1,721,261 research outputs found
Biofilm cultures to understand Ostreopsis benthic HABs
No full textBIOFILM CULTURES TO UNDERSTAND OSTREOPSIS BENTHIC HABS
Roberta Congestri1 ([email protected]), Francesca Di Pippo2 ([email protected]), Patrizia Albertano1 ([email protected])
1University of Rome “Tor Vergata”, Department of Biology, LBA- Laboratory of Biology of Algae, Via della Ricerca scientifica, 00133 Rome, 2CNR–IAMC, National Research Council, Institute for Coastal Marine Environment, Località Sa Mardini, Torregrande, 09072 Oristano, Italy.
An incubator prototype specially designed for culturing aquatic phototrophic biofilms on substrata at controlled environmental conditions was used to perform semi-continuous flow microcosm experiments with microphytobenthos sampled during toxic Ostreopsis ovata outbreaks in summer along the middle Tyrrhenian Sea coast. The system provided the possibility of simultaneously controlling environmental conditions and co-culturing biofilm organisms on a set of artificial substrata in a closed photobioreactor, providing a realistic assessment of community processes and maintaining biofilm integrity during sampling. The design allowed to study the effect of time, site, substratum of in situ growth and the role of key species in community development starting from natural inocula, cultured on polycarbonate slides, in a moving film of K/2 medium (50 L h-1 flow velocity) under controlled temperature (25°C) and light conditions (110 mol photons m-2s-1). Benthic dinoflagellates, diatoms and filamentous cyanobacteria constituted significant fractions, in taxon richness and biomass, of the natural biofilms formed on macroalgae and bryozoans used as inocula. Biofilm cells were all embedded in a common mucilage matrix (EPS, exopolymeric substances). Non-destructive, real time monitoring of biomass accumulation was obtained by recordings of transmittance values by light sensors positioned under the slides. Growth curves indicated that biofilms reached a mature stage in 40 to 50 days. Species accrual, growth and compositional shifts over time were monitored using a variety of microscopical technique, including confocal laser scanning microscopy. Initial adhesion and substratum colonisation appeared as stochastic processes, then community structure and physiognomy, especially of the photosynthetic fraction, visibly changed with time. Prevalence of cyanobacteria at late growth stages was detected in all cultures, which showed complex layering, inner voids and channels. HPLC on matrix sugars revealed variations in total amounts and composition. No toxic compounds were detected in the final communities tested by LC-MS and MALDI-TOF MS techniques
Cytochemistry and ultrastructure of capsules in two Chroococcalean cyanobacteria from Roman catacombs.
No full textPhototrophic biofilms in wastewaters: application of transmission electron microscopy techniques to bioremediation studies.
No full text
Annual photosynthetic response of phototrophic biofilms from an Italian wastewater treatment plant.
No full textAlbertano da Brescia - Paris, Sorbonne Nouvelle - 4 Giugno 2016
No full textCiclo di Seminari del CERLIM (Centre d’Études et de Recherche sur la Littérature Italienne du Moyen Âge). Le Silence. Seduta del 4 giugno 2016 (salle 125, centre Censier, Sorbonne Nouvelle, 1 rue Censier 75005 PARIS): Anna Fontes Baratto et Antonio Montefusco: Albertano da Brescia tra Italia ed Europa
Cytomorphological and genetic characterization of troglobitic Leptolyngbya strains isolated from roman hypogea
No full textSix Leptolyngbya strains, isolated from the archaeological surfaces of hypogean sites, were phenotypically and genetically characterized by light and electron microscopy and 16S rRNA gene and 16S-23S internally transcribed spacer (ITS) sequencing. Three phycoerythrin-rich (red) and three phycocyanin-rich (green) isolates were assigned to different operational taxonomic units (OTUs). Among the green isolates, one strain showed an OTU intraspecific variation due to differences in the ITS sequences and genomic polymorphism. Within the ITS sequence, variable regions, conserved domains and tRNAIle and tRNAAla genes showed high sequence identity among the phylotypes. Together, these data indicated a relatedness of the six strains to other Leptolyngbya from subaerophytic and geothermal environments and allowed the definition of novel Leptolyngbya OTUs
Un nuovo testimone del “ramo palatino” dei volgarizzamenti del "De doctrina dicendi et tacendi" di Albertano da Brescia
No full textIl contributo prende in considerazione la versione toscana anonima del Liber de doctrina dicendi et tacendi di Albertano da Brescia tràdita dal ms. Fi BNC Magl. XXXVIII 127. A partire dalla descrizione del cod. e dall’analisi linguistica della sezione contenente il volgarizzamento del trattato in forma “scorciata”», si ricostruiscono i suoi rapporti con gli altri mss. latori del medesimo testo e con l’edizione curata dall’Accademico della Crusca Bastiano de’ Rossi nel 1610. Si conclude con l’illustrazione delle future prospettive di ricerca.The paper considers the anonymous Tuscan version of the Liber de doctrina dicendi et tacendi by Albertano da Brescia, transmitted by the manuscript Fi BNC Magl. XXXVIII, 127. The author describes the codex and provides a linguistic analysis of the section containing the vernacular shortened version of the treatise. The relationships between the manuscripts which transmit the same text and the critical edition by the Crusca Academician Bastiano de’ Rossi are then reconstructed. The paper proceeds with an illustration of the research prospects
- …
