A novel ionic exchange membrane crystallizer to recover magnesium hydroxide from seawater and industrial brines

A novel technology, the ion exchange membrane crystallizer (CrIEM), that combines reactive and membrane crystallization, was investigated in order to recover high purity magnesium hydroxide from multi-component artificial and natural solutions. In particular, in a CrIEM reactor, the presence of an anion exchange membrane (AEM), which separates two-compartment containing a saline solution and an alkaline solution, allows the passage of hydroxyl ions from the alkaline to the saline solution compartment, where crystallization of magnesium hydroxide occurs, yet avoiding a direct mixing between the solutions feeding the reactor. This enables the use of low-cost reactants (e.g., Ca(OH)2) without the risk of co-precipitation of by-products and contamination of the final crystals. An experimental campaign was carried out treating two types of feed solution, namely: (1) a waste industrial brine from the Boles\u142aw \u15amia\u142y coal mine in \u141aziska G\uf3rne (Poland) and (2) Mediterranean seawater, collected from the North Sicilian coast (Italy). The CrIEM was tested in a feed and bleed modality in order to operate in a continuous mode. The Mg2+ concentration in the feed solutions ranges from 0.7 to 3.2 g/L. Magnesium recovery efficiencies from 89 up to 100% were reached, while magnesium hydroxide purity between 94% and 98.8% was obtained

Bio-plastic recognition by mussels hemocytes

The growing use of bio-polymers derivatives poses an increasingly pressing problem regarding their environmental sustainability. In particular, it should be still ascertained the claimed absence of direct and indirect influence on ecosystems and the health of living organisms, including humans. Our goal was about assessing the potential effects of poly-lactates and polyhydroxyalkanoates, the most widely used bio polymers classes with promising different applications for replacing conventional plastics on natural aquatic environments. We chose M. galloprovincialis as sentinel species since their extensive filter-feeding activity. When it is exposed to microparticles can bioaccumulate them in soft tissues and organs. In the immunobiological investigation, to highlight if bio-polymers can influence the marine ecosystems, in vitro exposure assays on bivalve mussel have been carried out, and their impacts have been explored, by evaluating the cellular response of hemocytes referred to their phagocytic and/or encapsulation activity. Preliminary evidences have shown that bioplastic particles behave in a very similar way to fossil plastic triggering the immuno-system and activating the elimination of non-self particles via cellular response. As future perspectives, although it is widely recognized that in vitro testing is an effective method for defining the effects of emerging pollutants, the in vitro test will be further deepened with in vivo experiments

Le fabuliste, le professeur de FLE et les méthodologies

Nous nous proposons d’examiner la place tenue par les Fables de La Fontaine dans les différentes méthodologies d’enseignement-apprentissage du FLE (français langue étrangère). Pour mener cette étude, nous avons examiné une sélection représentative de méthodes de FLE destinées à des publics d’enfants, d’adolescents et d\u27adultes, manuels généralistes de langue, mais aussi manuels plus spécifiques consacrés à la découverte de la littérature (type anthologies). Nous avons complété cette étude par celle du Français dans le monde, revue pédagogique à destination des enseignants de FLE. Les questions posées à partir du corpus retenu concernent la sélection des Fables présentées, leurs modalités de présence et d’exploitation. Nous avons choisi d’envisager la question d’un point de vue diachronique et de nous intéresser à la manière dont la place des Fables varie au gré des méthodologies. Pendant la période envisagée (des années 1950 à aujourd’hui), le texte littéraire a été tout d’abord « sacralisé », puis « désacralisé » (Gruca, 1993) ; depuis une quinzaine d’années, on observe un regain d’intérêt à son endroit, même si de nombreux freins subsistent. Notre étude montre que les Fables sont passées du statut de classique pour les apprenants de FLE à celui d’échantillon du patrimoine culturel français, et nous permet, chemin faisant, d’interroger la place de la littérature et la notion de patrimoine littéraire dans le domaine spécifique du FLE

Fish Welfare in Aquaculture: Physiological and Immunological Activities for Diets, Social and Spatial Stress on Mediterranean Aqua Cultured Species

Welfare assessment currently is less well-characterized for aquatic animals and the clas- sical methodologies used for terrestrial animals are not adequate to improve our knowledge about fish well-being. Among different approaches, the status of organism responses can be carried out using different physiological and biochemical tools. Here, we present the state of the art regarding fish welfare, methodologies, and experimental results with a particular focus on two important Mediterranean aquaculture species, Sparus aurata and Dicentrarchus labrax. We introduce an approach using physiological stress-indicators, growth performance and swimming activity to investigate the effects of the implantation of electronic tags to facilitate the application of telemetry for aquaculture purposes. The application of telemetry to research on aquatic organisms has expanded recently, and its utilization needs to be better understood. The mentioned approaches have been discussed for application in different aquaculture methodologies. Moreover, social stress and territoriality are relevant factors in the evaluation of gregarious species that may have consequences on the conditions of animals farmed in captivity. These aspects, that may impair the ability of fish to respond to various stimuli or negatively influence the flesh quality, here are analysed through behavioural observation, flanked by the physiological and immunological approach

A pilot-plant for the selective recovery of magnesium and calcium from waste brines

The problem of brines disposal has raised great interest towards new strategies for their valorisation through the recovery of minerals or energy. As an example, the spent brine from ion exchange resins regeneration is often discharged into rivers or lakes, thus impacting on the process sustainability. However, such brines can be effectively reconcentrated, after removal of bivalent cations, and reused for the resins regeneration. This work focuses on developing and testing a pilot plant for selective recovery of magnesium and calcium from spent brines exploiting a novel proprietary crystallization unit. This is part of a larger treatment chain for the complete regeneration of the brine, developed within the EU-funded ZERO BRINE project. The pilot crystallizer was tested with the retentate of the nanofiltration unit processing the spent brine from the industrial water production plant of Evides Industriewater B.V. (Rotterdam, The Netherlands). Magnesium and calcium hydroxide were selectively precipitated by adding alkaline solution in two consecutive steps and controlling reaction pH. Performance was assessed in terms of recovery efficiency and purity of produced crystals, observing in most investigated cases a recovery of about 100% and 97% and a purity above 90% and 96%, for magnesium and calcium hydroxide, respectively

The multiple potentialities of anthozoans: analyses and comparisons between animal models

Anthozoans are the richest class of species of the phylum Cnidaria. They are a candidate group for studying the evolution of mutualisms and immunity and despite their morphological simplicity exhibit a repertoire of immunological components with large genomes and gene families similar to those of the Bilateria. Like other invertebrates, anthozoans immunity is based on self/non-self recognition mechanisms and allorecognition responses, therefore, maintaining their integrity and responding actively to selection pressures. Highlight and investigate the link between innate immunity, homeostasis maintenance, inflammation, tissue remodelling and regeneration in Anthozoa could be useful to elucidate the adaptive capability features to different stress factors. We have carried out studies demonstrating that all these processes are highly conserved among the anthozoans species. We have compared the inflammatory responses and the morpho-functional aspects related to regeneration in different species of Mediterranean anthozoans using histological, cellular and molecular technical approaches on organisms, maintained in aquaria under environmental and pathogenic stressful conditions. This approach appears to be a useful tool from baseline studies in immunology and anthozoans result valid models able to respond to environmental stress conditions. Important results have been obtained with potential biotechnological transferability in pharmacology

Actinins as novel broad-spectrum AMP isolated from the tentacle of Anthozoan Actinia equina (Linnaeus, 1758)

Capturing activities and defense mechanisms of Cnidarian are strongly associated with toxins and peptide with antimicrobial properties. AMP are an important component of many organisms’ innate immune system with a good inhibitory or killing effect against invaders pathogens. We investigated the AMP activity of acid extracts obtained from tentacle and body of Actinia equina (Cnidaria, Anthozoa) against Gram positive (Micrococcus lysodeikticus) and Gram negative (Escherichia coli, Vibrio alginolyticus) bacteria. The peptide fractions showed interesting minimum inhibitory concentrations (MIC) values (concentrations up to 0.125 μg/ml) against tested pathogens. Tentacle acid extracts exhibiting a good antimicrobial activity, were further investigated, characterized and the peptides purified by reverse phase chromatography on solid phase Sep-Pak C8 column followed by several HPLC runs on C18 column. A broad-spectrum antibacterial peptides activity was detected in 40 % acetonitrile fractions. The Peptide 6.2 has a molecular weight of 2612.91 Da and is composed of 27 amino acids (Actinin A); while peptide 7.3 has a molecular weight of 4323.07 Da and is composed of 35 amino acids (Actinin B). The two peptides were completely sequenced and their aa sequence revealed similarity with the already described AMPs identified in amphibians and fish, with anti-Gram+ & Gram-, antifungal, candidacidal, anti- Methicillin-resistant Staphylococcus aureus (MRSA) activity Actinins A and B were chemically synthesized and tested in vitro against the above-mentioned bacterial pathogens. The analysis identified the peptide Actinin B which showed an interesting antibacterial and can be considered good candidates for new therapeutic applications

Contribuição da abordagem geocientífica no ensino fundamental : tempo geológico, origem do petróleo e mudanças ambientais

O presente artigo descreve uma experiência em sala de aula com alunos da 4ª série do ensino fundamental em escola pública em São Paulo, Brasil. Em 2007 foram desenvolvidas atividades do conteúdo programático de Ciências, segundo uma abordagem geológica. O objetivo inicial da professora era dar aos alunos referenciais importantes para explorarem e compreenderem os recursos naturais renováveis e não renováveis, usando como tema gerador o petróleo e as conseqüências ecológicas dos grandes derramamentos ou vazamentos do produto no mar. Baseando-se na metodologia dialética, a partir de argumentações e perguntas elaboradas, procurou-se estabelecer contextos, diferentes significados e representações do assunto, sendo a parceria entre professora e pesquisadora essencial para a superação da fragmentação do saber sobre a questão do conteúdo e sua relação com a didática

Cuantificación del contenido de nitratos, fluoruros, sulfatos, cloruros, carbonatos, hidrogenocarbonatos, sodio, potasio, sales rotales y dureza total en aguas de Santa Rosa (L.P.)

Between the months of August 1985 and May 1986, 83 samples of water from different section of Santa Rosa city were analyzed to know the contens of: de NO3-, F-, SO4 2-, Cl-, CO32-,HCO3-,  Na+, K+, total salt and D.T. in well water destined for human consumption. In the analyzed samples the following vas detected:- 43% of them surpases the acceptable value as regardes F-- The 8,5% of them contains an excess of NO3-- The 35% of them have a high content of SO42-- The 23% of them have surfaces the normal values of Cl-- Only 22% of them take tolerable contains of T.H., total salt and other studied ions.Entre los meses de agosto de 1985 y Mayo de 1986 se analizaron 83 muestras de agua de distintos sectores de la ciudad de Santa Rosa, para conocer los contenidos de NO3-, F-, SO4 2-,Cl-, CO32-,HCO3-,  Na+, K+, sales totales y D.T. en aguas de pozo destinadas a consumo humano. En las muestras analizadas se detectó lo siguiente:- el 43% de las mismas supera los valores aceptables respecto al F.- el 8,5% de las mismas tiene exceso de NO3-.- el 35% de las mismas posee un elevado conten1do de SO4-2- solamente el 22% de las muestras tiene valores tolerados de sales totales, D.T y las especies químicas analizadas