural organic matter as electron donors. Acetate was chosen because it is the main intermediate in many biodegradation pathways of organic compounds, and hence it is a suitable carbon source for denitrification. To account for the spatial variability of soil parameters, the experiments were performed in triplicates. The geochemical code PHREEQC(3) was used to simulate kinetic denitrification, and equilibrium reactions of gas and mineral phases. The reactive modelling results highlighted a rapid acetate and nitrate degradation rate, a rapid production of dissolved inorganic carbon and dinitrogen, and a steady concentration of dissolved iron and sulphate, suggesting that the main pathway of nitrate attenuation is through denitrification; concomitantly excluding the occurrence of other processes leading to nitrate consumption. In the absence of acetate, the loamy soil, poor of natural organic matter, did not allow to complete the denitrification process. This modelling study investigates in detail the relationship between the denitrification process in natural soils, with excess and in limitation of organic substrates, and the occurrence and fate of dissolved dinitrogen analysed with a high precision membrane inlet mass spectrometer. Results demonstrate that modelling nitrate degradation processes as a whole, using geochemical datasets and codes, will improve the estimates of agricultural landscapes denitrification and support better nitrogen management, especially in lowland environments.
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J. Donnini, G. Chiappini, G. Lancioni, V. Corinaldesi, “Tensile behaviour of glass FRCM systems with fabrics’ overlap: Experimental results and numerical modelling”, Composite Structures, 212 (March), 2019, 398-411
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Abstract:
The use of Fabric Reinforced Cementitious Matrix (FRCM) systems to reinforce existing masonry and concrete structures is nowadays a well-established practice. The mechanical characterization of FRCM systems is of fundamental importance to define the correct parameters needed to design a strengthening intervention. However, some aspects regarding FRCM tensile behaviour need to be further investigated. The aim of this paper is to provide a detailed overview on the mechanical behaviour of FRCM specimens subjected to tensile tests. In this context, the effect of fabrics’ overlapping on the global behaviour of the system is extensively analyzed. Different sample’s configurations have been studied: one reinforced with a single layer of bidirectional glass fabric and three others with different fabrics’ overlap lengths, varying between 100 and 200 mm. Digital Image Correlation (DIC) has been also used to measure displacements in experimental testing. A phase-field model, that accounts for brittle fracture of cementitious matrix and fabric reinforcement and possible slippage at the fabric-to-matrix interface, has been developed. The variational formulation has been implemented in a finite element code to simulate the tensile behaviour of FRCM systems and the effects of using different fabrics’ overlap lengths.
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J. Donnini, S. Spagnuolo, V. Corinaldesi, “A comparison between the use of FRP, FRCM and HPM for concrete confinement”, Composites Part B: Engineering, 160(March), 2019, Pages 586-594
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Abstract:
The use of new methods to strengthen and rehabilitate existing concrete and masonry structures is one of the challenges that the engineering community is facing in recent years. In this field, composite materials are acquiring more and more success, due to lower invasiveness and ease of application if compared to more traditional systems (e.g. steel plates or reinforced concrete jacketing). This work, based on experimental investigations, aims to propose a comparison between three different methods as possible strengthening solutions for existing concrete elements. Twenty compression tests were conducted on reduced scale concrete columns, realized by using a low performance concrete, in order to reproduce the poor mechanical properties of most existing structures. Two of them were left unconfined, while the other ones were reinforced by using Fiber Reinforced Polymer (FRP), Fiber Reinforced Cementitious Matrix (FRCM) or High Performance Mortar (HPM) systems. The effectiveness of the different strengthening techniques and the main differences in terms of structural response were investigated. Experimental results were then compared with predictions deriving from guidelines and theoretical models from the literature.
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M. Mandolini, A. Brunzini, M. Germani, S. Manieri, A. Mazzoli, M. Pagnoni, “Selective laser sintered mould for orbital cavity reconstruction”, Rapid Prototyping Journal, Vol. 25, Issue 1, 2019, 95-103.
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Abstract:
Purpose: Orbital fractures are the most commonly encountered midfacial fractures, and usually, the fracture involves the floor and/or the medial wall of the orbit. This paper aims to present an innovative approach for primary and secondary reconstructions of fractured orbital walls through the use of computer-assisted techniques and additive manufacturing. Design/methodology/approach: First, through the 3D anatomical modelling, the geometry of the implant is shaped to fill the orbital defect and recover the facial symmetry. Subsequently, starting from the modelled implant, a customised mould is designed taking into account medical and technological requirements. Findings: The selective laser sintered mould is able to model and form several kind of prosthetic materials (e.g. titanium meshes and demineralised bone tissue), resulting in customised implants and allowing accurate orbital cavity reconstructions. The case study proved that this procedure, at the same time, reduces the morbidity on the patients, the duration of surgery and the related costs. Originality/value: This innovative approach has great potential, as it is an easy and in-office procedure, and it offers several advantages over other existing methods.
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Corinaldesi, C., Rastelli, E., Canensi, S., Tangherlini, M., Danovaro, R., &Dell’Anno, A. High rates of viral lysis stimulate prokaryotic turnover and C recycling in bathypelagic waters of a Ligurian canyon (Mediterranean Sea). 2019. Progress in Oceanography, 171, 70-75.
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Abstract:
Submarine canyons are able to preferentially channel primary production and shelf export to the deep ocean, thus acting as hotspots of biomass and biogeochemical cycling of organic matter. Despite their global relevance, no information is available about the influence of submarine canyons on deep-sea virus-prokaryote interactions. Here, we show that deep-sea waters overlying the Bisagno Canyon (Ligurian Sea, NW Mediterranean) can sustain up to 4 times higher abundances of bathypelagic prokaryotes and viruses when compared to the waters overlying the adjacent slope. We also report that the bathypelagic waters of the canyon are hotspots of viral infections, with rates of virus-induced prokaryotic mortality and biomass turnover up to 10 times faster compared to the adjacent slope at similar depths. In addition, C released by viral lysis of their prokaryotic hosts in bathypelagic waters of the canyon was up to 40 times higher than in the slope. The prokaryotic distribution in bathypelagic waters of the investigated area of the Ligurian margin was largely influenced by organic C concentrations and temperature. Our results highlight that the peculiar characteristics of the canyons (such as the Bisagno canyon) could contribute to sustain the metabolism of bathypelagic prokaryotes, promoting C cycling through virus-induced prokaryotic mortality. We conclude that submarine canyons could represent hot spots of prokaryotic and viral activities able to support the deep-sea pelagic food webs.
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Corinaldesi, C., Tangherlini, M., Rastelli, E., Buschi, E., Martire, M. L., Danovaro, R., &Dell’Anno, A. High diversity of benthic bacterial and archaeal assemblages in deep-Mediterranean canyons and adjacent slopes. 2019. Progress in Oceanography, 171, 154-161.
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Abstract:
Submarine canyons and slopes increase the topographic heterogeneity of continental margins and enhance mass and energy transfer from the shelf to the deeper basins, profoundly influencing the biodiversity and functioning of deep-sea ecosystems. However, information on the distribution and diversity of microbial assemblages in such habitats is extremely scant. In the present study, for the first time, we investigated abundances of benthic prokaryotes and their diversity (i.e., bacterial and archaeal) in two of the largest canyons of the Mediterranean Sea (Bisagno and Polcevera Canyons, in the Ligurian Margin) and their adjacent open slope along a water-depth gradient from 200 to 2000 m. We found that prokaryotic abundance and the richness of Operational Taxonomic Units (OTUs) varied within a narrow range despite the high variability of thermohaline and trophic conditions in the habitats investigated. Conversely, the taxonomic composition (in terms of OTUs) was highly variable among the different habitats and depths investigated. The largest fraction of OTUs (representing >80% of the total OTUs identified) were unique of each sampling site, indicating a high prokaryotic β-diversity among the investigated systems. Thermo-haline and trophic conditions and water depth only partially influenced the composition of the prokaryotic assemblages suggesting that other factors, potentially related to physical forcing typically occurring in margin ecosystems, could promote a high diversification of benthic bacterial and archaeal assemblages. This study provides new insights into the benthic prokaryotic diversity of Ligurian canyons and suggests that microbial assemblages thriving in continental margins can largely contribute to the whole diversity of Mediterranean deep-sea ecosystems.
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