Spring and autumn spatial distribution of zooplankton carbon requirement across the Mediterranean Sea

Zooplankton represents a key contributor to the ocean biological pump through its consumption of sinking and suspended carbon. A specific and highly sensitive method to evaluate zooplankton carbon requirement from the sinking flux is through the estimation of the activity of the electron transport system. The present study was carried out from samplings in 2006, and it was focused on the spatial 200–0?m zooplankton carbon demand across 24 sampling stations, along the Mediterranean Sea, from the island of Crete to the Strait of Gibraltar. Its potential day/night variability was evaluated. The zooplankton composition, abundance and biomass were investigated. The carbon demand per unit zooplankton biomass indicates geographical and diel differences among the sampling stations. A higher mean carbon demand was seen for the western Mediterranean with respect to the eastern Mediterranean, which can be justified through the observed ratio of gelatinous:crustacean taxa and the water temperatures recorded. Higher carbon demand was measured in samples collected during the dark hours. The relation to the presence and abundance of actively migrating euphausiids and copepods was discussed. A comparison with data from another of our study carried out in the same study area but in another seasonal period was done.     

Novel two-step vapor-phase synthesis of UV–Vis light active Fe2O3/WO3 nanocomposites for phenol degradation

Supported Fe₂O₃/WO₃ nanocomposites were fabricated by an original vapor phase approach, involving the chemical vapor deposition (CVD) of Fe₂O₃ on Ti sheets and the subsequent radio frequency (RF)-sputtering of WO₃. Particular attention was dedicated to the control of the W/Fe ratio, in order to tailor the composition of the resulting materials. The target systems were analyzed by the joint use of complementary techniques, that is, X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDXS), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), and optical absorption spectroscopy. The results showed the uniform decoration of α-Fe₂O₃ (hematite) globular particles by tiny WO₃ aggregates, whose content could be controlled by modulations of the sole sputtering time. The photocatalytic degradation of phenol in the liquid phase was selected as a test reaction for a preliminary investigation of the system behavior in wastewater treatment applications. The system activity under both UV and Vis light illumination may open doors for further material optimization in view of real-world end-uses.

     

A field screening test for the assessment of concentrations and mobility of potentially toxic elements in soils: a case study on urban soils from Rome and Novi Sad

The increasing demand for environmental pollution control results in the development and use of new procedures for the determination of dangerous chemicals. Simple screening methods, which can be used directly in the field for a preliminary assessment of soil contamination, seem to be extremely advantageous. In our laboratory, we developed and optimized a rapid test for a preliminary evaluation of both the concentration and the mobility of some potentially toxic metals in soils. This screening test consists of a single extraction of the soil sample with a buffer solution, followed by the titration of the extracted solution with dithizone to determine the contents of bi-valent heavy metals (such as Pb, Cu, Zn, and Cd). This screening method was then directly applied in the field during the sampling campaign in the framework of an Italian–Serbian collaborative project, finalized in the study of metal availability in soils. The results obtained in the field with the rapid test were compared with those obtained in the laboratory following the conventional procedure commonly used to evaluate metal bioavailability (diethylenetriaminepentaacetic extraction). Moreover, selected samples were analyzed sequentially in the laboratory using the standardized BCR three-step sequential extraction procedure. The screening test gave results conceptually in good agreement with those obtained via the BCR procedure. These preliminary data show that the proposed screening test is a reliable method for the preliminary rapid evaluation of metal total concentrations and of potential metal mobility in soils, supporting sampling activities directly in the field.     

Poliovirus and Other Enteroviruses from Environmental Surveillance in Italy, 2009–2015

Within the initiatives for poliomyelitis eradication by WHO, Italy activated an environmental surveillance (ES) in 2005. ES complements clinical Acute Flaccid Paralysis (AFP) surveillance for possible polio cases, detects poliovirus circulation in environmental sewage, and is used to monitor transmission in communities. In addition to polioviruses, the analyses comprised: (i) the monitoring of the presence of non-polio enteroviruses in sewage samples and (ii) the temporal and geographical distribution of the detected viruses. From 2009 to 2015, 2880 sewage samples were collected from eight cities participating in the surveillance. Overall, 1479 samples resulted positive for enteroviruses. No wild-type polioviruses were found, although four Sabin-like polioviruses were detected. The low degree of mutation found in the genomes of these four isolates suggests that these viruses have had a limited circulation in the population. All non-polio enteroviruses belonged to species B and the most frequent serotype was CV-B5, followed by CV-B4, E-11, E-6, E-7, CV-B3, and CV-B2. Variations in the frequency of different serotypes were also observed in different seasons and/or Italian areas. Environmental surveillance in Italy, as part of the ‘WHO global polio eradication program’, is a powerful tool to augment the polio surveillance and to investigate the silent circulation or the re-emergence of enteroviruses in the population.