The Persuasive and the Convincing: In Search of a Functional Characterization of Educational Interventions in Science

Addressed to professionals and researchers, this article proposes a reflection on the issues and risks associated with certain uses of labels that allow qualification of tested, promoted or contested pedagogical practices and interventions in science education. Often paired in dichotomies, these labels are here presented as sometimes generating credibility problems for research efforts that invoke them, as well as misunderstandings and prejudices when imprudently invoked in teacher training. The article thus proposes an original, dichotomous, and functional formula for characterizing educational efforts, drawing on the ordinary difference in everyday language between persuasion and conviction

Comparaison des communautés de picoeucaryotes marins arctiques par des méthodes moléculaires et biais se rattachant à ces techniques

Les picoeucaryotes (les eucaryotes dont la taille < 3um) arctiques sont reconnus depuis quelques années pour être importants pour la production primaire et le maintien de l'intégrité globale des écosystèmes marins. Par contre, leur petite taille les rend difficiles à distinguer par des techniques de microbiologie traditionnelles comme la microscopie. Afin de pallier à ces limitations et d'étudier ces microorganismes directement dans leur environnement, on a maintenant recours à des méthodes moléculaires, qui sont par contre reconnues pour introduire un biais dans l'obtention des résultats. Afin d'améliorer ces t e c h n i q u e s , l ' i m p o r t a n c e de ce biais a été étudiée à l'aide d'espèces cultivées et d'échantillons environnementaux pélagiques arctiques. A la lumière de ces résultats, les communautés de picoeucaryotes arctiques présentes à la côte et au large de la mer de Beaufort ont été comparées afin de mieux comprendre leur dispersion et leur rôle dans l'environnement

Rapid on-site detection of harmful algal blooms: real-time cyanobacteria identification using Oxford Nanopore sequencing

With the increasing occurrence and severity of cyanobacterial harmful algal blooms (cHAB) at the global scale, there is an urgent need for rapid, accurate, accessible, and cost-effective detection tools. Here, we detail the RosHAB workflow, an innovative, in-the-field applicable genomics approach for real-time, early detection of cHAB outbreaks. We present how the proposed workflow offers consistent taxonomic identification of water samples in comparison to traditional microscopic analyses in a few hours and discuss how the generated data can be used to deepen our understanding on cyanobacteria ecology and forecast HABs events. In parallel, processed water samples will be used to iteratively build the International cyanobacterial toxin database (ICYATOX; http://icyatox.ibis.ulaval.ca) containing the analysis of novel cyanobacterial genomes, including phenomics and genomics metadata. Ultimately, RosHAB will (1) improve the accuracy of on-site rapid diagnostics, (2) standardize genomic procedures in the field, (3) facilitate these genomics procedures for non-scientific personnel, and (4) identify prognostic markers for evidence-based decisions in HABs surveillance

Le persuasif et le convaincant : pour une caractérisation fonctionnelle des interventions éducatives en sciences

Cet article propose une réflexion sur les problèmes et risques associés à certaines utilisations d’étiquettes permettant de qualifier les pratiques et les interventions pédagogiques testées, promues ou contestées dans le cadre de l’enseignement des sciences. Souvent pairées en dichotomies, ces étiquettes sont parfois présentées comme pouvant générer des problèmes de crédibilité des recherches qui les utilisent, ainsi que des incompréhensions et des blessures lorsqu’invoquées imprudemment en formation. Il propose ensuite une formule dichotomique et fonctionnelle permettant de caractériser les efforts éducatifs en prenant appui sur la différence ordinaire qui existe dans le langage courant entre la persuasion et la conviction

Diversity of planktonic microorganisms in the Arctic Ocean

Special issue Overarching perspectives of contemporary and future ecosystems in the Arctic Ocean.-- 11 pages, 7 figures, 1 tableThe present paper begins by reviewing recent developments in our understanding of the diversity of planktonic microorganisms in the Arctic Ocean, taking into account recent data from high throughput sequencing techniques. This data has enabled deeper analysis of the many thousands of different microorganisms present in natural samples. The Arctic Ocean is similar to the other oceans in terms of the abundance and general composition of microbial communities. However, some traits are unique. For example, there are essentially no cyanobacteria in the Arctic and their ecological role seems to be taken up by picoeukaryotic algae. Recent comparisons of the bacterial communities from the two Polar oceans with those from temperate waters showed that Polar communities were closer to each other than to the lower latitude ones. However, they only shared about 15% of the taxa. Newer data considerably increases the coverage of Arctic sites sampled and indicates that bacterial communities in the Arctic vary significantly across regions and seasons. In particular several recent cruises have provided access to the Arctic Ocean during the winter, the least known season and we review two instances of active microbes during the winter. First a bloom of Thaumarchaeota that may have been based on the use of urea as a source of carbon and reducing power, and second the increase in picoeukaryotic algae as soon as light reaches the ocean in February. Both examples show that there is considerable microbial activity during the Polar winterThis is a contribution to ArcticNet and Québec Ocean, which is supported by the Fonds de Recherche du Québec. CPA was funded by grants BOREAL (CLG2007-28872-E/ANT) and MarineGems (CTM2010-20361) from the Spanish Ministry of Science and InnovationPeer Reviewe

Archaeal amoA and ureC genes and their transcriptional activity in the Arctic Ocean

International audienceThaumarchaeota and the gene encoding for a subunit of ammonia monooxygenase (amoA) are ubiquitous in Polar Seas, and some Thaumarchaeota also have a gene coding for ureC, diagnostic for urease. Using quantitative PCR we investigated the occurrence of genes and transcripts of ureC and amoA in Arctic samples from winter, spring and summer. AmoA genes, ureC genes and amoA transcripts were always present, but ureC transcripts were rarely detected. Over a 48 h light manipulation experiment amoA transcripts persisted under light and dark conditions, but not ureC transcripts. In addition, maxima for amoA transcript were nearer the surface compared to amoA genes. Clone libraries using DNA template recovered shallow and deep amoA clades but only the shallow clade was recovered from cDNA (from RNA). These results imply environmental control of amoA expression with direct or indirect light effects, and rare ureC expression despite its widespread occurrence in the Arctic Ocean

Distribution, phylogeny, and growth of cold-adapted Picoprasinophytes in Arctic Seas

12 pages, 7 figures, 2 tablesOur pigment analyses from a year-long study in the coastal Beaufort Sea in the western Canadian Arctic showed the continuous prevalence of eukaryotic picoplankton in the green algal class Prasinophyceae. Microscopic analyses revealed that the most abundant photosynthetic cell types were Micromonas-like picoprasinophytes that persisted throughout winter darkness and then maintained steady exponential growth from late winter to early summer. A Micromonas (CCMP2099) isolated from an Arctic polynya (North Water Polynya between Ellesmere Island and Greenland), an ice-free section, grew optimally at 61C–81C, with light saturation at or below 10 lmol photons .m-2 . s-1 at 0ºC. The 18S rDNA analyses of this isolate and environmental DNA clone libraries from diverse sites across the Arctic Basin indicate that this single psychrophilic Micromonas ecotype has a pan-Arctic distribution. The 18S rDNA from two other picoprasinophyte genera was also found in our pan-Arctic clone libraries: Bathycoccus and Mantoniella. The Arctic Micromonas differed from genotypes elsewhere in the World Ocean, implying that the Arctic Basin is a marine microbial province containing endemic species, consistent with the biogeography of its macroorganisms. The prevalence of obligate low-temperature, shade-adapted species in the phytoplankton indicates that the lower food web of the Arctic Ocean is vulnerable to ongoing climate change in the regionThis research was supported by the Natural Sciences and Engineering Research Council of Canada; the Strategic Science Fund from Fisheries and Oceans, Canada; the Japan Marine Science and Technology Center, Tokyo, Japan; the Canada Climate Action Fund; ARTIC (REN2001-4909-E/ANT, MCyT) and ESTRAMAR (CTM2004-12631/MAR, MEC) Spain; GENmMar (CTM2004-02586/MAR), European Union; and Fonds québécois de recherche sur la nature et la technologie, Québec, CanadaPeer reviewe

Genetic diversity of Salmonella enterica isolated over 13 years from raw California almonds and from an almond orchard.

A comparative genomic analysis was conducted for 171 Salmonella isolates recovered from raw inshell almonds and raw almond kernels between 2001 and 2013 and for 30 Salmonella Enteritidis phage type (PT) 30 isolates recovered between 2001 and 2006 from a 2001 salmonellosis outbreak-associated almond orchard. Whole genome sequencing was used to measure the genetic distance among isolates by single nucleotide polymorphism (SNP) analyses and to predict the presence of plasmid DNA and of antimicrobial resistance (AMR) and virulence genes. Isolates were classified by serovars with Parsnp, a fast core-genome multi aligner, before being analyzed with the CFSAN SNP Pipeline (U.S. Food and Drug Administration Center for Food Safety and Applied Nutrition). Genetically similar (≤18 SNPs) Salmonella isolates were identified among several serovars isolated years apart. Almond isolates of Salmonella Montevideo (2001 to 2013) and Salmonella Newport (2003 to 2010) differed by ≤9 SNPs. Salmonella Enteritidis PT 30 isolated between 2001 and 2013 from survey, orchard, outbreak, and clinical samples differed by ≤18 SNPs. One to seven plasmids were found in 106 (62%) of the Salmonella isolates. Of the 27 plasmid families that were identified, IncFII and IncFIB plasmids were the most predominant. AMR genes were identified in 16 (9%) of the survey isolates and were plasmid encoded in 11 of 16 cases; 12 isolates (7%) had putative resistance to at least one antibiotic in three or more drug classes. A total of 303 virulence genes were detected among the assembled genomes; a plasmid that harbored a combination of pef, rck, and spv virulence genes was identified in 23% of the isolates. These data provide evidence of long-term survival (years) of Salmonella in agricultural environments