1-(Benzoylamino)-3-methylimidazolium chlorochromate (BAMICC), a new selective and mild reagent for the oxidation of allylic and benzylic alcohols

A new mild chromium(VI) oxidizing reagent, the 1-(benzoylamino)-3-methylimidazolium chlorochromate (BAMICC) has been prepared as a stable yellow-orange solid which selectively oxidizes allylic and benzylic alcohols, including those bearing basic nitrogens, to carbonyl compounds.The authors are grateful for a grant (MAH) received from Ministerio de Educación y Ciencia and for financial support from Comisión lnterministerial de Ciencia y Tecnología (CICYT, project PB90-0284

Synthesis and structure of complexes of acyl N-aminides with zinc(II) salts

The structures of complexes obtained by reacting acyl N-aminides and ZnCl2 were ascertained by X-ray analysis and were show to incorporate one Zn atom and two molecules of the N-aminide in a distorted tetrahedral geometry. Bis-aminides act as bidentate ligands forming ZnLCl2 complexes.The authors acknowledge the Comisió lnterdepartamental de Recerςa i lnnovació Tecnologica (CIRIT, project QFN94-4619) for financial support and the Ministerio de Educación y Ciencia for a studentship (MAH.

Testing a Microarray to Detect and Monitor Toxic Microalgae in Arcachon Bay in France

Harmful algal blooms (HABs) occur worldwide, causing health problems and economic damages to fisheries and tourism. Monitoring agencies are therefore essential, yet monitoring is based only on time-consuming light microscopy, a level at which a correct identification can be limited by insufficient morphological characters. The project MIDTAL (Microarray Detection of Toxic Algae)—an FP7-funded EU project—used rRNA genes (SSU and LSU) as a target on microarrays to identify toxic species. Furthermore, toxins were detected with a newly developed multiplex optical Surface Plasmon Resonance biosensor (Multi SPR) and compared with an enzyme-linked immunosorbent assay (ELISA). In this study, we demonstrate the latest generation of MIDTAL microarrays (version 3) and show the correlation between cell counts, detected toxin and microarray signals from field samples taken in Arcachon Bay in France in 2011. The MIDTAL microarray always detected more potentially toxic species than those detected by microscopic counts. The toxin detection was even more sensitive than both methods. Because of the universal nature of both toxin and species microarrays, they can be used to detect invasive species. Nevertheless, the MIDTAL microarray is not completely universal: first, because not all toxic species are on the chip, and second, because invasive species, such as Ostreopsis, already influence European coasts

Microfluidic technology for plankton research

Plankton produces numerous chemical compounds used in cosmetics and functional foods. They also play a key role in the carbon budget on the Earth. In a context of global change, it becomes important to understand the physiological response of these microorganisms to changing environmental conditions. Their adaptations and the response to specific environmental conditions are often restricted to a few active cells or individuals in large populations. Using analytical capabilities at the subnanoliter scale, microfluidic technology has also demonstrated a high potential in biological assays. Here, we review recent advances in microfluidic technologies to overcome the current challenges in high content analysis both at population and the single cell level

Modelo alternativo de intervención para alumnos con necesidades educativas especiales en la etapa de Educación Secundaria Obligatoria : aplicación en el aula

El proyecto consiste en elaborar propuestas pedagógicas y curriculares de atención a la diversidad para alumnos con necesidades educativas especiales. Se trata de que la permanencia en el centro se convierta en una oportunidad real de acceso a la educación. Los objetivos son reflexionar sobre las características y factores que condicionan el proceso de aprendizaje en los alumnos con n.e.e. en la etapa de la ESO; revisar la normativa vigente sobre la intervención con a.c.n.e.e.s; diseñar un modelo de intervención alternativo para dar una respuesta educativa más idónea a los a.c.n.e.e.s de esta etapa, atendiendo a las características de los alumnos, de la etapa y del centro; proponer una nueva organización de las áreas curriculares. En el aula se aplica una metodología activa para potenciar las distintas capacidades de los alumnos. Las actividades son elaborar el proyecto base y propuestas didácticas concretas para su aplicación; el trabajo con el grupo de alumnos consiste en el desarrollo por separado de cada una de las áreas, con el fin de trabajar de modo sistemático los objetivos y contenidos más básicos e instrumentales de cada una de ellas; desarrollo de una unidad didáctica interdisciplinar sobre el 'Estudio del Parque de Polvoranca' y desarrollo de actividades posteriores que permiten concluir este estudio sobre un entorno natural des de los distintos puntos de vista. La evaluación valora el proceso de aprendizaje de cada alumno incluido en esta modalidad de apoyo para valorar los posibles beneficios aportados por este modelo de trabajo. Se incluye como anexos un sociograma y varios cuestionarios para los padres de los alumnos, para los alumnos y para los profesores. El proyecto se completa con un disquete con la valoración final del P.I..Madrid (Comunidad Autónoma). Consejería de EducaciónMadridMadrid (Comunidad Autónoma). Subdirección General de Formación del Profesorado. CRIF Las Acacias; General Ricardos 179 - 28025 Madrid; Tel. + 34915250893ES

Guía de auxiliares de conversación en Francia 2020

En la pantalla de tít. del PDF: Embajada de España en Francia, Consejería de EducaciónGuía concebida como apoyo al programa de auxiliares de conversación en Francia. Incluye informaciones administrativas, culturales y pedagógicas, direcciones de organismos franceses y españoles, y otros datos de interés, todos ellos de gran ayuda para los nuevos auxiliares que se incorporan cada curso escolar a Francia. Dado el importante objetivo que los auxiliares tienen encomendado en relación con la promoción de la lengua y cultura españolas en Francia, la información ha sido revisada y actualizada, para publicación y difusión en línea de una nueva edición de la guía.ES

High-Content Screening of Plankton Alkaline Phosphatase Activity in Microfluidics

One way for phytoplankton to survive orthophosphate depletion is to utilize dissolved organic phosphorus by expressing alkaline phosphatase. The actual methods to assay alkaline phosphate activity—either in bulk or as a presence/absence of enzyme activity—fail to provide information on individual living cells. In this context, we develop a new microfluidic method to compartmentalize cells in 0.5 nL water-in-oil droplets and measure alkaline phosphatase activity at the single-cell level. We use enzyme-labeled fluorescence (ELF), which is based on the hydrolysis of ELF-P substrate, to monitor in real time and at the single-cell level both qualitative and quantitative information on cell physiology (i.e., localization and number of active enzyme sites and alkaline phosphatase kinetics). We assay the alkaline phosphatase activity of Tetraselmis sp. as a function of the dissolved inorganic phosphorus concentration and show that the time scale of the kinetics spans 1 order of magnitude. The advantages of subnanoliter-scale compartmentalization in droplet-based microfluidics provide a precise characterization of a population with single-cell resolution. Our results highlight the key role of cell physiology to efficiently access dissolved organic phosphorus.Initiative d'excellence de l'Université de Bordeau

Variable inter and intraspecies alkaline phosphatase activity within single cells of revived dinoflagellates

Adaptation of cell populations to environmental changes is mediated by phenotypic variability at the single-cell level. Enzyme activity is a key factor in cell phenotype and the expression of the alkaline phosphatase activity (APA) is a fundamental phytoplankton strategy for maintaining growth under phosphate-limited conditions. Our aim was to compare the APA among cells and species revived from sediments of the Bay of Brest (Brittany, France), corresponding to a pre-eutrophication period (1940’s) and a beginning of a post-eutrophication period (1990’s) during which phosphate concentrations have undergone substantial variations. Both toxic marine dinoflagellate Alexandrium minutum and the non-toxic dinoflagellate Scrippsiella acuminata were revived from ancient sediments. Using microfluidics, we measured the kinetics of APA at the single-cell level. Our results indicate that all S. acuminata strains had significantly higher APA than A. minutum strains. For both species, the APA in the 1990’s decade was significantly lower than in the 1940’s. For the first time, our results reveal both inter and intraspecific variabilities of dinoflagellate APA and suggest that, at a half-century timescale, two different species of dinoflagellate may have undergone similar adaptative evolution to face environmental changes and acquire ecological advantages.

Dynamics of microbial communities across the three domains of life over an annual cycle with emphasis on marine mucilage in the Southern Bay of Biscay resolved by microbial fingerprinting

International audienceMarine mucilage has been described as worldwide phenomena occurring sporadically, or frequently in certain coastal areas. They are transitory phenomena that can remain in the photic zone for several days or weeks. Their occurrence has been more frequent and persistent, and their magnitude has increased during the last decades. Their formation typically reflects an imbalance in the marine microbial communities, and has frequently be linked to global changes. Recurrent marine mucilage events have been observed in recent years in the Southern Bay of Biscay near the French coast, mainly south of the Adour estuary. In this study, we used a fingerprinting method (T-RFLP) targeting 16S and 18S rRNA genes to investigate marine microbial community composition and dynamics over an annual cycle across the three domains of life in coastal water at three depths, in the Adour River upstream of the mouth and in the marine mucilage. In line with studies conducted in marine environments we highlighted that the dynamics of marine microbial communities in the Bay of Biscay coincided with two environmental contexts: winter and spring on one hand and summer and autumn on the other hand. More interestingly, this dynamics affects also the marine pelagic mucilage that was observed during the sampling campaigns. Thus, the composition of the marine mucilage that appears in winter/spring context diverges from the composition of the marine mucilage that occurred during the summer/autumn context. We highlighted also that marine microbial communities were partly different from marine mucilage communities with an enrichment of some microorganisms suggesting that marine mucilage behaves as a microhabitat in seawater and possesses distinct microbial assemblages from the surrounding communities

Pelagic food web patterns: do they modulate virus and nanoflagellate effects on picoplankton during the phytoplankton spring bloom?

International audienceAs agents of mortality, viruses and nanoflagellates impact on picoplankton populations. We examined the differences in interactions between these compartments in two French Atlantic bays. Microbes, considered here as central actors of the planktonic food web, were first monitored seasonally in Arcachon (2005) and Marennes-Oléron (2006) bays. Their dynamics were evaluated to categorize trophic periods using the models of Legendre and Rassoulzadegan (1995) as a reference framework. Microbial interactions were then compared through 48h-batch-culture experiments performed during the phytoplankton spring bloom, identified as herbivorous in Marennes and multivorous in Arcachon. Marennes was spatially homogeneous compared to Arcachon. The former was potentially more productive, featuring a large number of heterotrophic pathways, while autotrophic mechanisms dominated in Arcachon. A link was found between viruses and phytoplankton in Marennes, suggesting a role of virus in the regulation of autotroph biomass. Moreover, the virus-bacteria relation was weaker in Marennes, with a bacterial lysis potential of 2.6% compared with 39% in Arcachon. The batch experiments (based on size- fractionation and viral enrichment) revealed different microbial interactions that corresponded to the spring-bloom trophic interactions in each bay. In Arcachon, where there is a multivorous web, flagellate predation and viral lysis acted in an opposite way on picophytoplankton. When together they both reduced viral production. Conversely, in Marennes (herbivorous web), flagellates and viruses together increased viral production. Differences in the composition of the bacterial community composition explained the combined flagellate-virus effects on viral production in the two bays