Séminaires de formation à la recherche en Afrique (SéFRA)

Jean-Claude Penrad, maître de conférencesEmmanuel Grégoire, Marie-France Lange, directeurs de recherche à l’IRDBenoît Hazard, chargé de recherche au CNRS Cet enseignement pluridisciplinaire de formation à la recherche par la recherche s’appuie sur des travaux récents ou en cours et privilégie les méthodes et les pratiques de terrain. Au cours de cette année universitaire, treize séances (soit 26 heures) ont eu lieu dont trois ont été consacrées aux exposés des étudiants. Dans une première séa..

Séminaires de formation à la recherche en Afrique (SéFRA)

Jean-Claude Penrad, maître de conférencesEmmanuel Grégoire, directeur de recherche à l’IRDBenoit Hazard, chargé de recherche au CNRS Cet enseignement pluridisciplinaire de formation à la recherche par la recherche s’appuie sur des travaux récents ou en cours et privilégie les méthodes et les pratiques de terrain. Au cours de cette année universitaire, douze séances ont eu lieu dont deux consacrées aux seuls exposés des étudiants. Après une première séance de présentation du séminaire assurée ..

Beneficial effects of reconstituted high-density lipoprotein (rHDL) on circulating CD34+ cells in patients after an acute coronary syndrome

Background: High-density lipoproteins (HDL) favorably affect endothelial progenitor cells (EPC). Circulating progenitor cell level and function are impaired in patients with acute coronary syndrome (ACS). This study investigates the short-term effects of reconstituted HDL (rHDL) on circulating progenitor cells in patients with ACS. Methods and Findings: The study population consisted of 33 patients with recent ACS: 20 patients from the ERASE trial (randomized to receive 4 weekly intravenous infusions of CSL-111 40 mg/kg or placebo) and 13 additional patients recruited as controls using the same enrolment criteria. Blood was collected from 16 rHDL (CSL-111)-treated patients and 17 controls at baseline and at 6–7 weeks (i.e. 2–3 weeks after the fourth infusion of CSL-111 in ERASE). CD34+ and CD34+/kinase insert domain receptor (KDR+) progenitor cell counts were analyzed by flow cytometry. We found preserved CD34+ cell counts in CSL-111-treated subjects at follow-up (change of 1.6%), while the number of CD34+ cells was reduced (-32.9%) in controls (p = 0.017 between groups). The level of circulating SDF-1 (stromal cell-derived factor-1), a chemokine involved in progenitor cell recruitment, increased significantly (change of 21.5%) in controls, while it remained unchanged in CSL-111-treated patients (p = 0.031 between groups). In vitro exposure to CSL-111 of early EPC isolated from healthy volunteers significantly increased CD34+ cells, reduced early EPC apoptosis and enhanced their migration capacity towards SDF-1. Conclusions: The relative increase in circulating CD34+ cells and the low SDF-1 levels observed following rHDL infusions in ACS patients point towards a role of rHDL in cardiovascular repair mechanisms

Hydrogenation of solid hydrogen cyanide HCN and methanimine CH2NH at low temperature

International audienceContext. Hydrogenation reactions dominate grain surface chemistry in dense molecular clouds and lead to the formation of complex saturated molecules in the interstellar medium. Aims. We investigate in the laboratory the hydrogenation reaction network of hydrogen cyanide HCN. Methods. Pure hydrogen cyanide HCN and methanimine CH2NH ices are bombarded at room temperature by H-atoms in an ultra-high vacuum experiment. Warm H-atoms are generated in an H2 plasma source. The ices are monitored with Fourier-transform infrared spectroscopy in reflection absorption mode. The hydrogenation products are detected in the gas phase by mass spectroscopy during temperature-programmed desorption experiments. Results. HCN hydrogenation leads to the formation of methylamine CH3NH2, and CH2NH hydrogenation leads to the formation of methylamine CH3NH2, suggesting that CH2NH can be a hydrogenation-intermediate species between HCN and CH3NH2. Conclusions. In cold environments the HCN hydrogenation reaction can produce CH3NH2, which is known to be a glycine precursor, and to destroy solid-state HCN, preventing its observation in molecular clouds ices

The “Who?” Question in the Hate Speech Debate: Part 1: Consistency, Practical, and Formal Approaches

This two-part article addresses the “Who?” question in the hate speech debate: namely, which characteristics, social identities or statuses should or should not be treated as protected characteristics within a body of hate speech laws? Using United Kingdom incitement to hatred laws as a focal point, the article outlines and critically appraises five broad approaches to specification. Part 1 deals with consistency specification, which highlights norms of consistency both within incitement to hatred law itself and in relation to other laws, practical specification, which focuses on the ostensible goals or apparent aims of incitement to hatred laws, and formal specification, which looks at the formal qualities of the characteristics themselves and to the different forms of people’s relationships with those characteristics. And Part 2 considers functional specification, which concentrates on the underlying or real functions, purposes or objectives of incitement to hatred laws, and democratic specification, which appeals to democratic procedures as well as to democratic values, norms and principles that speak to the proper scope of incitement to hatred laws. Along the way I shall also critically assess a range of substantive arguments about which particular characteristics should or should not be covered by incitement to hatred laws given the aforementioned approaches. My main conclusion shall be that each of the approaches has its strengths and weakness and that, partly because of this, no single approach is adequate by itself as a tool for specifying the proper scope of incitement to hatred laws, but also, by the same token, no approach should be ruled out entirely. Instead, the best strategy is one that combines together all five approaches in reasonable ways given the law, the characteristic and the context

Organisation d'un débat en classe sur les OGM en utilisant un corpus médiatique

Publication de l'IREM de Montpellier - production du groupe Enseignement ScientifiqueLes questions scientifiques socialement vives (QSSV) se rapportent en général à des savoirs de référence non stabilisés : il existe des débats (des controverses) entre spécialistes des champs disciplinaires impliqués, débats qui s'élargissent généralement à la sphère politique et conduisent à des débats de société. Les QSSV font l'objet de nombreuses recherches en sciences de l'éducation, qui mettent en avant différents enjeux éducatifs parmi lesquels former à l’exercice d’une citoyenneté scientifique et motiver les apprentissages scientifiques grâce à la contextualisation produite par les QSSV. Dans un tel contexte, l'équipe IREM « Enseignement Scientifique » a élaboré un scénario pédagogique interdisciplinaire, en choisissant pour thème les OGM et plus précisément la récente controverse Séralini (septembre 2012), fortement médiatisée. L'activité, d’une durée totale de 4 heures, se déroule en deux temps : d’abord l’étude, par petits groupes d’élèves, d’un corpus de textes organisé selon différents axes, puis un débat en classe à l’aide d’un protocole de débat approprié aux objectifs d’apprentissage. Le scénario a été expérimentée à deux reprises au lycée Jules Guesde de Montpellier. La présente ressource vise à rendre compte de cette innovation pédagogique et didactique tout en fournissant aux enseignants de mathématiques, SPC et SVT tout le matériel nécessaire à sa reproduction

Vocabulaire scientifique et explicitation des démarches

Publication de l'IREM de Montpellier - production du groupe Enseignement ScientifiqueCette ressource répond à un triple objectif : vérifier l’acquisition du vocabulaire scientifique de base, amener l’élève à expliciter par lui-même la nature des démarches qu’il mène en cours de sciences, des études montrant que le recul réflexif ainsi produit contribue à donner du sens à l’apprentissage, enfin, par l’explicitation croisée des démarches, promouvoir un dialogue entre les trois disciplines scientifiques à même de faciliter des pratiques interdisciplinaires futures. Le point de départ est une grille conceptuelle constituée de mots clefs : majoritairement desverbes (conjecturer, expérimenter, observer, manipuler, calculer, prouver, communiquer, ...) et quelques noms (problème, hypothèse, lois, théorèmes, théories, ...). Cette grille épistémologique est fournie à l’élève sous la forme ludique de grille de mots croisés. Les élèves, en petits groupes tentent de remplir la grille de mots croisés scientifiques proposée. La mise en commun permet de définir les principaux mots du langage scientifique utilisés en classe de seconde dans les différentes disciplines scientifiques. Une fiche récapitulative de ce lexique est distribuée en fin de séquence. Lors d'une deuxième séquence, il est demandé aux élèves, en petits groupes, d'annoter des extraits de cahiers de recherches ou de compte-rendus de TP, à l’aide de ces mots clefs : là j’observe, ici je prouve, là je réfute,... Les réponses proposées par les élèves sont discutées en classe entière avec les enseignants. Un compte-rendu d’expérimentation détaillé figure dans la fiche professeur de la ressource. Ilmontre le potentiel d’une telle activité qui a suscité beaucoup d’enthousiasme au sein d’une classe constituée d’élèves initialement peu volontaires, peu intéressés et relativement faibles en sciences. Divers prolongements sont proposés et feront l’objet d’expérimentations ultérieures

Scientific Opinion on the pest categorisation of Strawberry vein banding virus

The Panel on Plant Health performed a pest categorisation of Strawberry vein banding virus (SVBV) for the European Union (EU) territory. SVBV is a well-defined virus species of the genus Caulimovirus for which the entire genome sequence is known and molecular detection assays are available. SVBV is transmitted by vegetative multiplication of infected hosts and through the activity of aphid vectors, the most efficient being Chaetosiphon spp. The virus is reported from all continents and is present in three EU Member States: the Czech Republic, Italy and Slovakia. The host range of SVBV is restricted to cultivated and wild strawberries. It is listed in Annex IAI of Directive 2000/29/EC. SVBV is not expected to be affected by ecoclimatic conditions wherever its hosts are present and has the potential to establish in large parts of the EU territory, and to subsequently spread through the action of its Chaetosiphon fragaefolii vector, which is present in many Member States. SVBV does not cause severe symptoms, and modern cultivars are mostly symptomless if infected with SVBV alone. SVBV can, however, contribute to more severe symptoms when it occurs in mixed infections with other strawberry viruses. Despite this, SVBV is considered a minor problem in strawberry production as a consequence of modern practices including the systematic use of certified planting materials and the use of short crop cycles, which have greatly reduced the impact of strawberry viruses. Overall, SVBV does not have the potential to be a quarantine pest as, given current agricultural practices, it does not fulfil the pest categorisation criteria defined in the International Standards for Phytosanitary Measures No 11 of having a severe impact. However, SVBV has the potential to be a regulated non-quarantine pest because it fulfils all pest categorisation criteria defined in the International Standards for Phytosanitary Measures No 21

Scientific Opinion on the pest categorisation of Eotetranychus lewisi

The Panel on Plant Health performed a pest categorisation of the Lewis spider mite, Eotetranychus lewisi, for the European Union (EU). The Lewis spider mite is a well-defined and distinguishable pest species that has been reported from a wide range of hosts, including cultivated species. Its distribution in the EU territory is restricted to (i) Madeira in Portugal; and to (ii) Poland where few occurrences were reported in glasshouses only. The pest is listed in Annex IIAI of Council Directive 2000/29/EC. A potential pathway of introduction and spread is plants traded from outside Europe and between Member States. The Lewis spider mite has the potential to establish in most part of the EU territory based on climate similarities with the distribution area outside the EU and the widespread availability of hosts present both in open fields and in protected cultivations. With regards to the potential consequences, one study is providing quantitative data on impact showing that the pest can reduce yield and affect quality of peaches and poinsettias, and only few studies describe the general impact of the pest on cultivated hosts. Although chemical treatments are reported to be effective in controlling the Lewis spider mite, it is mentioned as a growing concern for peaches, strawberries, raspberries and vines in the Americas. Overall, Eotetranychus lewisi meets the pest categorisation criteria defined in the International Standards for Phytosanitary Measures No 11 for a quarantine pest and in No 21 for a regulated non-quarantine pest

Scientific Opinion on the pest categorisation of Ditylenchus destructor Thorne

The Panel on Plant Health performed a pest categorisation of Ditylenchus destructor, the potato rot nematode. D. destructor is listed in Annex II, Part A, Section II of Council Directive 2000/29/EC as a harmful organism known to occur in the Union and relevant for the entire Union. D. destructor is a distinct taxonomic entity that can be identified in a straightforward way, and which is present in the majority of EU member states, although sporadically (but data from systematic surveys are lacking). Many hosts of D. destructor are present in the RA area and the climatic conditions in the whole risk assessment area are favourable for the completion of the pest life cycle. D. destructor can cause significant damage to the below-ground parts (roots, tubers, bulbs) of host crops such as potato and several ornamental plants. However, during recent decades only minor damage has been reported (except in some Eastern European countries). Plants for planting are a pathway for introduction and spread of D. destructor, which may cause severe impacts on the intended use of the plants for planting