Consumo energetico nel processo conciario: analisi delle fasi di lavorazione e possibilita di economie

Questo studio si propone di valutare i consumi energetici di una conceria campione, al fine di investigare ed individuare alternative più efficienti o modifiche degli impianti. La prima fase dello studio si è indirizzata sulla quantificazione delle energie consumate nel ciclo conciario per tre differenti tipologie di prodotto, operando fase per fase, dal ricevimento delle pelli salate fino alla vendita del prodotto finito. Per ogni lavorazione si sono così ottenuti i valori di energia termica ed elettrica consumati per ogni unità di prodotto trattata. Questo ha reso possibile un confronto tra lavorazioni in modo da individuare le fasi con i più alti consumi, sia in termini puramente energetici che economici. La seconda parte si è concentrata sulle fasi ad elevato fabbisogno energetico con l’obiettivo di proporre modifiche e migliorie per la riduzione delle richieste di energia, anche alla luce delle nuove tecnologie disponibili sul mercato. Si sono quindi rivalutati i consumi energetici del processo modificato in modo da quantificare, in termini energetici ed economici, i risparmi prodotti dagli interventi migliorativi

Antioxidant Efficiency of Platynereis spp. (Annelida, Nereididae) under Different pH Conditions at a Vent's System

Marine organisms are exposed to a pH decrease and to alteration of carbonate chemistry due to ocean acidification (OA) that can represent a source of oxidative stress which can significantly affect their antioxidant defence systems efficiency. The polychaetes Platynereis dumerilii and P. massiliensis (Nereididae) are key species of the benthic community to investigate the effect of OA due to their physiological and ecological characteristics that enable them to persist even in naturally acidified CO2 vent systems. Previous studies have documented the ability of these species to adapt to OA after short- and long-term translocation experiments, but no one has ever evaluated the basal antioxidant system efficiency comparing populations permanently living in habitat characterized by different pH conditions (acidified vs. control). Here, individuals of both Platynereis species, sampled from a natural CO2 vent system and from a nonventing "control" site in three different periods (April 2016, October 2016, and February 2017), were compared highlighting signals which suggested the ability of both species to acclimatize to high pCO2–low pH with slight seasonal variations of their antioxidant efficiency and the absence of disturbances of the oxidative status of Platynereis spp. tissues

Neustonic microplastics in the Southern Adriatic Sea. Preliminary results.

Neustonic micro-plastic abundance and polymeric composition were determined after a cruise conducted in the Southern Adriatic Sea between May 9th and 17th 2013. Plankton samples were collected using a Neuston net (200 µm mesh size) which sampled the first 50 cm of the sea surface at a speed of ~2 kts for 5-6 minutes. Samples were then stored in ethanol 70% and in the laboratory micro-plastics were hand-picked using a dissecting stereomicroscope, counted, weighed and split into 7 different size classes. On a subset of collected particles (> 0.7mm) FT-IR analyses were performed to characterize the polymeric composition of the items. All 29 surface tows contained plastic particles of various typologies (e.g. filaments, fragments, thin plastic films), colours and sizes. A total of 5940 plastic particles were collected during the survey, the vast majority of which were hard plastic fragments (78.5%) or synthetic fibers and filaments (19.2%). Most particles were white (27.8%), transparent (22.5%) or black/grey (21.4%). 98.2% of all the particles were < 5 mm and plastic abundance markedly increased with decreasing size (i.e. 52.8% of all the particles were smaller than 0.5 mm), indicating very high fragmentation rates. Overall, an average concentration of 1.05 ± 1.13 particles/m2 and 442.88 ± 1145.96 g/km2 was observed throughout the study area, with micro-plastic densities ranging from 0.10 particles/m2 to a maximum of 4.86 particles/m2. FT-IR analyses indicated polyethylene as the predominant polymer (41%), followed by polyester and paint (12%), polypropylene (10%), polystyrene and polyimide (5%), polyammide (3%), paraffin (4%) and 1% bioplastic (i.e. polycaprolactone). In addition, 7% of the items were characterized as non-plastic materials (i.e. minerals, cellulose and cotton fabric), suggesting a potential bias when visually sorting for micro-plastics. On the whole, very high levels of plastic pollution have been found in our study area. Despite any clear geographical pattern in plastic distribution was identified, the conspicuous spatial heterogeneity in plastic abundances and polymeric compositions seem to confirm the existence of multiple pollution sources insisting on the Adriatic Sea

Echinoderm larvae as bioindicators for the assessment of marine pollution: Sea urchin and sea cucumber responsiveness and future perspectives

Echinoderms play a crucial role in the functioning of marine ecosystems and due to their extensive distribution, rapid response, and the high sensitivity of their planktonic larvae to a large range of stressors, some species are widely used as biological indicators. In addition to sea urchins, sea cucumbers have recently been implemented in embryotoxicity bioassays showing high potential in ecotoxicological studies. However, the use of this species is still hindered by a lack of knowledge regarding their comparative responsiveness. The present study aimed to investigate the responsiveness of different echinoderm species to environmental pollution in order to develop their integration in batteries of ecotoxicological bioassays. To this end, the embryos of two sea urchins (Paracentrotus lividus and Arbacia lixula) and two sea cucumbers (Holothuria polii and Holothuria tubulosa) were incubated with inorganic and organic toxicants (cadmium, copper, mercury, lead, sodium dodecyl sulphate and 4-n-Nonhyphenol) and elutriates from contaminated marine sediments, chosen as a case study model. The results obtained, expressed through the percentage of abnormal embryos and Integrative Toxicity Indices (ITI), indicated species-specific sensitivities to pollutants, with comparable and correlated responsiveness between sea urchins and sea cucumbers. More specifically, sea cucumber larvae exposed to elutriates appear to be more sensitive than sea urchins, especially when incubated with samples containing trace metals, PCB and TBT. These results indicate that toxic responses in embryos exposed to environmental matrices are probably modulated by interactions between different variables, including additive, synergistic and antagonistic effects. These findings suggest that performing a larval test using different echinoderm classes can integrate the interactive effects of bioavailable fraction of contaminants on various levels, providing sensitive, representative and all year-round batteries of bioassays to apply in ecotoxicological studies

Oxidative responsiveness to multiple stressors in the key Antarctic species, Adamussium colbecki: interactions between temperature, acidification and cadmium exposure.

Abstract: High-latitude marine ecosystems are ranked to be among the most sensitive regions to climate change since highly stenothermal and specially adapted organisms might be seriously affected by global warming and ocean acidification. The present investigation was aimed to provide new insights on the sensitivity to such environmental stressors in the key Antarctic species, Adamussium colbecki, focussing also on their synergistic effects with cadmium exposure, naturally abundant in this area for upwelling phenomena. Scallops were exposed for 2 weeks to various combinations of Cd (0 and 40 μgL-1), pH (8.05 and 7.60) and temperature (-1 and +1°C). Beside Cd bioaccumulation, a wide panel of early warning biomarkers were analysed in digestive glands and gills including levels of metallothioneins, individual antioxidants and total oxyradical scavenging capacity, onset of oxidative cell damage like lipid peroxidation, lysosomal stability, DNA integrity and peroxisomal proliferation. Results indicated reciprocal interactions between multiple stressors and their elaboration by a quantitative hazard model based on the relevance and magnitude of effects, highlighted a different sensitivity of analysed tissues. Due to cellular adaptations to high basal Cd content, digestive gland appeared more tolerant toward other prooxidant stressors, but sensitive to variations of the metal. On the other hand, gills were more affected by various combinations of stressors occurring at higher temperatur

Cellular adaptations of the scleractinian coral Madracis pharensis to chronic oil pollution in a Mediterranean shipwreck

Chemical pollution in marine ecosystems is a factor of stress interacting in multiple and complex ways with other major causes of deterioration, such as warming seas due to climate change. Here we surveyed epibenthic communities from a shipwreck in the Levantine Basin for temporal and spatial changes in the community in relation to chronic oil pollution, comparing results collected from an area of the wreck characterized by chronic oil leakage with another area not affected by oil. Polycyclic aromatic hydrocarbons (PAHs) bioaccumulation analyses were integrated with characterization of the efficiency of xenobiotics biotransformation processes and antioxidant network of the scleractinian coral Madracis pharensis, chosen as bioindicator species. Results highlighted the two areas hosting different epibenthic communities over a period of 11 years. Significant changes in the percentage cover of M. pharensis could be the result of recent mass mortality associated to Marine Heat Waves. Biological investigation conducted in M. pharensis tissues revealed an increased content of PAHs in specimens collected from the oil-impacted area, coupled with an increased capability of oxyradicals scavenging capacity and a lower functionality of phase II biotransformation mechanisms associated to glutathione S-transferase. Overall, the results suggest that M. pharensis has the capability to develop cellular and physiological adaptations to chemical-mediated stress, with yet unknown possible energy trade-offs to sustain stress response

Platelet-Activating Factor and Kinin-Dependent Vascular Leakage as a Novel Functional Activity of the Soluble Terminal Complement Complex

AbstractThe infrequent occurrence of septic shock in patients with inherited deficiencies of the terminal complement components experiencing meningococcal disease led us to suspect that the terminal complement complex is involved in vascular leakage. To this end, the permeabilizing effect of the cytolytically inactive soluble terminal complement complex (SC5b-9) was tested in a Transwell system measuring the amount of fluorescein-labeled BSA (FITC-BSA) leaked through a monolayer of endothelial cells. The complex caused increased permeability to FITC-BSA after 15 min as opposed to the prompt response to bradykinin (BK). The effect of SC5b-9 was partially reduced by HOE-140 or CV-3988, two selective antagonists of BK B2 and platelet-activating factor receptors, respectively, and was completely neutralized by the mixture of the two antagonists. Also, DX-88, a specific inhibitor of kallikrein, partially inhibited the activity of SC5b-9. The permeabilizing factor(s) released after 30 min of incubation of endothelial cells with SC5b-9 caused a prompt leakage of albumin like BK. Intravital microscopy confirmed both the extravasation of circulating FITC-BSA across mesenteric microvessels 15 min after topical application of SC5b-9 and the complete neutralization by the mixture of HOE-140 and CV-3988. SC5b-9 induced opening of interendothelial junctions in mesenteric endothelium documented by transmission electron microscopy

Phantom without phantom or how the PT symmetry saves us from the Big Rip

We consider the PT symmetric flat Friedmann model of two scalar fields with positive kinetic terms. While the potential of one ("normal") field is taken real, that of the other field is complex. We study a complex classical solution of the system of the two Klein-Gordon equations together with the Friedmann equation. The solution for the normal field is real while the solution for the second field is purely imaginary, realizing classically the "phantom" behavior. The energy density and pressure are real and the corresponding geometry is well-defined. The Lagrangian for the linear perturbations has the correct potential signs for both the fields, so that the problem of stability does not arise. The background dynamics is determined by an effective action including two real fields one normal and one "phantom". Remarkably, the phantom phase in the cosmological evolution is transient and the Big Rip never occurs. Our model is contrasted to well-known quintom models, which also include one normal and one phantom fields.Comment: revised and enlarged version, to be published in Int. J. Mod. Phys. D, the title is change

The application of the Weight-Of-Evidence approach for an integrated ecological risk assessment of marine protected sites

The effective management of marine ecosystems in the face of growing anthropogenic pressures requires the integration of data from different ecological components. Holistic approaches to evaluate the ecological status of marine ecosystems are still scarce, likely due to the challenge of integrating the complex information from a variety of indicators. In this study, we provided an application of a quantitative Weight-Of-Evidence (WOE) model based on the Sediqualsoft ® software, combining environmental and biological data to assess ecological risk in soft-bottom habitats within Natura sites 2000 in the Northern Adriatic Sea (Mediterranean Sea). Here, the WOE approach combined three lines of evidence (LOE): chemical characterization (LOE1), ecotoxicological properties (LOE4), and benthic community status (LOE5). A separate hazard quotient was derived for each LOE prior to a weightedintegration into a synthetic WOE assessment. The chemical analysis of the sediments revealed concentrations of pollutants far lower the reference limits, except for As and Hg and for polycyclic aromatic hydrocarbons which determined a ‘Slight’ to ‘Severe’ chemical hazard in coastal sites. Ecotoxicological hazard was rated as ‘Absent ’ at all sampling stations, and the analysis of benthic communities indicated ‘undisturbed’ conditions for most sites. The WOE approach classified the overall ecological risk to be ‘Absent’ for offshore sites and ‘Slight’ in nearshore sites. Although results suggested a general low ecological risk, the potential for future risks is recognized, especially in coastal areas, due to well-known sediment pollution in the region. The application of the WOE approach may represent a valuable tool for managing marine protected sites, and to char acterize the overall ecological status of these areas and improve conservation strategies in highly anthropized environmental contexts