Mental maps of students - Volume 5

This eurobroadmap working paper, split in 5 different volumes, presents the synthesis of a large survey launched in 2009 on 9000 undergraduate students from 18 different countries. The volume 1 includes the executive summary, plus elements regarding the five different volumes (references, list of figures, etc). The second one presents the aims and the organisation of the survey. The third one deals with the scale of the feeling of belonging. The fourth one presents explanatory models about countries and cities attractiveness. The final volume presents Europe representations in both cartographic and lexical ways

Développement et spécification des aires corticales chez le primate non humain

The primate cerebral cortex has undergone evolutionary expansion and complexification, which is reflected by an increase in the number of cortical areas and an enlargement of the supragranular neuron layers. The developmental mechanisms involved in cortical expansion and aerial specification in primates are considered to be key factors underlying functional dynamics of the primate cortex as well as the highly developed computational abilities of the human brain. This PhD thesis seeks to refine our understanding of non human primate (NHP) cortical specification through two parallel approaches. The first part focuses on the analysis of the development of a cortical area rarely studied, the frontal cortex. Using long term live imaging with two-photon time lapse video microscopy on organotypic slices of embryonic NHP cortex as well as immunostainings experiments, we have characterized the morphology and proliferative behavior of frontal cortex progenitors. While our results point to conserved characteristics of cortical development between caudal and rostral regions of the cortex, it also reveals a differential temporal regulation of the balance between proliferative and differentiative divisions between the visual and the frontal cortex. In the second part of this work, we aimed to assess the role of thalamocortical afferents (TCA) on areal identity, focusing on their influence on cortical progenitor proliferation in the visual cortex of the embryonic NHP. A first aim was to determine the relationship between the thalamocortical pathway and the germinal zones in the visual cortex, before assessing the influence of TCA on cell cycle kinetics. Tracing experiments show that the spatiotemporal features of embryonic TCA development provide the necessary circumstances for TCA to interact with and have an influence on progenitors during corticogenesis. We provide evidence of a temporally regulated and area-specific mitogenic effect by TCA on progenitors in the embryonic visual NHP cortex. Together, the results of this PhD thesis provide new insights on area specific features of NHP corticogenesis and on the mechanisms involved in areal specificationLe cortex cérébral primate a subi une expansion et une complexification au cours de l’évolution, ce qui s’est traduit par une augmentation du nombre de zones corticales et un élargissement des couches de neurones supra granulaires. Les mécanismes développementaux impliqués dans l'expansion corticale et la spécification des aires corticales chez le primate sont considérés comme des facteurs clés sous-jacents à la dynamique fonctionnelle du cortex des primates et des capacités de computation hautement développées du cerveau humain. Cette thèse de doctorat cherche à affiner notre compréhension de la spécification corticale des primates non humains (PNH) à travers deux approches parallèles. La première partie se concentre sur l'analyse du développement d'une aire corticale rarement étudiée, le cortex frontal. En utilisant des techniques d'immunofluorescence et de microscopie en temps réel, nous avons caractérisé la morphologie et le comportement prolifératif des progéniteurs du cortex frontal. Alors que nos résultats indiquent des propriétés conservées du développement cortical entre les régions caudale et rostrale du cortex, ils révèlent également une régulation temporelle différentielle de l'équilibre entre la prolifération et la différenciation des progéniteurs corticaux entre le cortex visuel et le cortex frontal. Dans la deuxième partie de ce travail, nous avons cherché à évaluer le rôle des axones thalamocorticaux (TCA) sur l'identité des aires corticales, en nous concentrant sur leur influence sur la prolifération des progéniteurs corticaux dans le cortex visuel du PNH embryonnaire. Un premier objectif était de déterminer la relation entre la voie des TCA et les zones germinales du cortex visuel, avant d'évaluer leur influence sur la cinétique du cycle cellulaire. Des expériences de traçage montrent que les TCA sont en mesure d'interagir avec les progéniteurs corticaux pendant la corticogenèse. Nous montrons également que les TCA modulent le cycle cellulaire des progéniteurs du cortex visuel embryonnaire du PNH. Ensemble, les résultats de cette thèse fournissent de nouvelles perspectives sur les propriétés de la corticogenèse chez le PNH et sur les mécanismes impliqués dans la spécification des aires corticale

Peripheral inflammation increases PKR activation, Tau phosphorylation and amyloid β production in wild-type mice

International audienceSystemic inflammation is correlated with dementia progression. Pro-inflammatory molecules can communicate from the periphery to the central nervous system to induce neuroinflammation and neurodegeneration. Our protein of interest is the pro-apoptotic kinase PKR (the double strand-RNA dependent protein kinase). Increased activated PKR levels were found in AD patients brain and cerebrospinal fluid. PKR activation can be triggered by inflammatory stresses and induces neurotoxicity in vitro. Is in vivo PKR-mediated inflammation involved in AD neurodegenerative process

Effect of poloxamer 188 vs placebo on painful vaso-occlusive episodes in children and adults with sickle cell disease : a randomized clinical trial

Key PointsQuestionCan poloxamer 188, an agent that is reported to reduce blood viscosity and cell-cell interactions, effectively reduce the duration of vaso-occlusive episodes (painful crises) in hospitalized patients with sickle cell disease? FindingsIn this randomized clinical trial that included 388 children and adults with sickle cell disease, treatment with poloxamer 188 vs placebo resulted in mean time to last dose of parenteral opioids during vaso-occlusive episodes of 81.8 vs 77.8 hours, a difference that was not statistically significant. MeaningAmong patients with sickle cell disease, poloxamer 188 did not significantly shorten the duration of painful vaso-occlusive episodes

Effect of Poloxamer 188 vs Placebo on Painful Vaso-Occlusive Episodes in Children and Adults With Sickle Cell Disease: A Randomized Clinical Trial.

Key PointsQuestionCan poloxamer 188, an agent that is reported to reduce blood viscosity and cell-cell interactions, effectively reduce the duration of vaso-occlusive episodes (painful crises) in hospitalized patients with sickle cell disease? FindingsIn this randomized clinical trial that included 388 children and adults with sickle cell disease, treatment with poloxamer 188 vs placebo resulted in mean time to last dose of parenteral opioids during vaso-occlusive episodes of 81.8 vs 77.8 hours, a difference that was not statistically significant. MeaningAmong patients with sickle cell disease, poloxamer 188 did not significantly shorten the duration of painful vaso-occlusive episodes

Recent progress in L-H transition studies at JET: Tritium, Helium, Hydrogen and Deuterium

We present an overview of results from a series of L-II transition experiments undertaken at JET since the installation of the ITER-like-wall (JET-ILW), with beryllium wall tiles and a tungsten divertor. Tritium, helium and deuterium plasmas have been investigated. Initial results in tritium show ohmic L-H transitions at low density and the power threshold for the L-H transition (P-LH) is lower in tritium plasmas than in deuterium ones at low densities, while we still lack contrasted data to provide a scaling at high densities. In helium plasmas there is a notable shift of the density at which the power threshold is minimum ((n) over bar (e,min)) to higher values relative to deuterium and hydrogen references. Above (n) over bar (e,min) (He) the L-H power threshold at high densities is similar for D and He plasmas. Transport modelling in slab geometry shows that in helium neoclassical transport competes with interchange-driven transport, unlike in hydrogen isotopes. Measurements of the radial electric field in deuterium plasmas show that E-r shear is not a good indicator of proximity to the L-H transition. Transport analysis of ion heat flux in deuterium plasmas show a non-linearity as density is decreased below (n) over bar (e,min). Lastly, a regression of the JET-ILW deuterium data is compared to the 2008 ITPA scaling law