1,454 research outputs found
The EMSO-Azores deep sea observatory: 8 years of operation
The EMSO-Azores deep sea observatory is a component of the EMSO ERIC. It focuses on two main questions: What are the feedbacks between volcanism, deformation, seismicity, and hydrothermalism at a slow spreading mid-ocean ridge and how does the hydrothermal ecosystem couple with these sub-seabed processes? The infrastructure comprises 2 sea monitoring nodes, autonomous instruments and a set of site studies experiments. It has been deployed in 2010 in the Lucky Strike vent field and acquires multidisciplinary data since then.Peer Reviewe
Control of anthocyanin biosynthesis pathway gene expression by eutypine, a toxin from Eutypa lata, in grape cell tissue cultures
Eutypine, 4-hydroxy-3-(3-methyl-3-butene-1-ynyl) benzaldehyde, is a toxin produced by Eutypa lata,
the causal agent of Eutypa dieback in grapevine. The effect of the toxin on anthocyanin synthesis has
been investigated in Vitis vinifera cv. Gamay cell cultures. At concentrations higher than 200 μmol/L,
eutypine reduced anthocyanin accumulation in cells. The reduction in anthocyanin accumulation was
proportional to the eutypine concentrations and HPLC analysis showed that eutypine affected the
levels of all anthocyanins. The effect of eutypine application on the expression of five genes of the
anthocyanin biosynthesis pathway, including chalcone synthase (CHS), flavonone-3-hydroxylase
(F3H), dihydroflavonol 4-reductase (DFR), leucoanthocyanidin dioxygenase (LDOX), and UDP glucose-
flavonoid 3-O-glucosyl transferase (UFGT) was determined. Expression of CHS, F3H, DFR and
LDOX was not affected by the addition of eutypine to grapevine cell cultures. In contrast, expression
of the UFGT gene was dramatically inhibited by the toxin. These results suggest that in grapevine cell
cultures, eutypine strongly affects anthocyanin accumulation by inhibiting UFGT gene expression.
The mechanism of action of eutypine is discussed
Suivis et propositions d'expérimentations de techniques douces d'aménagement des berges sur la Lesse
Characterization of expressed sequence tags obtained by SSH during somatic embryogenesis in Cichorium intybus L
<p>Abstract</p> <p>Background</p> <p>Somatic embryogenesis (SE) is an asexual propagation pathway requiring a somatic-to-embryonic transition of differentiated somatic cells toward embryogenic cells capable of producing embryos in a process resembling zygotic embryogenesis. In chicory, genetic variability with respect to the formation of somatic embryos was detected between plants from a population of <it>Cichorium intybus </it>L. landrace Koospol. Though all plants from this population were self incompatible, we managed by repeated selfing to obtain a few seeds from one highly embryogenic (E) plant, K59. Among the plants grown from these seeds, one plant, C15, was found to be non-embryogenic (NE) under our SE-inducing conditions. Being closely related, we decided to exploit the difference in SE capacity between K59 and its descendant C15 to study gene expression during the early stages of SE in chicory.</p> <p>Results</p> <p>Cytological analysis indicated that in K59 leaf explants the first cell divisions leading to SE were observed at day 4 of culture. In contrast, in C15 explants no cell divisions were observed and SE development seemed arrested before cell reactivation. Using mRNAs isolated from leaf explants from both genotypes after 4 days of culture under SE-inducing conditions, an E and a NE cDNA-library were generated by SSH. A total of 3,348 ESTs from both libraries turned out to represent a maximum of 2,077 genes. <it>In silico </it>subtraction analysis sorted only 33 genes as differentially expressed in the E or NE genotype, indicating that SSH had resulted in an effective normalisation. Real-time RT-PCR was used to verify the expression levels of 48 genes represented by ESTs from either library. The results showed preferential expression of genes related to protein synthesis and cell division in the E genotype, and related to defence in the NE genotype.</p> <p>Conclusion</p> <p>In accordance with the cytological observations, mRNA levels in explants from K59 and C15 collected at day 4 of SE culture reflected differential gene expression that presumably are related to processes accompanying early stages of direct SE. The E and NE library obtained thus represent important tools for subsequent detailed analysis of molecular mechanisms underlying this process in chicory, and its genetic control.</p
Identification of mutations at the origin of various phenotypes in donkeys
Publiées depuis le début des années 1990, de nombreuses observations décrivent l'effet de mutations ponctuelles affectant les gènes responsables des différentes couleurs de la robe du cheval. Par contre, à ce jour, aucune étude n’a encore été consacrée à l’espèce asine, bien que celle-ci, en dépit de sa grande proximité phylogénique, présente des phénotypes très différents de ceux du cheval. Notre étude permet d’établir les bases génétiques de deux particularités : la robe à poils longs, caractéristique des Baudets du Poitou, et la décoloration observée autour du museau, des yeux et au niveau des membres et appelée Pangaré. Pour accomplir cette analyse, nous utilisons une approche par gènes candidats basée sur les données de la littérature concernant le cheval et d’autres espèces de mammifères. Par cette approche, nous mettons en évidence deux mutations dans le gène FGF5, toutes les deux responsables du phénotype poils longs, et une mutation dans le gène ASIP, associée au phénotype bouchard ou non pangaré.From 1990s, many results have described punctual mutations in the genes responsible for different
colors of dresses of horses, but to day no study had been achieved for the asinine species, which display
very different phenotypes although a close phylogenetic neighboring. Our study was designed
to try to establish the genetic basis of two features: the long hair dress found in Baudets du Poitou,
and the discoloration observed around the muzzle, eyes and limbs and which is called Light Point.
We have so adopted an approach by candidate genes from the existing literature in horses and other
mammals. By this approach two mutations have been identified in the gene FGF5 responsible for
the phenotype long hair and one mutation in the gene ASIP was associated with the phenotype No
Light Point
Weak intermolecular hydrogen and halogen interactions in an isomorphous halogen series of pseudoterpyridine ZnIIcomplexes
La VAE comme espace transitionnel : enjeux et paradoxes
Cette contribution vise à mieux cerner les logiques d’engagement psychique des candidats dans une démarche de VAE. Le cadre théorique envisagé est celui de la psychanalyse. Sont mobilisés plus particulièrement les travaux de Winnicott portant sur les caractéristiques de l’objet transitionnel identifié par cet auteur, afin de décrire et mieux comprendre les logiques d’investissement des candidats dans le dispositif de la VAE. Cet article s’appuie sur une recherche qualitative menée pendant trois ans dans le cadre d’une pratique de la VAE au sein de deux universités. Afin de recueillir des données sur la manière dont les candidats s’impliquent, trente-cinq candidatures de demande de VAE ont été étudiées. Cette recherche a permis de construire un modèle pour penser la manière dont les candidats se positionnent face à la transitionnalité inhérente au dispositif de VAE.This contribution aims at understanding better what leads candidates to apply for an Accreditation of Prior Learning (APL) for work experience, that can count toward a qualification. The theoretical framework we have used here is that of psychoanalysis. We have used, more specifically, the ideas developed by Winnicot about the characteristics of what he calls 'transitional objects', in order to describe and understand what can lead people to apply for this accreditation. This article is based on a qualitative research carried out for three years within a process of accreditation implemented in two universities. With a view to gathering data about the involvement of these applicants, we have studied thirty-five applications. This research allowed us to develop a model to understand how applicants take a stand to face the inherently transitional aspect of this APL system.In diesem Beitrag soll die Logik des psychischen Einsatzes der Kandidaten bei dem Vorhaben, ihre erworbenen beruflichen Kompetenzen anerkennen zu lassen (VAE), erfasst werden. Theoretischer Rahmen ist dabei die Psychoanalyse. Herangezogen werden die Arbeiten von Winnicott über die Merkmale des Ãœbergangsobjekts. Der Artikel ist auf eine qualitative Untersuchung gestützt, die über drei Jahre in zwei Universitäten durchgeführt wurde. Dabei wurden 35 VAE-Anträge untersucht. Mit dieser Untersuchung wurde es möglich, ein Modell zu konstruieren, um nachzuvollziehen, wie sich die Kandidaten gegenüber dem Ãœbergangsphänomen positionieren, das dem VAE innewohnt.Esta contribución apunta a captar las lógicas de compromiso psÃquico de los candidatos en un proceso de validación de la experiencia adquirida (VAE). El marco teórico es el del psicoanálisis. Se utilizan los trabajos de Winnicott sobre las caracterÃsticas del objeto transicional. Este artÃculo se basa en una investigación cualitativa realizada durante tres años en dos universidades ; se estudiaron treinta y cinco demandas de VAE. Esta investigación permitió construir un modelo para pensar la manera en que los candidatos se posicionan frente a la transicionalidad inherente al dispositivo de VAE
Correction: PCR and dissection as tools to monitor filarial infection of Aedes polynesiensis mosquitoes in French Polynesia
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