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M. Pisani, L. Quassinti, M. Bramucci, R. Galassi, F. Maggi, B. Rossi, A. Damin, P. Carloni, P. Astolfi, “Nanostructured liquid crystalline particles as delivery vectors for isofuranodiene: Characterization and in-vitro anticancer activity”, Colloids and Surfaces B, Biointerfaces 192, 2020, 111050
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Abstract:
Isofuranodiene is an oxygenated sesquiterpene containing a furan ring isolated from the essential oil of Smyrnium olusatrum L. (Apiaceae) owning notable anticancer activity. Despite its biological potential, the high lipophilicity along with a relatively low stability due to Cope rearrangement giving rise to a less active compound, make the perspective of its therapeutical use unlikely. On this basis, in the present work we evaluated bulk and dispersed non lamellar liquid crystalline phases as effective delivery vectors for isofuranodiene, and capable of preserving its structure and enhancing the biological activity. Small-angle X-ray scattering, dynamic light scattering, and UV resonance Raman spectroscopy were used to characterize the nanosystems in an integrated experimental approach. Encapsulation of isofuranodiene in the lipid matrix resulted in a transition from a cubic Im3m to a reversed hexagonal phase because of the highly lipophilic character of the drug, as obtained in SAXS measurements, and in significant shifts in the components of the Raman spectrum of isofuranodiene. The anticancer activity of isofuranodiene-loaded lipidic nanoparticles was assessed on MDA-MB 231 cell line by MTT assay and was found to be higher than that of pristine isofuranodiene.
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V. Notarstefano, S. Sabbatini, C. Conti, M. Pisani, P. Astolfi, C. Pro, C. Rubini, L. Vaccari, E. Giorgini, “Investigation of human pancreatic cancer tissues by Fourier Transform Infrared Hyperspectral Imaging”, Journal of Biophotonics 13, 2020, e201960071
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Abstract:
Fourier‐transform infrared hyperspectral imaging (FTIR‐HSI) provides hyperspectral images containing both morphological and chemical information. It is widely applied in the biomedical field to detect tumor lesions, even at the early stage, by identifying specific spectral biomarkers. Pancreatic neoplasms present different prognoses and are not always easily classified by conventional analyses. In this study, tissue samples with diagnosis of pancreatic ductal adenocarcinoma and pancreatic neuroendocrine tumor were analyzed by FTIR‐HSI and the spectral data compared with those from healthy and dysplastic samples. Multivariate/univariate approaches were complemented to hyperspectral images, and definite spectral markers of the different lesions identified. The malignant lesions were recognizable both from healthy/dysplastic pancreatic tissues (high values of phospholipids and triglycerides with shorter, more branched and less unsaturated alkyl chains) and between each other (different amounts of total lipids, phosphates and carbohydrates). These findings highlight different metabolic pathways characterizing the different samples, well detectable by FTIR‐HSI.
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M. Di Sante, “On the Compaction Characteristics of Soil-Lime Mixtures”, Geotech. Geol. Eng., 38(2), 2020, 2335-2344 DOI 10.1007/s10706-019-01110-w
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Aim of the present note is to contribute to the optimization of the mix-design procedure of lime treated soils with particular reference to compaction characteristics. Seven soils with different plasticity characteristics and clay fractions are included in the experimental program, different amounts of quicklime and hydrated lime were added to the soils by wet mixing and then Standard Proctor compaction was carried out at different water contents in order to study the effect of lime treatment on compaction characteristics. Microstructural investigation was developed by means of scanning electron microscope. A general decrease in the maximum dry unit weight was observed together with a flattening of the Proctor curve. Also optimum water content changes due to lime addition. A factor that takes into account these modifications was defined and compared for several mix designs. Good correlations (confirmed by Fisher’s statistical test) between this factor and clay fractions of the soil to be treated were derived for 5% hydrated lime added. In addition, useful directions were retrieved analysing experimental results for soils treated with different types of lime in different proportions. Results contribute to have a preliminary idea of the effective mix design parameters, knowing the soil to be treated, helping, in this way, in possibly reducing the number of tests in the design phase.
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C. Minnelli, E. Laudadio, R. Galeazzi, G. Barucca, V. Notarstefano, M. Cantarini, T. Armeni, G. Mobbili “Encapsulation of a Neutral Molecule into a Cationic Clay Material: Structural Insight and Cytotoxicity of Resveratrol/Layered Double Hydroxide/BSA Nanocomposites”, Nanomaterials 2020, 10, 33
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Abstract:
Non-small cell lung cancer (NSCLC) represents a di_cult condition to treat, due to epidermal growth factor receptor (EGFR) kinase domain mutations, which lead to ligand-independent phosphorylation. Deletion of five amino acids (ELREA) in exon 19 and mutational change from leucine to arginine at position 858 (L858R) are responsible for tyrosine kinase domain aberrant activation. These two common types of EGFR-mutated forms are clinically associated with high response with Tyrosine Kinase Inhibitors (TKI); however, the secondary T790M mutation within the Tyrosine Kinase Domain (TKD) determines a resistance to these EGFR-TKIs. Using molecular dynamic simulation (MD), the present study investigated the architectural changes of wild-type and mutants EGFR’s kinase domains in order to detect any conformational differences that could be associated with a constitutively activated state and thus to evaluate the differences between the wild-type and its mutated forms. In addition, in order to evaluate to which extent the EGFR mutations affect its inhibition, Epigallocatechin 3-Gallate (EGCG) and Erlotinib (Erl), known EGFR-TKI, were included in our study. Their binding modes with the EGFR-TK domain were elucidated and the binding differences between EGFR wild-type and the mutated forms were evidenced. The aminoacids mutations directly influence the binding a_nity of these two inhibitors, resulting in a different efficacy of Erl and EGCG inhibition. In particular, for the T790M/L858R EGFR, the binding modes of studied inhibitors were compromised by aminoacidic substitution confirming the experimental findings. These results may be useful for novel drug design strategies targeting the dimerization domain of the EGFR mutated forms, thus preventing receptor activation.
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Castagna, R., Lucchetta, D.E., Rippa, M., Xu, J.-H., Donato, A.D. “Near-frequency photons Y-splitter” (2020) Applied Materials Today, 19, art. no. 100636
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We are reporting on a wavelength-controlled anomalous angular light scattering with a very high spatial angular dispersion in correspondence to a very small frequencies range. Essentially, we present a device able to Y-split in-air wavelengths of a laser beam few tens of nanometers away from each other. We explain its working mechanism through Moirè-interactions between structured-light and all-dielectric matter structured by light. More precisely, we ascribe this effect to Moiré-beats between holographic patterns recorded in a material and a spatially modulated wave-front of a probe-beam with slightly different spatial frequency content. © 2020
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S.L. Shafforz, G. Nordendorf, G. Nava, L. Lucchetti, A. Lorenz, “Formation of relocatable umbilics in a liquid crystal with positive dielectric anisotropy induced via photovoltaic fields”, J. of Molecular Liquids, 307, 112963 (2020)
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Abstract:
All optically generated, relocatable umbilic defects in a liquid crystal (LC) with positive dielectric anisotropy are reported. The studied samples are made with a Fe-doped LiNbO3 substrate showing the bulk photovoltaic effect and an ITO coated glass plate as covering substrate. Umbilics are created upon exposure with a focused laser beam: they are induced via photo generated fields at the relocatable exposure beam position. The distribution of these fields is normal to the sample plane at the exposure spot centre and has increasingly high in-plane field components in radial direction: ideal conditions to induce director reorientation with radial symmetry in a LC with positive dielectric anisotropy. The irradiated regions are studied with polarized probe light revealing the characteristic for umbilic defects and the typical doughnut-shaped intensity distributions expected for optical vortex beams. The experimental findings are compared to calculated transmission profiles. Moreover, a LC with negative dielectric anisotropy was studied in the same type of sample for reference.
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R Danovaro, E Fanelli, M Canals, T Ciuffardi, M-C Fabri, M Taviani, M Argyrou, E Azzurro, S Bianchelli, A Cantafaro, L Carugati, C Corinaldesi et alii (2020) “Towards a marine strategy for the deep Mediterranean Sea: Analysis of current ecological status” Mar. Policy, 112 (February), 2020, 103781.
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Abstract:
The Marine Strategy Framework Directive (MSFD), introduced in June 2008, was adopted to achieve a Good Environmental Status (GES) in the EU's marine waters and to protect resources of socio-economic interest. The MSFD exerts to the marine area over which a Member State exercises jurisdictional rights in accordance with the United Nations Convention on the Law of the Sea (UNCLOS), including the deep-sea waters, seafloor and sub-seafloor of the Exclusive Economic Zones (EEZ). However, currently the MSFD focuses on coastal habitats and the shallow-water seafloor to the detriment of the deeper habitats. Despite the huge dimension of the deep sea (below 200 m of depth) covering more than 65% of the Earth's surface and including >95% of the global biosphere, the relevance of the dark portion of the seas and oceans is still almost completely neglected. Given the important bi-directional links between shallow and deep ecosystems, there is a clear need for extending the implementation of the MSFD into the deep sea, to define a sound ecosystem-based approach for the management and protection of deep-sea ecosystems and attain GES. We assembled data on drivers, anthropogenic pressures and impacts concerning the MSFD descriptors pertaining to the Mediterranean deep sea. We list deep-sea monitoring activities and the main sources providing benchmark conditions, and discuss knowledge and geographic coverage gaps. MSFD descriptors apply to the deep sea as to coastal waters, and ought to be monitored contemporaneously. We provide recommendations for guidelines for future deep-sea monitoring in the Mediterranean Sea.
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Varrella, S., Tangherlini, M., & Corinaldesi, C “Deep Hypersaline Anoxic Basins as Untapped Reservoir of Polyextremophilic Prokaryotes of Biotechnological Interest” Marine drugs, 18 (January), 2020, 91
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Deep-sea hypersaline anoxic basins (DHABs) are considered to be among the most extreme ecosystems on our planet, allowing only the life of polyextremophilic organisms. DHABs’ prokaryotes exhibit extraordinary metabolic capabilities, representing a hot topic for microbiologists and biotechnologists. These are a source of enzymes and new secondary metabolites with valuable applications in different biotechnological fields. Here, we review the current knowledge on prokaryotic diversity in DHABs, highlighting the biotechnological applications of identified taxa and isolated species. The discovery of new species and molecules from these ecosystems is expanding our understanding of life limits and is expected to have a strong impact on biotechnological applications.
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Danovaro, R., Fanelli, E., Aguzzi, J., Billett, D., Carugati, L., Corinaldesi, C., … & McClain, C. All authors contributed equally. “Ecological variables for developing a global deep-ocean monitoring and conservation strategy", Nature Ecol Evol, 4 (January), 2020, 181-192.
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Abstract:
The deep sea (>200 m depth) encompasses >95% of the world’s ocean volume and represents the largest and least explored biome on Earth (<0.0001% of ocean surface), yet is increasingly under threat from multiple direct and indirect anthropogenic pressures. Our ability to preserve both benthic and pelagic deep-sea ecosystems depends upon effective ecosystem-based management strategies and monitoring based on widely agreed deep-sea ecological variables. Here, we identify a set of deep-sea essential ecological variables among five scientific areas of the deep ocean: (1) biodiversity; (2) ecosystem functions; (3) impacts and risk assessment; (4) climate change, adaptation and evolution; and (5) ecosystem conservation. Conducting an expert elicitation (1,155 deep-sea scientists consulted and 112 respondents), our analysis indicates a wide consensus amongst deep-sea experts that monitoring should prioritize large organisms (that is, macro- and megafauna) living in deep waters and in benthic habitats, whereas monitoring of ecosystem functioning should focus on trophic structure and biomass production. Habitat degradation and recovery rates are identified as crucial features for monitoring deep-sea ecosystem health, while global climate change will likely shift bathymetric distributions and cause local extinction in deep-sea species. Finally, deep-sea conservation efforts should focus primarily on vulnerable marine ecosystems and habitat-forming species. Deep-sea observation efforts that prioritize these variables will help to support the implementation of effective management strategies on a global scale.
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Rastelli, E., Petani, B., Corinaldesi, C., Dell’Anno, A., Martire, M. L., Cerrano, C., & Danovaro, R. “A high biodiversity mitigates the impact of ocean acidification on hard-bottom ecosystems”, Sci Rep. 10 (February), 2020, 1-13.
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Abstract:
Biodiversity loss and climate change simultaneously threaten marine ecosystems, yet their interactions remain largely unknown. Ocean acidification severely affects a wide variety of marine organisms and recent studies have predicted major impacts at the pH conditions expected for 2100. However, despite the renowned interdependence between biodiversity and ecosystem functioning, the hypothesis that the species’ response to ocean acidification could differ based on the biodiversity of the natural multispecies assemblages in which they live remains untested. Here, using experimentally controlled conditions, we investigated the impact of acidification on key habitat-forming organisms (including corals, sponges and macroalgae) and associated microbes in hard-bottom assemblages characterised by different biodiversity levels. Our results indicate that, at higher biodiversity, the impact of acidification on otherwise highly vulnerable key organisms can be reduced by 50 to >90%, depending on the species. Here we show that such a positive effect of a higher biodiversity can be associated with higher availability of food resources and healthy microbe-host associations, overall increasing host resistance to acidification, while contrasting harmful outbreaks of opportunistic microbes. Given the climate change scenarios predicted for the future, we conclude that biodiversity conservation of hard-bottom ecosystems is fundamental also for mitigating the impacts of ocean acidification.
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Hiraoka, S., Hirai, M., Matsui, Y., Makabe, A., Minegishi, H., Tsuda, M. Juliarni, Rastelli, E., Danovaro, R., Corinaldesi, C., … & Tasumi, E. (2020). "Microbial community and geochemical analyses of trans-trench sediments for understanding the roles of hadal environments". ISME J, 14(March), 2020, 740-756.
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Abstract:
Hadal trench bottom (>6000 m below sea level) sediments harbor higher microbial cell abundance compared with adjacent abyssal plain sediments. This is supported by the accumulation of sedimentary organic matter (OM), facilitated by trench topography. However, the distribution of benthic microbes in different trench systems has not been well explored yet. Here, we carried out small subunit ribosomal RNA gene tag sequencing for 92 sediment subsamples of seven abyssal and seven hadal sediment cores collected from three trench regions in the northwest Pacific Ocean: the Japan, Izu-Ogasawara, and Mariana Trenches. Tag-sequencing analyses showed specific distribution patterns of several phyla associated with oxygen and nitrate. The community structure was distinct between abyssal and hadal sediments, following geographic locations and factors represented by sediment depth. Co-occurrence network revealed six potential prokaryotic consortia that covaried across regions. Our results further support that the OM cycle is driven by hadal currents and/or rapid burial shapes microbial community structures at trench bottom sites, in addition to vertical deposition from the surface ocean. Our trans-trench analysis highlights intra- and inter-trench distributions of microbial assemblages and geochemistry in surface seafloor sediments, providing novel insights into ultradeep-sea microbial ecology, one of the last frontiers on our planet.
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Gambi, C., Dell’Anno, A., Corinaldesi, C., Martire, M. L., Musco, L., Da Ros, Z., … & Danovaro, R. "Impact of historical contamination on meiofaunal assemblages: the case study of the Bagnoli-Coroglio Bay (Southern Tyrrhenian Sea)". Mar Envir Res. 156 (April), 2020, 104907.
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Abstract:
The effects of contaminants on marine organisms have been documented since decades, but the long-term responses and recovery rates of benthic communities to mixtures of contaminants, several years after the cessation of industrial activities, need to be further investigated. Bagnoli-Coroglio Bay (Gulf of Naples, Tyrrhenian Sea) is a typical example of historically contaminated coastal area due to industrial activities stopped at the beginning of nineties. In the present study we carried out a fine spatial scale analysis of the distribution of meiofaunal (and nematodes) assemblages along five bathymetric transects located at increasing distance from the historical source of contamination in relation with the polycyclic aromatic hydrocarbon and heavy metal concentrations present in the sediment. Meiofaunal abundance and biomass changed widely along transects but independent from the distance from the source of contamination. Even when the contamination levels were expected to induce significant detrimental biological consequences, meiofaunal abundance and biomass were similar to those reported in unpolluted benthic coastal areas worldwide. Conversely, biodiversity in terms of meiofaunal taxa richness was generally low (range: 5–8 taxa in 12 of the overall 15 stations investigated). This was explained by the lack of sensitive groups such as ostracods, gastrotrichs and tardigrades commonly encountered in benthic coastal ecosystems, thus reflecting an overall poor/moderate environmental quality of the investigated area. Nematode (structural and functional) diversity was also low, particularly at stations characterized by higher contamination levels. At the same time, nematode species composition did not change significantly among stations suggesting a widespread effect of contaminants able to reduce the variability (i.e., turnover diversity) within the assemblages of the whole study area. Overall, our results indicate that even decades after the cessation of contaminant emissions, benthic biodiversity was affected in terms of both meiofaunal taxa and nematode species. These findings strongly reinforce the call for reducing sources of chronic pollution in marine ecosystems and provide new insights for a better understanding of the ecological recovery of historically contaminated marine environments.
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Sfriso, A. A., Tomio, Y., Rosso, B., Gambaro, A., Sfriso, A., Corami, F., Rastelli, E, Corinaldesi, C., … & Munari, C. "Microplastic accumulation in benthic invertebrates in Terra Nova Bay (Ross Sea, Antarctica)". Environment International, 2020, 137 (April), 105587.
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Abstract:
Microplastic contamination of the benthic invertebrate fauna in Terra Nova Bay (Ross Sea, Antarctica) was determined. Twelve macrobenthic species, characterized by different feeding strategies, were selected at 3 sampling sites at increasing distance from the Italian Scientific Base (Mario Zucchelli, Camp Icarus, Adelie Cove). The 83% of the analyzed macrobenthic species contained microplastics (0.01–3.29 items mg−1). The size of the particles, measured by Feret diameter, ranged from 33 to 1000 µm with the highest relative abundance between 50 and 100 µm. Filter-feeders and grazers displayed values of microplastic contamination from 3 to 5 times higher than omnivores and predators, leading to the hypothesis that there is no evident bioaccumulation through the food web. The prevalent polymers identified by micro-FTIR were nylon (86%) and polyethylene (5%); other polymers identified in Antarctic benthos were polytetrafluoroethylene, polyoxymethylene, phenolic resin, polypropylene, polystyrene resin and XT polymer.
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Akyol, Ç., Foglia, A., Ozbayram, E.G., Frison, N., Katsou, E., Eusebi, A.L.*, Fatone, F., 2020, Validated innovative approaches for energy-efficient resource recovery and re-use from municipal wastewater: From anaerobic treatment systems to a biorefinery concept, Critical Reviews in Environmental Science and Technology, Volume 50, Issue 9, Pages 869-902
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Abstract:
The development of innovative technologies in wastewater treatment create the concept of biorefinery in wastewater treatment plants (WWTPs), placing anaerobic processes in the highlight. Starting from the conventional anaerobic treatment processes to ‘closing the loop’ scheme, next generation WWTPs are ready to serve for water, energy and materials mining. While bioenergy is still dominating the resource recovery, recovery of value-added materials (i.e. struvite, biopolymers, cellulose) are receiving significant attention in recent years. So, what are the state-of-the-art approaches for energy-efficient resource recovery and re-use from municipal wastewater? This paper follows a critical review on the validated technologies in operational environment available and further suggests possible market routes for the recovered materials in WWTPs. Considering the development and verification of a novel technology together with the valorization of the obtained products, biorefinery and resource recovery approaches were gathered in this review paper from a circular economy point of view. General currently-faced barriers were briefly addressed to pave the way to create to-the-point establishments of resource recovery facilities in the future.
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| Da Ros, C., Conca, V., Eusebi, A.L., Frison, N., Fatone, F., 2020, Sieving of municipal wastewater and recovery of bio-based volatile fatty acids at pilot scale, Water Research, Volume 174, 115633 |
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Abstract:
This study combined at pilot scale the recovery of cellulosic primary sludge from the sieving of municipal wastewater followed by the production of bio-based VFAs through acidogenic fermentation. The sieving of municipal wastewater was accomplished by a rotating belt filter which allowed the removal of around 50% of suspended solids when operated at solids loading rates higher than 30–35 kgTSS/m2 h. The solids recovered by sieving contained around 40% of cellulose, which is a suitable raw material for the production of bio-based VFAs. Initially, fermentation batch tests of cellulosic primary sludge were carried out adjusting the initial pH of the sludge at values of 8, 9, 10 and 11, in order to evaluate the best production yields of bio-based VFAs and their composition. The highest VFAs yield achieved was 521 mgCODVFA/gVS occurring when pH was adjusted at 9, while propionic acid reached 51% of the total VFAs. Then, the optimal conditions were applied at long term in a sequencing batch fermentation reactor where the highest potential productivity of bio-based VFAs (2.57 kg COD/m3 d) was obtained by adjusting the pH feeding at 9 and operating with an hydraulic retention time of 6 days under mesophilic conditions. The cost-benefit analyses for the implementation of cellulosic primary sludge recovery was carried out consideringthe anaerobic digestion as reference scenario. The economical assessment showed that the production of bio-based VFAs from cellulosic primary sludge as carbon source and/or as chemical precursors give higher net benefits instead of the only biogas production.
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| A. Foglia, C. Akyol, N. Frison, E. Katsou, A.L. Eusebi, F. Fatone, 2020, Long-term operation of a pilot-scale anaerobic membrane bioreactor (AnMBR) treating high salinity low loaded municipal wastewater in real environment, Separation and Purification Technology, Volume 236, 116279 |
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Abstract:
Long term operation of an anaerobic membrane bioreactor (AnMBR) treating municipal wastewater was investigated in a real seawater intrusion spot in Falconara Marittima (Central Italy) on the Adriatic coastline. Changes in biological conversion and system stability were determined with respect to varying organic loading rate (OLR) and high salinity conditions. At an OLR of 1 kg COD m3−1 d−1, biogas production was around 0.39 ± 0.2 L d−1. The increase of the OLR to 2 kg COD m3−1 d−1 resulted in increase of biogas production to 2.8 ± 1.5 L d−1 (with 33.6% ± 10.5% of CH4) with methanol addition and to 4.11 ± 3.1 L d−1 (with 29.7% ± 11.8% of CH4) with fermented cellulosic sludge addition. COD removal by the AnMBR was 83% ± 1% when the effluent COD concentration was below 100 mg O2 L−1. The addition of the fermented sludge affected the membrane operation and significant fouling occurred after long-term filtration, where the trans-membrane pressure (TMP) reached up to 500 mbar. Citric acid solution was applied to remove scalants and the TMP reached the initial value. High saline conditions of 1500 mgCl− L−1 adversely affected the biogas production without deteriorating the membrane operation. The treated effluent met the EU quality standards of the D.M. 185/2003 and the new European Commission Resolution for reuse in agriculture
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| A. Botturi, S. Daneshgar, A. Cordioli, A. Foglia, A.L. Eusebi*, F. Fatone, 2020, An innovative compact system for advanced treatment of combined sewer overflows (CSOs) discharged into large lakes: Pilot-scale validation, Journal of Environmental Management, Volume 256, 109937 |
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Abstract:
Combined sewer overflows discharging into natural water bodies could potentially contaminate them in terms of conventional wastewater parameters and coliform bacteria. When green water infrastructures are not technically feasible or practically sustainable for stormwater management, innovative compact and effective end-of-pipe systems can be of interest. This study presents long-term and real-environment validated data of a compact and rapid treatment system specifically applicable to CSOs that consists of a dynamic rotating belt filter, adsorption on granular activated carbon and UV disinfection steps. The results of treatment for Lake Garda in Italy, showed great potential for TSS, COD and E. coli removal efficiencies with more than 90%, 69% and 99% respectively. Due to the short contact time of GAC adsorption, nutrients removals were not very high. TN and TP removal of around 41% and 19% were observed respectively that suggests further specific nutrients removal processes are required for achieving higher efficiencies. The treatment system, due to its compactness and rapidness could be a great asset for water utilities in different EU catchments that are dealing with the frequent CSO events. In addition, the possibility of using different combinations of treatment steps allows the choice of different treatment scenarios depending on the treatment goals for any specific catchment.
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| F. Battista, N. Frison, C. Cavinato, M. Gottardo, A.L. Eusebi, F. Fatone, M. Majone, M. Zeppilli, P. Pavan, D. Bolzonella, 2020, Food wastes and sewage sludge as feedstock for an urban biorefinery producing biofuels and added value bio-products, Journal of Chemical Technology and Biotechnology, Volume 95, 2, 328-338 |
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Abstract:
The updated Bioeconomy Strategy document “A sustainable bioeconomy for Europe: strengthening the connection between economy, society and the environment”, which was issued by the European Commission in October 2018, encourages the exploitation of organic wastes according to a pyramidal hierarchy in which the extraction of valuable biomolecules, which will be used as they are or as precursors of high-added-value compounds, is a priority in biofuel production. This review considers a biorefinery platform in which food waste and sewage sludge are adopted to produce volatile fatty acids (VFAs) through a dark fermentation process. VFA fermentation is optimized by slightly acid pH (6–7), short hydraulic retention time (1–7 days) and high organic load rate (more than 10 gTS L−1 d−1). Attention has been focused on VFA exploitation for polyhydroxyalkanoate (PHA) production via a ‘feast and famine’ strategy performed in sequencing batch reactors. The obtained PHA yields are around 0.4–0.5 gPHA gCOD−1. Moreover, VFAs allow for the production of biofuels, such as hydrogen and methane, through single- or double-staged anaerobic digestion. Innovative bioelectrochemical upgrade strategies for biogas helps producers to obtain biomethane for the automotive sector. Moreover, biogas has recently been tested for the production of polyhydroxybutyrate, a biodegradable and biocompatible thermoplastic made by microorganisms from C1 carbon sources (CO2 and CH4). Digestates from anaerobic bioreactors are still rich in nitrogen and phosphorus compounds. These latter compounds have been identified as critical raw materials due to their low availability in the European Union and to increasing demand from the growing global population. Thus, nutrient recovery from digestate allows users to close the loop of the ‘circular economy’ approach.
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| Szeląg, B., Drewnowski, J., Łagód, G., Majerek, D., Dacewicz, E., Fatone, F.Soft sensor application in identification of the activated sludge bulking considering the technological and economical aspects of smart systems functioning. Sensors (Switzerland) Volume 20, Issue 7, 1 April 2020, Article number 1941. |
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Abstract:
The paper presented the methodology for the construction of a soft sensor used for activated sludge bulking identification. Devising such solutions fits within the current trends and development of a smart system and infrastructure within smart cities. In order to optimize the selection of the data-mining method depending on the data collected within a wastewater treatment plant (WWTP), a number of methods were considered, including: artificial neural networks, support vector machines, random forests, boosted trees, and logistic regression. The analysis conducted sought the combinations of independent variables for which the devised soft sensor is characterized with high accuracy and at a relatively low cost of determination. With the measurement results pertaining to the quantity and quality of wastewater as well as the temperature in the activated sludge chambers, a good fit can be achieved with the boosted trees method. In order to simplify the selection of an optimal method for the identification of activated sludge bulking depending on the model requirements and the data collected within the WWTP, an original system of weight estimation was proposed, enabling a reduction in the number of independent variables in a model— quantity and quality of wastewater, operational parameters, and the cost of conducting measurements.
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| Benedetti, B., Majone, M., Cavaliere, C., Montone, C.M., Fatone, F., Frison, N., Laganà, A., Capriotti, A.L. Determination of multi-class emerging contaminants in sludge and recovery materials from waste water treatment plants: Development of a modified QuEChERS method coupled to LC–MS/MS. Microchemical Journal Volume 155, June 2020, Article number 104732 |
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Abstract:
Recycling and recovering valuable resources from wastewater treatment plants is an important aspect in circular economy. The safe use of sludge and sludge-related products deriving from wastewater treatment strictly depends on their chemical contamination, especially by emerging pollutants. In this work, an analytical method was developed for the determination of a range of selected compounds, included in a recent European watch-list (macrolides, fluoroquinolones, neonicotinoids, carbamates and estrogens), in recovery materials from innovative pilot systems. Both the instrumental analysis by high-performance liquid chromatography-tandem mass spectrometry and the pre-treatment strategy (quick, easy, cheap, effective, rugged and safe technique) were optimized for the purpose. The final method performance were evaluated, revealing determination coefficients (R2) of 0.993–0.9999 for the matrix-matched calibration curves, good accuracy (recovery 68–104% and matrix effect 70–123%), satisfactory precision (relative standard deviation <20%) and limits of detection and quantitation in the low ng g−1 levels. Ten different recovery material samples were analyzed, showing contamination by few analytes, mainly antibiotics and estrone; ciprofloxacin and azithromycin were the most abundant compounds (up to 500–600 ng g−1). On the contrary, neonicotinoid pesticides were not detected, except for one sample (sample 10, the only compost material). The application of the described method is an essential part of a broader investigation on the suitability and safety of innovative materials coming from waste water treatment plants, in the view of a risk assessment related to their usage.
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| P. Ruggeri, V. M. E. Fruzzetti, G. Scarpelli, “Upgrading of quay walls at the Ravenna port, Italy: evaluation of the steel piles degradation after a long working life”, Structure and Infrastructure Engineering, (March, published online), 2020 – https://doi.org/10.1080/15732479.2020.1736101 |
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Abstract:
In the context of a challenging project aimed at the upgrading of some old quays in the port of Ravenna (Italy) an extensive survey was conducted to determine the level of degradation of the most significative structural elements. The quays were essentially constituted by anchored sheet pile retaining walls in which the main structural elements were steel profiles. Therefore, the main point of concern was the degradation of the steel piles after a long-lasting exposure to the sea water. The corrosion of steel structures in marine environment is a well-recognized problem for maritime engineering, therefore nowadays a relevant part of the designing effort is oriented towards improving the durability and to minimize the cost of maintenance of infrastructures. However, data from real experience are not frequent. This paper presents some results of the inspection carried out on quays in the Ravenna port after an operative life between 21 to 29 years, focusing on the condition of the steel piles. Data include ultrasonic measurements of the thickness and laboratory analyses of steel samples. Although the environmental conditions were not particularly favourable, the results indicate that the degradation of the profiles in the permanently immersed zone was very limited.
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| Gabriele Micheletti, Carla Boga,* Dario Telese, Maria Cristina Cassani, Elisa Boanini, Patrizia Nitti, Barbara Ballarin, Alberto Ghirri, Gianni Barucca, and Daniele Rinaldi* “Magnetic Nanoparticles Coated with (R)‐9-Acetoxystearic Acid for Biomedical Applications”, ACS Omega 2020, 5, 22, 12707–12715 https://dx.doi.org/10.1021/acsomega.0c00163 |
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Abstract:
The well-known ability to selectively drive nano- magnetic materials coated with anticancer drugs into tumor cells suggested the synthesis and the characterization of magnetic nanoparticles (MNPs) functionalized with (R)-9-acetoxystearic acid, the acetic ester of (R)-9-hydroxystearic acid (9-HSA), an antiproliferative agent active against different cancer cells. The acyl chloride of (R)-9-acetoxystearic acid, synthesized in two steps from 9-HSA, was reacted with (3-aminopropyl)triethoxysilane, chosen as a linker between MNPs and the stearyl moiety. In the last step, the novel amide was bound to magnetite NPs by reaction with silyl groups. A detailed structural, chemical, and magnetic character- ization of the obtained material proved that it possesses properties in agreement with the requirements for drug delivery, opening the possibility to further insights focused on the 9-HSA biomedical applications.
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| Schultz MD, Dadali T, Jacques SA, Muller-Steffner H, Foote JB, Sorci L, Kellenberger E, Botta D, Lund FE. Inhibition of the NAD salvage pathway in schistosomes impairs metabolism, reproduction, and parasite survival. PLoS Pathog., 16 (May), 2020, e1008539. |
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Abstract:
NAD, a key co-enzyme required for cell metabolism, is synthesized via two pathways in most organisms. Since schistosomes apparently lack enzymes required for de novo NAD biosynthesis, we evaluated whether these parasites, which infect >200 million people worldwide, maintain NAD homeostasis via the NAD salvage biosynthetic pathway. We found that intracellular NAD levels decline in schistosomes treated with drugs that block production of nicotinamide or nicotinamide mononucleotide-known NAD precursors in the non-deamidating salvage pathway. Moreover, in vitro inhibition of the NAD salvage pathway in schistosomes impaired egg production, disrupted the outer membranes of both immature and mature parasites and caused loss of mobility and death. Inhibiting the NAD salvage pathway in schistosome-infected mice significantly decreased NAD levels in adult parasites, which correlated with reduced egg production, fewer liver granulomas and parasite death. Thus, schistosomes, unlike their mammalian hosts, appear limited to one metabolic pathway to maintain NAD-dependent metabolic processes.
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| Minazzato, G., Gasparrini, M., Amici, A., Cianci, M., Mazzola, F., Orsomando, G., Sorci, L., & Raffaelli, N. (2020). Functional Characterization of COG1713 (YqeK) as a Novel Diadenosine Tetraphosphate Hydrolase Family. J Bacteriol., 202 (April), 2020, e00053-20. |
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Abstract:
Diadenosine tetraphosphate (Ap4A) is a dinucleotide found in both prokaryotes and eukaryotes. In bacteria, its cellular levels increase following exposure to various stress signals and stimuli, and its accumulation is generally correlated with increased sensitivity to a stressor(s), decreased pathogenicity, and enhanced antibiotic susceptibility. Ap4A is produced as a by-product of tRNA aminoacylation, and is cleaved to ADP molecules by hydrolases of the ApaH and Nudix families and/or by specific phosphorylases. Here, considering evidence that the recombinant protein YqeK from Staphylococcus aureus copurified with ADP, and aided by thermal shift and kinetic analyses, we identified the YqeK family of proteins (COG1713) as an unprecedented class of symmetrically cleaving Ap4A hydrolases. We validated the functional assignment by confirming the ability of YqeK to affect in vivo levels of Ap4A in B. subtilis YqeK shows a catalytic efficiency toward Ap4A similar to that of the symmetrically cleaving Ap4A hydrolases of the known ApaH family, although it displays a distinct fold that is typical of proteins of the HD domain superfamily harboring a diiron cluster. Analysis of the available 3D structures of three members of the YqeK family provided hints to the mode of substrate binding. Phylogenetic analysis revealed the occurrence of YqeK proteins in a consistent group of Gram-positive bacteria that lack ApaH enzymes. Comparative genomics highlighted that yqeK and apaH genes share a similar genomic context, where they are frequently found in operons involved in integrated responses to stress signals. By identifying the player contributing to Ap4A homeostasis in these bacteria, we disclose a novel target to develop innovative antibacterial strategies.
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| Mensà E, Guescini M, Giuliani A, Bacalini MG, Ramini D, Corleone G, Ferracin M, Fulgenzi G, Graciotti L, Prattichizzo F, Sorci L, Battistelli M, Monsurrò V, Bonfigli AR, Cardelli M, Recchioni R, Marcheselli F, Latini S, Maggio S, Fanelli M, Amatori S, Storci G, Ceriello A, Stocchi V, De Luca M, Magnani L, Rippo MR, Procopio AD, Sala C, Budimir I, Bassi C, Negrini M, Garagnani P, Franceschi C, Sabbatinelli J, Bonafè M, Olivieri F. Small extracellular vesicles deliver miR-21 and miR-217 as pro-senescence effectors to endothelial cells. J Extracell Vesicles, 9 (February), 2020, 1725285. |
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Abstract:
The role of epigenetics in endothelial cell senescence is a cutting-edge topic in ageing research. However, little is known of the relative contribution to pro-senescence signal propagation provided by microRNAs shuttled by extracellular vesicles (EVs) released from senescent cells. Analysis of microRNA and DNA methylation profiles in non-senescent (control) and senescent (SEN) human umbilical vein endothelial cells (HUVECs), and microRNA profiling of their cognate small EVs (sEVs) and large EVs demonstrated that SEN cells released a significantly greater sEV number than control cells. sEVs were enriched in miR-21-5p and miR-217, which target DNMT1 and SIRT1. Treatment of control cells with SEN sEVs induced a miR-21/miR-217-related impairment of DNMT1-SIRT1 expression, the reduction of proliferation markers, the acquisition of a senescent phenotype and a partial demethylation of the locus encoding for miR-21. MicroRNA profiling of sEVs from plasma of healthy subjects aged 40-100 years showed an inverse U-shaped age-related trend for miR-21-5p, consistent with senescence-associated biomarker profiles. Our findings suggest that miR-21-5p/miR-217 carried by SEN sEVs spread pro-senescence signals, affecting DNA methylation and cell replication.
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| Vernon Tebong Mbah, Vincent Pertici, Céline Lacroix, Bernard Verrier, Pierluigi Stipa, Didier Gigmes, Thomas Trimaille, “A Sacrificial PLA Block Mediated Route to Injectable and Degradable PNIPAAm-Based Hydrogels”, Polymers 2020, 12, 925. |
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Abstract:
Thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm)-based injectable hydrogels represent highly attractive materials in tissue engineering and drug/vaccine delivery but face the problem of long-term bioaccumulation due to non-degradability. In this context, we developed an amphiphilic poly(D,L-lactide)-b-poly(NIPAAm-co-polyethylene glycol methacrylate) (PLA-b-P(NIPAAm-co-PEGMA)) copolymer architecture, through a combination of ring-opening and nitroxide-mediated polymerizations, undergoing gelation in aqueous solution near 30 °C. Complete hydrogel mass loss was observed under physiological conditions after few days upon PLA hydrolysis. This was due to the inability of the resulting P(NIPAAm-co-PEGMA) segment, that contains sufficiently high PEG content, to gel. The copolymer was shown to be non-toxic on dendritic cells. These results thus provide a new way to engineer safe PNIPAAm-based injectable hydrogels with PNIPAAm-reduced content and a degradable feature.
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| Marco D’Orazio, Pierluigi Stipa, Simona Sabbatini, Gianluca Maracchini, “Experimental investigation on the durability of a novel lightweight prefabricated reinforced-EPS based construction system”, Construction and Building Materials 2020, 252, 119134. |
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Abstract:
This paper investigates the durability of a low-cost construction system named HOMEDONE developed to realize affordable and also temporary housing solutions. The system is based on the assembly of 3Dreinforced EPS panels externally topped off with a multi-layer rendering system. Similar technologies showed durability issues, especially in hot climates, due to the thermal and hygrometric stresses of the thin finishing layers when coupled to thick EPS panels and exposed to extreme events. For this reason, in this work freeze–thaw and wet/drying-UV aging tests on HOMEDONE panels with different finishing systems have been carried out, monitoring macroscopic, microscopic (ATR-FT-IR analysis) and bond strength variations due to aging. Results have pointed out good mechanical properties of the system and only small color variations of the finishing layer due to UV cycles. Then, HOMEDONE can be considered as a durable option for affordable and temporary housing solutions.
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| Cristina Minnelli, Roberta Galeazzi, Emiliano Laudadio, Adolfo Amici, Dario Rusciano, Tatiana Armeni, Mattia Cantarini, Pierluigi Stipa, Giovanna Mobbili, “Monoalkylated Epigallocatechin-3-gallate (C18-EGCG) as Novel Lipophilic EGCG Derivative: Characterization and Antioxidant Evaluation”, Antioxidants 2020, 9, 208. |
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Abstract:
Epigallocatechin-3-gallate (EGCG) has the highest antioxidant activity compared to the others catechins of green tea. However, the beneficial effects are mainly limited by its poor membrane permeability. A derivatization strategy to increase the EGCG interaction with lipid membranes is considered as one feasible approach to expand its application in lipophilic media, in particular the cellular absorption. At this purpose the hydrophilic EGCG was modified by inserting an aliphatic C18 chain linked to the gallate ring by an ethereal bond, the structure determined by NMR (Nuclear Magnetic Resonance) and confirmed by Density Functional Theory (DFT) calculations. The in vitro antioxidant activity of the mono-alkylated EGCG (C18-EGCG) was studied by the DPPH and Thiobarbituric Acid Reactive Substances (TBARS) assays, and its ability to protect cells towards oxidative stress was evaluated in Adult Retinal Pigmented Epithelium (ARPE-19) cells. Molecular Dynamics (MD) simulation and liposomal/buer partition were used to study the interaction of the modified and unmodified antioxidants with a cell membrane model: the combined experimental-in silico approach shed light on the higher a
nity of C18-EGCG toward lipid bilayer. Although the DPPH assay stated that the functionalization decreases the EGCG activity against free radicals, from cellular experiments it resulted that the lipid moiety increases the antioxidant protection of the new lipophilic derivative. |
| Valigi, D.; Fronzi, D.; Cambi, C.; Beddini, G.; Cardellini, C.; Checcucci, R.; Mastrorillo, L.; Mirabella, F.; Tazioli, A., “Earthquake-Induced Spring Discharge Modifications: The Pescara di Arquata Spring Reaction to the August–October 2016 Central Italy Earthquakes.”, Water, 2020, 12, 767 |
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Abstract:
Co-seismic changes in groundwater regime are often observed after moderate to strong earthquakes. The 24 August 2016 Mw 6.0 extensional Amatrice earthquake, which was the first event of a long-lasting seismic sequence, including the 30 October 2016 Mw6.5 Norcia event, triggered a significant discharge alteration to the Pescara di Arquata spring, located in the Umbria-Marche Apennines (Northern Apennines, Central Italy) and exploited for drinking purposes. During the first five months after the first mainshock, an extra flow of about 30% was recorded, while both water chemistry and temperature did not show significant changes. Thereafter, the spring discharge decreased significantly, and at the end of 2019 it was still lower than normal. The Standardized Precipitation Index (SPI) indicates that these low mean monthly discharge values are not related to particularly dry conditions. The increase in post-seismic depletion coefficients indicates that the aquifer empties faster than it did during the inter-seismic period. The observed transient increase and subsequent decrease of discharge are consistent with a transient, earthquake-related increase in hydraulic conductivity.
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| G. Busico, N. Colombani, D. Fronzi, D. Pellegrini, A. Tazioli, M. Mastrocicco, “Evaluating SWAT model performance, considering different soils data input, to quantify actual and future runoff susceptibility in a highly urbanized basin”, J. Environ. Manageme. 266 (July), 2020, 110625 |
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Abstract:
The Soil and Water Assessment Tool (SWAT) is a physical model designed to predict the hydrological processes that could characterize natural and anthropized watersheds. The model can be forced using input data of climate prediction models, soil characteristics and land use scenarios to forecast their effect on hydrological processes. In this study, the SWAT model has been applied in the Aspio basin, a small watershed, highly anthropized and characterized by a short runoff generation. Three simulations setup, named SL1, SL2 and SL3, were investigated using different soil resolution to identify the best model performance. An increase of space requirement and calibration time has been registered in conjunction with the increasing soil resolution. Among all simulations, SL1 has been chosen as the best one in describing watershed streamflow, despite it was characterized by the lower soil resolution. A map of susceptibility to runoff for the entire basin was so created reclassifying the runoff amount of four years in five classes of susceptibility, from very low to very high. Eleven sub-basins, coinciding with the main urban settlements, were identified as highly susceptible to runoff generation. Considering future climate predictions, a slight increase of runoff has been forecasted during summer and autumn. The map of susceptibility successfully identified as highly prone to runoff those sub-basins where extreme flood events were yet recorded in the past, remarking the reliability of the proposed assessment and suggesting that this methodology could represent a useful tool in flood managing plan.
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| G. Busico, N. Kazakis, N. Colombani, K. Khosravi K. Voudouris, M. Mastrocicco, “The importance of incorporating denitrification in the assessment of groundwater vulnerability”, Appl. Sci. 10(7) (April), 2020, 2328 |
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Abstract:
Human activities are deeply connected with groundwater reservoirs, so protecting them from pollution has become a priority in many regions of the world. Nitrate is considered the main groundwater pollutant since it is directly linked to many human activities. Agricultural activities and domestic wastewater have been identified as the main sources of nitrate in groundwater. Nevertheless, there are some natural processes that can mitigate nitrate pollution. Together with dilution processes, the degradation of nitrate through denitrification has been acknowledge as a process that can potentially reduce nitrogen loads, in both deep and shallow aquifers. Usually these processes were not properly quantified in vulnerability assessment methods, until the introduction of LOS indices. In this study, the application of the LOS indices on 4 agricultural areas is discussed, highlighting how the LOS indices can identify portions of the landscape with higher potential denitrification and how they directly enhance the groundwater vulnerability assessment. Previous studies have shown that LOS indices are a valuable tool for proper vulnerability assessment to nitrate, however they need to be coupled with other parameters that also describe nitrate behavior in groundwater. The SINTACS-SVN and DRASTIC-PA methods that include the LOS indices, were applied for the first time in the Epanomi coastal area to evaluate the reliably of the assessment and, despite the different classes range and the weights applied, similar groundwater vulnerability assessment maps were obtained. The nitrate vulnerability maps were comparable with the observed nitrate concentrations and were found to be highly comparable with original LOS maps. Nevertheless, it should be kept in mind that vulnerability methods are only screening tools and groundwater quality observations are pivotal information for environmental management.
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| G. Busico, N. Kazakis, E. Cuoco, N. Colombani, D. Tedesco, K. Voudouris, M. Mastrocicco, “A novel hybrid method of specific vulnerability to anthropogenic pollution using multivariate statistical and regression analyses”, Water Res. 171 (March), 2020, 115386 |
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Abstract:
Groundwater resources are the main supply of freshwater for human activities. However, in the last fifty years aquifers have become more susceptible to chemical pollution due to human activities. The concept of groundwater vulnerability constitutes a worldwide accepted tool for water protection and planning. However, the existing methods and modified versions do not account for all the hydrogeochemical processes that drive anthropogenic pollution. The hydrogeochemical processes occurring within an aquifer can be determined using multivariate statistical analysis. In this study a specific vulnerability method named SVAP (Specific Vulnerability to Anthropogenic Pollution) is proposed. The index is based on seven quantitative parameters: depth to groundwater, recharge, nitrate losses, hydraulic resistance of the vadose zone, aquifer thickness, hydraulic conductivity of the aquifer, and slope. Weights of anthropogenic factors were determined by factor analysis and used to validate the SVAP methodology. The parameters’ classification was selected according to the highest Pearson's correlation coefficient with factor weights and then grouped via a linear combination. The new index was applied in two watersheds: the Florina basin (Greece) and the Garigliano River basin (Italy), both of which possess complex hydrogeochemical regimes. The main hydrogeochemical processes acting in the study areas were identified via factor analysis, which revealed that the anthropogenic pollution in both sites was due mainly to chemical fertilizers and manure. Verification of the SVAP method produced correlation coefficients with nitrate concentrations of 0.75 and 0.62 in Florina and Garigliano, respectively. The proposed SVAP method is more reliable and flexible than standard vulnerability assessment methods and can be easily adapted for complex aquifers.
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| A. Belli, A. Mobili, T. Bellezze, F. Tittarelli “Commercial and recycled carbon/steel fibers for fiber-reinforced cement mortars with high electrical conductivity”, Cement and Concrete Composites 109 (2020) 103569 |
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Abstract:
The paper aims to provide a comprehensive study on the compositional optimization of high-conductive multifunctional fiber-reinforced cement mortars (FRCMs). Therefore, the effects of three different fiber types: virgin carbon fibers (VCFs), recycled carbon fibers (RCFs), and brass-plated steel fibers (BSFs), added at a broad range of concentrations, as 0.05%, 0.1%, 0.2%, 0.4%, 0.8%, 1.2%, and 1.6% by volume, on the mechanical, electrical and durability properties of FRCMs have been compared. The results showed that RCFs increase the flexural and tensile splitting strength up to 100%, whereas BSFs improve the compressive strength by 38%. Moreover, the fibers decrease both the capillary water absorption and the drying shrinkage by 39%. Electrical conductivity tests show that RCFs decrease the electrical resistivity of mortars up to one order of magnitude, in addition to a percolation threshold between 0.1 and 0.2 vol%.
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| J. Malaiskiene, M. Vaiciene, C. Giosuè, F. Tittarelli “The impact of bitumen roofing production waste (BTw) on cement mortar properties”, Construction and Building Materials 234 (2020) 117350 |
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Abstract:
This paper is aimed to show the impact of bitumen roofing production waste (BTw) on the properties of cement mortars in terms of mineral composition, microstructure, setting rate, physical and mechanical properties and durability (water absorption, freeze-thaw resistance). To this aim, mortar specimens were manufactured by replacing 0%, 2%, 4%, and 6% of natural sand by weight with BTw. The main results show that BTw slightly accelerates cement hydration and 4% is the best content of BTw to be valorised in mortars. In this case, compressive strength, density and ultrasound pulse velocity are comparable to the control mortar (0% BTw content) but capillary water absorption decreases and flexural strength increases. Moreover, at this dosage, the forecasted freeze-thaw resistance of mortars increases considerably (~30%).
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| A. Mobili, A. Telesca, M. Marroccoli, F. Tittarelli “Calcium sulfoaluminate and alkali-activated fly ash cements as alternative to Portland cement: study on chemical, physical-mechanical, and durability properties of mortars with the same strength class”, Construction and Building Materials 246 (2020) 118436 |
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Abstract:
There is an increasing interest towards the development of alternative binders for the manufacture of sustainable mortars and concretes. Ordinary Portland cement (OPC) is the most commonly used material in construction, even if its production process is highly polluting. Both calcium sulfoaluminate (CSA) and alkali-activated cements (AAC) are potential alternative binders to be used in both structural (R3 class, with Rc 25 MPa) and non-structural applications (R1 and R2 classes, with Rc 10 MPa and Rc 15 MPa, respectively) according to UNI EN 1504-3. This paper reports the hydration mechanisms and the evolution of porosity of OPC-, CSA- and AAC-based binders. The properties of fresh and hardened mortars, belonging to the above-mentioned mechanical strength classes, were evaluated and compared with particular emphasis on durability properties in terms of capillary water absorption, drying shrinkage, and resistance to sulfate attack. The results show that CSA-based mortars exhibit the lowest drying shrinkage due to their highest elasticity modulus. AAC mortars are characterized by the highest water vapor permeability and the lowest capillary water absorption for the highest presence of large pores (>3000 nm).
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| M. Hegde, L. Yang, F. Vita, R. J. Fox, R. van de Watering, B. Norder, U. Lafont, O. Francescangeli, L. A. Madsen, S. J. Picken, E. T. Samulski, T. J. Dingemans, “Strong graphene oxide nanocomposites from aqueous hybrid liquid crystals”, Nature Commun., 11(1), 2020, 830. |
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Abstract:
Combining polymers with small amounts of stiff carbon-based nanofillers such as graphene or graphene oxide is expected to yield low-density nanocomposites with exceptional mechanical properties. However, such nanocomposites have remained elusive because of incompatibilities between fillers and polymers that are further compounded by processing difficulties. Here we report a water-based process to obtain highly reinforced nanocomposite films by simple mixing of two liquid crystalline solutions: a colloidal nematic phase comprised of graphene oxide platelets and a nematic phase formed by a rod-like high-performance aramid. Upon drying the resulting hybrid biaxial nematic phase, we obtain robust, structural nanocomposites reinforced with graphene oxide.
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| C. Truzzi, E. Giorgini, A. Annibaldi, M. Antonucci, S.Illuminati, G. Scarponi, P. Riolo, N. Isidoro, C. Conti, M. Zarantoniello, R. Cipriani, I. Olivotto, “Fatty acids profile of black soldier fly (Hermetia illucens): influence of feeding substrate based on coffee-waste silverskin enriched with microalgae” – Animal Feed Science and Technology 259 (2020) 114309. DOI: 10.1016/j.anifeedsci.2019.114309 |
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Abstract:
The aim of this work was to find alternative low-cost and environmentally friendly rearing substrates for the growth of Hermetia illucens (HI) (Diptera, Stratiomydae), used as feed. At this purpose, insect feeding substrates based on the re-use of coffee silverskin, the main waste product of the coffee-roasting industry, enriched with various percentages of microalgae (i.e., Schizochytrium sp. or Isochrysis sp.), were tested. The fatty acid profile, as well as the relative amount of lipids, proteins and carbohydrates (these latter calculated as ratio to the total biomass of the sample) of ingredients, insect feeding substrates and HI prepupae, were determined for the first-time coupling Gas Chromatography-Mass Spectrometry and Fourier Transform Infrared Spectroscopy. A multivariate statistical analysis (Principal Component Analysis) was performed to better read into results. In general, the inclusion of microalgae caused in both feeding substrates and in HI prepupae an increase in the relative amount of lipids and proteins, improving their nutritional value. Higher amounts of unsaturated fatty acids, particularly of omega-3, and good nutritional indices were detected in HI prepupae reared on substrates enriched with 10%, 20% or 25% of Schizochytrium sp. with respect to HI prepupae fed with coffee silverskin enriched with Isochrysis sp., suggesting them as new nutraceutical ingredients for future functional feed and food. In addition, the substrate enriched with a 10% inclusion level of Schizochytrium sp. has to be considered the most convenient one since a greater inclusion of microalgae did not promote additional benefits in terms of nutritional value of HI prepupae.
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