146 research outputs found

    Heat-induced and spontaneous expression of Hsp70.1Luciferase transgene copies localized on Xp22 in female bovine cells

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    <p>Abstract</p> <p>Background</p> <p>Expression of several copies of the heat-inducible <it>Hsp70.1Luciferase </it>(<it>LUC</it>) transgene inserted at a single X chromosome locus of a bull (<it>Bos taurus</it>) was assessed in females after X-chromosome inactivation (XCI). Furthermore, impact of the chromosomal environment on the spontaneous expression of these transgene copies before XCI was studied during early development in embryos obtained after in vitro fertilization (IVF), when the locus was carried by the X chromosome inherited from the bull, and after somatic cell nuclear transfer (SCNT) cloning, when the locus could be carried by the inactive Xi or the active Xa chromosome in a female donor cell, or by the (active) X in a male donor cell.</p> <p>Findings</p> <p>Transgene copies were mapped to bovine Xp22. In XX<sup><it>LUC </it></sup>female fibroblasts, i.e. after random XCI, the proportions of late-replicating inactive and early-replicating active X<sup><it>LUC </it></sup>chromosomes were not biased and the proportion of cells displaying an increase in the level of immunostained luciferase protein after heat-shock induction was similar to that in male fibroblasts. Spontaneous transgene expression occurred at the 8-16-cell stage both in transgenic (female) embryos obtained after IVF and in male and female embryos obtained after SCNT.</p> <p>Conclusions</p> <p>The X<sup><it>LUC </it></sup>chromosome is normally inactivated but at least part of the inactivated X-linked <it>Hsp70.1Luciferase </it>transgene copies remains heat-inducible after random XCI in somatic cells. Before XCI, the profile of the transgenes' spontaneous expression is independent of the epigenetic origin of the X<sup><it>LUC </it></sup>chromosome since it is similar in IVF female, SCNT male and SCNT female embryos.</p

    Dynamique Hydro-Erosive Actuelle Des Bassins Versants Endoreiques De La Region De Niamey (Sud-Ouest Du Niger)

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    La généralisation du ravinement et la baisse de la productivité des terres sont quelques-unes des principales contraintes qui assaillent l’utilisation des sols au Sahel. Pour gérer efficacement ces sols, une évaluation des processus hydro-érosifs est nécessaire. Ce travail a ainsi pour objectif d’analyser la dynamique hydro-érosive sur un site expérimental installé depuis 2004 dans la région de Niamey (Niger). Sur ce site, le dispositif de mesure est composé de huit parcelles de mesures de ruissellement et d’érosion, des stations hydrométriques à l’exutoire des deux bassins versants endoréiques et de plusieurs piquets destinés aux suivis morpho-dynamiques des ravines. Après une décennie d’observation, les ruissellements mesurés sur les parcelles se caractérisent par une dynamique saisonnière croissante sur les surfaces encroûtées (croûtes biologique et d’érosion) et décroissante sur les surfaces cultivées. Le coefficient de ruissellement varie de 5 % sur la surface cultivée à 58 % sur la croûte d’érosion. Au cours des 10 années de mesure, ce coefficient a connu une forte croissance en particulier sur la jachère (+ 80 %) et sur la surface cultivée (+ 300 %), traduisant ainsi la dégradation des sols. A l’échelle des bassins versants, l’augmentation du coefficient de ruissellement s’accompagne d’une érosion aréolaire qui décape le sol à une vitesse moyenne de 5 mm/an et d’une érosion linéaire active, de l’ordre de 4 m3/an au niveau des ravines suivies. Les transferts sédimentaires qui en résultent agissent sur le fonctionnement morpho-sédimentaire des cours d’eau. Des aménagements antiérosifs sont nécessaires pour dissiper les processus hydro-érosifs et préserver les services écosystémiques des sols des bassins. Widespread gullying and the declining land productivity are some of the main constraints plaguing land use in the Sahel. In order to effectively manage these soils, it has become necessary to assess the hydro-erosive processes. The current study, thus, aims at analyzing the hydro-erosion dynamics on an experimental site installed since 2004 in the Niamey region (Niger Republic). On this site, the measurement device is made up of eight runoff and erosion measurement plots, hydrometric stations at the outlet of the two endorheic watersheds and several stakes intended for morpho-dynamic monitoring of the gullies. After a decade of observation, the runoff measured on the plots is characterized by an increasing seasonal dynamic on encrusted surfaces (biological and erosion crusts) and a decreasing one on cultivated surfaces. The runoff coefficient varies from 5% on the cultivated area to 58% on the erosion crust. Over the 10 years of measurement, this coefficient has greatly increased, especially on the fallow (+ 80%) and on cultivated area (+ 300%); this increase consequently reflects soil degradation. At the watershed scale, the increase in the runoff coefficient is accompanied by area erosion (or the erosion of the area out of the basin) which strikes the soil at an average speed of 5 mm/year and active linear erosion measuring 4 m3/year as observed at the monitored (the ongoing investigated) gullies. The resulting sediment transfers act on the morpho-sedimentary functioning of rivers. Anti-erosion facilities are necessary to dissipate the hydro-erosive processes and preserve the ecosystem services of the soil in the basin

    Increasing river flows in the Sahel ?

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    Despite the drought observed since 1968 in most of the West African Sahel, runoff and rivers discharges have been increasing in the same region. This trend is related with land use change rather than climate change. This paper aims to describe the regional extension of such a phenomenon and to demonstrate that the increase in runoff is observed from the point scale up to the regional scale. It highlights the opposition of functioning between a Sahelian zone, where the Sahel’s paradox applies, and the Sudanian and Guinean areas, where runoff has been logically decreasing with the rainfall. The current trend is evidenced using experimental runoff plots and discharge data from the local to the regional scales

    Contentores, corpos e topologias: Uma análise integral da coleção arqueológica de Pampa Grande (Salta, Argentina)

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    A partir del análisis de la colección arqueológica de Pampa Grande (Salta, Argentina) se indagan diversos contenedores (animales, cerámicos, vegetales) en tanto cuerpos, junto a las operaciones topológicas que dan sentido a los mismos en contextos funerarios. Metodología: análisis de la colección arqueológica y documentación asociada junto a antecedentes bibliográficos. Conclusiones: se proponen otros vínculos y efectividades epistémicas para los contenedores lógicos de Pampa Grande a partir de movimientos (romper, voltear, combinar, asentar, envolver) que habilitan nuevos aspectos topo-lógicos tras o hacia la muerte, alterando sus capacidades afectivas y potencialidades.Originalidad: este artículo pretende aportar una nueva mirada sobre diversos elementos que conforman una colección arqueológica y que suelen ordenarse según la especialidad del investigador, antes que seguir las conexiones que el material mismo sugiere. Así, este trabajo aporta una red relacional alternativa que vincula diversos cuerpos contenedores desde un abordaje topológico que permite ir más allá de nuestra usual mirada académica sobre los mismos.From the analysis of the archaeological collection at Pampa Grande (Salta, Argentina) different containers (animals, ceramics, vegetables) are explored as bodies, together with the topological operations that confer meaning to them in funerary contexts. Methodology: Analysis of the archaeological collection and associated documentation together with bibliographical background. Conclusions: Other links and epistemic effectivities are proposed for the logical containers of Pampa Grande based on movements (breaking, turning, combining, settling, wrapping) that enable new topological aspects after or towards death, altering their affective capacities and potentialities. Originality: This article aims to provide a new look at the various elements that make up an archaeological collection and that are usually ordered according to the specialty of the researcher, rather than following the connections that the material itself suggests. Thus, this work provides an alternative relational network that links different container bodies from a topological approach that allows us to go beyond our usual academic view of them.A partir da análise da coleção arqueológica de Pampa Grande (Salta, Argentina), são questionados diversos contentores (animais, cerâmicos, vegetais) de corpos, junto às operações topológicas que lhes dão sentido em contextos funerários. Metodologia: análise da coleção arqueológica e documentação associada junto a antecedentes bibliográficos. Conclusões: propõem-se outros vínculos e efetividades epistêmicas para os contentores lógicos de Pampa Grande a partir de movimentos (quebrar, virar, combinar, assentar, envolver) que permitem novos aspectos topológicos após a morte ou em direção a ela, alterando suas capacidades afetivas e potencialidades. Originalidade: este artigo pretende contribuir com uma nova visão sobre diversos elementos que conformam uma coleção arqueológica e que costumam ser organizados segundo a especialidade do pesquisador, antes que seguir as conexões que o material em si sugere. Assim, este trabalho contribui com uma rede relacional alternativa que vincula diversos corpos contentores a partir de uma abordagem topológica que possibilita ir mais além da nosso usual olhar acadêmico sobre eles.Fil: Lema, Veronica Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Antropología de Córdoba. Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Instituto de Antropología de Córdoba; Argentin

    The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2

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    Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase&nbsp;1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation&nbsp;disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age&nbsp; 6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score&nbsp; 652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc&nbsp;= 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N&nbsp;= 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in&nbsp;Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in&nbsp;Asia&nbsp;and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701

    Apprentissage de l'anglais en section européenne au lycée : représentations et pratiques

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    This research is based on a longitudinal study of two categories of secondary high school pupils, a group involved in "European" programmes in different types of schools, comprehensive, technical and vocational, in which a school subject is taught through English, and a control group of pupils who follow a traditional curriculum in a French secondary school. After introducing the characteristics of the programmes, the local conditions and specificities of the schools in which the observations have taken place, and the pupils who have acted as informants in the research, this study moves on to an analysis of the pupils' written work in English and of the influence of the mental conceptions they hold of their learning rocesses and of the teaching they receive. The outcomes of the study are first that the communicative competence of European programme pupils does not seem to be notably more versatile or precise than the one developed by "ordinary" pupils, and then that direct experience of communicating in a foreign language has a significant cognitive impact on the language proficiency of adolescents in a school context.La recherche présentée s'appuie sur un suivi longitudinal à la fois d'élèves scolarisés en sections européennes dans des séries générales, technologiques et professionnelles, et d'un groupe-témoin de lycéens qui ne suivent pas ce type d'enseignement. Après une présentation du dispositif spécifique que constituent les sections européennes, de la réalité locale des établissements observés et des lycéens ayant participé à l'enquête, ce travail se poursuit par l'analyse des productions écrites en anglais de ces lycéens et l'étude des représentations qu'ils ont de leur apprentissage et de l'enseignement qu'ils reçoivent. Cela permet en premier lieu de percevoir que les élèves inscrits en section européenne ne parviennent pas à une compétence discursive en anglais plus vaste et plus ciblée que celle des autres lycéens de leur âge scolarisés dans des classes " ordinaires ", d'autre part de mettre en évidence l'impact cognitif de l'expérience personnelle de la langue étrangère sur le progrès des élèves

    Le Collège québécois : introduction bibliographique /

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    1976

    Le Collège québécois : introduction bibliographique /

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    Le Collège québécois : introduction bibliographique /

    No full text
    1976
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