Effect of combined physico-chemical processes on the phytotoxicity of olive mill wastewaters

A pool of laboratory experiments is planned with the aim of evaluating the possibility to reduce the phytotoxicity of olive mill wastewater (OMW) with combined physico-chemical processes (centrifugation-ozonation, centrifugation-solar photolysis, centrifugation-solar modified photoFenton, centrifugation-solar modified photoFenton-ozonation). A moderate COD removal of an OMW is reached by using ozonation or solar modified photoFenton separately or solar modified photoFenton/O(3) combined process even for prolonged treatment times. The O(3)-treated OMWs are still toxic towards algal growth (Pseudokirchneriella subcapitata) and only for dilutions equal to or higher than 1:160 a stimulation of algal growth is observed. The sole ozonation does not reduce significantly the phytotoxicity of tested OMW measured through the GI calculation of Raphanus sativus L., Cucumis sativus L. and Lactuca sativa L. A marked reduction of OMW inhibition, higher than 50%, is evidenced for 1:8 dilution OMW samples ozonated for 2h. The long-term storage of OMW associated with solar irradiation without or with Fe(III) ions under continuous aeration is less efficient than ozonation, and the combined action of the two former treatments does not significantly contribute to enhance both COD removal and germination index. Better results are obtained on seed germination and root elongation of plantlets of the three selected species, which germinated on OMW-free solidified medium and were then transferred on a solidified culture medium containing O(3)-treated OMW diluted 1:2 and 1:4. The operating costs are estimated for the solar modified photoFenton-ozonation process.     

Design of a holonic remote monitoring and diagnosis system for fleet management

The main challenges in sensor network based monitoring systems are the control and management of complex modules and elements interacting among them and with the environment. This work presents and validates a design model for monitoring and diagnosis systems based on sensor networks exploiting potentialities of the holonic approach. The holonic structure is designed with the final goal to guarantee the performances and the functionalities required by the application scenario of road and work vehicles rental companies. Actually they are interacting and geographically distributed systems. The capabilities of cooperation among modules, hierarchical organization, modularity and reliability of holonic design are exploited. Diagnosis of monitored events is coded and validated through an ad hoc ontology. The design does not give assumption on the physical architecture of holons but only on their capacities/properties, therefore it can be reused in different physical and hardware resources. The case studies confirm the capability of our design to be quickly transferred to programmers and coded in firmware and software.     

Ambient temperature modelling with soft computing techniques

This paper proposes a hybrid approach based on soft computing techniques in order to estimate monthly and daily ambient temperature. Indeed, we combine the back-propagation (BP) algorithm and the simple Genetic Algorithm (GA) in order to effectively train artificial neural networks (ANN) in such a way that the BP algorithm initialises a few individuals of the GA’s population. Experiments concerned monthly temperature estimation of unknown places and daily temperature estimation for thermal load computation. Results have shown remarkable improvements in accuracy compared to traditional methods.     

Stable Non‐Covalent Large Area Patterning of Inert Teflon‐AF Surface: A New Approach to Multiscale Cell Guidance

Micro‐ and nano‐patterning of cell adhesion proteins is demonstrated to direct the growth of neural cells, viz. human neuroblastoma SHSY5Y, at precise positions on a strongly antifouling substrate of technolological interest. We adopt a soft‐lithographic approach with oxygen plasma modified PDMS stamps to pattern human laminin on Teflon‐AF films. These patterns are based on the interplay of capillary forces within the stamp and non‐covalent intermolecular and surface interactions. Remarkably, they remain stable for several days upon cell culture conditions. The fabrication of substrates with adjacent antifouling and adhesion‐promoting regions allows us to reach absolute spatial control in the positioning of neuroblastoma cells on the Teflon‐AF films. This patterning approach of a technologically‐relevant substrate can be of interest in tissue engineering and biosensing.     

Comparison of different soil organic matter fractionation methodologies: Evidences from ultrasensitive 14C measurements

Soils are studied with the aim to predict future climatic scenarios and find the best guidelines to manage terrestrial ecosystems for the mitigation of the atmospheric CO₂ rising. Carbon constituting soil organic matter (SOM) behaves as a cohort of different pools, characterized by a specific C turnover time. Both natural and anthropogenic occurring ¹⁴C reach the soil through plant littering, becoming a valid tool to trace SOM dynamics.In this study we present a series of Accelerator Mass Spectrometry (AMS) ¹⁴C measurements on SOM samples obtained by means of different laboratory protocols used for the isolation of soil pools from bulk soil (fractionation protocols). Radiocarbon signature of SOM fractions is used as a keyhole to look at the more effective fractionation procedure and comparison among measured ¹⁴C on SOM fractions revealed important indications for the proposal of a novel fractionation protocol. Our data put in evidence how particle size controls the recalcitrance of ancient SOM carbon pools.     

The oxidation mechanism of the antioxidant quercetin in nonaqueous media

The knowledge of the degradation pathways of natural dyes used in medieval textiles is necessary for the restoration of their original color. Quercetin, one of such colorants, reportedly yields the wide spectrum of oxidation products in different types of media. This study deals with electrochemical oxidation mechanism of quercetin in nonaqueous solution, which has not been yet attempted. The final oxidation product at the first oxidation wave was identified by HPLC-DAD and GC–MS techniques as 2-(3′,4′-dihydroxybenzoyl)-2,4,6-trihydroxybenzofuran-3(2H)-one. The apparent two-electron process at the potential of the first oxidation wave yields current–voltage shapes with one-electron characteristics. The in situ spectroelectrochemistry measurements proved the oxidation mechanism leading through a short-lived anion radical. Two possibilities of the oxidation mechanism are discussed: two one-electron transfers, which do not have identical but similar redox potentials, or the presence of a disproportionation chemical reaction following the first one electron transfer. The quinone formed in either case is stable only on the time scale of a fast spectroelectrochemistry and undergoes fast hydroxylation reaction, where 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxybenzofuran-3-one is formed. This compound is oxidized at the potential of the second oxidation wave of quercetin.     

Aluminium electroplated from ionic liquids as protective coating against steel corrosion

The protective action of thin layers of aluminium electroplated on a carbon steel (UNI Fe360B) has been studied. The coatings were obtained via electroreduction, at room temperature, from an ionic liquid constituted by 1-butyl-3-methyl-imidazolium heptachloroaluminate. Coatings of different thickness, ranging from 10 to 40 μm, were obtained. Their morphology and chemical composition were investigated using SEM microscopy coupled with EDX microanalysis and X-ray diffraction. Electrochemical tests (potentiodynamic polarization curves, open-circuit potential and electrochemical impedance spectroscopy) were performed in order to characterise the corrosion resistance of the coating in 3.5% NaCl aqueous solution. Visual investigation of the samples during long term of exposition to neutral salt spray gave an evaluation of their free corrosion properties. It was found that the aluminium layers deposited from ionic liquids significantly protect the substrate from the general corrosion and this action increases with the coating thickness.     

DNA damage, severe organ lesions and high muscle levels of As and Hg in two benthic fish species from a chemical warfare agent dumping site in the Mediterranean Sea

The aim of the present study was to evaluate the environmental threat to benthic species from chemical weapons dumped in the southern Adriatic Sea. An ecotoxicological approach using chemical analysis and biological responses was applied, in two sentinel species: the Blackbelly rosefish Helicolenus dactylopterus and European conger Conger conger. Specimen were collected in a stretch of sea, where had been dumped war materials and from a reference site free of ordnance. Residues of yperite, Hg and As were measured in fish fillets. Skin, liver, kidney and spleen were examined for histopathological and macroscopical lesions. Liver detoxifying capacities (EROD and UDPGT) and genotoxicity (comet assay) were also investigated. As and Hg levels were three-four times higher than those from the reference site in both species (p < 0.001). Both species captured in dumping site showed clear signs of chronic illness according to the health assessment index (HAI). Deep ulcers and nodules were observed on skin and external organs. Histological lesions such as periportal and bile duct fibrosis, pericholangitis, steatosis, granuloma and elevated splenic MMCs were detected in liver and spleen. Significantly higher EROD activities were also found in both species from dumping site (p < 0.01). Comet assay revealed genotoxicty in gills of C. conger from dumping site, indicating uptake of chemical warfare agents through fish gills. European conger was found to be a more sensitive bioindicator of this type of contamination than the Blackbelly rosefish.