Persistent Organic Pollutants in a marine bivalve on the Marennes-Oléron Bay and the Gironde Estuary (French Atlantic coast) -Part 2: Potential biological effects

International audienceContaminant effects on defence responses of ecologically and economically important organisms, such as the Pacific oyster Crassostrea gigas, are likely to influence their ability to resist infectious diseases, particularly at the young stages. The aim of this study was to explore the potential relationships between organic contaminants accumulated in the soft tissues of juvenile oysters, defence responses and physiological condition. Oysters were transplanted during summer and winter periods in different sites in the Marennes-Oléron Bay, the first area of oyster production in France, and in the Gironde Estuary, the biggest estuary in Occidental Europe. Among the battery of biochemical and physiological biomarkers applied in the present work (superoxide dismutase -SOD-, catalase, glutathione peroxidase -GPx-, malondyaldehyde -MDA-, catecholase, laccase and lysozyme in gills, digestive gland, mantle and haemolymph, glycogen, proteins and lipids in the digestive gland and the condition index at the whole organism level), MDA and lysozyme in the digestive gland and SOD, GPx and laccase in plasma contibuted to significantly discriminate sites in which oysters bioaccumulated different levels of heavy polycyclic aromatic hydrocarbons (HPAHs), polychlorobiphenyls (PCBs), polybromodiphenylethers (PBDEs), dichlorodiphenyltrichloroethanes (DDTs) and lindane. These results strengthen the hypothesis that it is possible to differentiate sites depending on their contamination levels and biological effects by carrying out studies with transplanted juvenile oysters. In addition, correlations between antioxidant and immune defence responses and PAH and DDT body burdens in the first area of oyster production in France, the Marennes-Oléron Bay, and where massive oyster mortalities have been reported, suggest that the presence of organic chemical contaminants in the Marennes-Oléron Bay may influence defence responses in juveniles of C. gigas, and, therefore, could influence their ability to resist infectious diseases

Integrative biomarker assessment of the effects of chemically and mechanically dispersed crude oil in Pacific oysters, Crassostrea gigas

International audienceThe impact of dispersed crude oil and dispersant on adult Pacific oysters, Crassostrea gigas, was evaluated through an integrative biomarker approach including (1) biochemical (plasma catecholase- and laccase-type phenoloxidase and superoxide dismutase), (2) histological (digestive cell lysosomal responses, digestive gland histopathology) and (3) physiological (flesh condition index) endpoints in the haemolymph and digestive gland. Adult oysters were exposed to non-contaminated water (control), chemically-dispersed oil (Brut Arabian Light), mechanically-dispersed oil and dispersant (FINASOL®) alone for 2 days, and further depurated in noncontaminated water for 4 weeks. After exposure to chemically and mechanically dispersed oil oysters exhibited induction of plasma laccase-type phenoloxidase and superoxide dismutase activities, enlargement of digestive cell lysosomes, lipofuscin accumulation, reduced neutral lipid content and atrophy of digestive gland diverticula; more markedly on exposure to chemically dispersed oil. From the studied biomarkers, only lysosomal biomarkers were significantly affected after exposure to the dispersant alone. This included lysosomal enlargement, neutral lipid depletion and lipofuscin accumulation in the digestive gland epithelium. A recovery of plasma enzyme activities was observed after 4 weeks of depuration. The integrative biological response index indicated that chemically dispersed oil caused significantly higher stress to C. gigas than the mechanically-dispersed one or the dispersant alone; nevertheless, the response seems to be reversible after depuration

Propuesta metodológica para incorporar variables socioeconómicas, culturales e institucionales en la caracterización de humedales a partir del enfoque de sistemas socioecológicos.

Este producto es elaborado en el marco del convenio 005 (13-014) entre el Instituto Humboldt y el Fondo Adaptación, este documento se presenta un conjunto de variables que deben considerarse en la identificación y delimitación de estos sistemas, basados en un enfoque conceptual de sistemas socioecológicos y considerando de manera explícita aspectos socioeconómicos, culturales e institucionales.Bogotá, ColombiaSubdirección de Servicios Científicos y Proyectos Especiale

Molecular confirmation of three xylotrophic bivalve species (Family Teredinidae) from Cartagena Bay and Barbacoas Bay, Caribbean Sea, Colombia

A pesar de la existencia de un extenso hábitat de manglares en Colombia, solo unos pocos estudios han descrito la diversidad de bivalvos teredinidos xilótrofos (conocidos como “broma”) en el país. El presente estudio investigó la presencia de bivalvos teredinidos en las bahías de Cartagena y Barbacoas. En un estudio de campo llevado a cabo en marzo de 2013, diez individuos de dos géneros de Teredinidae, correspondientes morfológicamente a Neoteredo reynei y Bankia spp., fueron encontrados en las raíces sumergidas de mangle rojo (Rhizophora mangle). Identificaciones morfológicas iniciales se complementaron con identificación molecular. Para esto, dos fragmentos de genes fueron secuenciados: 588 pares de bases (pb) del gen mitocondrial citocromo oxidasa subunidad 1 (CO1) y 305 pb del gen nuclear de la subunidad ribosómica pequeña (18S). Búsquedas de alineación básica (BLAST) y árboles filogenéticos utilizando secuencias de CO1 y 18S de otras especies de Teredinidae públicamente disponibles y no publicadas confirmaron la identidad de Neoteredo reynei en la bahía de Barbacoas. En contraste, las secuencias obtenidas para Bankia, indicaron la presencia de dos especies distintas en la bahía de Cartagena. La confirmación de al menos tres especies de Teredinidae en las bahías de Cartagena y Barbacoas sugiere la presencia de especies adicionales y justifica un mayor esfuerzo de muestreo para este grupo de descomponedores de madera tan importante ecológica y económicamente

The discursive axes of inclusive education to mitigate school discrimination: a documentary review

La inclusión educativa es una tarea que la escuela ha asumido de manera tardía, a partir de las diferentes deliberaciones que los países miembros de la Organización de Naciones Unidas ONU han realizado, buscando, en cada una, acabar con las diferentes formas de discriminación y exclusión que han marcado la historia de la humanidad. La escuela colombiana, concretamente, ha hecho esfuerzos normativos en la materia, pero, no resulta claro, hasta qué punto, los niños, niñas y adolescentes que requieren, por sus condiciones o características, formas específicas de tratamiento escolar, que, al parecer, no se implementan adecuadamente en todos los casos. Verificar que la inclusión sea un hecho cotidiano en la escuela es tarea de todos los actores escolares: padres de familia, docentes, directivos y las instituciones encargadas de regular la educación. Por tanto, el objetivo es pensar, reflexionar y examinar la efectividad de los ejes discursivos de gestión escolar, inclusión e interculturalidad en la mitigación de la discriminación a través de una revisión documental. En consecuencia, esta investigación identificó, clasificó y sistematizó documentos que se relacionarán directamente con el objeto de estudio haciendo uso de la literatura alojada en bases de datos tales como, Scielo, Scopus y Google Académico. Destacando que en dicha búsqueda se emplearon como criterios de exclusión artículos que fueran publicados antes de 2010, igualmente no se tomaron en cuenta aquellos estudios que no estuvieran relacionados con educación. Este ejercicio arrojó un total de 107 documentos entre artículos, libros, tesis y normativas. Finalmente, se escogen según las categorías de gestión escolar, inclusión e interculturalidad, 18 documentos, teniendo en cuenta su afinidad. Se concluye que debe existir coherencia entre la teoría y la práctica, además una acción decidida de la sociedad en contra de la discriminación. No obstante, aunque se han implementado políticas y programas en Colombia al respecto, aún existen grandes desafíos, como: la generación de recursos, la formación de los docentes en atención a la diversidad e implementar políticas, culturas y prácticas inclusivas en las instituciones educativas.Secretaria de Educación de BogotáMagíster en Educación Inclusiva e InterculturalMaestríaEducational inclusion is a task that the school has assumed late, based on the different deliberations that the member countries of the UN have carried out, seeking, in each one, to end the different forms of discrimination and exclusion that have marked the history of humanity. The Colombian school, specifically, has made normative efforts in the matter, but it is not clear, to what extent, the children and adolescents who require, due to their conditions or characteristics, specific forms of school treatment, which, apparently, they are not properly implemented in all cases. Verifying that inclusion is a daily occurrence at school is the task of all school actors: parents, teachers, managers and the institutions in charge of regulating education. Therefore, the objective is to think, reflect and examine the effectiveness of the discursive axes of school management, inclusion and interculturality in the mitigation of discrimination through a documentary review. Consequently, this research identified, classified, and systematized documents that will be directly related to the object of study, making use of the literature housed in databases such as Scielo, Scopus, and Google Scholar. Noting that in said search, articles that were published before 2010 were used as exclusion criteria, likewise those studies that were not related to education were not taken into account. This exercise yielded a total of 107 documents including articles, books, theses and regulations. Finally, 18 documents are chosen according to the categories of school management, inclusion and interculturality, taking into account their affinity. It is concluded that there must be coherence between theory and practice, as well as a decided action by society against discrimination. However, although policies and programs have been implemented in Colombia in this regard, there are still great challenges, such as: generating resources, training teachers in attention to diversity and implementing inclusive policies, cultures and practices in educational institutions

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum