Asymétrie dans la télécollaboration: raisons ingénieriques et conséquences interactionnelles

What are the reasons for asymetry within telecollaboration? In addition to the status of the interlocuteurs that authors mainly refer to, we see them on a socio-institutional level and on the level of the different parters' courses and their aims. They are echoed by the instructions the teachers give their students for their online exchange. As an example, this study analyses a project called Grenover. The analysis shows, moreover, how the students handle different instructions coming from different teachers during their online interaction.Quelles sont les causes de l'asymétrie dans une télécollaboration ? En dehors du statut des interlocuteurs auquel il est habituellement fait référence, nous les situons au niveau socio-institutionnel et celui des (objectifs des) cours des partenaires impliqués. Elles ont une répercussion sur les consignes que donnent les enseignants pour les interactions télécollaboratives. Le projet Grenover nous permet d'illustrer cette répercussion par un exemple ; il nous sert également pour analyser comment les étudiants y gèrent les consignes de source et de nature différentes au sein de leurs interactions

Asymétrie dans la télécollaboration: raisons ingénieriques et conséquences interactionnelles

What are the reasons for asymetry within telecollaboration? In addition to the status of the interlocuteurs that authors mainly refer to, we see them on a socio-institutional level and on the level of the different parters' courses and their aims. They are echoed by the instructions the teachers give their students for their online exchange. As an example, this study analyses a project called Grenover. The analysis shows, moreover, how the students handle different instructions coming from different teachers during their online interaction.Quelles sont les causes de l'asymétrie dans une télécollaboration ? En dehors du statut des interlocuteurs auquel il est habituellement fait référence, nous les situons au niveau socio-institutionnel et celui des (objectifs des) cours des partenaires impliqués. Elles ont une répercussion sur les consignes que donnent les enseignants pour les interactions télécollaboratives. Le projet Grenover nous permet d'illustrer cette répercussion par un exemple ; il nous sert également pour analyser comment les étudiants y gèrent les consignes de source et de nature différentes au sein de leurs interactions

La documentación en las instituciones de la Comunidad Europea. Una aproximación bajo la perspectiva del Tratado de Maastricht

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Functional properties of resting state networks in healthy full-term newborns.

Objective, early, and non-invasive assessment of brain function in high-risk newborns is critical to initiate timely interventions and to minimize long-term neurodevelopmental disabilities. A prerequisite to identifying deviations from normal, however, is the availability of baseline measures of brain function derived from healthy, full-term newborns. Recent advances in functional MRI combined with graph theoretic techniques may provide important, currently unavailable, quantitative markers of normal neurodevelopment. In the current study, we describe important properties of resting state networks in 60 healthy, full-term, unsedated newborns. The neonate brain exhibited an efficient and economical small world topology: densely connected nearby regions, sparse, but well integrated, distant connections, a small world index greater than 1, and global/local efficiency greater than network cost. These networks showed a heavy-tailed degree distribution, suggesting the presence of regions that are more richly connected to others (\u27hubs\u27). These hubs, identified using degree and betweenness centrality measures, show a more mature hub organization than previously reported. Targeted attacks on hubs show that neonate networks are more resilient than simulated scale-free networks. Networks fragmented faster and global efficiency decreased faster when betweenness, as opposed to degree, hubs were attacked suggesting a more influential role of betweenness hub in the neonate network

Regional microstructural organization of the cerebral cortex is affected by preterm birth.

Objectives: To compare regional cerebral cortical microstructural organization between preterm infants at term-equivalent age (TEA) and healthy full-term newborns, and to examine the impact of clinical risk factors on cerebral cortical micro-organization in the preterm cohort. Study design: We prospectively enrolled very preterm infants (gestational age (GA) at birth\u3c32 \u3eweeks; birthweight\u3c1500 \u3eg) and healthy full-term controls. Using non-invasive 3T diffusion tensor imaging (DTI) metrics, we quantified regional micro-organization in ten cerebral cortical areas: medial/dorsolateral prefrontal cortex, anterior/posterior cingulate cortex, insula, posterior parietal cortex, motor/somatosensory/auditory/visual cortex. ANCOVA analyses were performed controlling for sex and postmenstrual age at MRI. Results: We studied 91 preterm infants at TEA and 69 full-term controls. Preterm infants demonstrated significantly higher diffusivity in the prefrontal, parietal, motor, somatosensory, and visual cortices suggesting delayed maturation of these cortical areas. Additionally, postnatal hydrocortisone treatment was related to accelerated microstructural organization in the prefrontal and somatosensory cortices. Conclusions: Preterm birth alters regional microstructural organization of the cerebral cortex in both neurocognitive brain regions and areas with primary sensory/motor functions. We also report for the first time a potential protective effect of postnatal hydrocortisone administration on cerebral cortical development in preterm infants

Altered Cerebellar Biochemical Profiles in Infants Born Prematurely

This study aims to compare the cerebellar biochemical profiles in preterm (PT) infants evaluated at term equivalent age (TEA) and healthy full-term newborns using proton magnetic resonance spectroscopy (1H-MRS). We explore the associations between altered cerebellar metabolite profiles and brain injury topography, severity of injury, and prematurity-related clinical complications. We prospectively collected high quality 1H-MRS in 59 premature infants born ≤32 weeks and 61 healthy full term controls. 1H-MRS data were processed using LCModel software to calculate absolute metabolite concentration for N-acetyl-aspartate (NAA), choline (Cho) and creatine (Cr). PT infants had significantly lower cerebellar NAA (p \u3c 0.025) and higher Cho (p \u3c 0.001) at TEA when compared to healthy controls. Creatine was not different between the two groups. The presence of cerebellar injury was consistently associated with reduced concentrations for NAA, Cho, and Cr. Postnatal infection was negatively associated with NAA and Cr (p \u3c 005), while cerebral cortical brain injury severity was inversely associated with both Cho and Cr (p \u3c 0.01). We report for the first time that premature birth is associated with altered cerebellar metabolite profiles when compared to term born controls. Infection, cerebellar injury and supratentorial injury are important risk factors for impaired preterm cerebellar biochemistry

Electrophilic trifluoromethylation of carbonyl compounds and their nitrogen derivatives under copper catalysis

Recent advances in electrophilic trifluoromethylation reactions of carbonyl compounds and their usual surrogates are highlighted with particular focus on copper-catalysed (or mediated) C–CF3 bond forming reactions. Ketones and aldehydes (notably via their enol ether and enamine derivatives) enable electrophilic trifluoromethylation at the α-carbon of the carbonyl compounds, whereas aldehyde N,N-disubstituted hydrazones undergo electrophilic attack of the cationic or radical CF3 species at the azomethine carbon, thus providing an umpolung alternative to nucleophilic trifluoromethylation of carbonyl compounds. A reversal in reactivity is also observed for conjugated systems. While α,β-unsaturated ketones regioselectively incorporate the CF3 moiety at the α-position of the enones, trifluoromethylation occurs preferentially at the olefinic β-carbon of the corresponding hydrazones

ICNIRP statement on diagnostic devices using non-ionizing radiation: existing regulations and potential health risks

Use of non-ionizing radiation (NIR) for diagnostic purposes allows non-invasive assessment of the structure and function of the human body, and is widely employed in medical care. ICNIRP has published previous statements about the protection of patients during medical magnetic resonance imaging (MRI), but diagnostic methods using other forms of NIR have not been considered. This statement reviews the range of diagnostic NIR devices currently used in clinical settings; documents the relevant regulations and policies covering patients and health care workers; reviews the evidence around potential health risks to patients and health care workers exposed to diagnostic NIR; and identifies situations of high NIR exposure from diagnostic devices in which patients or health care workers might not be adequately protected by current regulations. Diagnostic technologies were classified by the types of NIR that they employ. The aim was to describe the techniques in terms of general device categories which may encompass more specific devices or techniques with similar scientific principles. Relevant legally-binding regulations for protection of patients and workers, and organizations responsible for those regulations were summarised. Review of the epidemiological evidence concerning health risks associated with exposure to diagnostic NIR highlighted a lack of data on potential risks to the foetus exposed to MRI during the first trimester, and on long-term health risks in workers exposed to MRI. Most of the relevant epidemiological evidence that is currently available relates to MRI or ultrasound. Exposure limits are needed for exposures from diagnostic technologies using optical radiation within the body. There is a lack of data regarding risk of congenital malformations following exposure to ultrasound in utero in the first trimester and also about the possible health effects of interactions between ultrasound and contrast media